Title of Invention	SYSTEM FOR THE GENERATION, MODIFICATION AND/OR VISUALISATION OF PROGRAMS FOR CONTROLLING GRINDING MACHINES.
Abstract	A virtual teach-in module for programming grinding machines or other kinds of machine tools includes a graphic user surface. This surface includes the visual display of blanks, workpieces and tools. The elements shown can be displaced arbitrarily relative to one another by means of suitable operator elements. The resultant displacements are recorded by the virtual teach-in module and converted into a machine control program, or an existing machine control program is varied based on the displacements.

Title of Invention

SYSTEM FOR THE GENERATION, MODIFICATION AND/OR VISUALISATION OF PROGRAMS FOR CONTROLLING GRINDING MACHINES.

Abstract

A virtual teach-in module for programming grinding machines or other kinds of machine tools includes a graphic user surface. This surface includes the visual display of blanks, workpieces and tools. The elements shown can be displaced arbitrarily relative to one another by means of suitable operator elements. The resultant displacements are recorded by the virtual teach-in module and converted into a machine control program, or an existing machine control program is varied based on the displacements.

Full Text	VIRTUAL TEACH-IN SYSTEM FIELD OF THE INVENTION The invention relates in general to a system for generating, varying and/or displaying programs for machine control. In particular, the invention relates to a system for generating, varying and/or displaying programs for controlling grinding machines. BACKGROUND OF THE INVENTION Machine tools are as a rule program-controlled in that machining operations which are to be performed on a workpiece proceed under program control. To generate a relative motion between the tool and the workpiece, a plurality of NC axes are provided. For example, a grinding head is supported on a suitable linear guide, which in turn is provided with an NC (numerically controlled) drive mechanism. Actuating one or more such axes creates a positioning motion. In grinding spiral grooves on drilling tools, for instance, a plurality of motion components must be superimposed in order to achieve a suitable relative motion between the workpiece and the tool. Numerically controlled machine tools, and control programs for them, are known. European Patent Disclosure EP 0 530 364 A1, for example, discloses an interactive numerical control that produces a display of a workpiece on a monitor on the basis of existing NC data. An interactive variation of the NC data can be displayed directly. Effects of data changes are thus made immediately visible. The system includes storage means, calculation means, display means and input means. From the - display of the machining process on a monitor, the NC data can be corrected directly on the screen. Programming NC machines demands certain skills, both in the programming language used and in terms of the special -1A- conditions involved in machining certain surfaces of the workpiece. SUMMARY OF THE INVENTION It is an object of the invention to make it easier to operate NC machines. This and other objects of the invention are attained by a system that has a teach-in module, which can be formed by a program running on suitable hardware, for instance. The teach-in module allows a visual, preferably three-dimensional display of a workpiece and a working tool. This is possible even if a machine control program of any kind is not yet available. Presume, for example, that it is desired to form a machined tool from a workpiece. A blank, or an incompletely machined tool, is then displayed as the workpiece. The blank or the partially machined tool can be electronically stored in a memory and then retrieved from the memory, for example. Alternatively, the teach-in module may be provided with the capability of putting together blanks or starting bodies for producing machined tools from simple geometric shapes, such as cylinders, parallelepipeds, cubes, or the like. The teach-in module can be provided with suitable scaling functions, so that the working tools, blanks or basic bodies can be displayed visually in a desired size and with a required dimensional ratio. The teach-in module is arranged to display an operator-specified motion of the workpiece and the working tool relative to one another in response to suitable manual inputs. The motions can be input as single motion steps, for, instance, or as motions that follow a predetermined path. Specifying a path can be done for instance using typical paths, such as straight lines, helical lines, or similar courses, that are stored in a memory. Once again, a scaling function may be provided. It is also considered expedient to enable either incremental positioning or -2- input of a motion path. Smoothing functions can be introduced via a manually input path. One component of the teach-in module is that a machine control program is generated or modified on the basis of the relative motion which is input into the teach-in module, between a display of the working tool and a display of the workpiece. While the teach-in module is displaying the machining progress resulting from the relative motion between the workpiece and the working tool, or in other words is displaying the recesses generated virtually on the blank, for instance by means of a grinding wheel, the machine control data that correspond to such a machining operation are generated at the same time. In this way, the machine control program can be generated by virtual teaching-in. If the machine control program already exists, then it can be modified by the virtual teach-in method. This simplifies the operation of a corresponding numerically controlled machine tool considerably. It makes it possible in a simple manner to manipulate machine control programs, which describe not only the motion sequence but also the speeds of the axes of a grinding machine as well as status changes at the inputs of a control unit, such as an SPS control unit (for instance, turning the coolant valves or the grinding wheel spindle on and off). As a rule, such machine control programs comprise not only arranging individual commands regarding single motions of the machine axes but also SPS control commands. Program lines and program blocks made up of a plurality of program lines control the motion of one or more axes between two points in space. The virtual teach-in module now makes it possible for instance to vary existing program lines, or existing blocks composed of a plurality of program lines, to add new program lines or blocks, and to delete existing program lines or blocks. -3- To that end, the virtual teach-in module preferably has a storage means, which is arranged for storing in a memory tool data and operating instructions about the relative motions between the working tool and workpiece. To that end, a memory present in hardware form, for instance, is put under the control of a suitable program or program section, which is executed on a suitable computer. The computer also includes a calculation means, to which a corresponding program section and the hardware that runs that program or program section belong. The calculation means processes the work instructions that are present in and furnished by the storage means, so as to change or add to the workpiece data and/or tool data in accordance with the work instructions, as appropriate for machining of the workpiece by the tool in accordance with the relative motion defined by the work instructions. In this way, a material erosion, for instance, and/or optionally tool wear as well, can be modeled. This is displayed by the display means, which includes a display device and the corresponding program, which serves to make data graphically visible on the display device. An input means serves to detect desired relative motions between working tool and workpiece, which are converted into corresponding work instructions, which in turn are stored or buffer-stored in memory by the storage means. The input means can include input devices and a playback device, on which "virtual input keys or the like can be shown. In an advantageous embodiment, a transformation means is also present which converts the work instructions generated as above into a machine control program. Alternatively, the work instructions can correspond directly to a machine control program, in which case transformation can be dispensed with. In the manipulation of the display provided by the virtual teach-in module, the machine control program is generated and/or varied. This can include both the above-described qualitative -4- actions and changes in the machine control program and also changes in the data that are assigned to individual parts of the program. The input means, which is formed for instance, by a special input device, or an input device in conjunction with input panels shown on a screen, can include both operator panels associated with individual machine axes and operator panels for configurable axes that do not match the machine axes. This makes operation even simpler. the teach-in module can be contained in or connected to a simulation module, which allows the machining that has been input to be shown in the manner of a motion-picture film. In an advantageous embodiment, the simulation can also be performed either incrementally or in slow motion or in time-lapse form, as needed. The simulation can be interrupted and can be corrected by the teach-in module, if that should be necessary. It can also be advantageous to provide a means with which the resultant workpiece dimensions can be determined from the visual display. Such means can for instance be a cursor, with which points of the workpiece can be selected or addressed arbitrarily, in which case this means determines dimensional relationships between the points. The view shown by the display means is preferably a three-dimensional display, which provides the viewer with a three-dimensional impression of the virtually created workpiece. The system of the invention can either be operated on a separate computer or be integrated with the controller of an NC machine, for instance. In the first instance, NC programs for NC machines can be set up interactively, after which the program thus set up is transferred to the otherwise conventional NC machine. Data storage media or data lines can be used for this purpose. -5- BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS Fig. 1 shows a general block diagram of a system for generating, varying and/or displaying machine control programs; Fig. 2 shows a general block diagram of the teach-in module of Fig. 1; Fig. 3 shows the data flow of the teach-in module depicted in the form of a block circuit diagram; Fig. 4 shows an element of the working tool set in a schematic illustration; Fig. 5 shows a grinding machine and both a real and a configurable axis in a schematic plan view; Fig. 6 shows an operator panel for inputting desired relative motions between the virtual working tool and the virtual workpiece; Figs. 7-9 are each a screen display of the virtual working tool and the virtual workpiece when the motion is being input; Fig. 10 is a screen display of the working tool and workpiece when desired machining operations are being input; Fig. 11 is a screen display of the machine for performing the machining operations of Figs. 7-10; Fig. 12 shows an operator panel for the simulation module; Fig. 13 is a screen display during the course of simulation; Fig. 14 shows an expanded view of a portion of the screen display of Fig. 13; and Fig. 15 shows the screen display of an SPS monitor. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Fig. 1 shows a teach-in system 1, which serves to generate, vary and display programs for machine control. The system 1 has a teach-in module 2, which is used to set up machine control programs interactively. The teach-in module 2 includes a computer program and the underlying hardware. It has a program part 4, which is arranged to act on data, schematically -6- characterized by a block 5 in Fig. 1, and on a machine control program. The teach-in module has a collision module 2a, seen in Fig. 3, and a time calculation module 2b. The collision module 2a serves to detect undesired collisions between tool and workpiece, that is, collisions that do not constitute contact in the sense of (metal-cutting) workpiece machining. The time calculation module 2b serves to determine the machining time that will result when the machine control program is actually executed. The data can be delivered to the teach-in module 2 from a block 6, which can for example contain data that form a picture of an unmachined workpiece. Once the initial data have been transferred from block 6 to block 5, they are applied by the teach-in module 2 for display and manipulation of the display. On the basis of the manipulation of the display, action is exerted in turn on the data in block 5 and the machine program in program part 4 again, until the desired data set and machine program have been generated. This is then output as a machine control program, as repre ented in Fig. 1 by a block 7. As shown in Fig. 2, the teach-in module 2 includes not only a computer with a control and processing unit, which forms an arithmetic unit 11, but also a memory 12, a monitor 14, and an input device 15. The memory 12, with a section of a program 16 running on the arithmetic unit 11, forms a memory unit 17 for storing workpiece data, tool data, and instructions that characterize a relative motion between the tool and workpiece. A further section of the program 16, together with the monitor 14, forms a display means 18 for displaying the workpiece, the tool, and the motion of workpiece and tool relative to one another. Operating the teach-in system is done via a further section of the program 16 in combination with the input device 15 and the monitor 14. The applicable program section, together with the -7- input device 15 and the monitor 14, forms an input means 19. The teach-in system 1 described thus far functions as follows. As an example, it will be assumed for now that there is not yet any machine control program. Data transferred from block 6 to the teach-in module 2 therefore describe a workpiece in the unmachined state, plus at least one selected working tool. This working tool is shown on the monitor 14, together with the workpiece from block 4, by the display means 18. With the input device, motions in the display of the workpiece and/or of the tool are now specified. SPS control commands can be input or specified as well. These include turning coolant valves on and off, for instance. Moving the displays and inputting of the SPS control commands can be done from a keyboard, but is preferably done by inputs using a joystick or mouse, in conjunction with an input menu or other displays shown on the monitor 14 . The motions that result are recorded as data and converted into control instructions for an NC machine. In this way, a machine control program is created in block 5, step by step. Once the workpiece and tool have run through all the desired positions, the teach-in operation is ended, and in block 7 the finished machine control program, defined in a sense by the track of the relative motion of the workpiece display and tool display, is output. The machine control program can now be transferred directly to a machine tool, which then executes it. Depending on the machine kinematics (axis arrangement) of the machine tool on which the program is to be executed, and depending on the machine geometry, suitable data can be defined in a configuration menu. Other configuration data, such as the description of the geometry and disposition of the tools (grinding wheels) and the geometry of the workpiece, as well as the chucking means, can: be specified from outside, via interfaces. For example, these can be written-in using data -8- storage media. The data to be written-in, which make up an input data set, can include the following: a) Tool data: description of the. geometry of the working tools, and especially of grinding machines used as working tools, and their position on being installed in the machine. In particular, individual, wheels can be combined into, sets of wheels, of the kind shown in Fig. 4. These data can be stored in datasets, or files, that are either on hand or can be furnished as needed. The data can also be stored in a data base that is part of the teach-in system or is used as needed. b) -Data on the chucking means: description of the geometry of the chucking means of the workpiece. These data can again be stored in datasets or files, or in a data base. c) Workpiece data: description of the geometry of the workpiece as an unfinished part. These data will have already been stored in datasets or files, or in a data base. Alternatively or in addition, unfinished part geometries can be derived from simple geometric shapes. d) Machine control program data (if available): description of the NC program used. This program is either in the form of a dataset or file, or can be transferred to the teach-in system via data storage media or over a line. e) Machine data: description of the geometry and axis configuration of the machine used. The data that are output include: a) Modified machine control program data: The modified or re-created machine control program is output in the form of a dataset or file. If the teach-in system is part of a machine tool, it is transferred directly to the machine controller. If the teach-in system is part of a computer located at a distance from a machine tool, then it can be transferred to the machine controller over a line or via a data storage medium. -9- b) Screen: The execution and modification of the machine control program are shown graphically by material erosion on the screen. If an undesired collision occurs inside the machine, a warning can be issued and the program can be discontinued on the spot. If needed, the program line in which the collision occurred can be written into a log file. c) Generated workpiece model: The workpiece model that has been generated can be transferred to a CAD system or some other system, for further processing. To further illustrate the operation of the virtual teach-in system, Fig. 3 schematically shows the data flow of the system. Only one program section is shown. The communication of the virtual teach-in system with other system components, and starting the system operation, are done by a higher-order program that is not described herein nor shown in the drawings since details thereof are well known and not deemed necessary here. This also includes transferring the generated machine control program to the machine. From an existing machine control program, which may even still be fragmentary, in a hard disk memory or from a machine control program arriving as a continuous data stream, displacement paths of machine axes are generated in a processing module 16. In Fig. 3, this is shown for five different axes X, Y, Z, A and C. The processing module also receives data about the machine geometry and kinematics, the wheel geometry, the chucking means, and the workpiece geometry. It is also connected to the input 19 means with which the user can perform an operation, interrupt or continue the processing, and add, delete or modify program lines or blocks in a targeted way as needed. From these data, the processing module sets up a workpiece model, carries out a collision observation, and calculates the machining time required. This calculation, along with the collision observation and the workpiece model, are displayed by the display -10- means 18. The displacement paths generated by processing module 16 are transferred to the memory unit 17 and thus recorded on the hard disk. They can be transferred to the machine in the form of a machine control program or can first be transformed into a machine control program and then transferred to the machine. The machine is schematically shown in plan view in Fig. 5. It has a machine bed 21, on which a workpiece carrier 22 is supported so as to be pivotable about a vertical axis C. The workpiece carrier 22 is also adjustable in a horizontal direction by means of a further NC axis X. It also carries a receiving device 24-for a workpiece 25, such as a drilling tool. A rotary positioning device, which represents a further NC axis A, can be provided on the receiving device 24 as needed. In the vicinity of the workpiece carrier 22, a grinding head 26, which carries one or more grinding wheels 27, 28, 29, is also provided. As needed, the grinding head 26 is adjustable in a direction that coincides with the pivot axis of the grinding spindle by means of an NC axis Z and linearly in a direction parallel to the C axis (NC axis Y). The workpiece 25 is not linearly adjustable relative to the workpiece carrier 22. An axial motion (from the standpoint of the grinding wheels 27, 28, 29) of the workpiece 25 in the direction X can be accomplished by superimposing motions in the Z direction (motion of the grinding head) and in the X direction (motion of the workpiece carrier). For the interactive teach-in programming of this NC machine, the virtual teach-in module whose operator panel is shown in Fig. 6 is used. The illustration shows an operator panel 31 for display by the display means 18 on a monitor 14. The operator panel 31 includes a plurality of operator keys 32 and display areas 33. The operator keys include keys X, Y, Z, A, C for selecting NC axes of the grinding machine. The keys marked "-", "+" and "E", for high-speed mode, serve to control the motion. -11- The present feed increment can be adjusted in linear or angular increments. A repeat key ReDo restores the last step, to have been deleted. Another operator key panel UnDo deletes the last step to have been input. For further selection of the axes, an operator key panel K is also provided, which identifies a configurable axis. This axis may deviate from the NC axes that are actually present and can be assembled by superposition of the motion of the various actually present machine axes X, Y, Z, A, and C. All the motions are conceived of and executed as linear between two points in space. Changes in angular coordinates are represented by linear angle changes. The motions of the machine axes can be executed as either a motion of one axis or the simultaneous motion of a plurality of axes. In the single motion, one axis is selected and moves in accordance with the feed rate selected and with the number of repetitions of the incremental motions along the associated distance. The simultaneous motion of a plurality of axes can be described as the succession of single axis motions. The "multiaxis motion" mode is turned on, and the axes are moved in succession to the desired terminal point. The "multiaxis motion" mode is then turned off again and all the (linear) motions since the "multiaxis motion" was turned on are combined into a simultaneous motion of all the axes involved. Instead of combining single motions of machine axes into a superimposed axis motion, in some case the "configurable axis" can also be used. It is put together from the machine axes. The configurable axis does not exist as a real axis, however. The motion along this axis must be generated by the simultaneous motion of one or more machine axes. In most cases, it is expedient, to place a configurable axis in the center axis of the workpiece. Moving the working tool {grinding wheel) parallel to the workpiece axis is thus possible. A motion of the grinding -12- wheel along this axis is thus always parallel to the longitudinal axis of the workpiece and need no longer be programmed as a combined motion of two machine axes, as can be seen from Fig. 5. The configurable axis is operated like a machine axis. In the machine control program (NC program), however, this motion is composed of the machine axes that are present. The definition of the configurable axes is provided by a configuration dataset, or file. This configuration dataset or file can be modified via a menu. Thus the configurable axes can easily be adapted to different machine configurations or to the needs of special working tools or workpieces as well. In the process, the orientation of the particular configurable axis in space and the way in which it is coupled to the machine axes are defined. In the movement of the wheel set and workpiece through the machine space, collisions can occur. These collisions can be classified in the following categories: (1) collisions of the grinding wheel with the workpiece in the high-speed mode; (2) collision of the grinding wheel with the workpiece carrier or chucking means and other machine parts; (3) collision of the workpiece with machine parts or with parts of the grinding wheel that do not perform metal-cutting machining: and (4) collision of the workpiece with a grinding wheel that is not the actual wheel that performs metal-cutting machining. Such collisions are of importance particularly whenever existing NC programs are being analyzed. The collision observation can be added during the execution of the NC program, either in single-step processing or in continuous processing. However, it is not an absolute necessity that it be turned on, and thus it represents an optimal property of the system. -13- For the collision observation, two different operating modes are possible: a) On-line mode: The graphics are shown in the collision observation, and the material erosion is updated. If a collision occurs, the program processing stops, and a warning is issued. b) Off-line mode: The collision observation is performed without graphics, and collisions are output to a log file. The recording of desired workpiece motions is shown in Figs. 6-14. The point of departure is for instance an existing machine control program. This program can be displayed by means of a simulation run. The operator panel shown in Fig. 12, which is shown on a monitor, is used for this purpose. The result of the simulation can for instance be a workpiece view shown in Fig. 10. Optionally, the display can be switched over to the elevation view of the entire machine, as shown in Fig. 11. If the outcome of the machining is as desired, then the NC program can remain unchanged. If it is to be changed, however, then the simulation run can be interrupted at a desired point and a change to the virtual teach-in operating mode can be made. This is shown in Figs. ,13 and 14. The operator panel of Fig. 14, which is present in addition to the operator panel of Fig. 13, permits the recording of motion data of the grinding wheel and/or the workpiece. These data can be input by means of an input device, such as a joystick or mouse. Pressing the operator key 64 labeled "Record" translates the motions that have been input into one or more machine control program lines. During the continuous simulation run (Fig. 12), the machine control program is executed continuously, and the following actions can be actuated by the user; a) Starting or continuing the execution of the machine control program: The execution is started, or is continued after a temporary stop, by pressing key 51. -14- b) Temporary stop in execution of the machine, control program: The execution is interrupted but can be continued, by-pressing key 52. c) Terminating execution of the machine control program: The execution is terminated and can be begun again only by means of a restart, by pressing key 53. d) Fast forward in machine control program execution: More than one program set is skipped, by pressing key 54. If desired, one, can skip to the next machining operation. e) Fast rewind in machine control program execution: More than one program set is rewound, by pressing key 55. If desired, one can skip back to the previous machining operation. The graphics are then reset by the applicable operations, and the workpiece is displayed the way it looked when the corresponding machine control program lines were executed. The machining time is reset as well. f) Switchover between views with and without the machine space (e.g., as shown in Fig. 11) by pressing button 56. The single-step processing of the machine control program can be actuated by pressing the temporary-stop key 52. As shown in Fig. 13, the grinding wheel 27 remains in its current position, and the current machine control program lines and the machining time elapsed thus far are displayed. As shown in Fig. 14, the following actions can be actuated: a) Single step forward: The next program line is executed by pressing key 61. The graphics and machining time are updated. b) Single step back: The processing of the program is reset by one line by pressing key 62. The graphics and machining time are updated; that is, any material erosion that may exist is rescinded, and the grinding time is reset, c) Start/Record; The system goes into the recording mode when key 63 is pressed. Immediately, all the manually specified -15- machine motions are recorded, and stored in memory. Here again, the graphics are updated. d) Stop/Record: The recording mode, and thus the recording of the motions specified by the user, are terminated when key 64 is pressed. The simulation module and/or teach-in module calculate the machining time, and they output the grinding time that has elapsed since the start of the program in the form of a status line. The grinding time is updated each time a machine control program line is executed. As in the collision observation, a distinction is made between the off-line mode and the on-line mode; that is, the machining time can be displayed directly or can be written into a file. The current program line and the actual position of the machine axes are also shown. As needed, machine control program lines can be input directly or indirectly by graphic manipulation. The SPS status is varied accordingly. For instance, the grinding wheel spindle or the coolant valves can be turned on and off. The status monitor of Fig. 15 shows the current status of the SPS inputs and outputs. The status of the outputs can be varied by suitable operator elements, and these changes are then transferred to the current NC program. Both the workpiece model and the machine or wheel model can be measured at any time using the mouse. In this process, points in space are selected by clicking on an area or edge whose spacing or angle from one another is displayed on the screen. A two-dimensional sectional view of the workpiece can be generated with the aid of a plane and can then be measured. The plane can be selected either arbitrarily or in terms of a peripheral condition, such as being parallel to the X axis. Thus in a section perpendicular to the longitudinal axis of the workpiece, for instance, the flute width or the effective cutting angle of the chip volume can be measured. -16- It can be expedient, if needed, to enable modeling the desired workpiece by manipulating a (swept) surface created by the motion of the grinding wheel through space. The track of the grinding wheel (swept surface) provides a volume that can be arbitrarily displaced and rotated. It is possible to restrict the displacements and rotations by means of peripheral conditions, such as displacing the volume along a coordinate axis, until this axis touches the workpiece at least one point. Other contact surfaces, such as planes, are also possible. Next, the volume can be moved a certain distance into the workpiece by a certain amount along the surface normal, so that a defined erosion depth results. In this, type of modeling, the desired machine control program is either generated entirely or completed. A virtual teach-in module for programming grinding machines or other kinds of machine tools includes a graphic user surface. This surface contains the visual display of blanks, workpieces and/or working tools. The elements shown can be displaced arbitrarily relative to one another by suitable operator elements. The resultant displacements are recorded by the virtual teach-in module and translated into a machine control program, or an existing machine control program is modified on the basis of the displacements. Various modifications to what has been described in detail above will readily occur to anyone with ordinary skill in the art. All such modifications are intended to fall within the scope of the present invention as defined by the following claims. -17- 18 We Claim 1. System (1) for the generation, modification and/or visualisation of programs for controlling grinding machines, with a teach-in module (2), which provides a visual representation of a workpiece (25) and a grinding tool and a grinding tool (27, 28, 29) on a display means (18), allows manipulation of the representation by moving the displayed workpiece (25) and the displayed grinding tool (27, 28, 29) relative to one another, and on the basis of the manipulation generates or modifies a machine control program (NC program) and displays the removal of material in model form and on the display means (18) characterized in that a means for determining the resulting workpiece dimensions on the basis of the visual representation of the virtually machined workpiece (25) by measuring the visual representation of the virtually machined workpiece (25) is provided, and that interactively usable markers are provided for the measurements, wherein points of the workpiece (25) can be randomly selected through the means, wherein the means then determines dimensional relations between the points. 2. System as claimed in claim 1, wherein the teach-in module has the following elements: 19 a memory element (17), • which is arranged to store workpiece data, which identify a workpiece in a machining state, • which is additionally arranged to store tool data, which identify a tool, and • which is arranged to store instructions, which identify one or more relative movements between the tool and workpiece, an arithmetic unit (16), which is arranged to modify the workpiece data and/or the tool data and/or data relating to the position of the workpiece and tool on the basis of the instructions in a manner corresponding to machining of the workpiece (25) by the tool (27) in accordance with the relative movement, wherein the display means (18) is arranged to provide a visual representation of the tool and the workpiece as well as its relative movement on the basis of the workpiece data and the tool data, and an input means (19), which is arranged to change the relative movement between the tool (27) and workpiece (25) to be represented by the display means and accordingly change the instructions, which identify the relative movements. 20 3. System as claimed in claim 2, wherein a transformation means is provided to transform the instructions into the machine control program (NC program). 4. System as claimed in claim 2, wherein the instructions are formed by a sequence of program commands, which form the machine control program. 5. System as claimed in claim 1, wherein the machine control program is modified during manipulation of the representation. 6. System as claimed in claim 5, wherein information or data relating to the direction, path and/or speed of a movement of the workpiece and/or the tool are changed during modification of the machine control program. 7. System as claimed in claims 2 and 3, wherein the transformation means is part of the arithmetic unit (16). 8. System as claimed in claim 2, wherein the memory means (17), the arithmetic unit (16), the display means (18) and the input means (19) are each a program or program section in association with the part of a computer used by them. 9. System as claimed in claim 2, wherein the input means (19) has a device (15) fitted as a manual input interface and a control panel as well as a program or a program section for operation of the device (15) and the control panel, and wherein the control panel is preferably a representation to be reproduced by a display system (14) with keypads (32) and, where necessary, display fields (23). 21 10. System as claimed in claim 9, wherein machine axes (X, X', Z, C) are assigned to Individual keypads. 11. System as claimed in claim 9, wherein keypads (32) are provided, to which configurable axes (K) can be assigned, which determine a movement comprising several machine axis movements. 12. System as claimed in claim 2, wherein the memory means (17) comprises a library, which contains the data of one or more blanks as well as data, which identify one or more tools. 13. System as claimed in claim 2, wherein the display means comprises an SPS status monitor, which visualises the present status of all inputs and outputs of the machine control program (SPS). 14. System as claimed in claim 1, wherein the system additionally comprises a simulation module, which provides a visual representation of a machining process, which corresponds to an existing machine control program and which is represented by a removal of material on the workpiece. 15. System as claimed in claim 14, wherein the simulation module is a part of the teach-in module. 16. System as claimed in claim 14, wherein the simulation module has a keypad which is preferably a representation to be reproduced by a display system (14) with keypads and, where necessity, display fields. 22 17. System as claimed in claim 14, wherein the simulation module permits interruption, repetition, acceleration, deceleration of the simulation or step-by step display. 18. System as claimed in claim 1 or 14, wherein the visual representation is limited to the tool and the workpiece or the machine room is included. 19. System as claimed in claim 1, comprising a collision calculation module. 20. System as claimed in claim 1, comprising a time calculation module (2b). 21. System as claimed in claim 1 or 14, wherein the system is part of a grinding machine. DATED THIS 5TH DAY OF JANUARY 2000 A virtual teach-in module for programming grinding machines or other kinds of machine tools includes a graphic user surface. This surface includes the visual display of blanks, workpieces and tools. The elements shown can be displaced arbitrarily relative to one another by means of suitable operator elements. The resultant displacements are recorded by the virtual teach-in module and converted into a machine control program, or an existing machine control program is varied based on the displacements.

Full Text

VIRTUAL TEACH-IN SYSTEM
FIELD OF THE INVENTION
The invention relates in general to a system for generating, varying and/or displaying programs for machine control. In particular, the invention relates to a system for generating, varying and/or displaying programs for controlling grinding machines.
BACKGROUND OF THE INVENTION
Machine tools are as a rule program-controlled in that machining operations which are to be performed on a workpiece proceed under program control. To generate a relative motion between the tool and the workpiece, a plurality of NC axes are provided. For example, a grinding head is supported on a suitable linear guide, which in turn is provided with an NC (numerically controlled) drive mechanism. Actuating one or more such axes creates a positioning motion. In grinding spiral grooves on drilling tools, for instance, a plurality of motion components must be superimposed in order to achieve a suitable relative motion between the workpiece and the tool.
Numerically controlled machine tools, and control programs for them, are known. European Patent Disclosure EP 0 530 364 A1, for example, discloses an interactive numerical control that produces a display of a workpiece on a monitor on the basis of existing NC data. An interactive variation of the NC data can be displayed directly. Effects of data changes are thus made immediately visible. The system includes storage means, calculation means, display means and input means. From the - display of the machining process on a monitor, the NC data can be corrected directly on the screen.
Programming NC machines demands certain skills, both in the programming language used and in terms of the special
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conditions involved in machining certain surfaces of the
workpiece.
SUMMARY OF THE INVENTION It is an object of the invention to make it easier to
operate NC machines.
This and other objects of the invention are attained by a system that has a teach-in module, which can be formed by a program running on suitable hardware, for instance. The teach-in module allows a visual, preferably three-dimensional display of a workpiece and a working tool. This is possible even if a machine control program of any kind is not yet available. Presume, for example, that it is desired to form a machined tool from a workpiece. A blank, or an incompletely machined tool, is then displayed as the workpiece. The blank or the partially machined tool can be electronically stored in a memory and then retrieved from the memory, for example. Alternatively, the teach-in module may be provided with the capability of putting together blanks or starting bodies for producing machined tools from simple geometric shapes, such as cylinders, parallelepipeds, cubes, or the like. The teach-in module can be provided with suitable scaling functions, so that the working tools, blanks or basic bodies can be displayed visually in a desired size and with a required dimensional ratio.
The teach-in module is arranged to display an operator-specified motion of the workpiece and the working tool relative to one another in response to suitable manual inputs. The motions can be input as single motion steps, for, instance, or as motions that follow a predetermined path. Specifying a path can be done for instance using typical paths, such as straight lines, helical lines, or similar courses, that are stored in a memory. Once again, a scaling function may be provided. It is also considered expedient to enable either incremental positioning or
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input of a motion path. Smoothing functions can be introduced via a manually input path.
One component of the teach-in module is that a machine control program is generated or modified on the basis of the relative motion which is input into the teach-in module, between a display of the working tool and a display of the workpiece. While the teach-in module is displaying the machining progress resulting from the relative motion between the workpiece and the working tool, or in other words is displaying the recesses generated virtually on the blank, for instance by means of a grinding wheel, the machine control data that correspond to such a machining operation are generated at the same time. In this way, the machine control program can be generated by virtual teaching-in. If the machine control program already exists, then it can be modified by the virtual teach-in method. This simplifies the operation of a corresponding numerically controlled machine tool considerably. It makes it possible in a simple manner to manipulate machine control programs, which describe not only the motion sequence but also the speeds of the axes of a grinding machine as well as status changes at the inputs of a control unit, such as an SPS control unit (for instance, turning the coolant valves or the grinding wheel spindle on and off). As a rule, such machine control programs comprise not only arranging individual commands regarding single motions of the machine axes but also SPS control commands. Program lines and program blocks made up of a plurality of program lines control the motion of one or more axes between two points in space. The virtual teach-in module now makes it possible for instance to vary existing program lines, or existing blocks composed of a plurality of program lines, to add new program lines or blocks, and to delete existing program lines or blocks.
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To that end, the virtual teach-in module preferably has a storage means, which is arranged for storing in a memory tool data and operating instructions about the relative motions between the working tool and workpiece. To that end, a memory present in hardware form, for instance, is put under the control of a suitable program or program section, which is executed on a suitable computer. The computer also includes a calculation means, to which a corresponding program section and the hardware that runs that program or program section belong. The calculation means processes the work instructions that are present in and furnished by the storage means, so as to change or add to the workpiece data and/or tool data in accordance with the work instructions, as appropriate for machining of the workpiece by the tool in accordance with the relative motion defined by the work instructions. In this way, a material erosion, for instance, and/or optionally tool wear as well, can be modeled. This is displayed by the display means, which includes a display device and the corresponding program, which serves to make data graphically visible on the display device. An input means serves to detect desired relative motions between working tool and workpiece, which are converted into corresponding work instructions, which in turn are stored or buffer-stored in memory by the storage means. The input means can include input devices and a playback device, on which "virtual input keys or the like can be shown.
In an advantageous embodiment, a transformation means is also present which converts the work instructions generated as above into a machine control program. Alternatively, the work instructions can correspond directly to a machine control program, in which case transformation can be dispensed with.
In the manipulation of the display provided by the virtual teach-in module, the machine control program is generated and/or varied. This can include both the above-described qualitative
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actions and changes in the machine control program and also changes in the data that are assigned to individual parts of the program.
The input means, which is formed for instance, by a special input device, or an input device in conjunction with input panels shown on a screen, can include both operator panels associated with individual machine axes and operator panels for configurable axes that do not match the machine axes. This makes operation even simpler.
the teach-in module can be contained in or connected to a simulation module, which allows the machining that has been input to be shown in the manner of a motion-picture film. In an advantageous embodiment, the simulation can also be performed either incrementally or in slow motion or in time-lapse form, as needed. The simulation can be interrupted and can be corrected by the teach-in module, if that should be necessary.
It can also be advantageous to provide a means with which the resultant workpiece dimensions can be determined from the visual display. Such means can for instance be a cursor, with which points of the workpiece can be selected or addressed arbitrarily, in which case this means determines dimensional relationships between the points.
The view shown by the display means is preferably a three-dimensional display, which provides the viewer with a three-dimensional impression of the virtually created workpiece. The system of the invention can either be operated on a separate computer or be integrated with the controller of an NC machine, for instance. In the first instance, NC programs for NC machines can be set up interactively, after which the program thus set up is transferred to the otherwise conventional NC machine. Data storage media or data lines can be used for this purpose.
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BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Fig. 1 shows a general block diagram of a system for generating, varying and/or displaying machine control programs;
Fig. 2 shows a general block diagram of the teach-in module of Fig. 1;
Fig. 3 shows the data flow of the teach-in module depicted in the form of a block circuit diagram;
Fig. 4 shows an element of the working tool set in a schematic illustration;
Fig. 5 shows a grinding machine and both a real and a
configurable axis in a schematic plan view;
Fig. 6 shows an operator panel for inputting desired relative motions between the virtual working tool and the virtual workpiece;
Figs. 7-9 are each a screen display of the virtual working tool and the virtual workpiece when the motion is being input;
Fig. 10 is a screen display of the working tool and workpiece when desired machining operations are being input;
Fig. 11 is a screen display of the machine for performing the machining operations of Figs. 7-10;
Fig. 12 shows an operator panel for the simulation module;
Fig. 13 is a screen display during the course of simulation;
Fig. 14 shows an expanded view of a portion of the screen display of Fig. 13; and
Fig. 15 shows the screen display of an SPS monitor.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Fig. 1 shows a teach-in system 1, which serves to generate, vary and display programs for machine control. The system 1 has a teach-in module 2, which is used to set up machine control programs interactively. The teach-in module 2 includes a computer program and the underlying hardware. It has a program part 4, which is arranged to act on data, schematically
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characterized by a block 5 in Fig. 1, and on a machine control program. The teach-in module has a collision module 2a, seen in Fig. 3, and a time calculation module 2b. The collision module 2a serves to detect undesired collisions between tool and workpiece, that is, collisions that do not constitute contact in the sense of (metal-cutting) workpiece machining. The time calculation module 2b serves to determine the machining time that will result when the machine control program is actually executed.
The data can be delivered to the teach-in module 2 from a block 6, which can for example contain data that form a picture of an unmachined workpiece. Once the initial data have been transferred from block 6 to block 5, they are applied by the teach-in module 2 for display and manipulation of the display. On the basis of the manipulation of the display, action is exerted in turn on the data in block 5 and the machine program in program part 4 again, until the desired data set and machine program have been generated. This is then output as a machine control program, as repre ented in Fig. 1 by a block 7.
As shown in Fig. 2, the teach-in module 2 includes not only a computer with a control and processing unit, which forms an arithmetic unit 11, but also a memory 12, a monitor 14, and an input device 15. The memory 12, with a section of a program 16 running on the arithmetic unit 11, forms a memory unit 17 for storing workpiece data, tool data, and instructions that characterize a relative motion between the tool and workpiece. A further section of the program 16, together with the monitor 14, forms a display means 18 for displaying the workpiece, the tool, and the motion of workpiece and tool relative to one another. Operating the teach-in system is done via a further section of the program 16 in combination with the input device 15 and the monitor 14. The applicable program section, together with the
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input device 15 and the monitor 14, forms an input means 19. The teach-in system 1 described thus far functions as follows.
As an example, it will be assumed for now that there is not yet any machine control program. Data transferred from block 6 to the teach-in module 2 therefore describe a workpiece in the unmachined state, plus at least one selected working tool. This working tool is shown on the monitor 14, together with the workpiece from block 4, by the display means 18. With the input device, motions in the display of the workpiece and/or of the tool are now specified. SPS control commands can be input or specified as well. These include turning coolant valves on and off, for instance. Moving the displays and inputting of the SPS control commands can be done from a keyboard, but is preferably done by inputs using a joystick or mouse, in conjunction with an input menu or other displays shown on the monitor 14 . The motions that result are recorded as data and converted into control instructions for an NC machine. In this way, a machine control program is created in block 5, step by step. Once the workpiece and tool have run through all the desired positions, the teach-in operation is ended, and in block 7 the finished machine control program, defined in a sense by the track of the relative motion of the workpiece display and tool display, is output. The machine control program can now be transferred directly to a machine tool, which then executes it.
Depending on the machine kinematics (axis arrangement) of the machine tool on which the program is to be executed, and depending on the machine geometry, suitable data can be defined in a configuration menu. Other configuration data, such as the description of the geometry and disposition of the tools (grinding wheels) and the geometry of the workpiece, as well as the chucking means, can: be specified from outside, via interfaces. For example, these can be written-in using data
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storage media. The data to be written-in, which make up an input data set, can include the following:
a) Tool data: description of the. geometry of the working tools, and especially of grinding machines used as working tools, and their position on being installed in the machine. In particular, individual, wheels can be combined into, sets of wheels, of the kind shown in Fig. 4. These data can be stored in datasets, or files, that are either on hand or can be furnished as needed. The data can also be stored in a data base that is part of the teach-in system or is used as needed.
b) -Data on the chucking means: description of the geometry
of the chucking means of the workpiece. These data can again be
stored in datasets or files, or in a data base.
c) Workpiece data: description of the geometry of the
workpiece as an unfinished part. These data will have already
been stored in datasets or files, or in a data base.
Alternatively or in addition, unfinished part geometries can be
derived from simple geometric shapes.
d) Machine control program data (if available): description of the NC program used. This program is either in the form of a dataset or file, or can be transferred to the teach-in system via data storage media or over a line.
e) Machine data: description of the geometry and axis configuration of the machine used.
The data that are output include:
a) Modified machine control program data: The modified or re-created machine control program is output in the form of a dataset or file. If the teach-in system is part of a machine tool, it is transferred directly to the machine controller. If the teach-in system is part of a computer located at a distance from a machine tool, then it can be transferred to the machine controller over a line or via a data storage medium.
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b) Screen: The execution and modification of the machine control program are shown graphically by material erosion on the screen. If an undesired collision occurs inside the machine, a warning can be issued and the program can be discontinued on the spot. If needed, the program line in which the collision occurred can be written into a log file.
c) Generated workpiece model: The workpiece model that has been generated can be transferred to a CAD system or some other system, for further processing.
To further illustrate the operation of the virtual teach-in system, Fig. 3 schematically shows the data flow of the system. Only one program section is shown. The communication of the virtual teach-in system with other system components, and starting the system operation, are done by a higher-order program that is not described herein nor shown in the drawings since details thereof are well known and not deemed necessary here. This also includes transferring the generated machine control program to the machine.
From an existing machine control program, which may even still be fragmentary, in a hard disk memory or from a machine control program arriving as a continuous data stream, displacement paths of machine axes are generated in a processing module 16. In Fig. 3, this is shown for five different axes X, Y, Z, A and C. The processing module also receives data about the machine geometry and kinematics, the wheel geometry, the chucking means, and the workpiece geometry. It is also connected to the input 19 means with which the user can perform an operation, interrupt or continue the processing, and add, delete or modify program lines or blocks in a targeted way as needed. From these data, the processing module sets up a workpiece model, carries out a collision observation, and calculates the machining time required. This calculation, along with the collision observation and the workpiece model, are displayed by the display
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means 18. The displacement paths generated by processing module 16 are transferred to the memory unit 17 and thus recorded on the hard disk. They can be transferred to the machine in the form of a machine control program or can first be transformed into a machine control program and then transferred to the machine.
The machine is schematically shown in plan view in Fig. 5. It has a machine bed 21, on which a workpiece carrier 22 is supported so as to be pivotable about a vertical axis C. The workpiece carrier 22 is also adjustable in a horizontal direction by means of a further NC axis X. It also carries a receiving device 24-for a workpiece 25, such as a drilling tool. A rotary positioning device, which represents a further NC axis A, can be provided on the receiving device 24 as needed.
In the vicinity of the workpiece carrier 22, a grinding head 26, which carries one or more grinding wheels 27, 28, 29, is also provided. As needed, the grinding head 26 is adjustable in a direction that coincides with the pivot axis of the grinding spindle by means of an NC axis Z and linearly in a direction parallel to the C axis (NC axis Y). The workpiece 25 is not linearly adjustable relative to the workpiece carrier 22. An axial motion (from the standpoint of the grinding wheels 27, 28, 29) of the workpiece 25 in the direction X can be accomplished by superimposing motions in the Z direction (motion of the grinding head) and in the X direction (motion of the workpiece carrier).
For the interactive teach-in programming of this NC machine, the virtual teach-in module whose operator panel is shown in Fig. 6 is used. The illustration shows an operator panel 31 for display by the display means 18 on a monitor 14. The operator panel 31 includes a plurality of operator keys 32 and display areas 33. The operator keys include keys X, Y, Z, A, C for selecting NC axes of the grinding machine. The keys marked "-", "+" and "E", for high-speed mode, serve to control the motion.
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The present feed increment can be adjusted in linear or angular
increments. A repeat key ReDo restores the last step, to have
been deleted. Another operator key panel UnDo deletes the last
step to have been input. For further selection of the axes, an
operator key panel K is also provided, which identifies a
configurable axis. This axis may deviate from the NC axes that
are actually present and can be assembled by superposition of the
motion of the various actually present machine axes X, Y, Z, A,
and C.
All the motions are conceived of and executed as linear
between two points in space. Changes in angular coordinates are
represented by linear angle changes. The motions of the machine
axes can be executed as either a motion of one axis or the
simultaneous motion of a plurality of axes. In the single
motion, one axis is selected and moves in accordance with the
feed rate selected and with the number of repetitions of the
incremental motions along the associated distance. The
simultaneous motion of a plurality of axes can be described as
the succession of single axis motions. The "multiaxis motion"
mode is turned on, and the axes are moved in succession to the
desired terminal point. The "multiaxis motion" mode is then
turned off again and all the (linear) motions since the
"multiaxis motion" was turned on are combined into a simultaneous
motion of all the axes involved.
Instead of combining single motions of machine axes into a
superimposed axis motion, in some case the "configurable axis"
can also be used. It is put together from the machine axes. The
configurable axis does not exist as a real axis, however. The
motion along this axis must be generated by the simultaneous
motion of one or more machine axes. In most cases, it is
expedient, to place a configurable axis in the center axis of the
workpiece. Moving the working tool {grinding wheel) parallel to
the workpiece axis is thus possible. A motion of the grinding
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wheel along this axis is thus always parallel to the longitudinal axis of the workpiece and need no longer be programmed as a combined motion of two machine axes, as can be seen from Fig. 5. The configurable axis is operated like a machine axis. In the machine control program (NC program), however, this motion is composed of the machine axes that are present.
The definition of the configurable axes is provided by a configuration dataset, or file. This configuration dataset or file can be modified via a menu. Thus the configurable axes can easily be adapted to different machine configurations or to the needs of special working tools or workpieces as well. In the process, the orientation of the particular configurable axis in space and the way in which it is coupled to the machine axes are defined.
In the movement of the wheel set and workpiece through the machine space, collisions can occur. These collisions can be classified in the following categories:
(1) collisions of the grinding wheel with the workpiece in
the high-speed mode;
(2) collision of the grinding wheel with the workpiece
carrier or chucking means and other machine parts;
(3) collision of the workpiece with machine parts or with
parts of the grinding wheel that do not perform metal-cutting
machining: and
(4) collision of the workpiece with a grinding wheel that
is not the actual wheel that performs metal-cutting machining.
Such collisions are of importance particularly whenever existing NC programs are being analyzed. The collision observation can be added during the execution of the NC program, either in single-step processing or in continuous processing. However, it is not an absolute necessity that it be turned on, and thus it represents an optimal property of the system.
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For the collision observation, two different operating modes are possible:
a) On-line mode: The graphics are shown in the collision
observation, and the material erosion is updated. If a collision
occurs, the program processing stops, and a warning is issued.
b) Off-line mode: The collision observation is performed
without graphics, and collisions are output to a log file.
The recording of desired workpiece motions is shown in Figs. 6-14. The point of departure is for instance an existing machine control program. This program can be displayed by means of a simulation run. The operator panel shown in Fig. 12, which is shown on a monitor, is used for this purpose. The result of the simulation can for instance be a workpiece view shown in Fig. 10. Optionally, the display can be switched over to the elevation view of the entire machine, as shown in Fig. 11. If the outcome of the machining is as desired, then the NC program can remain unchanged. If it is to be changed, however, then the simulation run can be interrupted at a desired point and a change to the virtual teach-in operating mode can be made. This is shown in Figs. ,13 and 14. The operator panel of Fig. 14, which is present in addition to the operator panel of Fig. 13, permits the recording of motion data of the grinding wheel and/or the workpiece. These data can be input by means of an input device, such as a joystick or mouse. Pressing the operator key 64 labeled "Record" translates the motions that have been input into one or more machine control program lines.
During the continuous simulation run (Fig. 12), the machine control program is executed continuously, and the following actions can be actuated by the user;
a) Starting or continuing the execution of the machine control program: The execution is started, or is continued after a temporary stop, by pressing key 51.
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b) Temporary stop in execution of the machine, control program: The execution is interrupted but can be continued, by-pressing key 52.
c) Terminating execution of the machine control program: The execution is terminated and can be begun again only by means of a restart, by pressing key 53.
d) Fast forward in machine control program execution: More than one program set is skipped, by pressing key 54. If desired, one, can skip to the next machining operation.
e) Fast rewind in machine control program execution: More than one program set is rewound, by pressing key 55. If desired, one can skip back to the previous machining operation. The graphics are then reset by the applicable operations, and the workpiece is displayed the way it looked when the corresponding machine control program lines were executed. The machining time is reset as well.
f) Switchover between views with and without the machine space (e.g., as shown in Fig. 11) by pressing button 56.
The single-step processing of the machine control program can be actuated by pressing the temporary-stop key 52. As shown in Fig. 13, the grinding wheel 27 remains in its current position, and the current machine control program lines and the machining time elapsed thus far are displayed. As shown in Fig. 14, the following actions can be actuated:
a) Single step forward: The next program line is executed by pressing key 61. The graphics and machining time are updated.
b) Single step back: The processing of the program is reset by one line by pressing key 62. The graphics and machining time are updated; that is, any material erosion that may exist is rescinded, and the grinding time is reset,
c) Start/Record; The system goes into the recording mode when key 63 is pressed. Immediately, all the manually specified
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machine motions are recorded, and stored in memory. Here again, the graphics are updated.
d) Stop/Record: The recording mode, and thus the recording of the motions specified by the user, are terminated when key 64 is pressed.
The simulation module and/or teach-in module calculate the machining time, and they output the grinding time that has elapsed since the start of the program in the form of a status line. The grinding time is updated each time a machine control program line is executed. As in the collision observation, a distinction is made between the off-line mode and the on-line mode; that is, the machining time can be displayed directly or can be written into a file. The current program line and the actual position of the machine axes are also shown.
As needed, machine control program lines can be input directly or indirectly by graphic manipulation. The SPS status is varied accordingly. For instance, the grinding wheel spindle or the coolant valves can be turned on and off. The status monitor of Fig. 15 shows the current status of the SPS inputs and outputs. The status of the outputs can be varied by suitable operator elements, and these changes are then transferred to the current NC program.
Both the workpiece model and the machine or wheel model can be measured at any time using the mouse. In this process, points in space are selected by clicking on an area or edge whose spacing or angle from one another is displayed on the screen. A two-dimensional sectional view of the workpiece can be generated with the aid of a plane and can then be measured. The plane can be selected either arbitrarily or in terms of a peripheral condition, such as being parallel to the X axis. Thus in a section perpendicular to the longitudinal axis of the workpiece, for instance, the flute width or the effective cutting angle of the chip volume can be measured.
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It can be expedient, if needed, to enable modeling the desired workpiece by manipulating a (swept) surface created by the motion of the grinding wheel through space. The track of the grinding wheel (swept surface) provides a volume that can be arbitrarily displaced and rotated. It is possible to restrict the displacements and rotations by means of peripheral conditions, such as displacing the volume along a coordinate axis, until this axis touches the workpiece at least one point. Other contact surfaces, such as planes, are also possible. Next, the volume can be moved a certain distance into the workpiece by a certain amount along the surface normal, so that a defined erosion depth results. In this, type of modeling, the desired machine control program is either generated entirely or completed.
A virtual teach-in module for programming grinding machines or other kinds of machine tools includes a graphic user surface. This surface contains the visual display of blanks, workpieces and/or working tools. The elements shown can be displaced arbitrarily relative to one another by suitable operator elements. The resultant displacements are recorded by the virtual teach-in module and translated into a machine control program, or an existing machine control program is modified on the basis of the displacements.
Various modifications to what has been described in detail above will readily occur to anyone with ordinary skill in the art. All such modifications are intended to fall within the scope of the present invention as defined by the following claims.
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18
We Claim
1. System (1) for the generation, modification and/or visualisation of
programs for controlling grinding machines,
with a teach-in module (2), which provides a visual representation of a workpiece (25) and a grinding tool and a grinding tool (27, 28, 29) on a display means (18), allows manipulation of the representation by moving the displayed workpiece (25) and the displayed grinding tool (27, 28, 29) relative to one another, and on the basis of the manipulation generates or modifies a machine control program (NC program) and displays the removal of material in model form and on the display means (18)
characterized in that a means for determining the resulting workpiece dimensions on the basis of the visual representation of the virtually machined workpiece (25) by measuring the visual representation of the virtually machined workpiece (25) is provided, and
that interactively usable markers are provided for the measurements, wherein points of the workpiece (25) can be randomly selected through the means, wherein the means then determines dimensional relations between the points.
2. System as claimed in claim 1, wherein the teach-in module has the
following elements:

19 a memory element (17),
• which is arranged to store workpiece data, which identify a workpiece in a machining state,
• which is additionally arranged to store tool data, which identify a tool, and
• which is arranged to store instructions, which identify one or more relative movements between the tool and workpiece,
an arithmetic unit (16), which is arranged to modify the workpiece data and/or the tool data and/or data relating to the position of the workpiece and tool on the basis of the instructions in a manner corresponding to machining of the workpiece (25) by the tool (27) in accordance with the relative movement, wherein the display means (18) is arranged to provide a visual representation of the tool and the workpiece as well as its relative movement on the basis of the workpiece data and the tool data, and
an input means (19), which is arranged to change the relative movement between the tool (27) and workpiece (25) to be represented by the display means and accordingly change the instructions, which identify the relative movements.

20
3. System as claimed in claim 2, wherein a transformation means is provided to transform the instructions into the machine control program (NC program).
4. System as claimed in claim 2, wherein the instructions are formed by a sequence of program commands, which form the machine control program.
5. System as claimed in claim 1, wherein the machine control program is modified during manipulation of the representation.
6. System as claimed in claim 5, wherein information or data relating to the direction, path and/or speed of a movement of the workpiece and/or the tool are changed during modification of the machine control program.
7. System as claimed in claims 2 and 3, wherein the transformation means is part of the arithmetic unit (16).
8. System as claimed in claim 2, wherein the memory means (17), the arithmetic unit (16), the display means (18) and the input means (19) are each a program or program section in association with the part of a computer used by them.
9. System as claimed in claim 2, wherein the input means (19) has a device (15) fitted as a manual input interface and a control panel as well as a program or a program section for operation of the device (15) and the control panel, and wherein the control panel is preferably a representation to be reproduced by a display system (14) with keypads (32) and, where necessary, display fields (23).

21
10. System as claimed in claim 9, wherein machine axes (X, X', Z, C) are assigned to Individual keypads.
11. System as claimed in claim 9, wherein keypads (32) are provided, to which configurable axes (K) can be assigned, which determine a movement comprising several machine axis movements.
12. System as claimed in claim 2, wherein the memory means (17) comprises a library, which contains the data of one or more blanks as well as data, which identify one or more tools.
13. System as claimed in claim 2, wherein the display means comprises an SPS status monitor, which visualises the present status of all inputs and outputs of the machine control program (SPS).
14. System as claimed in claim 1, wherein the system additionally comprises a simulation module, which provides a visual representation of a machining process, which corresponds to an existing machine control program and which is represented by a removal of material on the workpiece.
15. System as claimed in claim 14, wherein the simulation module is a part of the teach-in module.
16. System as claimed in claim 14, wherein the simulation module has a keypad which is preferably a representation to be reproduced by a display system (14) with keypads and, where necessity, display fields.

22
17. System as claimed in claim 14, wherein the simulation module permits interruption, repetition, acceleration, deceleration of the simulation or step-by step display.
18. System as claimed in claim 1 or 14, wherein the visual representation is limited to the tool and the workpiece or the machine room is included.
19. System as claimed in claim 1, comprising a collision calculation module.
20. System as claimed in claim 1, comprising a time calculation module (2b).
21. System as claimed in claim 1 or 14, wherein the system is part of a grinding machine.
DATED THIS 5TH DAY OF JANUARY 2000
A virtual teach-in module for programming grinding machines or other kinds of machine tools includes a graphic user surface. This surface includes the visual display of blanks, workpieces and tools. The elements shown can be displaced arbitrarily relative to one another by means of suitable operator elements. The resultant displacements are recorded by the virtual teach-in module and converted into a machine control program, or an existing machine control program is varied based on the displacements.

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Patent Number

212113

Indian Patent Application Number

006/CAL/2000

PG Journal Number

47/2007

Publication Date

23-Nov-2007

Grant Date

20-Nov-2007

Date of Filing

05-Jan-2000

Name of Patentee

WALTER MASCHINENBAU GMBH.

Applicant Address

DERENDINGER STRASSE 53, 72072, TUBINGEN, GERMANY.

Inventors:

#	Inventor's Name	Inventor's Address
1	DILGER CHRISTIAN	HIRSCHSTRASSE 43, D-70771, LEINFELDEN-ECHTERDINGEN
2	HUBEN FRIEDER	OTTO-HAHN-STRASSE 9/2, D-72116, MOESSINGEN

PCT International Classification Number

G05B 19/409

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	199 00 117.0	1999-01-05	Germany