Title of Invention	GEAR TOOTH CHAMFERING AND ROUNDING MACHINE
Abstract	Disclosed herewith is a chamfering and rounding machine particularly for production of internal and external chamfering and rounding to already produce gears. The machine motions are carried out by linear movement of the tool and work piece perpendicular to each other. The machine also includes tool support i.e. cutter head in which the chamfering or rounding tool is mounted which is rotatably adjustable for controlling the angular orientation of the chamfering tool. A control system including a computer controls the linear movements, angularly adjustable tool support movements as well as the necessary timed rotations of the tool and work piece.

Title of Invention

GEAR TOOTH CHAMFERING AND ROUNDING MACHINE

Abstract

Disclosed herewith is a chamfering and rounding machine particularly for production of internal and external chamfering and rounding to already produce gears. The machine motions are carried out by linear movement of the tool and work piece perpendicular to each other. The machine also includes tool support i.e. cutter head in which the chamfering or rounding tool is mounted which is rotatably adjustable for controlling the angular orientation of the chamfering tool. A control system including a computer controls the linear movements, angularly adjustable tool support movements as well as the necessary timed rotations of the tool and work piece.

Full Text	THE PATENTS ACT 1970 COMPLETE SPECIFICATION SECTION-10 TITLE GEAR TOOTH CHAMFERING AND ROUNDING MACHINE APPLICANT Premier Limited 58, Nariman Bhavan Nariman Point Mumbai - 400 021 The following specification particularly describes and ascertains the nature of the invention and the manner in which it is to be performed FIELD OF INVENTION: The present invention is directed to gear tooth chamfering and rounding machine and in particular to those machines which form chamfering and rounding to the gears already made by hobbing process utilizing tool having shape of end-mill cutter and pencil type cutter. BACKGROUND OF THE INVENTION: In the chamfering process rotating generally end-mill shaped tools are brought into contact with a work piece generally for a gear already formed by hobbing process, which is stationary. Twin spindle head in which chamfering tools are mounted are driven by A.C induction motor. Two cutters remove the stock material, one from right flank of gear and one from left flank of gear. The cutter head is swiveled to the half of the required included angle per face. After completion of one tooth, work face mounted on work head slide moves backward. Work piece is then indexed by on tooth. This indexing is obtained by controlled movement through timing belt mechanism. After indexing by one tooth work piece brought forward rapidly and then in feed to the required depth, which results contact between work piece and chamfering tool. In rounding process, instead of twin spindle head single pencil cutter is directed mounted in cutter head spindle with tool holding adaptor. Rounding of tooth is achieved by interpolation of X, & Z-axis. Interpolation on cutter movement (X-axis), work piece indexing (C-axis) and work piece linear movement (Z-axis). After completion of rounding one tooth, work piece slide moves backward and indexing by one tooth and brought forward for interpolation. This cycle repeats till all teeth on work piece are rounded. Over the years there are many approaches for chamfering and rounding of gears one vary common approach utilizes a linear slide for cutter head. The feed to the cutter is given by hydraulic for chamfering. In this mechanism work piece is stationary after indexing by one tooth. The chamfering tools are given feed to generate chamfer on tooth. Some of the chamfering machine uses to separate cutter heads, which removes the stock one from right flank of the gear and other from left flank of the gear. Individual cutter head has five manual controlled adjustments, which requires precise setting, and it was time consuming for setting. For rounding of gear tooth, rounding is obtained by coordinating the alternative movement of the cutter and rotary movement of work piece. The alternative movement of the cutter is obtained by rotation of cam, shaped in order to obtain radius or cusp rounding. A set of 4 cams allows working modulus from 1 to 16 inclusive. A regulation device allows changing modulus between minimum and maximum value of every cam. Work piece rotation is driven by 3 gears, which make the dividing system. The clamping of work piece and tool quick approach is driving by pneumatic equipment. Practical ness and quickness of setting the large choice of profiles offered by cams, and the possibility to work internal gears make the machine universal and suitable to work either small or big series. On prior art, gear chamfering machine work piece indexing is through indexing change gear and feed to the work head is by cam movement. The whole process required more time for setting, also the number of component assembled for machine are being a conventional machine. Some international publications such as JP2003251527, JP06238516, EP0522448, JP04013517, JP07016685, JP01246014 etc discloses different tooth formation and chamfer apparatuses for the gears. The dove tail type guide ways which are exposed to chips and swarf leading to deterioration as these slide way are located in a position which is very difficult to protect invention to provide a gear tooth chamfering and rounding machine of greatly simplified structure where stated drawbacks of a prior conventional machine are substantially eliminated. SUMMARY OF THE INVENTION: Various embodiments of the present invention can significantly improve upon existing machines. In some exemplary embodiments of the present invention, one or more of any above and / or other problems with existing systems can be overcome. Such as herein disclosed there is provided a gear tooth chamfering and rounding machine for producing chamfering and rounding to external and internal gears which are produced by gear hobbing or gear shaping process. The inventive machine comprise a machine bed, having a work head, comprising work piece holding fixture, work piece-indexing mechanism and hydraulically operated clamping devices. The work head moves upon linear motion guide ways positioned across the machine bed. The work head contains the work spindle and work drive mechanism for indexing/ rotating the work piece about its own longitudinal axis. The work head movement is controlled by A.C servo motor and for its positioning by precision ground ball screw. Drive to the ball screw is through coupling. The rapid travel rate for work head axis is more to reduce the auxiliary time during non-cutting period. The work piece indexing and rotation is controlled by AC servomotor through timing belt and pulley arrangement. The feed back system is used for AC servomotor is built in encoder mounted on motor. Work piece holding mechanism is by hydraulically operated cylinder. It is a double acting cylinder for clamping and de-clamping of work piece with a high pressure. A control means such as computerized system for example computer numerical control (CNC) or equivalent electronic calculating means appropriate controllable drive unit such as electrically powered motors to provide the necessary linear and rotational movements refer to above. With the machine of the present invention, the difficulties and in accuracies refer to above are eliminated. Resulting in a more precise, structurally sound and strip machine, i.e mechanically simpler than the gear tooth chamfering and rounding machine of the prior art. BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention: Fig (1a and 1b) schematically illustrates the preferred embodiment of the present invention. Fig 2 illustrates the linear (X) axes lay out of the chamfering and rounding machine according to the present invention; Fig 3 illustrates the rotational (Z) axes lay out of the chamfering and rounding machine according to the present invention; Fig 4 schematically illustrates the drive chain for the rotational (Z) axes motions according to the present invention; Fig 5 schematically illustrates the drive chain for the linear (X) axes motions according to the present invention; Fig 6 schematically illustrates the drive chain for the (C) axes motions according to the present invention; Fig 7 schematically illustrates the drive chain for cutter according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT: The present invention will now be discussed with reference to the accompanying drawing. The preferred embodiment of the present invention is shown in fig 1(a) and 1(b). The inventive gear tooth chamfering machine comprises a cutter head and work head located on a generally "L" shape type machine bed which is mounded on leveling wedges. As per one aspect of the present invention the machine for providing chamfering and rounding to the gears said machine comprising of a a work piece support means comprising means for releasably securing a work piece for rotation about an axis of rotation of said work piece and a rotatable cutter head. The rotatable cutter head mounted on linearly movable, non rotatable work head slide said cutter head having an axis of rotation, said rotatable cutter head comprising means for releasable securing a chamfering tool for rotation about an axis of rotation of said chamfering tool. The machine is also provided with a mechanism wherein the said chamfering tool and said work piece support are movable relative to one another in a direction along an X-axis and also the said chamfering tool and said work piece support are movable relative to one another in a direction along a Z-axis. The Z & X axes are mutually perpendicular and said chamfering tool and work piece support being substantially simultaneously movable along X & Z axes, the relative movement of said chamfering tool and said work piece support being controlled by control means. The cutter head slide base which is mounted along the width of the bed and a work head slide base which is mounted along the length of the bed and perpendicular to the cutter head slide base. The relative movement of the chamfering tool and the work piese are controller by electronic means from outside such as CNC etc. As shown in Fig (2) a cutter head slide mounted on a cutter head slide base through a LM guide ways for linear movement along the width of the machine bed. The motion with respect to work piece is labelled with X-axis if machine motion. A servomotor coupled to the cutter head slide via coupling, ball screw and ball screw nut for the linear movement of the cutter head. A swivel housing is mounted on cutter head slide. In a swivel housing, worm and worm wheel mechanism is provided for cutter head swivel for the required angle. The swiveling angle is half of the included chamfering angle on work piece. As per another aspect of the present invention the disclosed chamfering machine for forming chamfer and round to already produced gears, said machine can comprise of a machine bed "preferably said bed is in "L" type shape" wherein there is provided a work head located on said machine bed. The said work head is movable in direction along said base and the work head includes a means for mounting a work piece for rotation about an axis of rotation of said work-piece. Further the chamfering machine also comprise of a cutter head slide located on the said machine bed. The cutter head slide is movable along a said base in a direction substantially perpendicular to the direction of the work head, and the cutter head is located thereon, said cutter head is movable in a direction substantially perpendicular to the direction of work head. The cutter head slide has a twin spindle head. The twin spindle head comprises of a means for mounting of chamfering tools for rotation about an axis of rotation of said chamfering tool. The chamfering machine also comprises of means for controlling the movement of cutter head slide in a direction along X axis and means for controlling the movement of said work head in a direction along Z axis. The X and Z axis are mutually perpendicular, simultaneously movable with respect to each other. A cutter head, is mounted on a swiveling plate. On a cutter head, a AC induction motor is mounted. The drive to the cutters is through V pulleys and V Belt via Twin Spindle Head. The end mill cutters are mounted in Twin Spindle Head. The Center Distance is adjusted as per work piece. One of the end mill cutters is used for chamfering left flank of the gear and other is for right flank of the gear. The chamfering tool is an end mill cutter and pencil type cutter for rounding operation. The chamfer machine also comprises of a tool-clamping means and further includes tool mounting fixture Gear positioning unit is mounted on work head housing for initial position of gear. This positioning unit is necessary to used for every work piece at the time of loading of component at the fixture. Interlock system is used to avoid accident during operation. The chamfer machine as disclosed also comprises cutter head housing unit, the cutter head moves upon linear motion guide ways position across the machine bed, which is perpendicular to the work head axis. The work head movement is controlled by A.C servomotor and its position is controlled by precision ball screw. Drive to ball through coupling. The cutter head contains cutter head spindle and drive mechanism for rotation of chamfering and rounding tool about its own longitudinal axis. The rotation is controlled by A.C induction motor. The cutter head is rotatable in an angle between -15° to 60° w.r.t cutter head slide movement i.e X axis. The cutting speed is controlled by variable frequent drive to get variable revolutions per minutes. Cutter head also contains twin spindle cutter head in which two end-mill cutters are mounted. The swiveling arrangement for the cutter head is provided through worm and worm wheel mechanism. The chamfering tool is also driven by a motor located behind the cutter head housing. As shown in fig (3) a work head slide mounted on work head slide base through a LM guide ways for linear movement along the length of the machine bed. This motion with respect to cutter head is labeled the Z-axis of machine motion. A servomotor is coupled to the work head slide via coupling, ball screw and ball screw nut for the linear movement of the work head. For the work piece indexing a servomotor is mounted on the top of the work head. Through the timer pulley and timing belt, the spindle is rotated. On the front face of the spindle, a fixture for work piece is mounted. Thus the work piece is indexed. This motion is labeled as C-axis of the machine motion. The work piece indexing is dependent on the number of teeth on the work piece. Alternate embodiment of the present invention includes fix position of cutter head. The X-axis and Z-axis movement done by workhead. The Z-axis saddle movement is takes through LM guide ways and over the saddle X-axis movement is takes through LM guides. Both X-axis and Z-axis movement is perpendicular to each other. Another alternative embodiment includes the vertical movement of cutter head through LM guide ways X- axis and Z-axis movement done by work head. The Z-axis saddle movement is takes through LM guide ways and over the saddle Z-axis movement is takes through LM guides. Both X-axis and Z-axis movement is perpendicular to each other. The present invention represent an advance over machines of the prior art by providing a mechanically stiffer machine exhibiting improved dynamic characteristics and yet one which is less costly to produce. The need of individual cutter setting is eliminated. The inventive machine can be made more reliable than the chamfering and rounding machine of the prior art. The absence of individual cutter setting will results in greater reliability since this individual cutter setting is not present in the inventive chamfering and rounding machine, the problem associated therewith are also eliminated are reliability is enhanced. As per another exemplary embodiment of the present invention the machine for a chamfering and rounding to already produce a gear by chamfering and rounding process, said machine comprises of a releasable mounting of a chamfering tool for rotation about an axis of rotation of said cutter head axis. A work piece support means for releasable mounting and work piece for rotation about an axis of rotation of said work piece. The machine also comprises of means for controlling the relative rotation of said chamfering tool and said work piece in a timed relationship and means for moving said cutter-mounting means and said work piece support means relative to one another; wherein the cutter mounting means being is on a linearly movable, rotatable axial slide, the cutter mounting means is rotatable whereby the angular position of the chamfering tool is controlled. The work piece support is linearly movable in a direction perpendicular to he direction of movement of said cutter head slide i.e. (X axis). SOME EXPLANATION IN REGARD WITH DRIVE CHAIN (Fig 4 to 7) Although the foregoing description of the present invention has been shown and described with reference to particular embodiments and applications thereof, it has been presented for purposes of illustration and description and is not intended to be exhaustive or to limit the invention to the particular embodiments and applications disclosed. It will be apparent to those having ordinary skill in the art that a number of changes, modifications, variations, or alterations to the invention as described herein may be made, none of which depart from the spirit or scope of the present invention. The particular embodiments and applications were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such changes, modifications, variations, and alterations should therefore be seen as being within the scope of the present invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled. We Claim :- 1. A machine for chamfering and rounding, to the gears said machine comprising. a work piece support means comprising means for releasably securing a work piece for rotation about an axis of rotation of said work piece; a rotatable cutter head mounted on linearly movable, non rotatable work head slide said cutter head having an axis of rotation, said rotatable cutter head comprising means for releasable securing a chamfering tool for rotation about an axis of rotation of said chamfering tool; wherein the said machine further comprising (a) means hereby said chamfering tool and said work piece support are movable relative to one another in a direction along an Z-axis, (b) means hereby said chamfering tool and said work piece support are movable relative to one another in a direction along a Z-axis; and said Z & X axes being mutually perpendicular and said chamfering tool and work piece support being substantially simultaneously movable along X & Z axes, the relative movement of said chamfering tool and said work piece support being controlled by control means. 2. The machine as claimed in claim 1 where in said control means further comprises of an electronic calculating means. 3. The machine as claimed in claim 2 wherein said electronic calculating means comprises a CNC. 4. A chamfering machine for forming chamfer and round to already produced gears, said machine comprising: a machine bed; a work head located on said machine bed, said work head being movable in direction along said base, said work head including a means for mounting a work piece for rotation about an axis of rotation of said work-piece; a cutter head slide located on said machine bed, said cutter head slide being movable along a said base in a direction substantially perpendicular to the direction of said work head, said cutter head located thereon, said cutter head being movable in a direction substantially perpendicular to the direction of work head; a twin spindle head movement on said cutter head slide, a twin spindle head comprising a means for mounting of chamfering tools for rotation about an axis of rotation of said chamfering tool; means for controlling the movement of cutter head slide in a direction along an axis X means for controlling the movement of said work head in a direction along an axis Z, said X and Z axis being mutually perpendicular, simultaneously movable with respect to each other. 5. The machine as claimed in claim 4 wherein said chamfering tool is a cutting tool i.e end mill cutter or pencil type cutter for rounding. 6. The machine as claimed in claim 4 wherein said twin spindle head is of a generally oval shape with the two chamfering tool mounting means being located at two center of said twin spindle head, which can be positioned at any center distance as per the work piece requirement. 7. The machine as claimed in claim 4 wherein said twin spindle head further includes a drive spindle located within a twin spindle head housing and driven spindle located within the cutter head housing. 8 The machine as claimed in of claim 7 further including tool-clamping means. 9. The machine as claimed in claim 7 further including tool mounting fixture. 10 The machine as claimed in claim 4 wherein said chamfering tool is driven by a motor located behind the cutter head housing. 11. The machine as claimed in claim 4 wherein said machine bed comprises a length and a width, said cutter head and said work head are being movable along said length of said machine bed. 12. The machine as claimed in claim 11 wherein a said bed is in "L" type shape. 13. The machine as claimed in claim 4 wherein a said chamfering tool is a end mill cutter and pencil type cutter for rounding operation. 14. The machine as claimed in claim 4 wherein said means for controlling includes computer numerical control. 15. The machine as claimed in claim 4 wherein a said cutter head is rotatable in an angle between -15° to 60° w.r.t cutter head slide movement i.e X axis. 16. The machine as claimed in claim 4 wherein work head includes a said slide. 17. The machine as claimed in claim 4 wherein said work head further comprises at least one work piece fixture. 18. A machine chamfering and rounding to already produced gears by chamfering and rounding process, said machine comprising. a releasable mounting of a chamfering tool for rotation about an axis of rotation of said cutter head axis; a work piece support means for releasable mounting and work piece for rotation about an axis of rotation of said work piece; means for controlling the relative rotation of said chamfering tool and said work piece in a timed relationship; means for moving said cutter-mounting means and said work piece support means relative to one another; wherein said cutter mounting means being mounted on a linearly movable, rotatable axial slide, said cutter mounting means being rotatable whereby the angular position of said chamfering tool is controlled; and said work piece support being linearly movable in a direction perpendicular to he direction of movement of said cutter head slide i.e. (X axis). ABSTRACT: GEAR TOOTH CHAMFERING AND ROUNDING MACHINE Disclosed herewith is a chamfering and rounding machine particularly for production of internal and external chamfering and rounding to already produce gears. The machine motions are carried out by linear movement of the tool and work piece perpendicular to each other. The machine also includes tool support i.e. cutter head in which the chamfering or rounding tool is mounted which is rotatably adjustable for controlling the angular orientation of the chamfering tool. A control system including a computer controls the linear movements, angularly adjustable tool support movements as well as the necessary timed rotations of the tool and work piece. Fig 1(a)

Full Text

THE PATENTS ACT 1970
COMPLETE
SPECIFICATION
SECTION-10
TITLE
GEAR TOOTH CHAMFERING AND ROUNDING MACHINE
APPLICANT
Premier Limited
58, Nariman Bhavan
Nariman Point Mumbai - 400 021
The following specification particularly describes and ascertains the nature of the invention and the manner in which it is to be performed

FIELD OF INVENTION:
The present invention is directed to gear tooth chamfering and rounding machine and in particular to those machines which form chamfering and rounding to the gears already made by hobbing process utilizing tool having shape of end-mill cutter and pencil type cutter.
BACKGROUND OF THE INVENTION:
In the chamfering process rotating generally end-mill shaped tools are brought into contact with a work piece generally for a gear already formed by hobbing process, which is stationary. Twin spindle head in which chamfering tools are mounted are driven by A.C induction motor. Two cutters remove the stock material, one from right flank of gear and one from left flank of gear.
The cutter head is swiveled to the half of the required included angle per face. After completion of one tooth, work face mounted on work head slide moves backward. Work piece is then indexed by on tooth. This indexing is obtained by controlled movement through timing belt mechanism.
After indexing by one tooth work piece brought forward rapidly and then in feed to the required depth, which results contact between work piece and chamfering tool.
In rounding process, instead of twin spindle head single pencil cutter is directed mounted in cutter head spindle with tool holding adaptor. Rounding of tooth is achieved by interpolation of X, & Z-axis. Interpolation on cutter movement (X-axis), work piece indexing (C-axis) and work piece linear movement (Z-axis). After completion of rounding one tooth, work piece slide moves backward and indexing by one tooth and brought forward for interpolation. This cycle repeats till all teeth on work piece are rounded.

Over the years there are many approaches for chamfering and rounding of gears one vary common approach utilizes a linear slide for cutter head. The feed to the cutter is given by hydraulic for chamfering. In this mechanism work piece is stationary after indexing by one tooth. The chamfering tools are given feed to generate chamfer on tooth.
Some of the chamfering machine uses to separate cutter heads, which removes the stock one from right flank of the gear and other from left flank of the gear. Individual cutter head has five manual controlled adjustments, which requires precise setting, and it was time consuming for setting.
For rounding of gear tooth, rounding is obtained by coordinating the alternative movement of the cutter and rotary movement of work piece.
The alternative movement of the cutter is obtained by rotation of cam, shaped in order to obtain radius or cusp rounding. A set of 4 cams allows working modulus from 1 to 16 inclusive.
A regulation device allows changing modulus between minimum and maximum value of every cam.
Work piece rotation is driven by 3 gears, which make the dividing system. The clamping of work piece and tool quick approach is driving by pneumatic equipment. Practical ness and quickness of setting the large choice of profiles offered by cams, and the possibility to work internal gears make the machine universal and suitable to work either small or big series.
On prior art, gear chamfering machine work piece indexing is through indexing change gear and feed to the work head is by cam movement. The whole process required more time for setting, also the number of component

assembled for machine are being a conventional machine. Some international publications such as JP2003251527, JP06238516, EP0522448, JP04013517, JP07016685, JP01246014 etc discloses different tooth formation and chamfer apparatuses for the gears. The dove tail type guide ways which are exposed to chips and swarf leading to deterioration as these slide way are located in a position which is very difficult to protect invention to provide a gear tooth chamfering and rounding machine of greatly simplified structure where stated drawbacks of a prior conventional machine are substantially eliminated.
SUMMARY OF THE INVENTION:
Various embodiments of the present invention can significantly improve upon existing machines. In some exemplary embodiments of the present invention, one or more of any above and / or other problems with existing systems can be overcome. Such as herein disclosed there is provided a gear tooth chamfering and rounding machine for producing chamfering and rounding to external and internal gears which are produced by gear hobbing or gear shaping process.
The inventive machine comprise a machine bed, having a work head, comprising work piece holding fixture, work piece-indexing mechanism and hydraulically operated clamping devices. The work head moves upon linear motion guide ways positioned across the machine bed. The work head contains the work spindle and work drive mechanism for indexing/ rotating the work piece about its own longitudinal axis. The work head movement is controlled by A.C servo motor and for its positioning by precision ground ball screw. Drive to the ball screw is through coupling. The rapid travel rate for work head axis is more to reduce the auxiliary time during non-cutting period.
The work piece indexing and rotation is controlled by AC servomotor through timing belt and pulley arrangement. The feed back system is used for AC servomotor is built in encoder mounted on motor. Work piece holding

mechanism is by hydraulically operated cylinder. It is a double acting cylinder for clamping and de-clamping of work piece with a high pressure.
A control means such as computerized system for example computer numerical control (CNC) or equivalent electronic calculating means appropriate controllable drive unit such as electrically powered motors to provide the necessary linear and rotational movements refer to above.
With the machine of the present invention, the difficulties and in accuracies refer to above are eliminated. Resulting in a more precise, structurally sound and strip machine, i.e mechanically simpler than the gear tooth chamfering and rounding machine of the prior art.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention:
Fig (1a and 1b) schematically illustrates the preferred embodiment of the present invention.
Fig 2 illustrates the linear (X) axes lay out of the chamfering and rounding machine according to the present invention;
Fig 3 illustrates the rotational (Z) axes lay out of the chamfering and rounding machine according to the present invention;
Fig 4 schematically illustrates the drive chain for the rotational (Z) axes motions according to the present invention;

Fig 5 schematically illustrates the drive chain for the linear (X) axes motions according to the present invention;
Fig 6 schematically illustrates the drive chain for the (C) axes motions according to the present invention;
Fig 7 schematically illustrates the drive chain for cutter according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT:
The present invention will now be discussed with reference to the accompanying drawing. The preferred embodiment of the present invention is shown in fig 1(a) and 1(b). The inventive gear tooth chamfering machine comprises a cutter head and work head located on a generally "L" shape type machine bed which is mounded on leveling wedges.
As per one aspect of the present invention the machine for providing chamfering and rounding to the gears said machine comprising of a a work piece support means comprising means for releasably securing a work piece for rotation about an axis of rotation of said work piece and a rotatable cutter head.
The rotatable cutter head mounted on linearly movable, non rotatable work head slide said cutter head having an axis of rotation, said rotatable cutter head comprising means for releasable securing a chamfering tool for rotation about an axis of rotation of said chamfering tool. The machine is also provided with a mechanism wherein the said chamfering tool and said work piece support are movable relative to one another in a direction along an X-axis and also the said chamfering tool and said work piece support are movable relative to one another in a direction along a Z-axis. The Z & X axes are mutually perpendicular and said chamfering tool and work piece support being substantially simultaneously

movable along X & Z axes, the relative movement of said chamfering tool and said work piece support being controlled by control means.
The cutter head slide base which is mounted along the width of the bed and a work head slide base which is mounted along the length of the bed and perpendicular to the cutter head slide base.
The relative movement of the chamfering tool and the work piese are controller by electronic means from outside such as CNC etc.
As shown in Fig (2) a cutter head slide mounted on a cutter head slide base through a LM guide ways for linear movement along the width of the machine bed. The motion with respect to work piece is labelled with X-axis if machine motion. A servomotor coupled to the cutter head slide via coupling, ball screw and ball screw nut for the linear movement of the cutter head.
A swivel housing is mounted on cutter head slide. In a swivel housing, worm and worm wheel mechanism is provided for cutter head swivel for the required angle. The swiveling angle is half of the included chamfering angle on work piece.
As per another aspect of the present invention the disclosed chamfering machine for forming chamfer and round to already produced gears, said machine can comprise of a machine bed "preferably said bed is in "L" type shape" wherein there is provided a work head located on said machine bed. The said work head is movable in direction along said base and the work head includes a means for mounting a work piece for rotation about an axis of rotation of said work-piece.
Further the chamfering machine also comprise of a cutter head slide located on the said machine bed. The cutter head slide is movable along a said base in a direction substantially perpendicular to the direction of the work head, and the

cutter head is located thereon, said cutter head is movable in a direction substantially perpendicular to the direction of work head.
The cutter head slide has a twin spindle head. The twin spindle head comprises of a means for mounting of chamfering tools for rotation about an axis of rotation of said chamfering tool. The chamfering machine also comprises of means for controlling the movement of cutter head slide in a direction along X axis and means for controlling the movement of said work head in a direction along Z axis. The X and Z axis are mutually perpendicular, simultaneously movable with respect to each other.
A cutter head, is mounted on a swiveling plate. On a cutter head, a AC induction motor is mounted. The drive to the cutters is through V pulleys and V Belt via Twin Spindle Head. The end mill cutters are mounted in Twin Spindle Head. The Center Distance is adjusted as per work piece. One of the end mill cutters is used for chamfering left flank of the gear and other is for right flank of the gear. The chamfering tool is an end mill cutter and pencil type cutter for rounding operation. The chamfer machine also comprises of a tool-clamping means and further includes tool mounting fixture
Gear positioning unit is mounted on work head housing for initial position of gear. This positioning unit is necessary to used for every work piece at the time of loading of component at the fixture. Interlock system is used to avoid accident during operation.
The chamfer machine as disclosed also comprises cutter head housing unit, the cutter head moves upon linear motion guide ways position across the machine bed, which is perpendicular to the work head axis. The work head movement is controlled by A.C servomotor and its position is controlled by precision ball screw. Drive to ball through coupling. The cutter head contains cutter head spindle and drive mechanism for rotation of chamfering and rounding tool about its own longitudinal axis. The rotation is controlled by A.C induction motor. The

cutter head is rotatable in an angle between -15° to 60° w.r.t cutter head slide movement i.e X axis. The cutting speed is controlled by variable frequent drive to get variable revolutions per minutes. Cutter head also contains twin spindle cutter head in which two end-mill cutters are mounted. The swiveling arrangement for the cutter head is provided through worm and worm wheel mechanism. The chamfering tool is also driven by a motor located behind the cutter head housing.
As shown in fig (3) a work head slide mounted on work head slide base through a LM guide ways for linear movement along the length of the machine bed. This motion with respect to cutter head is labeled the Z-axis of machine motion. A servomotor is coupled to the work head slide via coupling, ball screw and ball screw nut for the linear movement of the work head.
For the work piece indexing a servomotor is mounted on the top of the work head. Through the timer pulley and timing belt, the spindle is rotated. On the front face of the spindle, a fixture for work piece is mounted. Thus the work piece is indexed. This motion is labeled as C-axis of the machine motion. The work piece indexing is dependent on the number of teeth on the work piece.
Alternate embodiment of the present invention includes fix position of cutter head. The X-axis and Z-axis movement done by workhead. The Z-axis saddle movement is takes through LM guide ways and over the saddle X-axis movement is takes through LM guides. Both X-axis and Z-axis movement is perpendicular to each other.
Another alternative embodiment includes the vertical movement of cutter head through LM guide ways X- axis and Z-axis movement done by work head. The Z-axis saddle movement is takes through LM guide ways and over the saddle Z-axis movement is takes through LM guides. Both X-axis and Z-axis movement is perpendicular to each other.

The present invention represent an advance over machines of the prior art by providing a mechanically stiffer machine exhibiting improved dynamic characteristics and yet one which is less costly to produce. The need of individual cutter setting is eliminated.
The inventive machine can be made more reliable than the chamfering and rounding machine of the prior art. The absence of individual cutter setting will results in greater reliability since this individual cutter setting is not present in the inventive chamfering and rounding machine, the problem associated therewith are also eliminated are reliability is enhanced.
As per another exemplary embodiment of the present invention the machine for a chamfering and rounding to already produce a gear by chamfering and rounding process, said machine comprises of a releasable mounting of a chamfering tool for rotation about an axis of rotation of said cutter head axis. A work piece support means for releasable mounting and work piece for rotation about an axis of rotation of said work piece.
The machine also comprises of means for controlling the relative rotation of said chamfering tool and said work piece in a timed relationship and means for moving said cutter-mounting means and said work piece support means relative to one another; wherein the cutter mounting means being is on a linearly movable, rotatable axial slide, the cutter mounting means is rotatable whereby the angular position of the chamfering tool is controlled. The work piece support is linearly movable in a direction perpendicular to he direction of movement of said cutter head slide i.e. (X axis).

SOME EXPLANATION IN REGARD WITH DRIVE CHAIN (Fig 4 to 7)
Although the foregoing description of the present invention has been shown and described with reference to particular embodiments and applications thereof, it has been presented for purposes of illustration and description and is not intended to be exhaustive or to limit the invention to the particular embodiments and applications disclosed. It will be apparent to those having ordinary skill in the art that a number of changes, modifications, variations, or alterations to the invention as described herein may be made, none of which depart from the spirit or scope of the present invention. The particular embodiments and applications were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such changes, modifications, variations, and alterations should therefore be seen as being within the scope of the present invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled.

We Claim :-
1. A machine for chamfering and rounding, to the gears said machine
comprising.
a work piece support means comprising means for releasably securing a work piece for rotation about an axis of rotation of said work piece;
a rotatable cutter head mounted on linearly movable, non rotatable work head slide said cutter head having an axis of rotation, said rotatable cutter head comprising means for releasable securing a chamfering tool for rotation about an axis of rotation of said chamfering tool; wherein the said machine further comprising (a) means hereby said chamfering tool and said work piece support are movable relative to one another in a direction along an Z-axis, (b) means hereby said chamfering tool and said work piece support are movable relative to one another in a direction along a Z-axis; and
said Z & X axes being mutually perpendicular and said chamfering tool and work piece support being substantially simultaneously movable along X & Z axes, the relative movement of said chamfering tool and said work piece support being controlled by control means.
2. The machine as claimed in claim 1 where in said control means further comprises of an electronic calculating means.
3. The machine as claimed in claim 2 wherein said electronic calculating means comprises a CNC.
4. A chamfering machine for forming chamfer and round to already produced gears, said machine comprising:
a machine bed;
a work head located on said machine bed, said work head being movable in direction along said base, said work head including a means for

mounting a work piece for rotation about an axis of rotation of said work-piece;
a cutter head slide located on said machine bed, said cutter head slide being movable along a said base in a direction substantially perpendicular to the direction of said work head, said cutter head located thereon, said cutter head being movable in a direction substantially perpendicular to the direction of work head;
a twin spindle head movement on said cutter head slide, a twin spindle head comprising a means for mounting of chamfering tools for rotation about an axis of rotation of said chamfering tool;
means for controlling the movement of cutter head slide in a direction along an axis X means for controlling the movement of said work head in a direction along an axis Z, said X and Z axis being mutually perpendicular, simultaneously movable with respect to each other.
5. The machine as claimed in claim 4 wherein said chamfering tool is a cutting tool i.e end mill cutter or pencil type cutter for rounding.
6. The machine as claimed in claim 4 wherein said twin spindle head is of a generally oval shape with the two chamfering tool mounting means being located at two center of said twin spindle head, which can be positioned at any center distance as per the work piece requirement.
7. The machine as claimed in claim 4 wherein said twin spindle head further includes a drive spindle located within a twin spindle head housing and driven spindle located within the cutter head housing.
8 The machine as claimed in of claim 7 further including tool-clamping
means.
9. The machine as claimed in claim 7 further including tool mounting fixture. 10 The machine as claimed in claim 4 wherein said chamfering tool is driven
by a motor located behind the cutter head housing.

11. The machine as claimed in claim 4 wherein said machine bed comprises a length and a width, said cutter head and said work head are being movable along said length of said machine bed.
12. The machine as claimed in claim 11 wherein a said bed is in "L" type shape.
13. The machine as claimed in claim 4 wherein a said chamfering tool is a end mill cutter and pencil type cutter for rounding operation.
14. The machine as claimed in claim 4 wherein said means for controlling includes computer numerical control.
15. The machine as claimed in claim 4 wherein a said cutter head is rotatable in an angle between -15° to 60° w.r.t cutter head slide movement i.e X axis.

16. The machine as claimed in claim 4 wherein work head includes a said slide.
17. The machine as claimed in claim 4 wherein said work head further comprises at least one work piece fixture.
18. A machine chamfering and rounding to already produced gears by
chamfering and rounding process, said machine comprising.
a releasable mounting of a chamfering tool for rotation about an axis of
rotation of said cutter head axis;
a work piece support means for releasable mounting and work piece for
rotation about an axis of rotation of said work piece;
means for controlling the relative rotation of said chamfering tool and said
work piece in a timed relationship;
means for moving said cutter-mounting means and said work piece
support means relative to one another; wherein
said cutter mounting means being mounted on a linearly movable,
rotatable axial slide, said cutter mounting means being rotatable whereby
the angular position of said chamfering tool is controlled; and

said work piece support being linearly movable in a direction perpendicular to he direction of movement of said cutter head slide i.e. (X axis).

ABSTRACT:
GEAR TOOTH CHAMFERING AND ROUNDING MACHINE
Disclosed herewith is a chamfering and rounding machine particularly for production of internal and external chamfering and rounding to already produce gears. The machine motions are carried out by linear movement of the tool and work piece perpendicular to each other. The machine also includes tool support i.e. cutter head in which the chamfering or rounding tool is mounted which is rotatably adjustable for controlling the angular orientation of the chamfering tool. A control system including a computer controls the linear movements, angularly adjustable tool support movements as well as the necessary timed rotations of the tool and work piece.
Fig 1(a)

GEAR TOOTH CHAMFERING AND ROUNDING MACHINE

Documents:

Inventors:

PCT Conventions: