Title of Invention

A SYSTEM FOR UNDERWINDING IN A TEXTILE RING SPINNING AND TWISTING MACHINE

Abstract

The present invention relates to a System for underwinding in a textile risng spinning andtwisting machine, comprising a plurality of spindle assemblies(9)with wharve members(7a)mounted on a ring rail assembly (4) a drive member operable connected to said ring rail assembly and driven by a control means(13a,14,15,&16)characterized in that said control means (13a,14,15,&16)disposed to position said ringrail assembly (4) at pre-determined locations of said wharve member(7a) to perform non-overlapping underwinding of the yarn on said wharve member (7a)

Full Text

A SYSTEM FOR UNDERWINDING OF YARN IN A TEXTILE RING SPINNING ' AND TWISTING MACHINE Technical Field The present invention relates to under winding in a textile ring spinning and twisting machine, particularly relates to a digitally implemented system for a non-overlapping under winding of yam on different pre-determined positions of wharves member of a ring spiiming and twisting machine. Background and prior art Ring spiiming and twisting machines are provided with plurality of spindles arranged in rows on both side of the ring spinning machine. These spindles comprising a top part, which is rotatably mounted on a bearings housed in the bolster and rigidly mounted on the spindle rails. The top part of the spindles carries conical tubes on which the yam formed by the ring spinning machine is wound to produce the desired package. Ring rails carrying ring and ring traveler assembly is arranged coaxial to the spindle axis. The ring traveler travels on the flange portion of the ring by the yam which is wound on the conical tubes. Normally, the drafted fibre delivered by the ring spiiming machine drafting system are twisted by the ring traveler and deposited on the conical tube and the package is built according to the desired fashion by the up and down travel of the ring rail with the ring traveler assembly. Once the cop built-up is completed, the cops are replaced by empty conical tubes and subsequent package is produced. Modem ring spinning machines are contacted with spindles of 1200 and above and most of such rings spinning machines are provided with auto doffer arrangement for the exchange of empty conical tubes with cops. The auto doffer replaces the cop present on the spindle with an empty conical tube. Just before the doffing few layers of yam is wound on the top end of the conical tube and the ring rail is moved to the wharves region of the spindle and 2 to 3 layers of the yam is wound on the wharves member, which is known as under winding. During the doffing operation, wound package is doffed and a fresh conical tube is re-fixed on the spindle, the ring rail is moved upwards to a position to form a new yam package on the new conical tube. The yarn leading from the under winding is thus connected to the first few windings around the new conical tube and during the next doff the length of yam connecting the under winding and the initial winding is severed In order to achieve the reserve winding otherwise known as under winding , as well as to control the movement of ring rail during the cop built up in the known machines, the ring rail movement is controlled by a cam attached to the ring rail drive mechanism. Certain modem ring spinning machines the ring rail movement is controlled by drive system comprising separate motor. At the end of cop built up, this cam or the ring rail drive system shifts the position of the ring rail to a particular position such that under winding is formed with few rotation of the yam on the wharve member of the spindle. In such known arrangement the under winding is formed at a particular location on the wharve. It leads in to the problem of over lapping of the under winding one over the other, if the under winding are not properly removed before the start of next doffing cycle. Also accumulation of unnecessary yam in the wharve results in higher power consumption. US patent 6487841 discloses a method for controlling a ring spinning frame that has a drafting unit, a spindle, and ring rail with respective drives and a clamping device in coordination with a crown is provided for under winding of yam .It is claimed such method permits relatively shorter length of yam as under winding. Though the above arrangement may perform satisfactorily, it involves spindle assembly with costly yern catching arrangement. Normally, the cutting of the leading end of the yam of the under winding is achieved by the known crown and cutter, in which the yam is guided by the crown and cut by the cutter. In the event of such over lapping of under winding the cutter will not be effective due to the fact that because of the over lapping, during the doffing the yam could not to be presented to the vicinity of the cutter. Also such arrangement employs separate crown cleaning arrangement, which is expensive. Objects of the present invention The primary object of the present invention is to provide a digitally implemented system for a non-overlapping underwinding of yam on a wharve member of a textile ring spinning and twisting machine. An object of the present invention is to provide a digitally Implemented system for a non-overlapping underwinding of yam at different pre-determined positions on wharve member of the ring spinning and twisting machine to eliminate the problem of overlapping of underwinding layers. Another object of the present invention is to provide a digitally implemented system for a non-overlapping underwinding of yarn with a Programmable Logic Controller (PLC) for actuating the movement of the ring rail to regulate the plurality of positions of the underwinding on the wharve member. Yet another object of the present invention is to provide a digitally implemented system for a non-overlapping underwinding of yam in ring spinning and twisting machine to avoid using external underwinding clearers such as abrading tools, cutting tools etc., for removing unwanted underwinding layers, or the use of expensive yam catching mechanism. Summary of the present invention The present invention provides a digitally implemented system for as non-overlapping underwinding of yam on a wharve member of a ring spinning and twisting machine. The system of the present invention comprises a wharve member, a drive member controlled by a control means. The wharve member is disposed at the bottom of a spindle assembly of the textile ring frame to permit deposition of non-overlapping underwinding of the yam subsequent to the cop build up. The control means in the form of Programmable Logic Controller (PLC) is operable connected to the ring rail assembly through the drive member for effecting perpendicular up and downward traverse motion of the ring rail and for extending the ring rail assembly to the wharve member. The control means through the drive member also executes a non-overlapping underwinding of the yam, at pre-determined positions on the wharve member, after the completion of cop built up on conical tube of the ring spinning machine and before the doffing of cop with new and empty conical tube. Brief description of the diagrams Fig. 1 schematically illustrates a cross section view of the ring spinning machine housing the system of the present invention. Fig. 2 schematically illustrates the drive arrangement of the ring rail according to this invention Fig. 3 schematically illustrates the control system of the present invention and also displays the different positions of the under windings. Fig. 4 is a schematic flow of the underwinding system of the present invention Fig 5 is a schematic flow of the PLC logic of the present invention Detailed description of the invention The embodiments of the present invention will now be explained by referring to accompanying drawings. Fig 1 illustrates a cross section view of a ring spinning and twisting machine. The roving (R) from the creel is fed through the roving guide (1) to the drafting arrangement (2), said drafting arrangement comprising drafting rollers (2a), (2b) and (2c). The drafting rollers (2a), (2b) and (2c) are provided with necessary drafting pressure by the loading arm (2d) of the drafting arrangement (2). The drafting rollers (2a), (2b) and (2c) are driven by the drafting roller drive system of the ring spinning and twisting machine at a differential speed to facilitate drafting of the roving (R). The drafted fiber emerging from said pairs of drafting roller (2c) are guided to revolving spindle (7) by revolving of ring traveler of the ring traveler assembly (3) mounted on the ring rail (4) through the lappet (5). During the process of cop build up of the machine, the yam is wound on a conical tube (6) mounted on the revolving spindle (7) of the spindle assembly (9). The vertically movable ring rail (4) is operably moved up and down in a direction parallel to the axis of the spindle assembly (9) by the ring rail drive system. The spindle assembly (9) is a conventional one comprising spindle (7) which is being rotatably supported in a bolster (8) of the spindle assembly (9) and driven by the spindle drive system of the ring spinning and twisting machine. The spindle (7) of the spindle assembly (9) comprises a wharve member (7a) at the bottom portion said wharve member (7a) is provided with knurling for the slip free deposition of the underwinding layers of yam. A plurality of wraps or underwindings of yam are formed on the wharve member (7a). The spindle assembly (9) is mounted on a spindle rail (10) and is provided with a crown (11) and a cutter (12). The invention employs the conventional crown (11) and cutter (12) for doffing operation of the conical tube (6). Now by specifically referring to Fig 2 in addition to Fig 1, a drive member of a ring rail system of the ring spinning and twisting machine is shown. The drive member comprises a motor (13) which may be a servo motor or three phase induction motor provided with suitable control means attached to said drive member. The motor (13) produces rotary motion and the drive member converts the rotary motion of the motor (13) into a corresponding linear motion of the ring rail (4). The drive member connected to the motor (13) comprises a gear box unit (GB), driver pulley (17), driven pulley (18 & 20), shaft (19), a plurality of sliders (23), slider assembly (23a), tapes (22 & 25), guide pulleys (24) and connectors (26). The motor (13) is connected to the gear box unit (GB) and is fitted on the head stock of the ring spinning and twisting machine. The driver pulley (17) is mounted on the out put shaft of the gear box unit (GB). The driven pulley (18) is mounted on the shaft (19) which is rotatably mounted on bearings and disposed on the head stock of the ring spinning and twisting machine. The driven pulley (20) is also mounted on the shaft (19). The slider assembly (23a) is arranged both on the left and right sides of the system, said assembly comprises a plurality of sliders (23), the number of sliders is equal to twice the number of sections of the ring spinning machine and twisting machine. The one end of the tape (22) is connected to the driven pulley (20) and the other end fastened to the first slider of the plurality of sliders (23) for transmitting the rotary motion of the driven pulley (20) into linear motion of the slider assembly (23a). A plurality of tapes (25) is provided for connecting the slider assembly (23a) and the ring rail bracket (not shown) on which the ring rail (4) is mounted. The ring rail bracket is slidable on vertical shafts (not shown) in a direction parallel to the axis of the spindle (7). At least two tapes (25) are provided per ring rail (4). While one end of the tape (25) is fastened to the slider (23), the other end of the tape (25) is fastened to the connector (26) provided with adjusting means. The ring rail bracket is connected to the tape (25) by means of connectors (26). A plurality of guide pulleys (24) is provided to guide the tapes (25). With this arrangement the rotary motion generated by the motor (13) is converted into up and down motion of the ring rail (4) in direction parallel to the axis of the spindle (7). The shaft (19) also carries another pulley (20) to provide the up and down movement of the ring rails (4) arranged on the other side of the ring spinning and twisting machine. The rotation of the motor (13) in one particular direction winds the tape (22) on the roller (20) and thereby the pulls the slider assembly (23a) which in turn lifts the ring rail bracket and the ring rail (4) in up ward direction. Like wise the rotation of the motor (13) in the opposite direction unwinds the tape (22) on the roller (20) and pushes the slider assembly (23a) which in turn lowers the ring rail bracket and the ring rail (4) due to the self weight of the ring rail bracket and the ring rail (4). This linear motion of the ring rail (4) causes the yam to be wound on the conical tube uniformly resulting in a built up cop. Now by referring to Fig 1& 3, at the end of the cop build up, the spindle (7) is stopped. If top bunch winding is required for subsequent usage, for example for use in the cone winding process, the ring rail (4) is moved towards a predetermined position at the top end of the conical tube (6). The spindle (7) is rotated for few revolutions and few layers of the yam are wound on the top portion of the conical tube (6) as top bunch winding. Soon after top bunching is performed, a control means, which is Programmable Logic Controller (PLC), which is operable connected to the ring rail (4) through the drive member, actuates the movement of ring rail (4) towards the wharve member (7a) of the spindle (7). The control means through the drive member executes a non-overlapping underwinding of the yam at pre-determined positions on the wharve member (7a). The spindle (7) is rotated by two to three revolutions to deposit the underwinding about the knurled wharve member (7a). The yam present between the final winding and the underwinding passes through the crown (11) and cutter (12) to facilitate severing of the yam during the doffing operation. This underwinding is performed after completion of cop built up on conical tube (6) and before the doffing. The control means includes an input device (16), a Programmable Logic Controller (PLC) (15), a motor drive unit (14) and a feedback arrangement (13a). The input device (16) is disposed to enable a user to provide an input regarding the pre¬determined positions of the underwinding of the yam on the wharve member (7a) to the Programmable Logic Controller (PLC) (15). The input device (16) can be of any conventional user interface selected from keyboard, touch-screen, and keypad etc. The programmable logic controller (15) is disposed to actuate and direct the ring rail (4) to perform a non-overlapping underwinding of the yam on the wharve member (7a) at pre-determined positions and to iterate the sequence of pre-determined positions of the underwinding. The motor drive unit (14) regulates the rotational speed of the motor (13) as per the instructions from the programmable logic controller (15). The feedback arrangement (13a) is a rotary encoder which is disposed to position the ring rail (4) at pre-determined positions on the wharve member (7a). The feed back arrangement (13a) is employed to ensure that the ring rail (4) is properly positioned at the pre determined location. The feed back device, the rotary encoder measures the rotational movement of the servo motor shaft and compares the same as equivalent linear movement of the ring rail (4). The rotary encoder produces voltage pulses corresponding to the number of revolutions of the servo motor shaft. This voltage pulse is in put to the PLC for the position control of the ring trail. The PLC compares the pre determined position and the actual position of the ring rail and effect necessary correction if there is a mismatch by varying the number of revolution of the servo motor. The working of the invention is further explained by referring to Figs 3, 4 & 5 of the accompanying diagrams. The Programmable Logic Controller (15) is programmed by means of the input device (16). The input device (16) is also referred to Human Machine Interface (HMI) which serves as a means for providing an input by a user for building the cops and selecting the first location of the plurality of underwindings on the wharve member (7a). The Programmable Logic Controller (15) provides necessary signal to a motor drive unit (14) which in turn controls the motor (13) and thereby controls the movement of the ring rail (4) for the cop built up, top bunch winding as well as under winding. The PLC (15) is initially programmed by the user by means of the input device (16), after which it provides necessary signals to the motor drive unit (14). The motor drive unit (14) is connected to the motor (13) and provides a signal to the motor and regulate its rotational speed. The motor (13) is provided with feed back arrangement (13a) which is in turn connected back to the motor drive unit (14). The PLC (15) processes the parameters and converts the same to electrical signal. This electrical signal is fed to the motor drive unit (14) which regulates the rotation of the motor (13). The rotation of the motor (13) is converted into linear motion of the ring rail by means of the drive member of ring rail assembly for effecting perpendicular up and downward traverse motion and to position said ring assembly at pre-determined positions of said wharve member. The linear position is taken as the feed back to the PLC (15) with the help of a rotary encoder (13a) which in turn controls the drive to position the ring rail (4) for effecting the under winding at the pre determined position on the wharve member (7a) of the spindle (7). The PLC (15) memorizes the previous position of the under winding and during the next doff the under winding will be done on a different position at the wharve member (7a) of the spindle (7). The non-overlapping underwinding of yam is the deposit of underwinding at pre¬determined positions on the wharve member (7a). The pre-determined position of underwinding of the yam on the wharve member (7a) is either below or above the previously formed under winding. The number of pre-determined positions for under winding of yam on the wharve member is more than 2, preferably three positions. Considering the number of pre-determined positions of the underwinding as three, underwinding takes place during doffs in the order of 1, 4, 7..., n, (where n value depends on total number of the spindles in a ring frame) at the top portion of the wharve (7a) of the spindle (7) as illustrated in the left hand side cop shown in the Fig 3. During doffs 2, 5, 8..., (n + 1) the underwinding takes place on the wharve (7a) of the spindle (7) at a portion below the underwinding effected during doffs 1, 4, 7... as illustrated in the middle cop shown in the Fig 2. During doffs 3, 6, 9,..., (n + 2) the underwinding takes place on the wharve (7a) of the spindle (7) at a portion still below the underwinding effected during doffs 2, 5, 8... as illustrated in the right hand side cop shown in the Fig 3. In the preferred embodiment there are 3 different pre-defined positions and the under winding will repeat on a same position on the wharve member (7a) of the spindle (7) only during the subsequent 4th doff It is also possible to pre¬define more than 3 different positions for depositing the under winding on the wharve member (7a) of the spindle (7). The PLC (15) is also disposed for the coordinated driving of the drafting rollers (2a), (2b) and (2c), the spindle (7) and the ring rail (4). The above drive member provides precisely controlled movement to the ring rail (4) which facilitates the formation of the under winding at the predetermined positions on the wharve member (7a) of the spindle (7). During subsequent doffing the position of the under winding is shifted below or above the previously formed under winding, as programmed, as illustrated in Fig 3. Once underwinding is formed, immediately the doffing cycle is initiated and an auto doffer attached to the ring spinning and twisting machine doffs the cop and places them on an intermediate peg. During the doffing the yam present between the final winding and the under winding is cut off by the crown (11) and cutter (12). Then the new and empty conical tubes arranged underneath the spindle rail which are re-fitted on the spindle (7). Subsequently the ring rail (4) with the leading end of the under winding guided by the ring traveler is moved upwards to a predetermined position by the ring rail drive system for the commencement of the cop built up on the fresh empty conical tube loaded on the spindle by the auto doffer. Then the spindle is restarted and the yam leading from the under winding being connected to the first few windings around the empty conical tube and the cop built up being continued. During the subsequent doffing the end connecting the under winding layer and the initial winding being guided by the said crown (11) and cut off by the cutter (12). Now both the ends of the previously formed under winding is free and being thrown off from the wharve member (7a) by the centrifugal force generated by the rotation of the spindle. It is to be noted that since this invention employs means for laying the under winding at different pre determined location either below or above the previously formed under winding as explained it is also possible that the layers of under winding may thrown out from the wharve member (7a) of the spindle (7) due to the centrifugal force of the spindle. Under circumstances where the underwinding if formed overlapping the previously formed one, the under winding layers may not be cut off by the crown (11) and the cutter (12) during subsequent doffing, instead the same will go along with the cop in the form of tail at the bottom portion of the cop. Figs 4 & 5 provide a schematic diagram for the working of the present invention. Fig 4 provides a schematic diagram for the working of the system for non-overlapping underwinding in a textile ring spinning and twisting machine using a Programmable Logic Control. Fig 5 provides a schematic flow diagram for the working of the Programmable Logic Control used in Fig 4. Since this invention ensures no over lapping of the under winding, proper cutting of the trailing end of the under winding is effected by the crown (11) and cutter (12). This ensures trouble free doffing of the cops, since the position of the cops are not disturbed by the hanging end of the yam produced by improper cutting. Due to the fact the invention ensures that there is no over lapping of under winding, the cutter (12) will not experience any problem during the doffing cycle to cut the yam and the requirement of any expensive under winding cleaning arrangement is eliminated. This also results in that there is no unnecessary accumulation of the yam in the wharve member of the spindle and the possibilities of loss of power could be eliminated. Also with this arrangement it is enough to use the conventional crown and cutter rather than using costly spindle assembly with yam catching mechanism. Advantages 1. The underwinding system of the present invention results in lesser power consumption due to the elimination of unnecessary accumulation of yam about the wharve member. 2. The underwinding system of the present invention uses the spindle assembly, which is cheaper as compared with that of spindles with yam catching arrangement. 3. In the underwinding system of the present invention there is no overlapping of underwinding, this ensures proper cutting of the trailing end of the underwinding by the crown and cutter 4. The underwinding system of the present invention there is no need of employing a separate crown cleaning arrangement which is expensive, this reduces the cost of the equipment. 5. The underwinding system of the present invention ensures a trouble free doffing of the cops, since the position of the cops are not disturbed by the hanging end of the yam produced by improper cutting. 6. The underwinding system of the present invention does not require a separate underwinding cleaning arrangement since the under windings are not overlapping one another and the same will be cleaned by the centrifugal force generated by the rotation of the spindle. We Claim: 1. A system for underwinding of yam in a textile ring spinning and twisting machine subsequent to cop built up on a conical tube of a spindle, said system comprising: a plurality of spindle assemblies (9) with wharve members (7a) mounted on a ring rail assembly (4), said ring rail assemblies (4) operably connected to a drive member, wherein said drive member controlled by a control means (13a, 14,15 & 16), said control means (13a, 14, 15 & 16) disposed to perform an upward and downward motion, characterized in that said control means (13a, 14, 15 & 16) disposed to position said ring rail assembly (4) at pre-determined locations of said wharve member (7a) by regulating said drive member and to perform a non-overlapping underwinding of the yam on said wharve member (7a). 2. The system as claimed in claim 1, wherein said control means comprising a feedback arrangement (13a), a motor drive unit (14), Programmable Logic Controller (PLC) (15) and an input device (16). 3. The system as claimed in claim 2, wherein said input device (16) is a digital input device disposed to input the pre-determined positions of the underwinding of the yarn on said wharve member (7a). 4. The system as claimed in claim 2, wherein said Programmable Logic Controller (PLC) (15) disposed to control and direct the drive member of the ring rail assembly (4) for executing the non-overlapping underwinding of the yarn on said wharve member (7a), at pre-determined positions. 5. The system as claimed in claim 4, wherein said Programmable Logic Controller (PLC) (15) disposed to iterate the sequence of pre-determined positions of the underwinding. 6. The system as claimed in claim 2, wherein said feedback arrangement (13a) is a rotary encoder disposed to monitor the position of the ring rail assembly (4) at pre¬determined positions on said wharve member (7a). 7. The system as claimed in claim 2, wherein said motor drive unit (14) disposed to regulate the speed of the motor (13) for underwinding on said wharve member (7a). 8. The system as claimed in claim 1, wherein the pre-determined positions of underwinding of the yarn on said wharve member (7a) are either below or above the previously formed under winding. 9. The system as claimed in claim 8, wherein the number of pre-determined positions for under winding of yam on said wharve member (7a) is more than 2, preferably three positions.

Documents:

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305-che-2004 abstract.pdf

305-che-2004 claims.pdf

305-che-2004 correspondence-others.pdf

305-che-2004 correspondence-po.pdf

305-che-2004 description(complete).pdf

305-che-2004 drawings.pdf

305-che-2004 form-1.pdf

305-che-2004 form-13.pdf

305-che-2004 form-19.pdf

305-che-2004 form-26.pdf

305-che-2004 form-3.pdf

305-che-2004 form-5.pdf