CLIAMS:What is claimed is:
1. An auto-doffing system comprising:
a plurality of intermediates rails configured for collecting and placing a plurality of full bobbins and empty bobbins;
a plurality of pegs placed on each intermediate rail, configured for holding with the plurality of bobbins;
atleast two pneumatic cylinders configured for enabling a movement of the intermediate rails, wherein each cylinder is placed on either side of the intermediate rail;
a doffing bar configured for transferring the empty and full bobbins to the pegs on the intermediate rails; and
a plurality of sensors incorporated in cylinders are configured to monitor the movement of the intermediate rails.

2. The system according to claim 1, wherein a plurality of grippers are assembled on the doffing bar, wherein the plurality of grippers comprises a first component engaging with the empty bobbins and a second component engaging with the full bobbins.

3. The system according to claim 1, wherein the successive pegs on the intermediate rail are placed at an predetermined pitch distance, wherein the pitch distance between the successive pegs is equal throughout the intermediate rail.

4. The system according to claim 1, wherein the intermediate rails are configured to toggle between a first position and a second position by moving the intermediate rail by half the pitch distance.

5. The system according to claim 1, wherein the pitch distance between two successive pegs on the intermediate rails depend on length of a spindle gauge.

6. The system according to claim 1, wherein the plurality of empty bobbins and the plurality of full bobbins are placed on consecutive pegs, wherein the doffing bar is subjected to the plurality of empty bobbins when the intermediate rail is at the first position, and wherein the doffing bar is subjected to the plurality of full bobbins when the intermediate rail is at the second position.

7. The system according to claim 1, wherein the plurality of grippers on the doffing bar are configured to collect the plurality of empty bobbins from a caddy in a peg tray, wherein the empty bobbins are placed on to the pegs of the intermediate rail, when the intermediate rail is in the first position during a doffing cycle.

8. The system according to claim 1, wherein the pegs of the intermediate rail are aligned with respective a spindle axis of a spindle rail, when the intermediate rail is in the first position during a doffing cycle, wherein the doffing bar picks up the plurality of empty bobbins from the intermediate rail and places the empty bobbins onto a plurality of spindles of the spindle rail.

9. The system according to claim 1, wherein the plurality of grippers on the doffing bar are configured to pick the plurality of full bobbins from the plurality of spindles of the spindle rail, wherein the full bobbins are placed on to the pegs of the intermediate rail, when the intermediate rail is in the second position during the doffing cycle.

10. The system according to claim 1, wherein the doffing bar picks up the plurality of full bobbins from the intermediate rail, when the intermediate rail is in second position, wherein the doffer bar places the full bobbins onto the caddy in the peg tray.

11. A method for operating a plurality of intermediate rails in an auto doffing system comprising steps of:
picking a plurality of empty bobbins from a candy in a peg tray;
moving a plurality of intermediate rails from a second position to a first position;
placing the plurality of empty bobbins over a plurality of pegs in the first position of the intermediate rails;
picking a plurality of full bobbins from a spindle rail;
moving the intermediate rails from the first position to the second position;
placing the plurality of full bobbins on the plurality of pegs in the second position of the intermediate rails;
moving the intermediate rails from the second position to the first position of the intermediate rails;
picking the plurality of empty bobbins from the first position of the intermediate rails;
placing the plurality of collected empty bobbins onto a plurality of spindles of the spindle rail;
moving the intermediate rails from the first position to the second position;
picking the plurality of full bobbins from the second position of the intermediate rails; and
placing the plurality of collected full bobbins onto the caddy in the peg tray.

12. The method according to claim 12, wherein the plurality of full bobbins on the plurality of spindles of the spindle rail is replaced by the plurality of empty bobbins.

13. The method according to claim 12, wherein the successive pegs on the intermediate rails are separated by a predefined pitch distance for positioning the empty bobbins and the full bobbins in a consecutive manner.

14. The method according to claim 12, wherein the plurality of empty bobbins are placed when the intermediate rails are in the first position and the plurality of empty bobbins are placed when the intermediate rails are in the second position.

15. The method according to claim 12, wherein the doffing bar is subjected to the plurality of bobbins by moving the intermediate rail by half the pitch distance.

Dated this 09th Day of January 2015
Rakesh Prabhu,
Patent Agent,
ALMT Legal, Advocates & Solicitors,
2, Lavelle Road, Bangalore 560 001
To,
The Controller of Patents,
The Patent Office,
At Chennai
,TagSPECI:A) TECHNICAL FIELD
[0001] The present invention generally relates to a textile machine and particularly relates to an automated doffing system and method adopted in the textile machine. The present invention more particularly relates to a system providing a flexible intermediate rail in the auto doffer and a method for operating the intermediate rail so as to reduce a doffing time.

B) BACKGROUND OF THE INVENTION
[0002] In modern mills the doffing process is relatively automated with a mechanical doffer fitted to the winder that cuts and aspirates the yarn wound on bobbins, removes the filled bobbins and places them in a yarn peg tray. The doffer further fits the empty tubes and transfers the yarn so that the winding can be continued. Automatic doffing enables labor requirements and doffing times to be drastically reduced.
[0003] According to the existing methods, the automatic doffers have intermediate rails with a fixed position. The intermediate rails have pegs with a quantity equal to spindles. For forming yarn packages continuously, the bobbins filled with yarn need to be removed from spindles and the empty bobbins need to be inserted on the spindles to initiate the next package. A gripper mechanism is used to hold the bobbins during the process. As the same gripper is used for both the operations, the full bobbins picked from the spindles have to be unloaded on the pegs so as to free the grippers for holding the empty bobbins. The aforementioned process involves a movement of the doffing bars for a higher distance and hence the process requires a higher doffing time. Furthermore, some of the existing auto doffers do not comprise an intermediate position for placing the full bobbins. In such machines, the full bobbins are directly transported from the spindles to the conveyor belt. After the placement of full bobbins, the conveyor belt moves by certain distance so as to subject the empty bobbins to the doffing bars. The machine has to be stopped to carry out the doffing process because of which the production time is wasted during doffing cycle .
[0004] Hence, there is a need for an improved automated doffing method and system with a reduced doffing time. Further there is a need for a system providing a reduced movement of doffing bars while performing the doffing process. Also, there is a need for a method to reduce the time taken to transport the full bobbins to a bottom position of the doffing system. Further there is a need for a method which consumes less time to lift the empty bobbins from the bottom position of the doffer.

C) OBJECT OF THE INVENTION
[0005] The primary object of the present invention is to provide an automated doffer system providing a method for reducing a doffing time of the doffing process.
[0006] Another object of the present invention is to provide an improved doffer system which requires lesser movement of doffing bars for replacing the filled bobbins on a guide rail with the empty bobbins.
[0007] Yet another object of the present invention is to provide a method for reducing the time taken to transport the full bobbins to a bottom position of the doffing system.
[0008] Yet another object of the present invention is to provide a method which consumes less time to lift the empty bobbins from the bottom position of the doffer.
[0009] Yet another object of the present invention is to enable the automated doffer to working continuously, thereby avoiding the system to get into idle mode.
[0010] These and other objects and advantages of the present invention will become readily apparent from the following detailed description taken in conjunction with the accompanying drawings.

D) SUMMARY OF THE INVENTION
[0011] The various embodiments of the present invention provide an improved automated doffing system. The system comprises a plurality of intermediates rails configured for collecting and placing a plurality of full bobbins and empty bobbins, a plurality of pegs placed on each intermediate rail, configured for holding with the plurality of bobbins, atleast two pneumatic cylinders configured for enabling a movement of the intermediate rails by placing each cylinder is either side of the intermediate rail, a doffing bar configured for transferring the empty and full bobbins to the pegs on the intermediate rails; and a plurality of sensors incorporated in cylinders are configured to monitor the movement of the intermediate rails.
[0012] According to an embodiment of the present invention, a plurality of grippers are assembled on the doffing bar. The plurality of grippers comprises a first component engaging with the empty bobbins and a second component engaging with the full bobbins.
[0013] According to an embodiment of the present invention, the successive pegs on the intermediate rail are placed at a predetermined pitch distance. The pitch distance between the successive pegs is equal throughout the intermediate rail.
[0014] According to an embodiment of the present invention, the intermediate rails are configured to toggle between a first position and a second position by moving the intermediate rail by half the pitch distance.
[0015] According to an embodiment of the present invention, the pitch distance between two successive pegs on the intermediate rails depend on length of a spindle gauge.
[0016] According to an embodiment of the present invention, the plurality of empty bobbins and the plurality of full bobbins are placed on consecutive pegs. The doffing bar is subjected to the plurality of empty bobbins when the intermediate rail is at the first position. The doffing bar is subjected to the plurality of full bobbins when the intermediate rail is at the second position.
[0017] According to an embodiment of the present invention, the plurality of grippers on the doffing bar is configured to collect the plurality of empty bobbins from a caddy in a peg tray. The empty bobbins are placed on to the pegs of the intermediate rail, when the intermediate rail is in the first position during a doffing cycle.
[0018] According to an embodiment of the present invention, the pegs of the intermediate rail are aligned with respective a spindle axis of a spindle rail, when the intermediate rail is in the first position during a doffing cycle. The doffing bar picks up the plurality of empty bobbins from the intermediate rail and places the empty bobbins onto a plurality of spindles of the spindle rail.
[0019] According to an embodiment of the present invention, the plurality of grippers on the doffing bar is configured to pick the plurality of full bobbins from the plurality of spindles of the spindle rail. The full bobbins are placed on to the pegs of the intermediate rail, when the intermediate rail is in the second position during the doffing cycle.
[0020] According to an embodiment of the present invention, the doffing bar picks up the plurality of full bobbins from the intermediate rail, when the intermediate rail is in second position. The doffer bar places the full bobbins onto the caddy in the peg tray.
[0021] The various embodiments of the present invention provides a method for operating a plurality of intermediate rails in an auto doffing system. The method comprises steps of: picking the plurality of empty bobbins from the candy in the peg tray. The plurality of intermediate rails is moved from the second position to the first position. The plurality of empty bobbins is placed over the plurality of pegs in the first position of the intermediate rails. The plurality of full bobbins is picked from the spindle rail. The intermediate rails are moved from the first position to the second position. The plurality of full bobbins is placed on the plurality of pegs in the second position of the intermediate rails. The intermediate rails are moved from the second position to the first position of the intermediate rails. The plurality of empty bobbins is picked from the first position of the intermediate rails. The plurality of collected empty bobbins is placed onto the plurality of spindles of the spindle rail. The plurality of full bobbins is picked from the second position of the intermediate rails. The plurality of collected full bobbins is placed onto the caddy in the peg tray.
[0022] According to an embodiment of the present invention, wherein the plurality of full bobbins on the plurality of spindles of the spindle rail is replaced by the plurality of empty bobbins.
[0023] According to an embodiment of the present invention, the successive pegs on the intermediate rails are separated by a predefined pitch distance for positioning the empty bobbins and the full bobbins in a consecutive manner,
[0024] According to an embodiment of the present invention, the plurality of empty bobbins is placed when the intermediate rails are in the first position and the plurality of empty bobbins is placed when the intermediate rails are in the second position.
[0025] According to an embodiment of the present invention, the doffing bar is subjected to the plurality of bobbins by moving the intermediate rail by half the pitch distance.
[0026] These and other aspects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating the preferred embodiments and numerous specific details thereof, are given by way of an illustration and not of a limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.

E) BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The other objects, features and advantages will occur to those skilled in the art from the following description of the preferred embodiment and the accompanying drawings in which:
[0028] FIG. 1 illustrates a schematic diagram of an intermediate rail installed in an automated doffing system, according to one embodiment of the present invention.
[0029] FIG. 2A-2G illustrates various stages in a doffing cycle for replacing a plurality of full bobbins with a plurality of empty bobbins, according to one embodiment of the present invention.
[0030] FIG. 3A-3B illustrates a flowchart indicating the steps involved in a method for operating the intermediate rail in the auto doffing system, according to an embodiment of present invention.
[0031] Although the specific features of the present invention are shown in some drawings and not in others. This is done for convenience only as each feature may be combined with any or all of the other features in accordance with the present invention.

F) DETAILED DESCRIPTION OF THE INVENTION
[0032] In the following detailed description, a reference is made to the accompanying drawings that form a part hereof, and in which the specific embodiments that may be practiced is shown by way of illustration. These embodiments are described in sufficient detail to enable those skilled in the art to practice the embodiments and it is to be understood that the logical, mechanical and other changes may be made without departing from the scope of the embodiments. The following detailed description is therefore not to be taken in a limiting sense.
[0033] The various embodiments of the present invention provide an improved automated doffing system with reduced doffing cycle time. The automated doffer is integrated in a textile ring spinning machine.
[0034] FIG. 1 illustrates a schematic diagram of an intermediate rail installed in an automated doffing system, according to one embodiment of the present invention. The auto doffer adopts a plurality of intermediate rails 101 for replacing a plurality of full bobbins on a plurality of spindles with a plurality of empty bobbins. The doffing system comprises atleast two intermediate rails per textile machine, where one of the intermediate rails is positioned on a right hand side of the machine and the other intermediate rail is positioned on a left hand side of the machine. A spindle rail incorporated in the machine carries a predetermined number of spindles arranged at a predetermined pitch. The intermediate rails are positioned near to the spindle rail. The intermediate rail 101 comprises a plurality of pegs 102 for holding the bobbins. The pegs 102 are aligned with the spindles on the spindle rail either for unloading the full bobbins from the spindles onto the intermediate rails 101or for loading the empty bobbins from the intermediate rails 101 to the spindles. The empty bobbins on the intermediate rail 101 are presented to the spindles on the spindle rail, whereas the full bobbins are dropped into a peg tray for further processing. The replacement process is automated by employing a doffing bar, which is configured to transfer the empty bobbins and full bobbins to the pegs 102 on the intermediate rails 101. A plurality of grippers is assembled on the doffing bar. The plurality of grippers comprises a holding element A for engaging with the empty bobbins and a holding element B for grasping the full bobbins from the spindle rail. The intermediate rails 101 are configured to move between position A and position B. The empty bobbins are placed on the intermediate rail 101, when the rail is in position A whereas the full bobbins are placed when the intermediate rail 101 is in position B. This arrangement enables the plurality of empty bobbins and the plurality of full bobbins to be placed on consecutive pegs. For example, if the empty bobbins are placed on odd numbered pegs then the full bobbins are placed on even numbered pegs. The movement of the rail 101 is linear or radial to change the position of intermediate rail 101 during a doffing cycle. The movement of the intermediate rails is controlled by atleast two pneumatic cylinders 103 and 104. One of the cylinders 103 is placed at a head stock of the doffing system, whereas the other cylinder 104 is placed on an end stock of the doffing system so as to enable the swinging movement of the intermediate rail between position A and position B. The pneumatic cylinders 103 and 104 are actuated by a plurality of sensors. The sensors are configured to control the position of the intermediate rails depending on the movement of the doffing bar and loading/unloading of the bobbins. The intermediate rail 101 is configured to hold both full bobbins and empty bobbins on the same platform. This arrangement reduces the movement of the doffing bar for collecting and placing the bobbins to their respective position thereby reducing the doffing time.
[0035] The successive pegs on the intermediate rail are placed at a predetermined pitch distance 105. The pitch distance 105 between the successive pegs is equal throughout the intermediate rail. The intermediate rails are configured to toggle between the position A and the position B by moving the intermediate rail by half the pitch distance 105. The positioning of the pegs for receiving the full bobbins or the positioning of the empty bobbins under the grippers is achieved by moving the intermediate rails by half the pitch distance 105. The pitch distance 105 between two successive pegs on the intermediate rails depend on length of a spindle gauge. For example, the pegs are fixed at 35 mm pitch distance for a spindle gauge of 70 mm or at 37.5 mm pitch distance for a spindle gauge of 75 mm. The doffing bar is subjected to the plurality of empty bobbins, when the intermediate rail is at the position A. The doffing bar is subjected to the plurality of full bobbins when the intermediate rail is at the position B. During the doffing cycle, the pegs of the intermediate rail are aligned with respective a spindle axis of the spindle rail when the intermediate rail is in the position A. The plurality of empty bobbins is arranged along the row of spindles so that each empty bobbin is positioned in front of the respective spindle. On alignment, the doffing bar replaces the full bobbins on the spindle with the empty bobbins from the intermediate rail.
[0036] FIG. 2A-2G illustrates various stages in a doffing cycle for replacing a plurality of full bobbins with a plurality of empty bobbins, according to one embodiment of the present invention. The doffing mechanism is initiated when the yarn package is full and the full bobbins 201 are ready for doffing. FIG. 2A shows first stage of the doffing mechanism. The full bobbins are available on the plurality of spindle 202 of the spindle rail. The empty bobbins 203 are readily loaded onto the pegs 204 of the intermediate rail, when the rail is in position A (as shown in FIG. 2A). According to FIG. 2B, the intermediate rail is moved from position A to position B for receiving the full bobbins 201 from the spindle rail. As shown in FIG 2C, the full bobbins 201 are picked up from the spindles 202 and placed on the pegs 204 at position B. In this stage, the intermediate rail has both full bobbins 201 and empty bobbins 203. In next stage, the intermediate rail is moved from position B to position A so as to align the empty bobbins 203 to the spindle axis (FIG. 2D). With respect to FIG.2E, in the following stage, the full bobbins 201 remain on the intermediate rail whereas the empty bobbins 203 are picked from the intermediate rail and placed on the spindles 202 of the spindle rail. To unload the full bobbins 201, the intermediate rail is moved from position A to position B, as shown in FIG. 2F. In final stage of the doffing mechanism, the full bobbins 201 are picked from the intermediate rail and placed on the pegs 205 of the peg tray 206.
[0037] FIG. 3A-3B illustrates a flowchart indicating the steps involved in a method for operating the intermediate rail in the auto doffing system, according to an embodiment of present invention. The empty bobbins are the tubes on which yarn is to wound. The empty bobbins replace the full bobbins on the spindle rail. A peg tray is fastened to a conveyor belt which carries the empty bobbins. The doffing cycle starts with the doffing bar loading the empty bobbins from the caddy of the peg tray (301). When all the empty bobbins are loaded, the plurality of sensors is activated to actuate the pneumatic cylinder. The pneumatic cylinder in-turn pushes the intermediate rail to position A (302). The doffing bar places the empty bobbins on to the pegs of the intermediate rail, when the rail is at position A (303). After emptying the bobbins, the doffing bar travels up to unload the full bobbins from the spindles of the spindle rail (304). The sensors are again activated when all full bobbins are unloaded. The sensors actuate the pneumatic cylinder to shift the intermediate rail to position B (305). The doffing bar arranges the full bobbins onto the pegs of the intermediate rail, when the rail is at position B (206). Further after arranging the bobbins, the intermediate rail is returned from the position B to the position A (307). The doffing bars picks the empty bobbins placed on the intermediate rail (308) and travels up to place the empty bobbins onto the spindles of the spindle rail (309). The intermediate rail is again shifted from position A to position B (310). As the rail returns to position B, the full bobbins on the intermediate rail are picked up by the doffing bar (311) and the unloaded bobbins are placed on the caddy of the peg tray on the conveyor belt (312). The yam produced by the spinning machine is wound on the empty spindles mounted on the plurality of rotating spindles.
[0038] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modifications.
[0039] Although the embodiments herein are described with various specific embodiments, it will be obvious for a person skilled in the art to practice the embodiments herein with modifications.

G) TECHNICAL ADVANTAGES OF THE INVENTION
[0040] The present invention facilitates an improved automated doffing system with a plurality of intermediate rails. The present invention further provides a method for replacing the full bobbins on the spindles with the empty bobbins. The method is configured to consume a lesser doffing time compared to the existing system. The doffing time of the doffing system is reduced as the movement of the doffing bar is reduced and the time taken to complete the doffing cycle is reduced. The life span of the doffing system is increased as the doffing mechanism move for lesser distance thereby reducing the wear and tear of the doffing system. The present invention has improved working accuracy as the stroke of conveyor belt is fixed and the structure is sturdy. Since the doffing time is reduced, the saved time is used for production thus increasing the yarn productivity.