CN112867816A

CN112867816A - Bobbin drive unit, yarn feeding device and holder for holding bobbin

Info

Publication number: CN112867816A
Application number: CN201980068766.4A
Authority: CN
Inventors: P·约瑟夫松; B·约翰松; T·彼得森
Original assignee: Van Der Waals Sweden
Current assignee: Van Der Waals Sweden
Priority date: 2018-10-18
Filing date: 2019-10-14
Publication date: 2021-05-28
Also published as: EP3867432A1; WO2020080997A1

Abstract

Described is in particular a spool drive unit (13) comprising a spool motor (14) configured to rotate a spool (50) about an axis of a spool tube (52). The spool drive unit includes a first accessory (53) having a support configured to hold a first end of the spool tube and a second accessory (54) having a support configured to hold a second end of the spool tube. The spool can then be rotated when mounted in both ends of the tube. Accordingly, a spool drive unit is provided which is configured to retain a spool in both tube ends of the spool. By fixing both end portions of the bobbin tube, the bobbin can be rotated at high speed without generating vibration or oscillation to the bobbin driver or surrounding parts, which would otherwise possibly interfere with the sensor or damage the parts, and possibly shorten the service life of the parts of the yarn feeding device.

Description

Bobbin drive unit, yarn feeding device and holder for holding bobbin

Technical Field

The present disclosure relates to a spool drive unit and an apparatus associated with the spool drive unit.

Background

The general trend in weaving is the increasing speed of the weaving machines. Another trend is to increase the use of flat or tape-shaped yarns, which should be inserted without any twisting. Examples of such yarns are polypropylene tapes, carbon fibre tapes, aramid and glass fibre tapes. Currently, the speed at which rapier looms weave flat or ribbon yarns without twist is limited by the low capacity of the zero twist yarn feeding devices that exist today.

Existing systems for feeding yarn without torsion (zero torsion) usually have an unwinding motor controlled by measuring the length of a large coil buffer located between the bobbin and the loom. The coil may be freely suspended or have mechanical members forming the coil by gravity, pressurized air or by negative pressure (aspirator). The existing systems can be considered as storage feeders, in which the loom can take out the amount of yarn it needs, so-called "passive yarn feeding" or "feed on demand".

W02018013033 describes a yarn feeding device configured to weave textile articles at high speed with zero twist using a rapier loom. The weft feeding device is adapted to control the weft yarn by simultaneously controlling the speed of the motor-driven bobbin and the speed of the motor-driven coil buffer apparatus. During each cycle of the weaving machine, the motor-driven spools are driven to supply the correct amount of weft yarn.

There is a continuing desire to improve yarn feed to textile machines. Therefore, there is a need for an improved yarn feeding apparatus.

Disclosure of Invention

It is an object of the present invention to provide an improved yarn feeder device.

This and/or other objects are achieved by a weft feeding device as set forth in the appended claims.

As already appreciated, the high development of the weaving industry today and in the future will place high demands on the components in order for the yarn feeding device to function properly.

This problem is solved by providing a spool drive unit comprising a spool motor configured to rotate an axis of a spool bobbin tube to unwind yarn from the spool. The spool drive unit includes a first accessory having a support configured to hold a first end of the spool tube and a second accessory having a support configured to hold a second end of the spool tube. The spool can then be rotated when mounted in both ends of the tube. Accordingly, a spool drive unit is provided which is configured to secure a spool in both tube ends of the spool. By fixing both end portions of the bobbin tube, the bobbin can be rotated at high speed without generating vibration or oscillation to the bobbin driver or surrounding parts, which would otherwise possibly interfere with the sensor or damage the parts, and possibly shorten the service life of the parts of the yarn feeding device. This may be particularly advantageous when the bobbin drive unit is configured to unwind the yarn tangentially from the bobbin with a so-called zero twist feed.

According to one embodiment, at least one of said first and second accessories is provided with a quick-release mechanism, i.e. a mechanism that allows quick and easy disassembly of the accessory. The quick release mechanism may be any type of known quick release mechanism that is capable of releasing an accessory in a single action without, for example, loosening a nut or bolt or performing a similar action that requires multiple actions and is time consuming and may require the use of a tool. Thus, when rotating in the spool drive unit, the spool can be replaced quickly and easily while being fixed in both end portions without the use of tools.

According to one embodiment, a shaft is provided that is connectable to an interior of a bobbin tube. Thus, it is possible to provide a holder for attaching both sides of the tube of the spool to the spool drive unit, which is easy to replace.

According to one embodiment, the shaft is connected in one end to the motor and in a second end to a support for holding the shaft. Thus, a mechanism is obtained by which the shaft can be rotated by one single motor.

According to one embodiment, the shaft is connected to the motor in both ends. Thus, a mechanism is obtained wherein the shaft can be rotated by two motors, such that an increased force can be applied to rotate the spool without using a larger motor, and wherein the need for traction does not increase, since both ends of the tube can be used to obtain traction.

According to one embodiment, a spool holder for rotatably holding one or both ends of a spool tube is provided, wherein the spool holder is connected to a motor of a spool drive. Thus, an alternative mechanism for attaching the spool to the spool drive unit is obtained, wherein the spool does not need to be connected to the shaft.

According to one embodiment, the bobbin holder comprises at least a first tapered element and preferably also a second tapered element, the first and second tapered elements being arranged to be attached to the first and second end of the tube, respectively. Thus, an effective means for holding the spool in place is provided. The tapered element may absorb some of the deviation between the inner diameters of different tubes on different spools.

According to one embodiment, the bobbin holder is formed by a cylindrical element configured to be axially inserted into the tube to center the bobbin. The retainer may also include elements that press axially against the sides of the spool to transmit force from the motor and rotate the spool.

According to one embodiment, a support is provided at each side of the spool to prevent the spool from falling off when released from the accessory.

According to a second aspect of the present invention, a yarn feeding device is provided, comprising a yarn buffering device connected to a spool drive unit according to the above. Thereby, the entire yarn feeding device may benefit from reduced vibrations caused by keeping the spool, in particular the bobbin tube, at both ends while rotating the spool by the spool drive unit.

According to a third aspect of the present invention there is provided a holder for holding a spool, the holder comprising a shaft comprising an expandable portion configured to lock to the interior of a tube of the spool. Accordingly, an efficient holder for holding a spool fixed on both sides of the spool while being rotated by a spool driving unit is provided.

According to one embodiment, the expandable portion includes a locking element configured to press against an interior of the tube of the spool. Thus, a mechanism is provided in which the expandable portion can be locked to the tube by high friction.

According to one embodiment, the expandable portion includes a locking element configured to penetrate into an interior of the tube of the spool. Thus, a mechanism is provided in which the expandable portion can be effectively locked to the tube.

According to one embodiment, the locking element is provided with a recess. Thus, when outside the tube, the locking element may be held in place, for example by an O-ring placed in a recess.

Drawings

The invention will now be described in more detail, by way of non-limiting example, with reference to the accompanying drawings, in which:

figure 1 is a view showing a weft feeding device,

figures 2 and 3 show a spool drive unit according to a first embodiment,

figures 4 and 5 show a holder for a spool,

figures 6 and 7 show the holder when placed in the support for rotating the spool,

figures 8 and 9 show a spool drive unit according to a second embodiment.

Detailed Description

Hereinafter, a weft feeding device, in particular a bobbin drive unit that can be used in such a weft feeding device, will be described. In the drawings, like reference characters designate like or corresponding elements throughout the several views. It will be appreciated that these figures are for illustration only and do not limit the scope of the invention in any way. Moreover, features from different described embodiments may be combined to meet specific implementation requirements.

In fig. 1, an exemplary weft feeding device 12 comprising a motor driven bobbin 13 is shown. The unit for rotating the spool when no spool is placed in the drive unit is herein also referred to as spool drive unit 13. The exemplary yarn feeding apparatus of fig. 1 includes a motor-driven stitch cushioning device 16. The device 12 can be used to feed the yarn with zero twist. In the device 12, the weft yarn 40 is unwound tangentially from the motor-driven bobbin 13. The motor-driven spool is connected to a motor 14.

According to some embodiments, the motor 14 may be directly connected to the shaft on which the spool is located. According to some embodiments, the motor is connected via a gear transmission, or the spool is rotated by the motor 14 through a linear shaft. Other configurations for rotating the spool by controlling the motor 14 are contemplated. The weft yarn passes through a motor-driven stitch buffer device 16, which is adapted to form a weft buffer. Weft yarn is supplied to the loom 10 from a motor-driven buffer device 16. The weaving machine 10 can be, for example, a rapier weaving machine or a projectile weaving machine. The motorized buffer device 16 may be formed from a yarn loop forming arm 22. The arm 22 can be moved to form an adjustable buffer for the weft thread to be supplied to the weaving machine 10. Movement of the arm 22 is effected by a motor 18 connected to the arm 22. The arm may be coupled directly to the motor shaft or via a gear arrangement. A force sensor or tension sensor 29 may also be provided to detect and output a signal indicative of the actual yarn tension. In the arrangement according to fig. 1, the weft thread inserted into the weaving machine will always have a controlled thread tension, i.e. no loose thread is pulled into the weaving machine. The arm motor 18, as well as the motor 14 of the motor-driven spool 13, may be controlled by a controller 32, as will be described in more detail below.

According to one embodiment, the motor driven spool 13 is configured to be deployed by a central drive, as shown in fig. 1.

When the weft feeding device 12 is controlled as described above, the controller 32 can be used. The controller may be provided with control data to control the speed at which the motor 14 drives the bobbin and the movement of the motor-driven coil buffer device 16. By controlling the motor-driven bobbin 13 and the motor-driven stitch cushioning device 16, weft yarn can be correctly supplied to the loom at a high weaving speed.

When some types of yarn feeding devices are used, such as the above-mentioned yarn feeding devices for providing zero twist feed of the yarn, it is not possible to connect the tail to a new spool.

As a result, for each spool change, the loom is stopped and remains stopped until the spool is changed and the machine can be restarted.

For reasons of high productivity it would be advantageous if the bobbin change could be made quickly to minimize downtime of the loom.

In conventional yarn feeding devices, the spool is rotated by a motor, or by the yarn drawn by the loom, which is generally fixed to a shaft projecting from the motor. The shaft has a free end and the tube of the spool can enter over the free end of the shaft.

However, in high speed applications that can be achieved using the yarn feeding device shown in fig. 1, it has been found that fixing the spool to the shaft, as in conventional systems, creates problems. One problem has been found to be caused by a configuration in which the shaft rotates the spool in one end and has a free end. Rotation of one end can cause vibrations in the system when the other end is free. These vibrations or oscillations or similar phenomena can severely disturb the sensor signals used by the control system. When the sensor signal is disturbed, the sensor signal may become unreliable and often impair the performance of the control system. Another disadvantage caused by such vibrations and oscillations is that they propagate to the rest of the yarn feeding device and potentially disturb other fields and shorten the life of the components in the system.

Therefore, when increasing the speed of a yarn feeding device such as that shown in fig. 1, increased stability is often required, and there is also a need to increase the need to transfer high torque from the motor to the spool at acceleration.

This can be achieved by attaching the tube of the spool in both ends. Furthermore, when the spool is attached in both ends, a quick-release mechanism may be provided on the accessory for fixing the spool in order to facilitate the replacement of the spool. The accessories used are preferably designed to allow spools with different lengths of tubing and also to allow different internal diameters of the tubing.

According to one embodiment, a first end of the spool is connected to a motor driving the spool and a further second end is connected to a shaft portion rotatably mounted by a support. The second end can advantageously be moved in the axial direction or mainly in the axial direction by means of a quick-release mechanism.

In fig. 2, a yarn feeding device comprising a spool drive unit 13 is shown. The spool drive unit 13 includes a motor 14. The motor 14 is configured to rotate the spool 50. The spool 50 has a spool body with a tube 52. In use, actuation of the motor 14 will cause the spool 50 to rotate about the axis of the tube 52, thereby unwinding weft yarn from the spool 50. The support frame 51 is provided to support all the parts of the bobbin driving unit 13. According to one embodiment, the spool drive unit 13 comprises a first appendix 53 and a second appendix 54, the first appendix 53 having a support configured to hold a first end of the tube 52, the second appendix 54 having a support configured to hold a second end of the tube, so that the spool 50 can be rotated to feed the yarn to the loom when attached to both ends of the spool drive unit. Thus, the supporting members are provided at both sides of the end of the bobbin. The support may be part of the motor or a separate support may be provided. Thereby, the spool 50 can be rotated while being fixed at both end portions of the spool tube. In other words, in operation, there is no free end of the bobbin that would cause vibration.

In some embodiments, the

accessories

53, 54 may comprise

bobbin holders

56, 57 for rotatably holding the two ends of the tube, at least one of the bobbin holders being connected to the motor 14 of the bobbin drive unit 13. The

retainers

56, 57 may be formed by tapered elements that are connected to the tube 52 by the clamping force that locks the

accessories

56, 57 to the tube when the tapered elements are brought closer to each other. The conical element will have dimensions that are adapted to the inner diameter of the tube 52. In order to be able to transmit high torques, in particular during acceleration and deceleration of the spool, the conical element on the side of the motor 14 may have a high friction surface providing a friction higher than a certain set threshold. In one embodiment, the conical portion may also be provided with a sharp edge, such as a knife-shaped portion, which penetrates the surface of the bobbin tube in order to obtain a sufficiently strong connection to transmit the high torques, which are necessary for high accelerations or decelerations. Other solutions to obtain such transmission are also possible.

According to some embodiments, the holder in the other end may be formed by a similar conical element and fixed by means of a support to a device which is easy to open in the axial direction or mainly in the axial direction, see below. However, when the conical element is not suitable for transmitting torque from the motor, the conical element does not need to take any extra measures to obtain its high friction with the center of the bobbin. Since different spool types have different lengths and different inner diameters of the tube 52, the second accessory 54 advantageously has means to accommodate varying tube diameters and/or tube lengths, such as by a mechanism configured to move the accessory in an axial direction. Also, the tapered elements may be interchangeable, and the shape of the tapered elements themselves allows for some variation in the spool tube diameter. When switching from one spool type to another spool type, it is preferable to set to adjust the new spool tube length and/or the spool tube diameter. The holder may have other shapes than a conical element. For example a cylindrical portion that centers the tube and a high friction portion that connects to the tube. Other retainers are also contemplated.

According to some embodiments, one or both of the accessories are provided with a quick release mechanism 55. The quick release mechanism 55 may be of several types. In fig. 2, the quick release mechanism 55 is mechanical and is operated by turning a lever. According to some embodiments, the quick-release mechanism is a pneumatic type mechanism, i.e. a quick-release mechanism working with a pneumatic device. According to some embodiments, the quick-release mechanism is a hydraulic type mechanism, i.e. a quick-release mechanism working with a hydraulic device. In a quick release mechanism of this type, the quick release mechanism may be a pneumatic or hydraulic cylinder which opens the spool holder automatically at the command of the operator or by a command from the controller 32 (see fig. 1) when the end of the spool sensor has detected that the spool is almost running out and the yarn feeding device has stopped for spool switching.

Alternatively, the quick release mechanism 55 may comprise an electric motor that opens the spool holder in the same way as a hydraulic or pneumatic based quick release mechanism opens the cylinder. In another embodiment, the quick release mechanism may be a spring-based device that provides a spring force. The spring force may partially or completely change the force required to hold or release the quick release mechanism.

In fig. 3, the spool drive unit 13 is shown with the quick release mechanism 55 in an open state. In the open state, the spool 50 may be removed and a spool replacement may be performed.

In fig. 4, another type of retainer 66 for the bobbin tube 52 is shown. Retainer 66 includes a shaft 62 having an expandable portion 67, the expandable portion 67 accommodating the inner diameter of tube 52 in the central portion of the spool. In order to be able to transmit high torques, in particular during acceleration and deceleration of the spool, the expandable portion 67 may in some embodiments be equipped with a locking element 69 or the like, which locking element 69 or the like may be expanded towards the interior of the tube of the spool. According to one embodiment, the locking element may have a knife or other sharp portion to penetrate into the tube of the spool. The tube is typically made of paper or plastic.

The shaft 62 is designed to be easily removable from the side on which the motor is disposed and the other side, typically the support side. The shaft 62 may be locked to the interior of the spool using the expandable portion 67 or to the end using, for example, a cone or other element. In the weaving plant, there may be a plurality of such holders 66 with shafts 62 for each channel of the yarn feeding device, for example two holders may be used. One retainer 66 may then be mounted on the spool in use and the other retainer 66 may be mounted on another spool for subsequent use so that the spool can be quickly and easily replaced after the spool in use is exhausted. The holder 66 with the shaft 62 and its fixing means thus provides a design allowing easy and quick replacement of the spool.

In fig. 4, the retainer 66 is shown in the expandable portion retracted position. In fig. 5, the expandable portion is in a protruding position, and a locking element 69 protrudes from the expandable portion to attach to the inner surface of the bobbin tube to connect the spool 50 in a locked position. The locking element 69 may be provided with a recess 63. The recess 63 may be provided on a radially outer side of the locking element 69. The recess 63 may be configured to receive a resilient member, such as an O-ring, that may be provided to hold the locking member in place when the retainer 66 is located outside of the bobbin 52.

In fig. 6, the retainer 66 is shown placed and locked in the tube 52 of the spool 50. The locking element 69 is in contact with the interior of the tube 52.

Fig. 7 is similar to fig. 6, but in fig. 7, the locking element 69 is retracted and the retainer 66 is free to be removed from the tube 52. Thus, there will be a space 68 between the locking element 69 and the tube 52.

In fig. 8, the holder 66 is shown in the spool drive unit 13. The spool drive unit 13 is provided with a quick release mechanism 55. The quick release mechanism 55 is of the mechanical type but has another design than the quick release mechanism in figure 2 and is commonly referred to as a toggle clamp, in which a lever is pulled to release the mechanism. In fig. 8, the quick release mechanism 55 is in a closed position in which the retainer 66 is locked in the spool drive unit 13. Any other type of quick release mechanism may be used, such as a center lock mechanism. According to some embodiments, a release mechanism assembly may be used that does not require a separate tool to lock or release the spool.

Fig. 9 is similar to fig. 8. In fig. 9, the quick release mechanism 55 is in an open position in which the retainer 66 can be released from the spool drive unit 13. Fig. 9 also shows a support 70 for easier replacement of the spool 55. When replacing the spool 50, the quick release mechanism 55 is opened and the spool tube needs to be supported so as not to fall off. This can be addressed by manually holding the spool 50 during replacement. However, by providing supports 70 on the spool drive unit on each side of the spool, the spool 50 will remain in place even when the spool is released. The support 70 will typically drop the spool a few millimeters, e.g., 1mm to 10mm, which may be the distance from the outer diameter of the spool tube to the support. When a new full spool is placed, the spool may typically weigh up to 6kg, sometimes even up to 12 kg. As is readily understood, it may be difficult to hold and place the spool in the correct position with only one hand while locking the quick release mechanism with the other hand. With the support 70, the spool 50 can be placed in the access position with both hands and then the quick release mechanism can be closed. If the tapered entry feature is used as a retainer, the spool tube will be automatically centered. If other types of retainers are used, the operator may need to manually center the spool tube, but in this case, the operator may now center one end of the spool tube with one hand. The gap between the support and the outer diameter of the spool tube is preferably as short as possible, but still safe. This gap is safe in operation with the spool rotating, the support member does not touch the spool tube. Typically, the distance may be about 1mm to 10 mm.

Claims

1. A spool drive unit (13) configured to unwind yarn from a spool (50), the spool drive unit comprising a spool motor (14) configured to rotate the spool (50) about an axis of a spool tube (52), the spool drive unit comprising a first accessory (53) and a second accessory (54), the first accessory (53) having a support configured to be connected from a first end of the spool tube, the second accessory (54) having a support configured to be connected from a second end of the spool tube, such that the spool is rotatable in the supports at both side ends of the tube.

2. Spool drive unit according to claim 1 wherein at least one of the first and second accessories is provided with a quick release mechanism (55).

3. The spool drive unit according to claim 1 or 2 comprising a shaft (62) connectable to an interior of the spool tube.

4. The spool drive unit according to claim 3 wherein said shaft is connected in one end to a motor and in a second end rotatably connected to a support for holding said shaft.

5. The spool drive unit according to claim 3 wherein said shaft is connected to a motor in both ends.

6. The spool drive unit according to claim 1 or 2 comprising a spool holder (56, 57) for rotatably holding one or both ends of the spool tube, the spool holder being connected to a motor of the spool drive.

7. The spool drive unit according to claim 6 wherein said spool holder comprises at least one first tapered element arranged to be attached to at least one of said first and second ends of said tube.

8. The spool drive unit according to claim 6 wherein said spool holder comprises a cylindrical portion configured to be axially inserted into said tube.

9. The spool drive unit according to any one of claims 1 to 8 wherein said spool drive unit comprises a support (70) provided at each of said first and second accessories for preventing the spool from falling off when released from said first and second accessories.

10. The spool drive unit according to any one of claims 1 to 9 wherein said spool drive unit is configured to rotate said spool to tangentially unwind yarn from said spool.

11. A yarn feeding device (12) comprising a yarn buffering device (16) connected to a spool drive unit according to any of claims 1-10.

12. A retainer (66) for retaining a spool, the retainer comprising a shaft (62) including an expandable portion (67) configured to lock to an interior of a tube of the spool.

13. The holder of claim 12, wherein the expandable portion includes a locking element (69) configured to press against an interior of a tube of the spool.

14. The retainer of claim 12, wherein the expandable portion includes a locking element (69) configured to penetrate into an interior of a tube of the spool.

15. Holder according to claim 13 or 14, wherein the locking element (69) is provided with a recess (63).