JP7598463B2 - Weft yarn feeding device with clamping disc - Google Patents

Description

The present invention relates to a weft supplying device that provides multiple wefts in a loom and selectively supplies the wefts to a rapier for weft insertion, and to a loom equipped with a weft supplying device.

In a loom, particularly a rapier loom, the weft thread is inserted into the shed by the rapier from the insertion side of the loom. Usually, several weft threads are held together and inserted alternately according to the respective weaving pattern.

From WO 2020/052822, a weaving machine with a weft color selection device is known, which allows a number of weft threads to be fed to the rapier in a selected sequence. For this purpose, the weft color selection device has a thread guide, which has a thread guide hole on its outer circumferential surface. The weft thread to be fed is fed to the gripper by means of a feed needle.

In this case, the weft thread is held, for example, in a catch selvedge. However, this has the disadvantage that it must be removed in the finished textile and is therefore a waste part. This increases the material usage required for the production of the woven fabric.

Furthermore, from EP 3 425 094 A1, a weft manipulation device for a gripper weaving machine is known. Each provided weft thread is guided by a closed hole in a selection arm, which feeds the weft thread into the gripper. A clamp gripper for each weft thread is mounted on a support, which can be swiveled about a rotation axis. The weft threads converge from each selection arm towards a convergence point, after which the weft threads again fan out into the corresponding clamps on the support. In this case, the rotation axis of the support runs through the convergence point of the weft threads.

In response to this, the objective of the present invention is to provide a weft supplying device that reduces the deflection of the weft and reduces yarn waste during supply.

This problem is solved by the weft thread supplying device according to the invention as described in the independent claims and by a weaving machine equipped with such a weft thread supplying device. Preferred embodiments of the invention are evident from the respective dependent claims.

According to the invention, a weft feeder for providing a weaving machine with a number of weft threads and selectively feeding the active weft thread to the rapier comprises a rotatably drivable color selection disk arranged on its outer circumferential surface with a number of holes for receiving at least one weft thread in each case. The weft feeder according to the invention further comprises a rotatably drivable clamping disk arranged on its outer circumferential surface with a number of clamps for holding at least one weft thread in each case in a closed position. Between the color selection disk and the clamping disk, a feed needle is arranged, and the at least one active weft thread to be fed can be transferred from the feed position to the rapier via the feed needle in a transfer position. The feed position is a position where at least one active weft thread can be reached by rotating the color selection disk and one active clamp together with the clamping disk into a feed rotation position. Furthermore, the active clamp can be brought to an open position in which the clamp is located after the transfer of the weft thread to the rapier in order to release the active weft thread.

Usually, each hole accommodates only one weft thread. However, depending on the weaving pattern, it is possible for two or more weft threads to be fed through one hole by the feed needle to the rapier and introduced from the rapier during weft insertion. However, this is only possible if the position of the individual weft threads does not have to be twist-free in the fabric during weft insertion. In such a case, each hole of the color selection disk can accommodate more than one weft thread. However, for the sake of clarity, the invention is described below only with respect to one weft thread per hole, although this arrangement also applies in the case of several weft threads per hole, i.e. weft thread groups. With such a weft guide, a double weft thread can be introduced in a simple manner.

However, if it is desired that two weft threads are inserted in one double weft insertion without twisting, the two weft threads must preferably be guided in separate holes. In such a case, the feed needle has twice the receiving hole, i.e. a double recess for receiving the two weft threads separately. As a result, only one weft thread is introduced from each of the two holes to the rapier by only one feed needle in one stroke. A rapier for introducing two weft threads in one double weft insertion without twisting is described, for example, in DE 10 2018 222 722 C1. Both active weft threads for the double weft insertion are held in only one active clamp of the clamping disc and are clamped again in the same active clamp after the weft insertion. The clamping disc therefore usually has only half as many clamps as the color selection disc has holes. Usually, two weft threads each from adjacent holes, i.e. two adjacent weft threads, are grouped and held in one clamp. As a result, the combination of weft yarns inserted in one double weft insertion is determined by the yarn guide.

In one embodiment, the color selection disk is formed as a multi-part color selection disk with several partial disks, in particular with two partial disks. Both partial disks can be rotated independently of one another about a common axis of rotation. For this purpose, each partial disk usually has its own drive. The partial disks can be arranged axially one behind the other or can be located in the same plane. For example, the partial disks are arranged axially one behind the other, preferably with two partial disks having different partial circle diameters on which the holes are arranged. Thus, for example, the rear first partial disk has a larger partial circle diameter than the front second partial disk. In order to guide the weft thread held in the hole of the second partial disk through, the first partial disk has, for example, a curved groove on the partial circle diameter of the hole of the second disk and has a groove extending radially outward from this groove for the exit of the usable weft thread. If both partial disks are arranged in a plane, in particular the holes of both partial disks can be swiveled in a common swiveling plane. Insofar as the partial discs can be pivoted about a common pivot axis, the two partial discs can have crank-shaped bends, so that the bearings of the two partial discs are arranged axially offset from one another, but the holes nevertheless lie in a common pivot plane. Color selection discs with several partial discs are described, for example, in the above-cited International Publication WO 2020/052822.

The holes of the color selection disk are preferably formed as open holes. In this connection, open holes can in particular be understood as holes through which the weft thread can be removed radially outward, i.e. the open holes are formed in particular as radial notches on the outer circumferential surface of the color selection disk. Preferably, only at least one weft thread to be fed, which can be called the active weft thread, can be removed from the corresponding hole in the outward rotation position. The remaining weft threads are fixed in position in the respective open hole. The open holes of the active weft threads, which are located in the outward rotation position, are also called active holes. All holes except the active hole can be mechanically closed, for example by latches in the form of sliding guide disks. These holes are preferably arranged on one and the same predefined partial circle diameter around the rotation point of the color selection disk and open radially outward. The sliding guide disk has a circumferential cutout on the partial circle diameter around the rotation point of the color selection disk. Only in the region of the feed rotation position, the sliding guide disk has a radially outward recess that reaches the outer edge of the sliding guide disk and releases the active weft thread. In an alternative configuration, for example, each open hole has its own closure body, which closes the respective hole in the normal state, and only the active hole opens when rotating to the feed rotation position. In addition to the open holes, the holes can also be formed as closed holes. In the closed holes, the active weft thread is guided by and held in the hole during feeding to the rapier and also during weft insertion.

The clamping disc usually has a number of clamps corresponding to the total number of holes of the color selection disc or partial disc, or half the total number of holes in the case of double weft insertion without twist. Each weft thread to be fed thus runs from the yarn storage or storage bobbin through a hole in the color selection disc to the corresponding clamp on the clamping disc. Between the color selection disc and the clamping disc, the weft thread runs along a direct path, without any particular deflection. The clamp in which the active weft thread to be fed is located is also called the active clamp, as is the active hole in which the same active weft thread is located. To select the active weft thread to be fed from the provided weft threads, the color selection disc and the clamping disc are rotated into a rotation position in which the active clamp and the active hole are located in the feed rotation position and thus the active thread is located in the feed position. This rotation position of the clamping disc and the color selection disc is different for each clamp or hole feed rotation position. This is because the weft thread held by the corresponding clamp and hole must always be brought to the same presentation position in order to be received by the presentation needle. The presentation position is determined by the reception position of the presentation needle and is the same for each of the multiple weft threads provided in the case of a presentation needle with only one recess. In a double fork with two recesses, there is one presentation position each for the first active weft thread and the second active weft thread.

After rotating the color selection disk and the clamping disk to a rotational position in which at least one active weft thread to be fed is located in the feed position, the feed needle receives at least one active weft thread between the color selection disk and the clamping disk and brings at least one active weft thread to its transfer position. From this transfer position, the rapier receives the active weft thread. For this purpose, a recess or a double recess is preferably formed on the front surface of the feed needle, which receives and reliably carries one or two weft threads together. The feed needle can be translated or rotated on a circular path from the receiving position of the feed needle for receiving the active weft thread in the feed position to the transfer position of the feed needle for bringing at least one weft thread to the transfer position to the rapier.

The active clamp is brought into an open position after delivery of the active weft thread to the rapier, thereby releasing at least one active weft thread for weft insertion. The clamp can be opened during delivery to the rapier or after delivery to the rapier.

The clamp is preferably operable via an actuator. In particular, the clamp can be moved by the actuator from a closed position, in which the weft thread is securely clamped, to an open position. In a first configuration, the actuator is arranged stationary in the weft thread supplying device. The actuator is configured so that the active clamp, which is respectively located in the feed rotation position, is operable. The clamp can be brought from the closed position to the open position and/or from the open position to the closed position by the actuator. The configuration with a stationary actuator includes at least one actuator. In this case, the clamp rotates relative to the stationary actuator when the clamp disk rotates. In the feed rotation position, the active clamp is at least open, so that the weft thread can be released and inserted. In the case of only one actuator, the feed rotation position of the clamp corresponds to the storage rotation position of the clamp, whereby the active clamp is brought by the actuator to the open position in order to release the active weft thread before the weft thread insertion and to store the active weft thread after the weft thread insertion. The delivery and storage rotation positions are located near the joining point so that the active weft can be stored by the clamp after weft insertion.

Preferably, the weft feeder has a stationary second actuator. The stationary second actuator is preferably arranged so that the clamp, which is located in a storage rotation position different from the delivery rotation position, is operable. The storage rotation position is rotated in a direction toward the binding point of the woven fabric or a straight line along the binding point of the woven fabric, relative to the delivery rotation position. In the configuration with two actuators, the delivery rotation position of the active clamp is optimized and rotated away from the binding point of the woven fabric toward the direction of the rapier's motion path. After insertion, the active weft is received in the storage rotation position by the active clamp. This clamp is the same clamp from which the weft thread was removed in the delivery rotation position before the weft insertion. During weft insertion, the active clamp is rotated toward the binding point of the woven fabric. Due to the optimized delivery rotation position, in which the active clamp is positioned closer to the rapier during the transfer of the active weft thread to the rapier, the distance between the active clamp and the rapier clamp is shortened, which reduces the projection of the thread at the rapier clamp. This reduces the amount of lint in the form of thread protrusions that are transferred from the transfer rapier to the receiving rapier during weft insertion with the active weft and are pulled beyond the woven fabric.

If only one stationary actuator is used, it is sufficient to open the active clamp before weft insertion and close it after the active weft has been accommodated again after weft insertion in order to clamp the active weft securely. If at least two stationary actuators are used to operate the clamp, the active clamp is opened in the delivery rotation position for the transfer of the weft before weft insertion and closed again, then opened again in the accommodation rotation position to accommodate the weft after weft insertion and closed again to clamp the accommodated weft.

In an alternative configuration, each clamp is assigned a specific actuator. In this configuration, the actuator is fixedly attached to the clamping disk and rotates together with the clamp when the clamping disk rotates. The number of actuators corresponds to the number of clamps. In this respect, the configuration with a specific actuator for each clamp has the advantage that the operation of the respective clamp is not limited to discrete rotation positions of the clamping disk or clamp, in particular the delivery rotation position and/or the storage rotation position, but rather the operation of the clamp during the rotation process of the clamping disk can also be realized. Furthermore, the clamps can remain open even during rotation, for example between the transfer before the weft insertion and the storage after the weft insertion, which reduces the number of opening and closing processes and thus the mechanical load of the individual components and possibly the cycle time.

Preferably, the clamp is configured as a clamp that is closed in the normal state. This clamp is also usually referred to as a "normally closed" clamp. For this purpose, a preload force is applied to the clamp so that it is held closed and securely clamps the weft thread. Preferably, the clamp is held in the closed position by a spring, in particular a coil spring. The clamping force of the clamp is adjustable via the spring force or the spring preload. By varying the spring preload, the clamping force can be adjusted, which may be necessary in particular for different weft threads as well as weft thread materials and weft thread thicknesses. A change in the clamping force may also be necessary if, instead of one weft thread, it is desired to securely hold two or more weft threads per clamp.

At least one actuator operates the clamp, preferably pneumatically, electrically, mechanically or magnetically. The type of actuator or the operation of the clamp by the actuator is independent of whether the actuator is a stationary actuator or a non-rotatable actuator. In the case of a non-rotatable actuator, the actuator may be integrated into the clamp.

Preferably, a thread return device is further provided, which returns the weft thread after the weft insertion into the active clamp, i.e. the clamp from which the weft thread was removed. As thread return device, in particular a device serves which guides the weft thread reliably into the clamp, in particular into the clamping region of the clamp, in particular after the insertion, and thus reliably clamps the weft thread. For this purpose, the thread return device has, for example, a sickle-shaped region in which the weft thread is received and guided. The sickle-shaped region can be formed in the shape of a circular arc or, for example, in the shape of a U or V. The receiving region performs a movement during the return process, in particular in the direction of the clamp. In this case, the receiving region of the thread return device reciprocates, for example, on a circular or elliptical path of movement, and the inserted weft thread is guided exclusively over the region of the path of movement.

In a preferred configuration, the weft feed device has a clamp cleaner for cleaning the clamps after the weft transfer or before the weft transfer. The clamp cleaner is accordingly arranged in such a way that it can be operated in the open position of the clamp and cleans the clamps in the open position. The clamp cleaner can be arranged stationary in the weft feed device, just like the actuator. Preferably, the clamp cleaner is arranged in such a way that the active clamps can be cleaned in the delivery rotation position or the storage rotation position of the clamp disk. If the delivery rotation position is different from the storage rotation position, the clamp cleaner can be formed either in the delivery rotation position or in the storage rotation position. Alternatively, the clamp cleaner is arranged non-rotatably relative to the clamp disk or to the respective clamp. In this case, a clamp cleaner is arranged in each clamp, so that cleaning in the open position of the active clamp between the weft transfer and the weft storage is possible. Particularly preferably, the clamp cleaner is combined with a pneumatic operation of the clamp, i.e. at least one pneumatic actuator. Compressed air provided for the actuator can be used for the clamp cleaner. The clamp cleaner is preferably configured to be stationary or non-rotatable, depending on the configuration of the actuator. During clamp cleaning, dirt, such as residual yarn or lint, is removed from the clamp, ensuring reliable clamping of the weft yarn.

Preferably, the color selection disk and the clamping disk are arranged parallel to each other. More preferably, the rotation axis of the color selection disk and the rotation axis of the clamping disk are arranged coincident with each other, i.e., the color selection disk and the clamping disk are arranged concentrically with respect to a common rotation axis. Preferably, the clamps of the clamping disk and the holes of the color selection disk are arranged on part circle diameters that are preferably the same.

In a preferred configuration, the weft threads run parallel to one another between the color selection disc and the clamping disc. In each case, the individual weft threads run directly and straight from the holes in the color selection disc to the clamps in the clamping disc, i.e. without deflection, insofar as they are passive weft threads that, unlike the active weft threads, are not involved in the active weft insertion. That is to say, for example, the active weft threads are deflected around the recesses of the feed needles by being brought into the transfer position by the feed needles.

Preferably, the clamping disc and/or the color selection disc are rotated by an electric motor, in particular a stepping motor or a servo motor. Preferably, both the clamping disc and the color selection disc have their own drive, in particular an own electric motor. Furthermore, preferably, the color selection disc is driven or rotated synchronously with respect to the clamping disc. This reduces the deflection of the weft thread and thus also the load on the weft thread, which leads to a reduction in defects in the woven fabric.

The synchronous drive of the color selection disk and the clamping disk can alternatively be realized by a single drive, which drives both the color selection disk and the clamping disk. The color selection disk and the clamping disk are usually rotated at least if a different weft thread is required for the subsequent weft insertion than in the previous weft insertion. Preferably, the rotation of the color selection disk takes place between two successive weft insertions. In the case of the clamping disk, it may also be necessary to rotate the clamping disk between the weft transfer and the weft storage, if it is desired that the weft thread is stored in a position other than the position at which it was transferred. This is the case when the delivery rotation position is different from the receiving rotation position.

The present invention further includes a loom having the above-mentioned weft supplying device. Preferably, the clamping disks of the weft supplying device are arranged parallel to the warp threads of the woven fabric.

Preferably, weft scissors are arranged between the clamping disks and the warp threads, more preferably parallel to the warp threads. The weft scissors are in particular electronically or mechanically controlled. Preferably, the control takes place by the main drive of the weaving machine via a separate drive, in particular via a separate electric motor, or via a mechanical transmission, for example as an auxiliary drive.

The preferred embodiment and details of the present invention are described below with reference to the drawings.

1 is a diagram showing a first embodiment of a weft supplying device according to the present invention for a loom; FIG. FIG. 2 is a detailed view of the weft supplying device according to the present invention shown in FIG. 1 . FIG. 1 shows a first embodiment of a clamping disc according to the present invention. FIG. 2 shows a second embodiment of a clamping disc according to the present invention. FIG. 4 is a diagram showing a second embodiment of a weft supplying device according to the present invention; 3 shows a third embodiment of a weft feed device according to the invention, which introduces a double weft thread without twisting; FIG. FIG. 4 shows a fourth embodiment of a weft thread supplying device according to the invention with a double disc;

1 and 2 show a region of a weaving machine 1 with a woven cloth 3 and a weft thread supplying device 10 according to the invention, and FIG. 2 shows a partial region of the woven machine shown in FIG. 1 in a second state. Via the weft thread supplying device 10, the rapier 50 is supplied with the usable weft thread 2 from the plurality of weft threads 2a-h, which are introduced from the rapier 50 into the shed 4 for producing the woven cloth 3. In the weft thread supplying device 10, in the present embodiment, eight weft threads 2a-h are stored and can be selectively supplied to the rapier 50. The different weft threads 2a-h are in particular weft threads made of different materials or weft threads of different colors and/or weft threads of different thicknesses. Due to a predefined supply sequence of the weft threads 2a-h in conjunction with the predefined closing or opening positions of the individual shafts of the weaving machine 1, the woven cloth 3 can be woven in a predefined structure or in a predefined pattern.

The weft feeder 10 has a color selection disk 20, a clamping disk 40 and an input needle 30 arranged between the color selection disk 20 and the clamping disk 40 for selective feeding. The color selection disk 20 has eight holes 21a-h open outwardly on its outer diameter. The number of holes corresponds at least to the number of weft threads 2a-h or weft bundles to be individually fed to the rapier 50. The open holes 21a, 21c-h are closed by a latch in the form of a sliding guide disk 22, so that the weft threads 2a, 2c-h cannot be withdrawn from the corresponding open holes 21a, 21c-h. The color selection disk 20 is in a rotation position 12b in Figs. 1 and 2, whereby the open hole 21b is in the input rotation position 12 and constitutes an open active hole 21 that is not closed by the sliding guide disk 22. For this purpose, the sliding guide disk 22 has an arc-shaped sliding guide groove 25, the outer edge of which has an opening for releasing the active weft thread 2. Thus, the active weft thread 2 to be introduced, in the illustrated example, the weft thread 2b, can be received by the supply needle 30 located at the receiving position 31 as shown in FIG. 1 and guided by the supply needle to the transfer position 32 for transfer to the rapier 50. For this purpose, the supply needle 30 has a recess 33 on its front side for receiving the weft thread to be introduced. The active weft thread 2 brought to the transfer position 32 can be captured by the rapier 50 using its rapier clamp 51 and introduced into the shed 4.

The clamping disc 40 of the weft feeder 10 includes, on a partial circle diameter, a number of clamps 41a-h that corresponds to the number of open holes 21a-h of the color selection disc 20. In this embodiment, the color selection disc 20 includes eight open holes 21a-h and the clamping disc 40 includes eight clamps 41a-h, each open hole 21a-h or each clamp 41a-h being occupied by one of the weft threads 2a-h. Each weft thread 2a-h therefore extends through one of the open holes 21a-h and is clamped in the clamp 41a-h. The clamping disc 40, like the color selection disc 20, is shown in the rotational position 12b, so that the clamp 41b and the hole 21b are in the input rotational position 12 and the weft thread 2b is in the input position 11.

The weft thread supplying device 10 further has two stationary actuators 49, 49', the first actuator 49 being arranged so that the active clamp 41 located in the delivery rotation position 12 is operable, and the second actuator 49' being arranged so that the active clamp 41 located in the storage rotation position 14 is operable. The delivery rotation position 12 is optimized in the direction towards the rapier 50 by being different from the storage rotation position 14 due to the two actuators 49, 49'. This therefore shortens the distance between the active clamp 41 and the rapier 50, and therefore the thread projection 6 on the rapier 50.

The attachment of the weft threads 2a-h in the clamps 41a-h of the clamping disc 40 allows the individual weft threads 2a-h to be held without catch ears and to be provided with a defined preload for the feed needle 30. The color selection disc 20 can be driven in rotation via a first servo motor 23. The clamping disc 40 can be driven in rotation via a third servo motor 46 as a clamping disc drive. The feed needle 30 can be driven in translation via a second servo motor 34, so that it can bring the active weft thread 2 from the feed position 11 to the transfer position 13.

In the illustrated embodiment, the clamping disc 40 is arranged parallel to the warp threads 5 of the woven fabric 3. The partial circle diameter at which the weft threads 2a-h are held by the clamps 41a-h in the clamping disc 40 substantially corresponds to the partial circle diameter at which the holes 21a-h in the color selection disc 20 are located. The rotation axis 24 of the color selection disc 20 forms a straight line inclined relative to the rotation axis 42 of the clamping disc 40.

To select one of the multiple weft threads 2a-h and introduce it into the shed 4, both the color selection disk 20 and the clamping disk 40 are first brought into one of the multiple rotational positions 12a-h, so that the active weft thread 2 to be introduced is located at the feed position 11. The color selection disk 20 and the clamping disk 40 are rotated synchronously. The individual clamps 41a-h are mounted on the clamping disk 40 offset from one another by a predefined angle. The pitch between the individual clamps 41a-h can be constant or can vary. In order to bring the weft thread 2a-h held in one of the multiple clamps 41a-h into the feed position 11 in each case, the clamping disk must be rotated to the respective rotational position 12a-h. This also applies to the color selection disk 20 and the holes 21a-h. In Figures 1 and 2, weft thread 2b is the active weft thread 2, and both the color selection disc 20 and the clamping disc 40 are shown as being in rotational position 12b.

The weft thread 2 to be introduced is brought from the input position 11 to the transfer position 13 by the input needle 30. At the transfer position 13, the weft thread 2 to be introduced is received by the rapier 50. For this purpose, the rapier 50 captures the weft thread 2 to be introduced by the open rapier clamp 51, which is then closed to ensure that the weft thread 2 to be introduced is carried along with it. After the active weft thread 2 is transferred to the rapier 50, the active clamp 41 is opened by the actuator 49, which releases the weft thread 2 for insertion into the shed 4. Such a position of the rapier 50 after transfer is shown in FIG. 2. The weft thread 2 to be introduced is fixed in the rapier clamp 51. The illustrated rapier 50 is a transfer rapier that receives the weft thread 2 on the left side of the woven fabric 3 as the insertion side and transfers it to the center of the woven fabric. At the center of the woven fabric, the weft thread 2 is transferred to a receiving rapier (not shown) on the right side. The rapier clamp of the receiving rapier engages in the rapier clamp 51 of the rapier 50 and fixes the active weft thread 2. The active weft thread 2 is then transported through the entire shed 4. After weft insertion, the weft thread 2 to be introduced is introduced and clamped in the corresponding active clamp 41 from which it was removed. Similarly, the weft thread 2 is introduced back into the active hole 21 from which it was removed. To accommodate the weft thread 2 introduced by the active clamp 41, the clamp 41 is rotated in a clockwise direction to the accommodation rotation position 14 for the weft thread 2b. After the weft thread 2 is clamped in the corresponding active clamp 41, the weft thread 2 is cut by the weft scissors 60. Additionally, the active weft thread 2 is released from the clamp of the receiving rapier.

After the weft thread insertion has been performed, the same weft thread 2b or one of the other weft threads 2a, 2c-h can be selected for the subsequent weft thread insertion via the weft thread supplying device 10 and handed over to the rapier 50.

Figure 3 shows a first embodiment of a clamping disk 40 according to the invention. The clamping disk 40 has eight clamps 41a-h on a partial circle diameter. The individual clamps 41a-h are offset from one another by the same angle α in this embodiment. Clamp 41b is shown open and the clamping disk 40 is in rotation position 12b, so that clamp 41b is in the unloading rotation position 12. The number of clamps 41a-h can vary depending on the embodiment and depends in particular on the number of different weft threads 2a-h required for the woven fabric 3.

The clamps 41a-h are configured identically. By way of example, the structure of the clamps 41a-h is described with the clamp 41a. The clamp 41a comprises a base body 44, which is fixed to the clamping disk 40, in which a clamping element 45 is supported. The clamping element 45 has a shaft which is supported translatably in a bush in the base body 44. The clamp 41a is configured as a "normally closed" clamp and is closed in the normal state. For this purpose, the clamping element 45 is preloaded towards the base body 44 by a coil spring 48. The clamping force of the clamp 41a is adjustable via the force of the coil spring 48.

To bring the clamps 41a-h from the closed position to the open position, the weft supplying device 10 includes two actuators 49, 49' for operating the clamping elements 45. In the embodiment shown in FIG. 3, the two actuators 49, 49' are arranged in a stationary manner in the weft supplying device 10. Stationary is understood in this specification to mean that the actuators 49, 49' do not rotate together with the clamping disk 40. The first actuator 49 is arranged so that the active clamp 41, which is located in the unloading rotation position 12, is operable. In FIG. 3, the clamping disk is shown in the rotation position 12b. To this end, the actuator 49 operates the clamp 41b, which is brought from the closed position to the open position against the spring force of the coil spring 48. The actuator 49 includes a drive. The embodiment shown in FIG. 3 further includes a second actuator 49'. The second actuator 49' is arranged in a stationary manner so that the active clamp 41 is operable in the storage rotation position 14. The delivery rotation position 12 is rotated relative to the storage rotation position 14 in the direction of the line of weft insertion, away from the weft line or joining point of the active weft 2. In the figure, the delivery rotation position 12 is rotated counterclockwise relative to the storage rotation position 14.

Due to the different rotational positions when the effective weft thread 2 is handed over to the rapier 50 and when the effective weft thread 2 is stored after the weft thread is inserted, the thread protrusion 6 or waste length on the right side of the woven fabric 3, i.e., the side opposite the weft thread supply device 10, is reduced.

In the embodiment shown in FIG. 4, in contrast to the embodiment shown in FIG. 3, each clamp 41a-h is assigned its own actuator 49a-h. For this purpose, the actuators 49a-49h are not arranged stationary, but are connected to the clamping disk 40 in a non-rotatable manner, i.e., connected to rotate together with the clamping disk 40. The actuators 49a-h thus rotate together with the clamping disk 40, just like the clamps 41a-h. The assignment of one actuator 49a-h to each clamp 41a-h increases the flexibility when opening and closing the active clamp 41, and can therefore also result in time savings. In FIG. 4, the clamp 41b is brought into the open position by the actuator 49b and forms the active clamp 41. In the embodiment shown in FIG. 3, the active clamp 41 is opened twice for weft insertion. On the one hand, the clamp is opened by the actuator 49 before weft insertion for transfer, i.e., in particular when the rapier 50 has clamped the active weft 2, and then closed again. On the other hand, the active clamp 41 is opened by the actuator 49' to accommodate a new weft thread and closed again. In contrast to this, the active clamp 41 according to the embodiment shown in FIG. 4 can remain open between the handover before the weft thread insertion and the accommodation of the active weft thread 2 after the weft thread insertion, because the actuators 49a-h rotate together with the clamps 41a-h. Furthermore, whereas in the embodiment shown in FIG. 3 the operation of the clamps 41a-h is limited to two discrete rotational positions, in the embodiment shown in FIG. 4 the clamps 41a-h can be operated in any rotational position. Thus, for example, the operation of the clamps 41a-h can also be performed during the rotation of the clamping disc 40.

5 shows a second embodiment of the weft feeder 10 according to the invention with a clamping disk 40 and clamps 41a-h. The clamps 41a-h are mounted on the clamping disk 40 in a manner that is immovable relative to the clamping disk 40, as in the embodiment of the clamping disk 40 shown in FIG. 4. The structure and function of the clamps 41a-h essentially correspond to the embodiment shown in FIG. 3. In contrast to FIG. 3, the weft feeder 10 has only one stationary actuator 49. The delivery rotation position 12 therefore also coincides with the receiving rotation position 14. The weft feeder 10 additionally has a clamp cleaner 47, which blows out any remaining threads or waste yarn in the clamping area of the active clamp 41 with compressed air, so that a reliable clamping of the active weft thread 2 is always possible. The clamp cleaner 47 is shown by way of example in the form of a blowing tube in the area of the clamping part 41b. In this embodiment, the clamp cleaner 47 is fixedly arranged in the area of the storage rotation position 14, which in the illustrated embodiment also constitutes the delivery rotation position 12.

Furthermore, in the embodiment shown in FIG. 5, a thread returner 15 is shown. The thread returner is arranged to ensure that the active weft thread 2 is brought into the clamping area of the active clamp 41, here clamp 41b, after the weft thread insertion into the woven fabric 3. The thread returner 15 cooperates with the reed 7, whereby the thread returner 15 and the reed 7 return the inserted active weft thread into the active clamp 41. The thread returner has a drive 16. The movement of the thread returner 15 and the reed 7 is indicated diagrammatically by two movement arrows.

Figure 6 shows a third embodiment of the weft feeder 10 according to the invention, which introduces a double weft thread without twisting. The color selection disk 20 includes eight open holes 21a-h, and the clamping disk 40 has four clamps 41a-d. Each clamp 41a-d can be operated by an actuator 49a-d which is non-rotatable relative to the clamping disk 40, i.e. rotates together with the clamping disk 40. Each of the two weft threads guided in adjacent holes is held in a clamp. Thus, the weft thread 21a from the hole 21a and the weft thread 2b from the hole 21b are held in the clamp 41a. Both weft threads 2a,b therefore extend in a fan shape from the clamp 41a to the holes 21a,b. The same applies to the weft threads 2c, d, 2e, f and 2g, h, which are guided into the holes 21c, d, 21e, f and 21g, h, respectively, and are held in the clamps 41b, 41c and 41d. The supply needle 30 is formed with a double fork and has two recesses 33, which are arranged at a distance such that two adjacent active weft threads 2 can be captured by the supply needle 30 in the receiving position 31 and brought to the transfer position 32. In the illustrated drawing, the weft threads 2a, b are the active weft threads 2 located at the transfer position 13, and the supply needle 30 is located at the transfer position 32. The rapier 50 is designed in such a way that both active weft threads 2 are clamped in the rapier clamps 51 and introduced into the shed 4 without twisting. After the insertion of the double weft, both active weft threads 2 are again brought into the active clamp 41 by the reed 7 (not shown) and are clamped by this clamp 41.

FIG. 7 shows a fourth embodiment of the weft feeder 10 according to the invention with a color selection disk 20 having two partial disks 20', 20". Such an arrangement with two partial disks 20', 20" is also usually called a double disk. The weft feeder 10, like the embodiment shown in FIG. 1, has a clamping disk 40 with eight clamps 41a-h, in which one of the weft threads 2a-h is respectively held, and the weft feeder 10 has two stationary actuators 49, 49'. In contrast to the embodiment shown in FIG. 1, the color selection disk 20 consists of two partial disks 20', 20", which can rotate independently of one another and each have their own partial disk drive 23', 23". The two partial disks 20', 20" are arranged parallel to one another and can be pivoted about a common axis of rotation 24 in parallel pivot planes. If the definition for the insertion side of the woven fabric 3 is taken as the left side and the definition for the oppositely located side as the right side, then the weft insertion takes place from the left side to the right side. The first partial disc 20' in the weft insertion direction is away from the left side of the woven fabric 3 and is also called the rear partial disc. The second partial disc 20'' faces the left side of the woven fabric 3 in the weft insertion direction and is called the front partial disc. The first partial disc 20' has a larger diameter than the second partial disc 20''. The eight open holes 21'a-h of the first partial disc 20' are arranged on a partial circle diameter D. The four open holes 21''a-d of the second partial disc 20'' are arranged on a partial circle diameter d. The partial circle diameter D is larger than the partial circle diameter d. The color selection disc 20 has a total of 12 open holes, of which only eight holes are occupied by one weft thread out of the eight weft threads 2a-2h, respectively. The number of open holes and the number of occupied holes on the color selection disk 20, i.e., here the partial disks 20', 20'', can also generally vary depending on the embodiment and application.

The first partial disc 20' further has a passage 26 for the weft thread held in the open holes 21''a-d of the second partial disc 20''. The passage 26 is formed as an arc-shaped groove and has an outlet extending radially outward, so that the usable weft thread 2 can be presented to the rapier 50 by the presentation needle 30 if the weft thread 2 is held in one of the open holes 21''a-d. In the embodiment shown, the outlet is arranged centrally in the first partial disc 20' between the two open holes 21'd, 21'e. In addition to the arc-shaped slide guide groove 25 for the weft thread of the first partial disc 20', the slide guide disk 22 has a second arc-shaped slide guide groove 25' for the weft thread of the second partial disc 20''. The configuration of the color selection disk 20 with two partial disks 20', 20'' allows the maximum angular range through which the color selection disk 20 must be rotated to select the active weft thread 2 to be reduced or, for the same rotation angle, the number of holes is increased. This can be particularly advantageous in weft feed devices 10 which also introduce double weft threads without twisting.

REFERENCE SIGNS LIST 1 loom 2 active weft thread 2a-h weft thread 3 woven fabric 4 shed 5 warp thread 6 thread projection 7 reed 10 weft feeder 11 active weft thread presentation position 12 presentation rotation position 12a-h rotation position 13 active weft thread transfer position 14 storage rotation position 15 thread returner 16 thread returner drive 20 colour selection disc 20' first partial disc 20'' second partial disc 21 active hole 21a-h open hole 21'a-h open hole of first partial disc 21''a-d open hole of second partial disc 22 latch in the form of a sliding guide disc 23 first servo motor 23' first partial disc drive 23'' second partial disc drive 24 rotation axis of colour selection disc 25, 25' sliding guide groove 26 Pass-through portion 30 Feeding needle 31 Feeding needle receiving position 32 Feeding needle delivery position 33 Recessed portion 34 Second servomotor 40 Clamping disc 41 Active clamp 41a-h Clamp 42 Rotation axis of clamping disc 44 Base body 45 Clamping element 46 Third servomotor 47 Clamp cleaner 48 Coil spring 49, 49' Stationary actuator 49a-h Non-rotatable actuator 50 Rapier 51 Rapier clamp 60 Weft scissors

Claims (17)

A weft supplying device (10) that provides a plurality of wefts (2a-h) in a loom (1) and selectively supplies a usable weft (2) to a rapier (50), comprising:
a) a rotatably drivable color selection disk (20) having a number of holes (21a-h) arranged on its outer circumferential surface, each of which accommodates at least one weft thread (2a-h);
b) a rotatably drivable clamping disc (40) provided with a number of clamps (41a-h) arranged on its outer circumferential surface and holding at least one weft thread (2a-h) in each case in the closed position;
c) an input needle (30) arranged between the color selection disk (20) and the clamping disk (40), through which the at least one active weft thread (2) to be supplied can be transferred from an input position (11) to the rapier (50) in a transfer position (13), the active clamp (41) being brought into an open position after the transfer, the input position (11) being a position where the at least one active weft thread (2) can be reached by rotating the color selection disk (20) and the active clamp (41) together with the clamping disk (40) into an input rotation position (12). The weft supplying device (10) according to claim 1, characterized in that the clamps (41a-h) are operable via at least one actuator (49, 49a-h, 49'). The weft supplying device (10) according to claim 2, characterized in that the actuator (49) is arranged stationary and is capable of operating the active clamp (41) which is respectively located in the delivery rotation position (12). The weft supplying device (10) according to claim 2 or 3, characterized in that the active clamp (41) located in the storage rotation position (14) can be operated via a second actuator (49'). The weft supplying device (10) according to claim 2, characterized in that each clamp (41a-h) is assigned a unique actuator (49a-h), and the actuator (49a-h) is attached to the clamp disk (40) so as not to be able to rotate relative to the clamp disk (40). A weft supplying device (10) according to any one of claims 2 to 5, characterized in that the clamps (41a-h) are configured as closed clamps in a normal state. The weft supplying device (10) according to claim 6, characterized in that the clamps (41a-h) are each held in the closed position by a spring (48) and the clamping force of the clamps (41a-h) is adjustable via the spring force of each of the springs (48). The weft supplying device (10) according to any one of claims 2 to 6, characterized in that the at least one actuator (49, 49a-h, 49') pneumatically, electronically, mechanically or magnetically operates the clamps (41a-h). The weft supplying device (10) according to any one of claims 1 to 8, further comprising a thread returner (15) for returning the at least one active weft thread (2) into the active clamp (41) from which the at least one active weft thread (2) was removed after weft insertion. The weft supplying device (10) according to any one of claims 1 to 9, characterized in that a clamp cleaner (47) is provided for cleaning the clamps (41a-h) after the delivery of the at least one usable weft (2) to the rapier (50). A weft supplying device (10) according to any one of claims 1 to 10, characterized in that the color selection disk (20) and the clamping disk (40) are arranged parallel to each other, in particular concentrically with respect to one shared axis of rotation (24, 42). A weft thread supplying device (10) according to any one of claims 1 to 11, characterized in that the weft threads (2a-h) extend parallel to each other between the color selection disc (20) and the clamping disc (40). The weft supplying device (10) according to any one of claims 1 to 12, characterized in that the clamping disc (40) can be rotated by an electric motor, in particular a stepping motor or a servo motor. A weft supplying device (10) according to any one of claims 1 to 13, characterized in that the color selection disk (20) is driven synchronously with respect to the clamping disk (40). A loom (1) equipped with a weft supplying device (10) according to any one of claims 1 to 14. The loom (1) according to claim 15, characterized in that the clamping discs (40) are arranged parallel to the warp threads (5). The loom (1) according to claim 15 or 16, characterized in that a weft scissors (60) is arranged between the clamping disc (40) and the warp threads (5) parallel to the warp threads (5), and the weft scissors (60) are electronically or mechanically controlled.

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