EP1888825B1

EP1888825B1 - Terry loom and modular terry loom appliance

Info

Publication number: EP1888825B1
Application number: EP06743118A
Authority: EP
Inventors: Karl-Heinz Baukmann; Paul Van Coillie
Original assignee: Picanol NV
Current assignee: Picanol NV
Priority date: 2005-06-10
Filing date: 2006-06-07
Publication date: 2011-02-23
Anticipated expiration: 2026-06-07
Also published as: EP1888825A1; DE102005028126A1; CN101194058A; DE602006020270D1; BRPI0613490B1; BRPI0613490A2; WO2006131323A1; CN101194058B; BRPI0613490B8; ATE499470T1

Abstract

In the case of a terry loom with a drive (26) for moving backrest (14) and breast beam (23) to and fro, provision is made for the drive (26) to comprise its own drive motor (31), which drives a shaft (33) which is connected to the holding elements (28, 30) of backrest (14) and breast beam (23) by means of transmission elements (37, 38).

Description

The invention relates to a terry loom according to the introductory part of claim 1.
Terry looms of the above-mentioned type have long been known, for example from US 607 377 or from US 15 95 289 . The to-and-fro motion of backrest and breast beam moves the cloth being produced relative to the device for beating up the weft yarns, in particular a reed, such that the distance from the fell of the cloth being produced to the beat-up line of the reed varies. If, after a plurality of picks and beat-ups effected at a distance from the beat-up line, the cloth is displaced, so moving the fell closer to the beat-up line, the previously inserted weft yarns are carried towards the fell in the next beat-up. In the process, they move relative to the more tightly tensioned warp yarns of the ground warp, while carrying with them the only loosely tensioned warp yarns of the pile warp. In the process, the warp yarns of the pile warp form loops. The drive which moves backrest and breast beam to and fro comprises an eccentric cam driven by the main shaft of the loom, which eccentric cam is connected to the holding elements of backrest and breast beam via a transmission linkage. The element driven by the eccentric cam is held on the eccentric cam by means of spring force. Such drives are only suitable for relatively low speeds and for cloths with simple terry weaves.
It is additionally also known, in particular from EP 03 50 446 A1 , Figs. 9 and 10, to arrange backrest and breast beam in a common frame, which may be displaced to and fro in the weaving direction by means of a drive. This drive comprises a servomotor. It is further known from EP 03 50 446 A1 Fig. 11 to hold both the ground warp backrest and the breast beam and a temple by means of swivel levers, which may be swivelled by means of servomotors in order to move the cloth relative to the device for beating up the weft yarns. In both embodiments the ends of the swivel levers are provided with teeth, in which there engages a worm wheel seated on the shaft of the servomotor(s), so providing a self-locking transmission. Such drives are not well suited to higher speeds.
The object of the invention is to improve a terry loom of the above-mentioned type in such a way that a simplified drive is obtained which allows high speeds and is suitable for any type of terry cloth.
This object is achieved by the features of claim 1.
The invention realizes a direct drive, in which the rotational movement of the drive motor is converted directly into a movement of the backrest and breast beam holding elements. The drive additionally allows very considerable freedom with regard to the design of the pattern and to weaving processes. Since the motor may effect movement to any desired position, it is straightforwardly possible to change pile height, i.e. even during weaving. It is straightforwardly possible to transfer from a flat cloth to a terry cloth and vice versa. It is also possible to change the number of picks between full beat-ups.
The invention also relates to a terry loom device which takes the form of a module and may be added onto a loom to convert it into a terry loom.
Further features and advantages of the invention are revealed by the following description of the embodiment illustrated in the drawings and by the dependent claims.

Fig. 1: is a schematic representation of a terry loom according to the invention,
Fig. 2: is a perspective representation of the drive for moving the backrest and breast beam of the loom and thus the cloth to and fro,
Fig. 3: is a view similar to Fig. 2 of a modified embodiment,
Fig. 4: is a view similar to Fig. 2 of a further modified embodiment and
Fig. 5: is a view similar to Fig. 2 of an embodiment with two drive mo- tors.

The terry loom illustrated schematically in Fig. 1 has a warp beam 10 with a ground warp 11 and a warp beam 12 with a pile warp 13. The ground warp 11 is deflected into the substantially horizontal weaving plane via a backrest 14. The pile warp 13 runs over a preferably flexible deflector 15 to its own backrest 16 and thence likewise into the weaving plane. Ground warp 11 and pile warp 13 travel to shedding devices 17 indicated with arrows. Upstream of the deflector 15 there is provided a deflector 47.
Weft yarns are inserted in each case into the sheds. The device for inserting weft yarns may take the form, for example, of an air-jet loom insertion device. This conventionally has two main blowing nozzles arranged one behind the other and next to the shed and a row of relay nozzles, which are arranged on a sley 18 and whose blowing direction is directed towards a weft insertion channel of a reed 19. The reed 19, which together with the swivellably driven sley 18 forms a device for beating up the weft yarns, brings the inserted weft yarns to a beat-up line. At this beat-up line, these weft yarns are tied up by means of the warp yarns when the shed is changed, i.e. the shedding device 17 changes a number of warp yarns from the upper position into the lower position and a number of warp yarns from the lower position into the upper position. The cloth 20 formed in this way is drawn off by means of a draw-off roller 21 and wound onto a cloth beam 22. A breast beam 23 and two deflectors 24, 25 are arranged upstream of the driven draw-off roller 21. The breast beam 23 deflects the cloth 20 downwards out of the substantially horizontal weaving plane. The draw-off roller 21 takes the form of a sand roller or needle beam.
The backrest 14 of the ground warp 11 and the breast beam 23 may be moved to-and fro in the same direction substantially in the weaving plane by a drive device 26. The backrest 16 of the pile warp 13 is held in resiliently compliant manner substantially in the weaving plane, for example. Through the to-and-fro motion of backrest 14 and breast beam 23, the warp yarns of the ground warp 11 and the pile warp 13 and the woven cloth 20 are likewise moved to and fro, such that the distance between the fell 27 and the beat-up line of the reed 19 varies, i.e. the distance to the line towards which the sley 18 moves during beating up of a weft yarn in the direction of the fell 27. Provision is made, for example, for the fell 27, after beating up of a weft yarn to said fell 27, to be moved away from the beat-up line by moving backrest 14 and breast beam 23 accordingly, i.e. to the left in Fig. 1. This position of backrest 14 and breast beam 23 and thus of the fell 27 is maintained for example during the next two to four picks and beating up thereof. Then the cloth 20 with the fell 27 is moved back closer to the reed 19 by moving backrest 14 and breast beam 23 accordingly, i.e. to the right in Fig. 1. When the last inserted weft yarn is beaten up in this position of the cloth 20, said weft yarn is brought up to the fell 27 with the previously inserted weft yarns. In the process, the weft yarns slide along the warp yarns of the ground warp 11, which is relatively tightly tensioned. The warp yarns of the pile warp 13, which is less tensioned, are carried along by the weft yarns during the beating-up movement, such that the warp yarns of the pile warp 13 are formed into loops, which project upwards and/or downwards from the surface consisting of ground warp 11 and weft yarns.
The backrest 14 of the ground warp 11 is mounted on a swivel lever 28, which may be swivelled about a shaft 29 parallel to the backrest 14. The shaft 29 carries a roller-shaped deflector for the warp yarns of the ground warp 11, which travel to the backrest 14. Attached to the swivel lever 28 is a lever 42, which is held by a spring 43. The lever 42 forms a holding element for the backrest 14 of the ground warp 11. The swivel lever 30 forms a holding element for the breast beam 23 and may be swivelled about the shaft of the deflector 24, which extends parallel to the breast beam 23.
The swivel levers 28 and 30 are driven by means of a drive motor 31, more particularly a stepping motor. The drive motor 31 is connected via a reduction gear 32 to a shaft 33, which extends parallel to the backrest 14 and breast beam 23. The reduction gear 32 has an input which is coaxial with its output, such that drive motor 31 and shaft 33 are likewise coaxial with one another. The shaft 33 is mounted by means of bearing elements 34, which may be attached to side parts, not shown, of the loom frame. The casing of the gear 32 is attached to one of the bearing elements 34.
Two swivel arms 36 are connected for rotation with the shaft 33, said swivel arms being arranged on the shaft 33 at a spacing corresponding to the cloth width. A pair of transmission bars 37 are coupled to the swivel arms 36, said bars being connected to the swivel levers 28 which carry the backrest 14. The swivel arms 36 are connected via a further pair of transmission bars 38 to the swivel levers 30 of the breast beam 23. The transmission bars 38 have an upwardly bowed profile, such that the area of the fell 27 of the cloth 20 is freely accessible. In this area there are additionally conventionally located auxiliary units such as for example cutting devices for the weft yarns, selvage tuck-in devices and temples.
As is clear from Figs. 1 and 2, the transmission bars 37 which lead to the swivel levers 28 of the backrest 14 are arranged at a smaller radial distance from shaft 33 than the transmission bars 38 which lead to the swivel levers 30 of the breast beam 23.
The reduction gear 32, which is arranged between the drive motor 31 and the shaft 33 and comprises only gearwheels rotatable about axes parallel to the shaft 33, has no self-locking capacity. The forces acting on the backrest 14 and the breast beam 23 have the effect that the transmission bars 37, 38 with the swivel levers 28, 30 always adopt an intermediate position which is located between the end positions, i.e. the position in which the fell 27 is located closest to the reed 19 and the position in which the fell 27 is furthest away from the reed 19 and the beat-up line.
The dimensions and geometric arrangements of the individual elements are such that the forces arising balance each other to a considerable extent, such that in the case of a drive motor at zero current the above-mentioned intermediate positions are maintained. As is clear from the illustrations, the transmission bars 38 are arranged for this purpose, for example, at a greater distance from the axis of the shaft 33 than the transmission bars 37. No restoring forces, which would have to be overcome by the drive motor 31, act on the swivel levers 28, 30 and the transmission bars 37, 38 and on the shaft 33. The drive motor 31 has therefore to exert only relatively small forces in order to achieve high weaving speeds. The balanced forces, which allow stopping in intermediate positions, result in good efficiency and correspondingly low energy consumption in addition to elevated weaving speeds.
The drive motor 31 is freely programmable and may effect movement into positions which are determined by its control device, but not by just any limit stops or maximum deflection of an eccentric drive. The maximum position is determined solely by the control device of the drive motor 31. This makes it possible to change fell positions even during weaving, for example in order to weave areas with larger loops, areas with smaller loops or areas without loops and with only plain cloth. It is also possible to change the sequence of beat-ups at a distance from the fell 27 and not at a distance from the fell 27 during weaving.
In the exemplary embodiment according to Fig. 3, the deflector 15 arranged upstream of the backrest 16 of the pile warp 13 may likewise be moved to and fro by means of the drive 26. To this end, a further pair of transmission bars 39 is attached to the swivel arms 36. The transmission bars 39 act on a pair of two-armed levers 44, which are swivellable about coaxial shafts 45. The second arms of the levers 44 comprise bearings 46, which hold the deflector 15 of the pile warp 13. The two-armed levers 44 are driven by the transmission bars 39 in such a way that the deflector 15 moves in the opposite direction to the backrest 14 and the breast beam 23, i.e. if the latter two move to the left, the deflector 15 moves to the right and vice versa. Between the two-armed lever 44 and the transmission bars 39 there are provided adjusting elements 67, such that the magnitude of the path travelled by the deflector 15 may be adjusted relative to the angular movement of the swivel arms 36. The deflector 15 is flexible, as has already been mentioned. It has a carrier bar 64, to which a substantially cylindrically shaped spring steel sheet 65 is attached by connecting elements 66, for example screws.
One embodiment of the invention provides that the backrest 16 of the pile warp 13 is held resiliently in such a way that it may move substantially in the weaving plane. Such a holder 53 comprises for example a support 56, which is held by leaf spring assemblies 57, as is described in the parallel German patent application with internal file reference 10 2005 028 127.3 . Another embodiment provides that the drive 26 also moves the backrest 16 of the pile warp 13 to and fro. To this end, similar as in the illustration in Fig. 3, a further pair of transmission bars is then attached to the swivel arms 36, said bars acting directly on the backrest 16 of the pile warp 13 or on swivel levers which hold the backrest 16.
The drive motor 31 may be controlled for each pick by a program, and this not only with regard to the magnitude of the movement, but also with regard to the beginning and end of the movement within a weaving cycle. It is merely sensible for the drive motor 31 to adopt a defined position when a weft yarn is beaten up. During the remaining part of a weaving cycle, the drive motor 31 may in principle adopt any position. In a preferred configuration, provision is made for the movement of the drive motor 31 to begin approximately at 120° of the loom main shaft, before the beat-up position is reached. The drive motor 31 may then rotate for example through 60 angular degrees, such that the shaft 33 is turned for example through 16 angular degrees via the reduction gear 32. These angular values may of course assume other values, e.g. the drive motor 31 may rotate through 600 angular degrees for obtaining a rotation of 20 angular degrees of the shaft 33. The magnitude of the angular movement of the drive motor is determined substantially on the basis of the desired pile height. The movement profile of the drive motor 31 is determined substantially on the basis of loom speed. For example, the shaft 33 may be moved between 0 and 16 angular degrees in order to achieve a pile height of between 0 mm and 20 mm. This angular range may of course be selected and assume other values.
Fig. 4 shows an embodiment of a drive 26 in which the transmission bars 37, 38 and/or the swivel arms 36 on both sides of the machine are connected together extensively rigidly, such that a connecting shaft 33 (Fig. 2) may be dispensed with. The swivel arms 36, which are arranged at a spacing adapted to the cloth width, are arranged coaxially with an axis 51. They are connected together by a connecting bar 52, such that the movement of the drive motor 31 is transmitted to the opposing swivel arm 36. Instead of the connecting bar 52 or optionally in addition to the connecting bar 52, it is possible for the swivel levers 28, 30 to be connected to one or more connecting bars 55, 54, so resulting in a rigid frame.
In the embodiment according to Fig. 5, two swivel arms 36 are arranged coaxially with one another at a spacing adapted to the cloth width. The two swivel arms 36 are driven in each case by their own drive motor 31A, 31B and their own reduction gear 32A, 32B. The two drive motors 31 A and 31B are synchronised electronically with one another by means of an open and closed loop control device 60. The open and closed loop control device transmits drive signals 61, 62 to the drive motors 31A, 31 B, which send back to the open and closed loop control device 60 status signals 63, 64 relating to the position of the drive motors 31A, 31 B. The drive motors can, for example, be a stepping motor used in a feedback control system or a servomotor.
The invention offers the possibility of combining the devices for supplying a ground warp 11 and a pile warp 13, the devices for drawing off the cloth produced, the drive 26 for moving backrest 14 and breast beam 23 to and fro and the associated holding elements 28, 30 in the form of a modular terry loom appliance. It is then possible, by means of this terry loom appliance, to convert a normal loom, which comprises shedding devices, a device for inserting weft yarns and a device for beating up weft yarns, into a terry loom.
As has already been mentioned, the arrangement of the transmission elements 36, 37, 38 and the holding elements 28, 30 is such that the drive motor 31 may remain in any position when at zero current, since the forces exerted by the warp yarns 11, 13 and by the cloth 20 on the drive motor 31 are extensively balanced. The drive motor 31 may thus remain in any position when it is switched to zero current or when a relatively small holding current is provided. If no holding current is provided, the drive motor 31 adjusts itself into a position in which the forces of the warp yarns 11, 13 and the forces of the cloth 20 cancel each other out.
It goes without saying that the terry loom is not restricted to air-jet loom weft insertion devices. It goes without saying that weft insertion devices may also be used such as those known in rapier looms, projectile looms, shuttle looms, gripper shuttle looms, water jet looms or any other type of loom. If the terry loom appliance takes the form of a module, it may be installed in any of these types of loom.
The invention is not restricted to the exemplary embodiment illustrated, but instead modifications are straightforwardly possible. In particular, another spatial arrangement of pile warp beam 12 and ground warp beam 10 may be adopted. Likewise, other holding elements which allow movement substantially in the weaving plane may be provided for the backrest 14 and the breast beam 23 instead of swivel levers 28, 30. It is also possible to provide a common backrest for ground warp 11 and pile warp 13.

Claims

A terry loom with devices for supplying a ground warp (11) and a pile warp (13), to each of which is associated at least one backrest (14, 16), with a shedding device, with a device for inserting weft yarns, with a device (18, 19) for beating up the weft yarns, with a device (21, 23, 24, 25) for drawing off cloth (20), which comprises a breast beam (23), and with a drive (26) for moving backrest (14) of the ground warp and breast beam (23) to and fro, substantially in the weaving direction, wherein the drive (26) comprises at least one own drive motor (31, 31A, 31 B), which is connected to backrest (14) of the ground warp and breast beam (23) by means of transmission elements (36, 37, 38), characterised in that the drive motor (31, 31A, 31 B) drives a shaft (33) on which swivel arms (36) are fixed which rotate with the shaft (33) and to which pairs of transmission bars (37, 38) are attached which lead to holding elements (28, 30) of the backrest (14) of the ground warp and of the breast beam (23).
A terry loom according to claim 1, characterised in that a reduction gear (32, 32A, 32B) is arranged downstream of the drive motor (31, 31A, 31 B), said reduction gear(32) preferably having an output coaxial with the input.
A terry loom according to claim 1 or 2, characterised in that pairs of transmission elements (37, 38) are provided which are arranged spaced by a distance adapted to the cloth width.
A terry loom according to any one of claims 1 to 3, characterised in that a pair of parallel mounted swivel arms (36) are arranged at a spacing adapted to the cloth width, said swivel arms (36) being connected by means of transmission bars (37, 38) to the holding elements (28, 30, 44), wherein the swivel arms (36) and/or the transmission bars (37, 38) are connected together in the manner of a frame and wherein the drive motor (31) is assigned to one swivel arm (36).
A terry loom according to any one of claims 1 to 3, characterised in that a pair of parallel mounted swivel arms (36) are arranged at a spacing adapted to the cloth width, said swivel arms (36) being connected by means of transmission bars (37, 38) to the holding elements (28, 30), wherein a drive motor (31A, 31 B) is assigned to each swivel arm (36), said motors being electronically synchronised.
A terry loom according to any one of claims 1 to 5, characterised in that the holding elements of backrest (14) and breast beam (23) take the form of swivel levers (28, 30), which are swivellable about shafts (29, 24) parallel to the backrest (14) and to the breast beam (23).
A terry loom according to any one of claims 1 to 6, characterised in that a further pair of transmission bars is provided for connecting the swivel arms (36) to the backrest (16) of the pile warp (13).
A terry loom according to any one of claims 1 to 7, characterised in that a further pair of transmission bars (39) is provided for connecting the swivel arms (36) to a holder for a deflector (15) of the pile warp (13).
A terry loom according to any one of claims 1 to 8, characterised in that the transmission bars (38) to the breast beam (23) are coupled at a spacing from the axis of the swivel arms (36) which is greater than the spacing at which the transmission bars (37) to the backrest (14) are coupled to the swivel arms (36).
A terry loom according to any one of claims 1 to 9, characterised in that the drive motor (31) is a stepping motor.
A terry loom according to any one of claims 1 to 10, characterised in that a non self-locking reduction gear (32) is provided, and in that the transmission elements (36, 37, 38, 39) and the holding elements (28, 30, 44) are so configured and/or designed that the shaft (33) adopts a position between its two end positions when the drive motor (31) is at zero current.
A terry loom appliance for a loom which loom comprises devices for supplying a ground warp (11) and a pile warp (13), to each of which is associated at least one backrest (14, 16), and with a device (23, 24) for drawing off cloth (20), which comprises a breast beam (23), and with a drive (26) for moving backrest (14) of the ground warp and breast beam (23) to and fro, wherein the drive (26) comprises at least one drive motor (31; 31A, 31B) which may be connected to backrest (14) of the ground warp and to breast beam (23) by means of transmission elements (36, 37, 38), characterised in that the terry loom appliance takes the form of a module, which comprises at least one drive motor (31, 31A, 32B) driving a shaft (33) on which swivel arms (36) are fixed which rotate with the shaft (33) and to which pairs of transmission bars (37, 38) are attached which lead to holding elements (28, 30) of the backrest (14) of the ground warp (11) and of the breast beam (23).