Title of Invention	GUIDE ELEMENT FOR A GRIPPER TRANSPSORT ELEMENT OF A WEAVING MACHINE
Abstract	The invention relates to a guide element (10, 80) for a gripper transport element (19), of a weaving machine, comprising guides (14, 15, 16, 17, 18, 42, 87), forming a positive frame (13) for the gripper transport element, open on one side, wherein the frame (13) is provided with at least one projection (41) associated to a longitudinal groove on the lower side of the gripper transport element (19), which protrudes from a guide (14) of the frame (13) associated to the lower side of the gripper transport element (19), that the frame (13) at the open side adjoining the projection is provided with a shoulder (20), characterized in that the shoulder (20) is designed in form of a pike directed away from the frame (13), and whose upper edge (43) forms a guide for the gripper transport element (19), which is located below the upper edge (42) of the projection (41), and in that a projection (40) protrudes from the guide (16) associated to the upper side of the gripper transport element, which faces the protruding projection (41) from the guide (14), associated to the lower side of the gripper transport element (19), wherein the projections (40,41) leave a gap in between.

Title of Invention

GUIDE ELEMENT FOR A GRIPPER TRANSPSORT ELEMENT OF A WEAVING MACHINE

Abstract

The invention relates to a guide element (10, 80) for a gripper transport element (19), of a weaving machine, comprising guides (14, 15, 16, 17, 18, 42, 87), forming a positive frame (13) for the gripper transport element, open on one side, wherein the frame (13) is provided with at least one projection (41) associated to a longitudinal groove on the lower side of the gripper transport element (19), which protrudes from a guide (14) of the frame (13) associated to the lower side of the gripper transport element (19), that the frame (13) at the open side adjoining the projection is provided with a shoulder (20), characterized in that the shoulder (20) is designed in form of a pike directed away from the frame (13), and whose upper edge (43) forms a guide for the gripper transport element (19), which is located below the upper edge (42) of the projection (41), and in that a projection (40) protrudes from the guide (16) associated to the upper side of the gripper transport element, which faces the protruding projection (41) from the guide (14), associated to the lower side of the gripper transport element (19), wherein the projections (40,41) leave a gap in between.

Full Text	Description Guide element for a gripper transport element of a weaving machine The invention relates to a guide element for a gripper transport element of a weaving machine with guides that form a form-closed frame that is open on one side for the gripper transport element. Gripper transport elements consist of gripper rods or gripper bands that are introduced into a weaving shed from one side of the weaving machine. A gripper transport element moves a gripper, that has taken up a weft thread, either to the opposite side of the weaving shed, where the weft thread is taken over by a takeover element. Or the gripper transport element moves with the gripper and the weft thread to the middle area of the weaving shed, where it is likewise approached by a takeover gripper on a gripper transport element that takes over the inserted weft thread and then trans- ports the weft thread to the other side of the shed in a motion out of the weaving shed. Or the gripper transport element moves with a gripper, a take-over gripper, through the weaving shed and catches a weft thread that is then pulled through the shed. The gripper transport elements are guided within the shed by means of guide elements that are fixed on the slay. They move with the slay, whereby they penetrate into a warp-thread sheet from below, when the reed is moved away from the fell line of the cloth. They again move out of the shed through the lower warp-thread sheet, when the newly inserted weft thread is beaten up by the reed at the fell line of the cloth. Hook-shaped guide elements are known (EP 02 75 479 B1), whose open side faces the reed. They serve particularly for guiding a gripper transport element designed as a gripper band. They have a guide associated to the upper side of the gripper transport element and a guide associated to the opposite lower side of the gripper transport element. A further guide is pro- vided for a side surface of the gripper transport band, on the side facing away from the open side. The lower and/or upper guide engage in a longi- tudinal groove of the lower side and/or the upper side of the gripper band, whereby the sides of the guides, facing away from the open side, secure the gripper band against movement towards the open side. The guides for preventing the movement of the gripper band in the direction towards the open side are relatively small. This causes substantial abrasion on the guide elements and on the gripper transport elements in a relatively short time. C-shaped guide elements are also known (WO 94/10364), which are like- wise open towards the reed. The gripper transport element that in this case can also be a flexible gripper band is guided on the open side of the guide element by means of two opposite portions of guides, which prevent movement in the horizontal direction towards the reed. The upper side and the lower side of the gripper transport element keep a distance from the opposite portions of the guide elements, so that they are not guided. The gripper transport element has a section extending through the open side of the guide elements, which is guided in vertical direction between the opposite portions of the guides. Also with this type, in particular in the direction towards the reed, only relatively small guides are provided, so that rapid abrasion is expected. Further guides are known (EP 07 15 009 Al), which support a gripper band only on the lower side and thereby engage in a longitudinal groove of the lower side of the gripper band. The gripper band and the gripper are se- cured against lifting only by means of gravity. It is expected that such guide elements are not adequate in case of very high weaving speeds, since the gripper bands lift and/or are prone to kinking. The invention has the object to provide guide elements of the type men- tioned at the beginning, which improve the guidance of the gripper transport elements. This object is achieved in that, the frame is provided with at least a projection associated to a longitudinal groove of the lower side of the gripper transport element, and a shoulder adjoining the projection on the open side, whose upper edge forms a guide for the gripper transport element located below the upper edge of the projection. Since the frame encloses the gripper transport element with the guides that are associated to the upper side and to the lower side of the gripper trans- port element, relatively large guides are obtained without the dimensions having to be increased. It is even possible to reduce the size of the cross- sections of the gripper transport elements without having to reduce the size of the guides and guide surfaces. Smaller cross-sections lead to smaller masses and therefore allow higher weaving speeds. Particularly advanta- geous is the shoulder which projects from the frame to the open side. This shoulder on the one hand forms a support for a part of the gripper transport element located outside the frame so that the transport element can be sup- ported against torsional forces. Furthermore, the shoulder reduces the dan- ger that warp-threads get caught in the guide elements, which could lead to damage of the warp-threads and/or to warp-thread breaks. According to an advantageous embodiment of the invention, it is provided that, the shoulder is designed as a pike protruding away from the frame. This pike can be inserted between two warp-threads that have already been pushed apart by the upper edge of the guide elements. In a further embodiment of the invention, it is provided that, the upper edge of the guide element has a highest point that is located in the area above the open side of the frame. The upper edge of the guide elements first meets the warp-thread sheet and presses the warp-threads some- what apart. The shoulder lies in the "shadow" of the upper edge, so that it easily penetrates between the warp-threads that are already pushed apart. The danger that warp-threads will be caught is therefore signifi- cantly reduced. Likewise, the danger that warp-threads may contact the guides for the gripper transport element is reduced. Further features and advantages of the invention will become apparent from the following description of the embodiments illustrated in the accompanying draw- ings and in the dependent claims. Fig. 1 shows a perspective view of a guide element according to the invention, Fig. 2 shows a perspective view of the guide element according to Fig. 1 from the other side, Fig. 3 shows a schematic side view of the guide element according to Fig. 1 and 2 together with a gripper transport element guided therein, Fig. 4 shows a view of the guide element according to Fig. 1 to 3 with a gripper transport element at a different cross-section, Fig. 5 shows a schematic view of a further embodiment of a guide element with a gripper transport element in cross-section, Fig. 6 shows the guide element according to Fig. 5 with a modi- fied gripper transport element, Fig. 7 shows a perspective view on a further embodiment of a guide element, Fig. 8 shows a perspective view of the guide element of Fig. 7 from the opposite side, Fig. 9 shows a schematic view of the guide element according to Fig. 7 and 8 together with a gripper transport element in cross-section, Fig. 10 shows the view of the guide element according to Fig. 7 to9 with a gripper transport element at a different cross-section and Fig. 11 to 18 shows further embodiments of guide elements according to the invention. The guide elements shown in Fig. 1 to 18, like shown in EP 0576854 A1, are fixed on a slay that accommodates a reed as well. The slay executes to-and-from movements in order to beat up a weft thread at the cloth fell. Thereby, the guide elements are brought through the lower warp-thread sheet in a weaving shed, when the reed is in the rear position and a weft thread is inserted. To beat up the weft thread, the slay with the reed moves towards the cloth fell, whereby the guide elements, after the gripper transport element has been pulled back, again moves through the lower warp sheet out of the shed. In the drawings, only the position is shown in which the reed is located in the farthest position it moved back to and in which a gripper transport element is inserted into a shed. When the terms "upper" and "lower" are used, then they respectively refer to this position. The guide element 10, shown in Fig. 1 to 4 is provided with a fastening part 11, by which it is fastened to a slay or to an intermediate profile in a row with the identical guide elements. Above the fastening part 11 is the portion 12 of the guide element, which is meant to penetrate into a weav- ing shed. In this portion 12 the guide element has guides 14, 15, 16, 17 and 18, positively enclosing a gripper transport element 19 (Fig. 3 and 4) or surrounding it, so that all the guides 14, 15, 16, 17, 18 are termed as a frame 13 for the gripper transport element 19. The frame 13 is open at one side, i.e. the side facing the reed (not shown). The guide 14 is asso- ciated to the lower side of the gripper transport element 19. The guide 15 guides the gripper transport element 19 on the side facing away from the open side, i.e. against the movements away from the open side. The guide 16 is associated to the upper side of the gripper transport element 19 and prevents movement of the gripper transport element 19 in upward direction. The guides 17 and 18 are lateral edges of the projec- tions 40, 41, which project from the guide 16, associated to the upper side or from the guide 14, associated to the lower side and leave a gap in between. The guide 18 essentially runs parallel to the guide 15. The guide 17 extends by an angle of about 45° to the guide 16. The upper edge of the gripper transport element 19 is inclined in shape, in the area at the open side of the frame 13. The gripper transport element 19 is in this manner advantageously guided in all directions by the guide ele- ments 10. From the lower projection 41 of the guide element 10, a shoulder 20 pro- trudes outwards from the frame 13, whose upper edge 43 lies as high as the guide 14 that is associated to the lower side of the gripper transport element 19. The upper edge 43 lies deeper than the upper edge 42 of the projection 41. The gripper transport element 19 has an enlargement 21 (Fig. 4) extending at least over a part of its length with a length of, e.g. 500 mm, which remains outside the frame 13 and is used to accommodate a gripper. The gripper transport element 19 can be a gripper band, which is relatively flexible about a horizontal axis, or a gripper rod that is rela- tively rigid to bending about a horizontal axis as well as about a vertical axis. The enlargement 21 can be formed on the gripper transport element 19 as a single piece. In a modified embodiment, it is provided that, to the gripper transport element 19, a guiding part is attached, which completes and/or replaces the gripper transport element 19 over a part of its length and which features the enlargement 21 and carries the gripper. The shoul- der 20, with its upper edge 43 serving as a guide, supports the lower side of the gripper transport element in the area of the enlargement 21, so that torsional forces can be compensated. The guide element 10 in total has a somewhat plate-shaped form and is mounted on a slay such that the flat sides essentially run parallel to warp- threads. As seen in particular from Fig. 1 and 2, the portion 12 meant for penetrating into a shed of the guide element 10 is machined in such a manner that it tapers in the direction towards the open side towards the shoulder 20, which forms some kind of a pike. From this somewhat rounded pike of the shoulder 20, a lateral edge 22 runs in a manner of a rounded groove to the fastening part 11. The lateral edge 22 is chamfered and transforms into the flanks of the portion 12. Due to the tapering shape, the guide 15 is relatively wide and in this embodiment has a nearly uniform width. In a modified embodiment, the guide 15 has a trapezoidal shape. The guide 14 tapers in contrast, in the direction towards the open side and has approximately a trapezoidal shape. The same applies to the guides 16 and 17. The projection 41 with the guide 18 has a rounded upper edge 42 and chamfered side surfaces that taper upwards, which transform into the flanks of the portion 12. The portion 12 has an upper edge 23 that is rounded. The surfaces adjoining the upper edge 23 are chamfered so that they run up to the guides 16, 17 in an inclined manner with respect to the flanks of the portion 12. As can be seen from Fig. 3 and 4, the upper edge 23 has a highest point 24, which lies in the area of the open side of the frame 13. This highest point 24 is the point by which the guide element 10 first enters into a warp-thread sheet and thereby spreads the warp-threads apart. The warp-threads then slide on the inclined surfaces, which adjoin the upper edge 23. They are then already spread relatively widely apart when the projection 41 and the shoul- der 20 enter their area. Since the shoulder 20 lies under the upper edge 42 of the projection 41, and is preferably formed as a pike, it will penetrate be- tween the already spread warp-threads. As the projection 41 tapers up- wards and lies below the projection 40, it is shielded by the latter. The pro- jection 41 can therefore easily enter between the already spread warp- threads. As the shoulder 20 and in particular also its upper edge 43 lies lower than the projection 40, the shoulder 20 can therefore enter between the warp- threads already spread apart by the projection 41 and the projection 40, without damaging warp threads. The shoulder 20 is shielded by the projec- tions 40 and 41, so that it does not catch warp-threads, which run inclined to the rest of the warp-threads. Due to this, it is achieved that no warp- threads remain lying on the upper edge 43 of the shoulder 20, which could then be caught by the gripper transport element and be torn apart or be damaged. A particularly good spreading-apart of warp-threads is then achieved if the guide element 10 is made relatively wide in the area of the guide 15. As seen, in particular from Fig. 1 and 2, all edges of the thread guide ele- ments 10, which could contact the threads and/or the gripper transport ele- ment are rounded. Also the outer edge lying behind the guide 15, and facing away from the open side, is rounded and chamfered over a wide section. The embodiments according to Fig. 5 and 6 correspond in principle to the embodiment according to Fig. 1 to 4, whereby the guides are opposite one another in pairs and run perpendicular relative to one another in pairs. The guides 14, 16 guide the gripper transport element 19 against movement in vertical direction. The guides 15, 18 and 27 run parallel to one another and prevent movement of the gripper transport element 19 in horizontal direction. The gripper transport element 19 of Fig. 5 is provided with an enlargement 28, which is smaller in height than the height of the gripper transport ele- ment. In the embodiment according to Fig. 6, it is provided that, the portions forming the outer sides of the guides 18 and 27 also serve as guides 45, 46, which are opposite corresponding surfaces of the enlargement 29 of the gripper transport element 19. Due to this, good support is achieved against possible active torsional forces in the area of the enlargement 29. In a modified embodiment relative to Fig. 5 and 6, it is provided that the upper edge of the guide elements is designed such that it has the highest point in the area of the open-side similar to the highest point 24 of the embodiment ac- cording to Fig. 1 to 4, by which the guide elements first enter a warp sheet. The embodiment according to Fig. 7 to 10 in its basic design corresponds to the embodiment according to Fig. 1 to 4, so that reference is made to the de- scription of Fig. 1 to 4 and the same reference numbers are used. In the em- bodiment according to Fig. 7 to 10, it is additionally provided that from the guide 14 associated to the lower side of the gripper transport element 19 a projection 30 protrudes into the frame 13. This projection 30 forms additional side guides that prevent movement of the gripper transport element in hori- zontal direction and in particular in the direction towards the open side. Enlargement of the guides help to reduce abrasion. In the embodiment according to Fig. 11, which essentially corresponds with the embodiment according to Fig. 1 to 4, the upper edge 43 of the shoulder 20 is offset downwards relative to the guide 14. This further reduces the dan- ger that warp-threads have contact with the upper edge 43 of the shoulder 20, as the warp-threads are spread through the projection 41 and the adjoin- ing side surfaces of the guide element. The danger of damage to the warp- threads is the lower, the greater the distance between the upper edge 42 of the projections 41 and the upper edge 43 of the shoulder 20 is. The embodi- ment according to Fig. 12 differs from the embodiment according to Fig. 11, in that, a projection 30 is provided, which protrudes from the guide 14 and engages into a longitudinal groove of the gripper transport element 19. In the embodiment according to Fig. 13, which broadly corresponds to the embodiment according to Fig. 11, a distance or clearance is provided be- tween the upper edge 42 of the projection 41 and the groove root of the lon- gitudinal groove of the gripper transport element 19. Thus, it is avoided that the relatively narrow upper edge created in the area of the groove root of the longitudinal groove of the gripper transport element increases wear. In the example of the embodiment according to Fig. 13, a distance or clearance is provided between the lower side 44 of the projection 40 of the guide element 10 and the groove root of a longitudinal groove of the gripper transport ele- ment 19. The gripper transport element 19 according to Fig. 14 has a flat, rectangular cross section and is particularly suitable for use as a gripper band, which can be guided by means of a guide block around a drive wheel of a gripper weav- ing machine. The gripper transport element 19 is guided by means of a guide element 80 that has a guide 81 for the smooth upper side of the gripper trans- port element 19 that is not profiled by a groove or the like. The guide of the guide element 80 associated to the lower side of the gripper transport ele- ment is provided with a projection 41 that engages into a longitudinal groove of the gripper transport element 19. Also in this embodiment a shoulder 20 is provided, whose upper edge lies deeper than the upper edge of the projec- tion 41 and is thus shielded in the manner already described when entering into a warp sheet. The embodiment according to Fig. 15 differs from the embodiment according to Fig. 14 in that a second projection 30 protrudes from the guide 88 associ- ated to the lower side of the gripper transport element 19. The longitudinal grooves of the gripper transport element 19 and the projections 30, 41 are matched to one another such that clearance is provided between the upper edges of the projections 30, 41 and the groove root of the longitudinal grooves of the gripper transport element 19. As shown by means of Fig. 16, the upper edge 43 of the shoulder 20 must not be lower than the guide 88 in similarity to the exemplary embodiment ac- cording to Fig. 14 or 15. It is, however, essential that the upper edge 43 of the shoulder 20 is disposed lower than the upper edge 42 of the projection 41. In the embodiment according to Fig. 17, the projection 41 in the direction of the width of the gripper transport element 19 is kept relatively wide. The guide element 80 only forms guides with the upper edge of the projection 41 and the upper edge 43 of the shoulder 20, which prevent movement of the gripper transport element downwards. A clearance 84 is provided in the area facing away from the open side between the guide element 80 and the lower side of the gripper transport element 19. In Fig. 18 a modified embodiment of Fig. 17 is shown, with which the upper side of the gripper transport element 19 is provided with a longitudinal groove in which a projection 86 of the guide element 80 engages opposite the projec- tion 41. The gripper transport element 19 is guided in vertical direction only by the upper edge of the projection 41 and the lower edge of the projection 86. Clearance 85 is provided adjacent to the guide 87 between the upper side of the gripper transport element and the guide element 80. The guide elements formed according to Fig. 14 to 18 are particularly well suited to absorb torsional forces which may be introduced in the gripper transport element 19 due to the arrangement of a gripper (not shown) in par- ticular during accelerations and decelerations. Modified embodiments provide that the shoulder 20 facing away from the open side of the guide elements 10 or 80 is not designed as a tapered pike, but is provided with parallel surfaces. This design in particular is then possible if the guide elements 10, 80 in the area of the guides 15, 87 are relatively wide and therefore warp-threads are widely spread, when the upper edge 43 of the shoulder 20 reaches in the area of the warp-threads. The invention is not limited to the shown exemplary embodiments. Particu- larly, it is possible to implement the features described in the individual ex- emplary embodiments also with other exemplary embodiments. For instance, it is possible also with the exemplary embodiment according to Fig. 5 or 6, to provide a projection according to the projection 30. Likewise, it is possible with the embodiments according to Fig. 1 to 4 or 7 to 10 to use other gripper transport elements, in particular, gripper transport elements that are provided with enlargements 28 or 29 according to Fig. 5 and 6. With further modified embodiments, thus, in the area of the guide 16 associated to the upper side of the gripper transport element 19, one or several shoulders are provided, projecting into the frame 13 in accordance with the projection 30 of Fig. 7 and 10. WE CLAIM 1. A guide element (10, 80) for a gripper transport element (19), of a weaving machine, comprising guides (14, 15, 16, 17, 18, 42, 87), forming a positive frame (13) for the gripper transport element, open on one side, wherein the frame (13) is provided with at least one projection (41) associated to a longitudinal groove on the lower side of the gripper transport element (19), which protrudes from a guide (14) of the frame (13) associated to the lower side of the gripper transport element (19), that the frame (13) at the open side adjoining the projection is provided with a shoulder (20), characterized in that the shoulder (20) is designed in form of a pike directed away from the frame (13), and whose upper edge (43) forms a guide for the gripper transport element (19), which is located below the upper edge (42) of the projection (41), and in that a projection (40) protrudes from the guide (16) associated to the upper side of the gripper transport element, which faces the protruding projection (41) from the guide (14), associated to the lower side of the gripper transport element (19), wherein the projections (40,41) leave a gap in between. 2. A guide element as claimed in claim 1, wherein the upper edge (43) of the shoulder (20) serving as a guide runs as an elongation of a guide (14) associated to the lower side of the gripper transport element (19). 3. A guide element as claimed in one of claims 1 to 2, wherein below the shoulder (20) a rounded side edge is provided, which with chamfered surfaces transforms into the side flanks of the guide element (10). 4. A guide element as claimed in one of claims 1 to 3, wherein the guide element (10) in its portion (12) meant for entering into a weaving shed has a flat, plate-shaped design and that its thickness reduces in the direction towards the open side. 5. A guide element as claimed in one of claims 1 to 4, wherein the guide element has a rounded upper edge (23). 6. A guide element as claimed in claim 5, wherein the upper edge (23) of the guide element (10) has a highest point (24), which is located in the area above the open side of the frame (13). 7. A guide element as claimed in one of claims 1 to 6, wherein the upper edge (23) in the area of the highest point (24) encloses an obtuse angle. 8. A guide element as claimed in one of claims 1 to 7, wherein the section of the upper edge running from the highest point (24) of the upper edge (23) to the open side of the frame (13) runs with an angle of about 45° to the guide surface of the opposite guide section. 9. A guide element as claimed in one of claims 1 to 8, wherein the frame (13) has a guide (17), which runs at least approximately parallel to the inclined section of the upper edge (23), which extends from the highest point (24) towards the open side. 10. A guide element as claimed in one of claims 1 to 9, wherein the lower projection (41) limiting the gap with chamfered surfaces transforms into the side flanks of the guide elements. 11. A guide element as claimed in one of the claims 1 to 10, wherein from the guide (14, 16) associated to the lower side and/or the upper side of the gripper transport element (19) a projection (30) protrudes into the frame (13), whose side surfaces are additional guides. 12. A guide element as claimed in one of claims 1 to 11, wherein the upper edge (43) of the shoulder (20) is displaced downwards with respect to a guide (14) associated to the lower side of the gripper transport element (19). ABSTRACT "GUIDE ELEMENT FOR A GRIPPER TRANSPORT ELEMENT OF A WEAVING MACHINE" The invention relates to a guide element (10, 80) for a gripper transport element (19), of a weaving machine, comprising guides (14, 15, 16, 17, 18, 42, 87), forming a positive frame (13) for the gripper transport element, open on one side, wherein the frame (13) is provided with at least one projection (41) associated to a longitudinal groove on the lower side of the gripper transport element (19), which protrudes from a guide (14) of the frame (13) associated to the lower side of the gripper transport element (19), that the frame (13) at the open side adjoining the projection is provided with a shoulder (20), characterized in that the shoulder (20) is designed in form of a pike directed away from the frame (13), and whose upper edge (43) forms a guide for the gripper transport element (19), which is located below the upper edge (42) of the projection (41), and in that a projection (40) protrudes from the guide (16) associated to the upper side of the gripper transport element, which faces the protruding projection (41) from the guide (14), associated to the lower side of the gripper transport element (19), wherein the projections (40,41) leave a gap in between.

Full Text

Description
Guide element for a gripper transport element of a weaving machine
The invention relates to a guide element for a gripper transport element of
a weaving machine with guides that form a form-closed frame that is open
on one side for the gripper transport element.
Gripper transport elements consist of gripper rods or gripper bands that are
introduced into a weaving shed from one side of the weaving machine. A
gripper transport element moves a gripper, that has taken up a weft thread,
either to the opposite side of the weaving shed, where the weft thread is
taken over by a takeover element. Or the gripper transport element moves
with the gripper and the weft thread to the middle area of the weaving
shed, where it is likewise approached by a takeover gripper on a gripper
transport element that takes over the inserted weft thread and then trans-
ports the weft thread to the other side of the shed in a motion out of the
weaving shed. Or the gripper transport element moves with a gripper, a
take-over gripper, through the weaving shed and catches a weft thread that
is then pulled through the shed. The gripper transport elements are guided
within the shed by means of guide elements that are fixed on the slay.
They move with the slay, whereby they penetrate into a warp-thread sheet
from below, when the reed is moved away from the fell line of the cloth.
They again move out of the shed through the lower warp-thread sheet,
when the newly inserted weft thread is beaten up by the reed at the fell line
of the cloth.
Hook-shaped guide elements are known (EP 02 75 479 B1), whose open
side faces the reed. They serve particularly for guiding a gripper transport
element designed as a gripper band. They have a guide associated to the
upper side of the gripper transport element and a guide associated to the

opposite lower side of the gripper transport element. A further guide is pro-
vided for a side surface of the gripper transport band, on the side facing
away from the open side. The lower and/or upper guide engage in a longi-
tudinal groove of the lower side and/or the upper side of the gripper band,
whereby the sides of the guides, facing away from the open side, secure
the gripper band against movement towards the open side. The guides for
preventing the movement of the gripper band in the direction towards the
open side are relatively small. This causes substantial abrasion on the
guide elements and on the gripper transport elements in a relatively short
time.
C-shaped guide elements are also known (WO 94/10364), which are like-
wise open towards the reed. The gripper transport element that in this
case can also be a flexible gripper band is guided on the open side of the
guide element by means of two opposite portions of guides, which prevent
movement in the horizontal direction towards the reed. The upper side
and the lower side of the gripper transport element keep a distance from
the opposite portions of the guide elements, so that they are not guided.
The gripper transport element has a section extending through the open
side of the guide elements, which is guided in vertical direction between
the opposite portions of the guides. Also with this type, in particular in the
direction towards the reed, only relatively small guides are provided, so
that rapid abrasion is expected.
Further guides are known (EP 07 15 009 Al), which support a gripper band
only on the lower side and thereby engage in a longitudinal groove of the
lower side of the gripper band. The gripper band and the gripper are se-
cured against lifting only by means of gravity. It is expected that such
guide elements are not adequate in case of very high weaving speeds,
since the gripper bands lift and/or are prone to kinking.

The invention has the object to provide guide elements of the type men-
tioned at the beginning, which improve the guidance of the gripper transport
elements.
This object is achieved in that, the frame is provided with at least a projection
associated to a longitudinal groove of the lower side of the gripper transport
element, and a shoulder adjoining the projection on the open side, whose
upper edge forms a guide for the gripper transport element located below
the upper edge of the projection.
Since the frame encloses the gripper transport element with the guides that
are associated to the upper side and to the lower side of the gripper trans-
port element, relatively large guides are obtained without the dimensions
having to be increased. It is even possible to reduce the size of the cross-
sections of the gripper transport elements without having to reduce the size
of the guides and guide surfaces. Smaller cross-sections lead to smaller
masses and therefore allow higher weaving speeds. Particularly advanta-
geous is the shoulder which projects from the frame to the open side. This
shoulder on the one hand forms a support for a part of the gripper transport
element located outside the frame so that the transport element can be sup-
ported against torsional forces. Furthermore, the shoulder reduces the dan-
ger that warp-threads get caught in the guide elements, which could lead to
damage of the warp-threads and/or to warp-thread breaks.
According to an advantageous embodiment of the invention, it is provided
that, the shoulder is designed as a pike protruding away from the frame.
This pike can be inserted between two warp-threads that have already been
pushed apart by the upper edge of the guide elements.
In a further embodiment of the invention, it is provided that, the upper
edge of the guide element has a highest point that is located in the area

above the open side of the frame. The upper edge of the guide elements
first meets the warp-thread sheet and presses the warp-threads some-
what apart. The shoulder lies in the "shadow" of the upper edge, so that
it easily penetrates between the warp-threads that are already pushed
apart. The danger that warp-threads will be caught is therefore signifi-
cantly reduced. Likewise, the danger that warp-threads may contact the
guides for the gripper transport element is reduced.
Further features and advantages of the invention will become apparent
from the following description of the embodiments illustrated in the accompanying draw-
ings and in the dependent claims.
Fig. 1 shows a perspective view of a guide element according to
the invention,
Fig. 2 shows a perspective view of the guide element according
to Fig. 1 from the other side,
Fig. 3 shows a schematic side view of the guide element according
to Fig. 1 and 2 together with a gripper transport element
guided therein,
Fig. 4 shows a view of the guide element according to Fig. 1 to 3
with a gripper transport element at a different cross-section,
Fig. 5 shows a schematic view of a further embodiment of a guide
element with a gripper transport element in cross-section,
Fig. 6 shows the guide element according to Fig. 5 with a modi-
fied gripper transport element,

Fig. 7 shows a perspective view on a further embodiment of a
guide element,
Fig. 8 shows a perspective view of the guide element of Fig. 7
from the opposite side,
Fig. 9 shows a schematic view of the guide element according to
Fig. 7 and 8 together with a gripper transport element in
cross-section,
Fig. 10 shows the view of the guide element according to Fig. 7 to9
with a gripper transport element at a different cross-section
and
Fig. 11 to 18 shows further embodiments of guide elements according to
the invention.
The guide elements shown in Fig. 1 to 18, like shown in EP 0576854 A1,
are fixed on a slay that accommodates a reed as well. The slay executes
to-and-from movements in order to beat up a weft thread at the cloth fell.
Thereby, the guide elements are brought through the lower warp-thread
sheet in a weaving shed, when the reed is in the rear position and a weft
thread is inserted. To beat up the weft thread, the slay with the reed
moves towards the cloth fell, whereby the guide elements, after the gripper
transport element has been pulled back, again moves through the lower
warp sheet out of the shed. In the drawings, only the position is shown in
which the reed is located in the farthest position it moved back to and in
which a gripper transport element is inserted into a shed. When the terms
"upper" and "lower" are used, then they respectively refer to this position.

The guide element 10, shown in Fig. 1 to 4 is provided with a fastening
part 11, by which it is fastened to a slay or to an intermediate profile in a
row with the identical guide elements. Above the fastening part 11 is the
portion 12 of the guide element, which is meant to penetrate into a weav-
ing shed. In this portion 12 the guide element has guides 14, 15, 16, 17
and 18, positively enclosing a gripper transport element 19 (Fig. 3 and 4)
or surrounding it, so that all the guides 14, 15, 16, 17, 18 are termed as a
frame 13 for the gripper transport element 19. The frame 13 is open at
one side, i.e. the side facing the reed (not shown). The guide 14 is asso-
ciated to the lower side of the gripper transport element 19.
The guide 15 guides the gripper transport element 19 on the side facing
away from the open side, i.e. against the movements away from the open
side. The guide 16 is associated to the upper side of the gripper transport
element 19 and prevents movement of the gripper transport element 19 in
upward direction. The guides 17 and 18 are lateral edges of the projec-
tions 40, 41, which project from the guide 16, associated to the upper
side or from the guide 14, associated to the lower side and leave a gap in
between. The guide 18 essentially runs parallel to the guide 15. The
guide 17 extends by an angle of about 45° to the guide 16. The upper
edge of the gripper transport element 19 is inclined in shape, in the area
at the open side of the frame 13. The gripper transport element 19 is in
this manner advantageously guided in all directions by the guide ele-
ments 10.
From the lower projection 41 of the guide element 10, a shoulder 20 pro-
trudes outwards from the frame 13, whose upper edge 43 lies as high as
the guide 14 that is associated to the lower side of the gripper transport
element 19. The upper edge 43 lies deeper than the upper edge 42 of the
projection 41. The gripper transport element 19 has an enlargement 21
(Fig. 4) extending at least over a part of its length with a length of, e.g.

500 mm, which remains outside the frame 13 and is used to accommodate
a gripper. The gripper transport element 19 can be a gripper band, which
is relatively flexible about a horizontal axis, or a gripper rod that is rela-
tively rigid to bending about a horizontal axis as well as about a vertical
axis. The enlargement 21 can be formed on the gripper transport element
19 as a single piece. In a modified embodiment, it is provided that, to the
gripper transport element 19, a guiding part is attached, which completes
and/or replaces the gripper transport element 19 over a part of its length
and which features the enlargement 21 and carries the gripper. The shoul-
der 20, with its upper edge 43 serving as a guide, supports the lower side
of the gripper transport element in the area of the enlargement 21, so that
torsional forces can be compensated.
The guide element 10 in total has a somewhat plate-shaped form and is
mounted on a slay such that the flat sides essentially run parallel to warp-
threads. As seen in particular from Fig. 1 and 2, the portion 12 meant for
penetrating into a shed of the guide element 10 is machined in such a
manner that it tapers in the direction towards the open side towards the
shoulder 20, which forms some kind of a pike. From this somewhat rounded
pike of the shoulder 20, a lateral edge 22 runs in a manner of a rounded
groove to the fastening part 11. The lateral edge 22 is chamfered and
transforms into the flanks of the portion 12. Due to the tapering shape, the
guide 15 is relatively wide and in this embodiment has a nearly uniform
width. In a modified embodiment, the guide 15 has a trapezoidal shape.
The guide 14 tapers in contrast, in the direction towards the open side and
has approximately a trapezoidal shape. The same applies to the guides 16
and 17. The projection 41 with the guide 18 has a rounded upper edge 42
and chamfered side surfaces that taper upwards, which transform into the
flanks of the portion 12. The portion 12 has an upper edge 23 that is
rounded. The surfaces adjoining the upper edge 23 are chamfered so that

they run up to the guides 16, 17 in an inclined manner with respect to the
flanks of the portion 12.
As can be seen from Fig. 3 and 4, the upper edge 23 has a highest point 24,
which lies in the area of the open side of the frame 13. This highest point 24
is the point by which the guide element 10 first enters into a warp-thread
sheet and thereby spreads the warp-threads apart. The warp-threads then
slide on the inclined surfaces, which adjoin the upper edge 23. They are then
already spread relatively widely apart when the projection 41 and the shoul-
der 20 enter their area. Since the shoulder 20 lies under the upper edge 42
of the projection 41, and is preferably formed as a pike, it will penetrate be-
tween the already spread warp-threads. As the projection 41 tapers up-
wards and lies below the projection 40, it is shielded by the latter. The pro-
jection 41 can therefore easily enter between the already spread warp-
threads.
As the shoulder 20 and in particular also its upper edge 43 lies lower than
the projection 40, the shoulder 20 can therefore enter between the warp-
threads already spread apart by the projection 41 and the projection 40,
without damaging warp threads. The shoulder 20 is shielded by the projec-
tions 40 and 41, so that it does not catch warp-threads, which run inclined
to the rest of the warp-threads. Due to this, it is achieved that no warp-
threads remain lying on the upper edge 43 of the shoulder 20, which could
then be caught by the gripper transport element and be torn apart or be
damaged. A particularly good spreading-apart of warp-threads is then
achieved if the guide element 10 is made relatively wide in the area of the
guide 15.
As seen, in particular from Fig. 1 and 2, all edges of the thread guide ele-
ments 10, which could contact the threads and/or the gripper transport ele-

ment are rounded. Also the outer edge lying behind the guide 15, and facing
away from the open side, is rounded and chamfered over a wide section.
The embodiments according to Fig. 5 and 6 correspond in principle to the
embodiment according to Fig. 1 to 4, whereby the guides are opposite one
another in pairs and run perpendicular relative to one another in pairs. The
guides 14, 16 guide the gripper transport element 19 against movement in
vertical direction. The guides 15, 18 and 27 run parallel to one another and
prevent movement of the gripper transport element 19 in horizontal direction.
The gripper transport element 19 of Fig. 5 is provided with an enlargement
28, which is smaller in height than the height of the gripper transport ele-
ment. In the embodiment according to Fig. 6, it is provided that, the portions
forming the outer sides of the guides 18 and 27 also serve as guides 45, 46,
which are opposite corresponding surfaces of the enlargement 29 of the
gripper transport element 19. Due to this, good support is achieved against
possible active torsional forces in the area of the enlargement 29.
In a modified embodiment relative to Fig. 5 and 6, it is provided that the upper
edge of the guide elements is designed such that it has the highest point in the
area of the open-side similar to the highest point 24 of the embodiment ac-
cording to Fig. 1 to 4, by which the guide elements first enter a warp sheet.
The embodiment according to Fig. 7 to 10 in its basic design corresponds to
the embodiment according to Fig. 1 to 4, so that reference is made to the de-
scription of Fig. 1 to 4 and the same reference numbers are used. In the em-
bodiment according to Fig. 7 to 10, it is additionally provided that from the
guide 14 associated to the lower side of the gripper transport element 19 a
projection 30 protrudes into the frame 13. This projection 30 forms additional
side guides that prevent movement of the gripper transport element in hori-

zontal direction and in particular in the direction towards the open side.
Enlargement of the guides help to reduce abrasion.
In the embodiment according to Fig. 11, which essentially corresponds with
the embodiment according to Fig. 1 to 4, the upper edge 43 of the shoulder
20 is offset downwards relative to the guide 14. This further reduces the dan-
ger that warp-threads have contact with the upper edge 43 of the shoulder
20, as the warp-threads are spread through the projection 41 and the adjoin-
ing side surfaces of the guide element. The danger of damage to the warp-
threads is the lower, the greater the distance between the upper edge 42 of
the projections 41 and the upper edge 43 of the shoulder 20 is. The embodi-
ment according to Fig. 12 differs from the embodiment according to Fig. 11,
in that, a projection 30 is provided, which protrudes from the guide 14 and
engages into a longitudinal groove of the gripper transport element 19.
In the embodiment according to Fig. 13, which broadly corresponds to the
embodiment according to Fig. 11, a distance or clearance is provided be-
tween the upper edge 42 of the projection 41 and the groove root of the lon-
gitudinal groove of the gripper transport element 19. Thus, it is avoided that
the relatively narrow upper edge created in the area of the groove root of the
longitudinal groove of the gripper transport element increases wear. In the
example of the embodiment according to Fig. 13, a distance or clearance is
provided between the lower side 44 of the projection 40 of the guide element
10 and the groove root of a longitudinal groove of the gripper transport ele-
ment 19.
The gripper transport element 19 according to Fig. 14 has a flat, rectangular
cross section and is particularly suitable for use as a gripper band, which can
be guided by means of a guide block around a drive wheel of a gripper weav-
ing machine. The gripper transport element 19 is guided by means of a guide
element 80 that has a guide 81 for the smooth upper side of the gripper trans-

port element 19 that is not profiled by a groove or the like. The guide of the
guide element 80 associated to the lower side of the gripper transport ele-
ment is provided with a projection 41 that engages into a longitudinal groove
of the gripper transport element 19. Also in this embodiment a shoulder 20 is
provided, whose upper edge lies deeper than the upper edge of the projec-
tion 41 and is thus shielded in the manner already described when entering
into a warp sheet.
The embodiment according to Fig. 15 differs from the embodiment according
to Fig. 14 in that a second projection 30 protrudes from the guide 88 associ-
ated to the lower side of the gripper transport element 19. The longitudinal
grooves of the gripper transport element 19 and the projections 30, 41 are
matched to one another such that clearance is provided between the upper
edges of the projections 30, 41 and the groove root of the longitudinal
grooves of the gripper transport element 19.
As shown by means of Fig. 16, the upper edge 43 of the shoulder 20 must
not be lower than the guide 88 in similarity to the exemplary embodiment ac-
cording to Fig. 14 or 15. It is, however, essential that the upper edge 43 of
the shoulder 20 is disposed lower than the upper edge 42 of the projection
41.
In the embodiment according to Fig. 17, the projection 41 in the direction of
the width of the gripper transport element 19 is kept relatively wide. The guide
element 80 only forms guides with the upper edge of the projection 41 and
the upper edge 43 of the shoulder 20, which prevent movement of the gripper
transport element downwards. A clearance 84 is provided in the area facing
away from the open side between the guide element 80 and the lower side of
the gripper transport element 19.

In Fig. 18 a modified embodiment of Fig. 17 is shown, with which the upper
side of the gripper transport element 19 is provided with a longitudinal groove
in which a projection 86 of the guide element 80 engages opposite the projec-
tion 41. The gripper transport element 19 is guided in vertical direction only
by the upper edge of the projection 41 and the lower edge of the projection
86. Clearance 85 is provided adjacent to the guide 87 between the upper
side of the gripper transport element and the guide element 80.
The guide elements formed according to Fig. 14 to 18 are particularly well
suited to absorb torsional forces which may be introduced in the gripper
transport element 19 due to the arrangement of a gripper (not shown) in par-
ticular during accelerations and decelerations.
Modified embodiments provide that the shoulder 20 facing away from the open
side of the guide elements 10 or 80 is not designed as a tapered pike, but is
provided with parallel surfaces. This design in particular is then possible if the
guide elements 10, 80 in the area of the guides 15, 87 are relatively wide and
therefore warp-threads are widely spread, when the upper edge 43 of the
shoulder 20 reaches in the area of the warp-threads.
The invention is not limited to the shown exemplary embodiments. Particu-
larly, it is possible to implement the features described in the individual ex-
emplary embodiments also with other exemplary embodiments. For instance,
it is possible also with the exemplary embodiment according to Fig. 5 or 6, to
provide a projection according to the projection 30. Likewise, it is possible with
the embodiments according to Fig. 1 to 4 or 7 to 10 to use other gripper
transport elements, in particular, gripper transport elements that are provided
with enlargements 28 or 29 according to Fig. 5 and 6. With further modified
embodiments, thus, in the area of the guide 16 associated to the upper side
of the gripper transport element 19, one or several shoulders are provided,

projecting into the frame 13 in accordance with the projection 30 of Fig. 7
and 10.

WE CLAIM
1. A guide element (10, 80) for a gripper transport element (19), of a
weaving machine, comprising guides (14, 15, 16, 17, 18, 42, 87),
forming a positive frame (13) for the gripper transport element, open on
one side, wherein the frame (13) is provided with at least one projection
(41) associated to a longitudinal groove on the lower side of the gripper
transport element (19), which protrudes from a guide (14) of the frame
(13) associated to the lower side of the gripper transport element (19),
that the frame (13) at the open side adjoining the projection is provided
with a shoulder (20), characterized in that the shoulder (20) is designed in
form of a pike directed away from the frame (13), and whose upper edge
(43) forms a guide for the gripper transport element (19), which is
located below the upper edge (42) of the projection (41), and in that a
projection (40) protrudes from the guide (16) associated to the upper side
of the gripper transport element, which faces the protruding projection
(41) from the guide (14), associated to the lower side of the gripper
transport element (19), wherein the projections (40,41) leave a gap in
between.
2. A guide element as claimed in claim 1, wherein the upper edge (43) of
the shoulder (20) serving as a guide runs as an elongation of a guide (14)
associated to the lower side of the gripper transport element (19).
3. A guide element as claimed in one of claims 1 to 2, wherein below the
shoulder (20) a rounded side edge is provided, which with chamfered
surfaces transforms into the side flanks of the guide element (10).

4. A guide element as claimed in one of claims 1 to 3, wherein the guide
element (10) in its portion (12) meant for entering into a weaving shed
has a flat, plate-shaped design and that its thickness reduces in the
direction towards the open side.
5. A guide element as claimed in one of claims 1 to 4, wherein the guide
element has a rounded upper edge (23).
6. A guide element as claimed in claim 5, wherein the upper edge (23) of
the guide element (10) has a highest point (24), which is located in the
area above the open side of the frame (13).
7. A guide element as claimed in one of claims 1 to 6, wherein the upper
edge (23) in the area of the highest point (24) encloses an obtuse angle.
8. A guide element as claimed in one of claims 1 to 7, wherein the section of
the upper edge running from the highest point (24) of the upper edge
(23) to the open side of the frame (13) runs with an angle of about 45° to
the guide surface of the opposite guide section.
9. A guide element as claimed in one of claims 1 to 8, wherein the frame
(13) has a guide (17), which runs at least approximately parallel to the
inclined section of the upper edge (23), which extends from the highest
point (24) towards the open side.

10. A guide element as claimed in one of claims 1 to 9, wherein the lower
projection (41) limiting the gap with chamfered surfaces transforms into
the side flanks of the guide elements.
11. A guide element as claimed in one of the claims 1 to 10, wherein from the
guide (14, 16) associated to the lower side and/or the upper side of the
gripper transport element (19) a projection (30) protrudes into the frame
(13), whose side surfaces are additional guides.
12. A guide element as claimed in one of claims 1 to 11, wherein the upper
edge (43) of the shoulder (20) is displaced downwards with respect to a
guide (14) associated to the lower side of the gripper transport element
(19).

ABSTRACT

"GUIDE ELEMENT FOR A GRIPPER TRANSPORT ELEMENT OF A
WEAVING MACHINE"
The invention relates to a guide element (10, 80) for a gripper transport element
(19), of a weaving machine, comprising guides (14, 15, 16, 17, 18, 42, 87),
forming a positive frame (13) for the gripper transport element, open on one
side, wherein the frame (13) is provided with at least one projection (41)
associated to a longitudinal groove on the lower side of the gripper transport
element (19), which protrudes from a guide (14) of the frame (13) associated to
the lower side of the gripper transport element (19), that the frame (13) at the
open side adjoining the projection is provided with a shoulder (20), characterized
in that the shoulder (20) is designed in form of a pike directed away from the
frame (13), and whose upper edge (43) forms a guide for the gripper transport
element (19), which is located below the upper edge (42) of the projection (41),
and in that a projection (40) protrudes from the guide (16) associated to the
upper side of the gripper transport element, which faces the protruding
projection (41) from the guide (14), associated to the lower side of the gripper
transport element (19), wherein the projections (40,41) leave a gap in between.

GUIDE ELEMENT FOR A GRIPPER TRANSPSORT ELEMENT OF A WEAVING MACHINE

Documents:

Inventors:

PCT Conventions: