GB2147322A

GB2147322A - Rapier looms

Info

Publication number: GB2147322A
Application number: GB08422035A
Authority: GB
Inventors: Gunter Welzel; Ursula Orlowski; Karl-Heinz Hahn; Werner Hartmann
Original assignee: Kombinat Textima VEB
Current assignee: Kombinat Textima VEB
Priority date: 1983-09-27
Filing date: 1984-08-31
Publication date: 1985-05-09
Also published as: GB8422035D0; BE900514A; DE3428113A1; FR2552455A1; GB2147322B; CS253300B1; SU1418357A1; DD225863A3

Abstract

In a superposed shed rapier loom the gripper heads (2) of the weft thread picking element (1) for the upper and lower sheds are each provided with a guide component (3) having a recess (4) and a guide surface (5) and guide segments (8) are disposed on the sley bar (6) and sley cover (7) so that only the gripper head is guided. The guide segments entering the loom shed from above and below are provided with guide lugs (9) of which, in each case, at least two engage in the recess of the guide component. <IMAGE>

Description

SPECIFICATION Weft thread picking device The invention relates to a weft thread picking device on weaving machines for two superimposed fabric widths, wherein weft thread picking is effected by weft thread picking elements having gripper heads which are moved, in a positively connected manner, alternately into and out of the loom shed, which heads are rectilinearly guided by means of drives disposed rigidly on the frame and bearings disposed outside the loom shed.

Known thread picking devices are commonly guided in the loom shed during picking of the weft threads solely by the reed and by support on the warp threads or a sley path. The weft thread picking elements are in this respect, in the majority of cases, gripper rods or gripper bands. In the particular case of gripper bands it is also known to guide these in the loom shed over their entire length by additional guide elements. A device of this type is disclosed in the German Offenlegungsschrift 2 307 099 In this case the gripper band extends, during its movement, edgewise in a transverse manner over the sley and is supported by a plurality of guide fingers. The guide fingers are fastened to a hollow rail connected to the sley cover.

However, in the case of looms for double-width weaving at high speeds, it is not possible to use guides of the aforementioned type for the weft thread picking elements.

An object of the invention is to improve the efficiency of picking of the weft threads in weaving machines of the aforesaid type and thereby to improve the quality of the woven product.

In the weft thread picking device in accordance with the invention, guiding of the weft thread picking elements takes place within the loom shed solely at the gripper head. This is achieved in that the gripper head of each weft thread picking element for the upper shed and the lower shed is provided with a guide component comprising a groove-shaped recess and a guide surface and in that guide segments are so disposed on the sley bars and the sley cover that only the gripper head is guided in the loom shed during the picking of the weft threads.

The guide segments entering the loom shed from above and below are therefore directed with their guide lugs perpendicularly to the reed. During picking of the weft threads, at least two of the guide lugs of the guide segments are engaged in the recess of the guide component for the guiding of the gripper heads in the loom shed, and the guide surface of the guide component abuts the reed.

The guide segments of the upper and lower shed are conveniently disposed symmetrically to a perpendicular line in the plane of the reed.

The invention is exemplified in detail below with reference to an embodiment shown in the accompanying drawings, in which: Figure 1 is a side view of a weft thread picking device, illustrated in a simplified manner; Figure 2 is a top view of a section of a weft thread picking device having a gripper head and a guide component; and Figure 3 is a side view thereof.

Referring to the drawings, weft thread picking elements 1 are held in the longitudinal direction with sufficient stability to prevent deformation and bending and to support a gripper head 2. A guide component 3 is disposed on the gripper head 2, which component may be made of a suitable plastics material. The guide component 3 is provided on the one hand with a longitudinally extending, groove-shaped recess 4 and, on the other hand, with a guide surface 5. The weft thread picking elements 1 are conventionally mounted and driven outside the loom shed.

Figure 1 shows, for the sake of simplicity, solely the sley portion of a sley bar 6, the latter in the weft thread picking position. On the sley bar 6 and a sley cover 7, several groups of segments are distributed over the width of the sley, each group having ten guide segments 8 with guide lugs 9 orientated perpendicularly to a reed 10.

As can be seen from Figure 1, during picking of the weft threads, the guide surface 5 of the guide component 3 connected with the gripper head 2 lies on the reed 10, and the guide lugs 9 of the guide segments 8 engage in the groove-shaped recess 4 of the guide component 3. The mutual spacing of the guide segments 8 is maintained such that at least two guide lugs 9 are engaged in the recess 4 during the passage of the gripper heads 2.

The arrangement of the guide segments 8, the sley movement and the weft thread contact zones is selected such that their geometrical dimensions and their paths of movement are coordinated in order to ensure that, during sley contact, the guide segments 8 of the upper shed 11 pass above and the segments of the lower shed 12 pass below the weft contact zone and do not enter the direct weft contact zone. The guide segments 8 of the upper shed 11 and the lower shed 12 are disposed symmetrically about a perpendicular line in the plane of the reed.

1. A weft thread picking device in weaving machines for two superimposed fabric widths, wherein picking of the weft threads is effected by weft thread picking elements with gripper heads which are moved, in a positively connected manner, alternately into and out of the loom shed, which heads are rectilinearly guided by means of drives disposed rigidly on the frame and bearings disposed outside the loom shed, characterised in that the gripper heads of the weft thread picking elements for the upper shed and the lower shed are provided with a guide component having a recess and a guide surface and in that guide segments are so disposed on the sley bar and the sley cover that only the gripper head is guided in the respective loom shed.

2. A weft thread picking device as claimed in claim 1, characterised in that the guide segments

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Weft thread picking device The invention relates to a weft thread picking device on weaving machines for two superimposed fabric widths, wherein weft thread picking is effected by weft thread picking elements having gripper heads which are moved, in a positively connected manner, alternately into and out of the loom shed, which heads are rectilinearly guided by means of drives disposed rigidly on the frame and bearings disposed outside the loom shed. Known thread picking devices are commonly guided in the loom shed during picking of the weft threads solely by the reed and by support on the warp threads or a sley path. The weft thread picking elements are in this respect, in the majority of cases, gripper rods or gripper bands. In the particular case of gripper bands it is also known to guide these in the loom shed over their entire length by additional guide elements. A device of this type is disclosed in the German Offenlegungsschrift 2 307 099 In this case the gripper band extends, during its movement, edgewise in a transverse manner over the sley and is supported by a plurality of guide fingers. The guide fingers are fastened to a hollow rail connected to the sley cover. However, in the case of looms for double-width weaving at high speeds, it is not possible to use guides of the aforementioned type for the weft thread picking elements. An object of the invention is to improve the efficiency of picking of the weft threads in weaving machines of the aforesaid type and thereby to improve the quality of the woven product. In the weft thread picking device in accordance with the invention, guiding of the weft thread picking elements takes place within the loom shed solely at the gripper head. This is achieved in that the gripper head of each weft thread picking element for the upper shed and the lower shed is provided with a guide component comprising a groove-shaped recess and a guide surface and in that guide segments are so disposed on the sley bars and the sley cover that only the gripper head is guided in the loom shed during the picking of the weft threads. The guide segments entering the loom shed from above and below are therefore directed with their guide lugs perpendicularly to the reed. During picking of the weft threads, at least two of the guide lugs of the guide segments are engaged in the recess of the guide component for the guiding of the gripper heads in the loom shed, and the guide surface of the guide component abuts the reed. The guide segments of the upper and lower shed are conveniently disposed symmetrically to a perpendicular line in the plane of the reed. The invention is exemplified in detail below with reference to an embodiment shown in the accompanying drawings, in which: Figure 1 is a side view of a weft thread picking device, illustrated in a simplified manner; Figure 2 is a top view of a section of a weft thread picking device having a gripper head and a guide component; and Figure 3 is a side view thereof. Referring to the drawings, weft thread picking elements 1 are held in the longitudinal direction with sufficient stability to prevent deformation and bending and to support a gripper head 2. A guide component 3 is disposed on the gripper head 2, which component may be made of a suitable plastics material. The guide component 3 is provided on the one hand with a longitudinally extending, groove-shaped recess 4 and, on the other hand, with a guide surface 5. The weft thread picking elements 1 are conventionally mounted and driven outside the loom shed. Figure 1 shows, for the sake of simplicity, solely the sley portion of a sley bar 6, the latter in the weft thread picking position. On the sley bar 6 and a sley cover 7, several groups of segments are distributed over the width of the sley, each group having ten guide segments 8 with guide lugs 9 orientated perpendicularly to a reed 10. As can be seen from Figure 1, during picking of the weft threads, the guide surface 5 of the guide component 3 connected with the gripper head 2 lies on the reed 10, and the guide lugs 9 of the guide segments 8 engage in the groove-shaped recess 4 of the guide component 3. The mutual spacing of the guide segments 8 is maintained such that at least two guide lugs 9 are engaged in the recess 4 during the passage of the gripper heads 2. The arrangement of the guide segments 8, the sley movement and the weft thread contact zones is selected such that their geometrical dimensions and their paths of movement are coordinated in order to ensure that, during sley contact, the guide segments 8 of the upper shed 11 pass above and the segments of the lower shed 12 pass below the weft contact zone and do not enter the direct weft contact zone. The guide segments 8 of the upper shed 11 and the lower shed 12 are disposed symmetrically about a perpendicular line in the plane of the reed. CLAIMS

2. A weft thread picking device as claimed in claim 1, characterised in that the guide segments penetrating from above and below into the loom sheds have guide lugs orientated perpendicularly to the reed.

3. A weft thread picking device as claimed in claim 2, characterised in that, during picking of the weft threads, at least two guide lugs of the guide segments engage in each case in the recess of the guide component for the purpose of guiding the gripper heads in the loom sheds, and in that the guide surface abuts the reed.

4. A weft thread picking device as claimed in any one of claims 1 to 3, characterised in that the guide segments of the upper shed and the lower shed are disposed symmetrically to a perpendicular line in the plane of the reed.

5. A weft thread picking device in a weaving machine, substantially as hereinbefore described with reference to the accompanying drawings.