Heald Frame for a Weaving Loom

The present invention relates to a heald frame for a weaving loom, in particular a weaving loom wherein weft insertion is achieved using a pressurized fluid, conveniently compressed air.

According to one aspect of the present invention there is provided a heald frame for a weaving loom comprising an upper cross-member and a lower cross-member adapted to support healds directly therebetween, said upper and lower cross-members being joined together by spaced end members, a plurality of connection members spaced along the length of the cross-members between the end members and attached to the cross-members to restrain relative movement between the cross-members and retain a constant spaced relationship between the cross-members along their length, said connection members having portions of a narrow width extending between the upper and lower cross-members so that, during weaving, warp yarns pass the connection members without interference, and first and second connection means disposed, respectively, at opposite ends of each connecting member for connection to means for causing reciprocation of the frame.

According to another aspect of the present invention there is provided a weaving loom including a plurality of heald frames, each heald frame comprising an upper cross-member and a lower cross-member, the upper and lower cross-members being connected together by spaced end members, a plurality of healds supported directly between the cross members, a plurality of connection members spaced along the length of the cross-members intermediate the end members and attached to both cross-members so as to have portions extending therebetween to restrain relative movement between the cross-members and thereby retain a constant spaced relationship between the cross-members along their length, the portions of the connection members extending between the upper and lower cross-members being of a narrow width to enable warp yarns to pass through the heald frame without interference, first and second connection means disposed, respectively, at opposite ends of each connecting member, a first motive means for moving the frame in one direction, the first motive means for moving the frame in one direction, the first motive means being connected to each of said first connection means by a first suspension means, and a second motive means for moving the frame in the opposite direction, the second motive means being connected to each of said second connection means by a second suspension means.

Reference is now made to the accompanying drawings, in which:

FIG. 1 shows a partly broken away perspective view of a part of a loom according to the present invention as viewed from the front and one end of the loom;

FIG. 2 is a part perspective view of a heald frame according to the present invention; and

FIG. 3 is a more detailed part perspective view of the heald frame shown in FIG. 2.

The loom 10 has a main frame which includes a pair of end walls 14 which are spaced apart and connected to one another by an upper cross-member 51 and a lower cross-member 17 (FIG. 2). The end walls 14 are preferably formed from steel plate.

The end walls 14 have rearwardly extending portions 14a which serve to rotatably support a beam 18 on which is wound the warp threads 20.

The warp threads 20 pass through a plurality of heald frames 80 shown schematically in FIG. 1. The heald frames 80 are each supported from an overhead frame 51 by means of cables 82 which extend via rollers 54 and 55 and a series of rollers 56 to a series of cam followers 57 which are operated by a series of cams 59 mounted on a cam shaft 60. The rollers 56 are laterally offset from one another to each co-operate with the cables extending from successive groups of cam followers. The cam shaft 60 is driven from a stub shaft via a chain 71. The stub shaft forms part of a clutch assembly 72.

Each heald frame 80 is biased downwardly by means of coiled springs 188 attached at one end to the heald frame and at the other end to the lower cross-member 17. The cam follower for each heald frame is thereby maintained in contact with a respective cam. Wicks 76 are provided which contact the cams to lubricate them with oil from an oil bath 77.

The heald frame 80 of the present invention is more clearly illustrated in FIGS. 2 and 3. The heald frame 80 is designed so as to be lighter in construction than conventional heald frames thereby enabling higher speeds of weaving to be achieved.

The frame 80 includes upper and lower cross-members 81a, 81b respectively which extend across the width of the loom and are secured to one another at their ends by end members 81c. In the usual manner, a plurality of healds 81d (only one of which is shown in FIG. 3) are connected to the cross-members 81a, 81b. Each cross-member 81a, 81b is preferably formed from a thin metal strip.

The frame 80 is suspended from cables 82 which are located at spaced intervals across the width of the loom. Each cable is connected to an upper suspension member 83 which at its lower end has a hook formation 84. A connection member 85 is suspended from each hook formation 84 by means of an aperture 187 formed in the upper portion of said member and serves as a connection between the heald frame 80 and suspension member 83. Each connection member 85 extends between cross-members 81a, 81b to connect them together and retain them in spaced relationship. Each connection member 85 has upper and lower recesses 86a, 86b which respectively house the upper and lower cross-members 81a, 81b. Each recess 86a, 86b, has a mouth portion 87 which in length is less than the width of cross-members 81a, 81b so as to define a shoulder 88 which prevents member 81a or 81b moving out of a respective recess in which it is housed.

In order to enable a cross-member 81a, 81b to be inserted into a respective recess 86a, 86b a slot 89 is provided which enables the side edges of the cross-member 81a or 81b to be deflected inwardly so that they may pass through the mouth portion 87. In order to positively locate connection members 85 at predetermined intervals along the length of members 81a, 81b, location projections 181 are provided which project from the base of each recess 86a, 86b and which are received in a transverse slot 182 formed in a respective cross-member 81a or 81b.

As seen in the drawings, connection members 85 are also formed from a strip material, preferably a metal strip, and are arranged so that their flat sides are located substantially perpendicularly to the flat sides of cross-members 81a, 81b. This affords two advantages, viz. (a) the connection members 85 add rigidity to frame 80 by rigidly holding cross-members 81a, 81b at a predetermined spacing and by restraining laterial bending and (b) the connection members 85 present their narrow edges to the warp sheet and thereby do not interfere with the warp yarns, i.e. the narrow width of the connection members 85 enables warp yarns to pass either side without excessive deflection.

A lower suspension member 185 is provided which has an upper hook formation 186 located in an aperture 187 formed in the lower portion of a connection member 85. Each suspension member 185 is connected to the lower cross-member 17 of the loom via a spring 188 which serve to bias the frame 80 downwardly.

Upper and lower suspension members 83 and 185 have substantially the same width between their respective transverse sides 189, 190, which sides are flat and serve to permit sliding abutment between adjacent suspension members associated with neighbouring heald frames 80. Conveniently, the overhead frame 51 is provided with a row of depending arms 151 which serve as flat abutment surfaces against which the upper suspension members 83 associated with the heald frame 80 may slidingly abut nearest to overhead frame 51. This arrangement tends to further restrain lateral bending of frames 80.

Each upper suspension member 83 preferably comprises a body 283 having a longitudinally extending slot 284 in which part of a cable clamp 285 is housed. The body 283 also includes a slot 282 which communicates with slot 284 and opens out at a side 286. The clamp 285 has a portion 285a which extends through slot 282 and has a pair of shoulders 285b (only one of which is visible) which slidingly abut against side 286. The upper portion 285c of clamp 285 slidingly abuts the base of slot 284. The clamp member 285 includes a bore for receiving the cable 82 to which is to be attached and is provided with several clamping screws 289 for engaging the cable. An adjusting screw 291 is threadingly received in the upper portion of the body 283 and projects into slot 282 to engage the portion 285a of the clamp member. Accordingly, by rotating screw 291 the clamp member 285 may be moved along slot 284 so as to provide accurate height adjustment of the suspension member 83. Conveniently, body 283 and the corresponding body of suspension member 185 are plastic mouldings.