EP0494127B1 - Spring assembly for dobbies and other negative weaving device - Google Patents

Description

The present invention relates to dobbies and other weaving mechanics of the negative type for the formation of the crowd on weaving machines, and it relates more particularly to the registers of springs which, in this kind of mechanics, ensure the recall of the frames of smooth operated with the latter.

It is known that indeed the negative type mechanics operate the positive control of the heald frames only in one direction of the alternative travel of the latter, so that it is necessary to provide elastic means arranged so to operate the recall of said frames at the other end of the race. These elastic means are most often constituted by two registers formed by parallel springs retained between two fastening clips, one of which is mounted on a fixed post on a console or rack integral with the structure of the loom, while the other is attached to the end of one of the cables provided for the operation of each frame.

It will be understood that the springs of each register are thus stretched during the positive control of the frame by the dobby or other mechanism (control which is most often performed by lowering), and, by elastic traction on the corresponding cable, bring back said frame in the initial position (high position in the case considered).

It should be observed here that the forces provided by the registers are very high, at least when these registers are associated with heald frames of large width for the operation of very stiff plies of warp son, so that the cables tend to twist under the load of the springs. However, any twisting effect of the cables causes contacting and mutual friction on the one hand of the movable clips of the packet of registers mounted side by side on the same side of all the frames, on the other hand and above all of the springs themselves. These untimely friction are the frequent cause of the rupture of the springs.

The document EU-A-0 325 547 (STAUBLI) cited in the Research Report suggests avoiding the risk of contact between the springs using intermediate elements or plates made integral with the fixed clip or rack in order to extend between the springs. However, it was only a question of prohibiting, in the particular case of a horizontally oriented register, the springs of the same register from colliding and this solution could not be structurally used to avoid contact between the springs of two adjacent registers of the same set of registers.

It is to this disadvantage that the present invention mainly intends to remedy, which relates to the spring register which is defined in claim 1.

It should be noted that the Search Report cites, in addition to the above-mentioned document, document EP-A-0 071 764 (GEBRUDER SCHMEING).

In fact, the invention essentially consists in having at the ends of the movable clip linked to the operating cable two lateral pads which are oriented parallel to the springs and whose thickness is slightly greater than the diameter of the latter so that the pads of the staples of two adjacent registers can rub against each other avoiding any contact between the springs attached to said staples .

• - Fig. 1 est une vue schématique en élévation montrant l'agencement d'un registre de ressorts établi conformément à l'invention.
• Fig. 2 illustre en perspective le montage de l'un des deux patins latéraux du registre suivant fig. 1.
• Fig. 3 représente, avec arrachement vertical, le guidage assuré par les patins de quatre registres contigus.
• Fig. 4 illustre une variante du mode de fixation des patins sur les agrafes.

The appended drawing, given by way of example, will allow a better understanding of the invention, the characteristics which it presents and the advantages which it is capable of providing:

• - Fig. 1 is a schematic elevational view showing the arrangement of a spring register established in accordance with the invention.
• Fig. 2 illustrates in perspective the mounting of one of the two lateral pads of the register according to FIG. 1.
• Fig. 3 shows, with vertical cutaway, the guidance provided by the pads of four contiguous registers.
• Fig. 4 illustrates a variant of the method of fixing the pads on the staples.

The register shown in 1 in fig. 1 comprises a series or ply of springs 2 hung vertically between two staples 3 and 4. The lower staple 3 of each register is fixed to a rack 5 secured to the vertical structure 6 of the weaving machine, while the upper staple 4, provided movable, is attached to a cable 7. The latter is linked at 8 a to a return lever 8 mounted to oscillate on an axis 9 carried by the structure 6, and it is laterally made integral with a heald frame 10 before hanging onto the corresponding movable member of a dobby or other mechanical of the negative type.

In accordance with the invention and as more particularly illustrated in FIG. 2 and 3, the upper clip 4 comprises at each of its ends, beyond the series of openings 4 is intended for the attachment of the folded end 2a of springs 2, a vertical back 4b pierced two superimposed holes 4 c . Each return 4b is adapted to be engaged vertically in the upper forked end 11a of a skate 11, the fixing in place of the latter being effected with the aid of two rivets 12 inserted into the holes 4c aforementioned and in corresponding holes 11 b formed in the forked end 11a of the pad 11 considered.

The pads 11 are made of a synthetic material promoting sliding and they are made at a thickness slightly greater than the diameter of the springs 2, so that as shown in FIG. 3, their lateral faces come into contact with the lateral faces of the pads of the contiguous registers 1.

It is therefore conceivable that the pads 11 of all of the registers 1 guide the movable staples 4 during the alternating vertical movements of the frames 10 of the loom, thereby opposing the effects of cable twisting and by in any event prohibiting any untimely friction of the springs 2 of two adjacent registers.

Tests have shown that the adoption of the pads 11 very significantly reduces the frequency of accidental ruptures of the springs 2 of the different registers 1 of a weaving machine.

The height presented by each shoe 11 can vary to a large extent, depending in particular on the amplitude of the stroke of the spring registers. It also goes without saying that any other method of fixing the pads 11 on the ends of the movable staples can be imagined, in particular that illustrated in FIG. 4 where it is assumed that the back 4 'b of the clip 4' was considered profiled so as to clip elastically inside a conjugate opening 11 'is provided in the upper end of each 11 'skate.

Claims (3)

1. Set of springs for dobbies and other weaving mechanisms of the negative type, comprising a series of springs (2) stretched between a fixed clip element (3) and a mobile clip element (4) attached to the end of a cable (7) for manoeuvring a heddle frame (10), characterized in that the ends of the mobile clip element (4) are equipped with blocks (11) which extend parallel to the springs (2) and whose thickness is slightly greater than the diameter of these latter in order that the conjugate lateral faces of the blocks of the clip elements of two contiguous sets rub against one another, preventing any untimely contact between the springs of said sets.
2. Set according to Claim 1, characterized in that, at the level of each of its ends, the mobile clip element (4) comprises a transverse return (4b) adapted to be engaged and fixed in the corresponding fork-shaped end (11a) of the conjugate block (11).
3. Set according to Claim 1, characterized in that each of the ends (4'b) of the mobile clip element (4') is sectioned to clip elastically inside a conjugate opening (11'a) provided in the corresponding end of the block (11').

Images