GB2083084A - Shaft arrangement on a loom, particularly a circular loom - Google Patents

Abstract

The heald shafts of a circular loom comprise upper rails (150) and lower rails (151), extending in each case between two adjacent rods (46) and pivotal thereon. Healds (52) are supported on the rails by plastics spacers (57). Shedding of the shafts permit a substantially uninterrupted undulatory movement of the eyelets (53) of healds (52). <IMAGE>

Description

SPECIFICATION Shaft arrangement on a loom, particularly a circular loom The present invention relates to a shaft arrangement of a loom, particularly a circular loom, in which in each case a plurality of inner and outer partial shafts are arranged in circular manner and in two rows around a main shaft ofthe loom and on whose shaft rods engage means for producing a shedforming lifting movement, propagating in undulatory manner over all the partial shafts, upper and lower rod-like pedal supports carrying the heddles being supported on the shaft rods.

In the prior art shaft arrangements of this type the partial shafts distributed in relatively large numbers and in uniform manner around the loom have in each case an associated shaft rod fixedly connected to both an upper and a lower heddle support. These heddle supports extend symmetrically and at right angles to the particular shaft rod and carry between them the heddles with in each case a central thread eyelet.

It is very disadvantageous in such arrangements that during their shed-forming operations the partial shafts necessarily perform an up and down movement in stepped and discontinuous manner between the individual partial shafts, so that it is not even possible to nearly reach a sought, continuous undulatory movement. It has hitherto only been possible to improve this undulatory movement and consequently the passage characteristics of the shuttles by using a large number of partial shafts, but this is limited considerably by the structural dimensions and in each case requires additional control means for each partial shaft.

It is therefore a problem of the present invention to so construct a shaft arrangement of the aforementioned type that it is possible to achieve therewith an at least approximately ideal undulatory movement whilst involving minimum constructional costs.

According to the invention this achieved in that the upper and lower heddle supports extend in each case between two adjacent shaft rods and are supported in an articulated manner on the latter, whilst being longitudinally displaceable.

As a result of these measures it is now possible to produce a substantially uninterrupted, continuous undulatory movement on the following heddles or in the vicinity of their thread eyelets in that the heddle supports can now follow the up and down movements of the particular shaft rods in a "smooth" manner due to their pivoting capacity. As a result of this arrangement far fewer partial shafts are used than hitherto, which considerably reduces the manufacturing costs for the loom, quite apart from the much better passage characteristics for the shuttles and the associated higher loom speeds.

Preferably the construction is such that the heddle supports are pivotably articulated to the shaft rod pairs in the movement plane thereof. It is advantageous if one end of the heddle support is in each case pivotably articulated about a pivot on the particular shaft rod, whilst its other end is longitudianlly displaceably supported on the particular shaft rod by means of a slot. One end of each heddle support can be constructed as a fork.

To ensure with the shaft arrangement according to the invention that the heddles do not slip on tilting the heddle supports, the latter can, for example, be notched. However, it is preferable if spacing members are arranged between the individual heddles, at least on each upper heddle support.

To prevent direct friction between the heddles and the heddle supports, both being generally made from steel, the construction can be such that each spacing member has a stepped offset shoulder on which is supported a heddle with one of its end eyelets. The spacing members are appropriately made from plastic.

It is also advantageous in the case of varyingly dense groups of threads for the spacing members to be interchangeable.

The invention is described hereinafter relative to non-limitative embodiments and the attached drawings, wherein show: Fig. 1 diagrammatically and in side elevation a circular loom.

Fig. 2 a plan view of the loom of Fig. 1.

Fig. 3 a diagrammatic projected view of a known embodiment of the shaft arrangement on the loom according to Figs. 1 and 2.

Fig. 4 a cutaway portion of the shaft arrangement of Fig. 3 in a perspective view, Fig. 5 A diagrammatic projected view of an embodiment according to the invention of the shaft arrangementforthe loom according to Figs. 1 and 2.

Fig. 6 a detail of the arrangement of Fig. 5 in a perspective view.

The undulating shed circular loom according to Figs. 1 and 2 in per se known manner rests on a loom base 1 on which is supported a circular frame member 2, carrying a circular reed 3, a loom onloff device 4 and further frame parts 5 for supporting partial shafts 6, 7. In the present case partial shafts 6 and 7 are arranged in two rows and in circular manner around the main shaft 8 of the loom. As a result outer partial shaft 6 and inner partial shaft 7 are formed, which spread apart the not shown warp threads to form a circulating undulating shed.

On base 1 is also supported the carrier 9 for the cloth removal device, which inter alia comprises the cloth removal drive 10, the cloth draw-off rolls 11, 12 and the cloth bale 13. A cloth expander 14 also acts in the removal area. It is also possible to see on the present loom the intake roll 15 for the warp threads on the left-hand side and the intake roll 16 for the warp threads on the right-hand side, as well as the overflow rolls 17 for the warp ribbons.

For the shed-forming operation of partial shafts 6, 7 as a function of the number and passage speed of the not shown shuttles for introducing the not shown weft threads and participating in the weaving process, in the vicinity of the loom base 1 the main shaft 8 and carries two plate cams 26, 27. The latter are in working connection via a plurality of pivoted levers 36, 37 distributed in radial manner about said cams with so-called shaft rods 46, 47 which, in per se known manner, are in working connection with the partial shafts 6,7.

To this extent the construction of the undulating shed circular loom shown corresponds to the prior art, so that a more detailed explanation of such a loom is superfluous.

In addition, the embodiment of a number of e.g.

external partial shafts shown diagrammatically and in projected form in Fig. 3 is generally known. These partial shafts 6 distributed in relatively large numbers around the loom have in each case an associated shaft rod 46 (Fig. 1) fixedly connected to an upper heddle support 50 and a lower heddle support 51, extending symmetrically and at right angles to the shaft rod and which support several heddles 52.

In per se known manner there is provided approximately in the centre of each ofthese heddles 52 a thread eyelet 53 through which is drawn in each case a warp thread F, as shown in Fig. 4.

As stated hereinbefore and as can be readily gathered from Fig. 3, this known shaft arrangement does not permit an even approximately ideal undulatory movement on the heddles 52 in the vicinity of the thread eyelets 53, because the raising and lowering ofthe individual partial shafts constructed in the aforementioned manner necessarily leads to a shed formation which takes place in a stepped, discontinuous manner between the individual partial shafts.

In order to obviate this problem the shaft arrangement according to the invention shown in Fig. 5 comprises upper heddle supports 150 and lower heddle supports 151 extending in each case between two adjacent shaft rods 46 and being articulated to the latter in such a way that heddle supports 150 or 151 can adapt by slope to the different stroke lengths of the shaft rods 46 on either side.

As can be seen from the view of Fig. 5 compared with that of Fig. 3 as a result of this arrangement according to the invention the thread eyelets 53 of the heddles 52 supported by heddle supports 150, 151 now follow a substantially ideal undulatory movement corresponding to the lifting movement on the individual shaft rods 46. To this end heddle supports 150, 151 are pivotably articulated to the shaft rod pairs in the movement plane thereof and this can be achieved in different ways. For example one end of each of the heddle supports 150, 151 is pivotably articulated about a pivot 54 to the particular shaft rod 46. The other end of heddle support 150, 151 is supported in longitudinally displaceable manner on the particular shaft rod 46 by means of a slot 55. The last-mentioned end of the heddle support can, for example, be constructed as a fork 56.

To prevent a slipping together of the heddles 52 when the heddle supports 150, 151 are in an inclined position both or only the upper heddle support can, for example, be provided with a rack-like profile in whose depressions are hung the heddles 52.

In the embodiment of Fig. 6 spacing members 57 are provided between the individual heddles 52.

These spacing members 56 are appropriately made from a plastics material and have an opening 60 enabling them to be mounted with a relatively large clearance on the particular heddle support 150. Each spacing member 57 has a stepped, offset shoulder 58 supporting the particular heddle 52 with an end eyelet 59. This measure prevents friction between the heddles and the heddle supports. As can also be gathered from Fig. 6 this also permits an easy adaptation to the different densities of the warp thread groups.

Thus, a shaft arrangement is provided which saris fies all the demands made of it and in particular permits a simple, reliably operating optimizable design of in particular a circular loom.

Claims (8)

1. Shaft arrangement of a loom, particularly a circular loom, in which in each case a plurality of inner and outer partial shafts are arranged in circular manner and in two rows around a main shaft of the loom and on whose shaft rods engage means for producing a shed-forming lifting movement, propagating in undulatory manner over all the partial shafts, upper and lower rod-like pedal supports carrying the heddles being supported on the shaft rods, characterized in that the upper and lower heddle supports (150,151) extend in each case between two adjacent shaft rods (46) and are supported in an articulated and longitudinally displaceable manner thereon.

2. Shaft arrangement according to claim 1, characterized in that the heddle supports (150, 151) are pivotably articulated to the shaft rod pairs (46) in the movement plane thereof.

3. Shaft arrangement according to claims 1 and 2, characterized in that one end of the heddle suppprts (150,151) is pivotably articulated about a pivot (54) to the particular shaft rod (46) and the other end thereof is supported in longitudinally displaceable manner on the particular shaft rod (46) by means of a slot (55).

4. Shaft arrangement according to claim 3, characterized in that one end of each heddle support (150, 151) is constructed as a fork (56).

5. Shaft arrangement according to one of the preceding claims 1 to 4, characterized in that spacing members (57) are arranged between the individual heddles (52), at least on each upper heddle support (150).

6. Shaft arrangement according to claim 5, characterized in that each spacing member (57) has a stepped, offset shoulder (58) on which is supported a heddle (52) with one of its end eyelets (59).

7. Shaft arrangement according to claims 5 and 6, characterized in that the spacing members (57, 58) are made from plastic.

8. Shaft arrangement according to claims 5, 6 and 7, characterized in that the spacing members (57, 58) are interchangeable.