GB2277328A - Needle or hook modules for tufting machine - Google Patents

Description

2277328 IMPROVEMENTS IN OR RELATING TO TUIFTING MACHINES This invention

relates to improvements in or relating to tufting machines and is more particularly concerned with improvements in the mounting of needles or hooks in the machine.

In tufting machines a plurality of yarn carrying needles are mounted on needle bars extending transversely across the machine and these needle bars are reciprocated cyclically to penetrate and insert loops of yarn into a backing material formed longitudinally beneath the needles. The loops thus formed are seized by either loopers or hooks mounted on a hook bar in conventional manner depending upon whether it is desired to produce loop or cut pile in the material.

In order to increase the ease with which a faulty or damaged needle or hook can be replaced, it has become common for small groups of needles or hooks to be mounted on a so-called needle or hook module and a number of these modules to be removably mounted on the needle or hook bar in side-by-side disposition to form rows of needles or hooks on the needle or hook bar respectively. Accordingly if one of the needles or hooks becomes damaged or worn, the needle or hook module in which that needle or hook is mounted can be removed and replaced.

Of course it will be appreciated that removing and replacing needle or hook modules onto the needle or hook bar necessitates that the new module(s) be positioned accurately on the bar to ensure accurate co operation with the corresponding needle(s) or looper(s) or hook(s).

1 -2 Needle or hook modules are usually secured to the respective bar by way of a single central screw. However such a securing renders it difficult to ensure accurate replacemen t of a damaged or worn module(s) and furthermore necessitates entire removal of the central screw from each module to be replaced.

It is an object of the present invention to provide a module capable of carrying needles or hooks which can be easily and conveniently positioned and removably secured accurately on a needle or hook bar.

According to a first aspect of the present invention therefore there is provided a module carrying a plurality of spaced yarn carrying needles or hooks, said module being adapted at opposite edges thereof to receive fastening means into bearing contact therewith which act to removably secure said module to said bar.

With this arrangement it is possible to ensure that a single or multiple needle or hook module(s) can be easily and conveniently removed for replacement or other means and can moreover be accurately replaced in position to ensure accurate co-operation with the corresponding needle or looper or hook.

Preferably said adaptation comprises a notch cut out on each respective opposite edge. Most preferably said notch is generally in the shape of half of a letter U.

Preferably said securing means comprises a screw threaded fastener which may have an enlarged head thereto. Most preferably a washer or clamping plates are used in conjunction with said fastener whereby said washer or clamping plates bear on a side of said module to secure it in place.

Preferably the module al so includes a -locating means which co operates with the. module and provides an accurate indication of a desired position for modules on a bar.

Preferably locating tabs are inserted into a recess between the modules, and are removably secured in such position, to identify precisely the position on the needle bar of a particular module.

A recess is preferably provided between said adaptation of opposite edges of the module, the recess being operative to receive a locator plate.

According to a second aspect of the present invention there is provided a module carrying a plurality of spaced yarn carrying needles or hooks, said module being provided with securing means and fixing means, said securing means removably mounting the module relative to a needle or hook bar of a tufting machine and said fixing means fixing said module against rotation thereof about said securing means.

According to a third aspect of the present invention there is provided a tufting machine including a plurality of modules according to the first aspect of the invention.

In order that the present invention may be more readily understood, specific embodiments thereof will now be described by way of example only with reference to the accompanying drawings in which:- 1 -4 Figure 1 is a schematic representation of one form of needle module in accordance- with the present invention; Figure 2 is a further module in accordance with the present invention; FigureS shows part of a further module in accordance with the present invention; and Figure 4 shows an alternative form of module in accordance with the present invention.

Referring now to Figure 1, there is shown a plurality of needle modules 11 carrying spaced apart yarn carrying needles 12 removably mounted on a needle bar 13. Each module 11 has a cut out 17 at each of opposite sides 14, 16 of an end thereof, the cut out 17 being shaped such that when multiple modules 11 are removably secured to a needle bar 13 end to end as shown in the figure, adjacent cut outs 17 on adjacent modules 11 form a generally U-shaped recess 18 between modules.

Each module 11 is removably secured to a needle bar 13 by inserting two fasteners 19, preferably screws, into the recesses 18 on each side 14, 16 of the module 11 to co-operate with a suitable securing means (not shown) on the needle bar, e.g. nut, screw threaded aperture. Once the fasteners 19 are tightened into the securing means the washers or clamping plates 21 bear against the module 11 thereby securing the module 11 to the bar 13.

It will be appreciated that the fact that the modules 11 are held in place by fasteners which bear against sides 14, 16 of the module 11 means that the stability. of the module 11 during'operation of the tufting machine is increased insofar as it is clear that a module secured by a single central screw will have a tendency to twist about the central screw when any significant force is applied to the needle at an angle to its direction of reciprocation, e.g. when passing through the backing material. A further advantage of the securing of the modules 11 bearing against the sides thereof is that a module -11 can be removed from -the machine without removal of the fasteners 19, it only being necessary to loosen the fasteners to an extent sufficient to allow the module 11 to be removed. Additionally, the particular end to end disposition of the modules 11 in combination with securing by bearing on the module 11 at the sides increases the combined stiffness of the arrangement of modules 11 and the needle bar 13 along the axis of the needle bar.

With the arrangement of the present invention it is also possible to provide for accurate replacement of modules 11 or groups of modules, by providing a locating tab 22 which can be inserted into the recess 18 between modules 11 to identify precisely the position on the needle bar 13 of a particular module 11. The locating tab 22 is secured relative to modules 11 by a suitable removable securing means. The tab 22 then provides a means for accurately positioning the module 11. It will be appreciated that it is not necessary to provide a locating tab 22 in each recess 18 since the manufacturing tolerances of the modules 11 are such that accurate position will not be lost over the extent of a single module 11, accordingly it is 1 tho'ught that it will only be necessary to provide locating tabs every few modules, e.g.. 4 to 10 modules to ensure accuracy to the desired degree.

Of course, should it be desired to do so, a tab 22 can be used for each module.

Referring now to Figure 2, aa alternative form.of module 30 for attachment to a needle bar 31 of a tufting machine is shown. The module carries a plurality of spaced apart yarn carrying les of books 32. The module 30 has a cut out 33 at each of opposite sides of an end thereof, the cut out being shaped such that when multiple modules 30 are removably secured to a needle bar 31 end to end as shown in the figure, adjacent cut outs 33 on adjacent module' s_ W form a generally U-shaped recess between the modules. Each module 30 is removably secured to the needle bar by inserting two fasteners (not shown), preferably screws, into the recesses 33 on each side of the module to co-operate with a suitable securing means (not shown) on the needle bar 31. Once the fasteners are tightened into the securing means then washers or clamping plates bear against the modules 30 thereby securing the module 30 to the bar in like manner to that described above in relation to the first embodiment.

In the module 30 shown in Figure 2, however, there is provided a further cut out 34 generally at the centre of a top edge 36 of the module, which cut out 34 is generally rectangular in shape. The cut out 34 of the module 30 is intended to co-operate with a locator plate 37 which is removably secured to the needle bar 31 by fasteners (not shown), e.g.

-7 screws, which extend through a central enlarged aperture 38 thereof into engagement with the needle bar 31. In use, once the needle or hook modules have been mounted on the needle bar, to ensure accurate co operation of the needle or hooks with the hooks or loopers of the tufting machine during operation, the position of the module 30 will be precisely identified on the needle bar by removably securing the locator plate 37 to the needle bar 31 in such a position that itco-operates. with the cut out 34.

Thus if the module 30 should ever be required to be removed for replacement or repair, the accurate replacement of the module 30 on the needle bar 31 can be ensured, it being simply a matter of locating the cut odt'34 6f"thd m6dulb 30 in co-operation With the locator plate -37 fixect onto the needle bar 31 as shown in the figure to ensure accurate location.

it will be appreciated that the locator plates 37 can be provided in a cut out 34 in one of every few modules, since it is thought that the manufacturing tolerances of the modules 30 will be such that accurate position will not be lost over the extent of a single or a few modules. Of course, if desired, a locator plate 34 can be used for each module.

Referring to Figure 3, an alternative module 40 similar to that described with reference to Figure 2 comprises a circular locator plate 41.

These modules containing circular locator plates 41 may be slidably moved into position more easily than modules containing non-circular locator plates.

A third embodiment of needle or hook module is shown in Figure 4.

In this embodiment of module, a central securing aperture 46 is provided in 1 the module through which a removable fastener (not shown) can be inserted to removably fasten the module to a needle or hook bar 47 of a tufting machine by co-operation with a securing means (not shown) on the needle bar. This fastener may be a fastener of the type discussed in relation to the first embodiment, and as shown in Figure 1, or alternatively can be any other form of fastener as desired or as appropriate. In this case however, cut outs are not provided at the side edges of the module, but two projecting fixing studs 48 are provided, one either side of the central securing aperture 46, which project from a rear of the module and can removably co-operate with corresponding recesses (not shown) in the needle bar 47 to secure the module against vertical, horizontal and rotational movement about the central fastener 46 when secured in position on the needle bar 47.

With this embodiment, the securing means and recesses (not shown) into co-operation with which the removable fasteners and studs extend may be provided directly in the needle or hook bar or alternatively may be provided in a backing bar (not shown) which is removably secured to the needle or hook bar. In the latter case, more than one backing bar may be provided, mounted in side by side disposition to each other in axial alignment, each backing bar mounting a small number of modules, e.g. 4 to 6, modules. The backing bars may be mounted on the needle bar 47 in such a manner that a limited amount of lateral adjustment can be made to the position of the backing bar on the needle or hook bar prior to the fasteners being tightened to secure the backing bar to the needle bar and, in order to -g- permit this, apertures in the backing bar through which fasteners can be removably inserted to fix the bar relative to the needle or hook bar may be elliptical or otherwise shaped to. allow this movement. This movement is particularly useful in allowing small adjustments to be made to the position of the modules whilst they are in position on the needle bar.

Whilst in the specific embodiments described, the invention is utilised in a needle module, it is clear that the invention can also be used in relation to a hook module for which similar considerations apply.

It is of course to be understood that the invention is not intended to be restricted to the details of the above embodiment which are described by way of example only.

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Claims (19)

1. A module carrying a plurality of spaced yarn carrying needles or hooks, said module being adapted at opposite edges thereof to receive fastening means into bearing contact therewith which act to removably secure said module to a needle or hook bar of a tufting machine.

2. A module according to claim 1 wherein said adaptation comprises a notch cut out on each respective opposite edge of the module.

3. A module according to claim 2 wherein the notch is generally in the shape of half of a letter U.

4. A module according to any one of claims 1 to 3 wherein said securing means comprises a screw threaded fastener.

5. A module according to claim 4 wherein said securing means has an enlarged head thereto to bear against said module.

6. A module according to claim 4 or claim 5 wherein a washer or clamping plates are used in conjunction with said fastener whereby the washer or clamping plates bear on a side of said module to secure it in place on the needle bar.

7. A module according to any one of claims 1 to 6 wherein a locating means is used in combination with said module which co-operates with the module and provides an accurate indication of a desired position for modules on the needle bar.

8. A module according to claim 7 wherein said locating means comprises a tab which is adapted to removably co-operate with said adaptation of the t module.

9. A module according to any preceding claim wherein tabs are inserted into a recess between the modules, and are removably secured in such position, to identify precisely the position on the needle bar of a particular module.

10. A module according to any preceding claim wherein a recess is provided between said adaptation of opposite edges of the module, the recess being operative to receive a locator plate.

11. A module carrying a plurality of spaced yarn carrying needles or hooks, said module being provided with securing means and fixing means, said securing means removably mounting the module relative to a needle or hook bar of a tufting machine and said fixing means fixing said module against rotation thereof about said securing means.

12. A module according to claim 11 wherein said securing means comprises a central aperture through which a fastener can be inserted into removable co-operation with the needle or hook bar.

13. A module according to claim 11 or claim 12 wherein said fixing means comprises a plurality of projecting studs which co-operate with corresponding recesses in the needle or hook bar.

14. A module according to claim 13 when dependent on claim 12 wherein a pair of fixing studs are provided on a rear surface of the module, one on each side of said central securing aperture.

15. A module according to any one of claims 11 to 14 wherein said 1 module is removably attached to a backing bar which in turn is removably attached to the needle or hook bar of a tufting machine.

16. A module according to claim 15 wherein said backing bar is removably' attached to the needle or hook bar by way of a fastener extending through a backing aperture on the bar into co-operation with the needle or hook bar, the backing aperture being shaped so as to allow lateral movement of the backing bar relative to the fastener for adjustment purposes.

17. A module according to claim 16 when said backing aperture is generally elliptical.

18. A module substantially as hereinbefore described with reference to Figures 1, 2 and 3 or 4 of the drawings.

19. A tufting machine including a plurality of modules according to claim 1 or claim 11.

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