GB1568201A - Heald and a method for the manufacture thereof - Google Patents

Abstract

Heald (10) composed of textile thread, which consists of two crocheted threads (11, 12) and in which each individual knot, which, in the healds known hitherto, connects the two twisted or smooth thread parts to form the heald eye, is replaced by interlaced ladders of two stitches located next to one another in the two crocheted threads (11, 12). The looping points (13, 14, 15, 16) are formed at predetermined points along the two threads, for the purpose of producing the closed heald with its eye (17). This novel heald is produced on a knitting machine with a constant bundle length and is then combined in a bundling machine. The use of the novel heald does away with all the problems which occur in tying by hand, such as for example, time-consuming work, and knots which, in the few thousand healds located next to one another on the heald frame, are considerably thicker than the actual thread material and form bulges which give the combined healds a non-uniform width. <IMAGE>

Description

(54) A HEALD AND A METHOD FOR THE MANUFACTURE THEREOF (71) I, SUNB INGEMAR IVARSSON, a Swedish subject of Alehemsvägen 18, 44600 AIvangen, Sweden, do hereby declare the invention for which I pray that a Patent may be granted to me and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention refers to a heald of the type, hereinafter referred to as "of the type described", made from textile thread and having a mounting loop at each end and a central eyelet for supporting a yarn in a loom, and to a method for the manufacture thereof.

Such healds are used for hand looms, and these healds have, since time immemorial, been made by tying a thread manually into a three-part loop, by means of three knots. This is a very time-consuming job, as between one thousand and three thousand healds are required for a loom of normal width, depending on the fabric to be woven, and as a trained heald tier can make a maximum of about 800 healds during an eight hour day. When it is considered that the thread healds are sensitive to wear and therefore have to be replaced regularly, it is easily understood that it can be difficult to meet the demand for hand-tied thread healds.The possibility of hiring more heald tiers is also limited as the payment for the work amounts to only a few Swedish öre for each tier heald, which means that the daily earnings for a heald tier in Sweden will be only some 10 Swedish Crowns. The work must therefore to a large extent be therapy work and the like. This means that there is always a latent need for hun dress or thousands of healds, which in turn leads to waiting time for those who wish to replace their worn-out healds or who wish to buy a new loom.

The manual tying furthermore gives raise to problems regarding stock-keeping and handling, as two tiers will not necessarily make uniformly tied thread healds. It is therefore necessary for heald retailers to store the production of each tier separate from that of other tiers and also to keep records over the type of healds delivered to every separate customer for making it possible to give the customers the same type of healds, having the particular properties given to the mby "their own" heald tier at a later replenishment or when a worn out set of thread healds shall be replaced.

Another drawback of these hand-tied thread healds is that the knots are more than twice as thick as the thread. As one thousand or more healds are pressed against each other on heald rails for forming the shed it is understood that the knots which are arranged level with each other will form bosses, which can damage the warp or become damaged by this.

An object of the invention is to provide an-improved heald - of th- type de-s-cribed and a method of making it by which the above disadvantages are obviated or minimised. Accordingly the invention provides a heald of the type described formed by passing two threads side-by-side through a knitting machine to crochet each thread and crocheting the two threads together at predetermined spaced-apart positions to form the loops and the eyelet.

The invention also provides a method of making a heald of the type described comprising passing two threads side-by-side through a knitting machine to crochet each thread and crocheting the two threads together at predetermined spaced-apart positions to form the loops and the eyelet.

The invention also provides a method as aforesaid in combination with a step of bundling the produced healds conveniently by storage and transportation.

The invention will hereinafter be further described, by way of example, with reference to the accompanying drawings, wherein: Fig. 1 shows a conventionally hand-tied heald in which the knots have not been tightened for the sake of clarity; Fig. 2 shows in a view corresponding to Fig. 1 a heald according to the invention; Fig. 3 is a view on a larger scale of a portion of the heald according to the invention and showing a connection point; Fig. 4 shows how a plurality of continuously connected healds according to the invention are arranged on heald rails; and Fig. 5 is a schematic side view of a device for bundling healds according to the invention.

Fig. 1 shows a heald 1 of a conventional hand-tied type, which consists of a single thread (preferably of a comparatively soft material), which is twisted to a string 2 of suitable thickness. This string is at three positions provided with knots 3, 4, 5 which for the sake of clarity are shown not tightened and which knots have been tied manually. These knots form the end portions and the eyelet 6 of the heald. It is easily understood that a large plurality of healds arranged on rails will give the bundle of healds a considerably larger -thickness > tk level of the various knots than at the portions ttheixrdlc--whic-h- have no knots.It shall hereby be considered that each knot from a general point of view is more than twice as thick as the heald thread itself and that one thousand or more healds aranged on the rails will of course give a highly varying bundle thickness in the longitudinal direction of the rails. The reason for using a comparatively soft material for this conventional hand-tied thread heald is that the bosses formed by the knots could damage the warp if the material was not soft and comparatively flexible. This in turn means that the heald has a comparatively short service life as the wear will be relatively rapid due to the soft material which has a low resistance to wear.

It is furthermore difficult for an untrained tier to tie the thread of such a heald in such a manner that the heald eyelet will be situated at the same distance from the ends of each heald of a long series of similar healds in spite of use of aids such as frames and the like.

In Fig. 2 is shown a heald 10 according to the invention, which heald consists of two crocheted threads 11 and 12 provided with connecting points 13, 14, 15 and 16, which form the heald and its heald eyelet 17. As can be better seen in Fig. 3, which shows a part of a connecting point in larger scale, the connecting points 13, 14, 15 and 16 are made in such a manner that a loop in one of the threads 11 is crocheted to grip into a loop of the other thread 12 to form a connecting point, the thickness of which is considerably less than the thickness of the knots in conventional hand-tying. As the problem of bosses forming at the threading of a plurality of healds on heald rails is eliminated it is possible to use a considerably stronger thread as initial material for the heald without thereby achieving the negative ef fect that the warp can be worn by the heald.It is hereby possible to obtain a longer service life for healds of this type as compared to conventional, hand-tied thread healds.

The crochet heald according to the in vention is preferably made in a hosiery machine, e.g. a raschel knitting machine, which works automatically and which with simple aids can be adapted to produce healds in continuous lengths with accu rate heald lengths and precise location of the eyelet in the heald. The problem of keeping the production of different heald tiers in stock is hereby eliminated as all healds made with that sepcific machine or with a similar machine are exactly simi lar. The length of continuous healds is preferably provided with intermediate por tions 18, which allow a fret adjustability =between--the-separate healds at the thread ing of the healds on heald rails 19.An advantage at this type if production is that the heald can be supplied as a piece goods sold by the metre, whereupon it can be threaded at a convenient time and at an apropriate place upon heald rails, which is clearly in contrast to hand-tied healds, which are tied one by one separately, and prior to the subsequent delivery must be threaded upon frames. When threading healds on heald rails it can now and then happen that one or more healds are threaded wrongly. As it is possible simply to cut off the heald which has been placed wrongly by cutting off the intermediate parts 18.

It is possible by use of only one hosiery machine to produce between 25,000 and 50,000 healds according to the invention in one working day, whereby the separate healds thus made can have exactly the same dimensions and furthermore appre ciable thickness variations are eliminated because the knots are eliminated. Due to the simple manufacture it is also possible to make healds of this type at costs which are favourable compared to the costs for the hitherto common conventional, handtied healds in spite of the very poor payment for such hand-tying.

The method of the invention preferably includes the additional step of automatically bundling the healds and a device capable of carrying out this step is schematically shown in Fig. 5. The continuous length of healds 20 when produced in the knitting machine is preferably collected in a container. The length of healds 20 is led from said container (not shown) through a knot detector fitted in a frame 21 and comprising a pivotably supported lever 22 having an aperture, through which the length of healds is threaded. The pivotable lever 22 when lifted by a knot too large to pass through the aperture, pivots to a position, in which it acts upon a contact 24. This contact 24 indicates the presence of a knot and/or stops the operation of the bundling device if a knot exceeding a pre-determined size appears.The length of healds 20 is next led through a thread brake 25 and therefrom to a thread stretcher, which also acts as a knot detector and like the first mentioned knot detector consists of a pivotable lever 26 having an aperture, which second lever 26 cooperates with a contact rail 27, which when acted upon by the lever 26 will stop the operation of the device, e.g. by cutting off the power supply thereto. The lever 26 is biased by a spring 28 to stretch the length of healds as desired.The length of healds passes from the aperture in the lever 26 to a threading-in lever 29, which is pivotably supported and adapted to make a reciprocating movement about its support point whereby it, when moving in one direction (towards the right in the figure), carries a point of the continuous length of healds positively and positions this over a threading fork 30 by releasing the said point at the commencement of its reciprocating movement in the opposite direction, whereby the closed loops on each side of the heald eyelet in each heald will each be threaded over a fork arm of said threading fork 30. When a heald has been threaded upon the threading fork 30 in this manner a heald retainer 31 seizes the thread heald and moves it downwards. This is repeated until the desired bundle size (e.g. 100 healds/bundle) has been reached.

By aid of this bundling device is it possible to make the production of healds according to the invention highly automatic.

The invention is not limited to the embodiments shown in Figs. 2-5 and described in connection thereto but it can be modidied within the scope of the following

Claims (1)

1. claims.

   WHAT I CLAIM IS:

   1. A heald of the type described formed by passing two threads side-by-side through a knitting machine to crochet each thread and crocheting the two threads together at predetermined spaced-apart positions to form the loops and the eyelet.

   2. A heald as claimed in claim 1 and connected to an intermediate portion, also formed of said threads, and linking it to a succeeding similar heald.

   3. A heald, of the type described, substantially as hereinbefore described with reference to and as illustrated in Figs. 2, 3 and 4 of the accompanying drawings.

   4. A method of making a heald of the type described comprising passing two threads side-by-side through a knitting machine to crochet each thread and crocheting the two threads together at predetermined spaced-apart positions to form the loops and the eyelet.

   5. A method as claimed in claim 4 wherein the knitting machine is a Raschel Knitting machine.

   6. A method as claimed in claim 4 or 5 including the step of forming from said threads an intermediate portion between the heald and a next succeeding heald also made from the threads.

   7. A method of making a heald of the type described substantially as hereinbefore described With reference to Figs. 2, 3 and 4 of the accompanying drawings.

   8. A method as claimed in claim 6 in combination with the step of passing a continuous length of healds so produced to a bundling machine comprising a threading lever mounted for reciprocating movement about one end and having a heald carrying aperture at its other and mounted to reciprocate adgacent a receiving fork whereby reciprocating movement of the lever transfers the end loops of each heald alternately onto each tine of the fork, and a heald retainer acting to retain each heald after it has been threaded onto the fork, so that the continuous length of healds is converted into a bundle of parallel-lying healds.

   9. A combination as claimed in claim 8, including, in the bundling step, passing the heald length through a knot detector comprising a pivoted member having an aperture of predetermined size, which is adapted upon being pivoted by a knot in the length greater than the size of the aperture, to actuate means for stopping the bundling or giving a warning.

   11. A combination as claimed in claim 8 or 9 substantially as hereinbefore described with reference to Fig. 5 of the accompanying drawings.