US2389809A

US2389809A - Method and device for cutting weft thread ends projecting from the fabric

Info

Publication number: US2389809A
Authority: US
Inventors: Moessinger Albert
Original assignee: Sulzer AG
Current assignee: Sulzer AG
Priority date: 1942-06-11
Filing date: 1943-03-18
Publication date: 1945-11-27
Anticipated expiration: 1962-11-27

Description

Search Roon Nov. 27, 1945. A. MOESSINGER 2,389,809

METHOD AND DEVICE FOR CUTTING WEFT THREAD ENDS PROJECTING FROM THE FABRIC Filed March 18, 1943 2 Sheets-Sheet 1 ALQBAY'RTMOEJSINGER.

ATTORNEY.

Nov. 27, 1945.

A. MOESSINGER METHOD AND DEVICE FOR CUTTING WEFT THREAD ENDS PROJEC'IING FROM THE FABRIC Filed March 18, 1943 2 Sheets-Sheet 2 INVENTOR. I ALazkrMo SINGER.

BY/(l ATTORNEK y n-mum Patented Nov. 27, 1945 SEBTCH H METHOD AND DEVICE FOR CUTTING WEFT THREAD ENDS PROJECTING FROM THE FABRIC Albert Moessinger, Winterthur, Switzerland, assignor to Sulzer Frres, Socit Anonyme, Winterthur, Switzerland Application March 18, 1943, Serial No. 4795539 In Switzerland June 11, 1942 Claims.

When weaving on automatic looms, at each change of bobbins a, piece of the weft from the old bobbin and a piece from the new one will project from the edge f the fabric. In multiplebox looms the various weft threads will make loops which project from the fabric. In gripper looms, where the thread is cut off after each insertion, the weft threads also project from the fabric. All these projecting weft threads diminish the selling value of the fabric. The devices hitherto known for cutting off the ends of the weft threads are either so complicated that they have not been introduced into weaving practice, or so imperfect that the cut-off weft thread ends still project from the edge of the fabric. Through the present invention the weft thread ends can be cut ofi with very simple means at an exact and alway uniform distance from the edge of the fabric.

The invention relates to a method and a device for cutting off the ends of the weft thread projecting from the fabric and consists in that the projecting weft thread ends are bound together by binding threads running in the direction of the warp, and that the projecting weft thread ends are cut off between the fabric and the outermost binding threads which are held in tension. The device for carrying out the method consists in that the projecting weft thread ends are bound together by binding threads controlled by the loom in a known manner, that a cutting device severs these weft thread ends between the fabric and the binding threads, and that the outermost binding threads are kept in tension by a tensioning device.

The weft threads can be connected by a continuous rotation of the binding threads (twist binding). The binding threads can change their shed when the shuttle is at the other side of the fabric. The binding threads may change their shed at each pick. According to the invention a pair of binding threads close to the warp threads and a second pair of binding threads a little further from the fabric bind the weft threads together, and the weft threads are cut off from the fabric between the two pairs of binding threads. The cutting device may be movable in the direction of the weft threads and be pressed lightly either towards the fabric or towards the outer binding threads. The binding threads when separated from the fabric may be kept in tension by and wound on to a bobbin driven through a friction coupling by the machine.

In Figs. 1 to 4 some examples of embodiments of the invention are shown diagrammatically.

Fig. 1 shows the fabric I with the weft thread ends 2 projecting from it. Close to the warp threads 3 the weft threads 2 are connected together by a pair f binding threads 4. A little further away from the fabric, the weft threads 2 are again connected together by a second pair of binding threads 5. Between these two pairs of

binding threads

4 and 5 the weft threads 2 are cut by a knife 6. The knife 6 is fixed to one arm I of a double armed lever which is pivoted at a fixed point 8. A second arm I, at right angle to the arm I, is acted on by a spring 9 which is connected to a fixed part [0. Under the influence of this spring 9 the knife 6 is pressed close to the binding threads 4 beside the warp threads 3. In this way the cut weft thread ends projecting from the fabric I and/or from the binding threads 4 become quite short and always of the same length. Depending on the extension of the knife from the cutting-edge 2| to the side 20 pressed against the fabric, the weft thread ends, after being cut by the knife, will still project more or less from the fabric. The other pair of binding threads 5 is led over

guide rods

22, 23 and rolled up on a tensioning device consisting of a bobbin ll driven through a friction coupling I3, IS. The severed weft thread ends may for instance, be treated as waste or used again. A chain wheel I2 is pivotally mounted on a bolt l6 and is rotated continuously by the loom through the chain l4. On this chain wheel l2 a friction lining I3 is fixed. The bobbin l I has also a friction lining l5 and can rotate freely on bolt Hi. This bobbin is pressed by a spring I! and a plate [8 axially to the chain wheel l2, so that the bobbin II is rotated by the friction linings l3 and IS. The force turning the bobbin H keeps the pair of binding threads 5 in tension and winds them onto the bobbin.

Fig. 2 shows a side view of the knife 6 which cuts the weft threads. The cutting edge 2| of the knife is preferably arranged obliquely to the plane of the fabric I. The knife 6 is screwed to an angle-iron extension piece 1 on the lever 1. In Fig, 3 an example of a fabric made on a multiple-box loom is shown, in which the outermost binding threads change their shed when the shuttle is at the other side of the fabric. The weft threads 25 connected to each shuttle in the change boxes not shown in the drawings, are connected together by the outermost pairs of binding threads 26 at some distance from the edge of the fabric 24. These binding threads 26 are in accordance with the invention 'zept in tension and the weft threads projecting from the fabric are severed close to the fabric 24 by the knife 21. Along with the binding threads 26 the severed ends 25 are drawn away and rolled up on a bobbin II as shown in Fig. 1. Since all severed weft threads ends are thus removed from the machine, no suction apparatus or the like is required for their removal.

Fig. 4 also shows another example of a fabric made on a multiple-box loom and trimmed according to the invention. In this case, however,

the outermost pair of binding threads 32 changes shed at each pick, so that not only the weft threads connected to the shuttles in the changebox, but all the weft threads are connected together. In this case it will be preferable to provide a second pair of binding threads 34, closer to the fabric, in order to make a proper edge to the fabric. The weft threads 30 are cut by the knife 33, and the connecting threads 32 are kept in tension by a tensioning device not shown in the figure.

With the present invention it is possible, with very simple means and very neatly, to cut the weft threads projecting from the fabric. This cutting can be don directly on the loom, thus making it unnecessary to pass the woven material through a special expensive shearing machine.

I claim:

1. In a loom for weaving, a mechanism for cutting the weft threads extending in a fabric between two pairs of warp threads, said mechanism comprising a knife blade positioned at a substantially right angle to the plane of the fabric and having a substantially straight cutting edge in inclined position with respect to the fabric and extending through and severing the weft threads between the pairs of warp threads when the fabric is moved in the direction running up said inclined edge, and a support member mounted on the loom swingably about an axis substantially at right angle to the fabric, said knife blade being connected with and supported by said support member,

2. In a loom for weaving, a mechanism for cutting the weft threads in a fabric between two warp threads, said mechanism comprising a knife holder mounted on the loom swingably about an axis substantially at a right angle to the fabric, a knife blade connected with said holder and being positioned at a substantially right angle to the fabric and having a cutting edge in inclined position with respect to the plane of the fabric and extending through and severing the weft threads between said warp threads when the fabric is moved in a direction running up said inclined edge, and actuating means connected with said holder and moving said holder so that said blade is pressed toward one of said warp threads.

3. In a loom for weaving, a mechanism for cutting weft threads extending from the woven fabric between the outermost warp threads and the next inner warp thread, said mechanism comprising a knife blade disposed laterally movably and at a substantially right angle to the plane of the fabric and having a cutting edge in inclined position with respect to the fabric and extending therethrough and severing the weft threads between said outermost warp threads and the next inner warp thread, and tensioning means maintaining tension on said outermost warp threads.

4. In a loom for weaving, a mechanism for cut-- ting weft threads between an outermost warp thread and an inner warp thread, said mechanism comprising a knife blade disposed at a substantially right angle to said weft threads and extending therethrough and severing the weft threads between said outermost warp thread and said inner Warp thread, tensioning means maintaining tension on said outermost warp thread, and a knife holder connected with said blade and mounted on the loom swingably about a fulcrum disposed substantially at a right angle to said warp and weft threads and affording a laterally swinging motion of said blade between the outermost warp thread and the inner warp thread.

5. In a loom for weaving, comprising a mechanism as set forth in claim 4 and having resilient means connected with said holder resiliently pressing said blade toward said inner warp thread.

6. In a loom for weaving, a mechanism for cutting the weft threads extending in a fabric between two pairs of warp threads, said mechanism comprising a knife blade holder mounted on the loom swingably about an axis substantially at right angles to the fabric, a knife blade rigidly connected with said holder and being positioned at a substantially right angle to the fabric and having a cutting edge in inclined position with respect to the plane of the fabric and extending through and severing the weft threads between said pairs of warp threads when the fabric is moved in the direction running up said inclined edge, said knife blade being relatively thick and said edge extending between the planes in which the sides of said blade are located whereby the warp threads adjacent to the blade are held at a distance from the cutting edge and protected against being cut.

7. The method of cutting off the weft thread ends projecting from the fabric while it is still on the loom on which it has been woven, comprising the steps of tensioning the outermost warp threads separately from and independently of the fabric after they have been woven-in in spaced relation from the remainder of the warps, and of cutting the weft threads adjacent to the inside of the separately tensioned warp threads.

8. The method of cutting the weft thread ends projecting from the fabric while it is still on the loom on which it has been woven, comprising the steps of applying tension to the outermost warp threads substantially in the direction of the movement of the fabric and after they have been woven-in in spaced relation from the remainder of the warps, and of cutting the weft threads inside of said tensioned outermost warp threads and at a point separated from the last beaten up weft thread by a plurality of woven in weft threads.

9. The method of cutting off the weft thread ends projecting from the fabric while it is still on the loom on which it has been woven, comprising the steps of tensioning the outermost warp threads separately from and independently of the fabric after they have been Woven-in in spaced relation from the remainder of the warps, of cutting the weft threads between the tensioned warp threads and a warp thread which is inside of said separately tensioned warp threads, and of drawing said outermost warp threads away from the fabric.

10. The method of cutting off the weft thread ends projecting from the fabric while it is still on the loom on which it has been woven, comprising the steps of tensioning the outermost warp threads, after they have been woven-in in spaced relation from the remainder of the warps, separately from and independently of the fabric and substantially in the direction of the movement of the fabric, of cutting the weft threads between the tensioned warp threads and a warp thread which is inside of said separately tensioned warp threads, and of drawing said outermost warp threads away from the fabric after the weft threads connecting said warp threads with the fabric have been cut.

ALBERT MOESSINGER.