US2495501A - Means for detecting caught threads in circular looms - Google Patents

Description

Jan. 24, 1950 v M J ANCET 2,495,501

' MEANS FOR DETECTING CAUGHT THREADS IN CIRCULAR LOOMS Filed- March 18, 1948 Patented Jan. 24, 1950 Victor 'Marie Joseph Ancet, Lyons, France, as-

signor to Regina S. A., Tangiers, Morocco r Application March is, 1948,, Serial No. 15,556 In France March 31, 19/97 This invention relates to loom stop motions I and is concerned more particularly with a novel .stop motion, whichoperates to stop the loom in the event that the warp shed is not properly openedfor'the passage of the shuttle. Thenew stop motion may ,be utilized in looms of various types and is especially adapted for ,use'on circularlooms. An application of the stop motion to a circular 100m of the type, in which the warp threads undergoing shedding [extend verztically, will, accordingly, be illustrated and describedin detail fforpurpos'es of explanation.

, In the operation o'floomsfit sometimes happens that the shed .does not open properly to permit the shuttle to pass through it and this may result from-a-deiectin the shedding mechanism or because of the presence of a foreign body among-the'warp threads. "In circular looms, in particular, the breaking of a warp thread permits the :thread to drop down -and -the broken thread may be carried along by the shuttle, so that it takes the position of 'a weft thread that has been improperly-inserted, andhindersor'prevents the opening of the shed in the next shedding operation. When the warp threads are not properly separated into two sheets of a shed through which the shuttle may pass, the shuttle should be stopped promptly and before it reaches the obstruction, since otherwise damage may be done to the warp.

Heretofore, a number of expedients for stopping a loom upon the occurrence of an insufliciently opened shed have been proposed, but such devices have acted in response to contact of the shuttle with the warp threads not properly separated in the formation of the shed. As a result, the proposed stop motions have necessarily functioned to effectso rapid a stoppage of the loom as to put a strain upon it and, in order that they may be effective, it has been necessary to limit the speed of the shuttle.

The present invention is, accordingly, directed to the provision of a novel stop motion for looms, which functions to stop the loom upon the occurrence of an improperly formed shed and before the shuttle has come into contact with the obstruction in the shed. When the new stop motion is employed on a circular loom, in which shedding is a gradual operation, a considerable interval of time is available after the functioning of the mechanism'before the shuttle can reach the obstructedpartof the shed, sothat the shuttle may be driven at a high speed.

For a'better understanding of the invention, reference may be made 'to .the accompanying drawing, in which Fig. 1 is a diagrammatic perspective view of portions of a circular loom equipped with the new stop motion; and

Figs. 2 and 3 are fragmentary plan views of the stop motion, showing its mode of operation.

The circular loo'm diagrammatically illustrated in Fig; 1 includes an axial main shaft 10, which operates through mechanical or electromagnetic means '(not shown) for propelling one or more shuttlesll through a .circularpath above a reed 1'2. The .warp threads 13 are manipulated by 'harness'mechanism "(notshowm to form a shed, through which each shuttle moves,'the shed opening ahead ofth'e shuttle and closing behind it, asit travels along.

' An arm f4 for each shuttle is mounted on shaft +0 to extend toward the warp threads and the arm rotates with the shaft and lies ahead of its shuttle in the direction of travel of the latter. At its outer end, each arm carries a plate 15 of insulating material and a metal detecting finger I5 is mounted for swinging movement on a metal pin l1 extending through the plate. Thefinger is connected through a spring l8 to a post i9 mounted on the plate and is urged by the spring to swing toward a fixed terminal 20 carried by the plate. The pin I1 is connected in a circuit with a solenoid 2| and a battery 22, one side of which is grounded, and terminal 2! is grounded through a connection 23. The plate I5 is slotted and held adjustably on arm l4 by a screw 24 passing through the slot and into the arm.

Solenoid 2| operates, when energized, to open switch 25 in a circuit with control means 26 controlling the supply of current to motor 21 driving the loom. When switch 25 is opened, the control means cuts off the current to the motor and the loom stops.

In the use of the new stop motion, plate I5 is initially adjusted on the arm It, so that the s end of finger l6, which extends beyond the edge of the plate, projects into the inner sheet of warp threads in the fully opened shed, that is. into the sheet lying closer to the loom axis. As

shaft It rotates carrying arm M with it, finger 16 engages the warp threads l3 in the inner sheet successively and, as the finger snaps by one warp thread, it engages and is held back by the next, so that it cannot engage the terminal 23. If a warp thread, such as that designated Isa, breaks and drops down, it is likely to be carried along by one shuttle, so that, when the shed is to be opened for the following shuttle, thread I30, will prevent the shed from opening. When that occurs, the finger I6 of the stop motion preceding the second shuttle will reach a point adjacent the obstructed thread, where there is no warp thread in its path. The finger will, thereupon, be swung by its spring 18 against contact 26. This will complete the circuit through solenoid 2| and switch 25 will be opened to cut off the supply of current to the motor 21, so that the loom will stop.

It will be apparent that, with the construction described, the stop motion, which prevents engagement of a shuttle with an obstruction in the shed, lies a substantial distance angularlyahead of the shuttle. The interval between actuation of the stop motion and stopping of the loom, may, therefore, be much longer than would be permissible, if the stop motion were carried by the shuttle assembly, so that the loom may be stopped with less strain. Also, for the same reason, a higher shuttle speed is possible.

What I claim is:

1. In a loom having driving means, means actuated by the driving means for forming the warp threads into a shed, a shuttle moved through the shed by the driving means, and means controlled by an electric circuit for stoppingthe loom, the combination of a mounting advanced by the driving means along the path of the shuttle and ahead of the shuttle, a contact forming part of the circuit and carried by the mounting, a detectorfinger movably mounted on the mounting and normally engaging successive warp threads forming one sheet of the shed,

the finger being in the circuit, and a spring acting on the finger and urging it toward the contact to close the circuit, the finger being held by its engagement with the warp threads in said 4 sheet from being moved into engagement with the contact.

2. In a loom having driving means, means actuated by the driving means for forming the warp threads into a shed, a shuttle moved through the shed by the driving means, and means controlled by an electric circuit for stopping the loom, the combination of a mounting advanced by the driving means along the path of the shuttle and ahead of the shuttle, a contact forming part of the circuit and carried by the mounting, a detector finger pivotally mounted on the mounting with one end normally engaging successive warp threads forming one sheet of the shed, the finger being in the circuit, and a spring acting on the finger and urging it to swing to engage the contact and close the circuit, the finger being held against such swinging movement by its engagement with the warp threads in said sheet.

3. In a loom having driving means, means ac- I warp threads into a shed, a shuttle moved through the shed by the driving means, and means controlled by an electric circuit for stopping the loom, the combination of an arm rotated on the axis of the loom by the driving means and lying ahead of the shuttle, a contact mounted on and insulated from the arm, the contact being in the circuit, a detector finger movably mounted on and insulated from the arm, the finger being in the circuit and normally engaging successive warp threads in one sheet of the shed, as the arm rotates, and a spring urging the finger toward the contact to close the circuit, the finger being held by its engagement with the threads in said sheet from being moved to engage the contact.

VICTOR MARIE JOSEPH ANCET.

REFERENCES CITED UNITED STATES PATENTS- Name Date Jabouley July 9, 1935 Number

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