US3390708A - Weft-fork for a weaving loom - Google Patents

Description

July 2, 1968 v. SCHERILLO WEFT-FORK FOR A WEAVING LOOM Filed May 31, 1966 INVENTOR. vzffan'a .Smm-uo l2 BY nul'm T 3,390,708 WEFT-FORK FOR A WEAVING LOOM Vittorio Scherillo, Milan, Italy, assignor to Nuovo Pignone S.p.A., Florence, Italy, an Italian company Filed May 31, 1966, Ser. No. 553,977 Claims priority, application Italy, June 11, 1965, 13,184/65 2 Claims. (Cl. 139370) ABSTRACT OF THE DISCLOSURE To stop a loom if a weft thread is broken, not inserted, or unduly slackened, a feeler is provided which has one end pivoted in a box carried by a pivotally adjustable support. The other end of the lever will contact the weft thread and be lifted upwardly by the weft thread to open a switch in the box if the weft thread is present. A spring in the box urges the lever constantly downwardly to close the switch. A cam closes a second switch on each cycle of reciprocation of the reed. When both switches are closed the circuit to the stop mechanism is made to stop the loom.

This invention relates to a device for. automatically stopping a weaving loom in which case a weft thread is not inserted or is broken or slackened.

In a continuous weft-supply loom, wherein the thread is taken out of a reel, and through conveying devices, is brought into the shed and then disengaged at the end of said shed, it may happen that the thread is broken or slackened thus giving rise to a fault.

The principal object of the present invention is just to provide a weft-fork device adapted to check the presence of the weft thread in the last inches of the fabric, so as to signal even mere slackening of said weft thread, thus causing the immediate stoppage of the loom.

The invention is illustrated in the accompanying drawings, which are given by way of example only and without implying any limitation, in that the adoption of constructional arrangements or of equivalent members other than those suggested herein, lie within the scope of this invention.

FIGS. 1 and la are elevational views taken at right angles to each other and showing a weft fork lever constructed according to one embodiment of this invention, and the supporting arm therefor.

FIG. 2 is a view on a somewhat enlarge-d scale showing the position of the feeling blade.

FIG. 3 is a view showing the feeling blade when no weft-thread has been inserted.

FIG. 4 is a diagram illustrative of the electric circuitry of the device.

The weft-fork device, which is the subject of this invention, comprises a stiff supporting member 1, arranged outside the warp threads 20 in the right side of the fabric, which member rigidly connects the box 2 to a fixed part of the loom. Furthermore, it is positioned behind the reed 10, in such a location that the latter, in its motion, is not hindered by said supporting member. The supporting member 1 is adjustable on the loom frame, and be secured in any adjusted position by bolts 18 which pass through slots 19 in the supporting member and thread into the frame.

The connection between the box 2 and the supporting member -1 is via an adjustable pivot 14, which allows arranging the box 2 adjacent the shed while maintaining said box outside the shed in such a position as to avoid the warp threads 20, in their shedopening movement, interfering therewith.

The box 2 carries the pivot 3 which is a fulcrum for the weft-fork lever '4, positioned outside the box 2.

3,399,708 Patented July 2,1968

To the pivot 3, within the box 2, is afiixed a lever 5 carrying at its end a tungsten-point 6 which forms one of two electric contacts, the other one 15 being affixed to the uppermost wall of the box 2.

A spring 7, whose pressure can be adjusted by a screw 8, is a biasing member for the lever 4, while the stud 9 is a member which defines the lowermost positionof said lever.

The weft-fork lever 4, which as shown in FIGS. 1, 2 and 3 is supported above, and substantially completely outside of the warp shed, passes through the teeth of the reed 10, having a length suflicient to stay constantly on the fell of the previously woven fabric, and between the reed teeth throughout the stroke of the reed: furthermore, its lowermost portion 11 is shaped so as to be situated partially under the ideal central plane 17 of the warp opening (see FIG. 3) when no weft thread is present. Whenever the weft w is picked by the reed, said weft, in its displacement towards the already woven fabric portion, comes into contact with the curved portion 11 of the blade 4, lifting the latter and causing the two electric confacts 6 and 15 to be opened.

Said contacts are norm-ally closed contacts but they do not normally send any signal to the loom-stopping relay 16 because the weft-fork electric circuitry passes through an electromechanical current-delivering device formed by a switch 12 and a cam 13 driven by the loom crankshaft (see FIG, 4), which allows the delivery of the signal to the loom-stopping relay 16 only in the time interval when the weft-fork is activated.

The electromechanical distributor, thus, by the intermediary of the cam 13, establishes the activation times of the weft-fork with respect to the weft-insertion stage.

The actuation of the weft-fork, in the present case, is limited to the time in which the weft begins to lift the blade 4 and until such time as the weft is picked against the already woven fabric port-ion.

Then, as the weft is regularly picked, the lifting of the blade 4, by opening the electric contacts 6 and 15, prevents a signal from being forwarded to the loom-stopping relay, whereas, when the weft thread is lacking or undergoes a considerable slackening, the blade 4 remains in its depressed position, the contacts 6 and 15 stay closed and, by coinciding 'with the active phase of the electromechanical distributor 12 which, in the instant of time in which the weft is to be picked, is closed, via the cam 13, a circuit is made to the loom-stopping relay 16 to stop the loom.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. The combination with a weaving loom having a frame, a toothed reed reciprocable on said frame, a cam operated in synchronism with the reciprocating movement of the reed, and a stop mechanism, of a pair of switches in an electric circuit controlling said stop mechanism, one of said switches being operated by said cam in its movement to be closed once on each reciprocation of said reed, a support secured to the frame at the rear of said reed, a box rigidly mounted on said support, to be positioned above the loom warp shed rearwardly of said reed, a weft feeler pivotally mounted at its rear end on said box and projecting forwardly from said box exteriorly of said shed and passing through a space between the teeth of .said reed, said feeler having a length s-uflicient to extend through said space throughout the whole reciprocatory movement of said reed, and to maintain the forward end thereof in engagement with the fell of the previously woven fabric, a lever fixed to the other end of said feeler to swing with said feeler about its pivot, the other of said switches comprising two electric contacts, one of which is fixed to said lever within said box and the other of which is fixed in said box, spring means constant- 1y urging said'forward end of said feeler downwardly, said I feeler being so disposed that said contacts remain open,

when the forward end of said feeler is pivoted upwardly by engagement with a weft thread that is being beaten into the fell of the fabric by said reed, and being closed, when the said forward end of said feeler moves downwardly beneath the upper surface of the fabric due to absence of a properly beaten weft thread, said two switches, when both are closed, actuating said stop mechanism, and means mounted on said box for limiting downward pivotal movement of said feeler.

2. The combination claimed in claim 1, including means mounting said support on the loom frame outside the warp threads to be adjustable angularly in a vertical last-inserted weft thread so that said point of contact is adjacent the point of formation of the fabric.

References Cited UNITED STATES PATENTS 1,975,747 10/1934 Hewton 139-37O 2,819,737 1/1958 Opletal 138-370 3,049,152 8/1962 Batty et al 139370 3,289,709 12/1966 Llado 13937O 3,145,739 8/1964 Metzler 139-37O 3,237,656 3/1966 Haupt 139-370 X MERVIN STEIN, Primary Examiner.

plane to control the contact point of said feeler with the 1 JAMES KEE Assistant Emitting/-

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