US3536105A - Looms - Google Patents

Description

United States Patent [72] Inventor Mario Piccoli 24025 Gazzaniga, Bergamo, Italy [21] Appl. No. 836,198 [22] Filed June 11,1969

Continuation of Ser. No. 670,619, Sept. 26, 1967, abandoned.

[56] References Cited UNITED STATES PATENTS 3,237,656 3/1966 l-laupt 139/122 3,276,482 10/1966 Liebchen 139/122 3,439,715 4/1969 Juillard 139/122 Primary ExaminerHenry S. J audon Attorney Young and Thompson ABSTRACT: A device for presenting weft yarns in continuous supply weft yarn looms having a hook lever for gripping and retaining the selected weft yarn swingably mounted on the loom sley and controlled by a cam and a second hook lever for retaining all the weft yarns swingably mounted on the fixed part of the loom and controlled by a second cam and for severing the selected weft yarn. The first and second hook levers coact to return an unsevered length of the selected weft yarn i to the group of unselected weft yarns retained by the second hook lever. I

Sheet In venlor Mme/a P/cc'au la M ribw Attorneys LOOMS This is a continuation of application Ser. No. 670,619, filed Sept. 26, 1967, and now abandoned.

BACKGROUND OF THE INVENTION This invention relates to a weft yarn presentation device in continuous weft supply looms.

It is known that in continuous weft supply looms, wherein weft yarns are gripped at an end of the warp shed by a gripper or similar means carrying them to the middle of the shed where a second gripper in turn grips them to carry the same at the other end of the shed, selection and presentation devices are provided for weft yarns of a different colour, material and/or count, cooperating in making up the fabric. It is also known that these selection devices comprise a plurality of rods terminating in an eyelet at the free end thereof, a given weft yarn sliding within the eyelet of each rod. The rods are arranged to move one or more at a time from an inoperative position to an operative position (under the mechanical, or preferably electromechanical, control of punched board programming devices: Jaquard or Vincenzi systems), whereby the weft yarn or yarns carried thereby can be engaged by the device for presenting the weft yarn or yarns to the carrier gripper for the yarns of the loom.

As is known, presentation devices generally comprise a yarn gripping lever, means for retaining the gripped yarn at a position suitable for presentation to the gripper and subsequent displacement of said yarn as caused by the gripper, and a feeler for controlling the yarn continuity.

In heretofore known devices. the engagement and disengagement of weft yarns by said retaining means were always SUMMARY OF THE INVENTION These disadvantages are now fully overcome by the improved presentation device according to the present invention, said device being of the type comprising a first gripping and retaining hook lever for the weft yarn as selected by the selecting device, a feeler, and a second retaining hook lever for all the weft yarns, and characterized in that said first lever and feeler are swingably mounted upstream of the warp shed, on the sley, while said second lever is swingably mounted on the fixed part of the loom, still upstream of the warp shed, but closer thereto than the first lever and feeler, said levers being oscillated by earns the rotation of which is controlled by the general mechanism for the loom. BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be disclosed in detail according to a preferred embodiment thereof, given merely by way of example and shown in the accompanying drawings, in which:

FIG. 1 is a perspective view of some portions of the loom as seen from the selecting device, with portions cut away and other portions broken away and the position and paths of the carriers shown by broken arrows when a weft thread is drawn across the path of one of the carriers for presentation to that one carrier; and

FIG. 2 is a view similar to that of FIG. 1, as seen from the median portion of the loom.

DESCRIPTION OF THE PREFERRED EMBODIMENT Loom l, to which the device according to the invention is applied, is fitted with a selecting device 2 having levers 3, within eyelets 4 of which weft yarns 5 slide from suitably braked supply cops or bobbins. In FIG. 2, only one of selecting levers 3, has been operated to place its weft yarn 5,, at the disposal of the loom presentation means, and therefore at the disposal of the carrier gripper of the loom.

The improved presentation means according to the invention comprise a first hook lever 6 swingably mounted on sley 7 of loom l; a feeler 8 in side by side relationship to saidlever 6, and a second hook lever 9 acting also as a knife and swingably mounted on the fixed part of the loom l opposite lever 6 and feeler 8, but slightly nearer than the latter to the warp shed. Oscillation of lever 6 is controlled by a cam 10 rotated by the general mechanism of the loom through a suitable drive. Cam 10 engages cam follower ll of a rocking lever 12 controlling said hook lever 6 through two connecting rods l3, l5 and a second rocking lever 14.

Oscillation of hook lever 9 is similarly controlled by a cam l6carried by the same shaft as cam 10 and engaging a cam follower 17 of a toggle lever 18 directly operating on hook lever 9.

The profile of cam 10 is of a such a design that hook lever 6 will lower to grip the already selected yarn 5 prior to passage of the first carrier gripper of the loom past the point where said gripper should grip said yarn and will rise again to release the'jweft yarn when the end of the latter is about to be released by the other loom gripper at the opposite out let of the shed. In turn, the profile of cam 16 is such that hook lever 9 will rise to release the weft yarns just after the entry of the grippers into the warp shed and will be lowered to grip again all the weft yarns upon the grippers reexiting from the shed and while the sley is moving to tighten the weft yam introduced into the fabric.

Under these circumstances, the operation of the device is apparent: once selecting lever 3,, has pushed a weft yarn 5,, into gripping position, the hook lever 6 will lower, gripping said yarn 5,, and arranging it at a suitable position for being gripped by the gripper which, cutting the yarn on the knife side of book 9, drags it into the shed and exchanges it with the other gripper until the yarn is released from said second gripper at the opposite end of the shed. The knife side of hook 9 is of course its upstream side with respect to the direction of weft yarn travel toward the warp shed. While such release occurs, hook lever 6 will rise and between said selecting lever 3,, and shed entry said yarn 5,, will take on a straight stretched condition without being any more caused to retain the angled position shown in FIG. 2 and taken on after cutting and raising of lever 9. When sley 7 moves and tightens the just inserted weft yarn against the already manufactured fabric, said yarn will be therefore accurately stretched at its supply end and, as pushed by the sley action, will unfailingly join the other weft yarns inside of said hook of lever 9, the latter having lowered in the meantime, for being retained therein. In the subsequent steps, upon operation of the selecting levers the selected yarns are caused to take on the initial position.

Feeler 8 is held at a lowered position by said weft yarn 5,,, which depresses feeler 8 for all the period during which said hook lever 6 is lowered. Should the yarn break, the feeler will be released and on rising will stop the loom motor feed, causing this motor and the loom to be stopped.

As readily inferred from the above operation description, the improved device according to the invention avoids to the highest degree a frequent and detrimental drawback which is a distinctive feature of known devices. In fact, the possibility exists with the latter that the weft yarn would be unstretched at its supply end after being inserted in the warp and thus it may occur that it will not be gripped by the hook lever 9 and remain therefore at a position liable to be gripped by the lever 6 at the next cycle, even when this is not intended thus mixing with the selected weft yarn. This drawback of known devices results from the fact that yarn restraint (positively effected by lever 6 in this invention) was effected by a member fixed to the sley, which member released the yarn only after releasing of the driving end of said yarn, through the tightening movement of the sley.

In addition to preventing weft yarns from being incorrectly supplied, which usually results in their being undesirably mixed, or from giving rise to machine jammings, the device according to this invention also makes it possible to limit the braking torque exerted on weft supply cops or bobbins over the devices according to the prior art, wherein braking was also used for partially reducing the above drawback.

lt should be noted thatthe braking reduction for the wefi yarns enables a substantial increase in the loom speed with the v obvious advantages resulting therefrom'sLooms fitted with the a device according to thevinvention willbe,-. therefore, faster, more reliable, and more "continuous [when running and will permit emanufacturing of higher quality fabrics. v i

I claim: a g 1. In a loom having a I frame and a lay including a reed through which warp threads pass which are formed intosuc- 1 cessive sheds which converge toward a fell andhaving a-plubetween said first and second hooksin said retracted lay position-thereby to present said selected thread to said one carrier.

' said one carrier: thereafter engaging isclected thread between said first and second hooks and drawing said selected .thread about said second hook'to sever the selected thread and carrying said selected thread aim the shed with said O selected thread guided by said first hook between said one carrier and saidassociated selector.

rality of different weftthreads extending fromgsaidlfe'll to a l plurality of stationary supply means the lay-having guide means thereon defining apath for a 'pairof carriers one of whichcngages aweftithread ata point adjacent an edge of the warp in the shedding area and carriesit intothe'shed to'a point plurality of weft threadsclectors on the loom through each-of which a different iweft thread passes between said supply 7 'means and the fell; the improvementlcomprising a first hook i mounted on said layii to grasp a weft thread whichhas been selected by the associated said selector, at a point between said selected thread into the fell. 1

g 2;. A loom as claimed in claim 1, whejreinsaid means for Irnoving said first hookare operative to raise said first hook out 'ofengagement with said selectedth read b'e fore the lay beats 3. A loom as claimed in claim :1, wherein said means for "moving said second hook are operative to raise said second hook out of the path of said selected thread before the lay be atssaidselected thread into the fell.

A loom as claimed in claim-l,and a feelermounte'd on the lay closely adjacent thefirst hook andlying in the path of and being depressable by thatpor tion of a ;weft thread which is ont-he sideof said first hook opposite said selectors, said feeler 3 upon rising in response to a weft thread break being operable to stop the loom; i i l '5. A loom as claimed in claim 1, said meansfor moving said first hook relative to thelay comprising means for lowering saidfirst hook to grip said selected thread immediately after selection thereof and for maintaining said first hook lowered said associated selector andthe fell, a second hookmount ed 1 ward position of said lay-to grasp said selected thread ata 1 point between saidassociated selector and the second hook v and to draw said selected thread back across said carrier path assaidv lay moves from a forward positiontoward a retracted position'with said selected thread crossing said carrier path Ion the frame on the side of said path which is opposite the 're'ed xiit said retracted lay 'position,lmeans to move said 1" second hook relative to said frame to grasp said selected" thread at'a point between said associatedselector, and the fell, and means to move said firsthookr'elative to said lay in a for? .1

to guide said selected thread until the latter iscomplet'ely in- Sorted in the shed. t 1

i 1 q 6. A loom as claimed in claim I, said meansfor moving said second hook relative to the frame comprising means to raise said second hook out of the path of said selected thread before thetlay beats said selected thread into the fell and for lowering said second hook again into a position to? grasp a weft thread to be subsequently sclectcd.- upon movement of the lay toward the fell after thcfirst-mentioned selected thread has passed said second hook.

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