US1573942A

US1573942A - Automatic weft-replenishing loom

Info

Publication number: US1573942A
Application number: US746725A
Authority: US
Inventors: Hollins Denis Machell
Original assignee: Draper Corp
Current assignee: Draper Corp
Priority date: 1924-10-30
Filing date: 1924-10-30
Publication date: 1926-02-23
Anticipated expiration: 1943-02-23

Description

, Feb. 23 1926. 1,573,942

D. M. HOLLINS AUTOMATIC WEFT REPLENISHING LOOM Filed Oct. 30, 1924 4 Sheets-Sheet 1 \nvenTor.

Denis M.H0Hins Feb. 23 1926. 1,573,942

- D. M. HOLLINS AUTOMATIC WEFT REPLENISHING LOOM Filed OCt. 50, 1924 4 Sheets-Sheet 2 lnvenTor.

, Denis M.HOH'|ns M MkW Afiys.

Feb. 23 1926.

D. M. HOl LIN$ AUTOMATIC WEFT REPLENISHING LOOM Filed Oct. 30 1924 4 Sheets-Sheet 3 fly. 5.

lnveni 'or. Denis M. Hollins jay. 4.

byMQI/MJ W 1,573,942 D. M. HOLLINS AUTOMATIC WEFT REPLENISHING LOOM Filed Oct. 30, 1924 4 Sheets-Sheet 4 \nnani'or. Denis M- 0! i Aflys.

Patented F eb. 23, 1925.

renn n *IDENIS MACHELL I-IOLLI'NSQGI" BLACKBURN ENGLAND, ASSIG-NOR/ TO DRAPEBA COB- PORATION, OF HOPEDALE, "MASSACHUSETTS, A CORPO'BATION 033 IMAIIEE.

AUTOMATIC VJEFT-BEPLENIEEHING LOOW'I.

i Application filed October 30,192 .SeriaLNo. 746,725.

. To all whom it may concern:

' Be it known that I, DENIS MAoHnLL Honrmsasubject of King George V of Great Britain, residing at Blackburn, in the county otLancaster, England, have invented a new .,.;;.nd useful Improvement in Automatic VettlteplenishingLooms, of which the "following is a specification.

My invention relating to looms -for weaving has reference to looms provided with means to detect substantial exhaustion of plenishing loom -to which the invention has reference is that in which there are provided, ,at one end of the lay, two movable shuttle boxes adapted to receive shuttles containing Nwefts of diiferent colours or characters,

' .with :means to present either of said shuttle 2 -boxes opposite the raceway 111 accordance with the indicationsot a box pattern surface,

and at the other end of the lay a single tixed' shuttle box.

Theobject of the invention is to provide improved means-whereliiy, on detection of substantial exhaustion o1 the weft in a shuttle whichfor the time being is active, a new bobbin of'appropriate colour or character willbe: supplied to-such shuttlethe first. time it returns to the replenishing end of the loom consequent upon such detection. It may be that the exhausted shuttle, when detection ot substantial exhaustion occurs is indicated by the box pattern surface to remain-active, in which case the transfer takes placeon the second pick following de- 1 tection, that is to say when the shuttle has been picked. from the detecting and rcplcnishing end of the loom to the change box end and back again. It may be. however, that .when the shuttle returns to the change box end, onithe pick following upon that on which detection of exhaustion occurred. the .boxpatternwill call for a change or shuttles, and in such case it is necessary to delay the transfer actionuntil the shuttle in which substantial exhaustion was detectedis again called upon to become active and is re- .turned to the replenishing end of the loom. The mechanism constituting the invention provides therefore, that when, consequent upon. detection of substantial exhaustion oi weft. in a shuttle, said shuttle becomes inactive, a registration is made of the detection and the transfer action is held up until the shuttle again becomes active, whoreupon the first time the shuttle returns to the replenishing end of the loom the replenishment is effected.

The characteristic feature of the invention is that the energizingof a single solenoid is rendered cllective to initiate transfer of a new bobbin to either of the two shuttles and, in case of a shuttle going out of action following upon detection of substantial exhaustion of weft therein, the solenoid is instrumental in registering such detection and delaying the replenishment until the shuttle again becomes active.

In the accompanying drawings Fig. 1 is a plan view of the mechanism constituting the invention;

2 is an end view of part of the mcchanism looking in the direction of the arrow A, Fig. 1;

Fig. 8 is a side elevation looking in the direction of the arrow B, F 1;

Fig. i is an elevation looking in lhe direction of the arrow C, Fig. 3, of the selector switch. forming part of the mechanism;

Fig. 5 is an elevation looking in thedirection of the arrow 1), Fig. 3, of the trigger locl: forming part of the mechanism:

Fig; (i is a detail plan view hereinafter referred to;

Figs. 7 and 8 are diagrams illustrating the electric circuits set up during the action of the mechanism; and

Figs. 9 and 10 illustrate details referred to later.

For the purposes of the invention the loom organization includes a magazine having two compartments to hold bobbins of the two colours of weft, such magazine being mounted over the fixed shuttle box and be ing arranged to oscillate or move in synchronism with the movements of" the shifting shuttle boxes to present over a shuttle. when it is positioned in the lixed shuttle box, a bobbin containing woit of the correct colour or character. Associated with the magazine is a transfer hammer adapted to be operated at the appropriate time to engage the new bobbin and force it downwardly into the shuttle in exchange for the exhausted bob-- detecting beat, to ascertain the OOIlClYtlOIl of the weft supply, .such feeler being of the type designed to close an electric circuit by reason of contact with a metallic sleeve on the bobbin, when said sleeve becomes uncovered by exhaustion of the weft to a predetermined point.

These parts just referred to, namely the magazineoscillating in synchronism with the movements of the shifting shuttle boxes, the transfer hammer and its actuating means, and the weft feeler, do not in themselves form any part of the invention and are well known in the art. I have not. therefore, deemed it necessary to show them in the drawings,with the exception of the weft feeler which is shown diagrammatically in Figs. 7 and 8 for the purpose of enabling the electric circuits set up to be understood.

The present invention relates to automatic filling replenishing mechanism, for shifting shuttle-box looms of the character above described, comprising an electric circuit having a feeler branch with a feeler therein and transfer branches corresponding to the magazine's containing weft carriers to be delivered to the respective shuttles, with a selector switch operable by the box-shifting mechanism to select the transfer branch corresponding to the active or running shuttle, and a single solenoid common to all of said branches operable when momentarily energized by detection of e:; haustion of filling upon the weft carrier of the active shuttle to condition and to complete the selected transfer branch of the electric circuit and also to initiate the action of the transferring mechanism.

Referring now to the mechanism constituting the invention illustrated herein, this comprises a box or casing 1 adapted to be secured on the loom frame preferably at the shifting shuttle box end of the loom, and

having mounted within it a solenoid 2 provided with a core or plunger 3. The solenoid 2 is connected to contacts l and 5 to which current is led from a suitable source of supply by means of a contact plug 6.

The contact plug 6 also leads current to 7 two other contacts 7 and 8 which are adapted to be connected either with a contact 9 or a contact 10, these latter contacts being connected respectively with the

insulated plates

11 and 12 carrying respectively the contacts 13 and 14.

The connection of the contacts 7 and 8 with the contact 9 or the contact 10 is effected by means of a selector switch comp ising a segmental plate 15 carried by a block 16 mounted loosely on a shaft 17 journalled in

bushes

18, 18 carried by the casing 1. A stud 19 on an arm 20, fast upon the shaft 17, extends through an opening in the block 16 so that as the shaft 17 is rocked in one or the other direction the plate 15 will engage either the contact 9 or the contact 10. A lever 20 fast upon the shaft 17 is suitably connected with the shifting shuttle box operating mechanism in such manner that the said lever and shaft 17 are rocked, in synchronism with the movements of the two shifting shuttle boxes, to connect up either the contact 9 or the contact 10 when one or the other shuttle boX is brought into line with the raceway.

Pivotally mounted upon a spindle 21 carried by a bracket 22 are the bosses of two trigger levers 23 and as carrying

respective contacts

23 and 24 adapted to engage the contacts 13 and 14.

Springs

25 and 26 coiled about the bosses of the respective trigger levers tend to rotate the said levers in a direction to carry the

contacts

23 and 24 into engagement with the contacts, and a retaining bar 27, carried by a spring pressed plate 28 pivotally mounted at 28, acts to engage the portions 23 and 24: of the trigger levers and hold their contacts out of engagement with the contacts 13 and 14:.

The plunger 3 of the solenoid 2 passes through an opening 28 in the plate 28, and has at its upper end a conical or tapered portion 3. Pivotally mounted at 29 on the plate 28-is a flat plate 29 acted upon by a spring 30 to hold it normally against a stop 31 as shown in full lines in Fig. 6. Downward movement of the plunger 3 causes the lower larger end of the conical portion 3 to engage the edge of the plate 29 and, consequently, to rock the plate 28 downwardly, thus removing the retaining bar 27 from operative position with respect to the portion 23 and 24- of the trigger levers. As the plate 28 swings about its pivot, as it is moved downwardly, the edge of the plate 29 is carried clear of the lower end of the portion 3 of the plunger, so that the latter may continue its downward movement and the plate 28, with the plate 29, be returned to normal position, for a purpose which will be afterwardsmade clear. As the plunger 3 rises again the face of the tapered portion 3 bears against the edge of the plate 29 and swings it out of the way, as shown in dotted lines in Fig. 6, so that the plunger can return to its normal raised position.

Fast upon' the shaft 17 is the boss of a segmental locking member 32 having the flanged portion 32 provided-with a central notch 32 This lockingmember co-operates with the tapered end portions '23 and 24 of the trigger levers as will 'after wards appear, and rocks with the shaft 17 to present the notch 32 opposite either the trigger lever 23 or the lever 24 synchronously with the movements offthe shifting shuttle boxes. It should be observed that the tapered end portions of the trigger levers are insulated from the levers by blocks 23, 24E, of insulating material.

' Fast upon a shaft 33 journalled in openings in the casing 1 is an arm 34: having a pin 34 which extends through a slot 35 in the lower end of a member 35. This member 35 extends up through a slot 32 in the flange 32 of the locking member 32 and I hasits upper end bent forwardly and down ward-1y as at 35 This member 35 is provided for the purpose of returning the triggerlevers 23 and2 l to normal position after they have operated to effect transfer of a new bobbin to their corresponding shuttle as will afterwards appear. Actuation of the member 35 is effected by means of an arm 33 fast on the shaft33 and adapted to be. en-

.gaged by an abutment '36 carried by the usual trip lever 37 by means of which the usual changing motion shaft-38 1s operated .to position the transfer dog when a transfer tioned in the path of the tripper heel.

T0 effect the positioning of the trip lever,

a lever 39; pivoted at'39 in the casing 1 is provided. r One end 39 of this'lever extends beneath the lower end of the plunger 3 of vthe solenoid 2, whilst the other e1id39 extends "beneath the trip lever 37. It follows,

therefore, that as the; plunger 3 is attracted :and drawn downwardly, by the. energizing of .the-solenoid=2, the triplever will be raised and its rear end placed into a posi- .tion to be engaged by the tripper heel as the .latter moves forwardly.- The action of the trip lever and tripper heel will be understood from Figs. 9 and lOwvherein' lO represents the tripper heehtl the usual lever pivotally mounted at 4-2 and carrying said tripper 'h-eel,and 43 the usual cam operating on the lever ll to causethe tripper heel to move forwardly every second pick, such forv taming bar to release the trigger levers,

ward movement being timed to occur as a shuttle is being picked towards the replenishing end of the loom, so that by the time "the shuttle arrives beneath the magazine the transfer; dog will have been raised into operative position for engagement by the bunter on the lay as the latter beats up.

lever Fig. 9 shows in dotted lines the trippcr heel in forward position when the trip lever has not been raised, and Fig. 10 shows the similar position when the trip lever has been raised and has consequently been moved to effect a transfer. The trip lever and tripper heel device for effecting positioning of the transfer dog are well known in the art and form no part of the invention.

The action of the mechanisms above de scribed is as follows Immediately the weft feeler blades make contact with the metal sleeve of a substantially exhausted bobbin B, the feeler branch of the circuit is set up including the tl'eelcr' F, the solenoid 2 and source of supply G, and a switch S conveniently disposed on the loom. This circuit is illustrated in Fig. 7.

The energizing of the solenoid 2 consequent upon the completion of the circuit just referred to causes the retaining bar 27 to be moved clear of the portions 23 and 2-? of the trigger levers 23 and 2% and the trigger lever concerned is moved pivotally by its spring to engage its respective con tact 13 or l t thus conditioningone of the transfer branches of the electric circuit. The

contact

9 or 10 corresponding to the box for the time being in action being at this time closed by the selector switch, a transfer branch circuit is set up including the solenoid 2, the trigger lever concerned, the corresponding contact 9 or ltl, the selector switch, the source of supply G and the loom switch S as shown in Fig. 8.

Let it be assumed that the upper of the two shifting shuttle boxes is in action. The

selector switch will at this time have closed the contact 9; the notch 32 of the locking member 32 will be positioned opposite the end 23 of the trigger lever 23; and the magazine will be positioned to present beneath the transfer hammer a bobbin contain- 111g weft of a colour or character corresponding to that in the active shuttle.

I If the weft feelernow detects substantial exhaustion of weft in the active shuttle, the feeler branch of the circuit is completed as above described and the movement of the retaining bar 27 consequent upon the energizing of the solenoid 2, releases the trigger The lever 2-l correspondingto the shifting shuttle box not in action 'annot move by reason of its end 2% being positioned beneath the solid. portion of thclocking flange 32'. The downward movement of the plunger 3, after having moved the repermits said retaining barto rise agaln as previously described, thus enabling the retaining bar to assume its position of control with respect to the trigger lever 21-. This is necessary for the reason afterwards mentioned.

The release, ofthe trigger lever 23 causes one of the contacts 23 toengage the contact 9 and the transfer circuit corresponding to the active shuttle is thus set up including the solenoid, the trigger lever 23, the contact 9 and the source of supply.

The energizing of the solenoid 2 and the consequent depression of the plunger 3 as a result of the detention or" weft exhaustion and the completion of the circuits above described, causes the end 39 of the lever 39 to attempt to raise the trip lever. At the moment of detection, the tripper heel is in forward position and the rear end of the trip lever cannot rise. 7

As soon, however, as the tripper heel com licences to move rearwardly, that is to say as the shuttle is picked back to the change box end on the pick following detection, the rear end of the trip lever is freed and the lever 39 acts to raise said lever, so that its rear end is in a position to be engaged by the I tripper heel as the latter makes it next forward movement.

It the box pattern mechanism indicates that the same shuttle, in which exhaustion has been detected, is to remain active, the parts remain in the positions above described,

with the result that as the exhausted shuttle is being returned to the replenishing end of the loom the trip lever is operated and when the shuttle arrives back at the replenishing end thetransfer ot the new bobbin is effect ed. The forward movement of the trip lever by the tripper heel, to initiate the transfer, causes the abutn1ent36 on the trip lever to engage the arm 33 and rock the shaft 33, thus moving downwardly the member 35 and causing its upper end to engage the end 23 of the trigger lever 23 and return said lever to normal position with its portion 23 engaged behind the retaining bar 27, thus breaking the selected branch of the electric circuit and leaving the mechanism ready for another detecting action of the feeler.

It may be, however, that as the shuttleot the upper box, exhaustion of the weft in which it is assumed has been detected, returns to the change box end on the pick following the detection, the box pattern mechanism may call for the boxes to change. If this occurs, the movement of the selector switch,

' synchronously with the change of boxes, cuts out the contact 9 and breaks the circuit of the selected branch through the trigger lever 23, the locking member 32 swinging over simultaneously with the selector switch and removing the notch to a position over the end 24 of the other trigger lever 24. The trigger lever 23, corresponding to the upper shuttle box, exhaustion of the weft in the shuttle of which has been detected, remains however in the position to which it has been moved, that is to say with its contact 23 resting on the contact 9 and with its end 23 above the locking flange 32. The remaining of the trigger lever 23 in this position, which may be termed the position of registration or in position to condition the branch of the electric circuit, ensures that the first time the upper shuttle box again becomes active, its shuttle will have its weft supply replenished as will be seen presently.

It will be remembered that the des ent of the plunger 3, consequent upon the energizing of the solenoid by completion of the first circuit when the detection of exhaustion occurred, released the trigger lever 23 and then permitted the retaining bar to move back to operative position. The object of permitting the retaining bar to so move back is that it the return of the retaining bar were delayed until the ascent of the plunger 3 it might be that the notch 32 of the locking device was presented above the end of the lever 24 before the plunger had risen sutiiciently far to permit the retaining bar to operate, in which case the trigger lever 2a would be permitted to move to the position of registration without being called for.

The swinging over of the locking member 32 with the change 01": boxes carries over also, as will be understood, the resetting lever or member 35 and positions it over the end of the trigger lever 24.

The de-energizing oi": the solenoid consequent upon the breaking of the circuit as above mentioned permits the trip lever to drop again, so that it will not be engaged by the tripper heel as the lattercomes forward.

The boxes having changed, the shuttle of the lower box continues to operate as long as may be called for, and may in its turn become exhausted during its period of activity in which case its bobbin will be changed in the manner above described, the trigger 24 being released and the second circuit being formed through same, the trigger lever 23 of the upper shuttle box remaining meanwhile in the position of registration, thus conditioning the circuit so that when the selector switch is moved to complete the circuit of this branch the solenoid will at once be energized.

When, therefore, the upper shuttle box becomes active again, the original second circuit is again completed, the trip lever is raised to initiate the action of the transferring mechanism so that when the exhausted shuttle of the upper box arrives again for the first time at the replenishing end of the loom it receives its new bobbin. 3

It will be understood that exhaustion may have been detected in one shuttle and that thereafter said shuttle may have become inactive and that exhaustion may be detected in the other shuttle on the pick on which the latter is callednpon to go out of action. in such case both trigger levers will be in.

a position of registration at one time, and both transfer circuits will be conditioned, but the transfer will be effected to the shuttle which is again con'iinq into action, leaving the trigger-lever of the second shuttle in the position of registration and its transfer branch ,in conditioned relation until such time as, in its turn, such second shuttle again becomes active.

Having thus described my invention, wnat I claim as new and desire to secure by Letters Patent is 1. Automatic weft replenishing mechanism for shifting shuttle-box looms comprising an electric circuit having a feeler branch with a feeler therein and transfer branches corresponding to the magazines con-- tainingiweft carriers to be delivered to the respective shuttles, a selector switch operable bythe box-shifting mechanism to select the transfer branch corresponding to the active shuttle, a single solenoid common to all. of said branches operable, when momentarily'energized by detection of exhaus- [ion of "filling upon the weft carrier of the active shuttle, to condition the selectedtransfer branch and means operable upon completion of the circuit through said transfer branch toinitiate theaction of the transferring mechanism.

2. Automatic weft replenishing mechanism for shifting shuttle-box looms comprising an electric circuit having a feeler branch with a feeler therein and transfer branches the Weft carriers to be delivered to the recorresponding to the magazines containing spectiveshuttles, a selector switch operable by the box-shifting mechanism to select the transfer branch corresponding to the active shuttle and a single solenoid common to all of said branches operable,.when m0mentari- 1y energized by detection of exhaustionot filling upon the weft carrier of the active "shuttle, to condition the selected transfer 'branch so as to cause the actuation of the transfer branch corresponding to the active shuttleand a single solenoid common to all of said branches operable,- when momentari 1y energized by detection of exhaustion of fillingupon .the weft carrier of the active shuttle, to COIlClltlO'll t l1 selected transfer branch and also to initiate the action of the transferring mechanism and for maintaining the selected branch in meat tioned relation to effect a completion of transfer upon return of said shuttle to active position if said shuttle is rendered inactive by reason of a change of shuttles occurring upon the picl: following detection of such exhaustion.

l. Automatic weft replenishing mecha nism-for shifting shuttle box looms comprising an electric circuit having a feeler branch with a feeler therein and transfer branchescorresponding to the magazines containing the weft carriers to be delivered to the respective shuttles, a selector switch operable by the box-shifting mechanism to select the transfer branch corresponding to the active shuttle, a single solenoid common to all of said branches operable, when momentarily energized. by detection of exhaustion of filling upon the weft carrier of the active shuttie, to condition the selected transfer branch and also to initiate the action of the transferring mechaninsm and means operable to break a circuit through the selected branch, after initiation of the action of the transferring mechanism has been accomplished.

5. Automatic weft replenishing mechanism for shifting shuttle-box looms comprising an electric circuit having a feeler branch with a feeler therein and transfer branches corresponding to the respective magazines containing weft carriers to be delivered to the respective shuttles, a selector switch op erable by the box-shifting mecaanism to select the transfer branch corresponding to the active shuttle, a trigger lever switch in each transfer branch, means normally locking said trigger switches in open POSltlOILQl solenoid common to all of said branches operable, when momentarily energized by detection by the feeler of exhaustion of weft on the weft carrier of the active shuttle to release said trigger switch locking means, thereby closing the trigger lever switch of the selected branc-h'and maintaining the solenoid in energized condition and means operable by the solenoid when thus ei'iergized to initiatethe action of the transferring mechanism.

6. Automatic weft replenishing mechanism for shifting shuttle-box looms comprising an electric circuit having a feeler branch with a feeler therein and transfer branches corresptniding to the respective magazines containing weft carriers to be delivered to the respective shuttles, a selector switch up erable by the bos-shifting mechanism to select the transfer branch corresponding to the active shuttle, a trigger lever switch in each transfer branch, means normally locking said trigger switches in open position, a solenoid common to all of said branches operable, when momentarily energized by detection by the feeler of exhaustion of weft on the weft carrier of the active shuttle to release said trigger switch locking means,

thereby closing the trigger lever switch of the selected branch and maintaining the solenoid in energized condition, means operable by the solenoid when thus energized to initiate the action of the transferring mechanism and means operable by the transfer actuating mechanism to restore the trigger lever to open position after it has operated to initiate the action of the transferring mechanism.

7. Automatic weft replenishing mecha nism for shifting shuttle-box looms comprising an electric circuit having a feelerbranch with a feeler therein and transfer branches corresponding to the respective magazines containing weft carriers to be delivered to the respective shuttles, a selector switch operable by the boxshifting mechanism to select the transfer branch corresponding to the active shuttle, a trigger lever switch in each transfer branch, means normally locking said trigger switches in open position, a solenoid common to all of said branches operable, when momentarily energized by detection by the feeler of exhaustion of weft on the weft carrier of the active shuttle, to release said trigger switch locking means, thereby closing the trigger lever switch of the selected branch and maintaining the solenoid in energized condition, means operable by the solenoid when thus energized to initiate the action of the transferring mechanism and means for preventing restoration of said trigger levers to normal open position until transfer is effected, notwithstanding the actuation of the shuttle-box mechanism to change shuttles on the next pick after detection of exhaustion of filling.

8. Automatic weft replenishing mechanism for shifting shuttle-box looms comprismg an electric circuit having a feeler branch with a feeler therein and transfer branches corresponding to the respective magazines containing weft carriers to be delivered to the respective shuttles, a selector switch operable by the box-shifting mechanism to se lect the branch corresponding to the active shuttle, a trigger'lever switch in. each transfer branch, a pivotally mounted locking member normally engaging said trigger switch levers and retaining the switches in open position, a single solenoid common to all of said branches having its core releasably connected to said locking means and operable when momentarily energized by re tection by the feeler of exhaustion of weft in. the active shuttle to release the locking member from said trigger levers and means operable by the movement of said core to initiate the action of the transferring mechanism.

La /snag 9. Automatic weft replenishing mechanism for shifting shuttle-box looms cone prising an electric circuit having a feeler branch with a feeler therein and transfer branches corresponding to the respective magazines containing weft carriers to be delivered to the respective shuttles, a selector switch operable by the box-shifting mechanism to select the branch corresponding to the. ac ive shuttle, a trigger lever switch in eachtransfer branch, a pivotally mounted locking member normally engaging said trigger switch levers and retaining the switches in open position, a single solenoid common to all of said branches having its core releasably connected to said locking means and operable when momentarily energized by detection by the feeler of exhaustion ofweftin the active shuttle to release the locking member from said trigger levers, supplemental means for locking in open po sition a released trigger lever of a branch corresponding to an inactive shuttle, if such trigger lever has not been previously released as a result of detection of weft eX-j haustion in such shuttle and means operable by the movement of said core to initiate the action of the transferring mechanism.

10. Automatic weft replenishing mechanism for shifting shuttle-box looms comprising an electric circuit having a feeler branch with a feeler therein and transfer branches corresponding to the respective magazines containing weft carriers to be delivered to the respective shuttles, a selector switch operable by the box-shifting mechanism to select the branch corresponding to the active shuttle, a trigger lever switch in each transfer branch, a pivotally mounted locking member normally engaging said trigger switch levers and retaining the switches in open position, a single solenoid common to all of said branches having its core releasably connected to said locking means and operable when momentarily energized by detection by the feeler of exhaustion of weft in the active shuttle to release the locking member from said trigger levers, a sector, movable in synchronism with the movon'ient of the box-shifting mechanism.

DENIS MACHELL HOLLINS.