US2592126A

US2592126A - Electric weft detecting system for shifting shuttle box looms

Info

Publication number: US2592126A
Application number: US131380A
Authority: US
Inventors: Robert A Donnan
Original assignee: Crompton and Knowles Corp
Current assignee: Crompton and Knowles Corp
Priority date: 1949-12-06
Filing date: 1949-12-06
Publication date: 1952-04-08
Anticipated expiration: 1969-04-08

Description

2 SHEETSSHEET 1 R. A. DONNAN ELECTRIC WEFT DETECTING SYSTEM FOR SHIFTING SHUTTLE BOX LOOMS April 8, 1952 Filed Dec. 6, 1949 ATTORNEY N 3 M 1D R N o w -8 0 0 2 m D mm 2 E A V \nm N T T N. II R M a u S V w l a n I ll 9. T ll O a n w g n R IW n v IPMFM w APrll 8, 1952 R. A. DONNAN 2,592,126

ELECTRIC WEFT DETECTING SYSTEM FOR SHIFTING SHUTTLE BOX LOOMS Filed Dec. '6, 1949 2 SHEETS-SHEET 2 FIG] FIGB F|G.9 F|G.|0

FIG." FIGJZ FIGJ?) H614 INVENTOR. ROBERT A.DONNAN ATTORNEY.

Patented Apr. 8, 1952 ELECTRIC DETECTING SYSTEM FOR SHIFTING SHUTTLE BOX LOOMS Robert A. Donnam w'orceste'r Mass, assignor to Crompto'n & Knowles Loom Works, Worcestcr,

Mass a-corporation of Massachusetts Application December 6, 1949, Serial No. 131,380

12'Clainis.

This invention relates-to electrical weft'dtecting systems more particularly for pick "and pick looms having shifting shuttle boxes at-each end thereof and it is the general object of the invention to provide such a system with simple electric circuits connected in such manner'that each weft detector can'be in but one of several branch detector circuits.

The invention relates morep'articularly to that type of weft detectingsystem wherein a'gangof weft detectors is mounted 'in front of the "shifting shuttle boxes at one endof the loom to rise and fall with them so that each weft detector is always in register with'its shuttle box. 'Weft detection "will ordinarily occur when the lay is on itslfront center position during the interval in the loom .cycle in which the shuttle boxes can shift.

Looms of the type to which the'invention'relates are ordinarily provided with .patternichains which control shuttle fbox shifting'levers o'rthe like which move to shifta-selected shuttle box'to active position. The box shifting levers ordinarily start their motions at the beginning of the aforesaid box shifting interval when the lay 'is approximately at bottom center and continue moving throughout the interval until the lay.

reaches approximately top centerposition. 'The levers are therefore moving, if required to move, prior to the detecting period occurrin'gw'hen' the lay is on front center. 7

It is an important object of the j'present'invention to provide each detector with a branch detecting circuit connectable 'to an operating or control circuit by switch means which are positioned by the box shiftingflevers prior "to the detecting period, thereby selecting the branch detecting circuit corresponding to the shuttle next to be active before the weft detectorshave their detecting operations. This result is accomplished by switches which are'moved by the box lifting levers to their selected positions early in the box shifting interval.

Certain weft detecting systems of the general type set forth herein have been usedin the past but have had the defect that the weft detectors could be in series with each other so that if three of four shuttles being detected were depleted of weft the loom would be stopped despite the fact that the shuttle in action carried ample weft. It is another important object-of the present invention to connect one side of each of the weft detecting circuits to a common wire in the system, thereby preventing the detectors from being in series with each other, and having the box shifting lever controlled switches so operated that only one detectingcircuit'can be completed through the operatingcircuit .at the time Of weft detection.

{It is another objectof the present invention to operate the aforesaid switchmeans through-friction devices associated with the box shifting levers in such manner that 'after the switches have been-moved to'their selectedpositionsprior to "detectionbythedete'ctors the box shifting --levers can continue'their motions-to complete the shift of the shuttle boxes. The=box shifting levers, being positively driven by theloom, are'able to overcome the resistance offered by the friction deviceswhether moving to raise or effect lowering'of the shuttle boxes.

If "a b'oxshifter lever'remains inthe same position'for several picksthe aforesaid frictiondevicesmig'ht slip enough to'open a contact. It is a further 'object'of the invention to provide holding means positioned by the levers to prevent slipping of'the friction devices.

With these and other objects in view which will appear as the description proceeds, the invention' resides in "the combination and arrangement of parts hereinafter describedand's'et forth.

In the accompanying drawings, wherein "a convenient embodiment of the inventionis-set forth,

'Fig. 1 is a front elevationof the well-known Knowles head mechanism "for operating the shuttle boxes'in a fancy loom and showin'gthe switches forming'part of the invention,

Fig. 2 is an enlarged vertical section-on line 22, Fig. 1,

Figs; 3 and "4 arediagra'mmatic views looking in the directions of arrows '3 and l -respectively, Fig. 2,

Fig. '5 is a-diagrammatic view in front-elevation'of the lay and shuttleboxes-of a loo'm utilizing the invention showing a gang of'electric weft detectors at theleft'end thereof,

Fig. 6 is a diagramof the electric circuits -used with the invention,

Figs. 7 to 10 are diagrammatic viewsshowing the relative positions of the boxshifting levers,

Figs. '11 to 14 "represent four successive positions of "the switch means controlled *by the box shifting levers, and

Fig. "15 is an enlarged front elevation looking in the direction of arrow 15, Fig. 2, showing the holding'means-for one of the friction devices.

Referring particularly to Fig.5, the loom la-y Ill mounted on lay swords H is provided at its right end with a igang 'RG of shifting shuttle boxesmounted'on'the box lifter rod 12 and at its left end with another gang of shifting shuttle boxes LG having in the "present instance four shuttle boxes I-IV mounted on a box lifter rod l3. The gang EU is moved vertically'with respect to the layby a box lifter chain 14 andin similar manner the left gang LG'is'moved by a box lifter chain Hi.

'The well known Knowles head mech'ani'sm'K. which controls chains 1'4 and '15, includes upper and lower cylinder gears 20 and '21 between which are located vibrator gears one of which is shown at 22. Gear 22 is mounted on a vibrator lever 23 the vertical position of which is determined by a pattern chain 24. Gear 22 operates a relatively short connector 25 attached to the upper end of a box lifter lever 26 the lower end of which is pivoted as at 21 for rocking movement with respect to the mechanism K. A longer connector 30 attached to and operated by a second vibrator gear 3| having its own vibrator lever is attached to the upper end of a box lifting lever 32 pivoted as at 33 intermediate its ends for rocking movement with respect to the mechanism K. The lower end of lever 32 has rotatably mounted thereon a sprocket 34.

Chain l for gang LG is attached as at 35 to lifter lever 26 and is trained around the sprocket 34 and then leads to the left over a guide pulley 36 and thence downwardly for connection to the box gang LG, see Fig. 1. The other chain H has similar operating levers and connections to position the gang RG, but these connections are omitted from the drawings.

Referring to the diagrammatic views 7-10, when the

levers

26 and 32 are in the position shown in Fig. 7, the same as shown in Fig. 1, shuttle box I will be in the active position shown in Fig. 5. When lever 26 is rocked to the left while lever 32 remains unchanged, Fig. 8, box II will be in active position. When lever 26 is to the right and lever 32 is rocked to the position shown in Fig. 9, shuttle box 111 will be in active position, and when the two levers are in the positions indicated in Fig. shuttle box IV will be in active position.

It is to be understood that the pattern chain 24 determines the vertical position of the vibrator gears 22 and 3| and therefore control the positions of the

levers

26 and 32. Furthermore,

levers

26 and 32 are each moved positively in both directions by their vibrator gears. The cylinder gears 20 and 2| are usually set so that they produce turning of the vibrator gears during a box shifting interval starting ordinarily when the lay I0 is on bottom center position and extending through the front center position thereof to the top center position, at which time the selected shuttle box will be in active picking position. The lay l0 swings backwardly and forwardly in usual manner, being on front center at a point in the loom cycle intermediate the start and finish of the box shifting interval.

The loom is provided with a detector carrier 40 which rises and falls with the shuttle box LG and has mounted thereon detectors Dl-D4 which are of the electrical type. These detectors are so mounted that they detect the condition of weft in their respective shuttle boxes I-IV during a detecting period when the lay is at or near front center position, the carrier 40 shifting vertically but not partaking of the back and forth motion of the gang LG. The detectors DI-D4 may be considered collectively a detector gang DG the position of which is controlled by the pattern chain 24 in the same manner that the latter determines the vertical position of the gang LG.

The matter thus far described is of well-known construction and of itself forms no part of the present invention.

In carrying the present invention into effect provision is made for enabling the box lifter levers to select the detector of the gang DG corresponding to the shuttle box next to be in active position prior to the detecting period, and then 4 stopping the loom in the event that a. selected detector indicates weft exhaustion.

In carrying the invention into effect I provide a support secured as at 46 to some part of the loom frame, such as the arch 41. This plate has extending through the lower part thereof a pin 48 which is preferably held in fixed longitudinal position by a set screw 49 threaded into the lower part of support 45, see Fig. 2. The upper left hand, or forward part of support 45 as viewed in Fig. 2 has secured thereto a block of insulatin material 50 which has mounted thereon for movement relatively thereto flexible or resilient electric switch blades or prongs 5| and

contacts

52 and 53. Pivotally mounted on pin 48 is a switch operating lever 55 attached by a connector rod 56 to lever 32. as at 51. When lever 32 rocks back and forth lever 55 rocks with it. A flat plate 60 made preferably of insulating friction material, such as hard fiber, is located between arm or lever 55 and a washer 6| secured to support 45. A compression spring 62 interposed between a collar 63 on pin 48 and lever 55 urges the latter and plate 66 against the washer 6|. A pin 65 secured to lever 55 extends through a slot 66 in plate 60, see Fig. 15.

Lever 55 will be in the full line position shown in Fig. 3 when either of shuttle boxes I or II is active, and the upper part or operating arm 10 of friction plate 60 will be to the right to connect one of the two electrically connected prongs 5| with contact 52. Motion of arm 10 to the right is limited by a stop pin H on support 45 passing through a hole I2 in arm 10 having a diameter much larger than that of pin 1 I. Arm 10 moves from the full line position to the dotted line position, Fig. 3, when either of shuttle boxes III or IV is to be active, and connects one of the prongs 5| with contact 53. Stop pin II also limits motion of arm 10 to the left. The electrical connection of one or the other of prongs 5| with

contact

52 or 53 occurs during the first part of the rocking of lever 32 before the lay reaches front center position and before the weft detectors can perform their weft detecting operations. Thereafter the friction plate 60 slips relatively to lever 55 to permit continued motion of lever 32 to complete shifting of gang LG.

If lever 32 should remain in the position shown in Fig. l for several picks there would be the possibility that friction plate 60 might slip enough relatively to lever 55 to permit right hand prong 5|, Fig. 3, to move away from contact 52. In order to prevent this slipping pin 65 will be moved to the left end of slot 66 in friction plate 60 when lever 32 moves to the position shown in Fig. 1, and since it is a characteristic of the Knowles head that the box lifter levers are locked by action of the corresponding vibrator lever, vibrator gear and connector, friction plate 66 will also be locked by pin 65 against movement toward a neutral position in which prong means 5| would be out of engagement with contact 52. Lock pin 65 will be at the right end of slot 66 when lever 55 has been moved to the dotted line position, Fig. 3, thereby preventing slipping of plate 60 toward a neutral position.

Support 45 has secured to the back thereof a second block 15 of insulation which supports resilient prong members 16 and TI mechanically connected together by an insulating collar 18. These prong members are for engagement respectively with contacts 19 and 80. Other prong members BI and 82 mechanically connected tosolenoid.

assua e gether by anrinsulating collarm are adapted for engagement with :contacts :84 sand "85, respectively. Prong members I6 and 8I ."are "electrically connectedtogether as by connector 96, Fig. 4, to form .in effect a singleprong :designated diagrammaticallyat PI .inFig. 6, while the prong members 1 1 and '82- are electrically :connected by connector 91 to form in effect a single prong member designated diagrammatically rat sP2 in Fig. 6.

The prong members=shownin Fig. .4 have their positions determined by lever 99 *rockably mounted on the rear part aof pin48, .see Fig.2, and positioned by a :connector rod 91 attached as at 92 to the box lifter leveri26. .Aifriction plate 93 of insulation .material similarto :plate 69 .is located between lever .99 and washer .94 secured tosupport45, and acompressionspring 95 similar to .spring 62 is interposed between lever 99 and collar :96 on pin 4:8. The-construction and operation ofpplate .93 :and lever :99 :is similar to the construction and operation "already described in connection with :theprevious description of lever .55 and,plate 69. An upwardly extending arm '91 of plate 93 is formed with a hole 98 through which the rear part of stop pin II extends. A pin 99-on lever .99 extends through a slot I99 in friction plate 93 similar to slot 66 in plate :69 andfor the same purpose.

When lever 99 is in the position shown in full lines in Fig. 4 prong members I6 and I1, corresponding respectively to prong elements PI .and P2, Fig. 6, are electrically connected to contacts I9 and 89, respectively. When box lever 26 shifts arm 9Imoves .to the leftto the dotted line position thereof to cause contact members BI and 82, corresponding also toprongs PI and P2, respectively, Fig. 6, to engage contacts .84 and .85, respectively, at .the same time enabling contacts i9 and 99 to be .disengaged from their corresponding prong members.

The shift of .arm 91 .from the full line .tothe dotted line position .shown'inFig. 4 occurs during the first part of the box shifting interval and is completed before the .lay reaches front center, the lever .99 thereafter sliding with respect to plate .93.

It .will thus be seen that the shift .in position of the switches shown in Figs. 3 and 4, when they occur, will occur prior to thetimeiin a box shifting interval when the weft detectors detect the condition of weft in the shuttle boxes vI-IV. These switches, shown at 5|, .PI and .P2 .in Fig. 6, are collectively designated asswitchmeans S.

Referring particularly to .Fig. .6, the electric circuit means used with the invention includes a transformer T, .a solenoid I9I which when energized either effects immediate stoppage of the loom, or sets..mechanism not shown herein but well understood to effect loom stoppage, and preferably though not necessarily a relay 192 controlled by the weft detectors .and effective when energized to cause energization of the The electric weft detectors are each made with two detecting fingers 195 .and I96 mounted in a base I91 made of electric insulation material. Each pair of :fingers is adapted .for en- .gagement with a ferrule I98 -.of a bobbin .being detected if thebobbin is depleted of weft. When ample weft is present the ferrule will be covered and the two fingers .195 and I96 will ,:be kept insulated from each other during the detecting period. When exhaustion of weft .occurs in any of $118 shuttle ;;boxes the :detector fingers .of the corresponding detector iwill FbB "electrically connectedibya ferrule 198.

!As .shown in Fig. :6, .the .right :hand detector fingers I .of the detectors .'DI .D4 ;are electricallyzconnected by wires I11, 112, .I I3 .and 114, respectively, "to a grounded wire -'I I9. .I-he detector :zfingers I96 .of :the detectors .DI-D4 are connected .aby wires 115, H6, 11 If! :and .I I8, 1TB- spectively, to :contacts .219, 84, Hand 85,..respectively.

;.In :describing :the ;operation 1.01 the :invention it may be assumed that gang LG :has been in some position .other than that shown in Fig. 5 and indication-has :been given by pattern chain 24 to move shuttle .box I 'to active position. This indication will :be followed by such f-movementspf one or the-other, :or both, .of the two box levers 2.6 which =-will move them to the positions shown .in :Figs. .1 :and 7,but before .such movement is :completed the prongs .5! and PI and P2will be in the position shown in Fig. 6 prior to the weft detecting period, iand'switch meanss will be asrshown inFig. .11. If, as the lay heats .up, weft .:is depleted in shuttle .box .I the'following circuit will :be completed: transformer 'T, wire I29, shipper handle control switch SS, wire 'I2I, relay I92, wire I22, prong or switch 5I, contact 52, prong or switch PI, contact 19, wire :5, detector "finger I96, uncovered ilferrule .198 in vshuttle box -I, detector finger I95,=wire II I, wire 71119 "to the ground, and up :from the ground through :wire I23 back to the other side .of the transformer. "When this circuit is completed the :relay is energized and electric conducting :armatures I25 :and 126 of .therelay will .movetto the left from the position shown inFig. :6, whereupon a holding circuit is .established through the relay as follows: From the transformer through the relay to wire 122, contact 121, :armature I25, and wire I28 "to ground. When this circuit is established the relay is maintained energized and is thereafter independent of detector SDI At the same time that the holding circuit is closed-armature I26 engages contact 139, where- 'uponath'e solenoid circuit will be closed and current will flow from the transformer to wire I'2-I, through wire I3I, solenoid I91, wire I32, armazture 1.26, contact I39, and wire -I 33 to the ground. This establishes conditions which bring about stoppage fof' the'loom and opening of the shipper rh'andle :control switch SS, the opening of which breaks the holding circuit to deenergize the relay and permit the armatures I25 and 126 to return to their :normal positions shown in Fig. 6.

It will be apparent from Fig. '6 thatwhendetector DI is in the selected :branch detecting circuit the other detectors will be disconnected from switch "5| and they will notbeable to give indication of weft exhaustion even though they should engage uncovered ferrules I98 in their respective shuttle boxes. It will also be apparent that since the detectors-all have one of their detecting fingers connected to the wire II'9 it is .notpossible for them to become connected in a series circuit to give a false indication and effect unnecessary loom stoppage.

"If shuttle .box II is to move to active position the prongs PI and P2 will be shifted to engage contacts '84 and 95, seeFig. 1'2, respectively, but there will be :no shift of prong 5|,

.hence the .lowest detector D4 :cannot be con- ;nectedzto :wire I22.

If shuttle box .111 .is to be active prong 5| will shift into engagement with contact 53, see Fig. 13, thereby preventing connection of either the detectors D| or D2 with wire I22, and the prongs PI and P2 will be in the position shown in Fig. 6 so that the detector contact 80 corresponding to detector D3 will be electrically connected to prong PI and thence through prong 5| to the wire I22. Also, if shuttle box IV is active a circuit will be completed through detector D4, contact 85, prong P2, contact 53 and prong 5|. In no instance will it be possible to have more than one detector conne'ctible to wire I22 at a time.

The prongs 5|, PI and P2, being moved to positions corresponding to the next shuttle box to be active prior to the detecting period, permits the use of the relatively simple circuit shown in Fig. 6, without the use of holding relays or other electrical equipment, because of the fact that the prongs forming part of the switch mechanism S move to positions corresponding to the shuttle box next to be active prior to the detecting period.

Fig. 6 shows both a solenoid and a relay, but it is to be understood that the invention is not necessarily limited in its use to a relay, inasmuch as the relay can be replaced by the solenoid, and a holding circuit used or omitted, as desired.

From the foregoing it will be seen that the invention sets forth simple electric means by which the box shifting levers 26 and 32 act during the first half of a box shifting interval to move, or maintain, the prongs 5|, PI and P2 in positions corresponding to the detector associated with the shuttle box next to be active before weft detection occurs. In order to assure retention of the prongs or prong members shown in Figs. 3 and 4 in their selected position, the compression springs 62 and 95 may be made as strong as desired and there will be ample power derivable from the positively moved box shifting levers 26 and 32 to overcome any frictional resistance to movement of

levers

55 and 86 with respect to their friction plates. The friction plates 68 and 93 and their

springs

62 and 92 constitute yielding means or connections opera'tively relating the box lifter levers to the switch means and enable the lifter levers during the first part of their movements which shift the shuttle boxes to move the switches. The prongs PI and P2 cooperate with two pairs of detector contacts one of these pairs comprising contacts 19 and 84 associated with the upper pair of detectors, Fig. 6, while switch P2 is associated with

detector contacts

80 and 85 for the lower pair of detectors. The prongs PI and P2 are capable of engagement with but one contact of each pair of detector contacts at a time, and the prong 5| is engageable with but one of the

contacts

52 or 53 at a time to determine which pair of detector contacts shall be capable of completing the circuit. Furthermore, the

pins

65 and 99 hold the

friction plates

60 and 93 from moving away from their selected positions due to vibration of the loom should the box shifting levers remain stationary for several successive picks of the loom. The primary blade 5| and its

primary contacts

52 and 53 may be considered a primary selector switch means or control PC positioned by box lever 32, and the secondary blades PI and P2 and their

secondary contacts

19, 80, 84 and 85 may be considered a secondary selector switch means or control SC positioned by box lever 26, see Fig. 6. The two switch means PC and SC collectively form the previously mentioned selector switch means S.

Having thus described the invention it will be seen that changes and modifications of the foregoing specific disclosure may be made without departing from the spirit and scope of the invention.

What is claimed as new is:

1. In an electric weft detecting system for a loom having a lay provided with a gang of four shuttle boxes which move relatively to the lay during a box shifting interval, mechanism controlling the movements of said gang during said interval including two levers which by their movements determine which shuttle box of the gang shall be in active position at the end of a shifting interval, an electric weft detector having two electrodes for each shuttle box performing a detecting operation during a detecting period occurring during a box shifting interval, electric circuit means effective when closed to cause loom stoppage including one of the electrodes of each detector, said one electrodes being connected to the circuit means in parallel, selector electric switch means, and yielding connections operatively relating the selector switch means to said levers by which the latter move the switch means during the first part only of said movements of the levers to electrically connect the other electrode of the detector corresponding to the shuttle box to be in active position at the end of a box shifting interval to said circuit means prior to the detecting period occurring in said interval, the detector corresponding to the shuttle box to be in active position, if indicating weft exhaustion, closing said circuit means during the detecting period.

2. In an electric weft detecting system for a loom having a lay provided with a gang of shuttle boxes which move relatively to the lay during a box shifting interval, mechanism controlling the movements of said gang during said interval including two levers each having movements to two positions and determinin which shuttle box of the gang shall be in active position at the end of a shifting interval, an electric weft detector for each shuttle box detecting weft in the latter during a detecting period occurring between the start and finish of each shifting interval, provided a weft supply is in the corresponding shuttle box, each detector having two electrodes, electric circuit means including a common conductor effective when closed to cause loom stoppage, one electrode of each detector being connected to said common conductor, a selector contact for each detector, each selector contact being electrically connected to the other electrode of the corresponding detector, selector switch means, and yielding means operatively connecting the selector switch means to said levers causing the latter during the first part only of said movements thereof to move the selector switch means prior to a detecting period to electrically connect to said circuit means the selector contact corresponding to the shuttle box to be in active position at the end of the shifting interval during which the detecting period occurs, said circuit means being closed during the detecting period, provided the detector corresponding to the shuttle box to be in active position at the end of the shifting interval indicates weft exhaustion.

3; In an, electric: weft detectingsystem, for; a loom? having; a lay provided: with. a gang-of: four shuttlee boxes:- which i move relativelyv to. the; lay during aabox shifting: interval; mechanism controlling the movements of said gang during :said intervals: including" two levers each movable to two positions and? determining which. shuttle box of the gang" shall: be in, active" position at the end of a boxshifting interval, an electric weft, detector: for each shuttle box having'two electrodes, the" detectors capable of indicating weft exhaustion during: a detecting; period occurring during: a: box shifting interval, electric circuit means including a common conductor effectivewhenclosed to cause a change inloom operation,- oneelectrode of'each: detector being connected to said common conductor, two. primary selector contacts corresponding to one of said levers, four: secondary selectorcontactscorresponding to the other lever, one secondary contact for each shuttle boxrconnectedelectrically to theother electrode of" the corresponding detector, and: primary and secondary electric switch. meanscontrolled by said one'lever and: by'saidother lever, respectively; electrically connecting the secondary contact correspondingto; the shuttlexboxto" bein' active position at the end of a shifting interval to said circuit means through a primary contact prior to" the detecting periodflthe detector, corresponding to:

the shuttle boxnext to be in active position, if indicating weft exhaustion; closing said: circuitmeans.

4; In an electric weft detecting systemiora looms having a lay: provided with at gang of shuttle boxes which moverelatively'to' the lay during a box shifting interval starting when the lay-is approximately on bottom: center-and ending, when the lay is" approximately on top center, mechanism controlling the movements of said gang during said interval and: including twolevers each movable to two positions and: determining which: shuttle box of the: gang shall be'in active position: at the end of a. box

shifting: interval, an electric weft detector for each shuttle box having twoelectrodes, each detectorcapable ofhaving a detecting: operation during: adetecting: periodi occurring: when the-lay; is-substantially'on front center, electric circuit-'meanseffective, when closed to cause loom stoppage includingone of" the electrodes of 'each detector,, said one electrodes being connected in parallel-to the circuit means, aselector: contactgfor-each detector'electrically. connected to the; other electrode, of the detector, selector electric switch means, and yieldingmeans operatively connecting: the selector switchmeans to said' levers-causing the latter of move said selector switch means between a bottom centerposition'ofithe layand'the detecting period" of at box shifting interval: to connect to said circuitmeansthe: selector contact corresponding. to; the: shuttle; box to; bevin: active position at; theend of the box" shifting interval, the detector corresponding. to" said: shuttle box tobeein; active: position, it indicating weft ,1 exhaustion during; the? detecting period, closing said electric circuit means through thesel'ector contact corresponding to said shuttle box to be in activezposition:

5; Inaanelectric weft; detecting system, for a loom having a lay provided withlavgangof-four shuttle: boxes which move: relatively to'the: lay during, a box shifting:v interval, mechanismcom box'shiitingrr interval including two levers each movableduringr abox shifting interval to two positions to: move the; gang; and determining which shuttle; box of the gang shall be in active position. at the endof'a shifting interval, an electric: weft? detector having two electrodes for each: shuttleboxcapable of indicating weft exhaustiorr irrthe corresponding shuttle box durtrolling; thez'movements of said; gang-Iduring-Jsaid ing adetecting: period occuring subsequent to the: start of each box-shifting interval, provided a: weft supply is in the corresponding shuttle box; electriccircuit means effective when closed to cause a change in loom operation and includingone of the-electrodes of' each of the detectors, the latter electrodes being connected to said circuit means in parallel, primary electric switch means operatedbyone of said levers and including two primary selector contacts, secondary selector switch means operated by the other lever" including foursecondary selector contacts, one-for each shuttle box and the corresponding detector; each secondary contact being electrically connected to the other electrodeof the corresponding detector, and means operated: by said levers" electrically connecting the secondary selector contact corresponding to theshuttle box to: be in active position-at the end: of ashifting interval to said electric circuit means through one or the other of said primary contacts prior tothe detecting period of the box shifting interval, whereby the detector corresponding to. the shuttle box to be in. active position at the end of the interval, if indicating weft exhaustion, closes said electric circuit means.

6; Inian electric weft detecting system for a loomshaving a lay provided with a gang of shuttle' boxes which move with respect to the lay during a box shifting interval, mechanism includingtwo box lifter levers having movements during a. boxv shifting; interval to move said gangrelatively to the layand determine which shuttle box'shall be in active position at the end of a'shifting interval, electric circuit means effective-when closedto causeloom stoppage, the circuit means including branch detector circuits connected inparallel thereto, one branch circuit for each shuttle-box,v an electric weft detector having two electrodes for each shuttle box and-branch circuit capable of having a detecting;operation-during; a detecting period occurring during each box shifting interval, each branch detector circuit including the electrodes of theassociateddetector'and a selector contact, selector electric switch means, and yielding: means operatively connecting the selector switchlmeans to said levers and effective during'the first partof said movements of the latter to cause said levers to'move the selector ,switchmeans during a box shifting interval prior to the-corresponding detecting period to connect tosaidelectric circuit means the selector contact and associated branch detector circuit corresponding to theshuttle box to be in: active position at the end, of the shifting interval; the detector corresponding to the shuttle box to be in active position, if indicating weft exhaustion, completing said electric circuit means.

7. In an electric. weft detecting system for a loom having a lay provided with a gang of shuttle boxes-movablerelatively to the lay duringa box shiftinginterval mechanism includeration relative to the associated shuttle box during a detecting period occurring after the 'start of a box shifting interval, electric circuit means effective upon closure to stop the loom, the circuit means including one of the electrodes of each detector, selector contacts, one for each detector, connected electrically to the other electrode of the corresponding detector, selector electric switch means including a switch for each lever, and operative connections between each lever and the corresponding switch means effective during a shifting interval prior to the detecting period corresponding thereto to connect the selector contact corresponding to the shuttle box to be in active position at the end of the shifting interval to said circuit means, to the end that the electric weft detector corresponding to the shuttle to be in active position at the end of a shifting interval,

if indicating weft exhaustion, will close said electric circuit means.

8. In an electric weft detecting system for a loom having a lay provided with a gang of four shuttle boxes which move relatively to the lay during a box shifting interval, mechanism including two levers operatively connected to said gang movable during a box shifting interval to move the gang relatively to the lay, the levers by the positions thereof at the end of a box shifting interval determining which shuttle box of the gang shall be in active position, an electric weft detector having two electrodes for each shuttle box capable of having a detecting operation in the corresponding shuttle box during a detecting period occurring after the start of a box shifting interval, electric circuit means effective when closed to stop the loom, one of the electrodes of each detector being connected to said electric circuit means, a pair of primary selector contacts, primary electric switch means to connect either of said primary contacts to said electric circuit means, four secondary selector contacts, one for each detector electrically connected to the other electrode of the corresponding detector, secondary electric switch means including two blades, one blade capable of connecting one primary contact to either of two secondary contacts and the other blade capable of connecting the other primary contact to either of the other two secondary contacts, and operative connections between one of said levers and the primary switch and other operative connections between the other lever and the secondary switch effective during a box shifting interval prior to the corresponding detecting period to connect the secondary selector contact corresponding to the shuttle box to be in active position at the end of the box shifting interval to the primary selector contact correspond-- ing to the shuttle box to be in said active position, to the end that the electric weft detector corresponding to said shuttle box to be in active position, if indicating weft exhaustion, will complete said electric circuit means through the secondary and primary contacts corresponding to said shuttle box to be in active position.

9. In an electric weft detecting system for a loom having a lay provided with a gang of four shifting shuttle boxes movable relatively thereto during a box shifting interval, mechanism including two levers each capable of being moved positively to either of two positions by said mechanism throughout a box shifting interval, said levers effecting shifting of the shuttle boxes and determining which of the latter shall be in active position at the end of a box shifting interval, an electric weft detector having two electrodes for each shuttle box capable of indicating weft exhaustion during a detecting period occurring in each shifting interval, electric circuit means effective when closed to cause a change in loom operation, one electrode for each detector being permanently connected to said electric circuit means, primary selector switch means including two primary selector contacts, secondary selector switch means including four secondary selector contacts, one secondary contact electrically connected to the other electrode of each detector, friction operative connections between one of said levers and the primary selector switch means, and other friction operative connections between the other lever and the secondary selector switch means, said friction operative connections effective to cause said levers when moving during the first part of a box shifting interval to connect a primary selector contact and a secondary selector contact corresponding to the shuttle box to be in active position at the end of the shifting interval to said electric circuit means prior to said detecting period, said levers continuing to move during the remainder of the box shifting interval subsequent to the detecting period and said friction operative connections yielding to permit said continued movement of the levers, whereby the electric weft detector corresponding to the shuttle box in the active position at the end of a shifting interval, if indicating weft exhaustion, completes said electric circuit means.

10. In an electric weft detecting system for a loom having a lay provided with two shuttle boxes movable relatively thereto during a box shifting interval starting before and continuing after the lay reaches front center position in the loom cycle, shuttle box shifting mechanism including a box lifter lever operatively connected to the shuttle boxes and determining which of the latter is to be in active position at the end of a shifting interval, electric weft detecting means including a detector for each shuttle box performing a detecting operation when the lay is substantially on front center, electric circuit means effective when closed to cause a change in loom operation and including the detector means and selector electric contacts, one for each shuttle box, the open and closed condition of which is to be determined prior to the time the lay reaches front center during a box shifting interval, a contact controlling lever operatively connected to the box lifter lever and moved by the latter throughout a box shifting interval, friction means controlling the opening and closing of said contacts frictionally engaging the operating lever but capable of slipping relatively thereto, and stop means for the friction means, the box lifter lever when shifting during a box shifting interval moving the contact controlling lever and causing the latter by reason of frictional engagement with the friction means to deter- 'mine the open and closed condition of the contacts prior to the time the lay reaches front center, the stop means arresting further movement of the friction means and the operating 11. In an electrical weft detecting system for a loom having two shuttle boxes movable relatively to the lay during a box shifting interval starting before and continuing after the lay is on front center position in the loom cycle, mechanism including abox lifter lever effecting shifting of the shuttle boxes during said interval and moving throughout the latter and determining which shuttle box shall be in active position at the end of said interval, electric switch means including two contacts, one for each shuttle box, the open and closed condition of which is to be determined for any shifting interval prior to the time the lay reaches front center in the interval, a switch operating lever operatively connected to the lifter lever, and electric switch closing means operatively connected frictionally to the operating lever and effective during a part of the box shifting interval prior to the time the lay is on front center to close the contact corresponding to the shuttle box to be in active position at the end of the interval and thereafter slip relatively to the operating lever as the latter continues to move during the remainder of the box shifting interval.

12. In an electrical weft detecting system for a loom having two shuttle boxes movable rela- 30 the interval operatively connected to the shuttle boxes and moving throughout said interval to shift the shuttle boxes relatively to the lay, a support fixed with respect to the loom, a pair of spaced electric contacts on said support insulated therefrom, one for each shuttle box, the open and closed condition of said contacts for any given shifting interval to be determined during the interval prior to the time the lay reaches front center, an operating lever pivoted on said support operatively connected to the lifter lever and moved by the latter throughout the box shifting interval, and a friction plate frictionally engaging the operating lever and moved by the latter to close the contact corresponding to the shuttle box to be in active position at the end of the interval during that part of the box shifting interval prior to the time the lay is on front center and slipping relatively to the operating lever during the remainder of the shifting interval.

ROBERT A. DONNAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,834,360 Wakefield .4 Dec. 1, 1931 2,049,584 Gordon Aug. 4, 1936 2,485,134 Bergstrom Oct. 18, 1949