US2609010A - Electric protection means for looms - Google Patents

Description

Sept. 2, 1952- w. A. BLANCHARD ELECTRIC PROTECTION MEANS FOR LOOMS 2 SHEETSFSHEET 1 Filed April 3, 1950 #40 INVENTOR wlLLlAM A. BLANQHARD m FIGA ATTORNEY Sept. 2, 1952 w. A. BLANCHARD 2,609,010

ELECTRIC PROTECTION MEANS F'OR LOOMS Filed April 5, 1950 2 SHEETS-SHEET 2 INVENTOR B2 WILLIAM A .BLANCHARD A TTORNEY Patented Sept. 2, 1952 UNITED .STATES PATENT O FF ICE ELECTRIC PROTECTION MEANS VFOR LOOMS Blanchard, Millbury, .Mass., .assigner `to Crompton & Knowles LoomWorks, `Worcester, ,.Mass., `a corporation `.of .Massachusetts Application April 3, 1950, Serial No. 153,676

This invention relates to improvements in electric .'fprotecti'onlmeans for llooms fof y.the type in which the vshuttle if :running `properly :gives indicatonfof .timely` arrival at va :given point *along the flay .andi Y#thereby 4permits fcontinued loom operation.

Ituhas been :proposed heretofore to equip a loom with 2a type of :electric `protection -utilizing a switch located falong :the lay between vthe shuttle. fboxes Lto have `its condition :changed by the shuttle. The .switch "is "part v:of :an :electric circuit `.and if the sshuttlechanges .theswitch atfa given time .in'theill'oom :cycle :the :loom continues' to operate, but-'rif :the: fswitchcisnot changed at the given time the circuit controls stopping means to -eiect-iprompt .stoppage :oi the-"loom,

"In fast Yrunning .'rl'ooms the :shuttle operated.

switchwillibelclosed for only-.a very :brief -interval audit .is desirable to. provide some iorm. zof lock. which. will .hold the switch momentarily in. `the position to-whichit ismioved by theshuttle :after the latter passes zthe iswitch. .Such a lock will also. permitv continued loom operation if the shuttle should reach the switchearlier than normal.` -A lock for :this purposel is shown `for in.- stance `in :coi-pending application VSerial No. 134,001, filed Decemberpp1949 by Moss. Itis necessary Vof *course` yto restore the switch to its normal conditioneachbeatofthe ,loom` in .order thatfeachight of ethe. shuttle. may 'be detected, and this can :be .done in simple manner by .a stop `or `the like .on thev loom frameto 'releasexthe' lock `as fthe lay approaches iront. center. p yUnder Asome l conditions fof operation. it :is desirahle-:tohave two -shuttleoperatedswitches ar:- ranged in detecting zones spaced-fromfeach other along the lay between the: shuttle boxesfso `.that the shuttle will .give indication `of ,presence Lat aV poi-nt- `between `the longitudinal center of Vthe lay and theshuttle box vtoward which zit is traveling.; When-.two switches nare used both ofA them will ordinarily be .closed by a single flight of the shuttle and whenv .av .switchv lock is used '-.the viirst of the switches lto -be `closed willhe temporarily locked .and will not returnto normalscondition untilthe layrapproachescfront center. `The sec--v ond switch. isnot closed ,untilsome time later in'A the loom cycle 7andit-is this secondlswitch 4which isreled upon todetermine `whether `or not -the shuttle is running on time. Ifrthereforerclosure of. .the iirst switch` V shouldloe able towcauseA a ,change .oi energizatiorr of. the loom controlling electromagnetic device, .such` `.as `a relayor. r.a solenoid, the operation of the .second switch. will. be without effect'. f

'In order that two switches may be employed ,14 claims. (01.130-3431l 2 each Shaving alocking `feature 'it' is aan important object of the invention :to arrange the :switches in lseries so that 'even @though `the :first vswitch l'to be :closed lis Llocked 1 momentarily the controlling circuit. cannot be closed .until the .second of zthe switches vis `also closed yby "the shuttle.

Electric `protections lof 'the itype vto uwhich the' invention more particularly 4relates can employ;

either of `-two `loom:controllingmeans. In onezof these :means 4a :mechanical-ly `timed knock-.off mechanism `normally set to stop the :loomcan have `its .condition :changed `eleotromagnetically so that :if 'the :shuttle is running properly the normalsetting will be canceledand the loom'can continue to run. The other Vcontrol means-de pende yupon' continuous energization of a relay which becomes deenergized with resultant loom stoppage if the vshuttle is late.

:Itisfa `further object-oi the invention toiutilize shuttle -operated self-locking switches lin seriesin either of these two loom control systems. When `a normally ndeenergfized solenoid is `utilized to cancel thenorma-lsetting of a mechanical. setting mechanism the two switches are arranged in series with the solenoid. When .continuously energized .relaywis employed the two shuttle switcheswill be in series with eachother .but ina branch `circuitwhich*is in parallel with va ltimer branch circuit.

` The. invention `further relates to improvements.

in the 4mechanism which .enables .the shuttle tooperate .its switch, this mechanism including. preferably a normally stationary tubesecuredtothe `lay to provide a guidefor a switch operatingl plunger-.moved relatively `to the .guide by .the shuttle.

plunger fso. thatthe forcerequired to be exerted by .the shuttle on the plungerto. close .thefswitch may be reducedlzto.aminimum. This adjustmentv valso makes the mechanism adaptable 'to varying.

conditions ,of warp tension.

With ,these andother objects in view which will appear as the descriptionprooeeds, theinvention resides inthe combination -and' arrangementof.`A

partsfhereinafter Vdescribed and. set forth.

ln'the accompanying drawings, wherein two forms Vof the invention areset forth,

rection of arrow 2, Fig. .1,

jFigiBis a vertical section online 3'-3, Fig. 2, showing the switch mechanism in its unlocking rIhe guide .permits .a relative vadjust-- ment between .opposed forces exerted on. the

3 position in full lines and in locked condition in dotted lines,

Fig. 4 is an enlarged detail horizontal section on line 4-4, Fig. 2,

Fig. 5 is an enlarged detailed vertical section on line 5-5, Fig. 3,

Fig. 6 is a diagrammatic view showing the preferred form ofelectric circuit used with the mechanical knock-off,

Fig. 7 is a view similar to Fig. 6 but showing the modified form of electric circuit used withr the continuously energized relay,

Fig. 8 is a diagrammatic plan view of the lay showing the spaced shuttle detecting zones and the plungers which operate the shuttle switches located between the shuttle boxes at the ends of the lay, and

Fig. 9 is a detail side elevation showing part of the structure set forth in Fig. 1 adapted for use with the modified form of the invention.

vReferring particularly to Fig. 1, wherein the preferred form of the invention is shown, a loom frame I supports top and bottom shafts 2 and 3, respectively, which in the present instance are connected by gears 4 and 5 which cause the bottom shaft to turn once for every second pick of the loom or rotation of shaft 2. The lay 5 is reciprocated backwardly and forwardly by connectors one of which is shown at 1 operatedby the top or crank shaft 2. The shipper handle 8 is ofusual form and has a depending arm 9 operatively connected to a rod IIJ extending forwardly from a knock-off mechanism designated generally at II. This mechanism includes a solenoid I2 mounted on a stationary support I3 and controlling a link I4 pivoted at its forward end to a knock-off lever I5. The latter is pivoted at its lower end to a stationary axis I6 which may be carried by the support cr stand I3 and is connected at its upper end as at I1 to the rear end of rod I0.

-An actuator or knock-off lever I8 is pivoted as at I9 to stand I3 and is oscillated every pick of the loom by two oppositely extending cams and 2| secured to the bottom shaft. Ordinarily, the link I4 will be in the path of lever l8- to be moved by the latter to stop the loom, but when solenoid I2 is energized ,it will'act to lift the link out of the path of the lever and as the latter rocks on a working stroke thereof it will miss link I4 and the loom will continue to run. If the solenoid is not energized before lever I8 starts its working stroke link I4 will be moved by the cam to stop the loom. As viewed in Fig. 1 the shipper handle for mechanism 8 is in the non-running position, but will be pulled forward, to the left in Fig. 1, in order to start loom operation. The knock-olf mechanism may be similar to that shown in prior patent to Payne 1,873,465 except that in that patent the link I4 is'normally out of the path of lever` I8.

While the rod I0 has been described as being operatively connected to the handle 8 this is only one way in which forward motion of rod I8 can be utilized to stop the loom. The loom generally has a brake handle which is not shown herein, vand in some instances the rod is connected to the brake handle. It is to be understood however that when rod I8 is moved forwardly from its' normal running position mechanism will be set into operation to'cause prompt loom stoppage. Lever I8 has its working stroke during each forward motion of the lay 6 so that the loom can be stopped at a time in its cycle when the CII 4 lay will be a considerable distance behind front center.

It is to be understood from the matter thus far described that the shuttle S will be picked during rearward motion of the lay at a time when the latter is approximately on its top center position, after which the shuttle will be in flight across thejlay and v'will ordinarily come to rest at the'opposite side of the loom during the ensuing forward motion of the lay. The shuttle passes through the top and bottom warp sheds W I and W2, respectively, while in flight, and if the shuttle is running properly it will pass out of the warp shed while the lay is still some distance from its front center position, but if for any reason the shuttle is running slow it may not be able to get out of the shed in time to prevent a Warp smash as the lay moves toward its front center position. It is under this last condition that the loom must be stopped in order to prevent a warp smash.

B y referring to Fig. 8 it will be seen that the lay beam 35 having a shuttle race 3I has right and let shuttle boxes RB and LB, respectively, the shuttle passing from one shuttle box to the other shuttle box for each revolution of the top shaft 2. The lay has two shuttle detecting zones ZI and Z2 and has right and left switch mechanisms designated generally at RS and LS for the zones ZI and Z2,'respectvely. Each switch mechanism is located an appreciable distance from the adjacent shuttle box. These mechanisms are both alike and a detailed description will be given of but one of them, namely, switch mechanism RS.

Depending from and fixed with respect to the lay 5 is a hanger or support 32 bolted at 33 to the under side of beam 30. The hanger has a switch and plunger carrier 34 secured thereto as at .35, see Fig. 2. lThe shuttle operated switch RS is secured to the carrier 34 as at 36. This switch has a resilient blade 38fastened at its left end, Fig. 3, to a post v39 xed to the body 48 of the switch, which is preferably made of electric insulating material. The switch has a contact or electrode 4I normally spaced below but adapted for engagement with the blade 38.

Switch RS is equipped with a small plunger 43 vertically movable in the body 40 and having a shoulder -44 under an operating arm 45 pivoted as at 46 to the body 40. A spring 41 acts normally to hold the arm 45 in its raised position as shown in full lines in Fig. 3, and the blade 38 is resilient so that under these conditions it holds the small plunger 43 in raised position with its shoulder 44 against the arm'45.

A switch operating plunger 58 is arranged for vertical sliding motion on the lay and has the upper end 5I thereof normally projecting upwardly to a slight extent into the path of the shuttle andvabove the race plate 3l. When the shuttle engages the upper end of the plunger the latter is depressed to move the armv 45 down from the full line position to the dotted line position shown in Fig. 3. This results in downward motion of the small plunger 43 which causes the blade 38 to engage contact 4I to close the switch.

-In order that the shuttle switch RS may be held closed temporarily a lock is provided including a plunger 55 slidable in a forward extension 56 of the switch carrier 34. The plunger 55 is urged rearwardly by a compression spring 51 which surrounds part of a stem 58 extending forwardly from the plunger 55. A collar 59 secured to the forward end of stem 58, Ythe left 'end as viewed inFlgg, `is adapted for engagement with the upper end of a Lrelease lever-60 pivoted'as atfGl to'the'carrier '34; The lower-end of lever BU is adapted -for engagement with a fixed but adjustable stop 62 held in any approved manner on 'the loom frame, as by'a plate 63 depending from the breast beam 64 of the loom. As the lay approaches front lcenter the lever '60 engages stop 62 and is rocked in a counter-clockwise directionvas vviewed in Eig. 3 to pull the plunger E5 forwardly.

r Normally, the lever 45 and plunger 55 are as shown in full lines .in"Fig. 3, vbut 'when vplunger 50 is depressedby theshuttle lever45 rmoves down andthe rear part of'plunger 55 rmoves over it, as shown 'in dotted lines, ".iig.v 3,'to lock the switch closed. This will generallyv occur when the lay isfrearward of its front center position vand resetting or 'release 'lever 60 is behind'stop 62. When Vplunger S55 tis :moved forwardly at :front center, as already described, the switch is unlockedandreturns to'its normal open position.

The shuttle operated plungerll vpasses 'through and is guided by a tube or guide 65 the lower end 'of which is .threadedthrough a lateral .extensionfof the'switch holder carrier 34. INuts 61 'and 68 .are threaded on lto :the Atube Y65 above and below extension :66, respectively, to hold lthe tube in vertically adjusted position Vwith respect to the lay. A. compression spring 'l0 isinterposed between vthe lower end ofthe .tube 65 anda head 1l 'onthe bottom of plunger 50. By varying the vertical pcsition'of vthe guide tube 65 wthrespect to the lay "and vswitch the .downward force exerted byspring lzonthe arm 45 can beadjusted. It .willbe apparent'fromFig. 3that the downward force derived :from spring T0 `is opposed by -a greater `upwardly ydirected force derived from spring 4t1. :Adjustment of sleeve 65"permits variation :of the force exerted by .spring 10, andthe nearer this ifcrce isto the force of spring 41 `the less will be the force required from 'the shuttle to `close switch RS.

As already stated, the twoswitches RSand LS and Ltheir associated parts will `both be .as described partcnlarly .in connection with Fig. 3, and ythe shuttle in :asingle flight across the loom will first Ydepress the vplunger 50 of one of these switch mechanisms and then the other. Each switch when depressed will :be held Vby its lock until the lay reaches front center.

The electric circuit used with 4the Ypreferred form of the invention is shown in Fig. 6; `Considering that. the shuttle is leaving the right box RB and vis traveling across the loom -in a left hand direction fas'viewed in-Fig. 8, the shuttle will first 4pass through 'zonerZl of the -lay and closeswitch-RSshortly after emerging from the shuttle 4boxRlB. It will then continue through the warpished andpass through zone Z2,closing switch LSshortly before entering the left boxLB. When both `of these switches are closed the following loom protection electric circuit will be completed: transformer T, wire 15, switch LS, wire 16,switch RS, wire '11, solenoid l2, and Wire 18 `hack to the transformer. If the vshuttle is running on -timeswitch LS will be -closed and therefore the circuit will be completed to cause solenoid l2 to .lift the link I4 just before theactuator or knock-off lever I8 starts'a working stroke and the -loom will continue to run. If, however, the shuttle should `be late in arriving at switch LS and the latter should still be open when the workingvstroke of lever I8 starts,` the link ,I4 will be. pushed. to :the .left Fies- -1 and. 6, .i0 18589# loom stoppage. LIf'the yshuttleis runnlngtonztimel' the lay will continue to front centerxin'usual mannerandboth switches RS andLSwillfbe Viinlocked so that the circuit of Fig. 6l will be in condition for another protection detecting.'operationv on the next beatfof the loom.

In the modified form of the invention the two branch circuit shown in Fig. 7 is'utilized. During normal `shuttle operation vthis :circuit is normally closed by one or theother-of .its -branclriesfsoatlflat a 'relay 80 will be .continuously energized. relay controls a switch 8| associated with a con-.- trol means C operating preferably electrically to stop the loom motor M, and hence the loom, when relay becomes ldeeriergized and switch'fl opens. The circuit .shown in Fig. 7 includes. a. norm-ally closed timer .switch which Vwillbe sette open` briefly when 'the shuttle passes the second ol lthe vswitches RS vor LS, provided the shuttle is'on timal I '1 'In order to Aeiect this timed opening `of .the switch TS the top shaft 2 as shown in zliig. 9 has a ycam 82 secured thereto .engaging an :arm '83 of the'switch mechanism TS. vThe latter has a blade `.84 which normally engages a contactfor electrodes, see Fig. 7.. At a given time in every one pick cycle of the loom cam 82 `rocks arm'83 and switch'TS will open at a time whenlthe shut.- tle, if running on time, closes the second of the lay carried switches. which it passes :in a night.

Normally, the following timer branch circuit will be closed: .transformer T, wire 86., switch TS'.v wires 81 andSB., relay .80,1and wire89 back `,to the. transformer. vIf the shuttle is running on `time a second or shuttle vdetecting'branch circuit will be closed as follows: transformer 'TL'Wire 86, switch LS, wire 90, Vswitch RS, wires -91 'and'88, relay 80 and wire 89 back tothe transformen Relay '.80 `will therefore remain energized despite opening of switch TS. Should the shuttle he late, however, one of theswitchesyRS or LS will bevopen when switch TS opens and the relay 80 will become deenergized. The `switches RS and LS are `the same as in the :preferred for-m and will 'be connected .in series in the second-or shut.- tle detecting branch circuit just described. It will be understood from Fig. '7 that 'although the two switches RS and LS are connect-ed in series with each other their branch detecting vcircuitis Iin parallel with the timer branch circuit.

VReferring again to a left hand ilight of the shuttle from box RB toward box LB, switch RS Will'be closed early in the shuttle Aflight while 'the timer switch is closed and the switch LS willbe closed later when the timer switch is open, -provided the shuttle is on time. When the shuttle travels in the reverse direction toward box 'RB switch RS will be closed after'switch LS'but during -opening of switch TS, provided the shuttle is on time. l

In the modified form of `the invention the switches RS and LS will be unlocked when the lay reaches front center and will both moveto open position, but at this time the switch TS is closed.

It will be obvious from both Figs. 6 and 7 that if the shuttle operated switches were in'separate `detecting branch cir-cuits in parallel with the tim-er branch then closure of the first shuttle operated switch would energize the electromagnetic device when switch TS opened, and closure off the second .lay carried switch would be `of no effect. In both Figs. 6 .and 7, however, the` switches con` trolled Aby the shuttle are. in series .and .both'musfl be closed and on ytime before 'the loom can con-f' tinue'to run.

In thefoperation of both forms of the invention itis to'cbe understood that the stopping mechanism will act to stop the loom promptly at the time in the loom cycle when the shuttle should have closed both of the lay carri-ed switches, and that this time is earlier in the forward beat of the lay than the point at which the locks for the switches are moved to unlocking position. The lay switches are locked unt-il after the lever I8 has started its working stroke, or until after the timer switch TS closes after being opened by cam 82;

From the foregoing it will be seen that Vthe invention sets forth an electric protection for a loom wherein two shuttle operated switches spaced along the lay may be held in locked position when operated by the shuttle and both switches must be closed by a given time in the loom cycle due to timely arrival of the shuttle at a given point along the length of the lay to permit continued loom operati-on. Both the shuttle operated switches will be opened by forward motion of the lay as the latter yapproaches front center. In both forms of the invention the shuttle operated switches are in series, being in ser-ies with the solenoid l2 in the preferred form of the invention, and bein-g in series in a branch detector circuit which is in parallel to the timer circuit in the modied form of the invention.

It will also be seen that the switches RS an-d LS are so made Ithat a-djustment of the sleeve 65 permits a variation in the forcerequired by the shuttle to effect switch closure.

Having thus described the invention -it will be seen that changes and modications of the foregoing specic disclosure may be made without departing from the spirit and 'scope of the invention.

What is claim-ed as new is:

l. In electric protection means fora loom having a shuttle to travel across a lay, two normally open electric switches located atspaced points along the lay, lock means for each switch operative upon closure or the switch to hold the latter closed, the shuttle in a flight across the lay effecting closure rst of one of said switches and then closure of the other switch, loom stopping means, electric circuit means including switches in series controlling said stopping means and preventing the latter from stopping the loom if the shuttle eilects closure of both of said switches by a given time in the loom cycle, and

means operative subsequent tc said time in the loom cycle to release said lock means to permit said switches to return to normal open position.

2. In electric protection means for a loom having a lay and a shuttle to move across the lay, two normally open electric switches on the lay located at spaced points therealong, lock. means eiective upon closure of either switch to hold the latter closed, the shuttle in a flight across the lay closing first one of said switches and then the other of said switches, loom stopping means, an electro-magnetic device controlling said stopping means, electric circuit means including said switches and said device in series operative to prevent said stopping means from stopping the loom if both of said switches have been closed by the shuttle at a given time in the loom cycle, and means releasing said lock means to eiect opening of said switches at a point in the loom cycle subsequent to said given time.

3. In electric protection means for a loom havsaid ing a shuttle to travel along a layhaving la shuttle box at each end thereof, two normally open electric switches on the lay between'the shuttle boxes, one switch being adjacent to one of said shuttle boxes and the other switch being adjacent to the other shuttle box, the shuttle in a flight across the lay closing rst one of said switches after leaving one of said shuttle boxes and thereafter closing the other switch before reaching the other shuttle box, means holding each switch closed subsequent to closure thereof, stopping means for the loom, an electro-magnetic device controlling said stopping means effective when energized at a given time in the loom cycle to prevent said stoppingv means from stopping the loom, electric circuit means including said switches and said device in series effective if both of said switches have been closed by the shuttle at said given time in the loom cycle to effect energization o f said device at said time, and means' cooperating with said Vholding means to effect opening of said switches subsequent to said given time in the loom cycle and prior to said given time in the next loom cycle.

4. In electric protection means for a loom having a lay across which a shuttle moves, two normally open switches located, at spaced points along the lay, the shuttle in a night across the lay closing rst .one of said switches andthen closing the other switch, lock means operative upon closure of either switch to hold the latter closed, loom stopping means, an electromagnetic device controlling said stopping means elective if deenergized at a given time in the loom cycle to cause the stopping means to stop the loom but effective if energized at said given time to prevent said stopping means from stopping the loom, electric circuit means including said switches and said electromagnetic device in series effective when closed to energize said device, said circuit means being closed only upon closure of both of said switches by the shuttle, and means effecting release of the lock means at a'point in the loomv cycle subsequent to said given time.

5. In electric protection means for a loom having a lay across which a shuttle moves incident to loom operation, two normally open electric switches on the lay located at spaced points therealong, the shuttle when moving along the lay closing rst one of said switches and then the other of said switches, lock means operative upon closure of said switches to hold the latter closed, stopping mechanism for the loom normally set to stop the loom at a given time in the loom cycle, an electromagnetic device controlling said stopping means and eiiective if energized at said time to prevent the stopping means from stopping the loom, electric circuit means including said device and said switches in series, said electric circuit being closed to energize said device at said given time if the shuttle in its movement along the lay effects closure of both of said switches by said given time, and means effecting release of said lock means at a point in th loom cycle subsequent to said given time.

6. In electric protection means for a loom having a lay provided with a shuttle box at each end thereof and in lwhich a shuttle is in ight between said shuttle boxes for a portion of a one-pick cycle of the loom, two normally open electric switches on said lay between said shuttle boxes and spaced along the lay, one switch adjacent to one shuttle box and one switch adjacent tothe other shuttle box, means operative upon closure of either switch to hold the latter closed,ithe

shuttle when :in ,iiightifl `running properly Aeffcctingclosurelcf both. of.,V said switches by the time the. loom ,has reachedza given point in said onevpick cycle,v loom stopping means normally 4operative to initiate loom. stoppage at substantially said` point in the cycle including a cam lever andl a stopping,` element normally in thepath of'tbecam lever, an electromagnetic device. controlling the position of said element, and series electric circuit means including said switches and device effective to energize the latter to move the element out of the path of said cam lever if; the shuttle in its iiight between said shuttle boxes eifects closure of both 4of, said switchesby the time the. loom reaches said point in the cycle thereof.

7. In electric protection means fora loom having a lay provided with a shuttle box at each end thereof and a lshuttle to move from one shuttle box along the lay to the other shuttle box, two normally open electric switchesspaced along thel lay effective when closed to remain closed until the lay reaches a given position in the forward movement thereof, whereupon said switches open if closed, loom stopping means normally operative to initiate loom stoppage at a given time in each one pick cycle of the loom before the lay reaches said given position, an electromagnetic device controlling said stopping means and effective if energized at said given time to prevent said stopping means from stopping the loom, and electric circuit means including said switches and device in series eifective to energize said device if the shuttle while in flight between the shuttle boxes closes both of said switches not later than said time in the loom cycle.

8. In electric protection means for a loom having a lay provided with two detecting zones spaced along the length thereof and a shuttle which when traveling in one direction along the lay passes through one zone and then the other zone, the shuttle when traveling in the opposite direction passing first through said other zone and then through said one zone, the shuttle when running correctly on any flight thereof passing through the second zone through which it passes not later than a given time in the loom cycle, a normally open electric switch located at each zone eiective when closed to remain closed until the lay reaches a given position in the forward movement thereof subsequent to said given time, whereupon said switch opens, loom stopping means normally operative to stop the loom at said given time in the loom cycle, electromagnetic means controlling said stopping means and effective if energized at said given time to prevent the stopping means from stopping the loom, and electric circuit means including said switches and said electromagnetic means in series energizing the latter and thereupon preventing the stop means from stopping the loom provided the shuttle has closed both of said switches not later than said given time in the loom cycle.

9. In electric protection means for a loom having a lay and a shuttle to move thereacross, two normally open electric switches on the lay located at spaced points along the length thereof, each switch when closed remaining closed until the lay reaches a given point in the forward movement thereof in the cycle of the loom, whereupon the switch opens, an electromagnetic device, stopping means dependent upon continued energization of said device to permit continued operation of the loom, said stopping means effective upon deenergization of the device to causeloom stoppage, a branch electric circuit including said device normally closed but open at a given' time inthe loomcyclevprior to arrival of the vlay at said point in the forward movement thereof,.and other electric branch circuit means including` said switches in series, said other branch circuit being in parallel with therst branch. circuit` means and effective to continue energization ofr said electromagnetic device if the shuttle in its flight across the lay has closed both of said switches by said given time inthe .loom cycle. i l

10. In electric loom protection for a, loom having a lay and a shuttle to travel thereacross, two normally open. electric switches located at spaced 'points along the lay, each switch Awhen closedv remaining closed until the lay reaches a given point in the forward movement thereof, whereupon the` switch opens, an electromagnetic device, vloomfstopping means controlled by said device effective when the latter is energized to permit continued loom operation and effective when the device is deenergized to stop the loom, a branch electric circuit means including said device opening regularly at a given time in the loom cycle prior to arrival of the lay at said given point in the forward movement thereof, and a second branch electric circuit means including said switches in series, said second branch circuit being in parallel with the first branch circuit, and said second branch circuit effective to maintain said electromagnetic device energized upon opening of the iirst branch circuit means if both of said switches have been closed by the shuttle not later than said given time in the loom cycle.

11. In electric protection means for a. loom having a lay and shuttle to move across the lay, an electromagnetic device, loom stopping means controlled by the device effective to permit continued loom operation if the device is energized and effective to stop loom operation if the device is deenergized, two branch electric circuits in parallel with each other, each branch when closed causing energization of the device, means opening one of said branches at a given time in the loom cycle, and two electric switches on the lay normally open but closed successively by the shuttle and arranged in series in the other branch circuit and effective if both switches are closed by the shuttle not later than said time in the loom cycle to continue energization of said device during the time the rst branch circuit is open.

12. In electric protection means for a loom having a lay and a shuttle and dependent upon closure of an electric switch to permit continued loom operation, a plunger on the lay having a part thereof extending into the path of the Shuttle and the latter when passing the plunger exerting a force thereon moving the plunger out of said path, said switch being normally open and mounted on the lay and exerting a second force on the plunger tending to move the latter into said path of the shuttle, a sleeve supported by the lay surrounding said plunger, a spring operatively interposed between the sleeve and the plunger exerting a third force on the plunger opposed to the second'force, and means for adjusting the position of the sleeve relatively to the switch to vary the difference between said second and third forces and thereby permit adjustment of the force required to be exerted by the shuttle Vto cause the plunger to overcome the second force to effect closure of the switch.

13. In a lay for a loom operating with electric protection, a lay beam having a shuttle race, a plunger slidable vertically relatively to the beam and having the upper end thereof when in normal positionA extending above the race, a normally open electric switch supported by the lay operatively related to the lower end of the plunger and exerting an upward force on the latter tending to hold the upper end thereof in normal position, a sleeve surrounding the plunger supported by the beam, a spring operatively interposed between said sleeve and said plunger exerting a second force on the plunger opposing the force exerted by the switch, and means mounting the sleeve for adjustment on the lay in the direction of the length of the plunger to vary the force exerted by said spring against said force exerted by the switch.

14. In a lay for a loom operating with electric protection, a lay beam having a shuttle race, tubular member on the lay beam extending downwardly from the race, a plunger slidable within the tubular member having the upper end thereof above the race and tubular member, and an electric switch supported by the beam below the tubular member and the plunger and in position to be operated by the plunger when the latter moves downwardly within and relatively to the tubular member.

WILLIAM A. BLANCHARD.

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

UNITED STATES PATENTS Number Name Date 905,131 Bacon Dec. 1, 1908 1,790,335 Weissenborn Jan. 27, 1931 2,179,338 Lindegren Nov. 7, 1939 2,475,505 Kronol et al July 5, 1949 2,499,887 Sullivan et a1. Mar. 7, 1950

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