US2357749A - Presser device for tacking machines - Google Patents

Description

Sept. 5, 1944.

M. MccANN PRESSER DEVlcE FOR TACKING MACHINES Filed July 23. 1943 Patented Sept. 5, 1944i l l UNITED "STATES PiiTlZNv'lv ff-OFFICE massen navlcaron' 'rAeKINGMAcmNs 'Michael'McCanm ElizabethLN. It, assigner The Singer Manufacturing Company, Elizabeth, l N. J., acorporationofNew-Jersey Application' July 23, '1943, seriaino. 495,365

- .7 claims. (ci.

machine comprising abase' LI .standard 2, ,over- This invention relates to 'presser-devices for tacking machines and it has as an objeet'toi'my prove` they presser-devicedisclosed vin United Statespatent to Becker, No..i,3 50,290, 'A ugust.2 4,

Stated more specifically, this'inventio-n has as hanging bracket-arm l `and lbracket-arm head an object to provide an'improved and vsii'npliiied v presser-device particularly adapted forrhold'ing the bows of hats while they-are being attached to the hats by a conventional ltacking machine.

These and other objects have been` attained by unit, into and out of operative position.,

In the present improved device the work-pressing elements' are adapted to have a slight free swinging movement abouttheir fixed pivots to ypermit them to move back and forth with the 4, the latter carrying the usual reciprocating needie-bari'and'spring-depressed presser bar 6. At

its lower end the needle-barl carries Aan eyepointed needle-'1 (Fig. 2) which cooperates with aconventlonal rotary chain stitch looper 8 in the vshown,ladapted-to engageloose `and fast pulleys 9 and I0, respectively, on therear end of a-main vshaft I-I Journaled lengthwise .of the arm 3. The

i forward end offthe main shaft'is connected,

w'through` conventional means, .not ,showin to re- V i'The rotary .chair'i-stitchlooper 8 is carried by the forward-end of arotary :louper-shaft I2 ciprocate the needle-bar `5.

' journaledllengthwise inV a work-supporting arm work while the work is shifted relative t the stitch-forming mechanism to produce the'tack. Also in the present construction the presserdevices are normally spring biased to a vretracted position to facilitate insertion and proper positioning of the needle in its socket in the needlevbar, and a manually releasable'latch' member'is provided to maintain thepresser-devices'in their effective o r operative position d uringthe tacking 1 operation;

l A drawing illustrating-a v"preferred embodiment f a of this invention has been annexed asa part."

of this disclosurel and in such'drawing'f.

Fig. 1 is a side elevation of a tracking-machine 'Fig 2 ist an enlarged front view-of the presserdevice.- showing it attached to a conventional I3 f'lrininga` part of the bed l. The loopershaft is rotated from the main shaft I I at a 1-to-1 ratio through the medium ol! alirst pair lof bevelv gears I4, I5, a vertical shaft, I6, journaled'inthe standard 2 and a'second pair of bevel ygears I1, I8.

' YJournaled vho rizontally in the standard 2 is a cross-shaft I9 to vwhich is secured av clamp-ae-V tuating and v,c :ycle-cont'rol cam-wheel 20.. shaItisdrivenfrom the main shaft II, at a reduced speedyby'l a; worm 2i and wormwheel 22 as is common in this type 'of sewing' machine.

Slidingl'y mountedon theuppersurfaceiof the work-supporting arm I3 is anlendv'risereciprocable work-plate having, atl -its' forwarden d, ay serrated vwork-supporting portion adapted to underlie and 'reciprocate'the work relative to the spring-depressed presser-bar and illustrating its f 'j normal position relative to .theneedle and needlebar.

Fig. 3 is a side view ofthe presser-device shown, in Fig. 2, illustratingg-iri dot-dashlines, the swinging movement of the presser-'members' un der the'inuence of the work-shifting means and, in dotted lines, the presser-members swung to their retractedposition. l'

1i ig.-4l is a disassembled '.perSpectiveview of parts of the improved presser-device, showing the main supporting bracket thereof 'attached to a presser-bar.

Referring more specifically tothe drawing, the vinvention is disclosed as embodied vin a'tacking adjustably mountedon a-stud 32isecur'edto and Thus-'rotation of the cam-wheell causs the.

stitch-forming mechanism. A work-guide or 4gaug'e'25v is carried'by the work-plate and serves.

to locate the work relative tothe stitchingpoint. Endwise reciprocations are given tothe workplate 2 3 from. 'a cam-groove 26 formed rorithe'in- 'ner face of cam wheel 20, through the medium i of ai two-armedjlever 21 journaled, vat 28, on a bracket 2 9secured tothe base I. The upper arm 2* o'f the lever 21 carries a roller 30 'which' tracks the camgroovejrwhile the lower armi 2'Ib thereoils channeled and vembraces 'a swivel-block .3|

projecting upwardly from the work-plate 23.

work-plateV andthe work. carried therebyt o be arm' Il 'during operation f .the stitch-forming reciprocated back an'd forth (lengthwise -of the mechanism ardlin timed relationtherewith to cause thel stitch-forming' mechanismtoform a group of'tacking stitches. Ihe lengthof the'tack' 4is determinedxbythe setting-of the swivelblock 3l -inthe channel-or the lever-arm 21". After.'

a predetermined number of tacking stitches have been made the machine is automatically brought to rest by a stop-motion mechanism, designated generally as 8, whichyin tu'rn is controlled'by the cycle-control cam-wheel 20.

Cooperating with the serrated portion 24 of the work-plate in holding the work, is the improved scans i bar 3. may be raised, in opposition to its .depressing spring-(not shown) to permit placing 'oi' 'the' work on, the work-plate and beneath the presser device, by manual actuation of a lever lll Iulcrumed at 5l on a bracket '52 secured upon Athe arm 3. One end of the lever 30 is lforked and engages beneath a collar |53 secured upon the presser-bar. The opposite endof the lever may presser-device which comprises a main supportlng bracket 33, securedto the lower end oi press# er-bar 6 by screw 34. This bracket has depending and laterally spaced, ears 33. and 1 3 4, connected together by a cross-bar 33, betweenwhich l the medium of a is pivotally mounted, on screws `3`|y and 33,' ag work-pressing member 39. This -member com' prises spaced work-engaging elements 40 4I connected together at their lupper ends byal bridge portion 42. The elements 40, 4I have,

at their lower ends, spaced and outwardly ared foot-portions 40* and 4l,resp.ectively, between which the needle reciprocates; The pivot screwsv 31, 38 pass freely through apertures 3l* and 3l` in the ears 35 and 36, respectively, aridV 4are threaded into apertures 39* lin the member 33.

A coil spring 43 surrounds the shank of the screw 33 and has two outwardly projecting legs 43, 43h oi' which one engages behind the element 4I while the other engages behind the cross-bar be'conne'cted to.v any suitable treadle or lever vertically shiitable presser-bar, and a workspresspressing device comprising a bracket secured toy ing device carried by said presser-bar, said worksaid presser-bena plurality of vertically disposed v work-engaging elements pivotally mountedvon said' bracket, spring means urging said elements engaging elements being adapted tol be A'shiftedin one. direction about their pivots, and a stop for limiting they movement of said'elements under the influence ofv said spring means, said workin the opposite direction. in opposition to said 33.* of the bracket 33, between theears 3l 'and- 36. The tension of spring-43n normally tends `to turn the member 39 yclockwise (as seen in Figa-1A and s) aboutitspi'vots s1, lsato meposition'indicated in dotted lines in Fig. 3,' in which position upwardly extending lugs ,40 and 4Ib'on th elef ments 4.0,-4I, respectively bear against the "inner face of thecross-bar 33'?, as shown in dotted-lines in Fig. 3. This tendency of the member 3 3 to including a verticallyreciprocable needle,

turn about its pivots'isr resisted by a manually releasable latch mechanism now-to be'described.

Slidingly mounted in an aperture 44 in the ear 36 is a spring-pressed plunger,- the ireeinner4 end oi' which is adapted to enter a somewhat larger opening 48 in the element 4 vI. v,The plunger is normally pressed' inwardly by a leaf-spring 41 secured, by hook. portion "rand screw 4l, upon the carin/and having, inits lower portiomja' keyhole shaped slot 471 in the smaller lower end of which is fitted a reduced neck portion of the plunger 4I. 'l'.'he louter end or theplunger is knurled,y as'atf49, to provide a-ilnger-grasp by means ofi which the' plunger may be drawn outwardly, in opposition to' the leal-spring 41,' to .v

spring means, by the movement of the work on saidwork-support. I

2, In a sewing-machine, stitch-forming mechaa horizontally reciprocable work-support, a

'-presser-bar, and a work-pressing device including a bracket carried by said presserbar` and a pair of work-engaging elements .pivotally moun-tedon said bracket at opposite' sides of said needle and shiftable by the workheld on said worksupport.

g 3. A Apressen-device for sewing machines'comprising a presser-bar, a supportingbracket carried thereby, a pair of work-,engaging elements pivoted on said bracketyspringmeans'for shifting s aid work-engaging elements from an` operative position to a retracted position, and latch means act-` .Said Spring means to main--v ing in opposition to tain said elements in operative position; K

4. A presser-device for sewing machines comprising a supporting bracket having a pair oi spaced vertically disposed ears, a work-pressing.

member pivoted between said ears and including a pair of work-engaging elements, spring means for swinging said'work-pressing member withdraw the free inner end fromthe aperture 46. When this is accomplished, the work-pressing member is swung upwardly about its pivot to the retracted position shown infdotted lines in Fig. 3,

as hereinbeforedescribed, ,In this retracted positionthe free end ofthe 'plunger 45 bears Lagainst the'sideoi' the work-engaging element 4| and remains ready tosnap into'v the. opening 43 when the presser-member is againjswung downwardly into operative position; The 'diameter ofthe opening 43 is somewhat greater than the diameter ot the end o1 the plunger which projects thereinto.- lThus-the member 33 is permitted to. have a limited swinging movementfabout its pivots as' the work-plate 23 andthe work thereon are reciprocated lengthwise of the arm I3 yand therefore, during the tacking operation, there is no relative movement between the work andthe footportions 4lln and 4|* of the presser-members 4I and". l

'As abovegstated, the presser-,device is carried l Aby the lower end of the spring-depressed Preel'- 75 y f8. A presser-device i'or a sewing machine havabout its pivot to position said elements in a retracted position, and a manually-'releasable latch means carried by said bracket and engaging saivzi member and. acting in opposition to said spring means normally to maintain said work-engaging elements in operative position.

g 5. A presser-device for sewing machines having Y a re`ciprocating work-support, comprising a supporting bracket, `a pair of work-,engaging elements pivoted onsaid bracket, one of said elements being'provided with an aperture, spring means tending to shift said work-engagingelements out of operative position, anda spring-pressed plunger carried by said bracket and having one end entering said aperture. to maintain saidl elements in operative position in opposition to said spring means. there being sumcient play between the walls of said aperture and the portion of the plunger therein to permit said elements to be shifted back-and forth with a work-piece on the reciprocating work-support.-

ing a. reciprocable work-holder, a presser-bar and stitch-forming mechanism including a reciprocating needle. comprising a bracket secured upon said presser-bar, a pair of work-engaging elements pivoted on said bracket. spring means for shifting said Work-engaging elements to a retracted position, latch means acting in opposition to said spring means to maintain said elements in operative position in contact with a work-piece on said work-holder, and a lost-motion connection between said work-engaging elements and said latch means to permit said members to oscillate as said work-holder and work-piece are reciprocated.

7. A presser-device for a sewing machine having a reciprocabie work-holder, a presser-bar, and stitch-forming mechanism including a reciprocat..

ing needle, comprising a bracket secured upon said presser-bar, a unitary work-pressing member pivoted on said bracket and including spaced but integrally connected work-engaging elements, one of which is provided with an aperture, spring means for shifting said work-pressing member to a. retracted position, manually reieasable latch means including a spring-pressed plunger having one end entering said aperture to maintain said elements in operative position in contact with a work-piece on said work-holder, the diameter of said aperture being materially larger than the diameter of the end of the plunger therein thereby permitting said work-engaging elements to oscillate as said work-holder and Work-piece are reciprocated. MICHAEL McCANN.

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