US2540987A - Clamp raising and lowering means for sewing machines - Google Patents

Description

M. M CANN Feb. 6, 1951 CLAMP RAISING AND LOWERING MEANS FOR SEWING MACHINES 5 Sheets-Sheet 1 Filed March 2, 1948 37m: '6 M'clmel 1c Cann ammm M. M CANN 5 Sheets-Sheet 2 Feb. 6, 1951 CLAMP RAISING AND LOWERING MEANS FOR SEWING MACHINES Filed March 2, 1948 Feb. 6, 1951 M. MOCANN 2,540,987

CLAMP RAISING AND LOWERING MEANS FOR SEWING MACHINES Filed March 2, 1948 5 Sheets-Sheet 3 M. M CANN Feb. 6, 1951 CLAMP RAISING AND LOWERING MEANS FOR SEWING MACHINES 5 Sheets-Sheet 4 Filed March 2, 1948 m PM M M M. M CANN Feb. 6, 1951 CLAMP RAISING AND LOWERING MEANS FOR SEWING MACHINES 5 Sheets-Sheet 5 Filed March 2, 1948 Patented Feb. 6, 1951 CLAMP RAISING AND LOWERING MEANS FOR SEWING MACHINES Michael McCann, Union, N. J., assignor to The Singer Manufacturing Company,

Elizabeth,

N. J., a corporation of New Jersey Application March 2, 1948, Serial No.12,*5'04 17 Claims. (01. 112--110) This invention relates to cyclically operated sewing machines such, for example, as button sewing machines, and more particularly to improvements therein which will facilitate the operation of the machine by relieving the operator of the necessity of manually raising and lowering the Work-clamp of the machine for :each sewing cycle.

A primary objectwof this invention is to provide, in an article attach ng machine such as cithatshown-in my United Statespatent applica- Ztion Serial No. 715,685, .filed December 12, 1946, now:Patent'No. 2,495,069. dated January 17, 1950, 2i. le. one .having a reciprocating and laterally vibrating needle-bar, means for automatically lowering the article-holdin work-clamp, and the article carried thereby, upon the work at thebeginning of'the sewing cycle and for'auto- .matically raising the clamp, to break the thread and-release the work, at the completion of the ;cycle.

.Another object is to provide an improved auto- 'matic clamp actuating mechanism adapted to .lower the work-clamp by the initial portion of the firstldownstroke of the needle-bar in a sewi-ing cycle and to raise the-work-clamp by the final portion of the last upstrokethereof, regardlessof the fact that those two strokes of the needle-bar are effected in laterally spaced ver- -.tical planes.

In my prior United StatesPatent No. 2,300,585, "November 3, 1942 there is shown, described and claimed an automatic clamp lowering'and raising mechanism actuated by the reciprocatory ..movements of a non-vibratory needle-bar. One of the objects of this inventionis to improve that mechanism so as-to adapt it to a sewing machine provided with a needle-bar which has .both reciprocatorv and vibratory motions.

1 An automatic clamp actuating mechanism of this natureis ideal when-the machine is fitted ;.with-a-clamp adapted to hold fiat buttons, as the flat button may be properly inserted into the clamp while the clamp ,is lifted. When the .clam-piis lowered-upon the work, the button will -..be held in :the properposition for the needle lto enter the holes inthebutton. However, under -.certain-conrlitions automaticraising and lower- -;ing of the clamp is not desirable. For example, whemthe machinetis fitted with a shank-button clampsuch as shown in the McCann United istatescPatent No. 2,131,012, September 20, 1938, the; button :cannct be properly inserted in the -.button-.clamp while the clamp is :in the raised .--.position because, in that 13051171011, the button- 5 holding arm of the .clampiis retracted anddoes not engage the back 'of the button to hold the shank thereof "in the button-supportin foot "fiorming a part :of the button-clamp.

ipresent Einvlention, therefore, has as an- 2 other object to :provide conveniently actuated means for rendering-theautomati'c clamp lowering and raising mechanism ineffective, or :inoperative, and forsmaintaining it-in an inoperative condition untilautomatic actuation. of the clampis again desired.

With the abovetand other objects in-view, as will hereinafter appear, the inventioncomprises the devices, combinations and arrangements of parts hereinafter :set forth and illustrated in the accompanying-drawings of a preferred embodiment of theiinventiom from which the several features of the invention and the advantages attained thereby will be readily understood by those skilled inthe art.

.In-the drawings, Fig. .lis a rear side elevation of a buttonsewing machine embodying the present invention, with a side cover plate thereof removed and with the bracket-arm head in sec- "tion.

Fig.2 is anenlarged'front end view of themachine shown in Fig. '1 with the major portion of the faceplate of-the bracket-arm head broken away.

Fig. 3 is an enlarged rear view, partly in section, of the bracket-arm head and a portion. of the bracket-arm, the automatic clamp lifting mechanisml-being shown in full lines as shifted to an inoperative position.

Fig. 4 is ahorizontal sectional view taken substantially on the line l- 1 of Fig. 3 with the bracket-arm shown :in elevation.

Fig. '5 is an enlarged end view of=the bracketarm head with the faceplateremoved.

Fig. 6-is'afragmentaryvertical sectional view of the bracket-arm head and parts associated therewith, the parts being in positions difierent from those shown in-Figs3.

Fig. 7 is a detailhorizontal sectional view taken substantially on the line .11 of Fig. 3.

Fig. 8 is a'detail' horizontal sectional view taken substantially on the line 8-8 of Fig. 2.

Fig.9.is a detail perspective view of the means for maintaining .the automatic clamp-lifting means in an inoperative condition when automatic 1 liftin v ofthe work-clamp is not desired.

Referring .more specifically to the drawings, the invention is disclosedsas .embodiedin an ar- .ticle attaching :machine, :having "a frame comprising a bed I, having a laterally extending work-supporting .arm .1 :a bracket-arm 2, consisting of a standardfl secured to the bed II, and

an overhanging arm 4 .;terminating in open-face bracket-arm head5 normally closed by aremovable faceplate-15a. The arm l is of substantially inverted :.U--1shape in cross section and is normally closed :by a removable sheet metal cover l having,,tat its :outer end. .a spring-- pressed hinged :cover 1. .Journa1edllengthwise of the arm 4 is a main or drive shaft 5 carrying 'needle-bar-driving shaft.

3 at its rear end, a pinion I driven from a gear 8 journaled on a stub shaft 9 secured in astopmotion bracket Ill fixed to the standard 3. Fixed to the gear 8 is a driving pulley I I, adapted to be driven from any suitable source, by a belt not shown. Also secured to the'gear 8 is a'notched stop-motion cam I2 which cooperates with aspring-pressed plunger I3 to bring the machine to rest after a predetermined number of stitches have been made. A loose pulley I4 also is journaled on the shaft 9 beside the drive pulley II and has the driving belt shifted thereto when the machine is brought to rest by the stop-,mov tion mechanism. The pitch diameter of the gear 8 is twice that of the pinion I and therefore that gear rotates'at only one-half the speed of rotation of the pinion I and shaft 6 which latter have one rotation for each stitch forming cycle. Thus it will be apparent that due to the slower speed of rotation of the gear 8 and stop motion cam the machine may be brought to rest with materially less strain and shock than can machines in which the driving pulley and the stopmotion cam are carried directly by the main or The stop-motion is provided with a treadle-actuated starting lever I (Fig. 2) and is held in running position by a spring-pressed latch I6 until the latch is autoet-arm head and has formed integrally therewith a vertically disposed sleeve 23 in which is reciprocably mounted a need e-bar 24 carrying,

at its lower end, an eye-pointed thread-carrying needle 25. Slidingly mounted in the head 5, parallelto but at one side and slightly rearward of the needle-bar, is a guide-bar 26 on which is slidingly mounted a tubular-portion 21 of a member'2I. This member'has a forked portion 2? adapted toreceivea slide-block 28 forming a part of a collar 29 clamped upon the upper portion of the needle-bar by a clamp screw 35. The collar 29 also carries an arm 3I which projects throughaslot 5 in the face plate 5 and has therein a'thread-eye 32. This arm 3| and eye 32 form a part of a thread take-up mechanism I which is shown and. described more fully in'my above mentioned application.

Vertical reciprocations are given to the member" 21, on the bar 25, by endwise movements of a link 33 journaled'at its upper end. upon'a pin 34' carried by the member 21 and embracing, at its other end, a crank-pin 35 carried by a crankdisk 36'secured upon the forward end of the rotary main shaft '6. The reciprocations of the member 21 are transmitted to the needle-bar and the needle carried thereby by the forked portion 21 slide block 28 and collar 29.

Cooperating with the needle, in the formation of stitches is a loop-taker 31, preferably in the .form of a wing-type rotary chain stitch loo-per Secured to and rotated by a loop-taker shaft 38.

that disclosed in my above mentioned application. L

Oscillation of the frame 2I for laterally shifting or vibrating the needle-bar transversely of the work-supporting arm I to cause the needle successively to enter spaced holes in a button is eifected from a cam groove 39 formed in one face of the cam wheel I8 hereinbefore mentioned. The specific means for transmitting motion from the camgroove 39; to the frame 2I forms no part of this invention and is designated generally as Reference may be had to my above mentioned application for a more complete description thereof.

Mounted upon the upper surface of the worksupporting arm I is a work-holder comprising a work-plate 40 and an overlying button-clamp 4!. The button clamp illustrated is adapted to hold flat buttons but it is to be understood that other forms of clamps may be substituted therefor, such for example as the shank-button clamp disclosed in my above mentioned Patent No. 2,131,012, September 20, 1938. The button clamp may be shifted lengthwiseof the worksupporting arm by the mechanism disclosed in my above mentioned application or by any'other suitable means.

Secured to the upper side of the button-clamp is a fork 42 which embraces a stud 43 carried by an arm 44 projecting laterally from a collar 65. This collar is secured upon the lower end of a spring-depressed clamp-lifting and clamp-depressing bar 35 mounted for vertical movement in the bracket-arm head 5. A coil spring 41 interposed between a Wall of the bracket-arm head and a collar 48, secured upon the bar 45, normally maintainsthe bar and the button-clamp depressed. The collar 48 carries a depending arm CFI ing the button-clamp during the final upstroke of the needle-bar in each article attaching cycle.

ts having an off-set stud-like portion 50. The bar 45 and the button-clamp connected therewith may be lifted, in opposition to the spring 41, by a treadle-actuated lever 5I, fulcrumed on a shoulder screw 52 threaded into a bracket 53 secured to the under side of the overhanging bracket-arm. The lever 5I has a forked end 5I which engages the stud 55. V

The collar 45 carries a forwardly projecting arm 54 formed integrally with a split collar 55, clamped upon the lower end of the guide-bar 26 hereinbefore mentioned. Thus the downward pressure exerted by the spring 41 is transmitted to the guide-bar 26 to urge it downwardly. Inasmuch as the guide-bar is rigidly connected with .the button-clamp the two move in synchronis'm.

Therefore when the button clamp is lowered by the spring 4'! theslide-bar 26 is similarly moved downwardly. Likewise 'when the slide-bar is moved upwardly, by means hereinafter to be described, the button clamp is raised in opposition to the spring 47.

Means, now to be described, is provided for shifting the slide-bar 26 upwardly, thereby rais- Clamped upon the slide-bar 25, within the bracket-arm head 5, is a collar 56 carrying a shoulder screw 51, upon which'is journaled the 5. latch member 58 is formed with a vertically disposedslot 58 through which passes the reduced forward end portion 59 of a lengthwise movable push-pull rod 59 which extends lengthwise of the arm 4, passing through an apertureefi in the rear wall: 5 .of the bracket-arm head. Nuts 60', 6| threaded on. the reduced portion 59 engage oppositefaces of the latch member 58 and cause thatrmemberto be swung about its pivot 51 by the end-wise movements of the rod 59; Acoil spring 82 surrounding the rod 59 and interposed between the' wall 55 of the bracket-arm head and the nut 60, normally tends to shift the rod and th'e latch lever toward the right as seen in Figs. 1 and- 4', to theposition illustrated in those figures.

.At its rear end the rod 59 is pivotally connect- .ed, by a coupling 63, to the upper :arm 64 of a two-armed lever 64- fulcrumed on a stud 84 threaded into the bracket-arm. The action of the coil spring 62 normally urges lever 64 to turn. in.:a clockwise direction, Figs. 1 and 3, thereby causing the free end of the lower arm 84 of the lever 54 to bear against the periphery of the rotating cam wheel l8, hereinbefore mentioned. Secured to the periphery of the cam wheel I8, 180 degrees apart, are cam blocks 65 adapted to ride under the free end of the lower arm 64* of the. lever 64 after t e stop-motion has been tripped to initiate the stopping of the mac ine near t e completion of a sewing cycle. The-cam block 65 turns the lever 64, counterclockwise. thereby shifting the rod 59 and latch member 58 from the position shown in Fig. 1 to the position shown in Fig. 6. thereby swinging the offset portion 58 of the latch member 58 into t e path of reciprocation of the shoulder 21 of the member 21 as that member andthe needlebar start their final upward movements, at the end of a sewing cycle. Thereafter the final upward movement of the member 21 lifts the latch member 58 and thereby the button-clamp as hcreinbefore described.

At the beginning of the next sewing cycle, the firstdownward movement of the member 21 and needle-bar 24 permits the latch member 58, uidebar 26, arm 54, and the bar 46 to descend under the influence-of the spring 41 thereby lowering the button-clamp upon a work-piece on the workplate 45!, as the cam block 65 moves beyond the lever arm .64.

From the foregoing it will be understood that the mechanism hereinbefore described will cause the work-clamp automatically to be lowered upon the work during the first downstrokeof the needle-bar at the beginning of each sewing. cycle and to be automatically lifted during the last upstroke of the needle-bar at the completion of each cycle. Due to thefact that .the. raising and lowering of the work-clamp is effected .by the member 2'! and not directly by the. needle-barthe lateral vibratory movements of the needle-bardo not in any way interfere with the proper "functioningof the automatic clamp lifting and lowering mechanism.

"Under certain conditions, such, {for example, as when using the machineto sew shank but- .tonsit may bedesirable to render the automatic clamp lifting and Ioweringmechanism ineffective.

This may be readily accomplished as now will "ton projects through an aperture 61 in the face plate .5. This. aperture isugenerally circular but has an ofiset. square portion 6.8; .(Tliig. 9 through which. is adapted to slide a ston-blockyia secured to the side of thepush-button. An; annular: flange ll formed on the push-button is, adapted. to em gage the. inner surface of. the. face.-p1at e to prevent withdrawal of: the push-button through-the aperture 61.

During the operation. .of the machine, when using; the. automatic clamp liiting-mechanismpthe push-button 5:6 is in its outermost position i;. e. with its flange 10: in contact: with the innerasurface of the; faceplate and. with the StOIDrblOQk 6'9 projecting through the square portion 68" of the aperture 5?, all as illustrated in: Figs. '1; i and Band in dotted lines in Fig. 3. Inposition the push-button has noeffect on the automatic clamp lifting mechanism and that mechanism operates as hereinbefore described.

When it is desired to render the automatic clamp lifting mechanism inoperative, the push-- button ii-E is pushed inwardly, in opposition'to: the spring. 62, from the position shown in Figs, 1, 4 and 8, and given a partial rotation to place:

' the outer end of the block 69 behind the inner surface of the face plate 5*, as shown in Figs. 3 and 9. This inward movement of the. push-b.ut--

ton shifts the rod 59, latch member 58. and lever 6 i to the positions shown in. full lines in Fig. 3

i. c. with offset portion 58 of the latch member 58. out of the path of movement of the shoulder portion 27 01 the member 21 and the free end. of the armfi l of the lever 54 out. of the. path .of' rotation of the cam blocks 65 on the cam wheel 158. With the parts in the positions shown in Fig. 8 the machine may complete its sewing cycle and be brought to rest by the stop motion mechanism without effecting lifting or'lowering' of the button clamp.

To again render the automatic clamp "lifting means effectiveit is merely necessary to rotate the push-button suiiiciently to align the block tfi', carried thereby, with the offset square portion 68 of the aperture 6! whereupon the expansion of the spring 62 will move the rod 59 endwise and shift the parts into their operative positions.

Having thus setforth the nature of the invention, what I claim herein is:

I. A sewing machine having, in combination, a re'ciprocatory and laterally vibratory needlebar adapted to have reciprocations in laterally spaced paths; a work-clamp; a member having a'horizontal sliding connection with the needlebar and mounted for vertical reciprocation in a fixed path at each reciprocation of said needlebar; a stop-motion device constructed and arranged to bring the machine to rest at completion of a predetermined sewing cycle; and a normally ineffective coupling element and means for actuating said element in timed relation with said stop-motion device to cause it to couple said member to said work-clamp for autoinatic lifting of the latter asthe machine comes to rest.

g 2. A sewing machine having, in combinatioma reciprocatory and laterally vibratory needle-gbar adapted to have reciprocations'in laterally spaced paths a spring-depressed Work-clamp; a'memher havinga horizontal sliding connection with the needle-bar and mounted for vertical reciprocation in a fixed path at each reciprocation of said needle-bar; a stop-motion deviceconstructed and arranged to bring the machine 'to rest at the completion-of a predetermined sewin cycle; means including a rotary element for controlling the action of said stop-motion device; and coupling means actuated by said rotary element and operating in timed relation with said stop-motion device to couple said member to said work-clamp for automatic lifting of the latter during the final upward movement of the needlebar.

3. In a sewing machine having a head, a vertically reciprocatory and laterally vibratory needlebar mounted in said head, means for reciprocating and vibrating said needle-bar, a workclamp, and astop-motion device constructed and arranged to bring the machine to-rest at the completion of a predetermined sewing cycle; the improvement which consists in the provision of a slide-bar mounted in said head and connected with said work-clamp; a member slidingly mounted on said slide-bar and reciprocating with said needle-bar; and means operated in timed relation with said stop-motion device to connect said member to said slide-bar for automatically lifting said slide-bar and work-clamp at the completion of the sewing cycle.

4. In a sewing machine having a head, a vertically reciprocatory and laterally vibratory needlebar mounted in said head, means for reciprocating and vibrating said needle-bar, a work-clamp, and a stop-motion device constructed and arranged to bring the machine to rest at the completion of a predetermined sewing cycle; the improvement which consists in the provision of a slide-bar mounted in said head and connected with said work-clamp; a member slidingly mounted on said slide-bar and reciprocating with said needle-bar; a, latch member pivotally secured to said slide-bar and normally maintained out of the path of reciprocation of said memher; and means operated in timed relation with said stop-motion device to shift said latch-memher into the path of reciprocation of said member to cause said member to lift said slide-bar and work-clamp at the completion of the sewing cycle.

5. In a sewing machine having a head, a vertically reciprocatory and laterally vibratory needl -bar mounted in said head, means for reciprocat ng and vibrating said needle-bar, a work-clamp, and a stop-motion device constructed and arranged to bring the machine to rest at the completion of a predetermined sewing cycle; the imn-rovement which consists in the provi ion of a slide-bar mounted in said head and connected with said work-clamp; a member slid ngly mounted on said slide-bar and reciproeating with said needle-bar: a shoulder provided by said member: a latch member pivotally secured to said slide-bar and having an ofiset portion; and means operated in timed relation with said stop-motion device to swing said latch member into a position in which said oifset portion overlies said shoulder to cause said member to lift said slide-bar and work-clamp at the completion of the sewing cycle.

6. A cyclically operated article-attaching machine combining a head; a pivotally mounted article-holding clamp; stitch-forming mechanism including a reciprocating needle-bar mounted in said head; a clamp-lifting bar-slidingly mounted in said head and connected with said clamp; a clamp-lifting member slidingly mounted on said bar; means connecting said member with said needle-bar for reciprocation therewith; a latch memberpivotal-11y secured said bar; spring means acting on said latch member for holding it out of the path of reciprocation of said clamplifting member; and means acting in opposition to said spring means for shifting said latch memher into the path of movement of the clamplifting member during the final upward movement of the needle-bar in each sewing cycle.

'7. In a sewing machine having a head, a vertically reciprocable and laterally shiftable needlebar mounted in said head, means for reciprocating said needle-bar, means for shifting said needle-bar laterally between successive reciprocations thereof, a work-clamp, and a stop-motion device constructed and arranged to bring the machine to rest at the completion of a predetermined sewing cycle; the improvement which consists in the provision of a clamp lifter located in said head and connected with said workclamp; a member slidingly mounted on said clamp lifter and having a sliding driving connection with said needle-bar in all lateral positions of the needle-bar; and means operated in timed relation with said stop-motion device to connect said member to said clamp lifter for actuating said clamp lifter to cause it to lift said workclamp by the final upward movement of the needle-bar at the completion of a sewing cycle.

8. A sewing machine combining a reciprocatory needle-bar; a work-clamp; a stop-motion device constructed and arranged to bring the machine to rest at the completion of a predetermined sewing cycle; automatic means including a shiftable member operated in timed relation with the stop-motion device to couple said needle-bar to said work-clamp for automatically lifting the latteras the machine comes to rest; and a manually operated element for holding said shiftable member out of operative position to render said automatic means ineffective.

9. A sewing machine combining a reciprocatory needle-bar; a work-clamp; a stop-motion device constructed and arranged to bring the machine to rest at the completion of a predetermined sewing cycle; automatic means including a spring-biased latch member operated in timed relation with the stop-motion device normally to couple said needle-bar to said work-clamp'for automatic lifting of the "latter by the last upstroke of the needle-bar in a sewing cycle; and a manually operated element for shifting said latch member to an inoperative position to render the latch member ineffective to couple said. needlebar to said work-clamp.

10. A sewing machine combining a reciprocatory and laterally Vibratory needle-bar adapted to have reciprocations in laterally spaced paths; 2. work-clamp; a member mounted for'vertical reciprocation in a predetermined'path at each reciprocation of said needle-bar; a stop-motion device constructed and arranged to bring the machine to rest at the completion of a predetermined sewing cycle; counling means operated automatically in timed relation with said stepmotion device to couple said member to said work-clamp for eiiecting automatic lifting of the latter as the machine comes to rest; and manually, actuated means for shifting said coupling means out of the path of movement of said member Jrendering said automatic clamp-lifting means ineffective. v

11. A cyclically operated sewing machine cornbing a head; a pivotallyfmounted article-holding clamp; stitch-forming mechanism including a reciprocating needle bar mounted said headi a clamp-lifting bar slidingly mounted in said head and connected with said clamp; a clamp-lifting member slidingly mounted on said bar; means connecting said member with said needle-bar for reciprocation therewith; a latch member secured to said clamp-lifting bar and having a portion movable into the path of movement of said clamp-lifting member; spring means normally maintaining said latch member out of the path of movement of said clamp-lifting member; automatic means operating in opposition to said spring means for shifting said latch member into the path of movement of the clamp-lifting member during the final upward movement of the needle-bar in a sewing cycle; and manually actuated means for rendering said automatic means ineffective to lift the clamp.

12. A cyclically operated article-attaching machine combining a frame includin a bracketarm and a bracket-arm head; a pivotally mounted article-holding clamp; stitch-forming mechanism. including a reciprocating needle-bar mounted in said head; a clamp-lifting bar slidingly mounted in said head and connected with said clamp; a clamp-lifting member slidingly mounted on said bar; means connecting said member with said needle-bar for reciprocation therewith; a latch member secured to said clamp-lifting bar; a rotary cycle-control member journaled on said frame; means actuated by said cycle control member and extending lengthwise of said bracket-arm for shifting said latch member into the path of movement of the clamp-lifting member during the final upward movement of the needle-bar in a predetermined sewing cycle, to effect automatic lifting of the buttonclamp; and manually operable means for shifting said latch member out of the path of movement of said clamp-lifting member thereby to render said automatic clamp-lifting means ineffective.

13. A cyclically operated article-attaching machine, combining a frame including a bracketarm and a hollow bracket-arm head; a face-plate secured to said head; a pivotally mounted articleholding clamp; stitch-forming mechanism including a reciprocating needle-bar mounted in said head; a clamp-lifting bar slidingly mounted in said head and'connected with said clamp; a clamp-lifting member slidingly mounted on said bar; means connecting said member with said needle-bar for reciprocation therewith; a latch member secured to said clamp-lifting bar; a cam-actuated rod extending lengthwise of said bracket-arm for shifting said latch member into the path of movement of the clamp-lifting member during the final upward movement of the needle-bar in a predetermined sewing cycle to effect automatic lifting of the work-clamp; and a manually operable member carried by said face-plate for shifting said latch member out of the path of movement of said clamp-lifting member to render the automatic clamp-lifting means ineifective.

14. A cyclically operated sewing machine combining a head; a face-plate secured to said head; a pivotally mounted work-clamp; stitch-forming mechanism. including a reciprocating needle-bar mounted in said head; a clamp-lifting bar slidingly mounted in said head and connected with said clamp; a latch member secured to said clamp-lifting bar and normally disconnected from said needle-bar; automatically actuated means for shifting said latch member to cause it to connect said needle-bar with said clamplifting bar during the final upward movement of the needle-bar in a sewing cycle; and manually operable means carried by said face-plate to shift said latch member to an ineffective position thereby to render said automatically actuated means inoperative.

15. In a sewing machine having a head, a vertically reciprocatory needle-bar mounted in said head, means for reciprocating said needle-bar, a work-clamp, and a stop-motion device constructed and arranged to bring the machine to rest at the completion of a predetermined sewing cycle; the improvement which consists in the provision of a slide-bar mounted in said head and connected with said work-clamp; a member slidingly mounted on said slide-bar and reciprocating with said needle-bar; a latch lever pivotally mounted on said slide-bar and normally biased to one of two extreme positions in which it is out of the path of reciprocation of said member; means operated in timed relation with said stopmotion device to shift said latch lever into an intermediate position and in the path of reciprocation of said member to connect said member to said slide-bar for automatically lifting said slide-bar and work-clamp by the last upstroke of the needle-bar at the completion of the sewing cycle; and manually actuated means for shifting said latch lever to its other extreme position and for locking it in the last named position to render the automatic clamp-lifting means ineffective.

16. In an article-attaching machine having stitch-forming mechanism including a reciprocating needle-bar, an article-holding clamp, and means including a latch member actuated by the needle-bar during one only of a predetermined plurality of upward movements thereof for automatically lifting the article-holding clamp; the improvement which comprises the provision of a manually operated element engaging said latch member for shifting it to an inoperative position to render said clamp-lifting means ineffective.

1'7. In a cyclically operated article-attaching machine, in combination, a head; stitch-forming mechanism including a reciprocating needle-bar mounted in said head; a member reciprocated with said needle-bar; an article-holding clamp; automatic clamp-lifting means including a latch element connected with said clamp and adapted to be swung into the path of movement of said member during the final upstroke of the needlebar for normally causing the needle-bar to lift the clamp; and a push button mounted in said head and constructed and arranged to act on said latch element to hold it out of the path of movement of said member to render the automatic clamp-lifting means ineffective.

MICHAEL MCCANN.

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

UNITED STATES PATENTS Number Name Date 2,158,199 Reece May 16, 1939 2,300,585 McCann Nov. 3, 1942

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