US1239239A - Sewing-machine work-handling mechanism. - Google Patents

Description

1. WHITELAW. I SEWING MACHINE WORK HANDLING MECHANISM.

APPLICATION FILED JUNE 26, 191 6.

I Patented Sept, 4, 1917.

3 SHEETS-SHEET i.

'J. WHITEL'AW.

sewme MACHINE WORK HANmmGmEcHAmsM.

' APPLICATiON FILED JUNEZG. ialfi.

Patented-$3M. 4,191?

3 HEETS-sHEET 2 mmw,

J. WHITELAW.

SEWING MACHINE WORK HANDLING MECHANISM.-

APPLICATION FILED JUNEZG, 1916.

11,239,239 Patented. Sept. 4,1917.

3 SHEETS-SHEET 3.

JAMES WI-IITELAW, OF ST. LOUIS, MISSOURI.

SEWING-MACHINE WORK-HANDLING MECHANISM.

Specification of Letters Patent.

Patented Sept, 4t, 1913.

Original application filed November 1913, Serial No. 802,732. Divided and this application filed June 26, 1916. Serial No. 105,799.

To all whom it may concern:

Be it known that I, JAMES WHITELAW, a citizen of the United States, residing at St. Louis, and State of Missouri, have invented certain new and useful Improvements in Sewing-Machine Work-Handling Mechanism, of which the following is a specification.

' My invention relates to sewing machine work handling mechanism and in some of its features more particularly to blind stitch sewing machines.

The general object of my invention is to. provide a simple and efficient feed and plunger mechanism, and operating means therefor, for cooperation with a stationary presser foot to present portions of the work to be stitched in a presser foot opening, holding the goods at the time of such presentations snug and taut around the bender and handling the work uniformly and with certainty under high speed conditions.

Another object of my invention is to provide a simple and effective construction enabling the moving parts of the work-handling mechanism all to be displaced from normal position, so as to permit insertion or removal of work, at any time in the cyclic operation of the parts.

In the drawings wherein I have illustrated an embodiment of my invention Figure 1 is a front elevation of a blind stitch sewing machine, with parts of the frame broken away to expose the work handling mechanism Fig. 2 is a section on line 22 of Fig. 1;

Fig. 3 is an enlarged end View of the work handling mechanism and associated presser foot parts;

Fig. 4 is a section on line l4 of Fig. 3;

Fig. 5 is a cross section on line 55 of Fig. 1;

Fig. 6 is a detail of the feed-length controlling cam;

Fig. 7 is a section of the plunger shaft on line 77 of Fig. 1; i

Fig. 8 is a section on line 8-8 of Fig. 4:; and

Fig. 9 is a section on line 99 of Fig. 3.

The blind stitch sewing machine shown in the drawing has a frame 10 comprising the upper and lower arms 11 and 12, n

intervening post or standard 13 and in general provides suitable stltch forming mechanism l4 hereln shown as of the chain stitch type involving a curved reciprocating needle 15 and a complemental looper mechanism 16, both arranged to work above a stationary presser foot 18 which has therein an appropriate aperture 19 through which the goods may be presented to the needle. l/Vith the character of the stitch forming mechanism, the presentinvention is not concerned, but'a stitch forming mechanism, of which fragments are illustrated in Fig. 1 is specifically shown and described in my copendingapplication, Serial No. 802,733, filed November 21th, 1913, which on July 11th, 1916, matured into Patent No. 1,190,- 833. The present application is a division of my copending a plication, Serial No. 802,? 32 entitled Sewing machine work handling mechanism filed November 2&th, 1913, which on September 19th, 1916, matured into Patent No. 1,198,800.

20 is a main shaft extending through the upper arm 11 of the machine and driven by the hand wheel pulley 21, said main shaft serving to actuate the stitch forming mechanism and having operating connections through mechanism contained within the post 13 with the work handling mechanism carried by the lower arm 12. The lower arm 12 is hollow from its juncture with the post 13 to an integral end block or head 22 preferably arranged slightly out of alinement with the presscr foot 18 so that mechanism supported outside of said block 22 may aline with the presser foot, a detachable cover 23 secured on the block 22 by screw 2% may inclose the space in which the work ing parts move.

The goods handling mechanism, generally indicated at 25, comprises in the specific construction shown a feed dog 26 to cooperate with the under side of the presser foot, a clamp member 27 coordinated with said feed member and also cooperating with the under side of the presser foot 18 and a ,plunger 28 cooperating with the aperture 19 of the presser foot 18 to present a bend in the goods therethrough to the operation of the needle, with actuating connections and regulating devices for these parts.

.A feed dog 26 shaped to provide separated side points 26 receives a 4-way mo tion to perform its effective feeding operation by moving toward the rear of the machine. Specifically dog 26 has a rearward, substantially horizontal extension 30 pivotally connected as at 31 with a substantially vertical crank 32 which is fast ona driving rock shaft 33, the rocking of which in a horizontal direction contributes theforward and backward motions to the feed. For elevation and depression, the feed member has a connection between its ends as at 34 to a substantially vertical link 35, said'link 85 pivotally connected as at 36 betweenthe ends of a lever 37, one extremity of which is pivotally connected as at 38 to a genera'lly-horizontal crank arm 39 carried by a rock shaft 40, sothat the rocking of the shaft elevates and depresses the crank arm "1'5 3'9 and with it the attached end of the lever '37. The remote end of said lever 37 is piv- "oted as at 41 to a link 42 suspended from a pivot 43 which, I prefer, shall receive support froma vertically movable carrier. 'Dis- 2 0"regarding possible movement of the suspension point 43 it will be obvious that "tro'cking of the shaft 40 serves to elevate or depress the feed dog 26 with lever 37 workon 41 as a fulcrum and by appropriate 2 5'timing of the rocking operations of shafts 33 and 40, the feed part may be madeto "effect its desired 4-way cycle of movement.

The clamp member 27, is preferably formed with a short head serrated transiu versely as "shown in Fig. 4 and disposed beftween two tooth points 26 of the feed dog "26, so as to work in a central slot of said feed dog. Said clamping head isintended, in'thc normal working operation, to clamp "35the goods against the under side of the p'resserfoot during the time when the feed "dog is out of engagement with the goods and'to be removed from holding position "when the feed dog is exerting its'feeding in- "40 ffl'uence. To this end the clamp member and "feed dog are inter-related for appropriate cooperation controlled by the operating mechanism for the feed dog. The clamping head '27 is carried by a vertical post 45,

" sliding against head 22 and having guiding wings4'6 atitssides working in grooves made therefor in the retaining plates 47, said'sliding po'st constituting'a' carrier afraining a bearing for the pivot 43 on which *thelink 42 is suspended.

i I"p'rovidein (3011]11I1Ctl011 with the mechanism described means normally to hold the post 45 in raised position but to effectiits V "depression'at will. Specifically I provide a 5 5 'rod '50 extending along the front of the [machine through a suitable bearing "51 near fthejun cture of the arm 12 and post 13'and through a bearing in the said block 22, and on the extremity of said arm I provide a o'finger 53 engaging in a recess 54provided 'therefor inthe outer face of thepost '45. 'Thisrod is appropriately provided at'its otherend with alever 56 to which the customary"kneelift may be attached'and'sai'd 7 "lever is actedon by a spring "57' normally tending to rotate the rod and through thefinger 5 3-to liftthe post 45.

The relation of the parts and the throw of the rock shaft:;40"are"such that the clownward sweep of crank 39 when the feed dog has completed its feeding movement, causes 161761337 to fulcrum on pivot 41 and through link 35 to retract the feed dog "from "the presser foot, but when the feed dog is raised, by the upward sweep of the crank 39, for commencement of the feeding action ofthe dog, said feed dog comes in contact with the underside of thepresser footbefore the throw of crank 39 is" completed and thenthe lever 37 fulcivuming onithe pivot 36 acts "as a lever} of the "first class to draw downward upon 'the' link 42therebywithdrawing the clamp 27 from engagement with the under side of the'presser foot or with thework, as best sh own in Fig; 3.

The link 'arrangement-shown permits the 7 post 45 to be lowered, depressingthesubstantially' vertical link 42 and thereby drawdown the link 3 5 and the feed dog 26to pointrwhere' the feed dog and clamp member'are both withdrawn from the presser fo'ot sufliciently for insertion of the work between the feed and clamp parts and "presser "foot. WVhen so withdrawn,'opera- .tion of the machine to actuate therock shaft causes thefeed dog to go through an idle or useless 4 way motion but it will beapparent 'that by this arrangement the with drawal of the feed "dog and clamp from the presser 'foot' to permit insertion of thework maybe efl'ected whilethe machine is running, if desired,at any part of its cycle of operation.

The plunger '28 is carried by and bodily moves with the post 45, but may move a lim- "ited distance with respect to said carrier or post 45. Specificallythe plunger 28 is a cylindrical "stem' bearing at its upper ex- .tremitya properlyshaped head 60, shaped "to form a ridgein the goods transverse'to the path of the needle,-andat its lower end 'hav'i-nganenlargementor base 61. Said stem fits' within an"appropriate bore 62, in *the post 45, and is normally depressed b'y-a spring 63 acting between an upper shoulder of "the bore' andthebase 61 toforce said plunger downintothe postto the full extent permitted by the play at pin 64' carried by-the stemwithin a -slot"'65,- cut in the upper portion of thevpost 45. T-he; lower end of-the plunger base 61 proj ects below the post 45 to such distance that in the normal operation of the device full elevation of base 61 of the plunger may project head 60, against the tension of spring 63, to a sufiicient height to present a node of goods through the presser-foot opening 19 tothe neec le.

For actuating the plunger to giveit its movementsrelative to the clamping post 45 I whichcarries itgI providethe rocking shaft 130 66 extending longitudinally of the frame, and bearing on its extremity a crank arm 67, the extremity of which, acting against the plunger base 61 to elevate the plunger, preferably carries a pin 68 extending longitudinally of the machine into a recess 69 provided therefor in the end-block 22, the range of throw of said crank arm 67 being regulable by an adjusting screw 7 0 extending from an exposed position upon the arm down through the end-block 22 into recess 69 to form an adjustable stop for pin 68. i

It will be understood that the several rock-shafts are 33, 40 and 66, operated in appropriate timed relation by mechanism at the rear end of the machine, driven by the main shaft, and as has heretofore been stated the cyclic operations of the two rockshafts 33 and 410 are not interfered with at all by the movement of the feed and clampmechanism from normal position to depressed position for goodsinsertion. The rock-shaft 66 tends in its normal operation invariably to raise the plunger stem to a predetermined position, but I prefer that this elevating action shall be permitted by the plunger only when the cloth holding and feed mechanism are in normal relation to the Work, the movability of the plunger with respect to the post 45 being limited by the extent of projection of base 61 of the plunger from the bottom of the post. In order, therefore, that parts may not be broken when extra heavy work is inserted or when the feed-dog and clamp-post are depressed by the operation of lever 56 while the machine is running, the driving connections with the plunger operating crank 67 of the driving gearing should include a yielding part and I prefer that the shaft 66, intermediate its ends, be flattened as at 66 (Fig. 7) so that said shaft may operate as a strong torsion-spring. Thus, although positive rocking movement is imparted to the rear end of shaft 66, when its crankarm 67 encounters the bottom of clamp post 415 while the latter is depressed below normal position the torsion-spring action of the shaft 66 yields under the opposing power and resistance and prevents breakage of the parts, the plunger not being raised far enough to prevent goods-insertion.

The three shafts 33, 40 and 66, are all preferably driven by eccentrics on the main shaft. The rocking motion of shaft 33, which imparts the fore-and-aft motion to the feed dog 26 should be variable in order that the feed between stitches may be varied, and to this end I provide means for adjustment of the throw of the eccentric, onthe main shaft, which operates the rock-shaft 33. Specifically indicates a disk on the main shaft 20 secured thereon "as by screws 81, said disk having in; its face a slide-way ing diametrically across the face of the disk, having a central opening 84: surrounded by a cam annulus 85 which, by adjustment of the plate transversely of the disk, may be thrown to different degrees of eccentricity to the shaft 20. The plate 83 is retained in its slide-way on the disk by engagement of the notch 86 in the edge of the plate under the head of the screw 87 carried by the disk, and for diametric adjustment of the plate I provide at one edge of the plate a. flange 83 overhanging and bearing upon a pair of springs 88 which are seated in a recess made to receive said flange 83 in the edge of the disk, said plate being adjustable against the tension of the springs 88 by a screW 89 extending through the flange 83 and into the body of the disk. Manifestly by adjustment of the screw 89 the eccentricity of the annulus 85 may be varied. The eccentric annulus 85 is engaged by an eccentric strap 90 carried by an arm 91 which makes pivotal connection as at 92 with a crank 93 on the shaft 33.

As the throw of the rock shaft 410 which raises and lowers the feed need not be varied an ordinary eccentric 95 on the main shaft 20 may be employed in conjunction with the eccentric strap 96 carried by arm 97 which has pivotal connection 98 with the crank 99 secured to shaft 40. As has heretofore been pointed out variation in the throw of the plunger may be taken care of by the resiliency of the torsional shaft 66, and, therefore, I may employ to actuate said shaft 66 an ordinary eccentric 100 cooperating with the eccentric strap 101 carried by arm 102. In lieu of direct connection of said arm 102 with the crank arm 103 of the shaft 66, however, I prefer to employ an intermediate bell-crank lever 101, pivoted as at 10a to the frame, having one arm pivotally connected as at 105, to the arm 102 and its other arm pivotally connected as at 106 to a link 10? which is in turn pivoted to the crank 103. The relation of these parts is preferably such that as the eccentric is passed over deadcenter with respect to its arm 102 the bell-crank 104: is thrown to approximately its upper dead-center with respect to its link 107 so that the crank 103 on the shaft 66 is elevated to its maximum extent and held in such elevated position, so as to hold the plunger at substantially its highest posi' tion, for a material length of time in the cycle of rotation of the main shaft. This insures the maintenance of the plunger in elevated position for a sufficient length of time to give adequate opportunity for the needle to penetrate the goods to be stitched, which are supported on the tip of the plunger, before the shaft 66 is rocked to withdraw the plunger-actuating crank 67 and permit the spring 63 to return the plunger to its lowest position within its carrying clamp-post. Also by properly proportioning the parts an extended range of motion may be given to the rock-shaft so that the lever 67 when withdrawn will be thrown clear out of the way of the plunger-base 61 so as to not interfere with the full depression of the feed dog and the clamp-head carrying with it the plunger.

While I have herein described in some detail a specific embodiment of my invention, it will be apparent to those skilled in the art that changes might be made in the structure without departing from the spirit of my invention and within the scope of the appended claims.

Having described my invention, what I claim is l. A sewing machine work-handling mechanism, comprising a work-handling plunger, and means to operate said Plunger including a torsionally yielding shaft.

2. A sewing machine work-handling mechanism comprising, in combination, a plunger, a movable part carrying said plunger and with respect to which said plunger has a limited range of movement, and operating means for said plunger including a torsionally yielding shaft.

3. A sewing machine work-handling mechanism comprising, in combination, a plunger, means for varying the limit of throw of said plunger, an operating means for said plunger tending to raise the same to a variable position, said operating means comprising a torsionally yielding shaft.

4:. A sewing machine work-handling mechanism, the combination with a presser foot, of a feed member, a clamp member, a plunger carried by and movable with respect to .said clamp member, yielding means normally pressing said clamp member toward the presser foot, means for imparting foreand-aft movement to said feed, means for vertically moving alternatively the feed and clamp member comprising a power-applying part, a lever acted upon by said powerapplying part having connection with both the feed and clamp member whereby either of the latter may form an abutment against which the lever may act to move the other, and means for imparting movement to the plunger to move it with respect to the clamp.

5. In a work-handling mechanism for blind-stitch sewing machines, the combination with a relatively stationary presser foot of a feed dog, a clamp cooperating therewith against the presser foot, a plunger carried by and bodily movable with said clamp, means for operating the feed dog and clamp arranged to permit their depression out of normal position during the operation of said operating means, and means for moving said plunger with respect to the clamp yieldable to accommodate the varia tions in bodily position of the plunger caused by said abnormal positions of the clamp.

6. In a work-handling mechanism for blind-stitch sewing machines, thecombination with a relatively stationary presser foot, of a feed dog, a clamp cooperating therewith against the presser foot, a plunger carried by and bodily. movable with said clamp, means for operating the feed dog and clamp arranged to permit their depression to abnormal position during the opera tion of said operating means, and means for moving said plunger with respect to said clamp comprising a rock-shaft torsionally resilient to accommodate bodily displacement of said plunger incident to the depression of the clamp. p

7. In a sewing machine, the combination with a relatively stationary presser foot having a work opening therein, a dog below said presser foot, a vertically movable clamp embraced by said feed dog, resilient means normally raising said clamp for cooperation with the presser foot, a rock-shaft provided with a crank having a fore-and-aft movement, pivotally connected with the feed dog, a rock-shaft provided with a crank having an up-and-down movement, a horizontal lever connected with the last said crank, links pivotally connected with said lever and to the feed-dog and clamp respectively, and manual means for depressing said feed dog and clamp; whereby said feed dog and clamp alternately cooperatewith the presser foot each alternately providing the abutment against which said horizontal lever may act to depress the other, and whereby both the feed dog and clamp may be moved to depressed position without interfering with the cyclic operation of the shafts.

8. In a machine of the character described, the combination with a presser foot, of work-handling means comprising in combination a feed dog, a vertically movable clamp, and a plunger within said clamp, said plunger bodily carried by said clamp and movable with respect thereto for projection above the clamp when the latter is in contact with the presser foot, two inflexible rock shafts working on fixed axes, connections between said shafts and the feed dog and clamp for imparting 4-way cyclic movement tothedog and permitting the dog to move with the clamp into operative or into inoperative planes, and means for operating said plunger with respect to said clamp comprising power applying devices and a yielding connection between the power applying devices and said plunger.

9. In a machine of the character described, the combination with apresser foot, of complemental work-handling means comprising in combination a feed gdog, a vertically movable clamp, and a plunger extending through said clamp, bodily carried by'said clamp and movable with respect thereto for projection above the clamp when the latter is in contact with the presser foot, two inflexible rock shafts working on fixed axes, connections between said shafts and the feed dog and clamp for imparting 4-way cyclic move ment to the dog and permitting the dog to move with the clamp into operative or inoperative planes and means for operating said plunger with respect to said clamp, comprising a torsionally yielding rock shaft for actuating the plunger. 1

10. In a machine of the character described, work-handling mechanism comprising a part movable between limits normally in one position, means for moving it bodily to abnormal position, and a torsionally yielding rock-shaft for imparting movement to said part in its normal position, yielding to accommodate its maintenance in abnormal position.

11. In a machine of the character described, the combination of a presser foot and complemental work handling mechanism comprising a feed dog, a clamp, means for moving said feed dog and clamp alternately toward and from the presser foot, a plunger carried by the clamp for movement therewith and movable with respect thereto, and means for moving said plunger with re spect to the clamp.

12. In a sewing machine, work handling mechanism comprising in combination a clamp, means for operating said clamp, a plunger bodily carried by and movable with said clamp, and also movable with respect to said clamp, a spring interposed between said plunger and clamp, and means for moving said plunger with respect to said clamp against the tension of said spring.

13. In a sewing machine, work handling mechanism comprising in combination a plunger, means for operating said plunger comprising a torsionally yielding shaft and a crank on said shaft cooperating with said plunger, and adjusting means for limiting the throw of said crank.

14. A sewing machine work handling mechanism, comprising, in combination with a frame, a reciprocable plunger, a crank for operating said plunger, a torsionally yielding shaft for operating said crank, and an adjusting screw for adjustably limiting the throw of said crank, extending through said frame to exposed position upon the frame.

15. In a blind stitch sewing machine, the combination with a presser foot, of a member working toward and from the presser foot to cooperate therewith in handling the goods, means to move said member, a plunger carried by said member and movable therewith and means for moving said plunger with respect to said member.

16. In a blind stitch sewing machine, the combination with a presser foot, of a member working toward and from the presser foot to cooperate therewith in handling the goods, means to move said member, a plunger carried by said member and movable therewith and means for moving said plunger with respect to said member, tending to elevate said plunger to predetermined position regardless of the position of said member.

17. In a sewing machine the combination with a presser foot, of a member movable toward and from said presser foot to cooperate therewith, means for so moving said member, a plunger carried by and movable with said member and movable with respect to said member to project therefrom through the presser foot, yielding means normally holding said plunger in depressed position with respect to said member, and means for elevating said plunger above said member while said member is elevated.

18. In a sewing machine the combination with a presser foot, of a member movable toward and from said presser foot to cooperate therewith, means for so moving said member, a plunger carried by and movable with said member and movable with respect to said member to project therefrom through the presser foot, yielding means normally holding said plunger in depressed position with respect to said member, and yielding means for elevating said plunger with respect to said member, while said member is depressed.

19. In a sewing machine the combination with a presser foot, of a member movable toward and from said presser foot to cooperate therewith, means for so moving said member, a plunger carried by and movable with said member and movable with respect to said member to project therefrom through. the presser foot, yielding means normally holding said plunger in depressed position with respect to said member, and yielding means including a torsionally resilient rock shaft for elevating said plunger with respect to said member while said member is depressed.

In testimony whereof I hereunto set my hand.

JAMES WIII'IELAW.

Witnesses:

JOHN D. RIPPEY, N.'G. BUTLER.

topics of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, I). G.

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