US1424706A - Sewing machine - Google Patents

Description

C. M. ABERCROMBIE. SEWING MACHINE.

APPLICATION FILED DEC.26, 1919.

11,424,706. at nted Aug. 1, 19.?2.

2 SHEETS- -SHEET l INVENTOR 6% a ZasM afercramie,

ATTORNEY c. M. ABERCROMBIE.

sawme MACHINE. APPLICATION FILED DEC.26, 1919-. 1,424,706. Patented Aug. 1, 1922.

2 SHEETS-SHEET 2.

WITNESSES:

INVENTOR CizarZesflfoZercrmzz'g v BY m ATTORNEY onannns ABERCROMBIE, or BRIDGEPQBT, connnorrcnr, nssrenon TO THE srnenn MANUFACTURING con rast, on ELIZABETH, NEW JERSEY, A con.-

PORAKLION on NEW JERSEY.

SEWING MACHINE.

Specification of Letters Patent.

Patented Aug. 1, 1922.

Application filed December 26, 191 9. Serial No. 347,311.

To all whom may concern Be it known that 1, CHARLES M. ABER- CROMBIE, a citizen of the United States, re: siding at Bridgeport, in the county of Fairfield and State of Connecticut, have invented certain new and useful Improvements in Sewing Machines, of which the following is a specification, reference being "had therein to the accompanying drawings.

This invention relates to improvements in needle-actuating mechanism for sewing machines and particularly for hemstitch sewing' machines, although well adapted for improving the ordinary zigzag-stitch sewing machines.

in needle-bar actuating mechanisms of the zigzag-stitch class, after extended operation thereof, the wear of the parts-permits a slight axial oscillation and uncertain amplitudeof lateral vibration of the needle-bar sufficient to mar the appearance of the seam due in a large measure to irregular penetration of the work bythe needle. It is par ticularly essential in producing hemstitch figures to obviate staggering stitches on the seam line of the hem-fold to effect a more sightly product. A large variety of needle vibrating mechanismshave heretofore been constructed, all of which lack features essential in closely approximating an ideal hemstitch figure.

An object of this invention is to provide an improved construction for pivotally supporting the needle-carrying bar whereby lateral movements may be imparted to the needle in a manner obviating the difficulties heretofore encountered.

Another object of this invention is to provide an improved pivotal support for the needle-carrying bar at a point remote from the needle whereby in hemstitching operations the distortion of fabrics is obviated and the stitching is more uniformly located to enhance the appearance of the hemstitch figure.

A further object of this invention is to adequately guide the needle carrying bar in its vertical-reciprocatory and bodily-lateral movements in a simple manner to obviate marring of the seam by looseness of the parts under constant wear.

The invention also comprehends the combination of this improved needle-bar actuating mechanism with one or more piercers assisting in the formation of a hemsbitch figure. I

Other objects of the invention will be apparent from the following description and claims.

In the preferred embodiment of the present invention the ordinary needle-bar of a sewing machine is employed as a piercer-carrying bar and is vertically reciprocated in the usual manner. Mounted upon the piercerbar is a collar provided with oppositely directed extensions, the forked end ofone of which embraces the usual presser-bar to prevent axial rotation of the piercer-bar. The other extension sustains a flat spring suitably secured to the upper end of a needlecarrying bar, which byspecially constructed means is guided in ways to permit vertical reciprocation with the piercer bar and lateral vibration independently thereof. The particular advantage derived from the, flatspring pivotal support of the needle-bar in hemstitch sewing machines is that it tends to cause the needle to pierce the material in a uniform seam line on the hem-fold, producing a more pleasing product. This is obviously also true in ordinary zigzagstitching machines.

In the accompanying drawings, Fig. ,1 is a view in front side elevation and partly in section of a sewing machine embodying the present invention. Fig 2 is a view in front end elevation of the same, certain parts being broken away to better illustrate the mechanism. Fig. 3 is an enlarged detail view partly in section of the piercer-bar guiding and needle-bar carrying collar. Fig. 4 is a sectional View substantially on the line ww, of Fig. 2. Fig. 5 is a sectional View substantially on the line y-y, of Fig. 2. Figs. 6 and 7 are respectively side and rear details in elevation of the needle-bar guiding and piercer-supporting bracket. Fig. 8 comprises detail perspective views of the piercer supporting and needle-supporting and guiding elements.

Inasmuch as the present invention may be embodied in any suitable sewing machine,

and as it relates more particularly to the needle and piercer supporting and actuating mechanlsm, only such reference Wlll. be made to the sewing machine elements, asis deemed necessary fora comprehension of the inven ftion.

ed-to drive the loop-taker 8. A fabric feed-' dog 9 is as usual carried by the feed-bar 10,

supported and actuated in 'a well known manner by the rock-shafts 11 and 12 to effect one backward and two forward feedmovements'for each hemstitch'figure. A feed-dog actuating mechanism of this character is clearly-disclosed and described in my prior Patent No. 1,271,256, issued July 2, 1918.

At its forward end, the driving shaft 51s provided with the usual'shaft-flange 13 carrying the crank-pin 14 pivotally embraced guided by the slideway 20. formof thread take-up mechanism may be by the hub on one end of the link 15'of which the opposite'end engages in a like manner the pin 16 projecting from the collar 17 suitably secured upon theibar 18, in the present instance termed the piercer-bar; The piercerbar18 is journaled for endwise reciprocation I in suitable bearingsprovided in the head 4,

and is held against axial oscillation-by the slide-block 19, carried by the pin 16 and Any suitable employed and such construction is accord- 'ingly omitted from the drawings for the sake of clearness of illustration. The usual bearings are provided for the presser-bar 21 permitting end-wise movement of the latter to raise and lower the presser-feet QZand 23, which are supported in a well known manner by thepresser-bar to yield independently of each other to different thicknesses of work.

Secured by means of a screw 24 upon the lower end of the piercer-bar 18, is the tubular shank 25 of a transverse supporting plate 26. At one side ofthe piercer-bar, there is secured upon the supporting-plate 26, by means of a screw: 27, a righteangled piercer-carrying bracket 28. It: will be observedfthat the bracket-28 is providedonits rear side with a rib entering a groove in the face of the platef26, so that the single screw 2'? amply secures the bracket in position. The bracket 28' is provided with 'vertical apertures in the horizontal portion thereoffso that one or more piercers may be carried thereby. In the present instance only one piercer 29 is employed, the laterally offset shank 30 of this piercer being secured in the bracket 28 by means of asst-screw 31. In case a second piercer is, employed, it is held in place by 65 means of a set-screw 32.

Clamped upon the piercer-bar 18, by means of a screw 33, is a split-collar 34 provided with oppositely directed extensions, the forked end 35 of one of which slidingly engages the presser-bar 21't0 further insure that the piercer-bar and the collar 34 are held against axial movement. To the other 8X- tension 36 of the collar 34 is secured a flat spring 37 by means of a screw 38'and' a reinforcing plate 39; Secured by means of a screw 40 and reinforcing plate 41 upon the spring 37 in spaced relation'with respect to the extension36 is the flattened portion of a collar 42 fastened upon the upper end of a needle-bar43 by means of a set-screw 44. The needle-bar 43, by means of the described connections, 'is caused to reciprocate vertically with the piercer-bar 18 and is securely guarded againstaxial oscillation by the extension 35, theslide-block 19, and the resistance offered by the flat spring 37.

The mounting of the needle-bar upon the fiat-spring 37 also permits lateral movements of the lower end of the needle-bar. To adequately guide the needle-bar in its lateral movements, the upper end of a vibrating guide-bar 45 is pivotally mounted upon a stud 46 projecting laterally from a lug 47 on the machine frame and afiording a bearing for the upper end. of the :piercer-bar. A screw 48 serves to maintain-the guidebar uponthe stud ,46.- The direction of movement of the guide-bar is limited by the provision thereon of a guide-lug 49 snugly fitted for sliding movement within a guideway 50 formed in a bushing 51, suitably secured in an aperture in the head 4 and 'aifordinga lower bearing for-the pijercer-bar.

At its lowerend the guide-bar 45 is provided with an. aperture 52 affording. a ournalfor the needle-bar 43 in its endwise reciprocatory movements. A boss 53 on the guidebar is pivotally connected by means of'a screw 54 with the forward end of a pitman 55 which the other end is suitably connected with, a vibratory lever56 fulcrumed upon the machine frame and actuated in a well known manner by means of a cam 57 geared to the driving shaft 5., Secured by means of a, screw 58 .tothe lower end of the needle-bar is a block 59 formed with an aperture 60 entered by a guide-stud 61 held in place by means of a set-screw 62. The guidestud 61 enters a slot 63 formed in the supporting plate 26, whereby the head of the stud and the rear wall of the block, 59 together form a slideway insuring a right line horizontal component of-movement of the block 59. Sufficient clearance is provided be; tween the shank of the guide-stud 61 and the walls of the slot 63 to permit of the slight arcuate movementof the block 59 occasioned p by the spring connection between the piercerbar and the needle-bar as described. A depending portion 64 of the block 59 is provided with a transverse groove in which is adjustably secured, by means of a screw 65, a needle-carrier 66 formed with a socheted lug 67 entered by the shank of a needle 68 secured in position by means of a setscrew 69.

From the foregoing description it is apparent that the needle 68 receives endwise reciprocating and bodily lateral movements; that ample provision is made to maintain the needle in the desired paths of movement, w-ithal in a simple manner, and that the piercer 29 is limited to endwise movements. In operation, the needle and piercer-cooperate in a well known manner in the formation of hemstitch figures, with distinct advantages arising out of the present improved manner of supporting and actuating the same In hemstitch sewing machines wherein the needle-bar is fulcrumed closely adjacent the needle, and particularly in high speed machines of this character, the abrupt angular movements of the needle frequently causes merely a distortion of the fabric instead of a deflection of thefabric threads. Further, in machines wherein the needlebar is journaled for reciprocation in a swinging gate, the lateral movements of the needle do not have the necessary wedge action to deflect the threads properly. In the present construction, by pivotally supporting the needle-bar at a point remote from the needle, a medium of the former extremes is obtained conducive to the best results. The flat spring support for the needle-bar is not subject to the wear inherent in the pivotal supports for needledoars of prior construction and consequently serves to maintain a more uniform seam-line during continuous use. Further, the fiat spring continuously tends to remain untorsioned thereby serving, in connection with the lateral-movement guideways described, to constantly maintain the eye of the needle in the desired direction with respect to the loop-taker conplemental to the needle in the formation of stitches.

Having thus set forth the nature of the invention, what I claim herein is 1. In a sewing machine, in combination, an ai'l-tuating shaft, a reciprocating needlebar, a needle carried thereby, operative connections intermediate said actuating shaft and said needle-bar including a flat spring support for the latter forv imparting vertical reciprocatory movements to the needle, a vibratory guide in which said needle-bar .is journaled for endwise reciprocation, and means for positively vibrating said needlebar laterally upon said flat spring support.

2. In a sewing machine, the combination with a reciprocating needle-bar, a needle carried thereby and an actuating shaft, of a reciprocatory actuating bar, a piercer carried by said actuating bar, a fiat-spring connection between the actuating bar and the needle-bar affording a vibratory support for the latter, a vibratory guide for the needlebar, and means for vibrating said guide to impart lateral movements to the needle.

5. In a sewing machine, the combination with a reciprocating needle-bar, a needle carried thereby, and an actuating shaft, of a piercer-bar, a piercer carried thereby, a fiat spring connection between the piercer-bar and the needle-bar affording a vibratory support for the latter, means for reciprocating the piercer-bar, and means for vibrating said needle-bar laterally upon its vibratory support.

a. In a sewing machine, the combination with a reciprocating needle-bar, a needle carried thereby, and an actuating shaft, of a reciprocatory piercer-bar, a guide bracket sustained by the piercer-bar affording a guide for the needle-bar, a fiat-spring connection between the piercer-bar and the me die-bar affording a vibratory support for the latter, means for reciprocating said piercer-bar, and means for vibrating said needle-bar laterally upon its vibratory support.

5. In a sewing machine, the combination with a needle-bar, a needle carried thereby, and an actuating shaft, of a reciprocatory piercer-bar, a flat-spring connection between the piercer-bar and the needle-bar affording a vibratory support for the latter, a guidebracket sustained by the piercer-bar affording a guide for the needle-bar, a vibratory guide for the needle-bar, and means for vibrating said guide to impart lateral movements to the needle.

6. In a sewing machine, in combination, a needle-bar, a needle carried thereby, a piercer-carrying bar, means for pivotally supporting said needle-bar upon said piercer carrying bar at a point remote from the needle whereby the needle-bar is movable laterally in a straight path, guiding means for the needle-bar adjacent the needle, means for reciprocating said piercer carrying bar whereby endwise reciprocatory movements are imparted to the needle, and means for vibrating the needle-bar laterally.

7. In a sewing machine, the combination with an actuating shaft, a reciprocatory bar, and operative connections between said shaft and said bar, of means for restraining said bar against axial oscillation, a collar secured upon said bar, an extension upon said collar affording further restraining means against axial oscillation of said bar, a needle-bar carried by said reciprocatory bar, a needle carried by the needle-bar, and

a jeurnal for said needleharindependent of said reciprocatory bar.

8. In hemstiteh sewing machine, in combination, a piercer-bar, means for recipro- "tti g the piercer -bar, a supporting plate earned byszud plercer-bar, a plereer susmined by the supporting plate, a needlebar,' means for endwise reciprocating and laterally vibrating said'needle-bar, a guidebloek carried by the latter, and coacting with said. supporting plate to guide the needlebar in its hteml movements, and aneedle adjustably sustained by said guide-b10ck.

In testimony whereof, I have signed my name to this specification.

CHARLES M. ABERCROMBIE.

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