US2197496A - Pinking and stitching machine - Google Patents

Description

April 16, 1940.

J. GALKIN, 2,197,496

PINKING AND STITCHING MACHINE Filed Aug. 31, 1938 3 Sheets-Sheet 1 Q o I I O I I IF 1' P all I!" I} f m 13 1% Z* 0 1 1 I m m I ll W ATTORNEY.

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Tl Q16; 3% v 43 53 JOSEPH GALKIN 5 I INVENTOR. 4 42 RPM April 16, 1940. .LGALKIN 2,197,496

I YINKING AND STITCHING MACHINE Filed Aug. 31, 1938 3 Sheets-Sheet 2 ATTORNEY.

April 16, 1940. GALK|N 2,197,496

PINK-ING AND STITCHING CHINE Fi led Aug. 31, 1938. a Sheets-Sheet s JOSEPH GAL KIN INVENTOR.

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Patented Apr. 16. 1946 UNITED STATES PATENT OFFICE 5 Claims.

This invention relates to sewing machines and particularly to a sewing machine provided with a rotary pinking wheel whereby the work may be simultaneously stitched and pinked.

An object of this invention is to provide a rotary trimming unit comprising an upper positively rotated rotary cutting element mounted in fixed bearings and a lower freely rotatable and vertically movable roller cooperating therewith.

Another object of this invention is to cause a pressure against the lower rotary element by a spring supported in the bed of the sewing ma chine and to transmit the pressure against the upper rotary cutting element.

Another object of this invention is to provide mechanism for mounting the rotary trimming unit in cooperating relation with a sewing machine having an oscillating loop taker actuated in parallel relation with the main actuating shaft.

Another object of this invention is to provide a pinking mechanism operating in conjunction with a sewing machine making two needle interlock stitching with a looper and without the necessity of repeatedly rewinding a bobbin.

Another object of this invention is to provide a combined trimming and stitching machine having a four-motion feed mechanism and a. rotary trimming mechanism and means for independently adjusting said mechanisms in timed relation.

With the above and other objects in view, the invention will be hereinafter more particularly described, and the combination and arrangement of parts will be shown in the accompanying drawings and. pointed out in the claims which form part of this specification.

Reference will now be had to the drawings, wherein like numerals of reference designate corresponding parts throughout the several views, in which:

Figure 1 is a front view of a sewing machine having the improved pinking mechanism embodied therein.

Figure 2 is a front view of the pinking mechanism on an enlarged scale.

Figure 3 is an end view of the sewing machine, showing the pinking wheel positioned rearwards of the needles a distance sufiicient to permit the transverse looper to move rearwards of the needles.

Figure 4 is an enlarged end view of the pinking mechanism installed in the sewing machine, the sewing machine frame being broken away and shown diagrammatically.

Figure 5 is a cross-sectional view, the section being taken as on line 5-5 in Figure 2.

In the illustrated embodiment of the invention, the numeral It indicates a combined pinking and stitching machine comprising a bed ll having a main actuating shaft l3 rotatably mounted therein. The bed I l comprises a work supporting base l3. The machine comprises the usual standard M having an overhanging arm [5 with a head l6 at its free end. In the head i6 is journalled the usual reciprocatory needle-bar I! carrying needles l8. Theneedle-bar is reciprocated by a lever l9 mounted on a pivot shaft 20.

A looptaker 2i is oscillated and cooperates with the needles to form straight line interlock stitching as is well known in the sewing machine art. The material worked upon is held down by a presser foot 22 resting on a cloth plate 23 secured to and above the work supporting base I3.

The presser foot 22 is pivotally connected to a presser foot shank 24 by means of a pin 25. The shank 24 is secured to a presser bar 28 which is secured by a transversearm: 21 to a guide bar 26. Aleaf spring 39 mounted in the head It is pressed down by a screw 3|. The leaf spring 30 bears on an arm 33 secured to the upper end of the presser bar 28. The presser bar 28 may be raised by means of a lever 29. The spring pressure on the presser bar 28 is transmitted through the arm 21 to the guide bar 26 and the presser foot 22. It is to be noted that the presser foot 22 is designed for vertical sliding motion concomitantly with the feed dog 32, and that it also has a pivotal motion about the pin 25, and this pivotal mounting provides for rocking motions of the presser foot when passing over cross-seams.

The pinking mechanism 35 comprises a pinking wheel 36 which cooperates with a roller 31, the outer periphery of which extends through an opening in the cloth plate 23 slightly above said plate. The pinking Wheel 36 is rotatably mounted on a shaft 38. The shaft 38 is fixed in a bearing .39 integral with a housing plate 4!] which is fastened to the bed II. The roller 3'! is freely rotatably mounted on a roller stud 4| fixed at one end of a lever 42. The lever 42 is pivotally mounted on. a pin 43 at the rear portion of the lower face of the housing plate 40.

In order to hold the roller 31 in tensioned cutting relation against the outer periphery of the pinking wheel 35, I have provided a spring 48 which presses at one end against the lever 42 and at the other end against an extension 50 in the bed II and this pressure is transmitted to the pinking wheel 36. An adjusting screw 49 threaded in the extension 58 of the bed H reacts against the spring 48 and forces the roller 31 against the pinking wheel 36 and provides means for regulating the pressure therebetween.

A lock nut 5| serves for locking the screw 49 after adjusting. This adjustment of the screw 49 is such that the tension between the wheel 36 and roller 31 is sufiicient for cutting through as many as six or eight superposed layers of cloth or other fabric.

As many as eight layers of fabric have been cut through by the pinking mechanism herein disclosed on cuffs attached to sleeves of dresses.

The thread carrying looper 2| is oscillated to give a needle avoiding movement thereto. Due to the oscillating looper motion whereby the looper passes successively in the front and in the rear of the needles, the pinking wheel has been mounted at the rear of the needles a distance sufficient to clear the looper in its rearward motion. The looper or loop-taker 2|, shown in Figure l, is a conventional threaded looper of the fourmotion type cooperating with the needles, having its needle loop engaging and disengaging movements in a line transverse to the line of feed and its needle avoiding movements in the line of feed as shown in Patent No. 1,619,436.

The stitching mechanism comprises one thread carrying looper and two needles. The two needles are closely spaced together so that the needle threads are only about one-thirty-second of an inch apart. The looper thread cooperates with the needle threads to form interlock stitching. The line of stitching is somewhat stretchable and will not rip up under conditions which cause lockstitch stitching to rip.

In the art of pinking with a rotary wheel having triangular cutting surfaces on its periphery in pressure engagement with a smooth surfaced roller, it has been found very difficult to align the axes of the wheels in perfectly parallel relation. When the axes are misaligned, the cutting is not performed uniformly, with the result that the pinked edges are frayed and not completely separated. When the bearing surfaces of the wheels become worn, the misalignment and imperfect cutting becomes more evident.

In the structure shown herein, I do not depend for perfection in pinking on the parallel relation of the shafts for the rotary cutting members. As shown in Figure 2, the shaft 38 on which the pinking wheel 36 is mounted, is of comparatively small diameter and has furthermore been mounted in overhanging relation so as to permit the pinking wheel shaft to give or yield slightly. I have provided an arm 52 secured axially of the bearing 39 and carrying two rollers 53, 53, mounted in equally spaced relation on each side of the shaft 38. The rollers 53, 53 press on the outer periphery of the clutch casing 54 very close to the pinking wheel 36 and maintain the rotary pinking members in adjusted cutting relation and in contact all along the width of the pinking members.

The rollers 53, 53 are designed to maintain the pinking wheel 36 in a positively fixed upper horizontal plane. The rollers are carried by a transverse arm 63 mounted on a pivot 64 and contact the clutch casing and relieve the pressure on the pinking wheel shaft.

As shown in Figure 2, the arm 52 has been secured in an opening at the upper surface of the bearing 39 by a screw 65 threaded into the metal of the bearing. Two screws 66, 66 have been threaded into the arm 52 and seat against the lower surface of the opening. By manipulating the screws, it is possible to adjust the contacting relation between the rollers 53, 53 and the clutch casing 54 and thus bring the pinking wheel 36 into parallel relation with the pinking roller 31.

For the purpose of imparting positive rotary step-by-step driving motion to the pinking wheel 36, I employ an oscillatable clutching detent carrier 55 mounted with coacting rollers 56 and springs 51 within the casing 54, shown in Figure 5. The arm58 has been fastened to the clutching detent carrier 55. The arm 58 is pivotally connected at one end to a crank arm 59 which is operated by an eccentric 68, secured to the main shaft I2. The swing of the arm 58 imparts an intermittent rotation to the casing 54 and through screws 44, shown in Figure 4, to the pinking wheel 36.

As shown in Figure l, a swinging frame 6 I, pivoted at 62 forms the front portion of the work supporting base I3. The frame 6| may be swung forwardly to permit thread-control for the looper thread.

By actuating a screw 61, Figure 3, a crank 68 is caused to move to or away from the center of the shaft l2, and causes an arm 69 to impart a larger or smaller swing to the stub shaft 10. The feed bar 12, carrying the feed dog, is pivotally connected to the upper end of a rocker H which is pivotally mounted at its lower end to the frame of the machine, an arm 69 which is rigid with the rocker being actuated to impart feed and return strokes to the feed dog, there being other means not shown to impart to feed bar 12 and feed dog 32 rising and falling movements around the pivotal connection at 16. It is to be noted that the arm 58 is slotted to provide adjustability of the pivotal connection between parts 58 and 59 for increasing or decreasing the throw or step-by-step movement of the pinking wheel 36. It is to be further noted that the arm 58 and the detent carrier 55 which is fixedly secured to the said arm, are freely oscillatable on the shaft 38. This pivotal connection constitutes means for adjusting the movements of the pinking wheel independently of the movements of the feed dog of the sewing machine.

As best shown in Figure l, the presser foot 22 has a transverse extension 44 in front of the pinking wheel 36 and this extension presses down the material to be pinked and causes it to be fed to :he wheel 36 in a flat and non-wrinkled condilOIl.

It is to be noted that the outer periphery of the rollers 53 are arcuate, that the transverse arm 63 carrying the said rollers is movably mounted on the pivot 64 and that the arm 52 is angularly adjustable by the screws 65 and 66. These features make it possible to bring the pinking wheel 36 into parallel relation with the pinking roller 31.

The clutch detent carrier 55, rollers 56 and springs 51 may be in the form shown and described in Patent No. 1,985,406 issued to Nathan B. Galkin, dated December 25, 1934.

As shown in Figure 4, a coil spring 4| has been positioned between the lever 42 and the leaf spring 48. The spring 4| provides a resilient support for the free end of the spring 48.

I claim:

1. In a sewing machine having a bed and a main actuating shaft therein, an oscillating looper adapted for movement transverse of the line of stitching and cooperating with a plurality of needles to form interlock stitching, a work supporting base supported by said bed, a shaft fixedly mounted above said work supporting base. a pinking wheel freely rotatably mounted on said shaft, a clutch casing freely rotatably mounted on said shaft and being secured to said pinking wheel for rotating said wheel, an arm having one end rotatably mounted on said shaft and being connected with a detent carrier in said clutch casing, said arm being in engagement at its other end with an eccentric on said main shaft, whereby an oscillatory movement is imparted to said clutch for driving said pinking wheel step-by-step, and means for adjusting the movements of said pinking wheel independently of the adjustment of the movements of the feed dog of said sewing machine.

2. In a sewing machine having a plurality of needles and a bed having a main actuating shaft therein, an oscillating looper adapted for movement transverse of the line of stitching forward and rearward of the needles, said looper being adapted to cooperate with a plurality of needles to form interlock stitching, a work supporting base supported by said bed, an overhanging shaft supported in a bearing above said work supporting base, a pinking wheel freely rotatably mounted on said shaft at the free end thereof, a clutch casing secured to said pinking wheel and being freely rotatably mounted on said shaft, an arm overhanging from said bearing and carrying two rollers, said rollers being equally spaced apart on opposite sides of said shaft and being in engagement with the upper portion of said casing adjacent said pinking wheel, said rollers being adapted for holding said pinking wheel in position, a rotary member pivotally mounted for vertical movement below said pinking wheel, means for bringing said pinking wheel and said lower roller into tensioned cutting relation, and a connection between said main shaft and. said clutch for rotating said pinking wheel, said pinking wheel being positioned rearward of said needles a distance sufficient to clear said looper in its motion rearwards of said needles.

3. In a sewing machine having a plurality of needles and a bed having a main actuating shaft therein, an oscillating looper adapted for movement transverse of the line of stitching forward and rearward of the needles, said looper being adapted to cooperate with a plurality of needles to form interlock stitching, a work supporting base supported by said bed, an overhanging shaft supported in a bearing above said work supporting base, a pinking wheel freely rotatably mounted on said shaft at the free end thereof, a clutch casing secured to said pinking wheel and being freely rotatably mounted on said shaft, an arm overhanging from said bearing and carrying a plurality of pivotally mounted rollers, said rollers being spaced apart on opposite sides of said shaft and being in engagement with the upper portion of said casing adjacent said pinking wheel, said rollers being adapted for maintaining said pinking wheel in a positively fixed upper horizontal plane, a rotary member pivotally mounted for vertical movement below said pinking wheel, means for bringing said pinking wheel and said lower roller into tensioned cutting relation, and a connection between said main shaft and said clutch for rotating said pinking wheel, said pinking wheel being positioned rearward of said needles a distance sufficient to clear said looper in its motion rearwards of said needles.

4. In a sewing machine having a bed and a main actuating shaft therein, a work supporting base supported by said bed, an overhanging shaft supported in a bearing above said work supporting base, a pinking wheel freely rotatably mounted on said shaft at the free end thereof, a clutch casing secured to said pinking wheel and being freely rotatably mounted on said shaft, an arm overhanging from said bearing and carrying a plurality of pivotally mounted rollers, said rollers being spaced apart on opposite sides of said shaft and being in engagement with the upper portion of said clutch casing, said rollers being adapted for supporting said pinking wheel in a positively fixed upper horizontal plane, a rotary cooperating member pivotally mounted for movement below said pinking wheel, means for bringing said pinking wheel and said lower rotary cooperating member into tensioned cutting relation, a connection between said main shaft and said clutch for rotating said pinking wheel, and means for adjusting said overhanging arm for alining said pinking wheel with said rotary cooperating member.

5. In a sewing machine having a bed and a main actuating shaft therein, a work supporting base supported by said bed, a shaft supported above said work supporting base, a pinking wheel freely rotatably mounted on said shaft at the free end thereof, a clutch casing secured to said pinking wheel and being freely rotatably mounted on said shaft, an arm fixed to said work-supporting base and carrying a plurality of rollers, said rollers being spaced apart on opposite sides of said shaft and being in engagement with said clutch casing, said rollers being adapted for supporting said pinking wheel in a positively fixed upper horizontal plane, a rotary cooperating member mounted for movement below said pinking wheel, means for bringing said pinking wheel and said lower rotary cooperating member into tensioned cutting relation, a connection between said main shaft and said clutch for rotating said pinking wheel, and means for adjusting said arm for alining said pinking wheel with said rotary cooperating member.

JOSEPH GALKIN,

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