US2667850A - Trimming attachment for sewing machines - Google Patents

Description

Feb. 2, 1954 J. GALKIN I TRIMMING ATTACHMENT FOR SEWING MACHINES 3 Sheets-Sheet 1 Filed Dec. 16, 1952 FlG.l

JOSEPH GALKIN INVENTOR ATTORNEY Feb. 2, 1954 I J. GALKIN 2,667,850

TRIMMING ATTACHMENT FOR SEWING MACHINES Filed Decf16, 1952 s Sheets-Sheet 3 Patented Feb. 2, 1954 UNITED STATES PATENT OFFICE TRIMMING ATTACHMENT FOR SEWING MACHINES This invention relates to trimming mechanism for sewing machines; and particularly to that type of trimming mechanism wherein a movable cutting blade passes up and down through the work support of the sewing machine, and by cooperation with a fixed blade substantially level with the work support, trims the fabric which is being seamed.

In such trimming mechanism as heretofore constructed, when operating on soft fabric, the trimmed selvage material cannot push the trimmed selvage material ahead of it and the machine gets clogged up and the selvage gets caught and packed behind the heel of the movable blade and makes the machine inoperative.

Instead of attempting to push the chips rearwardly over a fiat horizontal work supporting base, this attachment guides the chips downwardly and forwardly of the machine.

This attachment comprises a chip guard or guide trough having a wall which extends slightly to the rear of the movable cutting blade and terminates in a downwardly and forwardly extending inclined guide wall which guides the selvage trimmings forwardly and so that the trimmed selvage material falls down at the front of the machine due to its weight.

This attachment relates particularly to sewing machines designed for attaching an elastic tape to woven fabrics such as the waistbands of bloomers to permit the waist portion to stretch to the required size.

In prior art it was necessary to fold the edge of the garment fabric. The stitching passed over the folded edge and covered the edge.

With the attachment herein disclosed, the waistband edge of the garment fabric is trimmed just prior to the stitching operation. The stitching passes over and conceals the trimmed but unfolded edge. The resulting seam is flat and of less thickness than the prior edge-folded seam.

This invention is particularly directed to an improved trimming attachment wherein the movable cutting blade is actuated from below the work supporting base of the sewing machine and the main object of this invention is to provide an arrangement of mechanism whereby the base is free of upstanding brackets and the operator can clearly see the materials being fed to the needles and this results in improved quality of workmanship.

Another object of this invention is to provide a movable chip guard fixed to a movable blade carrier and at the upper surface of a movable blade and movable up and down with the blade while slightly inside the fixed chip guard, the movable chip guard having an upright extension sloping forwardly and causing the chips to move forwardly and fall into the fixed chip guard which facilitates their sliding out'from the machine.

This application is a continuation in part of my now abandoned patent application, Serial No. 33,114, filed June 15, 1948, and a continuation in part of. my now abandoned patent application, Serial No. 57,950, filed November 2, 1948.

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 fragmentary top plan view of a work supporting base of a sewing machine embodying the invention.

Figure 2 is a front elevation of a fragmentary portion of the Work supporting base portion of the sewing machine shown in Figure 1.

Figure 3 is a fragmentary top plan view of the work supporting base shown in Figures 1 and 2, and including a modified and improved trimming mechanism.

Figure 4 is a front elevation of a fragmentary portion of the trimming mechanism shown in Figure 3.

Figure 5 is a cross-sectional view taken on line 55 in Figure 3, and showing nested chip guards.

Figure 6 is a view similar to Figure 5, without the chip guards.

Figure 7 is a cross-sectional view taken on line 1-1 in Figure 3 and showing a dual guard arrangement.

In the illustrated embodiment of the invention, shown in Figures 1 and 2, the numeral Ill indicates a work supporting base of a sewing machine, comprising a base plate ll, two spaced needles [2, and a presser-foot I3, resting on a needle plate l4 secured to the work supporting base l0.

Projecting through the needle-plate I4 is a work advancing feed-dog [5 having actuating mechanism (not shown) but which may be of the usual four-motion type of feeding mechanism.

The feed-dog i5 is opposed by the presser-foot l3 having its shank I6 suitably secured to the lower end of a presser-bar ll vertically movable in the head of the sewing machine in the usual manner.

The needles l2 are secured in a needle-bar i8 vertically movable in the head of the sewing machine. Cooperating with the needles I2 below the work supporting base 10 is an oscillating looper (not shown). The looper thread interlocks with the needle threads to form two needle interlock stitching.

driven. v The trimming mechanism comprises a cutting blade 2| fixed to the work supporting base In and which lies parallel to the line of stitching and with its cutting edge atthe upper level of the work supporting base H). j j

A cooperating movable cutting blade 22 is carried by a slotted head 23 at one end of a rod 24.

27. A coil spring 28 mounted on the rod 24 and compressed between a slidable collar 29 and the bearing 26, urges the movable blade 22 in yieldable cutting engagement with the fixed cutting blade Zl. The collar 29 is bifurcated and engages the rocker arm 21 and prevents rotation of the rod 2 3.

The rocker arm 21 is fixed to a rod 30 rockably mounted in brackets 3|, 32 fixed to the base platel I. The rocker arm 2'! is oscillated through a link 35 fixed to the rod 30 and through a strap arm 35 from an eccentric 36 at one end of the main shaft 20.

The movable cutting blade 22 is of arcuate form and its lower end or heel portion coacts with the fixed cutting blade 2| to trim the righthand edge of. fabric fed by the feed-dog It: to the needles I2.

In order to positively clear the blades of the trimmed selvage and prevent clogging of the blades I provide a chip guard 3i having a vertical wall 38 extending slightly to the rear of the heel of the movable blade 22.

At the lower end of the vertical wall 38, the guard 37 extends forwardly and downwardly as defined by an inclined wall 40. The work supporting base ID has a covered opening 4| and the presser-foot has a transverse opening 42 in front of the needles to permit the guard wall 38 to extend upwardly therethrough and terminate slightly above the work-supporting base H1. The lowermost edge of the chip guard 31 extends outwardly beyond the work supporting base I and delivers the trimmed selvage clear of the sewing machine. The guard 3'! is fixed to the base plate II by screws 43.

Figures 3 .to '7, inclusive, show a modified and improved trimming mechanism 50.

As shown in Figures 3 to 7, inclusive, the numeral l0 indicates a fragmentary portion of the work-supporting base of the sewing machine shown in Figures 1 and 2.

The sewing machine shown in Figures 3 to '7, inclusive, comprises the base plate 1, two spaced needles I2 and a presser-foot l3 resting on a needle-plate M.

Projecting through the needle-plate I4 is the work advancing feed-dog l5 having actuating mechanism of the usual four-motion type.

The feed-dog I5 is opposed by the presser-foot I3 having its shank l6 secured to the lower end of the presser-bar ll vertically movable in the head of the sewing machine in the usual manner.

The needles l2 are secured in the needle bar l8 and cooperate with an oscillating looper |9 to form two needle interlock stitching.

The main shaft 20 is journaled in the base portion ll of the machine and drives the stitch forming and feeding elements.

The improved trimming mechanism 5|) comprises a cutting blade 2| fixed to the work supporting base l0 and which lies parallelto the The rod 24 is slidably'mounted in spacedapart bearing portions 25, 26 of a rocker arm 4 line of stitching and with its cutting edge at the upper level of the work supporting base I0. 7 The improved trimming mechanism 50 comprises a carrier plate 5| positioned below the work supporting base l0 and a shaft carrying bracket 52 which is adjustable with the carrier plate. The bracket 52 has an elongated keyshaped extension 53 positioned parallel with the shaft 5%. The carrier plate 5| has a keyway 55 into which the key-shaped extension 53 is slidably mounted. A screw 56 is threaded in a lug 51 which extends downwardly from the carrier plate 5|. A screw 66 passes through an elongated slot 6| in the carrier plate 5! and is threaded into the extension 53. It is thus possible by means of the screws 56 and B0 to adjust the bracket and the blades in desired relation to the carrier plate so that the blades 2| and 62 are in ore-determined spaced-apart relation from the needles. of the trimmed seam.

The cooperating movable cutting blade 62 is carried by a rocker arm or movable blade carrier 63 fixed to the shaft 5 4. The shaft 52 is rockably mounted in a bearing 65 extending from the bracket 52.

The rocker arm 83 is oscillated through a link 66 fixed to the shaft 55 and through a strap arm 6? from an eccentric 68 on the main shaft 2%.

The movable blade 62 is substantially C-shaped, and at its upper portion it oo-acts with the fixed cutting blade 2i to trim the right-hand edge of the fabric fed by the feed-dog E5 to the needles 12.

A coil spring 58 mounted on the shaft 54 and compressed between a thread nut 59 and the bearing 65 urges the movable blade 62 in yieldable cutting engagement with the fixed cutting blade 2|. 7

In order to positively clear the blades 2| and 62 of the trimmed selvage and prevent clogging of the blades while maintaining a clear upper surface of the Work supporting base It, I provide a main chip guard 69 which is fixed to a supplemental portion N3 of the work supporting base It by screws 7|. The chip guard 69 has a substantially vertical guard wall 72 extending slightly to the rear of the cutting blades.

The chip guard 69 has a forwardly and downwardly' inclined wall 13 which terminates at the front face of the base A supplementary guard plate or cover plate 75 is fixed in upright position to the base by screws 76.

A further chip guard ll is secured by a screw 14 to the movable blade carrier 63 and has an upright side wall i8 which is bent downwardly. The chip guard ll has a vertical and forwardly curving guard wall is following the C-shape of the movable blade 62.

The work supporting base I83 has a through covered opening 36 and the presser-foot 13 has a transverse opening 82 in front of the needles to permit the guard walls 72 and it to extend upwardly therethrough and terminate slightly above the work-supporting base Hi.

The lowermost portion of the chip guard 69 extends outwardly beyond the base plate II and delivers the trimmed selvage clear of the sewing machine.

As shown in Figures 4 and 5, it will be seen that by actuating the shaft 54 by a transverse link 66, that an unobstructed opening 85 is provided insthe front portion of the base and in alignment with the main chip guard $9.

The trimmed selvage is thus constrained to move sideways through the transverse opening This adjustment controls the width 7 82 in the presser-foot E3, downwardly over the upright wall 19 of the further chip guard 11 and then forwardly over the wall 13 of the main chip guard 69 and entirely clear of the forward face of the sewing machine base I l.

The arrangement disclosed makes possible continued operation of the sewing machine because the selvage or chips cannot reach the working parts inside the base H and are further kept away from the upper surface of the work supporting base l0 and automatically delivered outside the machine, which was not possible heretofore.

An important improvement of this modified attachment over attachments heretofore in use, is that the stationary blade 2| is integral with a slidable bracket 52 carrying the shaft 54.

The result is that both blades may be moved simultaneously to the right of the needle to increase the amount of fabric left at one side of the needles for strength, etc.

In accordance with the patent statutes I have described and illustrated the preferred embodiment of my invention, but it will be understood that various changes and modifications can be made therein without departing from the spirit of the invention as defined by the appended claims.

I claim:

1. In a trimming attachment for a sewing machine having a needle, comprising a work supporting base, a presser-foot, a cutting blade fixed to said work supporting base, a cooperating movable cutting blade carried by a movable blade carrier and actuated from a horizontal shaft rockably mounted directly below said work supporting base, a main chip guard fixed to said work supporting base and having a rearwardly and upwardly inclined wall terminating in a guard wall positioned slightly to the rear of said cutting blades and forming an unobstructed opening at the front portion of said base and to one side of said needle, a further chip guard fixed to said movable blade carrier and facing downwardly into said main chip guard and having a rear upright guard wall, said work supporting base having a portion removed providing a through opening to permit said vertical guard walls to extend upwardly above said work supporting base, said presser-foot having a transverse opening permitting said movable cutting blade to pass upwardly therethrough, and means for actuating said rock shaft from beneath said work supporting base to thereby leave said front opening unobstructed and in coaction with the needle and with said main chip guard, whereby selvage trimmings from said cutting blades may move downwardly through said transverse opening in said foot, downwardly over said upright guard wall of said further chip guard and then forwardly over said inclined wall of said main chip guard and discharge entirely clear of the forward face of said sewing machine base.

2. In a trimming attachment for a sewing machine having a needle, comprising a work supporting base, a presser-foot, a bracket slidably mounted below said work supporting base, a cutting blade fixed to said bracket, a co-operating movable cutting blade carried by a movable blade carrier and actuated from a horizontal shaft rockably mounted directly below said work supporting base, a spring pressing against one end of said shaft and causing said fixed and movable cutting blades to be in tensioned cutting relation, a main chip guard fixed to said work supporting base and having a rearwardly and upwardly inclined wall terminating in a guard wall positioned slightly to the rear of said cutting blades and forming an unobstructed opening at the front portion of said base and to one side of said needle, a further chip guard fixed to said movable blade carrier and facing into said main chip guard and having a rear upright guard wall, said work supporting base having a portion removed providing a through opening to permit said vertical guard walls to extend upwardly above said work supporting base, said presser-foot having a transverse opening permitting said movable cutting blade to pass upwardly therethrough, and means for actuating said rock shaft from beneath said work supporting base to thereby leave said front opening unobstructed in its co-action with said needle and with said main chip guard, whereby selvage trimmings from said cutting blades may move downwardly through said transverse opening in said foot, downwardly over said upright guard wall of said further chip guard and then forwardly over said inclined wall of said main chip guard and discharge entirely clear of the forward face of said sewing machine base.

3. In a trimming attachment for a sewing machine having a needle, comprising a work supporting base, a presserfoot, a bracket slidably mounted below said work supporting base, a cutting blade fixed to said bracket, a co-operating movable cutting blade carried by a movable blade carrier and actuated from a horizontal shaft rockably mounted directly below said work supporting base, a spring pressing against one end of said shaft and causing said fixed and movable cutting blades to be in tensioned cutting relation, a main chip guard fixed to said work supporting base and having a rearwardly and upwardly inclined wall terminating in a guard wall positioned slightly to the rear of said cutting blades and forming an unobstructed opening at the front portion of said base and to one side of said needle, a further chip guard fixed to said movable blade carrier and facing into said main chip guard and having a rear upright guard wall,

said work supporting base having a portion removed providing a through opening to permit said vertical guard walls to extend upwardly above said work supporting base, said presserfoot having a transverse opening permitting said movable cutting blade to pass upwardly therethrough, and means for actuating said rock shaft from beneath said work supporting base to thereby leave said front opening unobstructed in its co-action with said needle and with said main chip guard, whereby selvage trimmings fromsaid cutting blades may move downwardly through said transverse opening in said foot, downwardly over said upright guard wall of said further chip guard and then forwardly over said inclined wall of said main chip guard and discharge entirely clear of the forward face of said sewing machine base, said slidable bracket permitting both said blades to be jointly moved sideways of said needle to vary the amount of fabric left at the trimmed edge of the fabric. JOSEPH GALKIN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,016,590 Weis Feb. 6, 1912 1,048,204 Onderdonk Dec. 24, 1912 1,353,534 Hughes Sept. 21, 1920

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