US1490932A - Trimming attachment for sewing machines - Google Patents

Description

April 22. 1 924.

A. LEF'KOWITZ TRIMMING ATTACHMENT FOR SEWING MACHINES Filed June 21, 1923 Wm \f- INVENTOR.

47 (la/ton ATTORNEY Patented 11924.

13 non TRIMMING ATTACHMENT FOR SEWING IEACHINES. 7

Application filed June 21, 192?. Serial No. 6463642.

To all whom it may concern Be it known that l, AARON LEFKOWITZ, a citizen of the United States, a resident of Newark, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Trimming Attachments for Sewing; Machines, of which the following is a specification.

This invention relates to improvements in machines for stitching leather and like handles as used on portable containers of the travelling bag and suit case type.

One of the objects of the invention is to provide a device, attached to the machine on which the handle is sewn, that will trim and cut off all surplus material, parallel to the line of stitches, as the sewing progresses and without special attention on part of the operator.

Another aim is in the provision of means for sharpening the cutter, even while operating, thus maintaining a keen cutting edge, conducive to producing a smoothly severed surface upon the article cut.

These and other important purposes, such as convenience of attachment, adjustability to suit requirements, compactness and simplicity, are accomplished by the novel construction and combination of parts hereafter described and shown in the accompanying drawings. forming part of this disclosure. and in which Figure 1 is a perspective view of an embodiment of the invention, illustrating its application to a sewing machine as looking from the rear.

Figure 2 is a rear side elevational view or the same. I

In the drawing the numeral designates the raised portion of the sewing machine frame, termed a post, on the upper surface of which is secured a work support plate 11, through which the needle 12 passes.

A presser-foot 14. having a vertical stem 15 engaged by the presser foot bar (not shown), is notched or recessed at its side for the passage of the needle and has in it a relatively narrow slot 17 extending midway in its width from a point rearward and to the side of the path of the needle, into the lower portion of the stem. which is, at

that point. of rectangular cross section.

An angle bar having a horizontal flange 18 and vertical flange 19 is secured to the back of the post 10 by screws 20 passing through elongated horizontal slots 21 in the flange, and formed on the flange 18 is a transverse rib 22 engaging in a corresponding groove in the bottom of a plate 23, adjustably secured to the flange by screws 24:, the flange being slotted to permit lateral adjustment of the plate.

Carried on the upper surface of the plate 23 are a pair of spaced blocks 25 held by screws 26, these blocks acting as bearings for a spindle 27 on which is adjustably secured a cylindrical distance piece or spacer 28, filling the space between the bearings and held in adjustmentby the screw 29.

The end of the spindle, adjacent the presser-ioot, carries a disc or rotary cutter 30 having a sharply bevelled periphery and held against a hub 31 fixed to the spindle bythe enlarged head of a screw 32 so as to he clamped in operative engagement.

On the opposite end of the spindle is mounted a pulley 33 adapted to receive a belt from any convenient driving pulley, as that of a motor (not shown) and which is in nowise a part of the machine.

The extreme end of the spindle, outside the pulley 33, is flattened or otherwise suited to receive a wrench. as at 34, to hold the spindle against rotation when operating on the screw 32. A

The upper surfaces of the bearings 25 are level with or in the same plane as the work support plate 11 and it will be seen from the drawing that the cutter 30 extends into the slot 17 of the presser foot and may be adjusted centrally or to one'side thereof, and also moved limitedly forward or backward therein.

This work, as a leather bag handle, may be passed over the work support plate, below the presser foot, and as it is stitched by the needle, is trimmed at one operation, the margin being controlled by the lateral distance between the edge of the cutter and the needle.

In order to produce a smooth and neatly trimmed edge it is vitally necessary that a keen edge be maintained on the cutter and to provide for this a sharpening device is used. a

A lever-like bar 35 is pivoted by the screw ,36 to the vertical flange 19, the bar being bent upwardly at 37 and then. outwardly to provide an angular seat 38 Attached to this seat, by the screw 39, is a slotted slide 40 adjustable lengthwise the seat and having; fired at its outer end a; reac es a socket bearing 4-1 in which is a rotatable spindle 42 held by a collar 43 below the hearing.

The upper end of the spindle 42 extends above the slide and carries a bevelled abrading wheel 4 The opposite end of the lever bar 35 is extended to form a handle 45 and has fixed on it a spring arm 46 held by screws 47, this arm being bent to present a detent 4E8 engageable normally with the rear edge of the plate 23 holding the wheel 44 out of engagement with the cutter 30.

When it is desired to sharpen the cutter, the detent is raised to clear the plate, whereupon the bar 35 is turned upon its pivot 36, by action of a coiled tension spring 49, attached at its ends respectively to the bar and plate, resiliently drawing the abrading wheel 44 against the inner bevelled edge of the cutter and being rotated by frictional engagement therebetween, producing a sharp edge on the cutter in a rapid and effective manner. 7

To release the wheel from the disc it is only required to depress the handle 45. the detent 48 holding the grinding wheel in an inoperative position. 4

From the foregoing it will be seen thata simple device for this purpose has been disclosed in the preferred form of its embodiment but it is not desired to restrict the details to the exact construction shown, it being obvious that changes, not involving the exercise of invention. may be made without conflicting with the scope of the appended claims.

Having thus described my invention. what I claim as new and desire to secure by Letters Patent, is z--- l.. A sewing machine seam trimmer comprising, in combination. with the work sup port plate of the machine and presser foot thereof, said presser foot having a slot extending forward and upward from its heel portion adjacent the needle opening. of a bracket projecting rearwardly from said support plate level with the upper surface thereof. a spindle adjustable therein, a r0- tary cutter disc fixed on said spindle ope-rable in the slot of said presser foot. and means for driving said spindle.

2. A sewing machine seam trimmer comprising, in combination with the work support plate of the machine and presser foot thereof, said presser foot having a slot extend ng forward and upward from its heel port on. a cutter disc'operable in the slot, a spindle on which the disc is fixed. supports for said spindle. means for driving said spindle. means for adjusting said spindle lengthwise. and means for adjusting said supports whereby the edge of said disc 1S moved towards or from the forward end of the slot in said presser foot.

3. A sewing machine seam trimmer comprising, in combination with the work sup port plate of the machine and presser foot thereof, said presser foot having a slot e:: tending forward and upward from its heel portion, of a rotary cutter operative in the mentioned slot, said cutter being adjustable longitudinally and transversely therein, an independent drive for said cutter. and means for sharpening said cutter combined with its supports.

4. A sewing machine seam trimmer comprising, in combination with the work support plate of the machine andpresser foot thereof, said presser foot having a slot extending forward and upward from its heel portion, of a rotary cutter operative in the mentioned slot, a support for said cutter attached to said work plate, said support being adjustable. a spindle in said support upon which said cutter is detachably engaged. means for driving said spindle independently of the sewing machine. and means for sharpening said cutter during its rotation.

5. A sewing machine seam trimmer comprising, in combination with the work support plate of the machine and presser foot thereof, said presser foot having a slot extending forward and upward from its heel portion, of a rotary cutter operative in the mentioned slot, said cutter being adjustable longitudinally and transversely therein, a spindle on which the cutter is removably engaged, a support for said spindle, means for driving said spindle independently of the sewing machine, a bracket pivoted to said support. an inclined spindle rotatable in one end of said bracket, and an abrading wheel on said bracket spindle said wheel normally impinging at an angle against the periphery of said cutter.

6. A sewing machine seam trimmer comprising, in combination with the work support plate of the machine and presser foot thereof. said presser foot having a'slot extending forward and upward from its heel portion, of a rotary cutter operative in the mentioned slot, said cutter being adjustable longitudinally and transversely therein. a spindle on which the cutter is removably engaged, a support for said spindle, means for driving said spindle independently of the sewing machine. a bracket pivoted to said support. an inclined spindle rotatable on one end of said bracket, a bevelled abrading wheel fixed on the last named spindle, a spring detent carried by said bracket. and means for engaging said detent to hold said wheel in contact with the edge of said cutter in one position, and free from the cutter when in another position.

7. A sewing machine seam trimmer comprising, in combination with the work support plate of the machine and Presser foot thereof, said presser foot having a slot extending forward and upward from its heel portion, of a rotary cutter operative in the mentioned slot said cutter being adjustable longitudinally and transverselytherein, a spindle on which the cutter is removably engaged. a support for said spindle, means for driving said spindle independent of the sewing machine, a bracket pivoted to said support, an inclined spindle rotatable on one end of said bracket, an abrading wheel fixed on said spindle, resilient means for drawing said wheel and cutter into operative engagement, and a spring detent normally maintaining the wheel out of contact with said cutter.

This specification signed and witnessed this 20th day of June, 1923.

AARON LEFKOWITZ. Witnesses:

FREDK C. FISCHER, F. Now.

Images