US242296A - Albin gaeeett and eufus thomas - Google Patents

Description

(No Model.)

A. GARRETT & R. THOMAS.

Trimming Attachment for'sewing Machines.

No. 242,296. Patented May 31,1881.-

1 Y FIG 1,

UNTTED STATES PATENT OEErcE.

ALBIN GARRETT AND RUFUS THOMAS, F PHILADELPHIA, PENNSYLVANIA, ASSIGNORS TO THE NATIONAL SEWING MACHINE COMPANY, (LIMITED,)

OF SAME PLACE.

TRIMMING ATTACHMENT FOR SEWING-MACHINES.

SPECIFICATION forming part of Letters Patent No. 242,296, dated May 31, 1881.

Application filed November 22, 1880.

To all whom t't may concern Be it known that we, ALBIN GARRETT and Burns THOMAS, citizens of the United States, residing in Philadelphia, Pennsylvania, have invented certain Improvements in Sewing-Machine Attachments, of which the following is a specification.

Our invention relates to improvements in the shears connected with sewing-machines for the purpose of trimming the edges of the fabric simultaneously with the stitching of the same; and the objects of our improvements are, first, to afford facilities for the accurate adjustment'of the vibrating blade ofthe shears, I 5 and, second, to allow the fabric to pass freely onto the cutting-edge of the lower blade.

In the accompanying drawings, Figure l is a plan view of a sewing-machine from which part of the structure has been removed to illustrate our invention; Fig. 2, a perspective view of the shears and devices through the medium of which one of the blades is operated from a crank-pin on the driving-wheel of the machine; Fig. 3, a transverse section on the 2 5 line 1 2, Fig. 1; Fig. 4, a detached perspective view of the fixed blade of the shears; Fig. 5, a view of the pivot for the upper blade; Fig. 6, a detached view of the recessed work-plate, drawn to an enlarged scale; and Fig. 7, a sec- 0 tional view, also enlarged, and showing the relation of the fixed blade of the shears to said recessed work-plate.

As far as the sewing-machine itself is concerned, it maybe similar to an yof the machines 3 5 in common use, and is provided with the usual needle-bar, presser-foot, and feed mechanism.

To the bed-plate A of the machine is secured a plate, G, made longitudinally and laterally adjustable, preferably by elongated slots,

through which set-screws less in diameter than the width of the slot pass into the bed-plate.

From the adjustable plate G projects the lower blade, 71, of the shears, the upper blade consisting of the short arm '1; of a lever, H,

which is pivoted at w to the plate G, and the long arm of which has a slot to receive and guide the sliding blockF, through which passes a portion of the pin K, Fig. 5, the other portion of the pin passing through an elongated (No model.)

slot in an arm, M, and being secured thereto by a nut, so that the pin can be adjusted on the arm to any extent which the desired position of the upper blade of the shears may demand. The arm M is secured to one end of a shaft, N, which has its bearings in suitable boxes or lugs on the under side of the bedplate A, and on the opposite end of the shaft is an arm, P,connected, by a link,T, to a crankpin, 10, on the driving-wheel of thesewingmachine. The lever H is comparatively loose on its pivot, and a spiral spring, (I, on the portion m of the pin K has a continuous tendency to force the long arm of the lever H outward in the direction of the arrow, Fig. 1, and to press the upper blade of the shears against the fixed blade at and near the point, thereby insuring the efficient shearing action of the two blades.

The cutting-edges of the blades are in such a position in respect to the needle and the needle-hole in the work-plate that as the fabric is being stitched and fed its edges will be properly trimmed ,the distance from the stitches to where the trimming takes ett'ect on the fabric being regulated by the adjustment of the plate G on the bed of the machine.

On referring to Figs. 6 and 7 it will be seen that the work-plate S is recessed at u, so as to form a shoulder, 'l ,the lower blade of the shears resting in this recess, and the point of the blade bearing against the shoulder, Fig. 7. This arrangement allows the fabric to pass freely onto the cutting-edge of the lower blade, and permits the formation on this blade of a comparatively blunt point, on which the fabric cannot catch. By this means we are enabled to trim much closer to the seam than can otherwise be doue, and the upper blade of the shears is at liberty to pass the lower blade up to the extreme point of the latter without coming into contact with the work-plate. The upper blade should admit of very nice adjustment, so that the shears may exert the proper cutting effect to the extreme point, and this adjustment can be readily cfi'ected by shifting the pin K in the slot of the arm H.

We claim as our invention- 1. The combination of the fixed blade of the shears, the upper blade forming part of the lever H, the sliding block F, adapted to guides in the lever, the vibrating slotted arm M, and the pin K, made adjustable in the said arm and adapted to the sliding block, all substantially as set forth.

2. The combination of the lower fixed blade of the shears with a work-plate, S, having a recess, v, adapted to the said blade and terminating in a shoulder, y, against which the end of the blade abuts, all as set forth.

3. lhe combination of the lower blade of the shears, having a blunt end, with the work-'

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