US303818A

US303818A - Machines

Info

Publication number: US303818A
Authority: US
Publication date: 1884-08-19
Anticipated expiration: 1901-08-19

Description

(No Model.)

B. D. CUMMINGS.

TRIMMING DEVICE FOR SEWING MACHINES. No. 303,818.

Patented Aug. 19, 1884.

INVENTOR 2M ATTORNEY WITNESSES i /6MZM UNITED STATES PATENT Fries.

EVLYN D. CUMMINGS, OF NEl/V YORK, N. Y.

TRIMMING DEVICE FOR SEWING-MACHINES.

SPECIPICATICN forming part of Letters Patent No. 303,818, dated August 19, 188%.

(No model.)

To all whom it may concern.-

Be it known that EVLYN D. Centuries, of the city, county, and State of New York,

have invented a certain new and useful In1- provcment in 'lrinnning Devices for Sewing- Machincs; and I do hereby declare that the following is a full,'clear, and exact description and specification of the same.

The object of my improvement is to increase the eflieicncy of an ordinary sewing-machine trimming attachment by providing means for counteracting the effects of wear and maintaining the knife in its most effective position. As the trimming attachment is well known and described in nun'ierous patents, I have simply shown in the drawings, and will proceed to describe, a throat-plate of an ordinary sewing-machine, (in this case the Singer 0scillator,) and the knife, which is attached in the usual manner to a vertically-reciprocating bar.

In the drawings, Figure 1 is a top view of such a threat, showing the application of my adjusting slide. Fig. 2 is a side view of the same, showing the cnttingknife at its highest position. Fig. 3 is a sectional view of the throat through the line a b, Fig. 1; and Fig. 1 is an edge view of said knife.

This knife comprises a cutting-edge, c, and a guiding-stem, d. hen in operation the guidingstem (Z enters and works in the notch c of the slide A, and the eutting-edge descends through the slot f, between said slide and the threat. The cuttingedge c is beveled on the side nearest to the slide A, and the cutting is done by said cuttingedge operating against the fixed side of the throat f.

In cutting attachments of this character the practical difiiculty has always been to keep the vibrating cutting-edge close up to the fixed opposing edge or surface, so as to operate steadily and effectively against it; and to overcome this difficulty I have provided the positive adjustable slide A, provided with the setscrew B, having a space, G, Fig. 3, (made round for convenience and oheapncss of lnanufacture,) so that it can be moved up as the stem or beveled edge of the knife wears away, thus maintaining the cutting-edge of the knife in firm, positive, and efficient contact with the fixed edge or surface against which it operates.

I claim as my invention- In a sewing-machine trimming attachment, the combination, with a reciprocating trim.- ming-knife having a guiding-stein and a cutting-edge, of a throat-plate having a recess, a slide adjustable in a right line in said recess, and having a notch for the said guiding-stein, whereby the wear of said knife may be compensated for by adjusting said slide to bring the cutting-edge of the knife in close contact with the cooperating side of the throat-plate, substantially as set forth.

EVLYN D. CUMMINGS.

itnesses:

CHAS. ELKIN, llllARK DUNNELL.