US737358A - Ripping attachment for sewing-machines. - Google Patents

Description

PATENTED AUG. 25,1903.

No.'737,35a.

W. J. CUNNINGHAM. RIPPING ATTACHMENT FOR SEWING MACHINES.

APPLICATION FILED JUNE 2, 1902.

N0 MODEL.

are. 787,358.

Patented August 25, 1903.

PATENT OFFICE.

WILLIAM J. CUNNINGHAM, OF TOLEDO, OHIO.

RIPPING ATTACHMENT FOR SEWING-MACHINES.

, SPECIFICATION forming part of Letters Patent No. 737,358, dated August 25, 1903.

Application filed June 2, 1902. Serial No. 109,828. (No model.)

I able others skilled in the art to which it appertains to make and use the same.

My invention has reference to an improvement in ripping attachments for sewing-machines; and the object of my invention is to I produce a device of this character for attachment to sewing-machines which shall be simple, cheap, and easily operated, requiring no adjustment, being thrown into and out of operation without the manipulation of setscrews, and which is operated noiselessly without danger of injury to'the operator or to the material being ripped.

In carrying out my invention I employthe novel arrangement hereinafter shown, de-

scribed, and claimed.

Reference is to be had to the accompanying drawings, forming part of this specification, in which similar figures of reference indicate corresponding parts in all the views.

In the drawings, Figure 1 is an elevation showing my improved ripping attachment attached to a sewingmachine in position for operation. Fig. 2 is a detached elevation of the attachment, the cutter-disk and the cover 3 5 of the casing which confines the cutter-disk being removed. Fig. 3 is a longitudinal section on line w :13, Fig. 2. Fig. 4 is aface View of the cutter-disk. Fig. 5 is a similar view of the cover of the cutter-disk casing.

Referring to the drawings, 1 indicates the frame of a sewing-machine, 2 the sewing-machine table-top, and 3 the usual driving-belt, extending through an opening 4 in the table top.

My ripping attachment is mounted upon the table-top, as shown, in operative relation with the driving-belt of the sewing-machine. The attachment comprises an elongated tubular main frame 5, provided at its forward end with a flattened disk-like body portion 6, which serves as a casing for the cutter-disk, and at its to the sewing-machine table-top, a downturned lug 7 being provided upon the same adapted to be embraced between the upwardly-extending ears 8 of a plate 9, secured by means of screws to the table-top. A transverse screw 10 extends through the lug 7 and the ears 8 and secures them in pivotal relation, the main frame being capable of movement about the screw 10 as an axis, as shown in Fig. 1. At its inner end the mainframe is formed with a right-angled bend 11, and the same is extended laterally at 12. eral extension 12 is rotatably mounted the bearing portion of a groove-pulley 13, adapted to engage the driving-belt of a sewingmachine, and the same is secured to one end of a flexible shaft 14, which extends through 1 the tubular main frame,the opposil e end being secured to a bevel-gear 15, rotatably mounted in the forward end of the main frame. Both the driving-pulley 13 and the bevel-gear 15 are provided with hollow tubular extended bearing portions adapted to receive the ends of the flexible shaft 14,the latterbeing secured by any suitable means, preferably by soldering. The flexible shaft is formed by Winding a steel wire of suitable gage to form a spiral. The casing on the forward side of the frame is provided with a removable plate or cover 16, secured in position by a stud-screw 17, upon which the cutter-disk 18 is rotatably mounted, so that the latter may revolve in the space between the cover and the body of the casing, the cutter-disk being provided upon one of its faces with a bevel-gear adapted to enter the circular recess 19 in the body of the casing andengage the beve1-gear15 upon the end of the flexible shaft 14:. Both the body and the cover of the casing are provided with coincident peripheral slots, as shown at 20, the seam to be ripped being made to enter the same to be engaged by the cutting edge of the cutter-disk. Any danger of injury to the operator or to the material being worked upon is insured against by reason of the marginal flange 21, which is provided upon the body of easing at right'angles with its plane face, the cover 16 fitting snugly within the same.

The operation of my invention will be read- In the latily understood from the foregoing description, taken in connection with the drawings. The attachment is secured to the sewing-machine table-top, the groove-pulley taking a position immediately to the rear of the driving-belt. When the device is moved forward into operative engagement with the drivingbelt, as shown in full lines, Fig. 1, the groovepulley will be rapidly rotated, as will also the flexible shaft 14; and the bevel-gear 1 5, and since the gear 15 meshes with the gear upon the cutter-disk the latter will also be rapidly rotated within the casing provided therefor. The attachment is thrown out of operation by turning the same backward upon its pivot, as shown in dotted lines a, Fig. 1, when the same will be out of the Way of the operator.

It will be observed that the relative proportions of the downturned lug 7 and the pulley 13 cause the latter to rest on the machine table when the device is thrown back out of use or cause it to be drawn against the driving-belt when the device is turned forward for ripping. This I consider an improvement over former constructions for obvious reasons.

From the foregoing it becomes clear that I have provided a ripping attachment forsewing-machines which fulfils the object and aimv of my invention. The cutter disk being housed in a casing, with only a slight portion of the cutting edge exposed, there is no danger of injury to the operator or to the mate-;

rial operated upon, and since the cutter-disk is rotatably mounted at the end of the extended hollow frame of the attachment remote from the belt and other movable parts there is no danger of the material being wound around the rotating pulley or of being drawn between the pulley and the belt an inconvenience whichvcauses great loss of time. Furthermore, my invention is simple, comprising few parts, being easily operated, and requiring no adjustment whatever for its operation.

The novelty and utility of my invention-are way as not to constitute a substantial departure.

Having described my invention, what I claim, and desire to secure by Letters Patent of the United States, is r In a ripping attachment for sewing-machines, the elongated tubular main body or frame, a downturned lug at its inner end, a pivotal support on the machine-table for the lug, the frame being formed with a right-angled bend and a lateral extension near its pivoted end, a groove-pulley rotatably mounted in the lateral extension and of a size to be held'above the machine-table when in use or to rest thereon when thrown back, the diskshaped casing disposed at the outer end of the tubular frame and provided with a marginal flange at right angles to its face and a recess, a removable cover fitting within the marginal flange and held by a central studscrew, the cutter-disk rotatably mounted on said screw between the body and the cover of the casing and provided upon one of its faces with a bevel-gear adapted to occupy the recess, a bevel-gear rotatably mounted at the outer end of the main frame in operative engagement with the bevel-gear upon the cutter-disk, and a flexible shaft within the main frame connecting the groove-pulley and the bevel-gear, substantially as set forth.

In testimony whereof I hereunto affix my signature in presence of two witnesses.

WM. J. CUNNINGHAM.

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