US273562A

US273562A - Thomas a

Info

Publication number: US273562A
Authority: US
Publication date: 1883-03-06
Anticipated expiration: 1900-03-06

Description

(No Model.)

T. AQMAOAULAY.

TENSION RELEASE FOR SEWING MACHINES.

No. 273,562. Patented Mar-.6,1883.

N ITED STATES PATENT OFFICE.

THOMAS A. MAGAULAY, on NEW YORK, N. Y.

T ENSlON-RELEASE FOR SEWING-MACHINES.

SPECIFICATION forming partof Letters Patent No. 273,562, dated March 6, 1833.

Application filed August 18, 1881. (No model.)

To all whom it may concern:

Be it known that I, THOMAS A. MAGAULAY, of the city, county, and State of New York, have invented an Improved Tension Device for Sewing-Machines; and I do hereby declare that the lollowing is a full and exact description thereof, reference being had to the accompanying drawings, making part of this specification.

ln removing the sewed fabric or article from asewing-machine. the usual practice is, first, to pull 011' from the tension a sufficient length of thread to enable the fabric to be withdrawn without drawingupon the thread, after which withdrawal to cut the thread. of pulling the thread against the force of the tension often breaks the thread, and if the fabric should be drawn any farther than the length of thread previously set free there is again aliability to break the thread. By my improved tension device the tension may be released without strain or injury to the tension-spring, thereby allowing the thread to be pulled freely from the spool while removing the fabric from the machine, and without breakage.

In theaccompanyingdrawiugs,Figure 1 represents a side View of my improved tension device as applied to the arm ofa sewing-machine; Fig. 2, a similar view, butshowing the parts of the tension device in position for releasing the tension, and thereby allowing the fabric to be withdrawn from the machine without hinderance from thetensi'on and without liability to break the thread; Fig. 3, a top view, and Fig. 4 an under side view, of the notched and 4 hinged tension-plate which forms one part of my invention; Fig. 5, a top view of the tensionplates and their adjuncts.

Like letters designate corresponding parts in all of the figures. I

Let A represent a portion of a sewing machine arm on which my improved tension device is mounted. An upper spring or elastically-yielding tension-plate, B, of any suitable form or construction, is secured to a boss or'projection, a, of the arm A by a thumbscrew, 0, the rear end of said plate bearing on another boss or projection, b, of the arm, while the other end of the plate presses down upon a counter-plate, D, between which and the This operation in releasing the tension.

spring-plate the thread passes in the usual way, and is compressed with the requisite force to produce the proper tension by the thumb-screw G pressing down the middle of the plate, there being sufficient space between the plate and the attaching-boss a to allow all the downward curvature and pressure ever required. The lower or counter plate, D, is hinged or pivoted to another projection, c, of the arm A by means of cars or bearings ff, through which the pivot-pin 9 extends, as well as through theprojection c,as shown, or otherwise, in a suitable or equivalent manner. One of the ears or bearingsf is extended downward, as at d, (or a suitable projection otherwise extends down from the plate,) and is preferably bent round into a nearly horizontal 'POSltlOYl-, as shown, suitable for reaching to and moving by the hand of the operator. The forward edge of the plate D is suitably rounded or curved, assindicated, to allow the plate, as it is rocked on its pivot, to bear upward against the spring-plate B and lift it somewhat, as shown in Fig. 2; and this edge of the plate D is notched, as shown in Figs. 3 and 4, at h, so that when the plate is turned into the position for lifting the plate 13, as shown in the said Fig. 2, the thread lying centrally over the said plate D will be'in the notch thereof, and consequently be entirely free from pressure and tension, the adjacent pressure-surfaces of the two plates then being separated. Thus at the time no impediment is offered to the drawing of the thread from its spool. On let ing go the handle-projection d the springpressure of the upper plate, B, immediately brings back the two plates into parallelism and thread-compressing position, as shown in Fig. 1.-

In this as would be in any spring tensionrelcase it is important that a limit be placed to the extent to which the spring is retracted l have eftected this purpose, and have represented, in connection with my tension-release, a stop, 1, which limits the downward movement of the handle-lever d. Fig. 2 shows the said lever as depressed into contact with the stop, and of course it cannot be depressed any farther, and so no undue strain can come on the spring-plate B.

Any unessential changes inthe foregoing construction may be made, provided the essential device and its proper operation be retained. This application is a renewal and direct continuance of a part of my application for improvements in sewing-machines filed March 8, 1880, No. 4,539, and struck out of said application by amendment of-even'date with the filing of this application, as required by the Gommissioners decision.

What I claim as my invention, and desire to secure by Letters Patent, is-- 1. In a sewing-machine tension, the combination of apivoted notched tension-plate, D, with a spring"counter-plate, B, and a suitable device for tilting the notched plate D to release the thread from tension, substantially as and for the purpose herein specified.

2. The combination of the pivoted notched tension-plate D, provided with the handle-lever d, the counter-plate B, and screw 0, substantially as and for the purpose herein specified. 3. The combination of the pivoted notched tension -plate D, provided with a handle. d, spring: counter-plate B, and a stop, i, to limit the movement of the plate D, substantially as and for the purpose herein specified.

4. In combination with a counter-tension plate, B, a. pivoted or rocking tension-releasing plate, I), provided with ineans,in connection with the said counter-tension plate, for permitting the release of the thread, and with a handle for operating the said releasing-plate,

substantially as and for the purpose herein with means, in connection with the said counter-tension plate, for permitting the release of the thread, and with a handle for operating it to release the thread, for the purpose Herein specified. p

7. in combination with acounter-tension device and a projection, c, the pivoted tensionplate, D, having a lever, d, for operating the plate to release the thread, substantially as and for the purpose herein specified.

8. A lever tension-plate adapted for use with a counter-tension devicc,and having a handle for operating it to release the thread, substantially as and for the purpose herein specified.

9. In combination with a counter-tension device a lever tension-release plate and astop to limit the movement of the same, substantially as and for the purpose herein specified.

10. A tension-release plate having wings ff and handle d, pivoted to a support. 0, in combination with a counter-tension plate and regulating device, substantially as and for the purpose herein specified.

11. In combination, a tension-release plate provided with a handle-lever, a counterten sion plate, and a regulating device, substantially as and for the purpose herein specified.

12. [n a sewing-machine tension, the combination of a notched' tension-release plate with a counter-tension plate and a regulating device, suhstantiallyas and for the purpose herein specified.

13. A tension-release adapted for use with THOS. A. MAOAU LAY.

Witnesses:

J. S. BROWN, D. P. UowL.