US843190A - Thread-guard. - Google Patents

Description

S. B. WILSON.

THREAD GUARD.

APPLIOATION FILED MAY 14, 1906.

HATENTEI) FEB. 5, 1907.

resting uponthe SARA B. WILSON, OF BUFFALO, NEW YORK.

THREAD- i specification of Letters Patent.

GUARD.

Patented Feb. 5, 1907.

Application filed May 14,1906. Serial No. 316.622.

T0 ull/ whom it may (Oil-(117711.

Be it known that I, Sana B. \VrLsox, a citizen of the United States, residing at Buftale, in the county of Erie and State of New l York, have invented a new and useful 1111- provement in 'lhread-Guards, of which the following is a specification. l

This invention relates to the guards or protectors employed in connection with the spools oi sewing-machines for preventing the thread from winding around the spool-holder i of the machine and binding or interfering} with its tension.

The object of my invention is to provide an el'licient guard of this character which can be cheaply produced.

1n the accompanying drawings, Figure 1 is a side elevation of the guard with a spool of l thread mounted thereon. Fig. 2 is a sec tional elevation thereo'l. Fig. 3 is a {ragl mentar vertical section of the guard, on an enlarged scale, in line 3, Fig. 6. Fig. 4 is a similar section in line 4 4, Fig. 6. Fig. 5 is a l side elevation of the guard with the spool omitted. Fig. 6 is an enlarged bottom plan 1 view thereof. Fig. 7 is a horizontal section in line 7 7, Fig. 5.

Similar letters of reference indicatecorresponding parts throughout the several views. A indicates the arm ol the sewing-machine, having the usual flat boss (I, and B is the spool-holder or post rising from said boss.

The improved guard comprises a base C, boss a, and a hollow or tubular post'D, extending upwardly from the base and secured centrally thereto, the base and the post looselysurrounding the spoolholder so as to be free to rotate thereon. The spool of thread E is placed upon the post and rests upon the base 0, the post being provided with means for compelling it to turn with the spool as the thread is unwound therefrom. In the preferred construction shown in the drawings the post is constructed of steel and provided with a number of longitudinal slots f, forming intervening e astic webs or tongues if, which are bulged midway between the r ends and bear against the wall of the opening in the spool with suliil grooved pulley cient pressure to ause the post, the base, and the spool to turn together. The ..slots f are preferably tapered toward their ends, so that the spring-tongues are narrowest at their middle. In order to obtain the necessary frictional contact between the spool and the post and also adapt the latter to spools with diil'erent-sized openings, the diameter of the bulged portion of the post is somewhat greater than the bore of the spool-opening, so

that the spring-tongues f are compressed more or less in passing the spool over the post and pressing it down upon the base C.- These tongues while clamping) the s 001 to the post permit the spool to e rea ily applied to and removed from the post.

The slots f terminate short of the upper and lower ends of the post, so that only the bulged central portion of the latter is free to contract up'on pressing a spool over it. This construction tends to prevent the sprin tongues f from bearing against the spoo holder and causing ends of the tongues by their connection with the solid unslotted end portions of the post sti'llening the bulged portions of the tongues and resisting their inward deflection.

The base C preferably has a concave face or groove extending from itsupper to its lower edge, giving it the appearance of a orsheave. The upper and lower edges of the base are comparativelf i sharp, so that no shoulders or abrupt edges are formed between the same andthe bottom of the spool and the flat surface of the boss'a. By this construction in case the thread drops below the spool it cannot enter between the spool and the base or between the base and the boss a and wind around the spool-holder,

but is kept away trom the latter by the con cave base.- Should the thread coil around the base, it will not become bound, but will simply unwind from it as it does from the spool, and owing to the concave form of the base the thread will naturally seek the deepest part of any tendency of the thread to work between the base and the spool or between the lower edge of the base and the boss (1.

The hollow post may be secured to the base by any suitable means. In the preferred construction shown in the drawings the sheave-like base is provided with a hub h, in which the lower end of 'the post is snugly fitted and in which it is confined against upward displacement by outwardlyturned lips 'i, formed at the lower end of the )ost and overlapping the lower side of said hub, as shown in Fig. 3. The post is held against downward displacement on the base by lugs j, projecting inwardly from the hub into notches it, formed in the ower end of the post, as shown in Figs. 4 and 6. These inbinding of the spool, the

the groove, thus counteracting 5 terlocking lugs and notches also prevent the post from turning on the base.

I claim as my invention- 1. A thread-guard comprising a base constructed to fit over a spoolholder, and a hollow post rising from the base and having longitudinal spring-tongues bulged between their ends to engage the bore of a spool and joined to the post at their upper and lower ends but terminating short of the ends of the posh whereby the ton 'ues are held against inward and outward displacement at their ends and only their bulged middle portions are permitted to contract and expand, substantially as set forth.

2. A thread-guard, comprising a base constructed to fit over a spool -holder, and a hollow post rising from the base and provided with longitudinal slots terminating short of its upper and lower .ends, forming spring-tongues which are joined to thepost at both ends, the central portions of the tongues being bulged and adapted to engage the bore of a spool, substantially as set forth.

3. A thread-guard, comprising a base conturn with said struoted to fit over a spool-holder, and a hollow post rising from the base and provided with longitudinal slots terminating short of its upper and lower ends, forming spring-tongues which are joined to the post at both ends, the tongues being tapered from their ends toward their middle and their narrow middleportions being bulged, substantially as set forth. I

4. A thread-guard, comprising a circular base constructed to turn upon aspool-holder and adapted to support a spool, said base having a concave annular iace extending from its top to its bottom, forming unshouldered edges at the upper and lower edges thereof, a hollow spool post secured to the base, and means for compelling the spool to I my hand this IOth-day of May,

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