US121328A

US121328A - Improvement in sewing-machine attachments for button-holes

Info

Publication number: US121328A
Authority: US
Publication date: 1871-11-28
Anticipated expiration: 1888-11-28

Description

' WILLIAM BURNAM.

- Improvement in Sewing Machine Attachment for working Button Holes.

No: 121,328. P atented Nov. 28,1871;

gunman UNITED STATES PATENT OEEIoE.

WILLIAM BURNAM, OF PANA, ILLINOIS.

Specification forming part of Letters Patent No. 121,328, dated November 28, 1871.

izontal section.

The invention has for its object improvement in that class of button-hole sewing-machines in which two vertically-reciprocating needles are employed in connection with other thread-carrying and locking devices; and consists in the means employed for actuating the thread-carrier that operates on the upper side of the cloth, in connection with two needles.

Referring to the drawing, a is the presser-foot, made fast to the upper part of which is a vertical bar, I), that bears against the presser-bar A in a slot, 0, in which bar is mounted a rotatory star-shaped wheel, (I, which is turned a certain distance at each rise of the needle-bar B by means of a tooth, e, pivoted at one end to the side of the needle-bar nearest the presser, which tooth, when turned down horizontally and held thus by a plate, f, fastened to the bottom of the needle-bar, strikes one of the prongs of the wheel d every time the needle-bar rises, and slips past the wheel d without turning it every time the needle-bar descends. A vertical bar, 9, stepped in the presser-foot, has a horizontal arm, h, at its upper end, which is jointed in any suitable manner to the bar Z), in such position that part of the inner end of said arm is in front of the wheel d, and the joint between the arm h and bar I) is at one side of the wheel d. The consequence is, that when the wheel d is rotated by the tooth c it turns the bar g a quarter-revolution, more or less, until the next tooth of the wheel at passesacross the end of the arm h and holds it against the force of the counter-spring i, which is coiled around the bar g. A hook-shaped thread-carrier, j, is attached to the bar g near the lower end of the same, which carrier has a loop,

70, near its rear end, and an eye near its front end, through both of which a thread, 1, passes. The thread-carrier j swings backward as the bar 9 turns, and remains in the position shown in Fig.2 during the next descent of the needle-bar, and until such time in the course of its next ascent as the tooth e strikes the wheel d, and rotates it until the tooth that holds the bar g is carried past the end of the arm h. When this takes place the spring i whirls the bar 9 around to its original position, whence it is again swung back at the next rise of the needle-bar. The swinging back of the thread-carrier at one rise of the needle-bar, and its swinging forward at the next rise, cause it to interweave its thread at every stitch with the threads of the two needles m n on the upper side of the cloth. The needle m that passes through the slit should be at least two sizes larger than the needle n that passes through the cloth, and the thread of the needle m should be larger than that of the needle 42. Both threads, however, pass through the same tension device, in consequence of which the tension on the small thread is weaker than it otherwise would be, and the smaller thread is, therefore, drawn through the cloth at every stitch so as to form a series of loops along the edge of the button-hole, for the purpose of rendering the latter more durable. The larger thread has con trol over the smaller one, and, consequently, draws it across the space between the needles on the under side of the cloth so as to form said loops. The needles m n are set in plate f, and the latter is attached to the needle-bar by a screw, so as to be removable.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

The arrangement, with presser-foot a and needles m and n, of the wheel at, bar g, spring 2', carrier j, and hinged tooth e, as shown and described, whereby they are adapted to operate in connection with said needles, as set forth.

WILLIAM BURNAM.

Witnesses:

D. O. MERRILL,

Tnos. T. Dims. 134