US72974A - Improvement in sewing-machines - Google Patents

Description

mi" raras PATENT OFFICE.

VILLIAM CHICKEN, OF CHELSEA, MASSACHUSETTS.

IMPROVEMENT IN SEWING-MACHINES.

Specification forming part of Letters Patent No. 72,9711; dated January '7, 1568.

To all whom it may concern:

Be it known that I, WILLIAM CHICKEN, of Chelsea, in the county of Suffolk and State of lVIassa-chusetts, have invented a new and useful Improvement in Button-Hole Machines; and I do hereby declare thatthe following, taken in connection with the drawings which accompany and form part ot' this specification, is a description of my invention sucient to enable those skilled in the art to practice it.

This invention is an improvement on the button-hole machine made under the United States Letters Patent granted for the invention of D. W. G. Humphrey August 29 Aand October 3, 1865, Aand now generally known as the Union Button-Hole Machine, and it relates specially ,to an improvement iu the means for rotating the disk which operates the cloth clamp or holder, to effect the feed of the work and present properly the edges of the cut in the material to the action of the stitch-forming mechanism. In said machines the cloth-clamp is moved by the conjoined action thereon of a camgroove cut in a 1otat-ing disk intermittently operating on a pin, which passes through a slot of peculiar form cut through a iiXed plate placed over said rotating disk. This disk in the Union Button Hole Machines receives its rotation from a pawl acting on ratchet-teeth cut in the edge ofthe disk the fault of this being that the disk can only be moved in rotation at each intermission an amount or angle which is determined by the act-ion of the pawl on one, two,

' or more teeth, there being no way in which the movement of the disk can be made through the space represented by any fraction of one of the ratchet-teeth.

The object ot' my invention is to remedy the defect mentioned by providing a means by which the movements of the disk may he made Whatever is desired, instead ot' being contned to Afixed divisions ot' a circle, like those of ratchet-teeth.

The drawing is a plan of a portion of the underneath surface of the top of the body or bed of a button-hole sewing-machine, from which all the parts not immediately connected with the gist of my invention are removed.

a represents the part of the body of the machine specified.

b is the rotating disk, which operates to move the cloth-clamp by a cam-groove in the Aside opposite to that shown, as in Humphreys,

`of a thickness equal tothev projection of the iian ge from the plate or web of the pinion.

On the surface of the eccentric is pivoted av lever, e, to the outer or long arm of which is hinged a curvilinear wedge, f, which tits in the L1une-like recess left between the eccentric and the flange of the pinion. On the same stud or shaft on whichl the pinion c is placed is a lever, g, the long arm of which is provided with a pin or friction-roll, It, intended to mesh into a grooved cam, by which motion'is given to the leverg, which efi'ects, through the mechanism described herein, movement ofthe disk b.

The lever e has its short arm entered into a mortise made in lever g, the mortise being' slightly larger than the enterin gend of lever e, which, consequently, is allowed a slight play or movement with respect to lever g, though subject to be moved thereby and there is xed to lever g a spring, i, which, by contact with lever c, keeps a definite relation between the two levers g and c, except when 'force enough is applied to lever e to deiiect the spring i. v

To the short-arm of lever g is, hinged, by pivot j, an arm, k, which has a capability of movement at right angles to the plane surface of the eccentric, the spring l having for its function the keeping of arm L pressed constantly toward the eccentric.

In the wedge j' there is a pin, n, the outer end of which is inclined, so as to let the arm 7c pass over the end of the pin as the arm is pressed away from the surface of the eccentric, as occurs by contact of the end ofthe arm with either of the inclined surfaces m and o.

The tendency of the spring 'i is to force thewedgef between the rim of pinion c and the eccentric d, and thus cause a frictional union between the pinion and the eccentric, that shall cause them to move together as one piece; but when the piece k is not lifted by one or the other of the inclines m or oit acts as a bar against pin n in the wedge f, and keeps the spring -from forcing the wedge tightly between the pinion-rim and the eccentric.

When the long arm of the lever g is started and moved by any suitable cam in the direction indicated by the arrow z, the arm k takes and keeps a position in 'which the pin u abuts against the side of the arm, so that the wedge cannot move with reference to said arm, and no union or binding ot` the pinion to the eccentric can take place while the long arm of g nieves in direction of arrow z.

When the cam which acts upon the long arm of the lever returns it in the direction indicated by the arrow y no turning of the pinion is effected till the arm 7c strikes one or the other of the inclines o or m and is lifted, so that spring t' can push the arm c toward arm k, and thus causes the wedge to bind together the eccentric and the pinion, so that further movement of the long arm of g in the direction of arrow y will be utilized-in partially rotating the geared cam-disk b, which operates on the cloth-clam p.

In feeding around the eye of a button-hole it is necessary to have the feed-movement considerably greater in extent than the feed-movement along the straight sides of the hole, and to effect this change inthe extent of the feedmovement automatically there is cut in the disk another cam-groove than the one before referred to, the function of which is to operate a lever7 p, so as at the proper times to throw the incline o into and ont of the path ot' the the vibration of arm It'.

The cam-groove which operates arm 19 is /l marked q, and when it operates to move the arm p and incline o into the position shown in` red lilies, then the arm It' is lifted sooner than it is when arm 19 is in the other position shown,

and the extent of feed given is that suited for The detail marked A is a cross-section taken through the disk b anda portion of the top of the bed, showing the stationary plate in which the cam-groove is cut, the plate being marked r, and the cam-groove therein s, while the cam-groove in the disk, which, in connection with cam-groove s, operates on the clothclamp, is marked t.

rlhe pinion marked u is to be rotated by a wrench by the operator, and is used onlyr for the purpose of moving the disk b independently of the regular feed mechanism, to bring back the disk to proper position for working a new button-hole after one has been previously completed.

In combination with a disk provided with gear-teeth and having a'cam for working in connection with a stationary plate-cam, as described, a pinion which meshes into the teeth of the disk, and on which pinion a frictionclamp or gripe operates to impart intermit-v tent rotative movements to said disk, for the purpose of giving movement to a stock or cloth-clamp, substantially as described.

WILLIAM oHIoKEv.

Vitnesses J1 B. CROSBY, FRANCIS GOULD.

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