US131735A - Improvement in sewing-machines - Google Patents

Description

.Mrnrrr OFFICE l. nnANKLINH-BRCWN, 0F CHICAGO, ILLmols.`

IMPROVEMENT IN SEWING-MACHINES.

Specification forming part of Letters Patent No. 131,735, dated October 1, 1872.

` To all whom it may concern:

Be it known that I, FRANKLIN H. BROWN,

` of Uhicago,'0ook county, andV State of Illinois,

have invented new and useful Improvements in Sewing-Machines;` and I do hereby declare that the following is a-full, clear, and exact description thereof, which will en able those skilled y taken at the dotted line a' :c of Fig. l, and viewed in the direction indicated by the arrow; and Fig. 3 is a detail top view of the feeding mechanism. y

Likeletters indicate like parts.

My invention relates to `sewing-machines, and consists in a novel method of regulating the position of the feed-bar so far -as its height is concerned, to' enable the operator to raise or lower the same with ease and dispatch preparatory to sewing upon heavy or light goods; a novel arrangement of parts to act as a takeup77 for the needle-thread. y

In the drawing, `A represents the bed-plate of the machine, which also serves as a frame to which-to attach certain other parts'of the machine. B B is the neck. C is the vibratory arm. i D is the head of the machine. E and E' are pendantsor lugs cast on the under side of the bed-plate, in which lugs the shaftF has its bearin gs. G is a swinging or vibrating bar, operated by an eccentric upon the shaft F to actuate the feed-bar P. His a iiexible bridge fastened to plate K by any suitable means, under which bridge the lever I is passed, and, by. the friction occasioned by the contact and pressurebf these several parts, the lever is held in any desired position under the bridge, for the purpose of insuring the formation of stitches of a uniform length, the length of the stitch depending upon-the position of the fulcrum y in the slot a. When the fulcrum y is placed low down in slot z the stitch will be long, but-when it is raised to the upper part of the slot the stitch4 will be short; therefore the `stitch may be graduated to any desired length between the two extremes by placing the fulcrurn y in any desired intermediate position in the slot a, and it will be retained in any such position by friction occasioned by the pressure of the bridge upon lever I. In other words,

the position of the lever I may be changed and held in any desired'position without manipulation further than simply raising or lowering the same. E is abearing for the forward end of the main shaft F, and arranged behind the face-plate K andthe feed-actuating mech- The feed-bar P anism. fr R t is a bent lever. l is pivoted to the vibratory arm t of said lever,

shown in Figs. 2 and 3, arm t being rigidly aty `tached to the part R working in a bearing through the upper end of the bar G, and held in position by means of therod r, which is also rigidly attached to the part R, and is controlled at its outer end by the plate l, through which it passes and Works. The rod sis fastened directly to the feed-bar P for the'purpose of sup-v porting'it as it moves in a horizontal plane.

When sewing thick or heavy goods the feedbar P should be raised and made to act above the bed-plate much higher than will be necessary when sewing light or thin goods, and to enable the operator to graduate and regulate the position of the feed-bar with reference to the bed-plate so far as its altitude is concerned,

I support the end of the arm r freely in an opening in plate Z. The vertical part m of plate lis provided with a screw-pin, a, which projects through the slot of the pendant p. o is a thumbscrew run upon the pin n for the purpose of holding the piece l in any desired position. By loosening nut o the position oftlie plate lmay be changed, thus making the adjustment referred to. u is a pin projecting horizontally from the head D, and providedwith a perforation through which the thread is passed. This perforation is arranged at a point sufficiently distant from the head of the pin to prevent the slack thread from becoming entangled or broken by the end of the pin u. c and c are open loops attached to the vibratory arm C, and preferably made iieXible, and in form substantially as shown, so that the thread may be readily placed therein by pressing it over theends of the loops instead of the difficult process of passing the en d of the thread through the eyes formed by the loops. a a is a vertical rod attached to a post projecting from the 'rear of the head D, and is provided with a'vertical slot sufficiently wide to receive the thread. The rod a is provided with a spiral spring surrounding it. The thread f passes from the tension device o through the perforation in the post u, from thence into the loop c', and into the vertical slot in the post or rod a; from thence it is carried upward and suspended by the loop o from which it is carried through the eye of the perforating-needle.

It will be observed that in the operation of sewing the slotted rod a operates in connection with the post u, loops c c', and spiral spring w as a take-up7 device. a is an ex tension of the rod a, and forms a shoulder upon the same to support the spiral spring, and extends far enough downward to prevent the slack thread at this point from becoming entangled or broken about the lower end of the extension a. One sideof the slot iu rod ais made flexible, so that it Awill readily open to admit the thread f and retain it therein, as shown at b, Fig. 1.

In my former improvements in sewing-machines the front bearing of the main shaft has been in the face-plate between the shuttlecarrying disk and the feed-actuating mechanism. My present improvement relating thereto consists in removing the bearing from the face-plate and placing it back of the feedin gmechauism in an independentbearin g there arranged. By this improved arrangement Iv 1. The feed-bar P and the supporting and guidingrod s, in combination with the lever r R t, havinga bearing in the bar Gr, and pivoted to the feed-bar P.

2. The plate l m, provided with a screw-pin, n, in combination with the slotted pendant p andthumb-screwo, for the purpose of adjusting the lever 1^ R t and regulating the feed-bar P, substantially as specified.

3. The rod a, provided with a. sprin g or tongue, b, constituting a slot therein, and also provided with a spiral spring, lw, in combination with loops o and c', and post u, substantially as and for the purposesvspecied.

FRANKLIN H. BROWN Witnesses:

F. F. WARNER, N. C. GRIDLEY.'

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