US98390A - Improvement in sewing-machine - Google Patents

Description

T. LAM B.

Sewing Machine.

- V2 Sheets-Sheet 1. l.

n. FETERS. Mwwnwr. Washington DJ;

2 Sheets-Sheet 2. T. LAMB.

Sewing Machine.

Patent-ed Dec. 28, 1869.

tnited Cie-taten :me aan.

kLette/rs Patent No. 98,390, dated December 28, 1869.

IMPRVEMENT IN SEWING-MACHINE.

' The Schedule referred to in these Letters Patent and making part of the same ATo all whom fit 'may concern Be it known that I, THOMAS LAMB, of Philadelphia, Pennsylvania, have invented certain Improvements in Sewing-Machines; and Ido hereby declare the following to be a full, clear, andrexact description o f the same.

My invention consists of' certain improvements, fully described hereaften'in that class of lock-stitch sewingmachines, in which discoidal shuttles are used.

In order to enable others skilled in the art to make and usc my invention, I will now proceed t0l describe its construction and operation, reference being had to the accompanying drawing, which forms a part of this specification, and in which- Figure 1 is a longitudinal sectional view lof' my improved sewing-machine 5 Figure 2, an end viewof the same;

Figure 3, transverse section on the line 1 2, fig. 1,

looking in the direction of the arrow;

Figure 4, a plan View, showing the edge ofthe shuttie;

Figures 5, 6, and 7, detached views, illustrating my' invention; and

Figure S, a modification.

Similar letters refer to similar parts throughout the different views. e

A is the base-plate of the machine, in projections a c, beneath which turns the driving-shaft B, the latter being provided, near its rear end, wit-h an eccentric, C,

by meansv of which, and an arm, X, shown by dotted' lines in iig. 1, the necessary reciprocating motion is imparted to the needle-arm D.

At the front end ofthe shaft B isa forked -driver, c, by which the discoidal shuttle F is rotated, the latter being arranged at an angle, as shown in iig. 1, and turning in an inclined race.

.'lhis shuttle-race consists of two plates E and E, each of which is curved so as to fit against and enter a groove of the shuttle, the two plates being secured to a hanger, M, which projects at` an angle from the underside of the base-plate.

In consequence of the inclination of the shuttle-race, the prongs of the driver, as they rotate, alternately enter and are withdrawn from holes b b on the face of the shuttle, neither ot' them being in permanent contact with the latter, and offering no obstruction to the passage of the'loop of needle-thread around the shut tie, as will be more fully described hereafter.

The nose or hook el of the shuttle is formed by cutting away a portion ot' the circumference ofthe same, as clearly shown in ig. 4, and, secured to the centre of the inner face of the shuttle, by a screw o'r otherwise, isv an adjustable projection or hook, e, having, at its outer end, a bevelled edge, e', for a purpose described hereafter4 At the upper end of the plate E of the shuttle-race is a bevelled project-ion, f, the object of which is to push the loop of needle-thread over the hook d, and to direct it to each side of the shuttle, as shown in fig. 2.

. A rod, h, is secured to the plate E of the race, and

projects over a portion of' the inner face of the shuttle,

and on the opposite side of the shuttle is a recess for the reception of a bobbin, G, which, in the present instance, is held invits place by a plate or case, i, the edge' of which tits loosely in a groove in the` shuttle, the case, however, not turning with the latter.

The shuttle-thread from the bobbin G passes through one or more openings i in the plate i, according to the tension required.

The presser-foot H is attached to one end of a recessed arm, I, which is curved in the arc of a-circle, and secured, at its opposite end, to a plate, J, the latter being arranged to turn upon trunnions jj of the base-plate, and being elevated, at its rear end, by a spring, k, which tends to hold the presser-foot down to the work-plate l.

The feeding-dog K is also secured to a curved arm, L, which is arranged to slide in the recess m of the arm I.

A lug, p, is attached to the needle-arm D by a setscrew, or otherwise, so that it may readily be adjusted thereon, and is arranged, when the needle-arm is raised, to strike a pin, qfg. -7, which enters the vvrecess m of the arm I, and has secured to it, within the said recess, a wedge-shaped block, q'.

One side of this block q bears against theinclined end of the arm L, and its opposite side against the i11- clined end of a plate, r, which is slotted, and has a slight motion within the recess m, limited by a pin, o".

A spring, s, of the arm I, rigs. 2 and 3, bears against one side ot' the feeding-dog arm, andtends to push it from the recess m, the feed being ePected bya lateral pressure in the opposite direction, imparted by a lever, t, which is hung to the arm I.

The lever t is provided with a curved arm, t, which partly embraces the needle-arm, so that when the latter is raised, a pin, u, ofthe same, shall strike and turn the arrn t', causing the lever t to bear against and operate the feed-dog K.

Operation.

When the needle descends through the fabric to be sewed, and toward the shuttle, the hook d of the latter passes between the needle and its thread, and carries the loop toward the bevelled projection f, which, as befere mentioned, pushes the loop back on to the hook d, and directs it Vto each side of the` shuttle, as

seen in iigs. 2, 3, and 4.

The shuttle continues to revolve, carrying the loop with it, and the' needle descends to the lowest point,

and again rises until it is entirely,witlidrawn from the cloth, as shown in fig. 5, at which time the presser-foot H is raised, and the feed-dog K depressed and moved laterally to a sufficient extent to eiect the desired change of position of'the cloth.

These motions of the presser-foot and feed-dog are eiected simultaneously, as the needle is raised, by the lug p and pin u of the needle-arm, as I will now pro ceed to explain.

The lug p strikes the pin q, and forces the wedgeshaped block g into the recess on' of the arm I, the block bearing upon and causing the plate r and arm J to move in the direction of their respective arrows,

rlhe motion of the plate r is arrested by the pin r',

the plate J then turning upon its trunnions j untilthe arm I is moved suliiciently to raise the presser-foot Y clear of the cloth, as shown in iig. 2.

.llhe arm L is in the mean time moved'iu a contrary direction, causing the feed-dog to bear upon the cloth. l

As soon as these motions are perfected, the pin u Yof theneedle-arm` strikes the arm t of the lever t, and

causes the latter to bear upon and move the feed-dog laterally to the required extent.

When the needle again descends, the block q' is again released, and the spring k of the plate J bears upon the bed-plate, turns the arm I, and depresses the foot H until it again bears upon the cloth.

At the same time the pin u descends, releasing the lever t, and permitting the feed-dog to regain its former position by the action of the spring s. (See g. 3.)

As the needle descends through the cloth a second time, the irst loop is thrown oli' from the shuttle by the bevelled edge e ofthe hook e, as shown on fig. 6, and the loop, when thus detached, is prevented from becoming entangledwith the driver C by the rodjl,

which holds it close to the shuttle.

As the needle continues to descend, a second loop is caught by the shuttle-hook, and carried round, the first loop, together with the interlocked shuttle-thread from the bobbin G, being carried up into ,the cloth.

The second loop is in like manner thrown oii from the shuttle, and drawn up and-interlocked with the shuttle-thread as a third loop is formed, the operation being repeated and continued until the required num ber ot' stitches have been made.

A most important point is the fact that the bobbin G is stationary, and does not revolve with the shuttle, being merely held against it by the plate t'. In' consequence of this arrangement, the shuttle-thread is not carried around and twisted, but is fed through the,holes t', in the same condition in which it is wound on the bobbin, the complicated devices for taking the twist out the under serrated surface of l the rear end of the machine, the presence of operatingof the shuttle-thread, which render machines of this class so objectionable, being entirely dispensed with.

Another plan of holding the bobbin up to the shuttle is illustrated in fig. 8. contained within a cup-shaped plate, t', which is held in its place by a light spriugrod, y, secured to the under side of the bed-plate, the pressure of which rod is, however, not sniicient to prevent the free passage of the loop of needle-thread between it and lthecup.

Although the thread which passes through the openings in the plate t' will generally prevent the latter from. turning, it may be rendered more secure by a finger, W, iig. l, extending from the base-plate A, and bearing against a projecting portion of the plate t', the

needle-thread passing between the tin ger and the plateA as it is carried round the shuttle.

On account of the adjustability of the hook e, its position in regard to the points of the shuttle may be regulated with the nicety required.

By operating the presser-foot and feedingaiog from devices over the workplate, where they interfere with movements of the operator, is avoided.

I claim as-my invention,iand desire to secure by Letters Patenty 1. A shuttle, F, having a hook, d, at the edge, and a book, e, at the back, and revolving' in an inclined shuttle-race, in combination with a bobbin, G, which lies within a perforated case, retained in a stationary position loosely within the shuttle, as described.

2. The hook c, bevelled at the edge, arranged at the back of the shuttle, so as to be adjustable ou the same, and operating substantially as specified.

3. A projection, f, arranged in respect to the shuttle, substantially as and for the purpose set forth.

4. The presserfoot, attached to an arm vibrating on a fulcrum at the rear. end of the machine, and operated by the Yneedle-arm, as described.

5. A feeding-foot, K, attached to an overhanging arm, pivoted at the rear end of the machine, and operated vertically and laterally'from the needle-arm by devices substantially as described, and for the purpose specified.

6. The arm I, hung to the base-plate A, and carrying the arm L and slide r, in combination with a wedge, q', which is forced between the slide and the arm L ou the movement of the needle-arm, substantially as and for the purpose specified.

In testimony whereof, I have signed my name to this specification, in the presence of' two subscribing witnesses.

Witnesses: THOS. LAMB.

JOHN WHITE, HARRY SMITH.

In this case the bobbiu is

Images