US2012606A - Sewing machine feed mechanism - Google Patents

Description

Aug. 27, 1935. R. K. HOHMANN SEWING MAbHINE FEED MECHANISM Filed Jan. 25, 1931 2 Sheets-Sheet 1 A TTORNEY Aug 27, W35. R. K. HOHMANN SEWING MACHINE FEED MECHANISM Filed Jan. 25, 1931 2 Sheets-Sheet 2 IN V EN TOR. i/cbw/m ff flaHMkN/V ATTORNEY 'IIIM'IIIIIIIIl' Patented Aug. 27, 1935 Richard K. Hohmann, Brooklyn, N. Y., assignor,

by mesne assignments, to The Singer Manufacturing Company, Elizabethport, N. J., a corporation of New Jersey Application January 23, 1931, Serial No. 510,645

Claims. (01. 112-215) My present invention consists of certain im- I provements in sewing machine feed mechanisms and particularly in feed mechanisms for lock" stitch rotary hook sewing machines.

The general object of my invention is the provision of an improved sewing machine actuating mechanism and feed mechanism which is characterized by its freedom from vibration simplicity, compactness and durability, by its provisions facilitating its accurate assembly and incorporation in the machine, and by its capacity for regulation in accordance with the character of the material being sewn. A further object of my invention is to provide a simplified and improved coordinated arrangement of a feed-dog actuating mechanism and a rotary hook lockstitch-forming mechanism. A further and more specific object of my invention is the provision of mechanism for regulating the length of the stroke of the feed dog or point, ,and thereby the number of stitches'made' per inch of material. Other specific objects are the provision of an improved mounting of the feed dog on the feed bar, permitting any necessary or desirable adjustments'in the position of the work engaging surface of the feed dog to be efiected and other means for varying the plane of movement of the work engaging surface during the feed stroke of,

the dog.

The various features of novelty which characterize my inventionare pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, however, and the advantages possessed by it reference should be had to the accompanying drawings and descriptive matter in which I have illustrated and described preferred embodiments of the invention.

Of the drawings:

Fig. 1 is an elevation of a portable two thread rotary hook lock stitch motor driven sewing machine incorporating my invention, certain parts of the frame casting of the machine being broken away to illustrate parts enclosed thereby;

Fig. 2 is a planview of the machine illustrated in Fig. "1, partly in section on the line 2-2 .of

on the line vention illustrated in the drawings, A designates a base member upon which the frame casting of the machine is detachably secured. The latter comprises a bed B, a standard B, and a bracketarm 25 supported by the standard and terminating at its free end in a head B all of which except for the bed B are of well known construction. The bed B is in the form of a shallow inverted pan open at its underside with the edge.

of its rim portion seated on the base member A and preferably detachably secured to the latter. The top surface of the bed serves as the cloth plate or work support of the machine.

In the machine illustrated, the operating mechanism comprises a hook actuating shaft C carrying a rotary hook C at one end and journalled adjacent the latter in a partition B of the bed casting. The opposite end of the hook shaft is operatively connected to an electric motor M arranged in the bed by means of pulleys M and C mounted on the motor shaft M and hook shaft 0, respectively, and connected by an elastic of the hook shaft. The rotation of the needle shaft D effects reciprqcatory movements of a needle bar D and needle D and oscillating movements of a take-up lever D through suit able mechanism. A presser foot bar D presser foot D and other parts of conventional form are also illustrated.

Mounted within the hollow bed B is a short feed shaft E preferably arranged parallel to the hook shaft C and journalled in the partition 3* and in a spaced lug portion Bf depending from the under surface of the bed. The feed shaft E is driven at half the angular speed of the shaft C by means of meshing spur gears E and C carried by the shafts E and C, respectively. At one side of the partition 3*, the shaft -E carries a lift eccentric E and a feed eccentric E the functions of which will appear hereinafter. The work surface of the bed is provided with a suitable opening, the marginal portions of which form a seat B for a needle plate F removably mounted therein and level with the surrounding surface of the bed. The needle plate is formed with the usual opening F for a feed dog P, which opening is elongated in the direction of the feed to permit reciprocating movements relative thereto by the feed dog P.

The feed dog P is formed with a thin rearwardly extending and depending base portion P, which is adjustably mounted on a feed bar Q. The feed bar is formed with a slot or guideway Q in its rear end and arranged to receive a fulcrum stud Q mounted in the partitionB. With this construction the feed bar is capable of both oscillating and sliding movements relative tothe fulcrum stud. As indicated in Fig. 3, the rear portion of the body of the feed bar is provided with a recess Q opening to the slotted end of the bar and in which a spring Q is arranged, whereby the feed bar is constantly urged toward the front of the machine.

The operating mechanism through which the feed dog is moved through its desired path comprises novel-provisions operatively connecting the feed bar Q to the eccentrics E and E mounted on the feed shaft. These provisions include an intermediary member or thrust bar R which has one end pivoted on a pin R carried bya depending bracket R of the feed bar adjacent its rear end. The front end of the thrust bar engages the concavely curved rear surface of a vibratory operating lever S which is pivotally mounted on a post or stud S secured to the partition 13 and is interposed between the forward end of the thrust bar R and the eccentric E Any rotation of the feed shaft therefore efiects intermittent reciprocating movements of the feed bar and feed dog.

In the construction shown, the lift eccentric E acts on the underside of the feed bar adjacent its forward end to effect an intermittent raising and lowering of the feed dog relative to the needle plate. To somewhat reduce the amount of machining and wear on the feed bar while providing a good bearing surface for the lift eccentric and for other purposes, I have provided a narrow strip Q of steel or analogous material at the underside of the feed bar for the desired bearing surface. The bearing part Q is preferably arranged in a curved cut-away portion of the feed bar and held therein in resilient contact therewith by a screw Q adjacent its rear end.

The length of the feed stroke of the feed dog can be adjusted by, varying the pointof contact of the front end of the interponent R with.

the operating lever S. This adjustment is effected by a stitch regulating lever R which is fulcrumed on a stud R mounted in the partition B below and between the axes of the feed and hook shafts. The rear end of the stitch regulating lever is provided with a pin R received in a slot R formed in the thrust bar R adjacent its front end. The forward end of the lever l t projects through a vertical slot B formed in the front side of the bed, as shown in Figs. 1, 2, 3, and 6. The projection of the lever is suffiicent to enable it to be moved about its. fulcrum by the operator into various positions relative to the'slot. With the arrangement shown, when the lever B is moved into the lower portion of the slot, the feed stroke will be lengthened, while when the lever is moved towards the upper end of the slot, the length of the feed stroke will be decreased.

The lever R is advantageously bent laterally tially prevent accidental dislodgment of the lever from its adjusted position by contact with the clothing of the operator. Scale marks R indicating the number of stitches per inch for corresponding positions of the lever R in the slot, are marked on the bed alongside the slot, or preferably on an escutcheon plate R, which is arranged to register with the slot at its forward end and thus is in the view of the operator.

To provide a more secure positioning of the lever R the resiliently contacting portion of the lever may be formed with a rib R which is arranged to fit into any one of a series of ribreceiving notches R formed in the slotted portion of the escutcheon or bed or in both, as shown in Fig. 6. This arrangement effectively prevents dislodgment of the lever under small forces,

chiefly accidental, but the number of positions to which adjustments may be made is necessarily less than when the previously described arrangement is used.

The mechanism described for regulating the length of the feed stroke, and thereby the number of stitches made per inch of material, provides a sufficient number of feed adjustments for ordinary uses, permitting a desirable regulation of the stitching operation on fabrics of different weights or thicknesses as well as satisfying the ideas of different operators as to the proper number of stitches to be made per inch. In general, it is desirable to use a greater number of stitches per inch on relatively thin fabrics than with materials of greater weight or thickness.

In the assembly of the machine, the feed dog P is mounted along the outer fore portion of the feed bar .Q and is connected thereto by a fulcrum screw P, which extends through a suitable opening at the forward end of the feed dog base P into a corresponding threaded hole in the feed bar. A limited levelling adjustment of the feed dog about its fulcrum is possible by a special connection between the rear end of the feed dog base and the bar. These connecting provisions consist of a slightly enlarged opening P in the base P and through which a stud bolt P extends to engage a threaded recess in the feed bar. The enlargement of the opening P permits a slight angular movement of the feed dog about its fulcrum, which is normally sufficient to pennit any desiredadjustment of the feed dog for varying conditions of operation or to compensate for inaccuracies in the manufacture of the parts. In the ordinary use of the machine, the toothed surface of the feed dog extends above the upper surface of the needle plate only when the feed dog is making its feed stroke. Usually the levelling adjustment described is made by a mechanic during the assembly operations. Because of the usual permanent nature of this adjustment, the stud P is preferably made with an hexagonal head, as shown in Fig. 3, to permit a more secure connection.

The eifect of the above mentioned levelling adjustments of the feed dog is to vary the inclination of the toothed surface. or work engaging face of the dog relative to the needle plate. For ordinary operation a zero inclination or parallelism of said face and needle plate is most desirable. However, for relatively thin and delicate fabrics this surface may be arranged with a slight inclination toward its rear or heel. Such an arrangement provides a slightly tighter grip between the heel of the feed dog and the heel of the presser foot than with these parts in parallel and prevents the gathering or puckering of the material which would occur if the forward end of the feed point were tilted.

Provisions are also made for adjusting the actual height or elevation relative to the needle plate of the work engaging face of the feed dog during the feeding strokes of the feed dog. Such provisions are useful during the assembly of the machine and after it has been put .in operation. Inasmuch as the elevation of the feed dog during its feed stroke depends upon the relative proportioning of the feed device and lift eccentric, I provide simple and efiective means for varying the effect of the eccentric movement. In this embodiment, this result is accomplished by varying the position of the spring strip Q relative to the adjacent surface of the feed dog by means of a stud bolt Q arranged in a threaded passage in the feed bar at or adjacent the point of contact of the bearing strip with the eccentric. When the strip is pressed closely against the under surface of the feed bar, the elevation of the feed dog will be at its lowest. When, however, the stud is rotated to move the bearing strip away from the under surface of the feed bar, the elevation will be increased by an extent corresponding substantially to the change in position of the bearing strip relative to the feed dog. This adjustment of the elevation of the feed dog movement may be quite necemary or desirable in the assembly of the machine or to permit a higher grade of work on more delicate fabrics. Such adjustment of elevation of the working engaging face of the feed dog is necessary also to compensate for the effect on the elevation of said face of the previously described levelling adjustments since the spacing of the axis of the fulcrum screw P to one side of the work engaging face of the feed dog results in a variation in the elevation of said face whenever a levelling adjustment is made.

The feed bar Q is also provided with a tongue Q at the inner side of its forward edge, one side of which is in the same vertical plane as thecorresponding side of the slotted feed bar section Q. These surfaces are arranged in sliding contact with the outer side of the. partition 3*, providing additional guiding of the feed bar durin its movements.

Reference may be had to Patent No. 1,916,860, dated July 4, 1933, on my prior application Serial No. 242,368, filed Dec. 24, 1927, which discloses but does not claim certain novel features of construction disclosed and claimed herein and of which this application is a division.

By providing a sewing machine with three interconnected parallel rotary shafts terminating adjacent the closely juxtaposed parallel planes of action of the stitch-forming and feeding instrumentalities driven by said shafts, I am enabled' to secure many important advantages ciprocating and oscillating parts are materially reduced. I

The feed-lift eccentric may be located atjthe end of the feed-shaft which is preferably disposed closely in rear of the hook-shaft and, be-

ing close to the line of feed, the feed-lift action of said eccentric upon the feed-bar may be applied desirably close to the front end of the feedbar and to the vertical plane thereof without encroachment upon the field of action of the rotary hook. These considerations'minimize tilting or torsional strains in the feed-bar, reduce the reactionary strains on the pivotal bearing at the end of the feed-bar and enable the feed-bar to be made correspondingly light in weight without sacrifice of the necessary strength.

The rotary hook, which is preferably closely nested in front of the feed-lift eccentric, and below the forwardly overhanging feed-dog car ried preferably at the front end of the feed-bar, is entirely exposed both in front of and below its peripheral rim portion and in front of its face. It is thus well exposed for inspection, cleaning, timing, removal and replacement of the bobbin. The feed-bar may be made desirably long and located preferably entirely in rear of the rotary hock without positioning the latter abnormally close to the front edge of the conventional sewing machine cloth-plate.

A rotary hook of conventional size may be mounted directly upon the end of the faster of the two shafts in closely nested relation with, but without encroachment upon the feeding mechanism and the combined feeding and rotary hook mechanism may be housed 1n a sewing machine of commercially normal depth.

While in accordance with the provisions of the statutes, I have illustrated and described the best form of embodiment of my invention now known to me, it will be apparent to those skilled in the art that changes may be made in the form of the apparatus disclosed without departing from the spirit of my inventionas set forth in the appended claims and that in some cases certain features of my invention may be used to advantage without a corresponding use of other features.

Having now described my invention what I claim as new and desire to secure by Letters Patent, is: l

1. In a sewing machine, the combination with a bed, of a feed shaft journalled in said bed, a feed dog, a feed bar arranged for reciprocating movements relative to said bed and carrying said feed dog, an arcuate lever adjacent said feed bar, a link carried by said feed bar and having its free end abutting one side of said lever, an eccentric on said feed shaft and arranged to operatively engage the opposite side of said lever to oscillate the same about its fulcrum, and means for varying the point of abutment of said link with said lever.

2. In a sewing machine, the combination with a bed, of a feed shaft journalled in said bed, a feed dog, a feed bar arranged for reciprocating movements relative to said bed and carrying said feed dog, an arcuate lever adjacent said feed bar, a link carried at one end by said feed bar and having its opposite end abutting one side-of said lever, an eccentric on said feed shaft and arranged to operatively engage the opposite side of said lever to oscillate the same about its fulcrum, and a lever engaging said link and arranged to vary. the point of abutment of said link with said arcuate lever.

3. In a sewing machine, the combination with a bed and needle plate, of a feed dog having a work engaging face and means for giving feeding movements to said dog, said means comprising a feed bar mounted in said bed for reciprocating and oscillating movements,-'a connection between said dog and bar including means for adjusting the position of the dog relative to the bar angularly about an axis which is transverse to the plane of said feeding movements and which is displaced horizontally from said work engaging face to thereby vary the inclination of said face to said plate during said feeding movements, and separate adjusting means for varying the elevation of said face relative to said plate during said feeding movements.

4. In a sewing machine, the combination with a bed and needle plate, of a feed dog having a work engaging face and means for giving feeding movements to said dog, said means comprising a feed bar mounted in said bed for reciprocating and oscillating movements, a connection between said dog and bar including means for adjusting the position of the dog relative to the bar angularly about an axis which is transverse to the plane of said feeding movements and which is displaced horizontally from said work engaging face to thereby vary the inclination of said face to said plate during said feeding movements, and

means for adjusting the position of said feed barrelative to said bed to thereby vary the elevation of said face relative to said plate during said feeding movements.

5. In a sewing machine, the combination with a bed and needle plate, of a feed dog having a work engaging face, and means for giving feeding movements to said dog, said means comprising a feed bar mounted in said bed for reciprocating and oscillating movements, a pivotal connection between said dog and bar, the axis of said connection being parallel to said plate and transverse to the direction or" said feeding movements and spaced away from said face, whereby adjustment of said dog relative to said bar about said axis varies both the inclination and elevation of said face relative to said plate during said feeding movements, locking means for securing said dog to said bar in different adjustment positions of said dog about said axis relative to said bar and means for adjusting the position of said feed bar relative to said bed to thereby vary the, elevation of said face relative to said plate during said feeding movements.

6. A lock-stitch sewing machine having a frame including a bed, a cloth-plate, a standard rising from said bed and a bracket-arm carried by said standard and overhanging said bed, an upper rotary shaft journaled in said bracket-arm, twolower rotary shafts journaled below said clothplate in parallelism with each other and with the cloth-plate, means interconnecting said three shafts to cause them to rotate in timed relation and each with a uniform angular. velocity, a reciprocatory needle connected to be actuated by said upper rotary shaft, a rotary hook cooperating with said needle below said cloth-plate and actuated by one of said lower rotary shafts, a feedbar, a feed-dog carried thereby and mechanism actuated by the other of said lower rotary shafts for imparting four-motion movements to said feed-dog, said mechanism comprising a feedlift eccentric fixed to the free end of said shaft for imparting a rising and falling movement to one end of said feed-bar, a second eccentric fixed to said shaft, oscillatory mechanism actuated by said second eccentric and acting upon the other end of the feed-bar for imparting a feeding movement to said feed-bar, and means accessible at the front of the machine for adjusting said oscillatory mechanism for varying the forward feeding movement of said feed-dog.

-7. A sewing machine having a frame including a bed, a cloth-plate, a standard rising from said bed and a bracket-arm carried by said standard and overhanging said bed, an upper rotary shaft journaled in said bracket-arm, a rotary shaft located below said bed, a rotary lock-stitch looptaker carried by said shaft, a rotary feed-shaft located below said bed and arranged in parallelism with the other two shafts, means interconnecting said three shafts to cause them to rotate in timed relation and each with a uniform angular velocity, a reciprocatory needle connected to be actuated by said upper rotary shaft, a feed-bar located entirely at one side of said loop-taker and in a plane substantially 'at right angles to its axis of rotation, a feed-dog carried thereby, a feed-lift eccentric fixed to one end of said rotary feedshaft'for imparting a rising and falling movement to one end of said feed-bar, a second eccentric fixed to said feed-shaft, and means interposed between said second eccentric and the other endof the feed-bar for imparting a forward feeding movement to said feed-dog.

8. A sewing machine having a frame including a bed, a. cloth-plate, a standard rising from said bed and a bracket-arm carried by said standard and overhanging said bed, an upper rotary shaft journaled in said bracket-arm, a rotary shaft located below said bed, a rotary lock-stitch looptaker carried by said shaft, a rotary feed-shaft located below said bed and arranged in parallelism with the other two shafts, means interconnecting said three shafts to cause them to rotate in timed relation and with a uniform angular velocity, a reciprocatory needle connected to be actuated by said upper rotary shaft, a feed-bar located entirely at one side of said loop-taker and in a plane substantially at right angles to its axis of rotation, a feed-dog carried thereby, a feed-lift eccentric fixed to one end of said rotary feed-shaft for imparting a rising and falling movement to one end of said feed-bar,'a second eccentric fixed to said feed-shaft, means operatively connecting said second eccentric with the other end of the feedbar for imparting a forward feeding movement to said feed-dog, and means operable from the vside of the loop-taker opposite to the feed-bar for varying the forward feeding movement of said feed-dog.

9. A sewing machine having a frame including a cloth-plate and a bracket-arm overhanging said cloth-plate, a rotary needle-reciprocating shaft,

journaled in said bracket-arm, a rotary looptaker actuating shaft and a rotary feed-actuating shaft journaled beneath said cloth-plate and arranged in parallelism with the needle-reciprocating shaft, driving connections between said shafts whereby the feed-shaft and the needle-reciprocating shaft are caused to rotate at the same angular velocity and the loop-taker actuating shaft at twice the angular velocity of the other two shafts, a feed-bar, a feed-lift element carried by said feed-shaft, a feed-advance actuating element fixed to said feed-shaft, and operative connections between said feed-advance element and said feed-bar to impart work-advancing movement to the feed-dog, including means manually operable during the operation of the machine for varying the amplitude of feed.

10. A sewing machine having a frame including a cloth-plate and a bracket-arm overhanging said cloth-plate, a rotary needle-reciprocating shaft journaled in said bracket-arm, a rotary looptaker actuating shaft and a rotary feed-actuating shaft journaled beneath said cloth -plate and arranged in parallelism with the needle-reciprocating shaft, driving connections between said shafts whereby the feed-actuating shaft and the needlereciprocating shaft arecaused to rotate at the same angular velocity and. the loop-taker actuating shaft at twice the angular velocity of the feed-bar for imparting work-advancing movements to said feed-dog, and manually operable means for varying the effective action of said vibratory member to impart work-advancing movement to said feed-dog.

11. A sewing machine having a frame including I cloth-plate, a rotary needle-reciprocating shaft.

j ournaled in said bracket-arm, a rotary loop-taker actuating shaft and a rotary feed-actuating shaft journaled beneath said cloth-plate arranged in parallelism with the needle-reciprocating shaft, driving connections between said shafts whereby the feed-shaft and the needle-reciprocating shaft are caused to rotate at the same angular velocity and the loop-taker actuating shaft at twice the angular velocity of the other two shafts, a feeddog, a feed-bar, a feed-lift element carried by said feed-shaft, afeed-advance element fixed to said feed-shaft, a constant throw member operatively engaged by said feed-advance element and deriving therefrom constant operative movement, and means for transmitting work-advancing movement to the feed-bar from said constant throws member including a pivotally supported intermediary member and manually operable means for shifting I said intermediary member about its pivotal axis to thereby vary the effective action of said constant throw member thereupon. I

12. A sewing machine having a frame including a cloth-plate and a bracket-arm overhanging said cloth-plate, a rotary needle-reciprocating shaft journaled in said bracket-arm, a rotary loop-taker actuating shaft and a rotary feed-actuating shaft journaled beneath said cloth-plate and arranged in parallelism with the needle-reciprocating shaft, driving connections between said shafts whereby the feed-shaft and the needle-reciprocating shaft are caused to rotate at the same angular velocity and the loop-taker actuating shaft at twice the angular velocity of the other two shafts, a feed-dog, a feed-bar carrying said feed-dog mounted for rocking and bodily endwise movements, a feed-lift element carried by said feed-shaft for rocking said feedbar to thereby transmit rising andfalling move- 13. A sewing machine having a frame, including a cloth-plate and a bracket-arm overhanging said cloth-plate, a rotary needle-reciprocating shaft journaled in said bracket-arm, a. rotary loop-taker actuating shaft and a rotary feed-actuating shaft journaled beneath said cloth-plate and arranged in parallelism with the needle-reciprocating shaft, driving connections between said shafts whereby the feed-shaft and the neesame angular velocity and the loop-taker actuating shaft at twice the angular velocity of the other two shafts, a feed-dog, a feed-bar carrying said feed-dog mounted for rocking and bodily endwise movements and. located entirely at one side of said loop-taker actuating shaft and in a plane substantially at right angles to its axis of rotation, a feed-lift element carried by said feed-shaft and arranged to impart rising and falling movements to said feed-dog, a feed-ad- Vance element carried by said feed-shaft, a member deriving constant movements from said feedadvance element, an interponent operatively engaged by said member to impart endwise movements to said feed-bar, said interponent being mounted for shifting movement relative to 'said feed-bar abouta pivotal axis partaking of the bodily endwisamovements of the feed-bar, and manual means for shifting said interponent about its pivotal axis to thereby vary the amplitude of if:hedwgrk-advancing movements imparted to said ee ar.

14. A sewing machine having, in combination,

a bed, an overhanging bracket-arm, a rotary hook shaft journaled in said bed, a rotary hook fixed to one end of said shaft, a rotary feedshaft journaled in said bed at one side of the dlereciprocating shaft are caused to rotate in the Y hook-shaft and having one of its ends terminating adjacent said hook, a rotary needle-bar shaft journaled in said bracket-arm, means connecting said shafts whereby the feed-shaft and needle-bar shaft are caused to rotate at the same speed and the hook shaft at twice the speed of the other two shafts, a feed-bar, a feed-dog carried thereby and overhanging saidhook, and

eccentrics carried by said feed-shaft and opera tively associated with said feed-bar for imparting rising-and-falling and feed-and-return movements to said feed-dog.

15. In a sewing machine, in combination, a frame having a power-receiving end and a sewing end and comprising a bed, a standard rising from said bed at the power receiving end of said frame, a bracket-arm carried by said standard and overhanging said bed and terminating at its free end in a head at the sewing end ofsaid frame, stitch-forming instrumentalities including a reciprocatory needle and a horizontal axis rotary hook, a needle-bar carrying said needle and mounted in said bracket-arm head, a feeddog, a four-motion feed-bar carrying said feeddog, said needle, rotary hook and feed-bar being arranged to work in parallel vertical planes which are in closejuxtapositionat the sewing end of the machine frame and are transverse to the direction of length of said bed and bracket-arm,

andthree parallel rotary shafts for driving said I stitch-forming and feeding instrumentalities, said shafts being normal to and terminating adjacent the juxtaposed parallel planes of action .of the stitch-forming and feeding instrumentalitles .at the sewing end of the machine frame, one of said shafts being an upper shaft which is journaled in said bracket-arm and connected at the free end of the latter to reciprocate said needlebar, the remaining two shafts being lower shafts and journaled in said bed, said rotary hook being mounted on one of said lower shafts, feed-lift and feed-advance eccentrics mounted on the other of said lower shafts and connections adjacent the sewing end of the machine frame for imparting to said feed-bar its operative movements, and means interconnecting said three shafts in timed relation to cause the needle-bar shaft and feedshaft to run at the same speed and the hook shaft to make a plurality of rotations to one rotation of the needle-bar and feed-shafts, one of said shafts having power-receiving means thereon at the power-receiving end of the machine frame.

16. A sewing machine having, in combination, a bed, an overhanging bracket-arm, a rotary needle-bar shaft journaled in said bracket-arm, a rotary hook-shaft journaled in said bed, a feedshaft journaled in said bed and located in rear of and in substantially the same horizontal plane as the rotary hook-shaft, means interconnecting said three shafts for causing said needle-bar shaft and said feed-shaft to rotate at the same speed and the hook-shaft to make aplurality of complete rotations for each rotation of the other two shafts, a rotary hook secured to said hook shaft, 2. pair of eccentrics on said feed-shaft, a feed-bar, a feed-dog carried thereby, and mechanism actuated by said eccentrics for imparting a feed and-return and rising-and-falling movement to said feed-bar.

17. A sewing machine having, in combination, a bed and an overhanging bracket-arm, a needlebar shaft journaled in said bracket-arm, a hook shaft and a feed-shaft journaled in said bed, said needle-bar shaft and said hook-shaft being arranged in substantially the same vertical plane and the feed-shaft being disposed in rear of and in substantially the same horizontal plane as the hook shaft, means interconnecting said shafts for causing them to rotate in timed relation, the needle-bar shaft and feed-shaft rotating at the same speed and the hook shaft making a plurality of complete rotations for each rotation of the other shafts, a rotary hook carried by said hook shaft,

, a feed-lif t eccentric carried by said feed-shaft and shaft journaled in said bed, a rotary lock-stitch hook fixed to one end of said shaft, a rotary feedshaft Journaled in said bed and having one of its ends terminating adjacent said hook, a rotary needle-bar shaft journaled in said bracket-arm, gearing connecting said shafts whereby the feedshaft and needle-bar shaft are caused to rotate at the same speed and the hook shaft at twice the speed of the other two shafts, a feed-bar located mainly in rear of said hook-shaft, a feed-dog carried thereby an'd overhanging said hook, and a. pair of feed eccentrics carried by said feed-shaft, one of said eccentrics imparting a rising-andfalling movement to said feed-bar and the other of said eccentrics imparting a backward and forward'movement to said feed-bar.

19. A sewing machine having, in combination, a bed and overhanging bracket-arm, a feed-shaft journaled in said bed, a hook shaft journaled in said bed in advance of said feed-shaft, said shafts being parallel and located in substantially the same horizontal plane, means for actuating one of said shafts, gearing connecting said shafts whereby the hook-shaft performs a plurality of complete rotations for each complete rotation of the feedshaft, a rotary hook carried by said hook shaft and operating in a vertical plane, the radius of the hook being less than the distance between said shafts, a feed-bar disposed mainly in rear of said hook, a feed-dog carried thereby and overhanging said hook, and a pair of feed eccentrics fixed to said feed-shaft for actuating said feed-bar.

20. A sewing machine having in combination, a bed and overhanging'bracket-arm, a feed-shaft journaled in said bed, a hook shaft journaled in said bed in advance of said feed-shaft, said shafts being parallel and located in substantially the same horizontal plane, means for actuating one of said shafts, gearing connecting said shafts whereby the hook shaft performs a plurality of complete rotations for each complete rotation of the feed-shaft, a rotary hook carried by said hook shaft and operating in a vertical plane, the radius of the book being less than the distance between said shafts, a feed-bar disposed in rear of said hook and having one of its ends mounted for pivotal movement at a point remote from said hook and its other end located adjacent said hook, a feed-dog carried by said feed-bar and overhanging said hook, a feed-lift eccentric carried by said feed-shaft and located adjacent said hook, a second eccentric fixed to said feed-shaft, and mechanism interposed between said eccentric and the feed-bar for imparting a feed-advance movement thereto. v

RICHARD K. HOHIMANN.

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