US1713943A - Sewing machine - Google Patents

Description

May 21, 1929. |3|NGHAM 1,713,943

SEWING MACHINE Filed Nov. '7, 1924 3 Sheets-Sheet 2 J. BINGHAM May Zl, 1929.

SEWING MACHINE Filed Nov, 7, 1924 5 Sheets-Sheet A EL patented May 2l, 1929.

UNITED STATES einen PATENT OFFICE.

JOSEPH BINGHAM, OF BELFAST, IRELAND, ASSIGNOR TO UNIVERSAL ART STITCH MACHINE LIMITED, OF BELFAST, IRELAND.

SEWING MACHINE.

Application led November 7, 1924, Serial No. 748,469, and .in Great Britain September 19, 1924.

The present invention relates to embroidery sewing machines of the class in which the machine head frame comprising the head proper, containing the needle bar and its mechanism, the horizontal arm, the support and a base together with the under shaft for operating the hook, all carried by the head frame, are so supported as to be capable of lateral movement about a pivotal support in order to give the needle an arcuate lateral movement to either side of a central position. In this class of machine the presser foot, feed mechanism and work plate are usually supported on a stationary base ilate. I The base plate of the machine head frame of the aforesaid class is usually disposed beneath the work plate and secured to a separate bracket comprising a tubular portion pivotally arranged on a stationary pillar, the front end (i, e. the end furthest away from the pivotal support) of the said base plate being thus overhung and unsupported with the result that as the machine head frame is built up of component parts and is unsupported at its overhanging end, it is liable to vibration when the machine is in operation, especially as the pivotal support wears.

It is one object of the present invention to overcome this vibration, another object of the invention being to improve the general construction and mechanism of the machine.

To the attainment of the aforesaid objects, according to this invention the machine head frame (which comprises the head proper, wherein the needle bar is disposed; the horizontal arm; the support and the head 'lrame base plate carrying the hook or shuttle operating mechanism) and the pivotal bearing are made integral so as to form a complete or unitary structure, which turns solidly about the pivotal support when giving the lateral throw to the needle and shuttle or hook.

The purpose of this arrangement is that the machine head frame is moved about its pivotal support as a complete or unitary structure, maintaining the parts associated therewith in the correct relative position; the complete machine (with the exception oi' the work plate which of course remains stationary) partaking of the lateral movement or swing.

The machine head frame is provided with means for assisting in preventing its vibration and also compensating for the eii'ect of wear on the pivotal support, forms o1' said means are hereafter described, for example, rollers carried at the front end, and at the under side, of the head frame base plate or spring action sliding feet working in an oil bath.

Improved mechanism is also provided for operating the hook and comprises a rod connecting the main shaft of the machine to a. counter-shaft, which is turnably mounted on a shaft arranged in the interior of the machine head irame and having a projecting arm connected to a link secured to the hook shaft.

Reference is now made to the annexed drawings, wherein is illustrated one example of a constructional embodiment of the present invention and whereon:-

Fig. 1 is a sectional elevation of the embroidery sewing machine;

Fig. 2 is anend view, partly in section, of the machine head frame, and also shows the link for laterally swinging the head frame.

Fig. 2a is an elevation and Fig. 2h a plan view of a. form of support for the front of the machine head frame.

Fig. 3 is a sectional plan view of the mechanism for operating the hook; and

Fig. 4 is a plan view of the base plate or table of the machine and shows the act-nat ing mechanism. l

Figs. 5 and 6 are respectively elevation and plan views off a form of cam and operating gear for the machine head frame.

Referring to the drawings The machine head frame l, comprising the head proper 2, the horizontal arm 3, the vertical support a, the head trame base plate 5 and the pivotal bearing 6, is, as will be clearly seen in Fig. l, made as a single hollow casting. The pivotal bearing 6 is bored out to form a bearing 7 which is turnably arranged on a stationary pivot 8 fixed to the machine base plate 9, the arrangement being such that the machine head frame can be swung about said pivot. The head trame is divided into two compartments l() and l1 by means of a transverse division wall 12, the

- compartment l1 being adapted to accommodate the needle bar 13 and its operating mechanism while the main shaft 14 is disposed in the interior of the compartment 10. The main shaft is journall'ed, at its rear end,

llO

v crank pin 2l. A plate 23 is secured to a member 22 and said member 22 is secured on'the main shaft -14 at the-end of the latter screwed into the main shaft.

which projects into the compartment 11, a crank pin. 24 being secured eccentrically to the plate 23 and one end of a connecting rod 33 is turnablyjmounted thereon and held against axial movement byineans of a screw 25 screwed into the end of said crank pin. Theother end of the connecting rod is turnably mounted on the projecting boss'26 of a member 2,6 whichl is slidably arranged on the needle bar and is adapted tol be secured Y inplace thereon by means of a fastening screw 27 screwed through the member 26 and bearing, at its inner end, on the needle bar, which latter is slidably arranged at its upperand lower ends, respectively, in bearings 28 and 29 formed in the head proper. A chain sprocket 30 is fixed at the other end of the main shaft 14 to a wheel 3l which is arranged on said shaft and prevented from rotating thereon by' means of a set screw 34, axial movement'jof said wheel being prevented by means ofafastening screw 32 A plate 34EL is secured at the front of the machine head frame and is apertured at 35 to allow the i needle to pass through said plate on` its downward stroke.

The motion of the main shaft 14 is communicated to a counter-shaft 36 by means of a connecting rod 37 turiiably mounted, at its upper end, on the crank pin 2l-and, at its lower end, on the tapered head of a screwed member 39 which is fixed to an arm or projection 38 of said counter-shaft by means of a nut 40. Said countershaft is .made in the form of a sleeve rotatably mounted on a shaft 41 supported in bearing blocks 42 and 43 provided at the under side of the head frame base plate 5. A projecting arm 44 is Y also formed on the counter-shaft 36 and a pin 45, screwed into a lever 46 fixed to the end of the hook shaft 47, is turnably arranged ina bearing 48 arranged to slide in the bifurcated end of the arm 44. Vrit the front end of the hook shaft 47 is mounted a hook carrier 49. `This hook carrier is suitably mounted to oscillate with the hook shaft but be capable of a limited amount of endwise movement thereon. The hook carrier 49 is located in its correct position on the hook shaft by the member 50 which is mounted on the hook shaft at the rear of the hook carrier 49 and which abuts against the rear end thereof, said member 50being provided witha sleeve portion which is slidablyand `rotatably mounted in the bearing of the shaft 72.

Vthe liooksliaft relatively to the needle. The

member serves virtually as adjustable stop `for axially locating the hook carrier on the hookshaftin its correct position relatively to the needle. It will be apparent, therefore, that the member is adapted for manual settinO and that in such setting it limits the movement of the hook shaft under the influence 'of ther-spring 53 (hereinafter refer-red to) to `thereby provide a: predeter'y mined `normal clearance between the hook i and needle.

In order to provide for automatic clearance of the hook by the needle irrespective of the thickness of the thread therein, the hook shaft' is slidably mounted in the bearing 5l at the front end and in the bearing 43 at the rear end and said shaft isV provided with a collar 471Vbetweenwhich'collar and the bearing 43 is located a spring. .The arrangement is such that the hook shaft can yield automatically inthe direction of its axis to give clearance-to the needle without interfering with the proper action of the hook. .The distance between thehook and i needle provides clearance for a thread of normal thickness, and in the :event of the use of a somewhat thicker thread, the hook is Y pushed away from the needle by the inter posed thread to prevent av thick thread from bending the needle. Y

The bearing block 51 is formed at its underside with a projecting boss 61 whereon the splitboss 62 of a two-armed bracket 63 rollers 64 serve to support the front end of the machine head frame base plate 5 and thus to prevent 4vibrations being set up in lOO carrying rotatable rollers 64 isrfixed.` The f placedv by Aspring feet 54l sliding Von a plate Y Y The machine is driven, from any suitable source, by means of a belt passing over-a driving pulley 65, Fig. 4, secured to a shaft- 66 jou-rnalled 'in bearings 67 and 68 which are fixed to the machinebase plate 9. A bevel wheel 70 is secured to the shaft 66 and gears with a bevelV wheel'7l'fixed to shaft 72 rrotatably arranged in bearings 73 and 74 provided on the base plate`9, the axis of said shaft being in the saine vertical plane as that of a shaft 75 but-arranged below that TheV shaft 75 is Arotatably mounted in bearings 76 and 77 and is connectedto the shaft 72 by means of liiiks78 and 79 connected to .the shafts 72 and 75, respectively, the arrangement being such that thespeed-of theshaft 75 is varied during each revolution to allow Athe machine head frame 1 to pivot from one side to the other of its central position While the needle is in its highest position. A chain sprocket 80 is secured to the shaft 7 5 and is connected to the sprocket 30 on the main shaft 14 by means of a chain, not shown. A handwheel 81, which also serves as a balance wheel, is secured to the shaft 72,

A crossover cam 82 is fixed on the shaft 66 and is engaged by a follower (not shown) provided on the under side of a grooved segmental guide member 88 which is pivotally arranged beneath a work plate 84, which is stationary being iixed in the usual way upon pillar like supports upon the machine base plate 9. A bearing block 85 engages in the groove in the segmental guide member 83 and one end of a connecting link 86 is pivoted thereto, the other end of the link being pivoted to a plate 87 fixed at the under side of the head frame base plate 5. A link 88 is pivotally connected, at one end, to the link 86 and, at its other end, to a link 89 which is fixed to a movable pillar 90 connected, beneath the .machine base plate 9, to the knee-lift lever mechanism (not shown). Any other suitable cam, or other means, may be employed in place of the cross-Over cam 82, for example, an alterna tive cam and gear are illustrated at Figs. 5 and 6 wherein the shaft 66 is provided with a bevel pinion 120 which gears with another bevel pinion 121 mounted on the end of a spindle 122 carried in bearings 123 in the base plate 9, said spindle having a cam 12A at its upper end which engages with a follower 125 secured upon the segmental guide member 83.

The feed mechanism for carrying the cloth through the machine is operated from a cam 91 on the shaft 72.

The presser foot comprises two slidably supported members 96 and 96" connected by a member 96c pivotally connected with an adjustable end 97 on the front end of a curved extension arm 98, the rear end of the arm being divided into two branches (Figs. 2 and 4) each branch having al laterally extending pin which is rotatably mounted in a bearing formed in one of the supports 100 located on the machine base 9 at either side of the standard l. The member 98 is adapted to be turned to raise and lower the pressure foot by means of a hand lever 56, a compression spring (not shown) being also provided for holding the presser foot in contact with the work plate 84 in its normal position. The presser feet 96a and 96b automatically accommodate themselves to the nature of the cloth under them and maintain an even pressure thereon irrespective of any differentiation in thickness of material below the two feet.

A grooved wheel 104 is secured to the driving shaft 66 of the machine and a friction Wheel 105, which is secured to a spindle 106 rotatably mounted in a bracket 107, is adapted to engage the groove in said wheel and is thus rotated thereby. The friction wheel 105 is so supported that it can be moved out of contact with the wheel 104. rlhe outer end of the spindle 106 is split at 108 and is Vadapted to retain thereon an empty bobbin 109 which, when rotated with the spindle 106 and friction wheel 105, lilled from another bobbin 110 rotatably supported on a bracket 111. The bobbin lilling device is enclosed by a cover plate 112.

Having now fully described my invention what l claim and desire to secure by Letters Patent is 1. A sewing machine including a single unitary khead frame structure, a needle bar carried by the structure, a needle bar operating mechanism carried by the structure, a hook shaft having a hook, means for oscillating the shaft, and means for normally maintaining the shaft in a position to provide a predetermined clearance between the hook and needle, said means permitting movement of the shaft by the thickness of the thread when interposed between the needle and hook to compensate for said thread thickness, said means causing the hook shaft to automatically return to normal posit-ion in the absence of thread bctween the needle and hook.

2. A sewing machine including a single unitary head frame structure, a needle bar carried by the structure, a needle bar operating mechanism carried by the structure, a hook shaft having a hook, means for oscillating the shaft, a spring for normally moving the hook shaft toward the needle, and means adapted for manual setting to limit movement of the hook shaft under said spring means, to thereby provide a prcdetermined normal clearance between the hook and needle, said spring means permitting movement of the hook shaft and hook in a direction from the needle to compensate for the thickness of thread `when interposed between the needle and hook.

In testimony whereof l affix my signature.

JOSEPH BINGHAM.

Images