US2054078A - Sewing machine - Google Patents

Description

Sept. 15, 1936. I. 3 3U|;DBOUR| l ET Al. 2,054,078

SEWING MACHINE Original Filed Sept. '7, 1953 3 Sheets-Sheet l Flgi Witness aw? fi/a/zzaj l zom, M/M

p 1936- J. GOULDBOURN ET AL 2,054,078

SEWING MACHINE Original Filed Sept. '7, 1.953 3 Sheets-Sheet 3 lrwentofii vided for adjusting Patented. Sept. 15, 1936 Joseph Gouldbourn,

Thomas Aubrey Kestell,

and Frank Bycroft Keall, Leicester, England, assignors to United Shoe Machinery corpora-'- tion, Paterson, N. J., a corporation of New Jersey Original application September 7, 1933, Serial Divided and thisv application March 23, 1935, Serial No'. 12,608. In Great Britain October 11, 1932 1 14 Claims.

This invention is concerned with improvements in or relating to sewing machines for operating upon thick stubborn materials such as leather.

An illustrative machine of this kind is disclosed in United States Patent No. 1,169,909 granted to Fred Ashworth, February 1, 1916, and also in the present inventors co-pending application Serial No. 688,480, filed September '7, 1933, for Sewing machines, of which application the present application is a division.

Usual machines of this kind employ mechanism for actuating the sewing instrumentalities which, while satisfactory for enabling the machine to sew efficiently up to a speed of five hundred stitches per minute is not suitable for enabling the machine to run at a relatively high speed, for example, to sew a thousand stitches per minute. Operation at such speeds not only imposes undesirable straining effects on the stitch-forming mechanisms of the machine, but the work holding and feeding members including the presser-foot may be prevented from operating properly due to the heavy forces required to insure reliable and uniform feed at that rate.

The objects of the present invention are to improve the action of the presser-foot in a high speed leather sewing machine and to ensure that the presser-foot in engaging the work will hold the work securely as fed and after releasing the work at the end of the seam may be brought against the work without impact in starting the machine again in operation.

In an illustrative embodiment of the invention, the presser-foot is actuated by a lever and is held locked against movement in either direction by a support on which the lever is fulcrumed, and a wedge and wedge-shaped member on the support are provided with cooperating means for locking them against movement with relation to each other and to the frame of the machine while the presser-foot grips the work.

When the machine is stopped, the presser-foot is raised automatically against the action of a spring and conveniently accessible means is prothe height to which the presser-foot is lifted so that in reengaging the work before starting a new seam there will be little or no impact on the work due to raising the presser-foot excessively above the work surface.

In connection with this feature of the invention there is provided a novel adjustable pulloff mechanism having suitable means for indicating the adjustment.

In order that the nature of the present invention may be more clearly understood the illustrative embodiment will now be described and the above objects of the invention and its several features will become apparent to those skilled in the art from said description.

In the drawings:

Figure 1 is a view from the right hand side of a machine embodying the invention and showing certain parts of the head of the machine; Figure 2 is a view from the right hand side of the machine showing mechanism for raising and lowering the presser foot of the machine, for locking the presser-foot against the work and for providing other motions to the operating parts; Figures 3 and 4 are detail views on an enlarged scale from the right hand side and front respectively showing an adjusting lever for varying the extent to which the presser-foot is lifted at the conclusion of a sewing operation; Figure 5 is a detail sectional plan view of parts associated with the presser-foot controlling and thread measuring mechanism; Figure 6 is a right hand side elevation showing certain details of the presser locking means; and Figure 7 is a view showing partly in section certain other details of the presser-foot locking means.

The said illustrative embodiment of the invention is a machine designed for sewing the outsoles of welted shoes totheir welts and comprises a column I and a head casting 5. A main shaft I0 is arranged parallel to the front of the machine (1. e. from left to right) and has mounted on it a main driving clutch arranged to be driven at high speeds. The shaft I0 has secured to it various cam members and gears which actuate needle and awl mechanisms of the machine, resser-foot lifting and locking, shuttle and other operating mechanisms.

The stitch forming devices include a curved hook needle l2, an awl M, a looper IS, a shuttle l8 and means for feeding the shoe step by step through the machine comprising a horizontally swinging work-supporting table 20 and a cooperating presser-foot 22 illustrated in Fig. 2. The

to it a link 82 which'is similarly connected to the forward-end of an arm 84 mounted on a shaft 88. The arm 34 is coupled to one arm of a bellcrank lever "mounted to rock about the shaft 88, which bell-crank lever is prevented from moving along the said shaft by the adjacent parts. Theother arm of bell-crank lever 88 is connected by a rod '48 to a link 42 (see also Figs. 6 and '7). The forward end of the link 42 is connected by a pin 44 with a stirrup 45 which is located in a guide way in a block 48 secured to the machine frame.

To position the presser-foot yieldingly against the work there 'is provided at the right side of the machine a horizontal spindle 48 (see Fig. 1) surrounded by a sleeve 88 within a bearing in the machine frame. j

The sleeve ill has formed in its left end, a short rearwardly and upwardly curved finger I2 and a split clamping collar 84 is mounted on the right end. The extreme right end of the spindle 48 has a pointer 58 (Fig. l) secured to it. The clamping collar has a short arm 58 depending fromit to the lower end of which the front end of a tension spring 88 is secured, which spring extends rearwardly to a fixed pin. The spring,

therefore, tends to rock the spindle 48 and sleeve 88 in a counter-clockwise direction looked at from the right hand side of the machine to lift the upwardly-curved finger I2 against the underside of the stirrup 48. The spring it! normally urges the finger 52 upwardly and tends to lift the stirrup 48 and therefore the forward end of link 42, thus tending to urge the preset foot towards the work table. I I

To lift the presser-foot-away from the work at the correct time the rear end of link 42 is connected bya rod 62 to an arm of a bell-crank leveroperated by a cam 88 on the shaft II. The

lower end of rod 82 is connected to the lever 84- by a bolt 88 which passes through a slot II in the bell crank lever, whereby the movement imparted tothe rod by the action of the cam may be varied.

The mechanism for urging the presser-foot yieldingly down on to the work is automatically locked in position each time when the presserfoot has been' urged against the work by the spring controlled fingeri! on the stirrup 48 in order to hold the presser-foot against movement upwardly as the result of upthrust on it due to upward pressure exerted on the work by the piercing action of the awl. For this purpose, in the illustrated form of the invention, the rear end of link 42 to which bell crank lever 84 is connected is heldin fixed position by the cam 68. To hold the forward end of link 42 there is loosely mounted upon pin 44 a pair of depending wedge plates 88, 82 (Fig. '7) located side by side, but spaced apart somewhat. I V

The outer faces of the two wedge plates are parallel and the wedge plates are located within the fixed guideway 48, the front and rear sides of the guideway bridging across the space between the wedge plates. The inner opposing faces of wedge plates 80, 82 are relatively inclined so that the space between them gradually diminishes toward their ends. The lower ends of the plates are turned towards each other and have a tongue and groove connection 84 with each other to maintain them in. relation. Also loosely carried by the pin 44 is a central .wedge member 88 which extends centrally of the space between wedge plates 88, 82 and member 88 is so tapered that its sides lie parallel with the inclined sides of the wedge plates. The diameter of the hearing in the central wedge member 88 is slightly the said pin) are urged downwardly against the upper surface of the said pin. A relatively fixed wedge member 86 and the-wedge plate 82' near the bottom of the latter and a series of steel rollers 82 o wedge p ates are supported on the bar 88 and arranged one above the other in the space between the plate and the member, the rollers being of such a diameter that no two rollers can lie directly one behind the other, but are caused to lie in a staggered relation so that alternate rollers engage respectively the central wedge member 88 and against the side of the wedge plate 82. The bar 80 is tapered on its upper face (as shown-in Fig. 6) andcan be adjusted to change the initial setting of the rolls. A presserfoot locking finger 94 passes rearwardly into the gap between the wedge plate 82 and the central wedge member 88 and lies over the topmost roller 82 and is mounted to rock about a pivot. and has an arm 88 pivoted to the upper end of a spring pressed plunger 88 mounted in the upper end of a rod I80, the lower end of which is connected to shell crank lever I 82 rocked, when the foot is to be locked against the work, by a cam on the mainshaft II. .The finger 84, in moving downwardly, presses the rollers which exert great side pressure against both the central wedge member 88 and the side wedge plate 82 with which they contact, thu's urging the latter against the side of its guideway and locking the central wedge member 86 to the wedge plate 82 against downward movement. The wedge member 88 is supported laterally by aspacing piece bar 88 projects into the gap between the central the same length as the width of the I84 arranged between the central wedge member 88'and the wedge plate 88. The locking effect of the device arises from the fact thatthe bearings for the pin 44 both in the central wedge member and also in: the wedge plates are larger in diameter than the pin and any tendency for down ward movement of the pin due to lifting the presser-foot causes a slight downward movement of the central wedge member 82 relatively to the wedge plates. Such movement is immediately resisted by the rollers. After a work feeding movement has finished and the presser-foot has been lifted, returned idly to its right and allowed this has occurred, the locking finger 84 is once more lowered to lock the presser-foot against the work.

Means is provided the machine for automatically lifting the presser-foot to a position in The said means operates by means of a rod I88 pressing the spring pressed plunger 88 to which the' forward arm 96 of the locking finger is connected and to lift and. maintain the presser-foot out of contact with the work. When the machine is to be restarted the presser-foot is again lowered and locked in work engaging position. The three-arm lever I08 (Fig. 2) is rotatably mounted on a shaft H0. Lever I08 has an upwardly extending arm H2 to which the rod I06 is connected. Rod I06 is connected at its end to an arm H4 (Fig. 1) secured to a shaft H6 at the rear of the machine, which is rocked whenever the machine stops. Lever I08 also has an arm H8 formed with a cam face I20 engaging aroll I22 on the spring-pressed plunger 88 to which arm 96 of the presser-foot locking finger 94 is connected. Lever I08 also has short arm I24 carrying a pin I26. An adjustable presser-foot lifting lever I28 is mounted upon an eccentric disc I30 (Fig. 3) formed on one end of shaft H and lever I28 lies close against lever I08. Lever I28 has a rearwardly extending nose I32 which overlies a.v lug I34 projecting from rod 40 and lever I28 also has a forwardly projecting arm I36 which lies above pin I26 on lever I08.

As the machine comes to rest, shaft H6 at the rear of the machine is rocked in a clockwise direction looked at from the right and thus causes lever I08 to rock about shaft H0. Aslever I08 is rocked the cam face I20 moves across and depresses the plunger 88, as shown in Fig. 2, thereby raising finger 94 and unlocking the wedge members 80, 82 of the presser-foot locking device. When this has occurred pin I26 on arm I24 raises arm I36 of lever I28 thereby lowering nose I32 and raising the presser-foot out of contact with the work. The eccentric disc I30 has an upwardly extending handle I38 (Figs. 3 and 4) secured to it by which the disc may be rotated to raise or lower lever I20 bodily so that the extent of the rocking movement imparted to it by pin I26 when the lever I08 is rocked may be varied to cause the presser-foot to be raised, as the machine stops, a greater or less amount in accordance with the thickness of the work, it being desirable that the lifting lever I28 be so adjusted when working on thin work that the presser-foot is not lifted an undue amount above the work. If the presser-foot were lifted a large amount above the work it would, when lowered on to the work next put into the machine, be caused to strike against the work with excessive force by the spring 60. Handle I38 on the eccentric disc I30 carries a spring pressed plunger I40 which moves over a sector I42 and serves, by engaging in one of a series of notches in the sector, to retain the handle in any position into which it may have been adjusted. Lever I08 has an upwardly extending handle I44 (shown in Fig. 1) secured to it which may be used to rock said lever in a direction to raise the presser-foot at any time to allow the work to be removed from the machine.

In connection with the presser-foot actuating mechanism there is provided a needle thread pull-off having an adjustable actuating mechanism. The thread passes from the supply upwardly through a locking device I46, and between a pair of guide rolls I48, I50. The thread is acted upon between the guide rolls by a pullofi roll I52 at the end of measuring lever I54 fulcrumed on a fixed shaft I56 and connected at its rearward end by a link I58 to the upper ends of a double link I60 (see Fig. the members of which are of the same length as link I58. The lower ends: of this double link are pivoted to a swinging bifurcated bracket I62, the limbs'of which are spaced apart to embrace the double link I 60. The said bracket has secured at its reaward end the horizontal spindle 48 extending to the right and a second spindle I64 to the left Y having a bearing in the machine frame. A rod I66 is secured to the pivotal connection between the links I58 and I60 and is connected to a bell crank lever I62 mounted on a rod I64 and provided with a roll which enters a cam groove in a cam secured to the shaft I0. The presser-foot actuating spring 60 tends to rock the bifurcated bracket I62 downwardly about spindles 48, I64 as the finger 52 follows the movements of the stirrup 45, the arrangement being such that the extent to which bracket I62 is moved is determined by the thickness of the work., The thinner, therefore, the work being operated upon, the less will be thevertical movement of thread measuring lever I54, and the thicker the work, the greater will be the lever movement. When the clamping collar 54 is loosened from clamping engagement on the spindle 48 the spindle may be rotated relatively to the sleeve 50 to adjust manually the action of the pull-off, the pointer 56 cooperating with marks on arm 58 for indicating the relative adjustment.

The nature and scope of the invention having been indicated, and a construction embodying the several features of the invention having been specifically described, what is claimed is:

1. A lockstitch outsole shoe sewing machine having, in combination, stitch forming devices, a work support, a presser-foot, mechanism for actuating the presser-foot comprising a pivoted lever, connections between the lever and the presserfoot acting when the lever is moved in opposite directions to raise and lower the presser-foot, a. movable support on which the lever is fulcrumed, a spring acting to force the presser-foot yieldingly against the work when the support is unlocked, and means for locking the support against movement in either direction comprising a locking wedge mounted on said support for slight longi tudinal movement with relation thereto, a cooperrating wedge shaped member mounted on said support for slight longitudinal movement with relation to said support and to said locking wedge,

a guideway in which said locking wedge and wedge shaped member are mounted, and means for locking said wedgeand wedge shaped member from movement with relation to each other and to said guideway.

2. A lockstitch outsole shoe sewing machine having, in combination, stitch forming devices, a work support, a presser-foot mechanism for actuating the presser-foot comprising a pivoted lever, connections between the lever and the presserfoot acting when the lever is moved in opposite directions to raise and lower the presser-foot, a movable support on which the lever is fulcrumed, a spring acting to force the presser-foot yieldingly against the work when the supportis unlocked, and means for locking the support against movement in either direction comprising two wedge plates mounted on said support for slight longitudinal movement with relation thereto and having outer parallel surfaces and inner surfaces inclined towards each other from one end to the other, a guideway for said plates, a central wedge member mounted on said support for slight longitudinal movement with relation thereto provided with surfaces parallel to the inclined surfaces of the plates, yielding means tending to force the central wedge member and the wedge plates longitudifor exerting pressure on said rollers to lock the wedge plates and central wedge member from movement with relation to each other and to said guideway.

' 3. A lockstitch outsole shoe sewing machine having, in combination, stitch forming devices, a work support, a presser-foot, mechanism for actuating the presser-foot to clamp and release the work, and means for locking the presser-foot comprising a locking wedge connected to the presser-foot, a cooperating wedge shaped member also connected to the presser-foot, but being capable of a slight longitudinal movement with relation to the locking wedge, a guideway in which said locking wedgeand wedge shaped member are mounted, and means for locking said wedge and wedge shaped member from movement with relation to each other and to said guideway.

4. A lockstitch outsole shoe sewing machine having, in combination, stitch forming devices, a work support, a presser-foot, mechanism for actuating the presser-foot to clamp and release the work, and means for locking the presser-foot comprising a locking wedge connected to the presser-foot, a cooperating wedge shaped member also connected to the presser-foot, but being capable of a slight longitudinal movement with relation to said locking wedge, a guideway in which said locking wedge and wedge shaped member are mounted, a plurality of locking rollers interposedbetween the locking wedge and the wedge shaped member, and means for exerting pressure on said rollers to lock the wedge and wedge shaped member from movement with relation to each other and to said guideway.

5. A lockstitch outsole shoe sewing machine having, in combination, stitch forming devices, a work support, a presser foot, mechanism for actuating the presser-foot to clamp and release the work, and means for locking the presser-foot comprising a locking wedge connected to the presserfoot, a cooperating wedge shapedmember also connected to the presser-foot and being capable of a slight longitudinal movement with relation to said locking wedge, a guideway in which said locking wedge and wedge shaped member are mounted, a spring interposed-between the locking wedge and wedge shaped member tending to force the wedge shaped-member to the limit of its relative longitudinal movement, and locking means inter posed between the wedge and wedge shaped member for locking the wedge and wedge shaped member from movement with relation to each other and to said guideway. 6. An outsole shoe sewing machine having, in combination, stitch forming devices, a work sup port, a presser-foot, means operating on stopping the machine to raise the presser-foot, and means conveniently accessible by the operator for adjusting said means to vary the height to which the presser-foot is lifted.

7. An outsole shoe sewing machine having, in

combination, stitch forming devices, a work supprising a constant throw actuating lever, a pres- 8. An outsole shoe sewing machine having, in

combination, stitch forming devices, a work support, a presser-foot, presser-foot locking mech-- tion, stitch forming devices, a work support, a

presser-foot, mechanism for actuating the presser-foot to clamp and release the work, and

means forlocking the presser-foot comprising a pin connected to the presser-foot, a. guideway extending at right angles to the pin, locking members in the guideway surrounding and being capable of slight movement transversely with relation to the connecting pin, means for intermittently clamping the locking members against movement relatively to each other and to said guideway and a spring acting between the looking members to force the members to the limit of their respective movements in opposite directions with relation to the connecting pin.

10. A shoe sewing machine having, in combination, stitchforming devices, a work support, a presser foot, mechanism for actuating the presser-foot to clamp and release the work, and means for locking the presser-foot comprising a pin connected to the presser-foot, a guideway extending at right angles to the pin, a pair of locking members in the guideway surrounding and being capable of slight motion transversely with relation to the connecting pin, a central locking member between said pair of locking members, means for intermittently forcing said cencombination, a curved hook needle and'a curved awl arranged always to lie in a common plane, a work support and a presser-foot acting to grip the work between them and to feed it past the needle and awl, a member connected to the presser-loot, and means for locking the presserfoot in contact with the work comprising a wedge and a wedging device arranged automatically to grip the member connected to the presser-footand to hold the latter against rising from the work.

combination, a curved hook needle and a curved awl arranged alwaysto lie in a common plane, a work support and a presser-foot acting to grip the work between them and to feed it past the needle and awl, a member connected to the presser-foot, and means for locking the presser- 12. A lockstitch sewing machine having, in

foot in contact with the work comprising a series of rolls arranged between the member which is connected to the presser-foot and another member arranged side by side therewith, and automatic means for forcing the rolls to lock the said two members together. i

13. An outsole shoe sewing machine having, in combination, stitch-forming devices including a. needle and an awl, a work support, a presserfoot, a pull-ofi', mechanism for actuating the presser-foot to clamp and release the work, ad.- justable mechanism for actuating the pull-ofl, a presser-foot spring, a rotatable sleeve on which the spring acts to yieldinglyengage the presserfoot with the work, a shaft within the sleeve for adjusting the pull-off actuating mechanism, and a clamp for securing the shaft in fixed angular relation to the sleeve.

14. An outsole shoe sewing machine having, in combination, stitch-forming devices including a needle and an awl, a work support, a presserfoot, :1 pull-01f, mechanism for actuating the presser-foot to clamp and release the work, adjustable mechanism for actuating the pull-off, a presser-foot spring, a rotatable sleeve on which the spring acts to yieldingly engage the presserfoot with the work, a shaft within the sleeve for adjusting the pull-off actuating mechanism, a clamp for securing the shaft in fixed angular relation to the sleeve, and cooperating scale and pointer means carried by the sleeve and shaft to indicate the relative angular relation thereof.

JOSEPH GOULDBOURN. THOMAS AUBREY KESTELL. FRANK BYCROFT KEALL.

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