US2095450A

US2095450A - Sewing machine loop-taker mechanism

Info

Publication number: US2095450A
Application number: US121251A
Authority: US
Inventors: Myers Walter
Original assignee: Singer Co
Current assignee: Singer Co
Priority date: 1936-04-16
Filing date: 1937-01-19
Publication date: 1937-10-12
Anticipated expiration: 1954-10-12

Description

OctQlZ, 1 937. I w M YERs- I 1 1 smgmemxbama-mm TAKER MECHANISM Original Filed April 16, 1936 3 Sheefos-Sheet 1 Oct. 12, 1937. w. MYERS 2,095,450

SEWING MACHINE LOOP -TAKER MECHANISM Original Filed April 16, 19 36 3 SheetQ-Sheej 2 if a. I

1a In Oct. 12, 1937. w. MYERS,

SEWING MACHINE LOOP TAKER MECHANISM- Original Filed April 16, 1936 3 Sheets-Sheet 3 v aw w 1.; 6 A 17/0? Patented Oct. 12, 1937 SEWING MACHINE LOOP-TAKER MECHANISM Walter Myers, Bridgeport, Conn., assignor to The Singer Manufacturing Company, Elizabeth, N. J., a corporation of New Jersey Original application April 16, 1936, Serial No.

Divided and this application January 19, 1937, Serial No. 121,251

7 Claims.

This invention relates to improvements in stitch-forming mechanisms for sewing machines and has for its primary object to provide supporting and actuating means for a sewing machine loop-taker, more specifically of the verticalaxis rotary hook type, which is particularly adapted for high speed operation.

With the .above and other objects in view, as will hereinafter appear, the invention comprises the devices, combinations and arrangements of parts of a loop-taker actuating mechanism described in connection with the accompanying drawings which illustrate a preferred embodiment of the invention and in which:

Fig. 1 represents a vertical longitudinal section, partly in front elevation, ofasewing machine containing the present improvement. Fig. 2'is a bottom plan view of the machine. Fig. 3 represents an enlarged transverse section of the bed-plate, substantially on the line 3--3 of Fig. 2. Fig. 4 represents a perspective view, partly in section, of one of the rotary-hook brackets, including a portion of the rotary hook mechanism thereof. Fig. 5 is a top-plan, partly in section, 25 of the adjacent rotary hook brackets. Fig. 6

represents a section of one of the rotary-hook brackets, in substantially a plane containing the vertical axis of the hook-shaft. Fig. 7 represents a horizontal section of the hook-bracket,

30 substantially on the line of Fig. 6.

As described in my co-pending patent application Serial No. 74,615, filed April 16, 1936, of which this application is a division, and as 11- lustrated in the accompanying drawings, the present invention has been embodied in a sewing machine having a frame comprising a worksupporting bed-plate I provided with left and right slide-plates 2 and 3 and with a throat-plate 4 between said slide-plates. Rising from one end projecting from the bracket-arm 8. The main shaft 8 is also journaled in a bearing bushing l2 and, at its end adjacent said bushing, carries a crank |3 connected by the usual link M with a needle-bar l5 carrying at its lower end a pair of .needles' l6 arranged abreast with respect to the direction of feed of the work.

The needle-bar I5 is journaled for vertical reof the bed-plate is the hollow standard 5 of aciprocation in a pendulous frame I1 pivotally hung upon a taper-headed fulcrum-pin I8 for.

j PATENT. OFFICE swinging movements within the head labout an 3 axis substantially parallel to the axis of rotation of the main-shaft 8, said fulcrum-pin being se-- cured by a screw I8 threaded into the head I.

Disposed below and adjacent the rearward edge of the bed-plate I, substantially parallel to the main-shaft 8, is a loop-taker. and feed-actuating shaft l9. Adjacent one end thereof, the shaft I9 is journaled in a ball-bearing sustained by a'bearing-lug 2| depending from the bed-plate At its opposite end, theshaft I9 is journaled in a bearing-bushing 22 secured in a lug 23 depending from the bed-plate and in termediate its ends the shaft I9 is journaled in I another bearing-bushing 24 secured in a lug 25 ends of the bearing-

bushings

22 and 24, are two' spiral-

gears

29 and 30 in driving engagement with spiral-gears 3| and 32, respectively, the gear ratios being such that the driven gears 3|, 32 are rotated at twice the speed of the

driving gears

29, 30. The driven gears 3|, 32 are carried by vertically disposed loop-

taker shafts

33, 34, respectively, said shafts being of similar construction and each carrying at its upper end a

looptaker

35, or 36, of the vertical-axis rotary hooktype. These loop-takers cooperate with the needles I6 in the formation of lock-stitches; the needle-thread loops seized by the loop-takers being each cast about a lower thread mass contained in a bobbin-case 31, journaled in the respective loop-taker and restrained against rotation therewith by a suitable stop-notch 38 at the under side of the throat-plate 4.

The loop-taker shaft 33 is journaled in verfrom a left-hand loop-taker'brackt 4|, said bracket 4| having at its rearward end a split bearing-boss 42 adjustably clamped -uponv the bushing 22 by a screw 43. At its forward e'nd,;fv the bracket 4| is provided with a foot44 having a rounded upper face secured by a screw 45 against a seat aiiorded by the horizontallytflattically spaced bearing-

lugs

39 and 40 projecting tened lower end of a lug 48 depending from the bed-plate I. The bracket-securing screw 45 passes through a slot 4! provided in the foot 44, said slot being elongated in a direction to provide for adjustment of the bracket 4i toward and from the path of needle reciprocation.

The loop-taker shaft 34 is likewise journaled in vertically spaced bearing-

lugs

48 and 49 projecting from a right-hand loop-taker bracket 58, said bracket 58 having at its rearward end a split bearing-boss 5i adjustably clamped by a screw 52 upon the bushing 24. At its forward end, the bracket 58 is provided with a foot 53 having an elongated slot 5d entered by a screw 55 which secures the foot 53 against a horizontal seat 55 formed by suitably recessing a lug 57 depending from the bed-plate I.

The loop-

taker shafts

33 and 34 are similarly journaled in the brackets H, 58. Referring more particularly to Figs. 6 and '7 of the drawings, the upper bearing-lug 48 of the bracket 58 has a vertical aperture 48'. Threaded into said aperture from the under side thereof is a bushing I53 secured in set position by a screw l54. The bushing I53 provides a seat for and serves to vertically locate an outer race-ring 58, which is preferably force-fitted to its seat and is thereby restrained against rotation. An inner race-ring 59 closely embraces the shaft 34 and is preferably caused to rotate with said shaft by a clutchball 68 disposed within said race-ring 59 and in a recess 8i peripherally provided in the shaft 34. The base of the recess BI is preferably a plane surface and is formed so that the depth of said recess, medianly of its length, is preferably substantially equal to the diameter of the ball 68, to provide for assemblage of the parts. Upon rotation of the shaft 34, the ball 68 will instantly grip the inner race-ring 58 and will induce rotation with the shaft of the inner racering. This arrangement facilitates securing the inner race-ring to its shaft and obviates the distortion of the parts likely to occur by employment of ring-securing screws. A series of bearing-balls 62 is interposed between the

racerings

58 and 59 in the usual manner to complete the upper ball-bearing of the loop-taker shaft 34.

Resting upon the inner race-ring 59 is an oilguard washer 63 which is undercut to overhang the outer race-ring 58 in spaced relation thereto, thereby providing a clearance-recess 64 above said race-rings for supplying lubricant to the bearing-balls 62. The washer 63 is held in place by an eccentric 65 formed or otherwise provided upon the shaft 36 directly below the loop-taker 36, said washer serving to guard against emission of lubricant from the upper end of the bearinglug aperture 48.

The eccentric 65 is embraced by the strap of a short pitman 68 pivotally connected by a stud-bolt B1 to a horizontally vibratory arm 68 of an angular opener-

carrier

68, 68. The arm 68 of the carrier is disposed in a suitably shaped cavity III provided in the upper face of the bracket 58, one end of said arm 68 being pivotally secured by a fulcrum-stud H fixed in the bracket 58 by a set-screw I2. disposed arm 69 of the opener-carrier extends above the bracket 58 and is horizontally grooved in its upper end to provide a seat for the shank of the usual opener-finger I3 adapted to engage intermittently and oscillate the bobbin-case 3?, thereby to open a thread-passage in the bobbincase rotation restraining means. The shank of the finger E3 is slotted to receive a finger-secur- The vertically ing .screw I4 and to provide for adjustment of said finger.

The lower end of the loop-taker shaft 34 is journaled in an aperture 49' provided in the bearing-lug 49, said aperture 49' being in vertical alinement with the upper lug aperture 48'. Similarly to the upper ball-bearing, the lower ball-bearing includes a series of balls I5 disposed between a fixed outer race-ring I8 and an inner race-ring H, the inner race-ring 11 embracing and being caused to rotate with the shaft 34 by a clutch-ball I8 disposed in a recess T9 peripherally provided in said shaft. The outer race-ring is vertically located by a bushing I55 threaded into the lower lug from the under side thereof, said bushing being secured in set position by a screw I 56. Overlying the lower ballbearing is an undercut oil-guard washer 80 similar to the upper-bearing washer B3 and defining a clearance-recess BI above the ball-bearing for supplying lubricant to the bearing-balls I5. The washer 80 is held in place by the hub of the driven gear 32, disposed between-the

bracketlugs

48, 49 and secured to the shaft 34 by a setscrew 82.

The journaling of the loop-taker shaft 33 in thebearing-

lugs

39, 48 of the bracket M and the bobbin-case opener mechanism actuated by said shaft 33 correspond in detail with the described journaling of the shaft 34 and its bobbincase opener mechanism. Accordingly, the parts have been correspondingly designated in the drawings, so far as illustrated in detail.

Lubricant is supplied to the bearings of the loop-taker shaftsfrom reservoirs carried by the respective loop-taker brackets and connected by separate conduits with the shaft bearings. Referring more particularly to Figs. 4 and 5 of the drawings, the bracket H, for example, is preferably integrally provided with a trapezoidal lubricant-supply reservoir 83 disposed adjacent to the opener-mechanism cavity 10 in said bracket. The rearward portion of the reservoir 83 is closed at the top by an overhanging roof-wall 83, which is preferably integral with the side walls of the reservoir and terminates short of the forward wall, thereby to provide a top opening 84 in the forward portion of the reservoir. The roof-wall 83 functions to retain lubricant within the reservoir 83 when the sewing machine is tilted back for access to the mechanism below the bed-plate I. Preferably, a lubricant-absorbent pad 85 is placed upon the bottom of the reservoir 83 to control the flow of lubricant therefrom.

The bottom of the reservoir 83 has an aperture 86 opening into an oil duct 81 provided in the bracket 4i below and extending horizontally crosswise of the front end of said reservoir. The outer end of the duct 81 is sealed by a plug 88 and its inner end is connected with a horizontal duct 88, provided in the bracket-bearing lug 39 and extending transversely of the duct 81. The outer end of the connecting duct 89 is sealed by a plug 58 and its inner end terminates in a reduced bore 89' communicating with the clearance-recess 64 above the shaft-bearing balls 62.

The bottom of the reservoir 83 has another aperture constituting the upper end of a vertical duct 9I provided in the bracket 4|. The lower end of said duct 8i opens into a horizontallytransverse bracket-duct 92 closed at its outer end by a plug 93. At its inner end, the duct 92 has a restricted bore 94 in the bracket-lug 48, said bore 94 communicating with the clearancerecess 8i above the shaft-bearing balls 15.

aoeaico before referred to and, as the present invention is not limited to any specific form of feeding mechanism, it is deemed uncssential to describe the same.

Having thus,set forth the nature of the in vention what I claim herein is:-

1. Loop-taker mechanism for sewing machines, comprising, a supporting bracket having vertically spaced bearing-lugs, a vertically disposed looptaker carrying shaft, ball-bearings infsaid lugs providing vertically spaced journals for said shaft, driving connections for rotating said shaft,-

a lubricant-supply reservoir in said'bracket adjacent to and connected with the upper of said ballbearings, and means for conducting lubricant from said reservoir to the lower of said ball-bearings. I

2. Loop-taker mechanism for sewing mach nes, comprising, a supporting bracket having vertical- 1y spaced bearing-lugs, a vertically disposed looptaker carrying shaft, ball-bearings in said lugs providing vertically spaced journals for said shaft, driving connections for rotating said shaft, a lubricant-supply reservoir upon said bracket having a roof wall closing the upper rearward portion of the reservoir and leaving the front portion of said reservoir open at the top, and means for conducting lubricant from said reservoir to said ball-bearings.

3. Loop-taker mechanism for sewing machines, comprising, a supporting bracket having vertically spaced bearing-lugs provided with vertically alined apertures, a vertically disposed looptaker carrying shaft peripherally provided with vertically spaced recesses, ball-bearings disposed in the apertures of said lugs and providing vertically spaced journals for said shaft, said ballbearings including outer race-rings fixed in the respective bearing-lugs and inner race-rings embracing said shaft recesses, clutch-balls disposed in said shaft recesses for effecting rotation of said inner race-rings with said shaft, and driving connections for rotating said shaft.

4. Loop taker mechanism for sewing machines, comprising, a supporting bracket having vertically spaced bearing-lugs provided with vertically alined apertures, bushings threaded into said lugs, a vertically disposed loop-taker carrying shaft, ball-bearings disposed in the apertures of said lugs and providing vertically spaced journals for said shaft, said ball-bearings including outer race-rings engaged and vertically located by said bushings,'means for securing said bushings, and driving connections for rotating said shaft.

5. Loop-taker mechanism for sewing machines, comprising, a supporting bracket having vertically spaced bearing-lugs provided with vertically alined apertures, a vertically disposed looptaker carrying shaft, ball-bearings disposed in the apertures of said lugs and providing vertical- 1y spaced journals for said shaft, means includinga bushing threaded into one of said lugs for locating said ball-bearingsin vertically spaced relationship, and driving connections forrotating said shaft.

6. Loop-taker mechanism for sewing machines, comprising, a supporting bracket having vertically spaced bearing-lugs provided with vertical .ly alined apertures, a vertically disposed looptaker carrying shaft, ball-bearings disposed in the apertures of said lugs and, providing verti cally spaced journals for said shaft, bushings disposed in said bearing-lug apertures below and in engagement with said ball-bearings, and driving connections for rotating said shaft.

7. Loop-taker mechanism for sewing machines, comprising, a supporting bracket having vertically, spaced bearing-lugs provided with vertically alined apertures, a vertically disposed looptaker carrying shaft, ball-bearings disposed in the apertures of said lugs and providing vertically spaced journals for said shaft, a bushing disposed in one of said bearing-lug apertures and providing a positioning shoulder for one of said ball-bearings, and driving connections for rotating said shaft.

WALTER.