US2119492A - Feed mechanism for sewing machines - Google Patents

Description

May 31, 1938. G. SAUER ET AL FEED MECHANISM FOR SEWING MACHINES 5 Sheets-Sheet 1 Filed NOV. 30, 1955 E g s, Q A (q W1 TNESSES:

INVENTORS qwryc fiauzrh Clamme 6.512231%,

7 WORNEYS.

May 31, 1938. G. SAUER ET AL 2,119,492

FEED MECHANISM FOR SEWING MACHINES Filed Nov. 50, 1935 5 Sheets-Sheet 2 WITNESSES: 51 A INVENTORS:

6 .Ge ryeSauerALCZaTenceCSIaitk,

BY I"! I WQMZM/ ATTORNEYS May 31, 1938. R ET AL 2,119,492

FEED MECHANISM FOR SEWING MACHINES Filed Nov. 50, 1935 3 Sheets-Sheet 3 WITNESSEL IN VEN TORS:

A TTORNEYS.

Patented May 31, 1938 UNITED STATES- FEED MECHANISM FOR SEWING MACHINES George Sauer, Berwyn, and Clarence C. Smith,

Chicago, Ill., assignors to Union Special Machine Company, Chicago, 111., a corporation of Illinois Application November 30, 1935, Serial No. 52,306

17 Claims.

This invention relates to feed mechanism for sewing machines; and it is more especially concerned with means for adjusting such mechanism.

The aim of our invention is to enable quick and accurate adjustment of feed mechanism of sewing machines, particularly reversible feed mechanism such as disclosed in U. S. Patent No. 2,035,508 granted on March 31, 1936 to the present .applicants embodying a rotativelyshiftable shaft capable of regulation to determine formation either forwards or backwards of stitches of different lengths.

The foregoing objective we realize in practice, as hereinafter more fully disclosed, through provision of an adjusting-means wherein, to effect reversals of the feed mechanism and variations in stitch length, a fixed abutment member having an opening with side edges at an angle to each other cooperates with a stop member movable from side to side from a central neutral position in said opening as well as toward and away from the apex of the angle; and wherein an indexing means visibly indicates the length of the stitches formed for the different settings of the mechanism.

Other objects and attendant advantages will appear from the following description of the drawings, wherein Fig. I is a fragmentary plan view conveniently embodying the feed adjusting means of our invention, portions of the frame of the machine having been broken out to expose parts which would otherwise be hidden.

-Fig. H is a fragmentary side elevation of the machine.

Figs. III and IV are fragmentary detail sectional views taken as indicated respectively by the arrows III-III and IVIV-in Fig. II.

Figs. V, VI and VII are detail views showing the adjusting means in different positions of adjustment; and

Fig.- VIII is a view corresponding to Fig. II showing an alternative embodiment of our invention.

- With more detailed reference first more particularly to Figs. I and 11 of these illustrations, I designates the bed plate or work support of the machine. Rising from the work support at one end, is the usual hollow standard 2 wherewith is integrally formed thehorizontal arm 3 which overhangs said work support, and in which is journaled the main shaft 4 of the machine having a combined hand and belt wheel 5 secured to its projecting rear end.

The reversible feed mechanism herein shown is generally of the construction featured in the patent hereinbefore referred to and, as shown, comprises a feed shaft 6 which is suitably journaled beneath the work support I, and which is actuated, through interposed drive connections (not illustrated) from the main shaft 4. Mounted on the shaft 6 is an eccentric 1, having associated therewith, a strap rod 8 composed of two telescoping parts or components 8a and 8b of which the latter is connected by a screw 9 to a yoked rocker I on a shaft I I having its ends journaled in spaced pendant bearing lugs-I2 and I3 of the work support I. The rear end of the feed bar designated I4 is pivotally connected at I "to the swinging end of the rocker I0 while at its forward end, said bar carries the usual feed dog I6, of which the toothed portions operate in slots I! of the throat plate l8 of the machine. The eccentric I is thus instrumental, through the strap rod 8, the rocker I0, and the bar I4, in imparting the back and forth feed movements to the feed dog I6. Another eccentric I9 on the shaft 6 functions, through its strap 20, to impart the necessary up and down or hit movements to the feed bar I4 exactly as described in Patent No. 2,035,508, hereinbefore referred to. Also journaled beneath the work support I and extending parallel with the shaft 6, is a feed regulating shaft 2I whereof the right hand end extends into an oil reservoir 22 immediately beneath and communicating with the hollow of the standard 2. To the left hand end of the regulating shaft 2I is secured an arm centric strap rod 8. By rotatively shifting the shaft 2| in opposite directions to different set positions, it is possible to reverse the action of the feed mechanism as well as to effect variations in the direction and length of the feed stroke of the feed dog I6 exactly as described in Patent No. 2,035,508.

The feed control means 'wi'th'which this invention is more especially concerned, includes a control shaft 26 extending transversely of the hollow of the standard 2 as shown in Fig. I. Clamped to this control shaft 26 within. the standard 2 is an arm 21, which, by means of a link 28, is coupled with an arm 29 clamped to-the inner end of the regulating shaft 2!. As shown,-the control shaft 26 extends to the exterior through a bearing boss 30 on the front wall 3| of the hollow standard 2, and to its protruding end is 'a'fiixed a control device having the form of a lever 32 with a roughened finger grasp 33. The hub 34 of the control lever 32 is comparatively large and is formed with a frontal open circular hollow 35, see Fig. III. Free on the control shaft 26 within the hollow 35 of the lever 32 is an adjusting member in the form of an eccentrically disposed circular cam 36 preferably with a finely serrated circumferential edge 31, see Fig. V. The hollow 35 of the lever hub 34 is closed by a circumferentially knurled discous dial 38 with numbered circumferential graduations for coordination with a pointer 39 on the control lever 32 to indicate the stitch lengths for different adjustments of the cam 36, said dial being connected to the cam by a dowel pin 40 and being held in place by a headed screw 4| threaded into the end of the control shaft 26. Axial shifting of the control shaft 26 1 is prevented through engagement of the diametrically reduced portion 42 of the hub 34 on the manipulating lever 32 with the outer face of the bearing boss 39, and by a collar 43 on said shaft within the hollow of the standard 2, between which collar and the inner face of said bearing boss, is introduced a friction washer 44. -Disposed in a longitudinal bore 45 of the manipulating lever 32 is a plunger pin 46 (Fig. III) which is yieldingly urged downward by a spring 41 whereof the upper end abuts a screw 49 threaded into the top of the bore for maintenance of the chisel end 50 of said pin in engagement with the serrated edge 31 of the cam 36. 2 by screws 5| is an abutment member in the form of a plate 52 which is apertured to fit about the reduced portion 42 of the lever hub 34, said plate having an opening 53 above the control shaft 26 with side edges 55 and 56 at an angle to each other and converging away from said shaft. Into the opening 53 of the plate 52 extends a cooperative stop 51 projecting laterally from the plunger pin 46. Asshown in Fig. III, the stop 51 is in the form of a stud which is secured in place by a screw 58 axially in the top of the plunger pin 46. From Fig. III it will moreover be noted that the stud 51 is flattened for engagement against rotation in a longitudinal guide slot 59 at the back of the control lever 32.

To adjust the feed mechanism, the dial 38 is rotated in one direction or the other with attendant shifting of the stop projection 51 under the action of the cam 36 up or down along the control lever 32 and toward or away from the apex of the angular opening 53 in the abutment plate. Obviously, by such shifting of the stop projection 51 the extent of swing allowed the control lever 32 will be either increased or decreased by virtue of the upward convergence of the stop edges 55 and 56 of the plate 52, with consequent impartation of correspondingly varied movements'to the regulating shaft 2| through the control shaft 26 and the interposedconnections 21, 28, 29, and change in the feed stroke of the feed dog l6. By coordination of the graduations on the dial 38 with the pointer 39 on the control lever 32, a definite stitch length for different settings of the feed mechanism will be indicated. As the control lever 32 is swung to the right of a central vertical neutral position in respect to the opening in the abutment plate as in Fig. V, the feeding will be forward, while when said lever is swung to the left as in Fig. VI, the action of the feed mechanism will be reversed without change however in the stitch length. In Figs. V and VI, the cam 36 is adjusted for the purpose of exemplification, with the stop 51 positioned low on the control lever 32 for determination of relatively large stitches; whereas in Fig. VII said desired variation of stitch, length.

' around the dial.

Aflixed to the side of the standard cam is positioned with the stop projection high on the control lever for determination of relatively small stitches. For use with the form of adjusting cam 36 shown in Figs. I-VII, the graduations on the dial are preferably finely spaced and consecutively numbered in opposite directions from a zero point to definitely indicate the different stitch lengths.

In order to prevent accidental disturbance of the feed mechanism in adjusted positions, we have provided a brake means to frictionally engage the regulating shaft 2|. As shown in Figs. II and IV, this brake means is in the form of a split clamp 66 with an upward shank projection 6| engaging an opening 62 in the work support of the sewing machine, the frictional restraint imposed upon the regulating shaft 2| by the clamp being adjustable by means of a screw 63.

When a finer feed stroke is desired, we provide an adjusting cam of spiral configuration such as shown at 36a in Fig. VIII, whereof substantially the whole periphery can be utilized to effect the In this instance, the graduations are equally spaced to definitely indicate stitch lengths as in the first embodiment, but the numbering is continuous In order to preclude the necessity for repetitive description, all other elements in the alternative embodiment of Fig. VIII having their counterparts in thedescribed embodiment, have been identified by the same reference characters except for the addition in each instance of the letter at for the purpose of distinction.

The adjusting cams herein shown are to be considered as typical of other shapes, which, with in the scope of the appended claims, can be uti lized to effect changes in the stitch lengths as may be desired. It is also to be understood that the arrangement of the indicia on the dials may be arbitrary, instead of being arranged to definitely indicate the stitch lengths as hereinbefore described. By substitution of a shorter arm for the arm 21 it is possible to arrange the feed mechanism for operation always in one direction and still vary the stitch length with the aid of our improved control means. As another alternative in'the arrangement of the mechanism, the arms '21 and 29 may be shifted on the respective shafts,

so that a longer stitch will be formed when the control lever is swung to one side of its neutral position than when it is swung to the other side of said neutral position. For example, with the regulating shaft 2| in neutral position, by shifting the arm. 21 rearward (Fig. I) axiallyof the shaft 26 without change in its angular position in relation to the latter, or by shiftingthe arm 29 leftward (Fig. II) axially of the shaft 2| (with incidental change in the relative position of the the fixed stop 55 is increased. As a consequence,

when the lever 33 is swung to the right, a shorter stitch will be'formed than when it is swung to the left. Similarly, shifting of the arm 21 forward (Fig. I) axially of the shaft 26, or the arm 29 rightward (Fig. II) axially of the shaft 2|, it is possible to determine an angular neutral position for the control lever 33 to the. left of the vertical. By the latter change, a shorter stitch will be formed whenthe'control lever is swung to the left in respect to the neutral as far as permitted by the fixedstop 55. and a longer stitch formed when said lever is swung to the right as'far as permitted by the-fixed stop 56. Thus through our improved control means, any desired proportioning of the stitch length in opposite directions of feeding may be obtained, and the feeding mechanism adjusted for stitch length in the manner disclosed in Patent No. 2,035,508 without change in the proportioning determined by the setting of said lever as above explained.

Having thus described'our invention, we claim:

1. In feed mechanism for sewing machines, a stitch length controlling device, means establishing limits for movements of said device corresponding to predetermined stitch lengths, said means comprising cooperative stop members, one

of said members having an opening with edges means comprising cooperative stop members, one

' of said members having an opening with edges disposed at an angle toeach other, and. the other stop member being relatively movable in said opening and relatively adjustable toward and away from the apex of said angle, and means indicating the stitch length determined by the relative adjustment of said members.

3. In reversible feed mechanism for sewing machines, a stitch length control means comprising a control lever, a stop projection adjustable along the lever, a fixed member having an opening with side edges at an angle to each other to function as abutments in cooperation with the stop projection on the control lever to variantly limit the movements of the latter to opposite sides of a central neutral position in respect to said opening, and means for adjusting the stop projection along the control lever.

4. In reversible feed mechanism for sewing machines, stitch length control means comprising a control lever, a stop projection movable along the lever; a fixed member having an opening.

with side edges at an angle to each other to function as abutments in cooperation with the stop projection on the control lever to variantly limit the movements of the latter to opposite sides of a central neutral position in respect to said opening, and means for adjusting the stop projection along the control lever including a cam rotatively adjustable about the fulcrum axis of said lever.

5. In reversible feed mechanism' for sewing machines, a stitch length control means comprising a control lever, a. stop projection movable along the length of the lever; a fixed member having an opening with side edges at an angle to' the lever, a fixed member having an opening with side edges at an angle to each other to function as abutments incooperation with the stop projection on the control lever to variantly limit the movements of the latter to opposite sides of a central neutral position in respect to said opening,'means for adjusting the stop projection along the lever including a cam rotatively adjustable about the fulcrum axis of said lever, and a dial moved with the cam, said dial having graduations for coordination with a pointer to indicate stitch lengths corresponding to diflerent settings of the control means.

7. In reversible feed mechanism for sewing machines, stitch length control means comprising a control lever; a lateral stop projection carried by a spring-pressed plunger pin shiftable endposition in respect to said opening, and a cam rotatably adjustable about the fulcrum axis of the control lever and operative to shift the spring pressed plunger pin carrying the movable stop projection.

8. In reversible feed mechanism for sewing machines, stitch length control means comprising a control lever; a lateral stop projection carried by a spring-pressed plunger pin shiftable endwise longitudinally of the control lever, a fixed memher 'having an opening with side edges at an angle to each other to function as abutments in cooperation with the stop projection on the control lever to variantly limit the movements of the latter to opposite sides of a central neutral position in respect to said opening, and a cam rotatably adjustable about the fulcrum axis of the control lever and having a serrated circumferential edge engaged by. a chisel edge at the lower end of the spring pressed plunger pin carrying the movable stop projection on said lever.

9. In reversible 'feed mechanism for sewing machines, a rotatively shiftable regulating shaft, and control means for said shaft including a control lever, a stop projection movable along said control lever, a fixed member having an opening therein with side edges disposed at an angle to each other to function as stops in cooperation with the stop projection to limit the movements of the leverto opposite sides of a central neutral position in respect to said opening.

10. In reversible feed .mechanism for sewing machines, a rotatively shiftable regulating shaft, and control means for said shaft including a control lever, a stop projection movable along said control lever, a fixed member having an opening therein with side edges disposed at an angle to each other to function as stops in cooperation with the stop projection to limit the movements of the lever to opposite sides of a central neutral position in respect to said opening, and clamp brake means frictionally engaging the regulating shaft to hold the stitch length control against accidental disturbance in adjusted positions.

11. In feed mechanism for sewing machines, a stitch length controlling device comprising a control lever; and means establishing various limits of movement for the control lever, including a stop member adjustable along the length of said lever, and abutments 'to cooperate with the stop in all positions of adjustment of the latter, said abutments being so arranged that the movement of the control lever is reduced as the stop is adjusted away from the fulcrum of the said lever.

12. In feed mechanism for sewing machines, a stitch length controlling device comprising a control lever; and means establishing various limits of movement for the control lever, including a stop member adjustable along the length of the lever, means coaxial with the fulcrum of said lever for adjusting the stop, and abutments to cooperate with said stop.

13. In feed mechanism for sewing machines, a stitch length controlling device comprising a control lever; means establishing various limits of movement for the control lever including a stop adjustable along the length of the lever, a member rotatable about the fulcrum axis of the lever for adjusting the position of the stop, means coordinated with the adjusting member to indicate the setting of the latter for stitch lengths, and abutments to cooperate with said stop.

14. In feed mechanism for sewing machines, a stitch length controlling device comprising a control lever; and means establishing various limits of movement for the control lever including a stop member adjustable along the length of the lever, a rotatable member coaxial with the fulcrum of said lever for adjusting the stop, a dial on the rotatableadjusting member to indicate the setting of the stop according to stitch lengths, and abutments to cooperate'with said stop.

15. In feed mechanism for sewing machines, a regulating shaft; a control shaft at an angle to the regulating shaft, lever arms independently position to reverse the direction of feeding; and 10 means whereby different neutral positions may be determined relative to the fixed abutments such that the swing of the lever in one direction in respect to neutral is greater than in the other,

with attendant determination of a long stitch 15 in one direction of feeding and a short stitch in the opposite direction of feeding.

17. In feeding mechanism for sewing machines, a control lever; fixed abutments between which the lever is swingable through a neutral posi- 20 tion to reverse the direction of feeding; means whereby different neutral positions may be determined relative to the fixed abutments such that the swing of the lever in one direction in respect to neutral is greater than in the other, 25

with attendant determination of a long stitch in one direction of feeding and a short stitch in the opposite direction of feeding; and means where-- by the mechanism can be adjusted for stitch length without change in the proportioning of'30 the stitching in opposite directions of feeding under control of the lever.

GEORGE SAUER.

CLARENCE C. SMITH. 35

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