US1543945A - Feeding mechanism for sewing machines - Google Patents

Description

June 30, 1925. 1 1,543,945 J. R. MOFFATT- v FEEDING MECHANISM FOR SEWING MACHINES FiledApril 19, 1921 3 Sheets-Sheet 1 a; a 1 j.

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v J. R. MOFFATT FEEDING MECHANISM FOR SEWING MACHINES Filed April 19 1921 3 Sheets-Sheet 2 June 30, 1925..

' J. R. MOFFATT FEEDING MECHANISM FOR SEWING MACHINES 3 Sheets-Sheet 5 File d April 19. 1921 Patented June 30, 1925.

. UNITED STAT PATENT OFFICE.

JAMES R. MOFFATT, or CHICAGO, ILLINoIs, AssIeNoa'ro UNIoN SPECIAL MACHINE COMPANY, or CHICAGO, ILLINoIs, A CORPORATION or ILLINoIs.

FEEDING MECHANISM FOR SEWING MACHINES.

Application filed Apri1'19, 1921. Serial No. 462,571.

To all whom it may concern:

Be it known that I, JAMES R. luOFFATT, a citizen of the United States, residing at Chicago, in the county of Gook, State of Illinois, have invented certain new and useful Improvements in Feeding Mechanisms for Sewing Machines, of which the following is a description, reference being had to the accompanying drawing and to the figures of reference marked thereon.

The invention relates to new and useful improvements in feeding mechanisms for sewing machines, and more particularly to a feeding mechanism which includes a feed dog mounted beneath the work support andoperating through, slots in the work sup:.

port for engaging and feeding the material.

v An object of the invention is to provide a feed .dog supporting and operating means feed dog supporting, means beneath the work support;

which permits the feed dog to be shifted laterally, orin a direction at right angles to the line of feed, to center the fabric engaging portions thereof in the slots through which they operate.

A further object of the invention is to provide a feeding mechanism wherein the means for supporting and operating the feed dog is so constructed as to permit the working position of the fabric engaging portions of'the feed dog to be centered in the feed slots through which they operate; or, in other words, to be shifted in the line of feed.

These and other objects will in part be obvious and will in part be hereinafter more fully disclosed.

In the drawings which show by way of illustration one embodiment of the invention Figure 1 is a view in top plan of a portion of a sewing machine having my improvement embodied therein, and with a part of the work support broken away to show the Figure 2 is a View partly in vertical. section and partly in elevation from the left hand end of the machine; I

Figure '3 is a View partly in section and partly in rear elevation of the same;

Figure 4- is a longitudinal sectional view on the line 44 of Fig. 1;

Figure 5 is an enlarged view, partly in section, of the crank pin disc on the main shaft;

' length.

Figure 6 is a perspective View, with parts separated, showing feed rocker, feed bar and feed dog; and i Figure 7 is a section on line 77 of Figure 6.

The invention is directed broadly to a feeding mechanism of the type wherein a feed dog is mounted beneath the work support and is provided with fabric engaging sections operating through slots in the work support or-throat plate forming a part of -the work support. This feed dog is carried by a feed bar which is pivotally connected to a feed rocker. The feed'rocker is provided with spaced supporting lugs in which is mounted a bar or shaft to which the feed bar is fixedly connected. This bar or shaft is secured from endwise movements in the lugs by adjustable collars. By loosening the collars or loosening the connection between the feed bar and the bar or shaft mounted in the lugs, the entire feed bar may be moved laterally, or in a direction at right angles tothe line of feed, for ositioning the fabric engaging sections of the feed dog centrally of the slots in the throat plate.

The feed rocker is operated by an arm connected to a crank on the main shaft. On said crank is an eccentric sleeve which is clamped in the end of the arm and by adjusting this sleeve the working position of the fabric engaging sections of the feed dog may be shifted back and forth and thus centered relative to the longitudinal length of the slots in the throat plate.

Referring more in detail to the drawings, my improved feeding mechanism is shown as applied to a sewing machine having a bed plate 1, on which is mounted a. work support 2. The work support 2 is provided with a throat plate 3 which is secured to the work support by suitable screws fr-4:, and, in fact, becomes a part of the work support. This throat plate is provided with. needle'holes 5-5 and with feed slots 6, 7 and 8. Mounted beneath the work support is a feed dog 9, which in turn is provlded with fabric engaging sections 10, 11- and 12. These fabricengaging sections respec-- tively extend through the slots 6, 7 and8, and engage the fabric resting on the work support and throat plate to feed it a stitch I This feed dog 9 is provided with a shank," 13, which is slotted at 14. The shank 13 fits in a recess in a feed bar 15,and a -screw 16 passing through the slot 14 rigidly clamps the shank of the feed dogin the. recess in the feed bar. Attached to the feed bar 15 is'a plate 17.- The feed bar carries a hardened plate 18, which rests on an eccentric 19, carried by the main shaft 20. The plate .17 engages the underface of this eccentric the shaft 23 there is a collar 26, which is secured to the'shaft 23 by a set screw 27, which is not spotted, so that said collar 26 may be shifted endwise of the shaft 23. At the opposite end of the shaft 23 there is a similar collar 28, whichis secured to the shaft by a set screw 29. These collars bear against the outer faces respectively of the lugs 2525.

Said feed rocker 21 is also provided with upwardly extending lugs 3030, in which is mounted a shaft 31, so that said shaft/may freely turn in said lugs 30. The feed bar 15 is provided with integral sleeves 32-32,

which are mounted on this shaft 31 and these sleeves are secured to the shaft by means 'of set screws 33, so that thefeed bar is fixed to the shaft 31. On the right hand end 0f.the shaft 31 there is a collar 34'which is secured to the shaft by. a set screw 35 which is not spotted, so that said collar may be shifted endwise of the shaft 31. At the opposite end of the shaft 3lthere 'is a similar collar 36, secured thereto by a set screw 37 These collars bear against the outer faces respectivelyof the lugs 3030. I 5

Attention is particularly called to the fact that the distance betweenthe outer faces of the lugs 2222 is considerably less than the distance between the inner faces of the bearing lugs. 2525, so that by loosening the collars 26 and 28, the shaft 23 may be shifted Qendwise in the lugs 2525 and thus the whole feed rocker shifted endwise or transversely of the direction of its rocking movemerit and the direction of movement of the feed dog by the sewing machine. Itwillb'e readily seen that this endwise shifting of the:

feed rocker results in a lateral shifting of the feed bar and through this lateral shifting of the feed bar the fabric engaging sections 10, 11 and 12 of the feed dog may be centered in the, slots 6, 7 and 8, in which they work. This is a great advantage as it eliminates a 7 .close milling operation between the lugs feed bar or 2222 and 25-25, or the bending of the the filing away of the shank of the feed dog, or in some other way the re.-

" shaping or reforming of the metal to penter shifted laterally and thus the fabric engaging sections of the feed dog properly centered in the slots in the work support.

The feed rocker is oscillated to impart back and forth movements to the feed dog.

by means of an integral arm 38. This arm 38 is split at 39, as is clearly shown in Figure 6, and is provided with a cylindrical recess 40, into which the split end leads. Located in this cylindrical recess 40 is a split sleeve 41, which has :rflanged head 42 notched, as indicated at 43. Said sleeve is I I split, as indicated at 44, and has a cylindrical opening 45 which is eccentrically disposed relative to the center of. the sleeve and the center of the recess 40. The split end'of the arm'38 carries a set screw 46 by means of which the sleeve 41 may be fixedly clamped in the outer end. of the arm 38. By loosening the. screw, it will be apparent that the sleev'emay be readily adjusted through the' aid of the notches in the flange carried thereby. Clamped in said cylindrical opening 45 by the screw 46 is a pivot pin 47, the center of which is, of course, eccentric to the center of the sleeve 41. Loosely engaging the pivot'pin 47. is one end of al'ink v48 and said link .at its other end engages a crank pin 49, carried by a plate 50,-which is mounted to slide back and forth in a slot 51 in a disc 52 secured to the end of the mainshaft 20. A screw 53 is threaded through said plate 50 and is held from endwise movement by a 'bracket piece 54, lying between collars carried by the screw, and said bracketv piece is secured tothe disc 52 by meansof screws 55. By turning thescrew 53 the crank pin 49 is shifted toward and from the center of the shaft for varying the strokeof the feed dog. When the pivot *pin 47: is shifted through the adjusting of the sleeve 41, the arm 38 will be'swung toward or from the crank pin 49, a'nd'the swinging of the arm 38 will change slightly the working position of the fabric engaging sections of the feed 7 dog. If, therefore, when the parts are assembled,.it is found that the feed dog is working too close to the front end of the slots 6, 7 and 8,.then this pin 4''( is shifted so as. to -move,the working position rearwardly chine is set up, the fabric engaging sections of the feed dog may be centered in the feed slots in the work support, so that they will move back and forth without binding against the side walls of the slot; and, on the other hand, the stroke of the feed dog may be shifted so that the center of the longitudinal stroke of the feed dog will be centered with the longitudinal length of the slots.

It is obvious that minor changes in the details of construction and the arrangement of parts may be made without departing from the spirit of the invention, as set forth in the appended claims.

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

1. A feeding mechanism for sewing machines including in combination a work support having feed slots therein, a feed dog mounted beneath the work support and having fabric engaging sections extending through said slots, means for raising and lowering the feed dog, means for moving the feed dog back and forth, said last named means including adjustable devices for varying the working position of the fabric engaging sections of the feed dog without changing the length of the feed stroke,

whereby the same may be centered longi tudinally of the respective slots in which said sections operate.

2. A feeding mechanism for sewing machines including in combination a, work support having feed slots therein, a feed dog having fabric engaging sections workin in said slots, a feed bar supporting said feed dog, means for raising and lowering the feed bar, a feed rocker for moving the feed bar back and forth, means for oscillating said rocker, devices connecting the feed bar to the-feed rocker, and devices for supporting said feed rocker, one of said devices being manually adjustable, whereby the feed bar may be shifted laterally for centering the fabric engaging sections thereof in their respective slots, and means whereby the working position of the fabric engaging sections of the feed dog may be shifted longitudinally of the feed .slots for centering said sections longitudinally of the respective slots in which they operate and without varying the length of the feed stroke.

3. A feeding mechanism for sewing machines including in combination, a work support having feed slots therein, a feed dog having fabric engaging sections working in said slots, a feed bar carrying said feed dog, means for raising and lowering the feed bar, a feed rocker, an'arm integral with said feed rocker, a pin carried ,by the outer end of said arm, a link connected to said pin for oscillating the arm for moving the feed dog back and forth, and means whereby said pin may be shifted in said arm forvarying the working position of the fabric engaging sections of the feed dog in their respective slots. I

4. A feeding mechanism for sewing ma chines including in combination, a work support having feed slots therein, a feed dog having fabric engaging sections working in said slots, a feed bar carrying said feed dog, means for raising and lowering the feed bar, a feed rocker, an arm integral with said feed rocker, a sleeve adjustably mounted in the outer end of said arm, a pin eccentrically carried thereby, means for engaging said pin for oscillating the arm, and means for clampingsaid sleeve in an adjusted position.

5. A feeding mechanism'for sewing inachines including in combination, a work support having feed slots therein, a feed dog 30 having fabric engaging sections working in said slots, a feed bar carrying said feed dog, means for raising and lowering the feed bar, a feed rocker, an arm integral with said feed rocker, a split sleeve mounted in the outer end of said arm, the outer end of said arm being split' and having a clamping screw for clamping said sleeve, said sleeve having an opening eccentrically located therein, a pin mounted in said open- 5 ing, and a link connected to said pin for oscillating said arm. I

i 6. A feeding mechanism for sewing machines including in combination, a work support having feed slots formed therein, a 9

feed dog havlng fabricv engaging sections working in said slots, a.nd means for supporting and actuating said feed dog including devices whereby the fabric engaging sections may be shifted laterally in their re- 1 spectiveslots for centering the same relative to the slots and whereby the working position of said fabric engaging sections may be shifted longitudinally of their respective slots for centering the same longitudinally of the slots.

7. A feeding mechanism for sewing machines including in combination, a work support having feed slots therein, a feed dog having Iabric engaging sections working-in saidslots, a feed bar carrying said feed dog, means for raising and lowering the feed bar, a feed rocker, an arm integral with said feed rocker, a split sleeve mounted in the outer end of said arm, a pin in said sleeve, a link connected to said pin for oscillating said arm on the feed rocker, and a clamping screw for the outer end of said arm for clamping the pin in the split sleeve and'clampingthe sleevejjii-n said split arm.

8.-'A.feeding mechanism for sewing machines including in combination, a feed dog, a feed bar, a feed rocker to'which said bar is connected, a bed plate having spaced lugs, a shaft mounted in said lugs, collars on the 7 of a bed plate, a feed rocker mounted therec outer ends of said shaft and engaging respectively the outer faces of said lugs to prevent endwise movement of said shaft-and permitting said shaft to be adjusted endwise and held in adjusted positions, said feed rocker having sleeves through which said shaft extends, said sleeves being fixed to the shaft and having their outer faces a less distance apart than the distance between the inner faces of the lugs carrying said shaft. 7

9. In a sewing machine, the combination 011, means for oscillating said 'feed rocker, a

" feed dog, a feed bar carrying said dog, said feedbar having spaced sleeves, said feed rocker having spaced sleeves, a shaft passing through said sleeves for connecting the feed bar to the feed rocker, said sleeves on the feed bar being fixed to the shaft, and collars .adjustably mounted on the outer ends of said shaft and bearing against the outer faces of the sleeves on the feed rocker, the distance between the outer faces of the sleeves on the feed bar being less than the distance between the inner faces of the sleeves on the feed rocker, whereby the shaft may be adjusted endwise.

In testimony whereof, I afiix my signa ture. I

JAMES R, MOFFATT.

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