US1543946A - Feeding mechanism for sewing machines - Google Patents

Description

June 30, 1925. 1,543,946

J. R. MOFFATT FEEDING MECHANISM FOR SEWING MACHINES Filed April 19 1921 5 Sheets-Sheet 1 119 74 20 a/WQZ gwvenfqt WQW imam 30, 1925.

1,543,946 J. R. MOFFATT FEEDING MECHANISM FOR SEWING MACHINES Filed April 19, 1921 3 Sheets-Sheet 2 June 30, 1925 1,543,946

J. R. MOFFATT FEEDING MECHANISM FOR SEWING MACHINES Filed April 19, 1921 3 Sheets-Shet 3 Jvwm 1 I of Patented June 30, 1925.

UNITED STATES PATENT OFFICE.

JAMES R. MOFFATT, OF CHICAGO, ILLINOIS, ASSIGNOR TO UNION SPECIAL MACHINE COMPANY, OF CHICAGO, ILLINOIS,

A CORPORATION OF ILLINOIS.

FEEDING MECHANISM FOR SEWING MACHINES.

Application filed April 19, 1921. Serial No. 462,572.

To all whom z't may concern:

Be it known that I, JAMES R. citizen of the United States, residing at Chicago, in the county of Cook, 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. a

This 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 and MorrA'r'r, a

operating through slots in the work support disconnecting the actuating for engaging and feeding the material, and wherein the feed dog is carried by a feed bar attached to a feed rocker which is oscillated for imparting the feeding movements to the feed dog.

An object of the invention is to provide a feeding mechanism of the above character wherein the feed rocker is oscillated by an arm movably or adjustably connected thereto, which connection permits the feed rockers' to be shifted for varying the working position of the fabric engaging sections of the feed dog in their respective slots.

A further object of the invention is to provide a feeding mechanism of the above character wherein the feed rocker may be shifted for centering the feed dog without arm from its operating means.

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 improvements embodied thereinand with a part of the work support broken away to show the feed dog supporting means beneath said work support;

Fig. 2 is a view partly in section and partly in elevation from the left-hand end of the machine;

Fig. 3 is a view partly in section and partly in rear elevation of the same;

Fig. 4 is a view partly in section and partly in end elevation of the parts beneath the work support;

Fig. 5 is a perspective view showing the parts separated. which operate the arm for moving the feed dog hack and forth;

- and 7. The feed dog indicated at Fig. 6 is a section on the line 66 of Fig.

Fig. 7 is a perspective View of the feed rocker, and

Fig. 8 is a perspective View of the feed bar and feed dog carried thereb The invention is directed broadly to a feeding mechanism of the type wherein the feed dog is mounted beneath the work support and is provided with fabric engaging sections operating through slots in the work the feed bar so that the fabric located centrally of the slots in which thev work. The feed rocker is oscillated by ah arm which is formed integral with a short stud which in turn is clamped in a split sleeve formed as a part of the feed rocker.

- This arm is connected by means of a link "to an adjustable crank pin on the end of the main shaft. By loosening the connection of the arm to the feed rocker, said feed rocker may be moved forwardly or rearwardly and the working position of the feed dog shifted, and thus the working stroke of the feed dog centered relative to the longitudinal length of the slots in the throat plate forming a part of the work support, and this shifting of the feed rocker to center the feed dog is accomplished without disconnecting the arm from its actuating means.

Referring more in detail to the drawings, my improved feeding mechanism is shown as applied to a sewing machine having a supporting bed 1 carrying a work support 2 to which is attached a throat plate 3. This throat plate is provided with needle openings 4, 4 and with three feed slots 5, 6 8 is pro vided with fabric engagingsections 9, 10 and 11 which work respectively in the slots 5, 6 and 7. The feed dog 8 is carried by a food bar 19 which is provided with a laterally proicctiug arm 13 and spaced sleeves 14, 14. The feed bar is raised and lowered by and said collars bear against the outer faces lugs 21, 21.

is a shaft 25.

of the sleeves 19, 19. The feed rocker is sooured to the shaft 20 by set screws 24. The distance between the outer faces of the sleeves 18, 18 is slightly less than the distance between the inner faces of the bear-ing Mounted in the sleeves 19, 19

through the sleeves 14, 14 which are secured to the shaft by means of set screws 26: The

shaft is held from endwise movement in the sleeves 19, 19 by means of collars 27 27 which are'secured to the shaft 25 by set screws 28, 28. The distance between the inner faces of the sleeve bearings 19, 19 is slightly greater than the distance between the outer faces of the sleeves 14. By shifting the shaft 25 or the shaft 20 endwise, the

feed bar may be moved bodily laterally, and thus the fabric engaging sections of the feed dog centered relatlve to the transverse width of the feed slots. This features, per se, forms no part of the present invention, but is'shown, described and claimed in my copending application, Serial No. 462,571 filed of even date herewith.

The feed rocker isoscillated for impart-' ing feeding movements to the feed dog by means of an arm 29. This arm'is provided with a stud 30 which is preferably formed integral with the arm. The stud 30 is adapted to enter a split sleeve 31 preferably formed integral with the feed rocker 17.-

Said split sleeve is clamped on to the stud by means of screws 32, 32. This serves as a means for rigidly securing the arm 29 to the feed rocker. By loosening the screws 32, the feed rocker may be shifted forwardly or rearwardly, the stud 30 turning in said sleeve 31.

On the end of the main shaft 16 there is a disk 33 which is provided with a diametrically arranged .T-slot 34. Located in this T-slot is a block 35 which carries the crank pin 36. Said block may be shifted in the slot by means of an adjusting screw 37. On the crank pin is placed a sleeve 38 which is free to'oscillate on' said crank pin. A link 39 is provided with a cylindrical opening 40 adapted to receive the sleeve 38 and clamping screw 41 serves to cause the link to firmly gri the sleeve. vided with spaced sections 42, 42 between which the end of the arm 29 extends and a pivot pin 43 carried by the spaced sections This shaft also extends Said link 39 is pro- 42 of the link serve as a pivotal connection between the link 39 and the arm 29.

the main shaft rotates, the crank pin 36tl1rouglflthe link 39 will oscillate the arm 29, and'this in turn will oscillate the feed rocker 17. The oscillating movements of the feed" rocker through the feed bar are imparted tothe feed dog and thus the feed dog is given its feeding movements. It will readily be seen that when the connection between the. arm 29 and the feed rocker is loosened. the feed rocker may be shifted forwardly or rearwardly, which will shift thesfeed dog either forwardly or rearwardlv to anew working position. Thus it is that the working positionof the fabric engaging sections of the feed dog maybe centered relative to thelength of the feed slots in which they operate.

Then, again, by loosening the collars 22, v

22, the shaft '20 may be moved endwise which will bodily shiftthe feed rocker for lateral- 1 1y centering the feed dog in the feed Slots.

as has been described abdve. The stud 30 may be readily shifted endwise in the sleeve 31 so va sto accommodate itself to the new position ofthe feed rocker, and thus the arm 29 can remain in proper sition so as to actuate thefeed rocker wit out an binding of the parts and yet permit this b0 ily shifting ofthe feed rocker for centering the feed dog. s

It is obvious that minor changes in details of construction'may be made without "doe parting'from the spirit of the invention as set forth in the appended claims.

Having thus described the invention, what I claim as new and desire to' secure by Letters-Patent, is

1. In a sewing machine, the combination of a work support having feed slots and a feeding 1 mechanism including a feed dog fhavingfabric engaging sections working in said slots, a feed bar to which said feed dog is attached, means for raising and lowering said feed bar, a feed rocker to which said.

baris connected, an arm, means for connectlngsaidarm .to the feed rocker, and means .for oscillating the arm forimparting feed movements to the feed dog, said connecting means for the arm and rocker being such as to permit the working position of the feed rocker to be 'shifted forwardly or rearwardly for centering the feed, dog-length wise of the feed slots the length of the stroke remaining the same.

2. ,In a sewing machine, the combination of a work'support having feed slots, and a feeding mechanism including a feed dog having'fabric engagingsect-ions working in said slots, 'a feed bar to which said feed dogis attached, means for raising and lowering said feed bar, afeed rocker to which said feed bar is connected, an arm, said arm having a projecting stud, a split sleeve carried the feed rocker in which said stud is iadjustably held whereby the feed rocker may be shifted forwardly or -rearw'a'r'dly, and

meansfor oscillat-in the arm for imparting feed movements to t e feed dog.

7 3. Ina sewing machine, the combination of a work support having feed slots, a feedmechanism including a feed dog having in ffafiric engaging sections working in said main shaft, and a link connecting the crank to the free end of the arm for oscillating said arm for imparting back andforth movements to the feed dog.

4. In a sewing machine, the combination of a work support having feed slots, a feeding mechanism including a feed dog having fabric engaging sections working in said slots, a-feed bar to which said feed dog is attached, means for raising and lowering said feed bar, a feed rocker to which said bar is connected, an arm, said arm having a projecting stud, a split sleeve carried by the feed rocker in which said stud is adjustably held whereby the feed rocker may be shifted forwardly or rearwardly through the shifting of the connection of the arm to the feed rocker, a main shaft, a crank on the main shaft, a link connecting the crank to the free end of the arm for oscillating saidv arm for imparting back and forth movements to the feed do a shaft on which said feed rocker is rigi 1y mounted, means whereby said shaft, may be shifted endwise for shifting the feed dog laterally to position the fabric engaging sections thereof centrally of the feed slots, the adjustable connection between the stud and the split sleeve permitting said sleeve and stud to have an endwise relative movement whereby said feed rocker may be shifted laterally without causing the connection of the arm to the operating mechanism therefor to cram or bind.

In testimony whereof, I a x my signature.

JAMES R. MOFFATT.

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