US2035508A - Feeding mechanism for sewing machines - Google Patents

Description

v 7 March 31, 1936. s u r L 2,035,508

FEEDING MECHANISM FOR .SEWING MACHINES Filed May 31, 1933 4 Sheets-Sheet l Q i I J a; $35? 23am k a w 61 m N i W I il o 4 W x v-i JV I! 7 M K fimkai WWBQ March 31, 1936. G. SAUER AL 2,035,508

FEEDING MECHANISM FOR SEWING MACHINES Filed May 51, 1933 4 Sheets-Sheet 2 5 6 W 6610 A v g-rwa/li b o March 31, 1936. G. SAUER ET AL FEEDING MECHANISM FOR SEWING MACHINES Filed May 31, 1935 4 Sheets-Sheet 3 March 1936- G. SAUER r-:r AL v 3 ,5

FEEDING MECHANISM FOR SEWING MACHINES Filed May 31, 1933 4 Sheets-Sheet 4 L film. Illllllllll lllLlLllHl VIIIIl/II'III Patented Mar. 31, 1936 UNITED STATES PATENT OFFICE 2,035,508 FEEDING MECHANISM FOR SEWING HINES MAC Illinois Application May 31, 1933, Serial No. 673,738

11 Claims. (01. 112-215) The invention relates to new and useful improvements in a feeding mechanism for sewing machines.

An object of the invention is to provide a feeding mechanism wherein the feed bar is reciprocated positively by a direct connection to an eccentric member, which connection includes devices for varying the movements imparted to the feed bar without varying the effective stroke of the eccentric member.

A further object of the invention is to provide a feeding mechanism of the above type wherein the feed rocker connected to the feed bar for moving the same endwise is oscillated by an eccentric strap-cooperating with an eccentric on an actuating shaft, which eccentric strap is, so constructed that the lateral movements of the strap impart the oscillations to the feed rocker.

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

In the drawings- Figure l is a view partly in plan and partly in horizontal section showing a portion of a sewing machine having the improved feeding mechanism embodied therein;

Fig. 2 is a sectional view on the line 2-2, of Fig. 1, also showing the lower portion of the standard, the needlebar, the presser bar and the presser foot;

Fig. 3 is a sectional view on the line 33 of Fig. 1;

Fig. 4 is a sectional view on the line 4-4 of pi I Fig. 5 is a diagrammatic view showing the control means as set for moving the feed-dog in one direction, and an adjustment thereof .in broken lines;

Fig. 6 is a diagrammatic view showing the control means set for a movement of the feed dog in the reverse direction, and also an adjustment thereof in broken lines;

Fig. '7 is a view similar to Fig. 1, but on a smaller scale and showing a modified arrangement for controlling the movements of the feed dog, and

Fig. 8 is a sectional view on the line 8-8 of Fig. 7.

Fig. 9 is a perspective view partly in section of a portion of the feeding mechanism, showing in particular the means for oscillating the feed rocker and imparting feeding movements to the feed bar.

The improved feeding means includes a feed dog mounted on a feed bar. The feed bar is positively raised and lowered by an eccentric member on an operating shaft. The feed bar is pivotally connected to a feed rocker. Mounted on the operating shaft is an eccentric. An eccentric strap cooperating therewith is pivotally connected to the feed rocker. This eccentric strap 5 is made in two sections, one of which telescopes within the other so that .an endwise movement of the section of the eccentric strap cooperating with the eccentric imparts no movement to the feed rocker. Pivoted to the section of the eccentric 10 strap which is connected to the feed rocker is a control link which may be positioned so that the lateral movements of the eccentric strap, as a whole, will cause the section of the eccentric strap;

connected to the feed rocker to move endwise. 16

Means is also provided whereby the control link may be shifted to different set positions for varying the extent of variation imparted to the feed rocker, or for reversing the direction of the feed without, in any way, modifying the movement of 20 the operating shaft and the portion of the eccentric strap cooperating therewith.

, Referring more in detail vto the drawings, the feeding mechanism is shown as applied to a sewing machine which is provided with a support- 25 ing bed I carrying a throat plate 2. Attached to the bed is a standard 3 carrying an overhanging arm supporting a needle head 4 in which a needle bar 5 reciprocates. The needle bar carries a needle 6. Cooperating with the needle beneath the 3 work support, as shown in the drawings, is arotary hook I.

The material is held on the supporting bed by a presser foot 8. It is fed across the supporting bed by a feed dog 9. The feed dog 9 is car- 35 ried by a feed bar I0 which is provided with a depending member I I. Beneath the supporting bed I is an operating-shaft l2. This operating shaft 12 terminates adjacent the feed bar. Eccentrically located in the shaft is .a crank pin I 3 0 which projects beyond the end of the shaft. The crank pin is held in place in the shaft by a set screw l4. The supporting bed is provided with a depending bracket lithrough which the operating shaft l2 extends and in the bracket is a 45 bushing IS. A link I! is connected to said crank pin and to a stud l8 carried by the depending member I I. As the shaft I2 rotates, the feed bar will be raised and lowered through this link connection. It is noted that the end of the shaft I2 carrying the crank pin is supported by this depending bracket so that the vibrations in the shaft incident to the raising and lowering of the feed bar are reduced to a minimum. The rotating hook I is carried by an auxiliary shaft I9. Attached to this. shaft is a gear 20 which meshes with a gear 2| on the operating shaft l2. The throat plate 2 is provided with feed slots 22, 22 through which sections of the feed dog 9 operate for feeding the fabric. The feed bar I0 is mounted for swinging movement on the rod 23 forming a part of a feed rocker 24. The feed rocker 24 is attached to a rod 25 mounted for oscillation in bearings 25, 26. Extending laterally from the feed rocker 24 is a pin 21. On the operating shaft i2 is an eccentric 28. An eccentric strap cooperates with this eccentric 28 and is connected to the pin 21. This eccentric strap consists of two separate members. The section 29 thereof carries a rod 30 which telescopes within the section 3| carrying a sleeve 32 engaging the pin 21. As the shaft l2 rotates, the eccentric will impart an endwise movement to the rod 30, but this endwise movement of the rod 30 is a free movement in the section 3| and does not produce any. oscillations in the feed rocker.

Attached to the outer end of the section 3| is a pin 33 to which a link 34 is connected. The link 34 at its other end is connected to a pin 35 attached to an arm 36. This arm 36 is fixed to a shaft 31 mounted in suitable bearings carried by the supporting bed I. At the outer end of the shaft 31 is an arm 33 to which a bar 39 is attached. This bar is provided with a cylindrical head portion 40 located in an opening 4| in a depending skirt 42 of the supporting bed. The rod is threaded as indicated at 43. Threaded on the rod is a disk 44 which extends up through a slot 45 in the supporting bed I. At the inner end of the bar 39 is an upstanding member 46 located in a slot 41 and having its upper face substantially flush with the upper face of the bed of the machine. The upper face of this member 46 is graduated and the bed is provided with a zero mark adapted to cooperate with the graduations on this member for indicating the length of the stitch. The disk 44 is knurled, and by turning the disk, the bar 39 can be shifted endwise. The shifting of the bar endwise will move the shaft 31 and shift the arm 36 to different set positions.

In Figures 7 and 8 of the drawings, there is shown a modified form of construction for manually shifting the parts which control the movements of the feed dog. For the shaft 31, there is substituted alonger shaft 31 which extends to the standard and into the same. An arm 38' is attached to the shaft 31 at the end thereof within the standard. Pivoted to the arm 38' is a rod made in two sections 39 and 39". These two sections have a threaded connection. The portion 39" extends through the standard and is provided with a knurled head 44' on its upper end. This knurled head contacts with the outer face of the standard. There is a collar 48 which is fixed to the section 39 of the rod, and this contacts with the inner face of the standard. The section 39" cannot move endwise, but is free to be rotated. When rotated in one direction, it will be threaded into the member 39 and thus the rod will be shortened. This will shift the arm 38' and bring about a change in the movement of the feed dog. When the knurled head is turned in the opposite direction, then the rod will be lengthened, and this will likewise shift the arm 38', but in the opposite direction, and thus produce a contrary change in the length of the feed stroke.

It is thought that the operation of the feeding mechanism, and particularly the means for moving the feed dog back and forth will be better understood from a brief description of the diagrammatic illustration in Figures 5 and 6. The

circle a represents the throw of the eccentric 23. The line b is one extreme movement of the eccentric strap in a lateral direction and the line b is the other extreme movement thereof. When the eccentric strap is in the position indicated at b, the link 34 will be in the position indicated at c, and when the eccentric strap is in the position indicated at b, then the link will be moved to the position indicated at c'. The line (1 indicates the position of the arm 36. When the link is in the position indicated at c, the point of connection between the link and the section 3| of the eccentric strap, will be at the point indicated at e, and whenthe link is shifted to the position indicated at c', then this point of connection will be at the point e. The lateral movement of the eccentric strap swings the link from the full line position 0 to the full line position 0, and the point of connection between this link and the section of the eccentric strap connected to the feed rocker will move from the point e to the point e. This movement is in part vertical, but it is also in part horizontal. The extent of the horizontal component of movement of this point of connection with the section 3| of the eccentric strap will be determined by the angular position of the arm 36 which is indicated by the line (1. When this arm is shifted to the position d, then the center of oscillation of the link will be shifted from the point 0 to the point 0'. This will shorten the horizontal component of movement of the pivotal connection between the link and the section of the eccentric strap connected to the feed rocker. When the section 3| of the eccentric strap is positioned on the full line indicated at b, the pivotal connection between said section and the feed bar will be at the point 1, and when the eccentric strap is in the position indicated by the line b, then this point of connection to the feed rocker will be at the point I. The pivotal connection between the feed rocker and the feed bar will shift from the point 9 to the point a, and this is the length of the feed stroke of the feed dog. Upon shifting the arm 36 from the full line position indicated at d to the broken line position indicated at 11', then the feed rocker will move only from the position indicated at h to the position indicated at h, and the length of the feed stroke will be greatly shortened. In Fig. 6, in full lines, the arm 36 has been shifted so as to position the link 34 at the full line position d". In this position of the link, the pivotal connection between the link and the section 3| of the eccentric strap will shift from the position I to the position 1', and this will reverse the direction of feed, as the feed rocker will move from the position m to the position m, and the feed member from the position 12 to the position 11. When the arm 36 is shifted to the broken line position d', then the length of the feed stroke in a reverse direction is from r to 1".

From the above it will be noted that the feed rocker is oscillated through the lateral movements of the eccentric strap and not through the longitudinal movements of the section of the eccentric strap which cooperates with the eccentric. The lateral movements of the eccentric strap impart a certain swinging movement to this control link 34 which causes a certain horizontal component of movement or endwise movement of the section of the eccentric strap which is pivoted to the feed rocker. The extent of this horizontal component of movement depends upon turning of the knurled disk and the endwise' movement of the control bar 39. v

It is obvious that the feeding mechanism described may be used in connection with any type of sewing machine, whether it produces lock stitches or chain stitches, and the stitching mechanism shown is purely for the purpose of illustrating the desired location of the feeding mechanism relative thereto.

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

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

1. In a sewing machine, afeed dog capable of longitudinal and vertical movement, an operating shaft, means actuated by said shaft for imparting vertical movement to the feed dog, a feed rocker which imparts longitudinal movementto the feed dog, an eccentric on the operating shaft, an arm pivoted to the feed rocker, means whereby said eccentric imparts swinging movements to said arm, and means whereby the swinging movement of said arm imparts endwise movement to said arm and an oscillating movement to the feed rocker.

2. A feeding mechanism for sewing machines comprising a feed dog, a feed bar, a. feed rocker to which said feed bar is connected, an operating shaft, means actuated by said shaft for raising and lowering the feed dog, an eccentric on said shaft, an eccentric strap cooperating with said eccentric and connected to said feed rocker, said eccentric strap including telescoping members having a free sliding connection one within the other, and means connected to the member attached to the feed rocker and operated by the lateral movements of the eccentric strap for imparting endwise movement to said member'for oscillating the feed rocker.

3. A feeding mechanism for sewing machines comprising a feed dog, a feed bar, a feed rocker to which said feed bar is connected, an operating shaft, means actuated by said shaft for raising and lowering the feed dog, an eccentric on said shaft, an eccentric strap cooperating with said eccentric and connected to said feed rocker, said eccentric strap including telescoping members one of which cooperates with the eccentric strap and the other of which is pivoted to the feed rocker, said telescoping members having a free sliding connection, a link pivotally attached to the outer end of the telescoping member connected to the feed rocker, and a support for said link disposed so that the lateral movements of the eccentric strap will cause said link to swing and impart endwise movements to the telescoping member attached to the feed rocker.

4. A feeding mechanism for sewing machines comprising a feed dog, a feed bar, a feed rocker to which said feed bar is connected, an operating shaft, means actuated by said shaft for raising and lowering the feed dog, an eccentric on said shaft, an eccentric strap cooperating with said eccentric and connected to said feed rocker, said eccentric strap including telescoping members one of which cooperates with the eccentric strap and the other of which is pivoted to the feed rocker, said telescoping members having a free sliding connection, 'a link pivotally attached to the outer end of the telescoping member connected to the feed rocker, a support for said link disposed so that the lateral movements of the eccentric strap will cause said link to swing and impart endwise movements to the telescoping member attached to the feed rocker, and means -direction of the feed.

5. A'iffidlng mechanism for sewing machines comprising a feed dog, a feed bar, a feed rocker to which said feed bar is connected, an operating shaft, means actuated by said shaft for raising and lowering the feed dog, an eccentric on said shaft, an eccentric strap cooperating with said eccentric and connected to said feed rocker, said eccentric strap including telescoping members one of which cooperates with the eccentric strap and the other of which is pivoted to the feed rocker, said telescoping members having a free sliding connection, a link pivotally attached to the outer end of the telescoping member connected to the feed rocker, a support for said link disposed so that the lateral movements of the eccentricstrap will cause said link to swing and impart endwise movements to the telescoping member attached to the feed rocker, said support for the-link including an arm,- a shaft carrying said arm, and manual means for shifting the arm. from one set position to another. 6. A feeding mechanism for sewing machines comprising a feed dog, a feed bar, a feed rocker to which said feed bar is connected an operating shaft, meansactuated by said shaft for raising and lowering the feed dog, an eccentric on said shaft, an eccentric strap cooperating with said eccentric and connected to said feed rocker, said eccentric strap including telescoping'members one of which cooperates with the eccentric strap and the other of which is pivoted to the feed rocker, said telescoping members having a free sliding connection, a link pivotally attached to the outer end of the telescoping memberconnected to the feed rocker, a support for said link disposed so that the lateral movements of the eccentric strap will cause said linkto swing and impart endwise movements to the telescoping member attached to the feed rocker, said support for the link including an arm, a shaft carrying said arm, a second arm attached to said shaft, a bar pivoted to said second arm and slidingly supported for endwise movement, a knurled disk having threaded connection with said bar, and means cooperating therewith whereby the turning of the disk will shift the bar endwise and shift the arm supporting the link to a different set angular position.

'7. A feeding mechanism for sewing machines including a supporting bed, a feed bar located beneath the bed, a feed dog carried thereby and projecting through slots in the bed for feeding the fabric, a feed rocker to which said feed bar is pivotally attached, an operating shaft beneath the bed and having its end terminating adjacent the feed bar, a bearing carried by the supporting bed in which the end of the shaft is journaled, a crank pin mounted in the end of the shaft, a depending member carried by the feed bar, a link connecting the crank pin to the lower end of said depending member for raising and lowering the feed dog, means operated by said shaft for oscillating the feed rocker, said last-named means including an eccentric on the operating shaft, an eccentric strap cooperating therewith and pivotally connected to said feed rocker, said strap being formed of two telescoping sections having free sliding connection, a link'pivotally connected to the section of the eccentric strap which is attached to the feed rocker, and a support for said link positioned relative to the eccentric strap so that the oscillations of the link, due to the lateral movements of the eccentric strap will impart endwise movements to the sections of the eccentric strap connected to the feed rocker.

8. A feeding mechanism for sewing machines comprising a feed dog, a feed bar, a feed rocker to which said feed bar is connected, an operating shaft, means actuated by said shaft for raising and lowering the feed dog, an eccentric on said shaft, an arm pivoted to the feed rocker, means whereby the eccentric imparts swinging movements to the arm, means whereby the swinging movements of the arm imparts an endwise movement to said arm and an oscillating movement to the feed rocker, said last-named means including a pivoted swinging member, the position of which determines the extent of oscillation imparted to the feed rocker, a shaft, an arm carried thereby on which said member is pivotally supported, a second arm carried by said shaft, a rod pivoted to said second arm, said rod including sections having a threaded connection one of which is pivoted to the arm and the other of which is mounted for rotation, but held from endwise movement so that .the turning of the rod section will lengthen or shorten the rod and vary the set position of said shaft.

9. In a sewing machine of a feed dog capable of longitudinal and vertical movement, an operating shaft, means actuated by said shaft for imparting vertical movements to the feed dog, means connected to the feed dog for imparting having its end terminating adjacent the feed bar, a bearing carried by the supporting bed in which the end of the shaft is journalled, an eccentric on the operating shaft, an arm pivoted to the feed rocker, means whereby said eccentric imparts swinging movement to said arm, means whereby the swinging movements of the arm are caused to impart a rocking movement to the feed rocker and a feeding movement to the feed dog, a crank pin mounted on the end of the shaft, a

depending member carried by the feed bar and a link connecting the crank pin to the lower end of the depending member for raising and lowering the feed dog.

11. In a sewing machine, an actuating shaft, a. feeding mechanism including a feed bar, a feed dog carried by said feed bar, means for raising and lowering said feed bar, mechanism for moving said feed bar back and forth comprising an eccentric on said actuating shaft, a member having connection with said feed bar for moving it back and forth, said member being movable pivotally relative thereto, devices cooperating with said eccentric for imparting oscillations to said member on said pivot, and devices for translating the oscillating movements of said member into back and forth movements of said member and said feed bar.

GEORGE SAUER. CLARENCE C. SMITH.

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