US2228718A - Stitch regulator and reversing mechanism for sewing machines - Google Patents

Description

Jan. 14, 1941.

BEST

STITCH REGULATOR AND REVERSING MECHANISM FOR SEWING MACHINES Filed May 15, 1959 FQZ 5 Sheets-Sheet l Jan. 14, 1941. C, s BES-|- 2,228,718

STITCH REGULATOR AND REVERSING MECHANISM FOR SEWING MACHINES Filed May 15, 1939 5 Shegts-Sheet 2 Jan. 14, 1941. C, s, BEST 2,228,718

STITCH REGULATOR AND REVERSING MECHANISM FOR SEWING MACHINES Filed May 15, 1939 3 Sheets-Sheet 3 f7zf7z for Terence 5. es

Patented Jan. 14, 1941 4MT1-:1yr OFFICE STITCH REGULATOR. AND EEVERSING MECHANISM FOB SEWING MACHINES Clarence S. Belt, Belvidere, lll., assigner to Natioml' Sewing Machine Company, Belvidere,

lll., a corporation of Illinois Application May 15, 1933, Serial No. 273,596

4Claims.

This invention relates to stitch regulator and reversing mechanism for sewing machines whereby the length of the stitches may be regulated and the direction of movement of the feed may be controlled. 1

'I'he main object of my invention is to provide stitch regulator and reversing mechanism which may be controlled by the operator by manipulation of a single element, preferably located on l0 the bed of the sewing head, adjacent to and forwardly of the upright standard, in a position most accessible to the right hand of the user.

Another object of the invention is to provide a feed-regulating lever which is accurate and reliable in use and provided with indicating means enabling the operator to obtain the desired feed adjustment.

Another object is to provide a feed regulating lever which is directly connected with cam means located beneath the bed plate of the sewing head,

the adjusted position of said cam means controlling both the direction and extent of movement of the feed dog on which the work rests.

In the drawings:

Fig. 1 is a front elevation of a sewing machine embodying my invention.

Fig. 2 is a horizontal sectional view, taken in the plane of the line 2-2 of F18. 1.

Figs. 3 and 4 are transverse vertical sectional views, on an enlarged scale, taken in the planes of the lines 3-3 and 4-4, respectively, of Fig. 1.

Fig. 5 is a transverse vertical sectional viellv.

showing some of the parts shown in Fig. 4. but in different positions, taken in the plane of the line 5--5 of Fig. 1.

Fig. 6 is a bottom plan view of the machine. Fig. 7 is a vertical sectional view, taken in the plane of the line 1-1 of Fig. 8.

Fig. 8 is a transverse vertical sectional view, taken in the plane of the line 3-3 of Fig. 1,

showing on an enlarged scale the feed regulating lever and adjacent parts.

In that embodiment of the invention shown in the drawings. the bed plate of the sewing head is indicated at I3, four legs at Il. the upright standard at I2 and overhanging arm at I3. A motor I4 drives the fly wheel l5 for actuating the stitch forming mechanism. which is not described herein in detail because the invention is directed to means for controlling the direction and extent of movement of the feed dos il movably mounted in the bed plate il. A presser foot is indicated at I1 and the work at i3.

The manually operable adjusting means whereby the operator controls the length of the stitches and direction of movement of the work is shown .in Figs. 1, 2, 7 and 8. Said means comprises a plate I8 cut -awayat 20. secured to the bed plate I8 by screws 2l. The part 22 is curved longitudinally as shown and is marked with 5 stitch-length indicating means.- The part 23, partly underlying the plate I8, is a strip of substantially V-form between flat ends, but the'center or bottom of the V is flat as indicated at 24 in Figs. 'I and 8, the bed plate I0 being cut l0 away beneath the slot 20 and member 23.

A feed control lever 25 extends through the slot 20. At its upper end it is provided with a pointer 28 which projects forwardly above the scale 22, land a screw threaded ear 21 in which l5 is mounted an adjusting screw 28. A collar 28 on the screw 28 limits its upward movement relatively to the ear 21 of the lever 25. The lower lend of said lever 25 is pivotally mounted on a pin 38 which extends through said lever end and is 20 iixed in the forward right hand leg Il.

When the screw 28 has been screwed downwardly as shown in Fig. 8 and in full lines in Fig. 7, the bottom of the screw touches lightly the flat part 24 of -the V-member 23, and the 25 possible movement of the screw, longitudinally of said member 23, is limited to the length of said flat part 24, and consequently only slight pivotal movement can be transmitted to the feed control lever 25. When the screw has been 30 screwed upwardly, the lower end of the screw contacts one or the other of the side walls of the V-portion of the member 23, as shown in dotted lines in Fig. 7, and movement of the lever 25 by manually grasping the head vof the screw 35 23 imparts increased pivotal movement to the lever 25, for the purposes to be described.

The feed control lever 25 has a pin 3l projecting from it rearwardly and horizontally, slightly beneath the bed plate l0, into engage- 40 ment with a sleeve 32, diagonally slotted at 33, said sleeve being fixed on acrank shaft 34, as shown in Figs. 1, 6, 'l and 8. The shaft 34 is rotatably mounted in bearings 35 and 36 fixed on the lower surface of the bed plate I3.- While 45 the shaft 34 is rotatably mounted in said bearings, it has limited rotative movement only, in opposite directions, imparted by manipulation of the lever 25 in the slot 20, and resultant rotative movement of the shaft 34 due to the engagement 50 of the pin 3| in the slotted sleeve 32` on said shaft.-

The shaft 34 has fixed to that end adjacent the bearing. a` crank cheek 31. the latterbeing pivotally connected by a crank pin 33 to a crank 55 cheek 33 nxed to a pin 4I. on which are pivotally mounted the arms 4i formed on the upper end of a link 42. The lower end of said link 42, in the form of a sleeve 43, is connected by a pivot pin 44 to a bell crank lever comprising a bifurcated arm 45 integrally formed on a rock shaft 44 having ends 41 mounted at one end in a bearing 43 and at the other end in the forward left hand leg Il, at 43, the other arm of the bell crank lever being indicated at Il.

As best shown in Figs. 1 and 3, the lever 5l extends upwardly from the rock shaft' 43 substantially at right angles to the arm 45 (Figs. 3, 4 and 5). Said lever 5l is plvotally connected at 5| to a feed bar 52 which extends transversely under the bed plate Il beneath-the feed dog Il. Said feed dog I3 is fixedly mounted on the bar 52 by depending ears 53 as indicated at 54.

The rearward end 55 of the bar 52 is pivotally connected at 53 to a lever 51, plvotally connected at 53 to a lever 55 integral with a rock shaft Il having ends 6I supported in a bearing 42 and in the rearward left hand leg Il at 33. 'I'he lever 53 is plvotally connected at 54 to a bifurcated arm on the sleeve 65 eccentrically mounted at I5 on the rotatable shaft 31 mounted in the bearings 33 and 63 (Figs. 3 and 6).

Also eccentrically mounted on said shaft 61.

-as shown at 1l, is the eye end 1l of a curved arm 12, plvotally' mounted at 13 (Fig. 1) on the pin 4l, between the sleeve members 4| of the link 42.

Within the housing 14 formed on the bottom of the bed plate lll are conventional gears 15, 16, driven by a gear 11 operatively connected to the motor shaft. The gear 15 drives the shaft $1 and the gear 16 drives the shaft 18 which operates the stitch forming means within the housing 19.

'I'he operation of the parts described is as follows: The4 operator adjusts the screw 23 according to the size of stitch desired, raising it relatively to the ear 21 of the feed control lever 25 if a long stitch is desired, and lowering it to obtain a short stitch. The screw is adjusted after the position of the pointer 26 has been selected, and contact of the lower end of the screw with the member 23 determines the position of the lever 25 at either side of the center of the slot 25,

will engage the slot 33 in the sleeve 32, thereby rotating the shaft 34 to predetermined position. 'I'his results in fixing the, crank 31 in one of its possible positions, as in Fig. 4, which position it retains until the lever 25 is moved, either to the opposite side of the slot 2li to reverse the direction of movement of the feed dog I6, as in Fig. 5, or by adjusting the screw 23 to change the length of the arc in which the lever 25 can travel, whereby therstitch length is controlled.

The rotation of the shaft 34 results in pivotal movement of the crank cheek 39, bodily movement of the pin 4l, pivotal movement of the link 42, and pivotal movement of the bell crank lever arms 45-50 about the axis of the rock shaft 46, the lever arm 53 moving the feed bar 52 to one of its two positions, for forward or reverse movement of the feed dog Ii. By reason of its pivotal con- -nection with the pin 40, the curved arm 12 on the shaft 51 is also moved by adjusting the shaft 34.

When the sewing mechanism is actuated, the rotation of the shaft 61 eects the feed dog lifting operation, intermittently, by means of the eccentric 43, sleeve 65, levers 53,51, and link ll on one end of dog I3. The eccentric 14, curved arm 1|-12-13, pin 4l, link 42, and bell crank lever 45-5l transmit reciprocating movement to .the bar 52 and dog Il transversely of the bed 5 plate il.

Changes may be made in details of construction without departing from the scope of my invention.

I claim:

1. Stitch regulating and reversing mechanism for sewing machines comprising a slotted bed plate, a feed dog transversely movable in the bed plate, an upright standard and overhanging arm, a feed lever extendingthrough said slotted bed 15 plate forwardly of the upright standard, the feed lever being plvotally mounted on a fixed support beneath the bed plate, a horizontally disposed stitch length indicating scale o'n the bed plate forwardly of the lever, a. flat bottomed V-shaped 20 member in the bed plate rearwardly of the feed lever, an,adjusting screw mounted on the lever for contact with the V-shaped member, a pointer on the lever adjacent said scale, and operative connections between the feed lever and the feed 25 dog for moving the dog to predetermined position.

2. In stitch regulating'and reversing mechanism for sewing machines, a bed plate, a horizontally disposed slotted plate mounted on the bed plate, said slotted plate having a stitch 30 length indicating scale on one side of the slot l and a. substantially V-shaped member on the other. side of the slot, a feed lever extending through the slot, said lever having a pointer on the side adjacent said scale and adjustable means 35 on the other side for contact with said V-shaped member.

3. In stitch regulating and reversing mechanism for sewing machines, a bed plate, a horizontally disposed slotted plate 'mountedv on the 40` bed plate, said slotted plate having a stitch length indicating scale on one side of the slot and a substantially V-shaped member on the other side of the slot, a feed lever extending through the slot, said lever having a pointer on th'e side adjacent 45 said scale and adjustable means on the other side for contact with said V-shaped member, said stitch length indicating scale being convex on its upper surface and said pointer overlying said scale in close proximity thereto throughout the 50 movement of said feed lever.

4. Stitch regulating and reversing mechanism for sewing machines comprising a bed'plate, a feed dog mounted in the plate, an upright standard, the bed plate being slotted longitudinally forwardly of the standard, a vertically disposed feed control lever plvotally mounted beneath the bed plate, extending through said slot and operable above the plate by movement longitudinally of the bed plate, a cam shaft rotatably mounted 60 beneath the bed plate and parallel to the vertical plane in which the feed control lever moves, a

- the bed plate controlling the position of the cam shaft and thereby determining the direction of movement and length of movement of the-feed dog.

CLARENCE s. BEST. 7 5

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