US1341388A - Feed mechanism for sewing-machines - Google Patents

Description

A. 0. SMITH.

FEED MECHANISM FOR SEWING MACHINES. APPLICATION men :uur 30', 1918.

2 SHEETS-SHEET l- A. D. SMITH.

FEED MECHANISM FOR SEWING MACHINES.

APPLICATION FILED JULY 30,1918.

1,341,38 Patented Ma 25,1920.

2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

ALBERT 1). SMITH, OF DETROIT, MICHIGAN.

" l' FEED MECHANISM FOR SEWING-MACHINES.

Application filed July 30, 1918.

1 b all whom it may concern:

Be it known that I, ALBERT D. SMITH, a citizen of the United States, residing at Detroit, in the county of Wayne and State of Michigan, have invented certain new and useful Improvements in Feed Mechanism for Sewing-Machines, of which the following is a specification.

This invention, pertaining to feed mech anism for sewing machines, has more particular reference to the provision of means for varying at will the length of the stitch and for reversing the direction of sewing while the machine is in operation.

In the use of sewing machines, especially in commercial sewing in factories and tailoring establishments, it is very desirable to be able to quickly varythe length of stitches and also to reverse the direction of feed. With sewing machines now in general use the length of the stitch may be varied by turning an adjusting screw; and in order to reverse the direction of feeding as is very desirable for the purpose of locking the stitches by sewing back and forth over seams without turning the goods around, the operator must raise the presser bar with one hand and with the other feed the goods backwardly a sufficient distance to lock the stitches, then lower the presser bar and continue forward sewing. This operation, however, requires expert manipulation, otherwise the needle is very apt to be broken. I

The primary object of the present invention is to overcome these difficulties by the provision of an improved means for regulating the length of stitch and for reversing the direction of the feed, the salient feature of the improvement being that the stitch regulation and feed reversal may be instantaneously effected by simply actuating a control member which is freely movable back and forth to instantly produce the desired feed movement. Thus, in commercial sewing with my improvement much time is saved and breakage eliminated, and any length of stitch within a wide variation or reversal of the feed is instantly obtainable.

Another object is to provide a simple and practical mechanism ofthe character mentioned, which shall consist of but few parts and shall include a manually operable control member having cooperating indicia designating the various changes effected by shifting the position of the control member.

Specification of Letters Patent.

Patented May 25, 1920.

Serial No. 247,427.

Other objects and attendant advantages will be appreciated as the invention becomes better understood by reference to the following description when considered in con nection with the accompanying drawings,

in whichshown are those of the feed mechanism.

My invention contemplates, generally speaking, the provision of an improved means for instantly regulating at the will of an operator the length of the stitch and the direction of feed, and is not, therefore, limited to the particular construction of the feed mechanism per 86. The feed mechanism taken as an example in illustrating my improvement is of a conventional fourmotion type. Referring to the drawings, the usual driving shaft 6 is ournaled in the horizontal arm 7 of a sewing machine head and is adapted to be driven by suitable means such as a belt pulley 8. This feed mechanism includes separate motion-trains operated by the shaft 6 and passing downwardly through the upright column 9 of the head for actuating a pair of rock shafts 11 and 12 mounted below the work plate 13.

Arms 14 and 15 secured respectively to the rock shafts 11 and 12 are connected to the extremities of a feed bar or member designated generally by character 16, which has a suitable roughened toothed surface adapted to be projected through the throat plate for feeding the material either from or toward the front of the machine. The rock shaft 11 is oscillated to elevate and lower the feed member and the rock shaft 12 advances and retracts the feed mechanism in synchronism with the elevating and lowering movements, these rock shafts being respectively operated from the driving shaft 6 through the agency of the separate motiontrains or connections mentioned above. The connections for imparting this motion consist of an eccentric 17 fixed to the shaft 6 and connected by a link 18 to a crank arm 19 fixed to the rock shaft at the rear of the crank 14. The eccentric 17 simply lowers and elevates the feed member when the driving shaft is re volved. Another eccentric cam 21 of suitable shape secured to the driving shaft 6 opcrates between the yoked end 22 of a link 23 connected to the crank arm 24 which is fixed to the rock shaft 12. The eccentric cam 21 will oscillate the upper end of the link 23 forwardly and backwardly, and other means operating on the link intermediate its ends produces a raising and lowering movement as a result of the forward and backward oscillation of the link. This means consists of a rocker plate or member designated by character 25 pivotally mounted at 26 on the column 9 adjacent to one side of the link 23 and shaped to provide a guideway 27. A follower in the form of a roller 28 carried by the link 23 is disposed between the guide surfaces on the rocker plate and adapted to be moved back and forth along said surfaces by the action of the eccentric cam 21. By rocking the member 25 about its pivotal mounting 26, the inclination of the guide surfaces can be varied to produce a greater or less vertical movement of the roller 28, and consequently of the link 23, when the link is operated by its eccentric cam. Such operation of the link 23 will obviously oscillate the crank 15 in a manner to advance and retract the feed member 16 in feed movements of different lengths.

Means is 'now provided for regulating the position of the rocker member 25 to not only change the inclination of its guideway to vary the length of stitches but also to swing the rocker member to such position as to reverse the direction of the feed movement. This means consists preferably of a regulating member 29 pivotally connected at 31 to a depending arm of the rocker member 25 and extending forwardly through an aperture 32 in the front wall of the column 9 and constituting at its forward end a handle which may be pushed in and out to oscillate the member 25. A simple means is provided for holding the regulating member 29 in any adjusted position and permitting the member to be easily shifted at will and consists in this case of a spring 33 which constantly urges the regulating mem ber 29 sidewise into frictional contact with one wall of the aperture 32 in the upright column; The spring 33 is mounted on a pin 34: carried by a lug 35 projecting forwardly from the column and is held in positionby an abutment 36 also mounted on the set screw 3a and secured thereby to the lug 35. The upper end of the spring 33 serves as a pointer 37 overlying the top surface of the regulating member 29, which surface is provided with suitable indicia representing 1,341,:sse

the different lengths of stitches and the direction of feed produced by adjustment of the member 29. As the parts are shown in full lines in Fig. 3, the usual feed stroke from the front of the machine to the rear has just been completed, that is, the feed member, held in elevated position, has been fully advanced toward the rear of the machine. When now the driving shaft 6 is revolved in a clockwise direction, viewing Fig. 3, the eccentric 17 will lower the feed bar and the eccentric cam 21 will swing the upper end of the link 23 rearwardly, causing the roller 28 to follow the upward inclination of the guideway 27 and be raised thereby. This raising movement of the link 23 retracts the feed member while the latter is in its lowered position. During the neXt half cycle of the driving shaft the feed member will be elevated and advanced in a feed movement as is obvious, thus concluding a single four-motion feed movement. It will be readily understood that by pulling the regulating member 29 forwardly a slight distance, the angle of the guideway 27 will be lessened, thus diminishing the extent of the advance movement of the feed -member until, when the guideway is horizontal, practically no feed movement will be produced. Upon continuing to pull the member 29 forward the guideway 27 will be tilted in the opposite direction, as indicated in Fig. 3 by the dotted line position of the member 29 and parts connected thereto. This will produce a reversal of the feed movement so that when the feed member 16 is elevated it will be moved toward the front of the machine in a retracting direction, but in a feed movement, thus feeding the material in a reverse direction, that is, toward the front of the machine. Such reversal of the feed movement can be instantaneously effected by simply sliding the regulating member 29 outwardly and inwardly, past a central position, and it will 1 1 be manifest that while the machine is in operation the change is instantaneously effected. It is now desired to effect this reversal of feed and to instantly return to the same length of forward stitch. F or this purpose, I have equipped the regulating member 29 with a stop 38 adjustable in a slot-way 39 in the handle. The stop 38 is adapted to abut against the face of the head to limit the inward movement of the regulating member. This construction allows the regulating member to be pulled forwardly to instantly reverse the direction of sewing and then to be pushed back to the position limited by the stop 38. In other words, the operator reverses the direction of sewing and then returns the feed mechanism to the former working condition and same length of stitch without detracting attention from the sewing. t I

It is believed that the foregoing conveys a clear understanding of my improvements and it should be understood that while I have illustrated but one practical embodiment thereof, various changes might be made in the construction and arrangement without departing from the spirit and scope of the invention as expressed in the appended claims, in which- I claim:

1. In a sewing machine, the combination of a head having an upright column, a driving shaft passing through the upper end of said column, a feed bar, motion trains passing through the vertical column and operable between said shaft and said feed bar for imparting feed motion to the latter, means for regulating the feed motion comprising a rocker member having a guideway, a guide on one of said motion trains adapted to be actuated by aid guideway to vary the length of the feed movement and effect reversal thereof, and a regulating member slidable horizontally through an opening in the front wall of said vertical column and pivotally connected at its inner end to said rocker member and shaped at its outer end to provide a suitable hand grasp by means of which the regulating member may be positioned in or drawn out at will to quickly regulate the length and direction of feed movement.

2. In a sewing machine, the combination of a head having an upright column, a driving shaft passing through the upper end of said column, a feed bar, motion trains passing through the vertical column and oper able between said shaft and said feed bar for imparting feed motion to the latter, means for regulating the feed motion comprising a rocker member having a guideway, a guide on one of said motion trains adapted to be actuated by said. guideway to vary the length of the feed movement and effect reversal thereof, a regulating mem ber slidable horizontally through an opening in the front wall of said vertical column and pivotally connected at its inner; end to said rocker member and shaped at its outer end to provide a suitable hand grasp by means of which the regulating member may be positioned in or drawn out at will to quickly regulate the length and direction of feed movement, and a spring constantly urging the regulating member against a wall of said vertical column for imposing such yielding resistance to movement of said member as will prevent displacement thereof from any set position,

yet allow quick shifting of said member to any new position.

3. In a sewing machine, the combination of a head having an upright column, a driving shaft passing through the upper end of said column, a feed bar, motion trains passing through the vertical column and operable between said shaft and said feed bar for imparting feed motion to the latter, means for regulating the feed motion comprising a rocker member having a guideway, a guide on one of said motion trains adapted to be actuated by said guideway to vary the length of the feed movement and effect reversal thereof, a regulating member slidable horizontally through an opening in the front wall of said vertical column and pivotally connected at its inner end to said rocker member and shaped at its outer end to provide a suitable hand grasp by means of which the regulating member may be positioned in or drawn out at will to quickly regulate the length and direction of feed movement, and indicia on the regulating member inclicating the effect produced by the said member in any of its shifted positions.

4. In a sewing machine, the combintion of ahead having an upright column, a driving shaft passing through the upper end of said column, a feed bar, motion trains passing through the vertical column and operable between said shaft and said feed bar for imparting feed motion to the latter, means for regulating the feed motion comprising a rocker member having a guideway, a guide on one of said motion trains adapted to be actuated by said guideway to vary the length of the feed movement and effect reversal thereof, a regulating member slidable horizontally through an opening in the front wall of said vertical column and pivotally connected at its inner end to said rocker member and shaped at its outer end to provide a suitable hand grasp by means of which the regulating member may be positioned in or drawn out at will to quickly regulate the length and direction of feed movement, and a stop adjustable in a horizontal plane upon and with respect to the regulating member and adapted for contact against a part station-' ary with respect to the vertical column for limiting movement of the regulating member in one direction to any of a plurality of positions determined by the setting of said stop.

ALBERT D. SMITH.

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