US2454710A - Stop mechanism for sewing machines - Google Patents

Description

@v. 23, 1948. 1 w, MYERS 2,454,710

STOP MECHANISM FOR SEWING MACHINES Filed June 12, 1945 2 Sheets-Sheet 1 Nov.23,1948. QVM R v 2,454,710

STOP MECHANISM FOR SEWING MACHINES Filed June 12, 1945 '2 Sheets-Sheet 2 arm/0W Walter J]! yeis" Patented Nov. 23, 1948 STOP MECHANISM FOR SEWING MACHINES Walter Myers, Stratford, Conn., assignor to The Singer Manufacturing Company, Elizabeth, N. J a corporation of New Jersey Application June 12, 1945, Serial No. 598,949

3 Claims.

This invention relates to sewing machines and more particularly to stop mechanisms therefor which function to automatically stop the machine at the end of a stitching cycle.

In the stitching of certain types of material and articles in large scale production, electrically driven sewing machines operate for a considerable period of time without requiring the attention of an operator. It is not unusual for a single operator to have charge of a battery of machines and, to expedite the operation of these machines, it is desirable that each machine be equipped with a suitable stop mechanism which functions automatically to stop the machine when the stitching cycle is completed.

It is the primary objective of the present invention to provide a novel and improved stop mechanism which may be readily applied to a standard sewing machine, which stop mechanism is of simple construction and is efficient and dependable in operation.

Other objects, novel features and advantages of this invention will become apparent from the following specification and accompanying drawings, wherein:

Fig. 1 is a perspective view of a sewing machine unit equipped with the improved stop mechanism.

Fig. 2 is a fragmentary rear elevational view of the sewing machine bracket-arm, illustrating the preferred manner of attaching the stop mechanism to the machine.

Fig. 3 represents a fragmentary top plan view, partly in section, showing the details of the driving belt-pulley assembly and certain of the components of the stop mechanism.

Fig. 4 is a fragmentary front elevational view of the sewing machine with the stop mechanism positioned in normal running position.

Referring to the drawings, the sewing machine chosen to illustrate the present invention is constructed substantially in accordance with the disclosure in my copending application Serial No. 516.158, filed Dec. 30 1943. now Patent 2406,623 dated August 27, 1946. The sewing ma chine frame comprises a bed I, from one end of which rises a hollow standard 2 supporting a tubular bracket-arm 3 which terminates in a head 4; all supported in an elevated position. by a pedestal 5. cation in the head 4, is a conventional needlebar 6 carrying at its lower end a needle 1 having cooperating therewith beneath the bed I a suitable form of loop-taker not shown- The needle I and loop-taker cooperate in the formation of Journaled for endwise reciproposed endwise slidable belt-shipper rod 29.

stitches in material fed beneath the usual presser-foot 8 by a feed-dog 9 actuated in a manner fully disclosed in the U. S. Patent of S. Zonis, No. 2,267,581, Dec. 23, 1941.

The machine is operated by power applied; through a driving belt Hi, to a main-shaft journaled in ball-bearings l2 supported by the bracket-arm 3. Suitable connections with the main-shaft operate the stitch-forming mechanism and the feeding mechanism. In addition to the feeding mechanism, exemplified in the present case by the feed-dog 9, the material to be stitched is adapted to be directed toward the stitching mechanism by a work-guide l3 which is supported on a carrier l4. The work-guide I3 and its carrier l4 are adapted to be fed transversely of the normal line of feed in a direction toward the standard 2 by a lead-screw l5 freely journaled in spaced bearing-lugs l6 and I1 integral with a bracket l8 secured by screws H! to the pedestal 5. For a complete disclosure of the means employed for turning the leadscrew 5, reference may be had to my above mentioned co-pending application.

It is the purpose of the present invention to provide a stop mechanism which will automatically interrupt the driving relationship between the belt Ill and the main-shaft l I when the workguide |3 reaches a predetermined inner position. To that end, the stop mechanism which I have provided comprises a supporting bracket 20, preferably cast into U-shape to conform to the external shape of the bracket-arm 3 and to extend from the front of the bracket-arm over the top of the same so as to terminate in a supporting lug 2|. The lug 2| is apertured, as at 22 (Fig. 2), to receive the screws 23 which secure the bracket 20 seated upon a boss 24 preferably cast integral with the regular cover-plate 25 fastened by screws 26 to the rearward side of the bracket-arm 3.

At the front of the machine, the supporting bracket 20 has a pair of spaced lugs 21 and 28 bored to provide bearings for a horizontally dis- Secured to the outer end of the rod 29, preferably by'a screw 30, is a bifurcated belt-shipper mem-- ber 3| the spaced limbs 32 of which are positioned to straddle the driving belt Ill.

As will be observed in Fig. 3, the driving belt I0 is adapted to run on a pulley assembly including a loose pulley 33 and an adjacent fast pulley 34. The fast pulley 34 is preferably formed. integral with the regular balance-wheel 35which has a'web portion 36 and a double ended hub-sleeve 31. The balance-wheel 35 is secured to the shaft H by the set-screw 38. The loose pulley 33 surrounds the outer hub-sleeve 31 and has interposed between it and the hub-sleeve a ball-bearing 39.

Surrounding the rod 29, between the bearing lugs 21 and 28, is a coil-spring 40 of which one end bears against the lug 21 and. the other end bears against a collar 4| adjustably clamped upon the rod 29, preferably by a screw 42. To

prevent turning of the rod 29 in the bearing lugs 21 and 2B, the collar M is provided with a guidepin 43 which, as shown in Fig. 3, projects into an elongated guide-slot 44 formed in the supporting bracket 20. The coil-spring 4B is under compression and functions to bias the rod 29, together with the belt-shipper member 30, in a direction to maintain the parts in the position shown in Figs. 1, 2 and 3. When the parts are in this position, the driving belt I is on the loose pulley 33 and the sewing machine is stopped.v

To maintain the parts in the position shown in Fig. 4, in which position the driving beltruns on the fast pulley 34, I have provided a latchlever 45 pivotally supported on a fulcrum-stud 46 threaded into an extension 41 of the lower end of thesupporting bracket 20. The latchlever 45 is preferably formed of two arms of which one curves upwardly and terminates in a sharp nose 48 adapted releasably to enter a notch 49 formed in the belt-shipper rod 29. The nose 48 is influenced to enter the notch 49- by' a spring 50, one end of which is anchored in the extension 47 while the other end is anchored in a hole I formed in the latch-lever 45. The other arm of the latch-lever 45 extends downwardly and terminates just short of the bed i adjacent the standard 2. This arm is adapted to be contacted by the inner end of a trip-rod 52' endwisc adjustably secured, preferably by means of a set-screw 53 (Fig.3), in the carrier M of the work-guide [3. To facilitate properly setting the trip-rod 52 in the carrier l4 and returning of the work-guide l'3' to the proper start stitching position, there is adjustably clamped on the triprod an indicator block 542 having a reference line 55 adapted to cooperate with suitable indicia 56 scribed in the bed i..

In order conveniently'to shift the belt-shipper rod 29 from its stop-position, as shown in Fig. 3, to its machine-running position, as shown in Fig. 4', there is secured on the rod 29 a handoperated throw-in member 51. Projecting rearwardly from the member 51 is an arm 58 carrying brake-pads 59' which are adapted to engage the side-wall 60 of the balance-wheel 35, thereby to brake the machine to an early stop when the belt Ill is shifted from the fast pulley 34 to the loose pulley 33.

When it is desired to sew an article, which in the present case is a hat-brim, the work-guide I3 is located" so that the right-hand marginv of the hat-brim is properly positioned with. re: spect to the needle I and the feed-dog- 9. The operator then grasps the throw-in member. 51 and shifts the belt-shipper rod 29 to the. left (Figs. 1' and 3'), thereby disengaging the brake pads 59 from the balance-wheel 35 and moving the driving belt from the loose pulley 33 to the fast pulley 34. As the belt-shipper rod is shifted, the notch 49 in the rod is brought into regisin machine-operating position, as shown in Fig. 4;. Stitching of the hat-brim is thus begun and.

as the work-guide l3 travels transversely of the direction of feed in response to the rotating feedscrew [5, the trip-rod 52 carried by the workguide carrier I4 approaches the downwardly extending arm of the latch-lever 45. At a predetermined time, the trip-rod contacts the arm of the latch-lever 45 and swings it about the fulcrum-stud 46, thus releasing the belt-shipper rod 29. The belt-shipper rod under the influence of the compression spring 40 snaps to the right, thereby moving the driving belt [0 from the fast pulley 34 to the loose pulley 33 and applying the brake to the balance-wheel.

From the above description, it will be appreciated that I have invented a simple, compact and efilcient stop mechanism which is in the form of an attachment capable of being applied to existing standard sewing machines with a minimum of modification. It will be noted also that the stop mechanism, when applied to the machine, is disposed in close proximity to the machine-frame and does not encroach upon the work-clearance area beneath the bracket-arm. The hand-operated throw-in member 51 is 10- cated for convenient manipulation by the operator. It will be understood that the machine may be quickly stopped at any time before the completion of the stitching cycle by merely manually tripping the latch-lever 45.

Having thus set forth the nature of the invention, what I claim herein is:

1. A unitary stop mechanism attachment adapted for use on a sewing machine having a belt-driven rotary actuating member, comprising, a supporting bracket formed with a guideslot, a belt-shipper rod provided with a notch and journaled in said supporting bracket for endwise movement into a machine-stop position and a machine-running position, a belt-engaging member fixed on said rod, a brake-element also fixed on said rod, a latch pivotally mounted on said supporting bracket and adapted to enter the notch in said belt-shipper rod to hold said rod in its machine-running position, a spring for biasing said rod into its machine-stop position, in which position the brake-element is adapted to engage said belt-driven rotary actuating member, and a guide carried on said rod and coopcrating with said guide-slot for maintaining said belt-engaging member in cooperative relationship with the belt.

2. A unitary stop-motion device for a sewing machine having a frame provided with a boss and a rotary belt-driven actuating member, comprising, a supporting bracket having a seat adapted to be secured to said boss and having its body-portion shaped to extend from said boss over the top of and down the opposite side of said frame in conformity with the contour thereof; said supporting bracket being'provided at its end remote from the seat with spaced bearing lugs, a belt-shipper rod 'journaled in said hear-- inglugs and having a machine-stop position and a machine-running position, a beltengaging member carried by said rod, a hand-operated throw-in member also carried by said rod, a brakeelement, spring means for urging said rod into its machine-stop position in which position said brake-element is adapted to engage said rotary belt-driven actuating member, and a latch pivoted on said supporting bracket and engageable with said belt-shipper rod for holding the same in its machine-running position with said brake-element out of contact with said rotary belt-.driven actuating'member.

3. A unitary stop-motion assembly unit adapted for use on sewing machines, comprising, a generally U-shaped supporting bracket having one arm thereof provided with a supporting seat and having its other'arm provided with bearing means and an extension, a belt-shipper rod journaled in said bearing means for movement crosswise of said supporting bracket, a spring for biasing said shipper-rod in one direction, a brake-member limiting movement of said shipper rod under the action of said spring, a handoperated throw-in member associated with said braking member, a two-armed latch-lever pivotally mounted on said supporting bracket extension, and means provided upon said rod for en- 15 gagement by one arm of said latch-lever.

WALTER MYERS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 409,963 Hart Aug. 27, 1889 417,333 Paulmann Dec. 17, 1889 638,182 Leilich Nov. 28, 1899 976,399 Rosenthal Nov. 22, 1910 1,173,162 Bassett Feb. 29, 1916 1,263,857 Clarke Apr. 23, 1918 1,659,937 Allen Feb. 21, 1928

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