US1498649A - Stop-motion mechanism - Google Patents

Description

June 24 1,924

A, F. FIFIELD STOP MOTION MECHANISM Filed Dec. 20. 1919 I5 Sheets-Sheet l mg W mw June 24, 1924.. I 1,498,649

v A. F. FIFIELD sToP Mo'rloN MEHANISM Filed Deo. y2o. 1919 s sheets-snee; 2

VWM" yf ATTORNEY June 24 1924. @$8,649

' A. F. FlFLD STOP MOTION MECHANISM- Filed Dec. 204 1919 3 SheetsSheet 5 ATTORNEY ALBERT F. FIFIELD, OF NEWARK, NEW JERSEY, ASSIGNOR TO THE SINGER MANUFAC- TUBING COMPANY, O'F ELIZABETH, NEW JERSEY, A CORPORATION OF NEW JERSEY.

AppIication filed December 2O,r 1919. Serial No. 346,346.

T 0 @ZZ whom 'it may concer/n.'

Be it known that I, ALBERT F. FIFIELD, a citizen of the United States, residing at Newark, in the county of Esse);l and State of New Jersey, have invented certain new and useful Improvements in Stop-Motion Mechanisms, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to an improvement in stop-motion mechanism for sewing machines and particularlyv to stop mechanism `for machines for sewing on buttons, barring, tackingor similar operations although it is by no means confined to use with this type of machine. n

Machines of this type have previously been operated at the relatively low speed of 1000 or 1200 stitches per minute. In my copending application Serial No. 294,034, filed May 1, 1919, l have disclosed a machine of this type adapted to be operated at a higher speed and an object of this invention is to provide an improved automatic bra-lie for the stop-motion which will lessen the shock of stopping at the high speed employed, reduce wear and tear on the stop-motion mechanism and quickly reduce the speed so that the thread-cutter mechanism which is actuated by the stop-motion, will not act upon the thread with toogreat abruptness. Another object is to provide means for regulating the action of the brake to suit.

different speeds. Y

This application is a division of n y above mentioned copending application Serial No. 294,034, filed May 1, 1919.

ln its preferred form the invention comprises a brake mechanism adapted to act upon the driving pulley of the machine and connected with the stop-motion in such a way that it is applied as soon as the stoplever is tripped but is released and reset for the next application by a shock absorbing movement of the stop-lever as the machine comes to a stop. The force for applying the brake is obtained from a spring which is provided with means for varying thev brak-Y ing effect. i

Referring to the accompanying drawings. Fig. 1 is a front elevation of the machine. Fig. 2 is a rear elevation of the standard and its associated mechanism. Fig. 3 is an end view from the right of Fig. 1. Fig. 4 is a bottomplan view of the end corresponding to Figs. 2 and 3. Fig. 5 is a detail horizontal section above the work-plate at the'right hand end of Fig. 1, and Fig. 6 is a perspective view of the catch mechanism. for the brake. f,

AThe numeral 1designates the b ase of the work-plate of the machine fromwhich rises the standard 2 carrying the overhanging armv 3 with head 4. mounted within the arm 3 and at its rear outer end carries the loose pulley 6 anda fast pulley 7. At its other end, shaft'5 has mechanism for operating the thread take-up arm andthe needle. Vithin the standard V2 shaft 5 has a beveled gearfconnection ,withr a vertical shaft 7 and the latter in turnvhas a bevel gear connection with a rotary looptaker shaft 8. ,The main-shaft 5 also carries a worm 9 meshing with the worin-wheel 10 on the transverse shaft 11 on which shaft is vmounted the controller cani-wheel 12, Figs. 1 and 2./ A jogging work-clamp and work-support ofwell lrnown form is provided, the same being indicated as awhole 'by the reference numeral 13. The Work-support `is lgiven movement transverselyand longitudinally of the work-plate from 'the A main-shaftv 5 isV controller cam-wheel `12 through the levers 14 and 15, respectively, as disclosed in 'the parent application. stantially those shown in the patents to Sullivan, No. 777 ,564, of December 13, 1904, rand Barron, No. 1,093,241, of April 14, 1914.

A stop-lever 16 is pivotally mount-ed in the lug 17 on the frame for movement on an axis transverse the length of the work-plate and carries a belt-shifter 18 secured nearits upper end; A spring-pressed'plunger 19 at the upper end of the lever, isadapted, when in proper position, toerigage a stoppingcam 2O on the main-shaft?) to stop the machine. The stop-lever also hasV a limited s'idewise shock absorbing movement after engaging the stopping cam, as it is pivoted on the member 21 which is mounted to turn in the.i

lug 17` The stop-lever is held vout of engagement with the stopping cam and inthe position Shown in Fig. 2 by means ofthe spring-pressed latch rear side of the lever.

cam-lug 23 (Fig. 1) on the inner side of the cont-rollerV cam-Wheel 12. rlvhe stop-motion These means are sub` ioo 22 which' engages' the l At the close 4of. a sewing operation this latch is released by a mechanism so far described is old and well known and is fully shown and described in the patent to Barron, No. 1,093,241. The coil-spring 24 is secured at one end to the lower end of the stop-lever 16 and at its other end to a pin 25 projecting below the base. This spring tends to move the stoplever to stopping position. in starting, the stop-lever is moved out of alinement with the stopping cam and into engagement with the latch 22 by means of the push-rod 26 (Figs. 1 and 4) located below the base and adapted to contact atone end with the lower end of the stop-lever. This push-rod is con- :j nected at its other end to the downwardly projecting arm 27 of a bellcranlr-lever pivoted to4 a lug on the lower side of the base. rllhe other arm 23 of' the bellcrank-lever may be connected to a treadle or other means for operating it by a chain 23. The coil-spring 29 surrounds the push-rod and is confined between a collar 30 and a bearing lug 31 whichv spring tends to normally hold the .PllShL-lod outoi' engagement with the stoplever.

@wing to the high speed employed it has been found desirable to use a brake to assist the stop-motion mechanism in stopping the machine. This brake comprises a brakeshoe 32,` adapted to bear against the tast pulley 7 and pivotally connected to the upper end of a brake-lever 33 pivoted on the frame at 34. .estY coil-spring 35 is connected at one end to4 the lower end of the brakelever and at its other end to an arm 36 projecting from a short vertical shaft 37 extending through and above the base. Abo-ve the base a finger-lever 33 provided with a thumb-screw 33 is connected to the shaft 37. rThe spring 35 tends to throw the brake into action and by means of the iinger-lever 33 and arm 36 tension of the spring may be varied to thereby vary the action of the brake at different speeds. The brake acts only between the time the stoplever is irst tripped to shift the belt and the time the shock absorbing motion of the stopnlfever takes place and the Jfollowing means are provided to secure this result. A. small contact lever 39 (Figs. 4 and 5) is pivoted at the rear oi the base at 40, one end of which lever is adapted to. be actuated by the lower end of the stop-lever 16 in its sidewise shock absorbing movement and the opposite end of the contact lever has a pivotalY connection at 41 with a sliding bar 41 having the cam-lug 42 engaging a camlug 43 on the lowerportion of the brakelever. The bar 41 also has a latching projection 44 engageable by one end of a latchlever 45 pivoted at 46` and pressed toward they projection by ay coil-spring 47. he othery end of the latch-lever 45 has a trip 43 pivotally connected thereto and yieldingly held in a position at substantially right angles to the lever by means of a coil-spring 49. A stop 45 on the lower side of the latch-lever 45 prevents the coil-spring 49 from pulling the trip 43 too far over.

The scribed in the parent application is operated by the slide-bar extending substantially the length of the machine. At its rear end the bar 50 carries a block 51 having a notch 52 entered by the reduced lower end of a lever 53 pivotally mounted at 54 on the bracket 55 secured to the iframe (Figs. 2 and rEhe upper end of the lever 53 carries a cam-follower movable in a cam-groove 54 in the cam-wheel 12. carries the roller-stud 56 engaged by a iiorlrarm 57 of a bellcranlr-lever i'ulcrumed at 53. rhe other arm 59 of the lever carries the plunger-pin 60 at its end which pin is pressed outwardly by a spring 61. The pin 60 is adapted to enter a recess 62 in the lower part oi' the stop-lever 16 just before the overthrow movement or the latter takes place. The above described means :tor actuating the slide-bar 50 and bellcranlzlever 57, 59 from the stop-lever and controller shown in the patent to Barron, 1,093,241 above mentioned.

In operation the stop-lever 1G is shifted by the treadle-connection 23 oiZ bellcranklever arm 23 which throws the belt to the fast pulley 7, moves outl the lower end ot the stop-lever and allows the trip 43 to slip behind it and allows the latch 22 to engage the lever 16. rlhe brake is in ineffective position and its operating parts are disposed as shown in Fig. 5, i. e., the sliding bar 41 is latched in its extreme right hand position, its cam-lug 42 has moved out the cam-lug 43 on the brake-lever 33 against 'the action of the spring 35: thereby freeing the brake and the trip 43 is in position to communicate the initial stopping movement oi the stopping lever 16 to the latch-lever 45 and free the latter from the projection 44 on the slide-bar 41. The stitching then proceeds in the manner usual with machines of this type.

At the finish of a sewing operation the needle makes several thrusts in the same hole to 'form tying stitches. As the needle comes down on its last reciprocation, the cam projection 23 engages the latch 22 and releases the stop-lever 16 which latter is at once acted upon by its spring and shifts the belt to the loose pulley and draws the plunger 19 into the path of the stopping cam 20. The lower end of the stop-lever pressing on the trip 43 releases the latch 45. rlhe brake-lever i spring 35 immediately throws the brake into action and as the lower end of the brakelever moves inwardly the cam-lug 43 acts upon the cam-lug 42 forcing the slide-bar 41 to the lett as viewed in Fig. 5 and the lever thread-cutting mechanism as deif The block 51 also cam-wheel are substantially those 39 to the right and in contact with the stoplever. The main-shaft continues to turn due to its momentum and the passing of the follower on the lever 53 up the incline to the projection `54 of the cam-wheel moves the slide-bar connected to the cutter mechanism. The bellcrank-lever 57, 59, being also connected to the slide-bar 50 is likewise moved and its plunger-pin springs into the recess 62 of the stop-lever 16 as it comes into alinement therewith. ,Finally the plunger 19 on the stop-lever 16 comes into engagement with a projection 20" on the stop-cam 20 causing a sidewise shock absorbing movement of the stop-lever against the action of a spring-pressed plunger mounted in the boss b. This sidewise movement is transmitted by the bellcranl-lever 57, 59, and slide-bar 50 vto the thread-cutter to give it its final thread-cutting movement as described in the parent application. As before stated, the means by which the lsidewise movement is imparted is substantially that shown in the patent to Barron, No. 1,093,241 and forms no part of my invention. As the sidewise or shock absorbing movement takes place the lower end of the stop-lever also actuates the .lever 39'which latter moves the slide-bar 41 to the right and the cam-lug 42 on said bar acts on the l'cam-lug 43 to force the lower end of the brake-lever 33 outwardly and release the brake. At the same time the latching projection 44 on the bar 41 comes in position to be engaged by the latch-lever 45 and the spring J 7 urges the latch into engagement with this projection. As the lower end of stop-lever 16 has moved to the left, Figs.

3, 5 and 6, in its sidewise movement the trip 48 can move outwardly along the right side of the lever 16 as the right-hand end of the latch-lever 45' swings outwardly. As the stop-lever 16 swings back from its sidewise movement it moves trip v48 slightly to the right against the tension of the spring 49 and when the lever is reset at the beginning of the next' sewing operation its lower end moves outwardly allowing spring 49 to pull trip 48 in rear of the lever again as shown in Fig. 5. Y j

The present machine is capable of the relatively high speed of 1800 stitches per minute and by use of applicants improved brake the machine is stopped without undue wear and tear on the stop-motion mechanism.

Having thus set forth the nature of the a lever actuated by said stop-lever in its invention, what I claim herein is 1. In a stop-motion mechanism, a stoplever having initial and final stopping movements, a driven pulley, a spring-pressed brake therefor, means normally holding'the brake out of action, means actuated by the initial movement of the stop-lever whereby said holding means is released and the brake applied, and means actuated by the final movement of the stop-lever whereby the lthe setting movement of the stop-lever.

brake is thrown `out and held in ineecti've position.

2. In a stop-motion mechanism, a shaft having a driven pulley, a positive stop including a lever having different movements, a brake for said pulley, yielding means tending to apply said brake, a spring-pressed latch for holding the brake out of action, means actuated by one movement of the lever whereby said latch is released andthe brake applied, and means actuated by another movement of said lever whereby the brake is released and the latch applied again.

3. In a stop-motion mechanism, a driven shaft, a positive stop therefor, a retarding means for the shaft, means for locking the retarding means in ineffective position, and means for throwing said retarding means into action prior to the action of the positive stop and for throwing out and locking the retarding means as the positive stop acts.

4. In a stop-motion mechanism, a driven shaft, a spring-pressed brake for said shaft, a stop-lever having a plurality of movements, a latch for holding lsaid brake out of action, means operatively associated with said lever for releasing said latch on one of the movements of the said lever, and means operatively associated with said'lever for causing said latch to be set again on another'- movement of said lever. I j

.5. In a stop-motion mechanism, a rotary element, a friction brake-element and a positive stop-element adapted for successive engagement with said rotary element, and means controlled by movement of the positive stop-element for throwing the brakeelement both into and out of engagement with the rotary element as the machine is brought to rest.

6. In a stop-motion mechanism, a rotary element, a friction brake-element and a positive stop-element adapted for successive action upon said rotary elementfsaid stopeleinent having a movement into ystopping position and a shock absorbing movement r,while arresting the motion of the rotary element, and means controlled by the respective movements of the positive stop element for throwing the brake-element into-and out of action. j

7. In a stop-notion mechanism, a retarding device, a positive stop including a stoplever having a plurality of stopping movements and a setting movement, a trip and stopping movements for respectively throwing in and out of action the retarding device, and means for resetting the trip on 8. In a stop-motion mechanism, a rotary element, a friction brake-element and a positiveIstop-element adapted for successive action upon said rotary element, and a plurality of separateelements successively acted upon by said stop-element for throwing the brake-element into and out of. action.

9. In a stop-motion mechanism, a positive Stop, a retarding device, an actuating connection adapted to be interposed between the two at the begin-ning of a work-cycle, means for tripping the positive stop into action at the close of a work-cycle, to thereby apply the retarding device, an-d means actuated by the positive stop at the end of the wor1 cycle for throwing out of action the retarding device.

10:.l In a stop-motion mechanism, a shaft having loose and fast pulleys and a' positive stop-member thereon, a brake for reta-rding the rotation of said shaft, trip controlled means for engaging said stop-member and Shifting the belt from the fast to the loose pulley, and means controlled by said trip-controlled means for shifting said brakeinto and out of action prior to the completion of the action of the positive stop.,

ll. In a stop-motion mechanism, a shaft, a positive stop therefor having a movement to stopping position. and a shock absorbing movement, a brake for said shaft, mea-ns for putting said positive stop and brake into action, and means actuated by the overthrow move-ment for releasing said brake.

l2. In a stop-motion mechanism, a shaft, a positive stop therefor having a movement to stopping position and a shock absorbing movement, a brake for said shaft, spring means for actuating said stopv and brake, means controlled by the revolution of said shaft for releasing said first means, and means,r actuated by the shock absorbing movement for withdrawing said brake from action.

13. In a stop-motion mechanism, a shaft, a positive stop therefor, a brake for said shaft, unitary means for tripping said stop and brake into action, automatic means for releasing said brake, and manual means for releasing said stop.

14. In a stop-motion mechanism, a shaft, a positive stop therefor, a latch for holding shaft, a latch for holding said brake out of action, means actuated by the movement of the shaft for tripping said rst latch, and means actuated by the movement of the stop for tripping said second latch.

l5. In a stop-motion mechanism, a shaft, a. positive stop therefor having stopping and shock absorbing movements, La latch for l'iold-ing the stop out of action, a brake for said shaft, a latch for holding said brake out of action, means actuated by the movement of the sha-ft for releasing said first latch, means actuated by the stopping movement to release said second latch, and means actuated by the shock absorbing movement for throwing said brake out of action and into engagement with its latch.

16. In a stop-motion mechanism, a shaft, a positive stop therefor having stopping, shock absorbing and setting movements, a brake for said shaft, a latch for holding said brake out of action having a trip for releasing it actuated by the stop' in its stopping movement, means actuated by the stop shock absorbing movement to aga-in engage the brake by its latch, and means governed by the setting movement of the stop for setting the tri 3.

17. n a stop-motion mechanism, a shaft having a positive sto-p member thereon, a stop-lever having a plurality of movements, a spring actuated brake for said shaft, brake trippii'ig means controlled by one of the movements of the stop-lever for rendering the brake effective, and brake resetting` means actuated by another movement of the stop-lever prior to the complete stopping of the shaft.

18. In a stop-motion mechanism, a shaft, a positive stop-member thereon, a bralie for said shaft, a stop-lever having movements longitudinally and transversely of said shaft, one of which movements engages the stop-lever with the stop-member and causes the brake to act, and means controlled b-y the other movement for releasing the brake.

19. In a stop-motion mechanism, a shaft, a positive stop-member thereon, a springpressed brake for said shaft, meansv for holding said brake out of action, a stop-lever having movements on axes at right angles to each other, one of which movements engages the stop-lever with the stop-member kand releases said holding means, and means actuatedv by the stop on its other movementfor releasing the brake and engaging it with said holding means.

20. In a stop-motionmecha-nism, a stoplever having a plurality of stopping movements, a shaft a brake therefor, means normally holding the brake in ineffective position, means actuated by the initial movement of the stop-leverA for vreleasing said holding the same out of action, a brake for said r.means, and' means actuated by a succeeding movement of the stop-lever for returning the brake to ineffective position.

2l. In a stop-motion mechanism, a shaft, a normally ineffective brake therefor, a positive stop for said shaft having a movement to stopping position and a second movement as the shaft comes to rest, means co-ntrolled by the first movement of the stop for applying the brake, and means controlled by its second movement for rendering the brake ineffective.

In testimony whereof, I have signed my name to this specification.

ALBERT F. FIFIELD.

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