US623139A - Speed-changer - Google Patents

Description

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Patented Ap`r. la, |899.

NITED STATES PATENT OFFICE,

IIENRYII. CUMMINGS, OF MALDEN, MASSACHUSETTS.

SPEED-CHANGER.

SPECIFICATION forming part of Letters Patent No. 623,139, dated April 148, 1899. K i Application tiled January 10, 1893. Serial No. 666,184. iNo model.) i

To @ZZ whom t may concern:

Be it known that l, HENRY l-I. CUMMINes, of Malden, cou nty of Middlesex, State of Massachusetts, have invented an Improvement in Speed-Changers, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

My invention relates to improvements in speed-changing mechanism whereby a machine which is operated from a continuously and uniformly running shaft in usual manner may be started at desired minimum speed, the speed being varied as required until the machine is to be stopped.

It is desirable and, in fact, necessary in operatinga large variety of machines .that the machine shall be startedY slowly rather than suddenly at full working speed and that when started the speed maybemade fasteror slower, as may be desired. Accordingly I have invented means by which the operator may through a starting-lever start the machine slowly and then by continuing the movement of the said lever may increase the speed as desired, the machine being slowed down and stopped by a reversal of said lever.

The details of construction of my invention are set forth in the accompanying description, reference being had to the drawings, and the invention is more particularly defined in the appended claims.

In the drawings, Figure l, in side elevation and partly in section, the drive-pulley being omitted for clearness, and Fig. 2, in front elevation, show my invention applied for purposes of illustration to a sewing-machine, the latter being largely broken away, sufficient thereof being shown to enable the operative relations of the parts to be understood. Fig. 3 is a top plan View of Fig. 2, the table and its supported mechanism being removed. Fig. 4 is an enlarged central vertical crosssection of the speed-changer.

For convenience of illustration I have herein shown my invention in connection with a patented to me, in which a drive-pulley B, op-v erated by a belt b from a main driving-shaft, is mounted loosely on a stud C, carried .by a

upper ends above the'branching arms d d" of the hanger D. These gears are normally held outturned, as shown in Fig. 3, by a suitable spring II, engaged at one end to the lever or arm g' of and connected to the gear G and at its other end to a pindxin the arm CZ ofthe hanger, a stop d2 being provided on the arm d to be engaged by a lug g2 to limit the outward swing of the gears G GQ The power-transmission rolls F F are hung loosely between the pulleys B and E', so that when the latter pulley is tightly pressed toward the drive-pulley B motion is communicated to it frictiona'lly through the rotation of said rolls. l

A coupling device or lever I, xedly pivoted at t', is provided, preferably, with an adjustable head z", clamped in its free end to bear on a cap e, closing the outer end of the sleeve-like hub c of the driven pulley, a spring J, compressed in a socket in the hanger D, bearing against one end of the lever I and tending to swing the head 1l' against headed stud Z', working freelyin a slot Z2 of the upright portion of the treadle. n The upper free end of lever K has an overhanging linger kadapted to engage one end of the lever I and hold it down against the spring J mentioned, and a shoulder 7a4 to engage arm g of gear IDO G when the lever K is 'moved back out of its engagement with lever I.

From the foregoing description it will be evident that, the parts being in the relative positions shown in the drawings, if the operator depresses the treadle L, thereby throwing the lower end of lever K to the rear, the upper end of said lever -will be thrown forward, withdrawing the finger k3 from its holding engagement with the arm or lever I, permitting the spring J toA swing the lever I at once against the pulley E', thereby starting the machine by the engagement of the pulley E with the rolls F IW, the latter being frictionally driven by the pulley B. The machine having thus been started, if itis desired to run it fasterthe speed is increasedby continuing to depress the treadle, thereby bringing the shoulder h4 into engagement with arm g and swinging the gears G G to the left, Fig. 3, and consequently separating.

spondingly decreased on the driven pulley,

thus gaining the required speed. Upon stopping the machine the raising of the treadle either positively by the foot or automatically by spring H operates iirst to permit the spring Hto swing the gears G G to the right, as shown in Fig. 3, thereby correspondingly turning the rolls and slowing down the machine, then to permit the iinger k3 to engage the lever I and withdraw the latter fromengagement with the driven pulley, and final-ly to apply the brake 7c to the driven pulley and positively stop the machine. All these successive operations are accomplished simply by one operation of the treadle.

I have shown the rolls and their gears or such other connecting devices as may be employed arranged to start the driven pulley at the same initial speed as that of the drivepulley; but it is evident that this may be varied as desired by changing the inclinations of the rolls and by changing the arrangement 'and connections of the gears or their equivalents used; also, I have shown various pivoted members or levers; but it is evident that these members need not be pivoted, as other movements may be substituted.

It is to be borne in mind that my invention is intended for a- Wide range of uses, being shown in connectionwith a sewing-machine for convenience merely; nor is it limited to simple reverse movement of said lever the4 machine is slowed down, the power is thrown on, and the machine is stopped. This cycle of movements takes place invariably, so that, for instance, a careless workman cannot suddenly couple the machine for its topmost speed and thereby break the machine or ruin the material being operated upon or perhaps injure himself, but the machine will start and stop in one way only-viz., with an initial and final slow movement.

Various changes in details of construction,

arrangement, and combination of the parts of my invention as herein embodied may be resorted to without departing from the spirit and scope of my invention.

Having described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. The combination withpower mechanism, a machine to be operated, and intervening speed-changing mechanism, of an operating member, and a spring-actuated device for couplingsaid machine to said speed-changing mechanism, saidrdevice being separate from and independent of said speed-changing mechanism, said operating member normally holding said coupling device in inoperative position, substantially as described.

2. The combination with power mechanism, a machine to be operated, and intervening speed-changing mechanism, of an operating member, a coupling device for coupling said machine to said speed-changing mechanism, said coupling device being separate from and independent of -said speed-changing mechanism, and automatic means normally maintaining said coupling device in inoperative position, substantially as described.

3. The combination with power mechanism,

`a machine to be operated, and intervening speed-changing mechanism, of an operating member, a brake actuated by said operating member to stop said machine, a coupling device to couple said machine to said speedchanging mechanism, and automatic means normally maintaining said coupling device in inoperative position, said brake being applied simultaneously with the movement of said coupling device into inoperative position,substantially as described. v

4. A positively-driven friction-pulley, avariable-speed pulley mounted concentrically therewith, friction-rolls journaled between said two pulleys on arms extending beyond s aid pulleys, to-rotate in planes perpendicular to the faces of said pulleys, intel-meshing toothed segments fast on the projecting ends ofsaid arms, an operating member for positively moving said gears in one direction, and automatic means for giving an opposite movement, substantially as described.

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5. Apositively-driven friction-pulley, a val riable-speed pulley journaled face to face with said pulley, friction-rolls between and to engage said two pulleys, said rolls having their shafts projecting from arms extending beyond said pulleys, intermeshing segmental gears iixed on said arms, a lever extending from one of said gears, a spring normally moving said lever in one direction, and an operat- `with said roll, a coupling device to move it into driven engagement with said roll and said drive-pulley, said roll having a lever for shifting the position of said roll between said.l

pulleys, an operating member normally engaging said coupling device and holding it out of coupling engagement, said' member being arranged in the path of said lever and between the latter and said coupling device, substantially as described.

7; A speed-changing mechanism compris= ing a drive-pulley, a driven pulley, a friction= roll between said pulleys, the driven pulley being normally out of driven engage mentwitli said roll, a coupling device to moveit into driven engagement with said roll and said drive-pulley, said roll having a lever for shift-y ing the position of said roll between said pulleys, an operating member normally engaging said coupling device and holding it out of coupling engagement, said member being ar ranged in the path of said lever and between the latter and said coupling device, and a spring normally holding said lever-in engagement with said operating member, substan# tiallyvas described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses. y Y

HENRY H. CUMMINGS. Witnesses:

JOHN C. EDWARDS, AGUSTA E. DEAN.

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