Untitled record

Application filed June 14,1881. (No model.)

To all whom it may concern:

Be it known that I, Hugo Borchardt, of the city and State of New York, have invented certain Improvements in Speed-Regulating 5 Devices for Sewing-Machines, of which the following is a specification.

My improvements relate to that class of speed - regulating devices heretofore extensively employed in connection with sewingio machines in which,the operator is enabled to alter the speed of the machine without stopping it by holding a lever in variable positions.

In such devices heretofore the treadle has 15 usually been provided with aretracting-spring, and the variability in the speed of the machine has been attained by pressing the treadle against the force of the spring with different degrees of force, so as to hold the spring in a 20 more or less compressed condition.

One distinctive characteristic of the mode of operation of my improvement is that the treadle for altering the speed of the mechanism is not worked against a spring, and therefore keeps 25 any position in which it may be placed, so that continued pressure upon the treadle is not required in order to preserve the speed of the machine at any given rate.

My invention consists in the combination of 30 a treadle with means for transmitting power to the. counter-shaft, carrying the pulley to which the machine is belted, consisting of a friction-disk affixed to a longitudinally-movable shaft and rotating upon an axis at right 35 angles to the axes of the counter-shaft and of the line-shaft, and bearing upon opposite sides of its periphery against the. faces of two disks, respectively affixed to the counter-shaft and the line-shaft, the face of the disk of the 40 counter-shaft being held against the periphery of the intermediate friction-disk by elastic pressure. The shaft upon which the intermediate or transfer disk is mounted is so connected with the treadle that it may be moved 45 longitudinally in either direction by rocking the treadle. The movement of the transferdisk toward the axis of the line-sb aft diminishes the diameter of that part of the disk upon the line-shaft which drives the transfer-disk and 50 increases the diameter of that part of the disk upon the counter-shaft which receivesitsmotion from the transfer-disk. On the contrary, when moved in the opposite direction, the diameter of that part of the disk upon the line-shaft which acts upon the transfer-disk is increased, and, 55 on the other hand, the transfer-disk acts upon the disk on the counter-shaft ata point nearer its center, and thus increases the speed of the counter-shaft. The transfer-disk remains in any position in which it may be placed, and 60 the speed of the counter-shaft, and hence the speed of the machine, is therefore constant so long as the treadle is not moved. The frictional hold of the transfer-disk upon the disk on the counter-shaft is maintained by an expand- 65 ing spiral spring on the counter-shaft, which constitutes a part of my invention. In case of a sudden strain upon the machine this spring will yield and allow the transfer disk to slip over the surface of the counter-shaft disk. In 70 connection with this spring, and to enlarge the capacity of the machine to which the apparatus is applied, I arrange a withdrawinglever, which can be,if desired, connected with and operated by the treadle-shaft. 75

In doing a class of work in which no systematic variation in the speed of the machine is required, I may disconnect from the treadle the shaft of the transfer-disk and connect it with the withdrawing-lever, by the action of 80 which the disk on the counter-shaft is withdrawn from contact with the periphery of the intermediate disk whenever it is desired to stop the machine.

Myspeed-regulator maybe usefully employed 85 for sewing-machines or for any other class of partially-automatic machines in which the services of an operator are required, and in which contingencies are liable to arise requiring variations in the speed of the machine. 90

The accompanying drawings, representing my speed-changing mechanism, are as follows: Figure 1 is a top view. Fig. 2 is a front elevation, partly in section.

The drawings represent a line-shaft, A, for 95 rotating continuously at a given speed. The line-shaft is provided with a disk, a, the side of which engages the periphery of the transferdisk b, the shaft of which is seated in au arm, b', affixed to the longitudinally-sliding bar B. ico The periphery of the transfer-disk b is preferably covered with leather or some other par»

246,36» tially-elastic material. The transfer-disk is rotated by the engagement of its periphery with the face of the driving-disk a.

Tbecounter-shaft 0 is provided with the disk 5 c, which, it will be seen, has a dished edge, c'. The object in dishing the edge of the disk c is to release it from engagement with the periphery of the transfer-disk b when the transferdisk is pushed inward to a point opposite the io dished part of the disk c. When the position of the transfer-disk δ is such that it engages both the disk a and the disk c the countershaft C is rotated with greater or less speed according to the ratio of the distances of the 15 axes of the disks a and c from the points of their engagement respectively with the transfer-disk b. The counter-shaft is provided with the pulley C' for engaging the belt wbich drives the machine. The expanding spiral spring c², 20 surrounding the counter-shaft O, bears at one end upon the washer c³, supported against the end of the journal C³, and at the opposite end bears against the clamp-collar c⁴ and thrusts the disk c into the position in which it is rep25 resented in the drawings, in which, as will be seen, the transfer-disk is pushed inward to a point opposite the dishing part c' of the disk c, and is not in contact therewith. When the transfer-disk is pulled outward, so as to en30 gage the face of the disk c, the spring c² yields, allowing the disk o to move back.

The sliding movement of the transfer-disk is effected by moving the slide-bar B, to which the arm V is affixed. This is effected by means 35 of the rocking lever B', the slotted end B² of which loosely engages the pin b², projecting downward from the hub b³ of the arm b', iu the upper end of which the shaft of the transferdisk b is journaled. A spring, b¹, attached to 40 the end B² of the lever B', tends to push the arm b' over, so as to remove the transfer-disk from contact with the driving-disk a when the transfer-disk is opposite the dished edge of the counter-shaft disk c, and the machine is 45 not in use.

The oscillation of the lever B' is effected by means of the treadle D, through the pitman B³, affixed at one end to the end B‘of the lever B', and at the other end to the pin d, inserted trans50 versely in the arm d', projecting upward from the hub d², through which the treadle rockshaft I)' passes, and which is provided with a set-screw, d³, by which it may be fastened to and made to move with the rock-shaft D'. 55 In some classes of work in which it may not be necessary to vary the position of the transfer-disk from that in which it imparts a prescribed speed of rotation to the counter-shaft, and in which the spiral spring c² affords all the 60 necessary protection against a sudden strain on the machine, the hub d² may be loosened from the treadle rock-shaft D' by unscrewing the set-screw d³, and the motion of the machine may be arrested, when required, by means of 65 the withdrawing-lever E, provided at itsinner end with the upward projection, e, carrying the brake-block c', which is made to bear upon the face of the disk c, and to push the disk backward out of engagement with the transfer-disk by means of the rocking-lever E', one 70 end. E², of which is seated in the curved recess E³, formed in the edge of the withdrawing-lever E, while the other end, E⁴, of the rockinglever, E',is connected by means of the pitman E⁵ with the pin F, inserted transversely into 75 the arm/, projecting upward from the hub/'. The treadle-shaft D' is inserted through the hub/', which is provided with the set-screw/², by means of which it can be fastened to and made to move with the treadle-shaft D'. 80

It will, of course, be understood that when the transfer-disk is to be used for varying the speed of the machine the set-screw/² will be loosened, so that the rocking of the treadle-lever will have no effect upon the train of mech- 85 anism which actuates the withdrawing-lever; and, vice versa, wheu the withdrawing-leveris to be used, the set-screw d³ will be loosened, in order that the treadle-lever rnaynot actupon . the hubd², which actuates the system of levers 90 for changing the position of the transfer-disk.