US697041A - Variable-motion mechanism. - Google Patents

Description

N0. 697,04I. Patented Apr. 8, l902.. 5

A. B. TENNEY. VARIABLE MOTION MECHANISM.

(Application filed May 24, 1901.)

(No Model.)

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i rrh STATES a PATENT OFFICE.

ALBERT B. TENNEY, OF EVERETT, MASSACHUSETTS.

VARIABLE-MOTION MECHANISM.

SPECIFICATION forming part of Letters Patent N 0. 697,041, dated April 8, 1902.

Application filed May 24, 1901.

To aZZ whom it may concern:

Be it known that I, ALBERT B. TENNEY, a citizen of the United States, and a resident of Everett, in the county of Middlesex and State of Massachusetts, have invented a new and useful Improvement in Variable-Motion Mechanism, of which the following is a specification.

My invention relates to the class of devices used for imparting movement to a shaft at diiferent rates of speed; and the object of my invention is to provide a device of this class that shall have a greater efficiency than devices of the prior art and one that shall also simplifytheconstruction. Adevicebymeans of which these objects may be attained is illustrated in the accompanying drawings, in which Figure l is a view in side elevation of a portion of a metal-working machine, showing the variable motion attached thereto, the latter being shown in side elevation. Fig. 2 is a detail view, in longitudinal section, through the device.

In the accompanying drawings the letter a denotes a portion of the frame of a metalworking machine, on which frame is supported a cam-shaft 1), bearing a cam-wheel c. This cam-shaft is driven by means of a worm cl, meshing with a Worm-wheel (not shown) secured to the camshaft b. The worm d is secured to a driving-shaft e, which is supported in the usual manner in bearings a on the frame of the machine.

All of the parts just described are of usual and well-known arrangement and construction, myinvention relating particularly to the means for driving the shaft 6 at different rates of speed.

The means for controlling the movement of the shaft e at different rates of speed consists of a cam c, secured to the cam-wheel c and operating upon a stud on the under side of a rocking lever pivoted on a web a on the frame of the machine. One arm f of this lever engages a sliding bar g, to the end of which is secured a yoke g. This yoke overarches a portion of the mechanism, and the end of the yoke rests in a circumferential groove in a clutch member h, which is splined to the shaft 6. This clutch member bears pins 72/, secured to its face.

Serial No. 61,720. (No model.

A driving-pulley z' is loosely mounted on the.

shaft 6, and the hub a" of this pulley 2' forms a clutch member cooperating with the clutch member h. In the hub iare located pins -i ,that project fromthe face of the hub and cooperate with the pins h in the clutch member h to connect the parts. These pins 1' are seated on springs i so that when the clutch member h is moved toward the pulley 11, as by means of the cam c, lever f, bar g, and yoke g, should the pins lie opposite each other the pins 1' may retreat within the sockets in the hub t" until the part It has been rotated sufficient-1y to allow the pins to slide past each other, and thus avoid any breaking of the pins or other parts of the machine in the operation. Then the pins are in engagement with each other, the shaft is driven at the same rate of speed as that at which the pulleyt' is turning. When, however, it is desired to drive the shaft at a difierent rate of speed, the following mechanism is put into opera tion:

A ratchet-wheel k is loosely mounted on the shaft 6, and a pawl Z, pivoted to an upward-projecting part from the web a ,is adapted to engage the ratchet to prevent backward movement thereof. This ratchet has a hub on which is loosely mounted a plate m. This plate bears a stud m, on which is loosely mounted a pinion 'n, the pinion being free to rotate on the stud. This pinion is in mesh with an internal gear q, formed on a flange from the pulley 2', and the pinion also meshes with a pinion 0, secured to the hub 70' of the ratchet 7c. The pinion it also meshes with a pinion p, keyed to the shaft e. The pinions o and 19 have a different number of teeth, in the form shown the pinion 19 having one more tooth than the pinion 0.

In the operation of the device when it is desired to rotate the shaft 6 at a high rate of speed the cam c is so located as to swing the lever f, whereby the yoke g is moved to cause the pins on the clutch member h to engage the pins z' in the clutch member 2'. When these parts are engaged, the shaft e is rotated at the same rate at which the pulley t' is rotated and in the same direction. When it is desired to operate the shaft at a slow rate of speed, the cam c is caused to move the yoke g, so that the pins are disengaged,

the pawl Z being in engagement with the ratchet 7c. The tendency is to now. move the ratchet k backward; but it being held by the pawl Z the shaft 6 is caused to rotate in the same direction as the pulley 2', but at a very much slower speed.

The sliding bar g is engaged by the arm f of the rocking lever f, the end of the arm being located between the stops g 9 One at least of these stops is adj ustably secured to the bar in the form shown herein, the stop g being so secured, a bolt 9 passing through a longitudinal slot in the bar, by means of which the desired amount of adjustment may be secured. This adjustment of the stop pro- .vides means whereby any variation between the dogs on the cam-wheel for throwing the clutch in and those for throwing the clutch out that may have occurred for any reason maybe equalized. This adjustment is also found advantageous in renewing the pins in the clutch parts to compensate forany variation in the pins.

Iam aware that it is not new to provide a device of this character with a pinion rotating about and in mesh with the teeth of two other pinions bearing a different number of teeth and one of which is secured to a shaft and the other free to rotate thereon, but held 3o1against backward movement by means of a ed on the plate and in engagement with the 1 pinions hereinbefore mentioned, and a gear on the pulley adapted to engage the pinion on the plate.

3. Arotatable shaft, a pulleyloosely mounted on the shaft but adapted to be connected to rotate therewith, said pulley having an in ternal gear, a ratchet loosely mounted on the shaft, a pawl to engage the ratchet, a pinion rigidly connected with the ratchet, a pinion secured to the shaft, said pinions having a different number of teeth, a plate loosely mounted on the shaft, and a pinion mounted on the plate and in mesh with said internal gear, and also with the pinions hereinbefore mentioned.

4. In a fast and slow motion mechanism, in combination, a rotatable shaft, a pulley loosely mounted on the shaft, a clutch-section splined to the shaft and adapted to be engaged with the pulley, a pinion loosely mounted on the shaft, means for preventing backward movement of said pinion, a pinion secured to the shaft, a plate loosely mounted on the shaft, a pinion in engagement with said pinions hereinbefore mentioned, and a gear on the pulley in engagement with the pinion on the plate.

ALBERT B. TENNEY.

Witnesses:

F. G. RoYcE, M. LEON WALKER.

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