US339893A - Assig - Google Patents

Description

(No Model.)

A. D. JEFFREY.

MEGHANIGAL MOVEMENT.

WITNESSES: ME Q @J By his Attorney's, or

. fication.

Uni-ran @TATES Fares-r Genres.

ALBERT D. JEFFREY, OF BROOKLYN, NEW YORK, ASSIG OR OF ONE HALF TO \VILLIAM SANDERSON, OF SAME PLACE.

MOVEMENT.

SPECIFICATION forming part of Letters Patent No. 339,893, dated April 13, 1886.

Application filed September 16, 1885.

To all whom it may concern:

Be it known that I, ALBERT D. JEFFREY, a citizen of the United States, residing in the city of Brooklyn, in the county of Kings and State of New York, have invented a certain new and useful Improvement in Mechanical Movements, of which the following is a speci- This invention relates to mechanism for the transmission of continuous rotary motion from one shaft to another, the object being to provide a means of multiplying the speed with less loss of power through friction than when gearing is used.

The distinguishing feature of my improved movement is the combination of a crank or cranks on the driven shaft, a cam or cams on the driving-shaft having a cycloidal groove or slot, and -a connecting-rod jointed at one end to the crank, and terminating at the other end in a roller which travels in said groove or slot, being suitably guided so as to restrain its movement to a direction toward and from the axis of the driven shaft.

Figure 1 of the accompanying drawings isa front elevation of my improved movement. Fig. 2 is a vertical section (on the line 2 2 in Fig. 3) showing one cam, crank, and connect ing-rod. Fig. 3 is a plan of the movement, and Fig. 4 is a view answering to Fig. 2, and showing a modification.

Let A designate the drivingshaft, and B the driven shaft. On the driving-shaft are iixed two cani-disks'C C, and on ihe driven shaft are two cranks, D D.

E E are two eonneoting-rodsorpil men, each jointed at one end to one of the cranks, and bearing on its other end a roller, 6. This roller enters a groove or slot, 0, in the correspond ing cam O. This slot isjust sufiiciently wide to receive the roller freely, without allowing it any lost motion or play between the sides of the slot. The slot 0 is cycloidal, its axis (indicated by dotted line a: in Fig. '2) being a cycloidal curve, such as would be generated by a pendulous reciprocation executed during a uniform rotation of the cam-disk and in a direction toward and from its center.

The slots in the cams shown in Figs. 1, 2, and 3 represent two complete reciprocations to one revolution, while that shown in Fig. 4

Serial No. 177,297. No model.)

represents three complete reciprocations to a revolution. The mechanism shown in the former figures is designed for transmitting to the driven shaft twice the speed of the driver, while that shown in the latter figure is designed for transmitting to the driven shaft three times the speed of the driver.

Each roller e, or the end of the connectingrod bearing the roller, is so mounted or guided that it can move only in a direction toward and from the center of the driving-shaft, and substantially in a straight line extending be tween the axes of the two shafts. The preferable way of thus guiding the roller is to sus- 6 pend it by a pendulous arm, F, from a fixed point, f, overhead, as shown most clearly in Fig. 2.

One of the cranks l) D is set on the shaft 13 ninety degrees, or one-fourth of a revolution, 79 in advance of the other, and the corresponding one of the cams O C is set on the shaft A. forty-five degrees, or oue-fourth ofa half-revolution, in advance of the other, as shown in Fig. 1.

The operation is obvious. As the shaft A revolves with its cams, the sinuous slot 0 in each cam forces the roller c(swing.ing from the center f) to reciprocate, and its motion is trans mitted through the rod Eto the crank D, which 80 it drives, the crank executing two revolutions to each revolution of the cam. By reason of one set of cams and cranks being set in advance of the other, asjust described, the two cams and cranks work alternately, each being at its phase of maximum advantage while the other 's passing the dead-point. The motion 'is very smooth and free, the shaft B being driven with the minimum of friction.

My invention is adaptable to various uses, such as the speeding-up of sewingunachines, the driving of velocipedes, the transmission of multiplied motion from the axle of a harvester to the cutter-bar shaft, the.

The cams shown in Figs. 1 tot} are two-throw cams and transmit double speed. If threethrow cams are used, the transmission will be to triple speed. Four throw cams will give a fourfold speed, and so on, any desired multiplication of speed being attained by suitably I03 forming the cams.

It is not essential that two cams and two :2 saaaas cranks be used, the only object of duplicating them being; to avoid dead-centers. If the driven shaft be provided with a fly-wheel, a single cam, connecting-bar, and crank will usually suffice; but even then twoar'e preferable.

I have herein referred to the shaft B as the driven shaft; but with the duplicate arrangement of cams and cranks shown in Fig. l the power may be applied to this shaft and transmitted at a reduced speed to the shaft A.

The cams G 0 maybe constructed in any way desired. Those shown consist of a disk cut through to form the slot 0, and the outer ring thus formed held in place by means of a diametrically-arranged bar, (1, formed prefer ably in one piece with the cam-disk. It is not essential, however, that the cam shall consist of a disk, as any form of cam having a cycloidal slot, groove, or other working-surface, acting in connection with a roller, connecting-rod, and crank, will come within my invention.

Fig.4 shows athree-throw cam for trans mitting motion at three times the speed of the driving-shaft. Nhen two cranks and two cams are used, the cams should be set one thirty degrees in advance of the other, with cranks set ninety degrees apart. This View also shows a modified means of guiding the roller e, a sliding block or head being arvranged at the end of the rod E, moving in a slideway, F. be used.

I claim as my invention" 1. The combination, as a mechanism for transmitting multiplied rotary motion, of a driving-shaft, a cam thereon having a cycloida1 slot or working-face, a roller engaged and Any other suitable guide may, 7 '1 equivalent working-face, two rollers engaged" and reciprocated by the respective cams, the driven shaft with two cranks thereon, one set a quarter-revolution in advance of the other, two connecting-rods, eachcommuuicating the motion of one of said rollers to the correspond. ing one of said cranks, and guides for said rollers restraining them to move in adirection toward and from the driven shaft, substantially as set forth. In witness whereof I have hereunto signed my name in the presence of two subscribing witnesses.

ALBERT D. JEFFREY.

W'itnessesz' ARTHUR G. FRASER, GEORGE H. FRASER.

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