US315270A

US315270A - Heevey w

Info

Publication number: US315270A
Authority: US
Publication date: 1885-04-07
Anticipated expiration: 1902-04-07

Description

EL'W. EOWLER- (No Model.)

CAM.

No. 315,270. Patented Apr. 7, 1885.

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' UNITED STATES f PATENT OFFICEO HERVEY W. FOWLER, OF CHICAGO, ILLINOIS.

CAM.

SPECIFICATION forming part of Letters Patent No. 315,270, dated April I, 1885.

Application filed June 28, 1884. (No model.) V

i To all whom it may, concern.- 7

Be it known that l gitnnvny W. FOWLER, of Chicago, in the county of Cook and State of Illinois, haveinvented certain new and useful of cams are peculiarly liable to abrasion, be'.

cause they are in constant frictional contact with surfaces of such devices as rely upon the cams for motion, and it is as well known that I the actual labor performed by different portions of a cam varies according to circumstances, and that usually the greatest strain upon a cam is while causinga device to be moved in one direction only, the return movement involving no force other than may be requisite for overcoming the friction between the reciprocating device and its guide-bearings, and so frequently is this true that mere springs or weights arefrequently relied upon for effecting the said return movement. It has heretofore been proposed to overcome said objectionable frictioualabrasion,and the consequent waste or loss of power, by the use of friction-rollers, applied to the device which is reciprooated by a cam; but I have, as I believe, for the first time provided in the cam itself for operative cam-surfaces which have a movement independently of the cam itself, which also has operative cam-surfaces which have the usual movement or operative capacity, as

is usual in cams, thus enabling a cam to perform its light work by means of those surfaces which move with the cam and its heavy work by means of its surfaces which are capable of independent movement.

I am aware that in eccentrics as heretofore constructed friction disks or rollers have been employed to afford a continuous rolling contact with the interior of the usual eccentric strap or ring, and it is to be distinctly understood that my present improvements are not applicable to eccentrics, but are limited to cams, which not only embody operative surfaces which operate as in ordinary cams, but, in addition thereto,surfaces which are capable of movement independently of the remaining portion of the cam.

To more particularly describe my inventionf I will refer to the accompanying drawings, in

Figures 1 and 2 in plan and horizontal seceating movements of a rod or bar at each revolution. Figs. 3 and 4 illustrate in plan and edge view a stationary cam embodying my improvements as employed with a revolving cylinder provided with a series of radially-re ciprocating rods orbars. Figs. 5 and 6 illustrate in edge view and section a pair of coin- 6 5 cident cam-wheels affording a cam-groove be tween them in a manner well known, but embodying my improvements. jlustrate in side and edge viewa cam embody-l ing my improvements as employed for lifting o a rod or'ibar for the performance of heavy work.

cam.

Figs. 7 and 8 il- Fig. 9 is a modification of my improved It is to be understood that my improvements can be applied to cams of many varieties, and that it would be impraiticable to illustrate all of them; but it is believed that a description of the several types shown in the drawings will render it easy for ordinary persons to apply said improvements to any cams wherein they would seem to have special value.

In Figs. 1 and ,2 the cam A isa grooved wheel-cam having a continuous cam-groove, A, so shaped as to impart at every revolution. of the cam-shaft four complete reciprocating 8 movements to the sliding bar B. In this case it will be assumed that it is duringthe thrusting movements of the said bar that the he a yy work of the cam is to be performed, and that the return movements of said bar involve no 0 labor by the cam other than to overcome the frictional contact of said bar with its bearings. With said cam revolving in the direction indicated by the arrow, it is obvious that the return movements of the bar B will be,

caused by the sliding frictional contact of a toe-piece on said bar and the outer surfaces, of the cam-groove at four different points therein, (indicated ata in each instance.) It will also be obvious that the thrusting move- I ment of said barB will be caused by its con tact with the inner surfaces of said camgroove at four intermediate points, (indicated at b in each instance.) Instead of having 'tion illustrate a revolving cam embodying my invention capable of inducing four reciprothese intermediate thrusting points of con tact integral with the cam itself, or, in other words, a surface with which said bar will en gage in frictional sliding contact as with the opposite or outer side of said cam-groove, I have for the first time as I believe, provided such cams with a cam surface which is capable of moving independently of the cam, so that when it engages the reciprocating bar by the rotation of the cam it commences to move in a direction opposite to that in which the provided with a series of radially-reciprocating plungers, d. In this case it will be assumed that said plungers are to be forced outwardly under great resistance from one side of the roll as it revolves, and to be merely retracted during the remainder of the revolution of said roll. The cam-groove B, at b, with its inner surface, projects said plungers, and at a, with its outer surface, it retracts them, while at 6 said groove permits them to rest. With this cam the hard-working inner camsurface, b, is afforded by the disk 0, which has its axis located at one side of the axis of the cam, and conseqently its working-surface is eccentric to the axis of the revolving roll.

In Figs. 5 and 6 the cam-groove D is afforded by the two coincident revolving camwheels D in a manner well known,their function being to laterally vibrate a rod or bar,E, provided,as is common,with a friction-roller, E. In this case b in each instance denotes the heavily-worked cam-surfaces, and in each case they are afforded by about one-quarter of the periphery of a rotative disk, 0, as already described. In this connection it will be seen that a friction-roller can be ad antageously employed on the reciprocating device in con neetion-with my improvements, and with much less shock or jar than if said friction-roller E was directly engaged by cam-surfaces which were capable of no movement other than in the direction in which the cams are rotated.

In Figs. 7 and 8 the cam F, revolving in the direction of the arrow, is organized to lift a rod or bar, F, in the performance of heavy work, and to permit it to fall either by its own weight or to be actuated by an expansive spring, as shown, so as to cause said bar at its foot to ride in contact with the retreating and resting surfaces of the cam. In this case 1) denotes the heavily-worked surface of the cam, a the retreating surface, and e the resting surface. The revolving disk 0 is, as in the other instances described, mounted on the cam and operates in the same manner.

It is not to be understood that a disk will be required in all cases, it being obvious that a section of a disk or a quadrant can be some times employed, and in some cases a pivoted arm can be relied upon, as illustrated in Fig. 9. In this case the cam G has the surface a for retreating the bar G and the pivoted arm f for engagement with the heel of said bar during its thrusting movement. This arm f is pivoted to said cam at one side of its axis, and is provided with a retractile spring for maintaining it in its inactive or normal position. As the cam revolves, the heel of the bar engages with the outer end of said arm, which then swings, carrying said bar farther away from the axis of the cam, until, by the further rotation of the cam,the bar is disengaged from the arm, which then flies back, ready to repeat the same service when it next again reaches the bar. This type of my invention is obviously only available when slow speed is involved. It will be seen in each instance of the forms of cam illustrated that from the moment the independently-movable cam-sur face engages with or is engaged by the heel of the reciprocating device the latter is projected substantially as if it were operated by a toggle-lever, thus enabling the cam to perform heavy service with a minimum of power and without destructive abrasion.

While my improvements have value in various types of cams, they are of special consequence in connection with such cam-wheels and disks as have continuous cam-grooves, and therefore I make special claim thereto.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- 1. A cam provided with ordinary workingsurfaces and also with working-surfaces capable of movement independently of the move ment of the cam, substantially as described.

2. A grooved cam wheel or disk having portions of the working-surfaces of its cam-groove composed of the peripheral surfaces of one or more disks rotatively mounted on said wheel at points more or less removed from the axis thereof, substantially as described.

HERVEY V. FOWLER.

\Vitnesses:

PHILIP F. LARNER, HOWELL BARTLE.

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