US103698A - Daniel a - Google Patents

Description

dichiari I @states DANIEL A. WOODBURY, OF ROCHESTER, NEW YORK.

Letters Patent No. 103,698, elated Muy 3l, 1870.`

REVERSIN G- AND CUT-OFF APPARATUS FOR STEAM-ENGINES.

The Schedule referred to in these Letters Patent and making part of the same I, DANIEL A. WooDBUnx, of Rwhester,l in the county of Monroe and State of New York, -have in,-

v vented certain Improvements in Cut-oil? and Reversing-GearWor Steam-Engines, of which the following is a specification.

My invention consists chiedy in a novel mode of shifting the eccentric of a' steam-engine, whereby the valve may be made to work the engine in either direction, or to cut ofi` at-diifcrent points, or both.

In the drawing;

Figure l1 is a vertical central section of my invention.

Figures 2 and 3 are side elevations.

Figure 4 is a sectional ,elevation of those parts to the right of the dotted line x, tig. 1.

The main eccentric A is swung from a stud or gudgcon, a, which has a bearing in an arm, g, of the hub H, at a suitable distance from the center of the crankshaft S.

The collar H is adj usted at the proper point upon the shaft by the set-screw u, fig. 1, or an equivalent device.

The crank-shaft passes through a slotted opening in the eccentric A, (shown in fig. 3,) wherehythe latter is allowed a considerable lateral movement about the center which center, as will bc seen by reference to fig. 3, is'located in the line of ecccntricity of the cccentric. p

To control the lateral adjustment of this eccentric I provide an auxiliary eccentric, B, iigs. l and 4, iitted loosely to the crankshaft and revolving easily in a sliding-plate, C. l

The slideCworks between or upon lugs l), so fornicd upon one side of the main eccentric as to allow the slide a reciprocating motion nearly or quite in theline of the centers ofthe main eccentric and stud'a.

The object of the slide C is to provide an ample bearing for the auxiliary eccentric on the lugs l), but

it is not a necessary part of my invention.

It will thus be seen that, by revolving the auxiliary eccentric, the Ina-in eccentric is swung laterallynpon the stud a, and its throw correspondingly increased; while at the saine time the position of its center with relation to the crank K is changed, as indicated by dotted lines t and t', iig. 4.

rlhe stroke ofthe eccentric A, when at the central point of its adjustment, ismade about equal to the lap of the valve, and thehub H is so adjusted upon the shaft that the bearing for the stud a, and conscquently the heavy or stroke-side of the eccentric shall be opposite the crank K, as shown in g. 1, whereby the valve moves through only a short central portion of its travel, and neither port is uncovered, an act-ion similar to that caused by the well-known link when at "or near its center.

to increase the ccccntricity of Ato correspond with the full travel of the valve.

For convenience in operating the auxiliary eccentric, a friction-wheel J is fixed to it, upon the periphery of which a brake, M, is made to bear, when desired.

The bearingp of the stud a extends througlnthe wheel J, and the circumferential movement of the latter is limited by its arms ff coming in contact with said bearing, as shown in igs. 2 and 3.

The location voi' the arms f fis, snchthat said movement of the wheel and auxiliary eccentric is about one-half a revolution, which consequently swings the main eccentric A to thc extremity oi its adjustment either way; and this action is suicient to change it from the full backward'to the forward position, or vice rversa, as indicated bythe dotted circles p and 1)', iig. 4.

The blow upon the arms ff', when the motion of t-he wheel J is suddenly arrested, is relieved by the elastic cushions c, suit-ably attached to veach side of the bearing g, and it will be observed that, since the wheeland eccentric B have slightly more than one-half a revolution upon the crank-shaft, the auxiliary being on dead points with relation to the swing of the main eccentric A, a considerablel difference in the thickness of the cushions c will not be perceptible in the adjust-ment of the valve.

Upon one odge of the slide O I provide the checkbolt d, shown in section in fig. 4, turned conical upon the inner extremity so as to drop into corresponding countersinks in the periphery of the eccen-'l tric B. This bolt is fitted accurately to a hole bored through the edge of the slide, while its outer end is guided by a nut, e, screwed into or upon a boss formed upon the slide.

Between the nut and thehcad of the check-bolt a spiral spring, s, is located, by means of which the bolt is retained in cont-act with the eccentric.

Notches o are formed in the periphery ot' tixed colf I lar H, into which the latch L may be dropped when desired. The latch is secured to au arm ofthe wheel, J, and may be pivoted thereon, or arranged to slide between guides, and held in position by a bolt.

The brake M is hinged to a suitable portieri ofthe engine-bed, and is retained out of contact with the'. wheel J by spring I.

A cord may be attached to the brake-lever and carried to any desired point away from the engine.

The operation of my invention is as follows:

,When the crank K is moving in the direction ofthe arrow, fig. 4, the main eccentric 'is in the position indicated by the dotted circle p. 1f, however, the brake M is applied to the wheel J, the motion of thelatter ceases momentarily, while that of the crank-shaft and hub H continues till the arm f comes in contact with the arm y of the hub.

The auxiliary B is thus given about half a revolu tion, which swings the main eccentric over to the re- Vverse position indicated by'the dotted circle 11', time,

and dotted lines in fig.'3, and the engine is consequently caused to move in the opposite direction. lhe application of the brake again'reverses the main eccentric and the engine in a similar manner,

The check-bolt d operates to prevent the wheel J` creasing the travel of the valve and regulating itsy point ot -cutott`, the effect being similar to that caused by the use of the link and two eccentrics llhis adjustment may bcalso made by the check-boltd entering eonntersinks'in the periphery of the auxiliary eccentric, such recesses corresponding in relative position with the notches 0'. lhc stroke side ofthe eccentric A may be upon the opposite side of the crank-shaftom the center a, it' desirable, as its action will bethe same so long as the center c is in the line of eccentricity.

Instead ot' the auxiliary eccentric B I may use a link or combination of links, suitably pivoted to' the hub ofthe wheel J, and to the swinging eccentric A.

The valve may bc reversed when the engine is at rest, by turning the wheel J with the hand, in the proper direction It is obvious that my.invention is cheap and simple, and vnot likely to get outof order; that it combines a reversing-gear and variable cnt-off at only a fraction of the expense of the ordinary link motion, while, at the same time, it is more easily operated, and is capable of being reversed at any distance from the engine. f

What I claim as my invention isl. An eccentric, swung'upon a center outside of the crank-shaft, and having its lateral adjustment controlled by au auxiliary eccentric, or a similarly operating-device, for the purposes set forth.

2. lhe swinging eccentric A and auxiliary eccentric 13,. in combination with a suitable device for locking them at the extremity or any intermediate point ot' the lateral adjustment of the former, for the purposes specitied. f

3. The friction-wheel J attached' to the auxiliary eccentric B, Yin combination with the swinging-eccentric A, with or without the slide G, operating substantially as described. i

4. The elastic cushions c, iu combination with the fixedl hub H and stops the purposes set forth.

5. The adjustable yspring check d, in combination with the swinging eccentric A, or slide C, and auxil-l iary eccentric B, operating substantially as set forth. D. A. WOODBURY. Witnesses:

HENRY H. Peron, F. H. CLEMENT.

fand 'f' on the wheel J, for

Images