US241585A - Pabdotf aemington - Google Patents

Description

( Model.)

P. ARMINGTON, Steam Engine Governor. No. 241,585. Patented May 17,1881.

N. PETERS, Pholo-Lithngnphar. war-mm". v.0.

UNITED STATES PATENT OFFIC STEAM-ENGINE GOVERNOR.

srncrnrcatrrolv forming part of Letters Patent No. 241,585, dated Ma 17, 1881.

Application filed March 23,1881. (No model.)

To cltwhom it may concern:

Be it known that I, PAeDoN ARMINGTON, of Lawrence, countyot' Essex, State of Massachusetts, have invented a new and useful Improvement in Steam-Engine Governors, of which the following description, in connection with the accompanying drawings, is a specitication.

My invention relates to steam-engine governors of that class in which the valve-operating eccentric is moved relative toits shaft by centrifugally-acting weights,to thereby vary the throw of the valve, and thus govern the admission of steam to the cylinder to control the engine. I I

In the governors of this class, as heretofore constructed, the eccentric being made movable relative to the shaft the valve will sometimes react on the said eccentric, throwing it from the position it would normally occupy under the influenceof thegoverning-weights, and thuscause the engine to act improperly.

My invention has for one of its objects toobviate this difficulty; and it consists in so connecting the governing-weights and the eccentric that the former readily acts on the latter to move it, but the weights cannot be moved by force applied to the eccentric bythe reaction of the valve or otherwise.

The eccentric is shown as mounted on a carriage arranged to move in suitable guides on the outside of the case containing the governor-weights, springs,-&c., mounted on the main shaft of the engine in the. usual manner, the eccentric being thus free to travel in a straight line at right angles to the main shaft, to vary its eccentricity and the consequent throw of the valve.

The governing-weights, (shown as two. in number,) pivoted at opposite sides of the case and symmetrical relative to the main shaft, are connected by a link, to equalize their action, and springs are interposed between a suitablyheaded link connected with each of the said weights and an abutment upon the case in such 7 manner that the said springs are compressed as the weights are thrown outward by cen trifugal force, instead of being stretched in the usual manner, the springs when acted on by compression retaining their force much more uniform'than when under tension. One of the said weights is provided with a cam-like portion, shown as a curved rib projecting from one face of the said weight and engaging the co centric-carriage by means of a suitable block, in which the said projecting rib fits, and as the weight moves on its pivot under the varying action of centrifugal force, the position of the portion of the cam-projection that engages the eccentric-carriage is varied relative to the axis of the main shaft, so that it causes the carria-ge and connected eccentric to move, as desired, to control the engine. The angle between ,the acting face of this cam and the line of movement of the eccentric-carriage is so nearly a right angle that according to the wellknown laws of friction a force applied to the carriage in acting on the said cam will not be able to move it, so that the cam effectually locks the carriage and eccentric in whatever position it has placed it. The eccentric-carriage is provided with two projections at its side, to receive between them the lever-a1 m of a counterbalancing-weight, by which the weigh t of the eccentric, its carriage, and connected parts operated thereby may be balanced in all positions. V

.Figure 1 is a face view of the inclosingcase and the weights and springs therein, the weights being shown in their extreme outward position; Fig. 2, a view of the opposite side of the case, and the eccentric and its carriage and counterbalancing-weight thereon, in the position assumed when the governing-weights are in their extreme inward position, as shown in dotted lines, the other extreme position of the eccentricbeing shown by the dotted circle; and v Fig. 3 a cross-section on the line as 00, Fig. 1.

Thecase a, having a hub, b, adapted to be fixed upon the main shaft 0 of the engine, is provided with suitable bearings at 2 3, for the pivots of the governing-weights d c, shaped as shown, to fit in the case a and swing back and forth between its hub b and peripheral rim under the action of centrifugal force as the speed of rotation varies. The weights (1 c are connected by a link, f, pivoted to them at equal distances from their pivoted bearin gs 2 3 in the case, and are thus caused to move equally, the action of gravity on one weight balancing its action on the other,it tending to move the two weights in an opposite direction relative to the hub of the case. The weights d e are provided with lugs g, in which are pivoted links h, provided with bearing heads or washers t, to receive the pressure of one end of the springs j surrounding the said links, and bearingat their other ends on suitable abutments, k, projecting from the hub b, and provided with apocket to receive the said spring and a hole or passage, 4, through which the lugs g and links it pass. By this arrangement the springs j are compressed as the weights (1 0 move out from the center of the ease, and the weights will come to rest when the centrifugal force and the opposing elastic force of the springs are in equilibrium, the springs being more compressed the higher the speed of the shaft 0, and consequent greater centrifugal foice of the weights d c. The force of the springs j can be adjusted by the nuts t" to regulate their action, and thus control the speed of the engine. The weights d e are recessed to pass beneath the springs j and their abutments k, and by this recessing two fingers, d e, are formed, each of which passes beneath the other weight, when the weights are nearest the hub I), as indicated by dotted lines, Fig. 2. One of these fingers, as d, is provided with the eccentric-operating cam, shown as a segmental rib, Z, projecting from the face of the finger opposite to the spring j, and engaging a slot in a circular block, m, fitted in a suitable socket in a projecting boss, at, from the carriage 0, sustaining the eccentricp, and mounted in guides r on the face of the case at, opposite to that containing the weights d e, the boss npassingthrough a suitable opening, 5, in the said ca e.

The eccentric and its carriage are suitably slotted, as shown at 6, to enable them to be moved transversely to the shaft. The eccentricp is mounted on the carriage 0, with its center at a distance from a line passin g through the axis of the main shaft 0 parallel totheline of movement of the said carriage sufficient to give the valve its least throw when the center of the eccentric is brought nearest to that of the shaft by the movement of the carriage, which takes place when the weights are thrown to their extreme outward position, as shown in Fig. 1, this throw being just sufficient to maintain the lead of the valve.

When the weights move inward toward the position shown in dotted lines the cam l, not moving concentrically with the axis of the shaft 0 as it passes through the slotted block m, causes the said block to move toward the center of the shaft, and thus cause the connected carriage 0 to move in its guides r and carry the eccentric toward the position shown in full lines, Fig. 2, increasing its throw in this movement, and thus controlling the valve and engine in the usual manner.

The carriage 0 is provided with two projections, 8 s, at one side and within one of the guides r, which is discontinuous, leaving a space for the said projections, and forming therewith a stop for the carriage at the end of its movement in either direction, the weights (1 0 being then stopped by engaging the hub I) or peripheral rim of the case a. The projectionsss on the carriageo receive between them the rounded bearing end of the lever t, pivoted at 7 on the case a, and provided with the weight w to counterbalance the weight of the eccentric and carriage.

The cam l is so constructed thatits bearingface is always nearly normal, or at right angles to the line of movement of-the carriage 0 in its guides r, so that aforce applied to the said carriage will be resisted by and powerless to move the said cam, which will place and retain the said carriage and eccentric in a position dependent on the position assumed by the weights (1 0 when in equilibrium between the action of centrifugal force and that of the springs j.

I claim 1. In-a governor for steam-engines, the case fixed upon the main shaft and govern or-weights pivoted therein, combined with the movable eccentric and its operating-cam attached to and actuated by one of the said weights, as described, to impart a positive movement to the eccentric and lock it in position when thus moved, substantially as set forth. 7

2. The governorcase provided with springabutinents and the weights pivoted therein, combined with the links, and their bearingheads connected with the said weights, andthe springs interposed between the said bearing heads and abutments, whereby the said springs are enabled to act under compression, substantially as and for the purpose set forth.

3. The governor-caseand weight pivoted therein, and provided with a cam-rib, combined with the eccentric and its carriage, and guides therefor mounted on the said case, the said earriage being provided with a bearing-block for the said cam, whereby the weight in its movement causes the eccentric and its carriage to travel in the guides, substantial] y as described.

4.. The eccentric and its carriage provided with lateral projections,'combined with the guides for the said carriage, and the weighted lever having a bearing-arm to enter between the said projections, whereby the weight of'the eccentric, its carriage, and parts controlled thereby is counterbalanced and its movement limited, substantially as described.

5. The governor-case and weigh ts and springs therein, the said weights being connected together by a link, and one of them provided with a cam-rib, combined with the eccentric and its carriage provided with a boss and the bearing-blockfitted in the said boss and slotted to receive the cam-rib, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

PARDON ARMINGTON.

Witnesses t J os. P. LIVERMORE, BERNICE J .N OYES.

Images