Fig. 22. The Monarch Engine with Corliss Valve Gear.—A, Rod to Eccentric; B, Governor;
C, Reach Rod; D, Radial Arm; E, Steam Valve; F, Bell-crank; G, Wrist Plate;
H, Exhaust Valve; K, Dash-pot
Side and sectional views of different forms of this type of valve are shown in [Fig. 19]. They are operated by means of short crank-arms which are attached to a wrist-plate by means of radial arms or rods, as shown in [Fig. 22]. The wrist-plate, in turn, is given a partial backward and forward rotation by means of an eccentric attached to the main shaft and connected to the upper part of the wrist-plate by a rod as indicated. The exhaust valves are both opened and closed by the action of the wrist-plate and connecting rods. The steam valves are opened in this manner, but are closed by the suction of dash pots attached to the drop levers on the valve stems by means of vertical rods, as shown.
Figs. 23 to 26. Action of Corliss Valve Gear
The action of the steam or admission valves is best explained by reference to [Figs. 23 to 26]. Referring to [Fig. 23], A is a bell-crank which turns loosely upon the valve stem V. The lower left-hand extension of A carries the grab hook H, while the upper extension is connected with the wrist-plate as indicated. Ordinarily the hook H is pressed inward by the spring S, so that the longer arm of the hook is always pressed against the knock-off cam C. The cam C also turns upon the valve stem V and is connected with the governor by means of a reach rod as indicated in [Fig. 23] and shown in [Fig. 22]. The drop lever B is keyed to the valve stem V, and is connected with the dash pot by a rod as indicated by the dotted line. This is also shown in [Fig. 22]. The end of the drop lever carries a steel block (shown shaded in [Fig. 23]), which engages with the grab hook H.
Fig. 27. Governor for Corliss Engine