THE MOORE.
The valve for admitting steam to and exhausting it from the cylinder of this pump is contained within the cylinder and moves simultaneously with the steam piston, having no outside mechanism. SeeFig. 278.
The piston, and also the valve, are of the form of spools, each representing a hollow sleeve with a ring packed piston head at either end. The piston is secured to the piston rod and the sleeve connecting the two heads serves as the valve seat for the cylindrical valve. The sleeve of the piston contains two longitudinal ports, one port communicating with one end of the cylinder, and the other port communicating with the opposite end. Suitable holes drilled through the walls of the sleeve and communicating with the longitudinal ports, act as admission and exhaust ports, with which the holes and cavities in the sleeve coincide at proper positions in the stroke.
Referring to the accompanying engraving,Fig. 279, which represents the valve and piston in the position occupied when ready to commence a stroke from left to right, the reader will easily understand the action of these parts. When the piston reaches the end of the stroke steam enters through the steam pipe at A, between the pistons, and forces the valve to the left as shown. This movement opens the port, B, and also brings the cavity, C, in communication with port, D, steam being admitted through ports, B and D, into the longitudinal port, F, thence into the clearance, G, of the cylinder. This causes the piston to move toward the right. When the piston has moved a short distance to the right steam is admitted into the space, H, surrounding the valve, and passing into the cavity, C, and through the port, D, furnishes steam to complete the stroke.
Should the piston stop at mid-stroke it will start again as soon as steam is turned on, because the port, D, remains open until the valve is reversed at the opposite end of the stroke.
When the piston reaches the latter position,Fig. 280, the valve is reversed, due to steam entering at A, and again forcing the pistons apart, as shown. The steam, which drove thepiston from left to right, now escapes through the port, I, into the cavity, J, and around the sleeve to the holes, K,Fig. 279, where it enters the hollow piston, and finally escapes through the hollow rod, L, and the port, M. The live steam for the next stroke from right to left, now enters through ports, N and O, Fig. 280, and flows through the longitudinal port, P, into the end, Q, of the cylinder.
Fig. 279.
Fig. 279.
Fig. 280.
Fig. 280.
The exhaust steam may be allowed to flow into the atmosphere or into the suction chamber as desired. A valve islocated in the base of the pump, which changes the course of the steam from the atmospheric discharge to the suction chamber. The valve is operated by a lever shown by dotted lines. When the lever is turned down toward the steam end, the steam is directed into the atmospheric exhaust, and when turned in the opposite direction the steam will enter the pump suction and be condensed.
There is no valve setting to be done on this pump.Should the pump fail to work properly, due to the failure of the steam end, all that is necessary is to take out the valve and piston and clean them thoroughly and after replacing them and starting the pump to see that these parts are properly lubricated. The remainder of the pump requires the same care and attention that is, or should be, given all pumps.