US641132A

US641132A - Slide-valve.

Info

Publication number: US641132A
Application number: US71198199A
Authority: US
Inventors: Ila N Moore
Original assignee: Individual
Current assignee: Individual
Priority date: 1899-04-06
Filing date: 1899-04-06
Publication date: 1900-01-09
Anticipated expiration: 1917-01-09

Description

No. 64!,l32. Patented Ian. 9, I900.

I. N. MOORE.

SLIDE VALVE.

(Applicatiun filed Apr. 6, 1899.) I

(No Model.)

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ILA N. MOORE, OF BATTLE CREEK, MICHIGAN.

8 LI DE-VALVE.

SPECIFICATION forming part of Letters Patent No. 641,132, dated January 9, 1900. Application filed April 6, 1899. Serial No. 711,981- (No model.)

To all whom it may concern:

Be it known that I, ILA N. MOORE, of Battle Creek, in the county of Calhoun and State of Michigan, have invented a new and Improved Slide-Valve, of which the following is a full, clear, and exact description.

The invention relates to slide-valves for steam-engines, steam-pumps, and. motors; and its object is to provide a new and improved slide-valve which is simple and durable in construction and arranged to admit a uniform amount of steam to the cylinder, irrespective of a short or long stroke of the slide-valve, to insure uniform work of the engine.

The invention consists of novel features and parts and combinations of the same, as

' will be fully described hereinafter and then pointed out in the claims.

A practical embodiment of my invention is represented in the accompanying drawings, forming a part of this specification, in which similar characters of reference indicate corresponding parts in both the views.

Figure l is a longitudinal sectional side elevation of the improvement, and Fig. 2 is a plan view of theValVe.

In steam-pumps as heretofore constructed it is frequently observed that when the pump does heavy work the piston travel and that of the valve are shorter than when the pump is doing light work. For instance, if the pump is used for supplying the boiler with the feed-water and the discharge of the pump is changed from the boiler, say, to an open tank then the pump with the same set of throttle will immediately change to a longer stroke, both with the piston and the admission, than the one it had during the time the feed-water was pumped into the boiler against boiler-pressure. Thus, owing to the shorter travel of the valve, less steam is admitted under a heavy load-that is, at the very time when more steam should be admitted-and when the load is reduced the stroke increases, and the valve consequently admits more steam, causing the piston steam to hammer and pound unless the throttle is reset by the engineer to admit less steam. In order to overcome this difficulty and assure of admitting a uniform amount of steam to the cylinder under the various conditions of the valve, es=

pccially when the pump is doing variable work, I provide the improvements presently to be described in detail.

As shown in Fig. 1, theimprovement is applied to a steam pump having the usual steamcylinder A, in which reciprocates a piston 13, connected by a piston-rod G with the plunger in the pump cylinder. (Not shown.) The steam-cylinder A is provided with the usual admission-ports a and. b and the exhaust-port c, and the said ports are controlled by a slide-valve D, held to move in a steam-chest E, connected with a suitable source of steamsupply. The slide-valve D is controlled by The usual piston F, fitted to slide in the steam-chest E and shifted automatically from one side to the other by steam admitted to the ends of the piston through ports controlled by an auxiliary slide-valve G, having its stem II operated by a rockerarm I, actuated from the piston-rod O. The construction of the valve Gand the piston F, carrying the slide valve D, is of the ordinary kind, so that further description of the same is not deemed necessary.

The wings D D of the slide-valve D are made sufficiently long to keep the admissionports a and bi covered when the slide-valve is at the ends of its stroke, and in said wings are arranged ports e and f, adapted to register with the admission-ports a and 5, respectively, said ports 6 and f being located on the wings at such points that they register with the corresponding ports a and 5 during both a long and short stroke-of the valve D, so that a uniform amount of steam is admitted to the cylinder A during either a long or a short stroke of the slide-valve D. As shown, the ports e on one wing are larger than those f on the other wing, (or to secure the same function the ports might be alike in size, but different in number.) The passage area is thus different for one wing from the other. This construction is of advantage when, as often is the case, the piston B has work to do only going one way, the larger passage area of one wing of the slide-valve supplying the required larger quantity of steam for the working stroke, while the passage of the other wing, being of reduced area, admits only steam enough to return the piston B during the inactive stroke.

As shown in Fig. 1, the portsfare in register with the admission-ports I), while the port a is connected by the slide-valve d with the exhaust-port c, and steam can pass from the steam-chest E by way of the registering portsfandb to the inner end of the cylinder A to move the piston 13 to the left to finally reach the position shown in said Fig. 1. During the travel of the piston B to this position the piston-rod O actuat-es the rocker-arm I and shifts the stem H and the valve Gto the position shown in dotted lines, so that the valve G uncovers the port leading from the steam-chest E to the left-hand end of the piston F, and-the latter is now shifted to the right to carry the slide-valve D in the same directionthat is, to move the ports f out of register with the port I) and to move the ports 6 in register with the port a. Steam now passes from the steam-chest E to the left-hand end of the cylinder A to move the piston 13 to the right on the return stroke. from the foregoing that in either case the ports a andf register with the ports (t and b, which are considerably wider than the diameters of the ports e and f, and consequently a uniform amount of steam is admitted to the ends of the cylinder irrespective of the long or short stroke of the valve D.

It is well known that in ordinary slidevalves the wings are short enough to open the ports a and Z) full width when making a full-length stroke and only open a small portion of said ports when .doing heavy duty on the short stroke.

Although the improvement is shown as applied to a valve moved by a piston, it is evi- It is evident dent that other means for shifting the valve may be used-for in'stance,the valve-stem and outside connectionsto give the ordinary sliding motion to the valve.

It is understood that in actual practice the speed of a steam-pump is retarded when doing heavy work, (boiler-feeding) and when with my improvement the desired speed is given to the pump by selecting the number and size of the ports 6 andfaccordingly it is evident that the valve will fully answer the purpose when the pump is doing light work that is, filling a tank.

Having thus fully described my invention, I claim as new and desire to secure by Letters Patent 1. The combination with the cylinder having suitable ports, of a slide-valve having through-ports of less diameter than the cylinder-ports and adapted to register therewith, the ports at one end of the valve being of a different area from those at the other end, and means for operating the valve.

2. A slide-valve, provided with extended wings for covering, at all times, the admission-ports to the cylinder, said wings being provided with ports adapted to register with the admission-ports on either a short or a long stroke of the valve, the ports on one of the wings being of a different area from those on the other wing, substantially as shown and described.

ILA N. MOORE.

Witnesses:

N. Y. GREEN, J. W. WILKINS.