US1557982A - Exhaust-steam collector - Google Patents

Description

R. w. CNPF-ORD EXHAUST STEAM COLLECTOR Oct. 20

Filed Sept. 3, 1924 S E s S E N H W Patented Oct. 20, 1925.

UNITED STATES ROGER W. CLIFFORD, OF VSCHIENECTADY, NEW YORK.

EXHAUST-STEAM COLLECTOR.

Application filed September 3, 1924. Serial No. 735,593.

To all whom t may concern.

Be it known that I, ROGER W. CLIFFORD, a citizen of the United States, residing at Schenectady, in the county of Schenectady and State of New York, have invented a certain new and useful Improvement in Exhaust-Stean'i Collectors, of which improvement the following is a specification.

My invention relates to effecting the supply of exhaust steam from steam engines, to auxiliaries operated by exhaust steam, and its object is to provide means, of simple and inexpensive construction, and ready applicability in steam engines of present standard type, for collecting and delivering exhaust steam to an auxiliary, at a higher pressure than has been or is, attainablei'n present practica The improvement claimed is hereinafter fully set forth. f

Exhaust steam operated auxiliaries usually collect or receive theirsteain supply from a point in the exhaust pipe of the main engin-e, from which it is delivered, adjacent to the end of said pipe which is further from the engine cylinders, and as a result. the steam delivered to the auxiliary is reduced in pressure, by reason of being expanded in its traverse through the exhaust passages. In many cases, it is found that the supply of exhaust steam delivered, is insutiici-ent to operate the auxiliary or auxiliaries, and therefore, must be supplement-v ed by a supply of live steam from the boiler. An instance of this objection is, for ex` ample, found in the operation of a. steam' locomotive, equipped with an injector operated by' exhaust steam, the supply thereto being taken Vfrom the exhaust pipe near the nozzle. Under c-ertain ruiming conditions, the supply of exhaust steam obtainable is inadequate to operate the injector, by reason of its lov7 pressure, and live steam must be taken from the boiler. The advantages derivable from the use of exhaust steam are therefore only partially realized.

My invention is designed to overcome the objectionable result above noted, by rendering available a supply of exhaust steam at higher pressure, by a novel construction of steam distribution valve and accessories, which presents the further advantage of being applicable to existing engines, Without involving any structural modifications of cylinders and ports.

ln the accon'ipanying` drawing: Figure l is a vertical axial section through a cylinder and valve chest of a locomotive engine.. illustrating an embodiment of my invention; F ig. 2, a. partial section, on an enlarged scale, through one end of the steam distribution valve and the. adjoining bull ring; Fig. 3, a partial transverse section, on a similar scale, through the same, on the line lll-III, Fig. 2; and, Fig. 4l, a view, in elevation, of a check valve segment.

ln the practice of my invention, referring descriptively to' the specific embodiment thereof which is herein exemplified, as applied in connection with a locomotive cylinder, and its distribution valve chest, the cylinder. l, is of the ordinary standard type,

` fitted with a. piston, 2, secured upon a pisand communicates, by induction ton rod, 2, and eduction ports, l, adjacent to its ends, with a valve chest, 3, adapted toireceive a steam distribution valve, and to be supplied with steam from the boiler, through a` supply connection inlet, 3, at its top. The ex haust of steam is e'lected from the ends of the valve chest, through exhaust passages (not shown) ask in the ordinary operation of inside admission piston valves. y

'lhe distribution valve, which is of the inside admission piston type, comprisesa tubular main body, 4, which is secured, at its ends, to two tubular followers, 4, Which are connected by arins,'ld, to central hubs, le, secured, at a proper distance apart, upon a valve stein, 5, by a nut, 5, so as to be moved coincidently by said stein, andI prevented from turning therein'. Thel followers are machined to make steam tight joints With bull rings, 4b, fitted withpacking rings, 4", of the ordinary type, said bull rings reciprocating, withv the distribution valve, in bushings, 3c, fixed in the valve chest, and having peripheral ports, 3d, which `arecontinuously in communication with the `induction andA cduction ports, la, of the cylinder, 1.

A plurality of ports, lle, is formed, in a `single transverse plane, in each of the followers, l, of the distribution valve, said ports being yseparated by bridges, 4f, 4g, which connect the adjoining portions of the followers together, the bridges, 4g, being wider than the bridges, 4f, and acting as guides for a plurality of segmental sections, in the forni of thin metallic plates, constituting check valves, G, which surround the ports, 4G, and are interposed between the followers, 4, and the bull ring, 4". The bull rings are fitted with packing rings, 4h, of the ordinary type, but differ from those of the usual construction, in being provided with a row of ports, 4i, passing through them, separated by thin bridge walls, 4j, which extend to a circumferential bridge, 4k, at the inner ends of the ports, 4i, which divides the single outer row of said ports into a double row of inner ports. The circumferential bridges, 4k, are machined, to form steam tight joints with the sections of the check valves, 6, and the bull rings are grooved to form seats therefor. lVhere the ends of the check valve sections adjoin, outwardly turned extensions, 4, are formed, on the bridge, 4k, to provide surfaces for the movement of the ends of the sections, and also to provide space for a stop, such as a dowel, if preferred.

The sections of the check valves, 6, are thin, fiexible metallic plates, bent into segmental form, and somewhat longer and wider than the ports against which they close, in order that steam tight joints may be formed entirely around the edges of all the port openings against which they seat.

Gaskets or rings of suitable packing material may, if desired, be interposed between the fianges of the body, 4, of the distribution valve Land the followers, and squeezed to form tight joints, when the valve is assembled by tightening the nut, 5a, on the valve stein, and thereby drawing the followers towards each other.

The front end of the valve chest, 3, is closed by a head or cover, 8, having an inwardly projecting tubular extension, 8a, communi.- cating with a pipe, 9, connected to the head, through which exhaust steam from the cylinder is delivered to the auxiliary which is to be supplied. The rear end of the valve chest is closed by a head, lO, having an inwardly projecting tubular extension, l0, similar to the extension, 8a, of the front head. The ports, 4e, of the followers, 4, are controlled by stationary valve structures connected to the extensions, 8a, and 10, of the heads. The valve structure of the front head comprises a bull ring, 8b, packing rings, 8,A and follower, Sd, secured to the extension. A. similar valve structure is provided on the tubular extension, 10a, of the rear head, which head carries a suitable stufling box, the distribution valve reciprocating over the bull rings and packing rings of the two structures.

The reciprocating movements ofthe steam distribution valve, which are imparted to it by a valve gear of any suitable and preferred construction, connected to the valve stem, 5, effect precisely the same events in the lcylinders of engines in which my invention is applied as in those not equipped with it, that is to say, the orderly and appropriate disposition of the points of admission, cut ofi, release, and closure, but it will further be seen that, in the operation of engines on which it is applied, when the distribution valve has reached the point of release, and is just about to permit steam in the end of the cylinder to pass out through the exhaust port, the ports, 4e, in the valve follower, are also just about to open, which will permit some exhaust steam to pass into the inside of the distribution valve, from which it will pass out through the pipe connection in the valve chest front head. The opening of the ports, 4", relatively to the point of release in the distribution valve travel, can be readily determined by experiment, and the proper adjustment of the distribution valve be made to produce the best results. The ports, 4e, will remain open until the valve has travelled sufficiently far to close the ports, 4i, but inasmuch as this point is reached before the end of the piston travel, the exhaust steam collected will be of a higher pressure than if it had had time to fall to the normal back pressure level, exemplifying the substantial advantage of the invention in trapping the exhaust steam at a higher pressure than is attainable under prior practice.

On the return travel vof the distribution valve, there would be a reflux of exhaust steam from the inside of the main valve, through the ports, 4", and 4i, into the exhaust passages of the cylinder, except for the operation of the check valves, 6, which are applied solely to prevent such reflux. The action of said valves will be readily understood, as when the pressure in the cylinder admission and exhaust ports, l, is higher than on the inside of the distribution valve. the check valves are raised off their seats in the bull rings, 4b, until they strike the bridge, 4f, of the valve follower, thereby permitting the passage of some exhaust steam, but in the reverse condition, that is, when pressure in the tubular body of the distribution valve is higher than in the cylinder exhaust ports, the check valve sectlons are deiiected out-wardly against their circular seat on the inside of the bull ring, 4b.

I claim as my invention and desire to secure by Letters Patent:

l. In a reciprocating steam engine, the combination of a steam cylinder; a tubular piston distribution valve, communicating, by induction and education, ports therewith;

a valve chest, in which said valve is fitted y to reciprocate; bull rings, fitted in the distribution valve and having ports adapted to communicate with the cylinder ports; and stationary valve members, fixed in the valve chest and controlling the ports of the bull rings.

2. In a reciprocating Steam engine, the

combination of a steam cylinder; a tubular piston distribution valve, communicating, by induction and eduction ports, therewith; a valve chest, in which said valve fitted to reciprocate; bull rings, fitted in the distribution valve and having ports adapted to communicate With the cylinder ports; stationary valve members, fixed in the valve chest and controlling the ports of the bull rings; and check valves, preventing reflux of exhaust steam through said bull ring` ports, by eiecting their closure when uncovered by passage beyond the stationary valve members.

3. In a reciprocating steam engine` the combination of a steam cylinder; a tubular piston distribution valve, communicating, by induction and eduction ports, there- With; a valve chest, in which said valve is itted to reciprocate; heads, closing the ends of said chest and having tubular extensions on which the distribution valve is fitted to reciprocate; bull rings, iitted in the distribution valve and having ports adapted t0 establish communication between the cylinder ports and the space Within the distribution valve; and check valves, each comprising a plurality of segmentally curved sections and controlling the ports of one of the bull rings.

ROGER W. CLIFFORD.

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