US1112489A

US1112489A - Steam-engine.

Info

Publication number: US1112489A
Application number: US75752813A
Authority: US
Inventors: Robert C Stevens
Original assignee: Skinner Engine Co
Current assignee: Skinner Engine Co
Priority date: 1913-03-29
Filing date: 1913-03-29
Publication date: 1914-10-06
Anticipated expiration: 1931-10-06

Description

R. C. STEVENS.

STEAM ENGINE.

APPLICATION FILED MAR. 29, 15H3.

Patented 0013.6, 1914.

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R. C. STEVENS.

STEAM ENGINE.

- APPLIOATION ILED MAR.29, 1913.

' Patented Oct. 6, 1914.

'UNITED STATES PATENT OFFICE.

ROBERT c. sTEvENs, OE'ERIE, PENNSYLVANIA, AsseNoR To sxINNER' ENGINE CoM- PANY, OF ERIE, PENNSYLVANIA,

A CORPORATION OF PENNSYLVANIA.

' STEAM-ENGINE. l

T0 all 'whom 'it may concern Be it known that I, ROBERT C. STEVENS, a citizen of the United States, residing at Erie, in the county of Erie andl State of Pennsylvania, have invented certain .new and useful Improvements in Steam-Engines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will kenable others skllled in the art to which it appertains tomake and use the same, reference being had t0 the accompanying drawings, and to the letters of reference marked thereon, formlng part of this specification. y

My invention relates to steam-engines of the type known as central exhaust engine,

and has for its object the provision of an I exhaust valve in the pist-on body, which is adapted to open` when the central exhaust ports have been uncovered by the piston and to be automatically closed by reason of the compression accumulating behind `the p1ston upon its return stroke, when said piston has traveled a certain po-rtionvof said return stroke. I l

The features of my invention are hereinafter set forth and explained and are illustrated in the accompanying drawings in which:-

Figure 1, is a longitudinal section` on `the line .fr-m in Fig. 2, looking in the directlon of the arrow e, of an engine cylinder and piston embodying my invention. Fig. 2, 1s a transverse section thereof, on the llne g/-y, in Fig. l looking in the direction of the arrow in Fig. l. Fig. 3, is a longitudinal section of the cylinder and a section of the piston, on the/line 2 2, in Fig. 2, looking 1n the direction of the arrow lw, in Fig. 2. Fig. Il, is a longitudinal section showing analternative construction of my invention. Fig. 5, is a view in central horizontal section of Fig. 2, of the engine cylinder showing the engine piston in elevation therein looking upward at the inside thereof.

In these drawings, A, indicates an engine cylinder having central exhaust ports, B.

C, indicates a piston in said cylinder: C, indicates a piston-rod. Within the piston C, I place removable sleeves D, which sleeves are divided by the transverse wall nl; upon which wall, CZ, there is a valve-stem support d. The sleeves D, have an outturned flange (Z2, on one end thereof, which Specification of Letters Patent.

.closed position until engage an annular shoulder d3, in the body of the piston (l. The sleeves D, are secured 1n place in the piston C, by means of screw plugs D', which also close oney end ofv said sleeves D; the other end of the sleeves D, are closed by means of a puppetvalve E, which has a valve-stein E, mounted in and supported by the valve-stem support d, hereinbefore described. Secured upon the end of the valve-stem E', are pistons F, which preferably operate in the sleeves D, between the transverse division wall al, and theA plugs D. Between the division walls d, and the valves E, I place Asprings G, which normally maintain the valves E, in an open position.

Leading inwardly from the end of the piston C, there is a steam passage H, see

Fig. 3), whichterminates in the small pis- 'ton chamber formed by thesleeve D, and

the division wall (l, and the plug D, through which passage compressed air in the cylinder A, and steam may'enter into said small piston chamber and operate upon the small piston F, therein, to close the valve E, and maintain said valve E, in a l the pressure in the cylinder A, is relieved by the uncovering of the central exhaust ports B, by the piston C. In the side of the piston C, I make segmental recesses J one of which is shown in full lines in Figs. 2 and 3,'. and are indicated by broken lines in Figs. l, 2 and 3. Referring to Fig. l, it will be seen that the segmental recesses J, are staggered. From the chamber immediately behind each of the valves E, an exhaust port K, leads into the segmental recess J, and from each of said chambers an exhaust duet L, leads into the chamber of lthe opposite small piston F.

It will be noticed that both of the sleeves D, can be removed from the piston C, by removing the cylinder-head A', without removing the piston C, from the cylinder A, so that I am thereby able to remove and` replace the said sleeves D, and the valvemechanism mounted therein, when desired. In operation, when steam is introduced into the end A2, of the cylinder A, the pressure thereof enters into the passage H, and forces lthe piston F, backward, which action of the piston F, closes the valve E, and compresses the spring G, and at the same time said 'piston covers the end of the exhaust opening L, thereby forming an air cushion Patented oct. 6,1914, Application filed March 29, 1913. Serial No. 757,528.

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between the pistonF, and the plug D'. Meanwhile the piston C, travels vbackward toward the end A2, of the cylinder A, and at a point near where the central exhaust ports B, are uncovered by the piston C, the

, pressure in the end A2, of the cylinder 3A,

will be relieved, which also relieves the pressure on the piston F, through the passage H, and permits the spring G, to open the valve B, so that on the return of the piston C, toward the end A2, of the cylinder A, steam may pass freely through the casing .D, passage K, and segmental chamber J,

until the end y', of, said chamber, has passed the point, b, of the central .exhaust port B, when compression in the 'end A2, of the cylinder A, will begin to accumulate until the intensity thereof is suiiicient to act upon the piston F, through the passage H, to compress the springA G, and close the valve E, when said valve will be retained in a closed position until the central exhaust ports B are again uncovered, or nearly so. The action of both the valves shown in the piston, 'is identical, one valve operating from the end A2, of the cylinder, and the other valve operating from the end A3, of the cylinder.

ln the construction shown in Fig. A, the spring Gr, for opening the valve E, is dispensed with, and the exhaust passage L, from the chamber of the piston F, is not used, and in lieu thereof the piston F, is provided with a steam passage, M, leading from the chamber of the piston F, to the end A2, of the cylinder A.

lllie operation of the construction shown in Fig. A, is as follows, viz z-When the piston C, travels backward toward the end A2, of the cylinder A, the pressure in the end A2, gradually decreases until the central ports B, are uncovered, during which time the pressure in the end A3, communicated through the passage `M, to the chamber of the piston F, has increased until the intensity thereof is sutlicient to cause the piston F, to open the valve B, and hold it open until the piston C, has traveled backward toward the end A2, of the cylinder A, to reduce the pressure inthe end A2, of the c linderA, and to increase the pressure in the end A2, of the cylinder A, communicated through the steam passage l-l, in the piston C, to the chamber of the piston F, sucient to cause said piston F, to close the valve F, and maintain it in a closed positiony until the piston C, has again uncovered they cen.- tral exhaust ports B, or nearly uncovered them. ln all other respects the operation of the construction shown in Fig. A, is the same as that shown in Figs. l, 2 and 3.

From the foregoing description and the drawings, it will be obvious to those skilled in the art, that by the use of my invention,

l can construct a unidow non-condenstirarse ing engine, that is, an engine in which the steam flows continuously from the ends of the cylinder toward the central Vexhaust ports, without the employment of mechanically actuated' gear for operating exhaust valves. i

Therefore having fully shown and described my invention, so as to' enable others to construct and operate the same, What l claim as new, and desire to secure by Letters-Patent of the United States, is zl. rllhe combination with a steam engine cylinder having central exhaust ports, of a piston in said cylinder having exhaust passages therein adapted to communicate with said central exhaust po-rts, a valve in said piston controlling the exhaust to said ports, and'nieans within said piston actuated by pressure Within the cylinder for controlling said valve during the-compression and admission periods, substantially as `set forth.

2. The combination with a steam engine cylinder having central exhaust ports, ofy a piston in sail cylinder having passages adapted to communicate with said central exhaust ports, a valve in said piston adapted to control the exhaust through said passages to said ports, means within said piston to open said valve during the exhaust period of each stroke, and means Within the piston actuated by pressure Within the cylinder for closing said valve during the compression and admission period, substantially as set forth.

3. lin a steam engine, a cylinder having central exhaust ports, an engine-piston in said cylindery having steam passage-ways and valve and piston chambers therein adapted to communicate with said central exhaust during the -reciprocation of said engine-piston and with the interior of said cylinder, a valve adapted to close said valvei chamber, a' valve-stem thereon, a piston in said piston-chamber secured on said valvestein, adapted to be actuated by duid in that end of said cylinder toward which said engine-piston is moving to cause said valve to close the passage through said valvechamber and retain it in a closed position until the central exhaust ports in said cylinder are uncovered by the engine-piston on its return stroke and means contained within l said engine piston to operate said valve in the opposite direction, substantially asset forth. y

A. lin a steam-engine, a cylinder having central exhaust ports, an engine-piston vtherein adapted to cover and uncover said ports during its reciprocation having a valve-chamber and .steam passage-ways therein adapted to communicate with -said central. exhaust during the reciprocation of said engine-piston, and a piston-chamber and other steam passage-ways therein in 1,1 lane@ consta-nt communication with the interior of said cylinder and said piston-chamber and said. central exhaust, a valve adapted to close communication between the interior of said cylinder and said valve-chamber, a valve-stem thereon, a piston in said pistonchamber secured on said valve-stem and adapted to be actuated by fluid in that end of the cylinder toward Which the piston is moving, communicated thereto through some of the steam passages to operate said valve to close communication between said end of the cylinder and the valve-chamber in said engine-piston, and mechanism contained Within said engine piston adapted to operate said valve in the opposite directionv when said central exhaust ports are uncovered on the return stroke of said piston, substantially as set forth.

5. In a steam engine, central exhaust ports, an engine-piston therein adapted to cover and uncover said central exhaust ports duringits reciprocations, having therein a valve-chamber in said. engine-piston, a depressed recess in the periphery of said piston, an exhaust port extending between said valve-chamber and said depressed recess, a piston chamber, a steam passage-Way leading from one end of said engine-piston to one end of said piston-chamber, and another passage-Way leada cylinder having ing from the opposite end of said pistonchamber to said central exhaust; a valve mounted in said engine-piston, a valve-stem thereon, a piston in said piston-chamber and secured on said valve-stem adapted to be actuated by fluid in said cylinder to cause said valve to close communication between the interior of said cylinder and the valvechamber in said engine-piston and retain saidl valve in a closed position until said central exhaust ports are uncovered by the return stroke of said engine-piston, and means to move said valve in the opposite direction, substantially as set forth.

6 In a. steam-engine, a cylinderv having central exhaust ports, a piston therein adapted to cover and uncover said central exhaust .ports during the vreciprocations thereof,y having al longitudinal chamber therein, a steam passage-'Way leading from the end of said piston into said chamber and a passage-Way communicating between said chamber and said central exhaust, a sleeve secured in said chamber having the inner endthereof closed and a valve-seat opening in the outer end and a valve-stem opening in the closed inner end thereof, a valve seated upon said valve-seat opening, a valvestem thereon and extendin into said piston chamber, a piston in saig piston-chamber vsecured onsaid valve-stem, said engine-piston having a depressed recess in its periphery and an auxiliary exhaust port extendingtherefrom into said sleeve, and spring mechanism adapted to open said valve When there is no pressure i that end of the cylinder, substantially as set forth.

In testimony whereof I aflix myy signature, in presence of tivo Witnesses.

ROBERT C. STEVENS.

Witnesses:

` JOHN B. BRooxs, f I-I. M. STURGEON.