US707452A - Valve-motion. - Google Patents

Description

No. 707,452. Patented Aug. l9, I902. G. M. SCHWEND.

VALVE MOTION.

(Application filed Oct. 8, 1901.)

(No Model.)

2 Sheets-Sheet I.

W/TNE 8E8: Q nwslvrofi 196 JM. Scixwaad.

ATTORNEYS VALVE MOTION. (Application filed Oct. 8, 1901.)

2 Sheets-Sheet 2.

(No Model.)

Fay. 5.

INVENTOR 2607 e Sciwencl wmvsssss W @d w A TTOHNE 78 m: yacmms PETERS co PHOYO-LlTHQ" wnsmworou. n. c

" rrn GEORGE MARTEEN SCHWEND,'OF BIRMINGHAM, ALABAMA.

VALVE-M OTION.

SPECIFICATION forming part of Letters Patent NO. 707,452, dated August 19, 1902.

Application filed October 8, 1901. Serial No. 77,975. (No model.)

To all whom it may concern:

Be it known that I, GEORGE lVIARTEEN SCHWEND, of Birmingham, in the county of Jefferson and Stateof Alabama, have invented a new and useful Improvement in Valve- Motions, of which the following is a specification.

My invention relates to an improvement in valve-motions for reciprocating steam-engines, and has for its objects to simplify the construction of such motions, render the action of the valves more effective to utilize the steam in a more direct manner, and to provide a simple and effective condensationdrain device and a resulting saving of fuel.

To these ends my invention consists in providing the cylinder-heads of a steam-engine with coacting exhaust-valves which are alternately opened and closed by the piston through the medium of connecting-rods, exhaust-passages controlled by such exhaust-valves, and a jacket or casing in communication with the exhaust-passages and wholly or partly surrounding steam-cylinder and'having an exhaust-opening to the outer air or a condenser.

My invention also consists of certain details of construction and the arrangement and combination of parts, as will be hereinafter fully described and claimed.

In the drawings, Figure 1 is a central vertical longitudinal section; Fig. 2, a vertical transverse section on line 2 2 of Fig. 1; Fig. 3, a horizontal longitudinal section on line 3 3 of Fig. 2 looking in the direction of the arrow; Fig. 4, an inside View of one of the cylinderheads; Fig. 5, an outside view of the same head; Fig. 6, a detail View of one of the exhaust-valves and a portion of its accompanying working mechanism.

1 represents a steam-cylinder provided with a steam-chest 2 and balanced slide-valve, as usual, and the heads 3 3. Each head is made somewhat thicker than usual and is provided at its rear with annular flanges projecting from said thickened portions, the purpose of which will be presently described. The inner faces of the cylinder-heads are provided with cavities or recesses at of peculiar shape, having therein the seat for the exhaust-valves 5 5. This recess is provided with an opening 17 at the rear, through which the stem of the downwardly into and forwardly through the cylinder-head is a passage 8, which leads through a cut-out portion 15 of the cylinder registering therewith and further communicates with a jacket or casing 9, which extends upwardly and surrounds the cylinder to about one-half or two-thirds its height, or it may entirely surround the same. This jacket is provided with an opening 10 in its side, which communicates with the atmosphere or condenser, as the case may be. The cross-heads attached to the exhaust-valves are adapted to be received and seated, as stated, in the transverse horizontal cavity or groove 7, and over said recess or groove may be secured by a steam-tight joint the curved cover-plate 11, or the cylinder may be made sufficiently thick to allow for the movement of the cross-head, in which instance a flat cover-plate may be used. Each cylinder-head has seated within it a cross-head, and said cross-heads are connectedby the rods 12, secured to the cross heads at or near the outer ends of the same.

The valve 5 consists of the head 5, beveled on its rear face, and the stem 5 which is secured, as stated, to the cross-head 6. This valve when seated closes the passage 8, leading through the cylinder-head to the jacket or casing 9, and it may be made any suitable shape and may have one or more stems connecting it with the cross-head, but is preferably made circular in shape, as shown. The valve-recess containing the valve-seat is made in the peculiar shape shownthat is, scalloped or with pockets 13--the purpose of which will be hereinafter set forth.

The steam-chest is made as long as the cylinder, with steam-ports at or near the ends of the cylinder, which ports lead to the ends of the cylinder, so thatthe steam is admitted directly at the cylinder-heads in front of the piston. The valves in the steam-chest are of the balanced type and just high enough to receive the yoke around them. They have the balance-strips on top. The balanceplato is low enough to let steam circulate over the top of plate, so that there will be a free admission of steam to both sides of both valves.

The exhaust-valves 5 are located, as shown, in the lower portion of the cylinder-heads and consist, as stated, of the valve head proper, 5, having the valve-stem 5, connecting the head with the cross-head, and the cross-head of one valve is connected with that of the other valve by the connecting-rods 12 in such a manner that when the valve in one cylinder-head is open the valve in the opposite cylinder-head is closed. The cylinderheads are made of such thickness that when the exhaust-valve is closed the front face of the same will be flush with the inside face of the cylinder heads. The scalloped shaped pockets 13 around the exhaust cavity or recess are adjacent to valve-seat in order that the steam may surround the said valve-seat and on the opening of the valve pass instantly into the passage connecting the exhaust-recess with the opening in the inner face of the cylinder-head, which establishes communication withthe space inclosed by the casing or jacket surrounding the cylinder, and thence to the atmosphere or condenser. Each exhaust-valve has secured to the center of its front face a cushion consisting, preferably, of a coiled spring 14 of the proper length and tension, which projects forwardly into the cylinder, the purpose of said spring being to receive the initial impact of the piston-head in its travel toward the cylinder-head. As the piston comes in contact with the spring it will compress the same and cause the exhaust-valve to travel gently into the cylinder-head and seat itself, thus avoiding jarring and shock and sudden closing of the valve. At the same time that one valve is thus seated the opposite valve is moved off its seat, letting escape the exhaust-steam, which passes through the passage in the cylinder-head into the space surrounded by the casing or jacket which surrounds the cylinder, where it serves the purpose of heating the cylinder before it finally passes out of opening 10, resulting in an economy of steam and consequent saving of fuel. The annular flanges of the cylinder-heads are provided with holes 16, through which pass the connecting-rods 12, said rods being inclosed by the jacket or casing 9, which is secured to the said flanges by bolts or other suitable means and has a steam-tight connection with the same. The exhaust cavity or recess being situated at or near the bottom of the cylinder will cause any water of condensation that may have collected to flow into the exhaust cavity or recess upon the opening of the exhaust-Valve and thence into the space inclosed by the jacket or casing surrounding the cylinder, whence it may be drawn 01f bysuitable means. This draining ofi the water of condensation will prevent the same collecting in the steam-cylinder to such an extent as to give rise to the danger of forcing off the cylinder-head, as is sometimes the case where no provision is made for such drainage.

This device may be used on any kind of a steam-engine, either stationary or locomotive. If used on a locomotive-engine, no change will be required in the valve-gear, such as links, eccentrics, rocker-arms, 650. One or two balanced slide-Valves may be used in the steam-chest. If one is used, it will be placed in the center of the steam-chest, with a bridge of the proper width to divide the steam-ports. If two valves or a double valve is used, they will be placed near both ends of the steamcylinder, as shown in the drawings. The valves will have to be just high enough to receive the yoke around them. They can be perfectly balanced, as there is no exhaust to knock them off their seat, the exhaust taking place through the novel exhaust valves and passages described hereinbefore.

It will be clearly seen that my device does away with the usual exhaust-ports, and the necessity of carrying the exhaust steam through. the slide-valve and steam-chest is avoided.

The operation of the engine is as follows: Steam is admitted to the steam-chest by a pipe in top of same and through the medium of the balanced valve passes through the port in one end of the cylinder (the exhaust-valve in which the end is closed at that time) in front of the piston-head and forces the piston toward the opposite end of the cylinder. WVhen the piston nearly reaches the opposite end, it comes in contact with the projecting coil-spring secured to the exhaust-valve in that end of cylinder and gently and grad ually closes the said exhaust-valve. At the same instant the exhaust-valve in that end of'the cylinder which has just received its live steam is opened by means of the rods connecting the two exhaust-valves and allows the steam back of the piston to exhaust through the exhaust-cavity and connecting-passage with the space surrounded by the jacket or casing 9, where it serves to warm the cylinder before passing to the atmosphere or condenser. The above operation is repeated alternately at each end of the cylinder.

For a cross compound engine this valve-motion will be found superior to that commonly used, as one end of the cylinder is open to receive steam until the stroke of the piston is completed regardless of how much expansion is used. By reason of the fact that in my de vice none of the exhaust-steam goes through the steam-chest and slide-valve I admit steam to cylinder from both sides of the valve at the same time.

Having thus described myinvention, what I claim as new, and desire to secure by Letters Patent, is-

1. The combination with the cylinder, cylinder-heads, inclosed piston-head, exhaustrecesses in the inner faces of said cylinderheads, having valveseats, exhaustvalves working in said recesses, coiled springs attached to the front ends of said valves, stems secured to the valves, cross-heads attached to the valve-stems, connecting-rods secured to the cross-heads, cavities or grooves in the outer faces of the cylinder-heads adapted to receive the cross heads, passages leading from the exhaust-recesses in the cylinderheads through the same, a jacket or casing partly or wholly inclosing the steam-cylinder, said casing inclosing an eXhaust-steam cylinder heating-space, having communication with exhaust-passages in the cylinderheads, an opening in said jacket or casing communicating with the atmosphere or condenser, and means for alternately admitting live steam to each end of the cylinder, substantially as shown and described.

2. The combination with a steam-cylinder having cylinder-heads and inclosed piston, of exhaust recesses or cavities in the cylinderheads, valve-seats in the said exhaust-recesses, scallops or pockets adjacent to'and surrounding said valve-seats, exhaust-valves comprising a head, coiled springs secured to the head of said exhaust-valves and projecting forwardly therefrom, a stem projecting rearwardly from the valve-heads, cross-heads secured to the valve-stems, a cavity or groove in the rear face of each cylinder-head, adapted to receive the cross-heads, passages leading from the exhaust-recesses, downwardly and forwardly through the cylinder-heads, exhaust-steam spaces surrounding the cylinder and communicating with the exhaustpassages, rods connecting the cross-heads of the exhaust-valves, said rods passing through the cylinder-heads and within the exhaust steam space surrounding the cylinder, and means substantially as described for admitting steam alternately to the ends of the cylinder.

3. In a steam-engine, the combination with a cylinder and cylinder-heads, exhaust-recesses in said heads, passages leading from the recesses through the cylinder heads, valve-seats in said recesses, scallops or pockets adjacent to and surrounding said valveseats, and an inclosed piston, of exhaustvalves adapted to be seated in said valveseats, and each having rearwardly-extending stem, cross-heads attached to-the stems, and rods connecting the said cross-heads, whereby the valves are adapted to be alternately opened and closed by the impact of the piston against the faces of said valves.

4. A steam-engine comprising a cylinder, cylinder-heads, a jacket separated from and surrounding said cylinder, exhaust-recesses in the cylinder-heads communicating with the space formed between the jacket and the cylinder, a piston, and steam-chest provided with a steam-inlet, exhaust-valves in said exhaust-recesses, rods connecting said exhaustvalves, whereby the said valves are adapted to alternately open and close, and means in the steam-chest for admitting steam directly therefrom, alternately to the ends of the cylinder.

5. In a steam-engine, cylinder-head exhaust-valves located in each cylinder-head and adapted to alternately project into the cylinder, said valves each consisting of a head, a stem and a spring projecting forwardly from the face of the valve into the cylinder, said projecting springs being adapted to receive the impact of the piston-head and be compressed thereby, whereby the exhaust-valves will be gently moved to their seats, and rods connecting said exhaust-valves.

6. In a steam-engine, the combination with a cylinder, cylinder-heads, inclosed piston, exha ust-passages in the cylinder-heads,valveseats in the said exhaust-passages, scallops or pockets adjacent to and surrounding said valve-seats, of exhaust-valves comprising a head, a stem, forwardly-projecting compressible cushions secured to the front face of the valve, and rods connecting the said valves, whereby they are adapted to alternately open and close the exhaust-passages in the cylinder-heads by the impact of a piston.

'7. A cylinder having its heads provided with sockets in their inner facesadapted to receive exhaust-valves,scallops or pockets adjacent to and surrounding said sockets, said valves carrying forwardly-proj ectin g springs adapted to receive and be compressed by the impact of a piston, whereby the faces of said valves will be caused to lie flush with the inner faces of the heads, when moved to their seats.

8. A steam-engine comprising a cylinder, cylinder-heads, exhaust-ports in said cylinder-heads, a piston, a steam-chest provided with a steam-inlet, exhaust-valves in the said exhaust-ports, rods connecting said exhaustvalves whereby they are adapted to alternately open and close, and means wholly within the steam-chest for admitting steam directly therefrom, alternately to the ends of the cylinder between the cylinder-heads and piston.

GEORGE MARTEEN SCHWEND.

Witnesses:

W. H. OwINe's, J NO. H. HILL.

Images