US1016210A - Means for converting vapor energy into work. - Google Patents

Description

E. I. CHRISTIE.

, MEANS FOR CONVERTING VAPOR ENERGY INTO WORK.

APPLICATION FILED JULY 14, 1909 RENEWED MAY 29, 1911.

1,016,210, Patented Ja11.30, 1912;

$2 9M I $4M; (ma m gag COLUMBIA PIANOORAPH 60., WASHINGTON, n. c-

ELZA J. CHRISTIE, 0F MARION, IOWA.

MEANS FOR CONVERTING VAPOR ENERGY INTO WORK.

Specification of Letters Patent.

Patented Jan. 30, 1912.

Application filed July 14, 1909, Serial No. 507,598. Renewed May 29, 1911. Serial No. 630,122.

To all whom it may concern Be it known that I, VELZA J. CHRISTIE, a citizen of the United States, residing at Marion, in the county of Linn and State of Iowa, have invented certain new and useful Improvements in Means for Converting Vapor Energy into Work, of which the following is a specification.

This invention relates to the generation of power for mechanical or other purposes, and more particularly to a type of engine wherein steam mixed with compressed air is the principal Working medium.

The object of the invention is to secure a more economical use of steam in a number of particulars, namely: First, to secure a better distribution of steam pressures and the consequent higher mean effective pressures in the working cylinder. Second, to secure a considerable amount of super-heating of the steam as it enters into the cylinder and difiuses itself into the compressed air therein contained. Third, to secure a heterogeneous working medium during expansion, said medium composed of air and steam intimately mixed, the air having a coeiiicient of expansion different from the coefficient of expansion of the steam, so that when this heterogeneous working medium is expanded adiabatically against resistance, performing work, after reaching the point of saturation, its further expansion causes a transfer of heat from the steam to the air. Fourth, to provide a heterogeneous working medium in the working cylinder, said medium composed of compressed air and steam. The proportion of air to steam may be such that at the end of the expansion stroke, the pressure of the air inside of the cylinder is approximately equal to, or greater than, the back-pressure of the external atmosphere, while the steam pressure in the cylinder is still a useful working pres sure and does not waste its heat or work by the resistance or back-pressure of the external atmosphere, thus dispensing with the necessity of the well known costly condenser and its expensive operation. Fifth, and comprehensive of the preceding, to utilize atmospheric air or atmospheric air and vapor to mix with the steam and to secure thereby the advantages mentioned above, and said advantages will more fully hereinafter appear. Sixth: to greatly decrease and almost entirely avoid cylinder condensation.

The nature of the invention is fully disclosed in the description and claims following, reference being had to the accompanying drawing, in which the figure gives a plan view partly in section of an engine adapted to utilize the heterogeneous mixture of gas and vapor or air and steam above referred to, and thus carry into' effect the invention as indicated above, and referring now to the drawing, 1 denotes the cylinder of a reciprocating engine provided with the usual piston and piston-rod 2 communicating with the crank 3 by connecting-rod 4 in the usual way. To the crank-shaft is attached the usual fly-wheel 5 and a bevel-gear 6 which transmits motion to the valve gear in a manner to be described presently. The engine is supplied with steam from a boiler 7 through a pipe 8 provided with a throttle 9, and pipe 8 may be provided with any form of throttlegovernor which need not be here shown, as it does not constitute any part of this invention. The exhaust passes out through pipe 10.

The valve gear herein shown is a simple four-cycle type and will now be described.

The cylinder is supplied with two heads 11, the only essential difference between them being that one is the front head provided with a stufling-box 12 for the pistonrod, which stufiing-box is dispensed with in the case of the back head as shown. These heads are provided with suitable chambers 13 fitted with an intercepting pop-valve 14L actuated by a spring and the cam 15 on the cam-shaft 16. The chamber is also provided with a checking valve 17 to check against the pressure of the air'inside of the cylinder while undergoing compression. The heads are also provided with inlet air ports 18, normally closed by spring actuated pop-valves 19 and moved to open by cams 20 on the same cam shafts. Ports 21 serve as exhaust ports and are fitted with similar pop-valves 22 closed by springs and actuated by cams 23 on the same cam shafts. The

cam shafts 16 are driven by gearings 24:

through the medium of a longitudinal shaft 25 provided with a bevel-gear 26 of double the diameter of the bevel-gear 6 already mentioned, so that the valves are operated only at every second revolution of the crankshaft.

The other parts of the engine are all of a familiar construction and need no parexhaust valve 22.

ticular description. It is tobe noted,however, that no attempt has been made torepresent the bed-frame of an engine, since this forms no essential feature of the invention.

The operation of the engine is as follows :Supposing the boiler to be supplied with steam under working pressure. While holding valves 19 open by hand, the crankshaft is then turned by hand until the cam-- 15 is just ready to open valve 14 in therighthand head. Air inlet valves 19 are then released and closed, and the engine is now ready to start by a further turning of the crank-shaft in the same forward direction. The following description of the operation of the valves has reference to the valves in the right-hand cylinder .head, while the valves in'the left-hand cylinder head operate in the same manner, but just one stroke later. By the further turning of the crankshaft asabove described, cam 15 opens valve 14 and the steam pressure opens valve 17 thus admitting steam into the cylinder at the right-hand end, thus starting the engine by the steam pressure direct upon the piston. Cam 15 may beso constructed that it releases valve 14 at any desired point along the working stroke in order to out off the further introduction of steam and to finish the working stroke by the expansion of the working medium in the cylinder. For the purpose of illustration, let'us say that cam 15 releases and valve 14 closes at the expiration of the first third of the working stroke, the piston moving to the left to the end'of the stroke. Valve 17 closes almost simultaneously with valve 14. Now, as the piston begins the return stroke to the right, cam 23 opens exhaust valve 22 and holds it open to the end of the stroke, thus permitting the spent steam to exhaust through port 21' and pipe 10 into the atmosphere, then cam 23 releases and the spring closes The engine is now in motion with. good speed and the continuous operation of the same may be described as follows First cycle: By the momentum of the flywheel, the piston moves to the left, while cam 20 opens and holds open valve 19 and the cylinder fills with atmospheric air, then at the close of the stroke, cam 20 releases and the spring closes valve 19.

.Second cycle: By the momentum of the fly-wheel, the piston now moves to the right and the air and remaining vapor in the cylinder are compressed to the end of said stroke. If the pressure of this compressed air is greater than the pressure of the steam in the boiler, it forces open Valve 14 and part of the compressed air passes into chamber 13 and increases the pressure which tends to hold valve 17 closed.

Third cycle: By the momentum of the flywheel, the piston enters upon the third strOke, which is 'to the left, and the pressure of the compressed air is exerted upon the piston throughout the entire stroke. Also, at the instant of beginning this stroke, cam 15 either opens or engages to hold open valve 14, and when the pressure per square inch in chamber 13 is less than the pressure per square inch in boiler 7 valve 17 opens and steam from the boiler flows into the cylinder and exerts its pressure on the. piston. hen the piston reaches the end of the first third of this stroke, (or any other desired fractional part of the stroke) cam 15 releases and the spring closes valve 14 and almost simultaneously the spring closes valve 17. The remainder of this stroke is completed by the expansion of the heterogeneous mixture of air and steam, and the entire stroke may be called the workingstroke.

Fourth cycle: The fourth stroke is to the right, and at, or shortly before, the instant of beginning said stroke, cam 23 opens valve 22 and holds it open to the end of the stroke, thus exhausting the contents of the cylinder through port 21 and pipe 10 into the atmosphere. At the close of this stroke, cam 23 releases and the spring closes valve 22. The cycle of the left-hand head and its valves are the same but just one stroke later or, we may say the succeeding stroke.

With the continuous operation of the engine, this general four-cycle operation above described is repeated continuously.

Chamber 13 may be of great practical importance and may constitute any fractional portion of the total clearance or compression space of the engine.

From the above described methods of operation, it must follow that, first, under Daltons laws, the saturated steam from the boiler mixing with the compressed air in the cylinder becomes highly super-heated. Second. The high temperatures of compression totally evaporate all particles of moisture on the cylinder walls. Third. The two foregoing facts avoid cylinder condensation. Fourth. The super-heated mixture, in the early part of the working stroke, soon becomes saturated, and the latter and greater portion of the expansion is performed by the saturated mixture, in which a very large portion of the latent heat of the steam is transferred to the air in the expanding mixture, and this is the same latent heat which is lost in the exhaust of the present steam engine. Thus the compressed air is re-heated throughout the entire expansion and more work performed.

Having thus described my invention and its methods of operation, what I claim as new and desire to secure by Letters Patent 1s 1. A motor adapted for the use of a mixture of steam and compressed air or neutral gas, comprising a suitable cylinder with a piston mounted to reciprocate therein, one or more heads attached thereto and valves respectively adapted to admit steam and air and to allow for the exhaust of the spent mixture, a valve gear adapted to successively open the air valve on one stroke and the steam valve on the following second stroke thereafter and the exhaust valve for the final emission of the spent mixture on the next stroke, and mechanism adapted to actuate the valves in sequence whereby atmospheric air is compressed in the cylinder and steam is admitted to and commingled with the compressed air to perform the work.

2. In a motor adapted for the use of a mixture of steam and compressed air, the combination of a working cylinder having a reciprocating piston therein, and valves respectively adapted to admit atmospheric air at one stroke and to hold it in the cylinder while undergoing compression on the return stroke, another valve adapted to admit steam at the next succeeding stroke to commingle with the compressed air and final exhaust valve, and means for actuating these respective valves in due time and sequence.

3. In a motor adapted to use steam and compressed air, the combination of a cylinder, a piston working therein, a valve adapted to admit atmospheric air to the cylinder and to hold it until compressed therein, a check valve adapted to admit steam into the compressed air chamber and hold back said compressed air when its pressure exceeds the steam pressure, an exhaust valve 'to permit the emission of the spent mixture and valve gearing adapted to actuate said valves in proper time and sequence.

4. In a motor adapted to use steam and compressed air, the combination of a cylinder, a piston working therein, an inlet chamber for steam external to the cylinder and adapted to serve as a compression chamher, and valves adapted to respe'ct-ively admit atmospheric air to the cylinder and to the compression chamber, check against back-pressure to the boiler, to admit steam to the compression chamber and to the cylinder, and to regulate the exhaust of the spent mixture therefrom.

In testimony whereof I affix my signature in presence of two witnesses.

ELZA J. CHRISTIE.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G.

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