US251809A - Steam-engine cylinder - Google Patents

Description

militia Nrrnn STATES PATENT FFICQ WALTER J. ALLEN, OF ERIE, PENNSYLVANIA,

STEAM-ENGINE CYLINDER.

SPECIFICATION forming part of Letters Patent No. 251,809, dated January 3, 1882.

Application filed May 12, 1881. (No model.)

Toall whom it may concern Be it known that I, WALTER JAY ALLEN, a citizen of the United States, a resident of Erie, Erie county, Pennsylvania, have invented new and useful Improvements in Steam-Engine Cylinders; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawing and the letters or figures of reference marked thereon.

My invention consists in providing devices upon the cylinder of a steam-engine for admitting the steam which has just driven the piston in one direction to the opposite side of the piston, so as to cushion it and fill the entry-ports just previous to'the exhausting of said steam from the cylinder.

I am aware that means have heretofore been provided for transmitting steam in the manner described above from one sideof the piston to the other for the purposes mentioned, and therefore I do not claim, broadly, devices for so doing. I

My invention consists in providing certain improvements in the devices for so conveying steam from one side of the piston to the other just previous to the exhausting of the steam for thepurpose of cushioning the piston and filling the entry-ports before the admission of steam thereto, which improvements will befully set forth in the following description and claims.

My device is illustrated in the accompanying drawing asfollows: a single figure, which is a longitudinal vertical section, with the steamchest indicated by dotted lines, and having the parts indicated by letters of reference, as followse A is the cylinder; B, the piston, which is shown in the positionit occupies just previous to the exhaust of steam at the opposite end of the cylinder, and also previous to the admission of live steam at the end of the cylinder where the piston is.

a is the clearance-space.

D is a passage within the wall of the cylinder, spanning the piston when at or immediately before it reaches the exhaust-line.

O is a check-valve located in the passage D at its end nearest the middle of the cylinder, and opening from the body of the cylinderchamber toward the clearance-space.

forms of large ones.

0 is a plug or cage containing the check-valve,

and screws into the passage D from the out- .check-valve for keeping the same closed except when opened by the pressure of steam. This spring will only be necessary when the plugs are so placed that gravity will notact to close the valve, but may he used at any time, if desired.

The passage D maybe located at any point on the cylinder, as they do not come in contact with the ports. If the steam-chest is on the side of the cylinder, they may be on top, and if the steam-chest is on top they may be on the side of the cylinder. The passages I) are cored out in the casting of the cylinder. The plugs 0 care of any metal desired-say brassand are screwed into holes cored or drilled through the wall of the cylinder in contact with the passages D. This cage is provided with a port, 61, which registers with passage D, to allow the steam to escape from the cage into the passage. I am aware that a passage for this purpose has been formed by using pipes outside the cylinder, and in which was located a check-valve5 but such a construction is not practical on small engines, nor on many My device is adaptable to any form of reciprocating engine.

The object of the check-valveO is as follows: When the piston passes the mouth of the passage leading to the check-valve the steam raises the valve and passes back of the piston into the clearance-space and entry-port and fills them. Immediately on this occurring the exhaust opens at the opposite end of the cylinder, and hence the pressure upon the checkvalve 0 is removed, and it closes by the action of the steam which has already passed it, and keeps this steam in the spaces named to serve as a cushion and to save the steam necessary to fill these spaces. Immediately after the exhaust and the closing of the check-valve G the engine takes steam back of the piston and the check-valve prevents it from passing through the passage D.

In the device referred to as having passages in the wall of the cylinder it was necessary for the piston to start on its return-stroke by the momentum of the engine, so as to close the passage before the engine could take steam; or, in other words, the engine could not take steam until the center was passed far enough to bring the piston over the inner opening of the passage. By my device it can take steam at any point, as the check-valve will close the passage D whenever there is pressure from that direction. The check-valve being arranged within the plug and within the passage D, it is easy of adjustment and quick to act, and, further, may be used on any size of engine.

I am aware that passages with check-valves have been used for the purposes shown, but not with the check-valves placed in a detachable plug or cage. Iam also awarethatin pumps and in other machines valves are often put into detachable cages, and so I do not broadly claim such a manner of setting the valve; but the construction I show is peculiarly advantageous in the construction of steam cylinders, as above set forth.

What I claim as new is- In asteam-cylinder, a passage formed within the walls of said cylinder for admitting steam from the body of the cylinder to the clearancespaces immediately before the exhaust takes place, said passage having at one end a cage provided with a port registering with the passage, and a Valve inserted from the outside of the cylinder and retained in said cage by a plug closing the outer end of said cage, which valve opens by pressure from the body of the cylinder-cavit y and closes by pressure from the clearance-space, substantially in the manner described.

In testimony that I claim the foregoing I have hereunto set my hand this 9th day of May, 188].

WALTER JAY ALLEN.

Witnesses:

J NO. K. HALLooK, W. R. EDELEN.

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