US1539200A - Cut-off valve for steam engines - Google Patents

Description

B. F. QBRYANT CUT-OFF VALVE FOR STEAM ENGINES Original Filed May 1921 May 26,1925.

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l TTUHNEYS WITNESSES W Patented May 26, 1925.

UNITED STATES PATENT OFFICE.

BENJAMIN F. OBRYANT, OF GADSDEN, ALABAMA, ASSIGNOR OI ONE-HALF TO I. M.

ROSEN, F GADSDEN, ALABAMA. I

CUT-DEF VALVE FOR STEAM ENGINES.

Application filed May 12, 1921, Serial No. 468,905. Renewed March 30, 1925.

T 0 (1H whom it may concern:

Be it known that I, BENJAMIN F. OBRYANT, a citizen of the United States, and a resident of Gadsden, in the county of Etowah and State of Alabama, have in vented certain new and useful Improvements in Cut-Off Valves for Steam Engines, of which the following is a specification.

This invention relates to cut-off valves for steam engines.

' ward head of one of the cylinders to b blown out or in some manner knocked off; When this condition arises it has been the practice to lock or block the valve controlling the entry of steam to the cylinder in such a position that any possibility of steam escaping into the cylinder is eliminated. The operating means for the valve is also'at the same time disconnected and thus rendering the entire cylinder inoperative. In some cases the engine may proceed by operating with one cylinder. It often happens however, that when the forward head is blown from one of the cylinders, that the piston of the other cylinder is at a point of dead center. In an instance of this kind, the engine becomes entirely out of commission in that the piston within the cylinder which has not been broken cannot be started.

With the above in view, it is the object of the present invention to provide a valve by which the admission of steam into the forward end of a cylinder of the above mentioned character may be stopped with out impairing the normal operation of the controlling valve and thereby permit a piston within a cylinder having its forward head broken away to continue to make a forward power stroke. This is of great value in case the other piston is on dead center in that the forward stroke would be sufiicient to start the engine and move the other piston off of dead center thus enabling the same to start. The engine may then continue to proceed upon its way, the piston in the broken cylinder operating in the usual manner but only transmitting power during its forward stroke.

The invention is illustrated by way of example in the accompanying drawings, in Which- Figure 1 is a vertical central sectional view of thecylinder, steam chest and valve operating mechanism as commonly employed on the one side of a railroad locomotive,

Figure 2 is a vertical section taken substantially on the lines 2-2 of Figure 1, and

Figure 3 isia detail perspective view of the cut-off valve.

Referring to the drawings more particularly, indicates generally a cylinder of the type heretofore referred to, 11 the for-. ward head thereof, and 12 the rearward head. On top of the cylinder there is formed the usual steam chest 13 which is formed with the extended hollow portions 14- and 15, said portions beingin alinement with each other and each adapted to slidingly accommodate one of the heads of the double headed valve member 16. The steam chest and cylinder together with their associated parts are carried by the body of the engine through the means of the extension 17, Figure 2, and the plates 18 as shown in Figure 1. i

The cylinder '10 is provided with the usual piston 19. and said piston being connected through the connecting rod 20 for actuating the drive wheels on one side of the engine; The wall 21 which extends between the steam chest 13 and cylinder 10, is provided with the usual ducts 22, one at each end thereof as shown; also the extensions 14 and 15 are each provided with an exhaust port as indicated at 24, and communicating with the interior of the steam chest 13 is a steam supply pipe 26. The operation of the valve 16 for permitting steam to enter the ducts 22 and also exhausting therefrom, so that the piston 19 will be reciprocated within the cylinder 10 is well known and understood so that no detailed explanation thereof need here be made.

In carrying out the present invention, I provide a bore 27 which is transverse to the duct 22 and preferably passing therethrough at the point shown. The bore 27 is adapted to accommodate the circular heads 28 of the valve member 29. The portion 30 which connects the two circular head members 28 of the valve member 29 has an inner surface which corresponds in curvathe object being that when the portion of the valve rneniber is disposed as shown in light cross section lines in Figure 1, the same will not offer any interference to the flow of steam through the duct, but when disposed as shown in heavy cross section lines in the same fi'gi'ir'e', said portion will form a tight closure against any flow of steam through said duct. The outer end of the valve 29 is covered by a cap 31, which is secured against removal by the means of screws as indicated at 32. The outer circular head of the valve member is also forined with a square recess as indicated at 33; and 1n alineinent with sa d recess there is threaded into the head of the cap" 31 a plug 34, said plug having a squared portion 35 to which a wrench may be applied for removing the same, a set screw 31" serving to adjustably hold the valve mernber 29.

In the use of the present invention, as-

- smiling that the engine with which the same is to be associated is the two-cylinder type, that is, a cylinder located on each side i of the engine, each cylinder would then be provided with a cut-off valve, the same being located in the forward duct 22 in each instance Now in case the forward head 11 would be blown from either of the cylinders thenit would only be necessary to remove the plug 345 and by the use of a square bar and wrench turn the valve member 29 so that the same will be disposed as shown in Figure 1', and at which time the duct 22 would be open. No steam can then escape from the steam chest 13 into the forward end of the cylinder 10. The closing of the forward duct 22- would however in no way interfere with the operation of the valve 16, and therefore the valve Ihay operate so that a forward power stroke of the piston 19 may be; utilized. As before mentioned the fact that this forward stroke of the piston 19 can be utilized as driving power is of greatiadvantage in case the piston of the other cylinder should happen to be at dead center at the tiine when the cylinder head 11 was blown off.

Also, it isto be noted that by the use of the present invention, in case a cylinder head is broken, that it takes but a few minutes to cut olfthe steam from the forward end of thecylinder impaired and perinit the engine to proceed. This a great saving of time when viewed with the old practice of blocking and disconnecting the controlling valve heretofore referred to.

A Valve member removably mounted in a bore extending transversely of a passage, said passage and bore being formed in a body member and said bore having its inner end closed, and said valve member comprising a pair of "circular heads and a connecting portion therebetween adapted to be utilized for controlling fluid flow through the passage, saidv valve nieinbe-r having one circular head slightly extending from the open end of bore, a cap fitted upon the last named end of the valve, a securing flange formed with the cap whereby the same may be secured to the body member, and a set screw threaded through a side wall of the cap whereby the valve member may be adjustably held against rotation.

BENJAMIN F. OBRYANT.

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