US792372A - Valve-gear for engines. - Google Patents

Description

310.792.372. I PATENTED JUNE 13, 1905.

J. L. WHEELER.

VALVE GEAR FOR ENGINES.

APPLICATION FILED OCT. 19, 1904.

2 SHEETS-SHEET l.

H nihiml 612M885: INVENTOH u ofinzjff zeezer Cf By ATTORNUS No. 792,372. PATENTBD JUNE 13, 1905.

' J. L. WHEELER.

VALVE GEAR FOR ENGINES.

APPLICATION 3211.31) OOT. 19, 1904.

2 SHEETS-SHEET 2.

WITNESSFS:

INVENTO EM JO/znl. 6 8222 A TTOR/VEYS UNITED STATES Patented June 13, 1905.

PATENT CEEioE.

VALVE-GEAR FOR ENGINES.

SPECIFICATION forming part of Letters Patent No. 792,372, dated June 13, 1905.

Application filed October 19, 1904. Serial No. 229,107.

To all whom it may concern:

Be it known that I, JOHN LAWRENCE WHEELER, a citizen of the United States, and a resident of San Francisco, in the county of San Francisco and State of California, have invented a new and Improved Valve-Gear for Engines, of which the following is a full, clear, and exact description.

This invention relates to improvements in devices for automatically cutting ofi the steam supplied to engines, particularly engines employed for heavy work, such as in sawmills, the object being to provide a cut-off of simple and inexpensive construction that may be arranged to cut off at a full stroke or at any desired point of stroke, resulting in an economy of steam and increasing the capacity of sawmill-work.

I will describe a valve-gear for engines embodying my invention and then point out the novel features in the appended claims.

Reference is to be had to the accompanying drawings, forming a part of this specification, in which similar characters of reference indicate corresponding parts in all the figures.

Figure 1 is a side elevation of a steam-engine with a cut-off mechanism embodying my invention attached thereto. Fig. 2 is a section substantially on the line 2 2 of Fig. 1. Fig. 3 is a sectional elevation of. a controllingvalve mechanism employed. Fig. 4 is a top view thereof. Fig. 5 is a side View of the governor or cut-off, and Fig. 6 is a section on the line 6 6 of Fig. 5.

Referring to the drawings, 10 designates the bed of the engine, on one side of which is a bracket 11, having an opening through which the cut-off cylinder 12 extends. This cut 0H cylinder has swinging motion, and therefore it is provided with trunnions 13, having bearings on the bracket, and one of these trunnions is provided with a port 14, which communicates with a port 15, extended longitudinally through a wall of the cylinder 12, and communicates With the interior of said cylinder near the bottom or underneath the piston 16, working in the cylinder.

The lower end of the cylinder is provided with a petcock 17, through which water may be drawn off, and extended from a lug 18 on the cylinder is an eccentric-rod 19, engaging with an eccentric 20 on the engine-shaft 21. The rod 22 for the piston 16 passes upward through a stuffing-box 23 and connects with a cross-head 24, movable vertically on guiderods 25, extended upward from the upper end of the cylinder. These guides 25 are provided each with a series of openings, and a stop-bar 26 is designed to be engaged in opposite openings in the guides, so as to limit or regulate the upward movement of the crosshead 24. To prevent undue jar as the crosshead moves downward, I provide cushions, here shown as springs 27, coiled around the lower portions of the guides and with which the lower side of the cross-head is designed to engage.

Pivotally connected to the cross-head is a link 28, which at the opposite end is pivoted to the stem 29 of a slide-valve of the ordinary construction in the steam-chest 30. Arranged on the steam-chest 30 is a controllingvalve mechanism consisting of a casing 31. This casing is provided with a longitudinal bore in which a valve 32 slides. This valve near its lower end is provided with an annular port 33, designed to open the steam-outlet port 34, which communicates, through the port 35, with the interior of the steam-chest 30. This valve 32 is also designed to control an exhaust-port 36, extended transversely through the casing 31, and at its outlet end it is provided with an outwardly-opening valve 37, Which Will permit the escape of steam, but will not admit the outer air. From the port 34 a supply-pipe 38 leads to and communicates with the port 14, and consequently with the lower end of the cylinder 12, in order to force the piston 16 upward, and upon relieving the pressure or exhausting the steam the piston will be moved downward by means of a spring 39, surrounding the piston-stem 22, and engage at one end with the piston and at the other end with the stufling-box 23. This pipe 38 serves not only to admit steam, as above mentioned, but it also serves for the exhaust, and therefore it is connected, by means of a branch 40, with the exhaust-port'36.

From the stem 41 of the valve 32 an arm 42 extends to a connection with the governorrod L3, which is moved longitudinally by the ordinary governor-balls L4. This arm 42, as clearly indicated in Fig. t, consists of two members clamped in engagement with the rod 43 and the stem 4:1 by means of bolts 45. On the stem 41 above and below the arm are jam-nuts 46 M.

The valve 32 is made of such length that neither port 34 or 86 will be opened until the other is closed, and the bore for the valve 32 is also made of such length that the valve will not be jammed in case the governor-belt slips off, which would allow the valve to drop.

In the operation should the engine run belowacertain desired speed the gOVGIIiOtll will cause an upward movement of the valve 32, which willopen the valve 2% and permit steam to pass to the under side of the piston 16, and this steam will force said piston upward until the cross-head reaches the cross-bar 26. hen said cross-bar is in its extreme upper position, the slide-valve will be moved its extreme distance, thus fully opening the ports leading to the engine-cylinder. By moving the cross-bar 26 downward the upward movement of the piston 16 will of course be limited, and consequently the throw of the slidevalve will be lessened. Of course while the engine is running the cut-off cylinder will be oscillated from the eccentric connection to the engine-shaft, and the said cut-off device is therefore practically a portion of the cocentric connection between the engine and the slide-valve. Should the engine reach a point above a desired speed, the outward movements of the governor-balls 44 will force the arm 42 downward, .moving the valve 32 down to close the port 34: and open the exhaust-port 36. Then the steam will pass out from underneath the piston 16, which will be forced downward by the spring 39, as before mentioned.

Having thus described my invention, I claim as new and desire to secure by Letters Patent 1. In combination with an engine, a swinging cylinder, an eccentric connection between said cylinder and the engine-shaft, a piston in the cylinder, a connection between said piston and the engine slide-valve, and means for automatically controlling the admission of a motive agent into said cylinder below the piston.

2. The combination with an engine, of a cylinder mounted to swing thereon, an eccentric connection between said cylinder and the engine-shaft, a piston operating in the cylinder, a connection between said piston and the slide-valve of the engine, and means controlled by the engine-governor for admitting and exhausting steam to the cylinder.

3. The combination with an engine, of a cylinder mounted to swing thereon, an eccentric connection between said cylinder and the engine-shaft, guides extended upward from the cylinder, a cross-head mounted to slide on said guides, a piston in the cylinder and having its stem connected to said cross-head, a connection between said cross-head and the slide-valve of the engine, and means for automatically controlling the inlet and exhaust of steam to the cylinder.

4. The combination with an engine, of a cylinder, a bracket extended from the bed of the engine, trunnions on said cylinder having bearings in said bracket, one of said trunnions being provided with a port, a port leading from the first-named port through the Wall of the cylinder, and communicating with the lower portion thereof, a piston operating in the cylinder, a connection between said piston and the valve of the engine, a valve-casing having port communication with the steamchest of the engine and also having communication with said ported trunnion, an exhaustport leading through the casing and having connection with a pipe providing comm unication with the ported trunnion, a valve mounted to slide in said casing and having an annular port for controlling the supply-port in the casing, and a connection between said valve and the governor of the engine.

5. The combination with an engine, of a bracket on the bed thereof and having an opening, a cylinder extended through said opening, trunnions on said cylinder having bearings in the bracket, an eccentric connection between said cylinder and the engineshaft, guidesextended upward from the cylinder, a stop-bar adjustable along said guides, a cross-head movable on the guides, a piston in the cylinder having connection with said cross-head, a connection between said crosshead and the slide-valve of the engine, and means for controlling'the admission of motive agent to the under side of said piston and for controlling the exhaust of the motive agent.

6. The combination with an engine, of a cylinder mounted to swing thereon, an eccentric on the shaft of the engine, a rod connection between said eccentric and the cylinder, a piston operating in the cylinder, a connec tion between said piston and the slide-valve of the engine, a valve-casing communicating with the steam-chest of the engine, said casing having a transverse supply-port and a transverse exhaust-port, the said ports having communication with the interior of the cylinder at the lower end, a piston in the easing and having a port for controlling the supply-port in the casing, a vertically-movable governor-rod on the engine, and an arm connection between said rod and the stem of said valve.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

JOHN LAWRENCE WHEELER.

Witnesses:

R. DEMINGS, JAS. S. MULVEY.

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