US2211013A - Valve mechanism - Google Patents

Description

Aug. 13, 1940. 2.21 1,013

H. L. HOSTERMAN VALVE MECHANISM Filed 001;. 4, 1938 2 Sheets-Sheet l 6' INVENTOR.

v lfi y ATTORNEY.

Aug. 13,1940- H. L. HOSTERMAN 221L013 VALVE MECHANISM Filed Oct. 4, 1938 2 Sheets-Sheet 2 INVENTOR. flak/y 1., floxfe/vzra/z ATTORNEYJ;

Patented Aug. 13, 1940 PATENT. OFFICE VALVE MEGHANISIVI Harry L. Hosterrnan, Akron, Ohio, assignor of one-fourth toGeorge W. Perks and one-fourth to Donald Glottwald, Akron, Ohio Application October 4,

I j '7 C laims.

This invention relates to valve mechanism for use in internal combustion engines and is more particularly directed to mechanism of the type.

employing a' single valve through which the intake gas is passed to the cylinder and the exhaust gas removed therefrom.

Mechanisms of this general type are very old and it has frequently been'proposed to provide a single poppet valve providing access to the cylinder for both the exhaust and intake gases and combined with a secondvalve to alternately: effect a fuel intake or fuel discharge as desired. These prior mechanisms have been subjectedto the disadvantage that both the intake and exe' haust lines were open at-the same time for an appreciable and uncontrolled period during operation- This time period was sufiicient to blow exhaust gas back into the intake line and nullify the otherwise efficient characteristics of the design. In some cases the hot exhaust gas would ignite the intake gas and pre-explode the fuel before it had passed beyond the second valve. With mechanisms of this type, it has heretofore not been possible to control the degree of overlap between the period the exhaust valve is open and the period the intake valve is open. Expressed in another way,'the inertia and speed limitations in valve mechanisms, from a practical standpoint, prevent the instantaneous opening of a valve. Therefore the valve must open as a result of appreciable movement.

I have found that if I provide a sleeve valve which may simultaneously commence to move to seal one port and at the same time continue to as eal the other port until such time as the operating characteristics of the engine demand that the latter port be opened I caneffectuallyemploy a single poppet valve to function as both" intake and exhaust to the cylinder. In certain cases it is desirable to maintain one port entirely closed during the period the other port isopen and in other engines. with other operating characteristics, what I term a controlled degree of overlap of valve opening should be employed to allow both ports to be open during a short period of the engine cycle. This period. should not exceed 60 degrees of crankshaft rotation or 30 degrees of camshaft rotation, the latter shaft rotating at one-half thecrankshaft speed.

-The cardinal object ofthis invention has been to provide a valve mechanism for internal vcombusticn engines which will permit of a large area of cylinder valve with respect to a given cylinder 55 diameter than has heretofore been possible ,and

1. 38, Serial or 233,323

(01, 123.79) I a .thus to improve the volumetric efficiency of the en ine."

An additional object of my invention has been to overcome the operating disadvantages with former related constructions by providing a valve 1 mechanism with a controlled degree of overlap ,for the most efficient operation of the engine by which there isno possibility of both the intake and exhaust lines being open to the cylinder bey;ond a desired time; As a related object of my invention I amgenabled by the valve mechanism itself to time the intervening period between closing the exhaust line and opening the intake line. 3

To the accomplishment of the foregoing and related ends, said invention; then, consists of the means hereinafter fully described and particularly pointed out in the claims; the annexed drawings and the following description setting forth in detail certain structure embodying the invengo tion, such disclosed means constituting, however, but one ofvarious mechanical means inwhich the principle of the invention may be used.

In said annexed drawings:

Figs; 1, 2, 3-and 4 are similar sections through my improved valve mechanism showing respectively the position of the parts during the power, exhaust, intake and compression strokes; and V Fig. 5 is a section through Fig. 2, as indicated by the lines 5-5 thereon. g

' Referring now to the drawings; I provide a cylinder block I0 in which is formed one or more cylinders H, accommodating a-piston 12, to which 7 is connected the usual connecting rod M for engagement with the crankshaft. .A head I5 is i-35 bolted to the block-I0 and supports the valve mechanism hereafter described. 7

The head it is formed with an intake conduit H and an exhaust conduit l8 opening into a valve casing 28, which communicates with an 4o explosion-chamber 22 in communication with the .main cylinder H.

A poppet valve 25 seats against the .cylinder head at .26 and is provided with a stem 23slidably receivedin a core 38. as-a valve stem guide, includes a head portion ti-by which the same is secured to-the head withinthe'valve casing 20 and in position to effective-j lyseal the same at its ,upper end. An annular boss 33, formed as indicated in the drawings, on 50 the lower portion of thecore coacts with the valve casing wall to form a sliding valve seat as hereaftendescribed. x

To seal the intake conduitl'l from the exhaust conduit I8, a sleeve valve is provided recip- .55

The core which functions rocable between the boss 33 and the adjacent casing side wall. As best shown in Figs. 2 and 3, the sleeve cross-section is of such length and configuration that during its downward movement to seal the exhaust conduit it will maintain the passage from the intake conduit closed for the desired period of time. sleeve by which this is accomplished .may be varied in length toprovide some latitude between the final sealing of the exhaust conduit and the instant at which the intake is opened. This feature, which I call the controlled degree of overlap, allows the original design of the mechanism for a given result independent of adjustment of the camshafts.

During the exhaust stroke, as shown in Fig. 2, the sleeve is in its upper position and the exhaust gases pass around the open poppet valve and out through the exhaust conduit I8. At the conclusion of the exhaust stroke the sleeve 35 is lowered and seals off the exhaust. The sleeve proceeds on downwardly, as shown in Fig. 3, to open a port between its upper portion and the annular boss 33. Thus intake gas may be sucked past the sleeve and past the poppet valve'into the explosion chamber of the cylinder. At the termination of this operation the poppet valve closes and the piston 42 rises to effect the compression stroke, which is immediately followed by ignition and the power stroke in a manner well known in the art and not further described.

To actuate the sleeve 35 the mechanism shown in Fig. is provided. This consists of a pair of upwardly extending ears 33 on opposite sides of the sleeve and extending above the spring cover 40, which surrounds the valve casing 20. Each ear is provided with a horizontal lug 42 to position the compression spring 45 between it and a shoulder on top of the cylinder head. The normal tendency of the springs 45 to retain the sleeve in the upper position shown in Fig. 1 is counteracted by cams 41 on a camshaft 50 which is driven, as well understood, in timed synchronism with the crankshaft. To actuate the poppet valve, a cam 52 is provided, adapted to ride over a cap 53 bearing on top of the valve stem and guided in a guideway 54 of the valve cap 40. A spring ring 55 is secured to the upper end of the valve stem and a compression spring 5'! is interposed between the ring and the portion 3| of the core 30.

From the present mechanism just described, it will be apparent that the sleeve and poppet valve are normally retained in the upper positions shown in Fig. 1, due to the action of their respective springs and that the downward motion of each valve member is effected by the corresponding cams on the cam-shaft 50.

From the foregoing description it will be apparent that I have provided an improved valve mechanism by which a single valve opens into the power cylinder and when open serves as a passage for both intake and exhaust gases and improves the volumetric efficiency of the engine. The continually cooling efiect of intermittent charges of intake gas largely nullifies the harmful effects of the hot exhaust gas and also prevents the precipitation of carbon at the valve seat. The controlled degree of overlap in the sleeve 35 permits entirely sealing either the intake or exhaust conduit to the poppet valve before the other passage is opened.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the structure herein disclosed, provided the means The depth of the valve stated by any of the following claims or the equivalent of such stated means be employed.

I therefore particularly point out and distinctly claim as my invention:

1. In an explosion engine, a cylinder structure, a piston in said cylinder, a valve casing in communication with said cylinder and concentric therewith,.a valve seat in said piston cylinder, acore in said valve casing with a valve stem guide coincident with the valve axis, a valve with a stem slideable in said guide to coact with said seat and seal the cylinders and easing from each other, resilient means to normally seat said valve, an intake and an exhaust conduit each opening to said valve casing, a sleeve slidable in said valve casing between the core and side wall portion to control passage of gas between the intake conduit and the valve casing and between said exhaust conduit and said valve casing, said sleeve acting to completely seal one conduit from said valve casing before openingthe other conduit to said valve casing, and means to actuate said valve and said sleeve.

2. In a valve mechanism for an internal combustion engine, a cylinder, a poppet valveand a seat therefor in communication with said cylinder and a casing, a sleeve valve mounted to reciprocate coaxially with the poppet valve in said casing, ,a core in said casing an exhaust conduit and an intake conduit in communication with said casing, one of said conduits opening past said sleeve valve axially of said cylinder, and the other opening transversely thereof in a region closely adjacent said first opening, said sleeve valve coacting with said core to control said axial opening with the inner axial face thereof and to control said transverse opening with the outer axial face thereof, means to reciprocate said sleeve valve to alternately open said intake and said exhaust to effect a passage of intake and exhaust gas past said poppet valve and seat, said sleeve formed to seal said intakeconduit in a region closely adjacent said exhaust conduit to prevent the accumulation of an appreciable volume of exhaust gas in said casing after said exhaust conduit is closed.

3. In an explosion engine, a cylinder block having a cylinder, a valve casing in communication therewith, said casing having two ports opening therein, a stationary core in said casing, a sleeve valve in said casing, said sleeve valve being adapted for coaction with said core for sealing one of said portsand having a surface adapted to cover the other of said ports.

4. In an overhead valve internal combustion engine, the combination of a valve casing having two ports and an aperture opening therein, a core projecting into said casing, a valve member slidable within the core for closing said aperture, a sleeve having an outer axial surface adapted for covering one of said ports and an inner axial surface adapted for coaction with said core for controlling the other of said ports.

5. In a valve mechanism, the combination of a valve casing having an opening for communication with a power cylinder, a conduit opening into said casing, a core projecting into said casing, a valve member slidable within the core for closing said opening, a sleeve in sliding engagement with said casing and said core, means for intermittently breaking the engagement between said sleeve and said core whereby said conduit and said opening communicate through the opening of said sleeve.

6. In a valve mechanism, a valve casing having therein two openings, a sleeve slidable in said casing between said openings; a poppet valve member associated with the sleeve, means for sealing communication between the valve member and the sleeve and means for actuating said sleeve whereby said openings are intermittently in communication with each other.

'7. In an explosion engine, a cylinder structure, a cylindrical valve casing, a valve seat in communication with said cylinder and said casing,

10 a core in said casing having a valve stem guide therein, a valve With a stem slideable in said guide for coaction with said valve seat for sealing said valve casing from said cylinder, an intake conduit and an exhaust conduit each opening in said valve casing, a sleeve valve for covering one of said conduits, the other of said conduits being controlled by coaction between said casing, sleeve valve and core, and means for actuating said valves.

HARRY L. I-IOSTERMAN.

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