US2100783A - Exhaust valve for internal combustion engines - Google Patents

Description

Nov. 30, 1937. w. KOZLOWSKI EXHAUST VALVE FOR INTERNAL COMBUSTION ENGINES Filed May 6, 1936 IN "ENT OR W ladyslaw lfozlowsk Patented Nov. 30, 1937 UNITED STATES ExnAUs'r VALVE Foa INTERNAL COM- BUSTION ENGINES Wladyslaw Kozlowski, Ton-ington, Conn.

Application May 6, 1936, Serial No. 78,175

2 Claims.

This invention relates to internal combustion engines, and more particularly to improvements in exhaust valves for engines of this type.

The exhaust valve mechanism of an internal combustion engine is subjected to the action of the extremely hot exhaust gases resulting in the deposition of carbon therefrom on the valve stem. This produces friction between the stem and its guide resulting in sticky valves and causing rapid burning, pitting, and wiredrawing of the parts of the exhaust valve, thereby seriously interfering with the eflicient operation of the valve. Various constructions of valves havebeen suggested to overcome these disadvantages and detrimental results, but these have not proven eflective, particularly on modern engines operating at high speed and under high compression.

One object of the present invention is to provide a new and improved valve structure whereby the deposit of carbon on the valve stem will be reduced to a minimum, thus reducing the burning, pitting, and wiredrawing of the valve parts.

Another object is to provide an exhaust valve of the above nature having an attachment whereby the exhaust gases will be outwardly deflected upon entering the exhaust chamber and prevented from impinging upon the valve stem.

A further object is to provide an exhaust valve attachment of the above nature which will be simple in construction, inexpensive to manufacture, readily manipulated, compact, and very efficient and durable in use.

With these and other objects in view, there has been illustrated on the accompanying drawing one form in which the invention may be conveniently embodied in practice.

In the drawing:

Fig. 1 is a sectional view of the cylinder and exhaust chamber of an internal combustion engine, illustrating an exhaust valve upon which the present invention has been installed, and indicating how the hot gases are deflected from the valve stem.

Fig. 2 is a longitudinal sectional view of a valve head, valve stem, and exhaust gas deflector embodying the features of thisinvention.

Fig. 3 is a side view of the valve stem and gas deflector assembly.

Fig. 4 is a detail view of deflector removed.

Fig. 5 is a sectional view of shown separately.

This invention contemplates the provision of a tubular shield or protector surrounding the upper portion of an exhaust valve stem adapted to outa valve stem with the the gas deflector wardly deflect the exhausting gases, and thus prevent the deposition of carbon upon the exposed portion of the valve stem.

Referring now to the drawing in which like reference numerals denote corresponding parts throughout the several views, the numeral i0 indicates a cylinder, containing the usual reciprocating piston H (see Fig. 1) in connection with an upper exhaust passageway l2, which in turn leads to an exhaust chamber I3 connected to an exhaust manifold M. A beveled valve seat 15 is provided, upon which a valve head I6 is adapted to seat in a wall l1 separating the passageway l2 and the chamber 13. An exhaust valve stem I8 is guided in its reciprocating movements by a tubular guide IB' having a beveled upper end In order to deflect the exhaust gases away from the valve stem l8 and the guide l9, provision is made of a tubular tapered frusto-conical member 20, preferably shrunk on said stem i8, and having its smaller end at the top abutting a shoulder 2| formed upon the stem' it directly beneath the valve head l6 and connected to said head by a concave annular section 20a. By means of this construction, the exhaust gases from the cylinder l0 will be laterally diverted by the tapered deflecting member 20 and prevented from directly striking the exposed stem l8 and the top of the guide l9 as said gases flow through the exhaust chamber iii. The direction of flow and the path of such gases is indicated by the arrows in Fig. 1.

The deflector member 20 is preferably countersunk at its large diameter lower end 22 as indicated at 23, the angle of the countersink substantially corresponding to the angle of the bevel l9a at the top of the guide l9. It will thus be seen that the countersink 23 in the lower end of the deflector member 20 acts as a cover or shield for the top of the guide i9.

Due to the tapered shape of the deflecting member 20 upon which the exhaust gases impinge, they will be deflected away from the stem l8 and. the guide l9, thus preventing the deposition of carbon on the valve stem l8 and the consequent pitting or burning of the valve and its seat.

One advantage of employing a tapered outwardly andflownwardly deflecting member 20 with its largest end at the bottom is that the material thereof is of maximum thickness at the point where-the greater part of the gases impinge, this point being in line with the flow of the gas through the valve, thus insuring long life for the deflecting member 20.

While there has been disclosed in this specification one form in which the invention may be embodied, it is to be understood that the invention is not to be limited to the specific disclosure but may be modified and embodied in various other forms without departing from its spirit. In short, the invention includes all the modifications and embodiments coming within the scope of the following claims.

Having thus fully described the invention, what is claimed as new, and for which it is desired to secure Letters Patent, is:

1. In an exhaust valve, a valve head having a depending stem, a guide in which said stem reciprocates, said guide having a beveled top, a valve seat to receive said head when the valve is closed, and a frusto-conical downwardly diverging thick metal defiecting member tightly embracing said stem and having its upper small diameter end below and spaced from said head, said deflecting member having a short conical countersink in its base to loosely fit over the beveled top of said guide only at the bottom of the stroke of said valve head.

2. In an exhaust valve, a valve head having a stem, a tubular guide having a beveled top edge in which said stem reciprocates, a valve seat to receive said head when the valve is closed, a shoulder on said stem below and spaced from said head, and a short thick frusto-conical member tightly embracing said stem with its small diameter end abutting said shoulder, the lower end of said conical member being countersunk to loosely embrace the top beveled edge of said guide at the bottom of the stroke of said valve, said shoulder serving to position said member at the proper distance below said head.

WLADYSLAW KOZLOWSKI.

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