Hollow Valve For An Engine

Abstract

The embodiments of the present invention comprise a coolant-free hollow valve with a cavity and a vacuum being enclosed in the cavity. The valve is used for an engine and one example of an engine is an internal combustion engine. The valve comprises a coolant-free hollow vacuum cavity to reduce the heat conduction such that the combustion heat is used to perform useful work to improve the efficiency of the engine. One embodiment of the present invention is a coolant-free valve with a hollow vacuum cavity and a thermal barrier coating being deposited onto part of the external surface of the valve that comes into contact with the combustion chamber of the engine.

Description

FIELD OF THE INVENTION[0001]This application relates generally to valves used in internal combustion engines. More specifically, this application describes a coolant-free hollow valve with a vacuum cavity.BACKGROUND OF THE INVENTION[0002]Valves are essential components of internal combustion engines to regulate the intake of fuel and air as well as the exhaust of the combustion products. An alternative name for the valves for internal combustion engines is poppet valves. As shown in FIG. 1A, a typical valve consists of a long valve stem 200 and a broad valve head 100. Combustion inside an engine produces heat and the hot gas reaches a high temperature to produce useful work such as propelling an automobile or rotating a generator to produce electricity. A surface 110 of the valve comes into contact with the combustion chamber and is exposed to high temperatures. In addition to the solid (cavity-free) valve schematically illustrated in FIG. 1A, there are hollow valves with cavities t...

AI Technical Summary

Benefits of technology

The present invention provides a coolant-free hollow valve in an engine that has better insulation properties. By removing the coolant and associated manufacturing steps, the valve is more cost-effective and flexible in manufacturing. Additionally, the valve head can be made of one heat-resistant material without any welding on its surface, reducing vulnerability to welding-induced failures. To further improve insulation, a thermal barrier coating is deposited onto the combustion-facing surface of the valve head.

Problems solved by technology

Because part of the heat inside the engine is extracted away by the valves instead of being used to do useful work, these valves have the negative effect of reducing the efficiency of the engine.

Even for these solid valves, the heat conduction from them amounts to a significant part of the heat loss of the engine and thus leads to reduced efficiency.

Even though the '822 patent recognized the benefits of insulation, the solutions are very complex and require several manufacturing steps to make the two-cavity valve, which may lead to prohibitive cost.

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