Engine safety device responsive to abnormal oil pressure and coolant temperature conditions

Claim 1

A device for controlling the flow of fuel to an internal combustion engine in response to pressure conditions existing in a pressure-lubricating system of they type comprising a body having a main fuel passageway therein, fuel inlet and outlet ports communicating with said passageway and adapted to be connected to the fuel supply line of the engine, a valve in said passageway controlling the normal flow of fuel between said inlet and outlet ports, pressure-actuated means normally subject to a pressure equal to that of the lubricant in said lubricating system for maintaining said valve in open position as long as the pressure exerted on said means is at least equal to a predetermined value, means operable to close said valve when the pressure exerted on said pressure-actuated means drops below said predetermined value, and manually operable means for opening said valve to permit fuel to flow to the engine when the lubricant pressure exerted on said pressure actuated means is less than said predetermined value, wherein the improvement comprises: means independent of said manually operable means and operative when said valve closes automatically in response to a drop in pressure of the lubricant in said lubricating system for supplying sufficient fuel to the engine to keep it running at a reduced speed comprising a bypass fuel passageway in said body, bypassing the portion of said main passageway controlled by said valve, through which a limited amount of fuel may flow from the inlet port to the outlet port when said valve is closed, said bypass passageway being open at all times when the engine is running and of substantially smaller cross-sectional area than the orifice through which fuel normally flows between said inlet and outlet ports when the valve is open.

Claim 2

A device for controlling the flow of fuel to an internal combustion engine in response to pressure conditions existing in a pressure-lubricating system of they type comprising a body having a main fuel passageway therein, fuel inlet and outlet ports communicating with said passageway and adapted to be connected to the fuel supply line of the engine, a valve in said passageway controlling the normal flow of fuel between said inlet and outlet ports, pressure-actuated means normally subject to a pressure equal to that of the lubricant in said lubricating system for maintaining said valve in open position as long as the pressure exerted on said means is at least equal to a predetermined value, means operable to close said valve when the pressure exerted on said pressure-actuated means drops below said predetermined value, and manually operable means for opening said valve to permit fuel to flow to the engine when the lubricant pressure exerted on said pressure actuated means is less than said predetermined value, wherein the improvement comprises: means independent of said manually operable means and operative when said valve closes automatically in response to a drop in pressure of the lubricant in said lubricating system for supplying sufficient fuel to the engine to keep it running at a reduced speed comprising a bypass fuel passageway in said body, bypassing the portion of said main passageway controlled by said valve, through which a limited amount of fuel may flow from the inlet port to the outlet port when said valve is closed, said bypass passageway being open at all times when the engine is running and of substantially smaller cross-sectional area than the orifice through which fuel normally flows between said inlet and outlet ports when the valve is open.