Auxiliary electric heating system for internal combustion engine powered vehicles

Claim 1

In an internal combustion engine vehicle coolant flow system which includes an internal combustion engine, coolant circulator pump for pumping coolant heated by the engine from the engine, a heating radiator for transferring heat contained in the coolant to an enclosed area of the vehicle, electric blower means for increasing the rate of heat transfer by the radiator to the enclosed area and a first piping by which the coolant flow is established from the coolant circulator pump to the radiator and a second piping by which the coolant flow is established from the radiator to the engine, the improvement comprising an auxiliary heating system including: a electric pump, connected at its input side to the second piping for receiving coolant fluid therefrom, a check valve having an input and an output end, a conduit for connecting said check valve to the output end of said electric pump, said check valve being oriented so that its input end receives fluid from the electric pump for flow therethrough to its output end and that it will prevent fluid flow back through it to the electric pump, a first normally open electrically controlled valve single path connected at one end to the check valve output and at the other end to the first piping, a second normally open electrically controlled valve single path connected at one end to the check valve output and at the other end to the first piping at a point spaced from the connection of said first valve with the first piping, there being no direct through connection in the first piping between where the two single path valves join the piping so that fluid flowing from the coolant circulator pump to the radiator as recited earlier must pass serially through the valve in flowing through the first piping, said first and second valves normally being open to fluid flow, and being closed to interrupt fluid flow when electrically excited, a electric heating element, mounted sealingly in the conduit and adapted for receiving electrical current from without the conduit, for providing heat to the coolant flowing therethrough, a temperature sensing element connected for interrupting electrical current flow through the electric heating element when a predetermined coolant temperature in the auxiliary heating system is reached, mounted for sensing coolant temperature in said auxiliary heating system, means for receiving a first electrical current and, means for switching the first electrical current on or off to the electric heating element, means for selectively switching the first electrical current through the normally open valves and through the electric pump in any order of options, among options comprising; (a) no current through the electric pump and no current through either valve so that they remain open for permitting unimpeded coolant flow through the internal combustion engine coolant flow system by the coolant circulator pump, (b) current through the electric pump yet not through either valve so that coolant driven through the check valve by the electric pump takes two paths, and passes through the first valve then the engine by way of the first piping and returns to the electric pump by way of the second piping, while it sumultaneously passes through the second valve, then the radiator by way of the first piping after which it returns to the electric pump by way of the second piping, (c) current through the electric pump and the second valve to exclusion of the first valve so that coolant driven through the check valve by the electric pump passes through the first valve then the engine by way of the first piping and returns to the electric pump by way of the second piping and is restricted from flow to and through the radiator by the closed, second valve, and (d) current through the electric pump and the first valve to exclusion of the second valve so that coolant driven through the check valve by the electric pump passes through the second valve, then the radiator by way of the first piping after which it returns to the electric pump by way of the second piping, and is retricted from flow to the engine by the closed first valve.