Vehicle-heating system employing a critical point heat pipe

Claim 3

In a system employing a heat pipe for thermally coupling a heat source to a heat sink and for exchanging heat between said heat source and said heat sink only when the temperature of said heat sink is different from a desired reference temperature, the improvement comprising: a. a vaporizable working fluid carried by said heat pipe means having a critical point temperature substantially corresponding to the desired reference temperature for transporting heat from said heat source to said heat sink by means of said heat pipe when the temperature of said heat sink is below said reference temperature, and for automatically terminating heat exchange when the temperature of said heat sink reaches said reference temperature, said automatic termination of heat exchange being the direct result of the properties of said heat pipe working fluid.

Claim 4

In a system employing a heat pipe for thermally coupling a heat source to a heat sink and for exchanging heat between said heat source and said heat sink only when the temperature of said heat sink is different from a desired reference temperature, the improvement comprising: a. a vaporizable working fluid carried by said heat pipe means having a critical point temperature substantially corresponding to the desired reference temperature for transporting heat from said heat source to said heat sink by means of said heat pipe when the temperature of said heat sink is below said reference temperature, and for automatically terminating heat exchange when the temperature of said heat sink reaches said reference temperature, said automatic termination of heat exchange being the direct result of the properties of said heat pipe working fluid.

Claim 5

An improved automotive heating system including a passenger compartment and an internal combustion engine, said system comprising: a. a heat exchanger, b. means for circulating compartment air through said heat exchanger, c. means for directing engine coolant from said internal combustion engine to said heat exchanger for heating said circulated air under normal operating conditions, d. heat pipe means thermally coupling said engine exhaust gases and said circulated air downstream of said heat exchanger, and e. a vaporizable working fluid carried by said heat pipe means to transport heat from said exhaust gases to said circulated air and having a critical point temperature corresponding substantially to the normal operating Temperature of the engine coolant flowing through said heat exchanger, said heat pipe means for transporting heat from said heat source to said heat sink when the temperature of said heat sink is below said reference temperature and for automatically terminating heat exchange when the temperature of said heat sink reaches said reference temperature, said automatic termination of heat exchange being the direct result of the properties of said heat-pipe-working fluid.

Claim 6

An improved automotive heating system including a passenger compartment and an internal combustion engine, said system comprising: a. a heat exchanger, b. means for circulating compartment air through said heat exchanger, c. means for directing engine coolant from said internal combustion engine to said heat exchanger for heating said circulated air under normal operating conditions, d. heat pipe means thermally coupling said engine exhaust gases and said circulated air downstream of said heat exchanger, and e. a vaporizable working fluid carried by said heat pipe means to transport heat from said exhaust gases to said circulated air and having a critical point temperature corresponding substantially to the normal operating Temperature of the engine coolant flowing through said heat exchanger, said heat pipe means for transporting heat from said heat source to said heat sink when the temperature of said heat sink is below said reference temperature and for automatically terminating heat exchange when the temperature of said heat sink reaches said reference temperature, said automatic termination of heat exchange being the direct result of the properties of said heat-pipe-working fluid.

Claim 7

The heating system as claimed in claim 3 wherein the evaporator portion of said heat pipe means is operatively coupled to the exhaust manifold of the internal combustion engine and the condenser portion of said heat pipe means is located at the downstream side of said heat exchanger.

Claim 8

The system as claimed in claim 4 further including insulating means carried by said heat pipe means intermediate of the evaporator and condenser portions.

Claim 9

The system as claimed in claim 4 wherein said vaporizable working fluid comprises freon.

Claim 10

The system as claimed in claim 4 wherein said vaporizable working fluid comprises ammonia.

Claim 11

The system as claimed in claim 4 wherein said heat exchanger is positioned at a higher elevation than said engine exhaust manifold.

Claim 12

The system as claimed in claim 3 wherein said heat-pipe-working fluid comprises one material of the group consisting of ammonia and freon and said heat pipe means includes a heat pipe tube formed of one material of the group consisting of copper, nickel, stainless steel, and aluminum.