Waste heat utilizing system

A waste heat utilizing system for an automotive vehicle having a water cool internal combustion engine comprising:

• a heater core for performing heat exchange between engine cooling water flowing out of the engine and air to be blown into a vehicle passenger room;
• a first fluid passage for connecting the heater core with the engine to form a closed fluid circuit, through which the engine cooling water flows from the engine to the heater core;
• a heat storage tank for storing the engine cooling water and keeping the heat thereof;
• a second fluid passage bifurcated from a bifurcating point of the first fluid passage at a downstream side of the heater core, and connected to the engine through the heat storage tank;
• a first pump provided in the first fluid passage for circulating the engine cooling water from the engine and back to the engine through the heater core and the bifurcating point, wherein the first pump is provided at a downstream side of the bifurcating point in the fluid flow, so that a negative pressure is generated in a portion of the first fluid passage between the bifurcating point and the first pump;
• and
• a second pump of an electrically operated type, provided in the second fluid passage for circulating the engine cooling water, so that the engine cooling water flows from the heat storage tank to the engine;
• wherein the heat storage tank comprises;
• a main tank body;
• a housing having a fluid flow-in passage through which the engine cooling water flows into the heat storage tank and a fluid flow-out passage through which the engine cooling water flows out of the heat storage tank;
• a check valve provided in the fluid flow-out passage for allowing the engine cooling water to flow only in a direction, which is a direction of the fluid flow caused by a pumping operation of the second pump;
• and
• an ON-OFF valve provided in the fluid flow-out passage in parallel with the check valve for opening and closing the fluid flow-out passage depending on a temperature of the engine cooling water.

A waste heat utilizing system for an automotive vehicle having a water cool internal combustion engine comprising:

• a main cooling circuit formed by the engine, a radiator, and a first pump, in which engine cooling water is circulated by an operation of the first pump;
• a hot water circuit formed by the engine, a heater core, and the first pump, so that the engine cooling water is circulated by the operation of the first pump, the hot water circuit having a bifurcating point so that the hot water circuit is divided into a first part having the heater core and a second part having the first pump;
• and
• a heat storing water circuit connected between the bifurcating point of the hot water circuit and the engine, and having a second pump and a heat storage tank, in which the engine cooling water is circulated by an operation of the second pump from and back to the engine through the heater core, the bifurcating point, the second pump and the heat storage tank, the engine cooling water being further circulated by the operation of the second pump through the second part of the hot water circuit and the heat storing water circuit.

A waste heat utilizing system for an automotive vehicle having a water cool internal combustion engine comprising:

• a main cooling circuit formed by the engine, a radiator, and a first pump, in which engine cooling water is circulated by an operation of the first pump;
• a hot water circuit formed by the engine, a heater core, and the first pump, so that the engine cooling water is circulated by the operation of the first pump, the hot water circuit having a bifurcating point so that the hot water circuit is divided into a first part having the heater core and a second part having the first pump;
• and
• a heat storing water circuit connected between the bifurcating point of the hot water circuit and the engine, and having a second pump and a heat storage tank, in which the engine cooling water stored in the heat storage tank is circulated by an operation of the second pump from and back to the heat storage tank through the engine, the heater core, and the bifurcating point, shortly before the engine operation will be started, so that the engine is warmed up,
• wherein a part of the engine cooling water is circulated by the operation of the first pump through the main cooling circuit when temperature of the engine cooling water is higher than a predetermined value, and
• another part of the engine cooling water is circulated at the same time by the operation of the first pump through the first part of the hot water circuit and the heat storing water circuit, so that the high temperature engine cooling water is stored in the heat storage tank.