When the engine is stopped while the engine is warmed up, the cooling water in the engine stays therein without flowing out of the engine, and the cooling water in the radiator or the bypass passage is used for heating source for the heating operation. In this way, it is possible to heat the passenger compartment continuously even after the engine is stopped and to suppress the temperature of the cooling water from lowering to reduce the emission at restarting of the engine.
In a cooling water circuit system, cooling water pumped by a mechanically-driven first water pump circulates in a cooling water circuit, and flows through a radiator and a heater core in parallel in the cooling water circuit. An electrically-driven second water pump is disposed in the cooling water circuit at a position where cooling water to be supplied to the radiator from the first water pump and cooling water to be supplied to the heater core from the first water pump flow together. A check valve is provided in the cooling water circuit in parallel with the second water pump so that cooling water flows in one way from a water suction side of the second water pump toward a discharge side thereof. Thus, when the second water pump is operated, a total amount of cooling water pumped by the first water pump and the second water pump can flow through the radiator and the heater core. As a result, the cooling water circuit system can improve engine-cooling effect in the summer, while improving heating effect of a passenger compartment in the summer.
A check valve having a thermostat function is provided between an engine and a thermal storage tank that stores a portion of the coolant circulating in the engine. The check valve restricts the flow of the coolant from the engine to the thermal storage tank, and loosens the restriction when the temperature of the coolant increases. Through such operation of the check valve, the warm coolant is collected in the thermal storage tank and engine preheating may be performed before engine start. Thus, by providing between the engine and the thermal storage tank the check valve that operates in response to the temperature of the coolant, engine preheating can be accomplished with a simple structure and at a low cost, without using a three-way valve and performing an electrical valve switching control.
A hot coolant type heat accumulating apparatus for a hybrid vehicle is provided that includes an internal combustion engine having first and second coolant circulation systems through which a coolant is circulated using power from the engine, a heat accumulation tank that recovers, via part of the second coolant circulation system, some of the coolant that has been heated by the internal combustion engine, and stores that heated coolant, and a controller. This controller automatically shuts off the internal combustion engine when a predetermined shutoff condition has been fulfilled, circulates the coolant through the second coolant circulation system while the internal combustion engine is shutoff, and inhibits recovery of the hot coolant while the internal combustion engine is shutoff by automatic shutoff.
An engine control system for a hybrid vehicle having an internal combustion engine and an electric motor as driving force sources, for permitting stopping and restarting of the engine in accordance with predetermined drive conditions. The engine control system includes a fuel cutter for cutting fuel supply to the engine when the vehicle decelerates and an engine speed detector for detecting an engine speed. Stopping of the engine is initiated by cutting the fuel supply by the fuel cutter, and when the engine speed becomes equal to or lower than a predetermined speed, the engine is stopped by operating the motor as a generator and by cutting the fuel supply.
An apparatus for heating the interior compartment of a vehicle, the apparatus has a primary heating system, a secondary heating system and an operating system. The primary heating system receives and circulates an engine coolant through a heater core. The secondary heating system receives and circulates a gas, the secondary heating system heats the gas and circulates the heated gas through a heat exchanger. The operating system for operating the heating systems, the operating system receives a plurality of inputs and in response to the inputs the operating system determines which of the heating systems is to be activated in response to a heating request. The operating system also determines whether or not to deactivate one or both of the heating systems.
