Abstract: A coolant circulation circuit of an internal combustion engine includes a heat accumulation tank having a heat insulating structure and a heater core for heating air for heating a compartment in the vehicle. High temperature coolant is reserved in the heat accumulation tank even when the engine is stopped. An intake air heat exchanger is disposed in the circuit on the downstream side of the heater core, and high temperature coolant can effectively heat the intake air. An engine lubricating oil heat exchanger and a transmission operating oil heat exchanger are arranged in the circuit on the downstream side of the intake air heat exchanger. Intake air, engine lubricating oil and transmission operating oils are suitably heated during warm-up of the engine to thereby improve fuel economy and reduce exhaust gas pollution.

Abstract: According to the present invention, coolant temperature Tw after an engine has stopped is detected by a coolant-temperature sensor. An amount of temperature rise .DELTA.Tw is calculated from a temperature difference between the present coolant temperature (Tw) and the previous coolant temperature (Tw-1). It is determined on the basis of the amount of temperature rise .DELTA.Tw whether coolant temperature after the engine has stopped has reached a substantially maximum temperature. Specifically, the amount of temperature rise .DELTA.Tw and a set amount of temperature rise .DELTA.T which has been set in advance are compared, and in a case where .DELTA.Tw>.DELTA.T, temperature rise is large and coolant temperature is still rising. Therefore, recovery of coolant is not performed. When .DELTA.Tw.ltoreq..DELTA.T, the amount of temperature rise is small and the present temperature is substantially the maximum temperature, and an electrical pump is operated to recover coolant.

Abstract: An engine warming-up apparatus includes a reserve tank integrally provided with a heat insulating device provided in a coolant circuit in which coolant for cooling an internal combustion engine flows. The reserve tank includes a reserve tank body secured to the top of a tank base, a connection pipe for connecting between an outlet pipe of the tank base and the inside of the reserve tank body, and a heat insulating device located-between the tank base and the reserve tank body and covered by the reserve tank body. A degassing pipe is provided at the top of the heat insulating device so as to communicate between the inside of the heat insulating device and the inside of the reserve tank body. A water filling opening of a hot water supply pipe is formed around the top of the inside space of the heat insulating device. In this way, a high temperature coolant is firstly supplied at a cold start, thereby improving warming up performance.

Abstract: An oil cooler includes a heat exchanging core 40 which includes a stack of heat exchanging plates 40. Each of the heat exchanging plates 40 includes a first set of openings 61 and 62 and a second set of openings 65, 66 and 67. The openings 65, 66 and 67 in the second set construct rows which are spaced along the width W of the plates 40. The openings between the first and second sets are alternately arranged along a direction of the width W of the plates. The openings 61 and 62 in the first set are symmetrical about a central axis X--X, while the openings 65, 66 or 67 in each row are asymmetric about the axis X--X.

Abstract: A cooling apparatus for cooling an internal combustion engine having a coolant passing through the engine is provided. A heat exchanger performs a heat-energy exchange and a heat exchanger bypass passage prevents part of the coolant flowing out from the engine from flowing into the heat exchanger. A coolant combination device forms a mix of coolant which flows in a passage bypassing a thermostat with coolant which flows in a passage through the thermostat, while a flow rate ratio adjusting valve continuously adjusts the ratio of the flow rate of the part of the coolant which bypasses the thermostat to the part of the coolant which passes through the thermostat in accordance with a temperature of the coolant. Accordingly, the higher the temperature is, the larger the ratio is. Moreover, the temperature is controlled in accordance with a load of the engine so that the larger the load is, the higher the temperature is.

Abstract: An heat exchanger transfers the heat from engine oil passing through a plurality of tube members to engine coolant within a housing for cooling the engine oil. The tube members are arranged within the housing in groups with the tube members in each group being aligned radially to form a fan shaped core. The cores are arranged circularly, so that the effective surface of the tube members through which the heat of the engine oil therewithin transfers to the engine coolant outside of the tube members becomes maximized.

Abstract: A cooler for engine lubricant oil is formed by a stack of heat exchanger modules each defining therein a first space for engine cooling water. A second space is defined between each adjacent pair of modules. The first spaces in respective modules are communicated with each other by water inlets and outlets. The second spaces are communicated with each other by openings. One of the outermost modules is sealingly connected to a part of a lubricant circuit of the engine while the other outermost module is sealingly connected with an oil filter so that hot lubricant oil from the engine flows through the second spaces in the stack of modules into the oil filter in heat exchange relationship with engine cooling water flowing through the first spaces in respective modules. The oil filter is communicated with another part of lubricant circuit for the recirculation of cleaned oil back into the engine.

Abstract: A heat exchanger apparatus includes a heat exchanger constituted by a multiplicity of heat exchanger units laminated one upon another and a filter having first and second filter elements for removing any unnecessary substance mixed into a working fluid. A fixing member (bolt) is disposed such as to extent through the heat exchanger so that the heat exchanger and the filter are integrally secured to each other. The heat exchanger is provided therein with a communicating passage communicated with the upstream side of the first and second filter elements, a main flow passage communicated with the downstream side of the first filter element, and a subsidiary flow passage communicated with the downstream side of the second filter element.

Abstract: Each of heat exchanging units which constitute a heat exchanger is composed of a first plate and a second plate respectively provided with a through hole, an inlet hole and a communication hole and formed with crowns adapted to form a space through which a second fluid flows, a collar and a ring, both surfaces of which are placed in contact with inner surfaces of both first and second plates, are interposed between the first and second plates to form a space through which a first fluid flows. The collar is disposed being axially aligned with a flange portion of the through bolt extending through the heat exchanging units whereby the load resistance of the heat exchanging units can be increased. Moreover, with this arrangement, the heat exchanging units may be easily stacked.