Nippon Thermostat Co., Ltd.

Asahi Kasei Microdevices Corporation

Mitsuhiro Sano

Daisuke Tsukamoto

Norio Suda

Masanori Takahashi

Hiroshi Suda

Masahiro Aburakawa

Yasuharu Uomori

Hidetoshi Sasaki

Hiroshi Morozumi

There is provided a switched capacitor circuit and a pipeline A/D converter which are capable of suppressing electric power from being increased by utilizing a level-shift capacitor, even in a case where the switched capacitor circuit and the pipeline A/D converter are configured by utilizing a CLS technique. In the estimate phase, the capacitor Cc(level shift capacitor) is connected between the output terminal of the operational amplifier AMPand the inverting input terminal of the operational amplifier AMP, so as to sample the output from the operational amplifier AMP, and also to compensate the phase of the operational amplifier AMP. Additionally, in the level shift phase, the capacitor Ccis connected between the output terminal of the operational amplifierand the output terminal Vb, so as to be used to level-shift the output of the operational amplifier AMP. Thereby, the load (the capacitance of the capacitors Ccand Cc) on the operational amplifier AMPis reduced, thereby reducing the electric power of the switched capacitor circuit

Switched capacitor circuit and pipeline A/D converter

An electronically controlled thermostat control method is obtained which makes it possible to eliminate the response delay from the time that the required cooling water temperature is set to the time that the actual cooling water temperature reaches the set water temperature by controlling the flow rate, and to realize high cooling water temperature tracking characteristics with a high degree of precision at a low cost. The method of the present invention is characterized in that in an electronically controlled thermostat which is used to control the cooling water temperature of an engine, and which comprises an actuator that can arbitrarily vary the degree of valve opening without depending only on the actual cooling water temperature, the actuator is controlled by the control controller, which has means for calculating the elapsed time from the powering of the actuator to the variation of the water temperature for predicting the water temperature after the elapsed time when the cooling water temperature is controlled to an arbitrarily set water temperature, and the actuator is controlled in advance in accordance with the above-described predicted water temperature.

Method of controlling electronic controlled thermostat

A control method for an electronically controlled thermostat includes that an actuator is used for cooling-water control of an internal combustion engine and the actuator is capable of optionally varying the valve-opening ratio. An engine control unit computes a target temperature by means of various engine parameters and distributes the power distribution amount required to operate the actuator so that the cooling water temperature reaches the target temperature. The power distribution amount distributed to the actuator is determined by monitoring only the actual water temperature of the cooling water.

Control method for electronically controlled thermostat

A method for controlling an electronically controlled thermostat provided in a cooling system of an internal combustion engine includes predicting a thermal radiation amount of a radiator when a water temperature of engine cooling water is stabilized at a second set temperature or at a first set temperature without detecting the water temperature not to cause temperature hunting, when the water temperature is controlled from a first set temperature to the second set temperature lower than the first set temperature or from the second set temperature to the first set temperature. The electronically controlled thermostat is controlled in accordance with the predicted thermal radiation amount.

Control method of electronic control thermostat

Cooling controller for internal-combustion engine

A system is provided wherein temperature conduction upon the changing of temperature of cooling water in an engine is forecast, and achievement of a cooling control system with an improved life and reliability and a reduction in cost results therefrom. A butterfly valve for regulating the flow of cooling water is rotatably controlled through a DC motor, a clutch mechanism,and a deceleration mechanism,so as to cool the engine at an appropriate temperature. A PWM signal generated by a quick response control and a PI control on the basis of at least load information of the engine is supplied to the DC motor,from ECU, whereby the butterfly valve,is rotatably controlled. A butterfly valve adjusting the flow of cooling water is controlled with the degree of valve opening by a thermo-element enclosing a thermal expansive body such as wax. A PTC heater is placed in proximity with the thermo-element, and supplied with current for heating on the basis of operation parameters of an engine to control the cooling efficiency of the cooling water. As a consequence, the characteristics of the butterfly valve which is capable of extremely decreasing rotation torque for adjusting the flow of the cooling water is used, so that mechanical stress can be reduced, resulting in improved life and reliability.

Cooling control system and cooling control method for engine

An object of the present invention is to provide a thermostat device which ensures a smooth slide without damaging the slide function by immersion of a cooling liquid, increase flexibility of a circulation channel design by miniaturization, and materializes a hand-operated opening and closing of a valve. In order to solve the problems, the thermostat device,in which a heat responding element (wax,) to expand and shrink by sensing the heating or cooling of the circulating liquid in the circulation channel, is embedded, a sliding member (piston rod,) is slid in accordance with volume changes caused by the expansion and shrinkage of the expansion element to open and close the valve body, is structured that a sensor case,which embeds the responding element is placed in the circulation channel of the circulating liquid, and the sliding member is placed outside of the circulation channel of the circulating liquid.

Thermostat device

Cooling control apparatus and cooling control method for internal

A cooling control system by which an internal combustion engine is prevented from overheating, and a fail-safe function exerts its effect. A butterfly valve 34b for regulating the flow of cooling water is rotated by a motor 31, a clutch mechanism 32, and a speed reduction mechanism 33, thereby cooling the engine to be at the most suitable temperature for driving. The aforesaid butterfly valve 34b is given momentum in a direction to open the valve 34b by a return spring 34e. For example, an angle sensor 34g for detecting the rotational angle of the butterfly valve 34b is included. In a computing unit, when it is determined that an abnormality occurs from the relationship between the data from an encode 34g and the temperature of the cooling water, the clutch mechanism 32 is released, and the butterfly valve 34b is automatically opened. Accordingly the engine is prevented form overheating.

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Tokyo, Japan

Mitsuhiro Sano