Japan Electronic Control Systems Company, Limited

Sanden Corporation

Unisia Jecs Corporation

Masaru Kuribara

Kazumitsu Kobayashi

Syunji Komatsu

Toru Takeshita

Yoshiki Yuzuriha

Masamichi Imamura

Yuji Nakajima

Method and apparatus for detecting an insufficiency of refrigerant in an

The fuel character judging system has an electrical capacitance type sensor which outputs a first detection signal representative of a first character of a fuel mixture. A resistance type sensor outputs a second detection signal representative of a second character of the fuel mixture. A control unit stores first and second maps for a known fuel mixture having known first, second and third numbers corresponding to components of the known fuel mixture. The first map has a plurality of first characteristic lines which respectively correspond to a plurality of values of the first detection signal from the electrical capacitance type sensor. The second characteristic lines are plotted in accordance with the second signal from the resistance type sensor upon changing the known first number. One of the second characteristic lines in the second map is selected in accordance with the first detection signal from the electrical capacitance type sensor. The unknown first number is determined in accordance with the one second characteristic line selected and with the second detection signal for the unknown fuel mixture, from the resistance type sensor. A first characteristic line in the first map is selected in accordance with the determined first unknown number. The unknown second number is determined in accordance with the selected first characteristic line and with the first detection signal for the unknown fuel mixture, from the electrical capacitance type sensor. The unknown third number is determined according to the first and second determined unknown numbers.

Fuel character judging system

An air conditioning system including a refrigerant circulation route, a compressor, a condenser, an expansion valve, an evaporator and a pressure sensor for detecting pressure in the circulation route comprises a refrigerant phase detecter provided on the circulation route between the condenser and the evaporator where the refrigerant should be in a liquid phase for detecting whether the refrigerant is in a liquid phase or in a vapor phase and a control for determining whether the compressor is in a locked state in accordance with the signals from the refrigerant phase detecter and the pressure sensor. The air conditioning system can precisely determine and detect both compressor lock up and refrigerant leakage without providing a rotation detecting sensor for the compressor.

Sensor and control system for an automotive air conditioning system

Residual coolant sensor for air conditioning system

An air conditioning system including a refrigerant circulation route, a compressor, a condenser, an expansion valve, an evaporator and a pressure sensor for detecting pressure in the circulation route comprises a refrigerant phase detector provided on the circulation route between the condenser and the evaporator where the refrigerant should be in a liquid phase for detecting whether the refrigerant is in a liquid phase or in a vapor phase and a control for determining whether the compressor is in a locked state in accordance with the signals from the refrigerant phase detector and the pressure sensor. The air conditioning system can precisely determine and detect both compressor lock up and refrigerant leakage without providing a rotation detecting sensor for the compressor.

A refrigerant overcharge prevention system is applied to a refrigerant charging apparatus which has a refrigerant supply source and a refrigerant supply pipe connected to a refrigerant circuit of a cooling apparatus. The charging apparatus charges refrigerant into the refrigerant circuit while activating a compressor provided in the refrigerant circuit. The system comprises a refrigerant flow suppressing mechanism provided in the refrigerant supply pipe for preventing an excessive flow of refrigerant being charged, a refrigerant charge determining sensor provided in a high-pressure side path of the refrigerant circuit for determining whether the amount of charged refrigerant reaches a desired level by sensing a change of the state of refrigerant present in the refrigerant circuit, and a compressor deactivating circuit for deactivating the compressor in response to the determination of the refrigerant charge determining sensor. The refrigerant charge rate is appropriately suppressed by the refrigerant flow suppressing mechanism to prevent generation of an excessive amount of bubbles of refrigerant in the refrigerant circuit. Completion of a proper refrigerant charge can be precisely and easily detected by the refrigerant charge determining sensor.

Refrigerant overcharge prevention system

A refrigerator having a refrigerant circulating circuit for circulating a mixture of a refrigerant and a refrigerating machine oil. The refrigerator includes a compressor with a bypass circuit or a variable displacement compressor, a state detecting sensor for sensing the degree of separation of the refrigerant mixture, determining circuit for determining whether the detected degree of separation is in a two phase separation area, and a control unit for controlling the amount of the refrigerant passing through the bypass circuit or the displacement of the variable displacement compressor. When the refrigerant mixture enters into the two phase separation area, the amount of discharge or the displacement of the compressor is decreased. The temperature of refrigerant mixture is lowered accordingly and the phase changes from the two phase separation area. The refrigerating machine oil is maintained in a uniformly mixed state with the refrigerant and circulates with the refrigerant to the compressor. As a result, a lock up or breakage of the compressor is prevented.

Refrigerator with lubricant mixture sensor

An air conditioning system having a circuit for determining whether sufficient refrigerant is present in the system by detecting a phase state of the refrigerant. The circuit comprises a comparison circuit for comparing a detection signal of a state detecting sensor with a first reference value and a second reference value lower than the first reference value. An indication signal is output after the detection signal exceeds the first reference value until the detection signal is less than the second reference value. When the amount of refrigerant in the system is proper, even if the detection signal varies due to translucent lubricating oil in the refrigerant, the indication signal is continued to be output unless the detection signal drops below the second reference value. The amount of refrigerant in the refrigerant circuit can be accurately determined and maintained within a proper range. If the detection signal becomes less than the second reference value from, for example, leakage of refrigerant, the amount of refrigerant in the refrigerant circuit can also be accurately determined as insufficient.

Refrigerant charge detection system for an air conditioning system

In a fuel supply control system for an internal combustion engine, a voltage value to be applied to a fuel pump is controlled depending on a monitored alcohol concentration contained in a fuel to allow the fuel pump to supply a controlled amount of the fuel which is determined based on the monitored alcohol concentration contained in the fuel.

Fuel supply control system for internal combustion engine

A fail-detection system is designed for detecting failure of a fuel concentration sensor for monitoring concentration of one of a plurality of different types of fuels which are blended to be supplied to an internal combustion engine, which fuel concentration sensor varies output signal level depending upon the monitored fuel concentration in the blended fuels. The system comprises first means for receiving the output signal from the fuel concentration sensor for providing a monitored data associated with monitored fuel concentration, second means for providing a reference data representative of normal range of the value of the monitored data, and third means for comparing the monitored data with the reference data for detecting abnormality of the fuel concentration sensor when the monitored data is out of a predetermined relationship with the reference data.

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Tatebayashi, Japan

Masaru Kuribara