Abstract: A heat exchanger includes a rotary compressor having two compression pumps and a motor for driving the compressor pumps, a condenser connected to the rotary compressor, a regulator connected to the condenser and with an evaporator connected to the regulator. An electric power is supplied from an inverter circuit to the motor of the rotary compressor. The output frequency of the inverter circuit is controlled by a frequency controlling device according to a heat load of a heat exchange circuit subjected. The rotary compressor is operated according to a parallel operation pattern in which the two compression pumps are actuated or a single operation pattern in which a single compression pump is actuated. Either one of the two operation patterns is selected by a selecting device according to the operational condition of the heat exchanger. The switching between the single operation and the parallel operation is performed by a switching device according to the output signal of the selecting device.

Abstract: A rotary compressor includes first and second compressor sections, and a motor for driving the compressor sections. The first and second compressor sections have first and second cylinders, respectively, and each cylinders has a suction port. First and second suction pipes are connected to the suction ports, and first and second change over valves are provided at the first and second pipes, respectively. The first cylinder has a release port for releasing a port of the gas being compressed in the first cylinder. A release pipe provided with a third changed over valve is connected to the release port. The operaations of the first to third valves are controlled by a control circuit so that the capacity of the compressor varies in the plurality of steps in accordance with the loads applied thereto.

Abstract: A rotary compressor includes first and second compressing devices in a casing to successively carry out a parallel operation wherein first and second compressing devices are parallely driven and a single operation wherein one of first and second compressing devices is driven. A relatively high driving frequency is applied to the rotary compressor during single operation as compared to the driving frequency during parallel operation necessary to produce the same compressing capacity to enhance the EER of the rotary compressor and to extend the variable compressing capacity of the rotary compressor.

Abstract: A humidity-measuring device used with an air conditioner provided with an interior heat exchanger and refrigerant pipe which comprises:a first sensor which is provided at an inlet of the interior heat exchanger and produces a first output signal denoting a temperature of air streams drawn into the interior heat exchanger;a heat conductor positioned in a state extending to the inlet at one end of that portion of the refrigerant pipe, through which the refrigerant flows with a low pressure;a second sensor which is disposed in that portion of the heat conductor which faces the inlet and produces a second output signal; anda system controller which is provided with a memory for storing data on the air humidity corresponding to the first and second output signals, and measures the humidity of the sucked air from the data stored in the memory in accordance with the first and second output signals from the first and second sensors.

Abstract: An air conditioner comprises a device body having first and second air channels, an evaporator disposed in the first air channel for cooling the air passing therethrough, a first drain tray disposed below the evaporator for receiving dew drops formed on the evaporator and falling therefrom and thus for containing the drain, and a second drain tray disposed below the first drain tray for receiving dew drops formed on the first drain tray and falling therefrom and the drain overflowing the first drain tray. The second air channel is defined between the first and second drain trays.