Kabushiki Kaisha Toshiba

Nobuo Kawai

Masao Isshiki

Masao Ozu

Eiji Kuwahara

Atsushi Nagasawa

Atsuyuki Hiruma

Kazuhiko Akiyama

Takao Hoshi

Kazuaki Kamiyama

Yoshiaki Nagaoka

Tohru Kubo

Satoshi Miwa

A refrigeration cycle has a compressor, an outdoor rotary-type heat exchanger, a motor-operated expansion valve, and an indoor rotary-type heat exchanger which are sequentially connected to each other to circulate a refrigerant. A tank is set in a connected state or a non-connected state with respect to a refrigerant discharge side of the compressor. A detector detects at least a pressure at one side of each of the exchangers. A first controller sets the tank in a non-connected state when a normal operation of an air conditioner is to be started, and controls the capacity of the compressor, the rotational speed of the exchangers, and the opening degree of the valve in accordance with an air-conditioning load, thereby performing the normal operation of the air conditioner. A second controller causes the compressor to keep operating at a predetermined capacity until a detection pressure from the detector coincides with a preset value, when the air conditioner is to be stopped, and sets the tank in a connected state while controlling the valve to a predetermined opening degree, thereby recovering a refrigerant in the tank. A third controller rotates the exchangers at a predetermined speed when the air conditioner is to be started, and sets the tank in a connected state while controlling the valve to a predetermined opening degree, thereby filling the refrigerant in the exchangers from the tank.

Air conditioner using rotary-type heat exchangers

In a heat pump heating apparatus of this invention, a compressor included in a refrigerating cycle is operated at a speed corresponding to a blowoff temperature so that the temperature of air blown off into a room through an indoor fan from a condenser becomes close to a set value when a room temperature is less than its set value. The indoor fan is operated depending upon a room temperature, i.e., is operated under the state of a relatively great airflow when the room temperature is far lower than its set value and is operated under the state of a relatively small airflow when the room temperature is closer to its set value.

Heat pump heating apparatus

A heat-pump type refrigeration cycle includes at least a compressor capable of switching between cooling and heating modes. A first memory stores first reference temperature data for the cooling mode, and second reference temperature data for the heating mode. A second memory stores first set data for setting a cooling temperature and second set data for setting a heating temperature. A mode selector compares room temperature detection data with the first and second reference temperature data, in accordance with an automatic operation instruction, and outputs a first signal for selecting the cooling mode or a second signal for selecting the heating mode. A controller sets the heat-pump type refrigeration cycle in the cooling or heating mode, in accordance with the first or second signal, and controls the compressor in a drive state or a stop state, so that a comparison difference between the first or second set data and the room temperature detection data becomes zero. A monitor is connected to monitor the stop state of the compressor, and, when the stop state continues for a predetermined period of time or longer, to provide a re-selection instruction equivalent to the automatic operaiton instruction to the mode selector.

Air conditioner with automatic selection and re-selection function for

An air conditioning apparatus includes a variable frequency power source device for providing an AC electric power with a variable frequency, a variable capacity compressor driven by the AC electric ipower and a starting detector for detecting a starting state of the compressor a predetermined time after the compressor is energized. When the starting detector detects the starting failure of the compressor, the variable frequency power source device feeds the compressor with a starting frequency voltage until the starting detector detects changes in the level of the input current to the compressor within a predetermined time to heat refrigerant in the compressor, and then feeds the compressor with a driving frequency voltage corresponding to the required air conditioning load. When no change in the level of the input current is detected within the predetermined time, the variable frequency power source device supplys the compressor with the driving frequency voltage immediately after the predetermined time elapsed.

Air conditioning apparatus and control method thereof

Growing community of inventors

Fujinomiya, Japan

Nobuo Kawai