Mitsubishi Denki Kabushiki Kaisha

Fumio Matsuoka

Hitoshi Iijima

Kisuke Yamazaki

Kiyoshi Sakuma

Tomofumi Tezuka

Yasuo Nakashima

Mitsuo Umehara

Tomohiko Kasai

Takashi Nakamura

Yasuo Sato

Shigeo Takata

Hidenori Ishioka

Akio Fukushima

Hidekazu Tani

Hiroyuki Umemura

Yoshihiro Tanabe

Kazuaki Isono

Yoshiaki Tanimura

Tetsuya Mochizuki

Toshizo Nishizawa

Hajime Kitauchi

Keiko Okuma

Hiroshi Kasagi

Toshiaki Yamaguchi

Takeshi Sugimoto

Junji Tamari

Tetsuya Yamashita

Kouichi Negoro

Yasuo Shibuya

Mutsumi Nakamura

Ken Tomita

Jiro Okajima

The invention concerns a reversible rotary compressor which can compress refrigerant in either of the forward and reverse directions, without providing a valve mechanism in a closed container. In a reversible rotary compressor including a cylinder, a rolling piston, and a slide vane, two inlet/outlet ports are formed in a space between the outer surface of the rolling piston and the inner surface of the cylinder in a state that the two inlet/outlet ports are disposed on both sides of the slide vane. The two inlet/outlet ports are closed by the rolling piston when the rolling piston is positioned at the top dead center and fully opened when the rolling piston is positioned at the bottom dead center. Two refrigerant pipes, coupled with the inlet/outlet ports, are provided in the side wall of the cylinder. The two refrigerant pipes are closed by the rolling piston when the rolling piston when the rolling piston is positioned at the top dead center and fully opened when the rolling piston is positioned at the bottom dead center.

Reversible rotary compressor and reversible refrigerating cycle

A condenser (2), an electronic expansion valve (5), an evaporator (6), and a motorized suction throttle valve (8) are connected in series with a compressor. When a capacity is increased, the electronic expansion valve (5) is controlled to be in a throttling direction and the motorized suction throttle valve (8) is controlled to be in an unthrottling direction in association with the control of the electronic expansion valve (5), and when a capacity is decreased, the electronic expansion valve (5) is controlled to be in an unthrottling direction and the motorized suction throttle valve (8) is controlled to be in a throttling direction in association with the control of the electronic expansion valve (5). While a capacity control of a compressor by a throttle control is been carried out, such associated control is made between the electronic expansion valve (5) and the motorized suction throttle valve (8), realizing a fine temperature control in a refrigerating machine without hunting.

Refrigeration cycle system

An air conditioning system for multiple rooms, comprising:

Air conditioning system

A cooling and heating concurrent operation type of multiple refrigeration cycle comprises an indoor unit including a variable delivery type of compressor and an outdoor heat exchanger; indoor units including indoor heat exchangers, respectively; triple connection pipes of a high pressure gas pipe, a high pressure liquid pipe and a low pressure gas pipe, the triple connection pipes connecting between the outdoor unit and the indoor units; pressure detection means for detecting the intake pressure of the compressor and the discharge pressure of the compressor; and calculation and control means for comparing two detected values of the intake pressure and the discharge pressure of the compressor with two set values of a set intake pressure and a set discharge pressure, and for making variable controls of the compression capability of the compressor and the heat exchange capability of the outdoor heat exchanger based on the respective deviation values between the respective detected values and the respective set values, which are obtained as the results of the comparison.

Cooling and heating concurrent operation type of multiple refrigeration

A frequency control apparatus of a multi-refrigeration cycle is provided with a current sensor to detect a primary current for a motor or a pressure sensor to detect a pressure at the discharge side of a compressor to detect a load in the refrigeration cycle. When a value detected by the sensor is estimated as being lower than a predetermined value range, the frequency of a current to be supplied to the motor is increased, and when the value detect by the sensor is estimated as being higher than the predetermined value range, the frequency is decreased, whereby the rising time of the refrigeration cycle can be shortened. Further, the frequency is determined by a weighted error average value of the difference between target room temperature in the rooms and detected temperature in the rooms to thereby control the multi-refrigeration cycle to provide an appropriate performance.

Frequency control apparatus of a multi-refrigeration cycle system

A multiroom air conditioner has a plurality of indoor heat exchangers connected to a single outdoor heat exchanger. A reversible expansion valve is installed on a liquid-side branch pipe for each of the indoor heat exchangers, and a solenoid valve is installed on a gas-side branch pipe for each indoor heat exchanger. Temperature sensors are provided on the liquid-side branch pipes, on the gas-side branch pipes, and on the outlet side during cooling of the outdoor heat exchanger. A pressure sensor or a temperature sensor detects the saturation temperature on the high-pressure side of the compressor. Based on the saturation temperature on the high-pressure side of the compressor, the temperature on the outlet side during cooling of the outdoor heat exchanger, and the temperatures in the liquidside branch pipes, a controller controls the expansion valves so as to obtain a target degree of subcooling during cooling and heating. The controller can also control the expansion valves so that the temperatures in each of the branch pipes are approximately equal to one another.

Multiroom air conditioner

An air conditioning apparatus comprises a refrigerant circuit in which a compressor, a four-way valve, a room side heat exchanger, a pressure-reducing device and an outdoor side heat exchanger are connected in this order, wherein there is provided with a refrigerant temperature detector provided at a pipe line near the outdoor side heat exchanger, a room temperature detector for detecting temperature of a room and a controlling device which is electrically connected to the refrigerant temperature detector and the room temperature detector, said controlling device controlling operations for room-warming and defrosting based on inputs from the detectors.

Air conditioning apparatus

A control device for refrigeration cycle constructed with a compressor, a condenser, an electrically operated expansion valve, an evaporator, and so forth, all being connected in series, wherein there are further provided a by-pass extending from an inlet or an outlet or both of the expansion valve upto an inlet of the compressor through a capillary tube; a first temperature sensor to sense a temperature of a cooling medium at the inlet of the compressor; a second temperature sensor to sense a temperature of the cooling medium within an intake tubing, through which the cooling medium is taken into the inlet of the compressor; and a control device which calculates a super-heat quantity of the cooling medium taken into the compressor on the basis of a difference between the detection outputs of the first and second temperature sensors, and controls a degree of opening of the electrically operated expansion valve, thereby enabling the refrigeration cycle to be operated at high efficiency and in an energy-saving mode.

Control device for refrigeration cycle

The cooling performance of an air conditioning apparatus is controlled by a selective combination of three methods of regulation, in accordance with the required degree of cooling. A first stage of regulation controls the volume of air delivered by a fan 6, a second stage controls the amount of refrigerant flowing through a pressure reduction means 7, and a third stage controls the amount of refrigerant circulating in a compressor feedback circuit 9. Any one of or combination of these three controls may be employed in accordance with the prevailing temperature condition and the required cooling performance.

Air conditioning apparatus with temperature regulated cooling

Growing community of inventors

Kamakura, Japan

Fumio Matsuoka