Mitsubishi Denki Kabushiki Kaisha

Masami Imanishi

Hiroaki Hama

Takeshi Yoshida

Hideaki Tagashira

Naoki Tanaka

Osamu Morimoto

Hiroshi Nakata

Moriya Miyamoto

Yasufumi Hatamura

Hitoshi Kido

Keiji Nonami

Yasuyuki Funahashi

Katsumi Kasano

Shunsuke Ohara

Yoshimichi Nakagawa

Seiichi Kato

A heat storage type air conditioner which is free from a difficulty that, when a general cooling and heating circuit and a cold radiating and heat radiating circuit are operated separately or simultaneously, the quantities of refrigerant in those circuits become smaller or larger than required, so that its compressor is damaged or the cooling or heating capacity is lowered. When, in a heat storage type air conditioner, first and second bypass circuits 22 and 23 are closed, a general cooling and heating circuit 18 driven by a compressor 1 and a cold radiating and heat radiating circuit 21 driven by a refrigerant gas pump 13 are made independent of each other, so that a cooling operation or a heating operation is carried out with the aid of a first use-side heat exchanger 4a and a second use-side heat exchanger 4b. Therefore, in the air conditioner, the refrigerant or refrigerating machine oil will never concentrate in any one of the two circuits. In a cold storing operation or a heat storing operation for a heat storage tank 8, the two bypass circuits 22 and 23 are opened, so that the general cooling and heating circuit 18 is communicated with the cold radiating and heat radiating circuit 21. As a result, the refrigerant is led from the general cooling and heating circuit into the heat storage tank 8 to store cold or heat in the heat storing medium 7 therein.

Heat storage type air conditioner, and defrosting method

A heat storage type air conditioning system capable of performing refrigerant receiving and discharging control and oil quantity control, which, in operating the general cooling circuit and the cold radiating circuit simultaneously or separately, is free from difficulties that the compressor is damaged or the cooling capacity is lowered when the quantities of refrigerant in those circuits are excessively increased or decreased, and is able to continue the operations with the quantity of refrigerant and the quantity of ice machine oil adjusted to suitable values. In the heat storage type air conditioning system, evaporators are provided in a general cooling circuit driven by a compressor and in a cold radiating circuit driven by a refrigerant gas pump, respectively, so that those circuits operate independently of each other. Furthermore, bypass circuits are provided to allow refrigerant to flow between liquid pipes and between gas pipes in those circuits. In a cold storing operation, the bypass circuits are closed, so that a cold storing circuit is formed by the compressor, a condenser, a first pressure reducing mechanism, and a cold storing heat exchanger.

Heat storage type air conditioning apparatus

An air conditioning system including a refrigerant circuit having a compressor, a three port switching valve, a four port reversing valve, an outdoor heat exchanger, a first throttle device including a first decompression device, a second throttle device including a first decompression device, an indoor heat exchanger and an accumulator connected in series by use of refrigerant pipes; a first bypass circuit which is constructed to carry out heat exchange with the intake pipe connecting between the accumulator and the compressor, and which is connected as a bypass to the pipe connecting between the first and second throttle devices; a second bypass circuit having a check valve to bypass the first decompression device; a third bypass circuit having a check valve to bypass the second decompression device; a fourth bypass circuit which is connected as a bypass to the pipe between the first and second throttle devices, and which is smaller than the discharge pipe in inside diameter; and a fifth bypass circuit which is connected as a bypass to the pipe between the first and second throttle devices through a pressure regulating valve; wherein the three port switching valve is switched to open the fourth bypass circuit, thereby carrying out defrosting.

Heating and cooling air conditioning system with improved defrosting

A heat pump employing a capillary tube as an expansion device is disclosed. The main throttle portion of the heat pump comprises a main capillary tube and a by-pass through which a portion of the refrigerant flows and cools the refrigerant flowing through the main capillary tube. A solenoid valve for controlling the flow of refrigerant through the main capillary tube is connected to the intake of the main capillary tube, and an electrical expansion valve is connected to the intake of the by-pass for controlling the flow therethrough. An auxiliary capillary tube for cooling and an auxiliary capillary tube for heating are connected in parallel with the main throttle portion, both capillary tubes having a higher resistance to flow than the main capillary tube. The auxiliary capillary tubes increase the range over which control of the flow of refrigerant can be achieved, allowing both a smaller flow of refrigerant during under minimum cooling or heating load as well as a larger flow of refrigerant under maximum cooling or heating load.

Heat pump with capillary tube-type expansion device

A heat pump system in which the amount of opening of an expansion valve is set to an optimum value in dependence upon the inlet temperature of water undergoing heat exchange at a utilization side heat exchanger and an inlet temperature of air undergoing heat exchange at a non-utilization side heat exchanger. In response to the sensed temperature values, a controller determines the optimum amount of valve opening so as to provide a maximum system capacity and efficiency. The controller may be implemented with a microprocessor and a read-only memory. In the read-only memory are stored data values representing optimum opening settings of the expansion valve corresponding to various values of the sensed inlet temperature of water at the utilization side heat exchanger and the inlet temperature of the air at the non-utilization side heat exchanger.

Heat pump system

Described is a cooling/heating and hot water service system making use of a single heat source apparatus. The system includes a heat pump chiller designed to perform cyclic operations of heating and cooling, a heat exchanger unit having a heat exchanger adapted for supplying hot water and a water reservoir. The operating time zone for storage of hot water and the operating time zone for heating and cooling the room are set by a first program timer while the operating time zone for servicing hot water is set by a second program timer. In this manner, the cooperating time zone of the system is divided into the operating time zone for storage of hot water and the operating time zone for heating and cooling, and the operation of storage of hot water is effected during the time of the day that heating or cooling of the room is unnecessary while servicing of hot water is effected during the time of operation of heating or cooling the room, with resultant improvement in the operating rate of the unit and more efficient heating/cooling and servicing of hot water.

Growing community of inventors

Wakayama, Japan

Masami Imanishi