JPS6236042Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a heating and cooling device that has both a cooling cycle and a heating cycle.

This type of air conditioning system described above usually has a cooling cycle configured as a closed circuit consisting of a compressor, an outdoor heat exchanger (condenser for cooling), a capillary tube, and an indoor heat exchanger (evaporator for cooling), and a compressor, It also has a heating cycle in which a refrigerant heater and an indoor heat exchanger are configured as a closed circuit, and performs cooling operation or heating operation by switching between the cooling cycle and the heating cycle. The compressor and indoor heat exchanger are common components of the cooling cycle and the heating cycle, and switching between the cooling cycle and the heating cycle can be performed by opening and closing a solenoid valve installed on the discharge side of the compressor. It is. The solenoid valves include one that controls the conduction of refrigerant to the outdoor heat exchanger and another that controls the conduction of the refrigerant to the indoor heat exchanger or refrigerant heater. As a result, one of the cooling cycle or the heating cycle is established and the other is placed in a dormant state. Since these electromagnetic valves cannot handle a small flow rate, normally closed types that are closed in a non-excited state are used. However, when the power to the outdoor unit, which is made up of an outdoor heat exchanger, etc., is cut off, both of the solenoid valves are closed, and the discharge port of the compressor and these solenoid valves are closed. During this period, the refrigerant gas is locked at a high pressure, which impairs the pressure balance between the suction side and the discharge side of the compressor, making it difficult to restart the compressor.

The present invention aims to solve the above-mentioned problems of an air-conditioning system equipped with a refrigerant circuit having a normally closed electromagnetic valve that cuts off refrigerant conduction on the discharge side of a compressor.

Next, the configuration of the present invention will be specifically explained based on an embodiment shown in the drawings.

The air conditioning system shown in the drawing as an application example of the present invention has a pipe connected to the discharge port of the compressor 1 that branches into two systems, forming a cooling cycle and a heating cycle. One switching solenoid valve 2, which is closed in the non-energized state, is provided near the branch for each system. When focusing on the movement of refrigerant, each solenoid valve 2 controls the conduction of refrigerant to each cycle at the most upstream portion of the cooling cycle and heating cycle, and is the main body for switching between cooling and heating operations. The downstream configuration of each solenoid valve 2 is a cooling cycle or a heating cycle, and the application of the present invention is not restricted by the downstream configuration of each solenoid valve 2. That is, in the present invention, the above-mentioned solenoid valve 2 is provided in the refrigerant circuit communicating with the discharge port of the compressor 1, and the operation of the solenoid valve 2 causes a gap between the discharge port of the compressor 1 and the solenoid valve 2. This applies to devices that have a structure in which the refrigerant gas can be sealed. In other words, a portion immediately before the suction port of the compressor 1 and a portion immediately after the discharge port are connected through the pressure balance circuit 3 that straddles the compressor 1. Pressure balance circuit 3
It is sufficient to allow a slight flow of refrigerant, and is normally closed by an inserted solenoid valve 4 for small flow. This solenoid valve 4 is a normally open type that is closed when energized and opened when not energized, and is energized during cooling or heating operation. The above-mentioned solenoid valves 2, which determine whether the refrigerant from the compressor 1 is introduced into the cooling cycle or the heating cycle, are operated in both directions unless power is cut off to the outdoor unit, which is a unit such as the outdoor heat exchanger 5. are not closed together. However, if the power to the outdoor unit is cut off, both electromagnetic valves 2 will eventually close regardless of whether the outdoor unit is in heating operation or cooling operation. At this time, the solenoid valve 4 of the pressure balance circuit 3 is also de-energized because it is connected to the same power supply system as these solenoid valves 2, but this solenoid valve 4 is opened and the pressure balance circuit 3 is made conductive. That is, the refrigerant gas locked in a high pressure state on the discharge side of the compressor 1 is released by conducting the pressure balance circuit 3, and restarting the compressor 1 becomes easy. In order to prevent the refrigerant gas from locking up, it would be best to make each solenoid valve 2 for switching between cooling and heating operation a normally open type, but these solenoid valves 2 have a large flow rate, Currently, it is difficult to employ a closed type solenoid valve, and it cannot be easily applied.

In the figure, reference numeral 6 indicates an indoor heat exchanger, 7 indicates a capillary reach tube, 8 indicates a refrigerant heater, and 9 indicates a check valve. The flow of refrigerant during cooling operation is as shown by the solid line arrow in the figure, through compressor 1 → solenoid valve 2 → outdoor heat exchanger 5 → check valve 9 → capillary reach tube 7 → indoor heat exchanger 6 → Return to compressor 1. Further, the flow of refrigerant during heating operation is as shown by the dotted line arrow in the figure, from the compressor 1 → solenoid valve 2 → indoor heat exchanger 6 → check valve 9 → refrigerant heater 8 and returns to the compressor 1. However, regarding the configuration of the cooling cycle and the configuration of the heating cycle, in the illustrated example, the refrigerant heater 8 is arranged in parallel with the indoor heat exchanger 6, but it is a well-known circuit configuration that is very commonly adopted. Even if there is, it will not impede the application of the present invention.

As is clear from the above description of the embodiments, the air conditioning system of the present invention includes a compressor, an indoor heat exchanger,
A cooling cycle consisting of a series circuit of a capillary reach tube and an outdoor heat exchanger is combined with a heating cycle consisting of a series circuit of the compressor, indoor heat exchanger, and refrigerant heater. The cooling cycle and heating cycle are switched by switching the solenoid valve installed upstream of the heat exchanger and the solenoid valve installed upstream of the indoor heat exchanger of the above heating cycle, and the outdoor heat exchanger is built in. The air conditioning system is configured such that both of the solenoid valves are closed when the power supply to the outdoor unit is stopped, and the solenoid valve is configured to open the suction side and the discharge side of the compressor without excitation. Since the refrigerant gas is connected by the pressure balance circuit included in the refrigerant, even if the solenoid valve for switching between air conditioning and heating is closed, the refrigerant gas will not be locked in a high pressure state on the discharge side of the compressor. The pressure on the suction side and the discharge side can be easily adjusted without complicating the circuit, and the compressor can be restarted easily.

[Brief explanation of the drawing]

The figure is a refrigerant system diagram showing a heating and cooling device as an application example of the present invention. 1... Compressor, 2... Solenoid valve, 3... Pressure balance circuit, 4... Solenoid valve, 5... Outdoor heat exchanger.

Claims (1)

[Scope of utility model registration request] A cooling cycle consists of a series circuit of a compressor, an indoor heat exchanger, a capillary reach tube, and an outdoor heat exchanger, and a heating cycle consists of a series circuit of the compressor, indoor heat exchanger, and refrigerant heater. The cooling cycle and the heating cycle are switched by opening and closing the solenoid valve installed upstream of the outdoor heat exchanger of the cooling cycle and the solenoid valve installed upstream of the indoor heat exchanger of the heating cycle. This is an air-conditioning system in which both of the solenoid valves are closed when power to an outdoor unit with a built-in outdoor heat exchanger is turned off, and the above-mentioned solenoid valves are closed immediately before the suction port and the discharge port of the compressor. An air-conditioning and heating system characterized in that the part immediately after the part is connected to the part immediately after the part by a pressure balance circuit including a solenoid valve that opens when de-energized.