JPS58127036A - Coolant circulation control device of for conditioner - Google Patents

Abstract

PURPOSE:To quicken the rise-up of cooling capacity of a compressor during an operational mode by suppressing as low as possible the temperature rise of an indoor side heat exchanger upon stopping the compressor. CONSTITUTION:By making a first electromagnetic valve 7 into a ''closed'' state upon stopping the compressor 1, a liquid coolant and a gaseous coolant of high temperature and high pressure existing within an outdoor heat exchanger 2 are sealed in a heat exchanger. That is, upon stopping the compressor 1, high and low pressure balance in the freezing cycle is checked, and the outdoor heat exchanger 2 is maintained at a high pressure, and at the same time, the liquid coolant of a high temperature passing through a pressure reducing device 4 prevented from flowing into an indoor heat exchanger 5 to thereby prevent the increase in th temperature of the indoor heat exchanger 5, which has been cooled at the time of actuating the compressor 1. Thereafter, a temperature detector 9 detects an operation starting temperature TH of the compressor 1 and immediately before starting the compressor 1, power is supplied to the coil of a second electromagnetic valve 8 provided in the high and low pressure bypass circuit by an electronic controller 10 to make the second electromagnetic valve 8 into an ''opened'' state.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a refrigerant flow control device for an air conditioner.

Conventionally, in an air conditioner having a compressor or the like, the operation of the compressor has been controlled by detecting indoor air temperature. According to this control, when the cooling capacity of the air conditioner is greater than the cooling load of the air-conditioned space, the compressor repeats ON and OFF operation near the set temperature.

In such a case, in an air conditioner equipped with a refrigeration cycle as shown in Fig. 1, the high pressure and low pressure of the refrigeration cycle try to balance when compressor a stops, so the temperature inside the outdoor heat exchanger is The high-temperature, high-pressure liquid refrigerant present in the chamber passes through the pressure reducer C and flows to the indoor heat exchanger d.

As a result, the temperature of the indoor heat exchanger d, which was being cooled when the compressor a was operating, rises, and when the compressor a starts operating again, the indoor heat exchanger d, which has a larger heat capacity, is cooled first. The disadvantage is that it takes time to cool down, and there is a considerable delay in the rise of cooling capacity. In FIG. 1, e represents an achievator, f represents an outdoor fan, q represents an indoor fan, and h represents a detection thermostat.

The present invention has been made in view of the above-mentioned drawbacks of the conventional art, and its purpose is to minimize the temperature rise of the indoor heat exchanger when the compressor is stopped, thereby increasing the cooling capacity when the compressor is in operation. The purpose is to speed up the start-up.

Hereinafter, FIGS. 2 to 2 of the accompanying drawings showing one embodiment of the present invention.
This will be explained with reference to FIG.

Without further ado, an example of a refrigerant circuit of an air conditioner will be explained with reference to FIG.

In the figure, 1 is a compressor, 2 is an outdoor heat exchanger, 3 is an outdoor fan, 4 is a pressure reducer, 5 is an indoor heat exchanger, 6 is an indoor fan, 7 and 8 are first and second These solenoid valves are connected to form a refrigeration cycle and an air conditioning circuit. 9 is a temperature detector that detects the suction temperature of the indoor heat exchanger 5.

Next, a schematic electrical circuit of such an air conditioner will be explained with reference to FIG. Here, the same parts as in FIG. 2 are given the same numbers and will be explained.

In the figure, 11 is a control power supply voltage, 12 is an operation switch, 13 is a relay for the indoor fan (motor) 6, 14 is a relay for the compressor 1 and outdoor fan (motor 3), and 10 is an electronic control device. As is well known, the electronic control device 10 not only controls the operation of the compressor 1, the indoor fan 6, and the outdoor fan 3 based on the temperature detected by the temperature sensor 9, but also controls the operation of the first and second fans according to the above control. It also has a function of controlling energization to the coil of the solenoid valve 78.

The operation of the above configuration will be explained with reference to FIGS. 4 and 5.

In FIG. 4, time is plotted on the horizontal axis. The indoor temperature is plotted on the vertical axis.

The operating state of the compressor 1 and the opening/closing states of the first and second electromagnetic valves 7 and 8 are shown. Figure 6 shows a typical pattern in which the compressor repeats ON and OFF operation, with time on the horizontal axis and cooling capacity and temperature of the indoor heat exchanger on the vertical axis. This is what is shown. Note that the solid line indicates the case of this embodiment, and the dashed line indicates the case of the conventional example.

When trying to cool an air-conditioned room, first turn on operation switch 1.
2, the indoor air temperature Ta detected by the temperature detector 9 is higher than the set temperature, so the electronic control device 1
0, the relays 13 and 14 are respectively closed, the compressor 1, the outdoor fan 3, and the indoor fan 6 are started, and at the same time, the coil of the first solenoid valve 7 is energized, and the first
The solenoid valve is "open".

As a result, the high-temperature, high-pressure gas discharged from the compressor 1 is condensed and liquefied in the outdoor heat exchanger 2, and is reduced in pressure in the pressure reducer 4 to become a low-temperature, low-pressure refrigerant, which passes through the indoor heat exchanger 6 to the compressor 1.
Return to At this time, heat exchange is performed with the surrounding indoor air in the indoor heat exchanger 5, and the cool air is blown out by the indoor fan 6. As time passes, the indoor air temperature Ta gradually decreases, and when it reaches the stop temperature TL, the temperature detector 9 detects this, and the relays 13, 14 open, and the compressor 1. The outdoor fan 3 and the indoor fan 6 are stopped. At the same time, the energization of the coil of the first electromagnetic valve 7 is stopped, resulting in a "closed" state.

Thereafter, the above state is maintained until the temperature detected by the temperature detector 9 reaches the operation start temperature T of the compressor 1.

In this way, by closing the first solenoid valve 7 when the compressor 1 is stopped, the high temperature and high pressure liquid refrigerant and gas refrigerant present in the outdoor heat exchanger 2 are transferred into the heat exchanger. Lock up. In other words, when the compressor 1 is stopped, the high-low pressure balance in the refrigeration cycle is prevented, the outdoor heat exchanger 2 is kept at high pressure, and the high-temperature liquid refrigerant is passed from the outdoor heat exchanger 2 through the pressure reducer 4 to the room. This prevents the air from flowing into the inner heat exchanger 6 and increasing the temperature of the indoor heat exchanger 5, which has been cooled during the operation of the compressor 1. Thereafter, the temperature detector e detects the operation start temperature TH of the compressor 1, and immediately before starting the compressor 1, the electronic control device 1o energizes the coil of the second solenoid valve 8 provided in the high-low pressure bypass circuit. Then, the second solenoid valve 8 is brought into the "open" state. In order to reduce the starting torque of the block compressor 1, the pressures on the discharge side and suction side of the compressor 1 are balanced.

Immediately after starting the compressor 1, the coil of the first solenoid valve 7 is energized to be in the "open" state, and at the same time, the coil of the second solenoid valve 8 is de-energized to be in the "closed" state.

Hereinafter, similar operations will be repeated.

By equipping the electronic control device 1o with such a control function, the indoor heat exchanger 5 can be controlled when the compressor 1 is stopped.
As a result, the heat capacity of the indoor heat exchanger 5 at the time of starting the compressor 1 is reduced, and the start-up of the cooling capacity is much faster than that of the conventional compressor 1.

Note that a two-way valve that operates by sensing pressure may be used instead of the first and second electromagnetic valves 8 as long as it brings out the functions and effects of the present invention.

As is clear from the above embodiments, the refrigerant flow control device for an air conditioner according to the present invention includes a compressor, an indoor heat exchanger,
Between the outdoor heat exchanger and the indoor heat exchanger of the refrigeration cycle which are composed of the outdoor heat exchanger and the pressure reducer, and between the bypass circuit connecting the compressor discharge side and the suction side, the first, A second on-off valve is provided, and a temperature controller is further provided to detect indoor temperature and control the operation of the compressor, and the opening and closing of the first on-off valve is synchronized with the operation of the compressor. The second on-off valve is set to the open state only during operation, and the second on-off valve is set to the "open" state only during the period from just before starting the compressor until the time of starting the compressor.
The temperature rise in the indoor heat exchanger is suppressed by forcibly maintaining the pressure balance when the compressor is stopped, so the temperature rise in the indoor heat exchanger is By reducing the heat capacity, it is possible to start up the cooling capacity extremely quickly, and because the cooling capacity starts up quickly, the operating time of the compressor when trying to cool the air-conditioned space is shortened. Overall, this reduces annual power consumption, improves energy efficiency, and increases the amount of dehumidification when the compressor is in operation, improving comfort.

[Brief explanation of drawings]

Fig. 1 is a refrigerant circuit diagram of a conventional air conditioner, Fig. 2 is a refrigerant circuit diagram of an air conditioner equipped with a refrigerant flow control device according to an embodiment of the present invention, and Fig. 3 is a refrigerant circuit diagram of the same air conditioner. 4 is an explanatory diagram showing the operation control status of the air conditioner, and FIG. 6 is a diagram showing the ON/OFF state of the air conditioner.
FIG. 2 is an explanatory diagram showing temporal changes in cooling capacity and indoor heat exchanger temperature during operation. 1...Compressor, 2...Outdoor heat exchanger, 3
...Outdoor fan, 4 ...Pressure reducer, 6...
・Indoor heat exchanger, 6... Indoor fan, 7...
...First solenoid valve, 8...Second solenoid valve, 9...
...Temperature detector. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
figure

Claims (1)

[Claims] Connects between the outdoor heat exchanger and the indoor heat exchanger, and between the compressor discharge side and the suction side of the refrigeration cycle, which consists of a compressor, indoor heat exchanger, outdoor heat exchanger, and pressure reducer. First and second on-off valves are provided between the bypass circuits, respectively,
Furthermore, a temperature regulator is provided to detect the indoor temperature and control the operation of the compressor, and further to control the opening and closing of the first on-off valve.
An air conditioner in which the second on-off valve is kept open only from immediately before the start of the compressor to when the compressor is started, in synchronization with the operation of the compressor. refrigerant flow control device.