JPH0395359A - Air conditioner - Google Patents

Abstract

PURPOSE:To continue operation without a significant rise in the temperature of delivery gas refrigerant by opening a solenoid valve by the first signal output from a bypass open-close judging device when it is judged that the detected temperature of refrigerant delivered from a compressor is higher than the first preset temperature. CONSTITUTION:In cooling operation, when the temperature Td detected by a delivery temperature detector 13 becomes higher than the first set temperature T1 and a solenoid valve 7 is opened, a portion of liquid refrigerant is depressurized by a flow regulator 8 after liquefied by heat-exchanging at an outdoor side heat exchanger 3a, exchanges heat with the room side air at an auxiliary outdoor side heat exchanger 6, flows into a pipe 10 together with the refrigerant that evaporates at a room side heat exchanger 5a, and is sucked into a compressor 1 through a four-way valve 2. In heating operation, a portion of high temperature and high pressure refrigerant delivered from the compressor 1 through the four-way valve 2 flows into the outdoor side heat exchanger 6 and the liquefied refrigerant is depressurized by the flow regulator 8, flows into a pipe 11 together with the refrigerant that is condensed at the room side heat exchanger 5a and depressurized by an expansion device 4, and flows into the outdoor side heat exchanger 3a, so that the temperature of gas refrigerant delivered from the compressor 1 falls.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention is directed to an air conditioner that suppresses an excessive rise in temperature of refrigerant discharged from a compressor and expands the operating range.

[Conventional technology]

A conventional device of this type is shown in FIG. In the figure, (1) is the compressor, {2) is the four-way valve, and (3a)
is an outdoor heat exchanger equipped with a blower fi (3b), (4)
is an expansion mechanism, and (5a) is an indoor heat exchanger equipped with a blower (5b).

In the figure, solid arrows indicate the flow direction of refrigerant during cooling operation, and broken arrows indicate the flow direction of refrigerant during heating operation.

Next, we will explain the operation of the compressor (1) during cooling operation.
) The high-temperature, high-pressure gas refrigerant discharged from the four-way valve +2> flows into the outdoor heat exchanger (3a), where it is connected to the blower (
3b) It liquefies by exchanging heat with the outdoor air sent from 3b). The liquefied liquid refrigerant is depressurized by the expansion mechanism (4) and flows back to the indoor heat exchanger (5a), where it exchanges heat with indoor air sent from the blower (5b) and is vaporized again.

The vaporized gas refrigerant passes through the four-way valve (2) to the compressor (1).
I get sucked into it. A refrigeration cycle is thus formed.

Next, the operation during heating operation will be explained. Compressor (1)
The high-temperature, high-pressure gas refrigerant discharged from the four-way valve (2) flows into the indoor heat exchanger (5a), where the blower (5a)
b) It liquefies by exchanging heat with the indoor air that is sent. The liquefied liquid refrigerant is depressurized by the expansion mechanism (4) and flows into the outdoor heat exchanger (3a), where it exchanges heat with outdoor air sent from the blower (3b) and is vaporized again. The vaporized gas refrigerant passes through the four-way valve (2) and is sucked into the compressor (1).

In this way, the refrigeration cycle becomes 5L! 2.

[Problem to be solved by the invention]

In conventional air conditioners such as those mentioned above, when the indoor air temperature is high during cooling operation, and the outdoor air temperature is high during heating operation, and the degree of superheating of the gas refrigerant sucked into the compressor is high, the compression When the ratio of the discharge pressure to the suction pressure of the compressor, that is, the compression ratio, is large, the air temperature outside the room during cooling operation is high, the air temperature inside the room during heating operation is high, and the discharge pressure of the compressor is high. There was a problem in that the temperature of the refrigerant discharged from the compressor rose significantly, reducing the reliability of the compressor.

This invention was made to solve the above-mentioned problems, and an object of the present invention is to obtain an air conditioner that can continue operating without a significant rise in the temperature of the refrigerant gas discharged from the compressor.

[Means to solve the problem]

The present invention includes a refrigerant circuit in which a compressor, a four-way valve, an outdoor heat exchanger, an expansion mechanism, and an indoor heat exchanger are connected via piping, and a pipe connecting the four-way valve and the indoor heat exchanger. a bypass path that branches midway and communicates with the pipe connecting the outdoor heat exchanger and the expansion mechanism; an outdoor auxiliary heat exchanger provided midway through the bypass path; and an outdoor auxiliary heat exchanger provided midway through the bypass path. a solenoid valve connected in series with the outdoor auxiliary heat exchanger; a discharge temperature detection means installed in a pipe connecting the compressor and the four-way valve to detect the discharge refrigerant temperature; A first valve that opens the electromagnetic valve when the detected temperature of the discharge temperature detection means is compared with a preset first set temperature and the detected temperature is determined to be higher than the first set temperature. By providing a bypass passage opening/closing determination means for outputting a signal and a solenoid valve control means for opening the solenoid valve when the determination means outputs the first signal, the air conditioner b is constructed. This is to achieve the above objective.

[Effect]

In the air conditioner according to the present invention, the temperature of the refrigerant discharged from the compressor is detected by the discharge temperature detection means, and when the detected temperature is determined to be higher than the first preset temperature, the bypass path is opened or closed. The first signal output from the determining means opens the PT magnetic valve to develop a bypass path equipped with an outdoor auxiliary heat exchanger. As an example, if the air conditioner is completely shut down, Figure 1 shows (1) to (5b).
) is exactly the same as the conventional example shown in Figure 3, so its explanation will be omitted.
The line M is the connection between the four-way valve {2) and the indoor heat exchanger (A), and 'lυ is the connection between the outdoor heat exchanger (3a) and the expansion pA thin (
4), (1a is the bypass path that connects the pipe and the pipe (1υ), (6) is the bypass path (1'!:
It is an outdoor auxiliary heat exchanger provided in the middle of J, and is provided adjacent to the outdoor heat exchanger (3a). (A) is a bypass path (located in the middle of 17J) and an outdoor auxiliary heat exchanger (
6) is a solenoid valve connected in series to the piping αυ side, and (8) is a flow rate adjustment device located in the middle of the pipe bus path and connected between the outdoor heat exchanger (6) and the piping qυ. . l1 is a discharge temperature detection means provided in the pipe connecting the compressor (1) and the four-way valve (2), (14l is a discharge temperature detection means (
The detected temperature h of 13l is set in advance as the first set temperature T.
If it is determined to be higher than L, a first signal is output, and the detected temperature 1u of the discharge temperature detection means U is compared with a second set temperature T2 which is lower by D than the first set temperature Tl, and determined to be lower. bypass path opening/closing determination means that outputs a second signal when the
(151 is a solenoid valve control means that opens the solenoid valve (γ) when the bypass path opening/closing determination means (14l outputs the first signal) and closes the solenoid valve (A) when the second signal is output.

FIG. 2 is a flowchart showing the operation of the solenoid valve (γ). In the step, the discharge temperature detection means (13l detected temperature Td and first set temperature T1 are compared, 1u≧T1
If so, proceed to step t, open the t solenoid valve (γ), proceed to step (24J, and if Td<Tl, open the solenoid valve (7).
) to keep the valve closed. Next, in step t241, the detected temperature of the discharge temperature detection means ('l3) is compared with the second set temperature T2, which is set to a value lower than the first set temperature TI, and if Tli<Tz, the step Proceed to step ■ to close the solenoid valve (7), and if 'Ili≧T2, then close the solenoid valve (7).
) to keep the valve open.Next, we will explain the operation of the refrigerant applied to the bypass path. During cooling operation, the discharge gas refrigerant temperature of the compressor (1) rises, and the detected 7M degrees 1u of the discharge temperature detection means (13) becomes higher than the first set temperature T1, and the solenoid valve (A) closes. When the valve is opened, a part of the liquid refrigerant that has been liquefied through heat exchange in the outdoor heat exchanger (3a) is reduced in pressure by the flow rate regulator (8) and is exchanged with the outdoor air in the outdoor auxiliary heat exchanger (6). Heat exchange and piping (
In step 10), it joins with the refrigerant that has evaporated in the indoor heat exchanger (5a), passes through the four-way valve (2), and is sucked into the compressor (1). In other words, the evaporator becomes relatively larger than the condenser in the refrigeration cycle, and the high pressure can be lowered without increasing the degree of superheating of the suction gas refrigerant in the compressor (1). 1) The discharge gas refrigerant temperature decreases. Also, during heating operation, the compressor (1
) the discharge gas refrigerant temperature rises, and the discharge temperature detection means (1
When the detected temperature of 3L becomes higher than the first set temperature T1 and the tIiff valve (γ) opens, a portion of the high temperature and high pressure gas refrigerant is discharged from the compressor (1) and passes through the four-way valve (2). Flows into the outdoor heat exchanger (6), where it exchanges heat with the outdoor air and liquefies.

The liquefied liquid refrigerant is depressurized by the flow rate adjustment device (8), passed through the pipe qυ, condensed in the indoor heat exchanger (air), and merges with the depressurized refrigerant in the expansion mechanism (4) for outdoor heat exchange. vessel(
3a). In other words, in the refrigeration cycle, the condenser is relatively large compared to the evaporator, and the compressor (1)
Since the high pressure can be lowered without increasing the degree of superheating of the suction gas refrigerant of the compressor (1), the temperature of the discharge gas refrigerant of the compressor (1) is reduced. A refrigerant garden path to which a four-way valve, an outdoor heat exchanger, an expansion mechanism, and an indoor heat exchanger are connected via piping, and a pipe connecting the four-way valve and the indoor heat exchanger branches to the outdoor side. a bypass passage communicating with the piping connecting the heat exchanger and the expansion mechanism; an outdoor auxiliary heat exchanger provided in the middle of the bypass passage; and an outdoor auxiliary heat exchanger located in the middle of the bypass passage. A solenoid valve connected in series with the exchanger, a discharge temperature detection means installed in the pipe connecting the compressor and the four-way valve, and a discharge temperature detection means for detecting the discharge refrigerant temperature, and a temperature detected by the discharge temperature detection means. and a preset first set temperature, and when it is determined that the detected temperature is higher than the first set temperature, a bypass path that outputs a first signal to open the solenoid valve. Since the air conditioner is configured by providing an opening/closing determination means and a solenoid valve control means for opening the solenoid valve when the determination means outputs the first signal, the intake gas of the compressor is The high pressure can be lowered without increasing the degree of superheating of the refrigerant, and the discharge gas refrigerant temperature is also lowered, improving the reliability of the compressor and expanding the operable range of the air conditioner according to the present invention. be able to.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram of an air conditioner according to an embodiment of the present invention, and FIG. 2 is a flowchart showing the operation of a solenoid valve.
FIG. 3 is a refrigerant circuit diagram of a conventional air conditioner. In the figure, (1) is a compressor, (2) is a four-way valve, (2A
) is the outdoor heat exchanger, (4) is the expansion mechanism, (5a) is the indoor heat exchanger, (6) is the outdoor auxiliary heat exchanger, (7) is the solenoid valve, Sumino is the bypass path, G The normal is the discharge temperature detection means,
[141 is a bypass passage opening/closing determination means, (one is a tFa valve control means. In each figure, the same reference numeral indicates 41 or a corresponding part.

Claims (1)

[Claims] A refrigerant circuit in which a compressor, a four-way valve, an outdoor heat exchanger, an expansion mechanism, and an indoor heat exchanger are connected via piping, a refrigerant circuit branching from the middle of the piping connecting the four-way valve and the indoor heat exchanger, and a refrigerant circuit connecting the four-way valve and the indoor heat exchanger to the outdoor side. a bypass passage communicating in the middle of piping connecting the heat exchanger and the expansion mechanism; an outdoor auxiliary heat exchanger provided in the middle of the bypass passage; and an outdoor auxiliary heat exchanger located in the middle of the bypass passage. a solenoid valve connected in series with the
A discharge temperature detection means is provided in a pipe connecting the compressor and the four-way valve and detects the discharge refrigerant temperature, and the temperature detected by the discharge temperature detection means is compared with a first preset temperature, bypass passage opening/closing determining means for outputting a first signal for opening the solenoid valve when the temperature is determined to be higher than a first set temperature;
1. An air conditioner comprising a solenoid valve control means for opening the solenoid valve when the signal is output.