JPH05322352A - Air conditioner - Google Patents

Abstract

PURPOSE:To sufficiently obtain a differential pressure in order to return a four-way valve to a state of a room cooling cycle when a compressor is stopped, etc., in a remote capacitor type room cooling air conditioner in which a heating cycle can be conducted at the time when a room temperature falls. CONSTITUTION:A discharge side connector 17 of a heating operation switching four-way valve 2, a condenser side connector 20, an evaporator side connector 19 and a suction side connector 18 provided in an air conditioner are respectively connected to a discharge tube of a compressor 1, a tube for feeding refrigerant to an outdoor unit, a tube for feeding refrigerant to a heating heat exchanger 7 and a low pressure tube between an evaporator 6 and the compressor 1. The connector 18 of the valve 2 becomes a low pressure and the connector 17 becomes a high pressure even in the case of room cooling and heating to obtain sufficient differential pressure necessary to switch the valve. Accordingly, the switching valve is not stopped at an intermediate position even in the case of the room cooling and heating, but a stable refrigerating cycle can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called remote condenser type air conditioner in which an indoor unit is provided with a compressor, an evaporator, an accumulator and a decompression mechanism, and an outdoor unit is provided with only a condenser. The present invention relates to an air conditioner having an indoor unit equipped with a heating heat exchanger for raising the room temperature when the temperature is low.

[0002]

2. Description of the Related Art An air conditioner of this type is used for air conditioning in a room in which an electronic computer, a communication device or the like is installed. Since the electronic computer and the communication device generate heat during operation, the air conditioner performs cooling operation to cool it. However, when the room temperature is still low after the start of the computer or the communication device in winter etc., the cool air of the temperature lower than the temperature suitable for the operation of the computer or the communication device to be air-conditioned by the cooling operation of the air conditioner is generated. When sent to the air-conditioning target, it adversely affects the air-conditioning target.To prevent this, when the room temperature falls below a preset temperature, the air-conditioning device uses a heating heat exchanger (a kind of condensing unit). The air conditioner to raise the temperature of the air blown from the air conditioner.

A four-way valve is generally used as the refrigerant flow path switching valve for switching between the cooling operation and the heating operation, and the differential pressure between the high-pressure refrigerant and the low-pressure refrigerant is used for the switching operation of the four-way valve. Is common.

Conventionally, this type of air conditioner is disclosed in Japanese Patent Laid-Open No. 3-1.
As described in Japanese Patent No. 29269, the refrigerant outlet side high pressure pipe of the heating heat exchanger is connected to the suction side connection port of the heating operation switching four-way valve, and the refrigerant is supplied to the outdoor unit during the heating operation by switching the valve. It is supposed to be sent.

[0005]

In the above-mentioned prior art, since the suction side connection port of the four-way valve also has a high pressure, the differential pressure for returning the four-way valve to the cooling operation state when the compressor is stopped. However, there was a problem that the four-way valve stopped at the intermediate position because of insufficient security.

In view of the above problems, an object of the present invention is to provide an air conditioner of this type which can obtain a stable refrigerant cycle without the switching valve stopping at an intermediate position during both cooling operation and heating operation. There is

[0007]

In order to achieve the above object, the air conditioner of the present invention is characterized by what is stated in each of the claims.

[0008]

In the air conditioner of the present invention, the state of the refrigerant flow path switching valve becomes reliable during both the cooling operation and the heating operation, and a stable refrigeration cycle can be formed.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, second and third embodiments of the present invention will be described below with reference to FIGS. 1, 2 and 3, respectively.

First Embodiment As shown in FIG. 1, an air conditioner according to this embodiment is of a remote condenser type, and an indoor unit A has a compressor 1, an expansion valve (pressure reducing device) 5, an evaporator 6 and a heating unit. A heat exchanger 7, an accumulator 8, main components of the blocking valves 3 and 4, and a four-way valve 2 for controlling the flow direction of the refrigerant, solenoid valves 9 and 10,
The check valves 11, 12 and 13 are provided, while the outdoor unit B is composed of main components of the condenser 14 and the blocking valves 15 and 16, which are connected by pipes as shown in the figure. The compressor discharge side connection portion 17 of the four-way valve 2 is a discharge pipe of the compressor 1, and the condenser side connection portion 20 is a pipe for sending refrigerant to the outdoor unit.
The evaporator side connection part 19 is connected to a pipe for sending the refrigerant to the heating heat exchanger 7, and the compressor suction side connection part 18 is connected to a low pressure pipe between the evaporator 6 and the compressor 1.

During the cooling operation, the four-way valve 2 is in the switching state shown by the solid line, the solenoid valves 9 and 10 are both closed, and the refrigerant discharged from the compressor 1 is the four-way valve 2 and the check valve 11. After passing through the stop valve 3 and the stop valve 15, the condenser 14 of the outdoor unit
Sent to and condensed, blocking valve 16, blocking valve 4, check valve 1
3. A refrigerating cycle is constituted in which the refrigerant enters the evaporator 6 through the expansion valve 5, evaporates, and returns to the compressor 1 through the accumulator 8.

On the other hand, during the heating operation, the four-way valve 2 is switched as shown by the broken line, and the refrigerant discharged from the compressor 1 is switched in the flow direction by the four-way valve 2 to the heating heat exchanger 7. The sent refrigerant is condensed, and the condensed refrigerant is sent to the outdoor unit through the solenoid valve 10 and the check valve 12 or is sent to the outdoor unit through the solenoid valve 10 and the check valve 12 and the solenoid valve. It is controlled so as to be divided into those which are sent to the upstream side of the expansion valve 5 via 9 or to be sent to the upstream side of the expansion valve 5 via the solenoid valve 9.

To describe the flow of the refrigerant during the heating operation in more detail, the refrigerant condensed from the compressor 1 through the four-way valve 2 in the heating heat exchanger 7 is an electromagnetic valve at the initial stage when the heating operation is switched to. By closing 9 and opening the solenoid valve 10, the compressor 1 passes through the check valve 12, the outdoor heat exchanger 14, the check valve 13, the expansion valve 5, the evaporator 6 and the accumulator 8.
At the stage where a certain amount of time has passed after that, the refrigerant condensed in the heating heat exchanger 7 is cooled by the solenoid valves 9 and 10.
By opening both of them, a part of them passes through the solenoid valve 10, the check valve 12, the outdoor heat exchanger 14 and the check valve 13, and another part passes through the solenoid valve 9, both of which are expanded Expansion valve 5, evaporator 6 and accumulator 8 after merging on the upstream side of
After passing through the transient stage as described above, and after the transition to the complete heating operation after passing through the above-described transient stage, the refrigerant condensed in the heating heat exchanger 7 is transferred to the solenoid valve 10 By closing and opening the solenoid valve 9, all flow through the solenoid valve 9, the expansion valve 5, the evaporator 6 and the accumulator 8 to the path returning to the compressor 1.

The liquid refrigerant accumulated in the heating heat exchanger 7 during the heating operation is then transferred to the cooling / refrigeration cycle via the evaporator-side connection portion 19 and the suction-side connection portion 18 of the four-way valve 2 when switching to the cooling operation. It is supposed to be collected.

By configuring the refrigeration cycle as described above, in the four-way valve 2, the compressor suction side connecting portion 18 is always low pressure and the compressor discharge side connecting portion 17 is always high pressure. When the four-way valve 2 is switched by utilizing the differential pressure, the differential pressure required for switching the four-way valve 2 is sufficiently secured.

Second Embodiment As shown in FIG. 2, this embodiment is a remote condenser type air conditioner similar to the first embodiment, and the indoor unit A is
A compressor 1, an expansion valve 5, an evaporator 6, a heat exchanger 7 for heating, an accumulator 8, and main components of a blocking valve 3 and 4, and a three-way valve 21 for controlling the flow direction of the refrigerant, a solenoid valve 9,
10, 22 and check valves 11, 12, and 13 are provided. On the other hand, the outdoor unit B is composed of main components of a condenser 14, blocking valves 15 and 16, and is connected by pipes. The three connection portions of the three-way valve 21 are connected to the discharge pipe of the compressor 1, the pipe for sending the refrigerant to the outdoor unit, and the pipe for sending the refrigerant to the heating heat exchanger 7, respectively, as shown in the figure. A refrigerant recovery pipe is connected from the inlet pipe of the heating heat exchanger to a low-pressure pipe between the evaporator 6 and the accumulator 8 via the electromagnetic valve 22.

During the cooling operation, the three-way valve 21 is in the switching state shown by the solid line, the solenoid valves 9 and 10 are closed, and the solenoid valve 22.
The refrigerant discharged from the compressor 1 is opened by the three-way valve 2
1, the check valve 11, the stop valves 3 and 15 and the sent to the condenser 14 of the outdoor unit, the stop valves 16 and 4, the check valve 13,
A refrigeration cycle that enters the evaporator 6 through the expansion valve 5 and returns to the compressor 1 through the accumulator 8 constitutes a refrigeration cycle.

On the other hand, during the heating operation, the three-way valve 21
Is switched as shown by a broken line, the solenoid valve 22 is closed, the flow direction of the refrigerant discharged from the compressor 1 is switched by the three-way valve 21, and the refrigerant is sent to the heat exchanger 7 for heating and condensed. The condensed refrigerant is sent to the outdoor unit via the solenoid valve 10 and the check valve 12, or the solenoid valve 10 and the check valve 12 are connected.
To the outdoor unit through the solenoid valve 9 and the expansion valve 5
Is controlled so that it is sent to the upstream side of the expansion valve 5 or is sent to the upstream side of the expansion valve 5 via the solenoid valve 9, but the details thereof are the same as those described in the first embodiment. ..

The liquid refrigerant accumulated in the heating heat exchanger 7 during the heating operation is then returned to the low pressure pipe between the evaporator 6 and the accumulator 8 by opening the solenoid valve 22 when switching to the cooling operation. It is then collected in the cooling and refrigeration cycle.

In this embodiment, the switching operation of the three-way valve 21 is performed not by using the differential pressure of the refrigerant, but by using electromagnetic force. Therefore, the three-way valve 21 can be reliably switched regardless of the problem of eliminating the differential pressure for switching as in the above-described conventional technique.

Third Embodiment As shown in FIG. 3, this embodiment is a remote condenser type air conditioner like the first embodiment. The indoor unit A is
A compressor 1, expansion valves 5 and 23, an evaporator 6, a heat exchanger 7 for heating, an accumulator 8, blocking valves 3 and 4, and four-way valve 2 for controlling the flow direction of the refrigerant, a solenoid valve 9, 10, 24 and 25, check valves 11, 12 and 13 are provided, and the outdoor unit B includes a condenser 14 and a blocking valve 15
And 16 main parts, each connected by piping as shown in the figure.

During the cooling operation, the four-way valve 2 is in the switching state shown by the solid line, the solenoid valves 9, 10, 24 and 25 are all closed, and the refrigerant discharged from the compressor 1 is a four-way valve. 2, the check valve 11, the blocking valve 3, and the blocking valve 15 to be sent to the condenser 14 of the outdoor unit, and the blocking valve 16, the blocking valve 4, the check valve 13, and the expansion valve 5 to enter the evaporator 6, A refrigeration cycle that returns to the compressor 1 via the accumulator 8 is configured.

On the other hand, during the heating operation, the four-way valve 2 is switched as shown by the broken line, and the flow direction of the refrigerant discharged from the compressor 1 is switched by the four-way valve 2, so that the heating heat exchanger 7 is heated. The flow of the refrigerant sent to and condensed in the heating heat exchanger 7 is completely transferred to the heating operation through the transitional stage after the switching of the heating operation similar to that described in the first embodiment ( However, the solenoid valves 24 and 25 are closed until then). However, in the third embodiment, the solenoid valves 24 and 25 are opened and compressed after the completion of the heating operation. The refrigerant condensed from the machine 1 through the four-way valve 2 in the heat exchanger 7 for heating is sent to the upstream side of the expansion valve 5 through the electromagnetic valve 9, where it is branched and a part of the expansion valve 5 and the evaporator 6 are supplied. And it returns to the compressor 1 through the accumulator 8 and the other part is
The expansion valve 23, the solenoid valve 24, the blocking valve 4 and the blocking valve 16 are sent to the heat exchanger 14 of the outdoor unit to evaporate (at this time, the outdoor heat exchanger 14 acts as an evaporator), and the blocking valve 15 , The blocking valve 3, the solenoid valve 25, the outdoor heat exchanger side connection part 20 of the four-way valve 2 and the compressor suction side connection part 18, and the low pressure pipe between the evaporator 6 and the accumulator 8 to the compressor 1
Return to. Here, the evaporation capacity of the evaporator 6 is controlled by adjusting the opening degrees of the expansion valve 5 and the expansion valve 23, and the balance with the condensing capacity of the heating heat exchanger 7 is changed. Thus, a heating operation cycle capable of changing the indoor heating capacity can be obtained.

[0024]

According to the present invention, the switching valve does not stop at the intermediate position during the cooling operation and the heating operation.
A stable refrigeration cycle can be obtained.

[Brief description of drawings]

FIG. 1 is a refrigeration cycle system diagram of an air conditioner according to a first embodiment of the present invention.

FIG. 2 is a refrigeration cycle system diagram of an air conditioner of a second embodiment of the present invention.

FIG. 3 is a refrigeration cycle system diagram of an air conditioner of a third embodiment of the present invention.

[Explanation of symbols]

1 ... Compressor 2 ... Four-way valve 3, 4 ... Blocking valve 5 ... Expansion valve 6 ... Evaporator 7 ... Heating heat exchanger 8 ... Accumulator 9, 10 ... Solenoid valve 11, 12, 13 ... Check valve 14 ... Condensing 15 and 16 ... Blocking valve 17 ... Four-way valve compressor discharge side connection 18 ... Four-way valve compressor suction side connection 19 ... Four-way valve evaporator side connection 20 ... Four-way valve condenser side connection 21 ... Three-way valve 22 ... Solenoid valve 23 ... Expansion valve 24,25 ... Solenoid valve

Claims (3)

[Claims] 1. An air conditioner for constructing a cooling and refrigeration cycle by connecting an indoor unit equipped with a compressor, an evaporator and a decompression device and an outdoor unit equipped with a condenser by means of a refrigerant pipe. A heat exchanger for a heater is provided in the compressor, and a refrigerant passage switching valve for switching between cooling operation and heating operation is provided on the discharge side of the compressor, and when the refrigerant passage switching valve is switched to the heating operation, Performing a heating operation cycle in which the discharged refrigerant is sent to the heat exchanger for the heater, condensed, and returns to the compressor via the pressure reducing device and the evaporator to heat the indoor air passing through the heat exchanger for heating. In the air conditioner capable of performing the above, a four-way valve is provided as the refrigerant flow path switching valve, and the compressor discharge side connection part, the condenser side connection part, the evaporator side connection part, and the compressor suction side connection of this four-way valve. The divisions are An air conditioner connected to a discharge pipe of a compressor, a pipe for sending a refrigerant to an outdoor unit, a pipe for sending a refrigerant to a heat exchanger for heating, and a low-pressure pipe between an evaporator and a compressor. 2. An air conditioner for constructing a cooling / refrigeration cycle by connecting an indoor unit equipped with a compressor, an evaporator and a pressure reducing device and an outdoor unit equipped with a condenser with a refrigerant pipe. A heat exchanger for a heater is provided in the compressor, and a refrigerant passage switching valve for switching between cooling operation and heating operation is provided on the discharge side of the compressor, and when the refrigerant passage switching valve is switched to the heating operation, Performing a heating operation cycle in which the discharged refrigerant is sent to the heat exchanger for the heater, condensed, and returns to the compressor via the pressure reducing device and the evaporator to heat the indoor air passing through the heat exchanger for heating. In the air conditioner capable of performing the above, a three-way valve is provided as the refrigerant flow path switching valve, and the three connection parts of the three-way valve are the discharge pipe of the compressor, the pipe for sending the refrigerant to the outdoor unit, and the heating Cool to heat exchanger A pipe that is connected to a pipe that sends the medium and that has an electromagnetic valve for collecting the refrigerant from the heating heat exchanger to the refrigeration cycle during cooling operation is compressed from the inlet pipe of the heating heat exchanger to the evaporator. An air conditioner characterized by being connected to a low-pressure pipe between the machine and the machine. 3. A part of the refrigerant condensed by the heating heat exchanger during the heating operation is decompressed by a decompressor different from the decompressor and sent to a condenser provided in the outdoor unit, and the condenser is provided. 2. The air conditioner according to claim 1, wherein the air conditioner is used as an evaporator, and after being evaporated here, is returned to the compressor via the four-way valve.