JP2743710B2 - Air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner capable of performing a cooling / heating operation and a dehumidifying operation.

[0002]

2. Description of the Related Art Conventionally, as this type of air conditioner, for example, the one shown in FIG. 2 is known. This air conditioner includes a compressor 31, a four-way switching valve 32, an indoor heat exchanger 3
3. Expansion valve 34 and outdoor heat exchanger 3 as pressure reducing device
5 are sequentially connected by conduits 36a to 36f. The indoor heat exchanger 33 is divided into first and second heat exchangers 33a and 33b so as to enable a dehumidifying operation, and a capillary tube 38 (see FIG. 3) is provided between the two heat exchangers 33a and 33b. A dry pressure reducing mechanism 37 in which on-off valves 39 are connected in parallel to each other is provided, and a bypass pipe 40 provided with an electromagnetic valve 41 provides a pipe 36a on the discharge port side of the compressor 31 and the expansion valve 3.
4 and the pipeline 36c between the second indoor heat exchanger 33b. As shown in FIG. 3, the on-off valve 39 is provided in the valve chamber 4.
2 and a valve element 43 slidably fitted in the valve element 2. The valve element 43 is urged toward a valve seat 44, and contracts when a low-temperature refrigerant flows (see FIG. 3A). The spring comprises a shape memory spring 45 which extends when flows through (see FIG. 3 (C)), and a bias spring 46 which urges the valve body 43 in the reverse direction.

In the above air conditioner, in order to perform the cooling operation, the refrigerant discharged from the compressor 31 is circulated as indicated by the solid line arrow in FIG. Evaporate at 33. At this time,
A low-temperature refrigerant flows into the on-off valve 39 between the second indoor heat exchangers 33a and 33b as shown by an arrow L in FIG.
Is separated from the valve seat 44, and the on-off valve 39 is opened. Therefore, both indoor heat exchangers 33a and 33b both work as evaporators to cool the room. Conversely, to perform the heating operation,
By switching the four-way switching valve 32, the discharged refrigerant is circulated as indicated by the dashed arrow in FIG. Then, the on-off valve 39 is provided as shown in FIG.
The high-temperature refrigerant flows in as indicated by the arrow H in FIG.
5 extends, but due to the pressure difference between the upper and downstream sides of the valve body 43 and the difference between the spring forces of the springs 45 and 46, the valve body 43
4, the on-off valve 39 is opened. Therefore, both indoor heat exchangers 33a and 33b work as condensers to heat the room, and outdoor heat exchangers 35 work as evaporators.

On the other hand, in the dehumidifying operation, the expansion valve 34 is closed, the solenoid valve 41 is opened, and the high-temperature refrigerant gas from the compressor 31 is passed through the bypass line 40 to the second refrigerant line as indicated by the one-dot chain line arrow in FIG. The pressure is directly sent to the indoor heat exchanger 33b. Then
A high-temperature refrigerant flows into the on-off valve 39 as indicated by an arrow H in FIG. 3C, and the valve body 43 is seated on the valve seat 44 due to the extension of the shape memory spring 45 and the pressure difference between the upstream and downstream sides of the valve body. And on-off valve 3
9 closes. As a result, the refrigerant flows into the capillary tube 38 and expands and decompresses therein, so that the upstream second indoor heat exchanger 33b serves as a condenser and the downstream first heat exchanger 33b serves as a condenser.
The indoor heat exchangers 33a each work as an evaporator. And
The indoor air circulated by an indoor fan (not shown)
First, it is cooled and dehumidified through the first heat exchanger 33a,
Next, it is heated to about room temperature through the second heat exchanger 33b to become dehumidified air.

[0005]

However, in the conventional air conditioner, the expansion valve 34 is fully closed during the dehumidifying operation, but the outdoor heat exchanger 35 is discharged from the compressor 31 via the four-way switching valve 32. Since the refrigerant gas is connected to the outlet, the discharged refrigerant gas also flows into the outdoor heat exchanger 35, and when the outside air temperature is low or when the outdoor is rainy or rainy, the flowing refrigerant condenses and accumulates in the outdoor heat exchanger 35. Would. Therefore, bypass line 4
There is a shortcoming that the amount of refrigerant supplied to the indoor heat exchanger 33 through 0 is insufficient, and the dehumidification circuit is in a state of lack of gas, so that stable dehumidification operation cannot be performed. Therefore, an object of the present invention is to provide an air conditioner capable of performing a stable dehumidifying operation by devising a circuit so that refrigerant does not accumulate in an outdoor heat exchanger during a dehumidifying operation.

[0006]

Means for Solving the Problems In order to achieve the above object, an air conditioner of the present invention, as exemplified in FIG.
Compressor 31, first four-way switching valve 32, first indoor heat exchanger 33
a, the second indoor heat exchanger 33b, the pressure reducing device 34, and the outdoor heat exchanger 35 are sequentially connected by pipes 36a to 36f.
A check valve 2 is interposed between the second indoor heat exchangers 33a and 33b with a pressure reducing means 38 and an on-off valve 39 connected in parallel with each other, and one end 1a of the check valve 2 on the flow direction side is connected. A bypass pipe 1 connected to the pipe 36c between the pressure reducing device 34 and the second indoor heat exchanger 33b, and one end 3a between the first four-way switching valve 32 and the suction port 31b of the compressor 31. Capillary tube 3 connected to the above-mentioned conduit 36f
And the discharge port 31a of the compressor 31 and the first four-way switching valve 3
2, the discharge line 31a communicates with the first four-way switching valve 32, and the bypass line 1
And the other end 1b of the capillary tube 3 communicates with the other end 3b of the capillary tube 3, or the discharge port 31a communicates with the other end 1b of the bypass pipe 1, and the first four-way switching valve 3
A second four-way switching valve 4 is provided, which is switched to communicate the second end 2b of the capillary tube 3 with the second end 3b.

[0007]

In the case of the cooling / heating operation, the second four-way switching valve 4 is connected to the discharge port 31a of the compressor 31 and the first four-way switching valve 32,
And the other end 1b of the bypass pipe 1 and the capillary tube 3
The other end 3b of the first heat exchanger 33a and the open / close valve 39 between the first and second indoor heat exchangers 33a and 33b. When the first four-way switching valve 32 is switched, the refrigerant gas discharged from the compressor 31 via the second four-way switching valve 4 is supplied to the outdoor heat exchanger 35 or the indoor heat exchanger 3.
The air is supplied to the heat exchanger 3 and circulated, and both the indoor heat exchangers 33a and 33b are operated as condensers for heating or as evaporators for cooling. At this time, one end 1a of the bypass pipe 1 is connected to a relatively high pressure pipe 36c between the pressure reducing device 34 and the second indoor heat exchanger 33b, and the other end 1b is
Since it communicates with the pipe 36f on the suction side of the relatively low-pressure compressor 31 via the second four-way switching valve 4 and the capillary tube 3, the check valve 2 provided in the bypass pipe 1 , The back pressure is always applied and the refrigerant does not flow through the bypass pipe 1.

Next, in the case of the dehumidifying operation, the second four-way switching valve 4
Is switched to a switching position in which the discharge port 31a of the compressor 31 communicates with the other end 1b of the bypass pipe 1 and the first four-way switching valve 32 communicates with the other end 3b of the capillary tube 3. The switching valve 32 is set to the same switching position as in the cooling operation, and the on-off valve 39 between the pressure reducing device 34 and the first and second indoor heat exchangers 33a and 33b is maintained in a closed state. Then, the refrigerant gas discharged from the compressor 31 is directly supplied from the second four-way switching valve 4 to the second indoor heat exchanger 33b via the check valve 2 of the bypass pipe 1 to which the forward pressure is applied, where the refrigerant gas is discharged. After being condensed, it expands through the pressure reducing means 38 connected in parallel with the on-off valve 39, enters the first indoor heat exchanger 33a, evaporates, and further passes through the first four-way switching valve 32 to the compressor 31. It returns to the suction port 31b. Therefore, the indoor air is
After being cooled and dehumidified in the indoor heat exchanger 33a, it is heated to about room temperature and dehumidified in the second indoor heat exchanger 33b. Here, one end of the outdoor heat exchanger 35 is closed by the pressure reducing device 34, while the other end is compressed at a relatively low pressure through the first four-way switching valve 32, the second four-way switching valve 4 and the capillary tube 3. It communicates with the pipeline 36f on the suction side of the machine 31. Therefore,
The refrigerant remaining in the outdoor heat exchanger 35 is sucked into the compressor 31 via this passage and collected, and therefore, even when the outside air temperature is low or the outdoor is rainy, the refrigerant remains in the outdoor heat exchanger 3.
There is no accumulation in 5. Therefore, a sufficient amount of refrigerant is supplied to the indoor heat exchanger 33 via the bypass pipe 1, and a stable dehumidifying operation can be always performed. The dehumidification capacity is controlled by adjusting the number of rotations of the compressor and the degree of throttling of the pressure reducing means.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the illustrated embodiments. FIG. 1 is a refrigerant circuit diagram showing an example of the air conditioner of the present invention. This air conditioner is provided with a second pipe 36a on the discharge port 31a side of the compressor 31 of the refrigerant circuit described in FIG.
The four-way switching valve 4 is interposed, and the second four-way switching valve 4 and the pipe 3
2c is connected by a bypass line 1 provided with a check valve 2 in place of the bypass line 40 in FIG. 2, and the second four-way switching valve 4 and a line 36f on the suction port 31b side of the compressor 31 are connected. Are connected by a capillary tube 3. Other points are shown in FIG.
This is the same as the refrigerant circuit described above, and the same members are denoted by the same reference numerals and description thereof will be omitted.

The bypass line 1 has one end 1a corresponding to the flow direction of the check valve 2 at a line 36c between the expansion valve 34 as a pressure reducing device and the second indoor heat exchanger 33b, and the other end 1b at the other end 1b. Each is connected to the second four-way switching valve 4. On the other hand, one end 3a of the capillary tube 3 has a pipe 36f on the suction port side.
The other end 3b is connected to the second four-way switching valve 4, respectively. The second four-way switching valve 4 controls the compressor 3 during the cooling / heating operation.
1 is connected to the first discharge port 31a and the first four-way switching valve 32 and is connected to the other end 1b of the bypass pipe 1 and the other end 3b of the capillary tube 3 as shown in FIG. The position is switched to a position where the outlet 3a communicates with the other end 1b of the bypass pipe 1 and the first four-way switching valve 32 communicates with the other end 3b of the capillary tube 3.

The air conditioner having the above configuration operates as follows. In the case of the cooling / heating operation, the second four-way switching valve 4 is connected to the discharge port 31a and the first four-way switching valve 32, and the other ends 1b and 3b of both the bypass pipe 1 and the capillary tube 3 are connected. Switch position. Then, when the first four-way switching valve 32 is set to the switching position shown in the figure, the high-temperature gas refrigerant discharged from the compressor 31 is sent to the outdoor heat exchanger 35 as shown by the solid arrow in the figure and condensed there. After the heat is radiated to the outside of the room, the pressure is reduced through the expansion valve 34, becomes a low-temperature liquid refrigerant, evaporates in the second indoor heat exchanger 33b, and reaches the on-off valve 39 (see FIG. 3) of the dry-time pressure reducing mechanism 37. On-off valve 39
As shown in FIG. 3A, the shape memory spring 45 is contracted by the inflowing low-temperature refrigerant and becomes fully open, so that the first and second indoor heat exchangers 33a and 33b both work as evaporators, and It is cooled down. The evaporated refrigerant is sucked into the compressor 31 via the pipes 36b and 36f, compressed again and circulated.

On the other hand, when the first four-way switching valve 32 is set to the reverse switching position, the high-temperature gas refrigerant discharged from the compressor 31 is sent to the first indoor heat exchanger 33a as indicated by a broken arrow in the figure. While being condensed here, it reaches the on-off valve 39 of the dry-time pressure reducing mechanism 37 while being mixed with a high-temperature liquid. On-off valve 39
As shown in FIG. 3 (B), the shape memory spring 45 expands due to the high-temperature refrigerant flowing therein.
Since the state is fully opened due to the difference in spring force at 46, both indoor heat exchangers 33a and 33b both work as condensers to heat the room. The control of the cooling / heating operation capacity is performed by the compressor 3
This is performed by increasing or decreasing the number of rotations of 1 or the degree of opening of the expansion valve 34. The check valve 2 of the bypass line 1 is connected to the expansion valve 34.
Is higher than the other end 1b communicating with the suction port 31b via the capillary tube 3 at all times, and a reverse pressure is constantly applied, so that the refrigerant does not flow through the bypass conduit 1.

Next, in the case of the dehumidifying operation, the first four-way switching valve 3
2 is set to the same illustrated switching position as during the cooling operation,
The second four-way switching valve 4 is connected to the discharge port 31 a and the other end 1 b of the bypass pipe 1, and the first four-way switching valve 32 is connected to the other end 3 b of the capillary tube 3. And the expansion valve 34 is fully closed. Then, the high-temperature gas refrigerant discharged from the compressor 31 is directly supplied to the second indoor heat exchanger 33b through the check valve 2 of the bypass pipe 1, which becomes a normal pressure, as indicated by the dashed line arrow in the drawing. Supplied,
Here, it condenses and reaches the on-off valve 39 of the decompression mechanism 37 at the time of dry. As shown in FIG. 3C, the on-off valve 39 is fully closed due to the expansion of the shape memory spring 45 due to the high-temperature liquid-mixed refrigerant flowing therein and the pressure difference between the upstream and downstream. as a result,
All of the refrigerant flows into the capillary tube 38 and expands and decompresses there. Therefore, the second indoor heat exchanger 33b on the upstream side as a condenser and the first heat exchanger 33a on the downstream side as an evaporator. Work each. Accordingly, the indoor air circulated by the indoor fan (not shown) is first cooled and dehumidified through the first indoor heat exchanger 33a, and then heated to about room temperature through the second indoor heat exchanger 33b and dehumidified. It becomes air.

Here, in the outdoor heat exchanger 35, a pipe 36d at one end is closed by a fully-closed expansion valve 34, and a pipe 36e at the other end.
Is connected to a relatively low-pressure pipe 36f on the suction port 31b side of the compressor via the first four-way switching valve 32, the second four-way switching valve 4, and the capillary tube 3. Therefore, the refrigerant remaining in the outdoor heat exchanger 35 passes through this passage and passes through the compressor 31.
Therefore, even if the outside air temperature is low or the outside is rainy or rainy, the refrigerant does not accumulate in the outdoor heat exchanger 35 unlike the conventional case. Therefore, at the time of the dehumidification operation, a sufficient amount of refrigerant is supplied to the indoor heat exchanger 33 via the bypass pipe 1, and a stable dehumidification operation can be always performed. The control of the dehumidifying capacity is performed by increasing or decreasing the rotation speed of the compressor 31.

In the above embodiment, since the opening / closing valve 39 having the shape memory spring 45 and automatically opening / closing according to the refrigerant temperature is used, the size and weight can be reduced. There is no merit, so there is no need to worry about fire due to electric leakage. In the above embodiment, the first and second
The pressure reducing means connected in parallel between the indoor heat exchangers is constituted by the capillary tube 38, and the open / close valve is constituted by the automatic open / close valve 39. You can also

[0016]

As is apparent from the above description, the air conditioner of the present invention comprises a compressor, a first four-way switching valve, a first indoor heat exchanger, a second indoor heat exchanger, a pressure reducing device, and an outdoor Heat exchangers are sequentially connected by a pipeline, and a pressure reducing means and an on-off valve are connected in parallel between the first and second indoor heat exchangers. One end of the capillary tube is connected to the pipeline between the pressure reducing device and the second indoor heat exchanger, and one end of the capillary tube is connected to the pipeline between the first four-way switching valve and the suction port of the compressor. A second four-way switching valve is provided in the pipe between the discharge port of the compressor and the first four-way switching valve, and the second four-way switching valve is switched to switch the discharge port and the first four-way switching valve. The other ends of both the switching valve and the bypass line and the capillary tube are connected to each other, or the discharge port and the bypass line are connected. Since the end and the first four-way switching valve and the other end of the capillary tube are communicated with each other, even when the outdoor is in a low temperature or rainy weather during the dehumidifying operation, the residual refrigerant in the outdoor heat exchanger is eliminated, and An appropriate amount of refrigerant can be supplied to the indoor heat exchanger, and a stable dehumidification operation can always be performed.

[Brief description of the drawings]

FIG. 1 is a refrigerant circuit diagram showing one embodiment of an air conditioner of the present invention.

FIG. 2 is a refrigerant circuit diagram showing a conventional air conditioner.

FIG. 3 is a detailed view showing an operation state of the dry pressure reducing mechanism of FIG. 2;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Bypass line, 2 ... Check valve, 3 ... Capillary tube, 4 ... Second four-way switching valve, 31 ... Compressor, 31a ... Discharge port, 31b ... Suction port, 32 ... First four-way switching valve, 33 indoor heat exchanger, 33a first indoor heat exchanger, 33b second indoor heat exchanger, 34 expansion valve, 35 outdoor heat exchanger, 36
a to 36f: pipeline, 37: decompression mechanism at dry time, 38: capillary tube, 39: open / close valve, 45: shape memory spring.

Claims (1)

(57) [Claims] 1. A compressor (31), a first four-way switching valve (32), a first indoor heat exchanger (33a), a second indoor heat exchanger (33b), a pressure reducing device (34), and an outdoor heat exchange. Vessels (35) are sequentially connected to pipes (36a-
36f) and the first and second indoor heat exchangers (33a, 3
In an air conditioner in which a pressure reducing means (38) and an on-off valve (39) are connected in parallel between 3b), a check valve (2) is interposed, and the check valve (2) is arranged on the flow direction side. One end (1a) is connected to the pressure reducing device (34) and the second indoor heat exchanger (3).
A bypass line connected to said line (36c) during 3b)
(1) One end (3a) is connected to the first four-way switching valve (32) and the compressor (31).
A capillary tube (3) connected to the pipe (36f) between the suction ports (31b) of the compressor, a discharge port (31a) of the compressor (31), and a first four-way switching valve (3).
2) between the discharge port (3).
1a) and the first four-way switching valve (32), and the other end (1b) of the bypass pipe (1) and the capillary tube (3).
Or the other end (3b) of the discharge port (3
1a) and the other end (1b) of the bypass line (1), and the first four-way switching valve (32) and the capillary tube
An air conditioner comprising a second four-way switching valve (4) that switches so as to communicate with the other end (3b) of (3).