JP2869257B2 - Separable 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 of a separated type in which an outdoor unit and an indoor unit are installed at remote places.

[0002]

2. Description of the Related Art There has been proposed a separate type air conditioner in which an outdoor unit and an outdoor unit are installed at a distance from each other, which is proposed by the present applicant as Japanese Patent Application No. 4-107709. As shown in FIG. 4, the air conditioner includes a main pressure reducing element 15 connected in series to the outdoor heat exchanger 7, and a heating pressure reducing element connected between the main pressure reducing element and the indoor heat exchanger 13. 16
A check valve 18 connected in parallel to the heating depressurizing element and allowing the refrigerant to flow during the cooling operation, and a length of the inter-unit pipe connected in parallel to the heating depressurizing element 16 that is equal to or more than a predetermined value and opened during the heating operation. The on-off valve 17 constitutes the decompression device 9.

[0003]

In the air conditioner proposed by the present applicant, when starting the heating operation in which the on-off valve 17 is open, there is almost no pressure difference between the pipes 60a and 60b, and the compressor does not operate. When the pressure in the pipe 60a becomes lower than the pressure in the pipe 60b due to the pulsation, the refrigerant flows through the check valve 18 and the valve body in the check valve 18 vibrates to generate noise (a so-called chattering phenomenon occurs). There was a drawback.

[0004] The present invention provides a separation type air conditioner in which chattering of a check valve is prevented when starting a heating operation in which an on-off valve is opened.

[0005]

SUMMARY OF THE INVENTION The present invention provides a compressor, a four-way valve, an outdoor heat exchanger, a main pressure reducing element, a heating pressure reducing element through which a refrigerant flows during a heating operation, and a reverse valve which is closed during a heating operation and opened during a cooling operation. A parallel circuit consisting of a stop valve , and
The piping on the suction side of the compressor
Such as accumulators that store excess refrigerant due to differences in
An outdoor unit link is connected, in that constitute the heat pump connects the indoor unit indoor heat exchanger is incorporated in unit pipes, a bypass pipe with the parallel circuit refrigerant is bypassed, the Check valve
Apply a pressure difference between the inlet and outlet of the check valve to prevent chattering.
The bypass pipe is constituted by a pipeline with an on-off valve that is opened during a heating operation with a long pipe connection.
It is a thing.

[0006]

In this separation type air conditioner, the on-off valve and the auxiliary pressure reducing element are provided in the bypass pipe bypassing the parallel circuit. Therefore, when the open / close valve is opened when the heating operation is started, the auxiliary pressure reducing element is used. Since the pressure on the upstream side of the bypass pipe is kept higher than the pressure on the downstream side of the bypass pipe, the pressure on the upstream side of the parallel circuit is kept higher than the pressure on the downstream side.

[0007]

An embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a separation type air conditioner composed of an outdoor unit 2 and an indoor unit 4 connected to the outdoor unit by an inter-unit pipe 3. The outdoor unit 2 mainly includes a compressor. 5, a four-way valve 6 for switching between cooling and heating operations, an outdoor heat exchanger 7, a receiver tank 8, a pressure reducing device 9, two accumulators 10 and 11, and a control device 12 for controlling an opening / closing valve of the pressure reducing device. With
The indoor unit 4 mainly includes an indoor heat exchanger 13 and a control device 14 for controlling an operation during a cooling operation or a heating operation. The refrigerant circuit of the air conditioner 1 is filled with the amount of refrigerant corresponding to the case where the interunit piping 3 has a maximum length of 25 m. An outdoor fan and an indoor fan for flowing air to the outdoor heat exchanger 7 and the indoor heat exchanger 13 are not shown.

The decompression device 9 is connected in parallel with the main decompression element 15, an auxiliary decompression element 16 connected in series with this element and through which the refrigerant flows during the heating operation of the standard piping, and is closed during the cooling operation and opened during the heating operation. A parallel circuit 40 constituted by the valve 18, an on-off valve 17 provided in a bypass pipe 41 that bypasses the check valve and the heating decompression element 16, an auxiliary decompression element 42 connected in series with the on-off valve, It is composed of The auxiliary pressure reducing element is composed of a one-fifth pipe smaller than the two-minute bypass pipe 41, and the pressure difference between the upstream side and the downstream side of the auxiliary pressure reducing element is 0.01 to 0.05 kg / kg.
cm ³ , and the auxiliary pressure reducing element 42
Has smaller resistance than any of the elements 15 and 16.

Reference numeral 19 denotes a setting switch arranged in the outdoor unit 2, and the inter-unit piping 3 has a predetermined size [for example, 15
m], and the setting is switched between standard piping in which the unit-to-unit piping is within a predetermined dimension (in the case where the unit-to-unit piping is within 15 m), and setting of the standard piping in which the unit-to-unit piping is within 15 m or more. . And this switch 1
9 is switched according to the installation size of the inter-unit pipe 3 at the time of installation work of the outdoor unit 2, for example, at the time of connection of the inter-unit pipe 3 or connection of the wiring 20.

The setting switch 19 is provided on a terminal plate 21 to which a wiring 20 is connected, and a terminal cover 22 is provided.
Is set, the setting switch 19 cannot be operated (see FIG. 2).

The setting switch 19 is set so that the inter-unit pipe 3 is in a long pipe state, and the control device 12 opens the on-off valve 17 during the heating operation. In other cases, the control device 12 opens the on-off valve 17. Leave closed.

Reference numeral 23 denotes a branch pipe for connecting the outdoor heat exchanger 7, the pressure reducing device 9 and the receiver tank 8, reference numeral 24 denotes a branch pipe for connecting to the service valve 25, and reference numeral 26 denotes a hot gas bypass pipe 27. Pipe 28 is an opening / closing valve provided in the hot gas bypass pipe 27, and is opened by the control device 12 during the defrosting operation.

A refrigerant pipe 29 connects the outdoor heat exchanger 7 and the distribution pipe 26, a refrigerant pipe 30 connects the distribution pipe 26 and the distribution pipe 23, and a refrigerant pipe 31 connects the outdoor heat exchanger 7 and the distribution pipe 24. The refrigerant pipe 32 to be connected is connected to the branch pipe 24 and the service valve 2.
5 is a refrigerant pipe connecting the diverter pipe 23 and the receiver tank 8, 33 is a refrigerant pipe connecting the diverter pipe 23 and the diverter pipe 24, 35 is a refrigerant pipe connecting the diverter pipe 23 and the pressure reducing device 9. Are connected to the refrigerant pipe.

Reference numeral 36 denotes a setting switch provided in the indoor unit 4 for setting a cooling operation and a heating operation.

FIG. 3 is a cross-sectional view of the check valve 18, and FIG.
Is a nylon valve element, which has a metal weight 18b
This valve body is set to a specific gravity of about 1.15 to 1.20, which is slightly heavier than the specific gravity 1.1 of the refrigerant liquid. For this reason, as shown in the figure, even when the check valve 18 is arranged in the vertical direction and the refrigerant liquid reaches the check valve from above and below, the valve element 18a does not float in the refrigerant liquid. It has become. 18c is a valve seat, and 18d is a stopper.

In such a separation type air conditioner 1, since the indoor unit 4 and the outdoor unit 2 are installed at different places, the interunit piping 3 may be long or short depending on the installation place. It may be necessary.

First, the case where the interunit piping 3 is a standard piping of 15 m or less will be described. In this case, the setting switch 19 of the outdoor unit 2 is set to “standard piping” at the time of installation work. For this reason, the control device 12 keeps the on-off valve 17 closed in both the cooling operation and the heating operation. During the cooling operation, the refrigerant from the outdoor heat exchanger 7 passes through the main pressure reducing element 15 and the check valve 18, so that
This refrigerant is decompressed only by the main decompression element 15. Also, during the heating operation, the refrigerant from the indoor heat exchanger 13 passes through the heating decompression element 16 and the main decompression element 15, so that the refrigerant is decompressed by the heating decompression element 16 and the main decompression element 15. Become.

In the case of the standard piping, the refrigerant is filled so as to be able to cope with the long piping. Therefore, although the refrigerant is somewhat surplus, the surplus refrigerant is stored in the receiver tank 8 and the accumulators 10 and 11. Since the refrigerant is accumulated, it is prevented as much as possible that the refrigerant accumulates in the heat exchangers 7 and 13. The surplus refrigerant is mainly stored in the receiver tank 8 during the cooling operation, and is mainly stored in the two accumulators 10 and 11 during the heating operation. Since the receiver tank 8 is connected to the refrigerant circuit between the outdoor heat exchanger 7 and the pressure reducing device 9 by a single refrigerant pipe 33, during cooling operation, excess liquid refrigerant is discharged from the tank 8 by the pressure in the refrigerant circuit. Gradually accumulates from below. For this reason, compared with the conventional refrigerant circuit, which has two refrigerant pipes, an inlet pipe and an outlet pipe, in the middle of the refrigerant circuit, the sound when the refrigerant is flushed resonates in the tank and causes noise. However, since the flash does not flash in the tank 8, noise is suppressed as much as possible. In addition, since the lower portion of the tank 8 is connected to the refrigerant circuit by the refrigerant pipe 33, the return of the refrigerant into the refrigerant circuit is performed quickly.

Next, the case where the unit pipe 3 is a long pipe exceeding 15 m [predetermined value] and up to 25 m will be described. In this case, the setting switch 19 of the outdoor unit 2 is set to “long piping” at the time of installation work. When the setting switch 19 is set to the long pipe, the control device 12 opens the on-off valve 17 when the heating operation is started. Then, during the cooling operation, the refrigerant from the outdoor heat exchanger 7 passes through the main decompression element 15 and the check valve 18, so that the refrigerant is decompressed only by the main decompression element 15. In the heating operation, the controller 12 opens the on-off valve 17, so that the refrigerant from the indoor heat exchanger 13 passes through the on-off valve 17, the auxiliary pressure reducing element 42, and the main pressure reducing element 15. The pressure is reduced by the pressure reducing element 42 and the main pressure reducing element 15.

At the time of this long piping and at the time of starting the heating operation, the pressure difference between the pipe 41a and the pipe 41b of the bypass pipe 41 is determined by the provision of the auxiliary pressure reducing element 42.
It is maintained at about 0.01 to 0.05 kg / cm ² . For this reason, since this pressure is applied in the direction in which the check valve 18 is closed, the possibility that the check valve 18 causes a chattering phenomenon is prevented. Further, since the resistance of the resistor 42 is very small, it can be considered that the resistance hardly increases as compared with that shown in the prior art.

Further, at the time of this start, although the auxiliary pressure reducing element 42 is provided, the pressure difference between the refrigerant in the pipes 41a and 41b is still small. For this reason, the refrigerant liquid flows through the pipes 41a,
When the check valve 18 reaches the check valve 18 from 41b, the valve body is formed of nylon, and the valve body floats up in the refrigerant liquid, so that the chattering phenomenon may occur due to the pulsation of the compressor 5, Since the valve element 18a of the check valve 18 has a higher specific gravity than the refrigerant liquid and does not float, the chattering phenomenon is prevented as much as possible.

In this embodiment, an example has been described in which the auxiliary pressure reducing element 42 is provided in the bypass pipe 41 to prevent the chattering phenomenon of the check valve. It has been found that this chattering phenomenon occurs until the refrigerant pressure in each refrigerant pipe at the time of startup is stabilized to some extent. For this reason, without providing the auxiliary pressure reducing element 42 of this embodiment, the control device 12 for controlling the on-off valve 17 is a long pipe and is operated from the start of the operation of the compressor 5 at the start of the heating operation (at the start). The on-off valve 17 may be opened for a predetermined time, for example, 3 minutes and 30 seconds [the time when the refrigerant pressure of each refrigerant pipe is stabilized to some extent] to prevent the chattering phenomenon.

Further, as the auxiliary pressure reducing element 42, a capillary tube or a pipe whose path is crushed may be used.

[0025]

The present invention comprises a compressor, a four-way valve, an outdoor heat exchanger, a main pressure reducing element, a heating pressure reducing element through which refrigerant flows during heating operation, and a check valve which is closed during heating operation and opened during cooling operation. In a separation type air conditioner in which a heat pump cycle is formed by connecting an outdoor unit having a built-in parallel circuit and an indoor unit having a built-in indoor heat exchanger by piping between units, a refrigerant bypasses the parallel circuit. A bypass pipe is provided, and the on-off valve opened during the heating operation and the auxiliary pressure reducing element are provided on the bypass pipe. Therefore, when the on-off valve is opened at the start of the heating operation, the bypass pipe and the parallel circuit are opened by the auxiliary pressure reducing element. Since the pressure on the upstream side is kept higher than the pressure on the downstream side, pressure is applied in the direction in which the check valve closes, and chattering of the check valve is prevented.

[Brief description of the drawings]

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

FIG. 2 is a perspective view of an essential part showing an outdoor unit of the separation type air conditioner.

FIG. 3 is a sectional view showing a check valve of the separation type air conditioner.

FIG. 4 is a main part refrigerant circuit diagram showing a conventional separation type air conditioner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Separation type air conditioner 2 Outdoor unit 3 Unit piping 4 Indoor unit 5 Compressor 6 Four-way valve 7 Outdoor heat exchanger 13 Indoor heat exchanger 15 Main pressure reducing element 16 Heating pressure reducing element 17 On-off valve 18 Check valve 40 Parallel Circuit 41 Bypass pipe 42 Auxiliary pressure reducing element

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F24F 5/00

Claims (1)

(57) [Claims] 1. A parallel circuit comprising a compressor, a four-way valve, an outdoor heat exchanger, a main pressure reducing element, a heating pressure reducing element through which refrigerant flows during heating operation, and a check valve closed during heating operation and opened during cooling operation. Built-in and suction side pipe of compressor
Stores excess refrigerant due to differences in piping length between units.
A heat pump cycle was configured by connecting an outdoor unit connected to a tank such as an accumulator and an indoor unit incorporating an indoor heat exchanger by piping between the units.
In such a case, a bypass pipe through which a refrigerant bypasses the parallel circuit is provided to prevent chattering of the check valve.
A mechanism for generating a pressure difference between the inlet and the outlet of the check valve; and
Pipe line with on- off valve opened during heating operation with long piping connection
The separation type air conditioner , wherein the bypass pipe is constituted by: