JPH08320172A - Air conditioner - Google Patents

Abstract

PURPOSE: To ensure rapid and effectual defrosting by connecting a discharge side of a compressor and an outdoor heat exchanger with each other through a bypass piping to bypass a four way valve. CONSTITUTION: A compressor 1 and an outdoor heat exchanger are directly connected with other respectively in their discharge side and an outlet side through a bypass piping 11 for bypassing a four way valve 4. The bypass piping 11 serves to directly introduce a refrigerant discharged from the compressor 1 therethrough 11 to the outdoor heat exchanger without changing the position of the four way valve 4 when the operation is changed over from heating operation with use of a heat pump to defrosting operation. Part of refrigerant as discharged from the compressor 1 passes through the bypass piping 11 without passage through the four way valve 4 in such a manner, so that there is no need of changeover of the four way valve from heating operation to defrosting operation. Hereby, rapid and effectual defrosting is ensured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat pump type air conditioner capable of utilizing a boiler heat source as an external heat source during heating.

[0002]

A refrigeration cycle of a heat pump type air conditioner comprises a compressor, an indoor heat exchanger, an expansion valve, an outdoor heat exchanger, and a four-way valve. The four-way valve is used to heat the indoor heat exchange. The container acts as a condenser, and when cooling,
The flow of the refrigerant can be switched so that the indoor heat exchanger acts as an evaporator.

In this type of heat pump type air conditioner, frost may be formed on the outdoor heat exchanger that acts as an evaporator during heating, and if such frost is formed, the heating efficiency is lowered, so it is appropriate. , It is necessary to defrost. When defrosting, the operation mode is switched to the cooling operation by switching the four-way valve, the indoor air is used as a heat source, and the outdoor heat exchanger acts as a condenser to defrost the outdoor heat exchanger. Is going.

On the other hand, as disclosed in Japanese Patent Publication No. 1-25975, a heat pump type air conditioner uses a boiler heat source or the like so that it can be used for heating especially in cold regions. There is also developed a heater provided with the above-mentioned heater to heat the refrigerant. When the defrosting operation is performed using such a heater, rapid defrosting is expected.

Even in this case, when the defrosting operation is performed, the four-way valve is switched, but since the high pressure side and the low pressure side of the refrigerant are reversed during the defrosting operation, when the heating operation is switched to the defrosting operation. In this method, the four-way valve is switched after the compressor is once stopped to reduce the pressure difference between the high pressure and the low pressure in the refrigeration cycle.

[0006]

However, if the four-way valve is switched to switch from the heating operation to the defrosting operation,
In addition to the mechanical noise caused by the switching, there is the inconvenience that a sudden refrigerant pressure difference in the refrigerant causes noise.

Further, when switching from the heating operation to the defrosting operation, it is necessary to temporarily stop the compressor, so that there is a problem that defrosting takes time.

SUMMARY OF THE INVENTION An object of the present invention is to provide an air conditioner which solves the problems of the prior art and enables quick and effective defrosting.

[0009]

In order to achieve the above-mentioned object, the invention according to claim 1 is a refrigerating machine comprising a compressor, a four-way valve, an indoor heat exchanger, an expansion valve and an outdoor heat exchanger. In a cycle, in a heat pump type air conditioner in which a heater utilizing an external heat source such as a boiler is arranged in parallel with the outdoor heat exchanger, the discharge side of the compressor and the outdoor heat exchanger are connected to each other in the four directions. It is characterized in that a bypass pipe for bypassing the valve is provided.

The invention according to claim 2 is a compressor,
A heat pump type air conditioner in which a heater using an external heat source such as a boiler is arranged in parallel with the outdoor heat exchanger in a refrigeration cycle composed of a four-way valve, an indoor heat exchanger, an expansion valve, and an outdoor heat exchanger. In, by providing a bypass pipe connecting the discharge side of the compressor and the outdoor heat exchanger to bypass the four-way valve, and the pipe connecting the outdoor heat exchanger and the heater from the heater A two-way valve for blocking the inflow of the refrigerant into the outdoor heat exchanger is provided.

[0011]

According to the first aspect of the present invention, when the heating operation is switched to the defrosting operation, the refrigerant gas heated by the heater using the external heat source such as the boiler is directly supplied to the outdoor heat exchanger. Install to defrost the outdoor heat exchanger. Thus, by directly introducing the heated refrigerant gas,
Effective defrosting can be done in a short time.

When switching to the defrosting operation, the refrigerant discharged from the compressor is directly introduced into the outdoor heat exchanger through the bypass pipe without switching the position of the four-way valve during the heating operation. .

As described above, since the refrigerant gas does not pass through the four-way valve but passes through the bypass pipe, there is no need to switch the four-way valve, noise is not generated by the switching, and the compressor does not need to be temporarily stopped. Therefore, defrosting can be performed quickly.

According to the invention of claim 2, in addition to the invention of claim 1 described above, during the heating operation by the heater, the refrigerant gas heated by the heater is outdoor by the two-way valve. Prevents entry into the heat exchanger. Therefore, it is possible to reliably prevent the so-called stagnation phenomenon in which the refrigerant circulation amount in the refrigeration cycle is reduced by condensing the refrigerant gas in the outdoor heat exchanger in the low pressure state, and thus it is possible to perform heating with high thermal efficiency by using the boiler heat. .

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an air conditioner according to the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows the refrigeration cycle of the air conditioner according to this embodiment, and the arrows show the flow of the refrigerant during the heating operation.

As shown in FIG. 1, a compressor 1, an indoor heat exchanger 2, an outdoor heat exchanger 3, and a four-way valve 4 are included in the refrigeration cycle.
Is provided. The discharge side of the compressor 1 is connected via a four-way valve 4 to the inlet side of the indoor heat exchanger 2 during heating. Further, the outlet side of the indoor heat exchanger 2 is connected to the inlet side of the outdoor heat exchanger 3 during heating via a third opening / closing valve 7 and a second opening / closing valve 9 used as expansion valves. The outlet side of the outdoor heat exchanger 3 is connected to the four-way valve 4. The two-way valve 10 is opened at the time of heating and at the time of cooling and flows the refrigerant from the outdoor heat exchanger 3 to the four-way valve 4 or vice versa, but is closed at the time of defrosting (which will be described later). Is also used). Further, the four-way valve 4 is connected to the suction side of the compressor 1 to form a refrigeration cycle in which the refrigerant circulates through the indoor heat exchanger 2, the outdoor heat exchanger 3, the four-way valve 4, and the compressor 1.

In such a refrigerant circuit, the heater 5 using the boiler as an external heat source is connected in parallel with the outdoor heat exchanger 3, and the refrigerant is introduced at the inlet side of the heater 5 during use. A first opening / closing valve 8 for permitting is provided, and its outlet side is connected to the suction side of the compressor 1.

In this embodiment, the discharge side of the compressor 1 and the outlet side of the outdoor heat exchanger 3 during heating are directly connected by a bypass pipe 11 that bypasses the four-way valve 4.
A sluice valve 12 that allows or blocks the inflow of the refrigerant is provided in the middle of the bypass pipe 11.

This bypass pipe 11 allows the refrigerant discharged from the compressor 1 to pass through the bypass pipe 11 without switching the position of the four-way valve 4 when switching from the heating operation using a heat pump to the defrosting operation. It is introduced directly into the outdoor heat exchanger 3.

As described above, a part of the refrigerant gas discharged from the compressor 1 during the defrosting operation passes through the bypass pipe 11 without passing through the four-way valve 4, so that the four-way valve 4 changes from the heating operation operation to the defrosting operation. No need to switch. As a result, no noise is generated due to switching of the four-way valve 4, and the compressor does not need to be temporarily stopped, so that defrosting can be performed quickly.

The third opening / closing valve 7, the first opening / closing valve 8, the second
The on-off valve 9 is an indoor heat exchanger 2 connected to each valve,
A valve that is opened when the heater 5 and the outdoor heat exchanger 3 are used and that is closed when not used is used. For the third on-off valve 7 provided downstream of the indoor heat exchanger 2, the flow rate is reduced to an expansion valve. By using a functioning valve, the overall configuration can be simplified.

Next, the operation of this embodiment will be described.

During a heating operation using a normal air heat source, as shown in FIG. 1, the third opening / closing valve 7 and the second opening / closing valve 9 are open and the first opening / closing valve 8 is closed. As indicated by the arrows, the flow of the refrigerant gas is such that the refrigerant gas discharged from the compressor 1 passes through the four-way valve 4 and releases heat when condensed in the indoor heat exchanger 2 which acts as a condenser. 3 After being throttled by the on-off valve 7 and decompressed, it evaporates in the outdoor heat exchanger 3 to take in heat with the outside air, and then flows through the two-way valve 10 and the four-way valve 4 to the suction side of the compressor 1. Return to. During the heating operation by such an air heat source, frost may be formed on the outdoor heat exchanger 3, and if such frost formation occurs, the thermal efficiency decreases and the desired heating effect cannot be obtained, so defrosting is necessary.

The defrosting operation is carried out by introducing the heated refrigerant gas into the outdoor heat exchanger 3 as shown in FIG. 2. In this embodiment, the refrigerant heated by the heater 5 using an external heat source is removed. By introducing it, defrosting can be done quickly and effectively.

When the defrosting operation is performed, the third opening / closing valve 7 and the two-way valve 10 are closed, and the first opening / closing valve 8 and the second opening / closing valve 9 are opened. Further, the sluice valve 12 of the bypass pipe 11 is also opened. Then, the refrigerant gas taken in the boiler heat as the latent heat of vaporization by the heater 5 is sucked into the compressor 1. Then, this refrigerant gas is discharged from the compressor 1 and passes through the bypass pipe 11. Here, since the two-way valve 10 is closed, the frost that is directly sent to the frosted outdoor heat exchanger 3 and frosted on the outdoor heat exchanger 3 by the latent heat of condensation of the refrigerant gas is quickly removed. The refrigerant gas is introduced into the heater 5 through the second opening / closing valve 9 and the first opening / closing valve 8 to be heated.

On the other hand, in the indoor heat exchanger 2, the third opening / closing valve 7
Since a part of the refrigerant gas discharged from the compressor flows in through the four-way valve 4 because it is closed, the state is maintained, so that the rising when the heating operation is restarted after the defrosting is finished. It will be good.

In the heating operation using the boiler heat source, the second opening / closing valve 9 is closed and the first opening / closing valve 8 is opened in FIG. Further, the sluice valve 1 of the bypass pipe 11
2 is closed. In this state, the refrigerant gas forcibly heated by the boiler heat in the refrigerant heating heat exchanger 5 is compressed by the compressor 1
Therefore, in the indoor heat exchanger 2, a larger amount of heat is released and sufficient heating can be performed.

During heating operation using this boiler heat source, the two-way valve 10 blocks the refrigerant gas heated by the heater 5 from flowing into the outdoor heat exchanger 3. Therefore, it is possible to reliably prevent the so-called stagnation phenomenon in which the refrigerant circulation amount in the refrigeration cycle decreases due to the refrigerant gas condensing in the outdoor heat exchanger 3 in a low pressure state, so that heating with good thermal efficiency is performed using the boiler heat. It can be carried out.

The present invention is not limited to the above-mentioned embodiments, but can be variously modified without departing from the gist of the present invention.

For example, in the above-described embodiment, a multi-type air conditioner in which a plurality of indoor heat exchangers 2 and the third opening / closing valve 7 are connected in parallel is used, and when necessary during cooling and heating operations (with load Although the opening degree is adjusted according to the present invention, the present invention is not limited to this, and the same effect can be obtained even when the indoor air conditioner 2 is a single type air conditioner.

[0031]

As is apparent from the above description, according to the invention of claim 1, a heat pump type air conditioner in which a heater using an external heat source such as a boiler is arranged in parallel with the outdoor heat exchanger is provided. In the above, since the bypass pipe connecting the discharge side of the compressor and the outdoor heat exchanger is provided by bypassing the four-way valve, when switching from the heating operation to the defrosting operation, the external heat source such as the boiler is directly connected. The outdoor heat exchanger can be defrosted by the refrigerant gas heated by the used heater,
Effective defrosting can be done in a short time.

Moreover, since the bypass pipe for bypassing the four-way valve is provided, when the heating operation is switched to the defrosting operation, the four-way valve is discharged from the compressor without switching the position of the four-way valve during the heating operation. Since the refrigerant can be directly introduced into the outdoor heat exchanger through the bypass pipe, noise is not generated due to switching, and the compressor does not need to be temporarily stopped, so that defrosting can be performed quickly.

According to the invention of claim 2, in addition to the invention of claim 1 described above, the refrigerant gas heated by the heater is prevented from flowing into the outdoor heat exchanger by the two-way valve. Since it is a configuration that prevents the so-called stagnation phenomenon in which the refrigerant circulation amount in the refrigeration cycle decreases due to the refrigerant gas condensing in the outdoor heat exchanger in a low pressure state, it is possible to reliably use the boiler heat for thermal efficiency. Good heating can be done.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a refrigeration cycle of an air conditioner according to an embodiment of the present invention, and is a diagram showing a flow of a refrigerant gas during heating operation by an air heat source.

FIG. 2 is a circuit diagram showing a refrigeration cycle of an air conditioner according to an embodiment of the present invention, and is a diagram showing a flow of a refrigerant gas during a defrosting operation.

FIG. 3 is a circuit diagram showing a refrigeration cycle of the air conditioner according to the present invention, and is a diagram showing a flow of refrigerant gas during heating operation by an external heat source.

[Explanation of symbols]

 1 Compressor 2 Indoor heat exchanger 3 Outdoor heat exchanger 4 Four-way valve 5 Heater 10 Two-way valve 11 Bypass piping

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koji Nagae 2-5-5 Keihan Hon-dori, Moriguchi City, Osaka Sanyo Electric Co., Ltd.

Claims (2)

[Claims] 1. A refrigeration cycle constituted by a compressor, a four-way valve, an indoor heat exchanger, an expansion valve, and an outdoor heat exchanger, and a heater using an external heat source such as a boiler in parallel with the outdoor heat exchanger. The arranged heat pump type air conditioner is characterized in that a bypass pipe that connects the discharge side of the compressor and the outdoor heat exchanger and bypasses the four-way valve is provided. 2. A refrigeration cycle composed of a compressor, a four-way valve, an indoor heat exchanger, an expansion valve, and an outdoor heat exchanger, and a heater using an external heat source such as a boiler is provided in parallel with the outdoor heat exchanger. In the arranged heat pump type air conditioner, a bypass pipe that connects the discharge side of the compressor and the outdoor heat exchanger and bypasses the four-way valve is provided, and the outdoor heat exchanger and the heater are connected. An air conditioner characterized in that a two-way valve for blocking the inflow of the refrigerant from the heater to the outdoor heat exchanger is provided in the pipe.