JPH0754208B2 - air conditioner - Google Patents

Description

TECHNICAL FIELD The present invention relates to an air conditioner, and more particularly to a refrigerant heating type air conditioner having a burner for heating a refrigerant during heating.

<Problems to be Solved by Conventional Techniques and Inventions> Conventionally, as an air conditioner for performing winter heating and summer cooling with the same device, a pair of heat exchangers arranged indoors and outdoors and between both heat exchangers are used. A compressor for circulating the refrigerant in and a four-way valve for reversing the flow of the refrigerant between both heat exchangers are provided, and by switching the four-way valve, the heat exchanger on the indoor side is condensed by the refrigerant during heating. A so-called heat pump type is used in which the heat exchanger on the outside and the heat exchanger on the outdoor side are used as the evaporator, and the heat exchanger on the indoor side is used as the refrigerant evaporator and the heat exchanger on the outdoor side is used as the condenser during cooling. ing.

However, in this heat pump type air conditioner, the efficiency of the heating function is generally low, depending on the type of the refrigerant and the capacity of the compressor, and particularly when the outdoor air temperature becomes lower than a certain temperature range (around 7 ° C). However, there is a problem in that the vaporization of the refrigerant in the outdoor heat exchanger becomes insufficient and the heating capacity becomes insufficient.

Therefore, various air conditioners equipped with burners for forcibly heating and vaporizing the refrigerant during winter heating have been developed.

For example, the air conditioner shown in FIG. 2 (a) has an indoor heat exchanger (R3) arranged in an indoor unit (U3), a four-way valve (V4) arranged in an outdoor unit (U4), and an accumulator (A2). ), A compressor (P3), an outdoor heat exchanger (R4) and a capillary (C2), in the middle of the heat pump refrigerant circuit (S3), a burner (B2) for heating the refrigerant, an accumulator (A3), and a compact compressor. Circuit (S with a machine (P4)
A refrigerant heating unit (U5) having 4) is inserted, and it has both a normal heat pump type cooling and heating function and a heating function by refrigerant heating.

The air conditioner shown in Fig. 2 (b) is an indoor unit (U
Indoor heat exchanger (R3) arranged in 3), four-way valve (V4) arranged in outdoor unit (U4), accumulator (A
2), the compressor (P3), the outdoor heat exchanger (R4), and the capillary (C2), of the heat pump refrigerant circuit (S5), the capillary (C2) is located at the outdoor unit (U4) side.
A branch circuit (S6) is provided from the downstream side to the upstream side of the accumulator (A2) via the burner (B2) for heating the refrigerant, and is the same for both heat pump cooling and heating and refrigerant heating. Accumulator (A2) and compressor (P3)
Is shared to simplify the mechanism.

The air conditioner shown in FIG. 2 (c) has a first indoor heat exchanger (R3 ') arranged in the indoor unit (U3) and a compressor (P3) arranged in the outdoor unit (U4). , A heat pump type cooling only circuit (S7) consisting of an outdoor heat exchanger (R4) and a capillary (C2), and an indoor unit (U
The second indoor heat exchanger (R3 ″) arranged in 3), the capillary (C3) arranged in the refrigerant heating unit (U5), the burner (B2) for heating the refrigerant, the accumulator (A3) and the small size It has two dedicated circuits, a refrigerant heating type heating dedicated circuit (S8) consisting of a compressor (P4).

However, the air conditioner of FIG. 2 (a) has a heat pump type heating function with poor heating efficiency and a high running cost, although it has a refrigerant heating type heating function with good heating efficiency. Therefore, there is much waste in the mechanism.

In the air conditioner of FIG. 2 (b), similarly, although it has an efficient heating function by heating the refrigerant, it has a waste of having a heat pump type heating function, and a refrigerant that does not require a very large compression capacity. Even when heating, a heat pump type cooling and heating compressor (P3) with a large capacity must be used, which further raises the running cost.

In the air conditioner of FIG. 2 (c), the heating function of the heat pump type is omitted, the mechanism has no waste, and when the refrigerant is heated, it is sufficient to operate the compressor (P4) having a small capacity. Although the running cost is low, there is a problem that the initial cost is high as a whole because two indoor heat exchangers (R3 ') (R3 ") are required.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an air conditioner that has a simple structure, has no wasteful mechanism, and can perform efficient cooling and heating.

<Means for Solving the Problem> An air conditioner of the present invention for solving the above problem is provided with at least one accumulator, a compressor, an outdoor heat exchanger, and a capillary from the one end side of the indoor heat exchanger. A cooling refrigerant circuit reaching the other end of the indoor heat exchanger, and a first branch circuit connected from the other end of the indoor heat exchanger to the upstream side of the accumulator through at least a burner for heating the refrigerant. A second branch circuit connected from the downstream side of the accumulator to one end side of the indoor heat exchanger via a small closed compressor, the first branch circuit, the accumulator, and the second branch circuit. By these, a refrigerant circuit for heating from the other end side to the one end side of the indoor heat exchanger is configured.

<Operation> In the air conditioner of the present invention having the above configuration, during cooling, normal heat pump type cooling is performed using the refrigerant circuit for cooling having the same configuration as conventional, and during heating,
Efficient refrigerant heating type heating is performed using the heating refrigerant circuit provided with a small-sized closed compressor that shares the indoor heat exchanger and the accumulator with the cooling refrigerant circuit.

<Example> The present invention will be described below with reference to FIG. 1 showing an example.

The air conditioner of this embodiment, as shown by the white arrow in the figure,
From the one end side of the indoor heat exchanger (R1) provided in the indoor unit (U1), the forward circuit (S1a), the outdoor heat exchanger (R2) provided in the outdoor unit (U2), and the return circuit (S1b) ) And the refrigerant circuit (S1) for cooling that reaches the other end side of the indoor heat exchanger (R1) and the other end side of the indoor heat exchanger (R1) as indicated by the black arrow in the figure. Exit from the first branch circuit (S2a)
And the accumulator (A1) provided in the forward circuit (S1a)
And a refrigerant circuit (S2) for heating that reaches one end of the indoor heat exchanger (R1) via the second branch circuit (S2b).

Of the refrigerant circuit (S1) for cooling, the forward circuit (S1a)
Stop valve (K1), in order from one end of the indoor heat exchanger (R1),
A solenoid valve (V1), accumulator (A1), receiver tank (T1), and compressor (P1) for refrigerant compression are arranged, and the return circuit (S1b) has an outlet side of the outdoor heat exchanger (R2). A capillary (C1), a solenoid valve (V2) and a stop valve (K2) are arranged in this order from.

Further, the first branch circuit (S2a) of the heating refrigerant circuit (S2) branches from between the stop valve (K2) and the solenoid valve (V2) of the return path (S1b), and the solenoid valve (S2a). V3) and a refrigerant heating burner (B1) are connected to the upstream side of the accumulator (A1) of the outward path (S1a), and the second branch circuit (S2b) is connected to the accumulator of the outward path (S1a). It branches from the position on the downstream side of (A1) and is connected between the solenoid valve (V1) and the stop valve (K1) via a small closed compressor (P2).

Of the solenoid valves (V1) to (V3), the solenoid valve (V1) is opened during the cooling operation, and the indoor heat exchanger (R1) and the accumulator (A1) are directly connected to each other, and the indoor heat exchanger (R1) is connected. ) To guide the vaporized refrigerant to the accumulator (A1), and to prevent the refrigerant vaporized in the burner (B1) from being directly supplied to the indoor heat exchanger (R1) when it is closed during heating operation. Used for. Further, the solenoid valves (V2) (V3) are controlled so that when one is open, the other is closed, so that the other end of the indoor heat exchanger (R1) is connected to the refrigerant circuit (S1). )
Used to connect to either one of (S2).

The accumulator (A1) accumulates an appropriate amount of refrigerant during operation of the air conditioner to make the amount of refrigerant discharged from the compressors (P1) and (P2) constant, or accumulates it internally by external control. By discharging the generated refrigerant, the compressor (P1) (P
It is used to discharge more than the capacity of 2). The receiver tank (T1) is also used to store the liquefied refrigerant.

As the compressor (P1), a compressor with a relatively large capacity is used so that it can be used for normal heat pump type cooling, while as the closed type compressor (P2), refrigerant heating type heating is used efficiently. In order to perform well, a relatively small capacity closed compressor is used, which is the minimum required for refrigerant heating.

Note that the compressor used for refrigerant heating is limited to the closed type because the refrigerant vaporized in the indoor heat exchanger (R1) flows back through the compressor during the heat pump cooling, and the accumulator (A1 ) Is supplied to the receiver tank (T1) without going through.

In order to prevent the backflow of the refrigerant, it is possible to use a combination of a non-closed type compressor and a check valve, but in this combination, the flow of the refrigerant is blocked by the throttle of the check valve. When a small compressor is used, there is a possibility that sufficient compression capacity may not be obtained, and it becomes necessary to upsize the compressor, so that the efficiency of the refrigerant heating system cannot be improved. Therefore, the combination of the non-closed compressor and the check valve is not preferable for the present invention.

As the capillary (C1) for reducing the temperature of the high-temperature high-pressure refrigerant liquefied in the outdoor heat exchanger (R2) to low-temperature low-pressure, depending on the type of refrigerant used and the capacity of the compressor (P1), etc. Those having an inner diameter and a length are used.

Further, as the burner (B1), various combustion systems can be used, and the heating temperature can also be set within an appropriate temperature range depending on the type of solvent used.

The stop valves (K1) (K2) separate the indoor heat exchanger (R1) from the refrigerant circuits (S1) (S2) when the air conditioner is transported or installed, and the indoor units (U1) and outdoor units (U2). ) And (2) are to be separated, both circuits (S1) (S2) are sealed to prevent the loss of refrigerant.

The air conditioner of this embodiment, which is composed of the above parts, is used for cooling and heating as follows.

First, during cooling, the compressor (P1) is operated with the solenoid valves (V1) (V2) opened and the solenoid valve (V3) closed. Then, the refrigerant is discharged as a high-temperature and high-pressure gas from the compressor (P1) as shown by the white arrow, and after the condensation heat is released in the outdoor heat exchanger (R2) to become a high-temperature and high-pressure liquid, After passing through the capillary (C1), the temperature and pressure are reduced, and then supplied to the indoor heat exchanger (R1) via the solenoid valve (V2) and the stop valve (K2). The low-temperature low-pressure liquid refrigerant supplied to the indoor heat exchanger (R1) deprives the heat of vaporization into a low-temperature low-pressure gas, and cools the room at that time. Further, the vaporized low-temperature low-pressure refrigerant is supplied again to the compressor (P1) via the stop valve (K1), the solenoid valve (V1), the accumulator (A1) and the receiver tank (T1), and the above-mentioned again. Used for cycles.

On the other hand, at the time of heating, with the solenoid valves (V1) (V2) closed and the solenoid valve (V3) open, a small closed compressor (P
2) is activated. Then, the refrigerant is discharged as a gas from the closed compressor (P1), as shown by the black arrow,
It is supplied to the indoor heat exchanger (R1) via the stop valve (K1) and releases the heat of condensation inside the indoor heat exchanger (R1) to become a liquid, at which time it heats the room. The liquefied refrigerant is supplied to the burner (B1) via the stop valve (K2) and solenoid valve (V3), heated in the burner (B1) to become gas, and then closed again via the accumulator (A1). Type compressor (P2) and is used again in the above cycle.

Although the air conditioner of the present invention has been described so far based on the above embodiment, the air conditioner of the present invention is not limited to the above embodiment.

For example, in the above embodiment, two solenoid valves (V2) (V3) are used for switching the refrigerant in the branch portion of the cooling refrigerant circuit (S1) and the first branch circuit (S2a), One three-way valve may be used.

Other parts are not limited to the above embodiment,
Various design changes can be made without changing the gist of the present invention.

<Effect> The air conditioner of the present invention is configured as described above and has no heat pump-type heating function, so that there is no waste in the configuration, and a cooling refrigerant circuit and a heating refrigerant circuit are provided. ,
Since the indoor heat exchanger and the accumulator are shared, the structure is simple. Moreover, at the time of cooling, using the refrigerant circuit for cooling having the same configuration as the conventional one, the normal heat pump cooling is performed, and at the time of heating, the refrigerant circuit for heating is provided with a small closed compressor. Thus, efficient refrigerant heating type heating can be performed.

Therefore, the air conditioner of the present invention has a simple structure, has no wasteful mechanism, and is capable of efficient cooling and heating.

[Brief description of drawings]

FIG. 1 is a piping diagram showing an embodiment of the air conditioner of the present invention, and FIGS. 2 (a) to 2 (c) are piping diagrams showing piping of a conventional air conditioner. (A1) …… Accumulator, (B1) …… Burner, (C1) …… Capillary, (P1) …… Compressor, (P2) …… Closed type compressor, (R1) …… Indoor heat exchanger, ( R2) …… Outdoor heat exchanger, (S1) …… Refrigerant circuit for cooling, (S2) …… Refrigerant circuit for heating, (S2a) …… First branch circuit, (S2b) …… Second Branch circuit.

Claims (1)

[Claims] 1. A refrigerant circuit for cooling from one end of the indoor heat exchanger to the other end of the indoor heat exchanger through at least an accumulator, a compressor, an outdoor heat exchanger and a capillary, and an indoor heat. Indoor heat exchange from the other end of the exchanger to the first branch circuit connected to the upstream side of the accumulator via at least the burner for heating the refrigerant, and from the downstream side of the accumulator via the small closed compressor. A second branch circuit connected to one end side of the indoor heat exchanger, the first branch circuit, the accumulator, and the second branch circuit for heating from the other end side to the one end side of the indoor heat exchanger. An air conditioner comprising a refrigerant circuit.