JPH0829020A - Heat pump device - Google Patents

Abstract

PURPOSE:To facilitate a proper heating of refrigerant and cause a liquid-phase refrigerant to be hardly sucked into a compressor in response to an amount of the liquid-phase refrigerant contained in refrigerant fed out of an evaporator. CONSTITUTION:A heat pump device in which refrigerant fed out of an evaporator EV is fed into a compressor CMP through an accumulator ACC is comprised of a heating means 2 for heating refrigerant fed out of the evaporator EV and feeding it to the accumulator ACC, and a changing means 3 for changing a heating amount of refrigerant transferred to the accumulator ACC.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat pump device in which a refrigerant discharged from an evaporator is introduced into a compressor via an accumulator.

[0002]

2. Description of the Related Art In a heat pump device, in order to avoid a liquid compression operation of a compressor, a refrigerant discharged from an evaporator is sent to an accumulator, and a gas-phase refrigerant sent from the accumulator is introduced into the compressor. However, when the liquid-phase refrigerant contained in the refrigerant derived from the evaporator is too much, the liquid-phase refrigerant flowing into the accumulator is sucked into the compressor together with the gas-phase refrigerant, and the compressor is a liquid. It is easy to operate in a compressed state, and when a large amount of liquid-phase refrigerant accumulates in the accumulator, the gas-phase refrigerant to be introduced into the compressor is insufficient, and the heat pump device tends to be unable to exhibit its predetermined capacity. Therefore, conventionally, a heating means for heating the refrigerant at a constant or substantially constant heating amount is provided in the refrigerant passage for sending the refrigerant from the evaporator to the accumulator, and the heating means is passed to pass the heating means. The degree is enhanced refrigerant are configured to send to the accumulator.

[0003]

According to the above-mentioned prior art, since the refrigerant passage for feeding the refrigerant from the evaporator to the accumulator is provided with the heating means for heating the refrigerant at a constant or substantially constant heating amount, the cold season. At the start of operation, or at the start of operation immediately after switching the heat exchanger functioning as a condenser to a state of functioning as an evaporator, the liquid-phase refrigerant contained in the refrigerant derived from the evaporator is Even if there are many, if a heating means with a large heating amount capable of rapidly giving a sufficient degree of superheat to these refrigerants is provided, the liquid-phase refrigerant contained in the refrigerant led out from the evaporator is relatively small in the normal amount. In the operating state, there is a drawback in that the refrigerant is excessively superheated and the compressor is easily operated at a high temperature, so that the operation efficiency of the compressor is reduced.

Therefore, in order to solve this drawback, for example, a heating means for heating the liquid-phase refrigerant accumulated in the accumulator is provided so as to be switchable between a heating state and a heating stop state, and included in the refrigerant led out from the evaporator. When the liquid-phase refrigerant accumulates in the accumulator as a result of not being able to give a sufficient degree of superheat to these refrigerants, the accumulated liquid-phase refrigerant is actively heated by the heating means. However, in this case, the liquid-phase refrigerant contained in the refrigerant that could not give a sufficient degree of superheat flows into the accumulator, and moreover, the liquid-phase refrigerant that has accumulated in the accumulator is heated, so it flows into the accumulator. Immediately after the operation, the liquid-phase refrigerant may be sucked into the compressor without being sufficiently heated.

The present invention has been made in view of the above circumstances, and a first object of the present invention is to appropriately adjust the amount of the liquid-phase refrigerant contained in the refrigerant discharged from the evaporator. (EN) It is an object to provide a heat pump device that is easy to heat and that is difficult for a liquid-phase refrigerant to be sucked into a compressor.

A second object of the present invention is to easily heat the refrigerant appropriately according to the amount of the liquid refrigerant contained in the refrigerant discharged from the evaporator, and the liquid refrigerant is used in the compressor. It is to simplify the structure of a heat pump device that is difficult to be sucked.

A third object of the present invention is to more appropriately heat the refrigerant in accordance with the amount of the liquid-phase refrigerant contained in the refrigerant led out from the evaporator, and the liquid-phase refrigerant is a compressor. It is to provide a heat pump device that is hard to be sucked into.

A fourth object of the present invention is to easily heat the refrigerant to a suitable degree according to the amount of the liquid refrigerant contained in the refrigerant discharged from the evaporator, and the liquid refrigerant can be used in the compressor. It is to enable efficient operation of a heat pump device that is difficult to be sucked.

A fifth object of the present invention is to easily heat the refrigerant to a proper degree according to the amount of the liquid-phase refrigerant contained in the refrigerant led out from the evaporator. The object is to enable a heat pump device that is difficult to be sucked in to be efficiently operated in a state where the heat pump device as a whole consumes little energy.

[0010]

A characteristic configuration of the present invention for achieving the above first object is a heat pump device in which a refrigerant drawn from an evaporator is introduced into a compressor via an accumulator, A heating means for heating the refrigerant led out from the evaporator and then sending it to the accumulator, and a changing means for changing the heating amount of the refrigerant sent to the accumulator are provided.

The changing means has a refrigerant passage for sending the refrigerant discharged from the evaporator to the accumulator, a first refrigerant passage provided with the heating means and a second refrigerant passage not provided with the heating means. In the case where the connecting means is provided so as to branch to the evaporator and the accumulator can be selectively connected via the first refrigerant passage or the second refrigerant passage, the second purpose Can be achieved.

The changing means sets the refrigerant passage for sending the refrigerant drawn out from the evaporator to the accumulator to the first refrigerant passage provided with the heating means and the second refrigerant passage not provided with the heating means. The first refrigerant passage and the second refrigerant passage are branched to join the first refrigerant passage and the second refrigerant passage at the downstream side thereof, and the refrigerant discharged from the evaporator is connected to the first refrigerant passage and the second refrigerant passage.
The third object can be achieved by providing the adjusting means capable of adjusting the diversion ratio of the diversion to the refrigerant passage.

In the case where the liquid phase refrigerant detecting means for detecting the liquid phase refrigerant accumulated in the accumulator and the control means for operating the changing means based on the detection result by the liquid phase refrigerant detecting means are provided. The fourth object can be achieved.

When the heating means is provided with heat exchange means for exchanging heat between the refrigerant drawn out from the evaporator and the refrigerant drawn out from the condenser, the fifth object can be achieved.

[0015]

[Operation] By heating the refrigerant drawn from the evaporator,
Although it is possible to send the refrigerant with the superheat degree increased to the accumulator, since the heating amount can be changed according to the amount of the liquid-phase refrigerant contained in the refrigerant derived from the evaporator,
These refrigerants can be appropriately heated, and even if the refrigerant discharged from the evaporator contains a large amount of liquid-phase refrigerant, the refrigerant can be sent to the accumulator after being given a sufficient degree of superheat.

[0016] The changing means sends, to the accumulator, the refrigerant drawn out from the evaporator by a first refrigerant path provided with the heating means and a second refrigerant path not provided with the heating means. In the case where the connecting means is provided to connect the evaporator and the accumulator selectively to each other via the first refrigerant passage or the second refrigerant passage, the evaporator and the accumulator are branched. Is connected via the first refrigerant path, the refrigerant drawn from the evaporator is heated by the heating means, and when the evaporator and the accumulator are connected via the second refrigerant path, the refrigerant drawn from the evaporator is not heated. Therefore, although roughly, the heating amount of the refrigerant sent to the accumulator can be changed according to the amount of the liquid-phase refrigerant contained in the refrigerant led out from the evaporator.

The changing means provides a refrigerant passage for sending the refrigerant discharged from the evaporator to an accumulator to a first refrigerant passage provided with the heating means and a second refrigerant passage not provided with the heating means. The first refrigerant passage and the second refrigerant passage are branched to join the first refrigerant passage and the second refrigerant passage at the downstream side thereof, and the refrigerant discharged from the evaporator is connected to the first refrigerant passage and the second refrigerant passage.
In the case where it is constituted by providing the adjusting means capable of adjusting the diversion ratio for dividing into the refrigerant passage, the refrigerant which has passed through the first refrigerant passage and has been heated and the second refrigerant passage which has not been heated. It is possible to combine the refrigerant with the refrigerant on the downstream side of the refrigerant passages and to send the refrigerant with the superheat degree increased as a whole to the accumulator, but the amount of the refrigerant sent to the first refrigerant passage and heated by the heating means. By adjusting, the heating amount for the entire refrigerant sent to the accumulator can be finely changed.

In the case where the liquid phase refrigerant detecting means for detecting the liquid phase refrigerant accumulated in the accumulator and the control means for operating the changing means based on the detection result by the liquid phase refrigerant detecting means are provided. , You can drive efficiently without any trouble.

If the heating means is provided with heat exchange means for exchanging heat between the refrigerant drawn out from the evaporator and the refrigerant drawn out from the condenser, the heating means is condensed to the refrigerant taken out from the evaporator. To increase the degree of heating of the refrigerant by heating by giving the heat of the refrigerant drawn from the condenser, and cooling by giving the cold heat of the refrigerant drawn from the evaporator to the refrigerant drawn from the condenser, The degree of supercooling of the refrigerant can be increased.

[0020]

According to the heat pump device of the first aspect of the present invention, it is easy to heat the refrigerant appropriately according to the amount of the liquid phase refrigerant contained in the refrigerant led out from the evaporator, and the liquid phase refrigerant is a compressor. Is hard to be sucked into.

In the heat pump device according to the second aspect of the present invention, it is easy to heat the refrigerant appropriately according to the amount of the liquid phase refrigerant contained in the refrigerant led out from the evaporator, and the liquid phase refrigerant is sucked into the compressor. The structure of the heat pump device
For example, this can be simplified as compared with the case where the heating amount of the refrigerant is changed by providing a unit for adjusting the heating amount of the heating unit itself.

In the heat pump device according to the third aspect of the present invention, the refrigerant can be heated more appropriately according to the amount of the liquid-phase refrigerant contained in the refrigerant led out from the evaporator, and the liquid-phase refrigerant can be transferred to the compressor. Hard to be inhaled. In particular, since the heating amount can be finely adjusted by adjusting the diversion ratio for dividing the flow into the first refrigerant passage and the second refrigerant passage, it is possible to change the rotational speed of the compressor, the opening degree of the expansion valve, and the like. There is also an effect that the superheat degree of the refrigerant introduced into the compressor can be easily adjusted without adjusting the circulation amount of the refrigerant.

In the heat pump device according to the fourth aspect of the present invention, the refrigerant is easily heated appropriately according to the amount of the liquid-phase refrigerant contained in the refrigerant led out from the evaporator, and the liquid-phase refrigerant is sucked into the compressor. The heat pump device, which is hard to be damaged, can be operated efficiently.

In the heat pump device according to the fifth aspect of the present invention, the refrigerant is easily heated appropriately according to the amount of the liquid refrigerant contained in the refrigerant drawn out from the evaporator, and the liquid refrigerant is sucked into the compressor. The heat pump device, which is hard to be damaged, can be efficiently operated in a state where the waste of energy as the whole heat pump device is small.

[0025]

【Example】

[First Embodiment] FIGS. 1 and 2 show a heat pump circuit in a cooling operation mode of a heat pump device for air conditioning, which includes an outdoor heat exchanger NO, an outdoor expansion valve VEXO, a receiver RCV, an indoor expansion valve VEXI and an indoor heat exchange. Both ends of the refrigerant passage connecting the vessel NI in order and the ends of the refrigerant passage connecting the accumulator ACC, the compressor CMP and the oil separator OSP in order are connected via the four-way valve 1. By operating valve 1,
It is configured to switch between a cooling operation mode and a heating operation mode.

In the heat pump circuit, a thick black line indicates that the refrigerant in that portion is in a high-pressure vapor phase state, and a thick line hatched indicates that the refrigerant in that portion is in a liquid phase state. The thick line with dot hatching indicates that the refrigerant in that portion is in the gas-liquid two-phase state (wet vapor state), and the thick white line indicates that the refrigerant in that portion is in the low-pressure vapor phase state. Further, in the heat pump circuit, a white valve symbol indicates a state where the valve is open, and a black valve symbol indicates a state where the valve is closed.

In the cooling operation mode shown in FIG. 1 and FIG. 2, the outdoor heat exchanger NO is connected to the oil separator O via the four-way valve 1.
The indoor heat exchanger NI is connected to the refrigerant passage on the downstream side of the SP
Is connected to the upstream refrigerant passage of the accumulator ACC via the four-way valve 1, and the outdoor heat exchanger NO serves as the condenser CD.
The indoor heat exchanger NI functions as an evaporator EV, the outdoor expansion valve VEXO is switched to a state of operating as a flow rate adjusting means VFR, and the indoor expansion valve VEXI is switched to a state of operating as an expanding means EX. There is.

Although not shown, in the heating operation mode,
The outdoor heat exchanger NO is connected to the accumulator A via the four-way valve 1.
The indoor heat exchanger NI is connected to the refrigerant passage on the upstream side of CC
Is connected to the downstream refrigerant passage of the oil separator OSP via the four-way valve 1, the outdoor heat exchanger NO functions as an evaporator EV, and the indoor heat exchanger NI functions as a condenser CD.
The outdoor expansion valve VEXO is switched to a state of operating as the expansion means EX, and the indoor expansion valve VEXI is switched to a state of operating as the flow rate adjusting means VFR.

In any operation mode,
The refrigerant derived from the heat exchanger functioning as the evaporator EV is introduced into the compressor CMP via the accumulator ACC, and the refrigerant derived from the heat exchanger functioning as the condenser CD is passed through the receiver RCV. And is introduced into an expansion valve which acts as expansion means EX.

The refrigerant passage from the four-way valve 1 to the accumulator ACC has a first refrigerant passage R1 provided with a heating means 2 for heating the refrigerant derived from the evaporator EV and then sending it to the accumulator ACC, and a heating means. No. 2 is not provided in the second refrigerant path R2, and the downstream side of the first refrigerant path R1 and the downstream side of the second refrigerant path R2 are connected together before the accumulator ACC and the accumulator ACC.
Change means 3 for changing the heating amount of the refrigerant sent to is provided.

The heating means 2 is a heat exchange device that allows the refrigerant discharged from the evaporator EV to exchange heat with the refrigerant discharged from the condenser CD by passing the middle of the first refrigerant passage R1 into the receiver RCV. Means are provided, and the changing means 3 is an evaporator E.
V and the accumulator ACC are first solenoid valves V1 and second solenoid valves V1 which are opened and closed in an antithetical manner as connecting means which can be selectively connected via the first refrigerant passage R1 or the second refrigerant passage R2. Are provided in the first refrigerant passage R1 and the second refrigerant passage R2.

The accumulator ACC has two exothermic temperature sensors SU, which serve as liquid-phase refrigerant detecting means 4 for detecting the liquid-phase refrigerant RLq accumulated in the accumulator ACC.
SL is provided, and based on the detection results of the liquid-phase refrigerant RLq by these temperature sensors SU, SL, a controller CNT as a control means for opening and closing the first solenoid valve V1 and the second solenoid valve V2 in a contradictory manner. It is provided.

The two temperature sensors SU and SL are vertically spaced from each other with their sensing parts facing the inner wall of the accumulator ACC.
U and SL output a low temperature detection signal to the controller CNT when the liquid level of the liquid-phase refrigerant RLq reaches a predetermined sensing level and the sensing part is cooled by the liquid-phase refrigerant RLq, and the liquid-phase refrigerant RLq
Is connected to output a high temperature detection signal to the controller CNT when the liquid level does not reach a predetermined sensing level and the sensing unit is not cooled.

Since the amount of the liquid-phase refrigerant contained in the refrigerant discharged from the evaporator EV is large, the liquid level of the liquid-phase refrigerant RLq in the accumulator ACC becomes the sensing level of the upper temperature sensor SU arranged on the upper side. When it reaches, the low temperature detection signal is input from the upper temperature sensor SU to the controller CNT, and the controller CNT judges that the superheat degree of the refrigerant derived from the evaporator EV is insufficient, and as shown in FIG. , First solenoid valve V
1 is opened and the second solenoid valve V2 is closed, and the refrigerant derived from the evaporator EV flows through the first refrigerant path R1 and the receiver RCV.
The refrigerant that has been heated by heat exchange with the liquid-phase refrigerant RLq in the inside and has a superheated degree is sent to the accumulator ACC, and
The liquid-phase refrigerant RLq in the receiver RCV is supercooled.

The refrigerant having a high degree of superheat is accumulator A.
As a result of being sent to CC, liquid-phase refrigerant R in accumulator ACC
Lower temperature sensor SL with the liquid level of Lq located below
When the temperature falls below the detection level of, the high temperature detection signal is input from the lower temperature sensor SL to the controller CNT, and the controller CNT judges that the superheat degree of the refrigerant derived from the evaporator EV is within the allowable range. As shown in FIG. 2, the first solenoid valve V1 is closed and the second solenoid valve V2 is opened, and the refrigerant derived from the evaporator EV flows through the second refrigerant passage R2 and accumulator A.
Sent to CC.

[Second Embodiment] FIG. 3 shows an accumulator ACC.
Another embodiment of the changing means 3 for changing the heating amount of the refrigerant sent to is shown. This changing means 3 divides the refrigerant led from the evaporator EV into the first refrigerant passage R1 and the second refrigerant passage R2. A flow dividing valve V3 is provided as an adjusting means capable of adjusting the flow dividing ratio.

The accumulator ACC is of a capacitance type for detecting a change in the liquid level of the liquid phase refrigerant RLq as the liquid phase refrigerant detecting means 4 for detecting the liquid phase refrigerant RLq accumulated in the accumulator ACC. A level sensor S3 is provided, and based on the detection result of the liquid level by the level sensor S3, the refrigerant drawn from the evaporator EV is first
A controller CNT as a control means for operating a diversion valve V3 by calculating a diversion ratio of diversion to the refrigerant passage R1 and the second refrigerant passage R2.
Is provided.

The controller CNT is the accumulator A.
Depending on the liquid level of the liquid-phase refrigerant RLq in the CC, the flow dividing valve V3 is operated by operating the flow dividing valve V3 by calculating the flow dividing ratio such that the higher the liquid level is, the larger the amount of flow is divided into the first refrigerant passage R1. Refrigerant path R
The refrigerant that has flowed through 1 to have an increased degree of superheat and the second refrigerant passage R2
The refrigerant that flowed through the tank and was not heated is the accumulator ACC
Before joining, they are mixed and sent to the accumulator ACC in a mixed state so as to have an appropriate superheat degree as a whole. Other configurations are the same as in the first embodiment.

Other Embodiments 1. The heating means that heats the refrigerant drawn from the evaporator and then sends it to the accumulator may be one that heats the refrigerant by heat exchange with outdoor air or indoor air. 2. The changing means for changing the heating amount of the refrigerant sent to the accumulator branches the refrigerant path for sending the refrigerant derived from the evaporator to the accumulator into a plurality of branch refrigerant paths, and each of these branch refrigerant paths or two or more of them. Means for changing the heating amount by providing heating means having different heating amounts, selecting one or more of these branch refrigerant passages, and connecting the evaporator and the accumulator with the selected branch refrigerant passages. Alternatively, it may be a means for changing the heating amount by adjusting the diversion ratio of diversion to these branched refrigerant passages. 3. The changing means for changing the heating amount of the refrigerant sent to the accumulator may be one that switches the heating means between the heating state and the heating stopped state by a manual operation. 4. The heat pump device according to the present invention is not limited to air conditioning applications such as cooling and heating, but can be applied to various applications in various fields dealing with cold heat and hot heat.

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the structures of the accompanying drawings by the entry.

[Brief description of drawings]

[Figure 1] Heat pump circuit diagram

[Figure 2] Heat pump circuit diagram

FIG. 3 is a heat pump circuit diagram showing a second embodiment.

[Explanation of symbols]

 2 heating means 3 changing means 4 liquid phase refrigerant detecting means ACC accumulator CD condenser CMP compressor CNT control means EV evaporator R1 first refrigerant passage R2 second refrigerant passage V1 connecting means V2 connecting means V3 adjusting means

Claims (5)

[Claims] 1. A heat pump device in which a refrigerant derived from an evaporator (EV) is introduced into a compressor (CMP) via an accumulator (ACC), wherein the refrigerant derived from the evaporator (EV) is Heating means (2) for heating and then sending it to the accumulator (ACC);
A heat pump device provided with a changing means (3) for changing the heating amount of the refrigerant sent to the accumulator (ACC). 2. The evaporator (E) is provided with the changing means (3).
V) the refrigerant derived from the accumulator (ACC)
The refrigerant passage sent to the first refrigerant passage (R1) provided with the heating means (2) and the second refrigerant passage (R2) not provided with the heating means (2), and the evaporation is performed. A connecting means (V1, V2) for selectively connecting the container (EV) and the accumulator (ACC) via the first refrigerant passage (R1) or the second refrigerant passage (R2). The heat pump device according to claim 1. 3. The changing means (3) comprises the evaporator (E).
The refrigerant passage for sending the refrigerant derived from V) to the accumulator (ACC) is the first refrigerant passage (R1) provided with the heating means (2) and the second refrigerant passage not provided with the heating means (2). To the first refrigerant passage (R1).
) And the second refrigerant passage (R2) are joined together at the downstream side thereof, and the refrigerant derived from the evaporator (EV) is connected to the first refrigerant passage (R1) and the second refrigerant passage (R2).
2. The heat pump device according to claim 1, further comprising adjusting means (V3) capable of adjusting a diversion ratio of the diversion. 4. A liquid-phase refrigerant detecting means (4) for detecting a liquid-phase refrigerant accumulated in the accumulator (ACC), and the changing means (3) based on a detection result by the liquid-phase refrigerant detecting means (4). 4. The heat pump device according to claim 2, further comprising a control means (CNT) for operating the heat pump. 5. The evaporator (E) is provided by the heating means (2).
5. The heat pump apparatus according to claim 1, wherein the heat pump device is provided with heat exchange means for exchanging heat between the refrigerant led out of V) and the refrigerant led out of the condenser (CD).