JPH07301466A - Plural-stage heat pump apparatus - Google Patents

Abstract

PURPOSE:To prevent a decrease in a compressing efficiency by opposing the end opening faces of a high pressure side circulating passage and a low pressure side circulating passage, and reversing a direction in which refrigerant of a wet vapor state flows out from a channel end opening face and a direction in which refrigerant of a superheated vapor state flows out from a channel end opening face to each other. CONSTITUTION:Refrigerant taken out in a vapor state from an intermediate cooler 3 is fed to a high pressure side refrigerant circuit, and refrigerant taken out in a liquid state of a wet vapor state is fed to a low pressure side refrigerant circuit from the cooler 3. The refrigerant of a superheated vapor state is returned to the cooler 3 by a low pressure side circulating system. In such a plural stage heat pump apparatus, the end opening face 4b of a high pressure side circulating passage 4 for returning the refrigerant in a wet vapor state to the cooler 3 is opposed in a proximity state to the end opening face 5b of a low pressure side circulating passage 5 for returning the refrigerant in a superheat vapor state to the cooler 3, and the refrigerants reversely communicate with each other. Thus, heat exchanging of the refrigerant of the wet vapor state with the refrigerant of the superheated vapor state is expedited.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention allows a refrigerant taken out from an intercooler in a vapor phase state to pass through a high pressure side compressor, a condenser and a high pressure side expansion means in this order, and then to the intercooler in a wet vapor state. The high pressure side circulation system to be returned and the refrigerant taken out in the liquid phase state from the intercooler are passed through the low pressure side expansion means, the evaporator and the low pressure side compressor in this order, and returned to the intercooler in the superheated gas phase state. The present invention relates to a multi-stage heat pump device including a side circulation system.

[0002]

2. Description of the Related Art A multi-stage heat pump device of this type returns a refrigerant in a wet vapor state from a high pressure side expansion means and a refrigerant in a superheated gas phase state from a low pressure side compressor to an intermediate cooler for heat exchange. As a result, the temperature of the refrigerant supplied to the high-pressure side compressor is lowered, so compared to a single-stage heat pump device equipped with a single refrigerant circulation system, it is possible to prevent a decrease in compression efficiency due to the compressor and at the same time, It is possible to reduce the temperature of the refrigerant discharged from the compressor, and suppress the deterioration of the lubricating oil used in the high-pressure side compressor.

Conventionally, as shown in FIG. 6, when the refrigerant in the wet vapor state and the refrigerant in the superheated gas phase are directly heat-exchanged in the intermediate cooler 01, the refrigerant in the wet vapor state is transferred from the high pressure side expansion means to the intermediate state. The high pressure side return path 02 for returning to the internal gas phase area GA of the cooler 01 and the low pressure side return path 0 for returning the refrigerant in a superheated gas phase state from the low pressure side compressor to the internal gas phase area GA of the intercooler 01.
3 and 3 are connected to the inner wall 04 of the intercooler 01 so that their opening surfaces 05 and 06 are formed on the inner surface of the inner wall.
Each of the refrigerant in the wet vapor state and the refrigerant in the superheated gas phase is caused to individually flow into the intercooler 01 through their opening faces 05 and 06, and these refrigerants spontaneously move in the intercooler 01. Heat is directly exchanged by contacting each other while mixing with each other. In the figure, reference numeral 07 denotes a gas-phase refrigerant discharge path for discharging the refrigerant in the gas-phase state after heat exchange to the high-pressure side compressor, 08 denotes the refrigerant in the liquid-phase state after heat exchange to the low-pressure side expansion means. It is a liquid-phase refrigerant outlet path to be led out.

[0004]

Therefore, heat exchange between the refrigerant in the wet vapor state and the refrigerant in the superheated vapor phase state is insufficient, and the refrigerant in the superheated vapor phase state is supplied to the high pressure side compressor without being sufficiently cooled. Therefore, the temperature of the refrigerant supplied to the high-pressure side compressor is hard to be lowered sufficiently, and there is a drawback that the reduction of compression efficiency due to the compressor cannot be effectively prevented.

In addition, due to insufficient heat exchange between the refrigerant in the wet vapor state and the refrigerant in the superheated vapor phase state, the liquid component of the refrigerant in the wet vapor state is not sufficiently heated and is on the high pressure side. It is easy to be sucked into the compressor, and the operating energy of the high-pressure side compressor is wastefully consumed to evaporate such a liquid component, and the high-pressure side compressor required to compress the supplied refrigerant to a predetermined pressure. In addition, there is a drawback that the operating energy is increased, and when the high-pressure side compressor is operated in a liquid compression state, the high-pressure side compressor is easily damaged.

The present invention has been made in view of the above-mentioned circumstances, and is devised by devising a means for causing each of the refrigerant in a wet vapor state and the refrigerant in a superheated vapor phase state to flow into the intercooler. The heat exchange between the refrigerant in the superheated state and the refrigerant in the superheated gas phase state can be promoted to effectively prevent the compression efficiency from being lowered by the compressor, and further, the operating energy of the high-pressure side compressor is not likely to increase or be damaged. It is an object to provide a multi-stage heat pump device.

It is another object of the present invention to increase the contact probability between the refrigerant in the wet vapor state and the refrigerant in the superheated gas phase state to efficiently promote heat exchange between these refrigerants.

Another object of the present invention is to facilitate the stirring and mixing of the wet vapor state refrigerant and the superheated vapor phase state refrigerant so as to efficiently promote heat exchange between these refrigerants.

Another object of the present invention is to efficiently separate the liquid content from the refrigerant in the wet vapor state so as to effectively prevent an increase in operating energy of the high-pressure side compressor and its damage. And

[0010]

To achieve the above object, the present invention is characterized in that a refrigerant taken out in a vapor phase from an intercooler is passed through a high pressure side compressor, a condenser and a high pressure side expansion means in this order. Then, the high-pressure side circulation system returning to the intercooler in the wet vapor state, and the refrigerant taken out in the liquid phase state from the intercooler is passed through the low-pressure side expansion means, the evaporator, and the low-pressure side compressor in this order, A multi-stage heat pump device comprising a low pressure side circulation system returned to the intercooler in a superheated gas phase state,
A road end opening surface of a high pressure side return path that returns the refrigerant from the high pressure side expansion means to the intercooler in a wet vapor state, and a low pressure side that returns the refrigerant from the low pressure side compressor to the intercooler in a superheated gas phase state. The point is that the path end opening surface of the return path is opposed in close proximity in the internal gas phase region of the intercooler.

Each of the road end portion of the high-pressure side return passage and the road end portion of the low-pressure side return passage is formed in a hood shape whose diameter increases toward the road end opening surface side, and the enlarged diameter road end opening surfaces are connected to each other. When the two are closely opposed to each other, it is possible to increase the contact probability between the refrigerant in the wet vapor state and the refrigerant in the superheated vapor phase state, and efficiently promote heat exchange between these refrigerants.

In the case where each of the road end opening surface of the high pressure side return passage and the road end opening surface of the low pressure side return passage is divided into a plurality of parts and dispersed in the internal gas phase region of the intercooler. The refrigerant in the wet vapor state and the refrigerant in the superheated vapor phase state are easily agitated and mixed, and heat exchange between these refrigerants can be efficiently promoted.

When the road end opening surface of the high pressure side return passage and the road end opening surface of the low pressure side return passage are opposed to each other in the longitudinal axis direction of the vertically formed intercooler, a wet steam state is obtained. It is possible to effectively separate the liquid content from the refrigerant, and effectively prevent an increase in operating energy of the high-pressure side compressor and its damage.

[0014]

[Function] Since the road end opening surface of the high pressure side return path and the road end opening surface of the low pressure side return path are opposed to each other, the direction in which the refrigerant in the wet vapor state flows out from the road end opening surface and the superheated gas phase state The refrigerant flows out from the road end opening face in opposite directions, and since the road end opening faces are close to each other, the refrigerant in the wet vapor state and the refrigerant in the superheated vapor phase state are mutually opposite. The refrigerant efficiently mixes and is mixed while exchanging heat, and these mixed refrigerants further flow into the internal gas phase region of the intercooler from between the road end opening surfaces.

Therefore, heat exchange between the refrigerant in the wet vapor state and the refrigerant in the superheated vapor phase state is promoted by positively colliding and mixing the refrigerants before they flow into the intercooler. Also, since the refrigerant flowing into the intercooler from between the road end openings is already mixed by the collision prior to the inflow to the intercooler, the heat of the refrigerant even in the intercooler flows. Exchange is further promoted.

As a result of heat exchange between the refrigerant in the wet vapor state and the refrigerant in the superheated gas phase being promoted, even the liquid content of the refrigerant in the wet vapor state is relatively light and easily sucked into the high pressure side compressor. Since fine liquid components easily evaporate, the supply of such liquid components to the high-pressure side compressor can also be suppressed.

Each of the road end portion of the high pressure side return passage and the road end portion of the low pressure side return passage is formed in a hood shape whose diameter increases toward the road end opening surface side, and the enlarged diameter road end opening surfaces are close to each other. When they are opposed to each other, the collision region between the wet vapor state refrigerant and the superheated gas state refrigerant becomes wider.

When each of the road end opening surface of the high pressure side return path and the road end opening surface of the low pressure side return path is divided into a plurality of parts and dispersed in the internal gas phase region of the intercooler, the wetness While setting the collision region between the refrigerant in the vapor state and the refrigerant in the superheated vapor phase state as wide as possible, it is possible to suppress the decrease in the discharge speed of these refrigerants from the road end opening surface, so that the refrigerant in the wet vapor state and the superheated vapor phase The refrigerant in the state can be agitated and mixed with each other in such a state that the refrigerant intrudes deeply in the direction opposite to the road end opening surface.

When the road end opening surface of the high pressure side return passage and the road end opening surface of the low pressure side return passage are opposed to each other in the longitudinal axis direction of the vertically formed intercooler, between the road end opening surfaces. The wall of the intercooler is located near the lateral side of the tank along the vertical direction, and the refrigerant that is about to flow into the internal gas phase region of the intercooler from between the road end openings is on the wall. Since it is blown out toward the vessel wall, a liquid component having a large inertial force in the refrigerant blown toward the vessel wall collides with the vessel wall inner surface of the intercooler, and tends to adhere and aggregate on the vessel wall inner surface.

[0020]

The multi-stage heat pump device according to claim 1 can promote heat exchange between the refrigerant in the wet vapor state and the refrigerant in the superheated gas phase state, and sufficiently cool the refrigerant in the superheated gas phase state. Since it is easy to supply the high-pressure side compressor to the high-pressure side compressor, the temperature of the refrigerant supplied to the high-pressure side compressor is easily lowered, and the reduction of the compression efficiency by the compressor can be effectively prevented.

In addition, the refrigerant in the wet vapor state and the refrigerant in the superheated vapor phase state are positively collided with each other before flowing into the intercooler to promote heat exchange between them, so that heat exchange between the refrigerants is performed. Since it is possible to suppress the supply of the liquid of the refrigerant in the wet vapor state to the high-pressure side compressor due to the insufficient amount, it is unlikely that the operating energy of the high-pressure side compressor increases or the damage thereof.

The multi-stage heat pump device according to claim 2 is
The probability of contact between the refrigerant in the wet vapor state and the refrigerant in the superheated vapor phase state is high, and heat exchange between these refrigerants can be efficiently promoted.

The multi-stage heat pump device according to claim 3 is
The refrigerant in the wet vapor state and the refrigerant in the superheated vapor phase state are easily stirred and mixed, and heat exchange between these refrigerants can be efficiently promoted.

The multi-stage heat pump device according to claim 4 is
Efficiently separates the liquid component of the refrigerant in the wet vapor state,
It is possible to effectively prevent an increase in operating energy of the high-pressure side compressor and its damage.

[0025]

【Example】

[First Embodiment] FIGS. 2 and 3 show an air conditioner as an example of a multi-stage heat pump device, which includes an outdoor heat exchanger 1 for absorbing and radiating outdoor air A1, and an outdoor air exchanger 1 having outdoor air A1.
1, an outdoor air fan F1 that ventilates 1, an indoor heat exchanger 2 that cools and heats indoor air, and an air supply fan F2 that sends the air A2 adjusted by the indoor heat exchanger 2 to an air conditioning target area. By circulating the refrigerant between the outdoor heat exchanger 1 and the indoor heat exchanger 2, the outdoor air A1 is used as a heat absorption / radiation source,
A two-stage compression heat pump circuit that cools or heats indoor air is configured.

In the two-stage compression heat pump circuit, the thick black line indicates that the refrigerant state of that portion is the high-pressure vapor phase, and the thick hatched line indicates that the refrigerant state of that portion is the liquid phase. , The thick line with dot hatching indicates that the refrigerant state of that part is gas-liquid two-phase (wet vapor), and the white thick line indicates that the refrigerant state of that part is low-pressure gas phase. There is.

In the two-stage compression heat pump circuit, a first expansion valve ex1 for the outdoor heat exchanger 1, a second expansion valve ex2 for the indoor heat exchanger 2, a high pressure side compressor CmH and a low pressure side compressor CmL. Two compressors, the two compressors CmH and CmL, the intercooler 3 to which the first expansion valve ex1 and the second expansion valve ex2 are connected, and the high-pressure side compressor Cm.
First and second solenoid valves V1 and V2 that can selectively introduce the high-pressure gas-phase refrigerant that is derived from H into the outdoor heat exchanger 1 or the indoor heat exchanger 2 according to the air conditioning mode, and the air conditioning mode The third and fourth solenoid valves V3 and V4 that can introduce the low-pressure gas-phase refrigerant that is discharged from the outdoor heat exchanger 1 or the indoor heat exchanger 2 into the low-pressure side compressor CmL are provided. .

The first expansion valve ex1 and the second expansion valve ex2
When either the outdoor heat exchanger 1 or the indoor heat exchanger 2 functions as the evaporator E, the first heat exchanger corresponding to the heat exchanger that functions as the evaporator E is provided between the intermediate cooler 3 and the intercooler 3. The fifth and sixth electromagnetic valves V5 and V6 capable of switching the flow paths so that the expansion valve ex1 or the second expansion valve ex2 functions as the low-pressure side expansion means, and the outdoor heat exchanger 1 or the indoor heat exchanger 2
When causing the other of the above to function as the condenser C,
The first corresponding to the heat exchanger to function as the condenser C
The seventh and eighth electromagnetic valves V whose flow paths can be switched so that the expansion valve ex1 or the second expansion valve ex2 functions as the high-pressure side expansion means.
7 and V8 are provided.

The intercooler 3 is constructed by providing a vertically long cylindrical tank, and the refrigerant in a wet vapor state that has passed through the first expansion valve ex1 or the second expansion valve ex2 that functions as high-pressure side expansion means is intercooled. Wet steam introduced from the high pressure side return passage 4 is connected to the high pressure side return passage 4 for returning the refrigerant to the low pressure side return passage 5 for returning the refrigerant from the low pressure side compressor CmL to the intercooler 3 in a superheated gas phase state. The refrigerant in the state and the refrigerant in the superheated gas phase introduced from the low pressure side return passage 5 are directly heat-exchanged in the intercooler 3, and the refrigerant in the gas phase after heat exchange is opened to the top of the tank. State, the refrigerant in the liquid phase after being discharged to the high-pressure side compressor CmH from the first discharge path 6 connected in a communicating state and being heat-exchanged is connected to the second discharge path 7 connected in a state of opening at the tank bottom to the low pressure side. First expansion valve e functioning as expansion means
x1 or the second expansion valve ex2.

In the figure, the open solenoid valve shows the open state, and the black solenoid valve shows the closed state.

FIG. 2 shows the two-stage compression heat pump circuit in a state where the air conditioning mode is switched to the cooling mode. In this cooling mode, the second solenoid valve V2, the third solenoid valve V3, the fifth solenoid valve V5, and the eighth solenoid valve V5. The solenoid valve V8 is closed, and the first solenoid valve V1, the fourth solenoid valve V4, the sixth solenoid valve V6, and the seventh solenoid valve V7 are opened to compress the refrigerant taken out from the intercooler 3 in the vapor phase on the high pressure side. Machine CmH / outdoor heat exchanger 1 functioning as condenser C / first expansion valve e as high pressure side expansion means
x1 and the second high-pressure side circulation system for returning to the intercooler 3 in the wet vapor state, and the second expansion valve ex2 as the low-pressure side expansion means for the refrigerant taken out from the intercooler 3 in the liquid phase state.
The indoor heat exchanger 2 that functions as the evaporator E and the low-pressure side compressor CmL are passed in this order, and the low-pressure side circulation system that returns to the intercooler 3 in the superheated gas phase state is configured.

FIG. 3 shows the two-stage compression heat pump circuit in a state where the air conditioning mode is switched to the heating mode. In this heating mode, the second solenoid valve V2, the third solenoid valve V3, and the fifth solenoid valve V5 are connected. The eighth solenoid valve V8 is opened, and the first solenoid valve V1, the fourth solenoid valve V4, the sixth solenoid valve V6, and the seventh solenoid valve V7 are closed, so that the refrigerant taken out from the intercooler 3 in a gas phase state has a high pressure. The side compressor CmH, the indoor heat exchanger 2 functioning as the condenser C, and the second expansion valve ex2 as the high-pressure side expansion means are passed in this order, and the intercooler 3 is in a wet vapor state.
And the first expansion valve ex as the low pressure side expansion means for the high pressure side circulation system for returning to the low temperature side and the refrigerant taken out from the intercooler 3 in the liquid phase state.
1. A low-pressure side circulation system that passes through the outdoor heat exchanger 1 that functions as the evaporator E and the low-pressure side compressor CmL in this order and returns to the intercooler 3 in the superheated gas phase state.

As shown in FIG. 1, each of the high-pressure side return passage 4 and the low-pressure side return passage 5 is constructed by connecting a pipe to the device wall 3a of the intercooler 3 in a penetrating state. Roadside 4
a and the road end portion 5a of the low-pressure side return passage 5 are formed in a hood shape in which the road end opening surface side is expanded in a spherical shape to form enlarged diameter road end opening surfaces 4b and 5b. Opening surface 4b,
5b are positioned in the internal gas phase region GA of the intercooler 3 such that the road end opening surface 5b of the low pressure side return passage 5 is located on the upper side and the road end opening surface 4b of the high pressure side return passage 4 is located on the lower side. In the close state, they are concentrically opposed to the longitudinal axis X of the intercooler 3.

The outdoor heat exchanger 1 functioning as an evaporator
Alternatively, a low-temperature low-pressure gas phase refrigerant having a low temperature may be provided in the middle of the refrigerant flow path 8 for discharging the low-temperature low-pressure gas phase refrigerant discharged through the indoor heat exchanger 2 to the low-pressure side compressor CmL. The heat exchanger 9 for exchanging heat with the refrigerant in the liquid phase accumulated at the bottom of the intercooler 3 is provided, and the refrigerant in the liquid phase discharged from the second outlet passage 7 is in the low-pressure gas phase state with a low temperature. Since it is cooled by the refrigerant, the first expansion valve ex1 functions as a low-pressure side expansion means for the refrigerant in a supercooled state in which the liquid state is stable.
Alternatively, it can be supplied to the second expansion valve ex2, and there is an effect that the decompression expansion by the low pressure side expansion means can be stabilized.

[Second Embodiment] FIG. 4 shows another embodiment of the road end opening surface, showing the road end opening surface 4b of the high pressure side return path 4 and the road end opening surface 5b of the low pressure side return path 5, respectively. Are divided into a plurality of parts and are dispersedly arranged in the internal gas phase region GA of the intercooler 3.

In each of the road end opening surfaces 4b and 5b, the road end portions 4a and 5a of the high pressure side return path 4 and the low pressure side return path 5 are constituted by a plurality of branch pipes 4c and 5c, respectively. It is divided into a plurality of branch passage end opening surfaces 4d and 5d each having an opening at the pipe end, and the branch passage end opening surface 4d of the high pressure side return passage 4 and the low pressure side return passage 5 are divided.
The branch passage end opening surface 5d is arranged in a state of being close to and concentric with the branch pipe axis. Other configurations are similar to those of the first embodiment.

[Third Embodiment] FIG. 5 shows the road end opening surface 4b of the high pressure side return passage 4 on the upper side, and the road end opening surface 5b of the low pressure side return passage 5 in the upper side.
In the present embodiment, the refrigerant in the wet vapor state returned from the high pressure side return passage 4 is blown into the intercooler 3 from the upper side to the lower side. Since it is easy, the liquid component having a large inertial force in the wet vapor state refrigerant easily drops toward the bottom of the intercooler 3, and the liquid component from the wet vapor state refrigerant is easily separated to the intercooler bottom part. effective. Other configurations are similar to those of the first embodiment.

Other Embodiments 1. The multi-stage heat pump device according to the present invention is not limited to air-conditioning applications such as cooling and heating, and can be applied to various applications in various fields dealing with cold heat and hot heat, even if it is a multi-stage heat pump device with three or more stages. good. 2. Even if each of the road end of the high-pressure side return passage and the road end of the low-pressure side return passage is formed in a cylindrical shape with a substantially constant diameter, and the road end opening surfaces are opposed to each other in a close state. good. 3. The road end opening surface of the high-pressure side return passage and the road end opening surface of the low-pressure side return passage may be opposed to each other in the horizontal direction in a close state. 4. The opening area of the road end opening surface of the high pressure side return passage may be different from the opening area of the road end opening surface of the low pressure side return passage.

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 configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a partially cutaway enlarged side view of a main part.

FIG. 2 is a refrigerant circuit diagram showing a refrigerant circulation system in a cooling mode.

FIG. 3 is a refrigerant circuit diagram showing a refrigerant circulation system in a heating mode.

FIG. 4 is an enlarged cross-sectional view of a main part showing a second embodiment.

FIG. 5 is an enlarged cross-sectional view of a main part showing a third embodiment.

FIG. 6 is an enlarged sectional view of a main part showing a conventional example.

[Explanation of symbols]

 3 Intercooler 4 High pressure side return path 4a Road end 4b Road end opening surface 5 Low pressure side return path 5a Road end 5b Road end opening surface ex1 High pressure side expansion means (low pressure side expansion means) ex2 High pressure side expansion means (low pressure) Side expansion means) C condenser CmH high pressure side compressor CmL low pressure side compressor E evaporator GA internal gas phase region

Claims (4)

[Claims] 1. A refrigerant taken out in a vapor phase from an intercooler (3) is passed through a high pressure side compressor (CmH), a condenser (C), and a high pressure side expansion means (ex1 or ex2) in this order,
A high pressure side circulation system which returns to the intermediate cooler (3) in a wet vapor state, and a low pressure side expansion means (ex2 or ex1) / evaporator (E) for the refrigerant taken out in a liquid phase state from the intermediate cooler (3). A multi-stage heat pump device including a low-pressure side circulation system that passes through a low-pressure side compressor (CmL) in order and returns to the intercooler (3) in a superheated gas phase state, wherein the refrigerant is in a wet vapor state and The road end opening surface (4b) of the high pressure side return path (4) returning from the high pressure side expansion means (ex1 or ex2) to the intercooler (3) and the low pressure side compressor (CmL) in a superheated vapor phase state of the refrigerant. ) To the intercooler (3)
A multi-stage heat pump device in which the low-pressure side return path (5) to be returned to the front end is opposed to the road end opening surface (5b) in close proximity in the internal gas phase region (GA) of the intercooler (3). 2. A road end portion (4a) of the high pressure side return path (4).
And the road end portion (5a) of the low pressure side return passage (5) are formed in a hood shape in which the diameter is increased toward the road end opening surface side, and the expanded road end opening surfaces (4b, 5b) are connected to each other. The multi-stage heat pump device according to claim 1, which are closely opposed to each other. 3. A road end opening surface (4) of the high pressure side return path (4).
b) and the road end opening surface (5b) of the low-pressure side return path (5) are each divided into a plurality of parts, which are dispersed in the internal gas phase region (GA) of the intercooler (3). The multi-stage heat pump device according to claim 1. 4. A road end opening surface (4) of the high pressure side return path (4).
b) and the road end opening surface (5b) of the low pressure side return path (5) are opposed to each other in the longitudinal axis direction of the vertically elongated intercooler (3). The described multi-stage heat pump device.