JPH04263747A - Refrigerator cycle device - Google Patents

Abstract

PURPOSE:To obtain higher temperature by a condenser and lower temperature by a vaporizer with an operation of high efficiency by a method wherein high boiling point, refrigerant at a high stage and low boiling point refrigerant at a low stage are separated without using a heat exchanger in the middle part of a multiple refrigeration cycle device, and suction and discharge temperatures of a compressor at the high stage are lowered so that two compressors are operated at a low compression ratio. CONSTITUTION:A first compressor 1, a second compressor 3, a condenser 4, a first pressure reducer 5, a rectifying separator 6, a second pressure reducer 8 connected to a top part of the rectifying separator 6 and a vaporizor 9 are connected in succession, and a discharge pipe 2 of the compressor 1 is bypassed and connected to the top part of the rectifying separator 6. A bottom part of the rectifying separator 6 is connected to the second compressor 3 in the rear-stream of a discharge bypass pipe 10, whereby a non-azeotrope refrigerant which comprises of a low boiling point refrigerant and a high boiling point refrigerant is sealed in.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to refrigeration cycle devices for obtaining higher or lower temperatures, such as air conditioning, hot water supply, or ultra-low temperature devices.

0002

2. Description of the Related Art In recent years, refrigeration cycle devices have been required to be able to operate at higher temperatures or lower temperatures.

[0003] Conventionally, this type of refrigeration cycle device
A multi-component refrigeration cycle device in which a plurality of refrigeration cycle devices are connected in a cascade manner is known. In this multicomponent refrigeration cycle device, a refrigerant component with a high boiling point (hereinafter referred to as a high-boiling point refrigerant) is usually sealed in a high-stage refrigeration cycle, and a refrigerant component with a low boiling point (hereinafter referred to as a low-boiling point refrigerant) is enclosed in a low-stage refrigeration cycle. It was configured to include an intermediate heat exchanger that exchanges heat between the evaporative refrigerant in the higher stage and the condensed refrigerant in the lower stage.

[0004] In such a refrigeration cycle device, since a high boiling point refrigerant is sealed in the high stage refrigeration cycle, a high temperature can be obtained while lowering the vapor pressure in the high stage condenser. Since the cycle is filled with a low boiling point refrigerant, low temperatures can be obtained without creating negative pressure in the low stage evaporator.

[0005]

[Problems to be Solved by the Invention] Such conventional refrigeration cycle devices are suitable for the purpose of obtaining higher or lower temperatures, but the high boiling point refrigerant sealed in the high stage refrigeration cycle and the low stage refrigerant In order to separate the low boiling point refrigerant sealed in the refrigeration cycle, heat exchange is performed between the evaporating refrigerant in the high stage and the condensing refrigerant in the low stage, and as a result, the evaporation temperature in the high stage is lower than the condensing temperature in the lower stage. The compressors disposed in each of the high-stage and low-stage refrigeration cycles are operated at high compression ratios, resulting in a problem of poor efficiency.

[0006]Furthermore, recent usage patterns of refrigeration cycle equipment include not only single-function usage such as high-temperature hot water supply equipment and ultra-low temperature equipment, but also multi-purpose usage such as dual use of high-temperature hot water supply and cooling/heating. There is. At this time, in multi-component refrigeration cycle equipment, it is possible to perform both hot water supply and heating functions in the high-stage condenser, but the high boiling point refrigerant has a low heating capacity, so the equipment must be large-scale. I had a problem.

The present invention solves the above-mentioned problems by separating the high-boiling point refrigerant in the upper stage and the low-boiling point refrigerant in the lower stage without using a heat exchanger in the intermediate section, and by separating the high-stage high-boiling point refrigerant and the low-boiling point refrigerant in the lower stage, thereby reducing the suction and discharge of the high-stage compressor. The first objective is to be able to operate the two compressors at a low compression ratio while lowering the temperature, and with high efficiency operation, it is possible to obtain a higher temperature in the condenser and a lower temperature in the evaporator. The purpose is to

[0008] A second objective is to mix the high-boiling point refrigerant in the high stage and the low-boiling point refrigerant in the low stage, and to be able to control the composition of the refrigerant so as to increase the heating capacity in the high stage condenser.
The purpose is to

[0009]

[Means for Solving the Problems] In order to achieve the above first object, the present invention provides a first compressor, a second compressor, a condenser,
A first pressure reducing device, a rectifying separator, a second pressure reducing device connected to the top of the rectifying separator, an evaporator, etc. are connected in order, and the discharge pipe of the first compressor is bypassed to connect the top of the rectifying separator. , the bottom of the rectification separator is connected to the second compressor on the downstream side of the discharge bypass pipe of the first compressor, and a non-azeotropic mixed refrigerant consisting of a low boiling point refrigerant and a high boiling point refrigerant is supplied. Enclosing it is the first means of solving the problem.

[0010] In addition, in order to achieve the second object, a circuit that bypasses the discharge pipe of the first compressor of the first problem solving means and is connected to the top of the rectification separator; The second problem-solving means is that a solenoid valve is provided in a circuit connected from the bottom to the second compressor on the downstream side of the discharge bypass pipe of the first compressor.

[0011]

According to the present invention, the non-azeotropic mixed refrigerant is separated inside the rectification separator, the low-boiling refrigerant is concentrated at the top, and the high-boiling refrigerant is concentrated at the bottom. Therefore, the second
Concentrated low-boiling refrigerant is circulated through a first refrigeration cycle connected to the top of the rectification separator by bypassing the pressure reducing device, the evaporator, the first compressor, and the discharge pipe of the first compressor. In addition, since the bottom of the rectification separator where the high boiling point refrigerant is concentrated is connected to the second compressor on the downstream side of the discharge bypass pipe of the first compressor, the flow from the connected first compressor is A second refrigeration cycle is mixed with a low boiling point refrigerant to lower the suction temperature of the second compressor, and is connected to the second compressor, condenser, first pressure reducing device, and rectification separator. A non-azeotropic mixed refrigerant with a mixed composition containing more high boiling point components than in the refrigeration cycle is circulated. The non-azeotropic mixed refrigerant having the composition thus mixed undergoes separation again inside the rectification separator, with the low boiling point refrigerant being concentrated at the top and the high boiling point refrigerant being concentrated at the bottom.

[0012] Therefore, unlike the conventional multicomponent refrigeration cycle equipment, there is no need for an intermediate heat exchanger, and the first heat exchanger is not required.
The refrigerant can be separated into a low boiling point refrigerant in the second refrigeration cycle and a high boiling point refrigerant in the second refrigeration cycle, and the two compressors can be operated at a low compression ratio while lowering the suction and discharge temperatures of the second compressor. With highly efficient operation, it is possible to obtain higher temperatures in the condenser and lower temperatures in the evaporator, and the refrigerant components and vapor pressure after such separation are lower than those of the non-azeotropic mixture initially sealed. It can be arbitrarily selected depending on the combination and composition of refrigerants, the pressure settings of each pressure reducing device, etc.

The second problem-solving means also provides a circuit that bypasses the discharge pipe of the first compressor and is connected to the top of the rectification separator, and a circuit that bypasses the discharge pipe of the first compressor and connects the discharge bypass pipe of the first compressor from the bottom of the rectification separator. If the circuit connected to the second compressor is closed on the downstream side, separation inside the rectification separator is also stopped, and the non-azeotropic mixed refrigerant of the enclosed composition is transferred to the first compressor, It circulates through the second compressor, condenser, first pressure reduction device, rectification separator, second pressure reduction device connected to the top of the rectification separator, and evaporator, and non-azeotropic with more low-boiling components than during separation. The mixed refrigerant is condensed in the condenser to increase the heating capacity, and it is also possible to control the composition of the refrigerant.

[0014]

[Embodiment] An embodiment of the present invention will be described below with reference to FIG.

As shown in the figure, the first compressor 1 has a discharge pipe 2
is connected to the second compressor 3, the condenser 4 and the first pressure reducing device 5 are connected to the second compressor 3, and the outlet pipe of the first pressure reducing device 5 is connected to the middle part of the rectification separator 6. . The cooler 7 is used to help condense the refrigerant discharged from the top of the rectification separator 6, and a second pressure reducing device 8 is connected to the top of the rectification separator 6. The outlet pipe of the evaporator 9 is connected to the first compressor 1, and the cold heat source of the cooler 7 is constituted by the outlet pipe of the evaporator 9. Further, a discharge bypass pipe 10 that bypasses the discharge pipe 2 of the first compressor 1 is connected to the top of the rectification separator 6, and the bottom of the rectification separator 6 is connected to the first compressor 1 through a pipe 11.
is connected to the discharge pipe 2 of the first compressor 1 at a position on the downstream side of the discharge bypass pipe 10, and as a result, the second compressor 3
It will also be connected. Further, a reservoir 12 is provided at the bottom of the rectifying separator 6, and the discharge bypass pipe 10 of the first compressor 1 is connected to the rectifying separator 6 via a heat exchanger 13 provided inside the reservoir 12. It is configured to be connected to the top. Further, a solenoid valve 1 is provided in the discharge bypass pipe 10 of the first compressor 1 and the pipe 11 from the bottom of the rectification separator 6, respectively.
4 and 15 are provided. The refrigeration cycle device is sealed with a non-azeotropic mixed refrigerant consisting of a low boiling point refrigerant and a high boiling point refrigerant.

To explain the operation in the above configuration, inside the rectification separator 6, the two-phase refrigerant supplied from the outlet pipe of the first pressure reducing device 5 and the discharge bypass pipe 10 of the first compressor 1 are mixed.
The gas refrigerant supplied from the reservoir 12 is liquefied via the heat exchanger 13 provided inside the reservoir 12 and the liquid refrigerant is supplied to the top of the rectification separator 6, and the discharge bypass pipe 10 of the first compressor 1.
A reservoir 12 provided at the bottom of the rectification separator 6 is heated and vaporized through a heat exchanger 13 by the gas refrigerant supplied from the
The gas refrigerant inside causes the separation of the non-azeotropic refrigerant mixture by a rectification effect, concentrating the low-boiling refrigerant at the top and the high-boiling refrigerant at the bottom. Therefore, a cooler 7 for assisting condensation of the refrigerant drawn out from the top of the rectification separator 6, and a second pressure reducing device 8 connected to the top of the rectification separator 6.
, an evaporator 9, a first compressor 1, and a discharge bypass pipe 10 of the first compressor 1 connected to the top of the rectification separator 6. is circulated. In addition, a reservoir 12 in which the high boiling point refrigerant is concentrated and is provided at the bottom of the rectification separator 6 is located downstream of the discharge bypass pipe 10 of the first compressor 1 and is connected to the discharge pipe 2 of the first compressor 1. Since the high boiling point liquid refrigerant is mixed with the low boiling point gas refrigerant from the connected first compressor 1, the suction temperature of the second compressor 3 is lowered, and the second compressor 3. The second refrigeration cycle, which is composed of a condenser 4, a first pressure reduction device 5, and a rectification separator 6, contains a non-azeotropic mixture with a mixed composition containing more high-boiling components than the first refrigeration cycle. Refrigerant circulates. The non-azeotropic mixed refrigerant having the composition thus mixed undergoes separation again inside the rectification separator 6, with the low boiling point refrigerant being concentrated at the top and the high boiling point refrigerant being concentrated at the bottom.

[0017] Therefore, unlike the conventional multicomponent refrigeration cycle equipment, there is no need for an intermediate heat exchanger, and the first heat exchanger is not required.
Not only can the refrigerant be separated into a low boiling point refrigerant in the second refrigeration cycle and a non-azeotropic mixed refrigerant having a composition containing more high boiling point components than in the first refrigeration cycle, but also
While reducing the suction and discharge temperatures of the second compressor 3,
The discharge pressure of the first compressor 1 and the suction pressure of the second compressor 3 are almost the same, and the first compressor 1 and the second compressor 3 are each operated with a small compression ratio, resulting in high efficiency. In addition, high temperatures can be obtained while lowering the vapor pressure in the condenser 4 in the second refrigeration cycle, and low temperatures can be achieved without creating a negative pressure in the evaporator 9 in the first refrigeration cycle. Obtainable. Note that the refrigerant components and vapor pressure after such separation depend on the combination and composition of the non-azeotropic mixed refrigerant initially sealed, as well as the first pressure reducing device 5 and the second pressure reducing device.
It can be arbitrarily selected by setting the pressure by the pressure reducing device 8, etc., and the operating pressure for separation of the rectification separator 6 is
This is possible by configuring the entire refrigeration cycle as described above so that the pressure level is approximately the same as the discharge pressure of the first compressor 1 and the suction pressure of the second compressor 3.

Further, a solenoid valve 14 provided in the discharge bypass pipe 10 of the first compressor 1 connected to the top of the rectification separator 6
Also, if the solenoid valve 15 installed in the pipe 11 from the bottom of the rectification separator 6 is closed, separation inside the rectification separator 6 is also stopped, so that the non-azeotropic mixture of the enclosed composition The refrigerant is supplied to the first compressor 1, the discharge pipe 2, the second compressor 3, the condenser 4, and the first
circulates through a pressure reduction device 5, a rectification separator 6, a cooler 7, a second pressure reduction device 8 connected to the top of the rectification separator 6, and an evaporator 9;
The non-azeotropic mixed refrigerant containing more low boiling point components than when separated is condensed in the condenser 4, and the heating capacity can be increased.
It also becomes possible to control the composition of the refrigerant.

In the above embodiment, the outlet pipe of the first pressure reducing device 5 is connected to the middle part of the rectifying separator 6, but the connection position of the rectifying separator 6 and the outlet pipe of the first pressure reducing device 5 may be between the top and bottom of the rectification separator 6, and it is also possible to make the throttle opening of the first pressure reducing device 5 and the second pressure reducing device 8 variable, so that the cold source of the cooler 7 The heating source for the heat exchanger 13 may be any other means as long as it is an additional means for promoting separation by the two-phase refrigerant supplied from the first pressure reducing device 5. Although the present invention has been described as an example of a basic refrigeration cycle device, it goes without saying that it may be applied to air conditioning, hot water supply, ultra-low temperature devices, and the like.

[0020]

As is clear from the above embodiments, according to the present invention, the first compressor, the second compressor, the condenser, the first pressure reducing device, the rectification separator, and the connection to the top of the rectification separator are provided. A second pressure reducing device, an evaporator, etc. are connected in order, and the discharge pipe of the first compressor is bypassed and connected to the top of the rectification separator, and the bottom of the rectification separator is connected to the bottom of the first compressor. Since it is connected to the second compressor on the downstream side of the discharge bypass pipe and contains a non-azeotropic mixed refrigerant consisting of a low boiling point refrigerant and a high boiling point refrigerant, the non-azeotropic mixed refrigerant is mixed inside the rectification separator. Separation occurs, concentrating the low-boiling refrigerant at the top and concentrating the high-boiling refrigerant at the bottom, with the concentrated low-boiling refrigerant circulating in the evaporator and the high-boiling refrigerant circulating in the condenser, which is different from the traditional multi-component system. It does not require a heat exchanger in the middle like a refrigeration cycle device, and lowers the suction and discharge temperatures of the second compressor to achieve higher temperatures in the condenser and lower temperatures in the evaporator with highly efficient operation. Can be done.

[0021] Also, a circuit is connected to the top of the rectification separator by bypassing the discharge pipe of the first compressor, and a second circuit is connected from the bottom of the rectification separator to the downstream side of the discharge bypass pipe of the first compressor. Since a solenoid valve is provided in the circuit connected to the compressor, this solenoid valve can be used to bypass the discharge pipe of the first compressor and connect the circuit to the top of the rectification separator, or to connect the circuit from the bottom of the rectification separator to the first compressor. By closing the circuit connected to the second compressor on the downstream side of the discharge bypass pipe of the machine, separation inside the rectification separator is stopped, and the non-azeotropic mixed refrigerant with the enclosed composition is A component with a lower boiling point than that at the time of separation is circulated through the first compressor, the second compressor, the condenser, the first pressure reducing device, the rectification separator, the second pressure reduction device connected to the top of the rectification separator, and the evaporator. A non-azeotropic refrigerant mixture with a large amount of refrigerant is condensed in the condenser, increasing the heating capacity, and furthermore, it becomes possible to control the composition of such a refrigerant.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a refrigeration cycle device according to an embodiment of the present invention.

[Explanation of symbols]

1 First compressor 2 Discharge pipe 3 Second compressor 4 Condenser 5 First pressure reducing device 6 Rectification separator 8 Second pressure reducing device 9 Evaporator 10 Discharge bypass pipe

Claims (2)

[Claims] Claim 1: A first compressor, a second compressor, a condenser, a first pressure reduction device, a rectification separator, a second pressure reduction device connected to the top of the rectification separator, an evaporator, etc. are connected in order, The discharge pipe of the first compressor is bypassed and connected to the top of the rectification separator, and the bottom of the rectification separator is connected to the second compressor on a downstream side of the discharge bypass pipe of the first compressor. A refrigeration cycle device that is connected to a refrigeration cycle and sealed with a non-azeotropic mixed refrigerant consisting of a low-boiling point refrigerant and a high-boiling point refrigerant. Claim 2: A circuit connected to the top of the rectification separator by bypassing the discharge pipe of the first compressor, and a second circuit connected from the bottom of the rectification separator to the downstream side of the discharge bypass pipe of the first compressor. The refrigeration cycle device according to claim 1, further comprising a solenoid valve provided in the circuit connected to the compressor.