JP5419901B2 - Refrigeration cycle apparatus, flow path switching apparatus, and flow path switching method - Google Patents

Description

  The present invention relates to a refrigeration cycle apparatus that includes a plurality of evaporators having different evaporation temperatures, and that recovers and uses expansion power by using an ejector.

  The conventional refrigeration cycle apparatus includes a pressure raising device 15 that pressurizes the refrigerant from the evaporator 11 set to a low pressure with the refrigerant flowing from the evaporator 13 set to a high pressure (for example, Patent Document 1). ). Thereby, compared with the refrigerating cycle which does not use the pressure raising apparatus 15, the suction pressure of a compressor rises. Thereby, the power consumption of the compressor is reduced, and energy saving of the refrigeration cycle can be achieved (Patent Document 1).

JP 2009-236330 A

  However, in Patent Document 1, when the pressure levels of the evaporator 13 set at a high pressure and the evaporator 11 set at a low pressure are reversed, the refrigerant inflow path to the ejector (pressure riser 15) is reversed. However, there is a problem that the effect of increasing the pressure cannot be obtained.

  An object of the present invention is to constantly improve the operation efficiency by using an ejector in a refrigeration cycle composed of a plurality of evaporators having different evaporation temperatures.

The refrigeration cycle apparatus of the present invention is
A driving refrigerant inlet into which the driving refrigerant flows, a suction refrigerant inlet into which the suction refrigerant sucked by the driving refrigerant flows, and a mixed refrigerant outlet from which the mixed refrigerant mixed with the driving refrigerant and the suction refrigerant flows out And an ejector in which the mixed refrigerant outlet is connected to the suction side of the compressor,
A first refrigerant inlet through which refrigerant A flows; a second refrigerant inlet through which refrigerant B flows; a first refrigerant outlet connected to the drive refrigerant inlet of the ejector; and the suction refrigerant inlet of the ejector. The refrigerant B flowing in from the first refrigerant outlet and flowing in the refrigerant B from the second refrigerant inlet Out of the second refrigerant outlet, and the refrigerant A flowing in from the first refrigerant inlet flows out of the second refrigerant outlet and flows in from the second refrigerant inlet. A flow path switching device for switching between the second flow path for allowing the refrigerant B to flow out of the first refrigerant outlet,
A compressor having a suction side connected to the mixed refrigerant outlet of the ejector;
A radiator connected by piping to the discharge side of the compressor;
A first pressure reducing mechanism connected by piping to the refrigerant outflow side of the radiator;
One side is connected to the first pressure reducing mechanism by piping, the other side is connected to the first refrigerant inflow port of the flow path switching device, and the refrigerant A flows into the flow path switching device from the other side. The first evaporator;
A second pressure reducing mechanism connected to a pipe branched from the middle of the pipe connecting the first pressure reducing mechanism and the radiator;
One side is connected to the second pressure reducing mechanism by piping, the other side is connected to the second refrigerant inlet of the flow path switching device, and the refrigerant B flows into the flow path switching device from the other side. And a second evaporator.

  The refrigeration cycle apparatus of the present invention uses the pressure energy of the refrigerant flowing out of the high temperature side evaporator as a drive medium of the ejector, and sucks and pressurizes the refrigerant flowing out of the low temperature side evaporator to suck the pressure of the compressor To raise. As a result, since the power consumption of the compressor can be reduced, energy saving of the refrigeration cycle can be achieved.

FIG. 2 is a schematic diagram showing a configuration of a refrigeration cycle apparatus 1010 according to Embodiment 1. FIG. 3 is a schematic diagram illustrating a configuration of a flow path control device 1081 according to the first embodiment. The figure which shows the inside of the ejector 105 of Embodiment 1, and an internal pressure distribution. FIG. 3 is a Mollier diagram of the refrigeration cycle apparatus 1010 according to the first embodiment. 6 is a flowchart showing the operation of the flow path control device 1081 of the first embodiment. FIG. 5 is a diagram showing a refrigerant flow path of the flow path control device 1081 of the first embodiment. The Mollier diagram which shows the effect of Embodiment 1. FIG. The figure which shows the relationship between the ejector efficiency and pressure | voltage rise amount of Embodiment 1. FIG. The figure which shows the relationship between the ejector efficiency of Embodiment 1, and COP. FIG. 6 is a schematic diagram illustrating a configuration of a flow path control device 1082 according to the second embodiment. The figure which shows the flow path of the refrigerant | coolant of the flow-path control apparatus 1082 of Embodiment 2. FIG. FIG. 9 is a schematic diagram showing a configuration of a refrigeration cycle apparatus 1010 according to Embodiment 3.

Embodiment 1 FIG.
FIG. 1 is a schematic diagram showing a refrigeration cycle apparatus 1010 in the first embodiment. In the refrigeration cycle apparatus 1010, a compressor 101, a condenser 102 that is a radiator, a first flow control valve 103 (first decompression mechanism), and a first evaporator 104 are sequentially connected by a refrigerant pipe. Further, the second flow control valve 106 and the second evaporator 107 branch from the outlet of the condenser 102 and are sequentially connected by refrigerant piping. The first evaporator 104 and the second evaporator 107 are connected to a flow path control device 1081 (flow path switching device). The flow path control device 1081 is connected to the suction refrigerant inlet 1052 of the ejector 105 and the driving refrigerant inlet 1051 of the ejector 105 through refrigerant pipes, respectively. The mixed refrigerant outlet 1053 of the ejector 105 is connected to the compressor by a refrigerant pipe. The first evaporator 104 is installed in the first cold chamber 001, and the second evaporator 107 is installed in the second cold chamber 002.

The configuration of FIG. 1 will be described in more detail.
(1) Ejector 105
The ejector 105 includes a driving refrigerant inlet 1051 into which the driving refrigerant flows, a suction refrigerant inlet 1052 into which the suction refrigerant sucked in by the driving refrigerant flows, and a mixed refrigerant in which the mixed refrigerant of the driving refrigerant and the suction refrigerant flows out. And a refrigerant outlet 1053. The mixed refrigerant outlet 1053 is connected to the suction side of the compressor 101.

(2) Flow path control device 1081
The flow path control device 1081 is connected to the first refrigerant inlet 81 through which the refrigerant A flows, the second refrigerant inlet 82 through which the refrigerant B flows, and the driving refrigerant inlet 1051 of the ejector 105. And a second refrigerant outlet 92 connected to the suction refrigerant inlet 1052 of the ejector 105. The flow path control device 1081 causes the refrigerant A flowing in from the first refrigerant inlet 81 to flow out from the first refrigerant outlet 91 and the refrigerant B flowing in from the second refrigerant inlet 82 from the second refrigerant outlet 92. A first flow path (flow path 71 indicated by a broken line) to be flown out and a refrigerant A that has flowed in from the first refrigerant flow inlet 81 flows out from the second refrigerant flow outlet 92 and flows in from the second refrigerant flow inlet 82 The second flow path (flow path 72 shown by a solid line) through which B flows out from the first refrigerant outlet 91 is switched.

(3) Connection relationship of other components constituting the refrigeration cycle The compressor 101 has a suction side connected to the mixed refrigerant outlet 1053 of the ejector 105.
The condenser 102 is connected to the discharge side of the compressor 101 by piping. The first flow control valve 103 (first pressure reducing mechanism) is connected to the refrigerant outflow side of the condenser 102 by a pipe. The first evaporator 104 (the first evaporator) has one side (refrigerant inflow side) connected to the first flow control valve 103 with a pipe, and the other side (refrigerant outflow side) of the flow path control device 1081. The refrigerant A is connected to the first refrigerant inflow port 81 and flows in the refrigerant A into the flow path control device 1081 from the other side. The second flow control valve 106 (second pressure reducing mechanism) is connected to a pipe branched from the middle of the pipe connecting the first flow control valve 103 and the condenser 102. As for the 2nd evaporator 107 (2nd evaporator), one side (refrigerant inflow side) is connected with the 2nd flow control valve 106 by piping, and the other side (refrigerant outflow side) is the 1st of channel control device 1081. 2 Refrigerant B is connected to the refrigerant inlet 82, and the refrigerant B flows into the flow path control device 1081 from the other side.

  FIG. 2 is a diagram illustrating an internal configuration of the flow path control device 1081. The configuration of the flow path control device 1081 will be described with reference to FIG. The flow path control device 1081 includes a flow path control valve 601a (first flow path switching valve), a flow path control valve 601b (third flow path switching valve), a flow path control valve 601c (second flow path switching valve), a flow A path control valve 601d (fourth flow path switching valve), a pressure detector 602a (an example of a first detector), a pressure detector 602b (an example of a second detector), a control unit 603, and the like are provided. The control unit 603 includes a reception unit 604, a calculation unit 605, and a transmission unit 606. The control unit 603 controls the flow path control valve 601a to the flow path control valve 601d based on the pressure detection results (detected values) of the pressure detector 602a and the pressure detector 602b. As shown in FIG. 2, the first refrigerant inlet 81, the flow path control valve 601 a, and the suction refrigerant inlet 1052 of the ejector 105 are sequentially connected by piping. Further, the second refrigerant inlet 82, the flow path control valve 601c, and the driving refrigerant inlet 1051 of the ejector 105 are sequentially connected by piping. Further, in the middle of the pipe connecting from the middle (Y1) between the first refrigerant inlet 81 and the flow path control valve 601a to the middle (Z2) between the flow path control valve 601c and the driving refrigerant inlet 1051, the flow path control valve 601b is arranged. Further, in the middle of the pipe connecting from the middle (Y2) between the second refrigerant inlet 82 and the flow path control valve 601c to the middle (Z1) between the flow path control valve 601a and the suction refrigerant inlet 1052, the flow path control valve 601d is arranged.

  As described above, in FIG. 2, the first evaporator 104 installed in the first cold storage chamber 001 includes the branch portion Y1, the flow path control valve 601a, the merge point Z1, and the suction refrigerant flow of the ejector 105 in the flow path control device 1081. The inlet 1052 is sequentially connected by a refrigerant pipe. Further, the branch portion Y1, the flow path control valve 601b, the junction Z2, and the drive refrigerant inlet 1051 of the ejector 105 are sequentially connected by refrigerant piping.

  On the other hand, the second evaporator 107 provided in the second cold storage chamber 002 is sequentially connected to the branch portion Y2, the flow path control valve 601c, the junction Z2, and the drive refrigerant inlet 1051 of the ejector 105. Further, the branch portion Y2, the flow path control valve 601d, the junction point Z1, and the suction refrigerant inlet 1052 of the ejector 105 are sequentially connected by a refrigerant pipe.

(Control by control unit 603)
A pressure detector 602a is installed on the upstream side of the branch part Y1, and a pressure detector 602b is installed on the upstream side of the branch part Y2, and detects the refrigerant pressure. The detection signals of the pressure detectors 602a and 602b are collected in the receiving unit 604 in the control unit 603. The arithmetic unit 605 performs a comparison determination based on the detection signal received by the receiving unit 604, various set values, and the like, and transmits a control signal to each of the flow path control valves 601a to 601d via the transmitting unit 606.

  FIG. 3 shows the configuration of the ejector 105 and the internal pressure distribution. The ejector 105 includes a nozzle unit 201, a mixing unit 202, and a diffuser unit 203. The nozzle part 201 further includes a pressure reducing part 201a, a nozzle throat part 201b, and a divergent part 201c. Alphabets such as “e, g, h, i, j” in FIG. 3 represent each point of the Mollier diagram described later.

  The high-pressure refrigerant (driving refrigerant) that has flowed out of the flow path control device 1081 flows from the driving refrigerant inlet 1051 and expands under reduced pressure as the flow path area decreases in the pressure reducing section 201a. The speed increases due to the decompression, and the sound speed is reached at the nozzle throat 201b. The driving refrigerant that has reached the speed of sound is depressurized while further increasing its speed at the divergent portion 201c. As a result, a super-high-speed gas-liquid two-phase refrigerant flows out from the nozzle part 201. On the other hand, the refrigerant sucked from the suction refrigerant inlet 1052 of the ejector 105 is drawn into the ultrahigh-speed refrigerant (suction refrigerant) due to the pressure difference between the suction refrigerant inlet 1052 and the outlet of the nozzle unit 201. From the outlet of the nozzle unit 201, that is, the inlet of the mixing unit 202, the ultra-high speed driving refrigerant and the low-speed suction refrigerant start to be mixed (mixed refrigerant). In the mixed refrigerant, the pressure is recovered (increased) by exchanging momentum between the driving refrigerant and the suction refrigerant. Further, also in the diffuser unit 203, the dynamic pressure is converted into a static pressure by the deceleration due to the expansion of the flow path, the pressure is increased, and the mixed refrigerant flows out from the diffuser unit 203 (mixed refrigerant outlet 1053).

(Refrigeration cycle operation)
Next, the operation of the refrigeration cycle apparatus 1010 will be described by taking as an example a case where the refrigerant pressure of the first evaporator 104 is lower than the refrigerant pressure of the second evaporator 107.
FIG. 4 is a Mollier diagram in the case of the refrigerant pressure of the first evaporator 104 <the refrigerant pressure of the second evaporator 107. The horizontal axis of the Mollier diagram in FIG. 4 indicates the specific enthalpy of the refrigerant, and the vertical axis indicates the pressure. Further, points a to j in the Mollier diagram indicate refrigerant states at the positions shown in FIGS. 1 and 2.

  The low-pressure refrigerant in the state a at the suction port of the compressor 101 becomes a high-temperature and high-pressure refrigerant (state b) by the compressor 101 and flows into the condenser 102. The refrigerant in the state c cooled by heat exchange with the outdoor air by the condenser 102 is converted into a refrigerant Wr1 (refrigerant A) flowing to the first evaporator 104 and a refrigerant Wr2 (refrigerant B) flowing to the second evaporator 107. Divide. The refrigerant Wr1 is decompressed by the first flow control valve 103 to be in the state d and flows into the first evaporator 104. The refrigerant Wr1 is heated by the air in the first cold storage chamber 001 in the first evaporator 104 to be in the state e, and is guided to the suction refrigerant inlet 1052 of the ejector 105 by the flow path control device 1081. On the other hand, the refrigerant Wr2 branched at the outlet of the condenser 102 is decompressed by the second flow rate control valve 106 to be in the state f and flows into the second evaporator 107. The second evaporator 107 is heated by the air in the second cold storage chamber 002 to be in the state g, and is guided to the drive refrigerant inlet 1051 of the ejector 105 by the flow path control device 1081.

  The refrigerant Wr2 in the state g flowing into the driving refrigerant inlet 1051 of the ejector 105 is decompressed by the nozzle portion 201 of the ejector and becomes extremely high speed. The refrigerant Wr2 in the state h that has reached an ultra-high speed is mixed with the suction refrigerant, that is, the refrigerant Wr1 in the state e that has flowed out of the first evaporator 104, immediately after the outlet of the nozzle unit 201, and enters the state i. The refrigerant Wr1 and the refrigerant Wr2 are mixed in the mixing unit 202 of the ejector 105, and the mixed refrigerant is increased in pressure in the diffuser unit 203 to a state j, flows out of the mixed refrigerant outlet 1053 of the ejector 105, and is compressed. 101 is aspirated. A refrigeration cycle is formed by the above operation.

(Operation of the flow path control device 1081)
FIG. 5 is a flowchart showing the operation of the flow path control device 1081. Next, the operation of the flow path control device 1081 will be described with reference to FIG.
(1) In ST101, the refrigerant pressure is detected and collected in the receiving unit 604.
(2) In ST102, the calculation unit 605 compares the detected pressure value. When the detection value of the pressure detector 602a is smaller than the pressure detector 602b, the calculation unit 605
That is,
In the case of the refrigerant Wr1 pressure of the first evaporator 104 <the refrigerant Wr2 pressure of the second evaporator 107 (in the case of the example described in FIG. 4), the control unit 603 sets the flow path control valves 601a and 601c in ST103-a. Open and close the flow path control valves 601b and 602d (second flow path shown in FIG. 1). In this case, the high-pressure refrigerant Wr2 flowing out of the second evaporator 107 flows into the driving refrigerant inlet 1051, and the low-pressure refrigerant Wr1 flowing out of the first evaporator 104 flows into the suction refrigerant inlet 1052.
(3) On the other hand, when the detection value of the pressure detector 602a is larger than the detection value of the pressure detector 602b,
That is,
Refrigerant Wr1 pressure of first evaporator 104> Refrigerant Wr2 of second evaporator 107
In this case, the control unit 603 opens the flow path control valves 601b and 601d and closes the flow path control valves 601a and 602c in ST103-b (first flow path shown in FIG. 1). In this case, the high-pressure refrigerant Wr1 flowing out of the first evaporator 104 flows into the driving refrigerant inlet 1051, and the low-pressure refrigerant Wr2 flowing out of the second evaporator 107 flows into the suction refrigerant inlet 1052.
(4) Thus, of the refrigerants Wr1 and Wr2 flowing into the flow path control device 1081, the higher pressure flows into the driving refrigerant inlet 1051, and the lower pressure flows into the suction refrigerant inlet 1052.

  FIG. 6 shows the flow of the refrigerant described in FIG. The second flow path 72 (solid line) indicates the flow of the refrigerant when the detected value (refrigerant Wr1) of the pressure detector 602a is lower than the detected value (refrigerant Wr2) of the pressure detector 602b. The refrigerant Wr1 flowing out from the first evaporator 104 in the first cold storage chamber 001 flows to the suction refrigerant inlet 1052 of the ejector 105 through the branch portion Y1 and the flow path control valve 601a. The refrigerant Wr2 that has flowed out of the second evaporator 107 of the second cold storage chamber 002 flows to the drive refrigerant inlet 1051 of the ejector 105 through the branch portion Y2 and the flow path control valve 601c.

  The first flow path 71 (broken line) indicates the flow of the refrigerant when the detected value of the pressure detector 602a (refrigerant Wr1) is higher than the detected value of the pressure detector 602b (refrigerant Wr2). In this case, the refrigerant Wr1 flowing out from the first evaporator 104 flows to the drive refrigerant inlet 1051 of the ejector 105 through the flow path control valve 601b, and the refrigerant Wr2 flowing out from the second evaporator 107 is changed to the flow path control valve. It flows to the suction refrigerant inlet 1052 of the ejector 105 via 601d.

  FIG. 7 is a diagram comparing the refrigeration cycle apparatus 1010 having the first evaporator 104, the second evaporator 107, the flow path control device 1081, and the like with the conventional refrigeration cycle, that is, the Mollier diagram when the ejector is not used. is there. The solid line shows the refrigeration cycle apparatus 1010, and the broken line shows the Mollier diagram in the conventional refrigeration cycle. In FIG. 7, the refrigeration cycle apparatus 1010 is characterized in that the compressor outlet enthalpy, that is, the enthalpy at the point b, is smaller than the compressor outlet enthalpy in the conventional refrigeration cycle, that is, the enthalpy at the point b '.

The power consumption Qcomp of the compressor is obtained by the following equation (1) from the refrigerant flow rate Wr pushed by the compressor and the inlet / outlet enthalpy difference Δh of the compressor.
Qcomp = Wr × Δh (1)
From equation (1), the refrigerant flow rate Wr or Δh may be reduced in order to reduce the power consumption of the compressor. However, if the refrigerant flow rate Wr is reduced, the cooling capacity of the refrigerator is lowered, and therefore Δh needs to be reduced.

The inlet / outlet enthalpy difference Δh of the compressor 101 in the refrigeration cycle apparatus 1010 is expressed by Expression (2). Further, the conventional compressor inlet / outlet enthalpy difference Δh ′ can be expressed by Expression (3).
Δh = ha−hb (2)
Δh ′ = he−hb ′ (3)
Here, the subscripts in the expressions (2) and (3) represent the enthalpy at each point of the Mollier diagram shown in FIG. In the refrigeration cycle apparatus 1010, the outlet enthalpy of the compressor 101 is
hb <hb '
Thus, Δh can be reduced as compared with the conventional refrigeration cycle. As a result, the power consumption of the compressor 101 can be reduced.

FIG. 8 shows the relationship between the ejector efficiency η and the boost amount ΔP of the ejector. The ejector efficiency η is a ratio between the expansion power Wn and the recovery power We, and can be expressed by Expression (4).
η = We / Wn (4)
The expansion power Wn is power when the refrigerant in the state g (driving refrigerant inlet 1051) flowing into the ejector 105 adiabatically expands to the state h (FIG. 3), and can be expressed by Expression (5).
Wn = Wr1 × (hg−hh) (5)
The recovery power We is power used by the ejector 105 for boosting work, and can be expressed by Expression (6).
We = Wr2 × ΔP / ρg (6)

  That is, the ejector efficiency is increased by increasing the pressure increase amount ΔP and the suction flow rate Wr2 from the equations (4), (5), and (6).

  FIG. 8 shows the result of a cycle simulation of the refrigeration cycle apparatus 1010 using the refrigerant R404 as a working fluid. For example, when the outside air temperature is 35 ° C., the refrigerator internal temperature is 0 ° C., and the freezer temperature is −30 ° C., the amount of pressure increase increases as the ejector efficiency increases. According to FIG. 8, when the ejector efficiency is 20%, the pressure increase amount is 0.028 MPa, and when 40%, the pressure is 0.05 MPa, and the suction pressure of the compressor can be increased.

  FIG. 9 shows the COP of the refrigeration cycle apparatus 1010 when the COP of the conventional refrigeration cycle apparatus is 1. The ejector efficiency of 0% corresponds to the COP of the conventional refrigeration cycle apparatus. The COP improvement effect is improved by + 4% when the ejector efficiency is 10%, and + 7% when the ejector efficiency is 20%, and energy saving of the refrigeration cycle can be achieved.

  In the first embodiment, the flow path control device 1081 switches the flow path based on the detected pressure value of the refrigerant that has flowed out of the cooling space. For this reason, the high-pressure side refrigerant always flows into the drive refrigerant inlet 1051 of the ejector 105. As a result, the outlet pressures of the first cold chamber 001 (first evaporator 104) and the second cold chamber 002 (second evaporator 107), that is, the cooling temperatures of the first cold chamber 001 and the second cold chamber 002 are reversed. Even in this case, the power recovery operation can always be realized by using the ejector 105. Therefore, energy saving of the refrigeration cycle apparatus can be achieved.

(modularization)
In addition, mounting the ejector 105, the flow path control valves 601a to 601d, and the control unit 603 in the module structure 607 facilitates mounting on existing equipment. For this reason, construction time can be shortened. A broken line indicated by “module structure 607” in FIGS. 1, 10, and 12 indicates a housing that houses the ejector 105, the flow path control valves 601a to 601d, the control unit 603, and the like.

(Temperature detector)
Instead of the pressure detectors 602a and 602b shown in FIG. 2, temperature detectors (first detector and second detector) are attached to the refrigerant pipes of the first evaporator 104 and the second evaporator 107, and the refrigerant temperature is adjusted. The flow path switching valve 601 may be controlled based on the detected value. Further, a temperature detector may be attached to the first cold chamber 001 and the second cold chamber 002, and the flow path switching valve 601 may be controlled by comparing the temperatures in the cold chamber. The level of the refrigerant temperature of the refrigerants Wr1 and Wr2 or the level of the temperature in the cold insulation chamber corresponds to the level of the refrigerant pressure. Therefore, in these cases, the refrigerant pressure may be read as the refrigerant temperature or the temperature in the cold room in the flowchart of FIG.

Embodiment 2. FIG.
A refrigeration cycle apparatus 1020 according to the second embodiment will be described with reference to FIGS. 10 and 11. FIG. 10 shows the configuration of the flow path control device 1082 of the refrigeration cycle apparatus 1020 of the second embodiment. The refrigeration cycle apparatus 1020 is different from the refrigeration cycle apparatus 1020 in the flow path control device 1082. In the second embodiment, the flow path control device 1082 has a configuration using a three-way switching valve 608 and a check valve 609.

  The configuration of the flow path control device 1082 will be described with reference to FIG. The flow path control device 1082 includes a three-way switching valve 608, a check valve 609a (first check valve), a check valve 609b (second check valve), and the like. The first refrigerant inlet 81, the check valve 609a, and the driving refrigerant inlet 1051 of the ejector 105 are sequentially connected by a refrigerant pipe. Further, the middle (Y1) between the first refrigerant inlet 81 and the check valve 609a and the first refrigerant inlet 608-1 of the three-way switching valve 608 are connected by a pipe. The second refrigerant inlet 82 and the second refrigerant inlet 608-2 of the three-way switching valve 608 are connected by a pipe. Further, the middle (Y2) between the second refrigerant inlet 82 and the second refrigerant inlet 608-2 of the three-way switching valve 608, and the middle (Z) between the check valve 609a and the drive refrigerant inlet 1051 of the ejector 105. However, it is connected by a pipe in which a check valve 609b is arranged on the way. The refrigerant outlet 608-3 of the three-way switching valve 608 is connected to the suction refrigerant inlet 1052 of the ejector 105.

  As described above, the outlet of the first evaporator 104, the branch portion Y1, the three-way switching valve 608, and the suction refrigerant inlet 1052 of the ejector 105 are sequentially connected by the refrigerant pipe. Furthermore, the other of the branch portion Y1, the check valve 609a, the junction portion Z, and the driving refrigerant inlet 1051 of the ejector 105 are sequentially connected by refrigerant piping.

  On the other hand, the outlet of the second evaporator 107, the branch Y2, and the refrigerant inlet 608-2 are connected by refrigerant piping. The other end of the branch Y2 is connected to the check valve 609b, the junction Z and the refrigerant pipe.

  FIG. 11 is a diagram illustrating channel switching by the channel controller 1082. The operation of the flow path control device 1082 will be described with reference to FIGS. 11A shows the second flow path 72 of FIG. 1 and FIG. 11B shows the first flow path 71. The flow path control device 1082 is different in configuration from the flow path control device 1081, but the operation is the same. That is, of the refrigerants Wr1 and Wr2 flowing from the first evaporator 104 and the second evaporator 107, the refrigerant having the higher refrigerant pressure (or the refrigerant having the higher refrigerant temperature) is caused to flow into the drive refrigerant inlet 1051 of the ejector 105. The refrigerant having the lower refrigerant pressure (or the refrigerant having the lower refrigerant temperature) is caused to flow into the suction refrigerant inlet 1052.

(Wr2 pressure> Wr1 pressure)
First, the detection values of the pressure detectors 602 a and 602 b are collected in the data receiving unit 604 of the control unit 603, and the detection values are compared by the calculation unit 605. When the detected value of the pressure detector 602b is higher than the detected value of the pressure detector 602a, as shown in FIG. 11 (a), the control unit 603 causes the low-pressure refrigerant Wr1 flowing out from the first evaporator 104 to The three-way switching valve 608 is controlled so as to flow to the branch portion Y1, the three-way switching valve 608, and the suction refrigerant inlet 1052 of the ejector 105. The high-pressure refrigerant Wr2 that has flowed out of the second evaporator 107 flows to the drive refrigerant inlet 1051 of the ejector 105 through the branch portion Y2 and the check valve 609b.

(Wr2 pressure <Wr1 pressure)
On the other hand, when the detection value of the pressure detector 602b is lower than the detection value of the pressure detector 602a, the control unit 603 causes the low-pressure refrigerant Wr2 flowing out from the second evaporator 107 to be discharged as shown in FIG. , Control to pass through the three-way switching valve 608. Thereby, the high-pressure refrigerant Wr1 flowing out from the first evaporator 104 flows to the suction port 204 of the ejector 105.

  With the above operation, high-pressure refrigerant always flows into the drive refrigerant inlet 1051 of the ejector 105, so that the power recovery operation by the ejector can be performed. Therefore, the efficiency of the refrigeration cycle can be improved. Furthermore, since one control actuator (three-way switching valve) can be provided, the cost can be reduced and the electronic substrate of the control unit can be reduced in size.

Embodiment 3 FIG.
Next, a refrigeration cycle apparatus 1030 according to Embodiment 3 will be described with reference to FIG.
FIG. 12 shows a refrigeration cycle apparatus 1030 according to the third embodiment. As shown in FIG. 12, the refrigeration cycle apparatus 1030 of Embodiment 3 shows a case where the cold storage rooms of the existing facilities are expanded to three or more rooms. In such a case, the outlet of each evaporator and the ejector module can be connected without considering the temperature zone of the cooling space by the module structure 607 of the ejector and the switching valve. And by using a flow-path switching valve and a control unit, the power recovery operation by an ejector can always be implement | achieved, Therefore Energy saving of a refrigerating cycle can be aimed at.

  Although the flow path control device 1082 is used in FIG. 12, the flow path control device 1081 may be used. The configuration of the refrigeration cycle apparatus 1030 will be described below. The first refrigerant inflow port 81 of the flow path control device 1082 is connected to the refrigerant outflow side of the first evaporator 41, and the refrigerant (refrigerant A) flows from the first evaporator 41. The second refrigerant inlet 82 is connected to the mixed refrigerant outlet 1093 of the ejector 109 (second ejector), and the refrigerant (refrigerant B) flows from the ejector 109. The first refrigerant outlet 91 is connected to the drive refrigerant inlet 1051 of the ejector 105 (first ejector), and the second refrigerant outlet 92 is connected to the suction refrigerant inlet 1052 of the ejector 105. The compressor 101 has a suction side connected to the mixed refrigerant outlet of the ejector 109. The condenser 102 is connected to the discharge side of the compressor 101 by piping. The first flow control valve 51 (first pressure reducing mechanism) is connected to the refrigerant outflow side of the condenser 102 by piping. One side of the first evaporator 41 is connected to the first flow rate control valve 51 by piping, the other side is connected to the first refrigerant inlet 81 of the flow path control device 1082, and the flow path of refrigerant is controlled from the other side. Flows into device 1082. The second flow rate control valve 52 (second pressure reducing mechanism) is connected to the first branching portion 61 that branches from the middle of the piping connecting the first flow rate control valve 51 and the condenser 102 by piping. One side of the second evaporator 42 is connected to the second flow rate control valve 52 by piping. In the ejector 109, the other side of the second evaporator 42 and the suction refrigerant inlet 1092 are connected by a pipe, and the mixed refrigerant outlet 1093 is connected by a pipe to the second refrigerant inlet 82 of the flow path control device 1082. The refrigerant flows into the flow path control device 1082 from the refrigerant outlet 1093. The third flow rate control valve 53 (third pressure reducing mechanism) is connected to the second branch part 62 that branches from the middle of the pipe that connects the first branch part 61 and the condenser 102 by a pipe. One side of the third evaporator 43 is connected to the third flow rate control valve 53 by piping, and the other side is connected to the driving refrigerant inlet 1091 of the ejector 109 by piping.

  In the above configuration, the flow path control device 1082 includes the refrigerants Wr1 and Wr2 that are introduced from the first refrigerant inlet 81 and the second refrigerant inlet 82, respectively. A similar operation is performed. That is, of the refrigerants Wr1 and Wr2, the higher refrigerant pressure flows out to the driving refrigerant inlet 1051.

  8 and 9, the refrigerant R404 is taken as an example of the working fluid (refrigerant). However, a fluorocarbon refrigerant such as R410A, R32 or a mixture thereof or a hydrocarbon type such as propane, isobutane, or propylene may be used. Similar effects can be obtained. Moreover, you may apply natural refrigerants, such as CO2 and ammonia.

  Although the refrigeration cycle apparatus has been described in the above embodiment, the operation of the refrigeration cycle apparatus can be understood as the flow path switching method.

  001 1st cool room, 002 2nd cool room, 1010, 1020, 1030 Refrigeration cycle apparatus, 101 compressor, 102 condenser, 103 1st flow control valve, 104 1st evaporator, 105 ejector, 1051 Driven refrigerant inlet , 1052 Suction refrigerant inlet, 1053 Mixed refrigerant outlet, 106 Second flow control valve, 107 Second evaporator, 1081, 1082 Flow path control device, 109 Ejector, 201 Nozzle part, 201a Pressure reducing part, 201b Nozzle throat part, 201c Divergent part, 202 Mixing part, 203 Diffuser part, 601a, 601b, 601c, 601d Flow control valve, 602a, 602b Pressure detector, 603 Control unit, 607 Module structure, 608 Three-way switching valve, 609a, 609b Check valve , 71 1st flow path, 72 2nd flow path 81 First refrigerant inlet, 82 Second refrigerant inlet, 91 First refrigerant outlet, 92 Second refrigerant outlet.

Claims (13)

A driving refrigerant inlet into which the driving refrigerant flows, a suction refrigerant inlet into which the suction refrigerant sucked by the driving refrigerant flows, and a mixed refrigerant outlet from which the mixed refrigerant mixed with the driving refrigerant and the suction refrigerant flows out And an ejector in which the mixed refrigerant outlet is connected to the suction side of the compressor,
A first refrigerant inlet through which refrigerant A flows; a second refrigerant inlet through which refrigerant B flows; a first refrigerant outlet connected to the drive refrigerant inlet of the ejector; and the suction refrigerant inlet of the ejector. The refrigerant B flowing in from the first refrigerant outlet and flowing in the refrigerant B from the second refrigerant inlet Out of the second refrigerant outlet, and the refrigerant A flowing in from the first refrigerant inlet flows out of the second refrigerant outlet and flows in from the second refrigerant inlet. A flow path switching device for switching between the second flow path for allowing the refrigerant B to flow out of the first refrigerant outlet,
A compressor having a suction side connected to the mixed refrigerant outlet of the ejector;
A radiator connected by piping to the discharge side of the compressor;
A first pressure reducing mechanism connected by piping to the refrigerant outflow side of the radiator;
One side is connected to the first pressure reducing mechanism by piping, the other side is connected to the first refrigerant inflow port of the flow path switching device, and the refrigerant A flows into the flow path switching device from the other side. The first evaporator;
A second pressure reducing mechanism connected to a pipe branched from the middle of the pipe connecting the first pressure reducing mechanism and the radiator;
One side is connected to the second pressure reducing mechanism by piping, the other side is connected to the second refrigerant inlet of the flow path switching device, and the refrigerant B flows into the flow path switching device from the other side. A refrigeration cycle apparatus comprising a second evaporator. The flow path switching device is
Switching between the first flow path and the second flow path based on the state of the refrigerant A flowing into the first refrigerant inlet and the state of the refrigerant B flowing into the second refrigerant inlet. The refrigeration cycle apparatus according to claim 1. The flow path switching device further includes:
A first detector that detects either the pressure or the temperature of the refrigerant A as the state of the refrigerant A flowing into the first refrigerant inlet;
As the state of the refrigerant B flowing into the second refrigerant inlet, the pressure of the refrigerant B is detected when the first detector detects the pressure of the refrigerant A, and the first detector detects the pressure of the refrigerant A. A second detector for detecting the temperature of the refrigerant B when detecting the temperature,
The refrigeration cycle apparatus according to claim 2, wherein the first flow path and the second flow path are switched based on detection values detected by the first detector and the second detector. . The flow path switching device is
When the detection value of the first detector is higher than the detection value of the second detector, switching to the first flow path, and when the detection value of the second detector is higher than the detection value of the first detector The refrigeration cycle apparatus according to claim 3, wherein the refrigeration cycle apparatus is switched to the second flow path. The flow path switching device further includes:
A first flow path switching valve;
A second flow path switching valve;
A third flow path switching valve;
A fourth flow path switching valve;
A controller for controlling the fourth flow path switching valve from the first flow path switching valve based on detection results of the first detector and the second detector;
The first refrigerant inlet, the first flow path switching valve, and the suction refrigerant inlet of the ejector are sequentially connected by a pipe,
The second refrigerant inlet, the second flow path switching valve, and the driving refrigerant inlet of the ejector are sequentially connected by a pipe,
The third flow path switching valve is arranged in the middle of the pipe connecting from the middle of the first refrigerant inlet and the first flow path switching valve to the middle of the second flow path switching valve and the driving refrigerant inlet. And
The fourth flow path switching valve is arranged in the middle of the pipe connecting from the middle of the second refrigerant inlet and the second flow path switching valve to the middle of the first flow path switching valve and the suction refrigerant inlet. The refrigeration cycle apparatus according to claim 3, wherein the refrigeration cycle apparatus is provided. The control device includes:
When the detection value of the first detector is higher than the detection value of the second detector, the third flow path switching valve and the fourth flow path switching valve are opened, and the first flow path switching valve is opened. And the second flow path switching valve are closed,
When the detection value of the second detector is higher than the detection value of the first detector, the first flow path switching valve and the second flow path switching valve are opened, and the third flow path switching valve is opened. The refrigeration cycle apparatus according to claim 5, wherein the fourth flow path switching valve is closed. The flow path switching device further includes:
A three-way selector valve;
A first check valve;
A second check valve;
A control device for controlling the three-way switching valve based on detection results of the first detector and the second detector;
The first refrigerant inlet, the first check valve, and the drive refrigerant inlet of the ejector are sequentially connected by a refrigerant pipe,
The middle of the first refrigerant inlet and the first check valve and the first refrigerant inlet of the three-way switching valve are connected by piping,
The second refrigerant inlet and the second refrigerant inlet of the three-way switching valve are connected by piping,
The middle of the second refrigerant inlet and the second refrigerant inlet of the three-way switching valve and the middle of the first check valve and the drive refrigerant inlet of the ejector Are connected by the pipes arranged,
The refrigeration cycle apparatus according to claim 3, wherein a refrigerant outlet of the three-way switching valve is connected to the suction refrigerant inlet of the ejector. The control device includes:
When the detection value of the first detector is higher than the detection value of the second detector, the refrigerant outlet of the three-way switching valve is connected to the first refrigerant inlet, and the detection value of the second detector is 8. The refrigeration cycle apparatus according to claim 7, wherein a refrigerant outlet of the three-way switching valve is connected to the second refrigerant inlet when higher than a detection value of the first detector. The flow path switching device and the ejector are:
The refrigeration cycle apparatus according to any one of claims 1 to 8, wherein the refrigeration cycle apparatus is housed in the same casing and modularized. The refrigeration cycle apparatus includes:
The refrigeration cycle according to any one of claims 1 to 9, wherein any one of a fluorocarbon refrigerant, a mixed refrigerant, a hydrocarbon refrigerant, and a natural refrigerant is used as a working fluid that is a refrigerant. apparatus. A driving refrigerant inlet into which the driving refrigerant flows, a suction refrigerant inlet into which the suction refrigerant sucked by the driving refrigerant flows, and a mixed refrigerant outlet from which the mixed refrigerant mixed with the driving refrigerant and the suction refrigerant flows out And a first ejector in which the mixed refrigerant outlet is connected to the suction side of the compressor;
A first refrigerant inlet through which refrigerant A flows, a second refrigerant inlet through which refrigerant B flows, a first refrigerant outlet connected to the drive refrigerant inlet of the first ejector, and the first ejector of the first ejector. A second refrigerant outlet connected to the suction refrigerant inlet, the refrigerant A flowing in from the first refrigerant inlet is allowed to flow out of the first refrigerant outlet, and is introduced from the second refrigerant inlet A first flow path for allowing the refrigerant B to flow out from the second refrigerant outlet, and a flow of the refrigerant A flowing in from the first refrigerant inlet from the second refrigerant outlet, and the second refrigerant flow A flow path switching device for switching between the second flow path for allowing the refrigerant B flowing in from the inlet to flow out from the first refrigerant outlet,
A compressor having a suction side connected to the mixed refrigerant outlet of the first ejector;
A radiator connected by piping to the discharge side of the compressor;
A first pressure reducing mechanism connected by piping to the refrigerant outflow side of the radiator;
One side is connected to the first pressure reducing mechanism by piping, the other side is connected to the first refrigerant inflow port of the flow path switching device, and the refrigerant A flows into the flow path switching device from the other side. A first evaporator;
A second pressure reducing mechanism connected by piping to a first branching portion that branches from the middle of the piping connecting the first pressure reducing mechanism and the radiator;
A second evaporator having one side connected to the second decompression mechanism by piping;
The other side of the second evaporator and a suction refrigerant inlet are connected by a pipe, a mixed refrigerant outlet is connected by a pipe to the second refrigerant inlet of the flow path switching device, and the refrigerant flows from the mixed refrigerant outlet. A second ejector for flowing B into the flow path switching device;
A third decompression mechanism connected by a pipe with a second branch part that branches from the middle of the pipe connecting the first branch part and the radiator;
A refrigeration cycle apparatus comprising: a third evaporator having one side connected to the third decompression mechanism by piping and the other side connected to the driving refrigerant inlet of the second ejector by piping. A driving refrigerant inlet into which the driving refrigerant flows, a suction refrigerant inlet into which the suction refrigerant sucked by the driving refrigerant flows, and a mixed refrigerant outlet from which the mixed refrigerant mixed with the driving refrigerant and the suction refrigerant flows out And a flow path switching device connected to the drive refrigerant inlet and the suction refrigerant inlet of an ejector in which the mixed refrigerant outlet is connected to a suction side of a compressor,
A first refrigerant inlet through which refrigerant A flows; a second refrigerant inlet through which refrigerant B flows; a first refrigerant outlet connected to the drive refrigerant inlet of the ejector; and the suction refrigerant inlet of the ejector. The refrigerant B flowing in from the first refrigerant outlet and flowing in the refrigerant B from the second refrigerant inlet Out of the second refrigerant outlet, and the refrigerant A flowing in from the first refrigerant inlet flows out of the second refrigerant outlet and flows in from the second refrigerant inlet. A flow path switching device that switches between the second flow path for allowing the refrigerant B to flow out of the first refrigerant outlet. A driving refrigerant inlet into which the driving refrigerant flows, a suction refrigerant inlet into which the suction refrigerant sucked by the driving refrigerant flows, and a mixed refrigerant outlet from which the mixed refrigerant mixed with the driving refrigerant and the suction refrigerant flows out And a flow path switching device that is connected to the drive refrigerant inlet and the suction refrigerant inlet of an ejector whose mixed refrigerant outlet is connected to the suction side of the compressor, respectively, by piping. And
A first refrigerant inlet through which refrigerant A flows; a second refrigerant inlet through which refrigerant B flows; a first refrigerant outlet connected to the drive refrigerant inlet of the ejector; and the suction refrigerant inlet of the ejector. For the flow path switching device having the second refrigerant outlet connected to
A first outflow that causes the refrigerant A flowing in from the first refrigerant inflow port to flow out from the first refrigerant outflow port, and causes the refrigerant B flowing in from the second refrigerant inflow port to flow out from the second refrigerant outflow port. Method,
A second outflow that causes the refrigerant A flowing in from the first refrigerant inflow port to flow out from the second refrigerant outflow port and the refrigerant B flowing in from the second refrigerant inflow port to flow out from the first refrigerant outflow port. A flow path switching method characterized by switching between methods.

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