WO2018159322A1 - Ejector module and ejector-type refrigeration cycle - Google Patents

Abstract

This ejector module is provided with a nozzle part (15a), a depressurizing part (20b), a body part (21), a nozzle-side valve body part (22), a depressurizing-side valve body part (23), and a driving mechanism part (24). The nozzle part depressurizes and ejects a refrigerant. The depressurizing part depressurizes the refrigerant. The body part has: a refrigerant suction port (21b) which suctions the refrigerant from the outside by means of a suctioning action of an ejected refrigerant that is ejected from the nozzle part; and a pressure increasing part (15b) which increases the pressure of a refrigerant mixture of the ejected refrigerant and a suctioned refrigerant that is suctioned from the refrigerant suction port. The nozzle-side valve body part changes the cross-sectional area of the passage of the nozzle part. The depressurizing-side valve body part changes the cross-sectional area of the passage of the depressurizing part. The driving mechanism part displaces the nozzle-side valve body part and the depressurizing-side valve body part. The driving mechanism part closes the nozzle part earlier than the depressurizing part when closing the nozzle part and the depressurizing part from an open state, and opens the depressurizing part earlier than the nozzle part when opening the nozzle part and the depressurizing part from a closed state.

Description

Ejector module and ejector refrigeration cycle Cross-reference of related applications

This application is based on Japanese Patent Application No. 2017-039254 filed on March 2, 2017, the contents of which are incorporated herein by reference.

The present disclosure relates to an ejector module in which a plurality of devices including an ejector are integrated, and an ejector refrigeration cycle including the ejector.

Conventionally, an ejector type refrigeration cycle, which is a refrigeration cycle apparatus including an ejector as a refrigerant decompression device, is known. In this type of ejector-type refrigeration cycle, the pressure of the refrigerant sucked into the compressor can be made higher than the refrigerant evaporation pressure in the evaporator by the pressurizing action of the ejector. Thereby, in an ejector type refrigeration cycle, the power consumption of a compressor can be reduced and the coefficient of performance (COP) of a cycle can be improved.

Furthermore, Patent Document 1 discloses an evaporator unit applied to an ejector refrigeration cycle. The evaporator unit disclosed in Patent Document 1 includes a branching unit, an ejector, a fixed throttle, a first evaporator, a second evaporator, and the like among components constituting an ejector refrigeration cycle (in other words, unitized or modularized). ).

More specifically, the branch part branches the flow of the high-pressure refrigerant that has flowed out of the radiator, and flows it out to the nozzle part side and the fixed throttle side of the ejector. The second evaporator is a heat exchanger that evaporates the refrigerant flowing out from the diffuser portion of the ejector by exchanging heat with the blown air blown into the air-conditioning target space and evaporates the evaporated refrigerant to the suction port side of the compressor. Let The first evaporator is a heat exchanger that evaporates the refrigerant decompressed by the fixed throttle by heat exchange with the blown air that has passed through the second evaporator, and flows the evaporated refrigerant to the refrigerant suction port side of the ejector. Let

In the evaporator unit of Patent Document 1, as described above, a part of the cycle component equipment is integrated to reduce the size and productivity of the applied ejector refrigeration cycle as a whole.

Japanese Patent No. 4259531

The evaporator unit of Patent Document 1 employs a fixed throttle, and further employs a fixed nozzle portion that cannot change the passage cross-sectional area of the refrigerant passage as the nozzle portion of the ejector. For this reason, when load fluctuation occurs in the applied ejector refrigeration cycle and the flow rate of the refrigerant flowing into the nozzle portion changes, the energy conversion efficiency of the ejector may decrease.

Therefore, in the evaporator unit of Patent Document 1, when a load fluctuation occurs in the ejector-type refrigeration cycle, the ejector cannot exhibit a sufficient boosting action, and the above-described COP improvement effect cannot be obtained sufficiently. There is a fear.

On the other hand, Patent Document 1 may adopt a variable throttle mechanism configured to be able to change the passage cross-sectional area (that is, the throttle opening degree) instead of the fixed throttle, and the nozzle portion of the ejector. It is described that a variable nozzle part configured to change the passage cross-sectional area may be employed.

According to this, it is possible to suppress the decrease in the energy conversion efficiency of the ejector by adjusting the throttle opening of the variable throttle mechanism or the passage sectional area of the variable nozzle portion according to the load fluctuation of the ejector refrigeration cycle. Accordingly, it is possible to suppress a decrease in COP of the ejector refrigeration cycle even if load fluctuation occurs.

However, when a variable throttle mechanism is used instead of the fixed throttle, a drive device for changing the throttle opening is required. The same applies to the case where a variable nozzle portion is adopted as the nozzle portion of the ejector.

This type of drive is relatively large. For this reason, a unit (or module) in which constituent devices including a variable throttle mechanism or an ejector having a variable nozzle portion are integrated is likely to be large. As a result, there is a possibility that the downsizing effect of the ejector refrigeration cycle as a whole due to the integration of the components is impaired.

Furthermore, even if an ejector having a variable throttle mechanism and a variable nozzle portion is integrated, the flow rate of the refrigerant injected from the variable nozzle portion decreases during low load operation of the ejector refrigeration cycle. There is. When such a decrease in the flow rate of the injected refrigerant occurs, the ejector may not be able to exhibit a sufficient suction action and may not be able to supply a sufficient flow rate of refrigerant to the evaporator.

As a result, not only does the COP decrease, but the ejector refrigeration cycle operates improperly. Here, as an inappropriate operation of the ejector-type refrigeration cycle, a temperature distribution is generated in the fluid to be cooled that is cooled by the evaporator, and the oil mixed in the refrigerant becomes difficult to return to the compressor. And so on.

Furthermore, when the ejector-type refrigeration cycle is started, excessive refrigerant may instantaneously flow to the variable nozzle portion. In this case, the refrigerant passing sound generated by the refrigerant passing through the nozzle portion may be increased, which may be annoying. Generation | occurrence | production of such a refrigerant | coolant passage sound also corresponds to the improper operation | movement of an ejector type refrigeration cycle.

This disclosure has a first object to provide an ejector module configured such that the cross-sectional area of the passage can be changed without increasing the size of the applied ejector refrigeration cycle.

Also, a second object of the present disclosure is to provide an ejector refrigeration cycle that operates properly when a load change occurs or at startup.

The ejector module according to the first aspect of the present disclosure is applied to an ejector refrigeration cycle. The ejector module includes a nozzle part, a pressure reducing part, a body part, a nozzle side valve body part, a pressure reducing side valve body part, and a drive mechanism part. A nozzle part decompresses and injects a refrigerant. The decompression unit decompresses the refrigerant. The body portion has a refrigerant suction port that sucks the refrigerant from the outside by a suction action of the jetted refrigerant jetted from the nozzle portion, and a pressure boosting unit that boosts the mixed refrigerant of the jetted refrigerant and the sucked refrigerant sucked from the refrigerant suction port . The nozzle side valve body changes the passage cross-sectional area of the nozzle. The pressure reducing side valve body portion changes the passage cross-sectional area of the pressure reducing portion. The drive mechanism displaces the nozzle side valve body and the pressure reducing side valve body. When the drive mechanism portion closes the nozzle portion and the pressure reducing portion from the opened state, the drive mechanism portion closes the nozzle portion before the pressure reducing portion, and further, when the nozzle portion and the pressure reducing portion are opened from the closed state. The decompression part is opened before the nozzle part.

According to this, since the nozzle part, the body part, the nozzle side valve body part, and the drive mechanism part are provided, an ejector having a variable nozzle part can be configured. Furthermore, since the pressure reducing part, the pressure reducing side valve body part, and the drive mechanism part are provided, a variable throttle mechanism can be configured.

Therefore, the ejector having the variable nozzle portion and the variable aperture mechanism can be integrated. At this time, the passage cross-sectional area of the nozzle part and the throttle opening of the pressure reducing part are adjusted by one common driving mechanism part, so that it can be changed without increasing the size of the one having a plurality of driving mechanism parts. The ejector having the nozzle portion and the variable aperture mechanism can be integrated.

Further, when the drive mechanism portion closes the nozzle portion and the pressure reducing portion, the nozzle portion is closed before the pressure reducing portion, and when the nozzle portion and the pressure reducing portion are opened, the pressure reducing portion is preceded by the nozzle portion. open.

Therefore, in the ejector-type refrigeration cycle including the ejector module according to the first aspect, it is possible to switch to a normal refrigeration cycle apparatus that does not cause the ejector to function during an operating condition in which the ejector cannot exhibit a sufficient suction action or boosting action due to load fluctuations. And it can be operated appropriately as a normal refrigeration cycle apparatus.

That is, according to the first aspect, it is possible to provide an ejector module configured such that the passage cross-sectional area can be changed without increasing the size of the applied ejector-type refrigeration cycle. Furthermore, it is possible to provide an ejector refrigeration cycle that operates properly even when load fluctuation occurs.

The ejector refrigeration cycle according to the second aspect of the present disclosure includes a compressor, a radiator, a branching unit, an ejector, a variable throttle mechanism, an ejector control unit, and a stop condition determination unit. The compressor compresses and discharges the refrigerant. The radiator dissipates heat from the refrigerant discharged from the compressor. A branch part branches the flow of the refrigerant | coolant which flowed out from the heat radiator. The ejector sucks the refrigerant from the refrigerant suction port by the suction action of the jet refrigerant ejected from the variable nozzle portion that depressurizes one of the refrigerant branched at the branch portion, and sucked refrigerant sucked from the jet refrigerant and the refrigerant suction port And pressurize the mixed refrigerant. The variable throttle mechanism depressurizes the other refrigerant branched at the branch portion. The first evaporator evaporates the refrigerant decompressed by the variable throttle mechanism and causes the refrigerant to flow out to the refrigerant suction port side. The second evaporator evaporates the refrigerant that has flowed out of the ejector and flows it out to the suction side of the compressor. The ejector control unit controls the passage sectional area of the variable nozzle unit. The stop condition determination unit determines that a predetermined ejector stop condition is satisfied. The ejector control unit closes the variable nozzle unit when the stop condition determining unit determines that the ejector stop condition is satisfied.

According to this, when it is determined by the stop condition determining unit that the ejector stop condition is satisfied, the ejector control unit closes the variable nozzle unit. Therefore, it is possible to switch to a normal refrigeration cycle apparatus that does not cause the ejector to function during an operating condition in which the ejector cannot exhibit a sufficient suction action or boosting action due to load fluctuations. And it can be operated appropriately as a normal refrigeration cycle apparatus.

That is, according to the second aspect, it is possible to provide an ejector-type refrigeration cycle that operates properly when a load change occurs or at startup.

It is a whole block diagram of the ejector-type refrigeration cycle of at least one embodiment. It is an axial sectional view of the ejector module of at least one embodiment. It is the III section enlarged view of FIG. FIG. 4 is a sectional view taken along line IV-IV in FIG. 3. FIG. 5 is a VV cross-sectional view of FIG. 3. It is a control characteristic figure which shows the relationship between the opening degree of the nozzle part of at least 1 embodiment, and the opening degree of a throttle path. It is a block diagram of the electric control unit of the ejector refrigeration cycle of at least one embodiment. It is a flowchart which shows the control processing of the ejector-type refrigeration cycle of at least 1 embodiment. It is a whole block diagram of the ejector-type refrigeration cycle of at least one embodiment. It is a block diagram of the electric control unit of the ejector refrigeration cycle of at least one embodiment. It is a whole block diagram of the ejector-type refrigeration cycle of at least one embodiment.

Hereinafter, a plurality of modes for carrying out the present disclosure will be described with reference to the drawings. In each embodiment, parts corresponding to the matters described in the preceding embodiment may be denoted by the same reference numerals, and redundant description may be omitted. When only a part of the configuration is described in each mode, the other modes described above can be applied to the other parts of the configuration. Not only combinations of parts that clearly show that combinations are possible in each embodiment, but also combinations of the embodiments even if they are not explicitly stated unless there is a problem with the combination. Is also possible.

(First embodiment)
1st Embodiment of this indication is described using FIGS. 1-8. The ejector module 20 of the present embodiment is applied to an ejector refrigeration cycle 10 that is a vapor compression refrigeration cycle apparatus including an ejector as a refrigerant decompression device, as shown in the overall configuration diagram of FIG. This ejector-type refrigeration cycle 10 is applied to a vehicle air conditioner, and fulfills a function of cooling blown air that is blown into a vehicle interior that is a space to be cooled. Therefore, the fluid to be cooled in the ejector refrigeration cycle 10 is blown air.

The ejector refrigeration cycle 10 employs an HFC refrigerant (specifically, R134a) as a refrigerant, and constitutes a subcritical refrigeration cycle in which the high-pressure side refrigerant pressure of the cycle does not exceed the critical pressure of the refrigerant. Furthermore, refrigeration oil for lubricating the compressor 11 is mixed in the refrigerant. As the refrigerating machine oil, a PAG oil having compatibility with a liquid phase refrigerant is employed. A part of the refrigerating machine oil circulates in the cycle together with the refrigerant.

Among the constituent devices of the ejector refrigeration cycle 10, the compressor 11 sucks the refrigerant and compresses and discharges it until it becomes a high-pressure refrigerant. More specifically, the compressor 11 of the present embodiment is an electric compressor that is configured by housing a fixed capacity type compression mechanism and an electric motor that drives the compression mechanism in one housing.

As this compression mechanism, various compression mechanisms such as a scroll-type compression mechanism and a vane-type compression mechanism can be employed. Further, the operation (rotation speed) of the electric motor is controlled by a control signal output from the air conditioning control device 40, and either an AC motor or a DC motor may be adopted.

The refrigerant inlet side of the condenser 12 a of the radiator 12 is connected to the discharge port of the compressor 11. The radiator 12 is a heat dissipation heat exchanger that radiates and cools the high-pressure refrigerant by exchanging heat between the high-pressure refrigerant discharged from the compressor 11 and the outside air (outside air) blown from the cooling fan 12c. is there.

More specifically, the radiator 12 is configured as a so-called receiver-integrated condenser having a condensing part 12a and a receiver part 12b. The condensing unit 12a is a heat exchanging unit for condensation that exchanges heat between the high-pressure gas-phase refrigerant discharged from the compressor 11 and the outside air blown from the cooling fan 12c, and dissipates the high-pressure gas-phase refrigerant to condense. . The receiver unit 12b is a refrigerant container that separates the gas-liquid refrigerant flowing out from the condensing unit 12a and stores excess liquid-phase refrigerant.

The cooling fan 12c is an electric blower in which the rotation speed (the amount of blown air) is controlled by a control voltage output from the air conditioning control device 40. The refrigerant outlet of the receiver section 12 b of the radiator 12 is connected to the high pressure inlet 21 a side provided in the body section 21 of the ejector module 20.

The ejector module 20 is obtained by integrating (in other words, modularizing) a part of the cycle constituent devices constituting the ejector refrigeration cycle 10. More specifically, the ejector module 20 of the present embodiment is obtained by integrating the branching unit 14, the ejector 15, the variable throttle mechanism 16 and the like among the cycle constituent devices.

The branch part 14 branches the flow of the refrigerant that has flowed out of the radiator 12, injects one of the branched refrigerants from the nozzle part 15a of the ejector 15, and causes the other branched refrigerant to flow out to the variable throttle mechanism 16. Fulfill. The branch portion 14 is formed by connecting a space formed in the body portion 21 of the ejector module 20 and a refrigerant passage.

The ejector 15 has a nozzle portion 15a that depressurizes and injects one of the refrigerants branched at the branching portion 14, and functions as a refrigerant decompression device. Further, the ejector 15 functions as a refrigerant circulation device that sucks and circulates the refrigerant from outside by the suction action of the refrigerant injected from the refrigerant injection port of the nozzle portion 15a. More specifically, the ejector 15 sucks the refrigerant that has flowed out of the first evaporator 17 described later.

In addition, the ejector 15 converts the kinetic energy of the mixed refrigerant of the refrigerant injected from the nozzle portion 15a and the refrigerant sucked from the refrigerant suction port 21b formed in the body portion 21 into pressure energy. It functions as an energy conversion device that boosts the pressure of the mixed refrigerant. The ejector 15 causes the pressurized refrigerant to flow out to the refrigerant inlet side of the second evaporator 18 described later. The nozzle portion 15a of the ejector 15 is configured such that the passage cross-sectional area can be changed.

The variable throttle mechanism 16 has a throttle passage 20b that depressurizes the other refrigerant branched by the branching section 14. The variable throttle mechanism 16 is configured to be able to change the passage cross-sectional area (that is, the throttle opening) of the throttle passage 20b. The variable throttle mechanism 16 causes the decompressed refrigerant to flow out to the refrigerant inlet side of the first evaporator 17.

Next, the detailed configuration of the ejector module 20 will be described with reference to FIGS. First, as shown in FIG. 2, the ejector module 20 includes a body part 21, a needle valve 22, a throttle valve 23, a drive mechanism part 24, and the like.

The body part 21 is formed by combining a plurality of structural members made of metal (in this embodiment, made of aluminum). The body portion 21 forms an outer shell of the ejector module 20 and forms part of components such as the ejector 15 and the variable aperture mechanism 16. The body part 21 may be formed of resin.

The body section 21 is provided with a plurality of refrigerant inlets and outlets such as a high-pressure inlet 21a, a refrigerant suction port 21b, an ejector side outlet 21c, and a throttle side outlet 21d.

The high-pressure inlet 21 a is a refrigerant inlet through which the refrigerant that has flowed out from the refrigerant outlet of the receiver unit 12 b of the radiator 12 flows into the ejector module 20. Accordingly, the high-pressure inlet 21 a serves as a refrigerant inlet for the branch portion 14. The refrigerant suction port 21 b is a refrigerant inlet that sucks the refrigerant flowing out of the first evaporator 17. The suction refrigerant sucked from the refrigerant suction port 21b merges with the jet refrigerant jetted from the nozzle portion 15a.

The ejector side outlet 21c is a refrigerant outlet through which the refrigerant whose pressure has been increased by the ejector 15 (specifically, a diffuser portion 15b described later) flows out to the inlet side of the second evaporator 18. The throttle-side outlet 21 d is a refrigerant outlet that allows the refrigerant decompressed by the variable throttle mechanism 16 to flow out to the inlet side of the first evaporator 17.

As shown in FIG. 3, a turning space 20a is formed inside the body portion 21. The swirling space 20a is formed in a columnar shape, and is a space that swirls the refrigerant flow that has flowed in from the high-pressure inlet 21a around the central axis.

As shown in FIG. 4, the refrigerant passage connecting the high-pressure inlet 21a and the swirl space 20a allows the refrigerant flowing into the swirl space 20a when viewed from the central axis direction of the swirl space 20a to flow into the inner wall surface of the swirl space 20a. It is formed to flow along. Thereby, the refrigerant flowing into the swirling space 20a swirls around the central axis of the swirling space 20a.

As shown in FIG. 2, the nozzle portion 15 a of the ejector 15 is disposed on one end side in the axial direction of the swirling space 20 a of the body portion 21. The inlet of the nozzle portion 15a opens into the swirling space 20a. The refrigerant passage of the nozzle portion 15a is formed with a throat portion that reduces the refrigerant passage cross-sectional area, and a divergent portion in which the passage cross-sectional area gradually increases as it goes from the throat to the refrigerant injection port that injects the refrigerant. .

That is, the nozzle portion 15a is configured as a Laval nozzle. Further, in the present embodiment, the nozzle portion 15a is set such that the flow rate of the injected refrigerant injected from the refrigerant injection port during the normal operation of the ejector refrigeration cycle 10 is equal to or higher than the sound speed. Of course, you may comprise the nozzle part 15a with a tapered nozzle.

The entrance of the throttle passage 20b is open on the other axial end side of the swirling space 20a. For this reason, the high-pressure refrigerant flowing into the swirling space 20a from the high-pressure inlet 21a flows into both the nozzle portion 15a and the throttle passage 20b from the swirling space 20a. That is, in this embodiment, the branch part 14 is formed in the turning space 20a.

The throttle passage 20b is a decompression unit that decompresses the refrigerant by reducing the cross-sectional area of the passage. The throttle passage 20b is formed in a rotating body shape such as a columnar shape or a truncated cone shape. In the present embodiment, an orifice formed as a separate member with respect to the body portion 21 is employed as the throttle passage 20b, and is fixed to the body portion 21 by means such as press fitting.

Furthermore, the central axis of the swirl space 20a, the central axis of the nozzle portion 15a, and the central axis of the throttle passage 20b are arranged coaxially with each other. Accordingly, the nozzle portion 15a and the throttle passage 20b of the present embodiment are arranged side by side in the axial direction of the nozzle portion 15a.

A diffuser portion 15b is disposed on the downstream side of the refrigerant flow of the nozzle portion 15a of the body portion 21. The diffuser unit 15b is a pressure increasing unit that increases the pressure of the mixed refrigerant. The diffuser portion 15b is formed of a cylindrical metal (in this embodiment, aluminum). A refrigerant suction port 21b is formed on the cylindrical side surface of the diffuser portion 15b so as to penetrate the inside and outside of the diffuser portion 15b.

Inside the diffuser portion 15b, there are formed a space in which the nozzle portion 15a is accommodated, a refrigerant passage through which the mixed refrigerant of the injected refrigerant and the suction refrigerant circulates, and the like. The refrigerant passage is formed in a substantially truncated cone shape whose passage cross-sectional area gradually increases toward the downstream side of the refrigerant flow. In the diffuser portion 15b, the kinetic energy of the mixed refrigerant can be converted into pressure energy by such a passage shape.

The needle valve 22 is a nozzle-side valve body portion that is disposed in a refrigerant passage formed inside the nozzle portion 15a and changes the passage cross-sectional area of the refrigerant passage. The needle valve 22 is made of a needle-like (or a shape obtained by combining a conical shape, a cylindrical shape, or the like) metal (in this embodiment, stainless steel).

The central axis of the needle valve 22 is arranged coaxially with the central axis of the nozzle portion 15a, the central axis of the refrigerant passage of the diffuser portion 15b, and the like. The needle valve 22 is displaced in the central axis direction to change the passage cross-sectional area of the nozzle portion 15a. Furthermore, the needle valve 22 can also close the nozzle portion 15a by contacting the throat portion.

Here, as shown in FIG. 5, a plurality of support portions 15c for slidably supporting the outer peripheral surface of the needle valve 22 are formed on the inner peripheral surface of the nozzle portion 15a. Thereby, when the needle valve 22 is displaced, the center axis of the needle valve 22 is prevented from being displaced from the center axis of the nozzle portion 15a. The refrigerant that has flowed into the nozzle portion 15a from the swirling space 20a flows between the adjacent support portions 15c.

Further, a coil spring 22c is disposed in the swirling space 20a. The coil spring 22c is an elastic member that applies a load to the needle valve 22 on the side that reduces (closes) the passage cross-sectional area of the nozzle portion 15a.

The throttle valve 23 is a decompression side valve body portion that is arranged on the refrigerant flow downstream side of the throttle passage 20b (that is, the side opposite to the nozzle portion 15a) and changes the passage cross-sectional area on the outlet side of the throttle passage 20b. The throttle valve 23 is made of the same material as the needle valve 22. The throttle valve 23 is formed in a truncated cone shape whose outer diameter on the bottom side is larger than the outer diameter of the needle valve 22.

Thereby, the inlet of the throttle passage 20b formed in an annular shape around the throttle valve 23 is formed on the outer peripheral side of the central axis rather than the inlet of the nozzle portion 15a formed in an annular shape around the needle valve 22. ing.

The central axis of the throttle valve 23 is arranged coaxially with the central axis of the needle valve 22. The throttle valve 23 changes the passage cross-sectional area of the throttle passage 20b by being displaced in the central axis direction. Furthermore, the throttle valve 23 can also close the throttle passage 20b by contacting the outlet of the throttle passage 20b.

The driving mechanism 24 is connected to the opposite side of the nozzle portion 15a of the throttle valve 23. The drive mechanism unit 24 displaces the needle valve 22 and the throttle valve 23 in the central axis direction, and is connected to the throttle valve 23. The drive mechanism unit 24 is an electric actuator having a stepping motor. The operation of the drive mechanism unit 24 is controlled by a control voltage (control pulse) output from the air conditioning control device 40.

As shown in FIG. 3, a connecting portion 23a connected to the needle valve 22 is provided at the center of the throttle valve 23 on the nozzle portion 15a side. The connecting portion 23a has a thin shaft portion extending in the axial direction of the throttle valve 23, and a disk-shaped portion extending in the radial direction from the thin shaft portion. The needle valve 22 is formed with an engagement hole 22a into which the disk-shaped portion of the connecting portion 23a is fitted from the radial direction.

The axial dimension W of the engagement hole 22a is formed larger than the axial thickness dimension T of the disk-shaped part of the connecting part 23a. Accordingly, a gap is formed in the axial direction between the connecting portion 23 a of the throttle valve 23 and the inner wall surface of the engagement hole 22 a of the needle valve 22. Furthermore, a contact portion 22b that contacts the connecting portion 23a is formed in the surface of the throttle valve 23 inside the engagement hole 22a.

As a result, as shown in FIG. 6, the drive mechanism section 24 closes the nozzle section 15a before the throttle path 20b when both the nozzle section 15a and the throttle path 20b are closed. I have to. Further, when the drive mechanism 24 is opened from a state in which both the nozzle portion 15a and the throttle passage 20b are closed, the throttle passage 20b is opened before the nozzle portion 15a.

Here, FIG. 6 shows the opening degree of the nozzle part 15a and the opening degree of the throttle passage 20b with respect to the count number of control pulses output to the stepping motor of the drive mechanism part 24. In FIG. 6, the opening degree 0 means a state in which the nozzle portion 15a or the throttle passage 20b is closed.

More specifically, in the state where the throttle valve 23 fully opens the throttle passage 20b and the needle valve 22 fully opens the nozzle portion 15a (C3 in FIG. 6), the contact of the needle valve 22 by the action of the coil spring 22c. The portion 22 b is in contact with the connecting portion 23 a of the throttle valve 23.

From this state, when the drive mechanism 24 displaces the throttle valve 23 to the side of reducing the passage sectional area of the throttle passage 23b, the needle valve 22 also reduces the passage sectional area of the nozzle portion 15a by the action of the coil spring 22c. Displace to When the needle valve 22 comes into contact with the throat portion of the nozzle portion 15a, the nozzle portion 15a is closed (C2 in FIG. 6). At this time, the throttle valve 23 is not in contact with the outlet of the throttle passage 20b, and the throttle passage 20b is open.

Since a gap is formed in the axial direction between the coupling portion 23a of the throttle valve 23 and the engagement hole 22a of the needle valve 22, even if the needle valve 22 is in contact with the throat portion of the nozzle portion 15a, The throttle valve 23 can be displaced to the side that reduces the cross-sectional area of the throttle passage 23b. When the throttle valve 23 comes into contact with the outlet of the throttle passage 20b, the throttle passage 20b is closed behind the nozzle portion 15a (C1 in FIG. 6).

Conversely, from the state (C1 in FIG. 6) in which the throttle valve 23 closes the throttle passage 20b and the needle valve 22 closes the nozzle portion 15a (C1 in FIG. 6), the drive mechanism portion 24 reduces the passage sectional area of the throttle passage 20b. When the throttle valve 23 is displaced to the side to be enlarged, the throttle passage 20b is opened. At this time, the nozzle portion 15a remains blocked by the action of the coil spring 22c until the connecting portion 23a of the throttle valve 23 contacts the contact portion 22b of the needle valve 22.

Then, when the driving mechanism 24 displaces the throttle valve 23 from the state in which the connecting portion 23a is in contact with the contact portion 22b to the side that enlarges the passage cross-sectional area of the throttle passage 20b, the needle valve 22 and the throttle valve 23 are moved together. As a result of the displacement, the nozzle portion 15a begins to open behind the throttle passage 20b (C2 in FIG. 6). In other words, the needle valve 22 is displaced in conjunction with the throttle valve 23 when the connecting portion 23 a of the throttle valve 23 is in contact with the contact portion 22 b of the needle valve 22.

As is clear from the above description, in the ejector module 20, the passage sectional area of the nozzle portion 15a is constituted by the nozzle portion 15a, the refrigerant suction port 21b of the body portion 21, the diffuser portion 15b, the needle valve 22, the drive mechanism portion 24, and the like. An ejector 15 having a variable nozzle portion configured to be changeable is configured.

Further, in the ejector module 20, the variable throttle mechanism 16 configured such that the passage sectional area (that is, the throttle opening) of the throttle passage 20b can be changed by the throttle passage 20b, the throttle valve 23, the drive mechanism unit 24, and the like. Has been.

Next, the second evaporator 18 shown in FIG. 1 includes the blown air blown from the blower 18a toward the vehicle interior and the ejector side outlet 21c of the ejector module 20 (that is, the refrigerant outlet of the diffuser portion 15b of the ejector 15). Heat exchange with the low-pressure refrigerant that has flowed out of the tank. And it is a heat exchanger for heat absorption which cools blowing air by evaporating this low-pressure refrigerant, and exhibiting an endothermic effect.

The blower 18a is an electric blower in which the rotation speed (the amount of blown air) is controlled by a control voltage output from the air conditioning control device 40. The refrigerant outlet of the second evaporator 18 is connected to the low pressure inlet 21 e side of the ejector module 20.

The first evaporator 17 exchanges heat between the blown air that has passed through the second evaporator 18 and the low-pressure refrigerant that has flowed out from the throttle-side outlet 21d of the ejector module 20 (that is, the refrigerant outlet of the variable throttle mechanism 16). And it is a heat exchanger for heat absorption which cools blowing air by evaporating this low-pressure refrigerant, and exhibiting an endothermic effect. The refrigerant outlet of the second evaporator 18 is connected to the refrigerant suction port 21 b side of the ejector module 20.

Further, the first evaporator 17 and the second evaporator 18 of the present embodiment are integrally configured. Specifically, each of the first evaporator 17 and the second evaporator 18 includes a plurality of tubes that circulate the refrigerant, and a collection or distribution of refrigerants that are arranged on both ends of the plurality of tubes and circulate through the tubes. And a so-called tank-and-tube heat exchanger having a pair of collective distribution tanks.

The first evaporator 17 and the second evaporator 18 are integrated by forming the collective distribution tank of the first evaporator 17 and the second evaporator 18 with the same member. At this time, in the present embodiment, the first evaporator 17 and the second evaporator 18 are changed to the blown air flow so that the second evaporator 18 is arranged on the upstream side of the blower air flow with respect to the first evaporator 17. In contrast, they are arranged in series. Accordingly, the blown air flows as shown by the arrows drawn by the two-dot chain line in FIG.

Next, the electric control unit of the ejector refrigeration cycle 10 will be described. The air conditioning control device 40 is composed of a well-known microcomputer including a CPU, ROM, RAM, and its peripheral circuits, and performs various calculations and processing based on a control program stored in the ROM, and is connected to the output side. The operation of various control target devices 11, 12c, 18a, 20 and the like is controlled.

On the input side of the air conditioning control device 40, as shown in the block diagram of FIG. 7, the inside air temperature sensor 41, the outside air temperature sensor 42, the solar radiation sensor 43, the discharge refrigerant pressure sensor 44, the intake refrigerant pressure sensor 45, and the intake refrigerant temperature sensor. 46, an evaporator temperature sensor 47 and the like are connected. And the detection signal of these sensor groups is input into the air-conditioning control apparatus 40. FIG.

The inside air temperature sensor 41 is an inside air temperature detecting unit that detects a vehicle interior temperature (inside air temperature) Tr. The outside air temperature sensor 42 is an outside air temperature detecting unit that detects a vehicle compartment outside temperature (outside air temperature) Tam. The solar radiation sensor 43 is a solar radiation amount detection unit that detects the solar radiation amount As irradiated into the vehicle interior.

The discharge refrigerant pressure sensor 44 is a discharge pressure detection unit that detects the discharge refrigerant pressure Pd of the discharge refrigerant discharged from the compressor 11. The suction refrigerant pressure sensor 45 is a suction pressure detection unit that detects the suction refrigerant pressure Ps of the suction refrigerant sucked into the compressor 11. The intake refrigerant temperature sensor 46 is an intake temperature detection unit that detects an intake refrigerant temperature Ts of the intake refrigerant sucked into the compressor 11.

The evaporator temperature sensor 47 is an evaporator temperature detector that detects the refrigerant evaporation temperature (evaporator temperature) Tefin in the first evaporator 17. The evaporator temperature sensor 47 is formed by a plurality of temperature sensors. Therefore, the evaporator temperature sensor 47 can detect temperatures of a plurality of parts of the first evaporator 17.

More specifically, at least one of the evaporator temperature sensors 47 detects the temperature of the refrigerant inlet portion of the first evaporator 17, and at least another one of the temperatures of the refrigerant outlet portion of the first evaporator 17. Is detected.

For this reason, in the air conditioning control device 40, the average value of the detected values detected by the plurality of temperature sensors is set as the refrigerant evaporation temperature (evaporator temperature) Tefin. Further, the air conditioning control device 40 can detect the temperature difference ΔT obtained by subtracting the minimum temperature from the maximum temperature of these detection values as the temperature distribution of the blown air blown from the first evaporator 17.

Furthermore, the input side of the air conditioning control device 40 is connected to an operation panel 50 disposed near the instrument panel in the front part of the passenger compartment, and operation signals from various operation switches provided on the operation panel 50 are input.

Specifically, the various operation switches provided on the operation panel 50 include an auto switch for setting or canceling the automatic control operation of the vehicle air conditioner, an air volume setting switch for manually setting the air volume of the blower 18a, and a target temperature in the passenger compartment. There is a temperature setting switch for setting Tset.

The air-conditioning control device 40 according to the present embodiment is configured such that a control unit that controls various control target devices connected to the output side thereof is integrally configured. However, the configuration controls the operation of each control target device. (Hardware and Software) constitutes a control unit that controls the operation of each control target device.

For example, in the air-conditioning control device 40, the configuration for controlling the refrigerant discharge capacity of the compressor 11 (specifically, the rotational speed of the compressor 11) constitutes a discharge capacity control unit 40a. The configuration for controlling the operation of the ejector module 20 (specifically, the drive mechanism unit 24) constitutes an ejector control unit 40b.

Next, the operation of this embodiment in the above configuration will be described. In the ejector type refrigeration cycle 10 of the present embodiment, it is possible to switch between normal operation and ejector stop operation.

These operations are switched by the air conditioning control device 40 executing an air conditioning control program stored in advance in a storage circuit. This air conditioning control program is executed when the auto switch of the operation panel 50 is turned on. Note that each control step in the air conditioning control program constitutes a function realization unit included in the air conditioning control device.

First, normal operation will be described. In the main routine of the air conditioning control program, the target blowing temperature TAO of the blown air blown into the vehicle interior is determined based on the detection signal of the air conditioning control sensor group and the operation signal from the operation panel. And the air-conditioning control apparatus 40 controls the action | operation of the compressor 11, the air blower 18a, the ejector module 20, etc. according to the target blowing temperature TAO.

The liquid phase refrigerant separated by the receiver unit 12b flows into the high-pressure inlet 21a of the ejector module 20. The refrigerant that has flowed into the ejector module 20 is branched at the branching section 14. One of the branched refrigerant flows into the nozzle portion 15a of the ejector 15 and is isentropically decompressed and injected. And the refrigerant | coolant which flowed out from the 1st evaporator 17 is attracted | sucked from the refrigerant | coolant suction port 21b by the suction effect | action of this injection refrigerant | coolant.

At this time, the air conditioning control device 40 calculates the superheat degree of the intake refrigerant based on the intake refrigerant pressure Ps detected by the intake refrigerant pressure sensor 45 and the intake refrigerant temperature Ts detected by the intake refrigerant temperature sensor 46. The operation of the drive mechanism unit 24 of the ejector module 20 is controlled so that the superheated degree approaches the predetermined reference superheat degree (1 ° C. in the present embodiment).

The refrigerant injected from the nozzle portion 15a and the suction refrigerant sucked from the refrigerant suction port 21b flow into the diffuser portion 15b. In the diffuser portion 15b, the velocity energy of the refrigerant is converted into pressure energy by expanding the refrigerant passage area. Thereby, the pressure of the mixed refrigerant of the injection refrigerant and the suction refrigerant increases. The refrigerant whose pressure has been increased in the diffuser portion 15b flows out from the ejector side outlet 21c.

The refrigerant that has flowed out of the ejector side outlet 21c flows into the second evaporator 18. The refrigerant flowing into the second evaporator 18 absorbs heat from the blown air blown by the blower 18a and evaporates. Thereby, the blowing air blown by the blower 18a is cooled. The refrigerant flowing out from the second evaporator 18 is sucked into the compressor 11 and compressed again.

On the other hand, the other refrigerant branched at the branch portion 14 flows into the throttle passage 20b of the variable throttle mechanism 16 and is decompressed in an enthalpy manner. The refrigerant decompressed by the variable throttle mechanism 16 flows out from the throttle-side outlet 21d and flows into the first evaporator 17. The refrigerant flowing into the first evaporator 17 absorbs heat from the blown air after passing through the second evaporator 18 and evaporates. Thereby, the blown air after passing through the second evaporator 18 is further cooled. The refrigerant flowing out from the first evaporator 17 is sucked from the refrigerant suction port 21b.

As described above, in the ejector-type refrigeration cycle 10 during normal operation, the blown air blown into the vehicle compartment can be cooled by the first evaporator 17 and the second evaporator 18.

Furthermore, during normal operation, the refrigerant on the downstream side of the second evaporator 18, that is, the refrigerant whose pressure has been increased by the diffuser portion 15 b of the ejector 15 can be sucked into the compressor 11. Therefore, in the ejector-type refrigeration cycle 10, the power consumption of the compressor 11 is reduced and the coefficient of performance (COP) of the cycle is reduced as compared with a normal refrigeration cycle apparatus in which the refrigerant evaporation pressure in the evaporator is equal to the suction refrigerant pressure. Can be improved.

Further, during normal operation, the refrigerant evaporation pressure in the second evaporator 18 becomes the refrigerant pressure increased by the diffuser portion 15b, and the low refrigerant immediately after the refrigerant evaporation pressure in the first evaporator 17 is reduced by the nozzle portion 15a. It becomes pressure. Therefore, the temperature difference between the refrigerant evaporation temperature and the blown air in each evaporator can be secured and the blown air can be efficiently cooled.

Further, since the ejector refrigeration cycle 10 of the present embodiment includes the ejector module 20, the passage sectional area of the nozzle portion 15 a of the ejector 15 and the variable throttle mechanism 16 according to the load fluctuation of the ejector refrigeration cycle 10. The throttle opening degree can be changed. Therefore, it is possible to suppress a decrease in COP of the ejector refrigeration cycle 10 even when load fluctuation occurs.

Further, in the ejector module 20 of the present embodiment, the passage cross-sectional area of the nozzle portion 15a and the throttle opening degree of the throttle passage 20b can be adjusted by a single common drive mechanism portion 24, so that a plurality of drive mechanism portions can be adjusted. The ejector 15 having the variable nozzle portion and the variable aperture mechanism 16 can be integrated without increasing the size.

As a result, according to the ejector module 20 of the present embodiment, the applied ejector refrigeration cycle 10 is not enlarged even if the passage cross-sectional area is configured to be changeable.

By the way, even in the case of the ejector refrigeration cycle 10 that can change the passage sectional area of the nozzle portion 15a of the ejector 15 and the throttle opening of the variable throttle mechanism 16 as in the present embodiment, during low load operation, etc. In some cases, the flow rate of the refrigerant flowing into the nozzle portion 15a of the ejector 15 decreases, and the flow rate of the injected refrigerant decreases.

When such a decrease in the flow rate of the injection refrigerant occurs, the ejector 15 cannot exhibit a sufficient suction action, and a sufficient amount of refrigerant can be supplied to the first evaporator 17 and the second evaporator 18. It becomes impossible. As a result, not only the COP is lowered, but also a temperature distribution of the blown air cooled by the first evaporator 17 and the second evaporator 18 may be caused.

Therefore, in the ejector refrigeration cycle 10 of the present embodiment, the air conditioning control device 40 executes the control process shown in FIG. 8 as a subroutine of the main routine described above. This control process is executed every predetermined control cycle.

First, in step S1 of FIG. 8, it is determined whether or not a predetermined ejector stop condition is satisfied. Therefore, the control step S1 of this embodiment constitutes a stop condition determination unit. More specifically, in step S1 of the present embodiment, the ejector stop condition is satisfied when the temperature difference ΔT detected by the evaporator temperature sensor 47 is equal to or greater than a predetermined reference temperature difference KΔT. judge.

When it is determined in step S1 that the ejector stop condition is satisfied, the process proceeds to step S2, and the ejector stop operation is executed. If it is not determined in step S1 that the ejector stop condition is satisfied, the process returns to the main routine and normal operation is performed.

In the ejector stop operation in step S2, the air conditioning control device 40 controls the operation of the ejector module 20 so as to close the nozzle portion 15a of the ejector 15 with the throttle passage 20b opened. More specifically, the drive mechanism of the ejector module 20 is set so that the superheat degree of the suction refrigerant approaches a predetermined reference superheat degree (1 ° C. in the present embodiment) within the range of C1 to C2 in FIG. The operation of the unit 24 is controlled.

Therefore, in the ejector stop operation, the compressor 11 → the radiator 12 → the throttle passage 20b of the ejector module 20 → the first evaporator 17 (→ the diffuser portion 15b of the ejector module 20) → the second evaporator 18 → the compressor 11 in this order. The refrigeration cycle in which the refrigerant circulates is configured. In this cycle configuration, since the refrigerant is not injected from the nozzle portion 15a of the ejector 15, the diffuser portion 15b functions as a refrigerant passage without exhibiting a pressure increasing action.

That is, in the ejector stop operation, the ejector refrigeration cycle 10 is switched to a normal vapor compression refrigeration cycle apparatus that does not cause the ejector 15 to function. According to this, even under operating conditions in which the ejector 15 cannot exhibit a sufficient suction action or pressure increase action, a sufficient flow rate is supplied to the first evaporator 17 and the second evaporator 18 by the suction and discharge actions of the compressor 11. The refrigerant can be supplied.

Therefore, the ejector refrigeration cycle 10 can be appropriately operated even under operating conditions in which the ejector 15 cannot exhibit a sufficient suction action or pressure increase action, such as when a load fluctuates or during startup. .

More specifically, the expansion of the temperature distribution of the blown air cooled by the first evaporator 17 and the second evaporator 18 can be suppressed. Moreover, since the nozzle part 15a of the ejector 15 can be closed immediately after starting the cycle, the refrigerant passing sound passing through the nozzle 15a does not become annoying sound.

Further, in the ejector stop operation, the refrigerant can be reliably circulated in the cycle by the suction and discharge action of the compressor 11, so that it is difficult to return the oil mixed in the refrigerant to the compressor. be able to.

This is because, like the ejector refrigeration cycle 10 of the present embodiment, the refrigerant flow is branched upstream of the nozzle portion 15a, and one of the branched refrigerants flows into the nozzle portion 15a to be branched. This is effective in a cycle configuration in which the other refrigerant is sucked from the refrigerant suction port 21b of the ejector 15 through the throttle mechanism and the evaporator.

The reason is that in such a cycle configuration, the flow rate of the refrigerant supplied to the evaporator is likely to fluctuate depending on the suction capacity of the ejector 15, and the oil mixed in the refrigerant is difficult to return to the compressor during low-load operation or the like. Because it becomes.

In addition, the ejector module 20 of the present embodiment includes a coil spring 22c that applies a load on the side of the needle valve 22 that reduces (closes) the passage cross-sectional area of the nozzle portion 15a, and includes a connecting portion 23a of the throttle valve 23 and An axial gap is formed between the inner wall surface of the engagement hole 22 a of the needle valve 22. Further, when the connecting portion 23a of the throttle valve 23 is in contact with the contact portion 22b of the needle valve 22, the needle valve 22 and the throttle valve 23 are displaced in conjunction with each other.

According to this, when both the nozzle portion 15a and the throttle passage 20b are closed from the open state without requiring complicated control or the like, the nozzle portion 15a is closed before the throttle passage 20b. When opening both the nozzle portion 15a and the throttle passage 20b from a closed state, a configuration in which the throttle passage 20b is opened before the nozzle portion 15a can be realized.

Further, in the ejector module 20 of the present embodiment, the inlet of the nozzle portion 15a and the inlet of the throttle passage 20b are open to the swirl space 20a, and the inlet of the throttle passage 20b is on the outer peripheral side of the central axis than the inlet of the nozzle portion 15a. Is open. Furthermore, in the swirling space 20a, since the refrigerant is swirling around the central axis, high-density liquid-phase refrigerant is unevenly distributed on the outer peripheral side by the action of centrifugal force.

Therefore, the refrigerant having a relatively low dryness is supplied from the swirl space 20a to the throttle passage 20b, and the refrigerant having a relatively high dryness is supplied from the swirl space 20a to the nozzle portion 15a.

According to this, since the refrigerant having a low dryness can be supplied to the first evaporator 17 side, the refrigeration capacity of the first evaporator 17 having a refrigerant evaporation temperature lower than that of the second evaporator 18 is increased, The blown air can be sufficiently cooled. Furthermore, since the refrigerant having a high degree of dryness can be supplied to the nozzle portion 15a, the amount of recovered energy in the ejector 15 can be increased, and the energy conversion efficiency of the ejector 15 can be improved.

Here, the amount of energy recovered by the ejector applied to the refrigeration cycle apparatus is the amount of decrease in the enthalpy of the refrigerant when the refrigerant is isentropically depressurized at the nozzle portion (that is, the enthalpy of the inflowing refrigerant flowing into the nozzle portion). To the enthalpy difference obtained by subtracting the enthalpy of the injected refrigerant immediately after being injected from the nozzle portion.

Furthermore, it is known that the amount of recovered energy increases as the dryness x flowing into the nozzle portion increases. The reason is that as the dryness x flowing into the nozzle portion increases, the slope of the isentropic line on the Mollier diagram decreases.

(Second Embodiment)
In the present embodiment, as shown in FIG. 9, an ejector refrigeration cycle 10 a in which a branch portion 14, an ejector 15 having a variable nozzle portion, and a variable throttle mechanism 16 are configured separately will be described. In FIG. 9, the same or equivalent parts as those in the first embodiment are denoted by the same reference numerals. The same applies to the following drawings.

As the branching portion 14 of the ejector refrigeration cycle 10a, a centrifugal gas-liquid separator structure can be employed. Then, the refrigerant having a relatively high dryness on the turning center side is caused to flow out to the nozzle portion 15a side of the ejector 15, and the refrigerant having a relatively low dryness on the outer peripheral side is caused to flow out to the variable throttle mechanism 16 side. As the variable throttle mechanism 16 of the ejector refrigeration cycle 10a, an electric expansion valve can be adopted.

In the present embodiment, as shown in the block diagram of FIG. 10, a suction refrigerant pressure sensor 48 and a suction refrigerant temperature sensor 49 are additionally connected to the input side of the air conditioning control device 40. The suction refrigerant pressure sensor 48 is a suction pressure detection unit that detects the suction refrigerant pressure Pi of the refrigerant sucked into the refrigerant suction port 21 b of the ejector 15. The suction refrigerant temperature sensor 49 is a suction temperature detection unit that detects the suction refrigerant temperature Ti of the refrigerant sucked into the refrigerant suction port 21b.

Furthermore, in the present embodiment, since the ejector 15 and the variable throttle mechanism 16 are configured as separate bodies, each has a drive mechanism section that displaces the valve body section. Therefore, the structure which controls the action | operation of the ejector 15 among the air-conditioning control apparatuses 40 comprises the ejector control part 40b. Further, the configuration for controlling the operation of the variable aperture mechanism 16 constitutes a variable aperture control unit 40c.

Next, the operation of this embodiment in the above configuration will be described. The basic operation of the ejector refrigeration cycle 10a of this embodiment is the same as that of the first embodiment. More specifically, during normal operation, the air-conditioning control device 40 controls the variable nozzle portion of the ejector 15 so that the superheat degree of the suction refrigerant approaches a predetermined suction side reference superheat degree (1 ° C. in the present embodiment). Control the operation.

Further, during normal operation, the air conditioning control device 40 is sucked from the refrigerant suction port 21b based on the suction refrigerant pressure Pi detected by the suction refrigerant pressure sensor 48 and the suction refrigerant temperature Ti detected by the suction refrigerant temperature sensor 49. The degree of superheat of the refrigerant on the outlet side of the first evaporator 17 is calculated. Then, the operation of the variable throttle mechanism 16 is controlled so that the calculated superheat degree approaches a predetermined suction side reference superheat degree (0 ° C. in the present embodiment).

Other operations during normal operation are the same as in the first embodiment. Therefore, during normal operation, similarly to the first embodiment, it is possible to suppress a decrease in the COP of the ejector refrigeration cycle 10a even if a load change occurs.

In the ejector stop operation, the air conditioning control device 40 closes the variable nozzle portion of the ejector 15. Further, the air conditioning control device 40 controls the operation of the variable throttle mechanism 16 so that the degree of superheat of the suction refrigerant approaches the suction side reference superheat degree. Other operations during the ejector stop operation are the same as those in the first embodiment. Therefore, during the ejector stop operation, the ejector refrigeration cycle 10 can be appropriately operated as in the first embodiment.

The present disclosure is not limited to the above-described embodiment, and various modifications can be made as follows without departing from the spirit of the present disclosure.

In the above-described embodiment, the stop condition determination unit configured in the control step S1 determines that the ejector stop condition is satisfied when the temperature difference ΔT is equal to or greater than the reference temperature difference KΔT. However, the determination of the ejector stop condition in the stop condition determination unit is not limited to this.

For example, it may be determined that the ejector stop condition is satisfied when the refrigerant discharge capacity of the compressor 11 is equal to or less than a predetermined reference discharge capacity. This is because when the refrigerant discharge capacity of the compressor 11 is less than or equal to the reference discharge capacity, the operation is low load, and the oil mixed in the refrigerant is difficult to return to the compressor.

Furthermore, in a cycle that employs an electric compressor as the compressor, even if it is determined that the ejector stop condition is satisfied when the rotation speed of the electric compressor is equal to or less than a predetermined reference rotation speed. Good. In a cycle that employs a variable capacity compressor as the compressor, it may be determined that the ejector stop condition is satisfied when the discharge capacity is equal to or less than a predetermined reference capacity.

Further, when the superheat degree of the refrigerant on the outlet side of the first evaporator 17 is equal to or lower than a predetermined reference superheat degree, it may be determined that the ejector stop condition is satisfied. This is because the refrigerant cannot sufficiently absorb heat from the blown air in the first evaporator 17 during low-load operation, and the liquid-phase refrigerant may flow out of the first evaporator 17.

Alternatively, it may be determined that the ejector stop condition is satisfied when the pressure of the suction refrigerant of the compressor 11 is equal to or lower than a predetermined reference suction refrigerant pressure. This is because during low-load operation, the density of the suction refrigerant decreases, and the pressure of the suction refrigerant may greatly decrease.

Further, it may be determined that the ejector stop condition is satisfied until a predetermined reference time elapses after the cycle (that is, the compressor 11) is started. This is because when the cycle is started, the refrigerant suddenly flows into the nozzle portion 15a of the ejector 15, and the refrigerant passing sound passing through the nozzle 15a may be annoying to the user.

The ejector refrigeration cycle to which the ejector module 20 described in the first embodiment can be applied is not limited to that disclosed in the above-described embodiment.

For example, the ejector module 20 may be applied to the ejector refrigeration cycle 10b shown in the overall configuration diagram of FIG.

Specifically, the ejector refrigeration cycle 10b includes a compressor 11 that compresses and discharges a refrigerant, a radiator 12 that dissipates heat from the refrigerant discharged from the compressor 11, and a gas-liquid separator 31 that separates refrigerant gas and liquid. The decompression device 32 that decompresses the liquid-phase refrigerant separated by the gas-liquid separator 31, the first evaporator 17 that evaporates the refrigerant decompressed by the decompression device 32, and the refrigerant decompressed by the decompression unit are evaporated The second evaporator 18, and the merge section 33 that merges the gas-phase refrigerant separated by the gas-liquid separator 31 and the refrigerant that has flowed out of the second evaporator 18 to flow out to the suction side of the compressor 11. ing.

In the ejector refrigeration cycle 10b, the outlet side of the radiator 12 is connected to the high pressure inlet 21a of the ejector module 20, the refrigerant outlet side of the first evaporator 17 is connected to the refrigerant suction port 21b, and the ejector side outlet 21c is connected. The inlet side of the gas-liquid separator 31 is connected, and the refrigerant inlet side of the second evaporator 18 is connected to the throttle side outlet 21d.

Further, in the first evaporator 17 of the ejector refrigeration cycle 10b, heat exchange is performed between the low-pressure refrigerant decompressed by the decompression device 32 and the blown air blown from the first blower 17a. In the second evaporator 18, heat exchange is performed between the low-pressure refrigerant decompressed by the variable throttle mechanism 16 and the blown air blown from the second blower 18a.

In the ejector refrigeration cycle 10b, the refrigerant outlet of the junction 33 is directly connected to the suction side of the compressor 11, the refrigerant outlet of the first evaporator 17 is connected to the low pressure inlet 21e side, and the low pressure outlet 21f is sucked of refrigerant. You may connect to the port 21b.

Then, the operation of the drive mechanism unit 24 may be controlled so that the superheat degree of the refrigerant on the outlet side of the first evaporator 17 approaches the suction side reference superheat degree (0 ° C. in this embodiment). Of course, in the ejector stop operation, the operation of the drive mechanism 24 may be controlled so as to close the nozzle portion 15a of the ejector 15.

Each component device constituting the ejector refrigeration cycle 10 to 10b is not limited to the one disclosed in the above embodiment.

For example, in the above-described embodiment, an example in which an electric compressor is employed as the compressor 11 has been described. However, the compressor 11 is driven by a rotational driving force transmitted from a vehicle traveling engine via a pulley, a belt, or the like. An engine driven compressor may be employed. Furthermore, as an engine-driven compressor, the variable capacity compressor that can adjust the refrigerant discharge capacity by changing the discharge capacity, or the refrigerant discharge capacity can be adjusted by changing the operating rate of the compressor by intermittently connecting the electromagnetic clutch A fixed-capacity compressor can be employed.

In the above-described embodiment, an example in which a receiver-integrated condenser is employed as the radiator 12 has been described. Further, the radiator 12 has a supercooling unit that supercools the liquid-phase refrigerant flowing out from the receiver unit 12b. A so-called subcool condenser may be employed. In addition, a radiator 12 including only the condensing unit 12a, and a receiver (receiver) that separates the gas-liquid refrigerant flowing out of the radiator 12 and flows the separated liquid-phase refrigerant downstream. It may be adopted.

In the above-described embodiment, the example in which R134a is adopted as the refrigerant has been described, but the refrigerant is not limited to this. For example, R1234yf, R600a, R410A, R404A, R32, R407C, etc. may be adopted. Or you may employ | adopt the mixed refrigerant | coolant etc. which mixed multiple types among these refrigerant | coolants. Furthermore, a supercritical refrigeration cycle in which carbon dioxide is employed as the refrigerant and the high-pressure side refrigerant pressure is equal to or higher than the critical pressure of the refrigerant may be configured.

Further, in the ejector refrigeration cycle 10, the example in which the first evaporator 17 and the second evaporator 18 are integrally configured has been described. However, as in the ejector refrigeration cycle 10b, the first evaporator 17 and the second evaporator The vessel 18 may be configured separately. In the first evaporator 17 and the second evaporator 18, different refrigerant target fluids may be cooled in different temperature zones.

In the ejector refrigeration cycle 10a described in the second embodiment, an example is described in which an electric expansion valve is used as the variable throttle mechanism 16, but a deformable member that deforms according to the temperature and pressure of the refrigerant is used. You may employ | adopt what was comprised with the mechanical mechanism which has.

In each of the above-described embodiments, the example in which the ejector module 20 according to the present disclosure is applied to the ejector refrigeration cycles 10 to 10b mounted on a vehicle has been described, but the application of the ejector module 20 is not limited thereto. For example, the present invention may be applied to an ejector-type refrigeration cycle used in a stationary air conditioner, a cold / hot storage, or the like.

Although the present disclosure has been described based on the embodiments, it is understood that the present disclosure is not limited to the embodiments and structures. The present disclosure includes various modifications and modifications within the equivalent range. In addition, although various combinations and forms are shown in the present disclosure, other combinations and forms including only one element, more or less than them are also included in the scope and concept of the present disclosure. Is.

Claims (8)

1. An ejector module applied to an ejector refrigeration cycle (10, 10b),
   A nozzle part (15a) for injecting the refrigerant under reduced pressure;
   A decompression section (20b) for decompressing the refrigerant;
   A refrigerant suction port (21b) that sucks the refrigerant from the outside by the suction action of the jetted refrigerant jetted from the nozzle unit, and a boosting unit that boosts the mixed refrigerant of the jetted refrigerant and the sucked refrigerant sucked from the refrigerant suction port (15b) formed body part (21);
   A nozzle side valve body portion (22) for changing a passage cross-sectional area of the nozzle portion;
   A pressure reducing side valve body portion (23) for changing a passage sectional area of the pressure reducing portion;
   A drive mechanism (24) for displacing the nozzle side valve body and the pressure reducing side valve body,
   When the driving mechanism portion closes the nozzle portion and the pressure reducing portion from the opened state, the drive mechanism portion closes the nozzle portion before the pressure reducing portion, and further closes the nozzle portion and the pressure reducing portion. An ejector module that opens the decompression section before the nozzle section when opening from a closed state.
2. The body portion is formed with a swirling space (20a) for swirling the refrigerant around the central axis of the nozzle portion,
   The inlet of the nozzle part and the inlet of the throttle part are open to the swirl space,
   2. The ejector module according to claim 1, wherein an inlet of the throttle portion is opened toward an outer peripheral side of a central axis with respect to an inlet of the nozzle portion.
3. An elastic member (22c) that applies a load to the nozzle side valve body portion on the side of reducing the refrigerant passage area of the nozzle portion;
   The drive mechanism is connected to the pressure reducing valve body,
   The nozzle side valve body portion is formed with a contact portion (22b) that contacts when the pressure reducing side valve body portion is displaced,
   3. The ejector module according to claim 1, wherein the nozzle side valve body portion is displaced in conjunction with the pressure reduction side valve body portion when the pressure reduction side valve body portion is in contact with the contact portion.
4. The ejector refrigeration cycle (10) includes a compressor (11) that compresses and discharges a refrigerant, a radiator (12) that dissipates heat from the refrigerant discharged from the compressor, and a first evaporator (17) that evaporates the refrigerant. ), And a second evaporator (18) for evaporating the refrigerant and flowing it out to the suction side of the compressor,
   The outlet side of the radiator is connected to the high-pressure inlet (21a) through which the refrigerant flows into the nozzle part and the decompression part,
   A refrigerant outlet side of the first evaporator is connected to the refrigerant suction port;
   A refrigerant inlet side of the second evaporator is connected to an ejector side outlet (21c) for allowing the refrigerant to flow out from the pressure increasing unit,
   The ejector module according to any one of claims 1 to 3, wherein a refrigerant inlet side of the first evaporator is connected to a throttle-side outlet (21d) through which the refrigerant flows out from the decompression unit.
5. A compressor (11) for compressing and discharging the refrigerant;
   A radiator (12) for dissipating heat from the refrigerant discharged from the compressor;
   A branch part (14) for branching the flow of the refrigerant flowing out of the radiator;
   The refrigerant is sucked from the refrigerant suction port (21b) by the suction action of the jetted refrigerant jetted from the variable nozzle part that depressurizes one of the refrigerants branched at the branching unit, and sucked from the jetted refrigerant and the refrigerant suction port. An ejector (15) for increasing the pressure of the mixed refrigerant with the sucked refrigerant;
   A variable throttle mechanism (16) for depressurizing the other refrigerant branched at the branch portion;
   A first evaporator (17) that evaporates the refrigerant depressurized by the variable throttle mechanism and causes the refrigerant to flow toward the refrigerant suction port;
   A second evaporator (18) for evaporating the refrigerant flowing out of the ejector and flowing out to the suction side of the compressor;
   An ejector control section (40b) for controlling a passage sectional area of the variable nozzle section;
   A stop condition determination unit (S1) that determines that a predetermined ejector stop condition is satisfied,
   The ejector control unit is an ejector-type refrigeration cycle that closes the variable nozzle unit when the stop condition determining unit determines that the ejector stop condition is satisfied.
6. An evaporator temperature detector (47) for detecting temperatures of a plurality of portions of the first evaporator;
   The stop condition determination unit establishes the ejector stop condition when a temperature difference (ΔT) obtained by subtracting the minimum temperature from the maximum temperature detected by the temperature detection unit is equal to or greater than a predetermined reference temperature difference (KΔT). The ejector-type refrigeration cycle according to claim 5, wherein the ejector refrigeration cycle is determined as having been performed.
7. The ejector refrigeration according to claim 5 or 6, wherein the stop condition determining unit determines that the ejector stop condition is satisfied until a predetermined reference time elapses after the compressor is started. cycle.
8. The stop condition determination unit determines that the ejector stop condition is satisfied when the refrigerant discharge capacity of the compressor is equal to or less than a predetermined reference discharge capacity. The ejector-type refrigeration cycle according to one.

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