JP2018146140A - Ejector-type refrigeration cycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ejector-type refrigeration cycle which can properly adjust a throttle opening of a suction-side decompressor which is arranged at an upstream side of a refrigerant flow of a suction-side evaporator.SOLUTION: In a suction-side decompressor 16 which is arranged at an upstream side of a refrigerant flow of a suction-side evaporator 17 for evaporating a refrigerant and making it flow out to a refrigerant suction port 15c side of an ejector 15, when the decompressor is in a low-load operation in which a thermal load of a cycle is dropped to a preset reference load or lower, a throttle opening is changed so that the refrigerant flowing out of the suction-side evaporator 17 approximates a saturation air-phase refrigerant within a range in which the refrigerant is brought into an air/liquid two-phase state, and when the decompressor is in a normal operation or in a high-load operation at which the thermal load of the cycle is raised to the reference load or higher, the throttle opening is changed so that the refrigerant flowing out of the suction-side evaporator 17 approximates the saturation air-phase refrigerant within a range in which the refrigerant is brought into an air phase state.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an ejector-type refrigeration cycle including an ejector.

  2. Description of the Related Art Conventionally, an ejector-type refrigeration cycle that is a vapor compression 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 ejector can increase the pressure of the refrigerant sucked into the compressor to reduce the power consumption of the compressor, so the coefficient of performance (COP) of the cycle can be reduced. Can be improved.

  For example, Patent Document 1 discloses an ejector-type refrigeration cycle that includes a branch portion that branches a flow of high-pressure refrigerant that has flowed out of a radiator. In the ejector-type refrigeration cycle of Patent Document 1, one refrigerant branched at the branching portion flows into the nozzle portion of the ejector, and the other refrigerant branched at the branching portion is sucked into the suction-side evaporator via the suction-side decompression device. In the cycle configuration, the refrigerant flowing into the refrigerant and flowing out from the suction-side evaporator is sucked from the refrigerant suction port of the ejector.

  Patent Document 2 discloses an ejector-type refrigeration cycle in which a nozzle-side pressure reducing device for reducing the pressure of one refrigerant branched at the branching portion on the upstream side of the nozzle portion is added to Patent Document 1.

Japanese Patent No. 3931899 Japanese Patent No. 4600208

  By the way, in the ejector type refrigeration cycle of Patent Document 1, it is necessary to appropriately adjust the throttle opening of the suction side pressure reducing device in accordance with the load fluctuation of the cycle.

  For example, at the time of low load operation, the flow rate of the refrigerant flowing into the nozzle portion decreases, so the suction capability of the ejector decreases. If the suction capacity of the ejector decreases, it becomes impossible to allow a sufficient amount of refrigerant to flow into the suction-side evaporator, and the cooling target fluid (for example, into the air-conditioning target space) cooled by the suction-side evaporator. The temperature distribution of the blown air) is expanded. Therefore, during low load operation, it is necessary to adjust the throttle opening of the suction side pressure reducing device so as not to become unnecessarily small.

  Further, during normal operation or high load operation, sufficient refrigerant can be allowed to flow into the nozzle portion, so that the ejector can easily exhibit sufficient suction capability. However, when the refrigerant flow rate (mass flow rate) sucked from the refrigerant suction port is increased, the boosting capability of the ejector is lowered, and thus the above-described COP improvement effect cannot be obtained sufficiently. Therefore, it is necessary to adjust the throttle opening of the suction side pressure reducing device so as not to become unnecessarily large during normal operation or high load operation.

  However, the cited document 1 does not disclose a specific adjustment mode of the throttle opening of the suction side pressure reducing device.

  Further, as in Patent Document 2, in an ejector-type refrigeration cycle equipped with a nozzle-side pressure reducing device, if the throttle opening of the nozzle-side pressure reducing device changes even if the throttle opening of the suction-side pressure reducing device is appropriately adjusted, suction is performed. The optimum throttle opening of the side pressure reducing device also changes. For this reason, in an ejector-type refrigeration cycle including a nozzle-side decompression device and a suction-side decompression device, a problem of control hunting that makes it difficult for both throttle openings to converge to an appropriate value is likely to occur.

  An object of the present invention is to provide an ejector refrigeration cycle capable of appropriately adjusting the throttle opening degree of a suction side decompression device arranged on the upstream side of the refrigerant flow of the suction side evaporator.

In order to achieve the above object, the invention described in claim 1 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 downstream of the radiator. The refrigerant is sucked from the refrigerant suction port (15c) by the suction action of the jet refrigerant jetted from the nozzle portion (15a) for depressurizing the refrigerant on the side, and the mixed refrigerant of the jet refrigerant and the suction refrigerant sucked from the refrigerant suction port is The ejector (15) whose pressure is increased by the pressure increasing unit (15d), the suction side pressure reducing device (16) for reducing the pressure of the refrigerant, and the suction for evaporating the refrigerant decompressed by the suction side pressure reducing device and flowing it out to the refrigerant suction port side A side evaporator (17),
The suction-side decompression device converts the refrigerant flowing out of the suction-side evaporator into a saturated gas-phase refrigerant within a range in which it enters a gas-liquid two-phase state when the heat load of the cycle is lower than a predetermined reference load. When the throttle opening is changed so as to approach, and the heat load of the cycle is higher than the reference load, the refrigerant flowing out of the suction side evaporator approaches the saturated gas phase refrigerant in the range where the gas phase is changed. In this way, the ejector refrigeration cycle changes the throttle opening.

  According to this, when the heat load of the cycle is lower than the reference load, the refrigerant flowing out from the suction side evaporator (17) can be a gas-liquid two-phase refrigerant having a relatively high dryness. Therefore, the temperature change of the refrigerant in the suction side evaporator (17) can be suppressed, and the expansion of the temperature distribution of the cooling target fluid cooled by the suction side evaporator (17) can be suppressed.

  Further, when the heat load of the cycle is lower than the reference load, the suction refrigerant flow rate is also reduced. Therefore, even if the refrigerant sucked from the refrigerant suction port (15c) of the ejector (15) is a gas-liquid two-phase refrigerant having a relatively high dryness, the pressure increasing action in the pressure increasing part (15d) of the ejector (15) is achieved. The degree of decline is small.

  On the other hand, when the heat load of the cycle is higher than the reference load, the refrigerant flowing out from the suction side evaporator (17) can be made a gas phase refrigerant having a relatively low superheat degree. Accordingly, an unnecessary increase in the flow rate (mass flow rate) of the refrigerant sucked from the refrigerant suction port (15c) of the ejector (15) is suppressed, and the boosting action in the boosting portion (15d) of the ejector (15) is prevented. It can suppress that it falls.

  Furthermore, when the heat load of the cycle is higher than the reference load, the ejector (15) can exert a sufficient suction action to supply a sufficient amount of refrigerant to the suction side evaporator (17). Therefore, even if the refrigerant flowing out from the suction side evaporator (17) is a gas phase refrigerant, it is difficult to cause an increase in the temperature distribution of the cooling target fluid cooled by the suction side evaporator (17).

  In other words, according to the present invention, the ejector-type refrigeration cycle capable of appropriately adjusting the throttle opening of the suction side pressure reducing device (16) disposed upstream of the refrigerant flow of the suction side evaporator (17). Can be provided.

  Here, the temperature distribution of the cooling target fluid can be defined by a temperature difference between the maximum temperature and the minimum temperature of the cooling target fluid cooled by the suction side evaporator (17).

According to a fourth aspect of the present invention, there is provided a compressor (11) for compressing and discharging a refrigerant, a radiator (12) for radiating heat from the refrigerant discharged from the compressor, and reducing the pressure of the refrigerant flowing out of the radiator. The refrigerant is sucked from the refrigerant suction port (15c) by the suction action of the jet refrigerant injected from the nozzle side pressure reducing device (14) to be discharged and the nozzle portion (15a) for further reducing the pressure of the refrigerant flowing out from the nozzle side pressure reducing device. In the ejector (15) for increasing the pressure of the mixed refrigerant of the refrigerant and the suctioned refrigerant sucked from the refrigerant suction port by the pressure increasing unit (15d), the suction side pressure reducing device (16) for reducing the pressure of the refrigerant, and the suction side pressure reducing device A suction-side evaporator (17) that evaporates the decompressed refrigerant and flows it out to the refrigerant suction port side,
Nozzle side response time (RTn) required for the nozzle side pressure reducing device to change the throttle opening by a predetermined reference amount, and suction side response time (RTs) required for the suction side pressure reducing device to change the throttle opening by the reference amount ) Is an ejector type refrigeration cycle.

  According to this, since the nozzle side response time (RTn) and the suction side response time (RTs) are different, the controllable interference between the nozzle side pressure reducing device (14) and the suction side pressure reducing device (16) is suppressed. Can do. Therefore, the problem of control hunting that both the throttle openings are difficult to converge to an appropriate value is less likely to occur.

  In other words, according to the present invention, the ejector-type refrigeration cycle capable of appropriately adjusting the throttle opening of the suction side pressure reducing device (16) disposed upstream of the refrigerant flow of the suction side evaporator (17). Can be provided. Here, as the reference amount of the throttle opening, the amount of change in the passage cross-sectional area may be adopted, or the ratio when the opening when fully closed is 0% and the opening when fully opened is 100%. A change amount or the like may be adopted.

  In addition, the code | symbol in the bracket | parenthesis of each means described in this column and the claim is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

It is a whole block diagram of the ejector-type refrigerating cycle of 1st Embodiment. It is a graph which shows the temperature-pressure characteristic of the temperature sensitive medium of 1st Embodiment. It is a graph which shows the temperature distribution of the suction side evaporator with respect to the change of the superheat degree of the suction side evaporator exit side refrigerant | coolant of 1st Embodiment, and the change of the pressure | voltage rise performance of an ejector. It is a graph which shows the change of COP of an ejector type refrigerating cycle with respect to the change of the superheat degree of the suction side evaporator exit side refrigerant | coolant of 1st Embodiment. It is a whole block diagram of the ejector type refrigerating cycle of 2nd Embodiment. It is a graph which shows the change of the pressure pulsation width | variety of the suction | inhalation refrigerant | coolant with respect to the change of the suction side response time of 2nd Embodiment. It is a whole block diagram of the ejector-type refrigerating cycle of other embodiment.

(First embodiment)
1st Embodiment of this invention is described using FIGS. 1-4. The ejector-type refrigeration cycle 10 of this embodiment 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 air-conditioned. Therefore, the cooling target fluid of the ejector refrigeration cycle 10 of the present embodiment 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. A part of the refrigerating machine oil circulates in the cycle together with the refrigerant.

  In the ejector refrigeration cycle 10 shown in the overall configuration diagram of FIG. 1, a compressor 11 sucks in refrigerant, compresses it, and discharges it. 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 electric motor is a motor whose rotation speed (that is, refrigerant discharge capacity) is controlled by a control signal output from the air conditioning control device, and either an AC motor or a DC motor may be adopted. .

  The refrigerant inlet side of the radiator 12 is connected to the discharge port of the compressor 11. The radiator 12 is a heat exchanger for radiating heat by exchanging heat between the high-pressure refrigerant discharged from the compressor 11 and outside air (outside air) blown by the cooling fan 12a to dissipate the high-pressure refrigerant and cool it. The cooling fan 12a 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.

  The refrigerant outlet of the radiator 12 is connected to the inlet side of the branch portion 13. The branch part 13 branches the flow of the refrigerant that has flowed out of the radiator 12. In this embodiment, a centrifugal gas-liquid separator structure is adopted as the branching portion 13. 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 suction side pressure reducing device 16 side.

  The ejector 15 has a nozzle part 15a that decompresses and injects one of the refrigerants branched at the branching part 13, 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 nozzle portion 15a.

  In addition to this, 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 15c into pressure energy, and increases the pressure of the mixed refrigerant. Acts as a device.

  More specifically, the ejector 15 includes a nozzle portion 15a and a body portion 15b. The nozzle portion 15a is formed of a substantially cylindrical metal (in this embodiment, a stainless alloy) that gradually tapers in the direction of refrigerant flow. The nozzle part 15a is an isentropic decompression expansion of the refrigerant in the refrigerant passage formed inside.

  The refrigerant passage formed in the nozzle portion 15a includes a throat portion that reduces the passage cross-sectional area the most, and a divergent portion in which the passage cross-sectional area gradually increases from the throat toward the refrigerant injection port that injects the refrigerant. Is formed. That is, the nozzle portion 15a of the present embodiment is configured as a Laval nozzle.

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

  The body portion 15b is formed of a substantially cylindrical metal (in this embodiment, aluminum). The body portion 15b functions as a fixing member that supports and fixes the nozzle portion 15a therein and forms an outer shell of the ejector 15. More specifically, the nozzle portion 15a is fixed by press-fitting so as to be housed inside the longitudinal end of the body portion 15b. The body part 15b may be formed of resin.

  Of the outer peripheral surface of the body portion 15b, a portion corresponding to the outer peripheral side of the nozzle portion 15a is formed with a refrigerant suction port 15c provided so as to penetrate the inside and the outside and communicate with the refrigerant injection port of the nozzle portion 15a. ing. The refrigerant suction port 15c is a through hole that sucks the refrigerant that has flowed out from a suction side evaporator 17 described later into the ejector 15 by the suction action of the jet refrigerant injected from the nozzle portion 15a.

  Inside the body portion 15b is a suction passage that guides the suction refrigerant sucked from the refrigerant suction port 15c to the refrigerant injection port side of the nozzle portion 15a, and a pressure increase portion that increases the pressure by mixing the suction refrigerant and the injection refrigerant. A diffuser portion 15d is formed.

  The suction passage is formed in a space between the outer peripheral side around the tapered tip of the nozzle portion 15a and the inner peripheral side of the body portion 15b, and the refrigerant passage area of the suction passage is directed toward the refrigerant flow direction. It is gradually shrinking. As a result, the flow rate of the suction refrigerant flowing through the suction passage is gradually increased to reduce energy loss (ie, mixing loss) when the suction refrigerant and the injection refrigerant are mixed in the diffuser portion 15d.

  The diffuser portion 15d is a frustoconical refrigerant passage disposed so as to be continuous with the outlet of the suction passage. In the diffuser portion 15d, the passage cross-sectional area gradually increases toward the downstream side of the refrigerant flow. The diffuser portion 15d converts the kinetic energy of the mixed refrigerant into pressure energy by such a passage shape.

  More specifically, the cross-sectional shape of the inner peripheral wall surface of the body portion 15b that forms the diffuser portion 15d of the present embodiment is formed by combining a plurality of curves. And since the degree of spread of the refrigerant passage cross-sectional area of the diffuser portion 15d gradually increases in the refrigerant flow direction and then decreases again, the refrigerant can be increased in an isentropic manner.

  The refrigerant inlet side of the outflow side evaporator 18 is connected to the outlet of the diffuser portion 15d. The outflow side evaporator 18 heat-exchanges the refrigerant that has flowed out of the diffuser portion 15d and the blown air that is blown from the blower 18a into the vehicle interior, and cools the blown air by evaporating the refrigerant and exerting an endothermic effect. It is a heat exchanger for heat absorption.

  The blower 18a is an electric blower in which the rotation speed (that is, the amount of blown air) is controlled by a control voltage output from the air conditioning control device. Furthermore, the suction port side of the compressor 11 is connected to the refrigerant outlet side of the outflow side evaporator 18.

  Next, the suction-side decompression device 16 is a variable throttle mechanism that performs the function of decompressing the other refrigerant branched at the branching section 13 and flowing into the suction-side evaporator 17 described later. Further, the suction side pressure reducing device 16 functions as a flow rate adjusting device that adjusts the flow rate of the refrigerant flowing into the suction side evaporator 17.

  More specifically, the suction side pressure reducing device 16 includes a valve body portion 16a, a temperature sensing portion 16b, and the like. The valve body portion 16a is a metal valve body that changes the cross-sectional area of the throttle passage that depressurizes the other refrigerant branched by the branch portion 13. The temperature sensing part 16b displaces the valve body part 16a.

  The temperature sensing part 16b has a case 16c and a diaphragm 16d. The case 16c is formed of a cup-shaped (in other words, cup-shaped) metal member. The case 16c is a sealed space forming member that forms a sealed space in which a temperature sensitive medium is sealed. The temperature sensitive medium is a medium whose pressure changes according to the temperature of the refrigerant flowing out of the suction side evaporator 17.

  The diaphragm 16d is formed of a circular thin plate-shaped metal member, and forms an enclosed space together with the case 16c. The diaphragm 16d is a deformable member that deforms according to the pressure difference between the pressure of the temperature-sensitive medium and the pressure of the refrigerant that has flowed out of the suction-side evaporator 17 (that is, the pressure of the suction-side evaporator 17 outlet-side refrigerant).

  The diaphragm 16d is connected to the valve body 16a through an operating rod or the like. Therefore, the valve body 16a is displaced with the deformation of the diaphragm 16d. The diaphragm 16 d is disposed in the suction side decompression device 16 so that the surface on the opposite side of the enclosed space can come into contact with the refrigerant flowing out of the suction side evaporator 17. For this reason, the pressure of the temperature sensitive medium in the enclosed space changes according to the temperature of the refrigerant flowing out from the suction side evaporator 17.

  More specifically, when the temperature (superheat degree) of the refrigerant flowing out from the suction side evaporator 17 increases, the pressure in the enclosed space increases. As a result, the pressure difference obtained by subtracting the pressure of the refrigerant on the outlet side of the suction side evaporator 17 from the pressure of the temperature-sensitive medium increases, and the diaphragm 16d is deformed to increase the volume of the enclosed space. Along with this deformation, the valve body portion 16a is displaced to the side of enlarging the passage sectional area of the throttle passage.

  On the other hand, when the temperature (superheat degree) of the refrigerant flowing out from the suction side evaporator 17 decreases, the pressure in the enclosed space decreases. As a result, the pressure difference obtained by subtracting the pressure of the refrigerant on the outlet side of the suction side evaporator 17 from the pressure of the temperature-sensitive medium is reduced, and the diaphragm 16d is deformed to reduce the volume of the enclosed space. Along with this deformation, the valve body 16a is displaced to the side of reducing the passage cross-sectional area of the throttle passage.

  Therefore, in the suction-side decompression device 16, the valve body portion 16a can be displaced according to the degree of superheat of the suction-side evaporator 17 outlet-side refrigerant. Therefore, in the suction side pressure reducing device 16 of the present embodiment, the valve body portion 16a is set so that the superheat degree of the refrigerant on the outlet side of the suction side evaporator 17 approaches a predetermined reference superheat degree (specifically, 0 ° C.). Displace.

  Further, the suction side pressure reducing device 16 has a coil spring which is an elastic member (not shown). The coil spring applies a load on the side that reduces the cross-sectional area of the throttle passage to the valve body 16a. Therefore, the reference superheat degree mentioned above can be adjusted by changing the load by a coil spring.

  In the suction-side decompression device 16, as shown in FIG. 2, the pressure in the temperature zone lower than the predetermined reference temperature KT is higher than the saturation pressure of the refrigerant circulating in the cycle, as shown in FIG. A pressure is used in which the pressure in the temperature range higher than the temperature KT is lower than the saturation pressure of the refrigerant.

  That is, the suction side pressure reducing device 16 of the present embodiment is a so-called cross-charge type temperature expansion valve. As the temperature-sensitive medium having such characteristics, it is possible to employ a refrigerant in which an inert gas (specifically, nitrogen) is mixed with a refrigerant having a component different from that of the refrigerant circulating in the cycle.

  For this reason, in the suction side decompression device 16, when the temperature of the refrigerant on the outlet side of the suction side evaporator 17 is lower than the reference temperature KT, the suction side decompression device 16 is more restrictive than that employing a refrigerant that circulates in the cycle as the temperature sensitive medium. The passage sectional area of the passage can be enlarged. Therefore, in the suction-side decompression device 16 of the present embodiment, when the temperature of the suction-side evaporator 17 outlet-side refrigerant is lower than the reference temperature KT, the suction-side evaporator 17 outlet-side refrigerant is a gas-liquid two-phase refrigerant. It can be.

  On the other hand, in the suction side decompression device 16, when the temperature of the refrigerant on the outlet side of the suction side evaporator 17 is higher than the reference temperature KT, the throttle passage is more than that employing a refrigerant that circulates in the cycle as a temperature sensitive medium. The cross-sectional area of the passage can be reduced. Therefore, in the suction-side decompression device 16 of the present embodiment, when the temperature of the suction-side evaporator 17 outlet-side refrigerant is higher than the reference temperature KT, the suction-side evaporator 17 outlet-side refrigerant is a gas-phase refrigerant. be able to.

  Here, in FIG. 2, the temperature-pressure characteristic (that is, the saturation curve) of the refrigerant circulating in the cycle (R134a in this embodiment) is indicated by a thick broken line, and the temperature-pressure characteristic of the temperature-sensitive medium of this embodiment is shown. Indicated by a bold solid line.

  Furthermore, in this embodiment, the refrigerant | coolant evaporation temperature in the suction side evaporator 17 when the heat load of a cycle is a predetermined reference load is set as the reference temperature KT. The reference load is during low load operation when the cycle thermal load is lower than the reference load, and during normal operation when the cycle thermal load is higher than the reference load. Or it is a reference value for judging that it is at the time of high load operation.

  For this reason, the suction-side decompression device 16 is basically configured so that the superheat degree of the suction-side evaporator 17 outlet-side refrigerant approaches 0 ° C. (that is, the suction-side evaporator 17 outlet-side refrigerant becomes a saturated gas-phase refrigerant). The valve body part 16a is displaced so that it may approach.

  When the heat load of the cycle becomes lower than the reference load and the temperature of the suction side evaporator 17 outlet side refrigerant becomes lower than the reference temperature KT, the suction side evaporator 17 outlet side refrigerant is in a gas-liquid two-phase state. In such a range, the valve body 16a is displaced so that the degree of superheat approaches 0 ° C. For this reason, when the heat load of the cycle is lower than the reference load, the refrigerant flowing out from the suction side evaporator 17 becomes a gas-liquid two-phase refrigerant having a relatively high dryness.

  Further, when the heat load of the cycle becomes higher than the reference load and the temperature of the suction side evaporator 17 outlet side refrigerant becomes higher than the reference temperature KT, the suction side evaporator 17 outlet side refrigerant enters a gas phase state. Within a range, the valve body 16a is displaced so that the degree of superheat approaches 0 ° C. For this reason, when the heat load of the cycle is higher than the reference load, the refrigerant flowing out of the suction side evaporator 17 becomes a gas phase refrigerant having a relatively low degree of superheat.

  The refrigerant inlet side of the suction side evaporator 17 is connected to the outlet of the suction side decompression device 16. The suction-side evaporator 17 exchanges heat between the blown air that has passed through the outflow-side evaporator 18 and the low-pressure refrigerant decompressed by the suction-side decompression device 16, and evaporates the low-pressure refrigerant to exert a heat absorption effect. An endothermic heat exchanger that cools blown air.

  The refrigerant outlet of the suction side evaporator 17 is connected to the refrigerant suction port 15 c side of the ejector 15 through a refrigerant passage communicating with the temperature sensing part 16 b formed in the suction side pressure reducing device 16.

  Moreover, the suction side evaporator 17 and the outflow side evaporator 18 of this embodiment are integrally comprised. Specifically, each of the suction-side evaporator 17 and the outflow-side 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 suction-side evaporator 17 and the outflow-side evaporator 18 are integrated by forming the collecting / distributing tank of the suction-side evaporator 17 and the outflow-side evaporator 18 with the same member. At this time, in this embodiment, the suction-side evaporator 17 and the outflow-side evaporator 18 are changed to the blown air flow so that the outflow-side evaporator 18 is arranged upstream of the blown air flow with respect to the suction-side 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 of the present embodiment will be described. An air conditioning control device (not shown) is composed of a well-known microcomputer including a CPU, ROM, RAM, etc. 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 the various controlled devices 11, 12a, 18a and the like is controlled.

  In addition, the air conditioning control device includes an inside air temperature sensor that detects the temperature inside the vehicle, an outside air temperature sensor that detects the outside air temperature, a solar radiation sensor that detects the amount of solar radiation in the vehicle interior, and the temperature of the air blown from the suction-side evaporator 17. Sensor groups such as an evaporator temperature sensor for detecting (evaporator temperature) are connected, and detection values of these air conditioning sensor groups are input.

  Further, an operation panel (not shown) is connected to the input side of the air conditioning control device, and operation signals from various operation switches provided on the operation panel are input to the air conditioning control device. As various operation switches provided on the operation panel, an air conditioning operation switch that requests air conditioning, a vehicle interior temperature setting switch that sets the vehicle interior temperature, and the like are provided.

  Note that the air conditioning control device of the present embodiment is configured such that a control unit that controls the operation of various control target devices connected to the output side is integrally configured. A configuration (hardware and software) for controlling the operation of the device constitutes a control unit of each control target device. For example, the configuration for controlling the operation of the compressor 11 constitutes a discharge capacity control means.

  Next, the operation of the ejector refrigeration cycle 10 of the present embodiment having the above configuration will be described. When the air conditioning operation switch on the operation panel is turned on (ON), the air conditioning control device operates the compressor 11, the cooling fan 12a, the blower 18a, and the like.

  Thereby, the compressor 11 sucks the refrigerant, compresses it, and discharges it. The high-temperature and high-pressure refrigerant discharged from the compressor 11 flows into the radiator 12. The refrigerant flowing into the radiator 12 exchanges heat with the outside air blown from the cooling fan 12a, and is cooled and condensed. The flow of the refrigerant flowing out of the radiator 12 is branched at the branching section 13.

  One refrigerant branched by the branching portion 13 flows into the nozzle portion 15a of the ejector 15 and is decompressed in an isentropic manner and is injected. And the refrigerant | coolant which flowed out from the suction side evaporator 17 is attracted | sucked from the refrigerant | coolant suction port 15c by the suction effect | action of an injection refrigerant | coolant.

  The injection refrigerant injected from the nozzle portion 15a and the suction refrigerant sucked from the refrigerant suction port 15c flow into the diffuser portion 15d. In the diffuser portion 15d, 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 by the diffuser portion 15d flows into the outflow evaporator 18.

  The refrigerant flowing into the outflow side 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 outflow side evaporator 18 is sucked into the compressor 11 and compressed again.

  On the other hand, the other refrigerant branched at the branching portion 13 flows into the suction-side decompression device 16 and is decompressed in an isenthalpy manner. At this time, in the suction side decompression device 16, the throttle opening is adjusted so that the superheat degree of the refrigerant on the outlet side of the suction side evaporator 17 approaches 0 ° C. as described above. The refrigerant depressurized by the suction side decompression device 16 flows into the suction side evaporator 17.

  The refrigerant that has flowed into the suction side evaporator 17 absorbs heat from the blown air that has passed through the outflow side evaporator 18 and evaporates. Thereby, the blast air after passing the outflow side evaporator 18 is further cooled. The refrigerant that has flowed out of the suction side evaporator 17 is sucked from the refrigerant suction port 15c.

  As described above, according to the ejector refrigeration cycle 10 of the present embodiment, the blown air blown into the vehicle compartment can be cooled by the suction side evaporator 17 and the outflow side evaporator 18.

  Further, in the ejector refrigeration cycle 10 of the present embodiment, the refrigerant on the downstream side of the outflow side evaporator 18, that is, the refrigerant whose pressure is increased by the diffuser portion 15 d 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.

  In the ejector refrigeration cycle 10 of the present embodiment, the refrigerant evaporation pressure in the outflow side evaporator 18 is set to the refrigerant pressure increased by the diffuser unit 15d, and the refrigerant evaporation pressure in the suction side evaporator 17 is set by the nozzle unit 15a. A low refrigerant pressure immediately after depressurization can be achieved. 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, in the ejector type refrigeration cycle 10 of the present embodiment, a cross-charge type temperature expansion valve is adopted as the suction side decompression device 16 so that the superheat degree of the suction side evaporator 17 outlet side refrigerant approaches 0 ° C. Further, the throttle opening degree of the suction side pressure reducing device 16 is changed.

  According to this, it is possible to appropriately change the throttle opening of the suction-side decompression device 16, and it is possible to suppress the expansion of the temperature distribution of the blown air cooled by the suction-side evaporator 17, and to eject the ejector. It is possible to suppress a decrease in the boosting action in the 15 diffuser portions 15d. Here, the temperature distribution can be defined by a temperature difference ΔT between the highest temperature and the lowest temperature of the blown air cooled by the suction side evaporator 17 or the like.

  This will be described in more detail with reference to FIGS. First, as shown by the thick broken line in FIG. 3, the temperature distribution of the blown air cooled by the suction-side evaporator 17 increases as the degree of superheat of the suction-side evaporator 17 outlet-side refrigerant increases (in other words, Then, the temperature difference ΔT increases). If the temperature distribution is enlarged, the cooling capacity Q of the blown air is lowered, so that the COP tends to be lowered.

  Here, the cooling capacity Q of the blown air is obtained by adding the refrigerant mass flow rate G to the enthalpy difference ΔH obtained by subtracting the enthalpy of the inlet side refrigerant from the enthalpy of the outlet side refrigerant of the suction side evaporator 17 (Q = ΔH × G).

  On the other hand, since the refrigerant flow rate (mass flow rate) sucked from the refrigerant suction port increases as the degree of superheat of the refrigerant on the outlet side of the suction side evaporator 17 decreases, the boosting capability of the ejector decreases. If the boosting capability of the ejector is reduced, the power consumption of the compressor 11 is increased, so that the COP tends to decrease.

  Therefore, in order to bring the COP close to the maximum value without causing an increase in the temperature distribution of the blown air cooled by the suction side evaporator 17, as shown in FIG. It is desirable that the degree of superheat is 0 ° C.

  However, in actuality, regardless of the load fluctuation of the ejector refrigeration cycle 10, the superheat degree of the suction side evaporator 17 outlet side refrigerant is set to 0 ° C., that is, the suction side evaporator 17 outlet side refrigerant is changed to a saturated gas phase refrigerant. It is difficult to maintain.

  On the other hand, in the ejector refrigeration cycle 10 of this embodiment, the refrigerant flowing out of the suction side evaporator 17 is relatively dry when the cycle heat load is lower than the reference load. It can be a two-phase refrigerant. According to this, the temperature change of the refrigerant | coolant in the suction side evaporator 17 can be suppressed, and expansion of the temperature distribution of the ventilation air cooled with the suction side evaporator 17 can be suppressed.

  Furthermore, since the flow rate of the suction refrigerant is originally reduced during the low load operation, even if the refrigerant sucked from the refrigerant suction port 15c is a gas-liquid two-phase refrigerant having a relatively high dryness, the pressure increasing action in the diffuser portion 15d. The degree of decline is small.

  On the other hand, during a normal operation or a high load operation in which the heat load of the cycle is higher than the reference load, the refrigerant that has flowed out of the suction-side evaporator 17 can be a gas-phase refrigerant with a relatively low superheat degree. Therefore, it is possible to suppress an unnecessary increase in the flow rate (mass flow rate) of the refrigerant sucked from the refrigerant suction port 15c, and it is possible to prevent the pressure increasing action in the diffuser portion 15d from being lowered.

  Further, at the time of normal operation or high load operation, the ejector 15 can exert a sufficient suction action to supply a sufficient amount of refrigerant to the suction side evaporator 17. Therefore, even if the refrigerant on the outlet side of the suction side evaporator 17 is a gas phase refrigerant, the temperature distribution of the blown air cooled by the suction side evaporator 17 is hardly increased.

  That is, according to the ejector refrigeration cycle 10 of the present embodiment, the throttle opening degree of the suction-side decompression device 16 can be adjusted appropriately. And while being able to suppress the expansion of the temperature distribution of the ventilation air cooled with the suction side evaporator 17, the fall of the pressure | voltage rise effect in the diffuser part 15d of the ejector 15 can be suppressed.

  In the ejector refrigeration cycle 10 of the present embodiment, a cross-charge type temperature expansion valve is employed as the suction side pressure reducing device 16.

  Therefore, during low load operation without complicated control or the like, the superheat degree approaches 0 ° C. in the range where the refrigerant on the outlet side of the suction evaporator 17 is in a gas-liquid two-phase state (that is, saturated gas phase refrigerant). The throttle opening is changed so that the superheat degree approaches 0 ° C. in the range where the refrigerant on the outlet side of the suction side evaporator 17 is in the gas phase state during normal operation or high load operation (ie, saturation). The throttle opening can be changed (to approach the gas phase refrigerant).

  Moreover, in the structure which arrange | positions the suction side evaporator 17 in the air flow downstream of the outflow side evaporator 18 like the ejector type refrigeration cycle 10 of this embodiment, the ventilation air cooled by the suction side evaporator 17 is arranged. By suppressing the temperature distribution, the temperature distribution of the blown air can be suppressed as the ejector refrigeration cycle 10 as a whole.

  Further, as in the ejector type refrigeration cycle 10 of the present embodiment, the refrigerant flow is branched upstream of the nozzle portion 15a, and one branched refrigerant flows into the nozzle portion 15a, and the other branched In the cycle configuration in which the refrigerant is sucked into the ejector 15 via an evaporator or the like (in this embodiment, the suction side evaporator 17), the flow rate of the refrigerant supplied to the suction side evaporator 17 varies depending on the suction capability of the ejector 15. Cheap. Therefore, it is effective to reliably supply the refrigerant to the suction side evaporator 17 during the low load operation and to suppress the temperature distribution of the blown air.

(Second Embodiment)
In the present embodiment, an example will be described in which a nozzle side pressure reducing device 14 is added to the first embodiment as shown in the overall configuration diagram of FIG. The nozzle side pressure reducing device 14 is a variable throttle mechanism that performs a function of reducing the pressure of the refrigerant branched by the branch portion 13 on the upstream side of the nozzle portion 15a. Further, the nozzle side pressure reducing device 14 functions as a flow rate adjusting device that adjusts the flow rate of the refrigerant flowing into the nozzle portion 15a.

  The basic configuration of the nozzle side pressure reducing device 14 is a temperature type expansion valve similar to the suction side pressure reducing device 16 described in the first embodiment. Accordingly, the nozzle side pressure reducing device 14 has the same valve body portion 14a and temperature sensitive portion 14b as the suction side pressure reducing device 16. In the nozzle-side decompression device 14, the superheat degree of the outlet-side evaporator 18 outlet-side refrigerant (that is, the compressor 11 suction refrigerant) approaches a predetermined nozzle-side reference superheat degree (specifically, 1 ° C.) The valve body part 14a is displaced.

  The nozzle-side pressure reducing device 14 is not limited to a cross-charge type temperature expansion valve, but is a so-called normal in which the curve drawn by the temperature-pressure characteristics of the temperature-sensitive medium is substantially parallel to the saturation curve of the refrigerant circulating in the cycle. A charge-type temperature expansion valve may be used.

  Furthermore, the suction-side decompression device 16 of this embodiment has a heat transfer suppressing member 16e that suppresses the temperature of the refrigerant flowing out of the suction-side evaporator 17 from being transmitted to the temperature-sensitive medium in the enclosed space. . More specifically, the heat transfer suppressing member 16e is a resin member or a rubber member disposed in a heat transfer path from the refrigerant to the temperature sensitive medium.

  Thereby, in this embodiment, the nozzle side response time RTn required for the nozzle side pressure reducing device 14 to change the throttle opening by the reference amount, and the suction required for the suction side pressure reducing device 16 to change the throttle opening by the reference amount. The side response time RTs is set to have a different value. More specifically, the nozzle side response time RTn is set to be shorter than the suction side response time RTs.

  Here, as the reference amount in the present embodiment, an opening degree change amount is adopted in which the opening degree of each decompression device is changed from 0% (ie, fully closed) to 100% (ie, fully opened). Accordingly, the nozzle side response time RTn is the time required for the nozzle side pressure reducing device 14 to change from the fully closed state to the fully opened state, and the suction side response time RTs is the time from the fully closed state to the fully opened state. This is the time it takes to become.

  Other configurations and operations of the ejector refrigeration cycle 10 are the same as those in the first embodiment. Therefore, according to the ejector type refrigeration cycle 10 of the present embodiment, as in the first embodiment, the expansion of the temperature distribution of the blown air cooled by the suction side evaporator 17 can be suppressed, and the ejector 15 It is possible to improve the COP of the cycle by suppressing a decrease in the boosting action in the diffuser portion 15d.

  Furthermore, since the nozzle-side pressure reducing device 14 displaces the valve body portion 14a so that the superheat degree of the refrigerant sucked by the compressor 11 approaches the nozzle-side reference superheat degree, liquid compression of the compressor 11 can be reliably suppressed. .

  By the way, in the cycle having two variable throttle mechanisms of the nozzle side pressure reducing device 14 and the suction side pressure reducing device 16 as in the ejector refrigeration cycle 10 of the present embodiment, the throttle opening degree of the suction side pressure reducing device 16 is appropriately adjusted. Even if it tries to do, if the throttle opening of the nozzle side pressure reducing device 14 changes, the optimum throttle opening of the suction side pressure reducing device 16 also changes. For this reason, a problem of control hunting that makes it difficult for both throttle openings to converge to an appropriate value is likely to occur.

  On the other hand, in the ejector refrigeration cycle 10 of the present embodiment, the nozzle side response time RTn and the suction side response time RTs are different, so that as shown in FIG. 6, the nozzle side pressure reducing device 14 and the suction side pressure reducing device It is easy to suppress the control interference with 16. Therefore, the problem of control hunting hardly occurs.

  Here, FIG. 6 is a graph for explaining the relationship between the responsiveness of the nozzle side pressure reducing device 14 and the suction side pressure reducing device 16 and control hunting. In FIG. 6, as a parameter indicating the magnitude of the control hunting, the fluctuation width of the pressure of the refrigerant sucked into the compressor 11 (that is, the pulsation width per unit time) is adopted.

  As is apparent from FIG. 6, when the suction side response time RTs coincides with the nozzle side response time RTn, the pulsation width of the suction refrigerant pressure has a peak value (that is, a maximum value). Accordingly, as in the ejector refrigeration cycle 10 of the present embodiment, the problem of control hunting can be suppressed by setting the nozzle side response time RTn and the suction side response time RTs to different values. .

  In the present embodiment, the nozzle side response time RTn is shorter than the suction side response time RTs. Therefore, the flow rate of the refrigerant supplied to the nozzle portion 15a of the ejector 15 can be quickly changed. According to this, the suction capability and the pressure increase capability of the ejector 15 can be quickly stabilized, and the cooling capability of the blown air as the entire ejector refrigeration cycle 10 can be stabilized.

  Further, as described in the first embodiment, the refrigerant flow is branched upstream of the refrigerant flow from the nozzle portion 15a, and one of the branched refrigerant flows into the nozzle portion 15a. In the cycle configuration in which the ejector 15 is sucked through the throttle mechanism and the evaporator (suction side evaporator 17 in this embodiment), the flow rate of the refrigerant supplied to the suction side evaporator 17 is likely to vary depending on the suction capability of the ejector 15. .

  Therefore, the ability to quickly stabilize the suction capability and the pressure increase capability of the ejector 15 is effective for stabilizing the cooling capability of the blown air in the ejector refrigeration cycle 10 as a whole.

  Further, in the ejector refrigeration cycle 10 of the present embodiment, temperature-type expansion valves having basically the same configuration are employed as the nozzle-side decompressor 14 and the suction-side decompressor 16. Therefore, by providing the heat transfer suppressing member 16e in the suction side pressure reducing device 16, the nozzle side response time RTn and the suction side response time RTs can be set to different values very easily without requiring complicated control.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and can be variously modified as follows without departing from the spirit of the present invention.

  (1) In the first and second embodiments described above, an example in which a cross-charge type temperature expansion valve is employed as the suction side pressure reducing device 16 has been described. However, the control output from the air conditioning control device as the suction side pressure reducing device. An electric expansion valve whose operation is controlled by a signal may be employed.

  In this case, a temperature detection unit that detects the temperature of the refrigerant that has flowed out of the suction side evaporator 17 and a pressure detection unit that detects the pressure may be added. And based on the detection value of these detection parts, you may make it change a throttle opening so that the suction side evaporator 17 exit side refrigerant | coolant may approach a saturated gaseous-phase refrigerant | coolant similarly to 1st Embodiment.

  Here, the temperature and pressure of the refrigerant flowing out from the suction side evaporator 17 are constant within a range where the refrigerant flowing out from the suction side evaporator is in a gas-liquid two-phase state. Therefore, in the range in which the refrigerant flowing out from the suction side evaporator is in a gas-liquid two-phase state, the refrigerant is stored in advance in the air conditioning control device based on the refrigerant discharge capacity (the rotation speed in the first embodiment) of the compressor 11. The throttle opening may be changed with reference to the control map.

  In the second embodiment described above, an example in which a temperature type expansion valve is employed as the nozzle side pressure reducing device 14 has been described. However, the electric expansion that is controlled by a control signal output from the air conditioning control device as the nozzle side pressure reducing device. A valve may be employed.

  In this case, a temperature detection unit that detects the temperature of refrigerant sucked into the compressor 11 and a pressure detection unit that detects pressure may be added. Based on the detection values of these detectors, the throttle opening is changed so that the superheat degree of the suction refrigerant approaches the nozzle side reference superheat degree (specifically, 1 ° C.), as in the second embodiment. You may make it make it.

  At this time, the operation of the suction side pressure reducing device 16 and the nozzle side pressure reducing device 14 is controlled in the same manner as in the second embodiment so that the air conditioning control device changes the suction side response time RTs and the nozzle side response time RTn. The effect of can be obtained.

  (2) In the above-described second embodiment, the example in which the nozzle side response time RTn is set to be shorter than the suction side response time RTs has been described. Of course, the suction side response time RTs is the nozzle side response time. Even if it is set to be shorter than RTn, the problem of control hunting can be suppressed. In this case, a heat transfer suppressing member that suppresses the temperature of the refrigerant sucked into the compressor 11 from being transmitted to the temperature-sensitive medium in the enclosed space may be added to the nozzle-side pressure reducing device 14.

  (3) The ejector refrigeration cycle according to the present invention is not limited to the one having the cycle configuration described in the above-described embodiment.

  For example, as shown in FIG. 7, an intermediate pressure decompression device 19 may be added to the ejector refrigeration cycle 10 to decompress the refrigerant flowing out of the radiator 12 until it becomes an intermediate pressure refrigerant. As such an intermediate pressure reducing device 19, a temperature type expansion valve that changes the throttle opening so that the superheat degree of the refrigerant sucked by the compressor 11 approaches the reference superheat degree (specifically, 1 ° C.) is adopted. Alternatively, an electric expansion valve that changes the throttle opening similarly may be employed.

  According to this, the refrigerant in a gas-liquid mixed state in which the pressure is reduced by the intermediate pressure reducing device 19 and the gas-phase refrigerant and the liquid-phase refrigerant are homogeneously mixed can be flowed into the branch portion 13. Therefore, the fluctuation of the flow rate ratio of the refrigerant flow rate branched at the branching portion 13 is suppressed when the gas phase refrigerant and the liquid-phase refrigerant are unevenly distributed to the branching portion 13 and the refrigerant mixed inhomogeneously is introduced. Can do.

  The ejector-type refrigeration cycle 10 includes a low-pressure side gas-liquid separator that stores the excess liquid-phase refrigerant separated by separating the gas-liquid refrigerant flowing out of the diffuser portion 15d. Even if it has a cycle configuration in which the liquid-phase refrigerant flowing out from the low-pressure side gas-liquid separator is decompressed, and the suction side of the compressor 11 is connected to the gas-phase refrigerant outlet of the low-pressure side gas-liquid separator. Good.

  (4) Each component apparatus which comprises the ejector type refrigerating cycle 10 is not limited to what was disclosed by the above-mentioned 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.

  Moreover, in the above-mentioned embodiment, although the detailed structure of the heat radiator 12 is not mentioned, the receiver integrated condenser which has the receiver part (in other words, liquid receiver) which stores the condensed refrigerant | coolant as the heat radiator 12. FIG. May be adopted. Furthermore, you may employ | adopt what is called a subcool type | mold condenser comprised including the supercooling part which supercools the liquid-phase refrigerant | coolant which flowed out from the receiver part.

  Moreover, although the example which employ | adopted the thing of the gas-liquid separation structure as the branch part 13 was demonstrated in the above-mentioned embodiment, the branch part 13 is not limited to this. For example, as the branch part 13, you may employ | adopt the thing of the three-way joint structure which has three inflow / outflow ports. One of the three inlets and outlets may be a refrigerant inlet and the remaining two may be refrigerant outlets.

  In the above-described embodiment, the example in which the suction side evaporator 17 and the outflow side evaporator 18 are integrally configured has been described. However, the suction side evaporator 17 and the outflow side evaporator 18 are configured separately. Also good. Then, different refrigerant target fluids may be cooled in different temperature zones in the suction side evaporator 17 and the outflow side evaporator 18.

  Moreover, although the above-mentioned embodiment demonstrated the example which employ | adopted R134a as a refrigerant | coolant, a refrigerant | coolant 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.

  (5) In each above-mentioned embodiment, although ejector type refrigerating cycle 10 concerning the present invention was applied to a vehicle air conditioner, application of ejector type refrigerating cycle 10 is not limited to this. For example, the present invention may be applied to stationary air conditioners, cold storages, other cooling and heating devices, and the like.

DESCRIPTION OF SYMBOLS 10 Ejector-type refrigeration cycle 12 Radiator 14 Nozzle side decompression device 15 Ejector 15a Nozzle part 15c Refrigerant suction port 15d Diffuser part 16 Suction side decompression device 17 Suction side evaporator 18 Outflow side evaporator

Claims (8)

A compressor (11) for compressing and discharging the refrigerant;
A radiator (12) for dissipating heat from the refrigerant discharged from the compressor;
The refrigerant sucked from the refrigerant suction port (15c) by the suction action of the jet refrigerant injected from the nozzle portion (15a) for depressurizing the refrigerant on the downstream side of the radiator, and sucked from the jet refrigerant and the refrigerant suction port An ejector (15) for increasing the pressure of the refrigerant mixed with the refrigerant in the pressure increasing section (15d);
A suction side decompression device (16) for decompressing the refrigerant;
A suction-side evaporator (17) that evaporates the refrigerant decompressed by the suction-side decompression device and causes the refrigerant to flow out to the refrigerant suction port side,
The suction side decompression device is a saturated gas phase within a range in which the refrigerant flowing out of the suction side evaporator is in a gas-liquid two-phase state when the heat load of the cycle is lower than a predetermined reference load. When the throttle opening is changed so as to approach the refrigerant, and the heat load of the cycle is higher than the reference load, the refrigerant flowing out of the suction-side evaporator is saturated in the range where the gas phase is changed. Ejector-type refrigeration cycle that changes the throttle opening to approach the phase refrigerant. The suction-side decompression device includes a sealed space forming member (16c) that forms a sealed space in which a temperature-sensitive medium whose pressure changes according to the temperature of the suction-side evaporator outlet-side refrigerant, and the pressure of the temperature-sensitive medium. And a deformation member (16d) that deforms according to a pressure difference between the suction side evaporator outlet side refrigerant pressure and
As the temperature sensitive medium, the pressure in a temperature zone lower than a predetermined reference temperature (TK) is higher than the saturation pressure of the refrigerant circulating in the cycle, and the pressure in the temperature zone higher than the reference temperature circulates in the cycle. The ejector-type refrigeration cycle according to claim 1, wherein a refrigerant having a pressure lower than a saturation pressure of the refrigerant is employed. A branch portion (13) for branching the flow of the refrigerant downstream of the radiator,
The nozzle portion depressurizes one refrigerant branched at the branch portion,
The ejector-type refrigeration cycle according to claim 1 or 2, wherein the suction-side decompression device decompresses the other refrigerant branched at the branch portion. A compressor (11) for compressing and discharging the refrigerant;
A radiator (12) for dissipating heat from the refrigerant discharged from the compressor;
A nozzle side decompression device (14) for decompressing the refrigerant flowing out of the radiator;
The refrigerant sucked from the refrigerant suction port (15c) is sucked from the refrigerant suction port (15c) by the suction action of the jet refrigerant injected from the nozzle part (15a) for further decompressing the refrigerant flowing out from the nozzle side decompression device, and sucked from the jet refrigerant and the refrigerant suction port. An ejector (15) for increasing the pressure of the mixed refrigerant with the suctioned refrigerant, which is increased by the pressure increasing section (15d);
A suction side decompression device (16) for decompressing the refrigerant;
A suction-side evaporator (17) that evaporates the refrigerant decompressed by the suction-side decompression device and causes the refrigerant to flow out to the refrigerant suction port side,
Nozzle side response time (RTn) required for the nozzle side pressure reducing device to change the throttle opening by a predetermined reference amount and suction side response time required for the suction side pressure reducing device to change the throttle opening by the reference amount Ejector refrigeration cycle with different (RTs).   The ejector refrigeration cycle according to claim 4, wherein the nozzle side response time (RTn) is shorter than the suction side response time (RTs). The suction-side decompression device includes a sealed space forming member (16c) that forms a sealed space in which a temperature-sensitive medium whose pressure changes according to the temperature of the suction-side evaporator outlet-side refrigerant, and the pressure of the temperature-sensitive medium. And a deformation member (16d) that deforms according to a pressure difference between the suction side evaporator outlet side refrigerant pressure and
Furthermore, the said suction side decompression device has the heat transfer suppression member (16e) which suppresses that the temperature of the said suction side evaporator exit side refrigerant | coolant is transmitted to the said temperature sensitive medium. Ejector refrigeration cycle. A branch portion (13) for branching the flow of the refrigerant downstream of the radiator,
The nozzle side decompression device is for decompressing one of the refrigerants branched at the branch part,
The ejector-type refrigeration cycle according to any one of claims 4 to 6, wherein the suction-side decompression device decompresses the other refrigerant branched at the branch portion.   The ejector-type refrigeration cycle according to claim 3 or 7, further comprising an intermediate pressure decompression device (19) that decompresses the refrigerant flowing out of the radiator to an intermediate pressure refrigerant and flows the refrigerant to an inlet side of the branch portion.

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