JP6582843B2 - Refrigeration cycle equipment - Google Patents

Description

  The present invention relates to a refrigeration cycle apparatus including a plurality of heat exchangers that evaporate refrigerant in different temperature zones.

  Conventionally, Patent Document 1 discloses a refrigeration cycle apparatus including a plurality of heat exchangers (that is, evaporators) that evaporate refrigerant in different temperature zones. The refrigeration cycle apparatus of Patent Document 1 is applied to an air conditioner for a vehicle. As a heat exchanger for evaporating a refrigerant, an indoor evaporator for exchanging heat between the refrigerant and blown air blown into the vehicle interior, and the refrigerant And an outdoor heat exchanger for exchanging heat with the outside air.

  Moreover, in the refrigeration cycle apparatus of patent document 1, when performing dehumidification heating of a vehicle interior, it switches to the refrigerant circuit which connects an indoor evaporator and an outdoor heat exchanger in parallel with respect to a refrigerant | coolant flow. In the indoor evaporator, the refrigerant is evaporated at a temperature at which frost formation does not occur (that is, a temperature higher than 0 ° C.), and in the outdoor heat exchanger, the temperature is lower than the outside air temperature (generally, in the indoor evaporator). The refrigerant is evaporated at a temperature lower than the refrigerant evaporation temperature.

  Thus, the blower air is cooled and dehumidified by the indoor evaporator, and the heat for reheating the cooled blown air is absorbed by the refrigerant in the outdoor heat exchanger.

  Furthermore, the refrigeration cycle apparatus of Patent Document 1 includes a constant pressure adjusting valve for maintaining the refrigerant pressure in the indoor evaporation at a predetermined value or higher (specifically, 0 ° C. or higher). The constant pressure regulating valve is arranged on the downstream side of the refrigerant flow of the indoor evaporator, and when performing dehumidification heating in the vehicle interior, the pressure of the refrigerant flowing out of the indoor evaporator is set to the pressure of the refrigerant flowing out of the outdoor heat exchanger. Depressurize until equivalent. The refrigerant depressurized by the constant pressure regulating valve joins with the refrigerant flowing out of the outdoor heat exchanger and is sucked into the compressor.

JP 2012-225637 A

  By the way, when the outdoor temperature is low in winter (for example, when the outdoor temperature is −10 ° C. or lower), the refrigerant evaporation pressure in the outdoor heat exchanger is greatly reduced. Furthermore, as in the refrigeration cycle apparatus of Patent Document 1, in the cycle configuration in which the pressure of the refrigerant flowing out of the indoor evaporator is reduced until it becomes equal to the pressure of the refrigerant flowing out of the outdoor heat exchanger with a constant pressure regulating valve, The pressure of the refrigerant sucked into the compressor is also greatly reduced.

  When the pressure of the suction refrigerant is thus reduced, the density of the suction refrigerant is lowered, and the volume efficiency of the compressor is lowered. As a result, the coefficient of performance (COP) as the entire refrigeration cycle apparatus is reduced. In addition, as the density of the suction refrigerant decreases, the temperature rise when the refrigerant is adiabatically compressed by the compressor increases, so the temperature of the discharged refrigerant rises abnormally and adversely affects the durable life of the compressor. It may also affect you.

  An object of this invention is to suppress the fall of the coefficient of performance of a refrigerating-cycle apparatus provided with the several heat exchanger which evaporates a refrigerant | coolant in a different temperature range in view of the said point.

The present invention has been devised to achieve the above object, and in the invention according to claim 1, a refrigeration cycle apparatus applied to an air conditioner that adjusts the temperature of the blown air blown into the air-conditioning target space. Because
A compressor (11) that compresses and discharges the refrigerant, a radiator (12) that radiates the refrigerant discharged from the compressor (11), and a branching portion that branches the flow of the refrigerant that flows out of the radiator (12) (13), a first pressure reducing device (14) that depressurizes one refrigerant branched in the branching portion (13), and a second pressure reducing device that depressurizes the other refrigerant branched in the branching portion (13). (17), the indoor evaporator (15) that heat-exchanges the refrigerant decompressed by the first decompression device (14) with the blown air, and the refrigerant decompressed by the second decompression device (17). An outdoor heat exchanger (18) that exchanges heat with outside air to evaporate, a high-pressure side refrigerant that flows through a refrigerant flow path from the outlet side of the radiator (12) to the inlet side of the branch portion (13), and the first pressure reducing device An internal heat exchanger (19) for exchanging heat with the low-pressure side refrigerant decompressed in (14); Internal heat exchanger (19) an outdoor heat exchanger from the refrigerant suction port (16a) by suction action of the high velocity injection refrigerant jetted from the nozzle portion (161) for decompressing the outflow was low-pressure side refrigerant from (18) downstream An ejector (16) having a booster (16c) that sucks the refrigerant and mixes the injected refrigerant and the sucked refrigerant sucked from the refrigerant suction port (16a) to increase the pressure;
Furthermore, a bypass passage (20) for guiding the refrigerant flowing out from the first decompression device (14) to the inlet side of the internal heat exchanger (19), bypassing the indoor evaporator (15), and the bypass passage (20) An opening and closing device (21) for opening and closing
The refrigerant outlet side of the pressure increasing part (16c) is connected to the suction port side of the compressor (11) .

According to this, when the opening / closing device (21) closes the bypass passage (20), the refrigerant depressurized by the first decompression device (14) is evaporated by the indoor evaporator (15), and the second since Ru evaporated refrigerant decompressed by pressure reducing device (17) in the outdoor heat exchanger (18), it can be evaporated refrigerant at different temperature zones by a plurality of heat exchanger functioning as an evaporator.

  Furthermore, since the ejector (16) is provided, the refrigerant whose pressure is higher than that of the refrigerant flowing out of the outdoor heat exchanger (18) can be sucked into the compressor (11). Therefore, the density of the refrigerant sucked into the compressor (11) can be increased as compared with the cycle in which the refrigerant having the same pressure as the refrigerant flowing out from the outdoor heat exchanger (18) is sucked into the compressor (11).

  As a result, it is possible to suppress a decrease in the coefficient of performance (COP) of the refrigeration cycle apparatus (10) including a plurality of heat exchangers that evaporate the refrigerant in different temperature zones. Moreover, it is possible to suppress an abnormal increase in the temperature of the refrigerant discharged from the compressor (11).

  In addition, since the internal heat exchanger (19) is provided, the enthalpy of the refrigerant flowing into the indoor evaporator (15) and the outdoor heat exchanger (18) is reduced, and the indoor evaporator (15) and The amount of heat absorbed in the outdoor heat exchanger (18) can be increased. As a result, it is possible to more effectively suppress the decrease in COP of the refrigeration cycle apparatus (10).

  On the other hand, when the switchgear (21) opens the bypass passage (20), a cycle configuration in which the blown air is not cooled by the indoor evaporator (15) can be realized. Furthermore, since the ejector (16) is provided, it is possible to suppress a decrease in COP of the refrigeration cycle apparatus (10).

  In addition to this, since the internal heat exchanger (19) is provided, the internal heat exchanger (19) was vaporized even when the indoor evaporator (15) switched to a cycle configuration in which the blown air was not cooled. The refrigerant can be caused to flow into the nozzle portion (161). Accordingly, the energy conversion efficiency of the ejector (16) can be improved by increasing the flow rate of the injected refrigerant as compared with the case where the liquid phase refrigerant is caused to flow into the nozzle portion (161). As a result, it is possible to more effectively suppress the decrease in COP of the refrigeration cycle apparatus (10).

Moreover, in invention of Claim 3 , it is a refrigerating-cycle apparatus applied to the air conditioner which adjusts the temperature of the ventilation air ventilated to the air-conditioning object space,
A compressor (11) that compresses and discharges the refrigerant, a radiator (12) that radiates the refrigerant discharged from the compressor (11), and a branching portion that branches the flow of the refrigerant that flows out of the radiator (12) (13), a first decompression device (14) configured to be able to change a throttle opening for depressurizing one refrigerant branched at the branching portion (13), and branched at the branching portion (13) The second decompression device (17) configured to be able to change the throttle opening for decompressing the other refrigerant, and the indoor evaporation for evaporating the refrigerant decompressed by the first decompression device (14) by exchanging heat with the blown air. An outdoor heat exchanger (18) that evaporates the refrigerant decompressed by the second decompression device (17) by heat exchange with the outside air, and a nozzle that depressurizes the refrigerant on the downstream side of the indoor evaporator (15) The suction action of the high-speed jet refrigerant injected from the section (161) A pressure increasing unit (16c) that sucks the refrigerant on the downstream side of the outdoor heat exchanger (18) from the medium suction port (16a) and increases the pressure by mixing the injected refrigerant and the suction refrigerant sucked from the refrigerant suction port (16a). An ejector (16), a first pressure reduction control unit (40b) for controlling the operation of the first pressure reduction device (14), a second pressure reduction control unit (40c) for controlling the operation of the second pressure reduction device (17), With
The refrigerant outlet of the pressurizing unit (16c) is connected to the suction port side of the compressor (11), and the first decompression control unit (40b) is such that the refrigerant flowing out of the indoor evaporator (15) has a superheat degree. The throttle opening degree of the first decompression device (14) is changed so that the gas phase state is obtained, and the second decompression control unit (40c) causes the refrigerant flowing out of the outdoor heat exchanger (18) to be in a gas-liquid two-phase state. Thus, the throttle opening of the second pressure reducing device (17) is changed.

  According to this, the refrigerant can be evaporated in different temperature zones in the indoor evaporator (15) and the outdoor heat exchanger (18), as in the first aspect of the invention. Furthermore, since the ejector (16) is provided, it is possible to suppress a decrease in COP of the refrigeration cycle apparatus (10).

  In addition, the second pressure reduction control unit (40c) changes the throttle opening of the second pressure reduction device (17) so that the refrigerant flowing out of the outdoor heat exchanger (18) is in a gas-liquid two-phase state. Therefore, the pressure loss at the time of a refrigerant | coolant distribute | circulating an outdoor heat exchanger (18) can be reduced rather than the case where the refrigerant | coolant which flows out from an outdoor heat exchanger (18) will be in a gaseous-phase state. Therefore, the power consumption of the compressor (11) can be reduced, and the reduction of the COP of the refrigeration cycle apparatus (10) can be more effectively suppressed.

  Furthermore, since the first pressure reduction control unit (40b) changes the throttle opening of the first pressure reduction device (14) so that the refrigerant flowing out from the indoor evaporator (15) is in a gas phase state having a superheat degree, Even if the refrigerant flowing out from the outdoor heat exchanger (18) is in a gas-liquid two-phase state, the refrigerant flowing out from the pressure increasing unit (16c) of the ejector (16) can be in a gas phase state. Therefore, liquid compression of the compressor (11) can be suppressed.

  In addition, the code | symbol in the bracket | parenthesis of each means described in this column and the claim shows the correspondence with the specific means as described in embodiment mentioned later.

It is a whole block diagram of the vehicle air conditioner of 1st Embodiment. It is an axial sectional view of the ejector of the first embodiment. It is a block diagram which shows the electric control part of the vehicle air conditioner of 1st Embodiment. It is a Mollier diagram which shows the change of the state of the refrigerant | coolant in the ejector type refrigeration cycle of 1st Embodiment. It is an axial sectional view of the ejector of the second embodiment. It is a whole block diagram of the vehicle air conditioner of 3rd Embodiment. It is a Mollier diagram which shows the change of the state of the refrigerant | coolant at the time of the dehumidification heating mode of the ejector-type refrigerating cycle of 3rd Embodiment. It is a Mollier diagram which shows the change of the state of the refrigerant | coolant at the time of the heating mode of the ejector-type refrigerating cycle of 3rd Embodiment. It is a block diagram which shows the electric control part of the vehicle air conditioner of 4th Embodiment. It is a Mollier diagram which shows the change of the state of the refrigerant | coolant at the time of the dehumidification heating mode of the ejector-type refrigerating cycle of 4th Embodiment.

Hereinafter, embodiments of the present invention will be described. Of the embodiments described below, the third and fourth embodiments are the embodiments of the invention described in the claims, and the first and second embodiments are the premise of the present invention. .
(First embodiment)
1st Embodiment of this invention is described using FIGS. 1-4. In the present embodiment, an ejector refrigeration cycle 10 that is a refrigeration cycle apparatus including an ejector 16 is applied to a vehicle air conditioner 1 for an electric vehicle. Here, the electric vehicle is a vehicle that does not include an internal combustion engine (engine) as a driving source for traveling the vehicle, and obtains a driving force for traveling from the traveling electric motor.

  In this type of electric vehicle, engine waste heat cannot be used to heat the passenger compartment, which is the air-conditioning target space. Therefore, the vehicle air conditioner 1 of the present embodiment is used for heating the vehicle interior (specifically, dehumidifying heating). Further, the ejector refrigeration cycle 10 functions to adjust the temperature of the blown air blown into the vehicle interior in the vehicle air conditioner 1.

  The ejector refrigeration cycle 10 employs an HFC refrigerant (specifically, R134a) as the refrigerant, and constitutes a subcritical refrigeration cycle in which the high-pressure side refrigerant pressure does not exceed the refrigerant critical pressure. Of course, an HFO refrigerant (specifically, R1234yf) or the like may be adopted as the refrigerant. Furthermore, refrigeration oil for lubricating the compressor 11 is mixed in the refrigerant, and a part of the refrigeration 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 is disposed in a vehicle bonnet, and sucks, compresses and discharges refrigerant. The compressor 11 is an electric compressor that drives a fixed capacity type compression mechanism with a fixed discharge capacity by an electric motor. Specifically, various compression mechanisms such as a scroll type compression mechanism and a vane type compression mechanism can be employed as the compression mechanism.

  The operation (rotation speed) of the electric motor is controlled by a control signal output from the air conditioning control device 40 described later, and either an AC motor or a DC motor may be adopted. And the refrigerant | coolant discharge capability of a compression mechanism is changed because the air-conditioning control apparatus 40 controls the rotation speed of an electric motor.

  The refrigerant inlet side of the indoor condenser 12 is connected to the discharge port of the compressor 11. The indoor condenser 12 is a radiator that is disposed in a casing 31 of an indoor air conditioning unit 30 to be described later and causes the refrigerant discharged from the compressor 11 and the blown air to exchange heat to dissipate and condense the refrigerant. In other words, the indoor condenser 12 is a heat exchanger for heating that heats the blown air by exchanging heat between the refrigerant discharged from the compressor 11 and blown air after passing through the indoor evaporator 15 described later. .

  One refrigerant inlet / outlet side of the three-way joint 13 is connected to the refrigerant outlet of the indoor condenser 12. The three-way joint 13 is a branch portion that branches the flow of the refrigerant that has flowed out of the indoor condenser 12. That is, the three-way joint 13 of the present embodiment uses one of the three refrigerant inlets as a refrigerant inlet and the remaining two as refrigerant outlets.

  One refrigerant outlet of the three-way joint 13 is connected to the inlet side of the indoor expansion valve 14 that is a first pressure reducing device that depressurizes one refrigerant branched by the three-way joint 13. The indoor expansion valve 14 is a variable throttle mechanism configured to be able to change the throttle opening, a valve body that changes the throttle opening, and an electric actuator that changes the throttle opening by displacing the valve body (specifically Specifically, it has a stepping motor). The operation of the indoor expansion valve 14 is controlled by a control signal (control pulse) output from the air conditioning controller 40.

  The refrigerant inlet side of the indoor evaporator 15 is connected to the outlet of the indoor expansion valve 14. The indoor evaporator 15 is arranged in the casing 31 of the indoor air conditioning unit 30 on the upstream side of the air flow of the indoor condenser 12, and the low-pressure refrigerant decompressed by the indoor expansion valve 14 is supplied to the indoor condenser 12. It is an evaporator that exchanges heat with the blown air before passing and evaporates. In other words, the indoor evaporator 15 is a cooling heat exchanger that cools the blown air by evaporating the low-pressure refrigerant and exerting an endothermic action.

  An inlet side of the nozzle portion 161 of the ejector 16 is connected to the refrigerant outlet of the indoor evaporator 15. The ejector 16 depressurizes and injects the refrigerant on the downstream side of the indoor evaporator 15, sucks the refrigerant from the refrigerant suction port 16a, and sucks the refrigerant from the injection refrigerant and the refrigerant suction port 16a by the suction action of the jet refrigerant injected at a high speed. The pressure is increased by mixing the suctioned refrigerant.

  As shown in FIG. 2, the ejector 16 includes a body portion 160, a nozzle portion 161, a diffuser body 162, and the like.

  The body part 160 is formed of a cylindrical member made of metal (in this embodiment, made of aluminum). The body portion 160 forms an outer shell of the ejector 16 and accommodates the nozzle portion 161 and the like therein. In addition, a refrigerant suction port 16a for sucking a refrigerant (specifically, a refrigerant on the downstream side of the outdoor heat exchanger 18) from the outside to the inside of the body part 160 is formed on the cylindrical side surface of the body part 160. .

  The nozzle portion 161 is formed of a substantially cylindrical member made of metal (in this embodiment, made of a stainless alloy) having a portion that gradually tapers in the refrigerant flow direction. The nozzle part 161 is an isentropic decompression of the refrigerant in the refrigerant passage (throttle passage) formed therein, and ejects it from the refrigerant injection port 161a.

  More specifically, the refrigerant passage in the nozzle portion 161 is formed with a throat portion (minimum passage cross-sectional area portion) 161b where the refrigerant passage cross-sectional area is reduced most. Therefore, the refrigerant passage is provided with a tapered portion in which the passage sectional area gradually decreases toward the throat portion 161b and a divergent portion in which the passage sectional area gradually increases from the throat portion 161b toward the refrigerant injection port 161a. ing. That is, the nozzle part 161 of the present embodiment is configured as a Laval nozzle.

  Further, in the present embodiment, the nozzle unit 161 is set such that the flow rate of the injected refrigerant injected from the refrigerant injection port of the nozzle unit 161 is equal to or higher than the sonic speed during normal operation of the ejector refrigeration cycle 10. Has been. Further, the outer peripheral portion of the nozzle portion 161 is fixed to the inner peripheral portion on one end side in the longitudinal direction of the body portion 160 by means such as press fitting. Therefore, the refrigerant does not leak from the fixing part (press-fit part) between the body part 160 and the nozzle part 161.

  The diffuser body 162 is formed of a cylindrical member made of metal (in this embodiment, made of aluminum). The diffuser body 162 forms a suction passage 16 b and a diffuser portion 16 c inside the body portion 160.

  More specifically, the diffuser body 162 is fixed to the inside of the body portion 160 by a means such as press-fitting so as not to contact the nozzle portion 161 at a portion downstream of the refrigerant flow of the nozzle portion 161. . In other words, the diffuser body 162 is fixed to the nozzle part 161 at an interval in the central axis direction. For this reason, a space is formed between a portion of the nozzle portion 161 on the downstream side of the refrigerant flow and a portion of the diffuser body 162 on the upstream side of the refrigerant flow.

  This space communicates with the refrigerant suction port 16a and forms a suction passage 16b that guides the refrigerant sucked from the refrigerant suction port 16a to the refrigerant injection port 161a side of the nozzle portion 161. Further, the suction passage 16b is formed in an annular cross section around the refrigerant injection port 161a side of the nozzle portion 161, and has a shape in which the passage cross-sectional area gradually decreases toward the downstream side of the refrigerant flow. .

  The diffuser portion 16 c is formed by a space on the inner peripheral side of the diffuser body 162. The diffuser portion 16c is formed in a substantially truncated cone shape whose passage cross-sectional area gradually increases toward the refrigerant flow downstream side. The central axis of the diffuser part 16 c is arranged coaxially with the central axis of the refrigerant passage in the nozzle part 161.

  In the diffuser part 16c, since the passage cross-sectional area gradually increases, the flow rate of the mixed refrigerant can be reduced and increased while mixing the injected refrigerant and the suction refrigerant sucked from the refrigerant suction port 16a. Therefore, the diffuser part 16c is a pressure increasing part that pressurizes the mixed refrigerant by converting the velocity energy of the mixed refrigerant into pressure energy.

  Further, inside the ejector 16, there are a valve body part 163 that changes the passage sectional area of the refrigerant passage in the nozzle part 161 and the passage sectional area of the refrigerant passage in the diffuser body 162 (that is, the diffuser part 16 c), and a valve The drive part 164 which displaces the body part 163 is accommodated.

  The valve body 163 is formed of a resin conical member whose outer diameter increases toward the downstream side of the refrigerant flow. The central axis of the valve body part 163 is arranged coaxially with the central axis of the refrigerant passage in the nozzle part 161 and the central axis of the diffuser part 16c. And the top part of the valve body part 163 is arrange | positioned in the refrigerant path in the nozzle part 161, and the skirt part (site | part downstream from a top part) of the valve body part 163 is arrange | positioned in the diffuser part 16c.

  For this reason, the refrigerant passage of the nozzle part 161 is formed between the inner peripheral wall surface of the nozzle part 161 and the outer peripheral wall surface of the top part of the valve body part 163. The diffuser portion 16 c is formed in an annular cross section between the inner peripheral wall surface of the diffuser body 162 and the outer peripheral wall surface of the skirt portion of the valve body portion 163.

  And the drive part 164 can change the channel | path cross-sectional area of the nozzle part 161 and the channel | path cross-sectional area of the diffuser part 16c by displacing the valve body part 163 to a center axis direction. That is, the valve body part 163 of this embodiment has the function to change the passage cross-sectional area of the refrigerant path in the nozzle part 161, and the function to change the passage cross-sectional area of the diffuser part 16c.

  The drive unit 164 includes an annular groove 162a, a diaphragm 164a, a lid member 164b, and the like formed on the surface of the diffuser body 162 on the suction passage 16b side. The diaphragm 164a is a thin plate-like pressure responsive member. The lid member 164b is a disk-shaped member made of metal (made of aluminum in this embodiment) for closing the opening of the groove 162a.

  The diaphragm 164a and the lid member 164b are both formed in an annular shape that is substantially equivalent to the groove 162a when viewed from the axial direction. Further, an annular recess is formed on the surface of the lid member 164b opposite to the suction passage 16b.

  As shown in FIG. 2, the lid member 164b is fixed by means such as press fitting or caulking so as to close the groove 162a in a state where the diaphragm 164a is disposed inside the groove 162a.

  Thereby, the inner peripheral side edge part and outer peripheral side edge part of the diaphragm 164a are clamped between the diffuser body 162 and the lid member 164b. The space formed between the lid member 164b and the groove 162a is divided into two upper and lower spaces by the diaphragm 164a.

  Of the two spaces partitioned by the diaphragm 164a, the space on the suction passage 16b side (that is, the space formed in the recess of the lid member 164b) is the temperature change of the refrigerant on the downstream side of the outdoor heat exchanger 18 that is the suction refrigerant. This is an enclosed space 16d in which a temperature-sensitive medium whose pressure changes with the inside is enclosed. Therefore, the lid member 164b is a sealed space forming member that forms the sealed space 16d together with the diaphragm 164a.

  A temperature-sensitive medium having the same composition as the refrigerant circulating in the ejector refrigeration cycle 10 is enclosed in the enclosed space 16d. Therefore, the temperature sensitive medium of the present embodiment is a fluid mainly composed of R134a, and for example, a mixed fluid of R134a and helium can be employed. Furthermore, the sealing density of the temperature sensitive medium is set so that the valve body 163 can be appropriately displaced during the operation of the cycle, as will be described later.

  On the other hand, of the two spaces partitioned by the diaphragm 164a, the space far from the suction passage 16b (that is, the space formed in the groove 162a) passes through a communication passage (not shown) formed in the diffuser body 162. This is an introduction space 16e for introducing the suction refrigerant. Therefore, the temperature of the suction refrigerant flowing through the suction passage 16b is transmitted to the temperature sensitive medium sealed in the sealed space 16d through the lid member 164b and the diaphragm 164a.

  The diaphragm 164a is a pressure responsive member that is displaced according to a pressure difference between the internal pressure of the enclosed space 16d and the pressure of the refrigerant on the outlet side of the indoor evaporator 15 that has flowed into the introduction space 16e. Therefore, it is desirable that the diaphragm 164a be formed of a material that is rich in elasticity and excellent in pressure resistance and airtightness.

  Examples of such a diaphragm 164a include a metal thin plate such as stainless steel (SUS304), and a rubber base material such as EPDM (ethylene propylene diene rubber) or HNBR (hydrogenated nitrile rubber) containing a base fabric (polyester). What was formed can be adopted.

  The diaphragm 164a is provided with a plurality of operating rods 164c (three in this embodiment) for transmitting the displacement of the diaphragm 164a to the valve body 163. The plurality of operating rods 164c are arranged at equiangular intervals (180 ° intervals in this embodiment) around the central axis of the valve body 163 in order to appropriately transmit the displacement of the diaphragm 164a to the valve body 163. It is desirable that

  Further, the bottom surface of the valve body portion 163 receives a load of the coil spring 166 a supported by the support member 166. The support member 166 is a metal disk-like member formed with a plurality of refrigerant outlets 166b through which the refrigerant that has flowed out of the diffuser portion 16c flows out. The outer peripheral portion of the support member 166 is fixed to the inner peripheral portion of the body portion 160 on the most downstream side of the refrigerant flow (that is, the other end side in the longitudinal direction of the body portion 160) by means such as press fitting.

  The coil spring 166a is an elastic member that applies a load to the valve body 163 to bias the passage cross-sectional area in the throat portion 161b of the nozzle portion 161 and the passage cross-sectional area in the diffuser portion 16c toward the side to reduce. Accordingly, the valve body 163 is displaced so that the load received from the operating rod 164c and the load received from the coil spring 166a are balanced.

  For this reason, under the condition where the pressure of the suction refrigerant is constant, when the temperature (superheat degree) of the suction refrigerant rises, the saturation pressure of the temperature-sensitive medium enclosed in the enclosed space 16d rises and is introduced from the internal pressure of the enclosed space 16d. The pressure difference obtained by subtracting the pressure in the space 16e increases. As a result, the diaphragm 164a is displaced toward the introduction space 16e, and the load that the valve body 163 receives from the operating rod 164c increases.

  Therefore, under the condition where the pressure of the suction refrigerant is constant, when the temperature (superheat degree) of the suction refrigerant rises, the valve body portion 163 enlarges the passage cross-sectional area in the throat portion 161b and the passage cross-sectional area in the diffuser portion 16c. It is displaced to. On the contrary, when the temperature (superheat degree) of the suction refrigerant decreases, the valve body portion 163 is displaced in a direction to reduce the passage cross-sectional area in the throat portion 161b and the passage cross-sectional area in the diffuser portion 16c.

  Thus, by displacing the valve body portion 163 according to the temperature (superheat degree) of the suction refrigerant, the superheat degree of the refrigerant on the outlet side of the outdoor heat exchanger 18 can be brought close to a predetermined reference superheat degree. If the reference superheat degree is set to 0, the refrigerant on the outlet side of the outdoor heat exchanger 18 can be in a gas-liquid two-phase state.

  On the other hand, under the condition where the superheat degree of the suction refrigerant is constant, when the pressure of the suction refrigerant decreases, the pressure difference obtained by subtracting the pressure of the suction refrigerant from the pressure of the refrigerant boosted by the diffuser portion 16c increases. Due to this pressure difference, the valve body portion 163 is displaced in a direction in which the passage cross-sectional area in the throat portion 161b and the passage cross-sectional area in the diffuser portion 16c are reduced. On the other hand, when the pressure of the suction refrigerant increases, the passage sectional area in the throat portion 161b and the passage sectional area in the diffuser portion 16c are displaced in the direction of enlargement.

  Further, an O-ring (not shown) is disposed in the gap between the operating rod 164c and the diffuser body 162 of the present embodiment, and the refrigerant does not leak from the gap even when the operating rod 164c is displaced. As shown in FIG. 1, the inlet side of the compressor 11 is connected to the refrigerant outlet of the diffuser part 16c.

  The other refrigerant outlet of the three-way joint 13 is connected to the inlet side of the outdoor expansion valve 17 that is a second pressure reducing device that depressurizes the other refrigerant branched by the three-way joint 13. The basic configuration of the outdoor expansion valve 17 is the same as that of the indoor expansion valve 14. Therefore, the outdoor expansion valve 17 is a variable throttle mechanism configured to be able to change the throttle opening. Furthermore, the operation of the outdoor expansion valve 17 is controlled by a control signal (control pulse) output from the air conditioning controller 40.

  The refrigerant inlet side of the outdoor heat exchanger 18 is connected to the outlet of the outdoor expansion valve 17. The outdoor heat exchanger 18 is disposed on the vehicle front side in the vehicle bonnet, and exchanges heat with outdoor air (outside air) blown from a blower fan (not shown) for the low-pressure refrigerant decompressed by the outdoor expansion valve 17. This is an evaporator that evaporates. In other words, the outdoor heat exchanger 18 is an endothermic heat exchanger that evaporates low-pressure refrigerant and exerts an endothermic effect.

  The refrigerant suction port 16 a side of the ejector 16 is connected to the refrigerant outlet of the outdoor heat exchanger 18.

  Next, the indoor air conditioning unit 30 will be described. The indoor air conditioning unit 30 performs a function of distributing the blown air whose temperature is adjusted by the ejector-type refrigeration cycle 10 into the vehicle interior, and is disposed inside the instrument panel (instrument panel) at the forefront of the vehicle interior. . As shown in FIG. 1, the indoor air conditioning unit 30 is configured by housing a blower 32, an indoor evaporator 15, an indoor condenser 12, and the like in a casing 31 that forms an outer shell thereof.

  The casing 31 forms an air passage for blown air blown into the vehicle interior, and is formed of a resin (for example, polypropylene) having a certain degree of elasticity and excellent in strength. On the most upstream side of the blast air flow in the casing 31, an inside / outside air switching device 33 is arranged as an inside / outside air switching means for switching and introducing the inside air (vehicle compartment air) and the outside air (vehicle compartment outside air) into the casing 31. ing.

  The inside / outside air switching device 33 continuously adjusts the opening area of the inside air introduction port through which the inside air is introduced into the casing 31 and the outside air introduction port through which the outside air is introduced by the inside / outside air switching door, so that the air volume of the inside air and the air volume of the outside air are adjusted. The air volume ratio is continuously changed. The inside / outside air switching door is driven by an electric actuator for the inside / outside air switching door, and the operation of the electric actuator is controlled by a control signal output from the air conditioning control device 40.

  A blower 32 that blows the air sucked through the inside / outside air switching device 33 toward the vehicle interior is disposed on the downstream side of the blowing air flow of the inside / outside air switching device 33. The blower 32 is an electric blower that drives a centrifugal multiblade fan (sirocco fan) with an electric motor, and the rotation speed (that is, the blowing capacity) is controlled by a control voltage output from the air conditioning control device 40.

  On the downstream side of the blower air flow of the blower 32, the indoor evaporator 15 and the indoor condenser 12 are arranged in this order with respect to the flow of the blown air. In other words, the indoor evaporator 15 is arranged on the upstream side of the blown air flow with respect to the indoor condenser 12. Further, in the casing 31, a cold air bypass passage 35 is formed in which the blown air that has passed through the indoor evaporator 15 is caused to bypass the indoor condenser 12 and flow downstream.

  An air mix door 34 is arranged on the downstream side of the blower air flow of the indoor evaporator 15 and on the upstream side of the blower air flow of the indoor condenser 12. The air mix door 34 is an air volume ratio adjusting unit that adjusts the air volume ratio between the air volume guided to the indoor condenser 12 side and the air volume guided to the cold air bypass passage 35 side among the cold air after passing through the indoor evaporator 15.

  The air mix door 34 is driven by an electric actuator for driving the air mix door, and the operation of the electric actuator is controlled by a control signal output from the air conditioning control device 40.

  On the downstream side of the blower air flow of the indoor condenser 12, a mixing space is provided for mixing the blown air (hot air) heated by the indoor condenser 12 and the blown air (cold air) that has passed through the cold air bypass passage 35. Yes. Therefore, the air mix door 34 adjusts the air volume ratio, thereby adjusting the temperature of the blown air (air conditioned air) mixed in the mixing space.

  Furthermore, a face opening hole, a foot opening hole, and a defroster opening hole (all not shown) for blowing the blowing air (air conditioned air) flowing into the mixing space into the vehicle interior are provided at the most downstream portion of the blowing air flow of the casing 31. Is provided.

  The face opening hole is an opening hole for blowing conditioned air toward the upper body of the passenger in the vehicle interior. The foot opening hole is an opening hole for blowing out the conditioned air toward the passenger's feet. The defroster opening hole is an opening hole that blows conditioned air toward the inner side surface of the vehicle front window glass. These face opening holes, foot opening holes, and defroster opening holes are respectively provided on the downstream side of the blown air flow through ducts that form air passages, face outlets, foot outlets, and defroster outlets provided in the passenger compartment. (Both not shown).

  Further, on the upstream side of the air flow of the face opening hole, foot opening hole, and defroster opening hole, a face door for adjusting the opening area of the face opening hole, a foot door for adjusting the opening area of the foot opening hole, and a defroster opening, respectively. A defroster door (both not shown) for adjusting the opening area of the hole is disposed.

  These face doors, foot doors, and defroster doors constitute opening hole mode switching means for switching the opening hole mode, and are linked to an electric actuator for driving the outlet mode door via a link mechanism or the like. And rotated. The operation of the electric actuator is controlled by a control signal output from the air conditioning controller 40.

  Examples of the air outlet mode switched by the air outlet mode switching means include a face mode, a bi-level mode, and a foot mode. The face mode is an air outlet mode in which the face air outlet is fully opened and air is blown out from the face air outlet toward the upper body of the passenger in the passenger compartment. The bi-level mode is an air outlet mode that opens both the face air outlet and the foot air outlet and blows air toward the upper body and the feet of the passengers in the passenger compartment. The foot mode is an air outlet mode that mainly blows air from the foot air outlet toward the feet of the occupant.

  Further, the defroster mode in which the occupant manually operates the blow mode switching switch provided on the operation panel 60 to fully open the defroster blowout port and blow out air from the defroster blowout port to the inner surface of the vehicle front window glass can be set.

  Next, the electric control unit of the present embodiment will be described with reference to FIG. The air conditioning control device 40 includes a known microcomputer including a CPU, a ROM, a RAM, and the like and peripheral circuits thereof. Then, various calculations and processes are performed based on the air conditioning control program stored in the ROM, and the compressor 11, the indoor expansion valve 14, the outdoor expansion valve 17, the blower 32, etc. connected to the output side thereof. Control the operation of various devices.

  A sensor group for air conditioning control is connected to the input side of the air conditioning control device 40, and a detection signal detected by the sensor group for air conditioning control is input. Specifically, the air conditioning control sensor group includes an inside air sensor 51, an outside air sensor 52, a solar radiation sensor 53, an indoor evaporator temperature sensor 54, an outdoor heat exchanger temperature sensor 55, a blown air temperature sensor 56, and the like. Yes.

  The inside air sensor 51 is an inside air temperature detecting device that detects a vehicle interior temperature (inside air temperature) Tr. The outside air sensor 52 is an outside air temperature detecting device that detects an outside temperature (outside air temperature) Tam of the passenger compartment. The solar radiation sensor 53 is a solar radiation amount detection device that detects the solar radiation amount As irradiated into the vehicle interior. The indoor evaporator temperature sensor 54 is an indoor evaporator temperature detection device that detects an indoor unit refrigerant evaporation temperature (indoor evaporator temperature) Te1 in the indoor evaporator 15. The outdoor heat exchanger temperature sensor 55 is an outdoor heat exchanger temperature detection device that detects an outdoor refrigerant evaporating temperature (outdoor heat exchanger temperature) Te2 in the outdoor heat exchanger 18. The blown air temperature sensor 56 is a blown air temperature detection device that detects the blown air temperature TAV blown from the mixing space into the vehicle interior.

  Furthermore, an operation panel 60 disposed near the instrument panel in the front of the passenger compartment is connected to the input side of the air conditioning control device 40, and operation signals of various air conditioning operation switches provided on the operation panel 60 are input. The

  As the various air conditioning operation switches of the operation panel 60, an auto switch, an air volume setting switch, a temperature setting switch, a blow mode switching switch, and the like are provided. The auto switch is a switch for setting or canceling the automatic control operation of the vehicle air conditioner 1. The air volume setting switch is a switch for manually setting the air volume of the blower 32. The temperature setting switch is a switch for setting a vehicle interior set temperature Tset that is a target temperature in the vehicle interior. The blowing mode changeover switch is a switch for manually setting the blowing mode.

  The air-conditioning control device 40 is configured integrally with a control unit that controls various air-conditioning control devices connected to the output side of the air-conditioning control device 40. The configuration (hardware and hardware) controls the operation of each air-conditioning control device. Software) constitutes a control unit that controls the operation of each air conditioning control device.

  For example, in this embodiment, the structure which controls the action | operation (refrigerant discharge capability) of the compressor 11 comprises the discharge capability control part 40a. Moreover, the structure which controls the action | operation of an indoor expansion valve comprises the 1st pressure reduction control part 40b. Moreover, the structure which controls the action | operation of the outdoor expansion valve comprises the 2nd pressure reduction control part 40c. Of course, the discharge capacity control unit 40a and the like may be configured as a separate control device with respect to the air conditioning control device 40.

  Next, the operation of the vehicle air conditioner 1 of the present embodiment having the above configuration will be described. In the vehicle air conditioner 1 of this embodiment, the vehicle interior is dehumidified and heated by executing an air conditioning control program stored in the air conditioning controller 40 in advance. This air conditioning control program is executed when the auto switch of the operation panel 60 is turned on.

  In the main routine of the air conditioning control program, the detection signals of the sensor groups 51 to 56 for air conditioning control, the operation signals of the operation panel 60, and the like are read. And based on the read detection signal and operation signal, the target blowing temperature TAO which is the target temperature of the blowing air which blows off into the vehicle interior is calculated.

The target blowing temperature TAO is calculated by the following formula F1.
TAO = Kset × Tset−Kr × Tr−Kam × Tam−Ks × As + C (F1)
Here, Tset is the vehicle interior set temperature set by the temperature setting switch, Tr is the vehicle interior temperature (inside air temperature) detected by the inside air sensor 51, Tam is the outside air temperature detected by the outside air sensor 52, and As is a solar radiation sensor. The amount of solar radiation detected by 53. Kset, Kr, Kam, Ks are control gains, and C is a correction constant.

  Further, the air conditioning control device 40 determines the operating states of the various control target devices (control signals to be output to the various control target devices) based on the target blowing temperature TAO, the detection signal of the sensor group, and the like.

  For example, for the refrigerant discharge capacity of the compressor 11 (control signal output to the electric motor of the compressor 11), a control map stored in the air conditioning control device 40 in advance based on the outside air temperature Tam and the target blowing temperature TAO. Determined by reference. Specifically, in this control map, the refrigerant discharge capacity of the compressor 11 is determined to increase as the outside air temperature Tam decreases and the target outlet temperature TAO increases.

  As for the throttle opening degree of the outdoor expansion valve 17 (control signal output to the outdoor expansion valve 17), the outdoor heat exchanger temperature Te2 detected by the outdoor heat exchanger temperature sensor 55 is subtracted from the outdoor temperature Tam. The determined deviation (Tam−Te2) is determined to be a predetermined reference deviation (10 ° C. in the present embodiment).

  As for the throttle opening degree of the indoor expansion valve 14 (control signal output to the indoor expansion valve 14), the indoor evaporator temperature Te1 detected by the indoor evaporator temperature sensor 54 is a predetermined reference evaporation temperature. It is determined so as to approach KTe1 (15 ° C. in this embodiment).

  Moreover, about the ventilation capability (control voltage output to the air blower 32) of the air blower 32, it determines with reference to the control map previously memorize | stored in the air-conditioning control apparatus 40 based on the target blowing temperature TAO. Specifically, in this control map, it determines so that the ventilation volume of the air blower 32 may be increased with the raise of the target blowing temperature TAO.

  Moreover, about the control signal output to the electric actuator of the air mix door 34, it determines so that the blowing air temperature TAV detected by the blowing air temperature sensor 56 may approach the target blowing temperature TAO using a feedback control method. .

  And the air-conditioning control apparatus 40 outputs the control signal etc. which were determined as mentioned above to various control object apparatus. Thereafter, until the operation stop of the vehicle air conditioner 1 is requested, the above-described detection signal and operation signal are read at every predetermined control cycle → the target blowing temperature TAO is calculated → the operating states of various control target devices are determined → A control routine such as output of a control voltage and a control signal is repeated.

  Therefore, in the ejector refrigeration cycle 10, the refrigerant flows as shown by the black arrow in FIG. 1, and the state of the refrigerant changes as shown in the Mollier diagram of FIG. That is, the refrigerant discharged from the compressor 11 (point a4 in FIG. 4) flows into the indoor condenser 12, exchanges heat with the blown air cooled and dehumidified by the indoor evaporator 15, and dissipates heat ( A4 point in FIG. 4 → b4 point). Thereby, the blown air after passing through the indoor evaporator 15 is heated.

  The refrigerant flow that has flowed out of the indoor condenser 12 is branched at the three-way joint 13. One refrigerant branched by the three-way joint 13 is decompressed by the indoor expansion valve 14 (b4 point → c4 point in FIG. 4). The low-pressure refrigerant decompressed by the indoor expansion valve 14 flows into the indoor evaporator 15 and evaporates by absorbing heat from the blown air blown from the blower 32 (point c4 → point d4 in FIG. 4).

  Thereby, blowing air is cooled and dehumidified. At this time, in the indoor evaporator 15 of the present embodiment, the blown air is cooled to the reference evaporation temperature KTe1 (specifically, 15 ° C.). Here, according to the study by the present inventors, the inside air sucked from the passenger compartment through the inside / outside air switching device 33 is cooled to about 15 ° C., which is sufficient for anti-fogging of the vehicle window glass. It is known that it can be dehumidified.

  The refrigerant that has flowed out of the indoor evaporator 15 flows into the nozzle portion 161 of the ejector 16 and is isentropically decompressed and injected (point d4 → point e4 in FIG. 4). Then, the refrigerant on the downstream side of the outdoor heat exchanger 18 (i4 point in FIG. 4) is sucked from the refrigerant suction port 16a of the ejector 16 by the suction action of the jet refrigerant.

  The suction refrigerant sucked from the refrigerant suction port 16a is decompressed in an isentropic manner because the passage cross-sectional area of the suction passage 16b is gradually reduced toward the downstream side of the refrigerant flow, and the flow velocity is increased. (I4 point → j4 point in FIG. 4). In this embodiment, by increasing the flow rate of the suction refrigerant and reducing the speed difference from the injection refrigerant in this way, energy loss (mixing) when the suction refrigerant and the injection refrigerant are merged in the diffuser portion 16c. Loss).

  In the diffuser part 16c, the injection refrigerant and the suction refrigerant are mixed. Furthermore, the velocity energy of the mixed refrigerant is converted into pressure energy due to the enlargement of the cross-sectional area of the passage, and the pressure of the mixed refrigerant increases (point f4 → point g4 in FIG. 4). The refrigerant flowing out from the diffuser portion 16c is sucked into the compressor 11 and compressed again (point g4 → point a4 in FIG. 4).

  On the other hand, the other refrigerant branched by the three-way joint 13 flows into the outdoor expansion valve 17 and is decompressed in an isoenthalpy manner (b4 point → h4 point in FIG. 4). At this time, the throttle opening degree of the outdoor expansion valve 17 is adjusted so that the refrigerant evaporation temperature in the outdoor heat exchanger 18 is lower than the outside air temperature Tam, and the pressure of the refrigerant decompressed by the outdoor expansion valve 17 is adjusted. Is lower than the pressure of the refrigerant decompressed by the indoor expansion valve 14.

  The refrigerant decompressed by the outdoor expansion valve 17 flows into the outdoor heat exchanger 18 and absorbs heat from the outside air blown from the blower fan to evaporate (point f4 → point g4 in FIG. 4). The refrigerant that has flowed out of the outdoor heat exchanger 18 is sucked from the refrigerant suction port 16 a of the ejector 16.

  The vehicle air conditioner 1 of this embodiment operates as described above, and cools and dehumidifies the air blown into the passenger compartment by the indoor evaporator 15. Further, the blown air dehumidified by the indoor condenser 12 is reheated. And the dehumidification heating in a vehicle interior is realizable by blowing off the reheated ventilation air to a vehicle interior.

  Further, in the ejector refrigeration cycle 10 of the present embodiment, the refrigerant decompressed by the indoor expansion valve 14 is evaporated by the indoor evaporator 15 and the refrigerant decompressed by the outdoor expansion valve 17 is exchanged by the outdoor heat. Since the evaporator 18 evaporates, the refrigerant can be evaporated in different temperature zones with a plurality of heat exchangers functioning as an evaporator.

  At this time, since the refrigerant evaporation temperature in the indoor evaporator 15 is set to 0 ° C. or higher (specifically, about 15 ° C.), the blown air is cooled and dehumidified while suppressing frost formation in the indoor evaporator 15. Can do. Further, since the refrigerant evaporation temperature in the outdoor heat exchanger 18 is set to a temperature lower than the outside air temperature (specifically, a temperature lower by 10 ° C. than the outside air temperature), the heat for heating the blown air from the outside air is reliably ensured. Can absorb heat.

  Furthermore, in the ejector refrigeration cycle 10 of the present embodiment, the refrigerant whose pressure has been increased by the diffuser portion 16 c of the ejector 16 is sucked into the compressor 11. Therefore, the density of the refrigerant sucked in the compressor 11 can be increased as compared with the refrigeration cycle apparatus in which the compressor 11 sucks the refrigerant having the same pressure as the refrigerant flowing out of the outdoor heat exchanger 18.

  As a result, according to the ejector refrigeration cycle 10 of the present embodiment, it is possible to suppress a decrease in the coefficient of performance (COP) of the refrigeration cycle apparatus including a plurality of heat exchangers that evaporate the refrigerant in different temperature zones. Furthermore, an abnormal rise in the temperature of the refrigerant discharged from the compressor 11 can also be suppressed.

  Moreover, in the ejector 16 of this embodiment, the drive part 164 displaces the valve body part 163 so that the passage cross-sectional area of the nozzle part 161 may be reduced as the suction refrigerant pressure decreases. According to this, like the constant pressure regulating valve of the prior art, even if the refrigerant evaporation temperature in the outdoor heat exchanger 18 decreases, the refrigerant evaporation temperature in the indoor evaporator 15 can be maintained at the reference evaporation temperature KTe1 or higher. it can.

  This is extremely effective in the refrigeration cycle apparatus applied to the air conditioner in that it is easy to maintain the refrigerant evaporation temperature in the indoor evaporator 15 at or above the temperature at which frost formation does not occur.

  Here, in order to prevent the indoor evaporator 15 from frosting, the reference evaporation temperature KTe1 may be set to a temperature higher than 0 ° C. In contrast, in the present embodiment, the reference evaporation temperature KTe1 is set to 15 ° C., so that the pressure of the refrigerant flowing into the nozzle portion 161 of the ejector 16 can be increased. As a result, the boosting capability of the ejector 16 can be improved, and the reduction in COP of the refrigeration cycle apparatus can be more effectively suppressed.

  Moreover, in the ejector 16 of this embodiment, when the drive part 164 displaces the valve body part 163, both the passage sectional area of the nozzle part 161 and the passage sectional area of the diffuser part 16c can be changed. Accordingly, the ejector 16 can be appropriately operated by changing both the passage cross-sectional area of the nozzle portion 161 and the passage cross-sectional area of the diffuser portion 16c in accordance with changes in the outside air temperature Tam and the like.

(Second Embodiment)
This embodiment demonstrates the example which changed the structure of the ejector 26 with respect to 1st Embodiment, as shown in FIG. In FIG. 5, 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.

  More specifically, the ejector 26 of the present embodiment includes a needle valve 163a disposed in the refrigerant passage in the nozzle portion 161 as a valve body portion. The needle valve 163a is formed in a substantially conical shape that tapers from the upstream side to the downstream side of the refrigerant flow. Therefore, the needle valve 163a of the present embodiment has a function of changing the passage sectional area of the nozzle portion 161 and does not have a function of changing the passage sectional area of the diffuser portion 16c.

  In addition, the drive unit 164 of the present embodiment includes an annular groove 161c, a diaphragm 164a, a lid member 164b, and the like formed on the surface of the nozzle unit 161 on the suction passage 16b side.

  Similarly to the first embodiment, the drive unit 164 of the present embodiment also has a passage break in the throat portion 161b as the suction refrigerant temperature (superheat degree) increases under the condition that the suction refrigerant pressure is constant. The needle valve 163a is displaced in the direction of increasing the area. Conversely, the needle valve 163a is displaced in a direction that reduces the cross-sectional area of the passage in the throat 161b as the temperature (superheat degree) of the suction refrigerant decreases.

  Further, under a condition where the superheat degree of the suction refrigerant is constant, the needle valve 163a is displaced in a direction to reduce the passage cross-sectional area in the throat portion 161b as the suction refrigerant pressure decreases. Conversely, as the suction refrigerant pressure increases, the needle valve 163a is displaced in a direction in which the passage sectional area of the throat 161b is enlarged.

  Further, in the present embodiment, the support member 166 that supports the coil spring 166a is eliminated, and the coil spring 166a is accommodated in the space upstream of the refrigerant flow of the nozzle portion 161 in the body portion 160. In the same manner as in the first embodiment, a load that biases the needle valve 163a toward the side that reduces the cross-sectional area of the passage in the throat portion 161b is applied.

  Other configurations and operations of the ejector 26 and the vehicle air conditioner 1 are the same as those in the first embodiment. Therefore, also in the vehicle air conditioner 1 of the present embodiment, dehumidifying heating in the passenger compartment can be realized as in the first embodiment. Furthermore, also in the ejector refrigeration cycle 10 of the present embodiment, it is possible to suppress a decrease in COP of a refrigeration cycle apparatus including a plurality of heat exchangers as in the first embodiment.

(Third embodiment)
In the present embodiment, an example in which the configuration of the ejector refrigeration cycle 10 is changed as shown in the overall configuration diagram of FIG. 6 with respect to the first embodiment will be described. More specifically, the ejector refrigeration cycle 10 of the present embodiment has an internal heat exchanger 19, a bypass passage 20, and a three-way valve 21 added to the first embodiment. Furthermore, the refrigerant circuit in the dehumidifying and heating mode and the refrigerant circuit in the heating mode can be switched.

  The internal heat exchanger 19 includes a high-pressure side refrigerant flowing through a refrigerant flow path from the refrigerant outlet of the indoor condenser 12 to the refrigerant inlet side of the three-way joint 13, and a low-pressure side refrigerant decompressed by the indoor expansion valve 14. Is a heat exchanger for exchanging heat.

  As such an internal heat exchanger 19, the low-pressure side refrigerant flowing out from the indoor evaporator 15 is circulated inside the outer pipe that forms the high-pressure side refrigerant passage through which the high-pressure side refrigerant flowing out from the indoor condenser 12 circulates. A double-pipe heat exchanger having an inner pipe that forms the low-pressure side refrigerant passage may be employed.

  The bypass passage 20 is a refrigerant pipe that guides the low-pressure side refrigerant depressurized by the indoor expansion valve 14 to the inlet side of the low-pressure side refrigerant passage of the internal heat exchanger 19 by bypassing the indoor evaporator 15.

  The three-way valve 21 is disposed at the most upstream portion of the bypass passage 20, and a refrigerant circuit that causes the low-pressure refrigerant decompressed by the indoor expansion valve 14 to flow out to the refrigerant inlet side of the indoor evaporator 15, and the indoor expansion valve 14 is switched to a refrigerant circuit that causes the low-pressure refrigerant depressurized at 14 to flow out to the bypass passage 20 side.

  That is, the three-way valve 21 of the present embodiment is an opening / closing device that opens and closes the bypass passage 20. The operation of the three-way valve 21 is controlled by a control signal output from the air conditioning control device 40. Other configurations of the ejector refrigeration cycle 10 and the vehicle air conditioner 1 are the same as those in the first embodiment.

  Next, the operation of the vehicle air conditioner 1 of the present embodiment will be described. In the vehicle air conditioner 1 of the present embodiment, it is possible to switch between the dehumidifying heating mode and the heating mode in which the blowing air is not dehumidified. Switching between the dehumidifying and heating mode and the heating mode is performed by an occupant operating a changeover switch provided on the operation panel 60.

  When the dehumidifying and heating mode is selected by the changeover switch, the air conditioning control device 40 operates the three-way valve 21 so that the low-pressure refrigerant decompressed by the indoor expansion valve 14 flows into the indoor evaporator 15. Control. As a result, in the ejector refrigeration cycle 10, the refrigerant flows as shown by the black arrow in FIG. 6, and the state of the refrigerant changes as shown in the Mollier diagram of FIG.

  7 are the same as those in the Mollier diagram of FIG. 4 described in the first embodiment for the same or corresponding refrigerant state in the cycle configuration. The alphabet is used and the subscripts (numbers) are changed. The same applies to the following Mollier diagram.

  More specifically, in the dehumidifying heating mode, the internal heat exchanger 19 exchanges heat between the high-pressure side refrigerant flowing out of the indoor condenser 12 and the low-pressure side refrigerant flowing out of the indoor evaporator 15. As a result, the high-pressure refrigerant flowing out of the indoor condenser 12 decreases enthalpy (b7 point → bα7 point in FIG. 7), and the low-pressure refrigerant flowing out of the indoor evaporator 15 increases enthalpy (point d7 in FIG. 7). → dα7 points).

  Other operations are the same as those in the first embodiment. Accordingly, in the dehumidifying and heating mode in which the three-way valve 21 closes the bypass passage 20, dehumidifying heating in the vehicle compartment can be realized as in the first embodiment.

  Further, in the ejector refrigeration cycle 10 in the dehumidifying and heating mode, the refrigerant can be evaporated in different temperature zones in the indoor evaporator 15 and the outdoor heat exchanger 18 as in the first embodiment. Furthermore, since the ejector 16 is provided, the density of the refrigerant sucked by the compressor 11 can be increased, and the decrease in the COP of the ejector refrigeration cycle 10 can be suppressed.

  In addition, since the internal heat exchanger 19 is provided, it is possible to reduce the enthalpy of the refrigerant flowing into the indoor evaporator 15 and the outdoor heat exchanger 18 and increase the heat absorption amount in the outdoor heat exchanger 18. it can. As a result, the COP of the ejector refrigeration cycle 10 can be suppressed more effectively.

  When the heating mode is selected by the changeover switch, the air conditioning control device 40 causes the low-pressure refrigerant decompressed by the indoor expansion valve 14 to bypass the indoor evaporator 15 and flow into the internal heat exchanger 19. In this way, the operation of the three-way valve 21 is controlled. Thereby, in the ejector type refrigeration cycle 10, the refrigerant flows as shown by the white arrow in FIG. 6, and the state of the refrigerant changes as shown in the Mollier diagram of FIG.

  More specifically, in the heating mode, the internal heat exchanger 19 exchanges heat between the high-pressure refrigerant flowing out of the indoor condenser 12 and the refrigerant decompressed by the indoor expansion valve 14. As a result, the high-pressure refrigerant flowing out of the indoor condenser 12 decreases enthalpy (b8 point → bα8 point in FIG. 8), and the refrigerant decompressed by the indoor expansion valve 14 increases enthalpy (in FIG. 8). c8 point → dα8 point), the dryness is increased.

  Other operations are the same as those in the first embodiment. Therefore, in the heating mode in which the three-way valve 21 opens the bypass passage 20, heating the blown air by the indoor condenser 12 can realize heating of the vehicle interior.

  Furthermore, in the ejector refrigeration cycle 10 in the heating mode, a cycle configuration in which the blown air is not cooled by the indoor evaporator 15 can be realized. Furthermore, since the ejector 16 is provided, a decrease in the COP of the ejector refrigeration cycle 10 can be suppressed as in the dehumidifying and heating mode.

  In addition, since the internal heat exchanger 19 is provided, even if the indoor evaporator 15 is switched to a cycle configuration in which the blown air is not cooled, the vapor phase refrigerant vaporized by the internal heat exchanger 19 or relatively A refrigerant having a high degree of dryness can flow into the nozzle portion 161.

  Accordingly, the energy conversion efficiency of the ejector 16 can be improved by increasing the flow rate of the injected refrigerant as compared with the case where the liquid-phase refrigerant is caused to flow into the nozzle portion 161. As a result, in the heating mode, the COP of the ejector refrigeration cycle 10 can be suppressed more effectively.

  In the Mollier diagram shown in FIG. 8, the refrigerant flowing into the nozzle part 161 in the heating mode is a gas-phase refrigerant, but the refrigerant flowing into the nozzle part 161 is a gas-liquid two-phase refrigerant having a relatively high dryness. Even if it is, the same COP improvement effect can be acquired.

(Fourth embodiment)
In this embodiment, an example in which the control mode of the ejector refrigeration cycle 10 of the first embodiment is changed will be described. More specifically, as shown in FIG. 9, the air conditioning control device 40 of the present embodiment includes an indoor evaporator pressure sensor that detects the pressure Pe <b> 1 of the outlet of the indoor evaporator 15 as a sensor group for air conditioning control. 57, an outdoor heat exchanger pressure sensor 58 for detecting the pressure Pe2 of the refrigerant on the outlet side of the outdoor heat exchanger 18 is connected.

  Other configurations of the ejector refrigeration cycle 10 and the vehicle air conditioner 1 are the same as those in the first embodiment.

  Furthermore, in the air-conditioning control program of the air-conditioning control device 40 of the present embodiment, the outdoor heat exchanger temperature Te2 and the outdoor heat are set for the throttle opening degree of the outdoor expansion valve 17 (control signal output to the outdoor expansion valve 17). Based on the pressure Pe2 of the refrigerant on the outlet side of the exchanger 18, it is determined with reference to a control map stored in the air conditioning controller 40 in advance.

  Specifically, in this control map, the deviation obtained by subtracting the outside air temperature Tam from the outdoor heat exchanger temperature Te2 within the range where the refrigerant flowing out from the outdoor heat exchanger 18 is in a gas-liquid two-phase state is the standard deviation (this embodiment). In the form, it is determined to be 10 ° C.

  Further, the throttle opening degree of the indoor expansion valve 14 (control signal output to the indoor expansion valve 14) is a feedback control method based on the indoor evaporator temperature Te1 and the pressure Pe1 of the indoor evaporator 15 outlet side refrigerant. Thus, the indoor evaporator temperature Te1 is determined to be the reference evaporation temperature KTe1 (15 ° C. in the present embodiment) in a range where the refrigerant flowing out of the indoor evaporator 15 is in a gas phase state having a superheat degree. .

  Other operations of the ejector refrigeration cycle 10 and the vehicle air conditioner 1 are the same as those in the first embodiment. Therefore, in the ejector refrigeration cycle 10 of the present embodiment, the state of the refrigerant changes as shown in the Mollier diagram of FIG.

  More specifically, the refrigerant depressurized by the indoor expansion valve 14 (point c10 in FIG. 10) absorbs heat from the blown air in the indoor evaporator 15, and becomes enthalpy until it becomes a superheated gas phase refrigerant. (C10 point in FIG. 10 → d10 point). Thereby, blowing air is cooled and dehumidified. Further, the refrigerant decompressed by the outdoor expansion valve 17 (point h10 in FIG. 10) absorbs heat from the outside air in the outdoor heat exchanger 18 and becomes a gas-liquid two-phase state (point h10 → i10 point in FIG. 10). ).

  Other operations are the same as those in the first embodiment. Therefore, in the vehicle air conditioner 1 of the present embodiment, dehumidifying heating in the passenger compartment can be realized as in the first embodiment. Furthermore, also in the ejector refrigeration cycle 10 of the present embodiment, it is possible to suppress a decrease in COP of a refrigeration cycle apparatus including a plurality of heat exchangers as in the first embodiment.

  In addition, in the ejector refrigeration cycle 10 of the present embodiment, the throttle opening of the outdoor expansion valve 17 is changed so that the refrigerant flowing out of the outdoor heat exchanger 18 is in a gas-liquid two-phase state. Thereby, the pressure loss at the time of a refrigerant | coolant distribute | circulating the outdoor heat exchanger 18 can be reduced rather than the case where the refrigerant | coolant which flows out from the outdoor heat exchanger 18 will be in a gaseous-phase state. Therefore, the power consumption of the compressor 11 can be reduced, and the reduction of the COP of the ejector refrigeration cycle 10 can be suppressed more effectively.

  Further, the throttle opening degree of the indoor expansion valve 14 is changed so that the refrigerant flowing out of the indoor evaporator 15 is in a gas phase state having a superheat degree. Thereby, even if the refrigerant | coolant which flows out from the outdoor heat exchanger 18 is a gas-liquid two-phase state, the refrigerant | coolant which flows out from the refrigerant | coolant outflow port of the ejector 16 can be made into a gaseous-phase state. Therefore, liquid compression of the compressor 11 can be suppressed, and the reliability of the compressor 11 can be improved.

(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. Further, the means disclosed in each of the above embodiments may be appropriately combined within a practicable range. For example, the ejector 26 described in the second embodiment may be applied to the ejector refrigeration cycle 10 of the third and fourth embodiments.

  (1) In the above-described embodiment, the example in which the ejector refrigeration cycle 10 according to the present invention is applied to the vehicle air conditioner 1 for an electric vehicle has been described. However, the application of the ejector refrigeration cycle 10 is not limited thereto. For example, the present invention may be applied to a hybrid vehicle that obtains driving force for vehicle travel from both the travel electric motor and the engine, a diesel vehicle that has little engine waste heat, and the like. Of course, the ejector refrigeration cycle 10 may be applied to a stationary heating device or the like.

  Further, a cooling device for switching the refrigerant circuit and a cooling decompression device may be added to the ejector-type refrigeration cycle 10 to realize cooling in the passenger compartment. Specifically, during the cooling operation, the refrigerant circuit may be switched to the refrigerant circuit in the order of the compressor 11 → the outdoor heat exchanger 18 → the pressure reducing device for cooling → the indoor evaporator 15 → the compressor 11.

  (2) In the above-described embodiment, the drive unit 164 of the ejector 16 forms a sealed space in which the temperature sensitive medium is enclosed together with the diaphragm 164a, which is a pressure responsive member that is displaced according to the pressure of the temperature sensitive medium, and the diaphragm 164a. Although the example which employ | adopted the mechanical mechanism which has the cover member 164b which is an enclosure space formation member was demonstrated, a drive part is not limited to this. For example, an electric mechanism such as an electric motor or a solenoid may be employed to displace the valve body 163 (needle valve 163a).

  Further, in the above-described embodiment, the example in which the valve body portion 163 (needle valve 163a) that is displaced inside the ejector 16 is formed of resin for weight reduction is described. Of course, the valve body portion 163 (needle valve 163a) is formed. ) May be formed of metal. Further, the body 160, the nozzle 161, the diffuser body 162, and the like have been described as being formed of metal, but the material is not limited as long as the functions of the respective constituent members can be exhibited. That is, you may form these structural members with resin.

  (3) In the above embodiment, the example in which the reference evaporation temperature KTe1 is set to 15 ° C. has been described. However, the reference evaporation temperature KTe1 is not limited to this. The indoor evaporator 15 can dehumidify the blown air, and the temperature at which frosting of the indoor evaporator 15 can be suppressed can be set as appropriate.

  (4) In the above-described third embodiment, the example in which the three-way valve 21 is employed as the opening / closing device that opens and closes the bypass passage 20 has been described. However, the opening / closing device is not limited thereto. For example, an open / close valve (solenoid valve) that opens and closes the bypass passage 20 may be employed as the open / close device. Even in such a configuration, the refrigerant circuit can be switched by setting the passage resistance of the bypass passage when the on-off valve is opened and the refrigerant flows to be sufficiently lower than the passage resistance of the indoor evaporator 15. it can.

  (5) In the above-described fourth embodiment, in order to control the operation of the indoor expansion valve 14 and the outdoor expansion valve 17, an indoor evaporator temperature sensor 54, an outdoor heat exchanger temperature sensor 55, an indoor evaporator pressure sensor 57. Although the example using the detection signal of the outdoor heat exchanger pressure sensor 58 has been described, the detection signal is not limited to this.

  For example, a superheat degree sensor that detects the superheat degree of the refrigerant on the outlet side of the indoor evaporator 15 may be added, and the operation of the indoor expansion valve 14 may be controlled based on the detection signal of the superheat degree sensor. Further, a dryness sensor that detects the dryness of the refrigerant on the outlet side of the outdoor heat exchanger 18 may be added, and the operation of the outdoor expansion valve 17 may be controlled based on the detection signal of the dryness sensor.

  (6) In the above-described embodiment, it has been described that R134a or R1234yf or the like can be adopted as the refrigerant, but the refrigerant is not limited to this. For example, R600a, R410A, R404A, R32, R407C, HFO-1234ze, HFO-1234zd, and the like can be employed. Or you may employ | adopt the mixed refrigerant | coolant etc. which mixed multiple types among these refrigerant | coolants.

10 Ejector refrigeration cycle 11 Compressor 12 Indoor condenser (heat radiator)
13 branch part 14 indoor expansion valve (first decompression device)
15 Indoor evaporator 16 Ejector 17 Outdoor expansion valve (second decompression device)
18 Outdoor heat exchanger 19 Internal heat exchanger 20 Bypass passage 21 Three-way valve (switching device)

Claims (3)

A refrigeration cycle apparatus applied to an air conditioner that adjusts the temperature of blown air that is blown into an air conditioning target space,
A compressor (11) for compressing and discharging the refrigerant;
A radiator (12) for radiating the refrigerant discharged from the compressor (11);
A branch part (13) for branching the flow of the refrigerant flowing out of the radiator (12);
A first pressure reducing device (14) for depressurizing one of the refrigerants branched at the branching portion (13);
A second decompression device (17) for decompressing the other refrigerant branched at the branch portion (13);
An indoor evaporator (15) for evaporating the refrigerant decompressed by the first decompression device (14) by exchanging heat with the blown air;
An outdoor heat exchanger (18) for heat-exchanging the refrigerant decompressed by the second decompression device (17) with the outside air to evaporate;
Heat the high-pressure side refrigerant flowing through the refrigerant flow path from the outlet side of the radiator (12) to the inlet side of the branch portion (13) and the low-pressure side refrigerant decompressed by the first decompression device (14). An internal heat exchanger (19) to be exchanged;
The outdoor heat exchanger (18) is connected to the outdoor heat exchanger (18) from the refrigerant suction port (16a) by the suction action of the high-speed jet refrigerant injected from the nozzle portion (161) for depressurizing the low-pressure side refrigerant flowing out of the internal heat exchanger (19). An ejector (16) having a boosting section (16c) for sucking the downstream refrigerant and mixing and injecting the jet refrigerant and the suction refrigerant sucked from the refrigerant suction port (16a);
A bypass passage (20) for guiding the refrigerant flowing out of the first decompression device (14) to the indoor evaporator (15) and leading to the inlet side of the internal heat exchanger (19);
An opening and closing device (21) for opening and closing the bypass passage (20),
The refrigerant outlet of the booster (16c) is connected to the inlet side of the compressor (11). The first pressure reducing device (14) is configured to be able to change the throttle opening,
Furthermore, a first pressure reduction control unit (40b) for controlling the operation of the first pressure reduction device (14) is provided,
The first depressurization control unit (40b) is configured to restrict the opening degree of the first depressurization device (14) so that the refrigerant evaporating temperature in the indoor evaporator (15) approaches a predetermined reference evaporating temperature (KTe1). The refrigeration cycle apparatus according to claim 1 , wherein the refrigeration cycle apparatus is changed. A refrigeration cycle apparatus applied to an air conditioner that adjusts the temperature of blown air that is blown into an air conditioning target space,
A compressor (11) for compressing and discharging the refrigerant;
A radiator (12) for radiating the refrigerant discharged from the compressor (11);
A branch part (13) for branching the flow of the refrigerant flowing out of the radiator (12);
A first pressure reducing device (14) configured to change a throttle opening for depressurizing one of the refrigerants branched at the branching portion (13);
A second pressure reducing device (17) configured to be able to change a throttle opening for depressurizing the other refrigerant branched in the branch portion (13);
An indoor evaporator (15) for evaporating the refrigerant decompressed by the first decompression device (14) by exchanging heat with the blown air;
An outdoor heat exchanger (18) for heat-exchanging the refrigerant decompressed by the second decompression device (17) with the outside air to evaporate;
The outdoor heat exchanger (18) downstream refrigerant is discharged from the refrigerant suction port (16a) by the suction action of the high-speed jet refrigerant injected from the nozzle part (161) for depressurizing the downstream refrigerant in the indoor evaporator (15). An ejector (16) having a boosting part (16c) that sucks and mixes the jetted refrigerant and the suctioned refrigerant sucked from the refrigerant suction port (16a) to increase the pressure;
A first pressure reduction control unit (40b) for controlling the operation of the first pressure reduction device (14);
A second pressure reduction control unit (40c) for controlling the operation of the second pressure reduction device (17),
The refrigerant outlet of the pressurizing unit (16c) is connected to the inlet side of the compressor (11),
The first pressure reduction control unit (40b) changes the throttle opening of the first pressure reduction device (14) so that the refrigerant flowing out of the indoor evaporator (15) is in a gas phase state having a superheat degree. ,
The second pressure reduction control unit (40c) changes the throttle opening of the second pressure reduction device (17) so that the refrigerant flowing out of the outdoor heat exchanger (18) is in a gas-liquid two-phase state. A refrigeration cycle apparatus characterized by.

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