JP2019138614A - Ejector-type refrigeration cycle and flow rate regulation valve - Google Patents

Abstract

To provide an ejector-type refrigeration cycle which can properly regulate a flow rate of a refrigerant flowing into a suction-side evaporator irrespective of a variation of a load.SOLUTION: A suction-side decompression device 15 for decompressing a refrigerant flowing into a suction-side evaporator 19 employs a thermostatic expansion valve for changing a throttle opening so that an overheat degree SH1 of the refrigerant at an outlet side of the suction-side evaporator 19 approximates a reference overheat degree KSH1, and also comprises a bypass passage 16 for introducing the refrigerant at an inlet side of the suction-side decompression device 15 to an inlet side of the suction-side evaporator 19 by making it bypass the suction-side decompression device 15, and a variable throttle device 17 having a function for opening and closing the bypass passage 16. When a flow rate Ge1 of the refrigerant flowing out of the suction-side decompression device 15 reaches a reference flow rate KGe1 or smaller, the variable throttle device 17 opens the bypass passage 16.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an ejector refrigeration cycle including an ejector, and a flow rate adjusting valve applied to the ejector refrigeration cycle.

  2. Description of the Related Art Conventionally, an ejector refrigeration cycle that is a vapor compression refrigeration cycle including an ejector is known. In this type of ejector refrigeration cycle, the pressure of the refrigerant sucked into the compressor can be increased by the pressure increasing action of the diffuser portion of the ejector. Thereby, in the ejector type refrigeration cycle, the power consumption of the compressor can be reduced and the coefficient of performance (COP) of the cycle can be improved.

  For example, Patent Document 1 discloses an ejector-type refrigeration cycle that is applied to an air conditioner and cools blown air that is blown into an air-conditioning target space.

  More specifically, the ejector refrigeration cycle of Patent Document 1 includes a branching portion that branches the flow of the high-pressure refrigerant that has flowed out of the radiator, and a suction-side evaporator that evaporates the low-pressure refrigerant and cools the blown air. Yes. Then, 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 depressurized by the suction side decompression portion and flows into the suction side evaporator. Further, the refrigerant has a cycle configuration in which the refrigerant flowing out from the suction side evaporator is sucked from the refrigerant suction port of the ejector.

  Patent Document 1 employs a temperature expansion valve that adjusts the throttle opening degree so that the superheat degree of the refrigerant on the outlet side of the suction side evaporator approaches a predetermined reference superheat degree as the suction side pressure reducing unit. Examples are also disclosed.

Japanese Patent No. 5217121

  By the way, by adjusting the throttle opening degree of the suction side decompression unit as in Patent Document 1, the refrigerant sucked from the refrigerant suction port of the ejector can be reliably made into a gas phase refrigerant having a superheat degree. According to this, it can suppress that the flow volume (mass flow rate) of the refrigerant | coolant suck | inhaled from a refrigerant | coolant suction port increases unnecessarily, and can suppress the fall of the pressure | voltage rise amount in a diffuser part. That is, a decrease in cycle COP can be suppressed.

  However, at the time of low load operation or the like, the flow rate of the refrigerant flowing into the suction side evaporator decreases, so the temperature distribution of the blown air cooled by the suction side evaporator sometimes expands. . That is, even if the throttle opening degree of the suction side pressure reducing unit is adjusted so that the superheat degree of the refrigerant on the outlet side of the suction side evaporator approaches a predetermined reference superheat degree as in Patent Document 1, cycle load fluctuation Accordingly, the flow rate of the refrigerant flowing into the suction side evaporator cannot be adjusted appropriately.

  In view of the above points, an object of the present invention is to provide an ejector refrigeration cycle in which the flow rate of the refrigerant flowing into the suction side evaporator can be appropriately adjusted.

  Another object of the present invention is to provide a flow rate adjusting valve capable of appropriately adjusting the flow rate of the refrigerant flowing into the suction side evaporator when applied to an ejector refrigeration cycle.

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 radiator. The refrigerant is sucked from the refrigerant suction port (14c) by the suction action of the jetted refrigerant jetted from the nozzle part (14a) for depressurizing the refrigerant that has flowed out. An ejector (14) for increasing the pressure, a suction side pressure reducing part (15) for reducing the pressure of the refrigerant, and a suction side evaporator (19) for evaporating the refrigerant depressurized by the suction side pressure reducing part to flow out to the refrigerant suction port side; A bypass passage (16) for guiding the refrigerant on the inlet side of the suction side pressure reducing section to the inlet side of the suction side evaporator by bypassing the suction side pressure reducing section, and a variable throttle mechanism for adjusting the flow rate of the refrigerant flowing through the bypass passage Part (17) ,
The suction side decompression unit changes the throttle opening so that the degree of superheat (SH1) of the refrigerant on the outlet side of the suction side evaporator approaches a predetermined reference superheat degree (KSH1),
The variable throttle mechanism has a function of opening and closing the bypass passage, and opens the bypass passage when the flow rate (Ge1) of the refrigerant flowing out from the suction-side decompression portion is equal to or lower than a predetermined reference flow rate (KGe1). This is an ejector refrigeration cycle.

  According to this, the variable throttle mechanism (17) is bypassed under the operating condition in which the flow rate (Ge1) of the refrigerant flowing out from the suction side pressure reducing unit (15) is larger than the reference flow rate (KGe1) as in normal operation. Close the passage (16). Thereby, the refrigerant decompressed by the suction side decompression unit (15) can flow into the suction side evaporator (19).

  Therefore, under the operating conditions in which the flow rate of the refrigerant flowing into the suction-side evaporator (19) is relatively large, the suction-side decompression section (15) changes the throttle opening so that the outlet of the suction-side evaporator (19). The flow rate of the refrigerant flowing into the suction side evaporator (19) can be appropriately adjusted so that the superheat degree of the refrigerant on the side approaches the reference superheat degree.

  On the other hand, the variable throttle mechanism (17) is bypassed under the operating condition where the flow rate (Ge1) of the refrigerant flowing out from the suction side pressure reducing unit (15) is equal to or less than the reference flow rate (KGe1) as in the low load operation. Open the passage (16). Thereby, the refrigerant | coolant by the side of an inlet_port | entrance of a suction side pressure reduction part (15) can be made to flow into a suction side evaporator (19) via a bypass channel | path (16).

  Therefore, under the operating conditions where the flow rate of the refrigerant flowing into the suction-side evaporator (19) is relatively small, the suction-side decompression section (15) has passed through the bypass passage (16) even if the throttle opening is decreased. The refrigerant can surely flow into the suction side evaporator (19). Thereby, it can suppress that the flow volume of the refrigerant | coolant which flows in into a suction side evaporator (19) runs short.

  That is, according to the first aspect of the present invention, it is possible to provide an ejector-type refrigeration cycle in which the flow rate of the refrigerant flowing into the suction side evaporator (19) can be appropriately adjusted according to cycle load fluctuations. .

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 ejector (14) sucks the refrigerant from the refrigerant suction port (14c) by the suction action of the jetted refrigerant jetted from the nozzle section (14a) to be pressurized, and boosts the mixed refrigerant of the jetted refrigerant and the suction refrigerant sucked from the refrigerant suction port. ), A suction side decompression unit (15) for decompressing the refrigerant, a suction side evaporator (19) for evaporating the refrigerant decompressed by the suction side decompression unit and flowing it out to the refrigerant suction port side, and a suction side decompression unit A bypass passage (16) for guiding the refrigerant on the inlet side to the inlet side of the suction-side evaporator, bypassing the suction-side decompression unit,
The suction-side decompression unit is responsive to the enclosed space (52c) in which the temperature-sensitive medium whose pressure changes with the change in temperature of the refrigerant on the outlet side of the suction-side evaporator is enclosed, and the pressure of the temperature-sensitive medium in the enclosed space It has a throttle valve (51) that displaces, and changes the throttle opening so that the superheat degree (SH1) of the refrigerant on the outlet side of the suction side evaporator approaches a predetermined reference superheat degree (KSH1),
A value obtained by subtracting the saturation pressure of the temperature sensitive medium at a predetermined reference medium temperature from the outlet side pressure, which is the pressure of the refrigerant flowing out from the suction side evaporator, is defined as the valve opening set pressure (Y), When the ratio (Apt / Aex) of the minimum passage sectional area (Apt) of the bypass passage to the maximum passage sectional area (Aex) is defined as an area ratio X,
-170X + 3 ≧ Y
And,
Y ≧ −350X-9
This is an ejector type refrigeration cycle.

  According to this, both the refrigerant decompressed by the suction side decompression section (15) and the refrigerant that has passed through the bypass passage (16) can flow into the suction side evaporator (19).

  Then, under the operating condition in which the flow rate of the refrigerant flowing into the suction side evaporator (19) is relatively large as in the normal operation, the suction side pressure reducing unit (15) increases the throttle opening. For this reason, the ratio of the flow volume of the refrigerant | coolant which flows into a suction side evaporator (19) via a suction side decompression part (15) among the flow volume of the refrigerant | coolant which flows into a suction side evaporator (19) increases.

  Therefore, under the operating conditions in which the flow rate of the refrigerant flowing into the suction-side evaporator (19) is relatively large, the suction-side decompression section (15) changes the throttle opening so that the outlet of the suction-side evaporator (19). The flow rate of the refrigerant flowing into the suction side evaporator (19) can be appropriately adjusted so that the superheat degree of the refrigerant on the side approaches the reference superheat degree.

  On the other hand, the suction-side decompression unit (15) decreases the throttle opening when the operating condition is such that the flow rate of the refrigerant flowing into the suction-side evaporator (19) is relatively small, such as during low-load operation. For this reason, the ratio of the flow volume of the refrigerant | coolant which passed the bypass channel | path (16) among the flow volume of the refrigerant | coolant which flows in into a suction side evaporator (19) increases.

  Therefore, under the operating conditions where the flow rate of the refrigerant flowing into the suction-side evaporator (19) is relatively small, the suction-side decompression section (15) has passed through the bypass passage (16) even if the throttle opening is decreased. The refrigerant can surely flow into the suction side evaporator (19). Thereby, it can suppress that the flow volume of the refrigerant | coolant which flows in into a suction side evaporator (19) runs short.

  That is, according to the invention described in claim 4, it is possible to provide an ejector refrigeration cycle in which the flow rate of the refrigerant flowing into the suction side evaporator (19) can be appropriately adjusted according to cycle load fluctuations. .

In the invention according to claim 6, the refrigerant is sucked from the refrigerant suction port (14c) by the suction action of the jet refrigerant injected from the nozzle part (14a) for depressurizing the refrigerant, and sucked from the jet refrigerant and the refrigerant suction port. The present invention is applied to an ejector refrigeration cycle (10, 10a) having an ejector (14) for raising the pressure of a mixed refrigerant with the drawn suction refrigerant, and a suction side evaporator (19) for evaporating the refrigerant to flow out to the refrigerant suction port side. A flow regulating valve,
A suction side pressure reducing part (15) for changing the throttle opening so that the superheat degree (SH1) of the refrigerant on the outlet side of the suction side evaporator approaches a predetermined reference superheat degree (KSH1), and an inlet of the suction side pressure reducing part A bypass passage (16) for bypassing the refrigerant on the suction side to the outlet side of the suction side decompression portion by bypassing the suction side decompression portion, and a variable throttle mechanism portion (17) for adjusting the flow rate of the refrigerant flowing through the bypass passage, Prepared,
A refrigerant inlet side of the suction-side evaporator is connected to the evaporator-side outlet (21b) through which the refrigerant decompressed by the suction-side decompression unit flows out.
The variable throttle mechanism has a function of opening and closing the bypass passage, and the flow rate (Ge1) of the refrigerant flowing out from the suction side decompression unit to the refrigerant inlet side of the suction side evaporator is equal to or less than a predetermined reference flow rate (KGe1). It is a flow control valve that opens the bypass passage when

  According to this, the operation in which the flow rate (Ge1) of the refrigerant flowing out from the suction-side decompression unit (15) is larger than the reference flow rate (KGe1) as in the normal operation of the applied ejector refrigeration cycle (10, 10a). When the condition is met, the variable throttle mechanism (17) closes the bypass passage (16). Thereby, the refrigerant decompressed by the suction side decompression unit (15) can flow out to the suction side evaporator (19) side.

  Therefore, when the applied ejector-type refrigeration cycle (10, 10a) has an operating condition in which a relatively large amount of refrigerant flows into the suction-side evaporator (19), the suction-side decompression section (15) By changing the throttle opening, the flow rate of the refrigerant flowing into the suction side evaporator (19) is appropriately adjusted so that the superheat degree of the refrigerant on the outlet side of the suction side evaporator (19) approaches the reference superheat degree. Can be adjusted.

  On the other hand, the operating condition is such that the flow rate (Ge1) of the refrigerant flowing out from the suction side pressure reducing unit (15) is equal to or less than the reference flow rate (KGe1) as in the applied ejector refrigeration cycle (10, 10a) during low load operation. The variable throttle mechanism (17) opens the bypass passage (16). Thereby, the refrigerant | coolant of the inlet side of a suction side pressure reduction part (15) can be flowed out to the suction side evaporator (19) side via a bypass channel | path (16).

  Therefore, when the applied ejector-type refrigeration cycle (10, 10a) has an operating condition in which a relatively small flow rate of refrigerant flows into the suction-side evaporator (19), the suction-side decompression unit (15) Even if the throttle opening is reduced, the refrigerant that has passed through the bypass passage (16) can surely flow into the suction-side evaporator (19). Thereby, it can suppress that the flow volume of the refrigerant | coolant which flows in into a suction side evaporator (19) runs short.

  That is, according to the sixth aspect of the present invention, when applied to the ejector refrigeration cycle (10, 10a), the flow rate of the refrigerant flowing into the suction-side evaporator (19) according to cycle load fluctuations. It is possible to provide a flow rate adjustment valve that can be adjusted appropriately.

According to the ninth aspect of the present invention, the refrigerant is sucked from the refrigerant suction port (14c) by the suction action of the jetted refrigerant injected from the nozzle portion (14a) for decompressing the refrigerant, and sucked from the jetted refrigerant and the refrigerant suction port. The present invention is applied to an ejector refrigeration cycle (10, 10a) having an ejector (14) for raising the pressure of a mixed refrigerant with the drawn suction refrigerant, and a suction side evaporator (19) for evaporating the refrigerant to flow out to the refrigerant suction port side. A flow regulating valve,
A suction side pressure reducing part (15) for changing the throttle opening so that the superheat degree (SH1) of the refrigerant on the outlet side of the suction side evaporator approaches a predetermined reference superheat degree (KSH1), and an inlet of the suction side pressure reducing part A bypass passage (16) for guiding the refrigerant on the side to the outlet side of the suction side decompression unit by bypassing the suction side decompression unit,
The suction-side decompression unit includes a sealed space (52c) in which a temperature-sensitive medium whose pressure changes with a change in temperature of the refrigerant on the outlet side of the suction-side evaporator is enclosed, and a throttle valve that is displaced according to the pressure of the temperature-sensitive medium. (51), the refrigerant outlet side of the suction side evaporator is connected to the evaporator side outlet (21b) through which the refrigerant decompressed by the suction side decompression unit flows out,
A value obtained by subtracting the saturation pressure of the temperature sensitive medium at a predetermined reference medium temperature from the outlet side pressure, which is the pressure of the refrigerant flowing out from the suction side evaporator, is defined as the valve opening set pressure (Y), When the ratio (Apt / Aex) of the minimum passage sectional area (Apt) of the bypass passage to the maximum passage sectional area (Aex) is defined as an area ratio X,
-170X + 3 ≧ Y
And,
Y ≧ −350X-9
This is a flow rate adjustment valve.

  According to this, both the refrigerant decompressed by the suction-side decompression unit (15) and the refrigerant that has passed through the bypass passage (16) can flow out to the refrigerant inlet side of the suction-side evaporator (19).

  Then, when the applied ejector refrigeration cycle (10, 10a) is in an operating condition in which a relatively large amount of refrigerant flows into the suction side evaporator (19) as in normal operation, suction is performed. The side pressure reducing unit (15) increases the throttle opening. For this reason, the ratio of the flow rate of the refrigerant flowing out to the refrigerant inlet side of the suction side evaporator (19) via the suction side decompression unit (15) out of the flow rate of the refrigerant flowing out to the suction side evaporator (19) side is To increase.

  Therefore, when the applied ejector-type refrigeration cycle (10, 10a) has an operating condition in which a relatively large amount of refrigerant flows into the suction-side evaporator (19), the suction-side decompression unit (15 ) Changes the throttle opening so that the flow rate of the refrigerant flowing into the suction side evaporator (19) is appropriately adjusted so that the superheat degree of the refrigerant on the outlet side of the suction side evaporator (19) approaches the reference superheat degree. Can be adjusted.

  On the other hand, the applied ejector-type refrigeration cycle (10, 10a) has an operating condition in which a relatively small amount of refrigerant flows from the suction-side decompression unit (15) to the suction-side evaporator (19) as in low-load operation. When it is, the suction side pressure reducing part (15) decreases the throttle opening. For this reason, the ratio of the flow volume of the refrigerant | coolant which passed through the bypass channel | path (16) among the flow volume of the refrigerant | coolant made to flow out to the suction side evaporator (19) side increases.

  Therefore, when the applied ejector-type refrigeration cycle (10, 10a) has an operating condition in which a relatively small amount of refrigerant flows into the suction-side evaporator (19), the suction-side decompression unit (15) However, even if the throttle opening is reduced, the refrigerant that has passed through the bypass passage (16) can surely flow into the suction-side evaporator (19). Thereby, it can suppress that the flow volume of the refrigerant | coolant which flows in into a suction side evaporator (19) runs short.

  That is, according to the ninth aspect of the present invention, when applied to the ejector refrigeration cycle (10, 10a), the flow rate of the refrigerant flowing into the suction side evaporator (19) in accordance with the load fluctuation of the cycle. It is possible to provide a flow rate adjustment valve that can be adjusted appropriately.

  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 typical sectional drawing at the time of the flow regulating valve of a 1st embodiment making a bypass passage fully closed. It is a typical sectional view at the time of the flow regulating valve of a 1st embodiment making a bypass passage the throttling state. It is typical sectional drawing when the flow regulating valve of a 1st embodiment has made a bypass passage into a full open state. It is a typical sectional view at the time of the flow regulating valve of a 2nd embodiment making a bypass passage fully open. It is typical sectional drawing at the time of the flow regulating valve of a 3rd embodiment making a bypass passage fully open. It is typical sectional drawing of the flow regulating valve of 4th Embodiment. It is explanatory drawing for demonstrating the measuring method of the valve opening setting pressure of 4th Embodiment. It is a graph which shows the relationship between the area ratio of 4th Embodiment, and valve-opening setting pressure. It is typical sectional drawing of the flow regulating valve of the modification of 4th Embodiment. It is a whole block diagram of the ejector-type refrigerating cycle of 5th Embodiment. It is a whole block diagram of the ejector-type refrigerating cycle of 6th Embodiment. It is a whole block diagram of the ejector type refrigerating cycle of 7th 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 fluid to be cooled in the ejector refrigeration cycle 10 is blown air.

  The ejector refrigeration cycle 10 employs an HFO refrigerant (specifically, R1234yf) 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 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 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 the compression mechanism, various compression mechanisms such as a scroll-type compression mechanism and a vane-type compression mechanism can be employed. 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 40, and any type of an AC motor or a DC motor can be adopted. Good.

  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 condensing 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 condense it. The cooling fan 12 a is an electric blower in which the rotation speed (the amount of blown air) is controlled by a control voltage output from the air conditioning control device 40.

  The refrigerant outlet of the 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. The branch part 13 has a three-way joint structure having three refrigerant inlets and outlets communicating with each other, one of the three refrigerant inlets and outlets being a refrigerant inlet and the other two being refrigerant outlets. .

  One refrigerant outlet of the branch part 13 is connected to the inlet side of the nozzle part 14 a of the ejector 14. The other refrigerant outlet of the branch part 13 is connected to the refrigerant inlet 21 a side formed in the body part 21 of the flow rate adjusting valve 20.

  The ejector 14 has a nozzle part 14a that decompresses and injects the refrigerant that has flowed out of the radiator 12, and functions as a refrigerant decompression part. Further, the ejector 14 functions as a refrigerant circulation section that sucks and circulates the refrigerant from the outside by the suction action of the refrigerant injected from the refrigerant injection port of the nozzle portion 14a.

  In addition to this, the ejector 14 converts the kinetic energy of the mixed refrigerant of the refrigerant injected from the nozzle portion 14a and the suction refrigerant sucked from the refrigerant suction port 14c into pressure energy, and increases the pressure of the mixed refrigerant. It fulfills the function as a part.

  More specifically, the ejector 14 has a nozzle portion 14a and a body portion 14b. The nozzle portion 14a is formed of a substantially cylindrical metal (stainless alloy in the present embodiment) that gradually tapers in the refrigerant flow direction. The nozzle part 14a is an isentropic decompression of the refrigerant in the refrigerant passage formed inside.

  The refrigerant passage formed in the nozzle portion 14a 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 part 14a of this embodiment is configured as a Laval nozzle.

  Further, in the present embodiment, the nozzle portion 14a 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 14a with a tapered nozzle.

  The body portion 14b is formed of a substantially cylindrical metal (in this embodiment, aluminum). The body portion 14b functions as a fixing member that supports and fixes the nozzle portion 14a therein and forms an outer shell of the ejector 14. More specifically, the nozzle portion 14a is fixed by press-fitting so as to be housed inside the longitudinal end of the body portion 14b. The body part 14b may be formed of resin.

  Of the outer peripheral surface of the body portion 14b, a portion corresponding to the outer peripheral side of the nozzle portion 14a is formed with a refrigerant suction port 14c provided so as to penetrate the inside and the outside and communicate with the refrigerant injection port of the nozzle portion 14a. ing. The refrigerant suction port 14c is a through hole that sucks the refrigerant that has flowed out from a suction side evaporator 19 described later into the ejector 14 by the suction action of the jet refrigerant injected from the nozzle portion 14a.

  A suction passage and a diffuser portion 14d are formed inside the body portion 14b. The suction passage is a refrigerant passage that guides the suction refrigerant sucked from the refrigerant suction port 14c to the refrigerant injection port side of the nozzle portion 14a. The diffuser unit 14d is a pressure increasing unit that increases the pressure by mixing the suction refrigerant and the injection refrigerant.

  The suction passage is formed in a space between the outer peripheral side around the tapered tip of the nozzle portion 14a and the inner peripheral side of the body portion 14b, and the refrigerant passage area of the suction passage is directed toward the refrigerant flow direction. It is gradually shrinking. Thereby, the flow rate of the suction refrigerant flowing through the suction passage is gradually increased to reduce energy loss (so-called mixing loss) when the suction refrigerant and the injection refrigerant are mixed in the diffuser portion 14d.

  The diffuser portion 14d is a portion where a refrigerant passage extending in a truncated cone shape is formed so as to be continuous with the outlet of the suction passage. In the diffuser portion 14d, the passage cross-sectional area gradually increases toward the downstream side of the refrigerant flow. The diffuser part 14d 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 14b that forms the diffuser portion 14d 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 14d 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 14d. The outflow side evaporator 18 exchanges heat between the refrigerant flowing out from the diffuser portion 14d and the blown air blown from the indoor blower 18a toward the vehicle interior, evaporating the refrigerant and exerting an endothermic effect, thereby generating blown air. It is a heat exchanger for endothermic cooling.

  The indoor 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 40. Furthermore, the suction port side of the compressor 11 is connected to the refrigerant outlet side of the outflow side evaporator 18.

  Next, the flow rate adjustment valve 20 will be described. The flow rate adjustment valve 20 is an integrated (in other words, modularized) cycle component device surrounded by a broken line in FIG. More specifically, the flow rate adjusting valve 20 is an integrated unit of the suction side pressure reducing device 15, the bypass passage 16, the variable throttle device 17, and the like.

  The suction-side decompression device 15 is a suction-side decompression unit that decompresses the other refrigerant branched by the branching unit 13 until it becomes a low-pressure refrigerant. The suction-side decompression device 15 is a variable throttle configured to be able to change the passage cross-sectional area (that is, the throttle opening) of the throttle passage 20a that decompresses the refrigerant. The suction side decompression device 15 causes the decompressed refrigerant to flow out to the refrigerant inlet side of the suction side evaporator 19 described later.

  The bypass passage 16 bypasses the refrigerant on the inlet side of the suction-side decompression device 15 (more specifically, the throttle passage 20a) by bypassing the suction-side decompression device 15, and more specifically, the suction-side decompression device 15 (more specifically, This is a refrigerant passage that leads to the outlet side of the throttle passage 20a) (in other words, the refrigerant inlet side of the suction-side evaporator 19).

  The variable throttle device 17 is a variable throttle mechanism that adjusts the flow rate of the refrigerant flowing through the bypass passage 16 (specifically, the mass flow rate and other flow rates are the same). Furthermore, the variable throttle device 17 has a function of opening and closing the bypass passage 16. More specifically, the variable throttle device 17 opens the bypass passage 16 when the flow rate Ge1 of the refrigerant flowing out from the suction side pressure reducing device 15 is equal to or lower than a predetermined reference flow rate KGe1.

  The reference flow rate KGe1 is based on the temperature distribution of the blown air cooled by the suction side evaporator 19 when the variable throttle device 17 closes the bypass passage 16 and reduces the flow rate of the circulating refrigerant circulating in the cycle. It is set to a value that expands beyond the temperature difference.

  The temperature distribution of the blown air is defined by a temperature difference obtained by subtracting the lowest temperature from the highest temperature of the blown air immediately after being cooled by the suction side evaporator 19. Furthermore, the reference temperature difference is set to a value at which the occupant begins to feel uncomfortable due to the temperature distribution.

  The detailed configuration of the flow rate adjusting valve 20 will be described with reference to FIGS. The up and down arrows in FIGS. 2 to 4 indicate the up and down directions when the flow rate adjusting valve 20 is mounted on the vehicle.

  The flow rate adjustment valve 20 has a body portion 21. The body part 21 is formed by combining a plurality of constituent members made of metal (in this embodiment, made of aluminum). The body portion 21 forms an outer shell of the flow rate adjusting valve 20 and functions as a housing that accommodates some of the components such as the suction side pressure reducing device 15 and the variable throttle device 17 therein. The body part 21 may be formed of resin.

  Various coolant passages such as a bypass passage 16, a throttle passage 20 a, and a temperature sensing passage 20 b are formed inside the body portion 21. The outer surface of the body portion 21 is provided with a plurality of refrigerant inlets and outlets such as a refrigerant inlet 21a, an evaporator side outlet 21b, an evaporator side inlet 21c, and a low pressure outlet 21d.

  The other refrigerant outlet side of the branch part 13 is connected to the refrigerant inlet 21a. The refrigerant inlet 21 a is a refrigerant inlet through which the other refrigerant branched at the branching portion 13 flows. The refrigerant inlet 21 a communicates with the inlet side of the throttle passage 20 a of the suction side pressure reducing device 15 and the inlet side of the bypass passage 16 inside the body portion 21.

  The refrigerant inlet side of the suction side evaporator 19 is connected to the evaporator side outlet 21b. The evaporator side outlet 21 b is a refrigerant outlet through which the refrigerant decompressed by the suction side decompression device 15 and the refrigerant that has passed through the bypass passage 16 flow out to the refrigerant inlet side of the suction side evaporator 19. The refrigerant outlet side of the suction side evaporator 19 is connected to the evaporator side inlet 21c. The evaporator side inlet 21c is a refrigerant inlet through which the refrigerant flowing out from the suction side evaporator 19 flows into the temperature sensitive passage 20b.

  The refrigerant suction port 14c side of the ejector 14 is connected to the low pressure outlet 21d. The low-pressure outlet 21d is a refrigerant outlet through which the refrigerant flowing through the temperature-sensitive passage 20b flows out to the refrigerant suction port 14c side.

  The suction side pressure reducing device 15 includes a throttle passage 20a, a throttle valve 51, a drive mechanism 52, and the like. The throttle passage 20a is a refrigerant passage that depressurizes the other refrigerant branched at the branching portion 13 by reducing the passage cross-sectional area. The throttle passage 20a is formed in a rotating body shape such as a hemispherical shape or a truncated cone shape. The throttle passage 20a of the present embodiment is formed integrally with the body portion 21. Of course, the throttle passage 20a may be formed by fixing an orifice formed of a separate member to the body portion 21 to the body portion 21 by means such as press fitting.

  The throttle valve 51 is formed in a spherical shape, and changes the minimum passage cross-sectional area (that is, the throttle opening) of the throttle passage 20a by being displaced in the central axis direction of the throttle passage 20a. Furthermore, the throttle passage 20a can be closed by bringing the throttle valve 51 into contact with the outlet of the throttle passage 20a. The throttle valve 51 receives a load on the side for reducing the throttle opening of the throttle passage 20a from a coil spring 52e which is an elastic member.

  The drive mechanism 52 is a drive unit that displaces the throttle valve 51 in the central axis direction of the throttle passage 20a. The drive mechanism 52 is a mechanical mechanism. The drive mechanism 52 has a temperature sensing part 52a in which a diaphragm 52b, which is a deforming member that deforms in accordance with the temperature and pressure of the refrigerant flowing out from the suction side evaporator 19, is arranged. In the drive mechanism 52, the deformation of the diaphragm 52 b is transmitted to the throttle valve 51 via the operating rod 53, thereby displacing the throttle valve 51.

  The diaphragm 52b partitions the space formed in the temperature sensing part 52a into an enclosed space 52c and an introduction space 52d. In the enclosed space 52c, a temperature-sensitive medium whose pressure changes with a change in temperature is enclosed. In the present embodiment, the temperature-sensitive medium is mainly composed of a refrigerant circulating in the ejector refrigeration cycle 10.

  Furthermore, the temperature sensing part 52a is fixed to the body part 21 so that the introduction space 52d communicates with the temperature sensing passage 20b. For this reason, the pressure of the temperature sensitive medium in the enclosed space 52c changes according to the temperature of the refrigerant flowing through the temperature sensitive passage 20b (that is, the refrigerant flowing out of the suction side evaporator 19). And the diaphragm 52b deform | transforms according to the pressure difference of the pressure of the refrigerant | coolant which distribute | circulates the temperature sensing path 20b, and the pressure of the temperature sensitive medium in the enclosure space 52c.

  Therefore, it is desirable that the diaphragm 52b is formed of a material that is rich in elasticity and excellent in pressure resistance and airtightness. Therefore, in this embodiment, a circular metal thin plate made of stainless steel (specifically, SUS304) is employed as the diaphragm 52b. Of course, the diaphragm 52b may be made of rubber (eg, ethylene propylene diene rubber or hydrogenated nitrile rubber) containing a base fabric (eg, polyester).

  In the temperature sensing part 52a of this embodiment, when the temperature of the refrigerant flowing through the temperature sensing passage 20b (superheat degree) rises, the saturation pressure of the temperature sensing medium in the enclosed space 52c of the drive mechanism 52 rises, and the enclosed space The pressure difference between the pressure of the refrigerant flowing through the temperature sensing passage 20b increases from the pressure of the temperature sensing medium in 52c. As a result, when the diaphragm 52b is deformed, the throttle valve 51 is displaced to the side that increases the throttle opening of the throttle passage 20a.

  On the other hand, when the temperature (superheat degree) of the low-pressure refrigerant flowing through the temperature sensing passage 20b is lowered, the saturation pressure of the temperature sensing medium in the enclosed space 52c is lowered, and the temperature sensing is performed from the pressure of the temperature sensing medium in the enclosed space 52c. The pressure difference between the pressures of the low-pressure refrigerant flowing through the passage 20b is reduced. As a result, when the diaphragm 52b is deformed, the throttle valve 51 is displaced to the side that reduces the throttle opening of the throttle passage 20a.

  That is, the drive mechanism 52 can displace the throttle valve 51 in accordance with the temperature and pressure of the refrigerant on the outlet side of the suction-side evaporator 19 as in the so-called temperature type expansion valve. In other words, the drive mechanism 52 can displace the throttle valve 51 according to the degree of superheat of the refrigerant on the outlet side of the suction side evaporator 19.

  Therefore, in the drive mechanism 52, the throttle valve 51 is displaced so that the superheat degree SH1 of the refrigerant on the outlet side of the suction side evaporator 19 approaches a predetermined reference superheat degree KSH1 (specifically, 0 ° C.). In other words, the suction side pressure reducing device 15 changes the throttle opening so that the superheat degree SH1 of the refrigerant on the outlet side of the suction side evaporator 19 approaches the reference superheat degree KSH1. The reference superheat degree KSH1 can be adjusted by changing the load of the coil spring 52e.

  The bypass passage 16 is formed by a part of the first passage 16a formed in the body portion 21 and the second passage 16b. The first passage 16a is formed so as to connect the inlet side of the suction side pressure reducing device 15 (specifically, the inlet side of the throttle passage 20a) and the temperature sensitive passage 20b. The first passage 16a is formed in a substantially cylindrical shape. The central axis of the first passage 16 a extends in parallel with the displacement direction of the throttle valve 51.

  The second passage 16b is formed so as to connect the first passage 16a and the outlet side of the suction side pressure reducing device 15 (specifically, the outlet side of the throttle passage 20a). The second passage 16b is formed in a substantially cylindrical shape. The 2nd channel | path 16b is extended in the direction perpendicular | vertical to the central axis of the 1st channel | path 16a from the site | part which forms the side surface of the 1st channel | path 16a in the body part 21. As shown in FIG.

  Inside the first passage 16a, a substantially cylindrical valve body 17a constituting the variable throttle device 17 is disposed. A communication passage that connects the first passage 16a and the second passage 16b is formed in the valve body portion 17a.

  The valve body 17a opens and closes the bypass passage 16 by displacing in the central axis direction of the first passage 16a and opening and closing the inlet portion of the second passage 16b. Further, the valve body portion 17a is displaced in the direction of the central axis of the first passage 16a, and the passage opening area of the variable passage device 17 as a whole is changed by changing the passage cross-sectional area of the inlet portion of the second passage 16b. Let

  The valve body portion 17a circulates through the inlet-side pressure receiving surface that receives the inlet-side pressure Pri, which is the pressure of the refrigerant flowing from the refrigerant inlet 21a (that is, the refrigerant on the inlet side of the suction-side decompression device 15), and the temperature sensing passage 20b. It has an outlet side pressure receiving surface that receives the outlet side pressure Peo which is the pressure of the refrigerant (that is, the refrigerant flowing out of the suction side evaporator 19). The area of the inlet side pressure receiving surface and the area of the lower stage pressure receiving surface are set to be approximately equal.

  Further, a seal member such as an O-ring is interposed in the gap between the inner circumferential surface of the first passage 16a and the outer circumferential surface of the valve body portion 17a, and the refrigerant does not leak from the gap between these members. Further, the valve body 17a receives a load on the side where the bypass passage 16 is opened from a coil spring 17b which is an elastic member.

  For this reason, the valve body 17a of this embodiment is displaced according to the load generated by the pressure difference ΔP (ΔP = Pri−Peo) obtained by subtracting the outlet side pressure Peo from the inlet side pressure Pri and the load received from the coil spring 17b. .

  More specifically, in the variable throttle device 17 of the present embodiment, when the pressure difference ΔP is larger than a predetermined reference pressure difference KΔP, as shown in FIG. 2, the coil spring 17b is pushed and contracted. The valve body portion 17a is displaced so that the bypass passage 16 is closed.

  When the pressure difference ΔP becomes equal to or less than the reference pressure difference KΔP, as shown in FIG. 3, the valve body portion 17a is connected to the first passage 16a and the second passage 16b by the load of the coil spring 17b. Displace to. Then, by slightly opening the inlet portion of the second passage 16b, a throttle state in which a pressure reducing action is exerted is achieved.

  Further, as the pressure difference ΔP is reduced, the throttle opening is increased. Then, as shown in FIG. 4, the valve body portion 17a is displaced until the passage cross-sectional area of the inlet portion of the second passage 16b is maximized, so that the bypass passage 16 is fully opened.

  In the present embodiment, the pressure difference ΔP at which the flow rate Ge1 of the refrigerant flowing out from the suction side pressure reducing device 15 becomes the reference flow rate KGe1 is set to the reference pressure difference KΔP. For this reason, the variable throttle device 17 opens the bypass passage 16 when the flow rate Ge1 of the refrigerant flowing out from the suction side pressure reducing device 15 is equal to or less than the reference flow rate KGe1. The reference pressure difference KΔP can be adjusted by changing the load of the coil spring 17b.

  As shown in FIG. 1, the refrigerant inlet side of the suction side evaporator 19 is connected to the evaporator side outlet 21 b of the flow rate adjusting valve 20. The suction-side evaporator 19 exchanges heat between the refrigerant that has flowed out of the evaporator-side outlet 21b of the flow rate adjustment valve 20 and the blown air that has passed through the outflow-side evaporator 18, and evaporates the refrigerant to exert a heat absorption effect. An endothermic heat exchanger that cools blown air.

  The refrigerant outlet of the suction side evaporator 19 is connected to the evaporator side inlet 21c side of the flow rate adjustment valve 20. As described above, the refrigerant suction port 14 c side of the ejector 14 is connected to the low pressure outlet 21 d of the flow rate adjusting valve 20. In other words, the refrigerant outlet of the suction side evaporator 19 is connected to the refrigerant suction port 14 c side of the ejector 14 via the temperature sensing passage 20 b of the flow rate adjusting valve 20.

  Further, the outflow side evaporator 18 and the suction side evaporator 19 of the present embodiment are integrally configured. Specifically, each of the outflow side evaporator 18 and the suction side evaporator 19 includes a plurality of tubes that circulate the refrigerant, and a collection or distribution of refrigerants that are arranged at 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.

  Then, the outflow side evaporator 18 and the suction side evaporator 19 are integrated by forming the collecting / distributing tank of the outflow side evaporator 18 and the suction side evaporator 19 with the same member. In the present embodiment, the outflow side evaporator 18 and the suction side evaporator 19 are connected in series with the blowing air flow so that the outflow side evaporator 18 is arranged upstream of the blowing air flow with respect to the suction side evaporator 19. Is arranged. 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. The air conditioning control device 40 (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 an air conditioning control program stored in the ROM. The operation of the various control target devices 11, 12a, 18a connected to is controlled.

  On the input side of the air-conditioning control device 40, an inside air temperature sensor that detects the vehicle interior temperature Tr, an outside air temperature sensor that detects the outside air temperature Tam, a solar radiation sensor that detects the amount of solar radiation As in the vehicle interior, and a blowout from the suction side evaporator 19 A group of sensors for air conditioning control such as an evaporator temperature sensor for detecting the blown air temperature (evaporator temperature) Tefin is 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 40, and operation signals from various operation switches provided on the operation panel are input to the air conditioning control device 40. 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 40 of the present embodiment is configured such that a control unit that controls the operation of various devices to be controlled connected to the output side is integrally configured. A configuration (hardware and software) for controlling the operation of the control target 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 unit.

  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 40 executes an air-conditioning control program stored in advance to control the operations of the various control target devices 11, 12a, and 18a.

  In this air conditioning control program, the target blowing temperature TAO of the blown air blown into the vehicle interior is calculated based on the detection signal of the air conditioning control sensor group and the operation signal from the operation panel. And based on the target blowing temperature TAO etc., the operating state of each control object apparatus is determined. For example, about the compressor 11, it determines so that a refrigerant | coolant discharge capability (in this embodiment, rotation speed) may be reduced with the raise of the target blowing temperature TAO.

  Here, the target blowing temperature TAO is a value having a correlation with the amount of heat that the ejector refrigeration cycle needs to generate in order to keep the passenger compartment at a desired temperature (in other words, the heat load of the ejector refrigeration cycle 10). . Therefore, when cooling the passenger compartment, reducing the refrigerant discharge capacity of the compressor 11 as the target blowing temperature TAO increases increases the refrigerant discharge capacity of the compressor 11 as the cooling heat load decreases. It means to lower.

  When the air conditioning control device 40 decreases the refrigerant discharge capacity of the compressor 11 as the cooling heat load decreases, the flow rate of the circulating refrigerant that circulates in the cycle decreases, and the refrigerant flowing out of the suction-side decompression device 15 decreases. The flow rate Ge1 also decreases. Further, when the refrigerant discharge capacity of the compressor 11 is lowered with a decrease in the cooling heat load, the inlet side pressure Pri is lowered and the pressure difference ΔP is also reduced.

  Therefore, in the present embodiment, an operation condition in which the cooling heat load is relatively high and the refrigerant flow rate Ge1 flowing out from the suction-side decompression device 15 is greater than the reference flow rate KGe1 is defined as normal operation. The normal operation is performed when the outside air temperature is relatively high, for example, in summer.

  Further, an operation condition in which the cooling heat load is relatively low and the flow rate Ge1 of the refrigerant flowing out from the suction-side decompression device 15 is equal to or lower than the reference flow rate KGe1 is defined as low load operation. The low load operation is executed, for example, when the outside air temperature is relatively low, such as in spring or autumn, or when anti-fogging of the vehicle window is performed at the low outside air temperature.

  When the air conditioning control device 40 operates the compressor 11, 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 branch part 13 flows into the nozzle part 14 a of the ejector 14.

  The refrigerant that has flowed into the nozzle portion 14a of the ejector 14 is decompressed in an isentropic manner at the nozzle portion 14a and is injected from the refrigerant injection port of the nozzle portion 14a. Then, the refrigerant that has flowed out of the suction-side evaporator 19 by the suction action of the injected refrigerant is sucked from the refrigerant suction port 14 c through the temperature sensing passage 20 b of the flow rate adjustment valve 20.

  The injection refrigerant injected from the refrigerant injection port of the nozzle portion 14a and the suction refrigerant sucked from the refrigerant suction port 14c flow into the diffuser portion 14d. In the diffuser portion 14d, the velocity energy of the refrigerant is converted into pressure energy by expanding the refrigerant passage area. Thereby, the pressure of the mixed refrigerant of the injection refrigerant and the suction refrigerant increases. The refrigerant whose pressure has been increased in the diffuser section 14d flows into the outflow side evaporator 18.

  The refrigerant flowing into the outflow side evaporator 18 absorbs heat from the blown air blown by the indoor blower 18a and evaporates. Thereby, the blowing air blown by the indoor 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 branch portion 13 flows into the refrigerant inlet 21 a of the flow rate adjustment valve 20. Here, during the normal operation, since the variable throttle device 17 closes the bypass passage 16, the total flow rate of the refrigerant flowing into the refrigerant inlet 21 a of the flow rate adjusting valve 20 is reduced by the suction side pressure reducing device 15 to adjust the flow rate. It flows out from the evaporator side outlet 21b of the valve 20.

  During low load operation, the variable throttle device 17 opens the bypass passage 16, so that the refrigerant flowing into the refrigerant inlet 21 a of the flow rate adjustment valve 20 is decompressed by both the suction side decompression device 15 and the bypass passage 16. Then, it flows out from the evaporator side outlet 21b of the flow rate adjusting valve 20.

  At this time, in the suction-side decompression device 15, the superheat degree SH1 of the refrigerant on the outlet side of the suction-side evaporator 19 approaches the reference superheat degree KSH1 during normal operation and low load operation regardless of load fluctuations. As described above, the throttle opening is adjusted.

  The refrigerant that has flowed out of the evaporator-side outlet 21 b of the flow rate adjusting valve 20 flows into the suction-side evaporator 19. The refrigerant flowing into the suction side evaporator 19 absorbs heat from the blown air after passing 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 19 is sucked from the refrigerant suction port 14c.

  Therefore, according to the ejector-type refrigeration cycle 10 of the present embodiment, the outflow side evaporator 18 and the suction side evaporator 19 can be used in the vehicle interior during normal operation and low load operation regardless of load fluctuations. It is possible to cool the blown air sent to the air.

  Further, in the ejector refrigeration cycle 10 of the present embodiment, the refrigerant whose pressure has been increased by the diffuser portion 14 d of the ejector 14 is sucked into the compressor 11 via the outflow side evaporator 18. According to this, the consumption power of the compressor 11 is reduced and the coefficient of performance of the cycle is reduced compared to the normal refrigeration cycle apparatus in which the refrigerant evaporation pressure in the evaporator and the pressure of the suction refrigerant sucked into the compressor are substantially equal. (COP) can be improved.

  In the ejector refrigeration cycle 10 of the present embodiment, the variable throttle device 17 of the flow rate adjustment valve 20 closes the bypass passage 16 during normal operation. Therefore, during normal operation, the suction side decompression device 15 adjusts the throttle opening, so that the refrigerant on the outlet side of the suction side evaporator 19 can be a gas phase refrigerant having a superheat degree.

  According to this, it can suppress that the flow volume of the refrigerant | coolant suck | inhaled from the refrigerant | coolant suction port 14c of the ejector 14 increases unnecessarily, and suppresses that the pressure | voltage rise amount in the diffuser part 14d decreases. it can. That is, it can suppress that the COP of a cycle falls.

  However, since the flow rate of the refrigerant flowing into the suction side evaporator 19 decreases when the suction side pressure reducing device 15 adjusts the throttle opening degree during the low load operation as in the normal operation, the suction side evaporator 19 is reduced. The temperature distribution generated in the blown air cooled by the air will expand. That is, even if the throttle opening degree of the suction-side decompressor 15 is adjusted so that the superheat degree SH1 of the refrigerant on the outlet side of the suction-side evaporator 19 approaches the reference superheat degree KSH1, the suction side The flow rate of the refrigerant flowing into the evaporator 19 cannot be adjusted appropriately.

  On the other hand, in the ejector refrigeration cycle 10 of the present embodiment, the variable throttle device 17 of the flow rate adjustment valve 20 opens the bypass passage 16 during low load operation, so the suction side pressure reducing device 15 reduces the throttle opening. Even so, the refrigerant that has passed through the bypass passage 16 can surely flow out to the inlet side of the suction side evaporator 19. Therefore, it is possible to suppress a shortage of the flow rate of the refrigerant flowing into the suction side evaporator 19 during the low load operation.

  That is, according to the flow rate adjustment valve 20 of the present embodiment, when applied to the ejector refrigeration cycle 10, the flow rate of the refrigerant flowing into the suction-side evaporator 19 is appropriately adjusted according to cycle load fluctuations. be able to. In other words, according to the ejector refrigeration cycle 10 of the present embodiment, the flow rate adjustment valve 20 is provided, so that the flow rate of the refrigerant flowing into the suction-side evaporator 19 is appropriately adjusted according to the cycle load fluctuation. be able to.

  Further, the variable throttle device 17 of the flow rate adjustment valve 20 of the present embodiment increases the throttle opening as the pressure difference ΔP decreases. Therefore, the flow rate of the refrigerant flowing out to the inlet side of the suction side evaporator 19 through the bypass passage 16 can be increased with the decrease in the flow rate Ge1 of the refrigerant flowing out from the suction side decompression device 15. According to this, the flow rate of the refrigerant flowing into the suction side evaporator 19 can be more appropriately adjusted according to the cycle load fluctuation.

(Second Embodiment)
This embodiment demonstrates the example which changed the structure of the flow regulating valve 20 with respect to 1st Embodiment, as shown in FIG. FIG. 5 is a view in which the variable throttle device 17 of the present embodiment opens the bypass passage 16 in the fully open state, similarly to FIG. 4 described in the first embodiment. 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, in the flow rate adjustment valve 20 of the present embodiment, one end portion of the first passage 16a of the bypass passage 16 is the inlet side of the suction side pressure reducing device 15 (specifically, the inlet side of the throttle passage 20a). However, the other end of the first passage 16a does not communicate with the temperature sensing passage 20b.

  Furthermore, in the present embodiment, the inner peripheral surface of the first passage 16a and the valve body portion 17a so that the pressure Psp in the spring chamber 17c in which the coil spring 17b is accommodated is equal to the refrigerant pressure on the outlet side of the throttle passage 20a. A part of the sealing member interposed in the gap with the outer peripheral surface of is omitted. For this reason, the valve body part 17a of this embodiment is displaced according to the pressure difference which subtracted the pressure Psp in the spring chamber 17c from the inlet side pressure Pri and the load received from the coil spring 17b.

  Here, since the gap between the inner wall surface of the first passage 16a and the valve body portion 17a is relatively small, the pressure Psp in the spring chamber 17c is highly responsive in accordance with the change in the refrigerant pressure on the outlet side of the throttle passage 20a. It does not change and becomes a substantially constant value. For this reason, the valve body 17a of the present embodiment is displaced substantially according to the load generated by the inlet side pressure Pri and the load received from the coil spring 17b.

  More specifically, when the inlet side pressure Pri is larger than a predetermined reference pressure KPri, the valve body 17a is displaced toward the side where the coil spring 17b is compressed and the bypass passage 16 is fully closed. To do.

  When the inlet pressure Pri becomes equal to or lower than the reference pressure KPri, the valve body 17a is displaced to a position where the first passage 16a and the second passage 16b are communicated with each other by the load of the coil spring 17b. Set to the aperture state.

  Further, the throttle opening is increased as the inlet pressure Pri decreases. And as shown in FIG. 5, the valve body part 17a is displaced until the channel | path cross-sectional area of the inlet_port | entrance part of the 2nd channel | path 16b becomes the maximum, and the bypass channel | path 16 is made into a full open state.

  In the present embodiment, the inlet pressure Pri at which the flow rate Ge1 of the refrigerant flowing out from the suction side pressure reducing device 15 becomes the reference flow rate KGe1 is set to the reference pressure KPri. Thereby, the variable throttle device 17 opens the bypass passage 16 when the flow rate Ge1 of the refrigerant flowing out from the suction side pressure reducing device 15 is equal to or lower than the reference flow rate KGe1. The reference pressure KPri can be adjusted by changing the load of the coil spring 17b.

  Other configurations and operations of the flow rate adjusting valve 20 and the ejector refrigeration cycle 10 are the same as those in the first embodiment. That is, during normal operation of the ejector refrigeration cycle 10, the variable throttle device 17 of the flow rate adjustment valve 20 closes the bypass passage 16. Further, during the low load operation of the ejector refrigeration cycle 10, the variable throttle device 17 of the flow rate adjustment valve 20 opens the bypass passage 16.

  Therefore, according to the flow rate adjusting valve 20 of the present embodiment, when applied to the ejector refrigeration cycle 10, the flow rate adjusting valve 20 flows into the suction-side evaporator 19 according to the load fluctuation of the cycle, as in the first embodiment. The flow rate of the refrigerant can be adjusted appropriately. In other words, according to the ejector refrigeration cycle 10 of the present embodiment, the flow rate adjustment valve 20 is provided, so that the flow rate of the refrigerant flowing into the suction-side evaporator 19 is appropriately adjusted according to the cycle load fluctuation. be able to.

  In addition, the variable throttle device 17 of the flow rate adjusting valve 20 of the present embodiment increases the throttle opening as the inlet pressure Pri decreases. Therefore, the flow rate of the refrigerant flowing out to the inlet side of the suction side evaporator 19 through the bypass passage 16 can be increased with the decrease in the flow rate Ge1 of the refrigerant flowing out from the suction side decompression device 15. According to this, the flow rate of the refrigerant flowing into the suction side evaporator 19 can be more appropriately adjusted according to the cycle load fluctuation.

(Third embodiment)
In the present embodiment, an example in which the configuration of the flow rate adjustment valve 20 is changed as shown in FIG. 6 will be described. FIG. 6 is a view in which the variable throttle device 17 of the present embodiment opens the bypass passage 16 in the fully open state, similarly to FIG. 4 described in the first embodiment. In the variable throttle device 17 of the flow rate adjusting valve 20 of the present embodiment, the throttle opening can be increased with higher accuracy than the second embodiment as the inlet pressure Pri decreases.

  More specifically, in the flow regulating valve 20 of the present embodiment, a part of the first passage 16a of the bypass passage 16 is formed in a rotating body shape such as a hemispherical shape or a truncated cone shape similar to the throttle passage 20a. Yes. Furthermore, the same spherical body as the throttle valve 51 is adopted as the valve body portion 17d. The valve body portion 17d receives a load on the side of reducing the partial cross-sectional area of the first passage 16a from the coil spring 17b.

  In the flow regulating valve 20 of the present embodiment, the minimum passage sectional area (that is, the throttle opening) of the first passage 16a can be changed by displacing the valve body portion 17d. Further, the first passage 16a can be closed by bringing the valve body portion 17d into contact with the first passage 16a.

  In addition, the flow rate adjusting valve 20 of the present embodiment includes a drive mechanism 71 for the variable throttle device 17 as a drive unit that drives and displaces the valve body portion 17d. The basic configuration of the drive mechanism 71 for the variable aperture device 17 is the same as that of the drive mechanism 52.

  Therefore, the drive mechanism 71 has a temperature sensing part 72. The temperature sensing unit 72 includes a diaphragm 72b that is a deformable member that partitions the space in the temperature sensing unit 72 into an enclosed space 72c and an introduction space 72d. An inert gas (in this embodiment, nitrogen gas) is sealed in the sealed space 72c of the drive mechanism 71. The introduction space 72d of the drive mechanism 71 is fixed to the body portion 21 so as to communicate with the inlet side of the suction side pressure reducing device 15 (specifically, the throttle passage 20a).

  For this reason, the diaphragm 72b is deformed according to the pressure difference between the pressure of the refrigerant on the inlet side of the suction-side decompression device 15 and the pressure of the inert gas in the enclosed space 72c. Further, the drive mechanism 71 displaces the valve body portion 17d by transmitting the deformation of the diaphragm 72b to the valve body portion 17d via the operating rod 73.

  Here, the volume change due to the temperature of the inert gas is relatively small. For this reason, even if the temperature and the outside air temperature of the inlet side of the suction side decompression device 15 introduced into the introduction space 72d change, the pressure of the inert gas in the enclosed space 72c becomes substantially constant. Therefore, in the variable throttle device 17 of the present embodiment, the throttle opening can be increased with a decrease in the inlet-side pressure Pri with higher accuracy than in the second embodiment.

  Other configurations and operations of the flow rate adjusting valve 20 and the ejector refrigeration cycle 10 are the same as those in the second embodiment. Therefore, also in the flow regulating valve 20 and the ejector type refrigeration cycle 10 of the present embodiment, the same effect as in the second embodiment can be obtained.

(Fourth embodiment)
This embodiment demonstrates the example which changed the structure of the flow regulating valve 20 with respect to 1st Embodiment, as shown in FIG. Specifically, the variable throttle device 17 is abolished in the flow rate adjustment valve 20 of the present embodiment. For this reason, in the flow rate adjusting valve 20 of the present embodiment, the passage cross-sectional area of the bypass passage 16 and the like can appropriately adjust the flow rate of the refrigerant flowing into the suction side evaporator 19 according to the cycle load fluctuation. Is set to

  Specifically, in this embodiment, a reference medium temperature (this embodiment) determined in advance from the pressure of the refrigerant flowing through the temperature sensing passage 20b of the flow rate adjusting valve 20 and flowing out from the low-pressure outlet 21d (that is, outlet-side pressure Peo). In the embodiment, a value obtained by subtracting the saturation pressure of the temperature sensitive medium at 0 ° C.) is defined as the valve opening set pressure Y. A detailed method for measuring the valve opening set pressure Y will be described later.

  Further, the maximum value of the passage sectional area of the suction side pressure reducing device 15 is defined as the maximum throttle sectional area Aex, and the minimum value of the passage sectional area of the bypass passage 16 is defined as the minimum passage sectional area Apt. Furthermore, the ratio (Apt / Aex) of the maximum passage sectional area Apt to the maximum throttle sectional area Aex is defined as an area ratio X.

  Here, the maximum throttle cross-sectional area Aex can be determined based on the maximum circulation flow rate of the refrigerant circulating in the cycle. Therefore, in the flow regulating valve 20, the area ratio X can be changed mainly by changing the minimum passage sectional area Apt.

  Furthermore, as the area ratio X increases, the ratio of the flow rate of the refrigerant flowing into the suction side evaporator 19 via the bypass passage 16 tends to increase. For this reason, if the area ratio X is set to be large, the superheat degree SH1 of the refrigerant on the outlet side of the suction side evaporator 19 is changed to the reference superheat degree KSH1 even if the suction side pressure reducing device 15 changes the throttle opening during normal operation. There is a risk that it will be difficult to approach.

  On the other hand, as the area ratio X decreases, the ratio of the flow rate of the refrigerant flowing into the suction-side evaporator 19 via the bypass passage 16 decreases. For this reason, if the area ratio X is set to a small value, the flow rate of the refrigerant flowing into the suction side evaporator 19 may be insufficient when the suction side pressure reducing device 15 reduces the throttle opening degree during low load operation. is there.

  From this, it is necessary to adjust the area ratio X to a predetermined range in order to allow an appropriate flow rate of refrigerant to flow into the suction side evaporator 19 during normal operation and low load operation. However, it is difficult to accurately set an appropriate area ratio X according to the cooling capacity actually required for the ejector refrigeration cycle 10.

  Accordingly, the present inventors have noted that the valve opening set pressure Y of the flow rate adjusting valve 20 is related to the flow rate of the refrigerant flowing from the flow rate adjusting valve 20 to the suction side evaporator 19, and the valve opening set pressure is set. In relation to Y, we examined how to determine the area ratio X systematically.

  Here, the valve opening set pressure Y in the present embodiment is determined in advance from the “expansion valve outlet pressure” in the “Testing method for static superheat of expansion valves for automobile air conditioners” in the “Standard of the Japan Refrigeration and Air Conditioning Industry Association”. This corresponds to a pressure obtained by subtracting the saturation pressure of the temperature-sensitive medium in the enclosed space 52c at the reference medium temperature (0 ° C. in the present embodiment).

  More specifically, in this embodiment, as shown in FIG. 8, the pressure Py of the refrigerant flowing out from the low pressure outlet 21d of the flow rate adjustment valve 20 is measured, and the valve opening set pressure Y is determined using this value. ing. First, air having a test reference pressure KTPa (KTPa = 1.03 ± 0.05 MPa in this embodiment) is caused to flow into the refrigerant inlet 21 a of the flow rate adjusting valve 20.

The inlet side of the pressure vessel BT is connected to the evaporator side outlet 21b of the flow rate adjusting valve 20, and the evaporator side inlet 21c of the flow rate adjusting valve 20 is connected to the outlet side of the pressure vessel BT. The pressure vessel BT forms a buffer space corresponding to the suction side evaporator 19. In the present embodiment, a pressure vessel BT having an internal volume of the buffer space of 0.001 m ³ is employed.

  Then, the pressure Py of the air flowing out from the low pressure outlet 21d of the flow rate adjustment valve 20 is measured using the temperature of the temperature sensitive medium in the enclosed space 52c as the reference medium temperature. On the downstream side of the low-pressure outlet 21d, an orifice that causes a predetermined pressure loss is measured in order to measure the pressure Py. The pressure Py is substantially a pressure corresponding to the outlet-side pressure Peo that is the pressure of the refrigerant that has flowed out of the suction-side evaporator when the ejector refrigeration cycle 10 is operated. Further, the valve opening set pressure Y is determined by subtracting the saturation pressure of the temperature sensitive medium that is the reference medium temperature from the pressure Py.

  The valve opening set pressure Y is adjusted by changing the load of the coil spring 52e, similarly to the reference superheat degree KSH1.

  For this reason, when the reference superheat degree KSH1 is determined, as the valve opening set pressure Y is set to a high value, the throttle opening of the suction side pressure reducing device 15 increases. Therefore, the area ratio X may be decreased as the valve opening set pressure Y is set to a high value. On the other hand, as the valve opening set pressure Y is set to a low value, the throttle opening of the suction side pressure reducing device 15 decreases. Therefore, the area ratio X may be increased as the valve opening set pressure Y is set to a low value.

  As a result, as shown in FIG. 9, the present inventors set the area ratio X and the valve opening set pressure Y so as to satisfy the following formulas F1 and F2 during normal operation, so that an appropriate flow rate can be obtained. It was confirmed that the refrigerant could be supplied to the suction side evaporator 19.

−170X + 3 ≧ Y (F1)
Y ≧ −175X-60 (F2)
On the other hand, during low-load operation, it is confirmed that an appropriate flow rate of refrigerant can be supplied to the suction-side evaporator 19 by setting the area ratio X and the valve opening set pressure Y so as to satisfy the following formula F3. did.

Y ≧ −350X-9 (F3)
Then, the present inventors determine the area ratio X and the valve opening set pressure Y so as to satisfy the formulas F1 and F3 (so as to enter the shaded hatched region in FIG. 9) as a practically effective range. ing. In other words, the maximum throttle cross-sectional area Aex, the minimum passage cross-sectional area Apt, and the load of the coil spring 52e are adjusted so as to satisfy the expressions F1 and F3.

  That is, by satisfying Formula F1, the area ratio X and the valve opening set pressure are set so that the ratio of the flow rate of the refrigerant flowing into the suction-side evaporator 19 via the bypass passage 16 does not unnecessarily increase during normal operation. Y is determined. Furthermore, by satisfying Formula F3, the area ratio X and the valve opening set pressure Y are determined so that the flow rate of the refrigerant flowing into the suction-side evaporator 19 is not insufficient during low load operation.

  Other configurations of the flow rate adjusting valve 20 and the ejector refrigeration cycle 10 are the same as those in the first embodiment.

  Therefore, when the ejector refrigeration cycle 10 of this embodiment is operated, the refrigerant decompressed by the suction-side decompression device 15 regardless of load fluctuations, whether during normal operation or during low load operation. And the refrigerant that has passed through the bypass passage 16 can flow out from the evaporator-side outlet 21 b and flow into the suction-side evaporator 19.

  Here, as in the normal operation, the suction-side decompressor 15 increases the throttle opening degree under the operating condition in which the flow rate of the refrigerant flowing into the suction-side evaporator 19 is relatively large. For this reason, the ratio of the flow rate of the refrigerant flowing into the suction side evaporator 19 via the suction side pressure reducing device 15 in the flow rate of the refrigerant flowing into the suction side evaporator 19 increases. In other words, regarding the change in the flow rate of the refrigerant flowing into the suction-side evaporator 19, the degree of influence of the change in the throttle opening degree of the suction-side decompression device 15 increases.

  Further, in the present embodiment, the area ratio X and the valve opening set pressure Y are set so as to satisfy the above formula F1. Therefore, even if the bypass passage 16 is not closed, the suction side pressure reducing device 15 changes the throttle opening so that the superheat degree of the refrigerant on the outlet side of the suction side evaporator 19 approaches the reference superheat degree. The flow rate of the refrigerant flowing into the suction side evaporator 19 can be adjusted.

  On the other hand, the suction-side pressure reducing device 15 decreases the throttle opening when the operating condition is such that the flow rate of the refrigerant flowing into the suction-side evaporator 19 is relatively small, such as during low-load operation. For this reason, the ratio of the flow rate of the refrigerant that has passed through the bypass passage 16 in the flow rate of the refrigerant flowing into the suction side evaporator 19 increases. In other words, regarding the change in the flow rate of the refrigerant flowing into the suction-side evaporator 19 during the low load operation, the degree of influence of the change in the throttle opening degree of the suction-side decompression device 15 becomes small.

  Further, in the present embodiment, the area ratio X and the valve opening set pressure Y are set so as to satisfy the above formula F3. Therefore, at the time of low load operation, even if the suction side pressure reducing device 15 reduces the throttle opening, the refrigerant that has passed through the bypass passage 16 can surely flow into the suction side evaporator 19. Thereby, it can suppress that the flow volume of the refrigerant | coolant which flows in into the suction side evaporator 19 runs short.

  That is, according to the flow rate adjustment valve 20 of the present embodiment, when applied to the ejector refrigeration cycle 10, the flow rate of the refrigerant flowing into the suction-side evaporator 19 is appropriately adjusted according to cycle load fluctuations. be able to. In other words, according to the ejector refrigeration cycle 10 of the present embodiment, the flow rate adjustment valve 20 is provided, so that the flow rate of the refrigerant flowing into the suction-side evaporator 19 is appropriately adjusted according to the cycle load fluctuation. be able to.

  Further, according to studies by the present inventors, the above formulas F1 and F2 are differential pressures obtained by subtracting the area ratio X, which is a dimensionless number, and the saturation pressure determined by the physical properties of the refrigerant from the outlet side pressure Peo. Since the valve opening set pressure Y is used, it is also confirmed that the present invention is applicable to a wide range of refrigerants without being limited to R1234yf.

  That is, by setting the area ratio X and the valve opening set pressure Y so as to satisfy the above formulas F1 and F2, the ejector refrigeration cycle 10 that employs a wide variety of refrigerants is suitable for both normal operation and low load operation. It is possible to allow a refrigerant having a flow rate to flow into the suction side evaporator 19.

  In the above-described embodiment, similarly to the first embodiment, the refrigerant on the inlet side of the suction-side decompression device 15 is led to the outlet side of the suction-side decompression device 15 by bypassing the suction-side decompression device 15. The example in which the bypass passage 16 is arranged has been described, but the arrangement of the bypass passage 16 is not limited to this.

  That is, in the suction side decompression device 15, the part where the refrigerant is actually decompressed is in the vicinity of the minimum passage cross-sectional area of the throttle passage 20a. Therefore, as shown in the modification of FIG. 10, by connecting the upstream side of the minimum passage sectional area of the throttle passage 20a and the downstream side of the minimum passage sectional area of the throttle passage 20a, the bypass passage 16 is formed. It may be shortened.

(Fifth embodiment)
In the present embodiment, an example in which a nozzle side pressure reducing device 25 is added to the ejector refrigeration cycle 10 will be described as shown in the overall configuration diagram of FIG. 11 with respect to the first embodiment. The nozzle side pressure reducing device 25 is a variable throttle mechanism that reduces the pressure of the refrigerant branched by the branching portion 13 on the upstream side of the nozzle portion 14a. Further, the nozzle-side pressure reducing device 25 functions as a flow rate adjusting device that adjusts the flow rate of the refrigerant flowing into the nozzle portion 14a.

  The basic configuration of the nozzle side pressure reducing device 25 is a temperature type expansion valve similar to the suction side pressure reducing device 15 described in the first embodiment. In the nozzle side decompression device 25, the superheat degree SH of the refrigerant on the outlet side of the outflow side evaporator 18 (that is, the suction refrigerant sucked into the compressor 11) is a predetermined nozzle side reference superheat degree KSH (in this embodiment, The throttle opening is displaced so as to approach 1 ° C.

  Other configurations and operations of the ejector refrigeration cycle 10 are the same as those in the first embodiment. Therefore, also in the flow regulating valve 20 and the ejector type refrigeration cycle 10 of the present embodiment, the same effect as in the first embodiment can be obtained. Furthermore, since the ejector refrigeration cycle 10 of the present embodiment includes the nozzle-side decompression device 25, liquid compression of the compressor 11 can be reliably suppressed.

(Sixth embodiment)
In the present embodiment, an example will be described in which an intermediate pressure reducing device 26 is added to the ejector refrigeration cycle 10 as shown in the overall configuration diagram of FIG. 12 with respect to the first embodiment. The intermediate pressure depressurization device 26 is a variable throttle mechanism that depressurizes the refrigerant flowing out of the radiator 12 until it becomes an intermediate pressure refrigerant on the upstream side of the branch portion 13. Further, the intermediate pressure reducing device 26 functions as a flow rate adjusting device that adjusts the flow rate of the refrigerant flowing into the branch portion 13.

  The basic configuration of the intermediate pressure reducing device 26 is a temperature type expansion valve similar to the suction side pressure reducing device 15 described in the first embodiment. In the intermediate pressure reducing device 26, the superheat degree SH of the refrigerant on the outlet side of the outflow side evaporator 18 (that is, the suction refrigerant sucked into the compressor 11) is a predetermined nozzle side reference superheat degree KSH (in this embodiment, The throttle opening is displaced so as to approach 1 ° C.

  Other configurations and operations of the ejector refrigeration cycle 10 are the same as those in the first embodiment. Therefore, also in the flow regulating valve 20 and the ejector type refrigeration cycle 10 of the present embodiment, the same effect as in the first embodiment can be obtained. Furthermore, since the ejector refrigeration cycle 10 of the present embodiment includes the intermediate pressure reducing device 26, liquid compression of the compressor 11 can be reliably suppressed.

(Seventh embodiment)
In the present embodiment, an example in which the flow rate adjustment valve 20 described in the above-described embodiment is applied to the ejector refrigeration cycle 10a illustrated in the overall configuration diagram of FIG. 13 will be described.

  In the ejector refrigeration cycle 10a, the branching section 13 and the outflow side evaporator 18 are abolished with respect to the ejector refrigeration cycle 10 described in the first embodiment, and a gas-liquid separator 27 is provided. The gas-liquid separator 27 is a gas-liquid separator that stores the excess liquid-phase refrigerant separated by separating the gas-liquid of the refrigerant that has flowed out of the diffuser portion 14d.

  Further, in the ejector refrigeration cycle 10 a, the inlet side of the nozzle portion 14 a of the ejector 14 is connected to the outlet of the radiator 12. The gas-phase refrigerant outlet of the gas-liquid separator 27 is connected to the suction port side of the compressor 11, and the liquid-phase refrigerant outlet of the gas-liquid separator 27 is connected to the refrigerant inlet 21 a side of the flow rate adjusting valve 20. Yes.

  Other configurations of the ejector refrigeration cycle 10a are the same as those of the ejector refrigeration cycle 10 described in the first embodiment.

  Next, the operation of the ejector refrigeration cycle 10a in the above configuration will be described. When the air conditioning control device 40 operates the compressor 11, 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 refrigerant that has flowed out of the radiator 12 flows into the nozzle portion 14 a of the ejector 14.

  The refrigerant that has flowed into the nozzle portion 14a of the ejector 14 is decompressed in an isentropic manner at the nozzle portion 14a and is injected from the refrigerant injection port of the nozzle portion 14a. Then, the refrigerant that has flowed out of the suction-side evaporator 19 by the suction action of the injected refrigerant is sucked from the refrigerant suction port 14 c through the temperature sensing passage 20 b of the flow rate adjustment valve 20.

The injection refrigerant injected from the refrigerant injection port of the nozzle portion 14a and the suction refrigerant sucked from the refrigerant suction port 14c flow into the diffuser portion 14d. The refrigerant whose pressure has been increased in the diffuser section 14 d flows into the gas-liquid separator 27. The gas-phase refrigerant separated by the gas-liquid separator 27 is
It is sucked into the compressor 11 and compressed again. On the other hand, the liquid phase refrigerant separated by the gas-liquid separator 27 flows into the refrigerant inlet 21 a of the flow rate adjustment valve 20.

  At this time, as in the first embodiment, during normal operation, the refrigerant decompressed by the suction side decompression device 15 flows out from the evaporator side outlet 21b of the flow rate adjustment valve 20 and flows into the suction side evaporator 19. To do. Further, during low load operation, the refrigerant decompressed by the suction side decompression device 15 and the refrigerant that has passed through the bypass passage 16 flow out from the evaporator side outlet 21 b of the flow rate adjustment valve 20 and flow into the suction side evaporator 19. To do.

  The refrigerant flowing into the suction side evaporator 19 absorbs heat from the blown air blown by the indoor blower 18a and evaporates. Thereby, the blowing air blown by the indoor blower 18a is cooled. The refrigerant that has flowed out of the suction side evaporator 19 is sucked from the refrigerant suction port 14c.

  Therefore, according to the ejector refrigeration cycle 10a of the present embodiment, the blown air blown into the vehicle interior by the suction-side evaporator 19 during normal operation and low load operation regardless of load fluctuations. Can be cooled. And the effect similar to the ejector-type refrigerating cycle 10 demonstrated in 1st Embodiment can be acquired.

  That is, the flow rate adjusting valve 20 can appropriately adjust the flow rate of the refrigerant flowing into the suction side evaporator 19 even when applied to the ejector refrigeration cycle 10a. In other words, according to the ejector refrigeration cycle 10a of the present embodiment, the flow rate adjustment valve 20 is provided, so that the flow rate of the refrigerant flowing into the suction-side evaporator 19 is appropriately adjusted according to the cycle load fluctuation. be able to.

(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 above-described embodiment, the example in which the suction side pressure reducing device 15, the bypass passage 16, and the variable throttle device 17 are integrated as the flow rate adjusting valve 20 has been described, but the present invention is not limited to this. For example, the same effect can be obtained even if the ejector refrigeration cycle 10, 10a includes the suction side pressure reducing device 15, the bypass passage 16, and the variable throttle device 17 as separate components. Further, the branching unit 13, the ejector 14, and the like may be integrated with the flow rate adjusting valve 20.

  (2) In the second embodiment described above, the example in which the pressure Psp of the spring chamber 17c is the refrigerant pressure on the outlet side of the throttle passage 20a has been described, but the present invention is not limited to this. For example, the spring chamber 17c may be communicated with the outside air, and the pressure Psp of the spring chamber 17c may be set to the external pressure. The spring chamber 17c may be evacuated. In this case, as in the first embodiment, a seal member may be disposed in the gap between the inner wall surface of the first passage 16a and the valve body portion 17a.

  (3) In the above-described fourth embodiment, the example in which the bypass passage 16 is disposed as illustrated in FIG. 7 has been described, but the present invention is not limited to this. For example, the bypass passage 16 may be a relatively short distance extending from immediately before the throttle passage 20a to the downstream side of the throttle passage 20a. Further, the bypass passage 16 may be formed by cutting out a part of the inner peripheral surface of the portion of the body 21 where the throttle passage 20a is formed.

  (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 above-mentioned embodiment demonstrated the example which employ | adopted the thing of a three-way joint structure as the branch part 13, the branch part 13 is not limited to this. For example, as the branching section 13, a centrifugal type gas-liquid separator structure may be adopted as the branching section 13. In this case, the refrigerant having a relatively high dryness on the turning center side is caused to flow out to the nozzle portion 14a side of the ejector 14, and the refrigerant having a relatively low dryness on the outer peripheral side is caused to flow out to the refrigerant inlet 21a side of the flow rate adjusting valve 20. May be.

  In the above-described embodiment, the example in which the outflow side evaporator 18 and the suction side evaporator 19 are integrally configured has been described. However, the outflow side evaporator 18 and the suction side evaporator 19 are configured separately. Also good. And in the outflow side evaporator 18 and the suction side evaporator 19, different refrigerant target fluids may be cooled in different temperature zones.

  Moreover, although the above-mentioned embodiment demonstrated the example which employ | adopted R1234yf as a refrigerant | coolant, a refrigerant | coolant is not limited to this. For example, R134a, 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.

  (6) The means disclosed in each of the above embodiments may be appropriately combined within a practicable range. For example, the flow rate adjusting valve 20 described in the second to fourth embodiments may be applied to the ejector refrigeration cycles 10 and 10a described in the fifth to seventh embodiments.

DESCRIPTION OF SYMBOLS 10, 10a Ejector type refrigeration cycle 12 Radiator 14 Ejector 14a Nozzle part 14c Refrigerant suction port 15 Suction side decompression device (suction side decompression part)
16 Bypass passage 17 Variable throttle device (variable throttle mechanism)
19 Suction side evaporator 20 Flow control valve

Claims (9)

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 (14c) by the suction action of the jetted refrigerant jetted from the nozzle part (14a) for depressurizing the refrigerant flowing out of the radiator, and sucked from the jetted refrigerant and the refrigerant suction port An ejector (14) for increasing the pressure of the refrigerant mixed with the refrigerant;
A suction side decompression section (15) for decompressing the refrigerant;
A suction-side evaporator (19) for evaporating the refrigerant decompressed by the suction-side decompression unit and causing the refrigerant to flow out to the refrigerant suction port side;
A bypass passage (16) for guiding the refrigerant on the inlet side of the suction-side decompression unit to bypass the suction-side decompression unit to the inlet side of the suction-side evaporator;
A variable throttle mechanism (17) for adjusting the flow rate of the refrigerant flowing through the bypass passage,
The suction side decompression unit changes the throttle opening so that the superheat degree (SH1) of the refrigerant on the outlet side of the suction side evaporator approaches a predetermined reference superheat degree (KSH1),
The variable throttle mechanism has a function of opening and closing the bypass passage, and when the flow rate (Ge1) of the refrigerant flowing out from the suction-side decompression unit is equal to or lower than a predetermined reference flow rate (KGe1), An ejector-type refrigeration cycle that opens the bypass passage.   The variable throttle mechanism subtracts the outlet side pressure (Peo), which is the pressure of the refrigerant flowing out from the suction side evaporator, from the inlet side pressure (Pri), which is the pressure of the refrigerant on the inlet side of the suction side decompression unit. 2. The ejector refrigeration cycle according to claim 1, wherein the throttle opening is increased as the pressure difference (ΔP) is reduced.   2. The ejector type according to claim 1, wherein the variable throttle mechanism increases the throttle opening as the inlet side pressure (Pri), which is the pressure of the refrigerant on the inlet side of the suction side pressure reducing unit, decreases. Refrigeration cycle. 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 (14c) by the suction action of the jetted refrigerant jetted from the nozzle part (14a) for depressurizing the refrigerant flowing out of the radiator, and sucked from the jetted refrigerant and the refrigerant suction port An ejector (14) for increasing the pressure of the refrigerant mixed with the refrigerant;
A suction side decompression section (15) for decompressing the refrigerant;
A suction-side evaporator (19) for evaporating the refrigerant decompressed by the suction-side decompression unit and causing the refrigerant to flow out to the refrigerant suction port side;
A bypass passage (16) for guiding the refrigerant on the inlet side of the suction-side decompression unit to bypass the suction-side decompression unit to the inlet side of the suction-side evaporator,
The suction-side decompression unit is displaced according to the enclosed space (52c) in which a temperature-sensitive medium whose pressure changes with the temperature change of the refrigerant on the outlet side of the suction-side evaporator is enclosed, and the pressure of the temperature-sensitive medium A throttle valve (51) that changes the throttle opening so that the superheat degree (SH1) of the refrigerant on the outlet side of the suction side evaporator approaches a predetermined reference superheat degree (KSH1),
A value obtained by subtracting the saturation pressure of the temperature sensitive medium at a predetermined reference medium temperature from the outlet side pressure, which is the pressure of the refrigerant flowing out of the suction side evaporator, is defined as a valve opening set pressure (Y), and the suction side When the ratio (Apt / Aex) of the minimum passage sectional area (Apt) of the bypass passage to the maximum passage sectional area (Aex) of the decompression unit is defined as an area ratio X,
-170X + 3 ≧ Y
And,
Y ≧ −350X-9
Ejector type refrigeration cycle. A branch part (13) for branching the flow of the refrigerant flowing out of the radiator,
The inlet side of the nozzle part is connected to one outlet of the branch part (13),
The ejector-type refrigeration cycle according to any one of claims 1 to 4, wherein an inlet side of the suction side pressure reducing unit is connected to the other outlet of the branch part (13). The refrigerant is sucked from the refrigerant suction port (14c) by the suction action of the jetted refrigerant jetted from the nozzle part (14a) for depressurizing the refrigerant, and the mixed refrigerant of the jetted refrigerant and the sucked refrigerant sucked from the refrigerant suction port is A flow rate adjusting valve applied to an ejector refrigeration cycle (10, 10a) having an ejector (14) for boosting pressure, and a suction side evaporator (19) for evaporating a refrigerant to flow out to the refrigerant suction port side,
A suction side decompression section (15) for changing the throttle opening so that the superheat degree (SH1) of the refrigerant on the outlet side of the suction side evaporator approaches a predetermined reference superheat degree (KSH1);
A bypass passage (16) for guiding the refrigerant on the inlet side of the suction side decompression unit to the outlet side of the suction side decompression unit by bypassing the suction side decompression unit;
A variable throttle mechanism (17) for adjusting the flow rate of the refrigerant flowing through the bypass passage,
A refrigerant inlet side of the suction-side evaporator is connected to an evaporator-side outlet (21b) through which the refrigerant decompressed by the suction-side decompression unit flows out,
The variable throttle mechanism has a function of opening and closing the bypass passage, and a refrigerant flow rate (Ge1) flowing out from the suction-side decompression unit to a refrigerant inlet side of the suction-side evaporator is a predetermined reference flow rate (KGe1). ) A flow rate adjustment valve that opens the bypass passage when   The variable throttle mechanism subtracts an outlet side pressure (Peo), which is a pressure of the refrigerant flowing out from the suction side evaporator, from an inlet side pressure (Pri), which is a pressure of the refrigerant on the inlet side of the suction side decompression unit. The flow rate adjusting valve according to claim 6, wherein the throttle opening is increased as the pressure difference (ΔP) is reduced.   7. The flow rate adjustment according to claim 6, wherein the variable throttle mechanism increases the throttle opening as the inlet side pressure (Pri), which is the pressure of the refrigerant on the inlet side of the suction side pressure reducing unit, decreases. valve. The refrigerant is sucked from the refrigerant suction port (14c) by the suction action of the jetted refrigerant jetted from the nozzle part (14a) for depressurizing the refrigerant, and the mixed refrigerant of the jetted refrigerant and the sucked refrigerant sucked from the refrigerant suction port is A flow rate adjusting valve applied to an ejector refrigeration cycle (10, 10a) having an ejector (14) for boosting pressure, and a suction side evaporator (19) for evaporating a refrigerant to flow out to the refrigerant suction port side,
A suction side decompression section (15) for changing the throttle opening so that the superheat degree (SH1) of the refrigerant on the outlet side of the suction side evaporator approaches a predetermined reference superheat degree (KSH1);
A bypass passage (16) for guiding the refrigerant on the inlet side of the suction side decompression unit to the outlet side of the suction side decompression unit by bypassing the suction side decompression unit,
The suction-side decompression unit is displaced according to the enclosed space (52c) in which a temperature-sensitive medium whose pressure changes with the temperature change of the refrigerant on the outlet side of the suction-side evaporator is enclosed, and the pressure of the temperature-sensitive medium A throttle valve (51)
A refrigerant inlet side of the suction-side evaporator is connected to an evaporator-side outlet (21b) through which the refrigerant decompressed by the suction-side decompression unit flows out,
A value obtained by subtracting the saturation pressure of the temperature sensitive medium at a predetermined reference medium temperature from the outlet side pressure, which is the pressure of the refrigerant flowing out of the suction side evaporator, is defined as a valve opening set pressure (Y), and the suction side When the ratio (Apt / Aex) of the minimum passage sectional area (Apt) of the bypass passage to the maximum passage sectional area (Aex) of the decompression unit is defined as an area ratio X,
-170X + 3 ≧ Y
And,
Y ≧ −350X-9
The flow rate adjustment valve.

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