JP4725449B2 - Ejector refrigeration cycle - Google Patents

Description

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

  Conventionally, in Patent Document 1, the flow of the refrigerant is branched at a branching portion on the downstream side of the radiator that dissipates the refrigerant discharged from the compressor and on the upstream side of the nozzle portion of the ejector, and one of the branched refrigerants is directed to the nozzle portion side. An ejector-type refrigeration cycle is disclosed in which the other refrigerant flows into the refrigerant suction port side of the ejector.

  In the ejector-type refrigeration cycle of Patent Document 1, a first evaporator that evaporates the refrigerant that has flowed out of the ejector is disposed downstream of the diffuser portion of the ejector, and further, the refrigerant is placed between the branch portion and the refrigerant suction port of the ejector. A throttle mechanism for depressurization and a second evaporator that evaporates the refrigerant and flows out to the upstream side of the refrigerant suction port are arranged so that the refrigerant can exert an endothermic effect in both evaporators.

Further, the downstream side of the first evaporator is connected to the compressor suction side, and the refrigerant boosted by the diffuser portion of the ejector is sucked into the compressor, thereby reducing the compressor driving power and cycle efficiency (COP). We are trying to improve.
JP 2005-308380 A

  By the way, in this type of ejector, the loss of kinetic energy at the time of expansion is recovered by expanding the refrigerant isentropically in the nozzle portion, and the recovered energy (hereinafter referred to as recovered energy) is pressured in the diffuser portion. It is converted into energy.

Therefore, the ejector efficiency ηe indicating the energy conversion efficiency of the ejector is defined by the following formula F1.
ηe = (1 + Ge / Gnoz) × (ΔP / ρ) / Δi (F1)
Here, Ge is a flow rate of refrigerant sucked from the refrigerant suction port of the ejector, Gnoz is a flow rate of refrigerant passing through the nozzle portion of the ejector, ΔP is a pressure increase amount in the diffuser portion of the ejector, and ρ is a density of refrigerant sucked from the refrigerant suction port. , And Δi is the enthalpy difference between the nozzle part entrance and exit.

  As represented by the above formula F1, even if the size, shape, etc. of each part of the ejector is designed so that the ejector efficiency ηe becomes a desired value, enthalpy that is an index representing the recovered energy recovered at the nozzle part As long as the absolute amount of the difference Δi does not increase, the absolute amount of ΔP / ρ that is an index representing the pressure energy converted in the diffuser section cannot be increased.

  That is, at the predetermined ejector efficiency ηe, the absolute amount of the pressure increase ΔP cannot be increased unless the absolute amount of the enthalpy difference Δi is increased, and therefore the cycle efficiency (COP) improvement effect due to the increase of the compressor suction refrigerant pressure. Can not be expanded.

  An object of the present invention is to increase the amount of boosted pressure in the diffuser portion of the ejector by increasing the amount of recovered energy in the nozzle portion of the ejector.

In order to achieve the above object, in the present invention, a compressor (11) that compresses and discharges a refrigerant, a radiator (13) that radiates high-temperature and high-pressure refrigerant discharged from the compressor (11), and a radiator A gas-liquid separator (14) connected to the downstream side of (13), for separating the gas-liquid refrigerant flowing out of the radiator (13) and storing the liquid-phase refrigerant;
A branch part (Z) for branching the flow of the liquid-phase refrigerant in the gas-liquid separator (14) ;
Heating means (12, 19) for heating one liquid-phase refrigerant branched at the branch portion (Z) ;
The refrigerant heated by the heating means (12, 19) flows in , and the refrigerant is sucked by the nozzle portion (15a) for decompressing and expanding the inflowing refrigerant , and the high-speed refrigerant flow ejected from the nozzle portion (15a). An ejector (15) having a refrigerant suction port (15b);
Throttle means (17) for decompressing and expanding the other liquid-phase refrigerant branched at the branch portion (Z);
The evaporating the throttle means (17) downstream of the refrigerant, characterized by refrigerant cycle comprising an evaporator (18) flowing into the refrigerant suction port (15b) upstream.

According to this, the liquid refrigerant accumulated in the high-pressure gas-liquid separator (14) connected to the downstream side of the radiator (13) is heated by the heating means (12, 19), and the high pressure after this heating is Since the side refrigerant flows into the nozzle part (15a), the enthalpy of the inlet part side refrigerant of the nozzle part (15a) can be increased.

  Incidentally, when the enthalpy of the refrigerant on the inlet side of the nozzle portion (15a) increases, as shown in FIG. 2 described later, the amount of decrease in enthalpy when the refrigerant is isentropically expanded increases.

  That is, when the nozzle portion (15a) of the ejector (15) is isentropically expanded by the same pressure, the higher the enthalpy of the nozzle portion (15a) inlet-side refrigerant, the higher the enthalpy of the inlet portion refrigerant of the nozzle portion (15a). The difference from the enthalpy of the nozzle (15a) outlet side refrigerant, that is, the enthalpy difference (Δi) between the inlet and outlet of the nozzle (15a) increases.

  Therefore, if the ejector efficiency (ηe) is designed to have a desired value in the ejector-type refrigeration cycle having the above characteristics, the enthalpy difference (Δi), which is an index representing the recovered energy recovered by the nozzle portion (15a). The absolute amount of the pressure increase amount (ΔP) in the diffuser section (15d) can also be increased.

  As a result, the effect of improving the cycle efficiency (COP) due to the increase of the compressor suction refrigerant pressure can be further expanded with respect to the ejector refrigeration cycle of Patent Document 1.

Further, by increasing the enthalpy of the nozzle portion as the (15a) inlet side refrigerant, the nozzle portion (15a) vapor refrigerant fraction of the refrigerant on the inlet side (degree of dryness) increases. As the gas-phase refrigerant ratio (dryness) increases, the density of refrigerant passing through the nozzle portion (15a) decreases, so that the refrigerant at the same flow rate as the case where the nozzle portion (15a) inlet-side refrigerant is only liquid phase refrigerant. In order to reduce the pressure, the minimum passage area of the nozzle portion (15a) can be designed to be large.

  As a result, the processing of the nozzle portion (15a) is facilitated, and the processing cost of the nozzle 15a can be reduced.

In the ejector-type refrigeration cycle having the above characteristics, specifically, one liquid-phase refrigerant branched at the branch portion (Z) directly flows into the heating means (12, 19) and flows out from the heating means (12, 19). What is necessary is just to let the made refrigerant | coolant flow directly into a nozzle part (15a).
In the ejector refrigeration cycle having the above characteristics, the heating means (12) may use the amount of heat inside the cycle as a heat source. Specifically, the heating means may be an internal heat exchanger (12) that exchanges heat between the refrigerant flowing into the nozzle portion (15a) and the refrigerant discharged from the compressor (11). According to this, since the heating means (12) uses the amount of heat inside the cycle as a heat source, energy for heating the refrigerant flowing into the nozzle portion (15a) is not consumed.

  In the ejector refrigeration cycle having the above characteristics, the heating means (19) may use the amount of heat supplied from outside the cycle as a heat source. Specifically, the heating means may be an electric heater that generates heat when supplied with power.

  Further, in the case of an ejector refrigeration cycle applied to a vehicle that obtains driving power from an engine, the heating means is a heater core (19) that exchanges heat between the refrigerant flowing into the nozzle portion (15a) and the cooling water of the engine. May be. According to this, engine waste heat can be utilized effectively.

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

(First embodiment)
A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an overall configuration diagram of an example in which an ejector refrigeration cycle 10 of the present invention is applied to a vehicle air conditioner. First, in the ejector refrigeration cycle 10, the compressor 11 sucks in refrigerant, compresses and discharges it, and a driving force is transmitted from a vehicle engine (not shown) through an electromagnetic clutch 11a, a belt, and the like.

  As the compressor 11, a variable capacity compressor that can adjust the refrigerant discharge capacity by changing the discharge capacity, or a fixed capacity type that adjusts the refrigerant discharge capacity by changing the operating rate of the compressor operation by intermittently connecting the electromagnetic clutch 11a. Any of the compressors may be used. Further, if an electric compressor is used as the compressor 11, the refrigerant discharge capacity can be adjusted by adjusting the rotation speed of the electric motor.

  A compressor side refrigerant flow path 12 a of the heater 12 is connected to the discharge side of the compressor 11. The heater 12 is an internal heat exchanger that heats the refrigerant flowing from the receiver 14 to the nozzle portion 15a of the ejector 15 by exchanging heat between the refrigerant discharged from the compressor 11 and a liquid-phase refrigerant that has flowed out of the receiver 14 described later. is there. Therefore, in the present embodiment, the heater 12 constitutes a heating unit that uses the amount of heat in the cycle as a heat source.

  This heater 12 has a so-called double-tube heat exchanger configuration, specifically, inside the outer pipe that forms the compressor-side refrigerant flow path 12a through which the refrigerant discharged from the compressor 11 passes. It is the structure which has arrange | positioned the inner side pipe | tube which forms the receiver side refrigerant | coolant flow path 12b through which the receiver 14 exit side refrigerant | coolant passes. Of course, a configuration in which the outer surface of the compression side refrigerant passage 12a and the outer surface of the receiver side refrigerant passage 12b are joined by means such as welding or brazing may be employed.

  A radiator 13 is connected to the downstream side of the compressor-side refrigerant flow path 12 a of the heater 12. The radiator 13 cools the high-temperature refrigerant by exchanging heat between the high-temperature refrigerant on the outlet side of the heater 12 and the outside air (air outside the vehicle compartment) blown by a blower fan (not shown).

  In the ejector refrigeration cycle 10 of the present embodiment, a normal chlorofluorocarbon refrigerant is employed as the refrigerant, and a subcritical cycle in which the high-pressure side pressure does not exceed the critical pressure of the refrigerant is configured. Therefore, the radiator 13 functions as a condenser that condenses the refrigerant.

  A receiver 14, which is a gas-liquid separator that separates the gas-liquid refrigerant and stores the liquid-phase refrigerant, is connected to the downstream side of the radiator 13. The receiver 14 has a tank shape, and separates gas and liquid by the density difference between the gas-phase refrigerant and the liquid-phase refrigerant. Therefore, the liquid refrigerant accumulates on the lower side of the receiver 14 in the vertical direction.

  In addition, in this embodiment, although the heat radiator 13 and the receiver 14 are comprised as a different body, you may comprise the heat radiator 13 and the receiver 14 integrally. Further, as the heat radiator 13, a heat exchanger for condensation for condensing the refrigerant, a receiver 14 for introducing the refrigerant from the heat exchanger for condensation to separate the gas and liquid of the refrigerant, and a saturated liquid phase from the receiver 14 You may employ | adopt what is called a subcool type condenser which has a heat-exchange part for supercooling which supercools a refrigerant | coolant.

  A refrigerant pipe 14 a and a branch pipe 14 b are connected to the liquid phase refrigerant reservoir of the receiver 14. That is, the liquid-phase refrigerant separated by the receiver 14 is divided into a refrigerant flow that flows into the refrigerant pipe 14a and a refrigerant flow that flows into the branch pipe 14b. Therefore, in this embodiment, the branch part Z which branches the flow of a refrigerant | coolant to the liquid phase refrigerant | coolant storage part of the receiver 14 is comprised.

  The other end side of the refrigerant pipe 14a is connected to the receiver side refrigerant flow path 12b inlet side of the heater 12, and the nozzle portion 15a of the ejector 15 is connected to the receiver side refrigerant flow path 12b outlet side. The ejector 15 is a decompression unit that decompresses the refrigerant, and also a refrigerant circulation unit that circulates the refrigerant by suction of a refrigerant flow ejected at high speed.

  Further, the ejector 15 includes a nozzle portion 15a for reducing the passage area of the high-pressure refrigerant flowing from the receiver-side refrigerant flow passage 12b outlet side of the heater 12 to an isentropic decompression and expansion, and a nozzle portion 15a A refrigerant suction port 15b that is arranged so as to communicate with the refrigerant injection port and sucks the refrigerant that has flowed out of the evaporator 18 described later is configured.

  Furthermore, a mixing unit 15c that mixes the high-speed refrigerant flow ejected from the nozzle unit 15a and the refrigerant sucked from the refrigerant suction port 15b is provided on the downstream side of the refrigerant flow of the nozzle unit 15a and the refrigerant suction port 15b. A diffuser portion 15d forming a pressure increasing portion is provided on the downstream side of the refrigerant flow of the mixing portion 15c.

  The diffuser portion 15d is formed in a shape that gradually increases the refrigerant passage area, and acts to decelerate the refrigerant flow and increase the refrigerant pressure, that is, to convert the velocity energy of the refrigerant into pressure energy.

  The outlet side of the diffuser portion 15d of the ejector 15 is connected to the inlet side of the low-pressure side refrigerant passage 16b of the internal heat exchanger 16, and the suction side of the compressor 11 is connected to the outlet side of the low-pressure side refrigerant passage 16b. The internal heat exchanger 16 performs heat exchange between the radiator 13 outlet side refrigerant passing through the high pressure side refrigerant flow path 16a and the compressor 11 suction side refrigerant passing through the low pressure side refrigerant flow path 16b.

  As a specific configuration of the internal heat exchanger 16, a configuration similar to that of the heater 12 described above can be employed. In the present embodiment, a double-pipe heat exchanger configuration is adopted, and more specifically, the low-pressure side refrigerant flow path 16b is formed inside the outer pipe that forms the high-pressure side refrigerant flow path 16a. The inner tube is arranged.

  On the other hand, the other end of the branch pipe 14b connected to the liquid-phase refrigerant reservoir of the receiver 14 is connected to the high-pressure side refrigerant flow path 16a inlet side of the internal heat exchanger 16, and the high-pressure side refrigerant flow path 16a outlet. A diaphragm mechanism 17 is connected to the side. The throttle mechanism 17 is a throttle means that decompresses and expands the high-pressure refrigerant on the downstream side of the internal heat exchanger 16 and adjusts the refrigerant flow rate to the evaporator 18, and more specifically, a fixed throttle such as a capillary tube or an orifice. Can be configured.

  The inlet side of the evaporator 18 is connected to the downstream side of the throttle mechanism 17, and the outlet side of the evaporator 18 is connected to the refrigerant suction port 15 b. The evaporator 18 is a heat absorber that evaporates the refrigerant and exerts an endothermic action by exchanging heat between the low-pressure refrigerant passing through the inside and the blown air of a blower fan (not shown). Then, the blown air that has been absorbed by the evaporator 18 and cooled is blown out into the passenger compartment.

  Next, the operation of the present embodiment in the above configuration will be described. Note that the state of the refrigerant in the ejector refrigeration cycle of the present embodiment is schematically shown by a solid line in the Mollier diagram of FIG.

  First, when the compressor 11 is driven by a vehicle engine, the compressor 11 compresses and discharges the refrigerant. The state of the refrigerant at this time is point A in FIG. The high-temperature and high-pressure gas-phase refrigerant discharged from the compressor 11 dissipates heat by exchanging heat with the refrigerant downstream of the receiver 14 when passing through the compressor-side refrigerant flow path 12a of the heater 12 (point A in FIG. 2). → point B).

  The refrigerant that has flowed out of the compressor-side refrigerant flow path 12a of the heater 12 flows into the radiator 13, exchanges heat with the outside air blown by the blower fan, and further dissipates heat. Then, gas-liquid separation is performed at the receiver 14 (point C in the figure). The liquid-phase refrigerant that has flowed out of the receiver 14 to the refrigerant pipe 14a side is heated by exchanging heat with the refrigerant discharged from the compressor 11 when passing through the receiver-side refrigerant flow path 12b of the heater 12 (C in FIG. 2). Point → D).

  In addition, since the nozzle part 15a of the ejector 15 is connected to the downstream side of the receiver side refrigerant flow path 12b, the heater 12 exhibits an effect of increasing the enthalpy of the refrigerant on the inlet side of the nozzle part 15a as shown in FIG. is doing.

  The refrigerant flow that flows into the ejector 15 is decompressed and expanded by the nozzle portion 15a (point D → point E in FIG. 2). And the pressure energy of a refrigerant | coolant is converted into a velocity energy at the time of this decompression | expansion expansion, and a refrigerant | coolant is ejected at high speed from the refrigerant | coolant injection port of the nozzle part 15a. Due to the refrigerant suction action at this time, the refrigerant (vapor-phase refrigerant) after passing through the evaporator 18 is sucked from the refrigerant suction port 15b.

  In the mixing unit 15c, the refrigerant injected from the refrigerant injection port of the nozzle unit 15a and the suction refrigerant sucked from the refrigerant suction port 15b are mixed (point E → point F in FIG. 2) and flow into the diffuser unit 15d. To do. In the diffuser portion 15d, the refrigerant velocity (expansion) energy is converted into pressure energy due to expansion of the passage area, so that the refrigerant pressure increases (point F → point G in FIG. 2).

  The refrigerant that has flowed out of the diffuser portion 15d of the ejector 15 flows into the low-pressure side refrigerant flow path 16b of the internal heat exchanger 16, and passes through the high-pressure side refrigerant flow path 16a of the internal heat exchanger 16 and heat. Exchange and heat (point G → point H in FIG. 2). And the gaseous-phase refrigerant | coolant after passing the low voltage | pressure side refrigerant | coolant flow path 16b is suck | inhaled by the compressor 11, and is compressed again (H point-> A point of FIG. 2).

  On the other hand, the liquid-phase refrigerant that has flowed out from the receiver 14 to the branch pipe 14b side flows into the high-pressure side refrigerant channel 16a of the internal heat exchanger 16, and passes through the low-pressure side refrigerant channel 16a. Heat exchange is performed to dissipate heat (point C → point I in FIG. 2).

  Then, the liquid-phase refrigerant after passing through the high-pressure side refrigerant flow path 16a is decompressed by the throttle mechanism 17 to become a low-pressure refrigerant (point I → J in FIG. 2), and this low-pressure refrigerant flows into the evaporator 18. In the evaporator 18, the refrigerant absorbs heat from the air blown from the blower fan and evaporates (point J → point K in FIG. 2).

Then, the gas-phase refrigerant after passing through the evaporator 18 is sucked into the ejector 15 from the refrigerant suction port 15b , and this sucked refrigerant is mixed with the refrigerant injected from the refrigerant injection port of the nozzle portion 15a (point K in FIG. 2 → F point).

  As described above, in the present embodiment, since the liquid-phase refrigerant that has flowed from the receiver 14 to the branch pipe 14 b side can be supplied to the evaporator 18 via the throttle mechanism 17, the evaporator 18 can exhibit a cooling action. Further, the enthalpy of the refrigerant on the inlet side of the evaporator 18 is reduced by the heat exchange action in the internal heat exchanger 16 and the enthalpy difference between the evaporator inlet and outlet is expanded, so that the refrigerating capacity of the evaporator 18 can be improved. .

  Further, since the compressor 11 suction side is connected to the downstream side of the diffuser portion 15d of the ejector 15, the refrigerant sucked into the compressor 11 by the amount of pressure increase ΔP of the diffuser portion 15d with respect to the refrigerant evaporation pressure in the evaporator 18. The pressure can be increased. As a result, the compression work of the compressor 11 can be reduced and cycle efficiency (COP) can be improved.

  Here, the pressure increase amount ΔP of the diffuser unit 15d in the ejector refrigeration cycle of the present embodiment will be described in comparison with the cycle shown in FIG. Further, the state of the refrigerant in the comparative example cycle is schematically shown by a broken line in the Mollier diagram of FIG.

  First, the ejector refrigeration cycle shown in FIG. 3 (hereinafter referred to as a comparative example cycle) is separated from the cycle of the present embodiment by eliminating the heater 12 which is the main part of the present invention and by the receiver 14. In this cycle, the refrigerant is caused to flow directly into the nozzle portion 15a of the ejector 15 through the refrigerant pipe 14a. Other configurations are the same as the cycle of the present embodiment.

  Next, the operation of the comparative example cycle will be described. When the compressor 11 is driven by the vehicle engine, the compressor 11 compresses and discharges the refrigerant (point A ′ in FIG. 2). The high-temperature and high-pressure gas-phase refrigerant discharged from the compressor 11 flows into the radiator 13 and radiates heat by exchanging heat with the outside air blown by the blower fan. Then, gas-liquid separation is performed at the receiver 14 (point C in the figure).

  In the comparative example cycle, the amount of air blown to the radiator 12 by the blower fan is adjusted so that the state of the refrigerant on the outlet side of the radiator 12 is equivalent to the cycle of this embodiment.

  Further, in the comparative example cycle, since the heater 12 is eliminated, the refrigerant that has flowed from the receiver 14 to the refrigerant pipe 14a directly flows into the nozzle portion 15a of the ejector 15 and isentropically decompressed and expanded (FIG. 2 C point → E 'point). Further, the refrigerant is mixed with the refrigerant sucked from the refrigerant suction port 15b in the mixing unit 15c (point E ′ → point F ′ in FIG. 2).

  The mixed refrigerant flows into the diffuser section 15d and is pressurized (F ′ point → G ′ point in FIG. 2), heated in the internal heat exchanger 16 (G ′ point → H ′ point in FIG. 2), and further Then, it is sucked into the compressor 11 and compressed again (point H ′ → point A ′ in FIG. 2).

  On the other hand, the liquid-phase refrigerant that has flowed out from the receiver 14 to the branch pipe 14b side is sucked from the refrigerant suction port 15b via the internal heat exchanger 16 → throttle means 17 → evaporator 18 as in the cycle of the present embodiment, In the mixing portion 15c, the refrigerant is mixed with the jetting refrigerant in the nozzle portion 15a, and the pressure is increased in the diffuser portion 15d (point C → I point → J point → K point → F ′ point → G ′ point in FIG. 2).

  Here, the boost amount ΔP of the diffuser portion 15d in the cycle of the present embodiment is larger than the boost amount ΔP ′ of the diffuser portion 15d of the comparative example cycle, as shown in FIG. Therefore, according to the cycle of this embodiment, a high cycle efficiency (COP) improvement effect can be obtained with respect to the comparative example cycle.

  The reason is that in the cycle of this embodiment, the enthalpy of the refrigerant on the inlet side of the nozzle portion 15a of the ejector 15 can be increased with respect to the comparative example cycle by the action of the heater 12. When the enthalpy of the refrigerant on the inlet side of the nozzle portion 15a increases, the slope of the isentropic line becomes gentle as shown in FIG. Therefore, the amount of decrease in enthalpy when the refrigerant is isentropically expanded increases.

  That is, when the nozzle portion 15a of the ejector 15 is isentropically expanded by the same pressure, the higher the enthalpy of the nozzle portion 15a inlet-side refrigerant, the higher the enthalpy of the nozzle portion 15a inlet-side refrigerant and the enthalpy of the nozzle portion 15a outlet-side refrigerant. Δi (enthalpy difference between the inlet and outlet of the nozzle portion 15a) Δi increases.

  Therefore, as shown in FIG. 2, the absolute amount of the enthalpy difference Δi between the inlet / outlet of the nozzle portion 15a of the cycle of the present embodiment is larger than the absolute amount of the enthalpy difference Δi ′ of the comparative example cycle.

  Furthermore, when the absolute amount of the enthalpy difference Δi between the inlet and outlet of the nozzle portion 15 is increased, the size, shape, and the like of each portion of the ejector 15 are designed so that the ejector efficiency ηe becomes a desired value as shown in the above formula F1. In this case, the absolute amount of the boost amount ΔP in the diffuser portion 15d also increases.

  That is, in the present embodiment, the refrigerant flowing into the nozzle portion 15a is heated by the heater 12 to increase the enthalpy, so the enthalpy difference Δi between the inlet and outlet of the nozzle portion 15a is increased and the pressure increase amount of the diffuser portion 15d ΔP can be enlarged. As a result, a high cycle efficiency (COP) improvement effect can be obtained with respect to the comparative example cycle.

Furthermore, by increasing the enthalpy of the refrigerant on the inlet side of the nozzle portion 15a as described above, the gas phase refrigerant ratio (dryness) of the refrigerant on the inlet side of the nozzle portion 15a is increased . As the gas-phase refrigerant ratio of the nozzle portion 15a inlet-side refrigerant increases, the refrigerant density passing through the nozzle portion 15a decreases, so that the refrigerant having the same flow rate as the case where the nozzle portion 15a inlet-side refrigerant is only a liquid phase refrigerant is used. In order to reduce the pressure, the minimum passage area of the nozzle portion 15a can be designed large.

  As a result, the processing of the nozzle portion 15a is facilitated, and the processing cost of the nozzle 15a can be reduced. More specifically, as shown in FIG. 4, in the comparative example cycle, a pressure increase amount of about 0.17 MPa is obtained at an optimum passage diameter of 0.4 mm of the nozzle portion 15a. The path diameter can be increased to 0.6 mm, and a pressure increase of about 0.27 MPa can be obtained.

(Second Embodiment)
In 1st Embodiment, although the heating means is comprised by the heater 12 which heat-exchanges the compressor 11 discharge refrigerant | coolant and the receiver 14 effluent refrigerant | coolant, as shown in FIG. The heater core 19 is provided that heats the refrigerant flowing from the receiver 14 to the nozzle portion 15a of the ejector 15 by exchanging heat between the cooling water for cooling the vehicle engine and the refrigerant flowing out of the receiver 14.

  Therefore, in the present embodiment, the heater core 19 constitutes a heating unit that uses the amount of heat supplied from outside the cycle as a heat source. The heater core 19 can also be configured with a double tube heat exchanger configuration. Specifically, the inner tube forming the receiver side refrigerant flow path 19b through which the receiver 14 outlet side refrigerant passes is arranged inside the outer pipe forming the engine cooling water flow path 19a through which the engine cooling water passes. That's fine. Other configurations are the same as those of the first embodiment.

  Even when the cycle of the present embodiment is operated, the enthalpy of the refrigerant on the inlet side of the nozzle portion 15a of the ejector 15 can be increased by the action of the heater core 19, so that the cycle efficiency (COP) is high as in the first embodiment. An improvement effect can be obtained. Furthermore, since engine waste heat is used as a heat source for the heating means, the engine waste heat can be effectively utilized.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and can be variously modified as follows.

  (1) In each of the above-described embodiments, only the evaporator 18 that evaporates the refrigerant sucked into the refrigerant suction port 15b of the ejector 15 is provided, but further, the second is provided downstream of the diffuser portion 15d of the ejector 15. An evaporator may be provided. According to this, both the evaporator 18 and the second evaporator can exhibit a cooling action simultaneously.

  At this time, the refrigerant evaporation pressure of the evaporator 18 becomes the pressure immediately after the pressure reduction at the nozzle portion 14a, and the refrigerant evaporation pressure of the second evaporator becomes the pressure after the pressure increase by the diffuser portion 14d. The refrigerant evaporation pressure (refrigerant evaporation temperature) of the evaporator 18 can be made lower than the refrigerant evaporation pressure (refrigerant evaporation temperature) of the evaporator. Therefore, the space to be cooled can be cooled by the evaporators in two different temperature zones.

  Of course, these two evaporators may cool different cooling target spaces or the same cooling target space. Furthermore, when cooling the same space to be cooled, two evaporators may be integrated (unitized).

  (2) In the above-described embodiments, the cycle in which the internal heat exchanger 16 and the throttle means 17 are provided has been described. However, the throttle means 17 is abolished and the pressure is reduced in the high-pressure side refrigerant flow path 16a of the internal heat exchanger 16. You may make it exhibit a function. Specifically, the high-pressure side refrigerant flow path 16a may be configured by a capillary tube so that the heat is exchanged with the refrigerant passing through the low-pressure side refrigerant flow path 16b and simultaneously reduced.

  (3) In each above-mentioned embodiment, although branch part Z is arranged in the liquid phase refrigerant storage part of receiver 14, arrangement of branch part Z is not limited to this. For example, a configuration may be adopted in which one refrigerant pipe is connected to the liquid phase refrigerant reservoir of the receiver 14 and a three-way joint is provided in the refrigerant pipe to branch off.

  (4) In each of the above-described embodiments, in the above-described embodiment, the throttle mechanism 17 is configured by a fixed throttle. However, as the throttle mechanism 17, a variable throttle mechanism that can change the refrigerant passage area electrically and mechanically is used. It may be used.

  (5) In the second embodiment described above, the example in which the heater core 19 is employed as the heating unit using the amount of heat supplied from the outside of the cycle as the heat source has been described, but the heating unit is not limited thereto. For example, an electric heater that generates heat when supplied with power may be used. As this electric heater, a heating wire, a PTC heater, or the like can be adopted. Moreover, the structure which uses solar heat, geothermal heat, etc. as a heat source may be sufficient.

  (6) In each of the above-described embodiments, the refrigeration cycle for the vehicle has been described. However, the present invention is not limited to the vehicle and can be applied to the refrigeration cycle for stationary use as well.

  (7) In each of the above-described embodiments, an example in which a chlorofluorocarbon refrigerant is used as the refrigerant has been described. However, an HC refrigerant and carbon dioxide may be used.

  (8) In each of the above-described embodiments, the radiator 13 is an outdoor heat exchanger that exchanges heat between the refrigerant and the outside air, and the evaporator 18 is an indoor heat exchanger that is applied for cooling the vehicle interior. Conversely, the evaporator 18 is configured as an outdoor heat exchanger that absorbs heat from a heat source such as outside air, and the radiator 13 is configured as a heat pump cycle configured as an indoor heat exchanger that heats a heated fluid such as air or water. The invention may be applied.

It is a whole block diagram of the ejector-type refrigerating cycle of 1st Embodiment. It is a Mollier diagram which shows the state of the refrigerant | coolant of the cycle of 1st Embodiment. It is a whole block diagram of the comparative example cycle compared with 1st Embodiment. It is a graph explaining the difference of the pressure | voltage rise amount of the cycle of 1st Embodiment, and a comparative example cycle. It is a whole block diagram of the ejector type refrigerating cycle of 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Compressor, 12 ... Heater, 13 ... Radiator, 16, 30 ... Open / close valve,
15 ... Ejector, 15a ... Nozzle part, 15b ... Refrigerant suction port,
17 ... A throttle mechanism, 18 ... Evaporator, 19 ... Heater core.

Claims (7)

A compressor (11) for compressing and discharging the refrigerant;
A radiator (13) for radiating the high-temperature and high-pressure refrigerant discharged from the compressor (11);
A gas-liquid separator (14) connected to the downstream side of the radiator (13) and separating the gas-liquid refrigerant flowing out of the radiator (13) to store a liquid-phase refrigerant;
A branch part (Z) for branching the flow of the liquid-phase refrigerant in the gas-liquid separator (14) ;
Heating means (12, 19) for heating one liquid-phase refrigerant branched at the branch portion (Z) ;
The refrigerant heated by the heating means (12, 19) flows in , and the refrigerant is sucked by the nozzle portion (15a) for decompressing and expanding the inflowing refrigerant and the high-speed refrigerant flow ejected from the nozzle portion (15a). An ejector (15) having a refrigerant suction port (15b) for
Throttle means (17) for decompressing and expanding the other liquid-phase refrigerant branched at the branch portion (Z);
The throttle means (17) to evaporate the refrigerant on the downstream side, the refrigerant suction port (15b) evaporator flows to the upstream side (18) and the ejector type refrigeration cycle, characterized in that it comprises a. One liquid-phase refrigerant branched at the branch part (Z) directly flows into the heating means (12, 19), and the refrigerant flowing out of the heating means (12, 19) directly enters the nozzle part (15a). The ejector type refrigeration cycle according to claim 1, wherein the ejector type refrigeration cycle flows. The ejector refrigeration cycle according to claim 1 or 2 , wherein the heating means (12) uses the amount of heat inside the cycle as a heat source. The ejector according to claim 3 , wherein the heating means is an internal heat exchanger (12) for exchanging heat between the refrigerant flowing into the nozzle portion (15a) and the refrigerant discharged from the compressor (11). Refrigeration cycle. The ejector refrigeration cycle according to claim 1 or 2 , wherein the heating means (19) uses heat supplied from outside the cycle as a heat source. 6. The ejector refrigeration cycle according to claim 5 , wherein the heating means is an electric heater that generates heat when supplied with power. The ejector refrigeration cycle according to claim 5 , which is applied to a vehicle that obtains traveling power from an engine.
The ejector refrigeration cycle, wherein the heating means is a heater core (19) for exchanging heat between the refrigerant flowing into the nozzle portion (15a) and the cooling water of the engine.

Images