JP6183223B2 - Heat pump cycle - Google Patents

Description

  The present invention relates to a heat pump cycle.

  Patent Documents 1 and 2 describe an integrated valve that can simplify the cycle configuration of a heat pump cycle. In both integrated valves, a fixed throttle for depressurizing the liquid-phase refrigerant and a valve body for opening and closing the gas-phase refrigerant passage and the liquid-phase refrigerant passage are housed in a metal body in which a gas-liquid separation space is formed. It is a thing.

  In such an integrated valve, since the temperature difference between the refrigerant after passing through the fixed throttle and the refrigerant in the gas-liquid separation space is large, the refrigerant after passing through the fixed throttle and the refrigerant in the gas-liquid separation space There arises a problem that the heat exchange occurs. Therefore, as a countermeasure against this problem, Patent Documents 1 and 2 propose that the fixed restrictor and the fixed restrictor outlet flow path portion are made of resin parts having a higher thermal resistance than metal and the resin parts are inserted into the body. It is described in.

JP 2013-92355 A JP 2013-92354 A

  However, in the above-described conventional technology, as described below, the heat exchange through the body is not sufficiently suppressed, and the heating performance inherent in the cycle when the heat pump cycle functions as a gas injection cycle cannot be sufficiently exhibited. I understood it.

  Specifically, in the above-described conventional technology, a gap is generated between the resin component and the body. Therefore, by providing an O-ring on the outer periphery of the resin component, the gap between the resin component and the body is moved to the outside of the body. Prevents refrigerant leakage. However, the O-ring blocks the refrigerant that has entered the gap between the resin component and the body, and does not prevent the refrigerant from entering the resin component and the body.

  For this reason, in the above-described prior art, when the state of the integrated valve is set to a state where the refrigerant passes through the fixed throttle, the low-temperature refrigerant after passing through the fixed throttle is inserted into the gap between the resin component and the body from the refrigerant outlet side of the integrated valve. It flows in. As a result, the low-temperature refrigerant after passing through the fixed throttle directly touches the inner surface of the body, whereby the entire body is cooled and the high-temperature refrigerant inside the body is cooled. In other words, the cold refrigerant after passing through the fixed throttle and the high-temperature refrigerant inside the body exchange heat through the body.

  If the refrigerant before and after passing through the fixed restrictor exchanges heat, the dryness of the refrigerant before passing through the fixed restrictor decreases, and the dryness of the refrigerant after passing through the fixed restrictor increases. For this reason, the specific entropy of the inlet refrigerant of the evaporator increases, the specific entropy difference between the inlet refrigerant and the outlet refrigerant of the evaporator decreases, and the heat absorption amount of the evaporator decreases. In addition, when the intermediate-pressure gas-phase refrigerant sucked into the compressor is cooled by exchanging heat, the dryness of the refrigerant decreases, the gas-phase refrigerant sucked into the compressor decreases, and the compressor discharge Refrigerant amount decreases. For this reason, compared with the heating capability which a cycle originally has, heating capability will fall.

  An object of this invention is to provide the heat pump cycle which can suppress the fall of heating capability rather than a prior art in view of the said point.

In order to achieve the above object, the invention according to claim 1 or 2 ,
An intermediate pressure port (11b) that compresses the low-pressure refrigerant sucked from the suction port (11a) and discharges the high-pressure refrigerant from the discharge port (11c), and flows the intermediate-pressure refrigerant in the cycle into the refrigerant in the compression process. A compressor (11) having
A heat radiator (12) that heat-exchanges the high-pressure refrigerant by heat-exchanging the high-pressure refrigerant discharged from the discharge port and the heat exchange target fluid,
Decompression means (13) for decompressing the high-pressure refrigerant flowing out of the radiator until it becomes an intermediate-pressure refrigerant;
An integrated valve (14) having a function of separating the gas-liquid of the intermediate pressure refrigerant depressurized at least by the depressurizing means;
A fixed throttle (17) for reducing the intermediate-pressure liquid-phase refrigerant flowing out of the integrated valve to a low-pressure refrigerant;
An evaporator (20) for evaporating the low-pressure refrigerant flowing out from the fixed throttle and flowing out to the suction port side,
The integrated valve includes a refrigerant inlet (141a) through which the intermediate pressure refrigerant decompressed by the decompression means flows, a gas-liquid separation space (141b) that separates the gas and liquid of the refrigerant flowing in from the refrigerant inlet, and a gas-liquid separation space. The first refrigerant outlet (142a) for flowing the separated gas-phase refrigerant to the intermediate pressure port side and the second refrigerant outlet (141e) for flowing the liquid-phase refrigerant separated in the gas-liquid separation space to the evaporator side ) And a third refrigerant outlet (141i) formed body (140),
Inside the body, a gas phase refrigerant passage (142b) from the gas-liquid separation space to the first refrigerant outlet is opened and closed, and a liquid phase refrigerant passage (141d1) from the gas-liquid separation space to the second refrigerant outlet is provided. The valve body (15, 18, 29) which opens and closes is accommodated,
The body is a liquid that causes the liquid-phase refrigerant separated in the gas-liquid separation space to flow out from the third refrigerant outlet when the valve body closes the liquid-phase refrigerant passage from the gas-liquid separation space to the second refrigerant outlet. Phase refrigerant passage (141d2) is formed,
In addition, piping parts (61, 62, 63, 71) that are arranged outside the body and are formed separately from the body and constitute a refrigerant passage from the third refrigerant outlet to the refrigerant inlet of the evaporator. Prepared,
The piping parts have joints (51, 61, 71) directly connected to the second refrigerant outlet and the third refrigerant outlet of the body, and pipes (52, 62, 72) directly connected to the joints. ,
The fixed throttle is provided in the internal passages (61b, 71b) of the joints (61, 71) through which the refrigerant flowing out of the third refrigerant outlet flows .
Further, the invention according to claim 1 is characterized in that the joint has a recess (61c, 71f) that forms a gap between the joint and the outer surface of the body at a portion facing the outer surface of the body. The invention according to claim 2 is characterized in that members (61d, 71g) having higher thermal resistance than the body and the joint are arranged between the outer surface of the body and the joint.

In the first and second aspects of the invention, since the fixed throttle is provided in the piping parts arranged outside the body of the integrated valve, the refrigerant after passing through the fixed throttle is kept away from the body and does not directly contact the body. Can be. Further, in the first and second aspects of the invention, since the piping parts constituting the fixed throttle outlet channel are separate from the body, the components of the fixed throttle outlet channel are integral with the body, that is, with the same material. The thermal resistance between this component and the body is higher than in the case where they are configured continuously. For this reason, the amount of heat exchange between the refrigerant after passing through the fixed throttle and the refrigerant inside the body via the piping parts and the body can be greatly reduced.

Therefore, according to the first and second aspects of the present invention, the amount of heat exchange between the refrigerant after passing through the fixed throttle and the refrigerant inside the body can be reduced as compared with the prior art, and the heating capacity is reduced as compared with the prior art. Can be suppressed.

  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 which shows the refrigerant circuit at the time of the air_conditionaing | cooling operation mode and dehumidification heating operation mode of the heat pump cycle in 1st Embodiment. It is a whole block diagram which shows the refrigerant circuit at the time of the 1st heating mode of the heat pump cycle in 1st Embodiment. It is a whole block diagram which shows the refrigerant circuit at the time of the 2nd heating mode of the heat pump cycle in 1st Embodiment. It is an up-down direction sectional view in the non-energized state of the integrated valve in a 1st embodiment. It is an up-down direction sectional view in the energized state of the integrated valve in a 1st embodiment. It is VI-VI sectional drawing of FIG. It is VII-VII sectional drawing of FIG. It is an enlarged view of the joint by the side of the integrated valve in FIG. It is an up-down direction sectional view in the non-energized state of the integrated valve in a 2nd embodiment. It is an up-down direction sectional view in the non-energized state of the integrated valve in a 3rd embodiment. It is a whole block diagram which shows the refrigerant circuit at the time of the 1st heating mode of the heat pump cycle in 4th Embodiment. It is an up-down direction sectional view in the non-energized state of the integrated valve in a 4th embodiment. FIG. 13 is an enlarged view of the joint on the integrated valve side in FIG. 12. It is an enlarged view of the joint by the side of the integrated valve in 5th Embodiment. It is an enlarged view of the joint by the side of the integrated valve in 6th Embodiment. It is an enlarged view of the joint by the side of the integrated valve in 7th Embodiment. It is an enlarged view of the joint by the side of the integrated valve in 8th Embodiment. It is sectional drawing of the up-down direction of the integrated valve in 9th Embodiment. It is sectional drawing of the up-down direction of the integrated valve in 9th Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other will be described with the same reference numerals.

(First embodiment)
1st Embodiment of this invention is described using FIGS. In this embodiment, the heat pump cycle (vapor compression refrigeration cycle) 10 of the present invention is applied to a vehicle air conditioner 1 for an electric vehicle that obtains a driving force for vehicle traveling from a traveling electric motor. The heat pump cycle 10 functions to cool or heat the blown air that is blown into the vehicle interior that is the air-conditioning target space in the vehicle air conditioner 1. Therefore, the heat exchange target fluid of this embodiment is blown air.

  Further, as shown in the overall configuration diagram of FIG. 1, the heat pump cycle 10 includes a cooling operation mode (cooling operation mode for cooling the blown air) for cooling the vehicle interior or a dehumidifying heating operation mode for heating while dehumidifying the vehicle interior ( The refrigerant circuit in the dehumidifying operation mode) and the refrigerant circuit in the heating operation mode for heating the vehicle interior (the heating operation mode for heating the blown air) can be switched as shown in the overall configuration diagrams of FIGS. Has been.

  More specifically, in the heat pump cycle 10, as will be described later, as a heating operation mode, the first heating mode (FIG. 2) that is executed when the outside air temperature is extremely low (for example, 0 ° C. or less), The second heating mode (FIG. 3) in which heating is performed can be switched. In FIGS. 1 to 3, the flow of the refrigerant in each operation mode is indicated by solid arrows.

  The heat pump cycle 10 employs an HFC-based refrigerant (specifically, R134a) as the refrigerant, and constitutes a vapor compression subcritical refrigeration cycle in which the high-pressure side refrigerant pressure Pd does not exceed the refrigerant critical pressure. doing. Of course, you may employ | adopt HFO type refrigerant | coolants (for example, R1234yf).

  Among the components of the heat pump cycle 10, the compressor 11 is disposed in the hood of the vehicle, and sucks, compresses and discharges the refrigerant in the heat pump cycle 10. The compressor 11 accommodates two compression mechanisms, a low-stage compression mechanism and a high-stage compression mechanism, and an electric motor that rotationally drives both compression mechanisms in a housing that forms an outer shell thereof. Is a two-stage booster type electric compressor configured as described above.

  A suction port 11a for sucking low-pressure refrigerant from the outside of the housing into the low-stage compression mechanism, and an intermediate-pressure refrigerant in the cycle from the outside of the housing to the inside of the housing flow into the housing of the compressor 11 from low pressure to high pressure. An intermediate pressure port 11b that joins the refrigerant in the compression process and a discharge port 11c that discharges the high-pressure refrigerant discharged from the high-stage compression mechanism to the outside of the housing are provided.

  More specifically, the intermediate pressure port 11b is connected to the refrigerant discharge port side of the low-stage compression mechanism (that is, the refrigerant suction port side of the high-stage compression mechanism). Various types such as a scroll type compression mechanism, a vane type compression mechanism, and a rolling piston type compression mechanism can be adopted as the low stage side compression mechanism and the high stage side compressor.

  The operation (rotation speed) of the electric motor is controlled by a control signal output from the air conditioning control device 40 described later, and either an AC motor or a DC motor may be adopted. And the refrigerant | coolant discharge capability of the compressor 11 is changed by this rotation speed control. Therefore, in this embodiment, the electric motor constitutes the discharge capacity changing means of the compressor 11.

  In addition, in this embodiment, although the compressor 11 which accommodated two compression mechanisms in one housing is employ | adopted, the format of a compressor is not limited to this. That is, if the intermediate pressure refrigerant can be introduced from the intermediate pressure port 11b and merged with the refrigerant in the compression process from low pressure to high pressure, one fixed capacity type compression mechanism and the compression mechanism are provided inside the housing. An electric compressor configured to accommodate an electric motor that rotationally drives the motor may be used.

  Further, two compressors are connected in series, and the suction port of the low-stage compressor disposed on the low-stage side serves as the suction port 11a, and the discharge port of the high-stage compressor disposed on the high-stage side serves as the suction port 11a. An intermediate pressure port 11b is provided at a connecting portion that connects the discharge port of the low-stage side compressor and the suction port of the high-stage side compressor as the discharge port 11c, and connects the low-stage side compressor and the high-stage side compressor. You may comprise one two-stage pressure | voltage rise type compressor by both.

  The refrigerant inlet side of the indoor condenser 12 is connected to the discharge port 11 c of the compressor 11. The indoor condenser 12 is arrange | positioned in the air-conditioning case 31 of the indoor air-conditioning unit 30 of the vehicle air conditioner 1 mentioned later. The indoor condenser 12 is a radiator that causes heat exchange between the high-temperature and high-pressure refrigerant discharged from the compressor 11 and blown air that has passed through an indoor evaporator 23 described later, and dissipates the high-temperature and high-pressure refrigerant. A heat exchanger for heating.

  Connected to the refrigerant outlet side of the indoor condenser 12 is the inlet side of the high-stage expansion valve 13 as pressure reducing means (first pressure reducing means) for reducing the pressure of the high-pressure refrigerant flowing out of the indoor condenser 12 until it becomes intermediate pressure refrigerant. ing. The high-stage expansion valve 13 is an electric type that includes a valve body that can change the throttle opening degree and an electric actuator that includes a stepping motor that changes the throttle opening degree of the valve body. This is a variable aperture mechanism. The operation of the high stage side expansion valve 13 is controlled by a control signal output from the air conditioning control device 40. The high stage side expansion valve 13 can be made not to exhibit the refrigerant decompression action by fully opening the throttle opening. A refrigerant inlet 141 a of the integrated valve 14 is connected to the outlet side of the high stage side expansion valve 13.

  The integrated valve 14 opens and closes a gas-liquid separation space 141b that separates the gas-liquid refrigerant flowing out from the high-stage side expansion valve 13, and a gas-phase refrigerant passage through which the gas-phase refrigerant separated in the gas-liquid separation space 141b flows. The gas-phase refrigerant-side valve body 18, the liquid-phase refrigerant-side valve body 15 that opens and closes the liquid-phase refrigerant passage through which the liquid-phase refrigerant separated in the gas-liquid separation space 141b flows, and the like are integrally configured.

  In other words, this integrated valve 14 is an integral part of the components required to make the heat pump cycle 10 function as a gas injection cycle, and further switches the refrigerant circuit of the refrigerant circulating in the cycle. It functions as a refrigerant circuit switching means.

  The detailed configuration of the integrated valve 14 will be described with reference to FIGS. In addition, the up and down arrows in FIGS. 4 and 5 indicate the up and down directions in a state where the integrated valve 14 is mounted on the vehicle air conditioner 1.

  As shown in FIGS. 4 and 5, the integrated valve 14 has a body 140 that forms an outer shell thereof and that accommodates the gas phase refrigerant side valve body 18, the liquid phase refrigerant side valve body 15, and the like. . The body 140 includes a lower body 141 disposed on the lower side and an upper body 142 attached and fixed on the upper side of the lower body 141.

  First, the lower body 141 is formed of a substantially bottomed rectangular cylindrical metal block whose axial direction extends in the vertical direction, and a gas-liquid separation space 141b is formed therein. The gas-liquid separation space 141b is formed in a substantially cylindrical shape whose axial direction extends in the vertical direction.

  In addition, the lower body 141 has a refrigerant inlet 141a through which the refrigerant flowing out from the high-stage expansion valve 13 flows into the gas-liquid separation space 141b on the outer peripheral side wall surface. A refrigerant introduction passage 141h that guides the refrigerant from the refrigerant inlet 141a to the gas-liquid separation space 141b communicates with the gas-liquid separation space 141b via a refrigerant introduction hole 141g formed in a radial wall surface of the gas-liquid separation space 141b. ing. As shown in FIG. 7, the refrigerant introduction passage 141h of the present embodiment has a circular cross-section of the gas-liquid separation space 141b when viewed from the axial direction of the gas-liquid separation space 141b (vertical direction in the present embodiment). It extends in the tangential direction of the inner peripheral side wall surface.

  Therefore, the refrigerant that has flowed into the gas-liquid separation space 141b from the refrigerant inlet 141a flows so as to swirl along the inner circumferential side wall surface of the gas-liquid separation space 141b having a circular cross section. Then, the gas-liquid refrigerant flowing into the gas-liquid separation space 141b is separated by the action of the centrifugal force generated by the swirling flow, and the separated liquid-phase refrigerant falls to the lower side of the gas-liquid separation space 141b by the action of gravity. To do. In other words, the gas-liquid separation space 141b of the present embodiment constitutes a centrifugal-type gas-liquid separation means.

  Here, as shown in FIG. 6, the refrigerant introduction hole 141g of the present embodiment is formed of a long hole extending in the axial direction of the gas-liquid separation space 141b. For this reason, when the refrigerant introduced into the gas-liquid separation space 141b swirls in the gas-liquid separation space 141b, the main flow does not diffuse radially inward of the gas-liquid separation space 141b. It turns along the radially outer wall surface. Thus, the centrifugal force is effectively applied to the refrigerant that has flowed into the gas-liquid separation space 141b, thereby improving the gas-liquid separation efficiency inside the integrated valve 14.

  Furthermore, the refrigerant introduction hole 141g of the present embodiment opens at a position closer to the other end side (upper end side) in the longitudinal direction than one end portion (lower end portion) in the longitudinal direction of a separated vapor phase refrigerant outflow pipe portion 142c described later. ing. Thereby, the run-up section of the refrigerant swirling in the gas-liquid separation space 141b is sufficiently ensured, and the gas-liquid separation efficiency in the integrated valve 14 is improved.

  On the lowermost side of the gas-liquid separation space 141b of the lower body 141, a separated liquid phase refrigerant outlet hole 141c is formed through which the separated liquid phase refrigerant flows out to the liquid phase refrigerant passage 141d side. The liquid-phase refrigerant passage 141d is a refrigerant passage that is disposed below the gas-liquid separation space 141b and guides the liquid-phase refrigerant separated in the gas-liquid separation space 141b to the second and third refrigerant outlets 141e and 141i. is there. The second and third refrigerant outlets 141e and 141i are provided on the bottom surface of the lower body 141. The liquid-phase refrigerant passage 141d branches into a passage 141d1 that communicates with the second refrigerant outlet 141e and a passage 141d2 that communicates with the third refrigerant outlet 141i.

  Inside the liquid-phase refrigerant passage 141d, the liquid-phase refrigerant side valve body 15 that opens and closes the passage 141d1 connected to the second refrigerant outlet 141e in the liquid-phase refrigerant passage 141d, and the passage 141d1 to the liquid-phase refrigerant side valve body 15 A spring (elastic member) 15a made up of a coil spring that applies a load to the closing side is accommodated.

  The spring 15a is a valve formed in a liquid phase refrigerant passage 141d with a resinous annular seal member 15b disposed at the tip of the liquid phase refrigerant side valve body 15 with respect to the liquid phase refrigerant side valve body 15. A load is applied to the seat 141f in a direction to increase the sealing performance. The valve seat 141f is formed in an annular shape that fits the seal member 15b.

  Furthermore, the liquid phase refrigerant side valve body 15 is connected to an operating member (armature) of a solenoid actuator 16 (hereinafter simply referred to as a solenoid) through a shaft 15c. The solenoid 16 is an electromagnetic mechanism that generates an electromagnetic force by supplying electric power to displace the operating member, and its operation is controlled by a control voltage output from the air conditioning control device 40.

  In the present embodiment, when the air-conditioning control device 40 supplies power to the solenoid 16, a load on the side that opens the passage 141d1 is applied to the liquid-phase refrigerant-side valve body 15 via the shaft 15c by electromagnetic force acting on the operating member. Then, when the load due to the electromagnetic force exceeds the load due to the spring 15a, as shown in FIG. 5, the liquid-phase refrigerant side valve body 15 is displaced and continues to the second refrigerant outlet 141e in the liquid-phase refrigerant passage 141d. Open the passage 141d1. Accordingly, the solenoid 16, the liquid-phase refrigerant side valve body 15, the valve seat portion 141f, and the like of the present embodiment constitute a so-called normally closed electromagnetic valve.

  The refrigerant inlet side of the outdoor heat exchanger 20 is connected to the second and third refrigerant outlets 141e and 141i through piping parts 51 to 53 and 61 to 63, respectively. Specifically, as shown in FIGS. 4 and 5, the second refrigerant outlet 141 e is provided with a first joint 51 on the integrated valve side, a first pipe 52, and a first joint 53 on the outdoor heat exchanger side. The first refrigerant inlet 20a of the outdoor heat exchanger 20 is connected. A second refrigerant inlet 20b of the outdoor heat exchanger 20 is connected to the third refrigerant outlet 141i through a second joint 61 on the integrated valve side, a second pipe 62, and a second joint 63 on the outdoor heat exchanger side. Has been.

  The first and second joints 51 and 61 on the integrated valve side are metal parts separate from the lower body 141. The first and second pipes 52 and 62 are separate metal parts from the first and second joints 51 and 61 on the integrated valve side and the first and second joints 53 and 63 on the outdoor heat exchanger side. These are connected by brazing and welding.

  As shown in FIG. 8, the first and second joints 51 and 61 on the integrated valve side are respectively connected to the second and third refrigerant outlets 141e of the lower body 141 via O-rings 51a and 61a as seal members. 141i is directly connected. The first and second joints 51 and 61 on the integrated valve side have internal passages 51b and 61b, respectively.

  Further, as shown in FIG. 8, the integrated valve side second joint 61 connected to the third refrigerant outlet 141i is provided with a fixed throttle 17 in its internal passage 61b. The fixed throttle 17 is integrally formed with the second joint 61 by internal processing of the second joint 61. As the fixed throttle 17, a nozzle or an orifice having a fixed throttle opening is employed. The fixed throttle 17 may be formed as a separate part from the second joint 61, and the fixed throttle 17 may be fixed inside the second joint 61 by press fitting, caulking, or the like.

  As shown in FIG. 4, in the present embodiment, a passage 141d2 connected to the third refrigerant outlet 141i in the liquid phase refrigerant passage 141d is replaced with a passage 141d1 in which the liquid phase refrigerant side valve body 15 is connected to the second refrigerant outlet 141e. When closed, the refrigerant is provided upstream of the refrigerant flow with respect to the inner peripheral passage of the valve seat 141f so that the liquid refrigerant flows out of the third refrigerant outlet 141i.

  For this reason, in a state where the liquid-phase refrigerant side valve body 15 closes the passage 141d1, the liquid-phase refrigerant separated in the gas-liquid separation space 141b flows out from the third refrigerant outlet 141i and is reduced in pressure by the fixed throttle 17. Then, it flows into the outdoor heat exchanger 20.

  On the other hand, the pressure loss that occurs when the refrigerant that has flowed out from the second refrigerant outlet 141 e passes through the piping components 51, 52, and 53 is extremely small compared to the pressure loss that occurs when the refrigerant passes through the fixed throttle 17. Therefore, as shown in FIG. 5, in a state where the liquid phase refrigerant side valve body 15 opens the passage 141d, the liquid phase refrigerant separated in the gas-liquid separation space 141b flows out from the second refrigerant outlet 141e. Thus, it flows into the outdoor heat exchanger 20 with almost no pressure reduction.

  Next, the upper body 142 is formed of a substantially prismatic metal block body having an outer diameter equivalent to that of the lower body 141. In the upper body 142, a gas-phase refrigerant passage 142b that leads the gas-phase refrigerant separated in the gas-liquid separation space 141b to the first refrigerant outlet 142a that flows out of the integrated valve 14 and the gas-liquid separation space 141b and the gas are separated. A separated gas-phase refrigerant outflow pipe portion 142c and the like are provided to communicate with the phase refrigerant passage 142b.

  The separated gas-phase refrigerant outflow pipe portion 142c is formed in a round tubular shape, and is arranged coaxially with the gas-liquid separation space 141b when the upper body 142 and the lower body 141 are integrated. Therefore, the refrigerant that has flowed into the gas-liquid separation space 141b swirls around the separated gas-phase refrigerant outflow pipe portion 142c.

  Further, the lowermost end portion of the separated gas-phase refrigerant outflow pipe portion 142c extends so as to be positioned inside the gas-liquid separation space 141b, and the gas-liquid separation space 141b is separated from the lowermost end portion. A separated gas-phase refrigerant outlet hole 142d through which the phase refrigerant flows out is formed.

  The gas-phase refrigerant passage 142b is disposed above the gas-liquid separation space 141b and the separated gas-phase refrigerant outflow pipe portion 142c, and is perpendicular to the axial direction of the gas-liquid separation space 141b (in this embodiment, the horizontal direction). And is formed by a through-hole having a circular cross section formed so as to pass through the central portion of the upper body 142 and penetrate the side wall surfaces.

  Furthermore, the opening part of the one end side of this through-hole comprises the 1st refrigerant | coolant outflow port 142a. In addition, a gas phase refrigerant side valve element 18 that opens and closes the gas phase refrigerant path 142b is accommodated in the gas phase refrigerant path 142b. The gas-phase refrigerant side valve body 18 is configured by a differential pressure valve that is displaced by a pressure difference between the refrigerant pressure on the second refrigerant outlet 141e side and the refrigerant pressure on the gas-phase refrigerant passage 142b side.

  Specifically, the through-hole forming the gas-phase refrigerant passage 142b is partitioned into a space forming the back-pressure chamber 142e and a space on the gas-phase refrigerant passage 142b side by the body portion 18a of the gas-phase refrigerant side valve body 18. ing. In a state where the liquid-phase refrigerant-side valve body 15 opens the passage 141d1, the refrigerant pressure on the second refrigerant outlet 141e side is guided to the back pressure chamber 142e via the pressure introduction passage 19. In a state where the liquid phase refrigerant side valve body 15 closes the passage 141d, the refrigerant on the outlet side of the fixed throttle 17 is connected to the back pressure chamber 142e via the pressure introduction passage 19, the second refrigerant outlet 141e, and the outdoor heat exchanger 20. Pressure is led.

  The body portion 18a is formed in a cylindrical shape, receives the refrigerant pressure on the gas phase refrigerant passage 142b side at the end surface on the one axial end side (first refrigerant outlet 142a side), and on the end surface on the other axial end side. The refrigerant pressure on the back pressure chamber 142e side is received. Further, the outer diameter of the body portion 18a is slightly smaller than the inner diameter of the gas-phase refrigerant passage 142b, and both are in a clearance fit. Thereby, the gas-phase refrigerant side valve element 18 can be displaced in the gas-phase refrigerant passage 142b.

  The pressure introduction passage 19 is formed by a communication passage formed in both the lower body 141 and the upper body 142 when the upper body 142 and the lower body 141 are integrated. Further, the longitudinal direction of the pressure introduction passage 19 is arranged in parallel with the axial direction of the gas-liquid separation space 141b and the separated gas-phase refrigerant outflow pipe portion 142c. Thereby, the pressure introduction passage 19 is not made into a complicated passage shape, and the integrated valve 14 as a whole is reduced in size.

  Inside the back pressure chamber 142e, there are a spring (elastic member) 18b formed of a coil spring that applies a load to the gas phase refrigerant side valve body 18 on the side where the gas phase refrigerant passage 142b is closed, and the gas phase refrigerant side valve body 18 is in the air. When the phase refrigerant passage 142b is opened, a stopper (regulation member) 18c that regulates the displacement of the gas-phase refrigerant side valve element 18 is accommodated.

  The spring 18b has a tapered shape in which a seal member 18d made of an O-ring disposed at the tip of the gas-phase refrigerant side valve body 18 is formed in the gas-phase refrigerant passage 142b with respect to the gas-phase refrigerant side valve body 18. Is applied to the valve seat portion 142f to increase the sealing performance, that is, the gas-phase refrigerant side valve body 18 applies a load in the direction of closing the gas-phase refrigerant passage 142b.

  The stopper 18c regulates the displacement of the gas-phase refrigerant side valve body 18 to prevent the body portion 18a of the gas-phase refrigerant side valve body 18 from closing the pressure introduction passage 19, and It functions as a closing member that closes the opening on the other end side of the through hole forming the gas-phase refrigerant passage 142b.

  Here, the action | operation of the gaseous-phase refrigerant | coolant side valve body 18 is demonstrated using FIG. First, when power is supplied to the solenoid 16 and the liquid-phase refrigerant side valve body 15 opens the passage 141d1, the gas-phase refrigerant passage 142b indicated by P2 in FIG. 5 is separated in the gas-liquid separation space 141b. The refrigerant pressure in the back pressure chamber 142e indicated by P3 becomes the pressure of the liquid phase refrigerant separated in the gas-liquid separation space 141b.

  Therefore, the refrigerant pressure P2 on the gas phase refrigerant passage 142b side and the refrigerant pressure P3 in the back pressure chamber 142e are substantially equal. As a result, when electric power is supplied to the solenoid 16, the gas-phase refrigerant side valve body 18 closes the gas-phase refrigerant passage 142b with a load received from the spring 18b.

  As shown in FIGS. 1 to 3, the intermediate pressure port 11 b of the compressor 11 is connected to the first refrigerant outlet 142 a of the integrated valve 14. For this reason, when the gas-phase refrigerant side valve body 18 closes the gas-phase refrigerant passage 142b during the operation of the compressor 11, the refrigerant pressure P1 on the first refrigerant outlet 142a side becomes the suction pressure of the compressor 11. Therefore, in FIG. 5, the relationship of P1 <P2 is established.

  For this reason, if the gas-phase refrigerant side valve element 18 closes the gas-phase refrigerant passage 142b during the operation of the compressor 11, there are some fluctuations in the refrigerant pressure P2 in the gas-phase refrigerant passage 142b and the refrigerant pressure P3 in the back pressure chamber 142e. Even if it occurs, the gas-phase refrigerant passage 142b is kept closed until power is not supplied to the solenoid 16.

  Next, when power is not supplied to the solenoid 16 and the liquid-phase refrigerant side valve body 15 closes the passage 141d1, the refrigerant pressure on the first refrigerant outlet 142a side indicated by P1 in FIG. The refrigerant pressure in the gas phase refrigerant passage 142b indicated by P2 becomes the intermediate pressure reduced by the high stage side expansion valve 13, and the refrigerant pressure in the back pressure chamber 142e indicated by P3 is the fixed throttle 17. It becomes the pressure after depressurizing at.

  Therefore, the pressure difference between the refrigerant pressure P2 in the gas-phase refrigerant passage 142b and the refrigerant pressure P3 in the back pressure chamber 142e increases, and the relationship expressed by the following formula is established. The phase refrigerant passage 142b starts to open.

S2 × (P2-P3)> S1 × (P3-P1) + Fsp + Ffr
S1 is an area when the first refrigerant outlet 142a is projected in the axial direction of the gas-phase refrigerant side valve body 18, and S2 is an axial vertical cross section of the body portion 18a of the gas-phase refrigerant side valve body 18. Fsp is a load that the gas-phase refrigerant side valve element 18 receives from the spring 18b, and Ffr is a frictional force (friction) when the gas-phase refrigerant side valve element 18 is displaced.

  When the gas-phase refrigerant side valve element 18 opens the gas-phase refrigerant passage 142b, the refrigerant pressure on the first refrigerant outlet 142a side indicated by P1 in FIG. 4 and the refrigerant pressure in the gas-phase refrigerant passage 142b indicated by P2 are The pressure of the gas-phase refrigerant separated in the liquid separation space 141b becomes the pressure, and the refrigerant pressure in the back pressure chamber 142e indicated by P3 becomes the pressure after being reduced by the fixed throttle 17.

  Accordingly, the refrigerant pressure P3 in the back pressure chamber 142e is lower than the refrigerant pressure P2 in the gas-phase refrigerant passage 142b, and the relationship shown in the following mathematical formula is established. Is kept open.

S2 × (P2-P3)> Fsp
Note that the refrigerant piping from the first refrigerant outlet 142a of the integrated valve 14 to the intermediate pressure port 11b of the compressor 11 only allows the refrigerant to flow from the integrated valve 14 to the intermediate pressure port 11b of the compressor 11. Not check valve is arranged. This prevents the refrigerant from flowing backward from the compressor 11 side to the integrated valve 14 side. Of course, this check valve may be integrated with the integrated valve 14 or the compressor 11.

  The outdoor heat exchanger 20 shown in FIGS. 1-3 is arrange | positioned in a bonnet, and heat-exchanges the refrigerant | coolant which distribute | circulates an inside and the external air ventilated from the ventilation fan 21. As shown in FIG. The outdoor heat exchanger 20 functions as an evaporator that evaporates the low-pressure refrigerant and exerts an endothermic effect at least in the heating operation mode (first and second heating modes), and in the cooling operation mode and the like. It is a heat exchanger that functions as a heat radiator that dissipates high-pressure refrigerant.

  Moreover, as shown in FIGS. 1-3, the refrigerant | coolant inlet side of the expansion valve 22 for a cooling as a 2nd pressure reduction means is connected to the refrigerant | coolant outlet side of the outdoor heat exchanger 20. As shown in FIG. The cooling expansion valve 22 depressurizes the refrigerant that flows out of the outdoor heat exchanger 20 and flows into the indoor evaporator 23 in the cooling operation mode or the like. The basic configuration of the cooling expansion valve 22 is the same as that of the high-stage expansion valve 13, and its operation is controlled by a control signal output from the air conditioning control device 40.

  The refrigerant inlet side of the indoor evaporator 23 is connected to the outlet side of the cooling expansion valve 22. The indoor evaporator 23 is arranged in the air conditioning case 31 of the indoor air conditioning unit 30 on the upstream side of the blower air flow of the indoor condenser 12, and evaporates the refrigerant that circulates in the cooling operation mode, the dehumidifying heating operation mode, and the like. It is a heat exchanger that functions as an evaporator that cools the blown air by causing it to exhibit an endothermic effect.

  The outlet side of the indoor evaporator 23 is connected to the inlet side of the accumulator 24. The accumulator 24 is a low-pressure side gas-liquid separator that separates the gas-liquid refrigerant flowing into the accumulator 24 and stores excess refrigerant. Furthermore, the suction port 11 a of the compressor 11 is connected to the gas phase refrigerant outlet of the accumulator 24. Therefore, the indoor evaporator 23 is connected so as to flow out to the suction port 11 a side of the compressor 11.

  Furthermore, on the refrigerant outlet side of the outdoor heat exchanger 20, an expansion valve bypass passage that guides the refrigerant flowing out of the outdoor heat exchanger 20 to the inlet side of the accumulator 24 while bypassing the cooling expansion valve 22 and the indoor evaporator 23. 25 is connected. A bypass passage opening / closing valve 27 is disposed in the expansion valve bypass passage 25.

  The bypass passage opening / closing valve 27 is an electromagnetic valve that opens and closes the expansion valve bypass passage 25, and its opening / closing operation is controlled by a control voltage output from the air conditioning control device 40. Further, the pressure loss that occurs when the refrigerant passes through the bypass passage opening / closing valve 27 is extremely small with respect to the pressure loss that occurs when the refrigerant passes through the cooling expansion valve 22.

  Therefore, the refrigerant flowing out of the outdoor heat exchanger 20 flows into the accumulator 24 through the expansion valve bypass passage 25 when the bypass passage opening / closing valve 27 is open. At this time, the throttle opening of the cooling expansion valve 22 may be fully closed.

  Further, when the bypass passage opening / closing valve 27 is closed, it flows into the indoor evaporator 23 through the cooling expansion valve 22. Thereby, the bypass passage opening / closing valve 27 can switch the refrigerant circuit of the heat pump cycle 10. Therefore, the bypass passage opening / closing valve 27 of this embodiment constitutes a refrigerant circuit switching means together with the integrated valve 14.

  Next, the indoor air conditioning unit 30 will be described. The indoor air conditioning unit 30 is arranged inside the instrument panel (instrument panel) at the foremost part of the vehicle interior, forms an outer shell of the indoor air conditioning unit 30, and air blown into the interior of the vehicle interior. It has an air conditioning case 31 that forms a passage. And the air blower 32, the above-mentioned indoor condenser 12, the indoor evaporator 23, etc. are accommodated in this air passage.

  On the most upstream side of the air flow in the air conditioning case 31, an inside / outside air switching device 33 that switches between introduction of inside air and outside air is arranged. On the downstream side of the air flow of the inside / outside air switching device 33, a blower 32 that blows air sucked through the inside / outside air switching device 33 toward the vehicle interior is arranged. The blower 32 is an electric blower that drives a centrifugal multiblade fan with an electric motor, and the number of rotations (the amount of blown air) is controlled by a control voltage output from the air conditioning control device 40.

  On the downstream side of the air flow of the blower 32, the indoor evaporator 23 and the indoor condenser 12 described above are arranged in the order of the indoor evaporator 23 → the indoor condenser 12 with respect to the flow of the blown air. In other words, the indoor evaporator 23 is disposed on the upstream side of the air flow with respect to the indoor condenser 12.

  Further, a bypass passage 35 is provided in the air conditioning case 31 to flow the blown air after passing through the indoor evaporator 23, bypassing the indoor condenser 12, on the downstream side of the air flow of the indoor evaporator 23. And the air mix door 34 is arrange | positioned in the air flow upstream of the indoor condenser 12. FIG.

  The air mix door 34 adjusts the air volume ratio between the air volume that passes through the indoor condenser 12 and the air volume that passes through the bypass passage 35 among the air that has passed through the indoor evaporator 23, thereby condensing the indoor air. This is a flow rate adjusting means for adjusting the flow rate (air volume) of the blown air flowing into the condenser 12, and functions to adjust the heat exchange capacity of the indoor condenser 12.

  Further, on the downstream side of the air flow of the indoor condenser 12 and the bypass passage 35, blown air heated by exchanging heat with the refrigerant in the indoor condenser 12 and blown air not heated through the bypass passage 35 are present. A merge space 36 for merging is provided.

  An opening hole is provided in the most downstream portion of the air flow case 31 of the air conditioning case 31 to blow the blown air merged in the merge space 36 into the vehicle interior that is the air conditioning target space. Specifically, as this opening hole, a defroster opening hole 37a that blows conditioned air toward the inner side surface of the vehicle front window glass, a face opening hole 37b that blows conditioned air toward the upper body of the passenger in the passenger compartment, and the feet of the passenger The foot opening hole 37c which blows air-conditioning wind toward is provided.

  Therefore, the air mix door 34 adjusts the air volume ratio between the air volume passing through the indoor condenser 12 and the air volume passing through the bypass passage 35, thereby adjusting the temperature of the blown air in the merge space 36. The air mix door 34 is driven by a servo motor (not shown) whose operation is controlled by a control signal output from the air conditioning controller 40.

  Further, on the upstream side of the air flow of the defroster opening hole 37a, the face opening hole 37b, and the foot opening hole 37c, the opening areas of the defroster door 38a and the face opening hole 37b for adjusting the opening area of the defroster opening hole 37a are adjusted. A foot door 38c for adjusting the opening area of the face door 38b and the foot opening hole 37c is disposed. These defroster doors 38a, face doors 38b, and foot doors 38c constitute the outlet mode switching means that opens and closes the respective opening holes 37a to 37c and switches the outlet mode, and through a link mechanism or the like, It is driven by a servo motor (not shown) whose operation is controlled by a control signal output from the air conditioning controller 40.

  In addition, the air flow downstream side of the defroster opening hole 37a, the face opening hole 37b, and the foot opening hole 37c is respectively connected to a face air outlet, a foot air outlet, and a defroster air outlet provided in the vehicle interior via ducts that form air passages. Connected to the exit.

  Next, the electric control unit of this embodiment will be described. The air conditioning control device 40 includes a known microcomputer including a CPU, a ROM, a RAM, and the like and peripheral circuits thereof. The air conditioning control device 40 performs various calculations and processes based on the air conditioning control program stored in the ROM, and controls the operation of various air conditioning control devices connected to the output side.

  Further, on the input side of the air conditioning control device 40, an inside air sensor that detects the temperature inside the vehicle, an outside air sensor that detects the outside air temperature, a solar radiation sensor that detects the amount of solar radiation in the vehicle interior, and the temperature of air blown from the indoor evaporator 23 ( An evaporator temperature sensor for detecting the evaporator temperature), a discharge pressure sensor for detecting the high-pressure refrigerant pressure discharged from the compressor 11, a condenser temperature sensor for detecting the temperature of the refrigerant flowing out of the indoor condenser 12, and the compressor 11 Various air-conditioning control sensor groups 41 such as a suction pressure sensor for detecting the suction refrigerant pressure sucked in are connected.

  Furthermore, an operation panel (not shown) disposed near the instrument panel in the front of the passenger compartment is connected to the input side of the air conditioning control device 40, and operation signals from various air conditioning operation switches provided on the operation panel are input. The Specifically, various air conditioning operation switches provided on the operation panel include an operation switch of the vehicle air conditioner 1, a vehicle interior temperature setting switch for setting the vehicle interior temperature, a cooling operation mode, a dehumidifying heating operation mode, and a heating operation mode. A mode selection switch or the like for selecting is provided.

  Next, the operation of the vehicle air conditioner 1 of the present embodiment having the above configuration will be described. The vehicle air conditioner 1 according to the present embodiment performs any one of the cooling operation mode, the heating operation mode, and the dehumidifying heating mode, similarly to the vehicle air conditioner described in Patent Document 1. The operation in each operation mode will be described below.

(A) Cooling operation mode The cooling operation mode is started when the operation switch of the operation panel is turned on (ON) and the cooling operation mode is selected by the selection switch.

  In the cooling operation mode, the air conditioning control device 40 fully opens the high stage side expansion valve 13, sets the solenoid 16 of the integrated valve 14 to the energized state, sets the cooling expansion valve 22 to a throttled state that exerts a pressure reducing action, The bypass passage opening / closing valve 27 is closed.

  Thereby, as shown in FIG. 5, the integrated valve 14 opens the channel | path 141d1 which the liquid phase refrigerant | coolant side valve body 15 continues to the 2nd refrigerant | coolant outflow port 141e among the liquid phase refrigerant paths 141d, and the gaseous-phase refrigerant | coolant side valve body 18 Closes the gas-phase refrigerant passage 142b. The heat pump cycle 10 is switched to a refrigerant circuit through which a refrigerant flows as shown by solid line arrows in FIG.

  With this refrigerant circuit configuration, the air conditioning control device 40 reads the detection signal of the air conditioning control sensor group 41 and the operation signal of the operation panel, and the air blown into the vehicle interior based on the value of the detection signal and the operation signal. A target blowing temperature TAO that is a target temperature is calculated. Further, the air conditioning control device 40 determines the operating state of various air conditioning control devices based on the calculated target blowout temperature TAO and the detection signal of the sensor group, and outputs the determined control signals and the like to the various air conditioning control devices. .

  For example, the refrigerant discharge capacity of the compressor 11, that is, the control signal output to the electric motor of the compressor 11 is determined as follows. First, the target evaporator outlet temperature TEO of the indoor evaporator 23 is determined based on the target outlet temperature TAO with reference to a control map stored in the air conditioning controller 40 in advance. And based on the deviation of this target evaporator blowing temperature TEO and the blowing air temperature from the indoor evaporator 23 detected by the evaporator temperature sensor, the blowing air temperature from the indoor evaporator 23 is determined using a feedback control method. A control signal output to the electric motor of the compressor 11 is determined so as to approach the target evaporator outlet temperature TEO.

  As for the control signal output to the cooling expansion valve 22, the supercooling degree of the refrigerant flowing into the cooling expansion valve 22 approaches the target supercooling degree determined in advance so that the COP approaches a substantially maximum value. To be determined.

  Regarding the control signal output to the servo motor of the air mix door 34, the air mix door 34 closes the air passage of the indoor condenser 12, and the total flow rate of the blown air after passing through the indoor evaporator 23 is the bypass passage 35. Is determined to pass.

  Therefore, in the heat pump cycle 10 in the cooling operation mode, the high-pressure refrigerant discharged from the discharge port 11c of the compressor 11 flows into the indoor condenser 12, as shown in FIG. At this time, since the air mix door 34 closes the air passage of the indoor condenser 12, the refrigerant flowing into the indoor condenser 12 flows out of the indoor condenser 12 without radiating heat to the vehicle interior air. Go. Since the high-stage side expansion valve 13 is fully opened, the refrigerant that has flowed out from the indoor condenser 12 flows out with almost no pressure reduction at the high-stage side expansion valve 13, and the refrigerant inlet 141 a of the integrated valve 14. Flows into the gas-liquid separation space 141b.

  Since the refrigerant flowing into the integrated valve 14 is in a gas phase state having superheat, the gas-liquid refrigerant is not separated in the gas-liquid separation space 141b of the integrated valve 14, and the gas-phase refrigerant is in the liquid-phase refrigerant passage. It flows into 141d. Further, the gas-phase refrigerant flowing into the liquid-phase refrigerant passage 141d flows out from the second refrigerant outlet 141e because the liquid-phase refrigerant-side valve body 15 opens the passage 141d1 connected to the second refrigerant outlet 141e. It flows into the outdoor heat exchanger 20. That is, the refrigerant flowing out of the integrated valve 14 flows into the outdoor heat exchanger 20 with almost no pressure loss. At this time, since the refrigerant pressure on the second refrigerant outlet 141e side is guided to the back pressure chamber 142e via the pressure introduction passage 19, the gas phase refrigerant side valve element 18 closes the gas phase refrigerant passage 142b. Therefore, the refrigerant does not flow out from the first refrigerant outlet 142a.

  The refrigerant flowing into the outdoor heat exchanger 20 exchanges heat with the outside air blown from the blower fan 21 to radiate heat. The refrigerant flowing out of the outdoor heat exchanger 20 is isoenthalpy until it flows into the cooling expansion valve 22 in the throttled state and becomes a low-pressure refrigerant because the bypass passage opening / closing valve 27 is closed. Inflated to a reduced pressure.

  Then, the low-pressure refrigerant decompressed by the cooling expansion valve 22 flows into the indoor evaporator 23, absorbs heat from the indoor air blown from the blower 32, and evaporates. As a result, the vehicle interior air is cooled, and the cooled air is blown out into the vehicle interior.

  The refrigerant flowing out of the indoor evaporator 23 flows into the accumulator 24 and is separated into gas and liquid. The separated gas-phase refrigerant is sucked from the suction port 11a of the compressor 11 and compressed again in the order of the low-stage compression mechanism → the high-stage compression mechanism. On the other hand, the separated liquid-phase refrigerant is stored in the accumulator 24 as surplus refrigerant that is not necessary for exhibiting the refrigerating capacity required for the cycle.

(B) Heating operation mode Next, heating operation mode is demonstrated. As described above, in the heat pump cycle 10 of the present embodiment, the first heating mode and the second heating mode can be executed as the heating operation mode. First, the heating operation mode is started when the heating operation mode is selected by the selection switch while the operation switch of the vehicle air conditioner is turned on.

  When the heating operation mode is started, the air conditioning control device 40 reads the detection signal of the air conditioning control sensor group 41 and the operation signal of the operation panel, and the refrigerant discharge capacity of the compressor 11 (the rotation speed of the compressor 11). To decide. Further, the first heating mode or the second heating mode is executed according to the determined rotation speed.

(B) -1: First Heating Mode First, the first heating mode will be described. When the first heating mode is executed, the air-conditioning control device 40 puts the high stage side expansion valve 13 into a throttled state, puts the solenoid 16 of the integrated valve 14 into a non-energized state, puts the cooling expansion valve 22 into a fully closed state, Further, the bypass passage opening / closing valve 27 is opened.

  Thereby, as shown in FIG. 4, the integrated valve 14 closes the passage 141d1 of the liquid-phase refrigerant side valve body 15 that is connected to the second refrigerant outlet 141e in the liquid-phase refrigerant path 141d, and the gas-phase refrigerant-side valve body 18 Will open the gas-phase refrigerant passage 142b. The heat pump cycle 10 is switched to the refrigerant flow path through which the refrigerant flows as shown by the solid arrows in FIG.

  With this refrigerant flow path configuration (cycle configuration), the air-conditioning control device 40 reads the detection signal of the air-conditioning control sensor group 41 and the operation signal of the operation panel, as in the cooling operation mode, and the target blowing temperature TAO and the sensor group. Based on this detection signal, the operating states of various air conditioning control devices are determined, and the determined control signals and the like are output to various air conditioning control devices.

In the first heating mode, the control signal output to the high stage side expansion valve 13 flows out from the indoor condenser 12 so that the refrigerant pressure in the indoor condenser 12 becomes a predetermined target high pressure. The degree of supercooling of the refrigerant is determined to be a predetermined target degree of supercooling. For the control signal output to the servo motor of the air mix door 34, the air mix door 34 closes the bypass passage 35, and the entire flow rate of the blown air after passing through the indoor evaporator 23 passes through the indoor condenser 12. Accordingly, in the heat pump cycle 10 in the first heating mode, the high-pressure refrigerant discharged from the discharge port 11c of the compressor 11 flows into the indoor condenser 12 as shown by the solid line arrow in FIG. The refrigerant that has flowed into the indoor condenser 12 exchanges heat with the vehicle interior blown air that has been blown from the blower 32 and passed through the indoor evaporator 23 to dissipate heat. Thereby, the vehicle interior air is heated, and the heated vehicle interior air is blown into the vehicle interior.

  The refrigerant that has flowed out of the indoor condenser 12 is decompressed and expanded in an enthalpy manner until it becomes an intermediate-pressure refrigerant by the high-stage expansion valve 13 that is in a throttled state. Then, the intermediate pressure refrigerant decompressed by the high-stage side expansion valve 13 flows into the gas-liquid separation space 141b from the refrigerant inlet 141a of the integrated valve 14 and is separated into gas and liquid.

  The liquid phase refrigerant separated in the gas-liquid separation space 141b flows into the liquid phase refrigerant passage 141d. The liquid-phase refrigerant that has flowed into the liquid-phase refrigerant passage 141d has the third refrigerant outlet 141i because the liquid-phase refrigerant-side valve body 15 closes the passage 141d1 connected to the second refrigerant outlet 141e in the liquid-phase refrigerant passage 141d. It flows out from the third refrigerant outlet 141i through a passage 141d2 connected to the first refrigerant outlet 141d2. The liquid-phase refrigerant that has flowed out of the third refrigerant outlet 141i is decompressed and expanded in an enthalpy manner until it becomes a low-pressure refrigerant in the fixed throttle 17, and flows into the outdoor heat exchanger 20.

  At this time, the refrigerant pressure after being depressurized by the fixed throttle 17 is guided to the back pressure chamber 142e via the outdoor heat exchanger 20, the second refrigerant outlet 141e, and the pressure introduction passage 19, so that the gas phase refrigerant The side valve body 18 opens the gas-phase refrigerant passage 142b. Therefore, the gas-phase refrigerant separated in the gas-liquid separation space 141 b flows out from the first refrigerant outlet 142 a of the integrated valve 14 and flows into the intermediate pressure port 11 b side of the compressor 11. The intermediate-pressure gas-phase refrigerant flowing into the intermediate-pressure port 11b joins with the low-stage compression mechanism discharge refrigerant and is sucked into the high-stage compression mechanism.

  The refrigerant that has flowed into the outdoor heat exchanger 20 exchanges heat with the outside air blown from the blower fan 21 to absorb heat, and flows out of the outdoor heat exchanger 20. The refrigerant flowing out of the outdoor heat exchanger 20 flows into the accumulator 24 through the expansion valve bypass passage 25 and is separated into gas and liquid because the bypass passage opening / closing valve 27 is in the open state. The separated gas-phase refrigerant is sucked from the suction port 11a of the compressor 11 and compressed again. On the other hand, the separated liquid-phase refrigerant is stored in the accumulator 24 as surplus refrigerant that is not necessary for exhibiting the refrigerating capacity required for the cycle.

  As described above, in the first heating mode, the low-pressure refrigerant depressurized by the fixed throttle 17 is sucked from the suction port 11a of the compressor 11, and the intermediate-pressure refrigerant depressurized by the high stage side expansion valve 13 is used as the intermediate pressure port. A gas injection cycle (economizer refrigeration cycle) that flows into 11b and joins with the refrigerant in the pressure increasing process can be configured.

  This allows the high-stage compression mechanism to suck the low-temperature mixed refrigerant, improves the compression efficiency of the high-stage compression mechanism, and reduces the low-stage compression mechanism and the high-stage compression mechanism. By reducing the pressure difference between the suction refrigerant pressure and the discharge refrigerant pressure, the compression efficiency of both compression mechanisms can be improved. As a result, the COP of the heat pump cycle 10 as a whole can be improved.

(B) -2: Second Heating Mode Next, the second heating mode will be described. When the second heating mode is executed, the air-conditioning control device 40 sets the high stage side expansion valve 13 to the throttle state, sets the solenoid 16 of the integrated valve 14 to the energized state, sets the cooling expansion valve 22 to the fully closed state, Then, the bypass passage opening / closing valve 27 is opened. As a result, the integrated valve 14 is in the state shown in FIG. 5 as in the cooling operation mode, and the heat pump cycle 10 is switched to the refrigerant flow path through which the refrigerant flows as shown by the solid line arrows in FIG.

  With this refrigerant flow path configuration (cycle configuration), the air-conditioning control device 40 reads the detection signal of the air-conditioning control sensor group 41 and the operation signal of the operation panel, as in the cooling operation mode, and the target blowing temperature TAO and the sensor group. Based on this detection signal, the operating states of various air conditioning control devices are determined, and the determined control signals and the like are output to the various air conditioning control devices.

  In the second heating mode, the control signal output to the high stage side expansion valve 13 flows out from the indoor condenser 12 so that the refrigerant pressure in the indoor condenser 12 becomes a predetermined target high pressure. The degree of supercooling of the refrigerant to be set is determined to be a predetermined target supercooling degree. For the control signal output to the servo motor of the air mix door 34, the air mix door 34 closes the bypass passage 35, and the entire flow rate of the blown air after passing through the indoor evaporator 23 passes through the indoor condenser 12. To be determined.

  Therefore, in the heat pump cycle 10 in the second heating mode, as shown by the solid line arrow in FIG. 3, the high-pressure refrigerant discharged from the discharge port 11c of the compressor 11 flows into the indoor condenser 12, and in the first heating mode. Similarly, heat is exchanged with the air blown into the passenger compartment to dissipate heat. Thereby, the vehicle interior air is heated, and the heated vehicle interior air is blown into the vehicle interior.

  The refrigerant flowing out of the indoor condenser 12 is decompressed and expanded in an enthalpy manner until it becomes a low-pressure refrigerant in the throttled high-stage expansion valve 13 and flows into the gas-liquid separation space 141b of the integrated valve 14. To do. The refrigerant that has flowed into the gas-liquid separation space 141b flows out of the second refrigerant outlet 141e and flows into the outdoor heat exchanger 20, as in the cooling operation mode.

  The low-pressure refrigerant that has flowed into the outdoor heat exchanger 20 exchanges heat with the outside air blown from the blower fan 21, absorbs heat, and flows out of the outdoor heat exchanger 20. The refrigerant flowing out of the outdoor heat exchanger 20 flows into the accumulator 24 through the expansion valve bypass passage 25 and is separated into gas and liquid because the bypass passage opening / closing valve 27 is in the open state. The separated gas-phase refrigerant is sucked from the suction port 11a of the compressor 11.

  Here, the effect of executing the second heating mode when the heating load is relatively low, such as when the outside air temperature is high, is described with respect to the first heating mode. In the first heating mode, since the gas injection cycle can be configured as described above, the COP of the heat pump cycle 10 as a whole can be improved.

  That is, theoretically, if the rotation speed of the compressor 11 is the same, the first heating mode can exhibit higher heating performance than that in the second heating mode. In other words, the rotation speed (refrigerant discharge capacity) of the compressor 11 necessary for exhibiting the same heating performance is lower in the first heating mode than in the second heating mode.

  However, the compression mechanism has a maximum efficiency rotational speed at which the compression efficiency is maximized (peak), and the compression efficiency is greatly reduced when the rotational speed is lower than the maximum efficient rotational speed. For this reason, when the compressor 11 is operated at a rotation speed lower than the maximum efficiency rotation speed when the heating load is relatively low, the COP may decrease in the first heating mode.

  Therefore, in the present embodiment, when the rotation speed of the compressor 11 becomes equal to or less than the reference rotation speed during execution of the first heating mode with the above-described maximum efficiency rotation speed as the reference rotation speed, the second heating mode is entered. Switching to the first heating mode is performed when the rotation speed becomes equal to or higher than the rotation speed obtained by adding a predetermined amount to the reference rotation speed during execution of the second heating mode.

  Thereby, the operation mode which can exhibit high COP can be selected among 1st heating mode and 2nd heating mode. Therefore, even when the rotation speed of the compressor 11 becomes equal to or lower than the reference rotation speed during the execution of the first heating mode, the COP of the heat pump cycle 10 as a whole is improved by switching to the second heating mode. Can be made.

(C) Dehumidification heating operation mode Next, the dehumidification heating operation mode is demonstrated. The dehumidifying and heating operation mode is executed when the set temperature set by the vehicle interior temperature setting switch in the cooling operation mode is set to a temperature higher than the outside air temperature.

  When the dehumidifying and heating mode is executed, the air-conditioning control device 40 sets the high stage side expansion valve 13 to a fully open state or throttled state, sets the solenoid 16 of the integrated valve 14 to an energized state, and sets the cooling expansion valve 22 to a fully open state or throttle. Further, the bypass passage opening / closing valve 27 is closed. As a result, the heat pump cycle 10 is switched to the refrigerant flow path through which the refrigerant flows as shown by the solid line arrows in FIG. 1 similar to the cooling operation mode.

  With this refrigerant flow path configuration (cycle configuration), the air-conditioning control device 40 reads the detection signal of the air-conditioning control sensor group 41 and the operation signal of the operation panel, as in the cooling operation mode, and the target blowing temperature TAO and the sensor group. Based on this detection signal, the operating states of various air conditioning control devices are determined, and the determined control signals and the like are output to the various air conditioning control devices.

  For example, with respect to the control signal output to the servo motor of the air mix door 34, as shown by the broken line in FIG. 1, the air mix door 34 closes the bypass passage 35 and the blown air after passing through the indoor evaporator 23. The total flow rate is determined to pass through the indoor condenser 12.

  With respect to the control signal output to the high stage side expansion valve 13 and the cooling expansion valve 22, the high stage side expansion valve 13 and the cooling expansion valve 22 are fully opened or not according to the temperature difference between the set temperature and the outside temperature. It is determined so as to be in the aperture state. As an example, it is determined that the high stage side expansion valve 13 is fully opened and the cooling expansion valve 22 is in the throttle state.

  Therefore, in the heat pump cycle 10 in the dehumidifying and heating mode, as shown by the solid line arrow in FIG. 1, the high-pressure refrigerant discharged from the discharge port 11 c of the compressor 11 flows into the indoor condenser 12, and the indoor evaporator 23 The heat is exchanged with the air blown into the passenger compartment that has been cooled and dehumidified in order to radiate heat. Thereby, vehicle interior blowing air is heated.

  The refrigerant that has flowed out of the indoor condenser 12 flows in the order of the high-stage expansion valve 13 → the integrated valve 14 and flows into the outdoor heat exchanger 20 in the same manner as in the cooling operation mode. The high-pressure refrigerant that has flowed into the outdoor heat exchanger 20 exchanges heat with the outside air blown from the blower fan 21 to dissipate heat. The subsequent operation is the same as in the cooling operation mode.

  As described above, in the dehumidifying and heating mode, the vehicle interior blown air cooled and dehumidified by the indoor evaporator 23 can be heated by the indoor condenser 12 and blown out into the vehicle interior. Thereby, dehumidification heating of a vehicle interior is realizable.

  Next, the effect of this embodiment will be described.

  In the present embodiment, the fixed throttle 17 is provided in the internal passage of the second joint 61 that is a piping component. In the first heating mode, the refrigerant is depressurized by the fixed throttle 17, so that the temperature of the refrigerant after passing through the fixed throttle 17 becomes lower than the temperature of the refrigerant inside the body 140. For this reason, in the first heating mode, the low-temperature refrigerant after passing through the fixed throttle 17 flows through the second joint 61 and the second pipe 62.

  Thus, in this embodiment, since the fixed throttle 17 is located outside the body 140, it is possible to keep the low-temperature refrigerant after passing through the fixed throttle 17 away from the body 140 so that it does not come into direct contact with the body 140. . Furthermore, since the second joint 61 is separate from the body 140 and the second joint 61 and the body 140 are connected via the O-ring 61a, there is a gap between the second joint 61 and the body 140. Arise. Therefore, the thermal resistance between the second joint 61 and the body 140 is higher than in the case where the components of the fixed throttle outlet flow path are integrated with the body 140, that is, continuously formed of the same material. It has become. Thereby, the amount of heat exchange between the low-temperature refrigerant after passing through the fixed throttle 17 via the second joint 61 and the body 140 and the high-temperature refrigerant inside the body 140 can be significantly reduced.

  Therefore, according to the present embodiment, in the first heating mode, the amount of heat exchange between the refrigerant after passing through the fixed throttle 17 and the high-temperature refrigerant inside the body 140 can be reduced as compared with the conventional technique, and the heating is performed more than the conventional technique. A decrease in ability can be suppressed.

  In the present embodiment, the second joint 61 is in contact with only the peripheral portion of the third refrigerant outlet 141i on the outer surface of the body 140, and the contact area between the second joint 61 and the body 140 is small. Also contributes to a reduction in the amount of heat exchange.

  Moreover, in this embodiment, since the fixed throttle 17 is provided in the 2nd coupling 61 directly connected to the integrated valve 14 and integrated with the integrated valve 14, vehicle mounting property does not deteriorate compared with a prior art. . Incidentally, also in the prior art in which a fixed throttle is provided inside the integrated valve, a joint for connecting the integrated valve and the pipe is directly connected to the integrated valve.

  Moreover, according to this embodiment, the assembly | attachment property of the integrated valve 14 and the fixed throttle 17 can be improved rather than a prior art, suppressing the fall of a heating capability rather than a prior art. That is, in the prior art described in Patent Documents 1 and 2, before assembling the joint for connecting the integrated valve and the pipe to the integrated valve, the step of inserting the resin part in which the fixed throttle is formed into the integrated valve Was necessary. On the other hand, in the present embodiment, if the first and second joints 51 and 61 on the integrated valve side are assembled to the integrated valve 14, the assembly of the integrated valve 14 and the fixed throttle 17 is completed, so the resin part is inserted. The process to do can be made unnecessary.

(Second Embodiment)
In the present embodiment, the installation location of the fixed diaphragm 17 is changed with respect to the first embodiment. Other configurations are the same as those of the first embodiment.

  As shown in FIG. 9, in this embodiment, a fixed throttle is provided in the pipe 62 among the pipe parts 61, 62, and 63 that constitute the refrigerant passage from the third refrigerant outlet 141 i to the refrigerant inlet of the outdoor heat exchanger 20. 17 is provided. The fixed throttle 17 is formed in the internal passage 64 a of the connection component 64 connected in the middle of the pipe 62.

  Also in this embodiment, since the fixed throttle 17 is provided in the piping parts located outside the body 140, the same effects as those of the first embodiment can be obtained.

(Third embodiment)
In the present embodiment, the installation location of the fixed diaphragm 17 is changed with respect to the first embodiment. Other configurations are the same as those of the first embodiment.

  As shown in FIG. 10, in the present embodiment, the outdoor heat exchanger side among the piping components 61, 62, and 63 that constitute the refrigerant passage from the third refrigerant outlet 141 i to the refrigerant inlet of the outdoor heat exchanger 20. The fixed throttle 17 is provided in the internal passage 63 a of the second joint 63. Also in this embodiment, since the fixed throttle 17 is provided in the piping parts located outside the body 140, the same effects as those of the first embodiment can be obtained.

(Fourth embodiment)
In the present embodiment, the first and second joints 51 and 61 on the integrated valve side in the first embodiment are integrated. As shown in FIG. 11, in the present embodiment, the second and third refrigerant outlets 141e and 141i of the integrated valve 14 are connected to the outdoor heat exchanger 20 via one refrigerant passage.

  As shown in FIG. 12, one integrated valve side joint 71 is directly connected to the second and third refrigerant outlets 141e and 141i of the lower body 141. One pipe 72 is connected to the joint 71 on the integrated valve side, and the refrigerant inlet side of the outdoor heat exchanger 20 is connected to the pipe 72. The joint 71 on the integrated valve side connects one pipe 72 to the second refrigerant outlet 141e and the third refrigerant outlet 141i. The joint 71 on the integrated valve side includes a portion directly connected to the second refrigerant outlet 141e and a portion directly connected to the third refrigerant outlet 141i as an integral part.

  More specifically, as shown in FIG. 13, the joint 71 on the integrated valve side includes, as internal passages, a first internal passage 71 a through which refrigerant flowing out from the second refrigerant outlet 141 e flows and a third refrigerant outlet 141 i. The second internal passage 71b through which the refrigerant flowing out of the refrigerant flows and the third internal passage 71c connected to the pipe 72 are connected to the third internal passage 71c. The joint 71 on the integrated valve side is configured such that the portions constituting these passages 71a, 71b, 71c are continuous integrated parts made of metal.

  In the joint 71 on the integrated valve side, the fixed throttle 17 is provided in the second internal passage 71b. The fixed throttle 17 is integrally formed with the joint 71 by internal processing of the joint 71. The fixed throttle 17 may be formed as a separate part from the joint 71, and the fixed throttle 17 may be fixed inside the joint 71 by press fitting, caulking, or the like.

  A portion constituting the first internal passage 71a is inserted into the second refrigerant outlet 141e, and is sealed by an O-ring 71d as a seal member. Similarly, the part which comprises the 2nd internal channel | path 71b is inserted in the 3rd refrigerant | coolant outflow port 141i, and is sealed by O-ring 71e as a sealing member.

  Also in this embodiment, since the fixed throttle 17 is provided in the joint 71 on the integrated valve side as a piping component located outside the body 140, the same effects as in the first embodiment can be obtained.

  In the present embodiment, since the joint 71 on the integrated valve side that connects one pipe 72 to the second refrigerant outlet 141e and the third refrigerant outlet 141i is used, the integrated valve 14 and the outdoor heat exchanger 20 are used. One pipe is sufficient to connect the two.

(Fifth embodiment)
In the present embodiment, the shape of the second joint 61 on the integrated valve side is partially changed with respect to the first embodiment.

  As shown in FIG. 14, the second joint 61 on the integrated valve side has a recess 61 c that forms a gap between the second joint 61 and the outer surface of the body 140. The recess 61 c is formed in a portion of the outer surface of the body 140 that faces the peripheral portion of the third refrigerant outlet 141 i.

  For this reason, in the present embodiment, a gap is formed between the body 140 and the second joint 61 on the integrated valve side in a state where the integrated valve side second joint 61 is directly connected to the integrated valve 14. Thereby, compared with the case where it does not have the recessed part 61c, both the contact area of the body 140 and the 2nd coupling 61 by the side of the integrated valve can be made small, and the thermal resistance between both can be increased.

  Therefore, according to the present embodiment, in the first heating mode in which the refrigerant is decompressed by the fixed throttle 17, heat transfer between the refrigerant after passing through the fixed throttle 17 and the refrigerant inside the body 140 can be further suppressed. A decrease in ability can be further suppressed.

(Sixth embodiment)
In the present embodiment, the shape of the joint 71 on the integrated valve side is partially changed as in the fifth embodiment with respect to the fourth embodiment.

  As shown in FIG. 15, the joint 71 on the integrated valve side is a recess 71 f that forms a gap with the integrated valve 14 at a portion facing the outer surface of the body 140 of the integrated valve 14 as in the fifth embodiment. have. The recess 71f is formed in a portion of the outer surface of the body 140 that faces the peripheral portion of the second refrigerant outlet 141e and the peripheral portion of the third refrigerant outlet 141i.

  For this reason, in this embodiment as well, as in the fifth embodiment, a gap is formed between the body 140 and the joint 71 in a state where the joint 71 on the integrated valve side is directly connected to the integrated valve 14. The same effects as in the fifth embodiment are achieved.

(Seventh embodiment)
In the present embodiment, a member having a high thermal resistance is added between the integrated valve 14 and the second joint 61 on the integrated valve side with respect to the first embodiment.

  As shown in FIG. 16, a member 61 d having a higher thermal resistance than the body 140 and the second joint 61 is disposed between the body 140 of the integrated valve 14 and the second joint 61 on the integrated valve side. The member 61d is disposed in a recess formed in a portion of the outer surface of the body 140 that faces the peripheral portion of the third refrigerant outlet 141i. Examples of the member 61d include materials having lower thermal conductivity than metals, such as rubber and resin.

  For this reason, in the present embodiment, in the state where the integrated valve-side second joint 61 is directly connected to the integrated valve 14, the body 140 and the integrated valve-side second are compared with the case where the member 61d is not provided. The thermal resistance between the joints 61 increases. Therefore, according to the present embodiment, in the first heating mode in which the refrigerant is decompressed by the fixed throttle 17, heat transfer between the refrigerant after passing through the fixed throttle 17 and the refrigerant inside the body 140 can be further suppressed. A decrease in ability can be further suppressed.

(Eighth embodiment)
In the present embodiment, a member having a high thermal resistance is added between the integrated valve 14 and the second joint 61 on the integrated valve side, as in the seventh embodiment, with respect to the fourth embodiment.

  As shown in FIG. 17, a member 71 g having a higher thermal resistance than the body 140 and the joint 71 is disposed between the body 140 of the integrated valve 14 and the joint 71 on the integrated valve side. This member 71g is disposed in a recess formed in a portion of the outer surface of the body 140 that faces the peripheral portion of the second refrigerant outlet 141e and the peripheral portion of the third refrigerant outlet 141i. This member 71g is the same as the member 61d of the seventh embodiment. For this reason, also in this embodiment, there exists an effect similar to 7th Embodiment.

(Ninth embodiment)
In the first to eighth embodiments, the gas-phase refrigerant passage 142b from the gas-liquid separation space 141b to the first refrigerant outlet 142a is opened and closed, and the liquid-phase refrigerant from the gas-liquid separation space 141b to the second refrigerant outlet 141e. As the valve body for opening and closing the passage 141d1, the two valve bodies of the liquid phase refrigerant side valve body 15 and the gas phase refrigerant side valve body 18 were used.

  On the other hand, in this embodiment, as shown in FIGS. 18 and 19, an integrated valve body 29 in which the functions of the two valve bodies are integrated into one is used. The integrated valve body 29 is the same as the integrated valve body 29 included in the integrated valve 14 described in Patent Document 2. In this embodiment, the integrated valve body 29 is applied to the integrated valve 14 of the first embodiment, but the integrated valve body 29 is also applied to the integrated valve 14 of the second to eighth embodiments. It can also be applied.

  The integrated valve 14 of the present embodiment has a liquid phase refrigerant passage 141d1 extending from the gas-liquid separation space 141b to the second refrigerant outlet 141e and a gas-liquid separation space 141b on the lowermost side of the gas-liquid separation space 141b of the body 140. A liquid-phase refrigerant passage 141d2 reaching the three refrigerant outlets 141i is formed. The liquid phase refrigerant passages 141d1 and 141d2 are refrigerant passages that guide the liquid phase refrigerant separated in the gas-liquid separation space 141b to the corresponding refrigerant outlets 141e and 141i.

  Specifically, a first outlet hole 141c1 and a second outlet hole serving as outlets of the liquid-phase refrigerant separated in the gas-liquid separation space 141b are respectively formed on the bottom surface and the side surface constituting the gas-liquid separation space 141b of the body 140. 141c2. The first outlet hole 141c1 is disposed directly below the separated gas-phase refrigerant outlet hole 142d in the bottom surface constituting the gas-liquid separation space 141b, and faces the separated gas-phase refrigerant outlet hole 142d. The 2nd exit hole 141c2 is arrange | positioned in the lowest part of the side surface which comprises the gas-liquid separation space 141b.

  The liquid-phase refrigerant passage 141d1 connected to the second refrigerant outlet 141e is connected to the first outlet hole 141c1. Further, the liquid-phase refrigerant passage 141d2 connected to the third refrigerant outlet 141i is connected to the second outlet hole 141c2.

  The integrated valve body 29 is accommodated in the gas-liquid separation space 141b of the body 140. The integrated valve element 29 is disposed between the first outlet hole 141c1 and the separated vapor phase refrigerant outlet hole 142d that face each other in the vertical direction. The integrated valve body 29 is moved up and down by the stepping motor 28, and closes one of the first outlet hole 141c1 and the separated vapor-phase refrigerant outlet hole 142d and opens the other. In this way, the integrated valve element 29 includes the liquid-phase refrigerant passage 141d1 extending from the gas-liquid separation space 141b to the second refrigerant outlet 141e, and the gas-phase refrigerant passage extending from the gas-liquid separation space 141b to the first refrigerant outlet 142a. 142b is alternatively opened and closed.

  In the present embodiment, the first and second outlet holes 141c1 and 141c2 are separated from each other on the surface of the body 140 constituting the gas-liquid separation space 141b. Thereby, when the integrated valve body 29 closes the liquid-phase refrigerant passage 141d1 connected to the second refrigerant outlet 141e, the liquid-phase refrigerant can flow out from the third refrigerant outlet 141i.

  Here, in the integrated valve element 29, a resin liquid phase refrigerant side seal member 29a formed in an annular shape on the lower surface side is disposed, and a resin gas phase refrigerant side seal member formed in an annular shape on the upper surface side. 29b is arranged. As shown in FIG. 18, when the integrated valve body 29 closes the liquid phase refrigerant passage 141d1 connected to the second refrigerant outlet 141e, the liquid phase refrigerant side seal member 29a is connected to the first outlet of the liquid phase refrigerant passage 141d1. It abuts on the hole 141c1. As shown in FIG. 19, the gas-phase refrigerant side seal member 29b contacts the separated gas-phase refrigerant outlet hole 142d of the separated gas-phase refrigerant outlet pipe portion 142c when the integrated valve body 29 closes the gas-phase refrigerant passage 142b. Touch.

  Further, the integrated valve body 29 is connected to a movable member of the stepping motor 28 fixed to the upper side of the body 140 by fastening means such as bolt fastening via a shaft 29c that functions as a drive mechanism. The shaft 29c is disposed coaxially with the separated gas-phase refrigerant outflow pipe portion 142c, and is disposed so as to penetrate the inside of the separated gas-phase refrigerant outflow pipe portion 142c.

  The stepping motor 28 is a driving means for displacing the integrated valve body 29 in the axial direction (vertical direction) of the shaft 29c, and its operation is controlled by a control pulse output from the air conditioning control device 40.

  In the present embodiment, a vapor phase refrigerant passage 142b is formed inside the separated vapor phase refrigerant outflow pipe portion 142c. A communication hole is provided on the upper end side of the separated gas-phase refrigerant outflow pipe portion 142c so as to communicate the upper end side of the separated gas-phase refrigerant outflow pipe portion 142c with the outside of the body 140. The opening on the side constitutes the first refrigerant outlet 142a. The communication hole extends in a direction perpendicular to the axial direction of the separated gas-phase refrigerant outflow pipe portion 142c.

  The body 140 includes an upper body 143 in which a gas-liquid separation space 141b is formed, and a lower body 144 in which a liquid-phase refrigerant passage 141d1 connected to the second refrigerant outlet 141e is formed.

  In the integrated valve 14 of the present embodiment, for example, in the first heating mode, as shown in FIG. 18, the integrated valve body 29 closes the liquid-phase refrigerant passage 141d1 connected to the second refrigerant outlet 141e, and the gas-phase refrigerant passage. 142b is opened. As a result, as in the first embodiment, the liquid refrigerant separated in the gas-liquid separation space 141b is transferred from the third refrigerant outlet 141i via the liquid refrigerant passage 141d2 connected to the third refrigerant outlet 141i. leak. The liquid-phase refrigerant that has flowed out of the third refrigerant outlet 141i is decompressed and expanded in an enthalpy manner until it becomes a low-pressure refrigerant in the fixed throttle 17, and flows into the outdoor heat exchanger 20.

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

  (1) In the first to eighth embodiments, the second and third refrigerant outlets 141e and 141i are provided on the bottom surface of the body 140. However, the second and third refrigerant outlets 141e and 141i are provided on the side surfaces of the body 140. It may be provided.

  (2) In each of the embodiments described above, the shape of the body 140 is a substantially cylindrical shape, but may be other shapes such as a prismatic shape.

  (3) In each of the above embodiments, the heat pump cycle of the present invention is applied to a vehicle air conditioner. However, the heat pump cycle may be applied to a stationary air conditioner, a cold storage container, a liquid heating device, and the like. When applied to a liquid heating device, the liquid heated by the liquid heating device is a heat exchange target fluid of the radiator.

  (4) The above embodiments are not irrelevant to each other, and can be combined as appropriate unless the combination is clearly impossible. In each of the above-described embodiments, it is needless to say that elements constituting the embodiment are not necessarily essential unless explicitly stated as essential and clearly considered essential in principle. Yes.

11 Compressor 13 High-stage expansion valve (pressure reduction means)
14 Integrated valve 140 Body 141a Refrigerant inlet 141b Gas-liquid separation space 142a First refrigerant outlet 141e Second refrigerant outlet 141i Third refrigerant outlet 141d1 Liquid-phase refrigerant passage connected to the second refrigerant outlet 141d2 Third refrigerant outlet 15 Liquid-phase refrigerant passage that continues to 15 Liquid-phase refrigerant-side valve element 17 Fixed throttle 18 Gas-phase refrigerant-side valve element 61 Second joint (piping parts) on the integrated valve side

Claims (3)

An intermediate pressure port (11b) that compresses the low-pressure refrigerant sucked from the suction port (11a) and discharges the high-pressure refrigerant from the discharge port (11c), and flows the intermediate-pressure refrigerant in the cycle into the refrigerant in the compression process. A compressor (11) having
A heat radiator (12) that heat-exchanges the high-pressure refrigerant by heat-exchanging the high-pressure refrigerant and heat exchange target fluid discharged from the discharge port, and heats the heat exchange target fluid;
Decompression means (13) for depressurizing the high-pressure refrigerant flowing out of the radiator until it becomes an intermediate-pressure refrigerant;
An integrated valve (14) having a function of separating the gas-liquid of the intermediate pressure refrigerant decompressed at least by the decompression means;
A fixed throttle (17) for reducing the intermediate-pressure liquid-phase refrigerant flowing out of the integrated valve to a low-pressure refrigerant;
An evaporator (20) that evaporates the low-pressure refrigerant flowing out of the fixed throttle and flows out to the suction port side,
The integrated valve includes a refrigerant inlet (141a) through which the intermediate-pressure refrigerant decompressed by the decompression means flows in, a gas-liquid separation space (141b) that separates the gas and liquid of the refrigerant flowing in from the refrigerant inlet, and the gas The first refrigerant outlet (142a) that causes the gas-phase refrigerant separated in the liquid separation space to flow out to the intermediate pressure port side, and the liquid-phase refrigerant separated in the gas-liquid separation space to flow out to the evaporator side. A body (140) in which a second refrigerant outlet (141e) and a third refrigerant outlet (141i) are formed;
Inside the body, a gas-phase refrigerant passage (142b) from the gas-liquid separation space to the first refrigerant outlet is opened and closed, and a liquid-phase refrigerant from the gas-liquid separation space to the second refrigerant outlet is provided. The valve body (15, 18, 29) for opening and closing the passage (141d1) is accommodated,
When the valve body closes the liquid-phase refrigerant passage from the gas-liquid separation space to the second refrigerant outlet, the body removes the liquid-phase refrigerant separated in the gas-liquid separation space. A liquid-phase refrigerant passage (141d2) that flows out from the outlet is formed,
Further, the piping parts (61, 62, 63) are arranged outside the body and formed as a separate body from the body and constitute a refrigerant passage from the third refrigerant outlet to the refrigerant inlet of the evaporator. 71) ,
The pipe parts include joints (51, 61, 71) directly connected to the second refrigerant outlet and the third refrigerant outlet of the body, and pipes (52, 62, 72) directly connected to the joint. )
The fixed throttle is provided in an internal passage (61b, 71b) of the joint (61, 71) through which the refrigerant flowing out from the third refrigerant outlet flows.
The heat pump cycle , wherein the joint has a recess (61c, 71f) that forms a gap with the outer surface of the body at a portion facing the outer surface of the body . An intermediate pressure port (11b) that compresses the low-pressure refrigerant sucked from the suction port (11a) and discharges the high-pressure refrigerant from the discharge port (11c), and flows the intermediate-pressure refrigerant in the cycle into the refrigerant in the compression process. A compressor (11) having
A heat radiator (12) that heat-exchanges the high-pressure refrigerant by heat-exchanging the high-pressure refrigerant and heat exchange target fluid discharged from the discharge port, and heats the heat exchange target fluid;
Decompression means (13) for depressurizing the high-pressure refrigerant flowing out of the radiator until it becomes an intermediate-pressure refrigerant;
An integrated valve (14) having a function of separating the gas-liquid of the intermediate pressure refrigerant decompressed at least by the decompression means;
A fixed throttle (17) for reducing the intermediate-pressure liquid-phase refrigerant flowing out of the integrated valve to a low-pressure refrigerant;
An evaporator (20) that evaporates the low-pressure refrigerant flowing out of the fixed throttle and flows out to the suction port side,
The integrated valve includes a refrigerant inlet (141a) through which the intermediate-pressure refrigerant decompressed by the decompression means flows in, a gas-liquid separation space (141b) that separates the gas and liquid of the refrigerant flowing in from the refrigerant inlet, and the gas The first refrigerant outlet (142a) that causes the gas-phase refrigerant separated in the liquid separation space to flow out to the intermediate pressure port side, and the liquid-phase refrigerant separated in the gas-liquid separation space to flow out to the evaporator side. A body (140) in which a second refrigerant outlet (141e) and a third refrigerant outlet (141i) are formed;
Inside the body, a gas-phase refrigerant passage (142b) from the gas-liquid separation space to the first refrigerant outlet is opened and closed, and a liquid-phase refrigerant from the gas-liquid separation space to the second refrigerant outlet is provided. The valve body (15, 18, 29) for opening and closing the passage (141d1) is accommodated,
When the valve body closes the liquid-phase refrigerant passage from the gas-liquid separation space to the second refrigerant outlet, the body removes the liquid-phase refrigerant separated in the gas-liquid separation space. A liquid-phase refrigerant passage (141d2) that flows out from the outlet is formed,
Further, the piping parts (61, 62, 63) are arranged outside the body and formed as a separate body from the body and constitute a refrigerant passage from the third refrigerant outlet to the refrigerant inlet of the evaporator. 71) ,
The pipe parts include joints (51, 61, 71) directly connected to the second refrigerant outlet and the third refrigerant outlet of the body, and pipes (52, 62, 72) directly connected to the joint. )
The fixed throttle is provided in an internal passage (61b, 71b) of the joint (61, 71) through which the refrigerant flowing out from the third refrigerant outlet flows.
A member (61d, 71g) having a higher thermal resistance than the body and the joint is disposed between the outer surface of the body and the joint . The joint (71) connects one pipe (72) to the second refrigerant outlet and the third refrigerant outlet, and is a portion directly connected to the second refrigerant outlet. The heat pump cycle according to claim 1 or 2, wherein the portion directly connected to the third refrigerant outlet is configured as an integral part.

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