JP2007071430A - Refrigeration cycle and compression auxiliary device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To save energy by reducing power of a compressor in a refrigeration cycle. <P>SOLUTION: In this refrigeration cycle, a turbine 21 is rotated by a refrigerant delivered from a gas cooler 2 to generate drive power to rotate a pump 22 in an accumulator 6, and the refrigerant introduced from an evaporator 4 is compressed by the pump 22. Thus the pressure of the refrigerant delivered toward by the compressor 1 by the rotation of the pump 22, that is, inlet pressure of the compressor 1 can be increased. As a result, the power of the compressor 1 can be reduced, and energy-saving can be achieved. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a refrigeration cycle applied to an air conditioner, and a compression assisting device constituting the refrigeration cycle.

Conventionally, chlorofluorocarbon has been used as a refrigerant in a refrigeration cycle such as an air conditioner for automobiles. However, since there is a problem of ozone layer destruction, in recent years, refrigeration using, for example, carbon dioxide (CO ₂ ) or the like as an alternative refrigerant. A cycle has been developed.

  However, in the refrigeration cycle using carbon dioxide or the like, the power required for the compressor is large because the refrigerant pressure on the high pressure side is equal to or higher than the critical pressure of the refrigerant. For this reason, if it is going to implement | achieve this with the conventional refrigerating cycle, a lot of energy will be needed.

  Thus, from the viewpoint of energy saving, an ejector cycle configured by using, for example, an ejector has been proposed as a technique for effectively using expansion energy that has been wasted in conventional expansion devices (see, for example, Patent Document 1).

  In this ejector cycle, a compressor, a radiator, an ejector, and a gas-liquid separator are connected in series, a gas outlet of the gas-liquid separator is connected to an inlet of the compressor, and a liquid of the gas-liquid separator is connected. The outlet is connected to the suction port of the ejector via an evaporator.

  The ejector is composed of a nozzle having a jet outlet at the tip, a mixing part formed in a cylindrical shape from the outer periphery to the downstream side of the jet outlet, and a diffuser formed so as to extend from the mixing part. The nozzle depressurizes the refrigerant cooled by the radiator to below the evaporating pressure and ejects it with a jet flow having a pressure lower than the tip, and sucks the gas refrigerant from the evaporator with a differential pressure generated by the depressurization. In the mixing section, the sucked gas refrigerant and the jet flow from the nozzle are mixed, and in the diffuser, the mixed refrigerant is decelerated and pressurized by increasing the area. That is, since the suction pressure of the compressor is increased by increasing the pressure of the refrigerant by the ejector, the power for compressing the compressor to a predetermined pressure can be reduced accordingly.

However, since such an ejector has a very complicated shape connected to the nozzle, the mixing portion, and the diffuser, there is a problem that the processing is difficult and the manufacturing cost increases.
On the other hand, a refrigeration cycle in which an auxiliary compressor that efficiently transmits power obtained on the expansion side to the compressor side on the upstream side of the compressor has also been proposed (see, for example, Patent Document 2).

This auxiliary compressor shares a housing and a main shaft with the expander, and is partitioned from the expander by a swash plate disposed in the housing and a piston connected thereto. A rotary valve is provided at the end of the main shaft on the expander side, and the high-pressure refrigerant from the radiator is introduced into the expansion chamber through the rotary valve, and the low-pressure refrigerant that has been expanded there passes through the rotary valve. Derived to the evaporator side. A rotational force is applied to the main shaft by the recovery power of the expander due to the introduction and extraction of the refrigerant, and the reciprocating operation of the piston compresses the refrigerant on the auxiliary compressor side and expands the refrigerant on the expander side. Thus, the suction pressure of the main compressor is increased by increasing the pressure of the refrigerant in the auxiliary compressor, so that the power for compressing the main compressor to a predetermined pressure can be reduced accordingly.
Japanese Patent No. 3322263 (paragraphs [0091] to [0096]) JP 2000-46429 A (paragraphs [0038], [0039])

  However, in the refrigeration cycle described in Patent Document 2, since the rotational power of the main shaft is generated by the refrigerant introduced from the radiator, the inside of the housing must be kept airtight so as not to leak the refrigerant. Therefore, there is a problem that the seal must be provided over the entire outer periphery of the housing, and the cost is increased rather than the above-described ejector.

  This invention is made | formed in view of such a point, and it aims at providing the refrigerating cycle which can implement | achieve at low cost and can aim at energy saving by reducing the motive power of a compressor.

  In the present invention, in order to solve the above problems, in a refrigeration cycle constituting an air conditioner, a compressor that compresses a refrigerant, a radiator that cools the refrigerant discharged from the compressor, and an introduced refrigerant are gas-liquid An accumulator that separates and stores the gas refrigerant toward the compressor, an expansion device that expands and decompresses the liquid refrigerant stored in the accumulator, and a refrigerant that is decompressed by the expansion device An evaporator for evaporating the liquid, a turbine disposed in the accumulator, rotated by a refrigerant introduced from the radiator and discharging the refrigerant into the accumulator, and rotated with the turbine and introduced from the evaporator A turbine pump having a pump for compressing the generated refrigerant and releasing the refrigerant into the accumulator. Cycle is provided.

  In such a refrigeration cycle, since the turbine pump is arranged in an accumulator normally used in the system, it is not necessary to provide a special seal for preventing external leakage of the refrigerant, and it can be realized at low cost. Can do.

  And the driving force which rotates a turbine with the refrigerant | coolant introduced from the heat radiator and rotates a pump is generated, and the refrigerant | coolant introduced from the evaporator is compressed with the pump. For this reason, the pressure of the refrigerant sent to the compressor by the rotation of the pump, that is, the suction pressure of the compressor can be increased. As a result, the power of the compressor can be reduced to save energy.

  In the present invention, the compressor that compresses the refrigerant, the radiator that cools the refrigerant discharged from the compressor, and the introduced refrigerant are stored in a gas-liquid separated state, and the gas refrigerant is stored in the compressor. Used in a refrigeration cycle comprising: an accumulator that is sent out toward the air, an expansion device that squeezes and expands the liquid refrigerant stored in the accumulator, and an evaporator that evaporates the refrigerant decompressed by the expansion device A turbine which is a compression assisting device and is configured by integrally assembling the accumulator and the expansion device, and is rotated by a refrigerant introduced from the radiator inside the accumulator and releases the refrigerant into the accumulator. And a pump that rotates with the turbine and compresses the refrigerant introduced from the evaporator and discharges the refrigerant into the accumulator. The turbine pump is provided that, the compression aid is provided, wherein.

  In such a compression assisting device, since the turbine pump is disposed in the accumulator, it is not necessary to provide a special seal for preventing external leakage of the refrigerant, and can be realized at low cost. Further, since the expansion device is integrally assembled, the number of pipes is reduced when applied to the refrigeration cycle, and the space can be saved.

  Furthermore, when applied to a refrigeration cycle, a driving force for rotating the turbine is generated by the refrigerant introduced from the radiator to rotate the pump, and the refrigerant introduced from the evaporator is compressed by the pump. For this reason, the suction pressure of the compressor can be increased, and the power of the compressor can be reduced to save energy.

  According to the refrigeration cycle of the present invention, since the turbine pump for increasing the suction pressure of the compressor is provided inside the accumulator, it can be realized at low cost, and the power of the compressor can be reduced to save energy. it can.

  Further, according to the compression assisting device of the present invention, since the turbine pump for increasing the suction pressure of the compressor is provided inside the accumulator, when applied to the refrigeration cycle, this can be realized at low cost. It is possible to reduce energy and save energy.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[First Embodiment]
In this embodiment, the refrigeration cycle of the present invention is applied to an automotive air conditioner, and is configured as a supercritical refrigeration cycle using carbon dioxide as a refrigerant. FIG. 1 is a system configuration diagram showing a refrigeration cycle according to the first embodiment.

  The refrigeration cycle of the present embodiment is driven by an automobile engine to compress the refrigerant to a supercritical region, and a gas cooler 2 (cooling device) that cools the refrigerant discharged from the compressor 1. The auxiliary refrigerant 3 that increases the pressure of the refrigerant led to the compressor 1 and evaporates the liquid refrigerant decompressed by the auxiliary compressor 3 to cool the passenger compartment. The evaporator 4 is provided.

  The compressor 1 is a swash plate type variable capacity compressor capable of controlling the discharge capacity of the refrigerant to be constant regardless of the rotational speed of the engine. The compressor 1 incorporates a solenoid-controlled capacity control valve 5 that can be electronically controlled, and the capacity control valve 5 controls the discharge capacity. This capacity control valve 5 controls the capacity so as to maintain the differential pressure between the discharge pressure Pd and the suction pressure Ps of the compressor 1 at a predetermined differential pressure determined by an external signal supplied to the solenoid. Control valve. The capacity control valve 5 receives the discharge pressure Pd and the suction pressure Ps of the compressor 1 and controls the flow rate of supplying the refrigerant having the discharge pressure Pd discharged from the compressor 1 to the crank chamber of the compressor 1. Accordingly, the refrigerant discharge capacity is controlled to be constant by controlling the pressure Pc of the crank chamber to a pressure corresponding to the discharge capacity. As this capacity control valve 5, for example, an electromagnetic control valve described in JP-A-2001-132650 can be used.

  The compression assisting device 3 has a flow rate control valve 7 for adjusting the flow rate of the refrigerant introduced from the gas cooler 2 and a liquid refrigerant to expand and depressurize the accumulator 6 that separates and stores the introduced refrigerant by gas-liquid separation. The expansion device 8 is assembled integrally. In the accumulator 6, a turbine pump 9 is arranged to compress the introduced refrigerant and increase its pressure.

Next, the configuration of the compression auxiliary device will be described in detail. FIG. 2 is a cross-sectional view illustrating the configuration of the compression assisting device.
The accumulator 6 that constitutes the compression assisting device 3 has a gas phase part 11 and a liquid phase part 12 at the top and bottom, a tank 13 that accommodates the refrigerant in a gas-liquid separated state, and a gas phase that penetrates the tank 13 in and out. It is comprised from the refrigerant | coolant piping 14 which guides the gas refrigerant of the part 11 to the compressor 1. FIG. One end of the refrigerant pipe 14 opens into the gas phase portion 11, and the other end is connected to the compressor 1 side. In the pipe wall passing through the liquid phase portion 12 of the refrigerant pipe 14, a communication hole 15 (“throttle” for deriving a predetermined amount of the liquid refrigerant in the liquid phase portion 12 into the pipe and mixing with the gas refrigerant derived from the gas phase portion 11. Corresponding to “flow path”) is provided. Thus, by deriving the liquid refrigerant in the liquid phase portion 12, the lubricating oil mixed in the liquid phase portion 12 is returned to the compressor 1 side, and the lubrication in the compressor 1 is maintained.

  The turbine pump 9 is fixed to the upper part of the gas phase part 11 in the tank 13. The turbine pump 9 includes a turbine 21 that is rotated by the refrigerant introduced from the gas cooler 2, and a rotary pump 22 that rotates together with the turbine 21 and compresses the refrigerant introduced from the evaporator 4. The turbine 21 and the pump 22 have a common body 23 and a rotating shaft 24. The inside of the turbine 21 is connected to the gas cooler 2 via the flow control valve 7, and the flow rate of the introduced refrigerant is adjusted by the flow control valve 7. On the other hand, the inside of the pump 22 is connected to the evaporator 4 via a pipe forming member 25. One end of the pipe forming member 25 is connected to a pipe (not shown) that penetrates the side wall of the tank 13 and is connected to the evaporator 4. The detailed configuration and operation of the turbine pump 9 will be described later.

  The flow control valve 7 is fixed to the upper part of the tank 13. The flow rate control valve 7 is configured to drive a valve portion 32 that is assembled in the body 31, a valve portion 32 that is accommodated in the body 31 and opens and closes the refrigerant passage, and a valve portion 32 that opens and closes the refrigerant passage. And a solenoid 33. The flow control valve 7 is connected to the turbine 21 via a valve seat forming member 34. The detailed configuration and operation of the flow control valve 7 will be described later.

  The expansion device 8 includes a long body 41 that vertically penetrates the inside and outside of the tank 13, a valve portion 42 that controls the flow rate of the liquid refrigerant supplied from the liquid phase portion 12 to the evaporator 4, and the pipe forming member 25. And a temperature-sensitive actuator 43 in which a load for urging the valve part 42 in the valve opening direction changes according to the temperature of the refrigerant entering the pump 22, and a valve part arranged on the low-pressure side of the valve part 42. And a temperature-sensitive actuator 44 that changes the load that urges the valve portion 42 in the valve closing direction in accordance with the temperature of the liquid refrigerant that has passed through the valve 42. The detailed configuration and operation of the expansion device 8 will be described later.

FIG. 3 is a cross-sectional view showing the configuration of the turbine pump. 4 is a cross-sectional view taken along line AA in FIG. 5 is a cross-sectional view taken along the line BB in FIG.
As shown in FIG. 3, the turbine pump 9 has a cylindrical body 23 made of a resin such as PPS (Polyphenylene Sulfide). The body 23 has an inner diameter formed in two stages in the axial direction, and the small diameter side constitutes a pressure chamber 26 of the turbine 21, and the large diameter side constitutes a pressure chamber 27 of the pump 22.

  A cylindrical sleeve 51 made of stainless steel is fitted into the pressure chamber 26 on the turbine 21 side along the inner peripheral surface thereof. A counterbore is formed at the opening end of the pressure chamber 26 of the body 23, and a disc-shaped bearing member 52 made of stainless steel seals the pressure chamber 26 while being locked to the counterbore. It is press-fitted in various ways. A boss-like bearing portion 53 is provided at an eccentric position of the bearing member 52 so as to protrude outward.

  On the other hand, a cylindrical sleeve 54 made of stainless steel is fitted in the pressure chamber 27 on the pump 22 side along the inner peripheral surface thereof. Also, a counterbore is formed at the opening end of the pressure chamber 27 of the body 23, and a disk-shaped bearing member 55 made of stainless steel seals the pressure chamber 27 while being locked to the counterbore. It is press-fitted in various ways. A boss-like bearing portion 56 is provided at an eccentric position of the bearing member 55 facing the bearing portion 53 so as to protrude outward.

  One end of the rotary shaft 24 is rotatably supported by the bearing portion 53 and the other end is rotatably supported by the bearing portion 56. Then, the rotor 57 of the turbine 21 and the rotor 58 of the pump 22 are fitted to each other with the substantial center as a boundary. The rotor 57 is provided with three vanes 59 constituting the blades of the turbine 21 at equal intervals. The rotor 58 is provided with three vanes 60 constituting the blades of the pump 22 at equal intervals. Yes. A partition plate 61 made of stainless steel that partitions the turbine 21 and the pump 22 is disposed at the center in the axial direction of the body 23. The rotating shaft 24 passes through a circular hole 62 provided in the partition plate 61.

  Further, the rotation shaft 24 is formed with a refrigerant outlet passage 63 penetrating in the axial direction, and communicates with the refrigerant outlet passage 63 at a position corresponding to the circular hole 62 at the center of the axial direction in the radial direction. A refrigerant leakage path 64 penetrating through is formed. On the other hand, refrigerant outlets 65 and 66 are formed at positions facing the refrigerant outlet passage 63 of the bearing portions 53 and 56, respectively. For this reason, even if the refrigerant in the pressure chamber 26 of the turbine 21 leaks into the gap between the rotor 57 and the partition plate 61, the refrigerant is the refrigerant leakage path 64, the refrigerant outlet path 63, and the refrigerant outlets 65 and 66. To the outside of the turbine pump 9, that is, to the gas phase portion 11 in the accumulator 6. For this reason, it is possible to prevent the refrigerant from entering the low-pressure pump 22 and causing malfunction.

  As shown in FIG. 4, the turbine 21 has a refrigerant introduction path 71 that penetrates the body 23 from the pressure chamber 26 in the radial direction. On the other hand, the refrigerant introduction path 71 is connected to the flow rate control valve 7 via the valve seat forming member 34 (see FIG. 2). The sleeve 51 is configured by elastically deforming a belt-shaped stainless steel plate into a circular shape, and hook portions 72 provided at both ends thereof are hooked and fixed to the base end portion of the refrigerant introduction path 71. Therefore, the sleeve 51 is disposed so as to abut against the inner wall surface of the pressure chamber 26 by its elastic return force.

  The rotating shaft 24 is in a position eccentric with respect to the axis of the pressure chamber 26, and rotating shafts 73 of vanes 59 are provided at three locations around the rotor 57. The vane 59 is configured to bend and extend from the rotation shaft 73 in the direction opposite to the rotation direction thereof. Between the vane 59 and the rotating shaft 73, a torsion spring that biases the vane 59 in a direction in which the vane 59 is separated from the rotor 57 is provided. Therefore, the outer peripheral surface of the vane 59 comes into contact with the sleeve 51 with a predetermined pressure, and a predetermined pressure space is formed by the adjacent vane 59 and the sleeve 51. Since the rotating shaft 24 is eccentric, the size of the pressure space changes with rotation.

  Further, a crescent-shaped lead-out hole 74 is formed at a position facing the pressure chamber 26 of the bearing member 52, and the refrigerant introduced from the refrigerant introduction path 71 is externally provided, that is, in the gas phase portion 11 of the accumulator 6. It can be derived.

  As shown in FIG. 5, the pump 22 has a refrigerant outlet path 81 that penetrates the body 23 from the pressure chamber 27 in the radial direction. On the other hand, the refrigerant outlet path 81 communicates with the outside, that is, the gas phase portion 11 of the accumulator 6 (see FIG. 2). A check valve 82 made of a leaf spring is provided in a cantilevered state in the vicinity of the opening end on the outside of the refrigerant outlet path 81. Therefore, the refrigerant is prevented from flowing back and entering the pump 22 from the refrigerant outlet path 81, and when the pressure in the vicinity of the refrigerant outlet path 81 of the pump 22 exceeds a predetermined value, the check valve 82 is opened. The refrigerant can be derived. The pressure chamber 27 has a volume about three times that of the pressure chamber 26 of the turbine 21.

  The sleeve 54 is configured by elastically deforming a belt-shaped stainless steel plate into a circular shape, and hook portions 83 provided at both ends thereof are hooked and fixed to the base end portion of the refrigerant outlet path 81. Therefore, the sleeve 54 is disposed so as to abut on the inner wall surface of the pressure chamber 27 by its elastic restoring force.

  The rotating shaft 24 is in an eccentric position with respect to the axis of the pressure chamber 27, and the rotating shaft 84 of the vane 60 is provided at three locations around the rotor 58. The vane 60 is configured to bend and extend in the rotational direction from the rotation shaft 84. Between the vane 60 and the rotating shaft 84, a torsion spring (not shown) that urges the vane 60 in a direction in which the vane 60 is separated from the rotor 58 is provided. Therefore, the outer peripheral surface of the vane 60 comes into contact with the sleeve 54 at a predetermined pressure, and a predetermined pressure space is formed by the adjacent vane 60 and the sleeve 54. Since the rotating shaft 24 is eccentric, the size of the pressure space changes with rotation.

  Further, a crescent-shaped introduction hole 85 is formed at a position facing the inside of the pressure chamber 27 of the bearing member 55. The introduction hole 85 communicates with the inside of the pipe forming member 25 so that the refrigerant led out from the evaporator 4 can be introduced into the pump 22.

  Next, the operation of the turbine pump will be described. FIG. 6 is a cross-sectional view illustrating the operation of the turbine. (A)-(D) represent the state which the rotor of the turbine rotated 30 degrees at a time in the counterclockwise direction of a figure. FIG. 7 is a cross-sectional view showing the operation of the pump. FIGS. 6A to 6D show states in which the rotor of the pump is sequentially rotated by 30 degrees clockwise in the drawing, and corresponds to FIGS. 6A to 6D, respectively.

  As shown in FIGS. 6A and 6B, the high-pressure refrigerant introduced into the turbine 21 from the gas cooler 2 side via the refrigerant introduction path 71 is introduced into the pressure space S1 formed between the adjacent vanes 59. Is done. At this time, the pressure in the other pressure spaces S <b> 2 and S <b> 3 is reduced by the refrigerant being led out from the outlet hole 74. For this reason, a front-back differential pressure is generated in the vane 59 in the front in the rotational direction, and a rotational force of the rotor 57 is generated. This rotational force is transmitted to the rotor 58 of the pump 22 through the rotating shaft 24, and the pump 22 is rotationally driven.

  Then, as shown in FIG. 6C, after the rotor 57 further rotates and the pressure space S1 is sealed, the pressure space S1 communicates with the outlet hole 74 as shown in FIG. Thus, the internal refrigerant is discharged to the gas phase portion 11.

  On the other hand, as shown in FIG. 7A, the low-pressure refrigerant sucked by the negative pressure accompanying the rotation of the pump 22 and introduced into the pump 22 from the evaporator 4 side through the introduction hole 85 is adjacent to the vane 60. It is introduced into a pressure space S11 formed therebetween. Then, as shown in FIG. 5B, when the rotor 58 further rotates in a state where the pressure space S11 is in a sealed state, the pressure space S11 gradually decreases, so the internal refrigerant is compressed and the pressure is reduced. Enhanced. On the other hand, since the other pressure spaces S12 and S13 gradually increase, a negative pressure state occurs, and the refrigerant from the evaporator 4 is sucked into the inside through the introduction hole 85.

  When the pressure in the pressure space S11 exceeds a predetermined value, the check valve 82 is opened as shown in FIGS. 2C and 2D, so that the refrigerant whose pressure has been increased is released to the gas phase portion 11. . This refrigerant is sent to the compressor 1 through the refrigerant pipe 14 together with the saturated refrigerant in the gas phase section 11 (see FIG. 2).

Next, the configuration and operation of the flow control valve 7 will be described in detail. FIG. 8 is a cross-sectional view showing the configuration of the flow control valve 7.
The flow control valve 7 is configured as an on / off type electromagnetic valve, and includes a cylindrical body 31 that also serves as a pipe, a valve body 91 disposed inside the body 31, and a solenoid that drives and controls the valve body 91. 33. The valve portion 32 is configured by the valve body 91 and the above-described valve seat forming member 34.

  The valve seat forming member 34 has a valve hole 92 in the center of the disc-shaped main body, and a valve seat 93 protruding in a boss shape is provided at the opening edge of the valve hole 92 on the body 31 side. The body 31 is connected in a state where one end thereof is in contact with the valve seat forming member 34.

  The solenoid 33 includes a plunger 94 formed integrally with the valve body 91, a core 95 coaxially disposed on the upstream side of the plunger 94 and fixed to the body 31, and the plunger 94 and the core by a supply current from the outside. The electromagnetic coil 96 which produces | generates the magnetic circuit containing 95, and the cylindrical yoke 97 which is arrange | positioned so that this electromagnetic coil 96 may be covered, and comprises the case of the solenoid 33 are provided.

  The valve body 91, the plunger 94, and the core 95 are provided with a refrigerant passage through which the refrigerant that has flowed from the gas cooler 2 side is guided to the downstream side. The valve body 91 has a flat portion 98 that can be seated on the valve seat 93 and close the valve hole 92 at the tip thereof, and an opening 99 for leading out the refrigerant is formed in a side portion near the tip. ing. A spring 100 that biases the plunger in the valve closing direction is interposed between the plunger 94 and the core 95.

  In the above configuration, the magnetic circuit of the solenoid 33 surrounding the electromagnetic coil 96 is configured by the plunger 94, the core 95, the yoke 97, the body 31, and the like. Then, energization control to the electromagnetic coil 96 is performed by a control device (not shown).

  That is, when the electromagnetic coil 96 is not energized and the solenoid 33 is not driven, the valve body 91 is seated on the valve seat 93 by the biasing force of the spring 100. For this reason, the valve part 32 will be in a valve closing state. On the other hand, when the electromagnetic coil 96 is energized and the solenoid 33 is driven, the plunger 94 is attracted toward the core 95, the valve body 91 is lifted from the valve seat 93, and the valve portion 32 is opened. Here, the energization control is performed by duty control by on / off. For this reason, the flow rate of the refrigerant introduced from the gas cooler 2 to the turbine 21 is adjusted by changing the duty ratio.

Next, the configuration and operation of the expansion device 8 will be described in detail. FIG. 9 is a cross-sectional view illustrating the configuration of the expansion device 8.
The expansion device 8 includes the long cylindrical body 41. A refrigerant inlet 101 for introducing the refrigerant of the liquid phase portion 12 of the accumulator 6 is provided on the side portion near the lower end of the body 41, and a valve hole 102 is provided in the axial direction so as to communicate with the refrigerant inlet 101. . A valve body 103 that opens and closes the valve hole 102 is disposed downstream of the valve hole 102 so as to advance and retract in the axial direction. The valve hole 102 and the valve body 103 constitute a valve portion 42.

  The valve body 103 is integrally formed with a shaft 104 that extends through the valve hole 102 in the axial direction. The shaft 104 has an outer diameter smaller than the inner diameter of the valve hole 102, and when the liquid refrigerant is introduced into the refrigerant inlet 101, the valve 104 receives the force in the valve opening direction received by the valve body 103 in the valve closing direction. I try to be bigger than power.

  A spring receiving member 105 is fitted in the vicinity of the tip of the shaft 104, and a spring receiving member 106 is press-fitted into the open end of the enlarged diameter portion formed in the upper portion of the body 41. Between these spring receiving members 105 and 106, a coil-shaped shape memory alloy spring 107 and a biasing spring 108 are inserted in parallel.

  The shape memory alloy spring 107 has a bi-directional shape memory effect that reversibly changes with respect to the temperature cycle. When the temperature is lower than the transformation point, the spring load is small, and when the temperature is higher than the transformation point, the spring load is reduced. Has a characteristic of increasing in proportion to the temperature change. Therefore, the shape memory alloy spring 107 functions as a temperature-sensitive actuator in which the load that biases the valve body 103 in the valve opening direction changes according to the temperature of the refrigerant that leaves the evaporator 4 and enters the pump 22.

  The biasing spring 108 is for adjusting the spring characteristics of the shape memory alloy spring 107 and for adjusting the valve characteristics of the expansion device 8. The spring receiving member 106 is connected to the opening end of the body 41. Fine adjustment can be made by changing the amount of press-fitting into.

  A spring receiving member 109 is press-fitted into the open end of the enlarged diameter portion formed in the lower portion of the body 41. A coil-shaped shape memory alloy spring 110 is interposed between the spring receiving member 109 and the valve body 103, and a coil-shaped bias bias is interposed between the valve body 103 and the peripheral portion of the valve hole 102. A spring 111 is inserted.

The shape memory alloy spring 110 functions as a temperature-sensitive actuator in which the load that biases the valve body 103 in the valve closing direction changes according to the temperature of the refrigerant that is squeezed and expanded by the valve portion.
The bias spring 111 is for adjusting the spring characteristics of the shape memory alloy spring 110 and further the valve characteristics of the expansion device 8. The spring receiving member 109 is press-fitted into the lower opening end of the body 41. Fine adjustment is possible by changing the amount of press-fitting. The lower open end of the body 41 is fixed to the tank 13 in a state of being inserted into the end of the pipe 120 connected to the evaporator 4.

  In the expansion device 8 having the above configuration, when the temperature of the refrigerant sucked into the pump 22 from the evaporator 4 is within a predetermined temperature range equal to or higher than the transformation point of the shape memory alloy spring 107, the shape memory alloy spring 107 is The phase is transformed from the site phase to the austenite phase (parent phase), and the spring load changes substantially proportionally to the temperature change of the refrigerant.

  Similarly, in the shape memory alloy spring 110 that senses the temperature of the refrigerant on the low pressure side of the expansion device 8, the temperature of the refrigerant that has been squeezed and expanded by the valve portion is within a predetermined temperature range that is equal to or higher than the transformation point of the shape memory alloy spring 110. In this case, the spring load changes substantially in proportion to the temperature change of the refrigerant.

  Therefore, in this expansion device 8, the set load of the differential pressure that is opened by the pressure of the refrigerant due to the difference in effective diameter between the valve body 103 and the shaft 104 depends on the temperature sensed by the shape memory alloy spring 107 and the shape memory alloy spring 110. It is controlled by the temperature difference from the sensed temperature. In addition, when the shape memory alloy springs 107 and 110 reach a high temperature exceeding their predetermined temperature range, the rate of increase of their spring load rapidly decreases and becomes saturated, and the temperature further increases. However, the spring load will not increase. In addition, since the shape memory alloy springs 107 and 110 have a bidirectional shape memory effect, when the temperature of the refrigerant falls and falls below those transformation points, the phase transformation occurs and the spring load becomes small. .

  Next, the operation and effect of the refrigeration cycle of the present embodiment will be described. FIG. 10 is a Mollier diagram showing characteristics of the refrigeration cycle. In the figure, the horizontal axis represents enthalpy and the vertical axis represents pressure, and the refrigerant states at the positions indicated by reference signs a to i on the circuit of the refrigeration cycle of FIG. 1 are indicated by the same reference signs a to i.

  First, when the automotive air conditioner is activated and the compressor 1 is rotationally driven by the engine, the compressor 1 sucks and compresses the gas refrigerant from the accumulator 6 of the compression auxiliary device 3 and discharges it to the gas cooler 2 ( i → a). At this time, the compressor 1 has a capacity so that the differential pressure (Pd−Ps) between the discharge pressure Pd and the suction pressure Ps becomes a predetermined differential pressure determined by a control signal from a control device (not shown). Be controlled. The gas refrigerant is cooled by the gas cooler 2 (a → b).

  The flow rate of the refrigerant derived from the gas cooler 2 is adjusted by the flow rate control valve 7 and introduced into the turbine 21 in the accumulator 6 (b → c). Since the flow control valve 7 is a so-called on / off valve, there is almost no pressure loss. As a result, the turbine pump 9 is driven, and the pump 22 rotates to perform the refrigerant compression operation. The refrigerant introduced into the turbine 21 is decompressed in the expansion stroke of the turbine 21 and discharged to the gas phase part 11 of the accumulator 6 (c → d).

  In the accumulator 6, gas-liquid separation is performed (d → e), and the liquid refrigerant accumulated in the liquid phase portion 12 is expanded and decompressed by the expansion device 8 and is sent to the evaporator 4 (e → f). The liquid refrigerant passing through the evaporator 4 is heat-exchanged with the air blown into the passenger compartment, and is evaporated by heat absorption from the air (f → g).

  The refrigerant that has passed through the evaporator 4 is sucked by the pump 22 and compressed in the compression stroke to increase the pressure (g → h). The refrigerant whose pressure is increased and becomes superheated steam is discharged to the gas phase portion 11 and introduced into the refrigerant pipe 14 together with the saturated vapor, and is mixed with the liquid refrigerant led out from the communication hole 15 to be compressed. (H → i).

  As described above, according to the refrigeration cycle of the present embodiment, the accumulator 6 generates the driving force for rotating the turbine 21 by the refrigerant delivered from the gas cooler 2 to rotate the pump 22, and the evaporator 4. The refrigerant introduced from is compressed by the pump 22. For this reason, the pressure of the refrigerant sent to the compressor 1 by the rotation of the pump 22, that is, the suction pressure of the compressor 1 can be increased. As a result, the power of the compressor 1 can be reduced to save energy.

  In addition, since the turbine pump 9 is disposed in the accumulator 6 that is normally used in such a refrigeration cycle, it is not necessary to provide a special seal for preventing external leakage of the refrigerant, and can be realized at low cost. it can.

Further, since the compression auxiliary device 3 is configured by integrating the flow control valve 7 and the expansion device 8 with the accumulator 6, there is an advantage that the installation in the system is greatly simplified.
[Second Embodiment]
Next, a second embodiment of the present invention will be described. Since the refrigeration cycle according to the present embodiment is the same as the configuration of the first embodiment except that the configuration of the compression assisting device is different, the components that are substantially the same as the configuration of the first embodiment are the same. A description thereof will be omitted as appropriate. FIG. 11 is a cross-sectional view illustrating a configuration of a compression assisting device according to the second embodiment.

  In the compression assisting device 203 of this embodiment, a turbine pump 209 is disposed in the liquid phase portion 12 of the accumulator 206. The refrigerant pipe 14 passes vertically through the bottom of the tank 213 so as to be juxtaposed with the turbine pump 209, and its open end is positioned above the gas phase part 11.

  The turbine pump 209 has substantially the same configuration as the turbine pump 9 of the first embodiment, but a refrigerant outlet path 81 connected to the pump 22 extends from the body 223 and is in the liquid phase portion 12. It is directly connected to 14 tube wall portions. For this reason, the refrigerant that has been compressed by the pump 22 and becomes superheated steam can easily warm the mixed refrigerant in the refrigerant pipe 14.

  As a result, as shown in FIG. 10, the points i and a can be shifted to the high temperature side, that is, the side where the enthalpy becomes higher. Thereby, the coefficient of performance of the refrigeration cycle can be improved.

  Further, as shown in FIG. 11, since the turbine pump 209 is disposed below the accumulator 206, the position of the temperature-sensitive actuator 43 on the upper side of the expansion device 208 is lowered. For this reason, the length in the axial direction of the body 241 of the expansion device 208 is configured to be small.

  As described above, also in the refrigeration cycle of the present embodiment, the turbine pump 209 is disposed in the accumulator 206, and the driving force for rotating the turbine 21 by the refrigerant delivered from the gas cooler 2 and rotating the pump 22 is achieved. The refrigerant introduced from the evaporator 4 is compressed by the pump 22. For this reason, the suction pressure of the compressor 1 can be increased, and the power of the compressor 1 can be reduced to save energy. Further, it is not necessary to provide a special seal for the turbine pump 209, and the cost can be reduced.

  Further, since the turbine pump 209 is disposed in the liquid phase portion 12 of the accumulator 206, the lubricating oil dissolved in the liquid phase portion 12 can be used for lubricating the turbine 21 and the pump 22. For this reason, the operability of the turbine pump 209 is good, and the maintenance interval can be lengthened.

  In addition, the refrigerant lead-out path 281 of the pump 22 is directly connected to the pipe wall of the refrigerant pipe 14 so that the refrigerant that has been compressed by the pump 22 and becomes superheated steam is introduced into the refrigerant pipe 14 almost 100%. For this reason, the temperature of the refrigerant | coolant which flows through the refrigerant | coolant piping 14 can be raised rather than the case of 1st Embodiment, and the coefficient of performance of a refrigerating cycle can be improved, As a result, the efficiency of a system can be improved.

Furthermore, since the body 241 of the expansion device 208 can be made small, the cost can be reduced accordingly.
The preferred embodiment of the present invention has been described above, but the present invention is not limited to the specific embodiment, and it can be changed and modified within the spirit of the present invention. Not too long.

  For example, in each of the above embodiments, a rotary type pump is used as a pump constituting the turbine pump. However, a scroll type pump or a swash plate type that compresses by reciprocating the piston may be used.

  Further, in each embodiment, the flow control valve 7 is configured as an on / off valve by duty control of the solenoid 33. However, as a proportional valve or the like that can obtain a valve opening almost proportional to the current value supplied to the solenoid 33. It may be configured. Alternatively, the flow control valve 7 may be configured such that the valve portion is controlled to open and close by, for example, a stepping motor, or a so-called mechanical type in which the valve body is driven by an internal mechanical configuration including a spring and the refrigerant pressure. You may comprise as a control valve.

  In each embodiment, the refrigeration cycle of the present invention is configured as a supercritical refrigeration cycle in which carbon dioxide is used as a refrigerant and the refrigerant pressure after being compressed by the compressor 1 is equal to or higher than the critical pressure of the refrigerant. Although shown, it is good also as a supercritical refrigerating cycle using refrigerants other than a carbon dioxide. Further, instead of the supercritical refrigeration cycle, it is possible to configure the refrigerant pressure to be lower than the critical pressure of the refrigerant after the refrigerant is compressed by the compressor 1 using chlorofluorocarbon or the like as the refrigerant. In that case, a condenser is used as a radiator.

It is a system configuration figure showing the refrigerating cycle concerning a 1st embodiment. It is sectional drawing showing the structure of a compression assistance apparatus. It is sectional drawing showing the structure of a turbine pump. It is AA arrow sectional drawing of FIG. It is a BB arrow sectional view of Drawing 3. It is sectional drawing showing operation | movement of a turbine. It is sectional drawing showing operation | movement of a pump. 3 is a cross-sectional view illustrating a configuration of a flow control valve 7. FIG. 3 is a cross-sectional view illustrating a configuration of an expansion device 8. FIG. It is a Mollier diagram showing the characteristic of a refrigerating cycle. It is sectional drawing showing the structure of the compression assistance apparatus which concerns on 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Compressor 2 Gas cooler 3,203 Compression auxiliary device 4 Evaporator 5 Capacity control valve 6,206 Accumulator 7 Flow control valve 8,208 Expansion device 9,209 Turbine pump 11 Gas phase part 12 Liquid phase part 14 Refrigerant piping 15 Communication Hole 21 Turbine 22 Pump 43, 44 Temperature sensitive actuator 57, 58 Rotor 59, 60 Vane 71 Refrigerant introduction path 74 Outlet hole 81 Refrigerant outlet path 82 Check valve 85 Introduction hole

Claims (17)

In the refrigeration cycle constituting the air conditioner,
A compressor for compressing the refrigerant;
A radiator for cooling the refrigerant discharged from the compressor;
An accumulator that separates and stores the introduced refrigerant by gas-liquid separation, and sends the gas refrigerant toward the compressor;
An expansion device that squeezes and expands the liquid refrigerant stored in the accumulator;
An evaporator for evaporating the refrigerant decompressed by the expansion device;
A turbine disposed in the accumulator, rotated by the refrigerant introduced from the radiator and releasing the refrigerant into the accumulator, and rotated together with the turbine to compress the refrigerant introduced from the evaporator A turbine pump having a pump for discharging the refrigerant into the accumulator;
A refrigeration cycle comprising:   The refrigeration cycle according to claim 1, wherein the turbine pump is disposed in a gas phase portion of the accumulator.   The refrigeration cycle according to claim 1, wherein the turbine pump is disposed in a liquid phase portion of the accumulator.   The refrigeration cycle according to claim 1, wherein a flow rate control valve for adjusting a flow rate of a refrigerant introduced into the turbine is provided between the radiator and the turbine.   The refrigeration cycle according to claim 1, wherein the expansion device is provided integrally with the accumulator. One end opens to the gas phase part of the accumulator, the other end is connected to the compressor side, and a predetermined amount of liquid refrigerant in the liquid phase part is derived to a part of the tube wall passing through the liquid phase part of the accumulator. A refrigerant pipe provided with a throttle channel for mixing with the gas refrigerant sent from the gas phase part toward the compressor,
The refrigeration cycle according to claim 1, wherein a discharge path for the gas refrigerant led out from the pump is directly connected to the refrigerant pipe.   The refrigeration cycle according to claim 6, wherein a gas refrigerant lead-out path led out from the pump is directly connected to a pipe wall of a portion of the refrigerant pipe in a liquid phase part of the accumulator. The flow control valve is
A valve portion for opening and closing a refrigerant passage connecting the radiator and the turbine;
A solenoid that opens and closes the valve,
Control means for controlling opening and closing of the valve portion by duty control of current supplied to the solenoid;
The refrigeration cycle according to claim 4, further comprising: The inflator is
A valve unit that is disposed on the liquid phase side of the accumulator and controls the flow rate of the liquid refrigerant that exits the accumulator and is supplied to the evaporator;
A first temperature-sensitive actuator in which a load for biasing the valve portion in a valve opening direction is changed according to a temperature of a refrigerant that leaves the evaporator and enters the pump;
A second temperature-sensitive actuator that is disposed on the low-pressure side of the valve portion, and that changes a load that biases the valve portion in a valve-closing direction according to the temperature of the liquid refrigerant that has been squeezed and expanded by the valve portion;
The refrigeration cycle according to claim 5, further comprising:   The first temperature-sensitive actuator and the second temperature-sensitive actuator are each a shape memory alloy spring having a bidirectional shape memory effect in which a load changes in a predetermined temperature range. Item 10. The refrigeration cycle according to Item 9.   The refrigeration cycle according to claim 9, wherein the turbine pump is disposed in a liquid phase portion of the accumulator.   The refrigeration cycle according to claim 1, wherein the pump is of a rotary type and is configured to compress the refrigerant introduced from the evaporator in a rotation direction thereof.   The refrigeration cycle according to claim 1, wherein a refrigerant pressure after being compressed by the compressor is equal to or higher than a critical pressure of the refrigerant. A compressor that compresses the refrigerant, a radiator that cools the refrigerant discharged from the compressor, and an accumulator that stores the introduced refrigerant separated into gas and liquid, and sends the gas refrigerant toward the compressor And an expansion device that squeezes and expands the liquid refrigerant stored in the accumulator, and an evaporator that evaporates the refrigerant depressurized by the expansion device. ,
It is constructed by assembling the accumulator and the expansion device integrally,
Inside the accumulator, a turbine that is rotated by the refrigerant introduced from the radiator and discharges the refrigerant into the accumulator, and the refrigerant that is rotated together with the turbine and compressed from the evaporator is compressed into the accumulator. A turbine pump having a pump for discharging the gas into the accumulator,
A compression assisting device characterized by the above.   The compression assisting device according to claim 14, wherein a flow rate control valve for adjusting a flow rate of the refrigerant introduced from the radiator is integrally provided in the accumulator.   The compression assisting device according to claim 14, wherein the turbine pump is disposed in a liquid phase portion of the accumulator. One end opens to the gas phase part of the accumulator, the other end is connected to the compressor side, and a predetermined amount of liquid refrigerant in the liquid phase part is derived to a part of the tube wall passing through the liquid phase part of the accumulator. A refrigerant pipe provided with a throttle channel for mixing with the gas refrigerant sent from the gas phase part toward the compressor,
The compression auxiliary device according to claim 16, wherein a gas refrigerant lead-out path led out from the pump is directly connected to a pipe wall of a portion of the refrigerant pipe in a liquid phase portion of the accumulator.

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