CN113544085B

CN113544085B - Valve device

Info

Publication number: CN113544085B
Application number: CN202080016790.6A
Authority: CN
Inventors: 河本阳一郎; 押谷洋; 长野阳平; 小川博史; 内田和秀
Original assignee: Denso Corp
Current assignee: Denso Corp
Priority date: 2019-02-28
Filing date: 2020-02-26
Publication date: 2024-04-09
Anticipated expiration: 2040-02-26
Also published as: JP2020143786A; JP7014239B2; CN113544085A

Abstract

The valve device is provided with a main body (51), a valve body (52), and a control valve member (Y1), wherein the control valve member (Y1) changes the pressure acting on pressure chambers (51 g, 58 a), and the pressure chambers (51 g, 58 a) generate control pressure for moving the valve body (52). The control valve member (Y1) has: a base (Y11, Y121, Y13) formed with a refrigerant chamber (Y19), a first refrigerant hole (Y16) communicating with the refrigerant chamber (Y19) and with the pressure chamber (51 g, 58 a), and a second refrigerant hole (Y17, Y18) communicating with the refrigerant chamber (Y19) and with a refrigerant passage (51 c, 51 k) outside the control valve member (Y1); a driving unit (Y123, Y124, Y125) that displaces when the temperature of the driving unit itself changes; amplifying units (Y126, Y127) that amplify the displacement of the driving units (Y123, Y124, Y125) caused by the change in temperature; and a movable part (Y128) which moves in the refrigerant chamber (Y19) by transmitting the displacement amplified by the amplifying parts (Y126, Y127), thereby adjusting the opening degree of the second refrigerant holes (Y17, Y18) relative to the refrigerant chamber (Y19).

Description

Valve device

Cross-reference to related applications

The present application is based on Japanese patent application No. 2019-35222 filed on 28 of 2019 and Japanese patent application No. 2020-27187 filed on 20 of 2020, and the contents of the descriptions are incorporated herein by reference.

Technical Field

The present invention relates to a valve device for a refrigeration cycle.

Background

Patent document 1 describes the following technique: in an expansion valve used in a refrigeration cycle, a valve for adjusting a flow rate of a refrigerant is driven by a stepping motor.

Prior art literature

Patent literature

Patent document 1: japanese patent application laid-open No. 2015-14306

According to the study of the inventors, the expansion valve described in patent document 1 has a stepping motor, and therefore has a large size.

Disclosure of Invention

The present invention aims to easily reduce the size of a valve device such as an expansion valve used in a refrigeration cycle compared with the prior art.

According to one aspect of the present invention, a valve device for a refrigeration cycle includes:

a main body having an inflow port, an outflow port, and a valve chamber through which a refrigerant flowing from the inflow port to the outflow port flows;

a valve body that is displaced in the valve chamber to adjust a flow rate of the refrigerant flowing from the inflow port to the outflow port through the valve chamber; and

a control valve member that changes a pressure acting on a pressure chamber that generates a control pressure for moving the valve element,

the control valve member has:

A base portion formed with a refrigerant chamber through which a refrigerant flows, a first refrigerant hole that communicates with the refrigerant chamber and with the pressure chamber, and a second refrigerant hole that communicates with the refrigerant chamber and with a passage of the refrigerant outside the control valve member;

a driving unit that displaces when the temperature of the driving unit itself changes;

an amplifying unit that amplifies a displacement of the driving unit due to a change in temperature; and

a movable portion that moves in the refrigerant chamber by transmitting the displacement amplified by the amplifying portion, thereby adjusting the opening degree of the second refrigerant hole with respect to the refrigerant chamber,

when the driving part is displaced due to a change in temperature, the driving part applies force to the amplifying part at a force applying position, so that the amplifying part is displaced with a hinge as a fulcrum, and the amplifying part applies force to the movable part at a connecting position of the amplifying part and the movable part,

the distance from the hinge to the connection position is longer than the distance from the hinge to the force application position.

Since the amplifying portion of the control valve member configured as described above functions as a lever, the displacement amount of the driving portion corresponding to the temperature change is amplified by the lever and transmitted to the movable portion. In this way, the amount of displacement caused by thermal expansion is amplified by the lever, which contributes to miniaturization as compared with a valve device that does not use such a lever.

Further, the bracketed reference symbols attached to the respective constituent elements and the like indicate examples of correspondence between the constituent elements and the like and specific constituent elements and the like described in the embodiments described below.

Drawings

Fig. 1 is a diagram showing a configuration of a refrigeration cycle according to a first embodiment.

Fig. 2 is a view showing an installation form of the expansion valve.

Fig. 3 is a cross-sectional view of the expansion valve.

Fig. 4 is an enlarged cross-sectional view of the valve assembly of fig. 3 and its periphery.

Fig. 5 is an exploded view of the microvalve.

Fig. 6 is a front view of the microvalve.

Fig. 7 is a sectional view of VII-VII of fig. 6, showing a state when not energized.

Fig. 8 is a cross-sectional view of VIII-VIII of fig. 6, showing a state when not energized.

Fig. 9 is a sectional view VII-VII of fig. 6, showing a state when the maximum power is energized.

Fig. 10 is a cross-sectional view of VIII-VIII of fig. 6, showing a state when maximum power is applied.

Fig. 11 is a graph showing a relationship between the duty ratio and the pressure of the outputted refrigerant.

Fig. 12 is a cross-sectional view showing a state of the valve when the refrigerant circuit is not operating.

Fig. 13 is a cross-sectional view showing a state of the valve in the case where the duty ratio is zero when the refrigerant circuit is operated.

Fig. 14 is a cross-sectional view showing a state of the valve in the case where the duty ratio is 100% when the refrigerant circuit is operated.

Fig. 15 is a cross-sectional view of a microvalve in a second embodiment.

Fig. 16 is an enlarged view of the XVI portion of fig. 15.

Fig. 17 is a cross-sectional view of the expansion valve in the third embodiment.

Fig. 18 is a cross-sectional view of an expansion valve in the fourth embodiment.

Fig. 19 is a cross-sectional view of XIX-XIX of fig. 18.

FIG. 20 is a cross-sectional view of XX-XX of FIG. 19.

Fig. 21 is an XXI-oriented view of fig. 18.

Fig. 22 is an exploded view of the microvalve.

Fig. 23 is a cross-sectional view of the microvalve, shown in a non-energized state.

Fig. 24 is a cross-sectional view of the microvalve, showing the state when energized.

Fig. 25 is a cross-sectional view showing a state of the expansion valve when the expansion valve is opened.

Fig. 26 is a cross-sectional view showing a state of the expansion valve when the valve is closed.

Fig. 27 is a partial cross-sectional view of an expansion valve in the fifth embodiment.

Fig. 28 is a cross-sectional view of XXVIII-XXVIII of fig. 27.

Fig. 29 is a sectional view of an expansion valve in the sixth embodiment.

Fig. 30 is a cross-sectional view of an expansion valve in the seventh embodiment.

Fig. 31 is a cross-sectional view of an expansion valve in the eighth embodiment.

Fig. 32 is a cross-sectional view of XXXII-XXXII of fig. 31.

Fig. 33 is a cross-sectional view of an expansion valve in the ninth embodiment.

Fig. 34 is a sectional view of XXXIV-XXXIV of fig. 33.

Fig. 35 is a cross-sectional view of XXXV-XXXV of fig. 34.

Fig. 36 is a cross-sectional view of an expansion valve in the tenth embodiment.

Detailed Description

(first embodiment)

The first embodiment will be described below. As shown in fig. 1, the expansion valve 5 is an electric expansion valve, and is applied to a vapor compression refrigeration cycle 1 of a vehicle air conditioner. The refrigeration cycle 1 uses a freon-based refrigerant (R134 a) as a refrigerant, and constitutes a subcritical cycle in which the pressure of the high-pressure refrigerant does not exceed the critical pressure of the refrigerant. First, the compressor 2 of the refrigeration cycle 1 receives driving force from an engine for vehicle running, not shown, via an electromagnetic clutch or the like, and sucks in and compresses a refrigerant. The compressor 2 may be an electric compressor driven by a driving force output from an electric motor, not shown.

The condenser 3 is a heat-dissipating heat exchanger that exchanges heat between the high-pressure refrigerant discharged from the compressor 2 and outside air (i.e., air outside the vehicle) blown by a cooling fan (not shown), and dissipates heat of the high-pressure refrigerant to condense the high-pressure refrigerant.

A receiver 4 is connected to the outlet side of the condenser 3, and the receiver 4 separates the high-pressure refrigerant flowing out of the condenser 3 into a gas-phase refrigerant and a liquid-phase refrigerant, and accumulates the remaining liquid-phase refrigerant in the cycle. An expansion valve 5 is connected to the liquid-phase refrigerant outlet of the receiver 4. The expansion valve 5 is disposed on the vehicle cabin side of a firewall that separates the vehicle cabin from the outside.

The expansion valve 5 is a valve device for decompressing and expanding the high-pressure refrigerant flowing out from the receiver 4. The expansion valve 5 changes the throttle passage area (i.e., the valve opening degree) based on the temperature and pressure of the low-pressure refrigerant flowing out of the evaporator 6 so that the degree of superheat of the low-pressure refrigerant flowing out of the evaporator 6 approaches a predetermined value, thereby adjusting the flow rate of the refrigerant flowing out to the refrigerant inflow port side of the evaporator 6. The expansion valve 5 will be described in detail later. Temperature and pressure are physical quantities.

The evaporator 6 is disposed in an air conditioning case 7, and the air conditioning case 7 is disposed in a dashboard of the vehicle or the like. The evaporator exchanges heat between the low-pressure refrigerant decompressed and expanded by the expansion valve 5 and air flowing in the air conditioning case 7 by being forced by the blower 8. By this heat exchange, the air is cooled, and the low-pressure refrigerant evaporates. The cooled air is sent into the vehicle interior by the blower 8.

Next, the detailed structure of the expansion valve 5 will be described. As shown in fig. 2, the expansion valve 5 is fixed to the air conditioning case from the outside of the air conditioning case 7. The outlet side of the evaporator 6 is connected to the suction side of the compressor 2 via an evaporated refrigerant passage 51f formed inside the expansion valve 5.

As shown in fig. 2 and 3, the expansion valve 5 includes a main body 51, a valve body 52, a coil spring 53, a main body 54, a valve unit Y0, and the like. First, the main body 51 is a portion constituting a casing of the expansion valve 5, a refrigerant passage in the expansion valve 5, and the like, and is formed by punching a cylindrical or square cylindrical metal block. The main body 51 includes a first inlet 51a, a first outlet 51b, a second inlet 51d, a second outlet 51e, a valve chamber 51g, a throttle passage 51h, and the like.

A first inlet 51a connected to the outlet of the condenser 3 and allowing the high-pressure liquid-phase refrigerant to flow in, and a first outlet 51b allowing the refrigerant flowing in from the first inlet 51a to flow out to the inlet side of the evaporator 6 are formed as the refrigerant inflow port and the refrigerant outflow port. Therefore, in the present embodiment, the high-pressure refrigerant passage 51c is formed by the refrigerant passage from the first inflow port 51a to the first outflow port 51b. The high-pressure refrigerant passage 51c corresponds to the first passage.

A second inlet 51d through which the low-pressure refrigerant flowing out of the evaporator 6 flows in and a second outlet 51e through which the refrigerant flowing in through the second inlet 51d flows out to the suction side of the compressor 2 are formed as the other refrigerant inflow port and outflow port. Therefore, in the present embodiment, the evaporated refrigerant passage 51f is formed by the refrigerant passage from the second inflow port 51d to the second outflow port 51e.

The valve chamber 51g is a space provided in the high-pressure refrigerant passage 51c and accommodating a valve body 52 described later therein. The valve chamber 51g corresponds to a pressure chamber. More specifically, the valve chamber 51g communicates directly with the first inflow port 51a, and communicates with the first outflow port 51b via the throttle passage 51 h. The throttle passage 51h is provided in the high-pressure refrigerant passage 51c, and guides the refrigerant flowing into the valve chamber 51g from the first inlet 51a from the valve chamber 51g to the first outlet 51b while decompressing and expanding the refrigerant flowing into the valve chamber 51g from the first inlet 51 a. The throttle passage 51h is formed between the spool 52 and the valve seat 51 j.

The valve seat 51j is formed in the main body 51 so as to narrow the refrigerant flow path at the downstream end of the valve chamber 51 g. The valve body 52 is a valve body that continuously or in a plurality of three or more stages adjusts the refrigerant passage area of the throttle passage 51h by displacement with respect to the valve seat 51 j. The refrigerant passage from the throttle passage 51h to the first outflow port 51b is a low-pressure refrigerant passage 51k. The low-pressure refrigerant passage 51k corresponds to the second passage.

The low-pressure refrigerant passage 51k is connected to a low-pressure introduction passage 51q. The low pressure introduction path 51q is formed in the main body 51, and has one end communicating with the low pressure refrigerant path 51k and the other end communicating with the third communication hole YV3 of the valve assembly Y0.

The high-pressure introduction passage 51P is connected to the high-pressure refrigerant passage 51 c. The high-pressure introduction path 51P is formed in the main body 51, and has one end communicating with the high-pressure refrigerant path 51c and the other end communicating with the second communication hole YV2 of the valve assembly Y0.

The coil spring 53 is accommodated in the valve chamber 51g, and biases the valve body 52 to the side closing the throttle passage 51 h. Specifically, the coil spring 53 is disposed in the back pressure chamber 51m in the valve chamber 51 g. The back pressure chamber 51m is formed on the opposite side of the throttle passage 51h with respect to the spool 52. The back pressure chamber 51m communicates with the first communication hole YV1 of the valve assembly Y0. Hereinafter, a space of the valve chamber 51g on the opposite side of the back pressure chamber 51m with respect to the valve body 52 is referred to as a front side chamber 51s. The valve chamber 51g is partitioned by the valve body 52 into a back pressure chamber 51m and a front side chamber 51s.

The autonomous unit 54 includes a housing 54a, a circuit board 54b, a composite sensor 54c, and a drive circuit 54d. The case 54a is fixed to the main body 51, and is a resin member surrounding a housing space in which the circuit board 54b, the composite sensor 54c, and the drive circuit 54d are housed. An opening 51r that opens to the accommodating space is formed in a wall surrounding the evaporated refrigerant passage 51f in the main body 51. The circuit board 54b is fixed to the case 54a, and the composite sensor 54c, the driving circuit 54d, and the like are mounted thereon.

The composite sensor 54c includes a housing 541, a sensing portion 542, a lead portion 543, and an O-ring 544. The resin case 541 is integrally fixed to the main body 51 in the housing space surrounded by the case 54 a. More specifically, the housing 541 is inserted into the opening 51r formed in the main body 51. Therefore, the housing 541 has a portion located in the evaporated refrigerant passage 51f and a portion located in the above-described accommodation space.

The O-ring 544 is interposed between the case 541 and the main body 51, and suppresses leakage of the refrigerant from the evaporated refrigerant passage 51f into the case 54 a. The conductive lead portion 543 is connected to wiring printed on the circuit board 54 b. The composite sensor 54c faces the circuit board 54b through the gap, and therefore, the lead portion 543 is easily arranged.

The sensing portion 542 is fixed to a portion of the housing 541 located in the evaporated refrigerant passage 51 f. The sensing portion 542 outputs a pressure signal corresponding to the pressure of the refrigerant in the evaporated refrigerant passage 51f and a temperature signal corresponding to the temperature of the refrigerant in the evaporated refrigerant passage 51 f.

The sensing unit 542 may include, for example, a pressure sensor and a temperature sensor separate from the pressure sensor. Alternatively, the sensing portion 542 may have four measuring resistors and a thin-walled diaphragm to which the bridge circuit is attached. Each of the weighing resistors may be formed as a thin film resistor formed on the diaphragm.

Each of the measuring resistors is a resistor element whose resistance value changes according to the strain of the diaphragm. Each of the measuring resistors is an element whose resistance value varies according to temperature. The metering resistors are electrically connected to each other in a manner that forms a wheatstone bridge circuit. A constant current is supplied from the drive circuit 54d to the wheatstone bridge circuit through the circuit board 54b, the lead portion 543, and a wiring not shown. Accordingly, the pressure signal corresponding to the strain of the diaphragm and the temperature signal corresponding to the temperature of the diaphragm are output from the sensing unit 542 by the piezoresistive effect of each measuring resistor.

Specifically, the sensing unit 542 detects a change in resistance of a plurality of gauge resistors corresponding to a strain of the diaphragm as a change in midpoint voltage of the wheatstone bridge circuit, and outputs the midpoint voltage as a pressure signal. On the other hand, the sensing unit 542 detects a change in resistance of a plurality of measuring resistors corresponding to the temperature of the sensing unit 542 as a bridge voltage of the wheatstone bridge circuit, and outputs the bridge voltage as a temperature signal.

The pressure signal and the temperature signal outputted from the sensing portion 542 are transmitted from the sensing portion 542 to the circuit board 54b via a wiring, not shown, and a lead portion 543 connected to the wiring. The pressure signal and the temperature signal transmitted to the circuit substrate 54b are input to the driving circuit 54d via the pattern printed on the circuit substrate 54b.

The drive circuit 54d controls the operation of the valve assembly Y0 based on the pressure signal and the temperature signal input from the composite sensor 54c via the circuit substrate 54 b. The driving circuit 54d can be implemented by, for example, a microcomputer, or can also be implemented by hardware having a dedicated circuit configuration.

[ Structure of valve Assembly Y0 ]

The structure of the valve assembly Y0 will be described with reference to fig. 3, 4, 5, 6, 7, and 8. As shown in fig. 3 and 4, the valve assembly Y0 includes a micro valve Y1, a valve housing Y2, a sealing member Y3, three O-rings Y4, Y5a, and Y5b, two harnesses Y6, Y7, and a switching plate Y8.

The micro valve Y1 is a plate-shaped control valve member and is mainly composed of a semiconductor chip. The micro valve Y1 may not have any component other than the semiconductor chip. Therefore, the micro valve Y1 can be made compact. The length of the micro valve Y1 in the thickness direction is, for example, 2mm, the length of the micro valve in the length direction perpendicular to the thickness direction is, for example, 10mm, and the length of the micro valve in the short side direction perpendicular to both the length direction and the thickness direction is, for example, 5mm, but the present invention is not limited thereto. The flow path structure of the micro valve Y1 changes due to the fluctuation of the supply power to the micro valve Y1. The micro valve Y1 functions as a pilot valve.

The harness lines Y6 and Y7 extend from the surface on the opposite side of the valve housing Y2 from the two surface plates on the front and rear surfaces of the micro valve Y1, and are connected to a power source (i.e., the drive circuit 54 d) located outside the valve assembly Y0 through the sealing member Y3 and the inside of the valve housing Y2. The ends of the harnesses Y6 and Y7 on the opposite side of the micro valve Y1 are connected to the drive circuit 54 d. Thus, electric power can be supplied from the drive circuit 54d to the micro valve Y1 through the harnesses Y6 and Y7.

The switching plate Y8 is a plate-shaped member disposed between the micro valve Y1 and the valve housing Y2. The conversion plate Y8 is a glass substrate. One side of two plate surfaces located on the front and rear surfaces of the conversion plate Y8 is fixed to the micro valve Y1 by an adhesive, and the other side is fixed to the valve housing Y2 by an adhesive. The switching plate Y8 is formed with flow paths Y81, Y82, and Y83 for connecting three refrigerant holes Y16, Y17, and Y18 of the micro valve Y1 to three communication holes YV1, YV2, and YV3 of the valve housing Y2, which will be described later. These flow paths Y81, Y82, Y83 are flow paths for absorbing differences in the pitch between the three refrigerant holes Y16, Y17, Y18 aligned in a row and the pitch between the three communication holes YV1, YV2, YV3 aligned in a row. The pitch between the communication holes YV1, YV2, YV3 is larger than the pitch between the refrigerant holes Y16, Y17, Y18. The channels Y81, Y82, Y83 pass through one of the two plate surfaces located on the front and rear surfaces of the conversion plate Y8 to the other. Therefore, the pitch between the ends of the passages Y81, Y82, Y83 on the communication holes YV1, YV2, YV3 side is larger than the pitch between the ends of the passages Y81, Y82, Y83 on the refrigerant holes Y16, Y17, Y18 side.

The valve housing Y2 is a resin housing that accommodates the micro valve Y1 and the switching plate Y8. The valve housing Y2 is formed by resin molding using polyphenylene sulfide as a main component. The valve housing Y2 is a case having a bottom wall on one side and an opening on the other side. The bottom wall of the valve housing Y2 is sandwiched between the main body 51 and the micro valve Y1 in such a manner that the micro valve Y1 and the switching plate Y8 are not in direct contact with the main body 51. The bottom wall is fixed with one surface thereof in contact with the main body 51 and the other surface thereof in contact with the conversion plate Y8.

With this configuration, the valve housing Y2 can absorb the difference in linear expansion coefficient between the micro valve Y1 and the main body 51. This is because the linear expansion coefficient of the valve housing Y2 is a value between the linear expansion coefficient of the micro valve Y1 and the linear expansion coefficient of the main body 51. The linear expansion coefficient of the conversion plate Y8 is a value between the linear expansion coefficient of the micro valve Y1 and the linear expansion coefficient of the valve housing Y2.

The bottom wall of the valve housing Y2 has a plate-shaped base portion Y20 facing the micro valve Y1, and column-shaped first, second, and third protruding portions Y21, Y22, Y23 protruding from the base portion Y20 in a direction away from the micro valve Y1.

The first, second and third protruding portions Y21, Y22, Y23 are fitted into recesses formed in the main body 51. The first protrusion Y21 has a first communication hole YV1 extending from the side end of the micro valve Y1 to the opposite side end thereof. The second protruding portion Y22 has a second communication hole YV2 extending from the side end of the micro valve Y1 to the opposite side end thereof. The third protruding portion Y23 has a third communication hole YV3 formed therethrough from the side end of the micro valve Y1 to the opposite side end thereof. The first communication hole YV1, the second communication hole YV2, and the third communication hole YV3 are aligned in a row, and the first communication hole YV1 is located between the second communication hole YV2 and the third communication hole YV3.

The micro valve Y1 side end of the first communication hole YV1 communicates with the valve housing Y2 side end of the flow path Y81 formed in the switching plate Y8. The micro valve Y1 side end of the second communication hole YV2 communicates with the valve housing Y2 side end of the flow path Y82 formed in the switching plate Y8. The micro valve Y1 side end of the third communication hole YV3 communicates with the valve housing Y2 side end of the flow path Y83 formed in the switching plate Y8.

The sealing member Y3 is an epoxy resin member that seals the other side of the opening of the valve housing Y2. The sealing member Y3 covers the entire surface of the plate surface on the opposite side to the conversion plate Y8 side of the two plate surfaces on the front and rear surfaces of the micro valve Y1. The seal member Y3 covers a part of the plate surface on the opposite side to the bottom wall side of the valve housing Y2, out of the two plate surfaces on the front and rear surfaces of the conversion plate Y8. The sealing member Y3 covers the harnesses Y6 and Y7 to prevent water and insulate the harnesses Y6 and Y7. The sealing member Y3 is formed by resin potting or the like.

The O-ring Y4 is attached to the outer periphery of the first protruding portion Y21, and seals between the main body 51 and the first protruding portion Y21, thereby suppressing leakage of the refrigerant to the outside of the expansion valve 5 and the outside of the refrigeration cycle. The O-ring Y5a is attached to the outer periphery of the second protruding portion Y22, and seals between the main body 51 and the second protruding portion Y22, thereby suppressing leakage of the refrigerant to the outside of the expansion valve 5 and the outside of the refrigeration cycle. The O-ring Y5b is attached to the outer periphery of the third protruding portion Y23, and seals between the body 51 and the third protruding portion Y23, thereby suppressing leakage of the refrigerant to the outside of the expansion valve 5 and the outside of the refrigeration cycle.

The structure of the micro valve Y1 will be further described. As shown in fig. 5 and 6, the micro valve Y1 is a MEMS including a first outer layer Y11, an intermediate layer Y12, and a second outer layer Y13, each of which is a semiconductor. MEMS is a short for Micro Electro Mechanical Systems (microelectromechanical systems). The first outer layer Y11, the intermediate layer Y12, and the second outer layer Y13 are rectangular plate-shaped members each having the same outer shape, and are laminated in this order of the first outer layer Y11, the intermediate layer Y12, and the second outer layer Y13. That is, the intermediate layer Y12 is sandwiched by the first outer layer Y11 and the second outer layer Y13 from both sides. The second outer layer Y13 of the first outer layer Y11, the intermediate layer Y12, and the second outer layer Y13 is disposed on the side of the valve housing Y2 closest to the bottom wall. The structures of the first outer layer Y11, the intermediate layer Y12, and the second outer layer Y13 described later are formed by a semiconductor manufacturing process such as chemical etching.

The first outer layer Y11 is a conductive semiconductor member having a nonconductive oxide film on the surface. As shown in fig. 5, two through holes Y14 and Y15 penetrating to the front and rear surfaces are formed in the first outer layer Y11. The micro valve Y1 side ends of the harnesses Y6, Y7 are inserted into the through holes Y14, Y15, respectively.

The second outer layer Y13 is a conductive semiconductor member having a nonconductive oxide film on the surface. As shown in fig. 5, 7, and 8, the second outer layer Y13 has first, second, and third refrigerant holes Y16, Y17, Y18 penetrating the front and rear surfaces.

As shown in fig. 8, the first, second, and third refrigerant holes Y16, Y17, Y18 communicate with the flow paths Y81, Y82, Y83 of the switching plate Y8, respectively. The first, second and third refrigerant holes Y16, Y17 and Y18 are arranged in a row. The first refrigerant hole Y16 is disposed between the second refrigerant hole Y17 and the third refrigerant hole Y18. The hydraulic diameters of the first, second, and third refrigerant holes Y16, Y17, and Y18 are, for example, 0.1mm to 3mm, but are not limited thereto.

The intermediate layer Y12 is a conductive semiconductor member, and is sandwiched between the first outer layer Y11 and the second outer layer Y13. The intermediate layer Y12 is in contact with the oxide film of the first outer layer Y11 and the oxide film of the second outer layer Y13, and thus is electrically non-conductive to both the first outer layer Y11 and the second outer layer Y13. As shown in fig. 7, the intermediate layer Y12 has a first fixed portion Y121, a second fixed portion Y122, a plurality of first ribs Y123, a plurality of second ribs Y124, a spine (spine) Y125, an arm Y126, a beam Y127, and a movable portion Y128.

The first fixing portion Y121 is a member fixed to the first outer layer Y11 and the second outer layer Y13. The first fixed portion Y121 is formed so as to enclose the second fixed portion Y122, the first rib Y123, the second rib Y124, the spine Y125, the arm Y126, the beam Y127, and the movable portion Y128 in the same one refrigerant chamber Y19. The refrigerant chamber Y19 is a chamber surrounded by the first fixing portion Y121, the first outer layer Y11, and the second outer layer Y13. The first fixing portion Y121, the first outer layer Y11, and the second outer layer Y13 correspond to the base as a whole. The harnesses Y6 and Y7 are harnesses for shifting the temperature of the first ribs Y123 and the second ribs Y124 by changing them.

The first fixing portion Y121 is fixed to the first outer layer Y11 and the second outer layer Y13 in the following manner: the refrigerant is prevented from leaking from the micro valve Y1 through the refrigerant chamber Y19, except through the first refrigerant hole Y16, the second refrigerant hole Y17, and the third refrigerant hole Y18.

The second fixing portion Y122 is fixed to the first outer layer Y11 and the second outer layer Y13. The second fixing portion Y122 is surrounded by the first fixing portion Y121, and is disposed separately from the first fixing portion Y121.

The plurality of first ribs Y123, the plurality of second ribs Y124, the spine Y125, the arm Y126, the beam Y127, and the movable portion Y128 are not fixed to the first outer layer Y11 and the second outer layer Y13, and are displaceable relative to the first outer layer Y11 and the second outer layer Y13.

The spine Y125 has an elongated rod shape extending in the short side direction of the rectangular shape of the intermediate layer Y12. One end of the spine Y125 in the longitudinal direction is connected to the beam Y127.

The plurality of first ribs Y123 are arranged on one side of the spine Y125 in a direction orthogonal to the longitudinal direction of the spine Y125. Also, a plurality of first ribs Y123 are aligned along the length direction of the spine Y125. Each of the first ribs Y123 has a slender rod shape and is expandable and contractible according to temperature.

Each of the first ribs Y123 is connected to the first fixing portion Y121 at one end in the longitudinal direction thereof and to the spine Y125 at the other end. The first ribs Y123 are inclined with respect to the spine Y125 so as to be offset toward the beam Y127 side in the longitudinal direction of the spine Y125 as approaching the spine Y125 from the first fixing portion Y121 side. Also, the plurality of first ribs Y123 extend parallel to each other.

The plurality of second ribs Y124 are arranged on the other side of the spine Y125 in the direction orthogonal to the longitudinal direction of the spine Y125. Also, a plurality of second ribs Y124 are aligned along the length of the spine Y125. Each of the second ribs Y124 has an elongated rod shape and is expandable and contractible according to temperature.

Each of the second ribs Y124 is connected to the second fixing portion Y122 at one end in the longitudinal direction thereof and to the spine Y125 at the other end. The second ribs Y124 are inclined with respect to the spine Y125 so as to be offset toward the beam Y127 side in the longitudinal direction of the spine Y125 as they approach the spine Y125 from the second fixing portion Y122 side. Also, the plurality of second ribs Y124 extend parallel to each other.

The plurality of first ribs Y123, the plurality of second ribs Y124, and the spine Y125 correspond to the driving unit as a whole.

The arm Y126 has an elongated rod shape extending non-orthogonally and parallel to the spine Y125. One end of the arm Y126 in the longitudinal direction is connected to the beam Y127, and the other end is connected to the first fixing portion Y121.

Beam Y127 has an elongated rod shape extending in a direction intersecting at about 90 ° with respect to spine Y125 and arm Y126. One end of the beam Y127 is connected to the movable portion Y128. The arm Y126 and the beam Y127 as a whole correspond to the amplifying section.

The connection position YP1 of the arm Y126 and the beam Y127, the connection position YP2 of the spine Y125 and the beam Y127, and the connection position YP3 of the beam Y127 and the movable portion Y128 are arranged in this order along the longitudinal direction of the beam Y127. Further, when the joint between the first fixing portion Y121 and the arm Y126 is the hinge YP0, the linear distance from the hinge YP0 to the joint position YP3 is longer than the linear distance from the hinge YP0 to the joint position YP2 in the plane parallel to the plate surface of the intermediate layer Y12. For example, the value obtained by dividing the linear distance of the former by the linear distance of the latter may be 1/5 or less, or may be 1/10 or less.

The movable portion Y128 has a rectangular shape extending in a direction of substantially 90 ° with respect to the longitudinal direction of the beam Y127. The movable portion Y128 is movable integrally with the beam Y127 in the refrigerant chamber Y19. The movable portion Y128 has a frame shape surrounding the through-hole Y120 penetrating the front and rear surfaces of the intermediate layer Y12. Accordingly, the through-hole Y120 moves integrally with the movable portion Y128. The through-hole Y120 is a part of the refrigerant chamber Y19.

The movable portion Y128 changes the opening degree of the second refrigerant hole Y17 with respect to the through hole Y120 and the opening degree of the third refrigerant hole Y18 with respect to the through hole Y120 by moving as described above. The first refrigerant hole Y16 is always in full-open communication with the through hole Y120.

The micro valve Y1 side end of the harness Y6 passing through the through hole Y14 of the first outer layer Y11 shown in fig. 5 is connected to a first application point Y129 near a portion of the first fixing portion Y121 connected to the plurality of first ribs Y123. The micro valve Y1 side end of the harness Y7 passing through the through hole Y15 of the first outer layer Y11 shown in fig. 5 is connected to the second application point Y130 of the second fixing portion Y122.

[ operation of valve Assembly Y0 ]

Here, the operation of the valve assembly Y0 will be described. When the energization of the micro valve Y1 is started, a voltage is applied from the electric wires Y6 and Y7 to the first application point Y129 and the second application point Y130. Then, the current flows in the plurality of first ribs Y123 and the plurality of second ribs Y124. The plurality of first ribs Y123 and the plurality of second ribs Y124 generate heat due to the current. As a result, the plurality of first ribs Y123 and the plurality of second ribs Y124 expand in the longitudinal direction thereof.

As a result of such thermal expansion, the plurality of first ribs Y123 and the plurality of second ribs Y124 urge the spine Y125 toward the connection position YP 2. The urged spine Y125 presses the beam Y127 at the connection position YP 2. Thus, the connection position YP2 corresponds to the urging position. As a result, the member composed of the beam Y127 and the arm Y126 changes its posture integrally with the hinge YP0 as a fulcrum and the connection position YP2 as a force point. As a result, the movable portion Y128 connected to the end of the beam Y127 opposite to the arm Y126 also moves to the side of the longitudinal direction thereof where the spine Y125 presses the beam Y127.

When the energization to the micro valve Y1 is stopped, the voltage application from the harnesses Y6 and Y7 to the first application point Y129 and the second application point Y130 is stopped. Then, the current does not flow through the plurality of first ribs Y123 and the plurality of second ribs Y124, and the temperatures of the plurality of first ribs Y123 and the plurality of second ribs Y124 decrease. As a result, the plurality of first ribs Y123 and the plurality of second ribs Y124 shrink in the longitudinal direction thereof.

As a result of such thermal shrinkage, the plurality of first ribs Y123 and the plurality of second ribs Y124 apply forces to the spine Y125 on the opposite side of the connection position YP 2. The applied spinal column Y125 stretches the beam Y127 at the connection position YP 2. As a result, the member composed of the beam Y127 and the arm Y126 changes its posture integrally with the hinge YP0 as a fulcrum and the connection position YP2 as a force point. As a result, the movable portion Y128 connected to the end of the beam Y127 opposite to the arm Y126 also moves to the side of the spine Y125 stretching the beam Y127 in the longitudinal direction thereof. As a result of this movement, the movable portion Y128 is stopped at a predetermined non-energized position. The non-energized position corresponds to the first position.

When such a micro valve Y1 is energized, the greater the electric power supplied from the harnesses Y6, Y7 to the micro valve Y1 via the first application point Y129 and the second application point Y130, the greater the amount of movement of the movable portion Y128 relative to the non-energized position. This is because the higher the power supplied to the micro valve Y1, the higher the temperatures of the first rib Y123 and the second rib Y124, and the greater the degree of expansion.

For example, when the voltages applied from the harnesses Y6 and Y7 to the first and second application points Y129 and Y130 are PWM-controlled, the larger the duty ratio of the voltage is, the larger the amount of movement of the movable portion Y128 from the position at the time of non-energization is. Hereinafter, the duty ratio of the voltage in PWM control will be simply referred to as the duty ratio.

As shown in fig. 7 and 8, when the movable portion Y128 is in the non-energized state, the through hole Y120 overlaps the first refrigerant hole Y16 and the third refrigerant hole Y18 in a direction orthogonal to the plate surface of the intermediate layer Y12, but does not overlap the second refrigerant hole Y17 in this direction. The second refrigerant hole Y17 overlaps the movable portion Y128 in a direction orthogonal to the plate surface of the intermediate layer Y12. That is, at this time, the first refrigerant hole Y16 and the third refrigerant hole Y18 are fully opened with respect to the through hole Y120, and the second refrigerant hole Y17 is fully closed with respect to the through hole Y120. Therefore, in this case, the first refrigerant hole Y16 communicates with the third refrigerant hole Y18 via the movable portion Y128, and the second refrigerant hole Y17 is cut off from both the first refrigerant hole Y16 and the third refrigerant hole Y18. As a result, the refrigerant can flow between the first communication hole YV1 and the third communication hole YV3 through the flow path Y81, the first refrigerant hole Y16, the through hole Y120, the third refrigerant hole Y18, and the flow path Y83.

As shown in fig. 9 and 10, when the movable portion Y128 is located at the position farthest from the non-energized state position due to the energization to the micro valve Y1, the position of the movable portion Y128 at this time is referred to as the maximum energized state position. The position at maximum power-on corresponds to the second position. When the movable portion Y128 is at the maximum energization position, the electric power supplied to the micro valve Y1 is at the maximum in the control range. For example, when the movable portion Y128 is at the maximum energization position, the duty ratio is the maximum value (for example, 100%) in the control range in the PWM control described above.

When the movable portion Y128 is at the maximum current-carrying position, the through hole Y120 overlaps the first refrigerant hole Y16 and the second refrigerant hole Y17 in a direction perpendicular to the plate surface of the intermediate layer Y12, but does not overlap the third refrigerant hole Y18 in this direction. The third refrigerant hole Y18 overlaps the movable portion Y128 in a direction orthogonal to the plate surface of the intermediate layer Y12. That is, at this time, the first refrigerant hole Y16 and the second refrigerant hole Y17 are fully opened with respect to the through hole Y120, and the third refrigerant hole Y18 is fully closed with respect to the through hole Y120. Therefore, in this case, the first refrigerant hole Y16 communicates with the second refrigerant hole Y17 via the movable portion Y128, and the third refrigerant hole Y18 is cut off from both the first refrigerant hole Y16 and the second refrigerant hole Y17. As a result, the refrigerant can flow between the first communication hole YV1 and the second communication hole YV2 through the flow path Y81, the first refrigerant hole Y16, the through hole Y120, the second refrigerant hole Y17, and the flow path Y83.

In addition, the electric power supplied to the micro valve Y1 (for example, in PWM control) is adjusted in a plurality of stages or continuously within a range of less than the maximum electric power and greater than zero. Thus, the movable portion Y128 can be stopped at any intermediate position between the non-energized state position and the maximum energized state position. For example, the movable portion Y128 may be stopped at a position (i.e., a center position) equidistant from the maximum power-on position and the non-power-on position, and the electric power to be supplied to the micro valve Y1 may be half of the maximum value within the control range. For example, the duty ratio in PWM control may be 50%.

When the movable portion Y128 is stopped at the intermediate position, the first refrigerant hole Y16, the second refrigerant hole Y17, and the third refrigerant hole Y18 communicate with the through hole Y120. However, the second refrigerant hole Y17 and the third refrigerant hole Y18 are not fully opened with respect to the through hole Y120, but have an intermediate opening degree of less than 100% and greater than 0%. The intermediate opening degree of the third refrigerant hole Y18 with respect to the through hole Y120 decreases as the movable portion Y128 approaches the maximum on-potential time position in the intermediate position, and the intermediate opening degree of the second refrigerant hole Y17 increases.

In the present embodiment, as described later, a high pressure is applied to the second refrigerant hole Y17, and a low pressure higher than the high pressure is applied to the third refrigerant hole Y18. At this time, when the movable portion Y128 is at the intermediate position, an intermediate pressure higher than the low pressure and lower than the high pressure acts from the first refrigerant hole Y16 to the outside of the micro valve Y1. The value of the intermediate pressure varies according to the opening degree of the second refrigerant hole Y17 with respect to the movable portion Y128 and the opening degree of the third refrigerant hole Y18 with respect to the movable portion Y128.

Fig. 11 illustrates a relationship between a duty ratio in the case of PWM-controlling the voltages applied from the harnesses Y6, Y7 to the first and second application points Y129, Y130 and a pressure (i.e., a control pressure or an outlet pressure) applied from the first refrigerant hole Y16 to the outside of the micro valve Y1. As shown in the figure, the larger the duty ratio is, the higher the control pressure becomes in proportion to the amount of increase in the duty ratio. When the duty ratio is 100%, the control pressure corresponds to the high pressure. When the duty ratio is 0%, that is, when the electric current is not applied, the control pressure matches the low pressure.

As described above, the beam Y127 and the arm Y126 function as levers with the hinge YP0 as a fulcrum, the connection position YP2 as a force point, and the connection position YP3 as an action point. As described above, the linear distance from the hinge YP0 to the connection position YP3 is longer than the linear distance from the hinge YP0 to the connection position YP2 in the plane parallel to the plate surface of the intermediate layer Y12. Therefore, the movement amount of the connection position YP3 as the action point is larger than the movement amount of the connection position YP2 as the force point. Therefore, the displacement amount due to thermal expansion is amplified by the lever and transmitted to the movable portion Y128.

In addition, the flow path of the refrigerant in the micro valve Y1 has a U-turn configuration. Specifically, the refrigerant flows into the micro valve Y1 from one surface of the micro valve Y1, passes through the micro valve Y1, and then flows out of the micro valve Y1 from the same surface of the micro valve Y1. Likewise, the flow path of the refrigerant in the valve assembly Y0 also has a U-turn configuration. Specifically, the refrigerant flows into the valve assembly Y0 from one side surface of the valve assembly Y0, passes through the valve assembly Y0, and flows out of the valve assembly Y0 from the same side surface of the valve assembly Y0. This is because, as described above, the first refrigerant hole Y16, the second refrigerant hole Y17, and the third refrigerant hole Y18 are formed in the same intermediate layer Y12. The direction perpendicular to the plate surface of the intermediate layer Y12 is the lamination direction of the first outer layer Y11, the intermediate layer Y12, and the second outer layer Y13.

The micro valve Y1 thus constructed can be easily miniaturized as compared with the solenoid valve and the stepping motor. One of the reasons for this is that the micro valve Y1 is formed of a semiconductor chip as described above. Further, as described above, the use of the lever to amplify the amount of displacement caused by thermal expansion also contributes to miniaturization as compared with a valve device using a solenoid valve or a stepping motor without using such a lever. Further, since the displacements of the plurality of first ribs Y123 and the plurality of second ribs Y124 are generated by heat, the noise reduction effect is high.

Further, since the lever is used, the amount of displacement due to thermal expansion can be suppressed as compared with the amount of movement of the movable portion Y128, and therefore the power consumption for driving the movable portion Y128 can be reduced. In addition, since the impact sound at the time of driving the solenoid valve can be eliminated, noise can be reduced.

As described above, since the micro valve Y1 and the valve assembly Y0 each have a U-turn structured refrigerant flow path, the scooping-in of the main body 51 can be reduced. That is, the depth of the recess formed in the main body 51 for disposing the valve assembly Y0 can be suppressed. The reason for this is as follows.

For example, it is assumed that the valve assembly Y0 does not have a refrigerant flow path having a U-turn structure, that a surface of the valve assembly Y0 on the main body 51 side has a refrigerant inflow port, and that a surface of the valve assembly Y0 on the opposite side has a refrigerant outlet port. In this case, it is necessary to form the refrigerant flow paths on both sides of the valve assembly Y0. Therefore, if the refrigerant flow paths to both sides of the valve unit Y0 are to be housed in the main body 51, the recess that must be formed in the main body 51 to dispose the valve unit Y0 becomes deep. In addition, since the micro valve Y1 itself is small, the penetration of the main body 51 can be further reduced.

In addition, when the harnesses Y6 and Y7 are arranged on the opposite surfaces of the two surfaces of the micro valve Y1 from the surface on which the first and second refrigerant holes Y16 and Y17 are formed, the harnesses Y6 and Y7 can be placed on the side closer to the atmosphere. Therefore, a sealing structure such as an airtight portion for reducing the influence of the refrigerant atmosphere on the harnesses Y6 and Y7 is not required. As a result, the expansion valve 5 can be miniaturized.

Further, since the micro valve Y1 is lightweight, the expansion valve 5 is lightweight. Further, since the consumed power of the micro valve Y1 is small, the expansion valve 5 is power-saving.

[ Whole work ]

Hereinafter, the operation of the refrigeration cycle configured as described above will be described.

[ non-runtime ]

First, a non-operation of the refrigeration cycle will be described. In this case, the compressor 2 and the blower 8 are not operated, and the refrigerant in the refrigeration cycle is not circulated. In addition, neither the complex sensor 54c nor the drive circuit 54d operates. In addition, no current is supplied to the micro valve Y1. In this case, as already described, the third communication hole YV3 communicates with the first communication hole YV1 via the micro valve Y1, and the second communication hole YV2 is cut off from the through hole Y120 of the micro valve Y1. Therefore, as shown in fig. 12, the back pressure chamber 51m and the low-pressure refrigerant passage 51k communicate with each other via the low-pressure introduction passage 51q and the micro valve Y1.

In addition, at this time, the pressure of the refrigerant between the receiver 4 and the expansion valve 5 and the pressure of the refrigerant between the expansion valve 5 and the evaporator 6 are equal to each other. Therefore, the pressure of the refrigerant in the high-pressure refrigerant passage 51c and the pressure of the refrigerant in the low-pressure refrigerant passage 51k are also equal to each other. Therefore, the pressure of the refrigerant in the back pressure chamber 51m communicating with the low-pressure refrigerant passage 51k and the pressure of the front side chamber 51s communicating with the high-pressure refrigerant passage 51c are also equal to each other.

Therefore, the force applied to the valve body 52 by the refrigerant in the back pressure chamber 51m is substantially the same as the force applied to the valve body 52 by the refrigerant in the front side chamber 51 s. Thereby, the valve body 52 moves to contact the valve seat 51j by the force of the compressed coil spring 53 to be expanded, and the throttle passage 51h is closed.

[ runtime ]

Next, a state in which the refrigeration cycle is operating will be described. In this case, the compressor 2 and the blower 8 are operated. Thereby, the pressure of the refrigerant in the high-pressure refrigerant passage 51c is higher than the pressure of the refrigerant in the low-pressure refrigerant passage 51 k.

The combination sensor 54c and the drive circuit 54d also operate. Accordingly, the micro valve Y1 is energized from the driving circuit 54d via the harnesses Y6, Y7 as needed.

Specifically, the combination sensor 54c detects the pressure and temperature of the refrigerant to pass through the post-evaporation refrigerant passage 51 f. That is, the temperature sensing portion of the composite sensor 54c outputs a pressure signal and a temperature signal corresponding to the pressure and the temperature of the refrigerant to be passed through the evaporated refrigerant passage 51f, respectively. The drive circuit 54d obtains the pressure signal and the temperature signal, and determines the electric power to be supplied to the harnesses Y6 and Y7 based on the obtained pressure signal and temperature signal. In the following, the case where the drive circuit 54d performs the power supply to the harnesses Y6 and Y7 by PWM control with a constant maximum voltage will be described. Accordingly, the driving circuit 54d determines the duty ratio of the voltage applied to the harnesses Y6, Y7 based on the obtained pressure signal and temperature signal so that the degree of superheat of the low-pressure refrigerant flowing out of the evaporator 6 becomes a predetermined constant value.

Specifically, the driving circuit 54d makes the duty ratio smaller as the pressure indicated by the pressure signal is constant and the temperature indicated by the temperature signal is higher, that is, as the degree of superheat is higher. This increases the lift amount of the valve body 52 and decreases the degree of superheat. The driving circuit 54d increases the duty ratio as the temperature indicated by the temperature signal is constant and the pressure indicated by the pressure signal is higher, that is, as the degree of superheat is lower. This reduces the lift amount of the valve body 52, and increases the degree of superheat.

Then, the driving circuit 54d applies a voltage to the micro valve Y1 via the harnesses Y6 and Y7 at the determined duty ratio. Thereby, the degree of superheat of the low-pressure refrigerant flowing out of the evaporator 6 is kept constant.

For example, when the duty ratio is zero, as described above, the third communication hole YV3 and the first communication hole YV1 communicate with each other via the micro valve Y1, and the second communication hole YV2 and the through hole Y120 of the micro valve Y1 are disconnected from each other. Therefore, as shown in fig. 13, the back pressure chamber 51m and the low-pressure refrigerant passage 51k communicate via the low-pressure introduction passage 51q and the micro valve Y1.

Therefore, the following state is established: the back pressure chamber 51m contains low-pressure refrigerant, and the front side chamber 51s contains high-pressure refrigerant from the high-pressure refrigerant passage 51 c. That is, the pressure of the refrigerant in the front side chamber 51s is higher than the pressure of the refrigerant in the back pressure chamber 51 m. As a result, the spool 52 is biased toward the back pressure chamber 51m against the force of the coil spring 53 to be extended. As a result, the throttle passage 51h has the largest opening. Therefore, the pressure difference between the high-pressure refrigerant passage 51c and the low-pressure refrigerant passage 51k is small.

In addition, for example, when the duty ratio is 100%, as described above, the second communication hole YV2 and the first communication hole YV1 communicate with each other through the micro valve Y1, and the third communication hole YV3 and the through hole Y120 of the micro valve Y1 are cut off. Therefore, as shown in fig. 14, the high-pressure refrigerant passage 51c and the back pressure chamber 51m communicate via the high-pressure introduction passage 51P and the micro valve Y1.

Therefore, the refrigerant having the same high pressure is present in both the back pressure chamber 51m and the front side chamber 51 s. As a result, the valve body 52 is biased toward the valve seat 51j by the force of the coil spring 53 to be expanded. As a result, the opening degree of the throttle passage 51h is minimized. However, the opening is greater than zero. Therefore, the pressure difference between the high-pressure refrigerant passage 51c and the low-pressure refrigerant passage 51k becomes large.

In addition, for example, in the case where the duty ratio is greater than zero and less than 100%, as already described, the second communication hole YV2 communicates with the first communication hole YV1 via the micro valve Y1, and the third communication hole YV3 communicates with the first communication hole YV1 via the micro valve Y1. As shown in fig. 11, in a range where the duty ratio is larger than the low pressure and smaller than the high pressure, the refrigerant pressure applied from the first refrigerant hole Y16 of the micro valve Y1 to the back pressure chamber 51m via the first communication hole YV1 is larger as the duty ratio is larger. Therefore, the smaller the opening of the throttle passage 51h is within a range that is larger than the minimum and smaller than the maximum, the larger the duty ratio is. Here, the low pressure refers to the pressure of the refrigerant in the low-pressure refrigerant passage 51 k. The high pressure is the pressure of the refrigerant in the high-pressure refrigerant passage 51c, and is higher than the low pressure.

In the U-turn structure of the micro valve Y1, the second outer layer Y13 is disposed closer to the valve body 52 than the first outer layer Y11. Further, a high-pressure refrigerant passage 51c and a low-pressure refrigerant passage 51k are formed in the main body 51. Therefore, compared to the case where the first outer layer Y11 is disposed closer to the valve body 52 than the second outer layer Y13, the flow path for the refrigerant flowing from the micro valve Y1 to the main body 51 can be shortened. Further, the expansion valve 5 can be miniaturized.

The autonomous unit 54 further includes: a composite sensor 54c that detects the temperature and pressure of the refrigerant flowing out from the evaporator 6; and a driving circuit 54d for controlling the temperature of the ribs Y123, Y124 based on the temperature and pressure detected by the composite sensor 54 c. By configuring in this way, the expansion valve 5 can autonomously adjust the flow rate flowing from the high-pressure refrigerant passage 51c to the low-pressure refrigerant passage 51 k.

(second embodiment)

Next, a second embodiment will be described. The present embodiment is modified to have a failure detection function in the micro valve Y1 of the first embodiment. Specifically, the micro valve Y1 includes a failure detection unit Y50 as shown in fig. 15 and 16, in addition to the same configuration as in the first embodiment.

The fault detection unit Y50 includes a bridge circuit formed on the arm Y126 of the intermediate layer Y12. The bridge circuit includes four metering resistors connected as shown in fig. 16. That is, the failure detection unit Y50 is a bridge circuit whose resistance changes according to the strain of the arm Y126 corresponding to the diaphragm. That is, the failure detection unit Y50 is a semiconductor piezoresistive strain sensor. The fault detection unit Y50 may be connected to the arm Y126 via an electrically insulating film so as not to be electrically conductive with the arm Y126.

Wirings Y51 and Y52 are connected to two input terminals located diagonally to the bridge circuit. Then, a voltage for generating a constant current is applied from the wirings Y51 and Y52 to the input terminal. The wirings Y51 and Y52 branch from the voltage (i.e., the microvalve driving voltage) applied to the microvalve Y1 via the harnesses Y6 and Y7, and extend to the two input terminals.

Further, wirings Y53 and Y54 are connected to two output terminals located at the other opposite corners of the bridge circuit. Then, voltage signals corresponding to the strain amount of the arm Y126 are output from the wirings Y53 and Y54. As described later, this voltage signal is used as information for discriminating whether the micro valve Y1 is operating normally. The voltage signals output from the wirings Y53 and Y54 are input to the driving circuit 54d.

When the drive circuit 54d obtains a voltage signal corresponding to the strain amount of the arm Y126 via the wirings Y53 and Y54, the drive circuit 54d performs a failure detection process for detecting the presence or absence of a failure of the micro valve Y1 based on the voltage signal. Examples of the failure to be detected include a failure in which the arm Y126 breaks, a failure in which a minute foreign matter is interposed between the movable portion Y128 and the first outer layer Y11 or the second outer layer Y13, and a failure in which the movable portion Y128 does not move.

When the beam Y127 and the movable portion Y128 are displaced in accordance with the expansion and contraction of the plurality of first ribs Y123 and the plurality of second ribs Y124, the strain amount of the arm Y126 changes. Therefore, the position of the movable portion Y128 can be estimated from the voltage signal corresponding to the strain amount of the arm Y126. On the other hand, if the micro valve Y1 is normal, there is also a correlation between the amount of electricity supplied from the harnesses Y6, Y7 to the micro valve Y1 and the position of the movable portion Y128. The energization amount is a control amount for controlling the micro valve Y1.

The drive circuit 54d detects the presence or absence of a failure of the micro valve Y1 by using this condition. That is, the driving circuit 54d calculates the position of the movable portion Y128 based on the first map set in advance based on the voltage signals from the wirings Y53 and Y54. Then, based on the second map set in advance, the electric power to be supplied from the harnesses Y6, Y7 to the micro valve Y1, which is required to achieve the position in the normal state, is calculated from the position of the movable portion Y128. These first map and second map are recorded in the nonvolatile memory of the drive circuit 54 d. The non-volatile memory is a non-volatile physical storage medium. The correspondence relationship of the level of the voltage signal in the first map and the position may be determined in advance by experiments or the like. The correspondence relationship between the position in the second map and the supplied power may be determined in advance by an experiment or the like.

Then, the driving circuit 54d compares the calculated electric power with electric power actually supplied from the harnesses Y6, Y7 to the micro valve Y1. If the absolute value of the difference between the former power and the latter power exceeds the allowable value, the drive circuit 54d determines that the micro valve Y1 has failed, and if the allowable value is not exceeded, the drive circuit 54d determines that the micro valve Y1 is normal. When it is determined that the micro valve Y1 has failed, the drive circuit 54d notifies the control device Y55 outside the expansion valve 5 of the failure of the micro valve Y1 via a signal line not shown.

The control device Y55 may be, for example, an air conditioning ECU that controls operations of a compressor, a blower, an air mix door, an inside/outside air switching door, and the like in the vehicle air conditioning device. Alternatively, the control device Y55 may be a meter ECU that displays the vehicle speed, the fuel remaining amount, the battery remaining amount, and the like in the vehicle. When the control device Y55 receives a notification from the drive circuit 54d that the micro valve Y1 has failed, the control device Y55 performs predetermined failure report control.

In this failure report control, the control device Y55 operates a reporting device Y56 that reports to the person in the vehicle. For example, the control device Y55 may turn on a warning lamp. The control device Y55 may cause the image display device to display an image indicating that the micro valve Y1 has failed. Thus, the occupant of the vehicle can notice the malfunction of the micro valve Y1.

In addition, the control device Y55 may record information indicating that the micro valve Y1 has failed in the storage device in the vehicle in the failure report control. The storage device is a non-volatile physical storage medium. This can keep the failure of the micro valve Y1 in the record outside the expansion valve 5.

When it is determined that the micro valve Y1 has failed, the drive circuit 54d performs energization stop control. In the energization stop control, the drive circuit 54d stops energization from the harnesses Y6, Y7 to the micro valve Y1. In this way, by stopping the energization to the micro valve Y1 at the time of the failure of the micro valve Y1, the safety at the time of the failure of the micro valve Y1 can be improved.

As described above, the failure detection unit Y50 outputs a voltage signal for discriminating whether or not the micro valve Y1 is operating normally, whereby the drive circuit 54d can easily discriminate whether or not the micro valve Y1 is failed.

The voltage signal is a signal corresponding to the strain amount of the arm Y126. Therefore, the presence or absence of a failure of the micro valve Y1 can be easily discriminated based on the relationship between the voltage signal and the amount of electricity supplied from the harnesses Y6, Y7 to the micro valve Y1.

In the present embodiment, whether or not the micro valve Y1 has failed is determined based on a change in the resistance constituting the bridge circuit. However, as another method, it is also possible to determine whether or not the micro valve Y1 has failed based on a change in the electrostatic capacitance. In this case, a plurality of electrodes are formed on the arm Y126 instead of the bridge circuit, and the plurality of electrodes form a capacitance component. A correlation exists between the deformation amount of the arm Y126 and the electrostatic capacitance between the plurality of electrodes. Therefore, the control device Y55 can determine whether or not the micro valve Y1 has failed based on the change in the electrostatic capacitance between the plurality of electrodes. The modification of the present embodiment with respect to the first embodiment can be applied to fourth to tenth embodiments described below.

(third embodiment)

Next, a third embodiment will be described. In this embodiment, a hall element 55 and a magnet 56 are added to the first embodiment. The hall element 55 and the magnet 56 are configured to detect the distance between the valve body 52 and the valve seat 51j, that is, the lift amount of the valve body 52.

The hall element 55 is fixed in the vicinity of the valve seat 51j in the main body 51. The hall element 55 is disposed so as to surround a flow path connecting the valve chamber 51g and the low-pressure refrigerant passage 51 k. The hall element 55 is electrically connected to the drive circuit 54 d. The magnet 56 is fixed to the valve seat 51j side distal end portion of the valve body 52. The magnet 56 may be a permanent magnet or an electromagnet that is energized when the drive circuit 54d is operated.

When the spool 52 moves, the magnet 56 also moves integrally therewith. Therefore, when the spool 52 moves, the hall element 55 and the magnetic field around it change. A sensor signal corresponding to the magnetic field is input from the hall element 55 to the drive circuit 54 d. The drive circuit 54d can calculate the lift amount of the spool 52 based on the sensor signal. Therefore, the hall element 55 functions as a gap sensor.

If the expansion valve 5 operates normally, there is also a correlation between the amount of electricity supplied from the harnesses Y6, Y7 to the micro valve Y1 and the amount of lift of the spool 52. The drive circuit 54d detects the presence or absence of a failure of the expansion valve 5 based on the information of the lift amount by using this condition.

Specifically, the drive circuit 54d calculates the supply power from the harnesses Y6 and Y7 to the microvalve Y1, which is required to achieve the lift amount in the normal state, based on the preset correspondence map based on the calculated lift amount. The calculated supply power is referred to as necessary supply power. The corresponding map is recorded in the nonvolatile memory of the drive circuit 54 d. The non-volatile memory is a non-volatile physical storage medium. The correspondence relationship between the amount of lift in the correspondence map and the supplied power may be determined in advance by experiments or the like.

Then, the driving circuit 54d compares the calculated necessary supply power with the power actually supplied from the harnesses Y6, Y7 to the micro valve Y1. If the absolute value of the difference between the former power and the latter power exceeds the allowable value, the drive circuit 54d determines that the expansion valve 5 has failed, and if the allowable value is not exceeded, the drive circuit 54d determines that the expansion valve 5 is normal. When it is determined that the expansion valve 5 has failed, the drive circuit 54d notifies the control device Y55 outside the expansion valve 5 of the failure of the expansion valve 5. In the present embodiment, a signal line is connected from the drive circuit 54d to the control device Y55 so that the control device Y55 can be notified from the drive circuit 54 d.

The control device Y55 may be, for example, an air conditioning ECU that controls operations of a compressor, a blower, an air mix door, an inside/outside air switching door, and the like in the vehicle air conditioning device. Alternatively, the control device Y55 may be a meter ECU that displays the vehicle speed, the fuel remaining amount, the battery remaining amount, and the like in the vehicle. When the control device Y55 receives a notification from the drive circuit 54d that the expansion valve 5 has failed, the control device Y55 performs predetermined failure report control.

In this failure report control, the control device Y55 operates a reporting device Y56 that reports to the person in the vehicle. For example, the control device Y55 may turn on a warning lamp. The control device Y55 may cause the image display device to display an image indicating that the expansion valve 5 has failed. Thereby, the occupant of the vehicle can notice the failure of the expansion valve 5.

In the failure report control, the control device Y55 may record information indicating that the expansion valve 5 has failed in a storage device in the vehicle. The storage device is a non-volatile physical storage medium. Thereby, the failure of the expansion valve 5 can be kept in the record outside the expansion valve 5.

When it is determined that the expansion valve 5 has failed, the drive circuit 54d performs energization stop control. In the energization stop control, the drive circuit 54d stops energization from the harnesses Y6, Y7 to the expansion valve 5. In this way, by stopping the energization to the micro valve Y1 at the time of the failure of the micro valve Y1, the safety at the time of the failure of the micro valve Y1 can be improved.

As described above, the hall element 55 as the gap sensor outputs a sensor signal for discriminating whether the micro valve Y1 is operating normally, whereby the drive circuit 54d can easily discriminate the presence or absence of a failure of the micro valve Y1. The modification of the present embodiment with respect to the first embodiment can be applied to fourth to tenth embodiments described below.

(fourth embodiment)

Next, a fourth embodiment will be described with reference to fig. 18 to 26. The components denoted by the same reference numerals in the present embodiment and the first embodiment have the same structure unless otherwise described below. The refrigeration cycle 1 of the present embodiment differs from the refrigeration cycle 1 of the first embodiment only in the configuration of the expansion valve 5. The configuration of the compressor 2, the condenser 3, and the receiver 4 is the same as the first embodiment.

The expansion valve 5 of the present embodiment differs from the expansion valve 5 of the first embodiment in the position, structure of the valve assembly Y0, and the like of the valve chamber 51 g. Hereinafter, a description will be given mainly of a portion of the expansion valve 5 different from the first embodiment.

As shown in fig. 18, the expansion valve 5 includes a main body 51, a valve body 52, a coil spring 53, a main body 54, a valve assembly Y0, a load adjuster 67, and the like.

The use and material of the main body 51 are the same as those of the first embodiment. The first inlet 51a, the first outlet 51b, the second inlet 51c, the second inlet 51d, the second outlet 51e, the evaporated refrigerant passage 51f, the valve chamber 51g, and the throttle passage 51h formed in the main body 51 are configured and used in the same manner as in the first embodiment. However, the valve chamber 51g accommodating the valve body 52 is not provided with a back pressure chamber having a pressure different from that of the valve chamber 51g on the throttle passage 51h side.

Hereinafter, in the expansion valve 5, the arrangement direction of the evaporated refrigerant passage 51f and the valve body 52 is referred to as the longitudinal direction, the extending direction of the evaporated refrigerant passage 51f is referred to as the width direction, and the direction orthogonal to both the longitudinal direction and the width direction is referred to as the thickness direction. In fig. 18, the up-down direction corresponds to the longitudinal direction, the left-right direction corresponds to the width direction, and the direction perpendicular to the paper surface corresponds to the thickness direction. The outer shape of the expansion valve 5 is longer in the order of the longitudinal length, the width direction length, and the thickness direction length. The same applies to the first to third embodiments.

The autonomous unit 54 includes a case 54a, a circuit board 54b, a composite sensor 54c, and a drive circuit 54d, which are similar to those of the first embodiment.

The coil spring 53 is an elastic body that biases the valve body 52 to the side closing the throttle passage 51h, as in the first embodiment. Specifically, the coil spring 53 is located on the opposite side of the valve body 52 from the evaporated refrigerant passage 51 f. The end of the coil spring 53 on the spool 52 side abuts against the spool 52 to press the spool 52, and the end opposite to the spool 52 abuts against the load adjuster 67 to press the load adjuster 67.

The load adjuster 67 is a cover member that closes the valve chamber 51g and separates the valve chamber 51g from the external space of the main body 51. A seal ring 68 is disposed between the load adjuster 67 and the main body 51. By this seal ring 68, the valve chamber 51g is sealed in a fluid-tight manner with the external space of the main body 51.

A thread and a thread groove are formed around the outer periphery of the central axis of the load adjuster 67, and a thread groove are also formed in the portion of the main body 51 into which the load adjuster 67 is fitted. Thus, the load adjuster 67 is a male screw, the main body 51 is a female screw, and the load adjuster 67 is screwed with the main body 51. Further, the center axis of the load adjuster 67 extends in the longitudinal direction (i.e., the moving direction of the spool 52) in fig. 18.

The load adjuster 67 has an operation receiving portion 67a formed on a surface thereof opposite to the valve chamber 51g and exposed to the external space of the main body 51. As shown in fig. 21, the operation receiving portion 67a has a shape surrounding a hexagonal prism-shaped hole. The operation receiving portion 67a can receive an operation by an operator or the like for adjusting the elastic force of the coil spring 53 from the outside of the main body 51.

The operation is an operation of inserting a jig such as a hexagonal spine into the hexagonal-prism-shaped hole and rotating the jig about the central axis of the load adjuster 67. By performing this operation, the load adjuster 67 moves in the direction along the central axis while rotating about the central axis as the rotation center. By the movement of the load adjuster 67, the elastic force of the coil spring 53 is adjusted.

The expansion valve 5 is formed with a communication hole 57 and a receiving hole 58 which are not shown in the first embodiment. One end of the communication hole 57 communicates with the evaporated refrigerant passage 51f, extends in the longitudinal direction, and the other end communicates with the high-pressure refrigerant passage 51 c. The portion of the communication hole 57 on the high-pressure refrigerant passage 51c side has a smaller flow path cross-sectional area than the portion of the evaporated refrigerant passage 51f side.

One end of the accommodating hole 58 communicates with the evaporated refrigerant passage 51f, extends in the longitudinal direction, and the other end communicates with the low-pressure refrigerant passage 51 k.

The expansion valve 5 further includes a coil spring 64 and a pressure transmitting portion 65. The coil spring 64 is an elastic member that is accommodated in the accommodating hole 58 in its entirety, and is movable in the longitudinal direction in the accommodating hole 58. The coil spring 64 biases the pressure transmitting portion 65 in the direction of the valve body 52. The portion of the housing hole 58 in which the coil spring 64 is disposed is a pressure chamber 58a that generates a control pressure for moving the valve body 52.

A part of the pressure transmitting portion 65 on the coil spring 64 side is accommodated in the accommodating hole 58 and abuts against the coil spring 64. The pressure transmitting portion 65 extends from a portion abutting against the coil spring 64 into the low-pressure refrigerant passage 51k through a communication portion between the housing hole 58 and the low-pressure refrigerant passage 51 k. Further, the pressure transmitting portion 65 extends from a communication portion between the low-pressure refrigerant passage 51k and the valve chamber 51g into the valve chamber 51g through the low-pressure refrigerant passage 51 k. Further, the pressure transmitting portion 65 abuts against the valve chamber 51g on the opposite side of the spool 52 from the coil spring 53. The pressure transmitting portion 65 is movable in the longitudinal direction in the housing hole 58.

With such a configuration, the pressure transmitting portion 65 receives the control pressure generated in the pressure chamber 58a and the elastic force of the coil spring 64, and transmits a force corresponding to the control pressure and the elastic force (i.e., a resultant force thereof) to the spool 52. Accordingly, the valve body 52 changes its position in the valve chamber 51g according to the control pressure of the pressure chamber 58a so as to balance the control pressure of the pressure chamber 58a, the spring force of the coil spring 64, and the spring force of the coil spring 53. Then, the opening degree of the throttle passage 51h varies according to the change in the position of the spool 52.

A seal ring 66 is fixed to the outer periphery of the pressure transmitting portion 65 so as to contact the outer periphery of the pressure transmitting portion 65 and the inner wall of the housing hole 58. By this seal ring 66, the pressure chamber 58a and the low-pressure refrigerant passage 51k are sealed at the outer periphery of the pressure transmitting portion 65.

In addition, a low-pressure communication flow path 58b that guides the refrigerant in the pressure chamber 58a to the low-pressure refrigerant passage 51k is formed in the pressure transmitting portion 65. The low-pressure communication passage 58b has one end open to the pressure chamber 58a and the other end open to the low-pressure refrigerant passage 51k, and is thereby communicated from the low-pressure communication passage 58b to the low-pressure refrigerant passage 51k.

In addition, a throttle portion 58c is formed between the pressure chamber 58a in the low-pressure communication flow path 58b and the low-pressure refrigerant passage 51k. The throttle portion 58c has a shape in which the flow path cross-sectional area decreases along the low-pressure communication flow path 58b. That is, the flow path cross-sectional area of the throttle portion 58c is smaller than the flow path cross-sectional areas of the flow paths at both ends thereof. By such a throttle 58c, a pressure difference can be generated between the front and rear sides thereof. That is, a pressure difference can be generated between the pressure chamber 58a and the low-pressure refrigerant passage 51k.

The valve assembly Y0 will be described with reference to fig. 18, 19, 20, 22, 23, and 24. The valve assembly Y0 of the present embodiment is disposed between the circuit board 54b and the valve body 52, and includes a micro valve Y1, a valve housing Y2, three O-rings 62a, 62b, and 62c, 2 harnesses Y6, Y7, and a conversion plate Y8.

The micro valve Y1 of the present embodiment is different from the first embodiment in that the shapes of the first refrigerant hole Y16, the second refrigerant hole Y17, and the third refrigerant hole Y18 are not circular but rectangular. The micro valve Y1 of the present embodiment is different from the first embodiment in the position where the first refrigerant holes Y16 are formed in the second outer layer Y13. The shape of the beam Y127 and the movable portion Y128 of the micro valve Y1 of the present embodiment is different from those of the first embodiment. Other structures of the micro valve Y1 are the same as those of the first embodiment.

The beam Y127 and the movable portion Y128 are different from the first embodiment in that, as shown in fig. 22, 23, and 24, they have a frame shape surrounding the through-hole Y120 penetrating to the front and rear surfaces of the intermediate layer Y12 together with the movable portion Y128.

The first refrigerant hole Y16 overlaps the portion surrounded by the beam Y127 of the through-hole Y120 in the stacking direction of the first outer layer Y11, the intermediate layer Y12, and the second outer layer Y13. The first refrigerant hole Y16 is disposed at a position closer to the arm Y126 than a position equidistant from the movable portion Y128 and the arm Y126. Other structures of the beam Y127 and the movable portion Y128 are the same as those of the first embodiment.

The micro valve Y1 operates in the same manner as in the first embodiment. This is because the first refrigerant hole Y16 and the through hole Y120 overlap each other in the lamination direction of the first outer layer Y11, the intermediate layer Y12, and the second outer layer Y13, regardless of the non-energized position, the maximum energized position, or any intermediate position of the movable portion Y128. The first refrigerant hole Y16 communicates with the through hole Y120 of the refrigerant chamber Y19 regardless of the position of the movable portion Y128. The communication and shut-off of the second and third refrigerant holes Y17 and Y18 are similar to those of the first embodiment.

One ends of the electric wires Y6 and Y7 are connected to the first application point Y129 and the second application point Y130 of the micro valve Y1, respectively, and are connected to the pattern printed on the circuit board 54b via the through holes Y14 and Y15, respectively, and the other ends thereof are connected to the pattern. A driving circuit 54d mounted on the circuit board 54b is connected to the pattern. Thus, electric power can be supplied from the drive circuit 54d to the micro valve Y1 through the harnesses Y6 and Y7. Since a gap exists between the micro valve Y1 and the circuit board 54b facing each other, the wiring of the harnesses Y6, Y7 is easy.

The switching plate Y8 is disposed between the micro valve Y1 and the valve housing Y2, and has flow paths Y81, Y82, Y83 penetrating to the front and rear surfaces thereof, as in the first embodiment. These flow paths Y81 and Y82 absorb the difference in the arrangement relationship between the refrigerant holes Y16 and Y17 and the arrangement relationship between the communication holes YV1 and YV 2.

One end of the flow path Y81 communicates with a first refrigerant hole Y16, and the other end communicates with a first communication hole YV1 described later. Accordingly, the first refrigerant hole Y16 communicates with the first communication hole YV1 via the flow path Y81. One end of the flow path Y82 communicates with a second refrigerant hole Y17, and the other end communicates with a second communication hole YV2 described later. Therefore, the second refrigerant hole Y17 communicates with the second communication hole YV2 via the flow path Y82. One end of the flow path Y83 communicates with the third refrigerant hole Y18, but as shown in fig. 20, the other end of the flow path Y83 is blocked by the valve housing Y2. That is, the third refrigerant hole Y18 is substantially blocked.

The valve housing Y2 is a resin housing that accommodates the micro valve Y1 and the conversion plate Y8 and absorbs the difference in linear expansion coefficient between the micro valve Y1 and the main body 51, as in the first embodiment. The valve housing Y2 includes a base portion Y20 surrounding the micro valve Y1, and columnar first and second protruding portions Y21 and Y22 protruding from the micro valve Y1. The first projection Y21 corresponds to a control pressure tube and the second projection Y22 corresponds to a low pressure tube. The base portion Y20, the first protruding portion Y21, and the second protruding portion Y22 may or may not be integrally formed.

The base portion Y20 is disposed between the case 54a and the main body 51, and is fixed by the fixing portion 63 so as to surround the opening 51t formed in the main body 51. An opening 51t is formed in the main body 51, and penetrates from a space surrounded by the case 54a to the evaporated refrigerant passage 51f.

The first protruding portion Y21 is connected to the base portion Y20 at one end and contacts the conversion plate Y8, and extends through the opening 51t and the evaporated refrigerant passage 51f, and is fitted into the accommodation hole 58 at the other end. In this way, the first protruding portion Y21 penetrates the evaporated refrigerant passage 51f from the micro valve Y1 side to the pressure chamber 58a side.

The second protruding portion Y22 is connected to the base portion Y20 at one end and contacts the conversion plate Y8, and extends through the opening 51t and the evaporated refrigerant passage 51f, and is fitted into the communication hole 57 at the other end. In this way, the second protruding portion Y22 penetrates the evaporated refrigerant passage 51f from the micro valve Y1 side to the pressure chamber 58a side. The extending directions of the first and second protruding portions Y21, Y22 intersect both the width direction and the thickness direction. More specifically, the extending directions of the first and second protruding portions Y21 and Y22 are longitudinal.

The first protruding portion Y21 and the second protruding portion Y22 are arranged in the width direction (i.e., the direction in which the refrigerant flows in the post-evaporation refrigerant passage 51 f) in the post-evaporation refrigerant passage 51 f. By this arrangement, the pressure loss of the refrigerant in the post-evaporation refrigerant passage 51f is reduced. The first protruding portion Y21 and the second protruding portion Y22 are connected to each other as one body inside the opening 51 t. Further, O-rings 62c are disposed on the outer peripheries of the first protruding portion Y21 and the second protruding portion Y22 in the opening 51 t. The O-ring 62c contacts both the outer peripheries of the first and second protruding portions Y21 and Y22 and the inner wall of the opening 51t, thereby sealing the space surrounded by the case 54a and the evaporated refrigerant passage 51 f.

An O-ring 62a is disposed on the outer periphery of the first protruding portion Y21 in the housing hole 58. The O-ring 62a contacts both the outer periphery of the first protruding portion Y21 and the inner wall of the accommodating hole 58, thereby sealing the space between the evaporated refrigerant passage 51f and the pressure chamber 58 a. In addition, an O-ring 62b is disposed on the outer periphery of the second protruding portion Y22 in the communication hole 57. The O-ring 62b contacts both the outer periphery of the second protruding portion Y22 and the inner wall of the communication hole 57, thereby sealing the space between the evaporated refrigerant passage 51f and the high-pressure refrigerant passage 51 c.

In addition, a first communication hole YV1 is formed in the first protruding portion Y21. The first communication hole YV1 corresponds to a control pressure introduction hole. The first communication hole YV1 communicates with the first refrigerant hole Y16 at a position closer to the micro valve Y1 than the post-evaporation refrigerant passage 51f, and communicates with the pressure chamber 58a at a position closer to the pressure chamber 58a than the post-evaporation refrigerant passage 51 f. By forming the first communication hole YV1 in the first protruding portion Y21 penetrating the post-evaporation refrigerant passage 51f in this way, the body shape in the thickness direction of the main body 51 can be suppressed, and the refrigerant introduced into the pressure chamber 58a can be prevented from interfering with the refrigerant flowing through the post-evaporation refrigerant passage 51 f.

In addition, a second communication hole YV2 is formed inside the second protruding portion Y22. The second communication hole YV2 corresponds to the high-pressure introduction hole. The second communication hole YV2 communicates with the second refrigerant hole Y17 at a position closer to the microvalve Y1 than the post-evaporation refrigerant passage 51f, and communicates with the high-pressure refrigerant passage 51c through the communication hole 57 at a position closer to the high-pressure refrigerant passage 51c than the post-evaporation refrigerant passage 51 f. By forming the second communication hole YV2 in the second protruding portion Y22 penetrating the post-evaporation refrigerant passage 51f in this way, the body shape in the thickness direction of the main body 51 can be suppressed, and interference between the high-pressure refrigerant and the low-pressure refrigerant flowing through the post-evaporation refrigerant passage 51f can be prevented.

By configuring the expansion valve 5 as described above, the circuit board 54b, the micro valve Y1, the first protruding portion Y21, the pressure chamber 58a, the pressure transmitting portion 65, the valve body 52, the coil spring 53, and the load adjuster 67 are aligned in this order in the longitudinal direction. The micro valve Y1, the evaporated refrigerant passage 51f, the pressure chamber 58a, the low-pressure refrigerant passage 51k, and the valve chamber 51g are also aligned in the longitudinal direction in this order.

The operation of the refrigeration cycle 1 having such a configuration will be described mainly with respect to differences from the first embodiment. The third refrigerant hole Y18 does not communicate the through hole Y120 with the other refrigerant flow path, whether or not it is open. Further, the first refrigerant hole Y16 is always open regardless of the position of the movable portion Y128, and therefore the through hole Y120 of the micro valve Y1 is always in communication with the housing hole 58 via the first communication hole YV 1.

[ non-runtime ]

First, a non-operation of the refrigeration cycle will be described. In this case, the operation, non-operation, and energization and non-energization of each device of the refrigeration cycle 1 are the same as those of the first embodiment. In this case, the second communication hole YV2 is cut off from the through hole Y120 of the micro valve Y1.

In this case, as in the first embodiment, the pressure of the refrigerant between the receiver 4 and the expansion valve 5 and the pressure of the refrigerant between the expansion valve 5 and the evaporator 6 are equal to each other. Therefore, the pressure of the refrigerant in the high-pressure refrigerant passage 51c and the pressure of the refrigerant in the low-pressure refrigerant passage 51k are also equal to each other.

In addition, since the low-pressure refrigerant passage 51k and the housing hole 58 communicate with each other via the low-pressure communication passage 58b for a long period of time, the pressure of the housing hole 58 is the same as the pressure of the low-pressure refrigerant passage 51 k. The pressure of the valve chamber 51g is the same as the pressure of the low-pressure refrigerant passage 51 k. Accordingly, due to the balance between the elastic force of the coil spring 53 and the elastic force of the coil spring 64, as shown in fig. 26, the valve body 52 contacts the valve seat 51j, and the throttle passage 51h is closed.

[ runtime ]

Next, a state in which the refrigeration cycle is operating will be described. In this case, the compressor 2 and the blower 8 are operated. Thereby, the pressure of the refrigerant in the high-pressure refrigerant passage 51c is higher than the pressure of the refrigerant in the low-pressure refrigerant passage 51 k. The combination sensor 54c and the drive circuit 54d also operate. Accordingly, the micro valve Y1 is energized from the driving circuit 54d via the harnesses Y6, Y7 as needed.

Specifically, the driving circuit 54d increases the duty ratio as the pressure indicated by the pressure signal is constant and the temperature indicated by the temperature signal, that is, as the degree of superheat is higher. This increases the lift amount of the valve body 52 and decreases the degree of superheat. The driving circuit 54d makes the duty ratio smaller as the temperature indicated by the temperature signal is constant and the pressure indicated by the pressure signal is higher, that is, as the degree of superheat is lower. This reduces the lift amount of the valve body 52, and increases the degree of superheat.

For example, when the duty ratio is increased to 100%, the second communication hole YV2 and the first communication hole YV1 communicate via the micro valve Y1. Therefore, the high-pressure refrigerant in the high-pressure refrigerant passage 51c is introduced into the micro valve Y1 through the communication hole 57, the second communication hole YV2, the flow path Y82, and the second refrigerant hole Y17. The high-pressure refrigerant is supplied from the first refrigerant hole Y16 of the micro valve Y1 to the pressure chamber 58a via the flow path Y81 and the first communication hole YV 1.

As a result, the pressure in the pressure chamber 58a becomes high, and the force transmitted to the valve body 52 via the pressure transmitting portion 65 is maximized. As a result, as shown in fig. 25, the throttle passage 51h has the largest opening degree and the largest lift amount. The pressure chamber 58a and the low-pressure refrigerant passage 51k communicate with each other via the low-pressure communication passage 58b, but since the throttle portion 58c is formed in the low-pressure communication passage 58b, the pressure difference between the pressure chamber 58a and the low-pressure refrigerant passage 51k is maintained.

In addition, for example, in the case where the duty ratio is greater than zero and less than 100%, the second communication hole YV2 and the first communication hole YV1 communicate via the micro valve Y1. However, the opening degree of the second refrigerant hole Y17 is smaller than when the duty ratio is 100%, and the larger the duty ratio is, the larger the opening degree of the second refrigerant hole Y17 is. Therefore, the smaller the pressure in the through hole Y120 of the micro valve Y1 is due to the decompression effect of the first refrigerant hole Y16, the lower the duty ratio is.

Therefore, the smaller the duty ratio, the lower the refrigerant pressure output from the first refrigerant hole Y16 of the micro valve Y1 to the pressure chamber 58a via the first communication hole YV 1. Thus, the force transmitted to the valve body 52 via the pressure transmitting portion 65 is larger than the maximum value and larger than the minimum value. The smaller the duty ratio is in the range where the opening degree and the lift amount of the throttle passage 51h are larger than the minimum and smaller than the maximum.

In addition, for example, in the case where the duty ratio is reduced to 0%, the second refrigerant hole Y17 is blocked. Then, the flow of the refrigerant from the high-pressure refrigerant passage 51c to the through-hole Y120 in the micro valve Y1 is shut off. Then, the refrigerant in the pressure chamber 58a gradually flows out to the low-pressure refrigerant passage 51k through the low-pressure communication flow path 58b, and the pressure of the refrigerant in the pressure chamber 58a decreases. Finally, the pressure of the refrigerant in the pressure chamber 58a is the same as the pressure of the low-pressure refrigerant passage 51 k. Accordingly, the force transmitted from the pressure transmitting portion 65 to the spool 52 also gradually decreases, and thus the lift amount and the opening degree of the throttle passage 51h decrease, and eventually become zero as shown in fig. 26.

Further, as described above, when the refrigeration cycle 1 is operated, in the case where the duty ratio is greater than 0 and the lift amount of the spool 52 is greater than zero, a pressure difference is generated between the pressure chamber 58a and the low-pressure refrigerant passage 51k. At this time, the refrigerant flows from the high-pressure refrigerant passage 51c to the low-pressure refrigerant passage 51k through the communication hole 57, the second communication hole YV2, the second refrigerant hole Y17, the through hole Y120, the first refrigerant hole Y16, the first communication hole YV1, the pressure chamber 58a, and the low-pressure communication flow path 58b in this order. At this time, as described above, the pressure difference between the pressure chamber 58a and the low-pressure refrigerant passage 51k continues to exist due to the decompression action of the throttle portion 58 c. However, the flow rate of such refrigerant is much smaller than the flow rate of the refrigerant flowing from the high-pressure refrigerant passage 51c to the low-pressure refrigerant passage 51k via the valve chamber 51 g.

In this way, the low-pressure communication flow path 58b guides the refrigerant flowing out of the micro valve Y1 to the high-pressure refrigerant passage 51c. Thereby, the refrigerant guided from the low-pressure communication flow path 58b to the low-pressure refrigerant passage 51k flows into the evaporator 6. Therefore, compared with the case where the refrigerant guided from the first refrigerant hole Y16 to the low pressure side does not flow into the evaporator 6, the refrigerant that does not contribute to heat exchange can be reduced. Further, the possibility of wastefully using the refrigerant is reduced, and the efficiency of the refrigeration cycle 1 is improved.

The first refrigerant hole Y16 outputs a control pressure higher than the low pressure of the low-pressure refrigerant passage 51k to the pressure chamber 58a, and the low-pressure communication flow path 58b guides the refrigerant flowing out of the first refrigerant hole Y16 to the low-pressure refrigerant passage 51k. The low-pressure communication passage 58b is provided with a throttle portion 58c having a passage cross-sectional area that decreases along the low-pressure communication passage 58 b.

In this way, the low-pressure communication passage 58b is configured to guide the refrigerant flowing out of the first refrigerant hole Y16 to the low-pressure refrigerant passage 51k, so that the third refrigerant hole Y18 of the micro valve Y1 does not need to communicate with the low-pressure communication passage. In such a configuration, the throttle 58c is formed in the low-pressure communication passage 58b, and a pressure difference can be generated between the front and rear of the throttle 58c, so that the function of the first refrigerant hole Y16, such as the output control pressure, is less likely to be impaired.

The pressure transmitting portion 65 extends from the pressure chamber 58a to the valve body 52 through the low-pressure refrigerant passage 51k, and the low-pressure communication flow path 58b is formed inside the pressure transmitting portion 65 and communicates from the pressure chamber 58a to the low-pressure refrigerant passage 51k. In this way, with the pressure transmitting portion 65 receiving the control pressure of the pressure chamber 58a and passing through the low-pressure refrigerant passage 51k, the low-pressure communication flow path 58b that communicates from the pressure chamber 58a to the low-pressure refrigerant passage 51k is formed, so that there is no need to provide a member for only the low-pressure communication flow path 58 b.

The combination sensor 54c, the micro valve Y1, and the drive circuit 54d are disposed on the opposite side of the valve body 52 with respect to the evaporated refrigerant passage 51 f. By configuring in this way, the wiring of the electric wiring between the sensor, the control valve member, and the drive circuit is facilitated.

In the main body 51, the micro valve Y1, the evaporated refrigerant passage 51f, and the pressure chamber 58a are arranged in a row in this order in the longitudinal direction. The first protruding portion Y21 serving as a control pressure pipe penetrates the evaporated refrigerant passage 51f from the micro valve Y1 side to the pressure chamber 58a side. The first protruding portion Y21 is formed with a first communication hole YV1, and the first communication hole YV1 communicates with the first refrigerant hole Y16 at a position closer to the micro valve Y1 than the post-evaporation refrigerant passage 51f and communicates with the pressure chamber 58a at a position closer to the pressure chamber 58a than the post-evaporation refrigerant passage 51 f.

With this configuration, the control pressure can be applied from the micro valve Y1 via the first communication hole YV1 formed through the first protruding portion Y21 of the post-evaporation refrigerant passage 51 f. Therefore, while maintaining the function of the micro valve Y1, the wiring between the complex sensor 54c, the micro valve Y1, and the driving circuit 54d becomes easy. Further, the body shape of the micro valve Y1 and the valve device in the thickness direction can be suppressed.

(fifth embodiment)

Next, a fifth embodiment will be described with reference to fig. 27 and 28. The refrigeration cycle 1 according to the present embodiment changes the arrangement form of the low-pressure communication passage 58b with respect to the refrigeration cycle 1 of the fourth embodiment. The other structure is the same as that of the fourth embodiment.

The low-pressure communication passage 58b of the present embodiment is not formed in the pressure transmitting portion 65, but is arranged in a form of a gap between the outer peripheral surface of the pressure transmitting portion 65 and the inner peripheral surface of the housing hole 58. The low-pressure communication passage 58b communicates with the pressure chamber 58a at one end and communicates with the low-pressure refrigerant passage 51k at the other end.

In addition, in order to communicate the low-pressure communication passage 58b with both the pressure chamber 58a and the low-pressure refrigerant passage 51k, as shown in fig. 28, a slit 66a through which the refrigerant can pass is formed in the seal ring 66. The slit 66a penetrates in the longitudinal direction (i.e., the direction orthogonal to the paper surface in fig. 28). The slit 66a is a part of the low-pressure communication passage 58b, and the passage cross-sectional area is smaller than the passage cross-sectional area of the other part of the slit 66a. Therefore, the slit 66a functions as a throttle portion that generates a pressure difference between the pressure chamber 58a and the low-pressure refrigerant passage 51 k.

The refrigeration cycle 1 according to the present embodiment is operated by replacing the low-pressure communication passage 58b and the slit 66a according to the fourth embodiment with the low-pressure communication passage 58b and the slit 66a according to the present embodiment.

As described above, the low-pressure communication flow path 58b can be provided in the gap between the inner wall surface of the housing hole 58 and the outer peripheral surface of the pressure transmitting portion 65 by the housing hole 58 including the pressure chamber 58a and communicating with the low-pressure refrigerant passage 51k and the pressure transmitting portion 65 receiving the control pressure of the pressure chamber 58a and passing through the low-pressure refrigerant passage 51k. By so doing, there is no need to provide a member for only the low-pressure communication flow path 58b. Further, since the seal ring 66 can be used as the throttle portion, the shapes of the main body 51 and the pressure transmission portion 65 do not need to be complicated in order to provide the throttle portion. In addition, in the present embodiment, the same effects as those of the fourth embodiment can be obtained from the same configuration as the fourth embodiment.

(sixth embodiment)

Next, a sixth embodiment will be described with reference to fig. 29. The refrigeration cycle 1 according to the present embodiment changes the arrangement form of the low-pressure communication passage 58b with respect to the refrigeration cycle 1 of the fourth embodiment. The other structure is the same as that of the fourth embodiment.

The low-pressure communication passage 58b of the present embodiment is formed in the main body 51 so as to bypass the pressure transmitting portion 65 from the pressure chamber 58a and communicate with the low-pressure refrigerant passage 51k, instead of being formed in the pressure transmitting portion 65. The low-pressure communication passage 58b branches from the receiving hole 58 in the pressure chamber 58a, and extends to the low-pressure refrigerant passage 51k in the main body 51.

In addition, a throttle portion 58c having a smaller flow path cross-sectional area than the flow path cross-sectional area before and after is formed between the pressure chamber 58a and the low-pressure refrigerant passage 51k in the low-pressure communication flow path 58b, as in the fourth embodiment. By such a throttle 58c, a pressure difference can be generated between the front and rear of the throttle 58c. That is, a pressure difference can be generated between the pressure chamber 58a and the low-pressure refrigerant passage 51 k. In the present embodiment, the same effects as those of the fourth embodiment can be obtained from the same configuration as the fourth embodiment.

(seventh embodiment)

Next, a seventh embodiment will be described with reference to fig. 30. The refrigeration cycle 1 according to the present embodiment differs from the refrigeration cycle 1 according to the fourth embodiment in the structure of the valve housing Y2, the structure of the switching plate Y8, the arrangement form of the low-pressure communication flow path, and the structure of the main body 51. The other structure is the same as that of the fourth embodiment. The following description focuses on differences from the fourth embodiment.

The valve housing Y2 of the present embodiment has a third protruding portion Y23 in addition to the base portion Y20, the first protruding portion Y21, the second protruding portion Y22, and the O-rings 62a, 62b, 62c, which are similar to those of the fourth embodiment. The third protruding portion Y23 corresponds to a low pressure pipe. The base portion Y20, the first protruding portion Y21, the second protruding portion Y22, and the third protruding portion Y23 may or may not be integrally formed.

The third protruding portion Y23 is connected to the base portion Y20 at one end and contacts the conversion plate Y8, and extends through the opening 51t and the evaporated refrigerant passage 51f, and is fitted into the communication hole 59 at the other end. The communication hole 59 is a hole formed in the main body 51 in the present embodiment, and has one end communicating with the evaporated refrigerant passage 51f and the other end communicating with the low-pressure refrigerant passage 51 k.

In this way, the third protruding portion Y23 penetrates the evaporated refrigerant passage 51f from the micro valve Y1 side to the pressure chamber 58a and the low-pressure refrigerant passage 51k side. The extending direction of the third protruding portion Y23 intersects both the width direction and the thickness direction, more specifically, the longitudinal direction. The first, second, and third protruding portions Y21, Y22, Y23 are arranged in the width direction (i.e., the direction in which the refrigerant flows in the post-evaporation refrigerant passage 51 f) in the post-evaporation refrigerant passage 51 f. By this arrangement, the pressure loss of the refrigerant in the post-evaporation refrigerant passage 51f is reduced.

The first, second, and third protruding portions Y21, Y22, Y23 are integrally connected to each other inside the opening 51 t. The O-ring 62c similar to that of the fourth embodiment is disposed on the outer periphery of the first, second, and third protruding portions Y21, Y22, Y23 in the opening 51 t.

An O-ring 62d is disposed on the outer periphery of the third protruding portion Y23 in the communication hole 59. The O-ring 62d contacts both the outer periphery of the third protruding portion Y23 and the inner wall of the communication hole 59, thereby sealing the space between the evaporated refrigerant passage 51f and the low-pressure refrigerant passage 51 k.

In addition, a third communication hole YV3 is formed inside the third protruding portion Y23. The third communication hole YV3 corresponds to the low pressure introduction hole. The third communication hole YV3 communicates with the third refrigerant hole Y18 on the micro valve Y1 side of the post-evaporation refrigerant passage 51f and communicates with the low-pressure refrigerant passage 51k on the low-pressure refrigerant passage 51k side of the post-evaporation refrigerant passage 51f through the communication hole 59. By forming the third communication hole YV3 in the third protruding portion Y23 penetrating the evaporated refrigerant passage 51f in this way, the body shape in the thickness direction of the main body 51 can be suppressed, and the possibility of mixing the refrigerant of the evaporated refrigerant passage 51f with the refrigerant of the low-pressure refrigerant passage 51k can be reduced. In the present embodiment, the third communication hole YV3 corresponds to a low-pressure communication flow path.

In the present embodiment, the flow path Y83 of the switching plate Y8 communicates with the third refrigerant hole Y18 at one end and communicates with the third communication hole YV3 at the other end. Thereby, communication between the third communication hole YV3 and the third refrigerant hole Y18 is achieved. Therefore, the connection relationship between the first, second, and third refrigerant holes Y16, Y17, Y18 and the first, second, and third communication holes YV1, YV2, YV3 is the same as in the first embodiment.

The micro valve Y1 of the present embodiment may be the same as the micro valve Y1 of the fourth embodiment, or may be the same as the micro valve Y1 of the first embodiment. In either case, the movable portion Y128 of the micro valve Y1 is moved in the refrigerant chamber Y19 by transmitting the displacement amplified by the amplifying portion (i.e., the arm Y126 and the beam Y127). By this movement, the opening degrees of the second refrigerant hole Y17 and the third refrigerant hole Y18 with respect to the through hole Y120 can be adjusted.

In the present embodiment, the low-pressure communication passage 58b is not formed in the pressure transmitting portion 65. Therefore, the pressure chamber 58a of the present embodiment does not communicate with the high-pressure refrigerant passage 51c and the low-pressure refrigerant passage 51k in the expansion valve 5 without passing through the micro valve Y1.

The operation of the refrigeration cycle 1 having such a configuration will be described below.

[ non-runtime ]

First, a non-operation of the refrigeration cycle will be described. In this case, the operation, non-operation, and energization and non-energization of each device of the refrigeration cycle 1 are the same as those of the first embodiment. Therefore, in this case, the third communication hole YV3 and the first communication hole YV1 communicate with each other via the micro valve Y1, and the second communication hole YV2 and the through hole Y120 of the micro valve Y1 are cut off.

In this case, as in the first embodiment, the pressure of the refrigerant between the receiver 4 and the expansion valve 5 and the pressure of the refrigerant between the expansion valve 5 and the evaporator 6 are equal to each other. Therefore, the pressure of the refrigerant in the high-pressure refrigerant passage 51c and the pressure of the refrigerant in the low-pressure refrigerant passage 51k are also equal to each other. The pressure of the valve chamber 51g is the same as the pressure of the low-pressure refrigerant passage 51 k. Accordingly, the valve body 52 contacts the valve seat 51j due to the balance between the elastic force of the coil spring 53 and the elastic force of the coil spring 64, and the throttle passage 51h is closed.

[ runtime ]

Next, a state in which the refrigeration cycle is operating will be described. In this case, the compressor 2 and the blower 8 are operated. Thereby, the pressure of the refrigerant in the high-pressure refrigerant passage 51c is higher than the pressure of the refrigerant in the low-pressure refrigerant passage 51 k. The combination sensor 54c and the drive circuit 54d also operate. Accordingly, the micro valve Y1 is energized from the driving circuit 54d via the harnesses Y6, Y7 as needed. At this time, by the same operation as in the fourth embodiment, the drive circuit 54d determines the duty ratio of the voltages applied to the harnesses Y6 and Y7 based on the obtained pressure signal and temperature signal so that the degree of superheat of the low-pressure refrigerant flowing out from the evaporator 6 becomes a predetermined constant value.

For example, when the duty ratio is 100%, the second communication hole YV2 and the first communication hole YV1 communicate with each other through the micro valve Y1, and the third communication hole YV3 and the through hole Y120 of the micro valve Y1 are cut off as in the first embodiment. Therefore, the high-pressure refrigerant in the high-pressure refrigerant passage 51c is introduced into the micro valve Y1 through the communication hole 57, the second communication hole YV2, the flow path Y82, and the second refrigerant hole Y17. The high-pressure refrigerant is supplied from the first refrigerant hole Y16 of the micro valve Y1 to the pressure chamber 58a via the flow path Y81 and the first communication hole YV 1. As a result, the pressure in the pressure chamber 58a becomes high, and the force transmitted to the valve body 52 via the pressure transmitting portion 65 is maximized. As a result, the opening degree and the lift amount of the throttle passage 51h are maximized.

In addition, for example, when the duty ratio is greater than zero and less than 100%, the second communication hole YV2 communicates with the first communication hole YV1 via the micro valve Y1, and the third communication hole YV3 communicates with the first communication hole YV1 via the micro valve Y1, as in the first embodiment. At this time, the control pressure outputted from the first refrigerant hole Y16 of the micro valve Y1 to the pressure chamber 58a is lower than the high pressure of the high pressure refrigerant passage 51c and higher than the low pressure refrigerant passage 51 k. The smaller the duty ratio is, the smaller the opening degree of the second refrigerant hole Y17 is, and the larger the opening degree of the third refrigerant hole Y18 is. Therefore, the smaller the duty ratio, the lower the control pressure output from the first refrigerant hole Y16 of the micro valve Y1 to the pressure chamber 58a due to the decompression action of the second refrigerant hole Y17 and the third refrigerant hole Y18.

Thus, the force transmitted to the valve body 52 via the pressure transmitting portion 65 is larger than the maximum value and larger than the minimum value. The smaller the duty ratio is in the range where the opening degree and the lift amount of the throttle passage 51h are larger than the minimum and smaller than the maximum. In addition, when the duty ratio is greater than zero and less than 100%, the refrigerant flows from the high-pressure refrigerant passage 51c to the low-pressure refrigerant passage 51k through the second communication hole YV2, the micro valve Y1, and the third communication hole YV3 in this order. However, the flow amount is much smaller than the amount flowing from the high-pressure refrigerant passage 51c to the low-pressure refrigerant passage 51k through the valve chamber 51 g.

In addition, for example, when the duty ratio is zero, as in the first embodiment, the third communication hole YV3 and the first communication hole YV1 communicate with each other through the micro valve Y1, and the second communication hole YV2 and the through hole Y120 of the micro valve Y1 are cut off. Therefore, the low-pressure refrigerant in the low-pressure refrigerant passage 51k is introduced into the micro valve Y1 through the communication hole 59, the third communication hole YV3, the flow path Y83, and the third refrigerant hole Y18. The low-pressure refrigerant is supplied from the first refrigerant hole Y16 of the micro valve Y1 to the pressure chamber 58a via the flow path Y81 and the first communication hole YV 1. Thereby, the pressure in the pressure chamber 58a is low, the valve body 52 contacts the valve seat 51j, and the throttle passage 51h is closed.

The third communication hole YV3 corresponding to the pressure communication flow path communicates with the low-pressure refrigerant passage 51k from the third refrigerant hole Y18 across the evaporated refrigerant passage 51 f. In the present embodiment, as in the fourth embodiment, a load adjuster 67 is provided, which is capable of receiving an operation for adjusting the elastic force of the coil spring 53 from the outside of the main body 51 and is located on the same side as the valve body 52 with respect to the evaporated refrigerant passage 51 f. The micro valve Y1 is located on the opposite side of the load adjuster 67, the spool 52, and the low-pressure refrigerant passage 51k with respect to the evaporated refrigerant passage 51f, so as to avoid interference with the load adjuster 67. In this case, by passing the third communication hole YV3 from the third refrigerant hole Y18 over the evaporated refrigerant passage 51f and communicating with the low-pressure refrigerant passage 51k, interference between the micro valve Y1 and the load adjuster 67 can be avoided, and the refrigerant can be guided from the micro valve Y1 to the low-pressure refrigerant passage 51 k.

In addition, a third communication hole YV3 as a low-pressure communication flow path is formed in the third protruding portion Y23 that penetrates the evaporated refrigerant passage 51f from the micro valve Y1 side to the low-pressure refrigerant passage 51k side. By configuring in this way, even if the evaporated refrigerant passage 51f crosses the third communication hole YV3, both are insulated in the flow path. The expansion valve 5 can be suppressed from having a body shape in the thickness direction intersecting the direction in which the evaporated refrigerant passage 51f, the pressure chamber 58a, the pressure transmitting portion 65, and the valve body 52 are arranged and intersecting the extending direction of the evaporated refrigerant passage 51 f. In addition, in the present embodiment, the same effects as those of the fourth embodiment can be obtained from the same configuration as the fourth embodiment.

(eighth embodiment)

Next, an eighth embodiment will be described with reference to fig. 31 and 32. The refrigeration cycle 1 of the present embodiment differs from the seventh embodiment in the structure of the valve housing Y2, the structure of the switching plate Y8, the arrangement form of the low-pressure communication flow path, and the structure of the main body 51. The other structure is the same as that of the seventh embodiment. The following description focuses on differences from the fourth embodiment.

The valve housing Y2 of the present embodiment is different from the valve housing Y2 of the seventh embodiment in the position and length of the third protruding portion Y23. Specifically, as shown in fig. 32, the third protruding portion Y23 is arranged in the thickness direction of the expansion valve 5 with respect to the second protruding portion Y22. The third protruding portion Y23 of the present embodiment has a shorter length in the longitudinal direction than the seventh embodiment. The length of the third communication hole YV3 formed in the third protruding portion Y23 also becomes shorter as the third protruding portion Y23 becomes shorter.

One end of the third communication hole YV3 communicates with the flow path Y83 of the switching plate Y8, and the other end communicates with the bypass flow path 58 d. As shown in fig. 32, the bypass flow path 58d is formed in the main body 51, communicates with the third communication hole YV3 at one end, extends in the longitudinal direction, and then extends in the thickness direction so as to communicate with the low-pressure refrigerant passage 51k at the other end. A sealing member 62e is attached to the main body 51 to seal the bypass passage 58d from the external space of the main body 51. The flow path constituted by the third communication hole YV3 and the bypass flow path 58d corresponds to a low-pressure communication flow path.

The low-pressure communication passage bypasses the evaporated refrigerant passage 51f from the passage Y83 in the valve housing Y2 and in the main body 51, and communicates with the low-pressure refrigerant passage 51k. That is, the low-pressure communication hole passage extends beyond the post-evaporation refrigerant passage from a position closer to the micro valve Y1 than the post-evaporation refrigerant passage 51f to a position closer to the low-pressure refrigerant passage 51k than the post-evaporation refrigerant passage 51f by being displaced in the thickness direction of the main body 51 relative to the post-evaporation refrigerant passage 51 f.

In the switching plate Y8, flow paths Y81, Y82, and Y83 are formed so that the first, second, and third refrigerant holes Y16, Y17, and Y18 of the micro valve Y1 communicate with the first, second, and third communication holes YV1, YV2, and YV3, respectively. This is the same as the seventh embodiment. In the present embodiment, the communication hole 59 is not formed.

The operation of this embodiment is the same as that of the seventh embodiment. However, when the third refrigerant hole Y18 is opened, the refrigeration cycle 1 and the low-pressure refrigerant passage 51k communicate with each other via the third refrigerant hole Y18, the third communication hole YV3, and the bypass flow path 58 d.

In this way, the low-pressure communication flow path is formed outside the evaporated refrigerant passage 51f in the main body 51 and the valve housing Y2, whereby the low-pressure communication flow path bypasses the evaporated refrigerant passage 51f from the third refrigerant hole Y18 side and communicates with the evaporated refrigerant passage 51f side. By configuring in this way, the refrigerant that has emerged from the third refrigerant hole Y18 can be guided to the low-pressure refrigerant passage 51k across the evaporated refrigerant passage 51f by using the inside or the like in the thickness direction of the main body 51. In addition, in the present embodiment, the same effects as those of the seventh embodiment can be obtained from the same configuration as the seventh embodiment.

(ninth embodiment)

Next, a ninth embodiment will be described with reference to fig. 33, 34, and 35. In the present embodiment, as shown in fig. 35, the position where the third refrigerant holes Y18 communicate is changed from the low-pressure refrigerant passage 51k to the evaporated refrigerant passage 51f, as compared with the eighth embodiment.

Specifically, the bypass passage 58d according to the eighth embodiment is discarded, and the end of the third communication hole YV3 on the opposite side to the passage Y83 communicates with the evaporated refrigerant passage 51f. In the operation of the refrigeration cycle 1, the low-pressure refrigerant passage 51k and the post-evaporation refrigerant passage 51f are at substantially the same pressure, and therefore, the same operation as in the eighth embodiment is also achieved in the present embodiment. In addition, in the present embodiment, the same effects as those of the fourth embodiment can be obtained from the same configuration as in the eighth embodiment.

(tenth embodiment)

Next, a tenth embodiment will be described with reference to fig. 36. The present embodiment is different from the fourth embodiment in the arrangement of the composite sensor 54 c. Specifically, the compound sensor 54c is formed integrally with the valve assembly Y0.

More specifically, the composite sensor 54c is sandwiched between the first protruding portion Y21 and the second protruding portion Y22 in the opening 51t, and is connected to a driving circuit 54d mounted on the circuit board 54b via a wiring not shown.

The composite sensor 54c is attached to both the first protruding portion Y21 and the second protruding portion Y22 by adhesion or the like. Thereby, sealing between the space surrounded by the case 54a and the evaporated refrigerant passage 51f is achieved between the composite sensor 54c and the first protruding portion Y21 and between the composite sensor 54c and the second protruding portion Y22.

As described above, the composite sensor 54c and the valve assembly Y0 are integrally assembled to the main body 51. By configuring in this way, the labor and the components for assembly can be reduced compared to the case where the composite sensor 54c and the micro valve Y1 are assembled as independent bodies to the main body 51. In fact, in the above-described configuration, no member for assembling the composite sensor 54c to the main body 51 is required. In addition, a hole for exposing the composite sensor 54c to the evaporated refrigerant passage 51f is not required to be provided outside the opening 51 r.

The modification of the present embodiment with respect to the fourth embodiment can be similarly applied to other embodiments. In addition, in the present embodiment, the same effects as those of the fourth embodiment can be obtained from the same configuration as the application target embodiment.

(other embodiments)

The present invention is not limited to the above-described embodiment, and can be appropriately modified. The above embodiments are not mutually independent, and can be appropriately combined except for the case where they are clearly not combined. In the above embodiments, the elements constituting the embodiments are not necessarily required, except when they are particularly clearly indicated as being required, when they are clearly understood as being required in principle, and the like. In the above embodiments, when reference is made to the number, value, amount, range, and other numerical values of the constituent elements of the embodiments, the number is not limited to a specific number except when the number is particularly and explicitly limited to the specific number in principle. In the above embodiment, when acquiring the external environment information (for example, the humidity outside the vehicle) of the vehicle from the sensor is described, the sensor may be discarded and the external environment information may be received from a server or cloud outside the vehicle. Alternatively, the sensor may be discarded, the related information related to the external environment information may be acquired from a server or cloud outside the vehicle, and the external environment information may be estimated from the acquired related information. In particular, when a plurality of values are illustrated for a certain amount, values among the plurality of values can be adopted, except for the cases described in particular and the cases where it is obviously impossible in principle. In the above embodiments, when referring to the shape, positional relationship, and the like of the constituent elements and the like, the shape, positional relationship, and the like are not limited to those described above, except for the case where they are specifically shown and the case where they are limited to specific shapes, positional relationships, and the like in principle. The present invention also allows the following modifications and equivalent-range modifications with respect to the above-described embodiments. The following modifications can be independently selected for application to and non-application from the above embodiments. That is, any combination of the following modifications can be applied to the above-described embodiments.

Modification 1

In each of the above embodiments, the plurality of first ribs Y123 and the plurality of second ribs Y124 generate heat by energization, and the temperature thereof rises due to the heat generation, thereby expanding. However, these components may also be constructed of shape memory materials that change in length as temperature changes.

Modification 2

In the fifth embodiment, when the energization from the harnesses Y6, Y7 to the micro valve Y1 is stopped, the micro valve Y1 communicates with the low-pressure refrigerant passage 51 k. However, this is not necessarily the case. For example, when the energization from the harnesses Y6 and Y7 to the micro valve Y1 is stopped, the micro valve Y1 may communicate with the high-pressure refrigerant passage 51 c.

Modification 3

In the third embodiment, the hall element 55 is used as the gap sensor, but an eddy current type sensor may be used as the gap sensor. In this case, the magnet 56 is discarded and the hall element 55 is replaced with a coil in the third embodiment. A high-frequency current flows through the coil. As a result, a high-frequency magnetic field is generated around the coil. When the position of the metal valve element 52 in the magnetic field changes, the impedance of the coil changes. The drive circuit 54d can calculate the lift amount of the spool 52 based on the conversion of the impedance.

Modification 4

The function of detecting the failure of the expansion valve 5 by the hall element 55, the magnet 56, and the driving circuit 54d using these in the third embodiment can also be applied to the second embodiment. In this case, the drive circuit 54d can detect both the failure of the expansion valve 5 and the failure of the micro valve Y1. The reporting device Y56 can report both the failure of the expansion valve 5 and the failure of the micro valve Y1.

Modification 5

In each of the above embodiments, the second refrigerant hole Y17 communicates with the high-pressure refrigerant passage 51c via the second communication hole YV2 and the high-pressure introduction path 51P. However, the second refrigerant hole Y17 may communicate with a high-pressure flow path outside the main body 51 instead of the high-pressure refrigerant path 51 c. In this case, the first passage corresponds to the external high-pressure flow path, not to the high-pressure refrigerant passage 51 c. The external high-pressure flow path may be, for example, a flow path downstream of the refrigerant flow of the receiver 4 and upstream of the refrigerant flow of the expansion valve 5.

Modification 6

In each of the above embodiments, the third refrigerant hole Y18 communicates with the low-pressure refrigerant passage 51k via the third communication hole YV3 and the low-pressure introduction path 51 q. However, the third refrigerant hole Y18 may communicate with a low-pressure flow path outside the main body 51 instead of the low-pressure refrigerant path 51 k. In this case, the second passage corresponds to the external low-pressure flow path, not to the low-pressure refrigerant passage 51 k. The external low-pressure flow path may be, for example, a flow path downstream of the expansion valve 5 and upstream of the evaporator 6.

Modification 7

In each of the above embodiments, the opening degree of the second refrigerant hole Y17 with respect to the through hole Y120 and the opening degree of the third refrigerant hole Y18 with respect to the through hole Y120 are adjusted in linkage by the movement of the movable portion Y128. However, this is not necessarily the case.

For example, the opening degree of the second refrigerant hole Y17 with respect to the through hole Y120 may be adjusted only by the movement of the movable portion Y128, and the opening degree of the third refrigerant hole Y18 with respect to the through hole Y120 may be always constant. Alternatively, for example, the opening degree of the third refrigerant hole Y18 with respect to the through hole Y120 may be adjusted only by the movement of the movable portion Y128, and the opening degree of the second refrigerant hole Y17 with respect to the through hole Y120 may be always constant. Even then, the refrigerant pressure outputted from the first refrigerant hole Y16 varies by the movement of the movable portion Y128.

Modification 8

In the above embodiments, the holes communicating with the through-hole Y120 from the outside of the micro valve Y1 are three of the first refrigerant hole Y16, the second refrigerant hole Y17, and the third refrigerant hole Y18. However, four or more refrigerant holes communicating with the through-hole Y120 from the outside of the micro valve Y1 may be used.

The opening degree of the fourth and subsequent refrigerant holes may be adjusted by the movement of the movable portion Y128, or may not be adjusted. The fourth and subsequent refrigerant holes may communicate with the back pressure chamber 51m in the same manner as the first refrigerant hole Y16. The fourth and subsequent refrigerant holes may communicate with the high-pressure refrigerant passage 51c in the same manner as the second refrigerant hole Y17. The fourth and subsequent refrigerant holes may communicate with the low-pressure refrigerant passage 51k in the same manner as the third refrigerant hole Y18. The fourth and subsequent refrigerant holes may be a flow path through which a refrigerant having a pressure different from the high pressure and the low pressure flows, and may communicate with a flow path that is not the back pressure chamber 51 m.

Modification 9

In the above embodiment, the expansion valve 5 is applied to a cooler cycle for performing air conditioning in a vehicle room in a refrigeration cycle. However, the expansion valve 5 may be used for other refrigeration cycles. For example, the present invention may be applied to a heat pump cycle for a vehicle as a flow rate adjustment valve or to a battery cooler for a vehicle as a flow rate adjustment valve. In such an application example, if the expansion valve 5 fails, the travel distance and the battery are greatly affected. Therefore, it is advantageous to notify the failure of the expansion valve 5 or the failure of the micro valve Y1 to the external in-vehicle device of the expansion valve 5.

Modification 10

In the above embodiments, the expansion valve is exemplified as a valve device for adjusting the flow rate by a valve. However, the valve device for adjusting the flow rate by moving the valve by the micro valve Y1 is not limited to the expansion valve, and may be another flow rate adjusting valve in the refrigeration cycle.

Modification 11

The shape and size of the micro valve Y1 are not limited to those shown in the above embodiment. The micro valve Y1 may have the first, second, and third refrigerant holes Y16, Y17, Y18 having such a hydraulic diameter that the flow rate can be controlled to be extremely small and that the small garbage existing in the flow path is not clogged.

Modification 12

In the above embodiment, the second communication hole YV2 communicates the second refrigerant hole Y17 with the high-pressure refrigerant passage 51 c. However, the communication destination between the second communication hole YV2 and the second refrigerant hole Y17 is not limited to the high-pressure refrigerant passage 51c, and any position may be used as long as it is a flow path through which a refrigerant having a higher pressure than the refrigerant flowing through the low-pressure refrigerant passage 51k flows.

Modification 13

In the fourth, fifth, sixth, and ninth embodiments, the control pressure is output from the first refrigerant hole Y16 to the outside of the micro valve Y1, the second refrigerant hole Y17 communicates with the high-pressure passage outside the micro valve Y1, and the third refrigerant hole Y18 is substantially closed. In other embodiments, the control pressure is output from the first refrigerant hole Y16 to the outside of the micro valve Y1, the second refrigerant hole Y17 communicates with the high-pressure passage outside the micro valve Y1, and the third refrigerant hole Y18 communicates with the low-pressure passage outside the micro valve Y1. In addition to these, there may be the following examples: the control pressure is output from the first refrigerant hole Y16 to the outside of the micro valve Y1, the second refrigerant hole Y17 is substantially closed, and the third refrigerant hole Y18 communicates with the low-pressure passage outside the micro valve Y1.

Modification 14

In the above embodiment, the high-pressure refrigerant passage 51c in the expansion valve 5 is illustrated as an example of the first passage communicating with the second refrigerant hole Y17. However, the first passage communicating with the second refrigerant hole Y17 may be located outside the expansion valve 5 as long as the first passage is a portion through which the refrigerant having a higher pressure than the low-pressure refrigerant flowing out of the expansion valve 5 flows.

Modification 15

The first communication hole YV1, the second communication hole YV2, and the third communication hole YV3 in the above embodiment are members different from the main body 51, but may be formed integrally with the main body 51.

Modification 16

In the above embodiment, the physical quantities detected by the combination sensor 54c are the pressure and temperature in the evaporated refrigerant passage 51 f. However, the physical quantity detected by the combination sensor 54c may be only the pressure in the evaporated refrigerant passage 51f or only the temperature in the evaporated refrigerant passage 51 f. The physical quantity detected by the combination sensor 54c may be other physical quantity that is not the pressure or the temperature.

Modification 17

In the fourth to 10 embodiments described above, the second communication hole YV2 is formed in the second protruding portion Y22 penetrating the inside of the evaporated refrigerant passage 51f, and thus extends from the micro valve Y1 side of the evaporated refrigerant passage 51f to the pressure chamber 58a side across the evaporated refrigerant passage 51 f. However, the second communication hole YV2 may extend beyond the evaporated refrigerant passage 51f from the micro valve Y1 side of the evaporated refrigerant passage 51f to the pressure chamber 58a side at a position offset in the thickness direction of the expansion valve 5 with respect to the evaporated refrigerant passage 51 f.

(summary)

According to a first aspect shown in some or all of the above embodiments, a valve device for a refrigeration cycle includes: a main body having an inflow port, an outflow port, and a valve chamber through which a refrigerant flowing from the inflow port to the outflow port flows; a valve body that is displaced in the valve chamber to adjust a flow rate of the refrigerant flowing from the inflow port to the outflow port through the valve chamber; and a control valve member that changes a pressure acting on a pressure chamber that generates a control pressure for moving the valve element, the control valve member including: a base portion formed with a refrigerant chamber through which a refrigerant flows, a first refrigerant hole that communicates with the refrigerant chamber and with the pressure chamber, and a second refrigerant hole that communicates with the refrigerant chamber and with a passage of the refrigerant outside the control valve member; a driving unit that displaces when the temperature of the driving unit itself changes; an amplifying unit that amplifies a displacement of the driving unit due to a change in temperature; and a movable portion that moves in the refrigerant chamber by transmitting the displacement amplified by the amplifying portion, thereby adjusting the opening degree of the second refrigerant hole with respect to the refrigerant chamber, wherein when the driving portion is displaced due to a change in temperature, the driving portion applies a force to the amplifying portion at a force application position, so that the amplifying portion is displaced with a hinge as a fulcrum, and the amplifying portion applies a force to the movable portion at a connection position between the amplifying portion and the movable portion, and a distance from the hinge to the connection position is longer than a distance from the hinge to the force application position.

In addition, according to a second aspect, the pressure chamber is the valve chamber, the passage communicating with the second refrigerant hole is a first passage through which high-pressure refrigerant flows, a third refrigerant hole communicating with a second passage through which low-pressure refrigerant lower than the high pressure flows and communicating with the refrigerant chamber is formed in the base portion, and the movable portion is moved in the refrigerant chamber by transmitting displacement amplified by the amplifying portion, whereby at least one of an opening degree of the second refrigerant hole with respect to the refrigerant chamber and an opening degree of the third refrigerant hole with respect to the refrigerant chamber is adjusted. Thus, the valve member communicates with the low pressure without passing through the flow path that outputs the control pressure.

In addition, according to a third aspect, the base portion includes a first outer layer having a plate shape, a second outer layer having a plate shape, and a fixing portion that is sandwiched and fixed between the first outer layer and the second outer layer, and the first refrigerant hole, the second refrigerant hole, and the third refrigerant hole are formed in the second outer layer. By configuring in this way, the flow path in the control valve member has a U-turn configuration.

In accordance with a fourth aspect, the second outer layer is disposed closer to the valve body than the first outer layer, and the first passage and the second passage are formed in the main body. By configuring in this way, the flow path through which the refrigerant flows from the control valve member to the main body can be shortened as compared with the case where the first outer layer is disposed on the side of the valve body closer to the second outer layer. Furthermore, the valve device can be miniaturized.

In addition, according to a fifth aspect, a hole is formed in the first outer layer for passing a wire harness for changing the temperature of the driving portion. In this way, the flow path of the control valve member has a U-turn structure, and a hole through which the harness passes is formed in the first outer layer on the side opposite to the first refrigerant hole side. Moreover, the second outer layer is closer to the spool than the first outer layer. Therefore, the harness can be placed on the side closer to the atmosphere than the flow path or the like of the refrigerant on the first refrigerant hole side. Therefore, the necessity of a sealing structure such as an airtight portion for reducing the influence of the refrigerant atmosphere on the electric wiring is reduced.

Further, according to the sixth aspect, the movable portion is controlled to a first position that fully closes the second refrigerant hole with respect to the refrigerant chamber and fully opens the third refrigerant hole with respect to the refrigerant chamber, a second position that fully opens the second refrigerant hole with respect to the refrigerant chamber and fully closes the third refrigerant hole with respect to the refrigerant chamber, and an intermediate position that opens the second refrigerant hole with respect to the refrigerant chamber at an intermediate opening degree between fully closed and fully open, and opens the third refrigerant hole with respect to the refrigerant chamber at an intermediate opening degree between fully closed and fully open. By configuring in this way, the refrigerant pressure output from the first refrigerant hole can be adjusted in a wide range between the high pressure introduced from the second refrigerant hole and the low pressure introduced from the third refrigerant hole.

In addition, according to a seventh aspect, the valve device is an expansion valve for decompressing and expanding a refrigerant on a refrigerant flow upstream side of an evaporator in the refrigeration cycle, the valve device includes an autonomous portion fixed to the main body, the autonomous portion having: a composite sensor that detects a temperature and a pressure of the refrigerant flowing out from the evaporator; and a drive circuit that controls the temperature of the drive section based on the temperature and the pressure detected by the composite sensor. By configuring in this way, the valve device can autonomously adjust the flow rate.

In addition, according to an eighth aspect, the valve device includes a gap sensor that is fixed to the main body and detects a lift amount of the valve body. By providing such a gap sensor, information for determining the presence or absence of a failure of the valve device can be obtained.

In addition, according to a ninth aspect, the control valve member is provided with a failure detection unit that outputs a signal for discriminating whether the control valve member is operating normally or has failed. By outputting such a signal from the control valve member, the presence or absence of a failure of the control valve member can be easily distinguished.

In addition, according to a tenth aspect, the signal is a signal corresponding to a strain amount of the amplifying section. By configuring as described above, the presence or absence of a failure of the valve device can be discriminated based on the relationship between the signal and the control amount for controlling the control valve member.

In addition, according to an eleventh aspect, the driving unit generates heat by energization, and the failure detecting unit outputs the signal to a device that stops energization of the control valve member when the control valve member fails. In this way, by stopping the energization at the time of failure of the control valve member, the safety at the time of failure can be improved.

In addition, according to a twelfth aspect, the valve device includes a circuit that is capable of notifying a control device that controls a reporting device that reports to a person, the circuit receives the signal from the failure detection unit, determines whether the control valve member is operating normally or has failed based on the signal, and notifies the control device based on the determination that the failure has occurred, so that the reporting device reports that the control valve member has failed. Thus, a person can know the failure of the control valve member.

In addition, according to a thirteenth aspect, the control valve member is constituted by a semiconductor chip. Therefore, the control valve member can be made compact.

In addition, according to a fourteenth aspect, the valve device is an expansion valve for decompressing the refrigerant, the passage communicating with the second refrigerant hole is a first passage through which the high-pressure refrigerant before being decompressed by the expansion valve flows, the refrigerant condensed by a condenser for condensing the refrigerant flows into the inflow port in the refrigeration cycle, the refrigerant flowing in from the inflow port is decompressed to a lower pressure than the high-pressure refrigerant by passing through a throttle passage formed between the valve body and a valve seat, the refrigerant decompressed by the throttle passage passes through a second passage and thereafter flows out from the outflow port communicating with an inlet side of an evaporator for evaporating the refrigerant in the refrigeration cycle, and the valve device is provided with a low-pressure communication passage for guiding the refrigerant in the refrigerant chamber to the second passage.

In this way, the low-pressure communication flow path guides the refrigerant in the refrigerant chamber to the second passage, and the refrigerant guided to the second passage flows into the evaporator. Therefore, compared with a case where the refrigerant guided from the refrigerant chamber to the low pressure side does not flow into the evaporator, the refrigerant that does not contribute to heat exchange can be reduced. Further, the possibility of wastefully using the refrigerant is reduced, and the efficiency of the refrigeration cycle is improved.

In addition, according to a fifteenth aspect, the first refrigerant hole outputs a control pressure higher than a low pressure of the second passage to the pressure chamber, the low pressure communication passage is formed so as to guide the refrigerant flowing out of the first refrigerant hole to the second passage, and a throttle portion having a passage cross-sectional area that decreases along the low pressure communication passage is provided in the low pressure communication passage.

In this way, the low-pressure communication flow path is configured to guide the refrigerant flowing out of the first refrigerant hole to the second passage, and thus, it is not necessary to provide a refrigerant hole different from both the first refrigerant hole and the second refrigerant hole in the control valve member and to communicate the refrigerant hole with the low-pressure communication flow path. In such a configuration, since the throttle portion is formed in the low-pressure communication flow path, a pressure difference can be generated between the front and rear of the throttle portion, and therefore, the function of the first refrigerant hole, such as the output control pressure, is less likely to be impaired.

In addition, according to a sixteenth aspect, the valve body is provided with a movable pressure transmission portion that receives the control pressure generated in the pressure chamber and transmits a force corresponding to the control pressure to the valve body, the pressure transmission portion extends from the pressure chamber to the valve body through the second passage, and the low-pressure communication flow path is formed inside the pressure transmission portion and communicates from the pressure chamber to the second passage. In this way, the low-pressure communication passage that communicates from the pressure chamber to the second passage is formed by the pressure transmitting portion receiving the control pressure of the pressure chamber and passing through the second passage, so that it is unnecessary to provide a member for only the low-pressure communication passage.

In addition, according to a seventeenth aspect, the valve body is provided with a movable pressure transmission portion that receives the control pressure generated in the pressure chamber and transmits a force corresponding to the control pressure to the valve body, the main body is formed with a housing hole that houses the pressure transmission portion, the housing hole includes the pressure chamber and communicates with the second passage, the pressure transmission portion extends to the valve body through the housing hole and the second passage, and the low-pressure communication passage is provided as a gap between an inner peripheral surface of the housing hole and the pressure transmission portion.

In this way, the low-pressure communication flow path can be provided in the gap between the inner peripheral surface of the housing hole and the outer peripheral surface of the pressure transmitting portion by the housing hole including the pressure chamber and communicating with the second passage, or by the pressure transmitting portion receiving the control pressure of the pressure chamber and passing through the second passage. By so doing, there is no need to provide a member for only the low-pressure communication flow path.

In addition, according to an eighteenth aspect, the passage communicating with the second refrigerant hole is a first passage through which a high-pressure refrigerant flows, a third refrigerant hole is formed in the base portion, the third refrigerant hole communicates with the second passage through which a low-pressure flow lower than the high-pressure flow passes and communicates with the refrigerant chamber, and the movable portion is moved in the refrigerant chamber by transmitting a displacement amplified by the amplifying portion, whereby at least one of an opening degree of the second refrigerant hole with respect to the refrigerant chamber and an opening degree of the third refrigerant hole with respect to the refrigerant chamber is adjusted.

By this arrangement, the possibility of wastefully using the refrigerant in the control valve member having the third refrigerant hole and capable of adjusting the control pressure by the opening degree adjustment is reduced, and the efficiency of the refrigeration cycle is improved.

In addition, according to a nineteenth aspect, the inflow port is a first inflow port, the outflow port is a first outflow port, the refrigeration cycle includes a compressor that compresses a refrigerant evaporated by the evaporator, and the main body is formed with: a second inlet through which the low-pressure refrigerant flowing out of the evaporator flows; a second outlet port through which the refrigerant flows out to a suction side of the compressor; and an evaporated refrigerant passage extending from the second inlet to the second outlet, the valve device including: a movable pressure transmission unit that transmits a force corresponding to the pressure of the refrigerant in the pressure chamber to the valve element; an elastic body that urges the valve body with elastic force from a side opposite to the pressure transmission portion; and an adjustment unit that adjusts the elastic force of the elastic body, wherein the main body is provided with the evaporated refrigerant passage, the pressure chamber, the pressure transmission unit, the valve body, the elastic body, and the adjustment unit in this order, the second passage is provided on one side of the valve body with respect to the evaporated refrigerant passage, and the adjustment unit is provided with an operation receiving unit that is exposed to the outside of the main body on the side opposite to the valve body, and the operation receiving unit is capable of receiving an operation for adjusting the elastic force of the elastic body from the outside of the main body, and the low-pressure communication flow path is communicated with the second passage across the evaporated refrigerant passage from the third refrigerant hole.

In this way, the control valve member is located on the opposite side of the adjustment portion, the valve body, and the second passage with respect to the evaporated refrigerant passage so as to avoid interference with the adjustment portion, and the adjustment portion is capable of receiving an operation for adjusting the elastic force of the elastic body from the outside of the main body and is located on the same side of the valve body with respect to the evaporated refrigerant passage. In this case, the low-pressure communication passage is made to communicate with the second passage across the evaporated refrigerant passage from the third refrigerant hole, so that the control valve member and the adjustment portion can be prevented from interfering with each other, and the refrigerant can be guided from the control valve member to the second passage.

In addition, according to a twentieth aspect, the refrigerant passage after evaporation is provided with a low-pressure pipe that penetrates the control valve member to the second passage side, and the low-pressure communication passage is formed inside the low-pressure pipe. By configuring in this way, even if the evaporated refrigerant passage intersects the low-pressure communication passage, both are insulated in the passage. Further, the valve device can be suppressed from being formed in a direction intersecting the direction in which the evaporated refrigerant passage, the pressure chamber, the pressure transmitting portion, and the valve element are arranged and intersecting the extending direction of the evaporated refrigerant passage.

In addition, according to a twenty-first aspect, the low-pressure communication flow path is formed outside the evaporated refrigerant passage in the main body, thereby bypassing the evaporated refrigerant passage from the third refrigerant hole and communicating with the second passage. By configuring in this way, the refrigerant exiting from the third refrigerant hole can be guided to the second passage across the evaporated refrigerant passage by utilizing the inside of the main body in the direction intersecting the direction in which the evaporated refrigerant passage, the pressure chamber, the pressure transmitting portion, and the valve element are arranged and intersecting the extending direction of the evaporated refrigerant passage.

In addition, according to a twenty-second aspect, the refrigeration cycle includes a compressor that compresses a refrigerant evaporated by an evaporator that evaporates the refrigerant in the refrigeration cycle, the valve device is an expansion valve that decompresses the refrigerant, the inflow port is a first inflow port, the outflow port is a first outflow port, the passage that communicates with the second refrigerant hole is a first passage through which a high-pressure refrigerant before being decompressed by the expansion valve flows, the refrigerant condensed by a condenser that condenses the refrigerant in the refrigeration cycle flows into the first inflow port, a throttle passage formed between the valve body and a valve seat passes through the refrigerant that flows in from the first inflow port, the refrigerant is decompressed to a lower pressure than the high-pressure refrigerant, the refrigerant that has passed through the throttle passage, the decompressed refrigerant passes through a second passage, and thereafter flows out from the first outflow port, the first outflow port communicates with an inlet side of the evaporator, and the main body is formed with: a second inlet through which the low-pressure refrigerant flowing out of the evaporator flows; a second outlet port through which the refrigerant flows out to a suction side of the compressor; and an evaporated refrigerant passage extending from the second inlet to the second outlet, the valve device including: a sensor that outputs a signal corresponding to a physical quantity regarding the refrigerant passing through the post-evaporation refrigerant passage; and a drive circuit that controls operation of the control valve member based on the signal output from the sensor, wherein the sensor, the control valve member, and the drive circuit are disposed on a side opposite to the valve element with respect to the evaporated refrigerant passage. By configuring in this way, the wiring of the electric wiring between the sensor, the control valve member, and the drive circuit is facilitated.

In a twenty-third aspect, in the main body, the control valve member, the evaporated refrigerant passage, and the pressure chamber are arranged in this order, and the valve device includes: a control pressure pipe that penetrates the evaporated refrigerant passage from the control valve member side to the pressure chamber side; and a movable pressure transmission unit that transmits a force corresponding to the pressure of the refrigerant in the pressure chamber to the valve element, wherein a control pressure introduction hole is formed in the control pressure pipe, the control pressure introduction hole being in communication with the first refrigerant hole at a position closer to the control valve member than the post-evaporation refrigerant passage and with the pressure chamber than the post-evaporation refrigerant passage.

With this configuration, the control pressure can be applied from the control valve member through the control pressure introduction hole formed in the control pressure pipe penetrating the evaporated refrigerant passage. Therefore, the processing of the electric wiring between the sensor, the control valve member, and the drive circuit becomes easy while also maintaining the function of the control valve member. Further, the body shape of the valve device in the direction intersecting the direction in which the control valve member, the evaporated refrigerant passage, and the pressure chamber are arranged and intersecting the extending direction of the evaporated refrigerant passage can be suppressed.

In addition, according to a twenty-fourth aspect, the sensor and the control valve member are integrally assembled to the main body. By configuring in this way, the labor and the parts for assembly can be reduced compared to the case where the sensor and the control valve member are assembled to the main body as separate bodies.

Claims

1. A valve device for use in a refrigeration cycle, which functions as an expansion valve for decompressing a refrigerant, comprising:

the control valve member has:

the distance from the hinge to the connection position is longer than the distance from the hinge to the force application position,

the passage communicating with the second refrigerant hole is a first passage through which a high-pressure refrigerant before being depressurized by the expansion valve flows,

in the refrigeration cycle, the refrigerant condensed by the condenser that condenses the refrigerant flows into the inflow port,

the refrigerant flowing in from the inflow port is depressurized to a lower pressure than the high-pressure refrigerant by passing through a throttle passage formed between the valve body and the valve seat, the refrigerant depressurized by passing through the throttle passage passes through a second passage and then flows out from the outflow port,

The outflow port communicates with an inlet side of an evaporator that evaporates a refrigerant in the refrigeration cycle,

the valve device is provided with a low-pressure communication flow path that guides the refrigerant in the refrigerant chamber to the second passage when the valve body is adjusted to a position where the refrigerant flows from the inlet port to the outlet port.

2. A valve device according to claim 1, wherein,

the first refrigerant hole outputs a control pressure higher than the low pressure of the second passage to the pressure chamber,

the low-pressure communication passage is formed so as to guide the refrigerant flowing out of the first refrigerant hole to the second passage, and a throttle portion having a passage cross-sectional area that decreases along the low-pressure communication passage is provided in the low-pressure communication passage.

3. A valve device according to claim 2, wherein,

a movable pressure transmission unit that receives the control pressure generated in the pressure chamber and transmits a force corresponding to the control pressure to the valve element,

the pressure transmitting portion extends from the pressure chamber to the spool through the second passage,

the low-pressure communication flow path is formed inside the pressure transmitting portion and communicates from the pressure chamber to the second passage.

4. A valve device according to claim 2, wherein,

the main body is provided with a receiving hole for receiving the pressure transmission part,

the receiving hole includes the pressure chamber and communicates with the second passage,

the pressure transmitting portion extends to the valve body through the receiving hole and the second passage,

the low-pressure communication flow path is provided as a gap between the inner peripheral surface of the housing hole and the pressure transmitting portion.

5. A valve device according to claim 1, wherein,

a third refrigerant hole that communicates with the second passage through the low-pressure communication flow path and that communicates with the refrigerant chamber,

the movable portion is moved in the refrigerant chamber by transmitting the displacement amplified by the amplifying portion, and thereby adjusts at least one of the opening degree of the second refrigerant hole with respect to the refrigerant chamber and the opening degree of the third refrigerant hole with respect to the refrigerant chamber.

6. A valve device according to claim 5, wherein,

the inflow opening is a first inflow opening,

the outflow opening is a first outflow opening,

the refrigeration cycle includes a compressor that compresses the refrigerant evaporated by the evaporator,

the main body is formed with: a second inlet through which the low-pressure refrigerant flowing out of the evaporator flows; a second outlet port through which the refrigerant flows out to a suction side of the compressor; and an evaporated refrigerant passage that reaches the second outlet port from the second inlet port,

the valve device is provided with: a movable pressure transmission unit that transmits a force corresponding to the pressure of the refrigerant in the pressure chamber to the valve element; an elastic body that urges the valve body with elastic force from a side opposite to the pressure transmission portion; and an adjusting part for adjusting the elastic force of the elastic body,

in the main body, the evaporated refrigerant passage, the pressure chamber, the pressure transmitting portion, the valve body, the elastic body, and the adjusting portion are arranged in this order, the second passage is arranged on one side of the valve body with respect to the evaporated refrigerant passage,

An operation receiving portion is formed in the adjustment portion, and is exposed to the outside of the main body on the opposite side of the valve body,

the operation receiving portion is capable of receiving an operation for adjusting the elastic force of the elastic body from the outside of the main body,

the low-pressure communication flow path communicates with the second passage from the third refrigerant hole across the evaporated refrigerant passage.

7. A valve device according to claim 6, wherein,

the control valve member is provided with a low-pressure pipe which penetrates the evaporated refrigerant passage from the control valve member side to the second passage side,

the low-pressure communication flow path is formed inside the low-pressure pipe.

8. A valve device according to claim 6, wherein,

the low-pressure communication flow path is formed outside the evaporated refrigerant passage in the main body, thereby bypassing the evaporated refrigerant passage from the third refrigerant hole and communicating with the second passage.

9. A valve device according to any one of claims 1 to 8, characterized in that,

the refrigeration cycle includes a compressor that compresses a refrigerant evaporated by an evaporator that evaporates the refrigerant in the refrigeration cycle,

The inflow opening is a first inflow opening,

the outflow opening is a first outflow opening,

the valve device is provided with: a sensor that outputs a signal corresponding to a physical quantity regarding the refrigerant passing through the post-evaporation refrigerant passage; and a drive circuit that controls the operation of the control valve member based on the signal output from the sensor,

the sensor, the control valve member, and the drive circuit are disposed on the opposite side of the valve element with respect to the evaporated refrigerant passage.

10. A valve device according to claim 9, wherein,

in the main body, the control valve member, the evaporated refrigerant passage, and the pressure chamber are arranged in this order,

the valve device is provided with: a control pressure pipe that penetrates the evaporated refrigerant passage from the control valve member side to the pressure chamber side; and a movable pressure transmitting portion that transmits a force corresponding to a pressure of the refrigerant in the pressure chamber to the valve element,

The control pressure pipe is formed with a control pressure introduction hole that communicates with the first refrigerant hole at a position closer to the control valve member than the post-evaporation refrigerant passage, and communicates with the pressure chamber at a position closer to the pressure chamber than the post-evaporation refrigerant passage.

11. A valve device according to claim 9, wherein,

the sensor and the control valve member are integrally assembled to the main body.

12. A valve device according to any one of claims 1 to 8, characterized in that,

the pressure chamber is the valve chamber,

a third refrigerant hole is formed in the base portion, the third refrigerant hole being in communication with the second passage and with the refrigerant chamber,

13. A valve device according to claim 12, wherein,

the base has a first outer layer in the shape of a plate, a second outer layer in the shape of a plate, and a fixing portion fixed by being sandwiched between the first outer layer and the second outer layer,

The first, second, and third refrigerant holes are formed in the second outer layer.

14. A valve device according to claim 13, wherein,

the second outer layer is arranged on one side closer to the valve core than the first outer layer,

the first passage and the second passage are formed in the body.

15. A valve device according to claim 13, wherein,

a hole is formed in the first outer layer for passing a harness for changing the temperature of the driving portion.

16. A valve device according to claim 12, wherein,

the movable portion is controlled to a first position that fully closes the second refrigerant hole with respect to the refrigerant chamber and fully opens the third refrigerant hole with respect to the refrigerant chamber, a second position, and an intermediate position; the second position fully opens the second refrigerant orifice with respect to the refrigerant chamber and fully closes the third refrigerant orifice with respect to the refrigerant chamber; the intermediate position opens the second refrigerant hole at an intermediate opening degree between the full closure and the full opening with respect to the refrigerant chamber, and opens the third refrigerant hole at an intermediate opening degree between the full closure and the full opening with respect to the refrigerant chamber.

17. A valve device according to any one of claims 1 to 8, characterized in that,

the valve body is provided with a gap sensor which is fixed to the body and detects the lift amount of the valve body.

18. A valve device according to any one of claims 1 to 8, characterized in that,

the valve means is an expansion valve for decompressing and expanding the refrigerant on the upstream side of the refrigerant flow of the evaporator,

the valve device comprises an autonomous part fixed to the main body,

the autonomous unit has: a composite sensor that detects a temperature and a pressure of the refrigerant flowing out from the evaporator; and a drive circuit that controls the temperature of the drive section based on the temperature and the pressure detected by the composite sensor.

19. A valve device according to any one of claims 1 to 8, characterized in that,

the control valve member includes a failure detection unit that outputs a signal for discriminating whether the control valve member is operating normally or has failed.

20. A valve device according to claim 19, wherein,

the signal is a signal corresponding to a strain amount of the amplifying section.

21. A valve device according to claim 19, wherein,

the driving part generates heat by being electrified,

the failure detection unit outputs the signal to a device that stops energization of the control valve member when the control valve member fails.

22. A valve device according to claim 19, wherein,

comprising a circuit for notifying a control device for controlling a reporting device for reporting to a person,

the circuit receives the signal from the failure detection unit, determines whether the control valve member is operating normally or has failed based on the signal, and notifies the control device based on the determination that a failure has occurred, so that the reporting device reports that the control valve member has failed.

23. A valve device according to any one of claims 1 to 8, characterized in that,

the control valve member is constituted by a semiconductor chip.