JP7015769B2 - Thermal expansion valve and refrigeration cycle system equipped with it - Google Patents

Description

The present invention relates to a temperature expansion valve and a refrigeration cycle system including the same.

In the refrigeration cycle system mounted on the vehicle, a thermal expansion valve is used in which the amount of refrigerant passing through is controlled according to the temperature change of the refrigerant discharged from the outlet of the evaporator. Such a temperature type expansion valve is, for example, as shown in Patent Document 1, a valve body made of an aluminum alloy, and the temperature of a refrigerant which is attached to the upper part of the valve body and passes through a return passage in the valve body, which will be described later. It is configured to include a valve body mechanism drive unit (referred to as a power element in Patent Document 1) that drives a valve body mechanism described later in response to a change.

The valve body communicates with the inlet port and the valve chamber to which the high-pressure refrigerant from the condenser is supplied, the valve hole (orifice) in the valve chamber, and the outlet port, and passes through a portion having a diameter smaller than the outlet port (narrowed portion). An outlet port where the discharged refrigerant is discharged toward the inlet of the evaporator, a return passage where the refrigerant discharged from the outlet of the evaporator is supplied and passed, and then returned to the compressor, and a refrigerant passing through the above-mentioned valve hole. It is equipped with a valve body mechanism that controls the flow rate of the water.

A coil spring is provided in the valve chamber to urge the valve body to be fixed to the support member in the direction of closing the valve hole of the valve seat (periphery of one open end of the valve hole).

The valve body mechanism consists of a valve body that is arranged on the valve seat and opens and closes one open end of the valve hole, and one end of the valve body that is inserted into the above-mentioned valve hole and abuts on the valve body, and the other end of the valve body mechanism drive unit described later. It is composed of a valve rod that comes into contact with the receiving portion of the stopper member. The valve stem extends toward the valve body in the valve chamber so as to cross the return passage and the stenosis described above. The return passage is located directly below the valve body mechanism drive unit and is formed between the outlet port and the inlet port in the valve body and the valve body mechanism drive unit. The cross-sectional area of the return passage is large compared to the cross-sectional area of the exit port.

The valve body mechanism drive unit can move into the diaphragm formed by the upper lid member and the receiving member, the pressure operating chamber formed between the diaphragm and the upper lid member and filled with the working gas, and the receiving member. It is equipped with a stopper member that is supported by.

In such a configuration, when the high pressure refrigerant from the condenser is supplied to the inlet port of the valve body and passes through the valve chamber, the valve hole in the valve chamber and the constriction, the refrigerant discharged from the outlet of the evaporator is the valve. When passing through the return passage of the main body, a part of the refrigerant flows into the lower surface side of the diaphragm through the opening, so that the pressure in the pressure working chamber changes according to the temperature change of the refrigerant, so that the diaphragm passes through the valve rod. The valve body will be close to or separated from the valve seat. As a result, the flow rate of the refrigerant decompressed by the orifice of the thermal expansion valve is controlled based on the temperature change of the refrigerant discharged from the outlet of the evaporator.

Japanese Unexamined Patent Publication No. 2018-25331

When the temperature type expansion valve as described above is arranged in the engine room of the vehicle, it is desired to reduce the size of the temperature type expansion valve. In addition, when the superheat degree control is performed in which the opening degree of the orifice of the thermal expansion valve is controlled so that the superheat degree of the evaporator becomes the target value, the thermal expansion valve is used to change the temperature of the refrigerant at the outlet of the evaporator. It is desirable to have a function to detect the temperature more accurately.

However, the temperature type expansion valve shown in Patent Document 1 is provided with a return passage having a cross-sectional area larger than the cross-sectional area of the outlet port inside the valve body, so that the valve body of the temperature-type expansion valve can be increased in size. Invite.

In consideration of the above problems, the present invention is a temperature-type expansion valve and a refrigeration cycle system including the temperature-type expansion valve, and the valve body of the temperature-type expansion valve can be miniaturized. It is an object of the present invention to provide a temperature type expansion valve capable of more accurately detecting a temperature change of a refrigerant at an outlet, and a refrigeration cycle system equipped with the valve.

In order to achieve the above object, the temperature type expansion valve according to the present invention is arranged in a pipe for supplying the refrigerant to the evaporator, and has a valve body having a flow path for guiding the refrigerant and a valve seat formed in the flow path. It is arranged in the valve body so as to be close to or separated from the valve port of the valve body and controls the opening area of the valve port, and is arranged at the end of the valve body separated from the flow path and formed by the diaphragm and the outer member. Operating pressure is provided with a valve body mechanism drive unit that drives the valve body mechanism via a connecting pin connected to the diaphragm according to the pressure in the chamber, and the outer member of the valve body mechanism drive unit is a thin metal plate. It is a temperature-sensitive portion formed by a portion, and has a temperature-sensitive portion that conducts heat from the outer peripheral portion of the pipe connected to the outlet of the evaporator or the peripheral portion of the outlet of the evaporator into the operating pressure chamber. The temperature sensing portion is formed between the outer peripheral portion of the pipe and the working pressure chamber, and is directly fixed to the recess where the outer peripheral portion of the pipe is received by the peripheral edge of the thin wall or the flat portion around the outlet of the evaporator. It is characterized by having a flat portion .

The thermal resistance value of the temperature-sensitive portion may be smaller than the thermal resistance value of other portions of the outer member. In such a case, the thickness of the temperature-sensitive portion may be smaller than the thickness of the other portion of the outer member, or the thermal conductivity of the temperature-sensitive portion may be smaller than that of the other portion of the outer member. It may be large compared to the thermal conductivity.

The valve body mechanism drive unit may further include an urging spring that urges the connecting pin to the diaphragm.

The refrigeration cycle system according to the present invention includes an evaporator, a compressor, and a condenser, and the above-mentioned temperature expansion valve is provided in a pipe arranged between the outlet of the condenser and the inlet of the evaporator. It is characterized by being provided.

According to the temperature type expansion valve according to the present invention and the refrigerating cycle system including the same, it is arranged at an end of the valve body separated from the flow path, and corresponds to the pressure in the working pressure chamber formed by the diaphragm and the outer member. A valve body mechanism drive unit for driving the valve body mechanism via a connecting pin connected to the diaphragm is provided, and the outer member of the valve body mechanism drive unit is the outer peripheral portion of the pipe connected to the outlet of the evaporator, or By having a temperature-sensitive part that conducts heat from the vicinity of the outlet of the evaporator into the working pressure chamber, for example, the return passage becomes unnecessary for the valve body, so that the valve body of the thermal expansion valve can be miniaturized. Moreover, the temperature change of the refrigerant at the outlet of the evaporator can be detected more accurately.

It is a perspective view which shows the appearance of the 1st Example of the temperature type expansion valve which concerns on this invention. It is a left side view in the example shown in FIG. 1 shown together with a part of a pipe. FIG. 6 is a cross-sectional view taken along line III-III in FIG. 1, along with a portion of the pipe. It is sectional drawing which shows the structure of the 2nd Example of the temperature type expansion valve which concerns on this invention. It is sectional drawing which shows the structure of 3rd Example of the temperature type expansion valve which concerns on this invention. It is sectional drawing which shows the structure of the modification of the example shown in FIG. It is a figure which shows roughly the structure of the refrigeration cycle system to which each embodiment of the temperature type expansion valve which concerns on this invention is applied.

FIG. 1 shows the appearance of the first embodiment of the temperature type expansion valve according to the present invention.

The temperature type expansion valve including the valve body 10 and the valve body mechanism drive unit 12, which will be described later, is, for example, as shown in FIG. 7, the outlet of the condenser 4 and the evaporator 6 in the piping of the refrigerating cycle system mounted on the vehicle. It is located between the entrance and the entrance. The thermal expansion valve is connected to the aluminum alloy primary side pipe Du2 at the inlet port 10IN of the valve body 10, and is made of aluminum alloy at the outlet port 10OUT (see FIG. 3) of the valve body 10 from which the refrigerant flows out. It is connected to the secondary side pipe Du3 of. The primary side pipe Du2 connects the outlet of the condenser 4 and the valve body 10 of the temperature type expansion valve, and the secondary side pipe Du3 connects the inlet of the evaporator 6 and the outlet port 10OUT of the valve body 10 of the temperature type expansion valve. Is supposed to be connected to. A compressor 2 is connected between the outlet of the evaporator 6 and the inlet of the condenser 4 via pipes Du4 and Du1. One end of the pipe Du4 is connected to the suction port of the compressor 2 via the valve body mechanism drive unit 12 of the temperature type expansion valve. One end of the pipe Du1 connected to the discharge port of the compressor 2 is connected to the inlet of the condenser 4. The compressor 2 is driven and controlled by a control unit (not shown). This causes the refrigerant in the refrigeration cycle system to circulate, for example, along the arrow shown in FIG.

In FIG. 1, the temperature type expansion valve is a valve body 10 connected to the primary side pipe Du2 and the secondary side pipe Du3, and a valve body attached to the upper part of the valve body 10 to drive the valve body mechanism in the valve body 10. It is configured to include the mechanism drive unit 12 as a main element.

The valve body 10 is made of, for example, an aluminum alloy into a rectangular parallelepiped shape (aluminum block). As shown in FIGS. 2 and 3, both end faces 10A and 10B of the valve body 10 facing each other are connected to the inlet port 10IN connected to the primary side pipe Du2 and the secondary side pipe Du3, respectively. The exit port 10OUT is formed. Mounting female screw holes 10FMA and 10FMB are formed at positions adjacent to the inlet port 10IN and the outlet port 10OUT on the end faces 10A and 10B. The inlet port 10IN communicates with the valve body accommodating chamber 10R via the communication hole 10c. The valve body accommodating chamber 10R communicates with the coil spring accommodating portion 10D via a guide hole. The valve body accommodating chamber 10R, the guide hole described later, and the coil spring accommodating portion 10D are formed concentrically along the central axis of the valve body 10. In the valve body accommodating chamber 10R, a cylindrical valve body 30V having a truncated cone-shaped tip is movably arranged. The tip of the valve body 30V is in contact with a thin columnar tip of the connecting pin 28, which will be described later, via a valve port 10P that opens into the valve body accommodating chamber 10R. A spring pin 30 is press-fitted into the inner peripheral portion of the valve body 30V. The valve body 30V has a communication hole 30c for communicating the inner peripheral portion of the spring pin 30 and the valve body accommodating chamber 10R. By making the angle of the tip of the valve body 30V an acute angle, controllability is improved as compared with the case where the valve body is a ball valve, and the rate of change of the throttle passage per pressure change can be reduced. can. Further, when the valve body is a ball valve, the flow rate characteristic is determined to be a constant characteristic, but if the shape is a detailed shape, the flow rate characteristic can be made arbitrary by changing the taper angle in the middle.

The valve body accommodating chamber 10R communicates with the outlet port 10OUT via the valve port 10P and the relay flow path 10a. Further, the relay flow path 10a communicates with the female screw hole 10TS described later through the hole 10b and the gap between the inner peripheral portion of the guide hole and the outer peripheral portion of the connecting pin 28 described later.

The coil spring accommodating portion 10D has a coil spring 36 that urges the details of the valve body 30V closer to the valve port 10P, that is, a direction that closes the valve port 10P, and the urging force (restoring force) of the coil spring 36. ) Is arranged with the adjusting screw member 32. One end of the coil spring 36 is engaged with a step portion between the end portion of the valve body 30V and the spring pin 30, and the other end of the coil spring 36 is at the bottom of a recess formed in the inner peripheral portion of the adjusting screw member 32. It is in contact. The lower end of the adjusting screw member 32 has a male screw portion 32S screwed into the female screw portion 10FMC formed on the inner peripheral portion of the open end portion of the coil spring accommodating portion 10D. As a result, the male screw portion 32S advances or retracts with respect to the coil spring accommodating portion 10D against the urging force of the coil spring 36, so that the urging force of the coil spring 36 is adjusted. Further, an O-ring 34 that comes into contact with the inner peripheral surface of the coil spring accommodating portion 10D is loaded in the groove formed in the outer peripheral portion of the upper end portion of the adjusting screw member 32. As a result, the inside of the coil spring accommodating portion 10D is sealed to the outside.

A valve body mechanism drive unit 12 is attached to the upper female screw hole 10TS in the valve body 10. The valve body mechanism drive unit 12 has a circular upper lid 14 that abuts on a part of the outer peripheral portion VD of the pipe Du4 connected to the outlet of the above-mentioned evaporator 6 and receives the pipe Du4, and an internal space joined to the peripheral edge of the upper lid 14. A lower lid 16 formed in cooperation with the upper lid 14, a metal diaphragm 18 arranged in the internal space between the upper lid 14 and the lower lid 16, and a metal fitting on the surface of the diaphragm 18 facing the lower lid 16. It is configured to include a connecting pin 28, which is connected via 22;

The upper lid 14 has, for example, a joint portion 14B formed by press working with a thin metal material and joined to the peripheral edge of the lower lid 16, a circular seat portion 14T for receiving a partial outer peripheral portion VD of the pipe Du4, and a seat portion. It is composed of an annular connecting portion 14C that connects the 14T and the joining portion 14B. One end of a conduit 20 for guiding the working gas enclosed in the working pressure chamber 12A, which will be described later, is connected to a predetermined position in the connecting portion 14C. The other end of the conduit 20 is closed after the working gas is sealed in the working pressure chamber 12A.

The seat portion 14T has a recess 14R having a radius of curvature corresponding to the radius of curvature of the outer peripheral portion VD. As shown in FIG. 1, the recess 14R extends in the radial direction of the seat portion 14T. Further, the thickness T1 of the thin plate metal material forming the recess 14R is set thinner than the thickness T2 of the other portion of the seat portion 14T and the connecting portion 14C. The thicknesses T1 and T2 are set to, for example, 0.5 mm and 1.0 mm, respectively. As a result, the temperature-sensitive portion that transfers the heat from the pipe Du4 into the working pressure chamber 12A is formed by the seat portion 14T. Therefore, since the thermal resistance value (= wall thickness / thermal conductivity) of the recess 14R in contact with the outer peripheral portion VD is relatively small, the heat transfer efficiency of heat from the pipe Du4 to the working pressure chamber 12A is enhanced. At the same time, since the wall thickness of the portion other than the temperature sensitive portion is thicker than that of the temperature sensitive portion, the temperature sensitive portion is less likely to be affected by the ambient temperature (atmospheric temperature at which the temperature type expansion valve is installed).

As a result, the temperature detection accuracy of the temperature sensitive portion is improved. Further, since the temperature sensing portion is provided in the valve body mechanism drive unit 12, the return passage required for the expansion valve described in Patent Document 1 becomes unnecessary in the valve body 10, so that the valve of the temperature type expansion valve is not required. The size of the main body can be reduced. Further, since the temperature sensitive portion is provided on the upper lid, only the upper lid (the temperature sensitive portion) is provided between the outer peripheral portion VD and the working gas, so that the heat transfer efficiency does not decrease. An outer shell portion is formed by the upper lid 14 and the lower lid 16 described later in the valve body mechanism drive unit 12.

The peripheral edge of the diaphragm 18 that partitions the internal space between the upper lid 14 and the lower lid 16 is sandwiched and welded by the joint portion 14B of the upper lid 14 and the joint portion 16B of the lower lid 16. As a result, the working pressure chamber 12A is formed by being surrounded by the inner peripheral portion of the diaphragm 18 and the upper lid 14.

The connecting pin 28 connected via the metal portion 22 abutting on the central portion of the diaphragm 18 is arranged so that its central axis is substantially perpendicular to the pressure receiving surface of the diaphragm 18. The connecting pin 28 includes a fixed portion fixed to the money 22, a shaft portion extending from the fixed portion toward the relay flow path 10a, and a thin cylindrical tip portion formed at one end of the shaft portion. The shaft portion is slidably arranged in the guide hole of the guide portion formed in the central portion of the female screw hole 10TS. The diameter of the thin cylindrical tip is set smaller than the diameter of the shaft. A part of the thin cylindrical tip is inserted into the valve port 10P and abuts on the end face of the tip of the valve body 30V.

The lower lid 16 is formed of, for example, a joint portion 16B formed by press working with a thin metal material and joined to the peripheral edge of the upper lid 16, a cylindrical portion having a male screw portion screwed into the female screw hole 10TS, and a joint portion 16B. It is composed of an annular connecting portion that connects the and the cylindrical portion. The annular connecting portion is in contact with the O-ring 24 inserted in the upper groove of the valve body 10. As a result, the female screw hole 10TS is sealed to the outside.

An urging spring 26 is provided in the annular portion between the inner peripheral portion of the cylindrical portion of the lower lid 16 and the outer peripheral portion of the guide portion. The urging spring 26 is supposed to urge the connecting pin 28 to the diaphragm 18 via the buck. 22. As a result, the vibration of the connecting pin 28 can be suppressed, and abnormal noise due to contact between the parts (connecting pin 28, diaphragm 18, valve body 30) can be prevented.

FIG. 4 shows the configuration of the second embodiment of the temperature type expansion valve according to the present invention.

In the valve body mechanism drive unit 12 in the example shown in FIG. 3, the seat portion 14T of the circular upper lid 14 for receiving the pipe Du4 is a temperature-sensitive portion, whereas instead, it is shown in FIG. In the example, the flat portion 44P of the seat portion 44A of the upper lid 44 of the valve body mechanism drive unit 42 directly fixed to the outlet peripheral portion of the evaporator 6 is referred to as a temperature sensitive portion. In addition, FIG. 4 shows the same components as the components in the example shown in FIG. 3 with the same reference numerals, and the duplicate description thereof will be omitted.

The temperature expansion valve including the valve body 10 and the valve body mechanism drive unit 42 is, for example, as shown in FIG. 7, the outlet of the condenser 4 and the inlet of the evaporator 6 in the piping of the refrigerating cycle system mounted on the vehicle. It is placed between and.

The temperature type expansion valve is a valve body 10 connected to the primary side pipe Du2 and the secondary side pipe Du3, and a valve body mechanism drive unit 42 attached to the upper part of the valve body 10 and driving the valve body mechanism in the valve body 10. It is composed of and as the main elements.

The valve body mechanism drive unit 42 has a circular upper lid 44 having a flat portion 44P directly fixed to a flat portion around the outlet of the evaporator 6, and an internal space joined to the peripheral edge of the upper lid 44 with the upper lid 44. The lower lid 16 formed in cooperation with each other, the metal diaphragm 18 arranged in the internal space between the upper lid 44 and the lower lid 16, and the surface of the diaphragm 18 facing the lower lid 16 via the metal fitting 22. It is configured to include a connecting pin 28 to be connected.

The upper lid 44 has, for example, a joint portion 44B formed by press working with a thin metal material and joined to the peripheral edge of the lower lid 16, and a flat portion 44P fixed to a flat portion around the outlet of the evaporator 6. It is composed of a circular seat portion 44A and an annular connecting portion 44C that connects the seat portion 44A and the joint portion 44B. One end (not shown) of a conduit for guiding the working gas enclosed in the working pressure chamber 42A is connected to a predetermined position in the connecting portion 44C. The other end of the conduit is closed after the working gas is sealed in the working pressure chamber 42A. The seat portion 44A has a circular flat portion 44P. Further, the thickness T1 of the thin plate metal material forming the flat portion 44P is set thinner than the thickness T2 of the connecting portion 44C and the joining portion 44B. The thicknesses T1 and T2 are set to, for example, 0.5 mm and 1.0 mm, respectively. As a result, a temperature-sensitive portion that transfers heat from the vicinity of the outlet of the evaporator 6 into the working pressure chamber 42A is formed by the flat portion 44P of the seat portion 44A. Therefore, since the thermal resistance value (= wall thickness / thermal conductivity) of the flat portion 44P is relatively small, the heat transfer efficiency of heat from the outlet peripheral portion of the evaporator 6 to the working pressure chamber 42A is enhanced. At the same time, since the wall thickness of the portion other than the temperature sensitive portion is thicker than that of the temperature sensitive portion, the temperature sensitive portion is less likely to be affected by the ambient temperature (atmospheric temperature at which the temperature type expansion valve is installed).

The peripheral edge of the diaphragm 18 that partitions the internal space between the upper lid 44 and the lower lid 16 is sandwiched and welded by the joint portion 44B of the upper lid 44 and the joint portion 16B of the lower lid 16. As a result, the working pressure chamber 42A is formed by being surrounded by the diaphragm 18 and the inner peripheral portion of the upper lid 44. The lower lid 16 is formed of, for example, a joint portion 16B formed by press working with a thin metal material and joined to the peripheral edge of the upper lid 44, a cylindrical portion having a male screw portion screwed into the female screw hole 10TS, and a joint portion 16B. It is composed of an annular connecting portion that connects the and the cylindrical portion. An urging spring 26 is provided in the annular portion between the inner peripheral portion of the cylindrical portion of the lower lid 16 and the outer peripheral portion of the guide portion. The urging spring 26 is supposed to urge the connecting pin 28 to the diaphragm 18 via the buck. 22. As a result, vibration of the connecting pin 28 can be suppressed, and abnormal noise due to contact between parts (connecting pin 28, diaphragm 18, valve body 30) can be prevented.

FIG. 5 shows the configuration of the third embodiment of the temperature type expansion valve according to the present invention.

In the valve body mechanism drive unit 12 in the example shown in FIG. 3, the seat portion 14T of the circular upper lid 14 integrally molded of the same material for receiving the pipe Du4 is used as the temperature sensitive portion. Instead, in the example shown in FIG. 5, in the upper lid 54, the material of the seat portion 54A of the upper lid 54 and the material of the connecting portion 54C and the joint portion 54B of the upper lid 54 are different from each other. In addition, FIG. 5 shows the same components as the components in the example shown in FIG. 3 with the same reference numerals, and the duplicate description thereof will be omitted.

The temperature expansion valve including the valve body 10 and the valve body mechanism drive unit 52 is, for example, as shown in FIG. 7, the outlet of the condenser 4 and the inlet of the evaporator 6 in the piping of the refrigerating cycle system mounted on the vehicle. It is placed between and.

The temperature type expansion valve is a valve body 10 connected to the primary side pipe Du2 and the secondary side pipe Du3, and a valve body mechanism drive unit 52 attached to the upper part of the valve body 10 and driving the valve body mechanism in the valve body 10. It is composed of and as the main elements.

The valve body mechanism drive unit 52 has a circular upper lid 54 that abuts on a part of the outer peripheral portion VD of the pipe Du4 connected to the outlet of the above-mentioned evaporator 6 and receives the pipe Du4, and an internal space joined to the peripheral edge of the upper lid 54. A lower lid 16 formed in cooperation with the upper lid 54, a metal diaphragm 18 arranged in the internal space between the upper lid 54 and the lower lid 16, and a metal fitting on the surface of the diaphragm 18 facing the lower lid 16. It is configured to include a connecting pin 28, which is connected via 22;

The upper lid 54 is composed of a joint portion 54B joined to the peripheral edge of the lower lid 16, a circular seat portion 54A for receiving the pipe Du4, and an annular connecting portion 54C connecting the seat portion 54A and the joint portion 54B. There is. One end of a conduit 20 for guiding the working gas enclosed in the working pressure chamber 52A, which will be described later, is connected to a predetermined position in the connecting portion 54C. The other end of the conduit 20 is closed after the working gas is sealed in the working pressure chamber 52A. The seat portion 54A is made of, for example, a thin plate material of a copper alloy in a circular shape, and has a recess 54R having a radius of curvature corresponding to the radius of curvature of the outer peripheral portion VD. The recess 54R extends in the radial direction of the seat portion 54A. The connecting portion 54C and the joining portion 54B are made of, for example, a thin plate material of stainless steel. As a result, the thermal conductivity of the recess 54R becomes larger than the thermal conductivity of the connecting portion 54C and the joining portion 54B. The entire peripheral edge of the seat portion 54A is welded to the entire peripheral edge of the connecting portion 54C. As a result, a temperature-sensitive portion that transfers heat from the pipe Du4 into the working pressure chamber 52A is formed by the seat portion 54A. Therefore, the thermal conductivity of the recess 54R that abuts on the outer peripheral portion VD is larger than the thermal conductivity of the connecting portion 54C and the joining portion 54B, so that the heat transfer efficiency from the pipe Du4 to the working pressure chamber 52A is high. Be enhanced. At the same time, since the thermal conductivity of the portion other than the temperature sensitive portion is smaller than that of the temperature sensitive portion, the temperature sensitive portion is less likely to be affected by the ambient temperature (atmospheric temperature in which the temperature type expansion valve is installed).

The peripheral edge of the diaphragm 18 that partitions the internal space between the upper lid 54 and the lower lid 16 is sandwiched and welded by the joint portion 54B of the upper lid 54 and the joint portion 16B of the lower lid 16. As a result, the working pressure chamber 52A is formed by being surrounded by the diaphragm 18 and the inner peripheral portion of the upper lid 54.

An urging spring 26 is provided in the annular portion between the inner peripheral portion of the cylindrical portion of the lower lid 16 and the outer peripheral portion of the guide portion. The urging spring 26 is supposed to urge the connecting pin 28 to the diaphragm 18 via the buck. 22. As a result, vibration of the connecting pin 28 can be suppressed, and abnormal noise due to contact between parts (connecting pin 28, diaphragm 18, valve body 30) can be prevented.

In the example shown in FIG. 5 above, the entire peripheral edge of the seat portion 54A is welded to the entire peripheral edge of the connecting portion 54C, but the present invention is not limited to such an example, and is shown in FIG. As such, the circular seat portion 64A for receiving the pipe Du4 in the upper lid 64 of the valve body mechanism drive unit 62 may be joined to the peripheral edge of the circular open end in the inner peripheral portion of the connecting portion 64C by brazing. In addition, FIG. 6 shows the same components as the components in the example shown in FIG. 3 with the same reference numerals, and the duplicate description thereof will be omitted.

In FIG. 6, the temperature type expansion valve is a valve body 10 connected to the primary side pipe Du2 and the secondary side pipe Du3, and a valve body attached to the upper part of the valve body 10 to drive the valve body mechanism in the valve body 10. It is configured to include the mechanism drive unit 62 as a main element.

The valve body mechanism drive unit 62 has a circular upper lid 64 that abuts on a part of the outer peripheral portion VD of the pipe Du4 connected to the outlet of the above-mentioned evaporator 6 to receive the pipe Du4, and an internal space joined to the peripheral edge of the upper lid 64. A lower lid 16 formed in cooperation with the upper lid 64, a metal diaphragm 18 arranged in the internal space between the upper lid 64 and the lower lid 16, and a metal fitting on the surface of the diaphragm 18 facing the lower lid 16. It is configured to include a connecting pin 28, which is connected via 22;

The upper lid 64 is composed of a joint portion 64B joined to the peripheral edge of the lower lid 16, a circular seat portion 64A for receiving the pipe Du4, and an annular connecting portion 64C connecting the seat portion 64A and the joint portion 64B. There is. One end of a conduit 20 for guiding the working gas enclosed in the working pressure chamber 62A, which will be described later, is connected to a predetermined position in the connecting portion 64C. The other end of the conduit 20 is closed after the working gas is sealed in the working pressure chamber 62A. The seat portion 64A is made of, for example, a thin plate material of a copper alloy in a circular shape, and has a recess 64R having a radius of curvature corresponding to the radius of curvature of the outer peripheral portion VD. The recess 64R extends in the radial direction of the seat portion 64A. The connecting portion 64C and the joining portion 64B are made of, for example, a thin plate material of stainless steel. As a result, the thermal conductivity of the recess 64R becomes larger than the thermal conductivity of the connecting portion 64C and the joining portion 64B. As a result, the temperature-sensitive portion that transfers the heat from the pipe Du4 into the working pressure chamber 62A is formed by the seat portion 64A. Therefore, the thermal conductivity of the recess 64R that abuts on the outer peripheral portion VD is larger than the thermal conductivity of the connecting portion 64C and the joining portion 64B, so that the heat transfer efficiency from the pipe Du4 to the working pressure chamber 62A is high. Be enhanced. At the same time, since the thermal conductivity of the portion other than the temperature sensitive portion is smaller than that of the temperature sensitive portion, the temperature sensitive portion is less likely to be affected by the ambient temperature (atmospheric temperature in which the temperature type expansion valve is installed).

6 Evaporator 10 Valve body 10P Valve port 10IN Inlet port 10OUT Outlet port 12, 42, 52, 62 Valve body mechanism drive unit 12A, 42A, 52A, 62A Operating pressure chamber 14, 44, 54, 64 Top lid 14R, 54R, 64R Recess 16 Lower lid 18 Diaphragm Du4 Piping

Claims (4)

A valve body that is arranged in a pipe that supplies the refrigerant to the evaporator and has a flow path that guides the refrigerant.
A valve body mechanism that is arranged in the valve body so as to be close to or separated from the valve port of the valve seat formed in the flow path and controls the opening area of the valve port.
The valve body mechanism is driven via a connecting pin which is arranged at an end of the valve body separated from the flow path and is connected to the diaphragm according to the pressure in the working pressure chamber formed by the diaphragm and the outer member. With a valve body drive unit,
The outer member of the valve body mechanism drive unit is a temperature-sensitive portion formed by a thin metal plate portion, and is an outer peripheral portion of a pipe connected to the outlet of the evaporator or a peripheral portion of the outlet of the evaporator. It has a temperature sensitive part that conducts heat from the operating pressure chamber into the working pressure chamber.
The temperature-sensitive portion is formed between the outer peripheral portion of the pipe and the working pressure chamber, and is formed in a recess for receiving the outer peripheral portion of the pipe by a thin peripheral edge, or a flat portion around the outlet of the evaporator. Has a flat part that is directly fixed ,
The thermal resistance value of the temperature-sensitive portion is smaller than the thermal resistance value of the other portion of the outer member.
A temperature-type expansion valve characterized in that the thickness of the temperature-sensitive portion is smaller than the thickness of other portions of the outer member . The temperature-type expansion valve according to claim 1 , wherein the thermal conductivity of the temperature-sensitive portion is higher than the thermal conductivity of other portions of the outer member. The temperature type expansion valve according to claim 1, wherein the valve body mechanism drive unit further includes an urging spring that urges the connecting pin to the diaphragm. Equipped with an evaporator, a compressor, and a condenser,
A refrigeration cycle according to any one of claims 1 to 3 , wherein the temperature expansion valve is provided in a pipe arranged between an outlet of the condenser and an inlet of the evaporator. system.

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