EP4067777A1 - Power element and expansion valve used therein - Google Patents
Power element and expansion valve used therein Download PDFInfo
- Publication number
- EP4067777A1 EP4067777A1 EP22163460.3A EP22163460A EP4067777A1 EP 4067777 A1 EP4067777 A1 EP 4067777A1 EP 22163460 A EP22163460 A EP 22163460A EP 4067777 A1 EP4067777 A1 EP 4067777A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- cylindrical portion
- main body
- valve
- power element
- valve main
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B41/00—Fluid-circulation arrangements
- F25B41/30—Expansion means; Dispositions thereof
- F25B41/31—Expansion valves
- F25B41/33—Expansion valves with the valve member being actuated by the fluid pressure, e.g. by the pressure of the refrigerant
- F25B41/335—Expansion valves with the valve member being actuated by the fluid pressure, e.g. by the pressure of the refrigerant via diaphragms
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B2341/00—Details of ejectors not being used as compression device; Details of flow restrictors or expansion valves
- F25B2341/06—Details of flow restrictors or expansion valves
Definitions
- the present invention relates to a power element and an expansion valve used therein.
- temperature-sensitive expansion valves are used that adjust the amount of refrigerant passing through according to the temperature.
- Patent Document 1 Japanese Unexamined Patent Application Publication No. 2017-198373
- Patent Document 1 has an inlet port into which a high-pressure refrigerant is introduced and a valve chamber communicating with the inlet port, and the top of a valve main body is equipped with a drive mechanism for a valve member, referred to as a power element.
- a spherical valve element arranged in the valve chamber faces a valve seat that opens in the valve chamber, and is operated by an operation rod driven by the power element to control the opening of the throttle passage with the valve seat.
- the power element is composed of an upper lid member that forms a pressure working chamber, a thin plate diaphragm that elastically deforms under pressure, and a receiving member that is fixed to the valve main body.
- a working gas is enclosed in the pressure working chamber formed by the upper lid member and the diaphragm.
- a stopper member is arranged in the lower space between the diaphragm and the receiving member.
- an object of the present invention is to provide a power element and an expansion valve used therein that are capable of maintaining sealability while reducing the size of the expansion valve and suppressing deterioration of controllability.
- the expansion valve includes a valve main body; a power element mounted on the valve main body; and a seal provided between the valve main body and the power element.
- the power element includes: an upper lid member; a receiving member; and a diaphragm interposed between the upper lid member and the receiving member, the receiving member is formed by press working, and includes a cylindrical portion and an annular flange portion that is adjacent to the cylindrical portion and extends in an outer circumferential direction of the cylindrical portion, the cylindrical portion of the receiving member is fixed to the valve main body, and the seal is provided in a seal space formed between the cylindrical portion, the annular flange portion, and the valve main body, and a cutting process is performed on a region of the cylindrical portion adjacent to the annular flange portion, and the region forms a part of the seal space.
- a power element and an expansion valve used therein that are capable of maintaining sealability while reducing the size of the expansion valve and suppressing deterioration of controllability.
- the direction extending from the valve element 3 toward the operation rod 5 is defined as the "upward direction,” and the direction extending from the operation rod 5 toward the valve element 3 is defined as the “downward direction.” Accordingly, in the present specification, the direction extending from the valve element 3 toward the operation rod 5 is referred to as the "upward direction” regardless of the orientation of the expansion valve 1.
- FIG. 1 is a schematic cross-sectional view schematically illustrating an example in which the expansion valve 1 according to the present embodiments is applied to a refrigerant circulation system 100.
- FIG. 2 is an enlarged cross-sectional view illustrating the vicinity of the power element in the expansion valve of FIG 1 .
- FIG. 3 is a cross-sectional view illustrating the power element of the present embodiment alone.
- the expansion valve 1 is fluidly connected to a compressor 101, a condenser 102, and an evaporator 104.
- L is set as the axis of the expansion valve 1.
- the expansion valve 1 includes a valve main body 2 having a valve chamber VS, a valve element 3, a biasing device 4, an operation rod 5, and a power element 8.
- the valve main body 2 includes a first flow path 21, a second flow path 22, an intermediate chamber 221, and a return flow path 23 in addition to the valve chamber VS.
- the first flow path 21 is a supply-side flow path, and a refrigerant (also referred to as a fluid) is supplied to the valve chamber VS via the supply-side flow path.
- the second flow path 22 is a discharge-side flow path (also referred to as an outlet-side flow path), and the fluid in the valve chamber VS is discharged to the outside of the expansion valve through a valve through-hole 27, the intermediate chamber 221 and the discharge-side flow path.
- the first flow path 21 and the valve chamber VS communicate with each other by a connection path 21a having a smaller diameter than the first flow path 21.
- the valve chamber VS and the intermediate chamber 221 communicate with each other via the valve seat 20 and the valve through-hole 27.
- the operation rod insertion hole 28 formed above the intermediate chamber 221 has a function for guiding the operation rod 5, and the annular recess 29 formed above the operation rod insertion hole 28 has a function of accommodating a ring spring 6.
- the ring spring 6 applies a predetermined biasing force by coming into contact with a plurality of springs on the outer circumference of the operation rod 5.
- the valve element 3 is arranged in the valve chamber VS.
- the valve element 3 When the valve element 3 is seated on the valve seat 20 of the valve main body 2, the flow of the refrigerant through the valve through-hole 27 is restricted. This state is referred to as a non-communicating state. However, even in the case that the valve element 3 is seated on the valve seat 20, a limited amount of refrigerant may flow. On the other hand, when the valve element 3 is separated from the valve seat 20, the flow of the refrigerant passing through the valve through-hole 27 increases. This state is referred to as a communication state.
- the operation rod 5 is inserted into the valve through-hole 27 with a predetermined gap.
- the lower end of the operation rod 5 is in contact with the upper surface of the valve element 3.
- the upper end of the operation rod 5 is fitted into a fitting hole 84c of the stopper member 84, which will be described later.
- the operation rod 5 can press the valve element 3 in a valve opening direction against the biasing force of the biasing device 4. When the operation rod 5 moves downward, the valve element 3 is separated from the valve seat 20 and the expansion valve 1 is opened.
- the biasing device 4 includes a coil spring 41 in which a wire member having a circular cross section is spirally wound, a valve element support 42, and a spring receiving member 43.
- valve element support 42 is attached to the upper end of the coil spring 41, a spherical valve element 3 is welded to the upper surface thereof, and both are integrated together.
- the spring receiving member 43 that supports the lower end of the coil spring 41 can be screwed against the valve main body 2, and has a function of sealing the valve chamber VS and a function of adjusting the biasing force of the coil spring 41.
- the power element 8 includes a plug 81, an upper lid member 82, a diaphragm 83, a receiving member 86, and a stopper member 84.
- An opening 82a is formed at the top of the substantially conical upper lid member 82, and can be sealed by the plug 81.
- the diaphragm 83 is made of a thin metal (SUS, for example) plate material in which a plurality of concentric, uneven shapes are formed, and has an outer diameter substantially the same as the outer diameter of the upper lid member 82 and the receiving member 86.
- SUS thin metal
- the receiving member 86 includes a first annular flange portion 86a having an outer diameter substantially the same as the outer diameter of the upper lid member 82, a first cylindrical portion 86b which is connected to the inner circumference of the first annular flange portion 86a, a second annular flange portion 86c which is connected to the lower end of the first cylindrical portion 86b and extends inward in the radial direction, and a second cylindrical portion 86d which is connected to the inner circumference of the second annular flange portion 86c.
- a male screw portion 86e is formed on the outer circumference of the second cylindrical portion 86d on the lower end side.
- a method of manufacturing the receiving member 86 will be described.
- a transition portion TF having an arcuate cross section (a taper shape that increases in diameter toward the top) that may reduce the sealing properties of the seal is generated at a boundary portion between the second annular flange portion 86c and the second cylindrical portion 86d that extend in directions orthogonal to each other.
- the filling rate of the ring-shaped seal (also referred to as packing) SL housed in the seal space SP may exceed 100%, and there is a risk that the seal SL may protrude. If a seal SL having a small cross section is adopted to prevent this, the sealing properties of the seal SL may be lowered, and the durability of the seal SL may also be lowered.
- a cutting process is performed on the second cylindrical portion 86d adjacent to the second annular flange portion 86c to remove the transition portion TF. More specifically, the receiving member 86 is gripped by the chuck, and the cutting tool is brought closer along the second annular flange portion 86c from the radial direction while rotating around the axis L. In the seal recess 2c in the radial direction, a cutting process is performed on the transition portion TF to form a cylindrical surface parallel to the axis L, and the flat lower surface of the second annular flange portion 86c is expanded.
- the male screw portion 86e is formed on the outer circumference of the second cylindrical portion 86d by a cutting process or the like without separating from the chuck. It should be noted that, even after cut processing, the fine R-shape of the rake face of the cutting tool is transferred to the boundary portion between the second annular flange portion 86c and the second cylindrical portion 86d, but since the R-shape is much smaller than the transition portion TF formed by press working, the volume of the seal space SP is hardly limited.
- the space between the second annular flange portion 86c and the male screw portion 86e is a cut-processed cylindrical surface and forms a part of the seal space SP, such that a large seal space SP formed between the receiving member 86 and the seal recess 2c of the valve main body 2 can be secured. Accordingly, a seal SL having a relatively large cross section (here, a rectangular cross section) can be adopted, and the sealing performance and durability of the seal can be improved.
- the stopper member 84 includes a disc portion 84a facing the diaphragm 83, a cylindrical main body 84b connected below the disc portion 84a, and a bag hole-shaped fitting hole 84c formed in the center of the lower surface of the main body 84b.
- the outer circumference of the lower surface of the disc portion 84a is supported by the upper surface of the second annular flange portion 86c.
- the procedure for assembling the power element 8 will be described. While placing the stopper member 84 between the diaphragm 83 and the receiving member 86, the outer circumferential portions of the upper lid member 82, the diaphragm 83, and the receiving member 86 are overlapped with each other, and the outer circumferential portions are circumferentially welded by, for example, TIG welding, laser welding, plasma welding, or the like to integrate them.
- the working gas is sealed in the space (referred to as the pressure working chamber PO) surrounded by the upper lid member 82 and the diaphragm 83 from the opening 82a formed in the upper lid member 82, and then the opening 82a is sealed with the plug 81. Further, the plug 81 is fixed to the upper lid member 82 by projection welding or the like.
- the diaphragm 83 receives pressure in a form of projecting toward the receiving member 86 due to the working gas sealed in the pressure working chamber PO, it is supported in contact with the upper surface of the stopper member 84 arranged in the lower space LS surrounded by the diaphragm 83 and the receiving member 86.
- the male screw portion 86e provided on the outer circumference of the lower end of the second cylindrical portion 86d of the receiving member 86 is screwed into the female screw portion 2b formed on the inner circumference of the recess 2a communicating with the return flow path 23 of the valve main body 2.
- the male screw portion 86e is screwed with respect to the female screw portion 2b, the lower end of the receiving member 86 comes into contact with the upper end surface of the valve main body 2.
- the power element 8 can be fixed to the valve main body 2.
- the seal SL interposed in the seal space SP between the power element 8 and the valve main body 2 prevents the refrigerant from leaking from the recess 2a when the power element 8 is attached to the valve main body 2.
- the lower space LS of the power element 8 communicates with the return flow path 23; that is, the same internal pressure is obtained.
- the refrigerant pressurized by the compressor 101 is liquefied by the condenser 102 and sent to the expansion valve 1. Further, the refrigerant adiabatically expanded by the expansion valve 1 is sent to the evaporator 104, and the evaporator 104 exchanges heat with the air flowing around the evaporator. The refrigerant returning from the evaporator 104 is returned to the compressor 101 side through the expansion valve 1 (more specifically, the return flow path 23). At this time, by passing through the evaporator 104, the fluid pressure in the second flow path 22 becomes larger than the fluid pressure in the return flow path 23.
- a high-pressure refrigerant is supplied to the expansion valve 1 from the condenser 102. More specifically, the high-pressure refrigerant from the condenser 102 is supplied to the valve chamber VS via the first flow path 21.
- valve element 3 When the valve element 3 is seated on the valve seat 20 (when in the non-communicating state), the flow rate of the refrigerant sent from the valve chamber VS to the evaporator 104 through the valve through-hole 27, the intermediate chamber 221 and the second flow path 22 is limited. On the other hand, when the valve element 3 is separated from the valve seat 20 (when in the communicating state), the flow rate of the refrigerant sent from the valve chamber VS to the evaporator 104 through the valve through-hole 27, the intermediate chamber 221 and the second flow path 22 increases. Switching between the closed state and the open state of the expansion valve 1 is performed by the operation rod 5 connected to the power element 8 via the stopper member 84.
- a pressure working chamber PO and a lower space LS partitioned by a diaphragm 83 are provided inside the power element 8. Accordingly, when the working gas in the pressure working chamber PO is liquefied, the diaphragm 83 and the stopper member 84 rise, such that the operation rod 5 moves upward according to the biasing force of the coil spring 41. On the other hand, when the liquefied working gas is vaporized, the diaphragm 83 and the stopper member 84 are pressed downward, such that the operation rod 5 moves downward. In this way, the expansion valve 1 is switched between an open state and a closed state.
- the lower space LS of the power element 8 communicates with the return flow path 23. Accordingly, the volume of the working gas in the pressure working chamber PO changes according to the temperature and pressure of the refrigerant flowing through the return flow path 23, and the operation rod 5 is driven.
- the amount of the refrigerant supplied from the expansion valve 1 toward the evaporator 104 is automatically adjusted according to the temperature and pressure of the refrigerant returning from the evaporator 104 to the expansion valve 1.
- the power element 8 since the power element 8 is not miniaturized, it is not necessary to change the inner diameter of the receiving member 86, and since the flow of the refrigerant flowing from the return flow path 23 into the lower space LS does not change, deterioration of the controllability of the valve element 3 can be suppressed. It should be noted that the deterioration of the controllability means that an actual value greatly exceeds a target value or that an actual value fluctuates up or down with respect to a target value.
- FIG. 4 is an enlarged cross-sectional view illustrating the vicinity of the power element of the expansion valve according to the second embodiment.
- FIG. 5 is a cross-sectional view illustrating the power element 8A of the present embodiment alone.
- the present embodiment differs from the above-described embodiment only in the shape of the receiving member 86A of the power element 8A. Since the other configurations are the same as those in the above-described embodiment, the same reference numerals are given and redundant description will be omitted.
- a method of manufacturing the receiving member 86A will be described. Similar to the embodiment described above, a metal plate material is press-molded to form a first annular flange portion 86Aa, a first cylindrical portion 86Ab, a second annular flange portion 86Ac, and a second cylindrical portion 86Ad.
- a reduced diameter portion 86Af is formed by performing a cutting process on the boundary portion between the second annular flange portion 86Ac and the second cylindrical portion 86Ad that extend in directions orthogonal to each other.
- the outer diameter of the reduced diameter portion 86Af is smaller than the thread outer diameter of the male screw portion 86Ae.
- a larger seal space SP formed between the receiving member 86A and the seal recess 2c of the valve main body 2 can be secured. Accordingly, a seal SL having a larger cross section can be adopted, and the sealability and durability of the seal can be improved.
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- Thermal Sciences (AREA)
- General Engineering & Computer Science (AREA)
- Temperature-Responsive Valves (AREA)
- Fluid-Driven Valves (AREA)
Abstract
Description
- The present application claims priority to
Japanese Patent Application No. 2021-055966, filed March 29, 2021 - The present invention relates to a power element and an expansion valve used therein.
- Conventionally, in the refrigeration cycles used in air conditioners or the like mounted in automobiles, temperature-sensitive expansion valves are used that adjust the amount of refrigerant passing through according to the temperature.
- For example, the expansion valve illustrated in
Japanese Unexamined Patent Application Publication No. 2017-198373 - The power element is composed of an upper lid member that forms a pressure working chamber, a thin plate diaphragm that elastically deforms under pressure, and a receiving member that is fixed to the valve main body. In addition, a working gas is enclosed in the pressure working chamber formed by the upper lid member and the diaphragm. Further, a stopper member is arranged in the lower space between the diaphragm and the receiving member.
- In such a power element, heat is transferred between the refrigerant flowing from the valve main body into the lower space and the working gas of the pressure working chamber, and as a result, when the internal pressure of the pressure working chamber is relatively increased, the diaphragm deforms so as to expand the pressure working chamber, thereby pressing the stopper member to press the operation rod and separate the valve element from the valve seat. On the other hand, when the internal pressure of the pressure working chamber relatively decreases, the deformation of the diaphragm reverses, and the pressing force of the operation rod disappears, so that the valve element sits on the valve seat.
- Incidentally, it is desirable to reduce the weight of vehicle bodies for the purpose of suppressing the fuel consumption of automobiles, and accordingly, there is a demand for miniaturization and weight reduction with respect to in-vehicle components like expansion valves. However, if the power element is miniaturized in accordance with the miniaturization of the valve main body, the flow of the refrigerant flowing from the valve main body into the lower space of the power element may change, resulting in deterioration of controllability.
- Accordingly, it has been proposed to miniaturize the valve main body without miniaturizing the power element in order to miniaturize the expansion valve while suppressing the deterioration of controllability. However, according to the results of consideration by the present inventors, in the case that the valve main body is miniaturized without miniaturizing the power element, it has been found that the sealing properties between the power element and the valve main body deteriorate.
- Accordingly, an object of the present invention is to provide a power element and an expansion valve used therein that are capable of maintaining sealability while reducing the size of the expansion valve and suppressing deterioration of controllability.
- In order to achieve the above object, the expansion valve according to the present invention includes a valve main body; a power element mounted on the valve main body; and a seal provided between the valve main body and the power element. The power element includes: an upper lid member; a receiving member; and a diaphragm interposed between the upper lid member and the receiving member, the receiving member is formed by press working, and includes a cylindrical portion and an annular flange portion that is adjacent to the cylindrical portion and extends in an outer circumferential direction of the cylindrical portion, the cylindrical portion of the receiving member is fixed to the valve main body, and the seal is provided in a seal space formed between the cylindrical portion, the annular flange portion, and the valve main body, and a cutting process is performed on a region of the cylindrical portion adjacent to the annular flange portion, and the region forms a part of the seal space.
- According to the present invention, it is possible to provide a power element and an expansion valve used therein that are capable of maintaining sealability while reducing the size of the expansion valve and suppressing deterioration of controllability.
-
- [
Figure 1] FIG. 1 is a schematic cross-sectional view schematically illustrating an example in which the expansion valve according to the present embodiments is applied to a refrigerant circulation system. - [
Figure 2] FIG. 2 is an enlarged cross-sectional view illustrating the vicinity of the power element in the expansion valve ofFIG 1 . - [
Figure 3] FIG. 3 is a cross-sectional view illustrating the power element of the present embodiment alone. - [
Figure 4] FIG. 4 is an enlarged cross-sectional view illustrating the vicinity of the power element of the expansion valve according to the second embodiment. - [
Figure 5] FIG. 5 is a cross-sectional view illustrating the power element of the present embodiment alone. - Hereinafter, the embodiments according to the present invention will be described with reference to the figures.
- In the present specification, the direction extending from the
valve element 3 toward theoperation rod 5 is defined as the "upward direction," and the direction extending from theoperation rod 5 toward thevalve element 3 is defined as the "downward direction." Accordingly, in the present specification, the direction extending from thevalve element 3 toward theoperation rod 5 is referred to as the "upward direction" regardless of the orientation of theexpansion valve 1. - An overview of the
expansion valve 1 according to the present embodiments will be described with reference toFIG. 1 andFIG. 2 .FIG. 1 is a schematic cross-sectional view schematically illustrating an example in which theexpansion valve 1 according to the present embodiments is applied to arefrigerant circulation system 100.FIG. 2 is an enlarged cross-sectional view illustrating the vicinity of the power element in the expansion valve ofFIG 1 .FIG. 3 is a cross-sectional view illustrating the power element of the present embodiment alone. - In the present embodiment, the
expansion valve 1 is fluidly connected to acompressor 101, acondenser 102, and anevaporator 104. L is set as the axis of theexpansion valve 1. - In
FIG. 1 , theexpansion valve 1 includes a valvemain body 2 having a valve chamber VS, avalve element 3, abiasing device 4, anoperation rod 5, and apower element 8. - The valve
main body 2 includes afirst flow path 21, asecond flow path 22, anintermediate chamber 221, and areturn flow path 23 in addition to the valve chamber VS. Thefirst flow path 21 is a supply-side flow path, and a refrigerant (also referred to as a fluid) is supplied to the valve chamber VS via the supply-side flow path. Thesecond flow path 22 is a discharge-side flow path (also referred to as an outlet-side flow path), and the fluid in the valve chamber VS is discharged to the outside of the expansion valve through a valve through-hole 27, theintermediate chamber 221 and the discharge-side flow path. - The
first flow path 21 and the valve chamber VS communicate with each other by aconnection path 21a having a smaller diameter than thefirst flow path 21. The valve chamber VS and theintermediate chamber 221 communicate with each other via thevalve seat 20 and the valve through-hole 27. - The operation
rod insertion hole 28 formed above theintermediate chamber 221 has a function for guiding theoperation rod 5, and theannular recess 29 formed above the operationrod insertion hole 28 has a function of accommodating aring spring 6. Thering spring 6 applies a predetermined biasing force by coming into contact with a plurality of springs on the outer circumference of theoperation rod 5. - The
valve element 3 is arranged in the valve chamber VS. When thevalve element 3 is seated on thevalve seat 20 of the valvemain body 2, the flow of the refrigerant through the valve through-hole 27 is restricted. This state is referred to as a non-communicating state. However, even in the case that thevalve element 3 is seated on thevalve seat 20, a limited amount of refrigerant may flow. On the other hand, when thevalve element 3 is separated from thevalve seat 20, the flow of the refrigerant passing through the valve through-hole 27 increases. This state is referred to as a communication state. - The
operation rod 5 is inserted into the valve through-hole 27 with a predetermined gap. The lower end of theoperation rod 5 is in contact with the upper surface of thevalve element 3. The upper end of theoperation rod 5 is fitted into afitting hole 84c of thestopper member 84, which will be described later. - The
operation rod 5 can press thevalve element 3 in a valve opening direction against the biasing force of thebiasing device 4. When theoperation rod 5 moves downward, thevalve element 3 is separated from thevalve seat 20 and theexpansion valve 1 is opened. - The
biasing device 4 includes acoil spring 41 in which a wire member having a circular cross section is spirally wound, a valve element support 42, and aspring receiving member 43. - The
valve element support 42 is attached to the upper end of thecoil spring 41, aspherical valve element 3 is welded to the upper surface thereof, and both are integrated together. - The
spring receiving member 43 that supports the lower end of thecoil spring 41 can be screwed against the valvemain body 2, and has a function of sealing the valve chamber VS and a function of adjusting the biasing force of thecoil spring 41. - Next, the
power element 8 will be described. As illustrated inFIG. 2 , thepower element 8 includes aplug 81, anupper lid member 82, adiaphragm 83, a receivingmember 86, and astopper member 84. - An opening 82a is formed at the top of the substantially conical
upper lid member 82, and can be sealed by theplug 81. - The
diaphragm 83 is made of a thin metal (SUS, for example) plate material in which a plurality of concentric, uneven shapes are formed, and has an outer diameter substantially the same as the outer diameter of theupper lid member 82 and the receivingmember 86. - The receiving
member 86 includes a firstannular flange portion 86a having an outer diameter substantially the same as the outer diameter of theupper lid member 82, a firstcylindrical portion 86b which is connected to the inner circumference of the firstannular flange portion 86a, a secondannular flange portion 86c which is connected to the lower end of the firstcylindrical portion 86b and extends inward in the radial direction, and a secondcylindrical portion 86d which is connected to the inner circumference of the secondannular flange portion 86c. Amale screw portion 86e is formed on the outer circumference of the secondcylindrical portion 86d on the lower end side. - Here, a method of manufacturing the receiving
member 86 will be described. First a metal plate material is press-molded to form the firstannular flange portion 86a, the firstcylindrical portion 86b, the secondannular flange portion 86c and the secondcylindrical portion 86d. After the press-molding, as illustrated by the dotted line inFIG. 3 , a transition portion TF having an arcuate cross section (a taper shape that increases in diameter toward the top) that may reduce the sealing properties of the seal is generated at a boundary portion between the secondannular flange portion 86c and the secondcylindrical portion 86d that extend in directions orthogonal to each other. - More specifically, first, in order to suppress the deterioration of controllability of the
valve element 3, it is necessary to secure a large inner diameter of the secondcylindrical portion 86d, and so a method that does not miniaturize thepower element 8 is used. In such a case, if the valvemain body 2 is miniaturized in order to miniaturize theentire expansion valve 1, the area of the upper end surface of the valvemain body 2 is reduced. When thepower element 8 in which the transition portion TF is generated is attached to the valvemain body 2, the volume of the seal space SP (FIG. 2 ) formed between the receivingmember 86 and theseal recess 2c of the valve main body 2 (between the secondcylindrical portion 86d, the secondannular flange portion 86c, and the valve main body 2) is limited by the transition portion TF. Accordingly, the filling rate of the ring-shaped seal (also referred to as packing) SL housed in the seal space SP may exceed 100%, and there is a risk that the seal SL may protrude. If a seal SL having a small cross section is adopted to prevent this, the sealing properties of the seal SL may be lowered, and the durability of the seal SL may also be lowered. - Accordingly, in the present embodiment, after press molding, a cutting process is performed on the second
cylindrical portion 86d adjacent to the secondannular flange portion 86c to remove the transition portion TF. More specifically, the receivingmember 86 is gripped by the chuck, and the cutting tool is brought closer along the secondannular flange portion 86c from the radial direction while rotating around the axis L. In theseal recess 2c in the radial direction, a cutting process is performed on the transition portion TF to form a cylindrical surface parallel to the axis L, and the flat lower surface of the secondannular flange portion 86c is expanded. In addition, themale screw portion 86e is formed on the outer circumference of the secondcylindrical portion 86d by a cutting process or the like without separating from the chuck. It should be noted that, even after cut processing, the fine R-shape of the rake face of the cutting tool is transferred to the boundary portion between the secondannular flange portion 86c and the secondcylindrical portion 86d, but since the R-shape is much smaller than the transition portion TF formed by press working, the volume of the seal space SP is hardly limited. - According to the present embodiment, in the second
cylindrical portion 86d, the space between the secondannular flange portion 86c and themale screw portion 86e (the region adjacent to the secondannular flange portion 86c) is a cut-processed cylindrical surface and forms a part of the seal space SP, such that a large seal space SP formed between the receivingmember 86 and theseal recess 2c of the valvemain body 2 can be secured. Accordingly, a seal SL having a relatively large cross section (here, a rectangular cross section) can be adopted, and the sealing performance and durability of the seal can be improved. - The
stopper member 84 includes adisc portion 84a facing thediaphragm 83, a cylindricalmain body 84b connected below thedisc portion 84a, and a bag hole-shapedfitting hole 84c formed in the center of the lower surface of themain body 84b. The outer circumference of the lower surface of thedisc portion 84a is supported by the upper surface of the secondannular flange portion 86c. - The procedure for assembling the
power element 8 will be described. While placing thestopper member 84 between thediaphragm 83 and the receivingmember 86, the outer circumferential portions of theupper lid member 82, thediaphragm 83, and the receivingmember 86 are overlapped with each other, and the outer circumferential portions are circumferentially welded by, for example, TIG welding, laser welding, plasma welding, or the like to integrate them. - Subsequently, the working gas is sealed in the space (referred to as the pressure working chamber PO) surrounded by the
upper lid member 82 and thediaphragm 83 from theopening 82a formed in theupper lid member 82, and then theopening 82a is sealed with theplug 81. Further, theplug 81 is fixed to theupper lid member 82 by projection welding or the like. - At this time, since the
diaphragm 83 receives pressure in a form of projecting toward the receivingmember 86 due to the working gas sealed in the pressure working chamber PO, it is supported in contact with the upper surface of thestopper member 84 arranged in the lower space LS surrounded by thediaphragm 83 and the receivingmember 86. - When the
power element 8 assembled as described above is assembled to the valvemain body 2, themale screw portion 86e provided on the outer circumference of the lower end of the secondcylindrical portion 86d of the receivingmember 86 is screwed into thefemale screw portion 2b formed on the inner circumference of therecess 2a communicating with thereturn flow path 23 of the valvemain body 2. When themale screw portion 86e is screwed with respect to thefemale screw portion 2b, the lower end of the receivingmember 86 comes into contact with the upper end surface of the valvemain body 2. As a result, thepower element 8 can be fixed to the valvemain body 2. - At this time, the seal SL interposed in the seal space SP between the
power element 8 and the valvemain body 2 prevents the refrigerant from leaking from therecess 2a when thepower element 8 is attached to the valvemain body 2. In such a state, the lower space LS of thepower element 8 communicates with thereturn flow path 23; that is, the same internal pressure is obtained. - An example of the operation of the
expansion valve 1 will be described with reference toFIG. 1 . The refrigerant pressurized by thecompressor 101 is liquefied by thecondenser 102 and sent to theexpansion valve 1. Further, the refrigerant adiabatically expanded by theexpansion valve 1 is sent to theevaporator 104, and theevaporator 104 exchanges heat with the air flowing around the evaporator. The refrigerant returning from theevaporator 104 is returned to thecompressor 101 side through the expansion valve 1 (more specifically, the return flow path 23). At this time, by passing through theevaporator 104, the fluid pressure in thesecond flow path 22 becomes larger than the fluid pressure in thereturn flow path 23. - A high-pressure refrigerant is supplied to the
expansion valve 1 from thecondenser 102. More specifically, the high-pressure refrigerant from thecondenser 102 is supplied to the valve chamber VS via thefirst flow path 21. - When the
valve element 3 is seated on the valve seat 20 (when in the non-communicating state), the flow rate of the refrigerant sent from the valve chamber VS to theevaporator 104 through the valve through-hole 27, theintermediate chamber 221 and thesecond flow path 22 is limited. On the other hand, when thevalve element 3 is separated from the valve seat 20 (when in the communicating state), the flow rate of the refrigerant sent from the valve chamber VS to theevaporator 104 through the valve through-hole 27, theintermediate chamber 221 and thesecond flow path 22 increases. Switching between the closed state and the open state of theexpansion valve 1 is performed by theoperation rod 5 connected to thepower element 8 via thestopper member 84. - In
FIG. 1 , a pressure working chamber PO and a lower space LS partitioned by adiaphragm 83 are provided inside thepower element 8. Accordingly, when the working gas in the pressure working chamber PO is liquefied, thediaphragm 83 and thestopper member 84 rise, such that theoperation rod 5 moves upward according to the biasing force of thecoil spring 41. On the other hand, when the liquefied working gas is vaporized, thediaphragm 83 and thestopper member 84 are pressed downward, such that theoperation rod 5 moves downward. In this way, theexpansion valve 1 is switched between an open state and a closed state. - Further, the lower space LS of the
power element 8 communicates with thereturn flow path 23. Accordingly, the volume of the working gas in the pressure working chamber PO changes according to the temperature and pressure of the refrigerant flowing through thereturn flow path 23, and theoperation rod 5 is driven. In other words, in theexpansion valve 1 illustrated inFIG. 1 , the amount of the refrigerant supplied from theexpansion valve 1 toward theevaporator 104 is automatically adjusted according to the temperature and pressure of the refrigerant returning from theevaporator 104 to theexpansion valve 1. - According to this embodiment, since the
power element 8 is not miniaturized, it is not necessary to change the inner diameter of the receivingmember 86, and since the flow of the refrigerant flowing from thereturn flow path 23 into the lower space LS does not change, deterioration of the controllability of thevalve element 3 can be suppressed. It should be noted that the deterioration of the controllability means that an actual value greatly exceeds a target value or that an actual value fluctuates up or down with respect to a target value. -
FIG. 4 is an enlarged cross-sectional view illustrating the vicinity of the power element of the expansion valve according to the second embodiment.FIG. 5 is a cross-sectional view illustrating thepower element 8A of the present embodiment alone. The present embodiment differs from the above-described embodiment only in the shape of the receivingmember 86A of thepower element 8A. Since the other configurations are the same as those in the above-described embodiment, the same reference numerals are given and redundant description will be omitted. - A method of manufacturing the receiving
member 86A will be described. Similar to the embodiment described above, a metal plate material is press-molded to form a first annular flange portion 86Aa, a first cylindrical portion 86Ab, a second annular flange portion 86Ac, and a second cylindrical portion 86Ad. - Further, after the press-molding, a reduced diameter portion 86Af is formed by performing a cutting process on the boundary portion between the second annular flange portion 86Ac and the second cylindrical portion 86Ad that extend in directions orthogonal to each other. The outer diameter of the reduced diameter portion 86Af is smaller than the thread outer diameter of the male screw portion 86Ae.
- According to the present embodiment, by forming the reduced diameter portion 86Af between the second annular flange portion 86Ac and the male screw portion 86Ae, a larger seal space SP formed between the receiving
member 86A and theseal recess 2c of the valvemain body 2 can be secured. Accordingly, a seal SL having a larger cross section can be adopted, and the sealability and durability of the seal can be improved. - It should be noted that the present invention is not limited to the above-described embodiments. Within the scope of the present invention, any component of the above-described embodiments can be modified. In addition, any component can be added or omitted in the above-described embodiments.
-
- 1...
- Expansion valve
- 2...
- Valve main body
- 3...
- Valve element
- 4...
- Biasing device
- 5...
- Operation rod
- 6...
- Ring spring
- 8, 8A...
- Power element
- 20...
- Valve seat
- 21...
- First flow path
- 22...
- Second flow path
- 23...
- Return flow path
- 27...
- Valve through-hole
- 41...
- Coil spring
- 42...
- Valve element support
- 43...
- Spring receiving member
- 100...
- Refrigerant circulation system
- 101...
- Compressor
- 102...
- Condenser
- 104...
- Evaporator
- VS...
- Valve chamber
Claims (6)
- An expansion valve comprising:a valve main body;a power element mounted on the valve main body; anda seal provided between the valve main body and the power element,wherein:
the power element includes:an upper lid member;a receiving member; anda diaphragm interposed between the upper lid member and the receiving member,the receiving member is formed by press working, and includes a cylindrical portion and an annular flange portion that is adjacent to the cylindrical portion and extends in an outer circumferential direction of the cylindrical portion,the cylindrical portion of the receiving member is fixed to the valve main body, and the seal is provided in a seal space formed between the cylindrical portion, the annular flange portion, and the valve main body, anda cutting process is performed on a region of the cylindrical portion adjacent to the annular flange portion, and the region forms a part of the seal space. - The expansion valve according to claim 1, wherein:
a cutting process is performed on the cylindrical portion in parallel with an axis of the power element. - The expansion valve according to claim 1 or 2, wherein:the cylindrical portion includes a male screw portion; anda cutting process is performed on the cylindrical portion so as to form a reduced diameter portion having an outer diameter smaller than that of the male screw portion.
- The expansion valve according to any one of claim 1 to 3, wherein:a seal recess is formed in the valve main body so as to oppose the annular flange portion; anda cutting process is performed on the cylindrical portion on a radial inner side of the seal recess.
- The expansion valve according to any one of claim 1 to 4, wherein:
the cylindrical portion and the annular flange portion are bent by press molding. - A power element used in an expansion valve including:a valve main body;a power element mounted on the valve main body; anda seal provided between the valve main body and the power element,the power element comprising:an upper lid member;a receiving member; anda diaphragm interposed between the upper lid member and the receiving member, wherein:the receiving member is formed by press working, and includes a cylindrical portion and an annular flange portion that is adjacent to the cylindrical portion and extends in an outer circumferential direction of the cylindrical portion,the cylindrical portion of the receiving member is fixed to the valve main body, and the seal is provided in a seal space formed between the cylindrical portion, the annular flange portion, and the valve main body, anda cutting process is performed on a region of the cylindrical portion adjacent to the annular flange portion, and the region forms a part of the seal space.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2021055966A JP7373857B2 (en) | 2021-03-29 | 2021-03-29 | Power element and expansion valve using it |
Publications (1)
Publication Number | Publication Date |
---|---|
EP4067777A1 true EP4067777A1 (en) | 2022-10-05 |
Family
ID=80930210
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP22163460.3A Pending EP4067777A1 (en) | 2021-03-29 | 2022-03-22 | Power element and expansion valve used therein |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP4067777A1 (en) |
JP (1) | JP7373857B2 (en) |
CN (1) | CN115127260A (en) |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0867669A2 (en) * | 1997-03-27 | 1998-09-30 | Fujikoki Corporation | Expansion valve |
US20040112974A1 (en) * | 2002-12-17 | 2004-06-17 | Law Scott P. | Block valve with integral refrigerant lines |
JP2007032862A (en) * | 2005-07-22 | 2007-02-08 | Tgk Co Ltd | Expansion valve |
JP2017198373A (en) | 2016-04-26 | 2017-11-02 | 株式会社不二工機 | Expansion valve |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3130246B2 (en) * | 1995-07-13 | 2001-01-31 | 太平洋工業株式会社 | Thermal expansion valve |
JP4335713B2 (en) * | 2004-03-03 | 2009-09-30 | 株式会社不二工機 | Thermal expansion valve |
JP2006105474A (en) * | 2004-10-05 | 2006-04-20 | Tgk Co Ltd | Temperature differential type expansion valve |
JP7390699B2 (en) * | 2019-08-26 | 2023-12-04 | 株式会社不二工機 | expansion valve |
-
2021
- 2021-03-29 JP JP2021055966A patent/JP7373857B2/en active Active
-
2022
- 2022-03-22 EP EP22163460.3A patent/EP4067777A1/en active Pending
- 2022-03-28 CN CN202210311859.9A patent/CN115127260A/en active Pending
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0867669A2 (en) * | 1997-03-27 | 1998-09-30 | Fujikoki Corporation | Expansion valve |
US20040112974A1 (en) * | 2002-12-17 | 2004-06-17 | Law Scott P. | Block valve with integral refrigerant lines |
JP2007032862A (en) * | 2005-07-22 | 2007-02-08 | Tgk Co Ltd | Expansion valve |
JP2017198373A (en) | 2016-04-26 | 2017-11-02 | 株式会社不二工機 | Expansion valve |
Also Published As
Publication number | Publication date |
---|---|
JP2022152982A (en) | 2022-10-12 |
JP7373857B2 (en) | 2023-11-06 |
CN115127260A (en) | 2022-09-30 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP3076104B1 (en) | Caulking fixation type power element and expansion valve using the same | |
WO2019181409A1 (en) | Power element and expansion valve having same | |
EP4067777A1 (en) | Power element and expansion valve used therein | |
JP2024026258A (en) | Power element and expansion valve using the same | |
WO2021106933A1 (en) | Power element and expansion valve using same | |
EP4067713A1 (en) | Power element and expansion valve using same | |
WO2020189092A1 (en) | Expansion valve | |
JP7246075B2 (en) | expansion valve | |
CN114667423B (en) | Power element and expansion valve using the same | |
JP7357338B2 (en) | Power element and expansion valve using it | |
EP4063766A1 (en) | Expansion valve | |
JP7266283B2 (en) | valve device | |
JP7153912B2 (en) | expansion valve | |
WO2017170836A1 (en) | Control valve | |
JP7423165B2 (en) | capacity control valve | |
JP2022149487A (en) | Power element and expansion valve including the same | |
JP2024068727A (en) | Expansion valve | |
JP2022150662A (en) | Piping joint | |
CN115740668A (en) | Method for manufacturing power element, power element and expansion valve using power element | |
JP2022184379A (en) | expansion valve | |
JP2020139689A (en) | Expansion valve | |
JP2007051689A (en) | Differential pressure regulating valve |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION HAS BEEN PUBLISHED |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE |
|
17P | Request for examination filed |
Effective date: 20230120 |
|
RBV | Designated contracting states (corrected) |
Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |