Valve device, expansion valve, method for manufacturing a valve device, and method for manufacturing an expansion valve

Abstract

Provided are a valve device, an expansion valve, a method for manufacturing a valve device, and a method for manufacturing an expansion valve with which manufacturing costs can be reduced without increasing the number of manufacturing processes. A valve device of a valve main body includes a base surface portion which is a flat surface that is formed by subjecting one side surface of the valve main body to a prescribed cutting process or grinding process, and to which an object to be fixed can be attached, and an adjacent portion adjacent to at least a portion of an edge of the base surface portion, wherein the adjacent portion is not subjected to the prescribed cutting process or grinding process, and has a shape that does not project relative to the base surface portion in a normal line direction of the base surface portion. By having such a valve main body, the amount of material that is cut and discarded during processing is reduced, and since burrs are not formed between the base surface portion and the adjacent portion, a process to remove burrs is not required, and there is thus no increase in the number of processes.

Description

Technical Field

[0001] The present invention relates to a valve device, an expansion valve, a method for manufacturing a valve device, and a method for manufacturing an expansion valve.

Background Art

[0002] An expansion valve with an electromagnetic valve, which is one type of valve device, is applied to, for example, a refrigeration cycle having a plurality of evaporators connected in parallel, and has a function of controlling the superheat degree of the refrigerant on the outlet side of the evaporator and a function of shutting off the circuit in the refrigeration cycle.

[0003] Such an expansion valve with an electromagnetic valve (electromagnetic valve integrated expansion valve) has, as shown in Patent Documents 1 and 2, a throttle flow path for decompressing and expanding the high-pressure side refrigerant, a valve body for adjusting the opening degree of the throttle flow path, a power element for displacing the valve body, an outlet flow path for supplying the decompressed and expanded refrigerant to the evaporator, and an electromagnetic valve for opening and closing the outlet flow path.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] Here, a so-called normally closed type (normally open type) electromagnetic valve is often screwed to the valve body at two locations via a housing that holds a coil. In such a case, in order to form a good magnetic path passing through the housing and a metal attractor disposed on the valve body, it is necessary to contact the housing and the attractor.

[0006] In order to properly contact the housing and the attractor, it is necessary to sufficiently ensure the dimensional accuracy of the mounting portion of the attractor on the valve body.

[0007] The valve body is formed, for example, by extruding an aluminum alloy to create an intermediate product, which is then machined to form flow paths, holes, and other features. However, if the surface formed by extrusion molding is used as the mounting surface for the housing, it is difficult to ensure sufficient dimensional accuracy of the mounting portion. Therefore, to ensure sufficient dimensional accuracy of the mounting portion, the mounting surface is formed by machining, for example, a milling machine, on the surface formed by extrusion molding.

[0008] Generally, one side of the valve body of an expansion valve with a solenoid valve serves as the mounting surface for the solenoid valve. However, since the area of ​​one side of the valve body is larger than the area required for mounting the solenoid valve, machining the entire side of the valve body results in longer processing times and increased material waste, leading to cost problems.

[0009] In contrast, as shown in Patent Document 2, it is also possible to form a mounting surface by machining only the portion of one side of the valve body necessary for mounting the solenoid valve. However, if a locally lower mounting surface is formed on one side of the valve body by milling, for example, burrs will be generated on the stepped portion between the mounting surface and the adjacent surface on that side. While these burrs can be removed by post-processing, this leads to problems such as an increase in the number of processes and thus an increase in processing time.

[0010] The present invention has been made in view of the above problems, and aims to provide a valve device, an expansion valve, a method for manufacturing a valve device, and a method for manufacturing an expansion valve that can reduce manufacturing costs without increasing the number of manufacturing steps. [Means for solving the problem]

[0011] The valve device of the present invention is In a valve device having a valve body, One side surface of the valve body comprises a base surface portion which is a flat surface to which an object to be fixed can be attached, formed by a predetermined cutting or grinding process, and an adjacent portion which is adjacent to at least a part of the edge of the base surface portion. Of the aforementioned side surfaces, only the base surface portion is subjected to the predetermined cutting or grinding process. The adjacent portion is not subjected to the predetermined cutting or grinding process and has a shape that does not protrude from the base surface in the direction normal to the base surface. It is characterized by the following:

[0012] Book The expansion valve of the invention is, A valve body having a valve chamber, an orifice formed on the upper surface of the valve chamber, a supply-side passage communicating with the valve chamber and the outside and supplying refrigerant to the valve chamber, a discharge-side passage communicating with the orifice and the outside and discharging the refrigerant from the orifice to the outside, and a return passage for carrying the refrigerant discharged from the discharge-side passage, A valve body arranged in the valve chamber, A power element provided on the upper surface of the valve body, which generates a driving force to drive the valve body, An operating rod that transmits the driving force of the power element to the valve body, The valve body comprises an object to be fixed, which is attached to one side of the valve body, The supply-side flow path extends from the front surface of the valve body to the valve chamber. The discharge side passage extends from the back surface of the valve body to the orifice. The return channel extends from the front to the back, The discharge channel is located above the supply channel, The return channel is located above the discharge channel, The aforementioned side surface comprises a recess formed along the return channel and a base surface portion which is a flat surface to which the object to be fixed can be attached, formed by predetermined cutting or grinding processes extending from the lower end of the side surface to the recess. picture, Of the aforementioned side surfaces, only the base surface portion is subjected to the predetermined cutting or grinding process. It is characterized by the following:

[0013] The manufacturing method of the valve device of the present invention is A first step of forming an intermediate processed product of the valve body from a material, wherein one side surface of the intermediate processed product has a pre-processing base surface portion and an adjacent portion adjacent to at least a part of an edge of the pre-processing base surface portion, and the pre-processing base surface portion has a shape protruding with respect to the adjacent portion, the first step; A second step of performing cutting or grinding on the pre-processing base surface portion to form a base surface portion that is a plane capable of fixing the fixed object, and having; death, In the second step, the base surface is formed by cutting or grinding only the pre-processed base surface on one side of the intermediate workpiece so that the adjacent portion does not protrude from the base surface in the direction normal to the base surface. It is characterized by this. The method for manufacturing an expansion valve of the present invention is A valve body having a valve chamber, an orifice formed on an upper surface of the valve chamber, a supply side flow path communicating with the valve chamber and the outside and supplying a refrigerant to the valve chamber, a discharge side flow path communicating with the orifice and the outside and discharging the refrigerant from the orifice to the outside, and a return flow path through which the refrigerant discharged from the discharge side flow path flows; A valve element disposed in the valve chamber; A power element provided on an upper surface of the valve body and generating a driving force for driving the valve element; An operating rod for transmitting the driving force of the power element to the valve element; A fixed object attached to one side surface of the valve body, and comprising; For the supply side flow path, it extends from the front surface of the valve body to the valve chamber, For the discharge side flow path, it extends from the back surface of the valve body to the orifice, For the return flow path, it extends from the front surface to the back surface, The discharge side flow path is located above the supply side flow path, A method for manufacturing an expansion valve in which the return flow path is located above the discharge side flow path, A first step of forming an intermediate processed product of the valve body from a material, wherein one side surface of the intermediate processed product has a pre-processing base surface portion and an adjacent portion adjacent to at least a part of an edge of the pre-processing base surface portion, and the pre-processing base surface portion has a shape protruding with respect to the adjacent portion, the first step; A second step of performing cutting or grinding on the pre-processing base surface portion to form a base surface portion that is a plane capable of fixing the fixed object, and having; In the second step, the base surface is formed by cutting or grinding only the pre-processed base surface on one side of the intermediate workpiece so that the adjacent portion does not protrude from the base surface in the direction normal to the base surface. characterized by the following.

Advantages of the Invention

[0014] According to the present invention, it is possible to provide a valve device, an expansion valve, a method for manufacturing a valve device, and a method for manufacturing an expansion valve that can reduce manufacturing costs without increasing the number of manufacturing steps.

Brief Description of the Drawings

[0015] [Figure 1] FIG. 1 is a schematic cross-sectional view schematically showing an expansion valve with an electromagnetic valve in a first embodiment. [Figure 2] FIG. 2 is a longitudinal cross-sectional view of the expansion valve with an electromagnetic valve in a cross-section whose phase is changed by 90 degrees around the axis L with respect to FIG. 1. [Figure 3] FIG. 3 is a cross-sectional view showing the configuration of FIG. 2 cut along line A-A. [Figure 4A] FIG. 4A is a schematic diagram for explaining the manufacturing process of the valve body, and is a side view of the molded product after extrusion molding. [Figure 4B] FIG. 4B is a schematic diagram for explaining the manufacturing process of the valve body, and is a front view of the molded product after extrusion molding. [Figure 5A] FIG. 5A is a schematic diagram for explaining the manufacturing process of the valve body, and is a diagram showing the state during milling. [Figure 5B] FIG. 5B is a schematic diagram for explaining the manufacturing process of the valve body, and is a diagram showing the state during milling. [Figure 5C] FIG. 5C is a schematic diagram for explaining the manufacturing process of the valve body, and is a diagram showing the state during milling. [Figure 6A] FIG. 6A is a schematic diagram for explaining the manufacturing process of the valve body, and is a side view of the molded product after milling. [Figure 6B] FIG. 6B is a schematic diagram for explaining the manufacturing process of the valve body, and is a front view of the molded product after milling. [Figure 7] FIG. 7 is a schematic diagram for explaining the manufacturing process of the valve body, and is a diagram showing the state during machining. [Figure 8A] Figure 8A is a side view of the molded product after milling according to the modified example. [Figure 8B] Figure 8B is a side view of the molded product after milling according to the modified example. [Figure 9A] Figure 9A is a schematic diagram illustrating the manufacturing process of the molded product according to the first comparative example, and is a side view of the molded product after extrusion molding. [Figure 9B] Figure 9B is a schematic diagram illustrating the manufacturing process of the molded product according to the first comparative example, and is a front view of the molded product after extrusion molding. [Figure 10A] Figure 10A is a schematic diagram illustrating the manufacturing process of the molded product according to the first comparative example, and is a side view of the molded product after milling. [Figure 10B] Figure 10B is a schematic diagram illustrating the manufacturing process of the molded product according to the first comparative example, and is a front view of the molded product after milling. [Figure 11A] Figure 11A is a schematic diagram illustrating the manufacturing process of a molded product according to the second comparative example, and is a side view of the molded product after milling. [Figure 11B] Figure 11B is a schematic diagram illustrating the manufacturing process of a molded product according to the second comparative example, and is a front view of the molded product after milling. [Figure 12A] Figure 12A is a schematic diagram illustrating the manufacturing process of the valve body of the second embodiment, and is a side view of the molded product after extrusion molding. [Figure 12B] Figure 12B is a schematic diagram illustrating the manufacturing process of the valve body of the second embodiment, and is a front view of the molded product after extrusion molding. [Figure 13A] Figure 13A is a schematic diagram illustrating the manufacturing process of the valve body of the third embodiment, and is a side view of the molded product after extrusion molding. [Figure 13B] Figure 13B is a schematic diagram illustrating the manufacturing process of the valve body of the third embodiment, and is a front view of the molded product after extrusion molding. [Figure 14A] Figure 14A is a schematic diagram illustrating the manufacturing process of the valve body of the fourth embodiment, and is a rear view of the molded product after extrusion molding. [Figure 14B]Figure 14B is a schematic diagram illustrating the manufacturing process of the valve body of the fourth embodiment, and is a left side view of the molded product after extrusion molding. [Figure 14C] Figure 14C is a schematic diagram illustrating the manufacturing process of the valve body of the fourth embodiment, and is a front view of the molded product after extrusion molding. [Figure 15] Figure 15 is a schematic diagram illustrating the valve body of the fifth embodiment. [Modes for carrying out the invention]

[0016] (First Embodiment) Hereinafter, with reference to the drawings, a first embodiment of an expansion valve with a solenoid valve, which is one type of valve device of the present invention, will be described. The expansion valve with a solenoid valve ESV consists of an expansion valve unit 1 and a solenoid valve unit 100, but the expansion valve unit 1 and the solenoid valve unit 100 use a common valve body 2. In this embodiment, as an example, the power element 8 side relative to the valve body 2 is set as the upper side to define the vertical direction, the direction in which the valve body 2 and the solenoid valve unit 100 are aligned is defined as the width direction, and the direction in which both the vertical and width directions are defined as the front-to-back direction.

[0017] (Structure of the expansion valve unit) First, the structure of the expansion valve unit 1 of this embodiment will be described with reference to Figure 1. Figure 1 is a schematic cross-sectional view illustrating the solenoid valve-equipped expansion valve (ESV) in this embodiment. The structure of the expansion valve unit 1 in the solenoid valve-equipped expansion valve (ESV) will now be described. Let L be the axis of the valve body 2. Here, axis L refers to the center line of the operating rod 5, that is, it is parallel in the vertical direction and passes through the center of the valve chamber VS, which will be described later.

[0018] The expansion valve unit 1 comprises a valve body 2 with a valve chamber VS, a valve element 3, a biasing device 4, an operating rod 5, a ring spring 6, and a power element 8. The axis of the expansion valve unit 1 is L. The power element 8 side is positioned above the valve element 3, and the valve element 3 side is positioned below the power element 8.

[0019] The valve body 2 includes a valve chamber VS, a first flow path 21, a second flow path 22, and a return flow path 23 extending from the front to the back of the valve body 2. The first flow path 21 is a supply-side flow path extending from the front of the valve body 2 to the valve chamber VS, and refrigerant (also called fluid) is supplied to the valve chamber VS via the supply-side flow path. The second flow path 22, together with the intermediate passage 221, constitutes a discharge-side flow path extending from the back of the valve body 2 to the operating rod insertion hole 27, and the fluid in the valve chamber VS is discharged to the outside of the expansion valve via the operating rod insertion hole (orifice) 27 and the discharge-side flow path. Here, the discharge-side flow path is located above the supply-side flow path, and the return flow path is located above the discharge-side flow path. The first flow path 21 and the valve chamber VS are in communication via the high-pressure side flow path 112 and the low-pressure side flow path 113 (Figure 3), which will be described later.

[0020] The valve body 2 comprises an upper surface UL, a lower surface LL, a front surface FTL, a rear surface BTL, a left side surface LTL, and a right side surface RTL. The valve body 2 is made of metal, for example.

[0021] The upper surface UL and lower surface LL are formed, for example, on planes perpendicular to the vertical direction. The front surface FTL and rear surface BTL are formed, for example, on planes perpendicular to the front-to-back direction.

[0022] The left side LTL is an example of one side to which the solenoid valve unit 100 is fixed. One side is one of the outer surfaces of the valve body 2 that is aligned with the axis of the valve body 2. The left side LTL has a first surface PL1 (base surface), a second surface PL2 (adjacent surface), and a third surface PL3 (another planar surface). As will be described in detail later, the left side LTL includes a recess D formed along the return flow path 23, and a first surface PL1 which is a planar surface to which an object to be fixed can be attached, formed by predetermined cutting or grinding processes extending from the lower end of the left side LTL to the recess D.

[0023] The first surface portion PL1 is formed on the left side LTL as a plane, within the area where the solenoid valve unit 100 can be mounted. The area required for mounting the solenoid valve unit 100 is smaller than the area of ​​the left side LTL. The first surface portion PL1 is formed, for example, on a plane perpendicular to the width direction. The first surface portion PL1 is, for example, facing the valve chamber VS in the width direction, and is formed on the left side LTL in the vertical direction from the middle to the bottom. The first surface portion PL1 is formed by machining in order to ensure sufficient dimensional accuracy of the circular opening 114, which is the mounting portion for the solenoid valve unit 100.

[0024] The second surface PL2 is an adjacent surface to the first surface PL1. The second surface PL2 is a surface located on the inner side of the valve body 2 in the direction normal to the first surface PL1. In other words, a surface located on the inner side of the valve body 2 in the direction normal to the first surface PL1 is a surface located on the center side of the valve body 2 than the first surface PL1. In other words, a surface located on the inner side of the valve body 2 in the direction normal to the first surface PL1 is a surface that is lower than the first surface PL1.

[0025] In this embodiment, the second surface PL2 is the surface of the recess D along the return flow path 23, which will be described later. This recess D extends linearly from the front FTL to the back BTL of the valve body 2. That is, the cross-sectional shape of the recess D shown in Figure 2 is substantially the same from the front FTL to the back BTL of the valve body 2.

[0026] The length of the edge of the second surface PL2 on the side of the first surface PL1 is set to be greater than or equal to the length of the edge of the first surface PL1 on the side of the second surface PL2. By setting the length of the edge of the second surface PL2 on the side of the first surface PL1 to be greater than or equal to the length of the edge of the first surface PL1 on the side of the second surface PL2, when viewing the left side LTL from below upward, the first surface PL1 is included within the second surface PL2. In this embodiment, since both the first surface PL1 and the second surface PL2 are formed from the front FTL to the back BTL, the edge of the second surface PL2 on the side of the first surface PL1 is the same length as the edge of the first surface PL1 on the side of the second surface PL2.

[0027] The surface roughness of the second surface PL2 differs from that of the first surface PL1. In this embodiment, average roughness is used as an example of surface roughness.

[0028] In this embodiment, the recess D is formed by extrusion molding, so the second surface PL2 is a surface formed by extrusion molding. The first surface PL1 is a surface formed by milling, which is an example of cutting. Thus, the first surface PL1 and the second surface PL2 have different surface roughnesses because they are formed by different methods.

[0029] Depending on the method for forming the first surface PL1 and the method for forming the second surface PL2, the surface roughness of the second surface PL2 may be greater than that of the first surface PL1, or the surface roughness of the second surface PL2 may be smaller than that of the first surface PL1.

[0030] The third surface PL3 is formed on the same plane as, or substantially the same plane as, the first surface PL1. "Formed on the same plane" means that the third surface PL3 and the first surface PL1 are included in a common plane (called a virtual plane) that is virtually formed in three-dimensional space. Here, substantially the same plane is not limited to being completely identical, but rather, as will be described later, it is a plane that allows the valve body 2 to be stably gripped across the first surface PL1 and the third surface PL3 when the valve body 2 is gripped by the chuck CK. Thus, the third surface PL3 may be, for example, a plane that is slightly higher than the first surface PL1 in the direction normal to the first surface PL1, or a plane that is slightly lower than the first surface PL1 in the direction normal to the first surface PL1. Alternatively, the third surface PL3 may be a plane that is slightly inclined with respect to the first surface PL1. Alternatively, the third surface PL3 may be a curved surface.

[0031] The right side RTL is formed as a surface that can be contacted when the valve body 2 is clamped by the chuck CK. The right side RTL has, for example, a fourth surface PL4 adjacent to the upper surface UL and a sixth surface PL6 formed at an intermediate position in the vertical direction. The fourth surface PL4 and the sixth surface PL6 are formed on surfaces that the chuck CK can contact across the fourth surface PL4 and the sixth surface PL6. The fourth surface PL4 and the sixth surface PL6 are formed, for example, on the same plane perpendicular to the width direction.

[0032] A recess D is formed between the fourth surface PL4 and the sixth surface PL6, indented toward the return flow path 23, and its surface is designated as the fifth surface PL5. Here, the fifth surface PL5, adjacent to the fourth surface PL4 and the sixth surface PL6, is a curved surface and is either tangent to a virtual plane passing through the fourth surface PL4 and the sixth surface PL6, or is located in a direction closer to the center of the valve body 2 than that plane.

[0033] Between the sixth surface PL6 and the lower surface LL, the seventh surface PL7 is formed, which is located on the inner side of the valve body 2 than the sixth surface PL6. The fourth surface PL4 to the seventh surface PL7 constitute the right side RTL.

[0034] The spherical valve body 3 is positioned within the valve chamber VS. When the valve body 3 is seated on the annular valve seat 20 of the valve body 2, the valve chamber VS and the second flow path 22 are not in communication. On the other hand, when the valve body 3 is separated from the valve seat 20, the valve chamber VS and the second flow path 22 are in communication.

[0035] The lower end of the operating rod 5, which is inserted with a gap into the operating rod insertion hole 27, is in contact with the upper surface of the valve body 3. The operating rod 5 can also press the valve body 3 in the opening direction against the biasing force of the biasing device 4. When the operating rod 5 moves toward the valve body, the valve body 3 separates from the valve seat 20, and the expansion valve unit 1 opens.

[0036] The operating rod 5 extends along its axis L from the valve body 3 to the power element 8 via an operating rod insertion hole 27, a central hole 28, an annular portion 26, a return passage 23, and a communication passage 2b, all coaxially formed in the valve body 2. The inner diameter of the annular portion 26 is set to be larger than the inner diameter of the central hole 28, which slidably holds the operating rod 5. An operating rod vibration damping spring 6, which has a vibration damping function for the operating rod 5, is arranged in the annular portion 26.

[0037] The operating rod vibration damping spring 6 is described in detail in, for example, Japanese Patent Publication No. 2018-25332, so its explanation is omitted here.

[0038] Next, the power element 8 will be described. The power element 8 is attached to a recess 2a provided at the top of the valve body 2. The recess 2a communicates with the return passage 23 inside the valve body 2 through a communication passage 2b, through which the refrigerant from the evaporator passes.

[0039] The power element 8 includes a plug 81, an upper cover member 82, a diaphragm 83, a stopper member 84, and a receiving member 86.

[0040] A hole 82a is formed at the top of the upper lid member 82, and the hole 82a can be sealed by a plug 81.

[0041] The diaphragm 83 is made of a thin plate material with multiple concentric circular indentations formed on it.

[0042] The stopper member 84 has a disc portion and a cylindrical portion coaxially connected to the lower surface of the disc portion, and a fitting hole 84c is formed in the center of the lower end of the cylindrical portion.

[0043] The receiving member 86 has a flange portion having an outer diameter approximately the same as that of the upper cover member 82, and a hollow cylindrical portion connected to the lower end of the flange portion, with a male thread 86c formed on the outer circumference of the hollow cylindrical portion.

[0044] During the assembly of the power element 8, the outer periphery of the upper cover member 82, the diaphragm 83, and the flange portion of the receiving member 86 are first overlapped, and these outer periphery portions are then integrated by circumferential welding, such as TIG welding, laser welding, or plasma welding.

[0045] Next, after sealing the working gas into the space enclosed by the upper cover member 82 and the diaphragm 83 (called the pressure working chamber PA) through the hole 82a formed in the upper cover member 82, the hole 82a is sealed with a plug 81, and the plug 81 is then fixed to the upper cover member 82, for example, by projection welding.

[0046] At this time, the diaphragm 83 is subjected to pressure by the working gas sealed in the pressure working chamber PA, causing it to protrude towards the receiving member 86. As a result, it is supported by contacting the upper surface of the stopper member 84, which is located in the lower space LS surrounded by the diaphragm 83 and the receiving member 86. Since the disc portion of the stopper member 84 is held by the receiving member 86, the stopper member 84 will not come out of the power element 8.

[0047] When assembling the power element 8 to the valve body 2, with the upper end of the operating rod 5 fitted into the fitting hole 84c of the stopper member 84, the operating rod 5 is inserted into the valve body 2 while passing through the operating rod vibration damping spring 6 that is assembled to the valve body 2. Furthermore, the power element 8 is fixed to the valve body 2 by screwing the male thread 86c of the receiving member 86 into the female thread of the recess 2a of the valve body 2. In this state, the lower space LS of the power element 8 is in communication with the return passage 23, so the internal pressure of the lower space L becomes the same as the internal pressure of the return passage 23.

[0048] Next, the biasing device 4 will be described. In Figure 1, the biasing device 4 includes a coil spring 41 made by winding a circular wire spirally, a valve body support 42 attached to the upper end of the coil spring 41 to support the valve body 3, and a spring receiving member 43 attached to the valve body 2 while supporting the lower end of the coil spring 41. The spring receiving member 43 has the function of sealing the valve chamber VS of the valve body 2 and supporting the end of the coil spring 41 that biases the valve body 3 toward the valve seat 20.

[0049] A spherical valve body 3 is welded to the upper surface of the valve body support 42, and the valve body support 42 and the valve body 3 are integrated into one unit.

[0050] (Structure of the solenoid valve unit) Next, with reference to Figures 2 and 3, the structure of the solenoid valve unit (also simply called a solenoid valve) 100 of this embodiment will be described. The solenoid valve unit 100 is an example of an object to be fixed to the valve body 2. Figure 2 is a longitudinal cross-sectional view of an expansion valve (ESV) with a solenoid valve, in a cross-section where the phase is shifted by 90 degrees around axis L compared to Figure 1. Figure 3 is a bottom view of the configuration in Figure 2, cut along line AA, but the coil spring 41, valve support 42, valve body 3, and operating rod 5 are omitted from the illustration. The axis of the solenoid valve unit 100 is denoted as O.

[0051] As shown in Figures 2 and 3, the solenoid valve unit 100 includes a valve body 2, an suction element 140, a plunger 150, a pilot valve body 160, a main valve body 170, and a coil unit 180.

[0052] The valve body 2 contains a high-pressure side passage 112 (Figure 3) connected to the first passage 21, a low-pressure side passage 113 connected to the valve chamber VS, and a circular opening 114 communicating with the high-pressure side passage 112 and the low-pressure side passage 113. A cylindrical portion 113a, which forms the low-pressure side passage 113 on its inner side, protrudes coaxially into the circular opening 114. The tip of the cylindrical portion 113a becomes the main valve seat 113b.

[0053] The first surface (base surface) PL1, which forms part of one side of the valve body 2, is a plane perpendicular to the axis O. A circular opening 114 is formed coaxially with the axis O in the first surface PL1. Although not shown, a screw hole is formed in the first surface PL1.

[0054] A suction element 140 is installed within the circular opening 114. The suction element 140 has a disc-shaped base 141 and a shaft 142 with a smaller diameter than the base 141, and the base 141 and shaft 142 are connected coaxially. The base 141 has a circular opening 141a formed in the center of the end on the valve body side. A guide hole 141b is formed that spans the base 141 and the shaft 142 in the axial direction and communicates with the center of the opening 141a.

[0055] Within the opening 141a, the main valve body 170 is slidably positioned along the axis O. The valve body side end face of the main valve body 170 is seatable on the main valve seat 113b of the cylindrical portion 113a. A pilot valve port 171 is formed in the center of the main valve body 170, penetrating parallel to the axis O, and a pressure equalization passage is formed adjacent to the pilot valve port 171, penetrating along the axis O. The main valve body 170 is biased toward the shaft portion 142 side relative to the base portion 141 of the suction element 140 by a spring 173.

[0056] The male threads formed on the outer circumference of the base 141 are screwed into the female threads on the inner circumference of the circular opening 114, thereby fixing the suction element 140 to the valve body 2 while its outer circumference abuts against the inner circumferential step of the circular opening 114. At this time, an O-ring is placed between the base 141 and the circular opening 114. The O-ring prevents fluid from leaking through the gap between the base 141 and the circular opening 114.

[0057] With the base portion 141 attached to the circular opening 114, the shaft portion 142 protrudes in a direction perpendicular to the mounting surface (first surface portion PL1). Near the end of the shaft portion 142, the end of a thin-walled, top-cylindrical can member 144 is joined coaxially with the shaft portion 142 by welding or brazing. Inside the can member 144 are a plunger 150 and a pilot valve body 160.

[0058] The plunger 150, which has a hollow cylindrical shape, is arranged to slide relative to the can member 144 in the axial direction O. The cylindrical pilot valve body 160 consists of a head 161, a body 162 with a smaller diameter than the head 161, and a tapered portion 163 formed at the end of the body 162.

[0059] With the pilot valve body 160 assembled inside the plunger 150, the head 161 is locked to the reduced diameter portion of the inner circumference of the end of the plunger 150, thereby holding the pilot valve body 160 relative to the plunger 150. In this state, the body portion 162 of the pilot valve body 160 protrudes from the plunger 150 toward the valve body, and the body portion 162 is inserted through the guide hole 141b of the shaft portion 142 of the suction element 140. Furthermore, the tapered portion 163 protrudes into the opening 141a and faces the pilot valve port 171 of the main valve body 170.

[0060] A spring 151 is positioned between the top of the can member 144 and the head of the pilot valve body 160. The spring 151 biases the pilot valve body 160 toward the valve body. Additionally, an intermediate spring 152 is positioned between the shaft portion 142 and the end of the plunger 150. The intermediate spring 152 biases the plunger 150 toward the side away from the valve body.

[0061] In Figures 2 and 3, the coil unit 180 includes a hollow cylindrical electromagnetic coil 181 and a housing 182 that holds the electromagnetic coil 181.

[0062] As shown in Figure 3, the housing 182 is formed by press-forming two metal plates arranged approximately parallel to each other and connecting their opposing edges with another metal plate to create a shape (approximately U-shaped).

[0063] With the solenoid valve unit 100 assembled, the electromagnetic coil 181 is located radially outward of the plunger 150, with the can member 144 in between.

[0064] (Manufacturing process of the valve body) The manufacturing process for valve body 2 will be explained. Figures 4A to 47 are schematic diagrams illustrating the manufacturing process of the valve body 2. The manufacturing process consists of a first step, a second step, and a third step.

[0065] [Step 1] The first step is to form a molded product MA, which is an intermediate product of the valve body 3. First, a long object is formed by extruding a material, such as an aluminum alloy, and then the long object is cut parallel to each other at predetermined intervals to form a molded product MA as shown in Figures 4A and 4B. The molded product MA may have an opening OP (corresponding to the return channel 23) formed along the molding direction.

[0066] Here, in the molded product MA, the molding direction is defined as the X direction, and the directions perpendicular to the X direction are defined as the Y direction and the Z direction. The Y direction and the Z direction are mutually orthogonal.

[0067] The X direction corresponds to the front-to-back direction of the valve body 2, the Y direction corresponds to the width direction of the valve body 2, and the Z direction corresponds to the up-and-down direction of the valve body 2. The upper surface UL and lower surface LL of the molded product MA shall extend parallel to the XY plane, which is a plane perpendicular to the Z direction, for example. In addition, the front surface FTL and back surface BTL (overlapping with the front surface FTL) of the molded product MA shall extend parallel to the YZ plane, which is a plane perpendicular to the X direction, for example.

[0068] The molded product MA comprises an upper surface UL, a lower surface LL, a front surface FTL, a back surface BTL, a left side LTL1 before processing, and a right side RTL. In other words, in this embodiment, the outer surface of the valve body 2, excluding the left side LTL, is formed by extrusion molding.

[0069] The left side LTL1 of the molded product MA formed by extrusion molding has a first surface portion (pre-processing base surface portion) PL11 adjacent to the bottom surface LL and a third surface portion PL3 adjacent to the top surface UL. The first surface portion PL11 and the third surface portion PL3, which are both planar surfaces, are formed parallel to the ZX plane perpendicular to the Y direction, and the first surface portion PL11 is shifted in the direction away from the center of the molded product MA by a distance Δ in the direction (-Y direction) relative to the third surface portion PL3 in the direction of its normal vector. Note that the first surface portion PL11 does not necessarily need to be parallel to the third surface portion PL3 after extrusion molding, as it will be subjected to machining as described later.

[0070] By extrusion molding, a recess D (which may also serve as a material removal area) is formed between the first surface PL11 and the third surface PL3 before processing, and its surface is designated as the second surface PL2. Here, the second surface (adjacent part) PL2 adjacent to the first surface PL11 and the third surface PL3 before processing is a curved surface and is located in a direction (+Y direction) that is closer to the center of the molded product MA than the first surface PL1 (see Figures 2 and 3). Preferably, at least a portion of the second surface PL2 is located at the same position as the third surface PL3 in the normal direction of the first surface PL1, or in a direction (+Y direction) that is closer to the center of the molded product MA than the third surface PL3.

[0071] The right side RTL of the molded product MA has a fourth surface PL4 adjacent to the top surface UL and a sixth surface PL6 formed at an intermediate position on the molded product MA. The fourth surface PL4 and the sixth surface PL6 are formed parallel to the ZX plane and within a common virtual plane.

[0072] A recess D is formed between the fourth surface PL4 and the sixth surface PL6, indented toward the opening OP, and its surface is designated as the fifth surface PL5. Here, the fifth surface PL5, adjacent to the fourth surface PL4 and the sixth surface PL6, is a curved surface and is either tangent to a virtual plane passing through the fourth surface PL4 and the sixth surface PL6, or exists in a direction (-Y direction) closer to the molded product MA.

[0073] Between the sixth surface PL6 and the bottom surface LL, the seventh surface PL7 is formed, located in a direction (-Y direction) closer to the left side LTL1 before machining than the sixth surface PL6. The fourth surface PL4 to the seventh surface PL7 constitute the right side RTL.

[0074] Before processing, the left side LTL1, right side RTL, top surface UL, and bottom surface LL of the molded product MA have lines STR formed at uneven intervals and parallel to each other along the molding direction on the surfaces that come into contact with the mold (not shown). The first surface PL11 before processing, where the lines STR are formed, is not suitable as the surface to which the housing 182 of the solenoid valve unit 100 is attached. Therefore, the dimensional accuracy of the circular opening 114 is improved by performing milling, an example of cutting, on the first surface PL11 before processing after extrusion molding.

[0075] [Step 2] The second step is to perform machining on the first surface portion PL11 of the left side LTL1 before machining to form a first surface portion PL1 on which the solenoid valve unit 100 can be fixed. More specifically, as shown in Figure 5A, the molded part MA is fixed so that the left side LTL1 before machining is exposed, and the rotating milling tool FT is brought towards the molded part MA from the lower side LL in the +Z direction. At this time, the lower end of the cutting edge is assumed to rotate in the ZX plane. The molded part MA is fixed by, for example, clamping the front FL and back BTL with a chuck CK. Fixing the molded part MA is not limited to a chuck. In other examples, the molded part MA may be fixed with adhesive.

[0076] Furthermore, the lower end of the cutting edge of the milling tool FT is positioned in the +Y direction by a distance Δ relative to the first surface PL11 before machining, and the milling tool FT is moved in the +Z direction as shown in Figure 5B. While cutting away the entire first surface PL11 before machining, the milling tool FT is moved to a position where the cutting edge reaches the second surface PL2 (but not the third surface PL3), as shown in Figure 5C. As a result, a portion of the first surface PL11 and the second surface PL2 before machining are cut away, and the first surface PL1 is created on the left side LTL of the molded product MA. The first surface PL1 is formed on the same plane as, or approximately the same plane as, the third surface (another plane) PL3 (see Figure 6B). In its normal direction, the first surface PL1 is shifted away from the center of the molded product MA (-Y direction) relative to the second surface PL2.

[0077] As shown in Figure 6A, tool marks TM are formed on the first surface PL1, which is the cutting surface, by milling, corresponding to the rotational trajectory of the cutting edge. Therefore, the flatness and dimensional accuracy of the first surface PL1 can be improved compared to the flatness and average surface roughness of the second surface PL2 and third surface PL3, where the markings STR are formed. The average surface roughness of the first surface PL1 is different from the average surface roughness of the second surface PL2 and third surface PL3. Here, "average surface roughness" refers to the arithmetic mean roughness Ra as defined in JIS and ISO standards.

[0078] Furthermore, the fixing of the molded product MA when milling the first surface PL1 is not limited to fixing using a chuck CK, as long as the fixing does not interfere with the machining process. Examples of fixing without using a chuck CK include adhesive or suction. Preferably, the adhesive / suction points of the molded product MA are in positions that do not interfere with post-processing.

[0079] [Third step] The third step is to form the valve body 2 from the molded product MA by applying processing to the molded product MA other than the processing performed in the first and second steps. After removing the molded product MA from the chuck CK, the molded product MA is re-fixed so that the surface to be processed in the next process is exposed. More specifically, as shown in Figure 7, the flat surface of one chuck CK1 is brought into contact with the first surface PL1 and the third surface PL3, and the flat surface of the other chuck CK2 is brought into contact with the fourth surface PL4 and the sixth surface PL6. The first surface PL1 and the third surface PL3 exist in a common virtual plane, and the fourth surface PL4 and the sixth surface PL6 also exist in a common virtual plane, and furthermore, the two virtual planes are parallel, so the molded product MA can be stably fixed by the chucks CK1 and CK2.

[0080] With the molded product MA fixed by chucks CK1 and CK2, machining is performed from the front FTL side or the back BTL side of the molded product MA, as shown by the dotted lines, to create the first flow path 21, the return passage 23 around the opening OP, the second flow path 22 (Figure 1), the intermediate passage 221 (Figure 1), and the screw holes 2e and mounting holes 2f used when attaching the solenoid valve expansion valve ESV to other components. In addition, although not shown in Figure 7, machining is performed from the upper UL side or the lower LL side to create the recess 2a for attaching the power element 8, the connecting passage 2b, the annular portion 26, the central hole 28, the operating rod insertion hole 27, the valve chamber VS, etc. After that, screw holes are formed in the first surface PL1. The valve body 2 is manufactured by machining the molded product MA in this way.

[0081] By assembling the above-mentioned parts onto the valve body 2, the solenoid valve-equipped expansion valve (ESV) is completed.

[0082] Milling is not limited to the embodiments described above. For example, the milling tool FT may be rotated and moved in the X direction relative to the molded product MA, thereby forming tool marks TM with a trajectory as shown in Figure 8A. Alternatively, the milling tool FT, which has a small diameter cutting edge, may be rotated and moved back and forth in the Z direction relative to the molded product MA, thereby forming a large area first surface PL1 even with a small milling tool FR. On such first surface PL1, multiple rows (two rows in this case) of tool marks TM are formed, for example, as shown in Figure 8B.

[0083] (Comparative example) The manufacturing process for the valve body molded products MA1 and MA2 in the comparative example will be described. Figures 9A to 911B are schematic diagrams illustrating the manufacturing process of molded products MA1 and MA2, with the XYZ directions being the same as those used in the embodiment described above.

[0084] In this comparative example as well, a long object is formed by extruding a material, such as an aluminum alloy, and then the long object is cut parallel to each other at predetermined intervals to form the molded product MA1 as shown in Figures 9A and 9B. However, the left side LTL1 of the molded product MA1 is a single plane except for the joint between the upper surface UL and the lower surface LL. The right side RTL of the molded product MA1 has the same shape as in the embodiment described above.

[0085] A slit STR is formed across the entire left side LTL1. By milling the entire left side LTL11 before processing, a cut surface CPL1 can be formed, as shown in Figures 10A and 10B. This ensures flatness and sufficient dimensional accuracy on the cut surface CPL1 across the entire left side LTL1, making it suitable as the mounting surface for the housing 182 of the solenoid valve unit 100. However, this increases the amount of material removed and discarded by milling, and also increases processing time, resulting in increased manufacturing costs. Furthermore, since the area where the housing 182 of the solenoid valve unit 100 is mounted is only a part of the left side LTL1, it is not necessary to mill the entire left side LTL1.

[0086] Alternatively, a portion of the left side can be milled and removed. Figures 11A and 11B show a molded product MA2, as another comparative example, in which only the lower part of the left side LTL2 is milled to form a cut surface CPL2, compared to the extruded molded product shown in Figures 9A and 9B. Molded product MA2 has the advantage of reducing the amount of material removed and discarded by milling, and also shortening the processing time. However, a step STP is formed between the milled cut surface CPL2 and the left side LTL2 that was not milled, and burrs and other debris are generated on the upper edge EG of the step STP, requiring a step to remove them, which is time-consuming.

[0087] In contrast, according to this embodiment, as shown in Figures 4A and 4B, a second surface portion PL2 is formed between the first surface portion PL11 and the third surface portion PL3 of the molded product MA immediately after extrusion molding. This second surface portion PL2 is lower than the first surface portion PL11 (located in the direction closer to the center of the molded product MA (+Y direction)). Therefore, even if a portion of the first surface portion PL11 and the second surface portion PL2 are removed by milling, the remainder of the second surface portion PL2 is not removed, reducing the amount of material that is removed and discarded, and also shortening the processing time, thus reducing manufacturing costs. Furthermore, the generation of burrs between the first surface portion PL1 and the second surface portion PL2 is suppressed. In other words, manufacturing costs can be reduced without increasing the number of processes.

[0088] Furthermore, by forming the third surface PL3 on the same plane or substantially the same plane as the first surface PL1, the first surface PL1 and the third surface PL3 can be clamped by the chuck CK during subsequent machining processes, thereby improving manufacturing efficiency.

[0089] In this way, by attaching the solenoid valve unit 100 to the machined first surface PL1, the housing 182 and the suction element 140 can be brought into close contact, and a good magnetic path is formed when the solenoid valve unit 100 is in operation.

[0090] (Second embodiment) The shape of the molded valve body is not necessarily limited to the shape of the embodiment described above. In the first embodiment, an example was described in which the second surface PL2 is formed on a surface located on the inner side of the valve body 2 in the direction normal to the first surface PL1. However, for example, the second surface PL2 may be formed on a plane that is at the same position as the first surface PL1 in the direction normal to the first surface PL1, or on a plane that is substantially the same. This example will be explained using Figures 12A and 12B. In Figure 12B, the first surface PL1 is shown by a dashed line, and an example is shown in which the second surface PL2 is on a plane substantially the same as the first surface PL1.

[0091] Here, "approximately identical planes" is not limited to being completely identical planes, but rather refers to planes that enable stable clamping of the valve body 2 across the first surface PL1 and the second surface PL2 when the valve body 2 is clamped by the chuck CK. Thus, the second surface PL2 may, for example, be a plane that is slightly lower than the first surface PL1 in the direction normal to the first surface PL1. Alternatively, the second surface PL2 may be a plane that is slightly inclined with respect to the first surface PL1. Alternatively, the second surface PL2 may be a curved surface.

[0092] Thus, in this embodiment, the second surface PL2 can also be used as the third surface described in relation to the first embodiment. That is, the second surface PL2 can be used as the surface to be chucked by the chuck CK.

[0093] In the second embodiment shown in Figures 12A and 12B, the left side LTL3 of the molded product MA3 before processing after extrusion molding may include a first surface PL11, a second surface PL2, and a slope (a second surface which is a plane) SL connecting the first surface PL11 and the second surface PL2. The first surface PL11 is formed on a surface shifted in the direction away from the center of the molded product MA (-Y direction) relative to the second surface PL2. For example, the first surface PL11 is formed on a plane parallel to the second surface PL2. The right side RTL3 of the molded product MA3 is, for example, a planar shape. Lines are not shown in the illustration.

[0094] By performing a cutting process, such as milling, on the first surface PL1 of the molded product MA3 before processing, a first surface PL1 is formed that is coplanar or substantially coplanar with the second surface PL2, as shown by the dashed line. In this case, the second surface PL2 becomes the adjacent surface adjacent to the mounting surface (base surface). As a result, the first surface PL1 can be formed into a plane with sufficient dimensional accuracy to serve as the mounting surface for the housing 182 of the solenoid valve unit 100. Furthermore, compared to the case where the entire left side surface LTL3 is milled, the amount of material that is cut off and discarded is reduced, and the processing time is also shortened. In addition, the generation of burrs between the first surface PL1 and the second surface PL2 is suppressed.

[0095] (Third embodiment) Furthermore, in the first embodiment, an example was described in which the molded product MA is formed by extrusion molding and the recess D is formed by extrusion molding. However, the recess D may also be formed by machining the molded product MA. This example will be explained using Figures 13A and 13B.

[0096] In the third embodiment shown in Figures 13A and 13B, a straight groove SGV, which is a modified example of the recess D, may be formed on the left side LTL4 of the molded product MA4 after extrusion molding, between the first surface PL11 and the third surface PL3 before processing. The first surface PL11 before processing is parallel to the third surface PL3 and is formed on a surface that is shifted in the direction away from the center of the molded product MA (-Y direction) relative to the third surface PL1. For example, the first surface PL11 before processing is formed on a plane parallel to the third surface PL3. The right side RTL4 of the molded product MA4 is planar. The lines are not shown.

[0097] By milling the molded part MA4, a first surface PL1 is formed that is flush with the third surface PL1, as shown by the dotted line. Here, the surface of the remaining straight groove SGV becomes the adjacent surface adjacent to the mounting surface (base surface). This allows the first surface PL1 to be formed as a plane with sufficient dimensional accuracy to serve as the mounting surface for the housing 182 of the solenoid valve unit 100. Furthermore, compared to milling the entire left side surface LTL4, the amount of material that is cut off and discarded is reduced, and the processing time is also shortened. In addition, the generation of burrs between the first surface PL1 and the straight groove SGV can be suppressed.

[0098] (Fourth embodiment) Furthermore, in the first and third embodiments, examples were described in which the recess D or straight groove SG having the second surface portion PL2 is formed in a straight line. However, the shape of the recess D or straight groove SG having the second surface portion PL2 is set according to the first surface portion PL1. For example, the recess may be formed in a curved shape in plan view, or it may be formed in a shape in which a plurality of straight portions are connected in plan view. Moreover, in the first and third embodiments, examples were described in which the recess having the second surface portion PL2 is connected to a pair of opposing edges on the left side surface LTL of the valve body 2. However, in other examples, the recess having the second surface portion PL2 may be connected to two adjacent edges on the side surface of the valve body 2.

[0099] These multiple modifications will be explained using Figures 14A, 14B, and 14C. The molded product MA5 according to the fourth embodiment shown in Figures 14A, 14B, and 14C can be formed, for example, by forging. More specifically, the left side LTL5 of the molded product MA5 has a third surface PL3 with an L-shaped plane and a rectangular pre-processed first surface PL11, and an L-shaped groove LGV is formed between the pre-processed first surface PL11 and the third surface PL3, extending in two directions (X direction and Y direction) while bending at a right angle. The first surface PL1 is parallel to the third surface PL3 and is formed on a surface that is shifted in the direction away from the center of the molded product MA (-Y direction) relative to the third surface PL1. The pre-processed first surface PL11 is formed, for example, on a plane parallel to the third surface PL3. Note that the molded product MA5 is not limited to forging, but can also be formed by casting, die casting, or other processes using a mold. The drawing is omitted from the diagram.

[0100] By performing milling, an example of cutting, on the first surface PL11 before processing, the first surface PL1 is formed to be coplanar with the third surface PL1, as shown by the dotted line. Here, the surface of the remaining L-shaped groove LGV becomes the adjacent surface adjacent to the mounting surface (base surface). In this embodiment as well, by performing cutting on the first surface PL11 before processing, the first surface Pl1 can be formed into a plane with sufficient dimensional accuracy to serve as the mounting surface for the housing 182 of the solenoid valve unit 100. Furthermore, compared to the case where milling is performed on the entire left side LTL5, the amount of material that is cut off and discarded is reduced, and the processing time is also shortened. In addition, the generation of burrs between the first surface PL1 and the L-shaped groove LGV can be suppressed.

[0101] (Fifth embodiment) In the first, third, and fourth embodiments, an example was described in which the valve body 2 has a first surface portion PL1, a second surface portion PL2, and a third surface portion PL3. In the second embodiment, an example was described in which the valve body 2 has a first surface portion PL1 and a second surface portion PL2 but no third surface portion PL3, and the second surface portion PL2 is formed on a plane that is in the same position as or substantially the same as the first surface portion PL1 in the direction normal to the first surface portion PL1. In other examples, as in the fifth embodiment shown in Figure 15, the valve body 2 has a first surface portion PL1 and a second surface portion PL2 but no third surface portion PL3, and the second surface portion PL2 may be a plane that is located on the inner side of the valve body 2 relative to the first surface portion PL1 in the direction normal to the first surface portion PL1. In this example, the left side LTL has a first surface PL1 and a second surface PL2, the second surface PL2 being formed on a surface that is inclined inward relative to the first surface PL1 and along the normal direction of the first surface PL1. The method of forming the second surface PL2 is not limited. The second surface PL2 may be formed, for example, by extrusion molding.

[0102] Furthermore, in the first to fifth embodiments, an example was described in which the first surface portion PL1 is separated by the edge of the left side surface LTL and a recess D having the second surface portion PL2. However, in other examples, the recess having the second surface portion PL2 may be formed in an annular shape, and the first surface portion PL1 may be surrounded by the recess. The annular shape of the recess having the second surface portion PL2 is not limited and may be a circular or rectangular annular shape.

[0103] (Operation of the expansion valve) Referring to Figure 1, an example of operation when an expansion valve with a solenoid valve (ESV) is incorporated into a refrigeration cycle will be described. The refrigerant pressurized by the compressor is liquefied in the condenser of the refrigeration cycle and sent to the expansion valve unit 1. The refrigerant adiabatically expanded in the expansion valve unit 1 is then sent to the evaporator of the refrigeration cycle, where it exchanges heat with the air flowing around the evaporator. The refrigerant returning from the evaporator is returned to the compressor side through the expansion valve unit 1 (more specifically, the return passage 23). At this time, after passing through the evaporator, the fluid pressure in the second passage 22 becomes greater than the fluid pressure in the return passage 23.

[0104] The expansion valve unit 1 is supplied with high-pressure refrigerant from the condenser 102. More specifically, the high-pressure refrigerant from the condenser 102 is supplied to the first flow path 21. Here, we assume that the solenoid valve unit 100 is in the open state. In this case, the refrigerant supplied to the first flow path 21 reaches the valve chamber VS via the high-pressure side flow path 112, the circular opening 114, and the low-pressure side flow path 113.

[0105] When the valve body 3 is seated on the valve seat 20, the first flow path 21 upstream of the valve chamber VS and the second flow path 22 downstream of the valve chamber VS are not in communication. On the other hand, when the valve body 3 is separated from the valve seat 20, the refrigerant supplied to the valve chamber VS is sent to the evaporator through the operating rod insertion hole 27 and the second flow path 22. The switching between the closed and open states of the expansion valve unit 1 is performed by the operating rod 5 connected to the power element 8.

[0106] In Figure 1, the power element 8 is provided with a pressure-operated chamber PA and a lower space LS, separated by a diaphragm 83. Therefore, when the working gas in the pressure-operated chamber PA is liquefied, the actuator 5 moves towards the diaphragm, and when the liquefied working gas is vaporized, the actuator 5 moves towards the valve body. In this way, the expansion valve unit 1 is switched between the open and closed states.

[0107] Furthermore, the lower space LS of the power element 8 is in communication with the return passage 23. Therefore, the phase (gas phase, liquid phase, etc.) of the working gas in the pressure working chamber PA changes according to the temperature and pressure of the refrigerant flowing through the return passage 23, and the working rod 5 is driven. In other words, in the expansion valve unit 1 shown in Figure 1, the amount of refrigerant supplied from the expansion valve unit 1 to the evaporator is automatically adjusted according to the temperature and pressure of the refrigerant returning from the evaporator to the expansion valve unit 1.

[0108] On the other hand, when the solenoid valve unit 100 is in the closed state, the refrigerant supplied to the first flow path 21 is blocked from being supplied from the first flow path 21 to the valve chamber VS because the communication between the circular opening 114 and the low-pressure side flow path 113 is blocked.

[0109] (On / off operation of solenoid valve) Next, the on / off valve operation of the solenoid valve unit 100 will be described. In Figures 2 and 3, when the electromagnetic coil 181 is powered from a power source (not shown), the magnetic field generated by the electromagnetic coil 181 creates a magnetic path through the plunger 150, the attractor 140, and the housing 182, generating a magnetic force that pushes the plunger 150 toward the valve body 2, against the biasing force of the intermediate spring 152. When the plunger 150 is pressed, the pilot valve body 160 moves in the same direction, closing the pilot valve port 171 of the main valve body 170 and pushing down the main valve body 170, shielding the end of the cylindrical portion 113a (main valve seat 113b). In this state, the pressure in the plunger-side space of the main valve body 170, which communicates with the high-pressure side passage 112 via the equalizing passage 172, is greater than the internal pressure of the cylindrical portion 113a, which communicates with the low-pressure side passage 113. Therefore, the main valve body 170 remains seated on the end of the cylindrical portion 113a against the biasing force of the spring, meaning the solenoid valve unit 100 is closed, and the flow of refrigerant from the high-pressure side passage 112 to the low-pressure side passage 113 is blocked.

[0110] Conversely, when the power supply from the power source (not shown) to the electromagnetic coil 181 is interrupted, the magnetic force pressing the plunger 150 toward the valve body 2 disappears, and the plunger 150 is pushed back by the intermediate spring 152. As a result, the pilot valve body 160 separates from the main valve body 170, and the pilot valve port 171 opens. This causes fluid to flow from the high-pressure side passage 112 to the low-pressure side passage 113 through the pilot valve port 171, and the internal pressure of the cylindrical portion 113a increases, causing the pressures in the axial space between the main valve body 170 to balance. Therefore, the main valve body 170 separates from the valve body 2 according to the biasing force of the spring 173, creating a gap between it and the end of the cylindrical portion 113a, and fluid flows from the high-pressure side passage 112 to the low-pressure side passage 113 through this gap.

[0111] Furthermore, the third surface P portion L3 does not necessarily have to be a flat surface; it may be a curved surface as long as it can contact the chuck CK together with the first surface PL1 and support the chuck CK. Also, the first surface PL1 may be a surface that has been subjected to other cutting processes, not just milling. As an example of the valve device of the present invention, an expansion valve with a solenoid valve having a solenoid valve unit 100 has been described, but other examples of the valve device of the present invention may be a valve device having an electric valve as the object to be fixed. Thus, the object to be fixed to the valve body is not limited to the solenoid valve unit 100, but may be other parts or other devices of the valve device. Alternatively, the object to be fixed may be a part or device other than the components of the valve device. For example, another device installed near the location where the valve device is installed may be the object to be fixed.

[0112] Furthermore, in the first to fifth embodiments, examples were described in which the second surface portion PL2 and the third surface portion PL3 of the left side LTL are formed by extrusion molding. However, in other examples, the second surface portion PL2 and the third surface portion PL3 may be subjected to processing such as polishing or cutting after being formed by extrusion molding. Similarly, the top surface UL, bottom surface LL, right side RTL, front FTL, and back BTL may be subjected to polishing or cutting after being formed by extrusion molding.

[0113] Furthermore, while the first to fifth embodiments described examples in which the processing is carried out in the order of the first, second, and third steps, the order of processing is not limited to these examples. In other examples, the third step may be performed after the first step, and the second step may be performed after the third step.

[0114] Furthermore, in the first to fifth embodiments, the second surface PL2 of the valve body 2 was formed on a surface located at the same position as the first surface PL1, or on a surface located further inward than the first surface PL1, in the direction normal to the first surface PL1. In other words, the second surface PL2 was formed on a surface that did not protrude from the first surface PL1 in the direction normal to the first surface PL1.

[0115] However, the second surface PL2 is not limited to being formed in a shape that does not protrude from the first surface PL1 over its entire area. It is sufficient that the adjacent portion adjacent to at least a part of the edge of the first surface PL1 does not protrude from the first surface PL1 in the direction normal to the first surface PL1 (i.e., it is in the same position as the first surface PL1 or is further inward of the valve body 2 than the first surface PL1). The second surface PL2 is an example of a surface that includes an adjacent portion.

[0116] This adjacent portion is formed by machining the pre-machined first surface portion PL11 of the molded product MA, MA3, MA4, and MA5 to form the first surface portion PL1, and is based on a pre-machined adjacent portion (adjacent portion) that is adjacent to at least a part of the edge of the pre-machined first surface portion PL11. The pre-machined adjacent portion should have a shape that prevents the tool from interfering with the pre-machined first surface portion PL11 when machining it, thereby suppressing the generation of burrs. In other words, the pre-machined adjacent portion that is adjacent to at least a part of the edge of the pre-machined first surface portion PL11 should be formed in a shape that is lower than the pre-machined first surface portion PL11, and this pre-machined adjacent portion should prevent the cutting tool from interfering with the part of the pre-machined left side LTL1 that is not the pre-machined first surface portion PL11. Because the pre-processing adjacent portion of the pre-processing first surface portion PL11 has the shape described above, when the pre-processing first surface portion PL11 is subjected to cutting to form the first surface portion PL1, the adjacent portion adjacent to at least a part of the edge of the first surface portion PL1 will have a shape that does not protrude from the first surface portion PL1 in the direction normal to the first surface portion PL1.

[0117] To put it another way, the pre-machined first surface portion PL11 has a shape that protrudes more than the pre-machined adjacent portion adjacent to at least a part of the edge of the pre-machined first surface portion PL11 on the pre-machined left side LTL1 of the molded product, and the pre-machined adjacent portion should function as a clearance portion that avoids the cutting tool. By clearance, I mean that the cutting tool does not interfere with it.

[0118] The second face portion PL2 may have a shape such that, for example, the portion opposite to the first face portion PL1 protrudes more than the first face portion PL1 in the direction normal to the first face portion PL1.

[0119] Alternatively, in the first embodiment, the second surface PL2 is formed on a surface located inward of the first surface PL1 in the direction normal to the first surface PL1. However, for example, a part of the second surface PL2 may be located at the same position as the first surface PL1 in the direction normal to the first surface PL1. For example, a part of the second surface PL2 has a shape that follows the return channel 23 and is formed as a curved surface that protrudes outward. The top of this second surface PL2 may be located at the same position as the first surface PL1 in the direction normal to the first surface PL1.

[0120] Furthermore, in the first to fifth embodiments, the first surface portion PL11 before processing was subjected to milling as an example of cutting. The cutting process is not limited to milling, and may be a cutting process other than milling. Also, in the first to fifth embodiments, the first surface portion PL1 was formed by cutting the molded products MA, MA3, MA4, and MA5, but the first surface portion PL1 may be formed by grinding instead of or in addition to cutting. [Explanation of symbols]

[0121] 1: Expansion valve unit 2: Valve body 3: Valve body 4: Biasing device 5: Actuator rod 6: Actuator rod vibration damping spring 8: Power Element 20: Alveolar seat 21: First channel 22: Second channel 23: Return channel 26: Ring section 27: Actuator rod insertion hole 41: Coil spring 100: Solenoid valve unit 140: Attractor 150: Plunger 160: Pilot valve body 170: Main valve body 180: Coil Unit 181: Electromagnetic coil 182: Housing ESV: Expansion valve with solenoid valve MA, MA3, MA4, MA5: Molded products

Claims

1. In a valve device having a valve body, One side surface of the valve body comprises a base surface portion which is a flat surface to which an object to be fixed can be attached, formed by a predetermined cutting or grinding process, and an adjacent portion which is adjacent to at least a part of the edge of the base surface portion. Of the aforementioned side surfaces, only the base surface portion is subjected to the predetermined cutting or grinding process, while the adjacent portion is not subjected to the predetermined cutting or grinding process and has a shape that does not protrude from the base surface portion in the direction normal to the base surface portion. A valve device characterized by the following features.

2. Tool marks are formed on the base surface, and lines formed by extrusion molding are formed on the adjacent portion. The valve device according to feature 1.

3. The aforementioned side surface has another planar portion formed on the same plane or substantially the same plane as the base surface portion, and the adjacent portion is a recess located between the base surface portion and the other planar portion. The valve device according to feature 1.

4. The valve device includes a solenoid valve as the object to be fixed. A valve device according to any one of claims 1 to 3, characterized by the features described herein.

5. A valve body having a valve chamber, an orifice formed on the upper surface of the valve chamber, a supply-side passage communicating with the valve chamber and the outside and supplying refrigerant to the valve chamber, a discharge-side passage communicating with the orifice and the outside and discharging the refrigerant from the orifice to the outside, and a return passage for carrying the refrigerant discharged from the discharge-side passage, A valve body arranged in the valve chamber, A power element provided on the upper surface of the valve body, which generates a driving force to drive the valve body, An operating rod that transmits the driving force of the power element to the valve body, An object to be fixed is attached to one side of the valve body, Equipped with, The supply-side flow path extends from the front surface of the valve body to the valve chamber. The discharge side passage extends from the back surface of the valve body to the orifice. The return channel extends from the front to the back, The discharge channel is located above the supply channel, The return channel is located above the discharge channel, The side surface includes a recess formed along the return channel, and a base surface portion which is a flat surface to which the object to be fixed can be attached, formed by performing a predetermined cutting or grinding process from the lower end of the side surface to the recess. Of the aforementioned side surfaces, only the base surface portion is subjected to the predetermined cutting or grinding process. An expansion valve characterized by the following features.

6. A first step of forming an intermediate product of a valve body from a material, wherein one side of the intermediate product has a base surface portion before processing and an adjacent portion adjacent to at least a part of the edge of the base surface portion before processing, and the base surface portion before processing has a shape that protrudes from the adjacent portion, The process includes a second step of performing cutting or grinding on the aforementioned pre-processing base surface to form a base surface that is a flat surface capable of fixing the object to be fixed, In the second step, the base surface is formed by cutting or grinding only the pre-processed base surface on one side of the intermediate workpiece so that the adjacent portion does not protrude from the base surface in the direction normal to the base surface. A method for manufacturing a valve device characterized by the following:

7. In the second step, the base surface is formed by milling the base surface before processing. The method for manufacturing a valve device according to claim 6.

8. In the first step described above, another planar portion is formed that faces the pre-processing base surface portion with the adjacent portion in between, and is on the same plane or substantially the same plane as the base surface portion. The method for manufacturing a valve device according to claim 6.

9. In the first step, the pre-processing base surface, the adjacent portion, and the other planar portion are formed by extrusion molding. The method for manufacturing a valve device according to feature 8.

10. A valve body having a valve chamber, an orifice formed on the upper surface of the valve chamber, a supply-side passage communicating with the valve chamber and the outside and supplying refrigerant to the valve chamber, a discharge-side passage communicating with the orifice and the outside and discharging the refrigerant from the orifice to the outside, and a return passage for carrying the refrigerant discharged from the discharge-side passage, A valve body arranged in the valve chamber, A power element provided on the upper surface of the valve body, which generates a driving force to drive the valve body, An operating rod that transmits the driving force of the power element to the valve body, An object to be fixed is attached to one side of the valve body, Equipped with, The supply-side flow path extends from the front surface of the valve body to the valve chamber. The discharge side passage extends from the back surface of the valve body to the orifice. The return channel extends from the front to the back, The discharge channel is located above the supply channel, A method for manufacturing an expansion valve, wherein the return passage is located above the discharge passage, A first step of forming an intermediate product of the valve body from a material, wherein one side of the intermediate product has a base surface portion before processing and an adjacent portion adjacent to at least a part of the edge of the base surface portion before processing, and the base surface portion before processing has a shape that protrudes from the adjacent portion, The process includes a second step of performing cutting or grinding on the pre-processing base surface to form a base surface that is a flat surface on which the object to be fixed can be fixed, In the second step, the base surface is formed by cutting or grinding only the pre-processed base surface on one side of the intermediate workpiece so that the adjacent portion does not protrude from the base surface in the direction normal to the base surface. A method for manufacturing an expansion valve, characterized by the following:

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