Solenoid valve and expansion valve with solenoid valve

Abstract

Provided are a solenoid valve and an expansion valve with the solenoid valve that can ensure smooth flow of fluid when the valve is opened. The solenoid valve comprises: a solenoid valve chamber; a valve body having an inlet-side flow path communicating with the solenoid valve chamber, a recess, and an outlet-side flow path formed on a bottom surface of the recess; a valve hole connecting the outlet-side flow path and the solenoid valve chamber; a first valve part that is attached to the recess of the valve body by any one of press-fitting, gluing, screw-fixing, or snap-fitting; and a second valve part that is seated against the first valve part to cover the valve hole, and that is separated from the first valve part to open the valve hole. Materials of the first valve part and the second valve part have different Young's modulus values. A surface of the second valve part on the first valve part side is composed of a single member. When an end of the first valve part is projected toward the second valve part along an axial direction of the valve hole, a projected image thereof does not overlap with the valve body at least between the inlet-side flow path and the outlet-side flow path in the solenoid valve chamber.

Description

Solenoid valve and expansion valve with solenoid valve

[0001] The present invention relates to a solenoid valve and an expansion valve with a solenoid valve.

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

[0003] Patent Document 1 discloses a configuration in which an expansion valve has a valve port provided in a communication passage connecting a primary passage into which high-pressure refrigerant flows and an expansion valve chamber, and a solenoid valve is attached to open or close the valve port.

[0004] Japanese Patent Application Publication No. 08-210733

[0005] According to the configuration of Patent Document 1, a valve portion fixed to the tip of a plunger abuts against or separates from a valve port that protrudes in a cylindrical shape from the valve body, thereby opening or closing the valve port. The disc-shaped valve portion is inserted into a recess at the tip of the plunger, and a crimped portion that protrudes from the plunger toward the valve port is bent toward the valve portion to secure the valve portion to the plunger (see Figure 4 of Patent Document 1). Therefore, for example, when the valve portion is slightly separated from the valve port, refrigerant flows into the expansion valve chamber through the gap between the valve port and the valve portion. However, the crimped portion may create flow resistance and generate turbulence, potentially reducing the flow rate of the refrigerant passing through the valve port.

[0006] The present invention has been made in view of the above-mentioned problems, and has an object to provide a solenoid valve and an expansion valve with a solenoid valve that can ensure a smooth flow of fluid when the valve is open.

[0007] The solenoid valve of the present invention comprises: a valve body including a solenoid valve chamber, an inlet-side flow path communicating with the solenoid valve chamber, a recess, and an outlet-side flow path formed in the bottom surface of the recess; a first valve portion including a valve hole connecting the outlet-side flow path and the solenoid valve chamber and attached to the recess of the valve body by press-fitting, bonding, screw fixing, or snap-fitting; and a second valve portion that seats against the first valve portion to block the valve hole and opens the valve hole by separating from the first valve portion, wherein the first valve portion and the second valve portion are made of materials with different Young's moduli; a surface of the second valve portion facing the first valve portion is made of a single member; and when an end of the first valve portion is projected toward the second valve portion along the axial direction of the valve hole at least between the inlet-side flow path and the outlet-side flow path in the solenoid valve chamber, the projected image does not overlap with the valve body. a solenoid valve body including a solenoid valve chamber, an inlet-side flow path connecting a flow path downstream of the valve chamber to the solenoid valve chamber, a recess, and an outlet-side flow path formed in the bottom surface of the recess; a first valve portion including a valve hole connecting the outlet-side flow path to the solenoid valve chamber and attached to the recess of the valve body by press-fitting, bonding, screw fixing, or snap-fitting; and a second valve portion that seats against the first valve portion to block the valve hole and opens the valve hole by separating from the first valve portion, wherein the first valve portion and the second valve portion are made of materials with different Young's moduli; a surface of the second valve portion facing the first valve portion is made of a single member; and wherein, at least between the inlet-side flow path and the outlet-side flow path in the solenoid valve chamber, when an end of the first valve portion is projected toward the second valve portion along the axial direction of the valve hole, the projected image does not overlap with the valve body.

[0008] The present invention can provide a solenoid valve and an expansion valve with a solenoid valve that can ensure a smooth flow of fluid when the valve is open.

[0009] FIG. 1 is a schematic cross-sectional view showing a solenoid valve-equipped expansion valve according to a first embodiment. FIG. 2 is a longitudinal cross-sectional view of the solenoid valve-equipped expansion valve, taken at a cross section shifted in phase by 90 degrees around the axis L from FIG. 1. FIG. 3 is a bottom view of the configuration of FIG. 2, cut along line A-A. FIG. 4 is a cross-sectional view showing an enlarged view of the vicinity of a solenoid valve chamber. FIG. 5 is a schematic cross-sectional view similar to FIG. 2, showing a solenoid valve-equipped expansion valve according to a second embodiment. FIG. 6 is an enlarged cross-sectional view similar to FIG. 4, of the solenoid valve-equipped expansion valve according to the second embodiment. FIG. 7 is a schematic cross-sectional view similar to FIG. 2, showing a solenoid valve-equipped expansion valve according to a third embodiment. FIG. 8 is an enlarged cross-sectional view similar to FIG. 4, of the solenoid valve-equipped expansion valve according to the third embodiment. FIG. 9 is a schematic cross-sectional view similar to FIG. 2, showing a solenoid valve-equipped expansion valve according to a fourth embodiment. FIG. 10 is an enlarged cross-sectional view similar to FIG. 4, of the solenoid valve-equipped expansion valve according to the fourth embodiment. FIG. 11 is a schematic cross-sectional view similar to FIG. 2, showing a solenoid valve-equipped expansion valve according to a fifth embodiment. FIG. 12 is an enlarged cross-sectional view similar to FIG. 4 of a solenoid-valve-equipped expansion valve according to a fifth embodiment. FIG. 13 is a schematic cross-sectional view similar to FIG. 2 showing a solenoid-valve-equipped expansion valve according to a sixth embodiment. FIG. 14 is an enlarged cross-sectional view similar to FIG. 4 of a solenoid-valve-equipped expansion valve according to the sixth embodiment. FIG. 15 is a schematic cross-sectional view similar to FIG. 2 showing a solenoid-valve-equipped expansion valve according to a seventh embodiment. FIG. 16 is an enlarged cross-sectional view similar to FIG. 4 of a solenoid-valve-equipped expansion valve according to the seventh embodiment. FIG. 17 is a schematic cross-sectional view similar to FIG. 2 showing a solenoid-valve-equipped expansion valve according to an eighth embodiment. FIG. 18 is an enlarged cross-sectional view similar to FIG. 4 of a solenoid-valve-equipped expansion valve according to the eighth embodiment. FIG. 19 is an enlarged cross-sectional view similar to FIG. 1 of a solenoid-valve-equipped expansion valve according to a ninth embodiment. FIG. 20 is a side view of the configuration shown in FIG. 19, cut along line B-B except for the solenoid valve and its vicinity, and cut along line C-C to show the solenoid valve and its vicinity. FIG. 21 is a bottom view of the configuration shown in FIG. 19, cut along line D-D.

[0010] First Embodiment Hereinafter, an embodiment of a solenoid valve-equipped expansion valve, which is one type of valve device of the present invention, will be described with reference to the drawings. The solenoid valve-equipped expansion valve ESV comprises an expansion valve unit (also called an expansion valve) 1 and a solenoid valve unit (also called a solenoid valve) 100, but they share a valve body 2.

[0011] (Structure of Expansion Valve Unit) The structure of the expansion valve unit 1 of this embodiment will be described below with reference to Fig. 1. Fig. 1 is a schematic cross-sectional view showing a solenoid valve-equipped expansion valve ESV of this embodiment. First, the structure of the expansion valve unit 1 in the solenoid valve-equipped expansion valve ESV will be described.

[0012] The expansion valve unit 1 includes a valve body 2 having an expansion 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 designated as L.

[0013] In addition to the expansion valve chamber VS, the valve body 2 includes a first flow path 21, a second flow path 22, and a return flow path 23. The first flow path 21 is a supply-side flow path, and refrigerant (also referred to as fluid) is supplied to the expansion valve chamber VS via the supply-side flow path. The second flow path 22 is a discharge-side flow path, and the fluid in the expansion valve chamber VS is discharged to the outside of the expansion valve via the actuating rod insertion hole 27, the intermediate passage 22a, and the discharge-side flow path. The first flow path 21 and the expansion valve chamber VS are connected via an inlet-side flow path 112 and an outlet-side flow path 113 (FIG. 3), which will be described later.

[0014] The spherical valve element 3 is disposed in the expansion valve chamber VS. When the valve element 3 is seated on the annular valve seat 20 of the valve body 2, the expansion valve chamber VS and the second flow path 22 are not in communication with each other. On the other hand, when the valve element 3 is separated from the valve seat 20, the expansion valve chamber VS and the second flow path 22 are in communication with each other.

[0015] The lower end of the actuating rod 5, which is inserted with a gap through the actuating rod insertion hole 27, is in contact with the upper surface of the valve element 3. The actuating rod 5 can press the valve element 3 in the valve opening direction against the biasing force of the biasing device 4. When the actuating rod 5 moves toward the valve element, the valve element 3 moves away from the valve seat 20, and the expansion valve unit 1 enters the open state.

[0016] The actuating rod 5 extends along the axis L from the valve body 3 to the power element 8 through an actuating rod insertion hole 27, a central hole 28, an annular portion 26, a return flow path 23, and a communication path 2b, which are coaxially formed in the valve body 2. The inner diameter of the annular portion 26 is larger than the inner diameter of the central hole 28, which slidably holds the actuating rod 5. An actuating rod vibration-damping spring 6, which has a vibration-damping function for the actuating rod 5, is arranged in the annular portion 26.

[0017] The operating rod vibration-damping spring 6 is described in detail in, for example, Japanese Patent Application Laid-Open No. 2018-25332, so description thereof will be omitted here.

[0018] Next, we will explain the power element 8. The power element 8 is attached to a recess 2a provided at the top of the valve body 2. The recess 2a communicates with a return flow path 23 through which the refrigerant from the evaporator passes via a communication path 2b.

[0019] The power element 8 has a plug 81 , an upper cover member 82 , a diaphragm 83 , a stopper member 84 , and a receiving member 86 .

[0020] A hole 82 a is formed at the top of the upper cover member 82 and can be sealed with a plug 81 .

[0021] The diaphragm 83 is made of a thin plate material on which a plurality of concentric circular concave and convex shapes are formed.

[0022] The stopper member 84 has a disk portion and a cylindrical portion coaxially connected to the lower surface of the disk portion, and a fitting hole 84c is formed in the center of the lower end of the cylindrical portion.

[0023] The receiving member 86 has a flange portion having an outer diameter approximately the same as the outer diameter of the upper cover member 82, and a hollow cylindrical portion connected to the lower end of the flange portion, and a male thread 86c is formed on the outer periphery of the hollow cylindrical portion.

[0024] When assembling the power element 8, first, the outer peripheries of the upper cover member 82, the diaphragm 83, and the flange portion of the receiving member 86 are overlapped, and then the outer peripheries are circumferentially welded together using, for example, TIG welding, laser welding, plasma welding, etc.

[0025] Next, working gas is injected into the space surrounded by the upper cover member 82 and the diaphragm 83 (referred to as the pressure actuated chamber PA) through a hole 82a formed in the upper cover member 82, and then the hole 82a is sealed with a plug 81, and the plug 81 is fixed to the upper cover member 82 using projection welding or the like.

[0026] At this time, the diaphragm 83 is pressurized by the working gas sealed in the pressure actuated chamber PA in a manner that causes it to bulge toward the receiving member 86, and is supported by abutting against the upper surface of the stopper member 84 disposed in the lower space LS surrounded by the diaphragm 83 and the receiving member 86. Note that, because the disk 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.

[0027] When assembling the power element 8 to the valve body 2, with the upper end of the actuating rod 5 fitted into the fitting hole 84c of the stopper member 84, the actuating rod 5 is inserted into the valve body 2 while passing through the actuating rod vibration-proof spring 6 assembled to the valve body 2. Furthermore, the male thread 86c of the receiving member 86 is threaded into the female thread of the recess 2a of the valve body 2, and the power element 8 is fixed to the valve body 2 by screwing it in. The gap between the valve body 2 and the power element 8 is sealed by a packing PK. In this state, the lower space LS of the power element 8 communicates with the return flow path 23, i.e., they have the same internal pressure.

[0028] Next, the biasing device 4 will be described. In Figure 1, the biasing device 4 has a coil spring 41 made of a circular wire wound in a spiral shape, a valve element support 42 attached to the upper end of the coil spring 41 to support the valve element 3, and a spring bearing member 43 attached to the valve body 2 while supporting the lower end of the coil spring 41. The spring bearing member 43 seals the expansion valve chamber VS of the valve body 2 and has the function of supporting the end of the coil spring 41 that biases the valve element 3 toward the valve seat 20.

[0029] The spherical valve element 3 is welded to the upper surface of the valve element support 42, and the two are integrated together.

[0030] (Structure of Solenoid Valve Unit) Next, the structure of the solenoid valve unit 100 of this embodiment will be described with reference to Figures 2 to 4. The solenoid valve unit 100 of this embodiment is a so-called pilot-type solenoid valve unit.

[0031] Fig. 2 is a longitudinal cross-sectional view of the solenoid valve-equipped expansion valve ESV in a cross section shifted in phase by 90 degrees around the axis L from Fig. 1. Fig. 3 is a bottom view of the configuration of Fig. 1 cut along line A-A. The axis of the solenoid valve unit 100 is O. Fig. 4 is an enlarged cross-sectional view showing the vicinity of the solenoid valve chamber VE.

[0032] 2 and 3, the solenoid valve unit 100 includes a valve body 2, an attractor 140, a plunger 150, a pilot valve element 160, a main valve element 170, and a coil unit 180. The attractor 140 and the coil unit 180 constitute a drive unit. The axis of the solenoid valve unit 100 is designated by O.

[0033] Within the valve body 2, there are formed an inlet-side flow path 112 (Figure 3) connected to the first flow path 21, an outlet-side flow path 113 connected to the expansion valve chamber VS, and a cylindrical solenoid valve chamber VE communicating with the inlet-side flow path 112 and the outlet-side flow path 113.

[0034] In FIG. 4 , an annular recess 113a is formed at the end of the outlet-side flow path 113 on the solenoid valve chamber VE side. In other words, the outlet-side flow path 113 is formed on the bottom surface of the recess 113a (similar to the embodiments described below). A circular pipe member 114 made of PTFE or rubber is attached to the recess 113a by press-fitting or adhesive. The interior of the circular pipe member 114 forms a valve hole connecting the solenoid valve chamber VE and the outlet-side flow path 113. The outer diameter of the end of the circular pipe member 114 on the recess 113a side is equal to the inner diameter of the recess 113a, and the overall length of the circular pipe member 114 is longer than the depth of the recess 113a. Therefore, when attached to the recess 113, the tip of the circular pipe member 114 protrudes into the solenoid valve chamber VE. The inner diameter of the circular pipe member 114 is uniform and equal to the inner diameter of the outlet-side flow path 113. The inner diameter of the tip side of the circular pipe member 114 is preferably smaller than the outer diameter of the end portion on the recess 113a side of the circular pipe member 114. The tip shape of the circular pipe member 114 is preferably such that the outer diameter gradually decreases toward the tip and the inner diameter gradually increases toward the tip. Preferably, the cross section of the outer wall tip of the circular pipe member 114 in the axial O direction has an arc shape. The circular pipe member 114 serves as a first valve portion having a tip that abuts in line contact with the flat end surface of the main valve body 170.

[0035] The mounting surface 2c, which forms the side surface of the valve body 2, is a flat surface perpendicular to the axis O. A circular recess 2d opens into the mounting surface 2c coaxially with the axis O. The circular recess 2d is a stepped opening, and a female thread 2e is formed on the mounting surface side, and a solenoid valve chamber VE is formed at the back of the circular recess 2d.

[0036] A portion of the suction element 140 is installed within the circular recess 2d. The suction element 140 is composed of a disk-shaped base 141 and a shaft 142 that is smaller in diameter than the base 141 and that are coaxially connected to each other. The base 141 has a circular opening 141a formed in the center of the end portion on the valve body side. A guide hole 141b is formed between the base 141 and the shaft 142, penetrating in the direction of the axis O, so as to communicate with the center of the opening 141a.

[0037] A disk-shaped main valve element 170 is disposed within the opening 141a and is slidable along the axis O. A pilot valve hole 170a is formed through the center of the main valve element 170, which is made of brass, for example, in the direction of the axis O. An annular recess 170b is formed at the end of the pilot valve hole 170a on the guide hole 141b side. A PTFE or rubber annular member 171 is attached to the recess 170b by press-fitting or adhesive. That is, the annular member 171 is not fixed to the main valve element 170 by caulking. In other words, when the end of the annular member 171 facing the pilot valve element 160 along the axis O is projected toward the pilot valve element 160, the projected image does not overlap with the main valve element 170. The outer diameter of the annular member 171 is equal to the inner diameter of the recess 170b, and the thickness of the annular member 171 is approximately equal to the depth of the recess 170b. The inner diameter of the annular member 171 is approximately equal to the inner diameter of the pilot valve hole 170a.

[0038] The surface of the main valve element 170 facing the circular pipe member 114 is composed of a single member (as in the embodiments described below). The end surface of the main valve element (second valve portion) 170 facing the valve body is flat and can be seated on the tip of the circular pipe member 114. A pressure equalizing passage (not shown) penetrating along the axis O is formed adjacent to the pilot valve hole 170a, but the formation of a pressure equalizing passage is not essential. The main valve element 170 is urged toward the shaft portion 142 against the edge of the base portion 141 of the attractor 140 by a partial conical spring 173.

[0039] By threading the male thread 141c formed on the outer periphery of the base 141 into the female thread 2e formed on the inner periphery of the circular recess 2d, the suction element 140 is fixed to the valve body 2 while its outer periphery abuts against the inner circumferential step of the circular recess 2d, thereby forming a solenoid valve chamber VE inside the circular recess 2d. At this time, an O-ring OR is disposed between the base 141 and the circular recess 2d to prevent refrigerant from leaking from the solenoid valve chamber VE through the gap between them.

[0040] 2, with the base 141 attached to the circular recess 2d, the shaft 142 protrudes in a direction perpendicular to the attachment surface 2c. Near the end of the shaft 142, the end of a thin-walled, closed-top cylindrical can member 144 is fitted onto the outer periphery of the shaft 142 and joined coaxially by welding or brazing. A plunger 150 is disposed inside the can member 144.

[0041] Plunger 150, which has a hollow cylindrical shape, is arranged to be slidable in the direction of axis O relative to can member 144. Cylindrical pilot valve element 160, which is made of brass, for example, comprises a head 161, a body 162 having a smaller diameter than head 161, and a tapered portion 163 (FIG. 3) formed at the end of body 162, which are connected together.

[0042] Pilot valve element 160 is held relative to plunger 150 with head 161 locked onto a reduced diameter portion on the inner periphery of the end of plunger 150. In this state, body 162 of pilot valve element 160 protrudes from plunger 150 toward the valve body and is inserted into guide hole 141 b of shaft 142 of suction element 140, and a portion of tapered portion 163 protrudes into opening 141 a and faces the center of annular member 171 attached to main valve element 170.

[0043] A spring 151 is disposed between the top of the can member 144 and the head 161 of the pilot valve body 160, and urges the pilot valve body 160 toward the valve body 2. In addition, an intermediate spring 152 is disposed between the shaft portion 142 and the inner end of the plunger 150, and urges the plunger 150 in a direction away from the valve body 2.

[0044] The coil unit 180 has a hollow cylindrical electromagnetic coil 181 and a housing 182 that holds the electromagnetic coil 181 .

[0045] When the solenoid valve unit 100 is assembled, the electromagnetic coil 181 is located radially outside the plunger 150 with the can member 144 sandwiched therebetween.

[0046] (Operation of Expansion Valve Unit) With reference to Figure 1, an example of operation when a solenoid-equipped expansion valve ESV is incorporated into a refrigeration cycle will be described. Refrigerant pressurized by a compressor in a refrigeration cycle (not shown) is liquefied in a condenser and sent to the expansion valve unit 1. Refrigerant adiabatically expanded by the expansion valve unit 1 is sent to the evaporator of the refrigeration cycle and exchanges heat with air flowing around the evaporator. Refrigerant returning from the evaporator passes through the expansion valve unit 1 (more specifically, the return flow path 23) and is returned to the compressor side. By passing through the evaporator, the fluid pressure in the second flow path 22 becomes greater than the fluid pressure in the return flow path 23.

[0047] High-pressure refrigerant is supplied from the condenser to the expansion valve unit 1. More specifically, the high-pressure refrigerant from the condenser is supplied to the first flow path 21. Here, it is assumed that the solenoid valve unit 100 is in an open state. In this case, the refrigerant supplied to the first flow path 21 reaches the expansion valve chamber VS via the inlet-side flow path 112, the solenoid valve chamber VE, and the outlet-side flow path 113.

[0048] When the valve disc 3 is seated on the valve seat 20, the first flow path 21 on the upstream side of the expansion valve chamber VS and the second flow path 22 on the downstream side of the expansion valve chamber VS are not in communication with each other. On the other hand, when the valve disc 3 is separated from the valve seat 20, the refrigerant supplied to the expansion valve chamber VS is sent to the evaporator through the actuating rod insertion hole 27 and the second flow path 22. The expansion valve unit 1 is switched between the closed state and the open state by the actuating rod 5 connected to the power element 8.

[0049] 1, the power element 8 is provided with a pressure actuated chamber PA and a lower space LS separated by a diaphragm 83. Therefore, when the working gas in the pressure actuated chamber PA is liquefied, the working rod 5 moves toward the diaphragm, and when the liquefied working gas is vaporized, the working rod 5 moves toward the valve body. In this way, the expansion valve unit 1 is switched between the open state and the closed state.

[0050] Furthermore, the lower space LS of the power element 8 is connected to the return flow path 23. Therefore, the phase (gas phase, liquid phase, etc.) of the working gas in the pressure actuated chamber PA changes depending on the temperature and pressure of the refrigerant flowing through the return flow path 23, thereby driving the actuating rod 5. In other words, in the expansion valve unit 1 shown in Fig. 1, the amount of refrigerant supplied from the expansion valve unit 1 to the evaporator is automatically adjusted depending on the temperature and pressure of the refrigerant returning from the evaporator to the expansion valve unit 1.

[0051] On the other hand, when the solenoid valve unit 100 is in a closed state, the communication between the solenoid valve chamber VE and the outlet side flow path 113 is blocked, so that the refrigerant supplied to the first flow path 21 is not supplied from the first flow path 21 to the expansion valve chamber VS, and its flow is blocked.

[0052] (Opening and Closing Operation of Solenoid Valve Unit) Next, a description will be given of the opening and closing operation of the solenoid valve unit 100. Here, the space on the plunger side of the opening 141a partitioned by the main valve body 170 is referred to as a pilot space PS (FIG. 4).

[0053] 2 and 3 , when power is supplied to the electromagnetic coil 181 from a power source (not shown), the magnetic field generated by the electromagnetic coil 181 creates a magnetic path that passes through the plunger 150, the attractor 140, and the housing 182, generating a magnetic force that presses 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 element 160 moves in the same direction, and the tapered portion 163 enters the annular member 171 and abuts against its inner peripheral end. This blocks the pilot valve hole 170a of the main valve element 170, further pressing the main valve element 170 toward the valve body 2.

[0054] The pressed main valve element 170 moves toward the valve body 2 against the biasing force of the spring 173, and its end face seats on the end of the circular tubular member 114. In this closed valve state, the pressure in the pilot space PS, which communicates with the inlet-side flow path 112 via the pressure equalizing passage (or the gap between the opening 141a and the main valve element 170), is greater than the internal pressure of the circular tubular member 114, which communicates with the outlet-side flow path 113. Therefore, the main valve element 170 remains seated on the end of the circular tubular member 114 (blocking the valve hole) against the biasing force of the intermediate spring 152, i.e., the solenoid valve unit 100 is in a closed valve state, and the flow of refrigerant from the inlet-side flow path 112 to the outlet-side flow path 113 is blocked.

[0055] In contrast, when the power supply to the electromagnetic coil 181 from the power source (not shown) 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, so that the pilot valve body 160 moves away from the valve body 2 and the tapered portion 163 moves away from the annular member 171, thereby opening the pilot valve hole 170a of the main valve body 170.

[0056] As a result, the pilot space PS is connected to the interior of the circular pipe member 114 via the pilot valve hole 170a (the valve hole is opened), and fluid flows from the pilot space PS to the outlet-side flow path 113. This causes the internal pressure of the circular pipe member 114 to rise, and the pressures in the spaces in the axial direction O are balanced across the main valve element 170. At this time, the main valve element 170 is separated from the valve body 2 by the biasing force of the spring 173, entering an open state, and a gap is created between the main valve element 170 and the end of the circular pipe member 114, allowing refrigerant to flow from the inlet-side flow path 112 to the outlet-side flow path 113 through this gap.

[0057] According to this embodiment, when the end of the circular pipe member (first valve portion) 114 facing the main valve element (second valve portion) 170 along the axis O is projected onto the main valve element 170 side at least between the inlet-side flow path 112 and the outlet-side flow path 113 in the solenoid valve chamber VE, the projected image does not overlap with the valve body 2. Therefore, when the solenoid valve unit 100 is open, the refrigerant flowing from the inlet-side flow path 112 through the solenoid valve chamber VE to the outlet-side flow path 113 is not obstructed, ensuring a smooth flow. Furthermore, when the solenoid valve unit 100 is operating, the circular pipe member 114 is only biased by a force from the main valve element 170 toward the valve body 2, and is not biased to come out of the recess 113 a.

[0058] Second Embodiment Fig. 5 is a schematic cross-sectional view similar to Fig. 2 showing a solenoid valve-equipped expansion valve ESV according to a second embodiment. Fig. 6 is an enlarged cross-sectional view similar to Fig. 4 of the solenoid valve-equipped expansion valve ESV according to the second embodiment. In this embodiment, only the configurations of the main valve element 170A of the solenoid valve unit 100A and the circular pipe member 114A are different from those of the first embodiment. The other configurations and operations are the same as those of the first embodiment, so duplicated explanations will be omitted.

[0059] In Figure 6, a main valve element 170A is slidably disposed along an axis O within an opening 141a of a base 141 of a suction element 140. The main valve element 170A, made of brass, for example, comprises a large-diameter cylindrical portion 175A and a small-diameter cylindrical portion 176A, which are coaxially connected to each other. A tubular portion 177A having the same outer diameter as the small-diameter cylindrical portion 176A is formed at the end of the small-diameter cylindrical portion 176A facing the valve body 2. In a cross section of the tubular portion 177A taken along the axis O, the cross section of the tip of the outer wall has an arc shape. The tip of the tubular portion 177A forms a second valve portion that abuts in line contact with the flat end surface of the circular pipe member 114A.

[0060] A pilot valve hole 170Aa is formed through the center of the main valve body 170A in the axial direction O, and an annular recess 170Ab is formed at the end of the pilot valve hole 170Aa. A PTFE or rubber annular member 171 is attached to the recess 170Ab by press-fitting or adhesive. The outer diameter of the annular member 171 is equal to the inner diameter of the recess 170Ab, and the thickness of the annular member 171 is approximately equal to the depth of the recess 170Ab. The inner diameter of the annular member 171 is also approximately equal to the inner diameter of the pilot valve hole 170Aa.

[0061] An annular recess 113a is formed at the end of the outlet-side flow path 113, which communicates with the solenoid valve chamber VE, on the solenoid valve chamber VE side. A circular pipe member 114A made of PTFE or rubber is attached to the recess 113a by press-fitting or adhesive, and is held in the recess 113a around its entire circumference, thereby suppressing deformation. The inner diameter of the circular pipe member 114A is equal to the inner diameter of the outlet-side flow path 113. The outer diameter of the circular pipe member 114A is equal to the inner diameter of the recess 113a, and the overall length of the circular pipe member 114A is equal to the depth of the recess 113a. Therefore, when attached to the recess 113a, the tip of the circular pipe member 114A does not protrude into the solenoid valve chamber VE but is generally flush with the peripheral surface of the recess 113a. The exposed flat end surface of the circular pipe member 114A serves as a first valve portion, and the valve is closed when the tip of the tubular portion 177A abuts against it in a line contact.

[0062] According to this embodiment, when the end of the circular pipe member (first valve portion) 114A facing the main valve element (second valve portion) 170A along the axis O in the solenoid valve chamber VE at least between the inlet-side flow path 112 and the outlet-side flow path 113 is projected onto the main valve element 170A, the projected image does not overlap with the valve body 2. In other words, because the circular pipe member 114A is not fixed to the valve body 2 by crimping, when the solenoid valve unit 100A is opened, the refrigerant flowing from the inlet-side flow path 112 through the solenoid valve chamber VE to the outlet-side flow path 113 is not obstructed, ensuring a smooth flow. Furthermore, by reducing the diameter of the end of the main valve element 170A on the circular pipe member 114A side to create a gap with the opening 141a, the distance of the flow path can be shortened, reducing pressure loss and suppressing a decrease in flow rate.

[0063] (Third embodiment) Fig. 7 is a schematic cross-sectional view similar to Fig. 2 showing a solenoid valve-equipped expansion valve ESV according to a third embodiment, but only the lower side of the expansion valve unit is shown in cross section. Fig. 8 is an enlarged cross-sectional view similar to Fig. 4 of the solenoid valve-equipped expansion valve ESV according to the third embodiment. In this embodiment, only the configuration of the main valve element 170B of the solenoid valve unit 100B is different from that of the second embodiment, and the other configurations and operations are the same as those of the second embodiment, so duplicated explanations will be omitted.

[0064] 8, a main valve element 170B is disposed within an opening 141a of a base 141 of a suction element 140 so as to be slidable along an axis O. The main valve element 170B, made of brass, for example, comprises a large-diameter cylindrical portion 175B and a small-diameter cylindrical portion 176B that are coaxially connected together. A tubular portion 177B having the same outer diameter is formed at the end of the small-diameter cylindrical portion 176B facing the valve body 2. In a cross section of the tubular portion 177B taken along the axis O, the cross section of the tip of the outer wall has an arc shape. The tip of the tubular portion 177B forms a second valve portion that abuts in line contact with the flat end surface of the circular pipe member 114A.

[0065] Furthermore, in this embodiment, a guide tube portion 178B is formed coaxially with the tubular portion 177B and protrudes from the end of the small diameter cylindrical portion 176B toward the valve body 2.

[0066] A pilot valve hole 170Ba is formed through the center of the main valve body 170B in the axial direction O, extending to the end of the guide tube portion 178B. An annular recess 170Bb is formed at the end of the pilot valve hole 170Ba opposite the guide tube portion 178B. A PTFE or rubber annular member 171 is attached to the recess 170Bb by press-fitting or adhesive. The outer diameter of the annular member 171 is equal to the inner diameter of the recess 170Bb, and the thickness of the annular member 171 is approximately equal to the depth of the recess 170Bb. The inner diameter of the annular member 171 is also approximately equal to the inner diameter of the pilot valve hole 170Ba.

[0067] In this embodiment as well, at least between the inlet-side flow path 112 and the outlet-side flow path 113 in the solenoid valve chamber VE, when the end of the circular pipe member (first valve portion) 114A facing the main valve element (second valve portion) 170B along the direction of the axis O is projected onto the main valve element 170B side, the projected image does not overlap with the valve body 2. In other words, because the circular pipe member 114A is not fixed to the valve body 2 by crimping, when the solenoid valve unit 100B is opened, the refrigerant flowing from the inlet-side flow path 112 through the solenoid valve chamber VE to the outlet-side flow path 113 is not obstructed, ensuring a smooth flow.

[0068] Furthermore, according to this embodiment, when the solenoid valve unit is closed, the guide tube portion 178B enters the interior of the circular pipe member 114A with a gap therebetween. Therefore, immediately after the solenoid valve unit starts to open, the guide tube portion 178B is located inside the circular pipe member 114A, and the flow of refrigerant entering the outer side of the inner circumference of the circular pipe member 114A from the solenoid valve chamber VE and the flow of refrigerant from the pilot space PS through the pilot valve hole 170Ba toward the inner side of the circular pipe member 114A are mixed together, thereby ensuring a smoother flow of refrigerant.

[0069] (Fourth embodiment) Fig. 9 is a schematic cross-sectional view similar to Fig. 2 showing a solenoid valve-equipped expansion valve ESV according to a fourth embodiment, but only the lower side of the expansion valve unit is shown in cross section. Fig. 10 is an enlarged cross-sectional view similar to Fig. 4 of the solenoid valve-equipped expansion valve ESV according to the fourth embodiment. In this embodiment, only the configuration of the main valve element 170C of the solenoid valve unit 100C is different from that of the second embodiment, and the other configurations and operations are the same as those of the second embodiment, so duplicated explanations will be omitted.

[0070] 10, a main valve element 170C is disposed within an opening 141a of a base 141 of a suction element 140 so as to be slidable along an axis O. The main valve element 170C, which is made of brass, for example, comprises a large-diameter cylindrical portion 175C and a small-diameter cylindrical portion 176C that are coaxially connected together. In this embodiment, the end face of the small-diameter cylindrical portion 176C facing the valve body 2 is flat. The end face of the small-diameter cylindrical portion 176C forms a second valve portion that abuts in surface contact with the flat end face of the circular pipe member 114A.

[0071] A pilot valve hole 170Ca is formed through the center of the main valve body 170C in the axial direction O and opens at the end of the small-diameter cylindrical portion 176C. An annular recess 170Cb is formed at the end of the pilot valve hole 170Ca on the large-diameter cylindrical portion 175C side. A PTFE or rubber annular member 171 is attached to the recess 170Cb by press-fitting or adhesive. The outer diameter of the annular member 171 is equal to the inner diameter of the recess 170Cb, and the thickness of the annular member 171 is approximately equal to the depth of the recess 170Cb. The inner diameter of the annular member 171 is approximately equal to the inner diameter of the pilot valve hole 170Ca.

[0072] In this embodiment as well, at least between the inlet-side flow path 112 and the outlet-side flow path 113 in the solenoid valve chamber VE, when the end of the circular pipe member (first valve portion) 114A facing the main valve element (second valve portion) 170C is projected along the axis O toward the main valve element 170C, the projected image does not overlap with the valve body 2. In other words, because the circular pipe member 114A is not fixed to the valve body 2 by crimping, when the solenoid valve unit 100C is opened, the refrigerant flowing from the inlet-side flow path 112 through the solenoid valve chamber VE to the outlet-side flow path 113 is not obstructed, ensuring a smooth flow.

[0073] Fifth Embodiment Fig. 11 is a schematic cross-sectional view similar to Fig. 2 showing a solenoid valve-equipped expansion valve ESV according to a fifth embodiment, but only the lower side of the expansion valve unit is shown in cross section. Fig. 12 is an enlarged cross-sectional view similar to Fig. 4 of the solenoid valve-equipped expansion valve ESV according to the fifth embodiment. In the solenoid valve-equipped expansion valve ESV of this embodiment, the structure of the expansion valve unit 1 is similar to that of the above embodiments, but the solenoid valve unit 200 differs from the above embodiments in that it is a solenoid valve unit of a solenoid valve type. The axis of the solenoid valve unit 200 is designated as O.

[0074] In FIG. 12 , an annular recess 113a is formed at the end of the outlet-side flow path 113 communicating with the solenoid valve chamber VE on the solenoid valve chamber VE side. A circular pipe member 114B made of PTFE or rubber is attached to the recess 113a by press-fitting or adhesive and protrudes into the solenoid valve chamber VE. The circular pipe member 114B comprises a rear end portion 114Ba on the recess 113a side, a middle portion 114Bb having a smaller outer diameter than the rear end portion 114Ba, and a front end portion 114Bc having a smaller outer diameter than the middle portion 114Bb. Preferably, the cross section of the outer wall tip of the circular pipe member 114B in the axial O direction has an arc-shaped cross section. The tip of the circular pipe member 114B forms a first valve portion that abuts in line contact with the flat end surface of the plunger 235.

[0075] In Figure 11, the solenoid valve unit 200 includes a base 220, a coil 232 for energizing and exciting, a yoke 233, an attractor 240 having a pipe 241 arranged on the inner periphery of the yoke 233 and extending in the direction of axis O, a plunger (second valve portion) 235 arranged on the inner periphery of the pipe 241 so as to be able to slide freely in the direction of axis O, and a housing 238 arranged to cover these.

[0076] 12, the base 220 is formed by connecting a circular flange 221 and a circular pipe 222, and the end of the pipe 241 is fixed to the inner periphery of the base 220 by press-fitting, brazing, or the like. The base 220 is fixed to the valve body 2 by threading a male thread 222a formed on the outer periphery of the circular pipe 222 into a female thread 2e formed on the inner periphery of a circular recess 2d of the valve body 2, thereby forming a solenoid valve chamber VE in the circular recess 2d. At this time, a packing PK is disposed between the flange 221, which contacts the mounting surface 2c of the valve body 2, and the valve body 2, to prevent refrigerant from leaking from the solenoid valve chamber VE through a gap therebetween.

[0077] 11 , an internal thread 242 is formed on the end face of the suction element 240 opposite to the pipe 241. The suction element 240 and the housing 238 are joined by threading a mounting bolt 237 into the internal thread 242 with the housing 238 interposed therebetween. The housing 238 is fixed to the flange 221 of the base 220 via a spacer 239.

[0078] The cylindrical plunger 235 is made of metal (e.g., brass) and has an enlarged diameter portion 235a and a reduced diameter portion 235b connected together. The plunger 235 is biased in the valve closing direction (toward the circular pipe member 114B) by a compression coil spring 236 that is compressed between the plunger 235 and the attractor 240.

[0079] In the solenoid valve unit 200 configured as described above, when power is not supplied to the solenoid section (drive section) consisting of the coil 232 and the attractor 240, the force of the compression coil spring 236 causes the plunger 235 to approach the circular pipe member 114B, and the plunger 235 maintains its end face seated on the tip end 114Bc of the circular pipe member 114B. In other words, the solenoid valve unit 200 is in a closed state, and the flow of refrigerant from the solenoid valve chamber VE connected to the inlet side flow path (not shown) to the outlet side flow path 113 is blocked.

[0080] On the other hand, when power is supplied to the solenoid portion, the force of the compression coil spring 236 urges the plunger 235 in a direction away from the circular pipe member 114B, and the end face of the plunger 235 moves away from the tip end 114Bc of the circular pipe member 114B, thereby opening the valve hole of the circular pipe member 114B. As a result, the solenoid valve unit 200 enters an open state, and the solenoid valve chamber VE communicates with the inside of the circular pipe member 114, allowing the fluid to flow to the outlet-side flow path 113.

[0081] In this embodiment, at least between the inlet-side flow path and the outlet-side flow path 113 in the solenoid valve chamber VE, when the end of the circular pipe member (first valve portion) 114B facing the plunger (second valve portion) 235 along the axis O is projected onto the plunger 235 side, the projected image does not overlap with the valve main body 2. Therefore, when the solenoid valve unit 200 is opened, the refrigerant flowing from the inlet-side flow path through the solenoid valve chamber VE to the outlet-side flow path 113 is not obstructed, ensuring a smooth flow.

[0082] (Sixth embodiment) Fig. 13 is a schematic cross-sectional view similar to Fig. 2 showing a solenoid valve-equipped expansion valve ESV according to a sixth embodiment, but only the lower side of the expansion valve unit is shown in cross section. Fig. 14 is an enlarged cross-sectional view similar to Fig. 4 of the solenoid valve-equipped expansion valve ESV according to the sixth embodiment. In this embodiment, only the configurations of the plunger 235A of the solenoid valve unit 200A and the circular pipe member 114C are different from those of the fifth embodiment. The other configurations and operations are the same as those of the fifth embodiment, so duplicated explanations will be omitted.

[0083] The cylindrical plunger 235A comprises an enlarged diameter portion 235Aa and a reduced diameter portion 235Ab connected together. A tubular portion 235Ad, whose outer diameter is smaller than that of the reduced diameter portion 235Ab, is formed at the end of the plunger 235A facing the valve body 2. In a cross section of the tubular portion 235Ad taken along the axis O, the cross section of the tip of the outer wall is arc-shaped. The tip of the tubular portion 235Ad forms a second valve portion that abuts in line contact with the flat end surface of the circular pipe member 114C.

[0084] An annular recess 113a is formed at the end of the outlet-side flow path 113, which communicates with the solenoid valve chamber VE, on the solenoid valve chamber VE side. A circular pipe member 114C made of PTFE or rubber is attached to the recess 113a by press-fitting or adhesive. The interior of the circular pipe member 114C forms a valve hole connecting the solenoid valve chamber VE and the outlet-side flow path 113. The outer diameter of the circular pipe member 114C is equal to the inner diameter of the recess 113a, and the overall length of the circular pipe member 114C is equal to the depth of the recess 113a. Therefore, when attached to the recess 113a, the tip of the circular pipe member 114C does not protrude into the solenoid valve chamber VE but is substantially flush with the surrounding surface of the recess 113a. The tip surface of the circular pipe member 114C forms a first valve portion.

[0085] According to this embodiment, at least between the inlet-side flow path (not shown) and the outlet-side flow path 113 in the solenoid valve chamber VE, when the end of the circular pipe member (first valve portion) 114C facing the plunger (second valve portion) 235A is projected along the axis O toward the plunger 235A, the projected image does not overlap with the valve body 2. In other words, because the circular pipe member 114C is not fixed to the valve body 2 by crimping, when the solenoid valve unit 200A is opened, the refrigerant flowing from the inlet-side flow path through the solenoid valve chamber VE to the outlet-side flow path 113 is not obstructed, ensuring a smooth flow.

[0086] (Seventh embodiment) Fig. 15 is a schematic cross-sectional view similar to Fig. 2 showing a solenoid valve-equipped expansion valve ESV according to a seventh embodiment, but only the lower side of the expansion valve unit is shown in cross section. Fig. 16 is an enlarged cross-sectional view similar to Fig. 4 of the solenoid valve-equipped expansion valve ESV according to the seventh embodiment. In this embodiment, only the configuration of the plunger 235B of the solenoid valve unit 200B is different from that of the fifth embodiment, and the other configurations and operations are the same as those of the sixth embodiment, so duplicated explanations will be omitted.

[0087] The cylindrical plunger 235B comprises an enlarged diameter portion 235Ba and a reduced diameter portion 235Bb connected together. The end of the plunger 235B facing the valve body 2 is provided with a tubular portion 235Bd having a smaller outer diameter than the reduced diameter portion 235Bb, and a guide columnar portion 235Be having a longer axial length than the tubular portion 235Bd. In a cross section of the tubular portion 235Bd taken along the axis O, the cross section of the tip of the outer wall is arc-shaped. The tip of the tubular portion 235Bd forms a second valve portion that abuts in line contact with the flat end surface of the circular pipe member 114C.

[0088] In the present embodiment as well, when the end of the circular pipe member (first valve portion) 114C facing the plunger (second valve portion) 235B in the solenoid valve chamber VE along the axis O direction is projected onto the plunger 235B side, at least between the inlet-side flow path and the outlet-side flow path 113, the projected image does not overlap with the valve body 2. In other words, because the circular pipe member 114C is not fixed to the valve body 2 by crimping, when the solenoid valve unit 200B is opened, the refrigerant flowing from the inlet-side flow path through the solenoid valve chamber VE to the outlet-side flow path 113 is not obstructed, ensuring a smooth flow.

[0089] Furthermore, according to this embodiment, when the solenoid valve unit is closed, the guide columnar portion 235Be enters the interior of the circular pipe member 114C with a gap therebetween. Therefore, immediately after the solenoid valve unit starts to open, the guide columnar portion 235Be is coaxially positioned inside the circular pipe member 114C, and the refrigerant flows from the solenoid valve chamber VE toward the outlet-side flow path 113 while being guided by the outer periphery of the guide columnar portion 235Be, ensuring a smoother flow of the refrigerant.

[0090] Eighth Embodiment Fig. 17 is a schematic cross-sectional view similar to Fig. 2 showing a solenoid valve-equipped expansion valve ESV according to an eighth embodiment, but only the lower side of the expansion valve unit is shown in cross section. Fig. 18 is an enlarged cross-sectional view similar to Fig. 4 of the solenoid valve-equipped expansion valve ESV according to the eighth embodiment. In this embodiment, only the configuration of the plunger 235C of the solenoid valve unit 200C is different from that of the fifth embodiment, and the other configurations and operations are the same as those of the fifth embodiment, so duplicated explanations will be omitted.

[0091] The cylindrical plunger 235C has an enlarged diameter portion 235Ca and a reduced diameter portion 235Cb connected together. A columnar portion 235Cd having a smaller outer diameter than the reduced diameter portion 235Cb is formed at the end of the plunger 235C facing the valve body 2. The tip of the columnar portion 235Cd forms a second valve portion that abuts in surface contact with the flat end surface of the circular pipe member 114C.

[0092] In the present embodiment as well, when the end of the circular pipe member (first valve portion) 114C facing the plunger (second valve portion) 235C in the solenoid valve chamber VE along the axis O direction is projected onto the plunger 235C side, at least between the inlet-side flow path and the outlet-side flow path 113, the projected image does not overlap with the valve main body 2. In other words, because the circular pipe member 114C is not fixed to the valve main body 2 by crimping, when the solenoid valve unit 200C is opened, the refrigerant flowing from the inlet-side flow path through the solenoid valve chamber VE to the outlet-side flow path 113 is not obstructed, ensuring a smooth flow.

[0093] The present invention is not limited to the above-described embodiments, and it goes without saying that the present invention also includes design changes that do not deviate from the spirit of the present invention.

[0094] For example, while the first valve portion is formed from PTFE or rubber and the second valve portion is formed from metal, materials with different Young's moduli can be used. Examples of materials with different Young's moduli for the first and second valve portions include those in which the first valve portion is formed from PTFE or rubber and the second valve portion is formed from metal, as well as those in which the first valve portion is formed from resin and the second valve portion is formed from metal. Here, resin includes PTFE, rubber, and other resins. Alternatively, the first valve portion may be formed with a convex portion on its outer periphery, and a groove may be formed on the inner periphery of the recess in the valve body, with the convex portion engaging with the groove in a snap-fit ​​manner for attachment.

[0095] In the above-described embodiment, it is also possible to form a male thread on the outer peripheral surface of the circular pipe member 114 and a female thread in the recess 113a, and to fasten the circular pipe member 114 to the valve body 2 by screwing these threads together. Even when fastened by a screw in this way, the projected image of the end of the circular pipe member 114 does not overlap with the valve body 2.

[0096] Furthermore, when the circular pipe member 114 is fixed to the valve body 2 using a crimped portion, it is sufficient that this crimped portion (part of the valve body 2) is not positioned in the flow path of the refrigerant that flows from the inlet side flow path 112 through the solenoid valve chamber EV to the outlet side flow path 113. In other words, such a crimped portion does not overlap with the projected image of the end of the circular pipe member 114.

[0097] Ninth Embodiment Fig. 19 is an enlarged cross-sectional view similar to Fig. 1 of a solenoid valve-equipped expansion valve according to a ninth embodiment. Fig. 20 is a side view of the configuration of Fig. 19 , cut along line B-B except for the solenoid valve and its vicinity, and cut along line C-C to show the solenoid valve and its vicinity, but shows the expansion valve in an open state. Fig. 21 is a bottom view of the configuration of Fig. 19 , cut along line D-D. This embodiment differs from the first embodiment mainly in that inlet-side flow paths 112Da and 112Db leading to the solenoid valve chamber VE of the solenoid valve unit 100 are formed downstream of the valve chamber VC. The remaining configuration (including the configuration of the drive section of the solenoid valve unit 100) is the same as that of the first embodiment, and therefore a repeated description will be omitted.

[0098] The valve body 2D of the expansion valve unit 1D has an actuating rod insertion passage 27D that is a passage downstream of the valve chamber VC and connects to the central bore 28D, and also has multiple (e.g., a pair of upper and lower) inlet-side passages 112Da, 112Db that connect the actuating rod insertion passage 27D to a circular recess 2Dd on the side of the valve body 2D. A solenoid valve chamber VE is formed by fixing the solenoid valve unit 100 to the circular recess 2Dd, and the inlet-side passages 112Da, 112Db communicate with the solenoid valve chamber VE.

[0099] An O-ring OR is disposed in place of the actuating rod vibration-proof spring in the annular portion 26. The O-ring OR is held in the annular portion 26 by a retainer 26a attached to the actuating rod 5, and by sealing the gap between the inner periphery of the annular portion 26 and the outer periphery of the actuating rod 5, it prevents the refrigerant from flowing out of the central hole 28D into the return flow path 23.

[0100] The biasing device 4D of this embodiment also has a valve disc vibration-damping spring 44 sandwiched between the upper end of the coil spring 41 held by the spring receiving member 43 and the valve disc support 42. The valve disc vibration-damping spring 44 exerts a vibration-damping function for the valve disc 3 by bringing multiple legs that protrude radially outward into contact with the inner periphery of the valve chamber VC.

[0101] 21 , the circular pipe member 114 is made of PTFE or rubber and is fixed by press-fitting, bonding, screwing, snap-fitting, or the like into an annular recess 113Da formed in the bottom surface of the circular recess 2Dd, with its tip protruding toward the solenoid valve chamber VE. Furthermore, the bottom surface of the recess 113Da is connected to the intermediate passage 22a of the valve body 2D by an outlet-side flow path 113D. The interior of the circular pipe member 114 forms a valve hole connecting the solenoid valve chamber VE and the outlet-side flow path 113D. The circular pipe member 114 forms the first valve portion, whose tip abuts in line contact with the flat end surface of the metal main valve element 170, which is the second valve portion of the solenoid valve unit 100. The circular pipe member 114 and the main valve element 170 are made of materials with different Young's moduli.

[0102] At least between the inlet side flow paths 112Da, 112Db and the outlet side flow path 113D in the solenoid valve chamber VE, when the end of the circular pipe member 114 is projected along the axial direction of the circular pipe member 114 toward the main valve body 170, the projected image does not overlap with the valve body 2D.

[0103] When power is supplied to the electromagnetic coil 181 of the solenoid valve unit 100 from a power source (not shown), the plunger 150 is pressed, causing the pilot valve body 160 to move toward the main valve body 170, and the tapered portion at the tip of the pilot valve body 160 blocks the pilot valve hole of the main valve body 170 and further presses the main valve body 170 toward the valve body 2.

[0104] The pressed main valve element 170 moves toward the valve body 2 against the biasing force of the spring 173 (see FIG. 4), and its end face seats on the end of the circular pipe member 114, thereby closing the solenoid valve unit 100. Therefore, when the actuation rod 5 separates the valve element 3 from the valve seat 20, connecting the valve chamber VC to the actuation rod insertion passage 27D, even if refrigerant flows into the solenoid valve chamber VE via the inlet-side passages 112Da and 112Db, the flow of refrigerant from the solenoid valve chamber VE to the outlet-side passage 113D is blocked, thereby enabling forced valve closure.

[0105] In contrast, when the power supply to the electromagnetic coil 181 from a power source (not shown) is interrupted, the pilot valve hole of the main valve element 170 is opened. As a result, the main valve element 170 moves away from the valve body 2 due to the biasing force of the spring 173, entering an open valve state, and a gap is created between the main valve element 170 and the end of the circular pipe member 114. Refrigerant flows from the solenoid valve chamber VE to the outlet-side flow path 113D through this gap. In this embodiment, some of the above-described embodiments can be used.

[0106] This specification includes the following disclosure of the invention: (First Aspect) A solenoid valve comprising: a valve body including a solenoid valve chamber, an inlet-side flow path communicating with the solenoid valve chamber, a recess, and an outlet-side flow path formed in a bottom surface of the recess; a first valve portion including a valve hole connecting the outlet-side flow path and the solenoid valve chamber and attached to the recess of the valve body by press-fitting, bonding, screw fixing, or snap-fitting; and a second valve portion that blocks the valve hole by seating against the first valve portion and opens the valve hole by separating from the first valve portion, wherein the first valve portion and the second valve portion are made of materials with different Young's moduli, and a surface of the second valve portion facing the first valve portion is made of a single member, and wherein, at least between the inlet-side flow path and the outlet-side flow path in the solenoid valve chamber, when an end of the first valve portion is projected toward the second valve portion along the axial direction of the valve hole, the projected image does not overlap with the valve body.

[0107] (Second Mode) The solenoid valve of the first mode, characterized in that the first valve portion is a circular tubular member attached by press-fitting or bonding to a recess in the valve body, and protrudes into the solenoid valve chamber.

[0108] (Third Mode) The solenoid valve according to the second mode, wherein the second valve portion has an end face that is in line contact with the end of the circular pipe member.

[0109] (Fourth mode) The solenoid valve of the first mode, characterized in that the first valve portion is a circular tubular member attached by press-fitting or bonding to a recess in the valve body, and does not protrude into the solenoid valve chamber.

[0110] (Fifth Mode) The solenoid valve according to the fourth mode, wherein the second valve portion has a tubular portion that is in line contact with the end surface of the circular pipe member.

[0111] (Sixth Mode) The solenoid valve according to the fourth mode, wherein the second valve portion is in surface contact with the end surface of the circular pipe member.

[0112] (Seventh form) The solenoid valve of the sixth form, characterized in that the second valve portion is a main valve body having a guide tube portion arranged inside the tubular portion and a pilot valve hole passing through the guide tube portion in the axial direction, and when the second valve portion is seated on the first valve portion, at least a part of the guide tube portion advances inside the circular pipe member.

[0113] (Eighth Mode) The solenoid valve of the fifth mode, wherein the second valve portion has a guide column portion inside the tubular portion, and the guide column portion enters the valve hole with a gap when the second valve portion is seated on the first valve portion.

[0114] (Ninth Mode) The solenoid valve according to any one of the first to eighth modes, wherein the first valve portion is made of PTFE or rubber, and the second valve portion is made of metal.

[0115] (Tenth Mode) The solenoid valve according to any one of the first to ninth modes, further comprising a drive unit for moving the second valve portion toward or away from the first valve portion.

[0116] (Eleventh mode) A solenoid valve comprising: a valve body including a solenoid valve chamber, an inlet-side flow path connecting a flow path downstream of the valve chamber to the solenoid valve chamber, a recess, and an outlet-side flow path formed in a bottom surface of the recess; a first valve portion including a valve hole connecting the outlet-side flow path to the solenoid valve chamber and attached to the recess of the valve body by press-fitting, bonding, screw fixing, or snap-fitting; and a second valve portion that seats against the first valve portion to block the valve hole and opens the valve hole by separating from the first valve portion, wherein the first valve portion and the second valve portion are made of materials with different Young's moduli; a surface of the second valve portion facing the first valve portion is made of a single member; and when an end of the first valve portion is projected toward the second valve portion along the axial direction of the valve hole at least between the inlet-side flow path and the outlet-side flow path in the solenoid valve chamber, the projected image does not overlap with the valve body.

[0117] (12th mode) The solenoid valve of the 11th mode, wherein the first valve portion is a circular pipe member attached to a recess of the valve body and protrudes into the solenoid valve chamber.

[0118] (13th mode) The solenoid valve according to the 11th mode, wherein the second valve portion has an end face that is in line contact with the end of the circular pipe member.

[0119] (14th Mode) The solenoid valve of the 11th mode, wherein the first valve portion is made of PTFE or rubber, and the second valve portion is made of metal.

[0120] (15th mode) The solenoid valve of the 11th mode, further comprising a drive unit for moving the second valve unit toward or away from the first valve unit.

[0121] (16th form) An expansion valve with a solenoid valve comprising an expansion valve and the solenoid valve of any of the 1st to 15th forms, wherein the valve body has a valve chamber with which the outlet side flow path is connected and which has a valve seat, and a flow path downstream of the valve chamber, and the expansion valve comprises: the valve body; a valve element disposed in the valve chamber; a biasing device that biases the valve element toward the valve seat; an actuating rod that moves the valve element in a direction away from the valve seat; and a power element that drives the actuating rod.

[0122] DESCRIPTION OF SYMBOLS 1, 1D: Expansion valve unit 2, 2D: Valve body 3: Valve element 4, 4D: Biasing device 5: Actuating rod 6: Actuating rod vibration-proof spring 8: Power element 20: Valve seat 21: First flow path 22: Second flow path 23: Return flow path 26: Annular portion 27: Actuating rod insertion hole 41: Coil spring 100, 100A, 100B, 100C, 200, 200A, 200B, 200C Solenoid valve unit 140, 240 Suction element 150, 235, 235A, 235B, 235C Plunger 160 Pilot valve element 170, 170A, 170B, 170C Main valve element 180 Coil unit 232 Coil ESV Expansion valve with solenoid valve VS Expansion valve chamber VE Solenoid valve chamber PS Pilot valve chamber

Claims

1. a valve body including a solenoid valve chamber, an inlet side flow passage communicating with the solenoid valve chamber, a recess, and an outlet side flow passage formed on a bottom surface of the recess; a first valve portion including a valve hole connecting the outlet side flow path and the solenoid valve chamber, the first valve portion being attached to the recess of the valve body by any one of press-fitting, bonding, screw fixing, and snap-fitting; a second valve portion that is seated against the first valve portion to block the valve hole and that is separated from the first valve portion to open the valve hole, the first valve portion and the second valve portion are made of materials having different Young's moduli; a surface of the second valve portion facing the first valve portion is formed of a single member; when an end of the first valve portion is projected toward the second valve portion along an axial direction of the valve hole at least between the inlet side flow path and the outlet side flow path in the solenoid valve chamber, the projected image does not overlap with the valve body, the first valve portion is a circular tube member attached to a recess of the valve body and does not protrude into the solenoid valve chamber; the second valve portion has a tubular portion that is in line contact with an end surface of the circular tubular member, the second valve portion is a main valve body including a guide tube portion disposed inside the tubular portion and a pilot valve hole passing through the guide tube portion in the axial direction, When the second valve portion is seated on the first valve portion, at least a portion of the guide tube portion enters the inside of the circular pipe member. A solenoid valve characterized by:

2. The first valve portion is made of PTFE or rubber, and the second valve portion is made of metal.

2. The solenoid valve according to claim 1.

3. a drive unit for moving the second valve unit toward or away from the first valve unit; 2. The solenoid valve according to claim 1.

4. The valve body has a valve chamber having a valve seat and a flow path downstream of the valve chamber, The inlet side flow passage connects the downstream side flow passage and the solenoid valve chamber.

2. The solenoid valve according to claim 1.

5. The valve body has a valve chamber having a valve seat and a flow path downstream of the valve chamber, The outlet side flow path communicates with the valve chamber.

2. The solenoid valve according to claim 1.

6. An expansion valve with a solenoid valve, comprising an expansion valve and the solenoid valve according to any one of claims 1 to 5, The expansion valve is the valve body including a valve chamber and a valve seat; a valve body disposed in the valve chamber; a biasing device that biases the valve body toward the valve seat; an actuation rod that moves the valve body in a direction away from the valve seat; A power element that drives the actuation rod; An expansion valve with a solenoid valve, comprising: