Solenoid valve

Abstract

To provide a constant-open solenoid valve in which a coil can be common to a constant-close valve.SOLUTION: A cartridge-type solenoid valve which can be fitted to a valve mounting hole of a flow passage block, includes: a valve body 12 having a valve chamber 13, an inflow passage 14, and an outflow passage 15; a valve body 18; and an electromagnetic drive device 41. The valve body has: an outer body 21 having a through hole 25 and a body 22 fitted to the valve mounting hole; and an inner body 31 fixed in the through hole. The inner body includes: a trunk part 33 provided at the same height as the body; and a cylinder part 34 below the trunk part. The trunk part has a valve port 16 opening in the valve chamber and having a valve seat 17 at a lower end thereof, and forms a flow passage gap 37 communicating with an outflow hole between the trunk part and the body. The solenoid valve includes: a valve holder 19 supporting the valve body in the cylinder part in a slidable manner; and a transmission mechanism 47 for transmitting a vertical movement of a plunger 43 to the valve holder. The inflow passage communicates with the valve chamber through inside the cylinder part from a lower face of the cylinder part, and the outflow passage includes a communication passage 36 formed at the trunk part so as to communicate the valve port with the flow passage gap.SELECTED DRAWING: Figure 1

Description

Technical Field

[0005]

[0001] The present invention relates to a solenoid valve, and particularly to a normally open type solenoid valve.

Background Art

[0002] Solenoid valves that use electromagnetic actuators to open and close valves have been conventionally used in refrigeration cycle devices equipped with refrigerant circuits such as air conditioners, refrigerators, and freezers.

[0003] Such solenoid valves include a normally closed type (always closed type) that opens only when energized and a normally open type (always open type) that closes only when energized. Also, solenoid valves include a direct acting type that directly moves the valve body by an electromagnetic coil to open and close the valve, and a pilot type that opens and closes a pilot valve by an electromagnetic coil and opens and closes the main valve in response to the opening and closing of this pilot valve. These solenoid valves are properly selected according to the intended use.

[0004] FIG. 9 shows an example of a conventional normally closed type solenoid valve. As shown in this figure, the solenoid valve 91 includes a valve body 92, a valve element 98, and an electromagnetic drive device 41 that drives the valve element 98. The valve body 92 has a valve chamber 93 inside, and an inflow passage 94 for allowing refrigerant to flow into the valve chamber 93 and an outflow passage 95 for allowing refrigerant to flow out from the valve chamber 93. The end of the outflow passage 95 on the valve chamber side is a valve port 96, and a valve seat 97 is formed on the upper surface portion of the valve port 96. The valve element 98 moves forward and backward (up and down) with respect to the valve seat 97 and opens and closes the valve port 96 (outflow passage 95) by contacting and separating from the valve seat 97.

[0005] The electromagnetic drive device 41 includes a plunger 43 slidably mounted within a sleeve 42, a suction element 44 that attracts the plunger 43, a coil (located outside the sleeve 42 but not shown in Figure 9 / see reference numeral 46 in Figure 10) that generates a magnetic force to attract the plunger 43 to the suction element 44, and a valve closing spring (compression coil spring) 99 positioned above the plunger 43 (between the plunger 43 and the suction element 44) to bias the plunger 43 downward (i.e., the valve body 98 in the valve closing direction). The valve body 98 is fixed to the lower end of the plunger 43.

[0006] Furthermore, if we define the direction from the valve seat 97 toward the electromagnetic drive unit 41 as "up" and the direction from the electromagnetic drive unit 41 toward the valve seat 97 as "down", the outflow passage 95 extends downward from the valve port 96 along the central axis of the solenoid valve 91 (valve body 98 and plunger 43, etc.), and then extends in the front-rear direction (perpendicular to the plane of the paper) at the lower part of the valve body 92 and opens to the outside of the valve body 92 (on the outer circumferential surface of the valve body 92). The inflow passage 94 extends upward from the lower surface of the valve body 92 inside the valve body 92, outside the outflow passage 95, and communicates with the valve chamber 93.

[0007] Figure 9 shows the state when the coil is not energized, and the valve body 98 is pressed against the valve seat 97 via the plunger 43 by the valve closing spring 99, closing the valve opening 96 (outlet passage 95). On the other hand, when the coil is energized, the plunger 43 is attracted to the suction element 44 and moves upward, the valve body 98 moves away from the valve seat 97, and the valve opening 96 is opened. This results in an open valve state where the inlet passage 94 and the outlet passage 95 are connected (the symbol F in the figure indicates the flow of refrigerant).

[0008] Furthermore, while the solenoid valve 91 can be used as a direct-acting solenoid valve, it is also possible to configure a pilot-operated solenoid valve by using the solenoid valve 91 as a pilot valve.

[0009] Specifically, as shown in Figures 10 to 12, the pilot-operated solenoid valve is configured such that the solenoid valve 91 is fitted into a valve mounting hole 64 of a flow path block 61a which has a valve mounting hole 64 into which the solenoid valve 91 can be fitted. The flow path block 61a includes a main valve chamber 73, an inlet 62 for introducing refrigerant into the main valve chamber 73, an outlet 63 for releasing refrigerant from the main valve chamber 73, a main valve opening 77 formed between the main valve chamber 73 and the outlet 63, a main valve seat 78 formed on the upper surface of the main valve opening 77, and a main valve body 74 provided in the main valve chamber 73 so as to move back and forth (up and down) relative to the main valve seat 78 to open and close the main valve opening 77.

[0010] In this pilot-operated solenoid valve, the solenoid valve 91 acts as a pilot valve, so the valve chamber 93 is referred to as the "pilot valve chamber" and the valve seat 97 as the "pilot valve seat". The valve mounting hole 64 has an upper hole 65 that is above the valve mounting hole 64 and a lower hole 66 that is below it. The upper hole 65 has a large inner diameter and has a female thread portion 70 on its inner circumferential surface. A male thread portion 23 that screws into the female thread portion 70 is formed on the outer circumferential surface of the valve body 92, and the valve body 92 is fixed to the flow path block 61a by these mutually screwing thread portions (female thread portion 70 and male thread portion 23).

[0011] Furthermore, the lower hole 66 has a small inner diameter, and for this reason, a stepped portion 67 is formed between the upper hole 65 and the lower hole 66. The lower end of the valve body 92 is fitted into the upper part of the lower hole 66. A ring-shaped space 68 (referred to as the "stepped portion space") is formed on the upper surface of the stepped portion 67 (between the stepped portion 67 and the valve body 92), and the outflow passage 95 is in communication with this stepped portion space 68. In addition, a connecting passage 69 is formed in the flow path block 61a so as to connect the stepped portion space 68 and the outflow hole 63, and these outflow passage 95, stepped portion space 68 and connecting passage 69 form a pilot passage 72 that connects the pilot valve chamber 93 and the outflow hole 63.

[0012] Furthermore, the main valve body 74 is provided with a pressure equalization passage 75 that connects the main valve chamber 73 and the pilot valve chamber 93 via the inside of the main valve body 74 and the inlet passage 94. In addition, the main valve body 74 is equipped with a main valve closing spring (compression coil spring) 85 that biases the main valve body 74 in the closing direction (downward).

[0013] To describe the operation of the pilot-operated solenoid valve described above, in the closed state shown in Figure 10 (no current supplied to the coil 46), the pilot passage 72 is closed by the pilot valve body 98 seating on the pilot valve seat 97 due to the valve closing spring 99. As a result, the pressure inside the main valve body 74 (upper side of the main valve body 74), which is in communication with the main valve chamber 73 via the pressure equalizing passage 75, becomes equal to the internal pressure of the main valve chamber 73. On the other hand, the internal pressure of the outlet hole 63 is lower than that of the main valve chamber 73. This pressure difference, along with the biasing force of the main valve closing spring 85, causes the main valve body 74 to seat on the main valve seat 78, maintaining the closed state.

[0014] When current is applied to the coil 46, as shown in Figure 11, the plunger 43 is attracted to the suction element 44, causing it to rise against the biasing force of the valve closing spring 99, and the pilot valve body 98 separates from the pilot valve seat 97, opening the pilot passage 72. As a result, the refrigerant introduced into the interior (upper side) of the main valve body 74 through the pressure equalization passage 75 is released to the outlet hole 63 through the pilot passage 72 (see symbol F), and the pressure on the upper side of the main valve body 74 decreases. Furthermore, since the cross-sectional area of ​​the pilot passage 72 is larger than that of the pressure equalization passage 75, and the amount of refrigerant released from the pilot valve chamber 93 to the outlet hole 63 through the pilot passage 72 is greater than the amount of refrigerant flowing from the main valve chamber 73 to the upper side of the main valve body 74 through the pressure equalization passage 75, the pressure on the upper side of the main valve body 74 becomes lower than the pressure inside the main valve chamber 73, and a differential pressure is generated on the upper and lower surfaces of the main valve body 74, pulling the main valve body 74 upward. Therefore, when this differential pressure exceeds the biasing force of the main valve closing spring 85, as shown in Figure 12, the main valve body 74 is pulled upward and separated from the main valve seat 78, the main valve opening 77 is opened, and the inlet hole 62 and outlet hole 63 are in communication, resulting in an open valve state.

[0015] Furthermore, Patent Document 1 below discloses a normally open type solenoid valve. [Prior art documents] [Patent Documents]

[0016] [Patent Document 1] Japanese Patent Publication No. 2020-060269 (Japanese Patent No. 6815655) [Overview of the Initiative] [Problems that the invention aims to solve]

[0017] Incidentally, solenoid valves generally have a longer overall length (axial length, i.e., length in the direction of valve body movement) in the normally open type than in the normally closed type, which presents the challenge of not being able to use the same coil for both normally closed and normally open types.

[0018] On the other hand, if the coil can be shared between normally closed and normally open types, it will be possible to improve the productivity of solenoid valves and reduce manufacturing costs.

[0019] Therefore, the objective of the present invention is to obtain a normally open type valve structure that can share a coil with a normally closed type solenoid valve. [Means for solving the problem]

[0020] [First Invention] To solve the aforementioned problems and achieve the objective, the solenoid valve according to the first invention of the present application comprises a valve body having a valve chamber, an inlet passage for introducing a fluid (e.g., refrigerant / hereinafter the same) into the valve chamber, an outlet passage for discharging the fluid from the valve chamber, and a valve seat formed in the valve chamber; a valve element that moves back and forth relative to the valve seat; and an electromagnetic drive device for driving the valve element.

[0021] Furthermore, the electromagnetic drive device includes a sleeve that rises upward from the upper surface of the valve body, a plunger housed within the sleeve so as to be slidable in the vertical direction, a suction element fixed to the upper end of the sleeve to attract the plunger, and an opening spring that biases the plunger downward.

[0022] Furthermore, the valve body includes an outer body having a through-hole extending vertically in the central portion and a ring-shaped body portion, and an inner body fixed within the through-hole. The inner body has a fixing head that is inserted and fitted into the upper portion of the through-hole to fix the inner body to the outer body, a body portion disposed below the fixing head and at a height position overlapping with the body portion in the vertical direction, and a cylindrical cylinder portion formed below the body portion.

[0023] The valve chamber is formed at the inner upper end portion of the cylinder portion. The body portion has a valve port that opens toward the valve chamber. Also, a valve seat is formed at the lower end portion of the valve port, and a valve body is disposed within the valve chamber so as to face the valve seat. Further, a flow path gap through which fluid can pass is formed between the outer peripheral surface of the body portion and the inner peripheral surface of the body portion.

[0024] Furthermore, the solenoid valve includes a valve body holder that supports the valve body slidably in the vertical direction within the cylinder portion, and a transmission mechanism that transmits the vertical movement of the plunger to the valve body via the valve body holder and moves the valve body up and down together with the plunger. Note that the valve body holder may be integrated with the valve body (that is, the valve body and the valve body holder may be configured as one member) (the same applies to the second invention described later).

[0025] The inflow path is formed to communicate with the valve chamber from the lower surface of the cylinder portion through the space between the outer peripheral surface of the valve body holder and the inner peripheral surface of the cylinder portion. On the other hand, the outflow path includes a communication path formed in the body portion so as to communicate the valve port and the flow path gap.

[0026] In the present application, the axial direction of the solenoid valve (valve body, valve port, valve seat, electromagnetic drive device) is defined as the "vertical direction", one direction of the vertical direction (the direction from the valve seat to the electromagnetic drive device) is defined as "up", and the other direction of the vertical direction (the direction from the electromagnetic drive device to the valve seat) is defined as "down". Based on the concepts of "up" and "down", terms related to up and down such as "above", "below", "rise", "fall", "upper part", "lower part", "upper side", and "lower side" are used in the present application. Also, the position in the vertical direction is referred to as the "height position". However, since the solenoid valves of the present invention and each of the embodiments described later can be used in various orientations, it is not always the case that "down" is the direction of gravity and "up" is the opposite direction of gravity. In the present application, the above-described first invention and the second invention described later are collectively referred to as the "present invention".

[0027] Also, the solenoid valves according to the above-described first invention and the second invention described later are so-called cartridge-type solenoid valves that are mounted on a flow path block having an inflow hole for allowing fluid to flow in, an outflow hole for allowing fluid to flow out, and a valve mounting hole capable of receiving the solenoid valve. The mounting of the solenoid valve on the flow path block is performed by fitting (for example, screwing) the main body portion of the valve body into the valve mounting hole. In this mounted state, the inflow path of the solenoid valve communicates with the inflow hole of the flow path block, and the flow path gap of the solenoid valve communicates with the outflow hole of the flow path block.

[0028] In the first invention of the present application, the valve body is divided into an outer body having a main body portion that is fitted into the valve mounting hole and承担 the fixing function with respect to the flow path block, and an inner body having a valve chamber and a valve seat (valve port) inside and承担 the opening and closing function of the flow path. The inner body is disposed in a nested manner within the through hole of the outer body, and the main body portion and the valve chamber and valve seat (valve port) are disposed at the same height position (a position overlapping in the vertical direction). Thereby, including the sleeve that houses the plunger, the length of the valve body in the vertical direction can be made the same as that of a normally closed type solenoid valve (see FIGS. 1 and 9), and it becomes possible to use the same coil as that of a normally closed type solenoid valve (that is, to share the coil) (see FIGS. 4 and 10). Note that the coil is provided so as to surround the sleeve.

[0029] Regarding the operation of the solenoid valve according to the first invention described above, when the electromagnetic drive device (coil) is not powered, the plunger is pushed downward by the biasing force of the valve opening spring, causing the valve body to move downward from the valve seat and the valve port to open. Therefore, the fluid that flows into the valve chamber through the inlet hole and inlet passage is discharged outside the valve through the valve port, outlet passage (connecting passage), flow path gap, and outlet hole. In this open valve state, when power is supplied to the electromagnetic drive device (coil), the suction element attracts the plunger, causing the plunger to rise within the sleeve. The rise of the sleeve is transmitted to the valve body via the valve body holder by the transmission mechanism, and the valve body is pulled up. When the valve body seats (contacts) the valve seat, the valve port is closed by the valve body, and the flow path between the inlet hole and the outlet hole is blocked, resulting in a closed valve state.

[0030] Furthermore, in the first invention described above, the transmission mechanism may include an operating rod that extends vertically through the fixed head and body and is interposed between the plunger and the valve body holder to lower the valve body by transmitting the downward movement of the plunger to the valve body holder, and a valve closing spring that biases the valve body holder upward and raises the valve body via the valve body holder when the plunger moves upward.

[0031] In the first invention described above, the valve body is composed of two components (an outer body and an inner body). However, it is possible to achieve the same coil commonality even if the valve body is composed of a single component, and this application discloses such a solenoid valve as the second invention described below.

[0032] [Second Invention] The solenoid valve according to the second invention of the present application, similar to the solenoid valve of the first invention, comprises a valve body having a valve chamber, an inlet passage for introducing fluid into the valve chamber, an outlet passage for introducing fluid out of the valve chamber, and a valve seat formed in the valve chamber; a valve element that moves back and forth relative to the valve seat; and an electromagnetic drive device for driving the valve element. The electromagnetic drive device comprises a sleeve provided so as to rise upward from the upper surface of the valve body; a plunger housed within the sleeve so as to be slidable in the vertical direction; a suction element fixed to the upper end of the sleeve for attracting the plunger; and an opening spring for biasing the plunger downward.

[0033] On the other hand, in the solenoid valve according to the second invention, the valve body has a cylindrical main body and a cylindrical cylinder portion that protrudes downward from the lower surface of the main body. The main body also has a flow channel groove on its outer circumferential surface that extends vertically and allows fluid to pass through. The valve chamber is formed at the upper inner end of the cylinder portion. The main body has a valve port that opens toward the valve chamber. Furthermore, a valve seat is formed at the lower end of the valve port, and a valve body is arranged in the valve chamber so as to face the valve seat.

[0034] Furthermore, the solenoid valve according to the second invention further includes a valve body holder that supports the valve body within the cylinder so that it can slide vertically, and a transmission mechanism that transmits the vertical movement of the plunger to the valve body via the valve body holder, causing the valve body to move vertically together with the plunger. The inlet passage is formed to communicate with the valve chamber from the lower surface of the cylinder, passing between the outer circumferential surface of the valve body holder and the inner circumferential surface of the cylinder. The outlet passage includes a communication passage formed in the main body to connect the valve opening and the flow path groove.

[0035] Furthermore, in the solenoid valve according to the second invention described above, the transmission mechanism may also include, similar to the first invention, an operating rod interposed between the plunger and the valve body holder to transmit the downward movement of the plunger to the valve body holder, thereby lowering the valve body, and a valve closing spring that biases the valve body holder upward and raises the valve body via the valve body holder when the plunger moves upward. In the second invention, the operating rod extends so as to penetrate the main body in the vertical direction.

[0036] Furthermore, in the embodiment in which the transmission mechanism includes an operating rod and a valve closing spring as described above (the same applies to the first invention), it is preferable to set the length of the operating rod to a length such that a gap is formed between the operating rod and the plunger or between the operating rod and the valve body holder when the valve is closed, with the plunger being attracted to and in contact with the suction element and the valve body seated on the valve seat. This is for the following reasons.

[0037] The actuator rod is interposed between the plunger and the valve body holder. However, if the actuator rod is too long (for example, due to variations in length during manufacturing), it may prevent the valve body from seating on the valve seat during the valve closing operation. In contrast, setting the actuator rod to the aforementioned length prevents such a situation from occurring, ensuring that the valve body is securely seated on the valve seat by the closing spring and preventing valve leakage during closing. Of course, the actuator rod must be long enough to push down the valve body via the valve body holder when the plunger has descended to its lowest position, thereby opening the valve port.

[0038] Furthermore, in the above embodiments, the actuator rod is typically fixed to either the plunger or the valve body holder (i.e., the upper end of the actuator rod is fixed to the plunger, or the lower end of the actuator rod is fixed to the valve body holder), but the present invention is not limited to such typical structures. In other words, the present invention does not exclude structures in which the actuator rod is not fixed to either the plunger or the valve body holder, but is merely interposed (in contact), or structures in which the actuator rod is fixed to both the plunger and the valve body holder (these structures are also within the scope of the present invention). [Effects of the Invention]

[0039] According to the present invention, since the normally closed type solenoid valve and coil can be made common, it is possible to improve the productivity of the solenoid valve and reduce manufacturing costs.

[0040] Other objects, features, and advantages of the present invention will be made clear by the following description of embodiments of the present invention based on the drawings. Each figure will appropriately display mutually orthogonal two-dimensional coordinates representing the vertical, horizontal, and front-to-back directions, and the description will be based on these directions. However, as previously stated, the solenoid valves of the present invention and its embodiments can be used in various orientations, and these directions are for convenience of explanation only; the configuration of each part of the present invention is not limited in any way by these directions. Furthermore, in each figure, the same reference numerals indicate the same or corresponding parts. [Brief explanation of the drawing]

[0041] [Figure 1] Figure 1 is a longitudinal cross-sectional view showing a solenoid valve according to a first embodiment of the present invention. [Figure 2] Figure 2 is a longitudinal cross-sectional view showing the solenoid valve according to the first embodiment with a coil attached and mounted on a flow path block (open valve state). [Figure 3] Figure 3 is a longitudinal cross-sectional view showing the solenoid valve according to the first embodiment with a coil attached and mounted on a flow path block (closed valve state). [Figure 4] Figure 4 is a longitudinal cross-sectional view showing the open state of a pilot-operated solenoid valve according to a second embodiment of the present invention. [Figure 5] Figure 5 is a longitudinal cross-sectional view showing the pilot valve of the pilot-operated solenoid valve according to the second embodiment in a closed state. [Figure 6] Figure 6 is a longitudinal cross-sectional view showing the closed state of the pilot-operated solenoid valve according to the second embodiment. [Figure 7] Figure 7 is a longitudinal cross-sectional view showing a solenoid valve according to a third embodiment of the present invention. [Figure 8] Figure 8 is a side view showing the solenoid valve according to the third embodiment. [Figure 9] Figure 9 is a longitudinal cross-sectional view showing an example of a conventional normally closed type solenoid valve. [Figure 10] Figure 10 is a longitudinal cross-sectional view showing a pilot-operated solenoid valve (closed state) in which the conventional solenoid valve is used as a pilot valve. [Figure 11] Figure 11 is a longitudinal cross-sectional view showing the conventional pilot-operated solenoid valve (with the pilot valve open). [Figure 12] Figure 12 is a longitudinal cross-sectional view showing the conventional pilot-operated solenoid valve (in the open state). [Modes for carrying out the invention]

[0042] [First Embodiment] A solenoid valve according to the first embodiment of the present invention will be described with reference to Figures 1 to 3. This first embodiment is a concrete manifestation of the first invention.

[0043] As shown in Figures 1 to 3, the solenoid valve 11 according to the first embodiment of the present invention is a so-called cartridge-type solenoid valve that is incorporated into a refrigeration cycle device, such as a heat pump type heating and cooling system, by being mounted on a flow path block 61 (see Figures 2 and 3) provided in the refrigeration cycle device, and opens and closes the flow path of the refrigerant. It is a normally open type solenoid valve that closes only when energized (when power is supplied to the coil).

[0044] Specifically, the solenoid valve 11 comprises a valve body 12 having a valve chamber 13, an inlet passage 14 for introducing refrigerant into the valve chamber 13, an outlet passage 15 for releasing refrigerant from the valve chamber 13, and a valve port 16 opening into the valve chamber 13; a valve element 18 that opens and closes the valve port 16 by moving back and forth (up and down) relative to a valve seat 17 formed on the lower surface of the valve port 16; a valve element holder 19 that supports the valve element 18; an electromagnetic drive device 41 that drives the valve element 18; and a transmission mechanism 47 that causes the valve element 18 to move up and down in accordance with a plunger 43 (described later).

[0045] The electromagnetic drive device 41 includes a sleeve 42 that rises upward from the upper surface of the valve body 12, a plunger 43 housed within the sleeve 42 so as to be slidable in the vertical direction, a suction element 44 fixed to the upper end of the sleeve 42 so as to attract the plunger 43, and a valve opening spring (compression coil spring) 45 positioned in a compressed state between the suction element 44 and the plunger 43 so as to bias the plunger 43 downward. A coil 46 (see Figures 2 and 3) is installed around the sleeve 42.

[0046] In this embodiment, the valve body 12 consists of an outer body 21 and an inner body 31. The outer body 21 has a fitting portion (corresponding to the "main body portion" of the present invention) 23 that fits into the valve mounting hole 64 of the flow path block 61, a flange portion 24 formed on the upper part of the fitting portion 23 so as to protrude outward from the fitting portion 23, and a through hole 25 that extends vertically along the central axis A of the solenoid valve 11.

[0047] The outer circumferential surface of the fitting portion 23 has a male threaded portion 23 that screws into a female threaded portion 70 formed on the inner circumferential surface of the valve mounting hole 64 of the flow path block 61, so that the valve body 12 can be fixed to the flow path block 61 by screwing the fitting portion 22 into the valve mounting hole 64. When fixing the valve body 12 to the flow path block 61, a sealing material (gasket made of a metal plate) 29 is sandwiched between the lower surface of the flange portion 24 and the upper surface of the flow path block 61 to prevent refrigerant from leaking out to the outside.

[0048] The through hole 25 has a larger diameter enlarged section (referred to as the "upper enlarged section") 26 at its upper end, a smaller diameter reduced section 27 in the middle, and a larger diameter enlarged section (referred to as the "lower enlarged section") 28 at its lower end. The lower end of the sleeve 42 is fitted and fixed into the upper enlarged section 26. The inner body 31 is fixed into the reduced diameter section 27. That is, the inner body 31 has a fixed head 32 at the upper end, a body 33 in the middle, and a cylinder 34 at the lower end, and the inner body 31 is fixed to the outer body 21 by fitting the fixed head 32 into the reduced diameter section 27.

[0049] Furthermore, the lower enlarged diameter portion 28, the fitting portion 22, the male thread portion 23 on the outer circumferential surface of the fitting portion 22, the body portion 33 of the inner body 31, and the horizontal flow channel portion 36 (described later) formed in the body portion 33 are formed or arranged at approximately the same height position (vertical position), or in other words, they overlap in the vertical direction.

[0050] Furthermore, the fixed head 32 of the inner body 31 has a stopper portion 35 that protrudes upward on its upper surface. This stopper portion 35 serves to define the lower limit position of the plunger 43 that moves up and down within the sleeve 42. When the device is not energized (when no power is supplied to the coil 46), the plunger 43, which is biased downward by the valve opening spring 45, is pressed against the stopper portion 35 and cannot move any further downward.

[0051] The body portion 33 of the inner body 31 has a valve opening 16 and a horizontal flow path portion 36 (corresponding to the "communication path" in the present invention) which is part of the outflow passage. The valve opening 16 extends downward from the center of the body portion 33 and opens downward from the lower surface of the center of the body portion 33 toward the interior of the cylinder portion 34. A valve seat 17 is formed on the lower surface of the valve opening 16, upon which the valve body 18 makes contact and separates (contacts and separates). The horizontal flow path portion 36 extends horizontally (in the left-right direction) through the body portion 33, communicates with the valve opening 16 at its center, and both ends open to the outer circumferential surface of the body portion 33 and communicate with the flow path gap 37 (described later).

[0052] The cylinder portion 34 has a cylindrical shape that extends downward from the lower end of the body portion 33, and is hollow inside with an open bottom. Inside the cylinder portion 34, a valve holder 19 supporting a valve body 18 is housed so as to be slidable in the vertical direction, and a valve chamber 13 is formed at the top of the valve holder 19. The valve body 18 is fixed to the center of the upper surface of the valve holder 19 so as to face the valve seat 17. Furthermore, there is an inflow passage 14 between the inner circumferential surface of the cylinder portion 34 and the outer circumferential surface of the valve holder 19, and the refrigerant that flows into the cylinder portion 34 through the opening on the bottom surface of the cylinder portion 34 (through the central hole of the ring-shaped spring retaining plate 50, which will be described later) flows into the valve chamber 13 through the gap between the inner circumferential surface of the cylinder portion 34 and the outer circumferential surface of the valve holder 19.

[0053] Furthermore, the outer diameters of the body portion 33 and cylinder portion 34 of the inner body 31 are made smaller than the inner diameter of the lower enlarged portion 28 of the outer body 21 (through hole 25). As a result, a ring-shaped gap 37 is formed between the outer circumferential surface of the body portion 33 and the outer circumferential surface of the upper end of the cylinder portion 34 and the inner circumferential surface of the fitting portion 23 of the outer body 21 (the inner wall surface of the lower enlarged portion 28). This gap 37 corresponds to the flow path gap referred to in the present invention, and the outflow passage 15 is formed by this gap (flow path gap) 37 and the horizontal flow path portion 36.

[0054] The transmission mechanism 47 includes an operating rod 48 interposed between the plunger 43 and the valve body holder 19, and a valve closing spring (compression coil spring) 49 positioned on the lower surface of the valve body holder 19 so as to bias the valve body 18 upward via the valve body holder 19. The valve closing spring 49 constantly biases the valve body 18 upward and performs the function of causing the valve body holder 19 to follow this movement (rise together with the plunger 43) when the plunger 43 rises. In addition, to support the valve closing spring 49, a ring-shaped spring support plate 50 having a central hole through which refrigerant can pass is fixed to the opening on the lower surface of the cylinder portion 34. The valve closing spring 49 is positioned in a compressed state between the spring support plate 50 and the valve body holder 19.

[0055] In this embodiment, multiple actuator rods (for example, three or four) are provided to stably transmit the downward movement of the plunger 43 to the valve body holder 19, and each actuator rod 48 is arranged radially around the central axis A when viewed from a plane (above or below). The lower end of each actuator rod 48 is fixed to the upper surface of the valve body holder 19, and extends through the body portion 33 and fixed head portion 32 of the inner body 31 to the lower surface of the plunger 43, but the upper end of each actuator rod 48 is not fixed to the plunger 43.

[0056] Furthermore, the length of each actuator rod 48 is set such that when both the plunger 43 and the valve body holder 19 rise to their highest positions, that is, when the plunger 43 is attracted to the suction element 44 and contacts the lower surface of the suction element 44, and the valve body holder 19 is pushed up by the valve closing spring 49 so that the valve body 18 seats (contacts) on the valve seat 17, a small gap (not shown) is formed between the upper end of each actuator rod 48 and the lower surface of the plunger 43. This is to prevent situations in which the actuator rod 48 hinders the seating of the valve body 18 on the valve seat 17 during valve closing operation, and to ensure more reliable valve closing (by pressing the valve body 18 against the valve seat 17 with the valve closing spring 49) and prevent valve leakage. Note that this gap may also be formed on the valve body holder 19 side, in which case the lower end of each actuator rod 48 is not fixed to the valve body holder 19, but the upper end of each actuator rod 48 is fixed to the lower surface of the plunger 43.

[0057] Because the solenoid valve of this embodiment has the structure described above, the height h1 of the valve body 12 (especially the part excluding the flange portion 24) and the overall height h of the solenoid valve including the sleeve 42 can be made the same as that of the normally closed type solenoid valve (see Figure 9), and the coil 46 can be made common with the normally closed type solenoid valve 91.

[0058] On the other hand, the flow path block 61 has a valve mounting hole 64 into which a solenoid valve 11 can be mounted, an inlet hole 62, and an outlet hole 63. The valve mounting hole 64 has an upper hole 65 which is above the valve mounting hole 64 and a lower hole 66 which is below it. The upper hole 65 has a large inner diameter and has the female thread portion 70 on its inner circumferential surface. The lower hole 66 has a small inner diameter, and as a result, a stepped portion 67 is formed between the upper hole 65 and the lower hole 66. A ring-shaped space (this space is referred to as the "stepped portion space") 68 is formed between the upper surface of the stepped portion 67 and the lower surface of the fitting portion 22 (outer body 31), and the flow path gap 37 communicates with the outlet hole 63 through this stepped portion space 68.

[0059] Furthermore, the lower end of the cylinder portion 34 is fitted into the upper part of the pilot hole 66, and an inlet hole 62 is opened at the lower part of the pilot hole 66. The outer circumferential surface of the lower end of the cylinder portion 34 is provided with a sealing material (O-ring) 71. This sealing material 71 is interposed between the inner circumferential surface of the pilot hole 66 and the cylinder portion 34, thereby preventing the refrigerant from leaking out of the inlet hole 62 to the outlet hole 63 via a short circuit.

[0060] The operation of the solenoid valve 11 according to this embodiment is described as follows.

[0061] When the coil 46 is not energized, the plunger 43 is pushed down by the valve opening spring 45, as shown in Figure 2. This pressing force is transmitted to the valve body holder 19 by the actuating rod 48, causing the valve body holder 19 to be pushed down against the biasing force of the valve closing spring 49. As a result, the valve body 18 separates downward from the valve seat 17, and the valve port 16 is opened, resulting in an open valve state. In this open valve state, the refrigerant flowing in from the inlet hole 62 (see symbol F) flows into the valve chamber 13 by passing through the lower part of the lower hole 66 of the valve mounting hole 64, the lower opening of the cylinder part 34 (the central hole of the spring receiving plate 50), and the inlet passage 14 inside the cylinder part 34. The refrigerant that has flowed into the valve chamber 13 flows out from the outlet hole 63 (see symbol F) by passing through the valve port 16, the horizontal flow path section 36, the flow path gap 37, and the stepped space 68 in order.

[0062] When current is applied to the coil 46 in this open state, the plunger 43 is attracted to the suction element 44 and rises, as shown in Figure 3, and comes into contact with the suction element 44. At the same time, the valve body holder 19 is pushed up by the closing spring 49, the valve body 18 sits on the valve seat 17, and the valve opening 16 is closed, resulting in a closed state.

[0063] In this embodiment, a direct-acting solenoid valve is configured to directly open and close the valve using an electromagnetic drive device 41 as described above. However, the solenoid valve 11 in this embodiment can also be used as a pilot valve, and a pilot-operated solenoid valve can be configured as in the second embodiment described below.

[0064] [Second Embodiment] As shown in Figures 4 to 6, the solenoid valve according to the second embodiment of the present invention is a pilot-operated solenoid valve that uses the solenoid valve 11 according to the first embodiment as a pilot valve, and the solenoid valve 11 of the first embodiment is mounted in the valve mounting hole 64 of the flow path block 61a.

[0065] In this embodiment, the same reference numerals are used for components identical or equivalent to those in the first embodiment, and redundant explanations are omitted, with the focus being on the differences (the same applies to the third embodiment described later). In this embodiment, the solenoid valve 11 of the first embodiment is used as a pilot valve, so the valve chamber 13, valve seat 17, and valve body 18 of the solenoid valve 11 of the first embodiment are referred to as the "pilot valve chamber," the valve seat 17, and the valve body 18, respectively.

[0066] The flow path block 61a, like the flow path block 61 in the first embodiment, has a valve mounting hole 64, an inlet hole 62, and an outlet hole 63. The valve mounting hole 64 has an upper hole 65 with a larger inner diameter, a lower hole 66 with a smaller inner diameter, and a stepped portion 67. The lower end of the cylinder portion 34 is fitted into the upper part of the lower hole 66.

[0067] However, in this embodiment, the lower space within the pilot hole 66 is designated as the main valve chamber 73, and the main valve body 74 is provided inside the main valve chamber 73 so as to be able to slide up and down. In addition, a main valve opening 77 is formed on the bottom surface of the pilot hole 66 so as to open upward, and a main valve seat 78, on which the main valve body 74 moves toward and away from, is formed on the upper surface of the main valve opening 77. The inlet hole 62 opens (communicates) with the main valve chamber 73, and the outlet hole 63 opens (communicates) with the main valve chamber 73 via the main valve opening 77. Furthermore, a communication passage 69 is formed in the flow path block 61a to connect the stepped space 68 and the outlet hole 63. The horizontal flow path section 36, the flow path gap 37, the stepped space 68, and the communication passage 69 form a pilot passage 72 that connects the pilot valve chamber 13 and the outlet hole 63.

[0068] Furthermore, the main valve body 74 is provided with a pressure equalization passage 75 that connects the main valve chamber 73 and the pilot valve chamber 13 via the inside of the main valve body 74 and the inside of the cylinder portion 34 (inflow passage 14). The pressure equalization passage 75 has a smaller cross-sectional area than the pilot passage 72 (horizontal flow path portion 36 and communication passage 69). In addition, the main valve body 74 is provided with a main valve closing spring (compression coil spring) 85 inside (between the spring receiving plate 50 and the main valve body 74) that biases the main valve body 74 in the closing direction (downward).

[0069] The operation of the pilot-operated solenoid valve according to this embodiment is described as follows.

[0070] When the coil 46 is not energized, as shown in Figure 4, the plunger 43 is pushed down by the valve opening spring 45, and this pressing force is transmitted to the valve body holder 19 by the operating rod 48, causing the valve body holder 19 to be pushed down against the biasing force of the valve closing spring 45. As a result, the pilot valve body 18 moves downward from the pilot valve seat 17, and the pilot passage 72 is opened. In this state, the refrigerant flowing into the main valve body 74 and the pilot valve chamber 13 through the pressure equalization passage 75 is discharged to the outlet hole 63 through the pilot passage 72 and does not accumulate inside the main valve body 74 (upper side of the main valve body 74). Also, since the amount of refrigerant discharged to the outlet hole 63 through the pilot passage 72 is greater than the amount of refrigerant flowing from the main valve chamber 73 to the upper side of the main valve body 74 through the pressure equalization passage 75, the pressure on the upper side of the main valve body 74 becomes lower than the pressure inside the main valve chamber 73, and a differential pressure that pulls the main valve body 74 upward is generated on the upper and lower surfaces of the main valve body 74. Furthermore, the spring load of the main valve closing spring 85 is set to be smaller than the load caused by this differential pressure. As a result, the main valve body 74 rises against the biasing force of the main valve closing spring 85, separates from the main valve seat 78, and is pressed against the lower surface of the cylinder section 34. Consequently, the valve remains open with the main valve port 77 open, and the refrigerant that flows into the main valve chamber 73 from the inlet hole 62 is discharged to the outside through the main valve port 77 and the outlet hole 63 (see symbol F).

[0071] On the other hand, when the coil 46 is energized in this open state, the plunger 43 is attracted to the suction element 44 and rises against the biasing force of the valve opening spring 45, as shown in Figure 5. Then, the valve body holder 19, which was pressed down by the operating rod 48, rises due to the biasing force of the valve closing spring 49, and the pilot valve body 18 seats on the pilot valve seat 17, closing the pilot passage 72. When the pilot passage 72 is closed, the refrigerant flowing into the interior (upper side) of the main valve body 74 through the pressure equalization passage 75 accumulates on the upper side of the main valve body 74, eliminating the pressure difference between the upper and lower sides of the main valve body 74. As shown in Figure 6, the biasing force of the main valve closing spring 85 pushes the main valve body 74 down, causing it to seat on the main valve seat 78, and the main valve opening 77 is closed, resulting in a closed state. Furthermore, in this closed valve state, the internal pressure of the valve port 77 and the outflow passage 63 is lower than the pressure above the main valve body 74, and this, combined with the downward pressing force of the main valve closing spring 85, maintains the closed valve state.

[0072] [Third Embodiment] A solenoid valve according to a third embodiment of the present invention will be described with reference to Figures 7 and 8. This third embodiment is an embodiment of the second invention, and the solenoid valve 81 according to this embodiment, like the solenoid valve 11 according to the first embodiment, has the same height h1 of the valve body 12 excluding the flange portion 24 and the overall height h of the solenoid valve including the sleeve 42 as a normally closed type solenoid valve, so that the coil can be shared with a normally closed type solenoid valve, but the valve body 12 is made of a single component.

[0073] Specifically, as shown in Figures 7 and 8, in the solenoid valve 81 of this embodiment, the valve body 12 is a single component comprising a flange portion 24, a fitting portion 22, and a cylinder portion 34.

[0074] Furthermore, in the first embodiment, a gap (flow channel gap) 37 was provided between the outer body 21 (fitting portion 22) and the inner body 31 (body portion 33 and the upper end of the cylinder portion 34) to form an outlet passage 15 for refrigerant to flow out of the valve body 12. However, in this embodiment, instead of the flow channel gap 37, a flow channel groove 82 extending in the vertical direction is formed on the outer circumferential surface of the fitting portion 22, and a horizontal flow channel portion 36 is formed inside the fitting portion 22 so as to open (communicate) with this flow channel groove 82. Therefore, in the solenoid valve 81 of this embodiment, the refrigerant in the valve chamber 13 is discharged to the outside of the valve body 12 by passing through the valve port 16, the horizontal flow channel portion 36, and the flow channel groove 82 in that order.

[0075] Other configurations and the opening and closing operation of the solenoid valve 81 are the same as those of the solenoid valve 11 in the first embodiment. In the second embodiment, the solenoid valve 11 of the first embodiment was used as the pilot valve, but it is also possible to configure a pilot-operated solenoid valve by using the solenoid valve 81 of this embodiment as the pilot valve instead.

[0076] Although embodiments of the present invention have been described above, it will be apparent to those skilled in the art that the present invention is not limited thereto and that various modifications can be made within the scope of the claims. [Explanation of symbols]

[0077] A Center axis F Refrigerant flow 11,81,91 Solenoid valve 12,92 Valve body 13,93 valve chamber (pilot valve chamber) 14,94 Inflow channel 15,95 Outflow channel 16,96 valve openings 17,97 valve seat (pilot valve seat) 18,98 Valve body (pilot valve body) 19 Valve holder 21 Outer body 22 Inset part 23 Male threaded section 24 Flange section 25 Through holes 26 Upper enlarged diameter part 27 Reduced diameter part 28 Lower enlarged diameter section 29. Sealing material (gasket) 31 Inner body 32 Fixed head 33 Torso 34 Cylinder section 35 Stopper section 36 Horizontal channel section 37 Flow channel gap 41 Electromagnetic drive device 42 sleeves 43 Plungers 44 Attractor 45. Valve opening spring 46 coils 47 Transmission Mechanism 48 Actuator Rod 49,99 valve closing spring 50 Spring retainer plate 61,61a Flow channel block 62 Inflow hole 63 Outflow hole 64 valve mounting holes 65 Upper hole 66 Pilot hole 67 Multilayered section 68 Step space 69 Communication path 70 Female thread section 71. Sealing material (O-ring) 72 Pilot passage 73 Main valve chamber 74 Main valve body 75 Pressure Equalizing Path 76 Main valve closing spring 77 Main valve opening 78 Main valve seat 82 Flow channel groove 85 Main valve closing spring

Claims

1. A valve body having a valve chamber, an inlet passage for introducing fluid into the valve chamber, an outlet passage for releasing the fluid from the valve chamber, and a valve seat formed within the valve chamber, A valve body that moves back and forth relative to the valve seat, An electromagnetic drive device for driving the valve body, Equipped with, When the direction from the valve seat toward the electromagnetic drive device is defined as "up", the direction from the electromagnetic drive device toward the valve seat is defined as "down", and the position in the vertical direction is defined as "height position", The electromagnetic drive device, A sleeve is provided that rises upward from the upper surface of the valve body, A plunger is housed within the sleeve so as to be slidable in the vertical direction, A suction element fixed to the upper end of the sleeve and used to suck the plunger, A valve opening spring that biases the plunger downward, has It is a solenoid valve, The valve body is An outer body having a ring-shaped main body portion and a through hole extending vertically in the center, An inner body fixed within the through hole, It has, The aforementioned internal body is A fixing head that is fitted into the through hole and fixes the inner body to the outer body, A body portion is positioned below the fixed head portion and at a height that overlaps with the main body portion in the vertical direction, A cylindrical portion formed on the lower side of the aforementioned body, It has, The valve chamber is formed at the upper inner end of the cylinder portion, The body portion has a valve opening that opens toward the valve chamber, The valve seat is formed at the lower end of the valve opening. The valve body is positioned in the valve chamber so as to face the US valve seat, A fluid passage gap is formed between the outer circumferential surface of the body and the inner circumferential surface of the main body, through which the fluid can pass. A valve holder supports the valve body within the cylinder portion so that it can slide vertically, A transmission mechanism that transmits the vertical movement of the plunger to the valve body via the valve body holder and causes the valve body to move up and down together with the plunger, Furthermore, The inflow passage is formed to communicate with the valve chamber, extending from the lower surface of the cylinder portion, through the space between the outer circumferential surface of the valve holder and the inner circumferential surface of the cylinder portion. The outflow passage includes a connecting passage formed in the body so as to connect the valve opening and the gap between the flow paths. A solenoid valve characterized by the following features.

2. The aforementioned transmission mechanism is An operating rod extends vertically through the fixed head and the body, and is interposed between the plunger and the valve body holder, thereby lowering the valve body by transmitting the downward movement of the plunger to the valve body holder. A valve closing spring biases the valve holder upward and raises the valve body via the valve holder when the plunger moves upward, including The solenoid valve according to claim 1.

3. The operating rod is configured such that when the plunger is attracted to and contacts the suction element and the valve body is seated on the valve seat during valve closing, a gap is formed between the plunger and the plunger or between the operating rod and the valve body holder. The solenoid valve according to claim 2.

4. The solenoid valve is a solenoid valve that can be mounted on a flow path block by fitting the main body into the valve mounting hole of the flow path block, which has an inlet hole for introducing the fluid, an outlet hole for releasing the fluid, and a valve mounting hole capable of receiving the solenoid valve. When the main body is fitted into the valve mounting hole, The aforementioned inlet passage is in communication with the aforementioned inlet hole, The gap between the flow channels is in communication with the outflow hole. The solenoid valve according to any one of claims 1 to 3.

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