JP7487946B2 - Electrically operated valve - Google Patents

Description

The present invention relates to an electrically driven valve, and in particular to a valve body structure that can prevent valve leakage even when a moving body such as a plunger that supports the valve body in a solenoid valve or motor-operated valve tilts when the valve is closed.

Electrically driven valves, which use an electrical drive device such as a solenoid or electric motor to open and close the valve, are used in refrigeration cycle equipment with a refrigerant circuit, such as air conditioners, refrigeration units, and freezing units.

In such electrically driven valves, the valve element that opens and closes the refrigerant flow path is supported by a moving body (such as a plunger or valve stem) that is slidable in the opening and closing direction (axial direction) of the valve. For example, in a solenoid valve, the plunger is moved by a solenoid or compression coil spring, and in a motor-operated valve, the valve is opened and closed by moving the valve stem with a lifting device that uses an electric motor.

Another document that discloses such an electrically driven valve is the following Patent Document 1:

JP 2017-160983 A

The moving body that supports the valve body is housed in a cylindrical member (sleeve) and is guided by the cylindrical member to prevent it from shifting sideways, but a certain clearance is provided between the moving body and the inner surface of the cylindrical member to allow sliding.

However, such valves are not necessarily installed so that the axis of the valve is vertical in the refrigerant circuit. Depending on the piping space and the direction in which the piping is routed, the valves may be installed at an angle or even lying on their side.

As a result, the moving body that slides inside the sleeve may tilt during the valve closing operation, and this tilt may also cause the valve disc supported by the moving body to tilt, creating a gap between the valve seat and the valve disc, which may result in valve leakage.

On the other hand, in order to prevent such valve leakage, an elastic material is used for the valve body so that the inclination of the valve body when the valve is closed can be absorbed.

However, the use of elastic materials has the drawback of reducing the durability of the valve body, and further solutions are needed.

However, the invention described in Patent Document 1 does not solve the valve leakage problem described above.

Therefore, the object of the present invention is to present a new valve body structure that does not cause valve leakage even if the moving body supporting the valve body is tilted.

In order to solve the above problems and achieve the object, the electrically driven valve according to the first invention of the present application comprises a valve body having a main valve chamber and a pilot valve chamber therein, an inflow passage for introducing a refrigerant into the main valve chamber, an outflow passage for discharging the refrigerant from the main valve chamber, a valve port having a main valve seat and provided between the outflow passage and the main valve chamber so as to open into the main valve chamber, a main valve body that moves forward and backward relative to the main valve seat to open and close the valve port, a pilot passage that passes through the main valve body and selectively connects the pilot valve chamber and the outflow passage, a pressure equalizing passage that connects the main valve chamber and the pilot valve chamber, a pilot valve seat formed at the end of the pilot passage on the pilot valve chamber side, and The electrically driven valve includes a pilot valve body that moves forward and backward relative to the pilot valve seat to open and close the pilot passage, a moving body that holds the pilot valve body and moves together with the pilot valve body, a valve receiving member that is interposed between the pilot valve body and the moving body and transmits a pressing force to the pilot valve body that presses the pilot valve body against the pilot valve seat to close the pilot passage, and an electric drive device that drives the pilot valve body via the moving body, and a point contact portion where a convex curved surface and a flat surface or two convex curved surfaces contact each other is formed between the pilot valve body and the valve receiving member, and the pressing force is transmitted from the valve receiving member to the pilot valve body via the point contact portion.

The term "selectively connect" the pilot passage means that it is not always connected, but is opened and closed by the pilot valve body. When the electrically driven valve is closed, the pilot valve body is seated on the pilot valve seat and the pilot passage is closed, and when the electrically driven valve is opened, the pilot valve body is separated from the pilot valve seat and the pilot passage is opened (the same applies to the second invention described below). On the other hand, the pressure equalizing passage is always open, connecting the main valve chamber and the pilot valve chamber. The pressure equalizing passage has a smaller cross-sectional area (flow passage area) than the pilot passage. The opening and closing operation of the electrically driven valve will be described in detail in the description of the embodiment below.

The electrically driven valve according to the first invention of this application relates to a pilot type driven valve that controls a main valve via a pilot valve driven by an electrically driven device. In this driven valve, a point contact is formed between the pilot valve body and a valve receiving member that transmits a pressure force to the pilot valve body by pressing the pilot valve body against the pilot valve seat to close the pilot valve, and the pressure force when the valve is closed is transmitted to the pilot valve body via this point contact.

The point contact portion is formed on the surface of the valve receiving member that transmits the pressing force (the surface in contact with the pilot valve body) and the surface of the pilot valve body to which the pressing force is transmitted (the surface in contact with the valve receiving member). The point contact portion may be in any of the following forms: (1) the surface of the valve receiving member is a convex surface and the surface of the pilot valve body is a flat surface; (2) the surface of the valve receiving member is a flat surface and the surface of the pilot valve body is a convex surface; or (3) both the surface of the valve receiving member and the surface of the pilot valve body are convex surfaces.

By bringing the valve receiving member and pilot valve body (hereinafter sometimes simply referred to as "valve body") into contact via such a point contact, unlike when flat surfaces are in contact with each other, even if the moving body tilts, the tilt fluctuation is not transmitted to the pilot valve body via the valve receiving member, and the pilot valve body is prevented from tilting together with the moving body and valve receiving member when the valve is closed, which makes it possible to prevent valve leakage (refrigerant leaking into the outflow passage through the pilot passage).

Note that a "convex surface" is typically a spherical surface, but is not limited to this and may be, for example, a paraboloid or other convex curved surface.

In addition, according to the present invention (the first invention above and the second to fourth inventions described below; the term "the present invention" refers to all of the first to fourth inventions), there is no longer a need to use an elastic material for the valve body (pilot valve body) to avoid valve leakage as in the past, and durability can be improved by forming the pilot valve body from a hard material.

In the present invention, an "electrical drive device" is typically an electromagnetic actuator that moves a moving body (plunger) by the magnetic force generated by a solenoid. However, the moving body may also be moved by an electric motor, and the electric drive device also includes an electric motor.

In the present invention, the "pressing force" may be a force generated by an electrical drive device (e.g., an electromagnetic actuator or an electric motor) (e.g., a magnetic force generated by a solenoid, or a linear force obtained by converting the rotational force generated by an electric motor into linear motion), or it may be a force generated by a mechanical part (e.g., a coil spring) that is not an electrical drive device (e.g., the elastic force of a compression coil spring). In the first invention above (as well as the third invention described below), these forces are received by the valve receiving member and transmitted to the pilot valve body as a pressing force.

The valve receiving member can be, for example, a plate-shaped member with a flat surface on the side that contacts the moving body and a convex curved surface on the side that contacts the pilot valve body.

The valve receiving member may also be a plate-like member (thin plate member) with a central portion recessed toward the pilot valve body to form a convex curved surface portion that protrudes toward the pilot valve body. Such a valve receiving member can be manufactured by press working, and the use of such a valve receiving member has the advantage of reducing the manufacturing costs of the electrically driven valve.

Furthermore, the valve receiving member can be a spherical member.

The electrically driven valve according to the second invention of the present application is a pilot type driven valve similar to the first invention, but does not have a valve receiving member and forms a point contact between the moving body and the pilot valve body.

Specifically, the electrically driven valve comprises a valve body having a main valve chamber and a pilot valve chamber therein, an inflow passage for introducing refrigerant into the main valve chamber, an outflow passage for discharging refrigerant from the main valve chamber, a valve port having a main valve seat and provided between the outflow passage and the main valve chamber so as to open into the main valve chamber, a main valve body that moves forward and backward relative to the main valve seat to open and close the valve port, a pilot passage that passes through the main valve body and selectively connects the pilot valve chamber to the outflow passage, a pressure equalizing passage that connects the main valve chamber to the pilot valve chamber, a pilot valve seat formed at the end of the pilot passage on the pilot valve chamber side, and a pilot valve body. An electrically driven valve includes a pilot valve body that moves back and forth relative to the pilot valve seat to open and close the pilot passage, a moving body that holds the pilot valve body and moves together with the pilot valve body, and transmits a pressing force to the pilot valve body to press the pilot valve body against the pilot valve seat to close the pilot passage, and an electric drive device that drives the pilot valve body via the moving body. A point contact portion where a convex curved surface and a flat surface or two convex curved surfaces contact each other is formed between the pilot valve body and the moving body, and the pressing force is transmitted from the moving body to the pilot valve body via the point contact portion.

In the electrically driven valve according to the second invention of the present application, the pressing force is transmitted directly from the moving body to the pilot valve body without going through a valve receiving member. However, by forming a point contact between the moving body and the pilot valve body, it is possible to prevent the pilot valve body from tilting even if the moving body tilts when the valve is closed, as in the first invention, and to prevent valve leakage.

In the second invention, the point contact portion is formed on the surface of the moving body that transmits the pressing force (the surface in contact with the pilot valve body) and the surface of the pilot valve body to which the pressing force is transmitted (the surface in contact with the moving body). Any of the following may be adopted: (1) the surface of the moving body is a convex surface and the surface of the pilot valve body is a flat surface; (2) the surface of the moving body is a flat surface and the surface of the pilot valve body is a convex surface; or (3) both the surface of the moving body and the surface of the pilot valve body are convex surfaces.

Furthermore, the present invention can also be applied to direct-acting valves, and the electrically driven valve according to the third invention of the present application is a direct-acting valve equipped with a valve receiving member.

Specifically, the electrically driven valve according to the third invention comprises a valve body having a valve chamber therein, a first flow path which is one of an inflow path for introducing refrigerant into the valve chamber and an outflow path for discharging refrigerant from the valve chamber, a second flow path which is the other of the inflow path for introducing refrigerant into the valve chamber and the outflow path for discharging refrigerant from the valve chamber, a valve port which has a valve seat and is provided between the first or second flow path and the valve chamber so as to open into the valve chamber, and a closing valve which is pressed against the valve seat by receiving a pressing force in the valve closing direction to close the valve port. An electrically driven valve includes a valve body that moves forward and backward relative to the valve seat between a valve position and an open position where the valve is separated from the valve seat to open the valve port, a moving body that holds the valve body and moves together with the valve body, a valve receiving member that is interposed between the moving body and the valve body and transmits the pressing force to the valve body, and an electric drive device that drives the valve body via the moving body, and a point contact portion where a convex curved surface and a flat surface or two convex curved surfaces contact each other is formed between the valve body and the valve receiving member, and the pressing force is transmitted from the valve receiving member to the valve body via the point contact portion.

In this type of direct acting valve, as in the pilot type valve, the inclination of the moving body can be prevented from being transmitted to the valve body, and valve leakage (leakage of refrigerant from the valve chamber into the outflow path) can be prevented.

In the third invention, as in the first invention, the valve receiving member may be (1) a plate-shaped member with a flat surface on the side that contacts the moving body and a convex surface on the side that contacts the valve body, (2) a plate-shaped member with a central portion recessed toward the valve body to form a convex surface portion that protrudes toward the valve body, or (3) a spherical member.

Furthermore, the electrically driven valve according to the fourth aspect of the present invention is a direct acting type valve like the third aspect of the present invention, but does not have a valve receiving member.

Specifically, the electrically driven valve according to the fourth aspect of the invention is an electrically driven valve comprising: a valve body having a valve chamber therein; a first flow path which is one of an inlet path for introducing a refrigerant into the valve chamber and an outlet path for discharging the refrigerant from the valve chamber; a second flow path which is the other of the inlet path for introducing the refrigerant into the valve chamber and the outlet path for discharging the refrigerant from the valve chamber; a valve port which has a valve seat and is provided between the first or second flow path and the valve chamber so as to open into the valve chamber; a valve disc which receives a pressing force in a valve closing direction and moves back and forth relative to the valve seat between a valve closing position where it is pressed against the valve seat to close the valve port and a valve opening position where it is moved away from the valve seat to open the valve port; a moving body which holds the valve disc and moves together with the valve disc; and an electrically driven device which drives the valve disc via the moving body, wherein a point contact portion where the convex curved surfaces come into contact is formed between the valve disc and the moving body, and the pressing force is transmitted from the moving body to the valve disc via the point contact portion.

According to the present invention, even if the moving body supporting the valve body tilts during the valve closing operation, the valve body can be prevented from tilting, and valve leakage can be prevented.

Other objects, features, and advantages of the present invention will become apparent from the following description of the embodiments of the present invention, which are given with reference to the drawings. Note that the same reference numerals in each drawing indicate the same or corresponding parts.

FIG. 1 is a vertical cross-sectional view showing a solenoid valve (closed state) according to a first embodiment of the present invention. FIG. 2 is an enlarged vertical cross-sectional view showing a main portion (plunger and pilot valve portion) of the solenoid valve (closed state) according to the first embodiment. FIG. 3 is a vertical cross-sectional view showing a state of main parts (plunger and pilot valve portion) in the solenoid valve according to the first embodiment when the plunger is tilted when the valve is closed. FIG. 4 is a vertical cross-sectional view showing a state of main parts (plunger and pilot valve portion) in a conventional solenoid valve when the plunger is tilted when the valve is closed, for comparison with the solenoid valve according to the first embodiment. FIG. 5 is a vertical sectional view showing a modification of the main portion (plunger and pilot valve portion) of the solenoid valve (closed state) according to the first embodiment. FIG. 6 is a vertical sectional view showing another example of the configuration of the main parts (plunger and pilot valve portion) of the solenoid valve (closed state) according to the first embodiment. FIG. 7 is a vertical sectional view showing still another example of the configuration of the main parts (plunger and pilot valve portion) of the solenoid valve (closed state) according to the first embodiment. FIG. 8 is a vertical sectional view showing still another example of the configuration of the main parts (plunger and pilot valve portion) of the solenoid valve (closed state) according to the first embodiment. FIG. 9 is a vertical sectional view showing still another example of the configuration of the main parts (plunger and pilot valve portion) of the solenoid valve (closed state) according to the first embodiment. FIG. 10 is a vertical sectional view showing still another example of the configuration of the main parts (plunger and pilot valve portion) of the solenoid valve (closed state) according to the first embodiment. FIG. 11 is a vertical cross-sectional view showing a solenoid valve (closed state) according to a second embodiment of the present invention.

First Embodiment
1 and 2, an electrically driven valve 11 according to a first embodiment of the present invention is a solenoid valve that includes a valve portion 12 that opens and closes a refrigerant flow path and an electromagnetic actuator 13 that drives the valve portion 12, and controls the flow of refrigerant in a refrigeration cycle device such as a heat pump type heating and cooling system. The solenoid valve 11 is a pilot type solenoid valve that uses a pilot valve to control a main valve that opens and closes the refrigerant flow path, and is a normally closed type valve that is in a closed state when power is not supplied to the electromagnetic actuator 13.

In addition, in each figure, mutually orthogonal two-dimensional coordinates representing the up/down and left/right directions are appropriately displayed, and the following explanation will be based on these directions, but the solenoid valve of this invention and each embodiment can be used in various orientations, and each direction is for the convenience of explanation and does not impose any limitations on the configuration of each part of the present invention.

The valve section 12 includes a valve body 21 installed in a housing member 14 having an inlet passage 15 and an outlet passage 16 for the refrigerant, a main valve (main valve body 23 and main valve seat 18, etc.) provided in a main valve chamber 22 within the valve body 21, and a pilot valve (pilot valve body 31 and pilot valve seat 25, etc.) provided in a pilot valve chamber 27 within the valve body 21 to control the main valve.

The valve body 21 is a cylindrical member with openings on the top and bottom (top opening 21a and bottom opening 21b). After being inserted into the valve mounting hole 14a of the housing member 14, the periphery of the valve mounting hole 14a is crimped and then brazed (see reference numeral 19 in FIG. 1) to secure it to the housing member 14.

The lower space within the valve body 21 is the main valve chamber 22, which is connected to the inlet passage 15 and outlet passage 16 of the housing member 14. That is, the end of the outlet passage 16 on the valve body 21 side is provided with a valve port 17 that stands vertically upward and protrudes into the main valve chamber 22 from the bottom opening 21b of the valve body 21, and the upper surface of this valve port 17 is used as an outlet port for flowing the refrigerant from the main valve chamber 22 to the outlet passage 16, and is used as the main valve seat 18 with which the main valve body 23 comes into contact (abuts and separates). In addition, the opening portion of the bottom opening 21b of the valve body 21 around the valve port 17 is used as an inlet port for flowing the refrigerant from the inlet passage 15 into the main valve chamber 22.

The main valve chamber 22 is provided with a main valve body 23, which has a cylindrical overall shape and is slidably inserted into the valve body 21 (positioned so that it can move forward and backward relative to the main valve seat 18). The main valve body 23 is also biased upward by a valve-opening spring 26 provided in the main valve chamber 22. The valve-opening spring 26 is a compression coil spring installed in a compressed state between the peripheral edge of the bottom surface of the valve body 21 and a step 23a formed on the outer peripheral surface of the lower part of the main valve body 23.

The main valve body 23 also has a pilot passage 24 that passes through the center of the main valve body 23 in the direction of the axis A (vertical direction) and connects the main valve chamber 22 and the pilot valve chamber 27, and also has a pressure equalization passage (not shown) that connects the main valve chamber 22 and the pilot valve chamber 27 but has a smaller diameter than the pilot passage 24. The pressure equalization passage is not opened or closed and always connects the main valve chamber 22 and the pilot valve chamber 27, but the pilot passage 24 is opened and closed by the pilot valve body 31 described below. The pressure equalization passage in this embodiment is the gap between the main valve body 23 and the inner peripheral surface of the valve body 21. The main valve chamber 22 in this embodiment is the space between the main valve body 23 and the main valve seat 18 and the space facing the inlet passage 15, and the pilot valve chamber 27 in this embodiment is the space formed above the main valve body 23.

A pilot valve chamber 27 is formed on the upper surface of the main valve body 23, and a pilot valve is provided. Specifically, a pilot valve seat 25 is formed in the center of the upper surface of the main valve body 23 (the upper end of the pilot passage 24) where the pilot passage 24 opens into the pilot valve chamber 27, and a pilot valve body 31 is provided so as to be movable toward and away from the pilot valve seat 25. The pilot valve body 31 is held at the lower end of a plunger 44, which acts as a moving body, as described below, and opens and closes the pilot passage 24 by moving up and down together with the plunger 44.

On the other hand, the electromagnetic actuator 13 has a coil 41 wound around a bobbin 42, an attractor 43 arranged inside the coil 41, and a plunger 44 that is attracted to the attractor 43 by the magnetic force generated by the coil 41. The bobbin 42 has a cylindrical part in the center, and the attractor 43 and plunger 44 are arranged inside this cylindrical part while being housed in a sleeve 51.

The sleeve 51 is a cylindrical member with no bottom or lid (both the top and bottom are open), with its upper end fixed to the outer periphery of the suction element 43 so that the top is closed by the suction element 43, while its lower end is fixed to the top of the valve body 21 by being inserted into the valve body 21 through the top opening 21a of the valve body 21.

The plunger 44 is housed inside the sleeve 51 (below the suction element 43) so that it can slide up and down. In addition, a valve-closing spring 45 made of a compression coil spring is provided between the suction element 43 and the plunger 44, and this valve-closing spring 45 urges the plunger 44 downward in the valve-closing direction.

At the lower end of the plunger 44, a valve body holding hole 44a is formed to hold the pilot valve body 31 together with the valve receiving member 32, and the valve receiving member 32 and the pilot valve body 31 are stacked vertically in the valve body holding hole 44a so that the valve receiving member 32 is on the upper side and the pilot valve body 31 is on the lower side. Then, a ring-shaped retaining ring 34 that abuts on the lower peripheral edge of the pilot valve body 31 is placed on the lower surface of the pilot valve body 31, and then the lower end peripheral portion 44b (see FIG. 2) of the valve body holding hole 44a is crimped to fix the retaining ring 34. The retaining ring 34 supports the lower peripheral portion of the pilot valve body 31 from below so as not to hinder the approach and separation of the pilot valve body 31 from the pilot valve seat 25, and prevents the pilot valve body 31 and the valve receiving member 32 from falling downward (outside the valve body holding hole 44a).

In this embodiment, a valve receiving spring 46 is provided on the upper surface of the valve receiving member 32 so as to be interposed between the valve receiving member 32 and the plunger 44. This valve receiving spring 46 is a compression coil spring that is accommodated in a compressed state in a hole 44c formed at the back (center of the upper surface) of the valve body holding hole 44a to urge the valve receiving member 32 and the pilot valve body 31 downward, and serves to cushion the impact when the valve is closed (when the pilot valve body 31 seats on the pilot valve seat 25).

The pilot valve body 31 has a disk-like shape with both the upper surface 31a and the lower surface 31b being flat (planar), but the valve receiving member 32, which is placed in contact with the upper surface 31a of the pilot valve body 31, is a disk-like member with a flat upper surface 32a and a spherical lower surface 32b that protrudes downward (towards the pilot valve body 31). Therefore, the valve receiving member 32 and the pilot valve body 31 are in contact with each other at the spherical surface (the lower surface 32b of the valve receiving member 32) and the flat surface (the upper surface 31a of the pilot valve body 31), and the point contact portion 33 referred to in the present invention is formed between the valve receiving member 32 and the pilot valve body 31. The spherical surface of the lower surface 32b of the valve receiving member can be formed by, for example, cutting. The effect of the point contact portion 33 will be described in detail later.

The operation of the solenoid valve 11 in this embodiment is as follows.

In the closed valve state shown in FIG. 1, the pilot valve body 31 is seated on the pilot valve seat 25 and the pilot passage 24 is closed, so that the internal pressure of the pilot valve chamber 27, which is connected to the main valve chamber 22 via a pressure equalization path, is equal to that of the main valve chamber 22, while the pressure in the valve orifice 17 is lower than that of the main valve chamber 22. This pressure difference (more precisely, the difference between the pressure in the pilot valve chamber 27 and the pressure in the valve orifice 17) causes the main valve body 23 to seat on the main valve seat 18, maintaining the closed valve state.

When the coil 41 of the electromagnetic actuator 13 is energized, the plunger 44 is attracted by the attractor 43 and rises against the biasing force of the valve-closing spring 45, and the pilot valve body 31 moves away from the pilot valve seat 25 and the pilot passage 24 is opened. As a result, the refrigerant introduced into the pilot valve chamber 27 through the pressure equalizing passage is discharged to the outflow passage 16 through the pilot passage 24, and the pressure in the pilot valve chamber 27 drops and becomes lower than the pressure in the main valve chamber 22 (inflow passage 15). Then, the main valve body 23 is lifted by the pressure difference between the pilot valve chamber 27 and the main valve chamber 22 and the upward biasing force of the valve-opening spring 26, and the valve opening 17 is opened and the valve is opened. The refrigerant that has flowed into the main valve chamber 22 from the inflow passage 15 (see arrow F1) flows out of the main valve chamber 22 through the valve opening 17 and into the outflow passage 16 (see arrow F2).

The main valve body 23 is pushed up and stops when it hits the lower end peripheral portion 21c of the upper opening 21a of the valve body 21. Therefore, the pilot valve seat 25 at the center of the upper surface of the main valve body abuts against the lower surface of the pilot valve body 31, and the pilot passage 24 is not closed, but remains open.

On the other hand, when the current to the coil 41 is stopped in this open state, the suction force of the suction element 43 disappears and the plunger 44 is released from the suction element 43, so that the plunger 44 is pushed back downward by the valve-closing spring 45, the pilot valve element 31 seats on the pilot valve seat 25, and the pilot passage 24 is closed. Then, the refrigerant flowing into the pilot valve chamber 27 through the pressure equalizing path accumulates in the pilot valve chamber 27, increasing the pressure in the pilot valve chamber 27, and the main valve element 23 is pushed down against the biasing force of the valve-opening spring 26 by the pressure difference between the pilot valve chamber 27 and the main valve chamber 22, and it seats on the main valve seat 18, closing the valve port 17 and entering a closed state (see FIG. 1).

Now, referring to Figures 3 and 4, the effect of the point contact portion 33 will be described. As shown in Figure 4, in a conventional solenoid valve, when the valve is closed, the pilot valve body 31 and the plunger 44 come into contact with each other at their flat surfaces (the contact portion is indicated by the symbol 33a), so when the plunger 44 (the central axis of the plunger is indicated by the symbol A1) tilts, the pilot valve body 31 also tilts. For this reason, in the conventional solenoid valve, a gap S is generated between the pilot valve seat 25 and the pilot valve body 31, causing valve leakage.

In contrast, with the solenoid valve of this embodiment, as shown in FIG. 3, the valve receiving member 32 is interposed between the plunger 44 and the pilot valve body 31, and the valve receiving member 32 and the pilot valve body 31 are in contact via the point contact portion 33. Therefore, even if the plunger 44 tilts, the tilt is not transmitted to the pilot valve body 31, and the pilot valve body 31 sits horizontally on the pilot valve seat 25. Therefore, no gap occurs between the pilot valve seat 25 and the pilot valve body 31, and valve leakage can be prevented.

A modified version of this embodiment will be described.

In the above embodiment, as shown in FIG. 5, the valve receiving member 32 may be provided with a protrusion 32c that protrudes upward from the upper surface of the valve receiving member 32 and fits into the lower part of the valve receiving spring 46. Providing such a protrusion 32c prevents the valve receiving member 32 from shifting sideways, and makes it possible to more stably bring the valve receiving member 32 into contact with the pilot valve body 31. On the other hand, as shown in FIG. 6, it is also possible to configure the plunger 44 without a valve receiving spring.

Furthermore, regarding a modified example of the point contact portion 33, it is also possible to fabricate the valve receiving member 32 by pressing a metal plate as shown in FIG. 7. This valve receiving member 32 is formed by forming a convex curved surface portion protruding toward the pilot valve body 31 side by pressing the center of a metal disk (a thin metal plate having a circular planar shape) downward. With this type of valve receiving member 32, the valve receiving member 32 can be fabricated in a short time and at low cost compared to forming the valve receiving member 32 by cutting as described above, making it possible to reduce the manufacturing cost of the solenoid valve 11.

Also, as shown in FIG. 8, a similar point contact portion 33 can be formed by making the lower surface of the plunger 44, i.e., the top surface (upper surface) of the valve body holding hole 44a, which is the contact surface with the upper surface of the pilot valve body 31, a downwardly protruding spherical surface and bringing this spherical surface into contact with the upper surface of the pilot valve body 31, without providing a valve receiving member.

Conversely, as shown in FIG. 9, the plunger 44 side may be flat and the pilot valve body 31 side may be spherical; more specifically, the top surface of the valve body holding hole 44a may be flat, but the top surface 31a of the pilot valve body 31 may be a spherical surface that protrudes upward, so that the plunger 44 (top surface of the valve holding hole 44a) and the top surface of the pilot valve body 31 come into contact with each other to form a point contact portion 33.

Furthermore, as shown in FIG. 10, a spherical valve receiving member 32 is placed on the top of the valve receiving hole 44a, and the pilot valve body 31 is provided in the valve receiving hole 44a of the plunger 44 so that the upper surface 31a of the pilot valve body 31 comes into contact with the bottom of the spherical valve receiving member 32, thereby forming a point contact portion 33 in a similar manner.

Second Embodiment
A solenoid valve according to a second embodiment of the present invention will be described with reference to FIG.

As shown in FIG. 11, the solenoid valve 61 according to the second embodiment of the present invention is a normally closed type solenoid valve in which the valve portion 12 that opens and closes the refrigerant flow path is driven by an electromagnetic actuator 13, as in the first embodiment. However, unlike the first embodiment, it is a direct acting solenoid valve that directly (without a pilot valve) drives the valve body 62 that opens and closes the refrigerant flow path.

Specifically, the solenoid valve 61 of this embodiment has a valve body 21 with a valve chamber 22 therein as a valve portion 12 that opens and closes the refrigerant flow path, an inflow passage 15 that allows the refrigerant to flow into the valve chamber 22, an outflow passage 16 that allows the refrigerant to flow out of the valve chamber 22, a valve port 17 formed between the outflow passage 16 and the valve chamber 22, a valve seat 18 formed on the upper surface of the valve port 17, and a valve body 62 that moves back and forth (up and down) relative to the valve seat 18 to open and close the valve port 17.

The inlet passage 15 is connected to the side of the valve body 21 so as to communicate with the valve chamber 22. Meanwhile, the outlet passage 16 is connected to the bottom surface (lower surface) of the valve body 21 and communicates with the valve chamber 22 via a valve port 17 formed to rise vertically upward from the bottom surface of the valve body 21 into the valve chamber 22.

The solenoid valve 61 also has, as the electromagnetic actuator 13 that drives the valve section 12, a coil 41 wound around a bobbin 42, an attractor 43 disposed inside the coil 41, and a plunger 44 that is attracted to the attractor 43 by the magnetic force generated by the coil 41. The bobbin 42 has a cylindrical section in the center, and the attractor 43 and plunger 44 are disposed within this cylindrical section while being housed in a sleeve 51.

The sleeve 51 is a cylindrical member with no bottom or lid, and its upper end is fixed to the outer periphery of the suction element 43 so that the upper surface is closed by the suction element 43, while its lower end is fixed to the top of the valve body 21 by being inserted into the valve body 21 through the upper opening 21a of the valve body 21.

The plunger 44 is housed in the sleeve 51 (below the suction element 43) so that it can slide up and down. The plunger 44 also has a spring housing hole 44d that passes through the center in the up and down direction and communicates with the valve body holding hole 44a at the bottom end of the plunger, and the valve closing spring 45 is provided in this spring housing hole 44d. The valve closing spring 45 is a compression coil spring that is arranged in a compressed state between the valve receiving member 32 housed in the valve body holding hole 44a and the suction element 43, and urges the valve body 62, which is arranged in the valve body holding hole 44a, downward (in the valve closing direction) via the valve receiving member 32.

The structure for holding the valve body 62 and the valve receiving member 32 relative to the plunger 44 is the same as in the first embodiment. That is, the valve receiving member 32 and the valve body 62 are stacked vertically and accommodated in the valve body holding hole 44a at the bottom end of the plunger, with the valve receiving member 32 on the top and the valve body 62 on the bottom, and the lower periphery of the valve body holding hole 44a is crimped to fix the retaining ring 34, thereby holding the valve body 62 and the valve receiving member 32 in the valve body holding hole 44a.

In this embodiment, the valve body 62 has a disk-like shape with flat (planar) upper and lower surfaces, similar to the pilot valve body 31 in the first embodiment, and the valve receiving member 32, which is placed in contact with the upper surface of the valve body 62, is a disk-like member with a flat (planar) upper surface and a spherical lower surface that protrudes downward (towards the valve body 62). Therefore, a point contact portion 33 is formed between the valve receiving member 32 and the valve body 62, where the spherical surface (the lower surface of the valve receiving member 32) and the flat surface (the upper surface of the valve body 62) come into contact.

In this embodiment, the various modifications (FIGS. 5 and 6 to 10) described in the first embodiment can also be applied to the valve receiving member and the point contact portion between the valve receiving member and the valve body.

The operation of the solenoid valve 61 in this embodiment is as follows.

In the closed valve state shown in FIG. 11, the valve-closing spring 45 presses down the valve body 62 together with the plunger 44 via the valve receiving member 32, and the valve body 62 is pressed against the valve seat 18 to close the valve port 17.

When the coil 41 of the electromagnetic actuator 13 is energized, the plunger 44 is attracted by the attractor 43 and rises against the biasing force of the valve-closing spring 45, the valve body 62 is lifted away from the valve seat 18, and the valve opening 17 is opened to an open state. Then, the refrigerant (see arrow F1) that has flowed into the valve chamber 22 from the inlet passage 15 flows out from the valve chamber 22 through the valve opening 17 to the outlet passage 16 (see arrow F2).

On the other hand, when the current to the coil 41 is stopped from this open state, the suction force of the attractor 43 is lost and the plunger 44 is released from the attractor 43, so that the valve body 62 together with the plunger 44 is pushed downward by the valve closing spring 45 via the valve receiving member 32, and the valve body 62 is seated on the valve seat 18, closing the valve orifice 17 and entering a closed state (see FIG. 11).

In the solenoid valve 61 of this embodiment, as in the solenoid valve 11 of the first embodiment, even if the plunger 44 tilts during the valve closing operation, the point contact portion 33 is formed between the valve receiving member 32 and the valve body 62, so the tilt of the plunger 44 is not transmitted to the valve body 62, and the valve body 62 is seated horizontally on the valve seat 18, preventing valve leakage.

The above describes the embodiments of the present invention, but the present invention is not limited to these, and it will be clear to those skilled in the art that various modifications can be made within the scope of the claims.

For example, while the above embodiments are all normally closed type valves, the present invention can be similarly applied to normally open type valves. As already mentioned, the present invention is not limited to solenoid valves, but can also be applied to motor-operated valves driven by an electric motor. When applied to a motor-operated valve, a valve receiving member 32 and a valve body 62 can be provided at the tip of a lifting member (e.g., a valve stem or a valve rod) that acts as a moving body that is moved up and down by a lifting device using a screw feed mechanism, and the pilot passage 24 can be opened and closed by the valve body 62.

The electrically driven valve according to the present invention can be preferably used in refrigeration cycle devices equipped with a refrigerant circuit, such as air conditioners (air conditioners), freezers, and refrigerators, but is not limited to these, and the electrically driven valve according to the present invention can be used for a variety of other applications.

A: central axis of solenoid valve A1: central axis of plunger F1, F2: flow of refrigerant 1, 61: electrically driven valve (solenoid valve)
12 Valve portion 13 Electromagnetic actuator 14 Housing member 14a Valve mounting hole 15 Inflow passage 16 Outflow passage 17 Valve port 18 Valve seat (main valve seat)
19 Brazed portion 21 Valve body 21a Upper opening of valve body 21b Lower opening of valve body 21c Lower end peripheral portion of upper opening of valve body 22 Valve chamber (main valve chamber)
Description of the Reference Signs 23 Main valve body 23a Step portion 24 Pilot passage 25 Pilot valve seat 26 Valve-opening spring 27 Pilot valve chamber 31 Pilot valve body 31a Upper surface of pilot valve body 31b Lower surface of pilot valve body 32 Valve receiving member 32a Upper surface of valve receiving member 32b Lower surface of valve receiving member 33 Point contact portion 34 Retaining ring 41 Coil 42 Bobbin 43 Attractor 44 Plunger 44a Valve body retaining hole 44b Lower end peripheral portion of valve body retaining hole 44c Hole for accommodating valve receiving spring 44d Spring accommodating hole 45 Valve-closing spring 46 Valve receiving spring 51 Sleeve 62 Valve body

Claims (10)

a valve body having a main valve chamber and a pilot valve chamber therein;
an inflow passage for allowing a refrigerant to flow into the main valve chamber;
an outflow passage for causing the refrigerant to flow out from the main valve chamber;
a valve port having a main valve seat and disposed between the outlet passage and the main valve chamber so as to open into the main valve chamber;
a main valve body that moves toward and away from the main valve seat to open and close the valve port;
a pilot passage passing through the main valve body and selectively connecting the pilot valve chamber and the outflow passage;
a pressure equalizing passage that communicates the main valve chamber and the pilot valve chamber;
a pilot valve seat formed at an end of the pilot passage on the pilot valve chamber side;
a pilot valve body that moves back and forth relative to the pilot valve seat to open and close the pilot passage;
a moving body that holds the pilot valve body and moves together with the pilot valve body;
a valve receiving member interposed between the pilot valve body and the moving body, the valve receiving member pressing the pilot valve body against the pilot valve seat to transmit a pressing force to the pilot valve body for closing the pilot passage;
an electric drive device that drives the pilot valve body via the moving body,
a point contact portion where a convex curved surface and a flat surface or where two convex curved surfaces contact each other is formed between the pilot valve body and the valve receiving member,
the pressing force is transmitted from the valve receiving member to the pilot valve body via the point contact portion. The valve receiving member is
2. The electrically driven valve according to claim 1, wherein the valve is a plate-shaped member having a flat surface that contacts the movable body and a convex curved surface that contacts the pilot valve body. The valve receiving member is
2. The electrically driven valve according to claim 1, wherein the plate-shaped member has a central portion recessed toward the pilot valve body to form a convex curved surface portion protruding toward the pilot valve body. The electrically driven valve according to claim 1 , wherein the valve receiving member is a spherical member. a valve body having a main valve chamber and a pilot valve chamber therein;
an inflow passage for allowing a refrigerant to flow into the main valve chamber;
an outflow passage for causing the refrigerant to flow out from the main valve chamber;
a valve port having a main valve seat and disposed between the outlet passage and the main valve chamber so as to open into the main valve chamber;
a main valve body that moves toward and away from the main valve seat to open and close the valve port;
a pilot passage passing through the main valve body and selectively connecting the pilot valve chamber and the outflow passage;
a pressure equalizing passage that communicates the main valve chamber and the pilot valve chamber;
a pilot valve seat formed at an end of the pilot passage on the pilot valve chamber side;
a pilot valve body that moves back and forth relative to the pilot valve seat to open and close the pilot passage;
a moving body that holds the pilot valve body and moves together with the pilot valve body, and transmits a pressing force to the pilot valve body to press the pilot valve body against the pilot valve seat to close the pilot passage;
an electric drive device that drives the pilot valve body via the moving body,
a point contact portion where a convex curved surface and a flat surface or where two convex curved surfaces contact each other is formed between the pilot valve body and the moving body,
the pressing force is transmitted from the moving body to the pilot valve element via the point contact portion. a valve body having a valve chamber therein;
a first flow path serving as one of an inflow path through which a refrigerant flows into the valve chamber and an outflow path through which a refrigerant flows out of the valve chamber;
a second flow path which is the other of an inflow path for introducing a refrigerant into the valve chamber and an outflow path for discharging a refrigerant from the valve chamber;
a valve port having a valve seat and disposed between the first flow path or the second flow path and the valve chest so as to open into the valve chest;
a valve element that moves back and forth relative to the valve seat between a valve closing position where the valve element is pressed against the valve seat to close the valve port by receiving a pressing force in a valve closing direction and a valve opening position where the valve element is separated from the valve seat to open the valve port;
a moving body that holds the valve body and moves together with the valve body;
a valve receiving member interposed between the moving body and the valve body to transmit the pressing force to the valve body;
and an electric drive device that drives the valve body via the moving body,
a point contact portion where a convex curved surface and a flat surface or where two convex curved surfaces contact each other is formed between the valve body and the valve receiving member,
the pressing force is transmitted from the valve receiving member to the valve body via the point contact portion. The valve receiving member is
7. The electrically driven valve according to claim 6, wherein the plate-shaped member has a flat surface that contacts the movable body and a convex curved surface that contacts the valve body. The valve receiving member is
7. The electrically driven valve according to claim 6, wherein the plate-shaped member has a central portion recessed toward the valve body to form a convex curved surface portion protruding toward the valve body. The electrically driven valve according to claim 6 , wherein the valve receiving member is a spherical member. a valve body having a valve chamber therein;
a first flow path serving as one of an inflow path through which a refrigerant flows into the valve chamber and an outflow path through which a refrigerant flows out of the valve chamber;
a second flow path which is the other of an inflow path for introducing a refrigerant into the valve chamber and an outflow path for discharging a refrigerant from the valve chamber;
a valve port having a valve seat and disposed between the first flow path or the second flow path and the valve chest so as to open into the valve chest;
a valve element that moves back and forth relative to the valve seat between a valve closing position where the valve element is pressed against the valve seat to close the valve port by receiving a pressing force in a valve closing direction and a valve opening position where the valve element is separated from the valve seat to open the valve port;
a moving body that holds the valve body and moves together with the valve body;
and an electric drive device that drives the valve body via the moving body,
a point contact portion where the convex curved surfaces are in contact with each other is formed between the valve body and the moving body,
the pressing force is transmitted from the moving body to the valve body via the point contact portion.

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