JP7253786B2 - valve device - Google Patents

Description

The present invention relates to valve devices.

Mechanical constant pressure valves, expansion valves, and the like are known as valve devices for controlling the flow rate of refrigerant in air conditioners. For example, in Patent Document 1, when the driving force of a power element increases, a spherical valve body is opened via an operating rod. An expansion valve is disclosed that closes the body.

JP 2019-011886 A

Furthermore, in the expansion valve disclosed in Patent Document 1, a vibration isolation spring is provided to dampen the vibration of the operating rod in order to suppress abnormal noise caused by the vibration of the operating rod.

However, it has been confirmed that even if the vibration of the operating rod is suppressed by the anti-vibration spring, abnormal noise may occur. Analysis by the present inventors revealed that vibration of the valve body was the cause of the noise. As for the mechanism of noise generation, since the end of the actuating rod that drives the sphere as the valve body is flat, the surface of the sphere and the end of the actuating rod come into point contact. It is presumed that the valve body oscillates due to disturbance when the refrigerant passes through the valve, causing vibration.

In particular, in an expansion valve of the type described in Patent Document 1, in which a coil spring disposed in a valve chamber biases a valve disc in the valve closing direction, the coil spring is vibrated by the flow of refrigerant, causing the valve disc to vibrate. It was also found to increase vibration.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an improved valve device capable of suppressing abnormal noise at a low cost.

In order to achieve the above object, the valve device according to the present invention comprises:
a case internally provided with a pressure detection chamber into which a refrigerant enters and a pressure actuation chamber in which a gas is sealed;
a flexible diaphragm separating the pressure detection chamber and the pressure actuation chamber in the case;
a moving body that moves in a valve opening direction according to the displacement of the diaphragm;
a valve body having a valve chamber forming a valve seat and joined to the case;
a valve body arranged in the valve chamber so as to be seatable on the valve seat and in contact with the moving body;
The valve body is formed of a circular metal plate material, and when the movable body applies a force in the valve opening direction, the valve body is elastically deformed toward the valve chamber, thereby being separated from the valve seat. It is characterized in that, when no force is applied in the valve opening direction from the moving body, it recovers from the deformation due to its own elastic force and is seated on the valve seat.

ADVANTAGE OF THE INVENTION By this invention, the improved valve apparatus which can suppress abnormal noise can be provided, although it is low-cost.

FIG. 1 is a schematic cross-sectional view schematically showing an example in which the expansion valve of this embodiment is applied to a refrigerant circulation system. FIG. 2 is a perspective view showing an enlarged cross-section in the vicinity of the lower end of the operating rod and the valve body. FIG. 3 is a perspective view of the valve body. FIG. 4 is a perspective view showing a ring spring. FIG. 5 is an enlarged cross-sectional view of the vicinity of the lower end of the operating rod and the valve body. FIG. 6 is a perspective view showing an enlarged cross section in the vicinity of the lower end of the operating rod, the valve body, and the holding plate. FIG. 7 is a perspective view of the valve body and holding plate.

Hereinafter, embodiments according to the present invention will be described with reference to the drawings.

(definition of direction)
In this specification, the side from the valve body toward the diaphragm is defined as "upper", and the side from the diaphragm toward the valve body is defined as "downward".

An outline of an expansion valve 1, which is a valve device according to an embodiment of the present invention, will be described with reference to FIG. FIG. 1 is a schematic cross-sectional view schematically showing an example in which the expansion valve 1 of this embodiment is applied to a refrigerant circulation system 100. As shown in FIG. In this example, expansion valve 1 is fluidly connected to compressor 101 , condenser 102 and evaporator 103 .

The expansion valve 1 includes a valve body 2 having a valve chamber VS, a valve body 3, an operating rod 5, a ring spring 6, and a power element 8. Let L be the axis of the expansion valve 1 . The actuating rod 5 constitutes a moving body.

The valve body 2 includes a first flow path 21 and a second flow path 22 in addition to the valve chamber VS. The first flow path 21 is a supply-side flow path, and refrigerant (also referred to as fluid) is supplied to the valve chamber VS through the supply-side flow path. The second flow path 22 is a discharge side flow path, and the fluid in the valve chamber VS is discharged to the outside of the expansion valve through the communication hole 27 through which the lower end of the operating rod 5 is inserted and the discharge side flow path. The first flow path 21 and the valve chamber VS are communicated with each other by a connection path 21a having a diameter smaller than that of the first flow path 21 . A plug 43 seals the lower end of the valve chamber VS.

FIG. 2 is a perspective view showing an enlarged cross section near the lower end of the operating rod 5 and the valve body 3. As shown in FIG. In the valve body 2, an annular concave portion 27a is formed by annularly recessing the periphery of the lower end of the communication hole 27 at the upper end of the valve chamber VS. By forming the annular recess 27a, the lower edge of the communication hole 27 protrudes annularly downward to form a projecting portion 27b. The cross section of the projecting portion 27b has a semicircular shape on the lower end side, and the lowermost end constitutes the valve seat 20. As shown in FIG.

The lower end of the operating rod 5 forms a flat surface 5a, and the flat surface 5a contacts the upper surface of the valve body 3. As shown in FIG.

FIG. 3 is a perspective view of the valve body 3. FIG. For example, the valve element 3 as a diaphragm can be formed by plastically working a circular SUS plate material having a thickness of about 1 mm by press forming so that the center protrudes. The valve body 3 includes a central circular portion 3a having a flat upper surface, a peripheral annular portion 3b shifted downward with respect to the circular portion 3a, and connecting the outer periphery of the circular portion 3a and the inner periphery of the peripheral annular portion 3b. A plurality of (six in this case) leg portions 3c extending radially obliquely downward are arranged in a row. An opening 3d surrounded by the adjacent leg portion 3c, the circular portion 3a, and the surrounding annular portion 3b penetrates the valve body 3 in the plate thickness direction, and the opening 3d forms a coolant flow path. The circular portion 3a constitutes a contact portion, and the leg portion 3c constitutes a deformation portion.

In the valve body 3, the peripheral annular portion 3b may be removed and the radially outer ends of the leg portions 3c may be free ends. In such a case, the radially outer end of the leg portion 3c is attached to the valve chamber VS by caulking. Moreover, it is preferable that the valve body 3 has a rotationally symmetrical shape.

A process of assembling the valve body 3 to the valve main body 2 will be described. The inner diameter of the valve chamber VS is slightly smaller than the outer diameter of the valve body 3 in the free state. Further, in FIG. 2, a circumferential groove 2c is formed on the inner circumference near the upper end of the valve chamber VS.

When the valve body 3 is pushed into the valve chamber VS from below the valve body 2 before a plug 43 (described later) for sealing the lower end of the valve chamber VS is assembled, the valve body 3 shrinks due to elastic deformation. Diameter. Further, when the valve body 3 is pushed upward, the peripheral annular portion 3b fits into the peripheral groove 2c and recovers from the deformation, and the circular portion 3a contacts the valve seat 20 of the valve body 2. As shown in FIG. Although the valve body 3 can be attached to the valve main body 2 even in such a state, caulking is used in this embodiment in order to secure it more firmly.

More specifically, a bump is formed below the circumferential groove 2c, and a tool (not shown) inserted into the valve chamber VS is used to pressurize the bump while holding the valve body 3. Plastic deformation is caused to form the crimped portion CK. As a result, the crimped portion CK presses the surrounding annular portion 3b, and as shown in FIG. 2, the valve body 3 can be fixed to the upper portion of the valve chamber VS. In the attached state, the valve body 3 is preloaded in the plate thickness direction by the caulked portion CK, whereby the leg portion 3c is elastically deformed, and the state of pressing the circular portion 3a against the valve seat 20 is maintained. After that, the operating rod 5 is inserted from above to abut against the circular portion 3a of the valve body 3, and the plug 43 seals the lower end of the valve chamber VS.

Next, the power element 8 will be described with reference to FIG. The power element 8 is attached to a recess 2 a provided at the top of the valve body 2 . The recess 2a communicates with the return flow path 23 in the valve body 2 through which the refrigerant from the evaporator 103 passes through the communication path 2b. An operating rod 5 passes through the communication passage 2b. A female thread is formed on the inner periphery of the recess 2a.

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

The upper lid member 82 has a central conical portion 82a and an annular flange portion 82b extending from the lower end of the conical portion 82a to the outer circumference. An opening 82c is formed at the top of the conical portion 82a and can be sealed with a plug 81. As shown in FIG.

The diaphragm 83 is made of a thin plate material in which a plurality of concentric concave and convex shapes are formed. The stopper member 84 has a fitting hole 84a at the center of the lower end.

The receiving member 86 includes a flange portion 86a having substantially the same outer diameter as the flange portion 82b of the upper lid member 82, a stepped portion 86c having an annular support surface 86b substantially perpendicular to the axis L, and a hollow cylindrical portion 86d. have. A male thread is formed on the outer circumference of the hollow cylindrical portion 86d.

A procedure for assembling the power element 8 will be described. The upper cover member 82, the diaphragm 83, the stopper member 84, and the receiving member 86 are arranged so as to have the positional relationship shown in FIG.

Furthermore, in a state in which the outer peripheral portions of the flange portion 82b of the upper lid member 82, the diaphragm 83, and the flange portion 86a of the receiving member 86 are overlapped, the outer peripheral portions are circumferentially welded by TIG welding, laser welding, plasma welding, or the like. and unify. A case is composed of the upper cover member 82 and the receiving member 86 .

Subsequently, after the working gas is sealed from the opening 82c formed in the upper lid member 82 into the space (pressure actuation chamber PO) surrounded by the upper lid member 82 and the diaphragm 83, the opening 82c is sealed with the plug 81, Further, the plug 81 is fixed to the upper cover member 82 by projection welding or the like.

At this time, due to the working gas sealed in the pressure actuation chamber PO, the diaphragm 83 receives pressure in the form of protruding toward the receiving member 86, so that the space surrounded by the diaphragm 83 and the receiving member 86 (pressure detection chamber PD) It is supported in contact with the upper surface of the arranged stopper member 84 .

When assembling the power element 8, the male thread of the hollow cylindrical portion 86d of the receiving member 86 is engaged with the female thread of the recess 2a of the valve body 2 while the upper end of the operating rod 5 is fitted into the fitting hole 84a of the stopper member 84. The power element 8 is fixed to the valve body 2 by screwing. In this state, the pressure detection chamber PD of the power element 8 communicates with the return channel 23, ie, has the same internal pressure. The receiving member 86 and the upper surface of the valve body 2 are sealed with a packing PK.

Next, the ring spring 6 will be explained. The ring spring 6 is installed in a cylindrical recess 26 of the valve body 2 in FIG. FIG. 4 is a perspective view showing the ring spring 6. FIG.

The ring spring 6 is constructed by bending a plate-like member into a cylindrical shape as shown in FIG. 4 and bending a first elastic piece 61, a second elastic piece 62 and a third elastic piece 63 inward. be done.

The first elastic piece 61, the second elastic piece 62 and the third elastic piece 63 are cut and bent inward. The second convex contact portion 62a and the third convex contact portion 63a are designed so as to divide the circumference into three equal parts. In a plane perpendicular to the axis L (FIG. 1), an inscribed contact connecting the tops of the first convex contact portion 61a, the second convex contact portion 62a, and the third convex contact portion 63a is provided. The diameter of the circle is smaller than the outer diameter of the operating rod 5 . As a result, a predetermined pressing force is applied to the outer circumference of the operating rod 5 from the first convex contact portion 61a, the second convex contact portion 62a, and the third convex contact portion 63a. becomes.

(Operation of expansion valve)
An operation example of the expansion valve 1 will be described with reference to FIG. The refrigerant pressurized by the compressor 101 is liquefied by the condenser 102 and sent to the expansion valve 1 . The refrigerant adiabatically expanded by the expansion valve 1 is sent to the evaporator 103, where it exchanges heat with the air flowing around the evaporator. The refrigerant returning from the evaporator 103 is returned to the compressor 101 side through the expansion valve 1 (more specifically, the return passage 23).

The expansion valve 1 is supplied with high-pressure refrigerant from a condenser 102 . More specifically, the high pressure refrigerant from the condenser 102 is supplied to the valve chamber VS through the first flow path 21 .

In FIG. 1, inside the power element 8, a pressure actuation chamber PO and a pressure detection chamber PD separated by a diaphragm 83 are provided. Therefore, when the working gas in the pressure working chamber PO is liquefied, the working rod 5 is displaced upward (referred to as the valve closing direction), and when the liquefied working gas is vaporized, the working rod 5 is moved downward. It is displaced in the (valve opening direction).

When the operating rod 5 is displaced upward, the circular portion 3a of the valve body 3 is kept seated on the valve seat 20 by the elastic force of the leg portion 3c, as indicated by the solid line in FIG. Refrigerant in the valve chamber VS enters the annular recess 27a through the opening 3d (FIG. 3), but cannot enter the communication hole 27 because the circular portion 3a is seated on the valve seat 20. That is, when the valve body 3 is seated on the valve seat 20, the first flow path 21 and the second flow path 22 are not communicated with each other.

On the other hand, when the operating rod 5 moves downward, the circular portion 3a of the valve body 3 is pressed downward toward the inside of the valve chamber VS, and the leg portion 3c is elastically deformed as indicated by the dotted line in FIG. As a result, the circular portion 3a is separated from the valve seat 20, so that the refrigerant flows from the annular concave portion 27a toward the communication hole 27 as indicated by the arrow. That is, when the valve body 3 is separated from the valve seat 20, the first flow path 21 and the second flow path 22 are in communication.

Thereby, the refrigerant supplied to the valve chamber VS is sent out to the evaporator 103 through the communication hole 27 and the second flow path 22 . Switching of the valve is effected by an actuating rod 5 connected to a power element 8 .

A pressure detection chamber PD of the power element 8 communicates with the return flow path 23 . Therefore, the phase (gas phase, liquid phase, etc.) of the working gas in the pressure working chamber PO changes according to the temperature and pressure of the refrigerant flowing through the return passage 23, and the working rod 5 is driven. In other words, in the expansion valve 1 shown in FIG. 1, the amount of refrigerant supplied from the expansion valve 1 toward the evaporator 103 is automatically adjusted according to the temperature and pressure of the refrigerant returning from the evaporator 103 to the expansion valve 1. adjusted.

According to this embodiment, the refrigerant flows around the valve body 3 when the valve is opened. and its vibration can be effectively suppressed. Furthermore, since the valve body 3 as a diaphragm itself has an elastic force, it is not necessary to provide a coil spring for urging the valve body 3 inside the valve chamber VS. As a result, it is possible to eliminate the vibration caused by the collision of the refrigerant flow when the coil spring is provided. However, even if the operating rod 5 moves downward with the maximum stroke, the valve body 3 does not reverse. Further, it is preferable that the gap between the valve seat 20 and the valve body 3 is linear with respect to the stroke of the operating rod 5 .

In this embodiment, no coil spring is accommodated in the valve chamber VS, but by ensuring a large-capacity valve chamber VS, a muffler effect can be exhibited and noise can be reduced when refrigerant passes. Furthermore, by arranging a filter, a strainer, etc. in the valve chamber VS, noise can be reduced and foreign matter mixed in the refrigerant can be captured. Filters, strainers, etc. can be replaced or cleaned by removing the plug 43 .

(Modification)
Next, a modified example of this embodiment will be described with reference to FIGS. FIG. 6 is a perspective view showing an enlarged cross section near the lower end of the operating rod 5, the valve body 3A, and the holding plate 9. As shown in FIG. 7 is a perspective view of the valve body 3A and the holding plate 9. FIG. In this modification, the valve body 3A is attached to the valve chamber VS of the valve main body 2A via the holding plate 9. As shown in FIG. Since other configurations are the same as those of the above-described embodiment, the same reference numerals are given and redundant explanations are omitted.

The valve body 3A has a shape in which a conical tapered portion 3e is continuously provided around a circular portion 3a, and constitutes a diaphragm. The valve body 3A can be formed, for example, by plastic working a SUS plate material having a thickness of about 1 mm by press forming so that the center protrudes. It should be noted that an opening can be provided in the tapered portion 3e as in the above-described embodiment. The tapered portion 3e constitutes a deformation portion.

The holding plate 9 is made of aluminum, for example, and includes an inner annular portion 9a, an outer annular portion 9b disposed therearound, and three beam portions 9c connecting the inner annular portion 9a and the outer annular portion 9b. have Between the adjacent beam portions 9c is an arc-shaped slit 9d which is an opening that communicates the upper and lower surfaces. The arcuate slit 9d constitutes a coolant flow path.

The radially outer upper surface of each beam portion 9c is at the same level as the upper surface of the outer annular portion 9b, and the radially inner upper surface is at the same level as the upper surface of the inner annular portion 9a. On the other hand, since the upper surface level of the inner annular portion 9a is lower than the upper surface level of the outer annular portion 9b, each beam portion 9c is provided with a stepped surface 9e in the middle to connect the upper surfaces on both sides. The stepped surface 9e is a part of a cylindrical surface whose axis is the axis L of the holding plate, and the inner diameter of the cylindrical surface substantially matches the outer diameter of the valve body 3A.

A male thread 9f is formed on the outer circumference of the outer annular portion 9b. On the other hand, in FIG. 6, a female screw SC is formed on the upper inner periphery of the valve chamber VS.

At the time of assembly, the outer periphery of the valve body 3A is fitted to the stepped surface 9e of the holding plate 9, the male screw 9f is screwed into the female screw SC of the valve chamber VS, and the three screws protruding from a tool (not shown) are threaded. The pawl is engaged with the arcuate slit 9d. By rotating the tool about the axis L from this state, the holding plate 9 moves upward while rotating with respect to the valve chamber VS, and the circular portion 3a of the valve body 3A comes into contact with the valve seat 20. As shown in FIG. Due to the reaction force at that time, the outer circumference of the tapered portion 3e collides with the stepped surface 9e and is deformed, thereby exerting an elastic force (FIG. 6). By adjusting the amount of screwing of the holding plate 9 into the valve chamber VS, the preload acting between the circular portion 3a and the valve seat 20 can be adjusted.

When the operating rod 5 is displaced upward, the state where the circular portion 3a is seated on the valve seat 20 is maintained by the elastic force of the tapered portion 3e of the valve body 3A. Refrigerant in the valve chamber VS passes through the arc-shaped slit 9d of the holding plate 9 and the outside of the tapered portion 3e to reach the annular recess 27a, as indicated by the arrow in FIG. Since it is seated on 20, it cannot enter the communication hole 27.例文帳に追加

On the other hand, when the actuating rod 5 moves downward, the circular portion 3a of the valve body 3A is pressed downward, thereby separating the circular portion 3a from the valve seat 20. Refrigerant will flow through it (see FIG. 5).

In the modified example described above, an example is shown in which the holding plate 9 is screwed to the valve chamber VS, but it can also be fixed by caulking or press-fitting, for example. Moreover, the present invention is applicable not only to expansion valves but also to various valve devices such as constant pressure valves.

It should be noted that the present invention is not limited to the above-described embodiments. Variations of any components of the above-described embodiments are possible, and additions or omissions of any components of the above-described embodiments are possible within the scope of the invention.

Reference Signs List 1: Expansion valves 2, 2A: Valve bodies 3, 3A: Valve body 5: Operating rod 8: Power element 9: Holding plate 100: Refrigerant circulation system 101: Compressor 102: Condenser 103: Evaporator

Claims (6)

a case internally provided with a pressure detection chamber into which a refrigerant enters and a pressure actuation chamber in which a gas is sealed;
a flexible diaphragm separating the pressure detection chamber and the pressure actuation chamber in the case;
a moving body that moves in a valve opening direction according to the displacement of the diaphragm;
a valve body having a valve chamber forming a valve seat and joined to the case;
a valve body arranged in the valve chamber so as to be seatable on the valve seat and in contact with the moving body;
The valve body is formed of a circular metal plate material, and when the movable body applies a force in the valve opening direction, the valve body is elastically deformed toward the valve chamber, thereby being separated from the valve seat. When no force is applied in the valve opening direction from the moving body, the valve recovers from deformation due to its own elastic force and sits on the valve seat.
A valve device characterized by: The valve body is a diaphragm that is plastically processed so that the center protrudes,
2. The valve device according to claim 1, characterized in that: The diaphragm of the valve body has a flow path that penetrates in the plate thickness direction and allows the refrigerant to pass through,
3. The valve device according to claim 2, characterized in that: a retaining plate that attaches the diaphragm of the valve body to the valve body;
3. The valve device according to claim 2, characterized in that: The holding plate has a flow path that penetrates in the plate thickness direction and allows the coolant to pass through,
5. The valve device according to claim 4, characterized in that: The valve body has a central abutment portion that abuts on the moving body and a deformation portion that extends radially outward from the abutment portion. When a force in a valve opening direction is applied from the moving body to the contact portion, the deformation portion deforms to generate an elastic force.
2. The valve device according to claim 1, characterized in that:

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