JPH07151242A - Control valve - Google Patents

Abstract

PURPOSE:To suppress the temperature variation of the fluid in the fluid passage of a valve casing and shift a valve rod always smoothly. CONSTITUTION:A control valve is equipped with a valve casing A, valve operating part B, valve rod supporting member 3, valve rod 4 and a valve element. The valve rod supporting member 3 is equipped with an upper side pipe 14C whose upper end is fixed at the valve operating part B and the lower end is separated from the valve casing A, lower side pipe 14A which is arranged inside the pipe 14C and the lower end is fixed with the valve casing A and the upper end is separated from the valve operating part B, and a pipe 14B which is arranged in the intermediate part of both the pipes 14C and 14A and whose upper and lower ends are separated from the valve operating part B and the valve casing A. The upper end part of the pipe 14B in the intermediate part and the upper end part of the lower side pipe 14A, and further the lower end part and the lower end part of the upper side pipe 14C are connected by the connecting rings 15 and 16, respectively. On a connecting ring 16 on the lower side, a plurality of tapped holes which penetrate in the radial direction are formed in the circumferential direction, keeping each interval. tn oscillation preventing member 18 consisting of a male member is screwed from outside into each tapped hole, and the top end is brought into contact with the lower side pipe 14A.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control valve, and more specifically to a valve body having a fluid passage and a valve seat, a valve operating portion, an upper end fixed to the valve operating portion and a lower end fixed to the valve body. Mounted on the lower end of the valve stem, the valve stem supporting member, the valve stem that penetrates the valve stem supporting member, the upper end of which is connected to the valve operating part, and the lower end of which is inserted into the valve body. The valve body moves up and down as the valve rod moves up and down, and when the valve body moves downward, it comes into contact with and seats on the valve seat, closing the fluid passage. A control valve adapted to move upward to open the passage of fluid away from the valve seat.

In this specification, the upper and lower parts are shown in FIG.
Refer to FIG. 2 and FIG.

[0003]

2. Description of the Related Art Conventionally, in this type of control valve, the valve rod support member is formed of one tubular body.

However, in the conventional control valve, when a low temperature fluid or a high temperature fluid is caused to flow in the fluid passage of the valve body, heat flows in between the valve operating portion and the fluid through the valve rod support member.
There was a problem that the temperature of the fluid changed due to the outflow.

Therefore, in order to solve such a problem, the present applicant has previously proposed that the valve body having a fluid passage and a valve seat, the valve operating portion, and the upper end being fixed to the valve operating portion. A valve rod support member having a lower end fixed to the valve body,
A valve rod having an upper end connected to the valve operating portion and a lower end entering the valve body through the valve rod support member; and a valve element attached to the lower end of the valve rod, When the valve rod moves up and down, the valve element moves up and down, and when the valve element moves downward, it contacts and seats on the valve seat, closing the fluid passage, and when the valve element moves upward, this causes the valve to move. In a control valve configured to open a fluid passage away from a seat, a valve rod support member has an upper tubular body whose upper end is fixed to a valve operating portion and whose lower end is separated from a valve body, and whose lower end is a valve body. And a lower tubular body whose upper end is separated from the valve operating portion, and the two tubular bodies are fitted together at intervals, with the lower end of the upper tubular body and the upper end of the lower tubular body. Proposes a control valve that is connected by a connecting member Was (see Japanese Patent Application No. Hei 5-107007).

However, it has been found that such a control valve has the following problems. That is, the free ends of the upper tubular body and the lower tubular body, which are located outside, swing, and as a result, the connecting member comes into contact with one of the tubular bodies to shorten the heat transfer path and increase the heat transfer amount. As a result, the temperature of the fluid flowing in the fluid passage of the valve box easily changes.
Further, when the above-described touch occurs, the core of the valve rod support member and the valve rod are displaced, and as a result, the valve rod does not move smoothly. Moreover, in order to prevent the occurrence of the above shake,
It is sufficient to increase the wall thickness of the upper tubular body and the lower tubular body that are located on the outer side, but in this case too, the heat transfer amount increases and the temperature of the fluid flowing in the fluid passage of the valve box changes. Easier to do.

An object of the present invention is to provide a control valve that solves the above problems.

[0008]

A control valve according to the present invention includes a valve body having a fluid passage and a valve seat, a valve operating portion, an upper end fixed to the valve operating portion and a lower end fixed to the valve body. Valve stem supporting member, a valve stem penetrating the valve stem supporting member, the upper end portion of which is connected to the valve operating portion and the lower end portion of which enters the valve body, and the valve attached to the lower end of the valve stem. The valve body moves up and down when the valve rod moves up and down, and when the valve body moves downward, it contacts and seats the valve seat to close the fluid passage, and the valve body moves upward. In a control valve in which the valve rod support member is configured to open a fluid passage away from the valve seat by moving the valve rod support member to an upper tubular shape whose upper end is fixed to the valve operating portion and whose lower end is separated from the valve body. Body and the lower end is fixed to the valve body A lower tubular body having an upper end spaced apart from the valve operating portion, the tubular bodies are fitted to each other with a space therebetween, and the lower end of the upper tubular body and the upper end of the lower tubular body are connected by a connecting member. And a shake prevention member for preventing shake of the free end of the tubular body located outside.

[0009]

The valve rod support member has an upper tubular body whose upper end is fixed to the valve operating part and whose lower end is separated from the valve body, and a lower side whose lower end is fixed to the valve body and whose upper end is separated from the valve operating part. A tubular body, the two tubular bodies are fitted to each other at an interval, and the lower end portion of the upper tubular body and the upper end portion of the lower tubular body are connected by a connecting member. The heat transfer path is longer than that of the conventional valve stem support member. Therefore, the amount of heat transfer between the fluid passing through the valve rod support member and the valve operating portion is reduced.

Further, when the anti-vibration member for preventing the free end of the tubular body located outside is provided, the free end of the upper tubular body or the lower tubular body located outside is prevented from vibrating. To be done.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the overall structure of the control valve, and FIGS. 2 to 4 show the details of the main parts thereof.

In FIG. 1, the control valve is a valve body (A).
A valve operating part (B) and a valve rod support member whose upper end is fixed to the valve operating part (B) and whose lower end is fixed to the valve body (A).
(3) and a valve rod (4) that penetrates the valve rod support member (3) and has its upper end connected to the valve operating part (B) and its lower end entering the valve body (A). , And a valve body (5) attached to the lower end of the valve rod (4).

The valve body (A) comprises a valve box (1) and a valve lid (2) fixed to the valve box (1). The valve box (1) is formed with a fluid passage (6) from one side surface to the other side surface, and the fluid circulation pipes (P) are connected to both side surfaces of the valve box (1). The fluid flow pipe (P) is covered with a heat insulating cover (C). Also,
The valve box (1) is integrally formed with a cylindrical part (1a) that projects obliquely upward, and the cylindrical part (1a) extends in the length direction from its upper end surface and has its lower end part in the fluid passage (6). Facing valve rod hole (7)
Are formed. From the top wall to the bottom wall of the valve box (1),
A valve seat (8) is formed facing upward at an angle.

A valve lid is provided on the upper end of the cylindrical portion (1a) of the valve box (1).
(2) is fixed. The valve lid (2) has a disc-shaped portion (9) that closes the upper end opening of the valve stem hole (7), and the upper end is closed and the lower end is open.
A cylindrical part (1) that is fixed to the upper surface of (9) and extends diagonally upward.
It consists of 1). At the center of the disc-shaped part (9), the valve rod guide hole (1
2) is formed. A through hole (13) is formed in the central portion of the upper end closing wall of the cylindrical portion (11).

As shown in FIG. 2, the valve rod support member (3) is composed of a metal triple tube (14). The lower end of the innermost pipe (14A) (lower tubular body) of the three pipes (14A) (14B) (14C) forming the triple pipe (14) is the cylindrical portion of the valve lid (2) ( It is inserted into the through hole (13) of the upper end closing wall of (11) and fixed by welding. The upper end of this pipe (14A) is separated from the valve operating part (B). The upper end of the outermost pipe (14C) (upper tubular body) of all the pipes (14A) to (14C) forming the triple pipe (14) is the valve operating part.
It is fixed to (B). The lower end of this tube (14C) is the valve body
Separated from (A). All tubes (1
4A) to (14C), the upper and lower ends of the central pipe (14B) are separated from the valve operating part (B) and the valve body (A), respectively.
The upper end of this pipe (14B) is connected to the upper end of the innermost pipe (14A) via the connecting ring (15), and the lower end is the connecting ring.
It is connected to the lower end of the outermost pipe (14C) via (16). The two pipes (14A) (14B) and the connecting ring (15), and the two pipes (14B) (14C) and the connecting ring (16) are welded, respectively. A connecting member that connects the upper end of the innermost pipe (14A) and the lower end of the outermost pipe (14C) by the connecting ring (15), the central pipe (14B) and the connecting ring (16). (17)
Is configured.

As shown in FIG. 3, the lower connecting ring (16)
In addition, a plurality of, for example, three screw holes (10) penetrating this in the radial direction are formed at intervals in the circumferential direction. The number of screw holes (10) is not limited to three. Each screw hole (1
(0), a synthetic resin shake prevention member (18) consisting of a male screw member
Is screwed from the outside, and the tip is the innermost tube (14A)
Is abutted against. The shake prevention member is not limited to the synthetic resin.

The peripheries of the valve lid (2) and the valve stem support member (3) are covered with a cylindrical portion (C1) provided on the heat insulating cover (C).

The valve rod (4) includes an upper rod member (20) made of metal,
It is composed of a lower rod-shaped member (21) made of fiber reinforced plastic. The upper end of the upper rod-shaped member (20) is connected to the valve operating part (B) and can be moved up and down by the valve operating part (B). As shown in FIG. 2, a retaining ring (22) is fixed to a portion of the lower rod-shaped member (21) located inside the cylindrical portion (11) of the valve lid (2), which is more than the retaining ring (22). In the lower part, a spring receiver (23) is vertically movably fitted around the lower rod member (21). A compression coil spring (24) is arranged around the lower rod member (21) between the upper surface of the disc-shaped portion (9) of the valve lid (2) and the spring receiver (23).

In the lower rod-shaped member (21), the large diameter portion (2) is formed in the portion of the cylindrical portion (1a) of the valve box (1) located in the valve rod hole (7).
1a) has been formed. The large diameter part (21
Holes formed in the upper surface of the valve body (5) in the lower part than a)
It is fitted in (5a) and fixed to the valve body (5) by a pin (25). The lower rod-shaped member (21) has a lower end position where the valve body (5) contacts and seats the valve seat (8) and an upper end position where the large diameter part (21a) abuts the disc-shaped part (9). Between them, the valve body (5) is fully opened at its upper end position.

A cylindrical portion (26) projecting obliquely upward is integrally formed on the peripheral edge of the valve body (5). Cylindrical part (26)
A shallow annular groove (27) is formed on the outer peripheral surface of the
A plastic cylindrical guide (28) made of a synthetic resin, for example, a fluororesin, which slides on the inner peripheral surface of the cylindrical portion (11) of the valve lid (2) is fitted therein. Lower bar
The ring (29) is fixed to the upper end of the part of the (21) projecting upward from the hole (5a) in the part below the large diameter part (21a), and the ring (29) and the valve lid (2) are Between the disc-shaped portion (9) and the upper and lower ends of a bellows (30) that seals the space between them are closely fixed.

When the upper rod-shaped member (20) of the valve rod (4) is moved downward by the valve operating section (B), the lower rod-shaped member (21) and the valve body (5) are moved downward, and the valve body ( As (5) moves downwards, it contacts and seats the valve seat (8) and the fluid passage (6)
Close. When the valve body (5) is fully closed, the lower rod-shaped member
The upper end surface of (21) and the lower end surface of the upper rod-shaped member (20) are in contact with each other, but the action of the plastic lower rod-shaped member (21) causes the fluid passage (6 The amount of heat transfer between the fluid in () and the valve operating part (B) decreases. Moreover, the valve rod support member (3) is made of a metal triple pipe (14), and the innermost pipe (1)
The lower end of 4A) is fixed to the valve lid (2), the upper end is separated from the valve operating part (B), and the upper end of the outermost pipe (14C) is fixed to the valve operating part (B). The bottom end is the valve body (A)
Since the upper end of the innermost pipe (14A) and the lower end of the outermost pipe (14C) are connected by the connecting member (17), heat of the valve rod support member (3) The transfer path becomes long, and the amount of heat transfer between the fluid in the fluid passageway (6) passing through the valve rod support member (3) and the valve operating section (B) is reduced. further,
Since the shake prevention member (18) prevents the lower end of the outermost pipe (14C) from swinging, the lower end of the central pipe (14B) becomes the lower end of the innermost pipe (14A). Contact is prevented and, as a result, short heat transfer paths are prevented.

When the upper rod-shaped member (20) of the valve rod (4) is moved upward by the valve operating section (B), the lower rod-shaped member (21) and the valve body (5) are elastically compressed by the compression coil spring (24). The valve seat (5) moves upward due to the force, which causes the valve seat (5) to move upward.
Fluid passage (6) opens away from (8). Lower bar (21)
Moves upward and the upper end of the large diameter part (21a) is a disc-shaped member.
When the lower rod-shaped member (21) reaches the upper end position by contacting the (9), the lower rod-shaped member (21) is stopped at this position. After that, the valve operating section (B) moves the upper rod-shaped member (20) by a distance larger than the moving distance from the lower end position to the upper end position of the lower rod-shaped member (21), and the lower rod-shaped member (21) and the upper rod-shaped member (21).
(20) is separated (see Fig. 4). Therefore, when the control valve is fully opened, the fluid flowing through the fluid passage (6) and the valve operating part
Heat transfer between the (B) and the valve stem (4) is prevented.
Moreover, even in this fully open state, heat transfer between the fluid in the fluid passageway (6) and the valve operating section (B) through the valve rod support member (3) is the same as in the fully closed state. The amount decreases.

In the above embodiment, since at least a part of the entire length of the valve rod is made of plastic,
The heat insulating property of the part formed of plastic becomes excellent, and the amount of heat transfer between the fluid passing through the valve rod and the valve operating part is reduced. Therefore, the effect of preventing the temperature change of the low temperature fluid and the high temperature fluid flowing in the fluid passage of the valve body is improved.

In the above embodiment, the pipe (14C) whose upper end of the valve rod support member (3) is fixed to the valve operating portion (B) and whose lower end is separated from the valve body (A) is located at the outermost side. It is arranged and equipped with a shake prevention member (18) so as to prevent shake of the lower end of this pipe (14C) .On the contrary, the lower end is fixed to the valve body (A) and the upper end is fixed. The pipe (14A) separated from the valve operating part (B) is arranged on the outermost side, and a shake prevention member (18) may be provided so as to prevent the upper end of the pipe (14A) from shaking. .

[0026]

According to the control valve of the present invention, as described above, the amount of heat transfer between the fluid passing through the valve rod support member and the valve operating portion is reduced, so that the control valve in the fluid passage of the valve body is reduced. Even when a low-temperature fluid or a high-temperature fluid is passed through, the temperature change of this fluid is prevented. Moreover, since the heat transfer path in the valve rod support member can be made longer than that of the conventional valve rod support member without increasing the length of the valve rod support member, the entire control valve can be downsized.

Further, since the free end of the upper tubular body and the lower tubular body located outside is prevented from swinging,
An increase in the amount of heat transfer due to the connection member coming into contact with one of the tubular bodies and the heat transfer path being shortened is prevented. Moreover, it is possible to prevent an increase in the amount of heat transfer due to increasing the wall thickness of the upper tubular body and the lower tubular body that are located outside. Therefore, this also suppresses the temperature change of the fluid flowing in the fluid passage of the valve body. Further, the misalignment of the core between the valve stem support member and the valve stem is prevented, and as a result, the valve stem always moves smoothly.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an overall configuration when a valve body of a control valve according to the present invention is in a fully closed state.

FIG. 2 is a partially enlarged view in which a part of FIG. 1 is omitted.

FIG. 3 is an enlarged cross-sectional view taken along line III-III of FIG.

FIG. 4 is a view corresponding to FIG. 2 when the valve body is in a fully opened state.

[Explanation of symbols]

 3 valve rod support member 4 valve rod 5 valve body 6 fluid passage 8 valve seat 14A pipe (lower tubular body) 14C pipe (upper tubular body) 17 connecting member 18 shake prevention member A valve body B valve operating part

Claims (1)

[Claims] 1. A valve body having a fluid passage and a valve seat, a valve operating portion, a valve rod support member having an upper end fixed to the valve operating portion and a lower end fixed to the valve body, and a valve rod support member. A valve rod whose upper end is connected to the valve operating part and whose lower end is in the valve body, and a valve element attached to the lower end of the valve rod. Moves the valve body up and down, and the valve body moves downward, which contacts and seats the valve seat to close the fluid passage, and the valve body moves upward, causing it to move away from the valve seat. In a control valve configured to open a fluid passage, a valve rod support member has an upper tubular body whose upper end is fixed to a valve operating portion and whose lower end is separated from a valve body, and whose lower end is fixed to a valve body. Lower tubular body whose upper end is separated from the valve operating part with Both tubular bodies are fitted to each other at a distance, the lower end of the upper tubular body and the upper end of the lower tubular body are connected by a connecting member, and the free end of the tubular body located outside is swung. A control valve equipped with a shake prevention member that prevents