JP2020197233A - valve - Google Patents

Abstract

To provide a valve having a life that is extended by mitigating uneven wear at a surface of an abutment part of a valve element and a surface of an abutment part of a valve seat which is caused by inclination of a stem.SOLUTION: A valve includes: a valve body having a flow channel; a valve element that vertically moves and abuts on a valve seat provided in the valve body to open and close the flow channel; a stem including the valve element at the tip thereof; and an actuator for vertically moving the stem. The valve element and the stem are connected by a universal joint, whereby an angle between a shaft of the valve element and a shaft of the stem is variable.SELECTED DRAWING: Figure 1

Description

The present invention relates to a valve that controls the flow rate of a fluid.

A control valve as described in Patent Document 1 is known as a control valve capable of adjusting the flow rate of a fluid to open and close it. As shown in FIG. 6, the control valve 101 includes a valve body 102 having a fluid inflow port 121, an inflow passage 123, an outflow passage 124, and an outflow outlet 122, a valve body 103 that controls a fluid flow rate, and a valve body. It includes an actuator 104 that moves the 103 up and down. When the valve is closed, the valve body contact surface 132 of the valve body 103 abuts on the valve seat 164 formed on the valve body 102 as the stem 105 is lowered by the actuator 104 to shut off the fluid.

The stem 105 penetrates the inside of the bonnet 108 arranged above the valve body 102, the bonnet 108 and the actuator 104 are connected by a yoke 109, and the shaft 141 of the actuator 104 and the stem 105 are connected by a connecting structure 110. Then, the rotational motion of the motor of the actuator 104 is converted into the axial linear motion of the stem 105.

These control valves have a structure that can withstand a high-pressure fluid by strongly pressing the valve body against the opposing valve seats by vertical movement without rotation.

JP-A-2016-014405

In recent years, control valves for flow rate adjustment and shut-off valves that can be turned on and off can be used in high-pressure and extremely low-temperature environments such as hydrogen station supply infrastructure and in high-pressure and extremely low-temperature environments such as manufacturing infrastructure using reaction gas. Is required.

In such a valve used in an extremely low temperature or high temperature environment, when the valve body portion is exposed to the extremely low temperature or high temperature, the stem connected to the valve body becomes hot or is cooled to a low temperature. When the stem becomes hot or cold, the actuator connected to the stem gets hot or is cooled to a low temperature, so that the actuator is adversely affected. In order to reduce the influence on the actuator, a measure to increase the length of the stem is generally taken.

Increasing the length of the stem can cause an unacceptable level of misalignment between the valve body and the valve seat, even if the stem is slightly tilted, which can lead to seat leaks or valve body-to-valve seat contact. It causes a decrease in valve life due to uneven wear of the surface.

An object of the present invention is to alleviate the occurrence of uneven wear due to the inclination of the stem between the contact portion surface of the valve body and the contact portion surface of the valve seat, and to provide a valve having a long life.

The present invention (1) includes a valve body having a flow path, a valve body that abuts on a valve seat provided in the valve body by vertical movement to open and close the flow path, and a stem having the valve body at its tip. A valve having an actuator for moving the stem up and down, the valve body and the stem are connected by a universal joint, and the angle between the axis of the valve body and the axis of the stem can be changed. It is a valve characterized by that.

By connecting the valve body and the stem with a universal joint, which is a universal joint, even if the stem is slightly tilted, the axis of the valve body is in contact with the valve seat on the contact surface with the valve seat. Since it is tilted so that the surface pressure is applied uniformly to the surface, it is possible to alleviate the occurrence of uneven wear due to the bias of the stem to the surface of the contact portion of the valve body and the surface of the contact portion of the valve seat.

In the present invention (2), the universal joint comprises a sliding body including a spherical surface portion and an aspherical surface portion connected to the spherical surface portion, and an aspherical body that surrounds the sliding body so as to be slidable and rotatable. The valve according to the present invention (1), characterized in that the angle between the axis of the valve body and the axis of the stem is limited by the size of a predetermined gap between the valve body and the surrounding body.

In general, a universal joint can transmit a force even if it is tilted by several tens of degrees, but the universal joint used in the present invention only needs to be able to correct a slight tilt, and therefore, as in the present invention (2), a sliding body. It is preferable that the angle can be corrected by the size of a predetermined slight gap between the aspherical portion and the surrounding body. The universal joint used in the present invention (2) is a so-called ball-and-socket type.

The present invention (3) is characterized in that the sliding body is formed at the stem side end of the valve body, and the surrounding body is formed at the valve body side end of the stem (2). It is a valve of.

Since the sliding body is formed at the stem side end of the valve body and the surrounding body is formed at the valve body side end of the stem, a universal joint is easily formed, which leads to a reduction in manufacturing cost.

In the present invention (4), the spherical portion is a sphere formed at the stem-side end of the valve body, the aspherical portion is a columnar neck portion connected to the spherical portion, and the surrounding body is From the stem having a recess formed at the valve body side end of the stem, and a support having a spherical concave surface that is accommodated and fixed in the recess and through which the neck portion penetrates and the spherical portion. The valve of the present invention (3), wherein the angle between the axis of the valve body and the axis of the stem is determined by the size of the gap between the neck portion and the inner peripheral wall of the through hole.

The present invention (4) is characterized in that the shapes of the sliding body and the surrounding body are, for example, the form of a universal joint as shown in FIGS. Since the limited angle can be easily determined by the size of the gap between the neck portion and the inner peripheral wall of the through hole, the valve can be driven stably.

In the present invention (5), the spherical portion is formed at the stem end portion of the valve body and has a spherical surface at the top, and the aspherical portion is a columnar neck portion connected to the spherical portion. The surrounding body is the stem having a recess formed at the valve body side end portion of the stem, and the recess is connected to a first recess accommodating the aspherical portion and the first recess. It is provided with a second recess having a step portion that accommodates the spherical portion and faces the surface of the spherical portion on the valve seat side, and is provided with a notch on the side surface so that the sliding body can be accommodated. It consists of a stem and a pin fixed to the stem and restricting the movement of the sliding portion to the notch side, and the angle between the axis of the valve body and the axis of the stem is the angle between the neck portion and the first recess. The valve according to the present invention (3), which is determined by the first gap between the inner peripheral wall and the inner peripheral wall.

The present invention (5) is characterized in that the shapes of the sliding body and the surrounding body are, for example, the form of a universal joint as shown in FIGS. 4 and 5. Since the limited angle can be easily determined by the first gap between the neck portion and the inner peripheral wall of the first recess, the valve can be driven stably.

According to this control valve, it is possible to alleviate the occurrence of uneven wear due to the inclination of the stem on the surface of the contact portion of the valve body and the surface of the contact portion of the valve seat, and to provide a valve having a long life.

It is a partial vertical sectional view which shows the whole of 1st Example of the valve by this invention. It is an enlarged view around the universal joint of the 1st Example of the valve by this invention. It is a partial cross-sectional plan view (a) and a partial cross-sectional front view (b) which are further enlarged views of FIG. It is an enlarged view near the universal joint of the 2nd Example of the valve by this invention. It is a partial cross-sectional plan view (a) and a partial cross-sectional front view (b) which are further enlarged views of FIG. It is an overall view of the conventional control valve with a long stem.

Hereinafter, preferred embodiments of the present invention will be described in detail, exemplary, with reference to the drawings. However, unless otherwise specified, the materials, shapes, relative arrangements, etc. of the components described in this embodiment are not intended to limit the scope of the present invention to them, but are merely explanatory examples. Absent.

As shown in FIG. 1, the valve 1 includes a valve body 2 having a flow path, a valve body 3 that opens and closes the flow path of the valve body 2 by vertical movement, and an actuator 4 that moves the valve body 3 up and down. There is. The actuator 4 is provided with a shaft 41 that moves up and down by the operation of the actuator 4. The shaft 41 and the valve body 3 are connected by a stem 5. In the connection between the shaft 41 and the stem 5, the connection structure 10 described in Patent Document 1 is provided.

The control valve 1 includes a bonnet 8 connected to the upper part of the valve body 2 and a yoke 9 connecting the bonnet 8 and the actuator 4.

The valve body 2 is provided with a valve body protrusion 26 formed on the central upper surface, a valve body recess 25 for accommodating the bonnet 8 through which the valve body 3 is inserted, and the connection of the bonnet 8 to the valve body 2 is a bonnet 8. It is done by a bonnet nut 81 attached to.

The valve body 2 has an inflow port 21 through which the fluid flows, an inflow passage 23 that guides the fluid from the inflow port 21 to the valve body 3, and a valve seat contact surface that contacts the contact portion 32 (see FIG. 2) of the valve body 3. A valve seat bolt 6 formed with 64 (see FIG. 2) is provided. An outflow passage 24 which is a passage for flowing out the fluid and an outflow outlet 22 which is an outlet for discharging the fluid to the outside of the valve body 2 are provided.

An O-ring 83 is provided inside the bonnet 8 while being held by the O-ring holder 82, and the O-ring 83 prevents fluid from leaking from the gap between the inner surface of the bonnet 8 and the outer surface of the stem 5. It has become. A gland packing 84 is interposed in the lower part of the O-ring holder 82. The gland packing 84 is formed of, for example, a hard synthetic resin such as PFA or PTFE, and together with the O-ring 83, prevents fluid from leaking from the gap between the inner surface of the bonnet 8 and the outer surface of the stem 5. A load is applied from above by the packing presser screw 85 to ensure the sealing property of the gland packing 84.

The yoke 9 is connected to the lower end surface of the actuator 4 by a screw (not shown), and the lower portion of the yoke 9 is screwed into a screw hole formed at the center of the yoke 9 with a male screw portion formed on the upper outer surface of the tubular portion of the bonnet 8. It is worn so that the bonnet 8 and the actuator 4 are connected by a yoke 9.

The opening degree of the control valve can be confirmed from the indicator 51 provided on the stem 5 and the indicator scale 91 attached to the yoke 9.

FIG. 2 is an enlarged view of the vicinity of the universal joint of the first embodiment shown in FIG. A valve seat bolt 6 having a valve seat bolt head portion 63 provided with a valve seat contact surface 64 is screwed into the valve body 2 by a valve seat bolt male screw portion 61. A valve seat bolt through hole 62 is formed inside the valve seat bolt 6, and the inflow passage 23 and the valve body recess 25 are inserted through the valve seat bolt 6. The valve body 2 and the bonnet 8 are screwed together by a male screw 26a on the protruding portion of the valve body and a female screw 81a on the bonnet nut.

From the top, the valve body 3 includes a valve body head 35 having a spherical surface portion 35a, a neck portion 34, a valve body body portion 33, a valve body contact portion 32, and a valve body tip portion 31. The valve body head 35 having the spherical surface portion 35a and the neck portion 34 form a sliding body.

A recess 52 (see FIG. 3B) is provided at the lower end of the stem 5, and a sliding body is fitted in the recess 52.

FIG. 3 is a further enlarged view of FIG. A recess 52 is formed at the end of the stem 5, and the valve body head 35 and the neck portion 34 are fitted therein, and the apex of the spherical portion of the valve body head is the bottom surface of the recess which is the ceiling surface of the recess 52. It is fitted so as to come into contact with 52a.

The valve body head receiving member 36 having a spherical concave surface 36a supports the valve body head spherical portion 35a in the valve body ball portion receiving member 36. The valve body head receiving member 36a is divided into four in the first embodiment. The reason for the division is that the valve body head 35 and the valve body 33, which are larger than the diameter of the neck 34, are located above and below the valve body head receiving member 36 through which the neck 34 penetrates, and are integrated. This is because these upper and lower parts do not fit. In the first embodiment, it is divided into four, but it can also be divided into two or three.

To assemble this part, a valve body head receiving member 36 is attached around the neck portion 34, inserted into the recess 52 until the valve body head spherical portion 35a abuts on the bottom surface 52a of the recess, and the pin 53 is driven. Do it with. The valve body head receiving member 36 is supported by the pin 53.

The surrounding body in the first embodiment corresponds to the end portion of the stem 5 provided with the recess 52 and the valve body head receiving member 36 (bearing body).

The valve body head receiving member 36 is provided with a through hole 37 for accommodating the neck portion 34, and the diameter of the through hole 37 is larger than the diameter of the neck portion 34, and a gap 38a is formed between the two. ing. Depending on the size of the gap 38a, the angle of intersection between the stem shaft and the valve body shaft can be changed within a limited angle range. When the gap 38a is large, the changing angle becomes large, and when the gap 38a is small, the changing angle becomes small.

FIG. 4 is an enlarged view of the vicinity of the universal joint according to the second embodiment of the present invention. A part of the same parts as in the first embodiment (FIG. 2) will be omitted.

A valve body head 35 having a main body portion 35b connected below the spherical surface portion 35a is formed on the upper portion of the valve body 3.

From the top, the valve body 3 has a valve body head 35 having a spherical body portion 35a and a cylindrical main body portion 35b, a neck portion 34 having a diameter smaller than that of the valve body head 35, a valve body body portion 33, and a valve body contact portion 32. The valve body tip portion 31 is provided. The valve body head 35 having the spherical surface portion 35a and the main body portion 35b and the neck portion 34 form a sliding body.

FIG. 5 is a further enlarged view of FIG. A first recess 54 for accommodating the neck portion 34 is formed at the end of the stem 5, and a second recess 55 for accommodating the valve body head 35 is formed above the first recess 54. The valve body head 35 is supported by a step portion 55b between the first recess 54 and the second recess 55, and the neck portion 34 and the valve body head 35 can be accommodated in the first recess and the second recess. One side of the stem 5 is cut out as described above.

The apex of the spherical portion 35a and the bottom surface 55a of the second recess, which is the ceiling surface of the second recess 55, come into contact with each other when the stem 5 moves downward and presses the valve body 3. When not pressed, a slight gap is provided. In FIG. 5, this slight gap corresponds to the gap between the main body portion 35b and the step portion 55b.

A through hole is formed on the side surface of the stem 5 via a notch, and a pin 53 is inserted into the stem 5. The movement of the neck portion 34 in the plane direction is restricted by the pin 53 and the inner peripheral wall 54a of the first recess. The size of the gap 38b between the neck portion 34 and the inner peripheral wall 54a and the pin 53 of the first recess changes the angle of intersection between the stem axis and the valve body axis within a limited angle range. You can do it. If this gap is large, the changing angle becomes large, and if this gap is small, the changing angle becomes small.

The end of the stem 5 having the first recess 54 and the second recess 55 and the pin 53 correspond to the surrounding body in the second embodiment.

1: Control valve 2: Valve body 3: Valve body 4: Actuator 5: Stem 8: Bonnet 9: Yoke 10: Connection structure 21: Inflow port 22: Outlet 23: Inflow passage 24: Outflow passage 25: Valve seat 26: Valve body protrusion 26a: Valve body protrusion male screw 31: Valve body tip 32: Valve body contact 33: Valve body 34: Neck 35: Valve head 35a: Spherical portion 35b: Main body 36: Valve Body head receiving member 36a: Spherical concave surface 37: Through hole 38a: Gap 38b: First gap 41: Shaft 51: Indicator 52: Recess 52a: Recess bottom surface 53: Pin 54: First recess 54a: First concave Inner peripheral wall 55: Second recess 55a: Second recess bottom 55b: Step 55c: Inner peripheral wall of the second recess 61: Valve seat bolt Male thread 62: Valve seat bolt through hole 63: Valve seat bolt Head portion 64: Valve seat contact surface 81: Bonnet nut 81a: Bonnet nut female screw 82: O-ring holder 83: O-ring 84: Gland packing 85: Packing holding screw 91: Indicator scale

Claims (5)

A valve body with a flow path and
A valve body that opens and closes the flow path by contacting the valve seat provided on the valve body by vertical movement.
A stem having the valve body at the tip and
A valve having an actuator for moving the stem up and down.
A valve characterized in that the valve body and the stem are connected by a universal joint, and the angle between the axis of the valve body and the axis of the stem can be changed. The universal joint is composed of a sliding body having a spherical surface portion and an aspherical surface portion connected to the spherical surface portion, and a surrounding body that surrounds the sliding body so as to be slidable and rotatable, and is between the aspherical surface portion and the surrounding body. The valve according to claim 1, wherein the angle between the shaft of the valve body and the shaft of the stem is limited by a predetermined gap size. The valve according to claim 2, wherein the sliding body is formed at a stem-side end portion of the valve body, and the surrounding body is formed at a valve body-side end portion of the stem. The spherical surface portion is a sphere formed at the stem side end portion of the valve body.
The aspherical portion is a columnar neck portion connected to the spherical portion.
The surrounding body includes the stem having a recess formed at the valve body side end portion of the stem, a through hole that is accommodated and fixed in the recess, and a spherical concave surface that supports the spherical portion. Consists of bearings
The valve according to claim 3, wherein the angle between the axis of the valve body and the axis of the stem is determined by the size of the gap between the neck portion and the inner peripheral wall of the through hole. The spherical portion is formed at the stem end of the valve body and has a spherical surface at the top.
The aspherical portion is a columnar neck portion connected to the spherical portion.
The surrounding body is the stem having a recess formed at the valve body side end portion of the stem, and the recess is connected to a first recess accommodating the aspherical portion and the first recess. It is provided with a second recess having a step portion that accommodates the spherical portion and faces the valve seat side surface of the spherical portion, and is provided with a notch on the side surface so that the sliding body can be accommodated. It consists of a stem and a pin fixed to the stem and restricting the movement of the sliding portion to the notch side, and the angle between the axis of the valve body and the axis of the stem is the angle between the neck portion and the first recess. The valve according to claim 3, which is determined by a first gap between the inner peripheral wall and the inner peripheral wall.

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