JPH08219299A - Sluice valve - Google Patents

Abstract

PURPOSE: To provide a sluice valve capable of preventing an accident due to the excessive torque to be applied when the valve is fully closed, and facilitating the adjustment of an excessive tightening preventing mechanism. CONSTITUTION: A sluice valve is provided with a valve casing 11 provided with a fluid passage 15a and a valve chamber 15b extended in the vertical direction thereto, a yoke 17 which is located above the valve casing 11 and supports a valve stem 12, the valve stem 12 which is provided with a male screw 121 and elevated/lowered, and a valve element 13 which is fitted to the valve stem 12 and elevated/lowered in the valve chamber 15b together with the valve stem 12 and opens/closes the fluid passage 15a. An excessive tightening preventing ring 40 is provided on a part to be exposed above the yoke 17 of the valve stem 12 in an elevating/lowering manner by the screw, and an upper end face 172 if an abutting surface sleeve 171 on which the excessive tightening preventing ring 40 when the valve is fully opened is formed on the piercing part of the valve stem 12 above the yoke 17.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an external screw type sluice valve suitable for use in pipelines for agricultural and marine equipment, water treatment equipment, construction equipment, plant equipment, water supply and the like.

[0002]

2. Description of the Related Art When a sluice valve is fully closed, a valve body collides with a valve seat provided in a valve box to close the valve, but the handle of a valve rod is operated with an excessive torque. In this case, since the valve stem presses the valve body strongly against the valve seat, excessive load may damage the valve body or the valve seat or cause excessive stress on the valve box, which may cause cracking. . In particular, in recent years, valve valves and valve bodies made of synthetic resin material are widely used as gate valves that are lightweight and have excellent corrosion resistance. When the mechanical strength is low and an excessive closing operation is performed, the valve box or the valve body may be damaged by the stress generated in the contact portion between the valve box and the valve body.

Therefore, in order to prevent such an accident due to overtightening of the valve, Japanese Utility Model Laid-Open No. 5-45367 discloses an overtightening prevention structure for a sluice valve. In this overtightening prevention structure, a stopper (an overtightening prevention mechanism) for restricting relative screw fitting of the valve rod with respect to the handle is provided at the valve shutoff position of the valve rod screwed with the handle.

[0004]

[Problems to be Solved by the Invention]
In the overtightening prevention structure described in Japanese Patent Publication No. 45367-, since the stopper position is fixed, there is a manufacturing error in the valve, or the valve seat or the valve element wears due to the opening / closing operation of the valve, and the valve shutoff position. If it changes, it is necessary to re-drill the pin fixing hole at another position of the valve rod to adjust the position of the stopper, which requires time and labor.

The present invention has been made in view of the above problems in the conventional gate valve described above, and an accident caused by exerting an excessive torque by exerting a function of preventing overtightening when the valve is fully closed. It is an object of the present invention to provide a sluice valve capable of reliably preventing the above-mentioned problem and easily adjusting the position of the overtightening prevention mechanism.

[0006]

In order to achieve the above object, a sluice valve of the present invention includes a valve box having a fluid passage and a valve chamber extending in a direction perpendicular to an axis of the fluid passage, and a valve box. A sluice valve having a yoke for supporting the valve rod on the upper side, a valve rod having a male screw for moving up and down, and a valve body attached to the valve rod for moving up and down in the valve chamber together with the valve rod to open and close a fluid flow path. An overtightening prevention ring is provided on the exposed part of the yoke of the rod so that it can be raised and lowered by a screw, and an abutment surface against which the overtightening prevention ring abuts when the valve is fully closed at the valve rod penetrating part on the yoke. What is formed is the gist.

In the present invention, the means for raising and lowering the valve rod is not particularly limited. For example, a male screw is engraved on the valve rod, and a sleeve provided with a female screw to be engaged with the male screw is provided, and this sleeve is provided on the yoke. A means for rotating the sleeve may be used, and a means for rotating the sleeve may be a manual handle, a gear mechanism, a cap and box spanner of an embedded valve, a means for rotating by a power driving device using an electric motor, or the like. Etc. can be used.

[0008]

According to the sluice valve of the present invention, when the valve body abuts against the inner surface (valve seat) of the fluid passage and the valve is fully closed, the overtightening prevention ring is formed on the abutment surface formed in the valve rod penetrating portion. Adjust the height of the overtightening prevention ring so that it strikes against each other, then lower the valve rod by the means for raising and lowering it, and bring the valve element into contact with the inner surface (valve seat) of the fluid flow path to fully close the valve. Then, at the same time when the valve is fully closed, the overtightening prevention ring abuts against the abutment surface, and the valve stem cannot be further lowered. This prevents excessive torque from being applied to the valve disc, the valve rod, the mounting portion of the valve disc and the valve rod, the valve box, the lid, the yoke, and the like. The overtightening prevention ring is located on the exposed portion of the yoke and is raised and lowered by a screw. Therefore, the height of the overtightening prevention ring with respect to the valve rod can be arbitrarily and easily adjusted by rotating the overtightening prevention ring to the right or left and moving it up and down.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing a fully closed state of the embodiment of the present invention.

As shown in FIG. 1, the sluice valve 10 is a valve box 1
1, a valve rod 12, a valve body 13, and a handle 14.
The valve box 11 is configured by fastening the housing 15, the inner lid 16 and the yoke 17 together from below in this order with several fixing bolts 18. The housing 15 also includes a fluid channel 15a and a valve chamber 15b extending in a direction perpendicular to the axis of the fluid channel 15a.

The valve rod 12 penetrates the yoke 17 and the inner lid 16, and the upper end portion of the valve rod 12 extends above the yoke 17 and is screwed with a male screw 121.

A sleeve 171 is fitted on the upper portion of the yoke 17, and the male screw 121 of the valve rod 12 is fitted into the sleeve 171.
A female screw to be screwed with is engraved. The handle 14 is fitted into a portion of the sleeve 171 protruding above the yoke 17, and the handle 14 is fixed to the sleeve 171 by a handle holding nut 30 so as not to come out upward. As a result, the handle 14 is rotatably supported on the yoke 17 and does not move up and down with respect to the yoke 17. By rotating the handle 14, the sleeve 171 rotates, and the female screw and the screw thread engraved on the sleeve 171 are screwed. The mating valve rod 12 is a so-called "outer screw valve rod non-rotating" sluice valve that moves up and down without rotating.

Further, the upper end surface 172 of the sleeve 171 is formed in a plane perpendicular to the axis of the valve rod 12, and protrudes above the upper end surface of the tightened sleeve nut 30. The upper end surface 172 is an abutment surface against which an overtightening prevention ring described later abuts.

The lower end of the valve rod 12 reaches the inside of the valve chamber 15b, and the valve body 13 is connected to the lower end. Disc 13
Is provided with an engagement projection 20 slidably engaged with a guide groove provided on the inner surface of the valve chamber 15b along the axial direction of the valve rod.

The valve body 13 is of a so-called soft seal type, in which grooves are formed in the circumferential direction and the axial direction of the outer peripheral surface of the valve body body 13a, and an elastic packing 19 joined in a T-shape is formed in the groove. The valve body 13 is housed and is moved up and down in the axial direction by the valve rod 12, and the elastic packing 19 is pressed against or separated from the valve box 11 to open and close the fluid flow path 15a.

In the sluice valve 10, the housing 15, the inner lid 16, the yoke 17 and the valve body 13 constituting the valve box 11 are made of a synthetic resin material such as vinyl chloride or polypropylene from the viewpoint of ensuring corrosion resistance. The sleeve 171, the nut member, and the like, which are molded and screwed with the male thread 121 of the valve rod 12 and the valve rod 12, are made of metal such as stainless steel and brass having excellent mechanical strength and corrosion resistance.

An overtightening prevention ring 40 is provided at a portion of the valve rod 12 exposed above the yoke 17 (more precisely, above the sleeve 171), and a lock nut 50 is provided on the overtightening prevention ring 40. Are screwed together and are both rotated around the male screw 121 to move the valve rod 12 up and down in the axial direction.

In order to adjust the position of the overtightening prevention ring 40, the handle 14 is turned to rotate in the direction of closing the valve, and the valve rod 12 and thus the valve element 1 attached to the valve rod 12 is rotated.
3, the elastic packing 19 housed in the groove formed on the outer peripheral surface of the valve body 13a is moved to the valve box 11
When the handle 14 is made to abut against the bottom (valve seat) and the handle 14 is slightly rotated, the elastic packing 19 is compressed and the valve is closed. In this state, the lower surface 401 of the overtightening prevention ring 40 is abutted against the upper end surface 172 (abutting surface) of the sleeve 171, and the overtightening prevention ring 40 is locked and fixed by the lock nut 50.

In the sluice valve 10 in which the position of the overtightening prevention ring 40 is adjusted as described above, the lower surface 401 of the overtightening prevention ring 40 abuts the upper end surface 172 of the sleeve 171 at the same time when the valve body 13 is closed. , The valve rod 12 does not descend further,
Therefore, the members such as the valve body 13, the valve rod, the valve box 11 and the like are not subjected to an excessive load, so that damage to them is prevented.

FIG. 2 is a partially enlarged sectional view showing a partially opened state of a valve according to another embodiment of the present invention, and FIG. 3 is a partially enlarged sectional view showing a fully closed state of the gate valve shown in FIG. Valve rod 12
A screw hole 122 is provided at the tip of a. A position adjusting bolt 60 is screwed into the screw hole 122, and an overtightening prevention ring 41 having an outer diameter larger than the inner diameter of the screw hole 122 is integrally attached to the other end of the position adjusting bolt 60. A set of lock nuts 51 having an outer diameter smaller than the inner diameter of the female screw threaded on the sleeve 171 is screwed onto the position adjusting bolt 60.

To adjust the position of the overtightening prevention ring 41, the valve is shut off in the same manner as described above, and the position adjusting bolt 60 is moved in this state to move the lower surface 4 of the overtightening prevention ring 41.
11 is brought into abutment with the upper end surface 172 of the sleeve 171, and the lock nut 51 is brought into contact with the tip end surface 123 of the valve rod 12a and locked.

In this sluice valve, when the valve is closed, the front end surface 123 of the valve rod 12a sinks into the sleeve 171 below the upper end surface 172 thereof, and when the valve is closed, the lower surface 411 of the overtightening prevention ring 41 is sleeved. Upper end surface 172 of 171
The valve rod 12a does not further descend due to the collision with the above, and therefore damage due to overtightening is prevented. In the sluice valve of this embodiment, the diameter of the overtightening prevention ring, the position adjusting bolt 60 and the like can be reduced, so that the overtightening prevention mechanism can be made compact.

FIG. 4A is a partially enlarged sectional view showing a partially opened state of the valve in still another embodiment of the present invention, and FIG. 4B is a sectional view taken along line XX of FIG. . In the embodiment shown in FIG. 4, an overtightening prevention ring 42 is provided at a portion exposed above the sleeve 171 of the valve rod 12b, and a lock nut 52 is movable above and below the valve rod 12b in the axial direction. The point of being screwed is similar to that of the embodiment shown in FIG.

In the portion of the valve rod 12b exposed above the sleeve 171, two concave grooves 124 parallel to the axial direction are engraved. The washer 70 is placed on the sleeve 171. The washer 70 is made of synthetic resin such as ethylene tetrafluoride, vinylidene fluoride, and polyacetal, which has a large compressive strength and a small friction coefficient with a metal and is hard to wear, and has two protrusions 75 on its inner peripheral portion. It is projected. The protrusion 75 fits into the groove 124 formed in the valve rod 12b and is movable in the groove 124 in the vertical direction. Therefore, the washer 70 is stationary on the sleeve 171 without rotating and moving vertically with the valve rod 12b.

To adjust the position of the overtightening prevention ring 42, the valve is shut off in the same manner as described above, and in this state, the lower surface 421 of the overtightening prevention ring 42 is attached to the upper surface 70 of the washer 70.
1, and lock nut 52 to prevent overtightening ring 42
Lock and fix.

In this sluice valve, at the same time when the valve is closed, the lower surface 421 of the overtightening prevention ring 42 collides with the upper surface 701 of the washer 70, and the valve rod 12b does not descend further.
Therefore, damage due to overtightening is prevented.

Further, in the sluice valve shown in FIG. 4, a washer 70 made of synthetic resin, which has a large compressive strength and a small friction coefficient with metal, and which is hard to wear, is interposed between the overtightening prevention ring 42 and the sleeve 171. , When closing the valve, handle 1
Since the sleeve that rotates together with 4 does not abut the overtightening prevention ring 42 that does not rotate, the overtightening prevention ring 4
It is possible to prevent an accident in which the lower surface 421 of No. 2 and the upper surface 172 of the sleeve 171 are burned and damaged, or the valve cannot be opened and closed.

[0028]

According to the sluice valve of the present invention, when the valve rod is lowered and the valve body collides with the inner surface of the fluid flow path to fully close the valve, the overtightening prevention ring penetrates the valve rod on the yoke. It abuts against the abutment surface formed on the part, and the valve stem cannot be further lowered. By this, the valve body, the valve rod, the mounting portion of the valve body and the valve rod,
Excessive torque is prevented from being applied to the valve box, lid, yoke, etc., and damage is prevented. In addition, even if the valve closing position changes due to valve manufacturing errors or wear of the valve seat or valve body when opening and closing the valve, the valve can be rotated up and down to raise or lower the valve. The height of the overtightening prevention ring with respect to the rod can be adjusted arbitrarily and easily.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a fully closed state of an embodiment of the present invention.

FIG. 2 is a partially enlarged cross-sectional view showing a partially opened state of a valve according to another embodiment of the present invention.

FIG. 3 is a partially enlarged cross-sectional view showing a state where the valve of the embodiment shown in FIG. 2 is fully closed.

FIG. 4 is an explanatory view showing still another embodiment of the present invention, in which (A) is a partially enlarged sectional view showing a partially opened state of the valve,
(B) is sectional drawing which followed the XX of (A).

[Explanation of symbols]

 10 Gate Valve 11 Valve Box 12, 12a, 12b Valve Rod 121 Male Thread 124 Recessed Groove 13 Valve Body 14 Handle 15 Housing 15a Fluid Flow Path 15b Valve Chamber 17 Yoke 171 Sleeve 172 Upper End Surface (Abutting Surface) 19 Elastic Packing 40, 41 , 42 Overtightening prevention ring 50, 51, 52 Lock nut 70 Washer 75 Protrusion

Claims (1)

[Claims] 1. A valve box having a fluid passage and a valve chamber extending in a direction perpendicular to the axis of the fluid passage, a yoke for supporting the valve rod on the valve casing, and a valve rod having a male screw and moving up and down. In a sluice valve that has a valve element that is attached to the valve rod and moves up and down together with the valve rod to open and close the fluid flow path, an overtightening prevention ring can be raised and lowered by a screw on the exposed portion of the valve rod on the yoke. The sluice valve, which is provided on the yoke, has an abutment surface with which the overtightening prevention ring abuts when the valve is fully closed.