JP2001248745A - Ball valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ball valve in which an O ring is not damaged and a twisting is not generated when the ball valve is assembled. SOLUTION: In the ball valve, a ball 2 capable of opening/closing a flow passage is disposed in a valve element; ball seats 4 are abutted to the ball 2 from both sides of the flow passage; both ball seats 4, 4 are urged to the ball 2 by ball keepers 5, 5 in which a male screw 51 provided on an outer periphery is thread-engaged with female screws 11, 11 provided on an inner periphery at both opening ends of the valve element 1. Annular grooves 13, 13 are provided on an inner periphery of the valve element 1 at a deep side as compared with the female screws 11, 11 and O rings 14 are attached to both annular grooves 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a ball valve.

[0002]

2. Description of the Related Art As a conventional ball valve, a ball capable of opening and closing a flow path is disposed in a cylindrical valve body, and a ball sheet is brought into contact with the ball from both sides of the flow path. There is a so-called union type ball valve which is pressed against a ball by a certain union. In this ball valve, by connecting the connection sleeve to the valve body, the union is pushed by the connection sleeve and pressed toward the ball.

For example, as shown in FIG. 2, the union 3a is pressed by the connection sleeve 4a connected to the valve body 1a by the union nut 5a, and the ball 2a and the ball seat 6a are adjusted by adjusting the tightness of the union nut 5a. Is adjusted so that the contact pressure with
When the ball seat 6a wears and fluid leakage occurs, the union nut 5a is tightened to prevent leakage.

The biggest disadvantage of this type of ball valve is that when the ball 2a closes the flow path and the fluid pressure is maintained on one side of the ball 2a, the union nut 5a and the connection sleeve 4a on the opposite side are used. Cannot be removed. That is, when repair or replacement of the pipe connected to the connection sleeve 4a is required,
The connection sleeve 4a must be removed by loosening the union nut 5a. However, when the connection sleeve 4a is removed, the ball 2a and the union 3a pop out of the valve main body 1a due to pressure, which involves a danger.

[0005] As a ball valve which has solved this disadvantage,
For example, in Japanese Utility Model Laid-Open Publication No. 57-105474, a female screw 14a is provided on the inner peripheral surface of the opening end of the valve body 1a, while a male screw 15a is provided on the outer peripheral surface of the union 3a on the side of the connection sleeve 4a. There is disclosed one in which the union 3a is prevented from jumping out by screwing the 15a into the female screw 14a of the valve body 1a (see FIGS. 3 and 4).

[0006]

By the way, in the ball valve disclosed in the above publication, in order to ensure watertightness between the inner peripheral surface of the valve body 1a and the outer peripheral surface of the union 3a,
Since the annular groove 10b is provided on the outer peripheral surface of the union 3a located on the back side of the male screw 15a, and the O-ring 10a is mounted in the annular groove 10b in a watertight manner, the union is formed on the female screw 14a of the valve body 1a. 3a male screw 15a
When the ball valve is assembled by screwing together, the O-ring 10a mounted on the annular groove 10b of the union 3a goes over the female screw 14a at the open end of the valve body 1a and proceeds to the back side. As a result, the O-ring 10a is
Damaged at the peak of 4a or O-ring 10
There was a problem that twisting occurred in a and watertightness was reduced.

An object of the present invention is to provide a ball valve in which an O-ring is not damaged and twisting does not occur when the ball valve is assembled.

[0008]

According to a first aspect of the present invention, there is provided a valve body having a ball capable of opening and closing a flow path, and a ball seat contacting the ball from both sides of the flow path. At least one of the seats is pressed toward the ball by a ball retainer in which a male screw provided on the outer peripheral surface is screwed into a female screw provided on the inner peripheral surface on the opening end side of the valve body. In the ball valve, an annular groove is provided on the inner peripheral surface of the valve body on the back side of the female screw, and an O-ring is mounted in the annular groove in a watertight manner.

(Operation) In the first aspect of the present invention, since the O-ring is mounted in a watertight manner in the annular groove provided on the inner peripheral surface of the valve body on the back side of the female screw, the ball seat can be removed. When the male screw of the ball retainer is screwed into the female screw of the valve body to press the ball toward the ball, the O-ring does not contact the female screw of the valve body. Therefore, the O-ring is not twisted or damaged.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a semi-longitudinal sectional view showing a first embodiment of a ball valve V of the present invention. The ball valve V is made of a hard vinyl chloride resin.

In FIG. 1, reference numeral 1 denotes a valve body, in which a ball 2 is inserted into the valve body 1, and a spindle 3 penetrating a wall surface of the valve body 1 is fitted into a concave groove 21 of the ball 2. A ball sheet 4 is applied to both sides of the ball 2, and both ball pressers 5, 5 are inserted and held. The ball seat 4 is supported by being fitted into a ball retainer 5. A union nut 7 is screwed into a male screw 11 on the outer periphery of the end of the valve body 1, and the union nut 7 presses the connection sleeve 6 toward the ball retainer 5 to connect to the pipe. Reference numeral 8 denotes a handle, which is mounted on the upper end of the spindle 3.

The engagement and holding of the ball holders 5 and 5 with the valve main body 1 are provided on both inner female threads 12 and 12 provided on the inner peripheral surfaces of the valve main body 1 on both open ends and on the outer peripheral surface of the ball retainer 5. This is performed by screwing with the male screw 51 provided. Female screw 12
An annular groove 13 is provided on the inner peripheral surface of the valve body 1 located on the farther side than the O-ring 1.
4, 14 are attached.

The outer diameter of the ball 2 is set to be slightly smaller than the inner diameter of the ridge of the female screw 12 of the valve body 1 when the ball 2 is oriented in the direction in which the flow path is closed.

A male screw 51 is provided on the outer peripheral surface of the ball retainer 5, and an annular groove 53 for mounting an O-ring 531 is provided on an end surface located on the male screw 51 side. Small recesses (not shown) are provided at two opposing ends of the end face located outside the annular groove 53. The recess is used to lock the tip of a rotating jig (not shown) and turn the ball retainer 5 when the male screw 51 of the ball retainer 5 is screwed into the female screw 12 of the valve body 1. An annular locking groove 54 for fitting and supporting the ball seat 4 is provided on the inner surface of the ball holder 5 on the side of the ball 2.

An O-ring 531 is mounted in the annular groove 53 to prevent leakage from between the ball retainer 5 and the inner peripheral surface of the valve body 1 and the connection sleeve 6. The ball seat 4 is mounted in the locking groove 54 via an O-ring 541.

In order to assemble the ball valve V having the above structure, the spindle 3 is inserted into the valve body 1 through the through hole 10 and the lower end of the spindle 3 is projected into the valve body 1. It is inserted from the end of the valve body 1 in the direction in which the flow passage hole 20 is closed, and is fitted to the lower end of the spindle 3.

At this time, in a state where the outer diameter of the ball 2 is directed toward the direction in which the flow path is closed, the valve body 1
Since the inner diameter of the female thread 12 is slightly smaller than the inner diameter of the female thread 12, the ball 2 can be inserted into the valve main body 1 from the open end side of the valve main body 1.

Next, the ball holder 5 having the O-ring 541 and the ball seat 4 mounted inside the tip is inserted into the valve body 1 with the side on which the ball seat 4 is mounted facing forward, and the ball holder 5 is rotated and fixed. Turn in the circumferential direction with the tool,
The male screw 51 of the ball retainer 5 is connected to the female screw 12 of the valve body 1.
Then, the contact pressure between the ball 2 and the ball sheet 4 is adjusted to a predetermined pressure by the ball seat 4 mounted in the locking groove 54 of the ball retainer 5.

The annular groove 53 on the end face of the ball retainer 5
An O-ring 531 is attached to the connection sleeve 6, and the union nut 7 is screwed into a male screw 11 on the outer periphery of the end of the valve body 1, and the connection sleeve 6 is pressed toward the ball retainer 5, and The handle 8 is fitted to the upper end to complete the assembly of the valve V.

In the ball valve of the first embodiment, both annular grooves 13 are provided on the inner peripheral surface of the valve body 1 located on the back side of both internal threads 12, and O-rings 14 are respectively provided in both annular grooves 13. When the male screw 51 of the ball retainer 5 is screwed with the female screw 12 of the valve body 1,
The O-ring 14 is not twisted or damaged.

In the above embodiment, the ball valve is made of resin, but may be made of metal. Further, although the valve body 1 is of the double carrier type, it may be of the single carrier type.

[0022]

In the ball valve according to the first aspect of the present invention, since the O-ring is mounted in the annular groove provided on the inner peripheral surface of the valve body on the back side of the internal thread, the internal thread of the valve body is provided. When screwing the male screw of the ball retainer, the O-ring does not come into contact with the female screw of the valve body, so that the O-ring is not twisted or damaged. For this reason, the water tightness by the O-ring is kept good.

[Brief description of the drawings]

FIG. 1 is a semi-longitudinal sectional view showing a first embodiment of a ball valve of the present invention.

FIG. 2 is a partial vertical sectional view showing a conventional ball valve.

FIG. 3 is a partial longitudinal sectional view showing another conventional ball valve.

FIG. 4 is an enlarged sectional view showing a main part of FIG.

[Explanation of symbols]

 V Ball valve 1 Valve body 11 Male thread 12 Female thread 13 Annular groove 14 O-ring 2 Ball 3 Spindle 4 Ball seat 5 Ball retainer 6 Connection sleeve 7 Union nut

Claims (1)

[Claims] 1. A ball which can open and close a flow path is disposed in a valve body, and a ball sheet is brought into contact with the ball from both sides of the flow path, and at least one of the ball sheets is provided on an opening end side of the valve body. In a ball valve in which a female screw provided on an inner peripheral surface thereof is pressed toward a ball by a ball retainer screwed with an external screw provided on an outer peripheral surface thereof, a valve body deeper than the female screw is provided. A ball groove provided on an inner peripheral surface of the ball valve, and an O-ring is mounted in the annular groove in a watertight manner.