JPS59536Y2 - Valve with antistatic device - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a valve that is equipped with an antistatic device to prevent the valve body and operating stem from being charged with electricity.

In general, when a non-conductive fluid flows through a metal valve, or a ball valve or a plug valve whose metal valve body is held in the valve body through an electrically insulating valve seat made of synthetic resin, etc. It is widely known that static electricity is generated when the valve body is brought into sliding contact with an electrically insulating valve seat.

By the way, if the stem for operating the valve body and the valve body are electrically insulated due to their structure, or for some reason when the stem is operated,
The static electricity generated as described above will be charged to the valve body.

Therefore, due to the potential difference generated between the valve body and the valve body,
Electric discharge may occur between the valve body and the valve body, so please do not use such valves.
When used to control flammable fluids, there is a risk of ignition and explosion.

The structure of a conventional valve equipped with a device to prevent such danger will be explained with reference to FIGS. 1 to 3. In FIG. 5 is a metal valve box, 6 is a metal spherical valve body fitted into the valve box 1, and the valve body 6 has an inlet 2 and an outlet 3.
A lateral valve hole 6' is drilled therein, which can coincide with the lateral valve hole 6'.

The valve body 6 is supported by the inner surface of an annular valve seat 7 made of a wear-resistant synthetic resin and fitted into a communicating portion with the inlet 2 and outlet 3.

The lower end 8' of the vertical stem 8 is fitted into the center of the top surface of the valve body 6 in a non-rotatable manner, so that the valve body 6 and the stem 8
is conducting.

This stem 8 has a receiving tube 9 erected from the center of the upper surface of the valve body 1.
It is pivotally fixed to the body through a packing 10, a washer 11, and a sleeve 12 made of synthetic resin.

A recess 13 is formed at the center of the bottom surface of the valve body 6, that is, on an extension of the axis of the stem 8, and a recess 14' is provided at a portion of the valve body l facing the recess 13. '
A metal sphere 15 is interposed between them to support the bottom surface of the valve body 6, and the valve body 6 and the valve body 1 are electrically short-circuited via the sphere 15 to prevent static electricity.

The recess 14' in the valve case 1 is formed on the upper surface of the plug 14 which is screwed into the valve case 1 from below the center of the bottom surface thereof.

24 is a ground cover.

In FIG. 2, a conductive coil spring 16 is provided in place of the metal sphere 15 in FIG. 1.

In FIG. 3, instead of interposing the sphere 15 and the coil spring 16, a gland 18 is fastened to the flange 17 at the circle A shown in FIG. A hole 22 at the outer end of an elastic conductive plate 21 having a through hole 21 a in the center and fitted into the stem 8 is fitted into the lower surface of the head of the conductive plate 19. The upper surface of the peripheral edge of the through hole 21a of 21 is locked and pressed by a retaining ring 20 fitted at a key point of the stem 8, and the stem 8 and the valve box are connected via the retaining ring 20, the conductive plate 21, and the bolt 19. 1 is electrically short-circuited to prevent static electricity.

In addition to this, there are also valve bodies 6 and stems 8 each using a conductive member to prevent static electricity.

However, in all of the above conventional antistatic devices, the antistatic device is composed of multiple members, and special work must be done on the valve body or valve box, which requires time and effort to manufacture and increases costs. There was a drawback.

This invention has been developed in view of the above-mentioned conventional drawbacks and has been improved and eliminated. That is, the present invention provides a valve that can very easily prevent static electricity on the valve body by using one conductive spring. This is what I am trying to do.

Hereinafter, a description will be given of an embodiment of the configuration of this invention shown in the drawings.

4 to 6, B is an antistatic device which is a main part of the embodiment according to the present invention, 23 is a conductive spring, and other members are the conventional ones shown in FIGS. 1 to 3. It is similar to that of the valve.

Due to its elasticity, the spring 23 has a central portion 23 as shown in FIG.
a abuts and locks on the side surface of stem B, and both ends 23 b
is abutted against the side surface of the bolt 19 head.

Then, the stem 8 is connected via this spring 23 and bolt 19.
and the valve box 1 are electrically short-circuited to prevent static electricity.

Incidentally, since the spring 23 is prevented from moving in the axial direction by the retaining ring 25, it will not come off from the head of the bolt 19.

As is clear from the above explanation, the present invention is extremely easy to manufacture because it prevents static electricity using only one conductive spring without any modification to the conventional valve configuration, and is cost effective. can be kept extremely low.

The structure and operation of the valve with an antistatic device according to the present invention other than the antistatic device are the same as those of the conventional valve.

As explained above, this invention is based on a metal valve body that is supported in a metal valve body via an electrically insulating annular valve seat so as to be rotatable around a vertical axis. In a valve in which the lower end of a vertical operating stem is fitted in a non-rotatable manner, the center of one conductive spring is elastically locked to a part of the side surface of the stem, and the conductive spring is The antistatic device is configured by having both ends clamped onto the sides of the bolt that fastens the gland of the valve box, and by using a retaining ring to prevent movement in the axial direction, making it extremely easy to manufacture and cost effective. It is extremely useful as it can reduce the amount of water used.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a conventional valve with an antistatic device, FIGS. 2 and 3A are sectional views of main parts of another conventional valve with an antistatic device,
3B is a plan view of FIG. 3A, FIG. 4 is a sectional view of an embodiment of the present invention, FIG. 5 is an explanatory diagram of the main part of the present invention, and FIG. 6 is a plan view thereof. ... Valve box, 6... Valve body, 7...
- Valve seat, 8... Stem, 23... Conductive spring.

Claims (1)

[Scope of utility model registration request] At the center of the upper surface of the metal valve body, which is supported through an electrically insulating annular valve seat so as to be rotatable around a vertical axis, is a stem for vertical operation. In a valve whose lower end is fitted in a non-rotatable manner, the center part of one conductive spring is elastically locked to a part of the side surface of the stem, and both ends of this conductive spring are fastened to the ground of the valve body. A valve with an antistatic device, characterized in that it is elastically locked to the side surface of a bolt to which it is attached, and its movement in the axial direction is restrained by a retaining ring.