JPH1047495A - Underground fire hydrant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a size of a valve box, and reduce number of part items and a working manhour by forming an opening serving as a valve element insertion port and a fluid outlet on an upper portion of a valve box, integrating a valve rod supporting part with a part of the opening, and forming a valve rod insertion port. SOLUTION: A fluid inlet 2 is formed on a lower side, while an opening 3 serving as a valve element insertion part and a fluid outlet is formed on an upper side. A projection 4 as a valve rod supporting part is formed on a part of the opening 3 to form a valve rod insertion port 3A. The projection 4 is cast integrally with a valve box 1. A flange 6 of the valve rod 5 is mounted on the projection 4. A male screw 7 is threaded on the valve rod 5 at its lower side of the projection 4. A valve element 9 having a female screw 8 engaged with the male screw is seated on a valve seat 10 in the valve box 1 to block the fluid inlet 2. A hollow cylinder 12 of a cover part 11 is penetrated by a portion of the valve rod 5 upper than the flange 6. A cap 13 is formed on an upper end of the valve rod. A sealing member 14 is arranged around the valve rod 5 inside the hollow cylinder 12. It is thus possible to reduce number of part items and processes, and simplify a structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an underground fire hydrant of a type in which a valve is opened and closed by rotating a valve stem without moving up and down, installed in a pipeline.

[0002]

2. Description of the Related Art A general product of a single-port underground fire hydrant for water supply is a JWWA B103 standard product (see FIGS. 3 and 3).
A) is a valve rod ascending type in which the valve rod c is moved up and down by rotating the cap b when opening and closing the valve element a, although most types are internally screw type. In these figures, t indicates a valve presser, u indicates a set screw, and v indicates a rubber valve seat.

[0003] In an underground fire hydrant (single port) for water supply, the reason why the non-elevating valve type of the inner screw type is not popular is that, for example, as shown in FIG. Because of this, the structure is complicated, the number of parts is large, the processing cost is increased, and it will cause a failure in the future.

[0004] The only type of standard valve, the internal screw type valve rod non-elevating type, is not a single port, but an old standard twin port fire hydrant. This will be described with reference to FIGS. 5, 6 and 7. Is
A fluid inlet h is opened below, and a valve body insertion port i and a fluid outlet j are opened above.

A valve stem k is vertically attached to the valve box g from above through a valve body insertion opening i via a valve stem receiver m.
The valve body n is screwed forward. When the male screw o engraved on the valve stem k rotates in response to the rotation of the upper cap p, the guide q on the valve box g and the guide r on the valve body n engage as shown in FIG. By doing so, the valve element n is prevented from rotating, so that the valve element n moves up and down in relation to the non-rotatable valve element n and the valve rod k supported so as not to move up and down. It opens and closes.

At this time, the method of supporting the valve stem k is as follows.
The valve stem m is fitted into the valve body insertion opening i above the valve box g, and the valve stem k is placed on the valve stem receiver m, whereby the valve stem g is supported by the valve box g.

As described above, in the non-ascending valve stem type, as shown in FIG. 4, the valve stem and the valve element are screwed together with each other by screws. However, since there is no instability such as the valve body hanging at the tip of the valve stem, the water stopping performance is improved, and the valve suspension is not complicated (see FIG. 3A). On the other hand, there is a disadvantage that a valve stem receiver is always required, and therefore, a mounting seat for the valve stem receiver or an installation bolt is required.

[0008]

In the conventional structure, a valve stem support for supporting a valve stem is provided, and a valve body insertion member provided on an upper part of a valve body for inserting a valve body into a valve body. Since the inner diameter of the opening needs to be larger than the outer diameter of the valve, the valve box becomes large, and the number of parts and machining points increases, which complicates the structure and increases the cost. However, the present invention has been made to solve these problems.

[0009]

That is, according to the present invention, in an underground fire hydrant of an internally threaded valve stem non-elevating type, an opening is formed above a valve box to serve both as a valve element insertion port and a fluid outlet,
A valve stem insertion port is formed by integrally forming a valve stem support portion in a part of the opening.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the embodiment shown in FIGS. 1 and 2, FIG. 1 is a vertical sectional view of the whole, and FIG. 2 is a plan view of a valve box part. The valve box 1 of an underground fire hydrant has a fluid inlet 2 below and an opening 3 which serves both as a valve body insertion port and a fluid outlet above, and a projection 4 as a valve stem support is provided in a part of the opening 3. Thus, the valve stem insertion port 3A is formed. The projection 4 is integrally formed with the valve box 1 by, for example, integral casting.

The valve stem 5 has its flange 6 mounted on the projection 4, and a male screw 7 is engraved on a portion of the valve stem 5 below the projection 4. A valve body 9 provided with a female screw 8 screwed into the screw 7 is seated on a valve seat 10 formed in the valve box 1 and closes the fluid inlet 2.

On the other hand, a portion of the valve stem 5 above the flange 6 protrudes upward through a hollow cylinder 12 formed in a lid 11 connected to the valve box 1 and has a cap at its upper end. 13 is formed. In the hollow cylinder 12, a sealing means 14 is provided around the valve stem 5.

In the above configuration, when the cap 13 is rotated, the non-rotatable valve element 9 is moved up and down by rotating the male screw 7 of the valve stem 5, so that the valve is opened and closed accordingly. As the rotation preventing mechanism of the valve element 9, for example, the mechanism shown in FIG.

[0014]

According to the present invention, the number of parts and the number of processing steps can be reduced by integrally forming the valve box and the valve stem supporting portion (projecting portion). A fire hydrant can be realized.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view showing an embodiment of an underground fire hydrant of the present invention.

FIG. 2 is a plan view of a valve box part of the underground fire hydrant shown in FIG.

FIG. 3 is a vertical sectional view of a conventional product (a new standard fire hydrant (single port)).

FIG. 3A is an enlarged view of a valve hanging portion of FIG. 3;

FIG. 4 is a vertical sectional view of another example of a conventional product.

FIG. 5 is a further vertical sectional view of a conventional product.

FIG. 6 is a plan view of a valve box portion of the example shown in FIG.

FIG. 7 is an enlarged sectional view taken along line AA of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Valve box 3 Opening which doubles as a valve element insertion port and a fluid outlet 3A Valve rod insertion port 4 Projection (valve rod support part)

Continued on the front page (72) Inventor Toshinobu Iwasaki 4-16 Yasuyo-cho, Hikone City, Shiga Prefecture Inside Shimizu Iron Works

Claims (1)

[Claims] In an underground fire hydrant of an internally screw-type valve stem non-elevating type, an opening serving both as a valve body insertion port and a fluid outlet is formed above a valve box, and a valve stem supporting portion is integrated with a part of the opening. An underground fire hydrant formed by forming a valve stem insertion port.