JPS60215928A - Preventor for inflow of rain water for cover of underground structure - Google Patents

Abstract

PURPOSE:To permit the ventilation of air all the time while preventing the intrusion of rain water into an underground structure during the abnormally heavy rain period by a method in which a rain intrusion preventing valve is provided to the back side of a cover with a through hole, and the valve is designed to be closed by the weight of a rain water absorptive material during the rain period but to be opened during the usual period. CONSTITUTION:A through hole 4 is provided in the cover 1 of an underground structure such as a manhole, etc., and a rain water intrusion preventing valve A is provided to the back side of the cover 1. The valve A consists of a case, a valve shaft 18, a valve body 19, a spring 17 to physically energize the body 19, and a water absorptive material 22. The valve case has an opening 13 connecting the hole 4 with the inside of the underground structure, and the valve shaft 18 is inserted into the opening 13 in a vertically movable manner. The valve body 19 is attached to the upside of the shaft 18, and the water absorptive material 22 is integrally connected with the lower part of the shaft 18 and plural through holes 23 are vertically provided in the material 22. The intrusion of rain water into the underground structure during the abnormally heavy rain period can thus be exactly prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rainwater inflow prevention device for a cover for an underground structure that closes a manhole or the like.

[Prior art and its problems]

Conventionally, there is a device described in Japanese Patent Publication No. 513-15569 as a rainwater inflow prevention device for a manhole cover or the like. As shown in Fig. 1, this is done through a communication hole (10
1) is installed through the hole (101), and rainwater flows through this hole (101) when it rains.
A float valve (102) is arranged to prevent water from flowing down into the underground structure.

The float valve (102) is supported by a mounting plate (103) connected to the back surface of the lid (100) and has a hole (104) at its lower end.
a) is housed in the float chamber (104), and the mounting plate (103) has a window (105) for draining rainwater and sediment.
has been established. The lower end of the float valve (102) is recessed with a ball valve storage chamber (107) having a sloped surface (106), and a pole valve (108) is installed in the same chamber. 108) The mounting plate (103) corresponding to the mounting position has a drainage hole (
109) has been established.

In the above configuration, under normal conditions, the float valve (102') descends due to its own weight to maintain ventilation between the outside of the lid and the inside of the lid (100) through the communication hole (101), and to release harmful gases from inside the vertical hole. is released, and furthermore, abnormal lift pressure is prevented.

On the other hand, during rainfall, rainwater flows into the float chamber ('104) from the communication hole (101), and this inflow water flows through the hole (104).
a) and is discharged from the drainage hole (109).

However, when the inflow becomes larger than the outflow from the hole (104a), the float valve (102) rises and the ball valve (10
8) is the inclined surface (106) in the ball valve accommodation chamber (107)
The locking force caused by
104a) to close the opening (104a). In this state, the float valve (102) rises rapidly, and the inclined wall (102a) of the float valve (102)
1) can be closed to prevent rainwater from flowing in.

However, since the volume of the float valve (102) is constant, there is an upper limit to the buoyant force exerted by the accumulated water in the float chamber (104). During floods, the water level is lower than the lid (100)
Since the float valve (102) is located higher up, as the water level rises, the float valve (102) receives a downward force based on the water pressure caused by the increase in water. This downward force acts on the float valve (
If the buoyancy force is greater than the buoyancy force exerted by the float valve (102), there is a problem in that the float valve (102) is unable to descend and close the opening (101a).

[Purpose of the invention]

An object of the present invention is to eliminate the above-mentioned drawbacks, and to provide a device that can reliably prevent large amounts of rainwater from flowing in during abnormal rainfall.

[Structure of the invention]

The structure of the present invention is that a through hole (4) is provided through the lid (11) and a rainwater inflow prevention valve (A) is provided on the back surface of the lid.
The rainwater inflow prevention valve (A) is an opening (A) attached to the back of the lid (11) that communicates the through hole (4) with the inside of the underground structure.
13) with valve case 00) and the same valve case (10)
A valve shaft (18) is supported so as to be movable up and down and inserted through the opening (13). A valve body (19) that approaches and separates, a spring (17) that biases the valve shaft (18) in the valve opening direction, and a spring (17) located on the lower side of the opening (13) and integrally connected to the valve shaft (18). The water absorbent body (22) has a plurality of holes (23) in the vertical direction.
It is constructed by penetrating the

〔Example〕

The present invention will be described below based on embodiments shown in the drawings.

FIGS. 2 and 3 are a front and back plan view of a manhole cover used as a cover for underground structures. In the figure, (11 is a lid body in which a hinge mounting part (2) and a pearl hole (3) are formed facing each other in the diametrical direction, and through holes (11) are located at four positions on a concentric circle to communicate the inside of the manhole vertical hole with the outside. 4
) is installed throughout.

FIG. 4 is an enlarged sectional view taken along the line 1-1 in FIG. The valve chamber (7) has a cylindrical shape. The lower end of the valve chamber (7) is open, and the cylindrical wall (6) has a vent hole (8) and a mounting hole (to be described later) for mounting the valve case. 9) respectively.

The through hole (4) is divided into three sub-arc shapes formed on a concentric circle, and has a central portion (4a) and a connecting portion (4b).

Figure 5 is a sectional view when the valve case 00) is installed in the valve chamber (7) to form a rainwater inflow prevention valve (A), and Figure 6 is an exploded view of each component of the prevention valve (A). FIG.

The valve case 00) is made of elastic synthetic resin, and has a cylindrical part (11) with openings at both upper and lower ends on the upper side.
) forming three legs (12) extending downwardly. The inside of the cylindrical part (11) has a steeply sloped forest-like cross section with a diameter decreasing at the lower end, and an opening (13) at the lower end allows communication between the inside and outside of the man-ball, and the mortar-shaped surface is a valve seat (14) for a valve body (described later).
). The lower end of the leg (12) has an engagement piece (1) extending in the radial direction and bent downward from the extended end.
5) is formed, and when installed in the valve chamber (7), this retaining piece (I5) is inserted into the installation port (9) and engaged with the lower edge (9a) of the installation port (9). It is possible to fix the

(16) is a suspension frame whose base end is fixed to a recess (lla) formed in the cylindrical part (]1) for suspending a valve stem, etc., and the suspension frame (16) has a tension Spring (1
7) are connected in a hanging manner. (18) is a valve shaft that is inserted through the opening (13), and a synthetic rubber pankin (19) such as silicone rubber that constitutes the valve body is attached to the screw rod (21a) of the support plate (21) with a nut (20) at the upper end. It's stuck. This support plate (21) is hung by a spring (17), and the valve shaft (18) is connected to the suspension frame (16) so as to be movable up and down. The valve stem (18) is composed of three struts (18a) and a flange portion (18b) at the lower end.
b) is provided with a cutout opening (18c).

Furthermore, (22) is a sponge-like synthetic resin water absorbent that can be impregnated with water. In this example, it is made of polyvinyl alcohol resin and is formed into an annular shape. 18b) and integrated with the valve stem (18). This water absorbent body (22) has a large number of holes (23) vertically extending through it to increase the surface area of the water absorbent body (22) and promote evaporation of impregnated water.

In addition, (24) is a cover made of synthetic resin etc. that is removably attached to the lower end of the valve chamber (7), and has a large number of through holes (2
5) has been established.

To install the above components into the valve chamber (7), insert the valve case 011) from the lower end side of the valve chamber (7), and use elastic deformation to attach the engaging piece (15) of the leg (12). Attachment port (9)
By fitting into the valve case 00), the lower end of the valve case 00) can be locked and fixed. In addition, in Fig. 5, (26)
is a sealing material located on the outer periphery of the upper end of the valve case (GO), and in this example is made of a foamable resin that expands when impregnated with water. Therefore, after the valve case α0) is installed, this sealing material (26) expands when it contains water and becomes adhered to the inner wall of the valve chamber (7), fixing the valve case 00) and fixing the through hole (4). ) to the valve chamber (7
) Rainwater that tries to flow in through the inner walls can be blocked.

As a result of the above, a rainwater inflow prevention valve (A>) is formed on the back surface of the lid body (1), and under normal conditions it is in the state shown in Figure 5, that is, the packing (19) is separated from the valve seat surface (14) and the manhole is closed. Inside and outside are the through hole (4) and the opening (1) of the rainwater inflow prevention valve (A).
3) and a space formed between the three pillars (18a) of the valve stem (18). The spring (17) supports elements such as the valve stem 18) and the water absorbing body (22) by its tensile force, and when the water absorbing body (22) is not impregnated with water, it lifts the valve stem (18). The spring constant is set such that the valve can maintain the open state shown in the figure.

In Figure 5, since the inside of the man-ball is in communication with the outside world, air can circulate between the atmosphere and the inside of the man-ball, and harmful gases generated inside the man-ball can be released to the outside. Abnormal pressure rise of fluid such as air due to rise in the water level inside the pole can be prevented.

On the other hand, during rain, rainwater flows into the valve chamber (7) from the through hole (4), and the opening (1) of the rainwater inflow prevention valve (A) which is open.
3) flows down into the manhole, but at this time, the water absorbent body (22) is impregnated with rainwater by the flowing sewage, and the weight of the water absorbent body (22) increases by the amount of impregnation compared to normal. In addition to the spring constant condition of the spring (17) mentioned above, if the spring constant is such that the spring (17) starts to expand when the weight of the water absorbent body (22) due to water impregnation exceeds a certain critical point, then The valve stem (18) descends due to the increased weight. As a result, the gasket (19) is seated on the valve seat surface (14) in the cylindrical portion (If), and the rainwater inflow prevention valve (A) is closed, as shown by the dashed line in FIG. It is possible to prevent the influx of

In addition, even if the lid body (1) is submerged in water and water pressure is applied,
Since this water pressure acts in the direction of closing the valve, the valve will not open, completely preventing rainwater from entering.

Next, if the rain is interrupted or stopped, the moisture impregnated in the water absorbent body (22) is dried and removed by the outside air, and the water absorbent body (22) is dried and removed.
) The weight becomes lighter than normal, and the spring (
The restoring force of 17) causes the valve stem (18) to rise and open the valve, allowing ventilation to occur through the through hole (4) and opening (13).

In this way, the valve shaft (18) moves up and down in response to changes in the weight of the water absorber (22) due to moisture impregnation and dry discharge of the water absorber (22), thereby automatically opening and closing the rainwater inflow prevention valve (A). I can do it. In addition, since the water absorbent body (22) in the present invention has a large number of holes (23) to increase the surface area of the water absorbent body (22), the time required for moisture impregnation and drying and drainage can be shortened. It is possible to improve responsiveness to changes in the external world. Therefore, it is possible to reduce the burden on the sewage treatment capacity within the underground structure and at the treatment facility.

Furthermore, since the inside of the cylindrical part (11) of the valve case 0Φ has a steep slope like a forest, dirt, etc. that enter through the through hole (4) can be easily discharged from the opening (13), and rainwater can flow in. The prevention valve (A) does not become clogged and always functions well, and the frequency of maintenance and inspection can be reduced.

FIG. 7 is a sectional view showing another example of the rainwater inflow prevention valve (A>), in which the structure of the valve case 0ff and cover (24) is different from the previous example.

Figure 8 is a perspective view of the valve case αψ and the leg part (12) of the previous example.
While extending downward the three mounting leg pieces (50) corresponding to , a hanging wall (
51), and a plurality of slits (52) are opened in the vertical direction in this hanging wall (51). Mounting leg piece (50)
A swelling part (53) protruding outward is formed at the lower end of the
Like the engaging piece (15) in the previous example, it can be fitted into the mounting opening (9) of the cylindrical wall (6) by utilizing elastic deformation.

In this example, the cover (24) is fixed to the lower end of the valve case (101) with adhesive, and can be used as a valve unit in which valve components are enclosed within the valve case (101) and the cover (24). , it can be easily installed into the cylindrical wall (6).

The other configuration is exactly the same as the previous example, but in this example, a hanging wall (51) is provided, so the valve components are not exposed from the mounting port (9), and the intrusion of foreign objects can be prevented. This allows for smooth operation. Furthermore, since the slit (52) is provided, ventilation can be carried out without any problem when the valve is opened.

Although the above embodiments have been described with respect to manhole covers, it goes without saying that the present invention can be applied to covers for other underground structures.

〔effect〕

The effects of the present invention are listed below.

1) When rainwater flows in, the valve can be automatically closed due to the increased weight of the water absorption body, preventing large amounts of water from flowing into underground structures, thereby improving sewage treatment in underground structures and treatment facilities. The burden on ability can be reduced.

(2) Even if water accumulates on the top surface of the lid and water pressure is applied, this water pressure acts on the rainwater inflow prevention valve in the direction of closing the valve, so the valve will not open, and rainwater inflow can be reliably prevented.

(3) Since the valve body moves up and down based on the increase/decrease in weight due to the water absorbing body, communication between the outside air and the inside of the underground structure can be automatically established and disconnected.

(4) After the rain has stopped, the valve body will automatically return to its original position as the water absorbent dries, allowing ventilation between the outside world and the inside of the underground structure, and further reducing air, etc. inside the underground structure. The compressed fluid can be discharged to the outside world.

(5) The water absorbing body has multiple holes and a large surface area, so rainwater can be impregnated and dried quickly, and the valve body can be opened and closed in response to changes in the outside world. .

(6) The inside of the cylindrical part of the valve case has a steep slope like a forest, and the opening at the bottom is wider than the hole on the lid, so all the dirt, etc. that enters through the hole on the lid will be removed. It can be discharged into underground structures.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the main parts of a conventional rainwater inflow prevention device, Fig. 2 is a top view of the manhole cover, and Fig. 3 is a back plan view of the manhole cover.
4 is a sectional view taken along the line I-I in FIG. 2, FIG. 5 is a sectional view showing the rainwater inflow prevention valve, FIG. 6 is an exploded perspective view showing each component of the prevention valve, and This figure is a sectional view showing another structure of the rainwater inflow prevention valve, and FIG. 8 is a perspective view of the valve case in FIG. 7. 111 M body (4) Through hole α [valve case (13) Opening (17) Spring (18) Valve shaft (19) Packing (valve body) (22) Water absorbing body (23) hole (A) Rainwater inflow prevention valve patent Applicant Nissho Kosan Co., Ltd. Agent Masu Tegori (and 1 other person) Figure 3 r Figure 5 ZOii! ! 5

Claims (1)

[Claims] 1. A through hole (4) is provided through the M body (1), and a rainwater inflow prevention valve (A) is provided on the back side of the lid body (11). 1) An opening (13) attached to the back surface that communicates the through hole (4) with the inside of the underground structure.
) and a valve shaft (18
) and the valve shaft (1) located above the opening (13).
A valve body (19) attached to the opening (13) and moving toward and away from the periphery of the opening (13), a spring (17) that biases the valve shaft (18) in the valve opening direction, and a lower part of the opening (13). It has a water absorbing body (22) located on the side and integrally connected to the valve stem (18),
This rainwater inflow prevention device for a cover for an underground structure is characterized in that the water absorbing body (22) has a plurality of holes (23) vertically extending through it.