JPH0340954Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a backflow prevention device installed at the outlet of a large discharge ditch for sewage, etc. to a river, or the outlet of a large branch pipe to a drainage ditch main pipe.

[Conventional technology]

Recently, sewage facilities have been improved, but during torrential rains, the water level in rivers suddenly increases, backing up through large drainage ditches such as sewage mains, pushing up the iron covers of manholes, and overflowing onto the streets. Not only do they obstruct traffic, but they also cause flooding damage to nearby houses. To solve this problem, a lid-shaped valve body that can be opened and closed to prevent backflow can be installed near the outlet of the large drainage ditch. In other words, when draining water, the valve body is opened by the drainage water pressure, and when the water rises, the pressure of the increased water pushes the valve body against the outlet of the large drain, blocking the large drain and preventing water from flowing back. There is.

[The problem that the idea aims to solve]

Since such a discharge groove generally has a large diameter, the valve body that closes it must also be large. At this time, if the valve body is made of a heavy material such as metal, the heavy valve body cannot be opened due to the low drainage water pressure when the drainage volume is small, and the wastewater is not discharged smoothly and flows into the drain. There is a risk that it will stop. Furthermore, if the valve body, mounting body, and hinge portion are made of plastic, they are likely to crack or break and lack durability. Furthermore, such backflow prevention devices are constantly exposed to drainage or wind and rain, so they are left semi-permanently in conditions where rust is likely to occur.
When rust occurs, frictional resistance at the hinge increases, which not only prevents smooth opening and closing of the valve body and prevents drainage, but also causes problems such as the inability to prevent backflow when water increases. In order to prevent such problems, valve bodies must be frequently maintained and inspected, but due to the public nature of sewage facilities, the burden of such maintenance and management costs is borne by users.

Therefore, in view of the above problems, the purpose of the present invention is to:
Drains water smoothly and reliably even when the amount of water discharged is small.
It reliably prevents water from flowing back into large drainage ditches when river water levels rise, and by permanently and smoothly draining water, maintenance and inspection work for this backflow prevention device can be omitted, and the user of the sewage facility can An object of the present invention is to provide a backflow prevention device for use in large drainage ditches such as sewage, which reduces the burden.

[Means to solve the problem]

In order to achieve the above object, the present invention includes a cylindrical mounting body whose rear opening surface is attached to the outlet opening surface of a large drainage ditch such as sewage, and a cylindrical mounting body whose rear opening surface is attached to the outlet opening surface of a large drainage ditch such as sewage, and whose upper part is attached to the front opening surface of the mounting body to open and close it. In the backflow prevention device for drains such as sewage, which comprises a valve body pivotally connected to the upper part of the mounting body via a hinge, the valve body is made of glass fiber reinforced plastic, and the upper and lower parts are
In addition to being structured in parts, the entire body is supported via a hinge at the top of the front opening of the mounting body so that it can be opened and closed.
Moreover, the lower half part is supported by the upper half part via a hinge so that it can be opened and closed independently, and the mounting body and the hinge part are made of rust-resistant metal,
Furthermore, the front opening surface of the mounting body is characterized in that the lower part of the opening surface is a sloped surface located forward of the upper part of the opening surface.

[Effect]

This invention uses lightweight glass fiber reinforced plastic (hereinafter referred to as G-FRP) for the valve body that opens and closes the large drainage ditch, and further divides the valve body into upper and lower parts so that the upper and lower parts can be opened and closed together, or only the lower part can be opened and closed. It has a structure that allows it to operate. As a result, when the displacement is small, only the lower valve body performs the opening operation, and when the displacement is large, the upper and lower valve bodies together perform the opening operation. In particular, when the displacement is small, only the lower valve element of the lightweight G-FRP valve element opens independently, so even if the valve element is large enough to fit a large drainage ditch, it will not be possible to open it. The required drainage water pressure is reduced to less than half, so drainage can be carried out smoothly and reliably even when the amount of drainage is small. In addition, since G-FRP is a material that maintains high rigidity, the valve body will not be destroyed by the water pressure of the increased water even when the river water increases. By forming the slope so that the front opening of the mounting body is located at the front, the front opening of the mounting body can be reliably closed by the valve body's own weight, and the water pressure of the increased water is reduced between the valve body and the mounting body. For stronger adhesion,
From the above points, it is possible to reliably prevent water from flowing back into the large drainage ditch when the water rises. In addition, since the parts of this backflow prevention device other than the valve body are made of non-rust metal, cracking of the mounting body and damage to the hinge part can be prevented, and the entire backflow device including the valve body made of G-FRP can be prevented. This means that corrosion resistance has been achieved, and as a result, rust is prevented from forming and permanent and smooth opening/closing operation of the valve body is achieved.

〔Example〕

Embodiments of the present invention are shown in FIGS. 1 to 3.

Reference numeral 1 denotes a cylindrical mounting body having a rectangular cross section at the upper part and a semicircular cross section at the lower part;
The front opening surface is inclined by an angle α such that the lower part is located forward than the upper part, has a mounting flange 1a at the rear part, has a flange-shaped valve seat part 1b integrally at the front part, and has appropriate ribs 1c around the periphery. All of these are made of rust-free metal materials such as stainless steel. Reference numeral 2 denotes a valve body made of G-FRP having an area capable of closing the front opening surface A of the mounting body 1, and the valve body 2 is divided into an upper valve body 2a and a lower valve body 2b. has been done. At this time, the mounting body 1
It is also possible to form G-FRP in the same way as the valve body 2, but in this case, there is a risk that the cylindrical G-FRP mounting body 1 may crack due to the drainage water flow, so this invention is not suitable. In this case, the mounting body 1 is made of a rust-proof metal such as stainless steel.

On the back side of the upper valve body 2, there is a 2 plate having a U-shaped cross section.
The longitudinal reinforcements 3, 3 of the book are bolted together at several points, the lateral supplementary material 4 is similarly bolted to the lower edge, and the handle 5 is laterally attached. Also, on the back surface of the lower valve body 2b, two vertical reinforcing members 6, 6 having a U-shaped cross section are bolted to the reinforcing members 3, 3 at several points in a straight line, and the handle 7 is attached horizontally. installed in the direction. The upper valve body 2a is pivotally attached to the upper hinges 8, 8 of the mounting body 1 via hinge pins 9, 9 using the upper ends of the two vertical reinforcing members 3, 3,
Further, the lower valve body 2b includes two longitudinal reinforcing members 6,
The upper end of the upper valve body 2a is pivotally connected to the horizontal reinforcing member 4 at the lower edge of the upper valve body 2a via hinges 10, 10. The reinforcing members 3, 4, 6, the handles 5, 7, the hinge pin 9, and the hinges 8, 10 described above are all made of rust-proof metal such as stainless steel. With the above configuration, only the lower valve body 2b opens smoothly when the displacement is small, and the upper and lower valve bodies 2b operate smoothly when the displacement is large.
a and 2a integrally perform the opening operation.

A packing 11 made of neoprene rubber or the like is adhesively fixed around the rear surface of the mounting flange 1a at the rear of the mounting body 1, and mounting bolt holes 12 are formed at multiple locations around the mounting flange 1a to connect the large drainage groove outlet or drainage. It is to be attached via anchor bolts (not shown) to large branch pipe outlets (neither shown) to the trench main. This anchor bolt is also made of a rust-free metal material such as stainless steel. Also, the flange-shaped valve seat portion 1b at the front of the mounting body 1
A packing 13 made of neoprene rubber or the like is similarly adhesively fixed around the rear surface. This pack king 1
3, and the slope α formed on the front opening surface of the mounting body 1 improves the sealing performance when the valve body 2 contacts the valve seat portion 1b of the mounting body 1 when there is no drainage, and also improves the sealing performance of the river. To further strengthen the close contact between a valve body 2 and a mounting body 1 when water increases, and to surely prevent water from flowing back into a large drainage ditch.

[Effect of idea]

In the present invention, the valve body is made of lightweight G-FRP and is divided into upper and lower halves, making it possible to perform the opening operation using only the upper and lower valve bodies or the lower valve body alone. Therefore, even at low drainage water pressure, only the lower valve element can be easily opened, and smooth and reliable drainage can be achieved even when the amount of drainage is small. In addition, since G-FRP is a material that maintains high rigidity, it will not be destroyed by the water pressure of the increased water even when the river water increases.
Furthermore, by forming an inclination α on the front part of the mounting body, the water pressure of the increased water will make the valve body and the front of the mounting body more tightly attached, thus preventing water from flowing back into the large drain when the water rises. definitely prevent it. In addition, since the parts other than the valve body are made of rust-resistant metal, the entire backflow prevention device is corrosion resistant, preventing rust and ensuring permanent and smooth opening and closing of the valve body. . As a result, it is possible to omit maintenance and inspection work for this backflow prevention device, reduce maintenance costs for sewerage facilities, and reduce the burden on users.

[Brief explanation of the drawing]

FIG. 1 is a front view of the device of the present invention, FIG. 2 is a rear view of the entire device, and FIG. 3 is a sectional view taken along line A--A in FIG. 1... Mounting body, 2... Valve body, 2a... Upper valve body, 2b... Lower valve body, 8... Hinge.

Claims (1)

[Scope of utility model registration request] A cylindrical mounting body whose rear opening surface is attached to the outlet opening surface of a large drainage ditch such as sewage, and the upper part of which is attached to the top of the mounting body via a hinge so as to open and close the front opening surface of this mounting body. In the backflow prevention device for drains such as sewage, which is equipped with a pivotally connected valve body, the valve body is made of glass fiber reinforced plastic,
In addition, it is configured to be divided into upper and lower halves, and the entire body is supported so as to be openable and closable via a hinge at the upper part of the front opening surface of the mounting body, and the lower half part is independently separated from the upper half part via the hinge. Supported so that it can be opened and closed,
Further, the sewage system is characterized in that the mounting body and the hinge portion are made of rust-resistant metal, and the front opening surface of the mounting body is a slope with the lower part of the opening surface located forward of the upper part of the opening surface. Backflow prevention device for large drainage ditches such as.