JP3848735B2 - Manhole bottom plate in manhole pump system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a manhole bottom plate in a manhole pump system.
[0002]
[Prior art]
Conventionally, for example, in a sewerage facility, a manhole is provided in the middle of a sewage pipe, and sewage is temporarily stored in the manhole and then pumped up by a manhole pump (submersible motor pump) for delivery.
By the way, if the manhole bottom is flat, especially if there is no sewage inflow, there is a predetermined space between the manhole bottom and the pump suction port, so that foreign matter remains with the sewage at the bottom of the manhole, causing odors to occur. Become.
Therefore, conventionally, it has been proposed to devise a manhole bottom structure in Japanese Patent Laid-Open No. Hei 6-280299.
These are those embedded pre-rotation chamber is manhole bottom plate made of a synthetic resin plate by Concrete Da設both the manhole le bottom.
[0003]
In the manhole pump system, a detachable submersible motor pump has recently been applied as a pump.
As shown in FIG. 5, the detachable submersible motor pump P includes a submersible motor pump body Pa composed of a motor and a casing containing an impeller and the like, and a bend 14 installed at the bottom of the manhole M. The discharge side is connected to the pumping pipe 16.
Further, over the top of the manhole M from the fixed portion such as the bend 14 or manhole le bottom, placing the two guide members 19 such as a wire.
A hook portion 12 that engages with the inflow side flange 15 of the bend 14 is provided at the upper portion of the discharge side flange 11 of the submersible motor pump main body Pa , and the upper portion of the discharge side flange 11 has the 2 A holding portion 13 for holding the guide member 19 of the book is provided.
The submersible motor pump main body Pa is connected to a chain 17 that is pulled up by a hoisting device (not shown).
[0004]
Were it to Tsu, as shown in the figure, when the submersible motor pump body Pa the chain 17 suspended by the guide to the guide member 19, the hook portion 12 is engaged with the inlet side flange 15 of the bend 14, followed The horizontal distance between the center of gravity of the submersible motor pump main body Pa and the locking point a in the figure is the "arm length", and the discharge side flange of the submersible motor pump main body Pa by the moment with the weight of the submersible motor pump main body Pa as a load. 11 is pressure-bonded to the inflow side flange 15 of the bend 14, and the submersible motor pump P is in a state capable of pumping operation.
Further, Raising the chain 17, submersible motor pump body Pa by the operation and the reverse action because pulled on the ground, it is possible to easily perform the maintenance and the like of the submersible motor pump body P a on the ground. Reference numeral 18 denotes a power supply cable to the motor.
[0005]
[Problems to be solved by the invention]
However, the outer diameter of the pre-rotation tank shown in the Japanese Patent 6-280299 discloses such is minor than manhole inner diameter, and, after installation of the pre-rotation tank manhole bottom, because the concrete is pouring, pre-rotation chamber In the installation process, the pre-swirl tank tends to float from the concrete, so it is very difficult to install the pre-swivel tank, and many jigs etc. are used to prevent lifting, and workability is extremely poor. Has a problem.
It is an object of the present invention to provide a manhole bottom plate in a manhole pump system that can be very easily attached to the manhole bottom by modifying the shape of the manhole bottom plate.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, a manhole bottom plate made of a synthetic resin plate , a concrete mounting portion for mounting a pump with an opening side wall projecting downward, and at least one pump water-absorbing water retainer are provided. which has a recess, the outer peripheral portion, slightly larger outer diameter than the inner diameter of the manhole body portion, and an annular groove opening upward with slits at predetermined intervals, yet the water cut recess and concrete portion sidewalls The amount of downward protrusion is the same.
In the invention of claim 2, the manhole bottom plate is such that the upper surface is lowered in a bowl shape toward the water retaining recess.
According to a third aspect of the present invention, the manhole bottom plate is divided into a plurality of parts, and at least a part of the divided surface is provided with a joint extending vertically downward.
According to a fourth aspect of the present invention, the height of the joint portion is the same as that of the water retaining recess and the side wall of the concrete placing portion.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings.
As shown in FIGS. 1 and 2, the manhole bottom plate 1 in the manhole pump system according to the present invention has a disk shape whose outer diameter is slightly larger than the inner diameter of the bottom of the manhole main body to be installed. The two recessed portions 2 and 2 and the peripheral side wall 5 of the opening 4 are provided with a concrete placement portion 3 projecting downward, and an annular groove 6 opened upward is provided on the outer periphery of the bottom plate 1. Are provided with slits 7 at predetermined intervals. The manhole bottom plate 1 is integrally formed of synthetic resin, preferably glass fiber reinforced plastic (FRP). Moreover, the depth of the said water retention recessed part 2 and the concrete placement part 3 is the same.
[0008]
In the manhole M, the opening exposed to the ground surface is generally provided eccentrically with respect to the axis of the manhole, and the diameter thereof is smaller than that of the main body made of a straight cylinder .
Therefore, the manhole bottom plate 1 is installed immediately after the main body of the manhole M is completed.
That is, the outer diameter of the manhole bottom plate 1 is slightly larger than the inner diameter of the manhole main body, but the annular groove 6 is provided with a slit 7 and can be elastically deformed inward, so that the annular groove 6 faces upward. Then, the manhole bottom plate 1 can be pressed against the bottom of the manhole main body, and the lower end of the side wall 5 of the concrete placing portion 3 can be mounted in contact with the bottom.
[0009]
When the manhole bottom plate 1 is installed at the bottom of the manhole, an adhesive 8 such as silicon rubber is filled between the annular groove 6 and the side wall of the manhole body to prevent water leakage at this portion.
Thereafter, concrete is placed from the opening 4 of the concrete placing portion 3. Since the side wall 5 of the concrete placing part 3 is almost in contact with the bottom of the manhole, the concrete is placed only on the concrete placing part 3 and does not flow into other spaces.
In this way, after the manhole bottom plate 1 is installed at the bottom of the manhole, the manhole M is completed by integrating the remaining portion with the opening on the manhole main body , and then the bend 14 is attached to the concrete placing portion 3. In addition to being installed on the concrete , the guide member 16 is attached and the pumping pipe 16 is disposed. And the submersible motor pump main body Pa is installed and it is set as a manhole pump system. In this embodiment, the manhole pump P 2 Tai設 location, to position the suction port of the manhole pump P to MizuTome recess 2.
[0010]
Then, it is impossible to put the manhole bottom plate 1 from the manhole opening in the finished manhole M.
In this case, the manhole bottom plate 1 is divided.
FIG. 3 shows a two-divided structure. The manhole bottom plate 1 is divided so as to be bilaterally symmetric, and joints 9 and 9 made of joint plates extending vertically downward are integrally formed on a split surface excluding the concrete placing part 3. Is formed. And the height of the junction part 9 is made the same as the depth of the water retaining recess 2 and the concrete placing part 3.
[0011]
Therefore, an adhesive is applied to the facing surfaces of the joints 9, and first, the piece 1a of the manhole bottom plate 1 is suspended from the opening (not shown) into the manhole M and positioned at a predetermined position. Thereafter, the remaining piece 1b is suspended in the manhole M in the same manner, and the annular groove 6 is slidably contacted with the inner wall of the manhole M while the joint 9 is pressed against the joint 9 of the previous one piece 1a. The pieces 1a and 1b are positioned at predetermined positions. In this case, the water retaining recess 2, the concrete placing portion 3 and the joint portion 9 function as a kind of ribs, so that an operator can work on the manhole bottom plate 1 when joining the joint portions 9 and 9. it can.
Thereafter, as in the first embodiment, the adhesive 8 may be filled in the annular groove 6 and concrete may be placed from the concrete placing portion 3. In order to further strengthen the joining at the joining portion 9 , as shown in FIG. 4 , the joining portion 9 is also provided on the dividing surface (space) of the concrete placing portion 3 and this portion is interposed through the through hole 10. May be connected with bolts and nuts.
Needless to say, the method of attaching the bend 14 and the like is similar to that of the first embodiment.
Further, the manhole bottom plate 1 is not limited to two divisions, and may be three divisions.
[0012]
In the above description, the surface of the manhole bottom plate 1 has been described as being flush with the manhole. However, the manhole is inclined at least sequentially toward the water retaining recess 2, that is, in the form of a squirrel bowl so that sewage is guided to the water retaining recess 2. It is preferable to reduce the remaining amount of sewage at the bottom plate as much as possible.
Furthermore, in the description, since the manhole bottom plate 1 under the non-concrete structure 3 not Da設concrete, but the use of concrete also less expensive, the opening provided in the appropriate position of the manhole bottom plate 1, a concrete from which You may cast it. In this case, the manhole bottom plate 1 tends to float upward as the concrete is placed, but the outer end of the annular groove 6 acts like a so-called claw and does not have to worry about biting into the inner surface of the manhole M. .
[0013]
【The invention's effect】
As apparent from the above description, according to the invention of claim 1, the manhole bottom plate has slits at predetermined intervals on the outer periphery thereof, and is provided with an annular groove having an outer shape slightly larger than the inner diameter of the manhole opened upward. Therefore, it can be easily installed simply by pressing against the bottom of the manhole, and the amount of concrete used is low and inexpensive. Further, even when concrete is placed below the manhole bottom plate, it is not necessary to provide a complicated manhole bottom plate support member to prevent its lifting. Moreover, since the amount of protrusion of the bottom of the manhole bottom plate and the concrete placement portion are the same, if these are placed on the bottom of the manhole, this portion is reinforced, so that the top of the manhole bottom plate Workers can get on and work, improving workability.
According to the invention of claim 2, since the upper surface of the manhole bottom plate is lowered toward the water retaining recess, most of the sewage can be sucked and generation of off-flavor can be suppressed.
According to the invention of claim 3 , since the manhole bottom plate is divided, the manhole bottom plate can be inserted from a relatively small upper opening of the completed manhole, and further has a joining portion extending vertically downward on the dividing surface. It becomes a guide for time and joining work is easy. Further, by using this joint portion, it is possible to easily and reliably bond and integrate, and the workability is very good.
According to invention of Claim 4 , since the height of the joint part of a manhole bottom plate, a water retention recessed part, and a concrete placement part is the same, the effect of Claim 1 can further be improved.
[Brief description of the drawings]
1A is a plan view showing a first embodiment of the present invention, FIG. 1B is a cross-sectional view taken along the line II-II of FIG. 1A, and FIG.
FIG. 2 is an enlarged cross-sectional view of an annular recess in FIG.
FIG. 3 is a perspective view showing a second embodiment of the present invention, half of which is a perspective view from the bottom side.
FIG. 4 is a perspective view showing a third aspect of the present invention, half of which is a perspective view from the bottom side.
FIG. 5 shows the installation method of the submersible motor pump, where (A) shows before installation and (B) shows after installation.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Manhole bottom plate, 2 ... Water retaining recessed part, 3 ... Concrete placement part, 5 ... Side wall, 6 ... Annular groove, 7 ... Slit, 8 ... Adhesive, 9 ... Joint part.

Claims (4)

It has a concrete mounting portion for mounting the pump that projects downward from the opening side wall and at least one water retention recess for pump water absorption. A manhole bottom plate in a manhole pump system comprising a synthetic resin plate having an annular groove having an upward opening having a slit, and having the same amount of protrusion downward from the water retaining recess and the side wall of the concrete placing portion .   The manhole bottom plate in the manhole pump system according to claim 1, wherein an upper surface of the manhole pump system according to claim 1 is lowered in a bowl shape toward the water retaining recess. The manhole bottom plate in the manhole pump system according to any one of claims 1 and 2 , wherein the manhole bottom plate is divided into a plurality of portions, and a joint portion extending vertically downward is provided on at least a part of the dividing surface. The manhole bottom plate in the manhole pump system according to claim 3 , wherein a height of the joint portion is the same height as the water retaining recess and the side wall of the concrete placing portion.

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