JPH09100559A - Liquid storage tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide convenient liquid storage tanks with small installation area as compared with the big capacity thereof. SOLUTION: Storage tanks 2 and 2 buried in the ground are connected to each other with a siphon pipe 4. An air vent valve 6 is provided at the center of a horizontal pipe section 4b as the highest position of the siphon pipe 4. Opening and closing operation of the air vent valve 6 can be made from the ground. The upper parts between the storage tanks 2 and 2 are connected with a connection pipe 7. The connection pipe 7 is located at a position higher than the horizontal pipe section 4b. A supply pipe 8 for supplying water is connected to the storage tanks 2. The supply pipe 8 is connected to a neighborhood water catchment basin. Water is led into the storage tanks 2 through the supply pipe 8, and the water level of the storage tanks 2 connected with the connection pipe 7 is set in a higher position than the horizontal pipe section 4b of the siphon pipe 4. The air vent valve 6 is opened to make air vent from the siphon pipe 4. Water can be supplied from one storage tank 2 to the other storage tank 2 through the siphon pipe 4. The water level of the storage tanks 2 connected with the siphon pipe 4 rises and falls in a constant state with the water supply or the pumping-up of water from the storage tanks 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid storage tank in which a plurality of storage tanks buried underground are connected by a siphon pipe. The storage tank of the present invention can be applied to storage of rainwater, spring water, industrial water, disaster prevention water, drinking water, and other liquids.

[0002]

2. Description of the Related Art For the purpose of irrigation, washing, disaster prevention, etc., a liquid storage tank for collecting and storing rainwater and spring water is used. As this type of liquid storage tank, a large-capacity box-shaped water tank constructed by pouring concrete into a hole excavated from the ground surface is known. However, the lesson of the Great Hanshin Earthquake was
Cracks are likely to occur in large concrete structures built underground, indicating that they are not necessarily suitable for emergency water storage.

[0003] At present, precast box-type water tanks of prefabricated type have become widespread. In order to carry out large-scale storage in this box-shaped water tank, a plurality of the box-shaped water tanks may be connected by a connecting pipe to form an aggregate of water tanks capable of storing a large amount.

[0004]

Although the precast prefabricated box-type aquarium has an earthquake-resistant structure, there is no guarantee that it will be complete against a large earthquake. In addition, if a plurality of the box-shaped water tanks are connected by a connecting pipe for large storage, a large area for arranging a large number of the box-shaped water tanks is required, and a place for installation is found in a city. There is an inconvenience. In addition, it is necessary to install a communication pipe near the bottom of the box-shaped water tank in order to distribute liquid such as stored water between adjacent box-shaped water tanks. There was concern that the impact would be so great that accidents such as water leaks would easily occur.

According to the present invention, in a liquid storage tank formed by connecting a plurality of storage tanks, adjacent storage tanks can be connected at a position close to the surface of the ground, the strength of each storage tank is high, and the size of the storage tank is small. It is an object of the present invention to provide a highly convenient liquid storage tank having a small installation area.

[0006]

According to a first aspect of the present invention, there is provided a liquid storage tank in which a plurality of storage tanks buried in the ground are connected by a siphon pipe.

According to a second aspect of the present invention, there is provided the liquid storage tank according to the first aspect, further comprising air venting means for venting air inside the siphon pipe.

According to a third aspect of the present invention, there is provided a liquid storage tank according to the second aspect, wherein the liquid storage tank is formed in the ground and collects surface water, and the bottom of the water collection tank extends into the ground. It has a plurality of storage tanks whose upper ends that are buried and opened are lower than the highest water level of the water collecting basin, and the highest point of the siphon pipe is lower than the highest water level of the water collecting basin. Characterize.

The liquid storage tank according to a fourth aspect is the liquid storage tank according to the third aspect, characterized in that the storage tank and the storage tank are communicated with each other by a connecting pipe inside the water collecting basin.

The liquid storage tank according to a fifth aspect is the liquid storage tank according to the second aspect, which has a water level higher than the highest point of the siphon pipe, and a communication pipe communicating the storage tank and the storage tank, A supply pipe for supplying a liquid to at least a part of the storage tank.

The liquid storage tank according to a sixth aspect is the liquid storage tank according to the fifth aspect, wherein an air vent valve is provided as the air vent means at the highest point of the siphon pipe, and the siphon pipe is passed through the inside of the communication pipe. At the same time, the communication pipe is provided with an operation hole for operating the air vent valve.

According to a seventh aspect of the present invention, in the liquid storage tank according to the first aspect, when the amount of the liquid stored in each of the storage tanks decreases, the respective storage tanks are lifted from the ground by buoyancy received from the ground. It is characterized in that a fixing means for fixing each storage tank to the ground is provided in order to prevent the occurrence of the above.

According to an eighth aspect of the present invention, there is provided the liquid storage tank according to the seventh aspect, wherein the fixing means is a locking portion projecting from the bottom of each storage tank.

The liquid storage tank described in claim 9 is characterized in that, in the liquid storage tank described in claim 7, the fixing means is a packed layer provided between each storage tank and the ground.

According to a tenth aspect of the present invention, there is provided the liquid storage tank according to the first aspect, wherein each of the storage tanks has a vertically long cylindrical shape having a height larger than a diameter.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The liquid storage tank of the present invention is one in which a plurality of storage tanks buried underground are connected by a siphon pipe. A first embodiment of the present invention will be described with reference to FIGS. The liquid storage tank 1 of this example is a facility that is installed in a residential area or the like and stores rainwater on the premises, and is used to store a relatively small amount of water. In this example, a hollow concrete cylinder is used as the storage tank. As shown in FIG. 1, a plurality of storage tanks 2 which are hollow cylinders made of concrete are provided.
Is buried underground. Each storage tank 2 has a lower end in the ground which is closed in advance, and an open upper end located on the ground surface is closed by a lid 3 which can be opened and closed. Also, asphalt or the like is applied to the entire inner surface of each storage tank 2 to form a water-impermeable film, so that even if a crack occurs in the storage tank 2 due to vibration such as an earthquake, the stored water is not easily lost. Good.

The adjacent storage tank 2 and the storage tank 2 are siphon pipes 4.
Is communicated with. The siphon pipe 4 is a curved pipe used to raise the liquid once to a high place and transfer it to a low place. The siphon tube 4 of the present embodiment has an inverted U-shape, and a pair of vertical tube portions 4a, 4a forming both ends thereof are arranged inside two adjacent storage tanks 2, 2, respectively, and a horizontal tube located at the highest point in the center is provided. The portion 4b penetrates the peripheral wall at the upper end of each storage tank 2. The open lower end of the vertical pipe portion 4a of the siphon pipe 4 is set near the bottom plate of the storage tank 2 with a predetermined space. The interval is set such that the open lower end of the siphon pipe 4 is not easily closed even when foreign matter is accumulated on the bottom of the storage tank 2 due to long-term use.

As shown in FIG. 2, the siphon tube 4 is fixed at the above-mentioned position by a mounting means 5 fixed to the inner peripheral wall of the storage tank 2. The mounting means 5 fixes an annular portion 5a fixed to the inner peripheral wall of the storage tank 2, a pair of grip portions 5b, 5b formed integrally with the annular portion 5a, and the grip portion holding the siphon tube 4. It has bolts and nuts 5c as fixing means. Since the siphon tube 4 is fixed by the attachment means 5, it does not move even when the water level in the storage tank 2 moves up and down. For example, when the storage tank 2 is a steel pipe, the holding portion 5 is provided on the inner peripheral surface of the storage tank 2.
b may be directly fixed.

As shown in FIG. 1, an air vent valve 6 as an air vent means is provided at the center of the horizontal pipe portion 4b, which is the highest point of the siphon pipe 4. The air inside the siphon tube 4 is evacuated by using the air bleed valve 6,
By filling the inside of the siphon tube 4 with a liquid, the siphon tube 4 will exhibit a siphon function. The air release valve 6 can be opened and closed from the ground surface.

A communication pipe 7 communicates between the adjacent storage tanks 2 and the upper portions of the storage tanks 2 so that air can be easily removed from the inside of the siphon pipe 4 and air is less likely to enter the siphon pipe 4. The connecting pipe 7 is located at a position higher than the horizontal pipe section 4b which is the highest point of the siphon pipe 4.

At least a part of the plurality of storage tanks 2 is provided at the same height as the connecting pipe 7 or at a position higher than that.
A supply pipe 8 for supplying water into the storage tank 2 is in communication. The supply pipe 8 communicates with a water collecting basin (not shown) installed in the vicinity. The catch basin is a storage space built near the ground surface to collect rainwater and the like flowing on the ground surface.

In order to use this liquid storage tank 1, first, water is introduced from the supply pipe 8 into the storage tank 2, and the water level of all the storage tanks 2 is set to a position higher than the horizontal pipe portion 4b of the siphon pipe 4. Since each storage tank 2 is communicated by the connecting pipe 7 at a position higher than the horizontal pipe section 4b of the siphon pipe 4, the supply pipe 8
If water is supplied to a specific storage tank 2 to which is connected,
Since the water that has reached the predetermined water level in the storage tank 2 overflows from the connecting pipe 7 to the adjacent storage tank 2, the water levels of all the storage tanks 2 are ultimately set to a position higher than the horizontal pipe section 4 b of the siphon pipe 4. Can be.

In the above-mentioned state, since air remains in the siphon pipe 4, the air bleeding valve 6 is opened and the air in the siphon pipe 4 is evacuated. If the air in the siphon pipe 4 is evacuated and the inside of the siphon pipe 4 is filled with water, then even if the water level in the storage tank 2 becomes lower than the highest point of the siphon pipe 4, one of the storage tanks 2 will pass through the siphon pipe 4. The water can move from the storage tank 2 to the other storage tank 2. Therefore, the water level of each storage tank 2 communicated with the siphon pipe 4 rises and falls substantially constantly as water is supplied or water is pumped from the storage tank 2. The airtightness inside the siphon pipe 4 is maintained, and the siphon pipe effect is maintained unless the water level drops below the lower end of the siphon pipe 4 during pumping (when using water).

FIG. 3 illustrates two means for pumping the water stored from the liquid storage tank 1. (A) shows a state in which the water absorption pipe 9 is installed in the storage tank 2 and the water absorption side of the commercially available engine pump P1 is connected to the water absorption pipe 9 to pump water during use. (B) shows the hand pump P2 installed in the storage tank 2. The lower end of the water absorption pipe 9 must be located above the open lower end of the siphon pipe 4.

Although three storage tanks 2 are shown in FIG. 1, the number and arrangement of the storage tanks 2 and the manner of connection by the siphon pipes 4 may be arbitrarily determined according to the purpose of installation, the place of installation, and the like. . For example, various modes as shown in FIG. 4 can be considered.

The second embodiment of the present invention will be described with reference to FIGS.
This will be described with reference to FIG. The liquid storage tank 11 of the present example is a water collecting basin 1
A plurality of storage tanks 13 are buried in 2. As the storage tank, a concrete pipe as described above may be used, or a steel pipe or a vinyl chloride pipe having a certain degree of flexibility may be used. However, it is preferable that the storage tank has such a strength that it is not easily broken even when subjected to an external pressure. The liquid storage tank 11 of this example is
This is a relatively large-scale liquid storage tank that is installed in factories, parking lots, grounds, sidewalks, road median strips, etc., and collects and stores surface water such as rainwater drainage.

As shown in FIGS. 5 to 6, a water collecting basin 12 having a rectangular shape in plan view is formed on the ground surface. The catch basin 12
It has a box shape partitioned by an outer frame concrete 12a on the inner side surface and a leveling concrete 12b on the bottom surface, and a lid 14 is attached to an opening on the ground surface. The lid 14 may be water-permeable, or a gap may be provided between the lid 14 and the opening to allow surface water to flow. Further, water from another drainage ditch or catchment basin (not shown) may flow in. The water collecting basin 12 and the lid 14 have a structure that does not hinder the passage of a person or a car thereover.

Leveling concrete 12b of the water collecting basin 12
, A plurality of (three in this example) cylindrical storage tanks 13 are arranged and fixed at predetermined intervals. The lower end in the ground of each storage tank 13 is closed. The open upper end of each storage tank 13 penetrates the layer of the leveling concrete 12 b and projects upward, and is located in the water collecting basin 12. Therefore, sand and gravel in the water collecting basin 12 are unlikely to enter the storage tank 13. In addition, if a mesh lid is provided at the upper end of the opened storage tank 13, it is possible to prevent floating substances in the water collecting basin 12 from entering the storage tank.

The adjacent storage tanks 13, 13 are connected by a siphon pipe 4. The adjacent storage tanks 13 and 13 are connected by a communication pipe 7. The connecting pipe 7 is located in the water collecting basin 12 above the horizontal pipe section 4b of the siphon pipe 4.
The connecting pipe 7 is fixed to the leveling concrete 12b of the water collecting basin 12, and is held in a horizontal state. In this example, since each storage tank 13 is opened in the water collecting basin 12, each storage tank 13 is opened.
Is not always necessary. The water collecting basin 12 of the liquid storage tank 11 may be connected to another water collecting basin or a gutter of a road.

The process of constructing the liquid storage tank 11 of this example will be described with reference to FIGS. 7 and 8. As shown in FIG. 7A, a groove 15 serving as a catchment basin is dug in the installation location. The width of the groove 15 serving as a water collecting basin is appropriately determined in consideration of workability and the like when the cylindrical storage tank 13 is buried in the bottom of the groove 15 in a later step. As shown in FIG. 7B, the earth auger excavator 16
The underground is excavated vertically from the bottom of the groove 15 by using.
As shown in FIG. 7 (c), the storage tank 1 to be buried as viewed from the ground surface
Drill to a deep position where 3 can be buried. The inner diameter of the drill hole is larger than the outer diameter of the storage tank 13. If the ground is liable to collapse, fill the borehole with muddy water and add it at the same time as excavation. The excavation wall is held down by the muddy water pressure and hardly collapses.

As shown in FIG. 8A, after the excavation is completed, a cylindrical storage tank 13 is built in the excavation hole. The storage tank 13 is previously set to an appropriate length on the ground. When the completed height of the storage tank 13 is large, the storage tank of a predetermined unit length may be assembled while sequentially lowering the storage tank into the drilling hole. Storage tank 13
If the lower end is open, the lower end is closed in advance using a lid or the like. Alternatively, use the one whose bottom end is closed from the beginning. Alternatively, even when the lower end remains open, the bottom of the excavation hole may be artificially formed as an impermeable layer, and the lower end opened here may be fitted. Alternatively, after the storage tank having the lower end opened is buried in the excavation hole, concrete or the like may be poured into the bottom of the storage tank to close the opening.

As shown in FIG. 8B, a filling layer 17 of sand or the like is provided between the inner circumference of the excavation hole and the outer circumference of the storage tank 13 (excess excavation portion) to stabilize the underground storage tank 13. The siphon pipe 4 is installed inside the storage tank 13. By repeating the above steps, a predetermined number of storage tanks 13 are installed underground.

As shown in FIG. 8 (c), the outer frame concrete 12a is formed by a concrete block on the side surface of the groove 15 opened on the surface of the earth, and the bottom surface of the groove 15 is leveled with concrete 1
Place 2b. The siphon tube 4 and the connecting tube 7 are connected. The usage of this example is similar to that of the first example.

A third embodiment of the present invention will be described with reference to FIG. The liquid storage tank 21 of this embodiment has substantially the same configuration as that of the second embodiment, but the connecting pipe 22 and the horizontal pipe section 4c of the siphon pipe 4 are formed of a flexible flexible pipe that can be extended and contracted and bent. . Therefore, it is less likely to be damaged by an external force such as an earthquake. The storage tank 23 is a steel pipe having an open lower end, and is closed by a bottom lid 24.
Other parts having the same configuration as the second example are shown in FIG.
The same reference numerals are given and the description is omitted.

A fourth embodiment of the present invention will be described with reference to FIGS. In the liquid storage tank 31 of this example, a plurality of storage tanks 33 buried in a row under a pavement 32 such as a sidewalk communicate with a siphon pipe 4, and the storage tank 33 is connected to a side groove 34 installed at a corner of the pavement 32 and a water pipe. It is a liquid storage tank that stores rainwater by tying at 35.

As shown in FIGS. 10 to 12, in the liquid storage tank 31 of the present embodiment, the inside of the flexible connecting pipe 36 connecting the adjacent storage tanks 33, 33 is placed inside the horizontal pipe portion 4b of the siphon pipe 4.
Is inserted. The horizontal pipe part 4b is arranged at the bottom in the communication pipe 36, and the highest water level in the communication pipe 36 is higher than the horizontal pipe part 4b, which is the highest point of the siphon pipe 4.

The connecting pipe 36 has an operation hole 37 communicating with the surface of the earth.
The air vent valve 38 provided in the horizontal tube portion 4b of the siphon tube 4 can be opened and closed through the operation hole 37. The procedure for removing air from the siphon tube 4 is as described above.

As shown in FIG. 12, the air vent valve 38
Is movable by screwing into a tubular female stopper 38b airtightly attached to a through hole formed in the peripheral wall of the horizontal tube part 4b and a screw hole 38a formed in the inner surface of the female stopper 38b which opens up and down. And a stopper 38c. Female stopper 38b
An air vent hole 38f penetrates through the peripheral wall of the horizontal pipe portion 4b to communicate the inside and the outside of the horizontal pipe portion 4b. A stopper 38d is provided at the lower end of the male plug 38c. The stopper 38d prevents the stopper 38c in contact with the end of the female stopper 38b in the horizontal tube portion 4b from coming off the upper end of the female stopper 38b. Horizontal tube part 4
An engaging portion 38e is provided at the upper end of the male plug 38c outside the b. An operating tool for rotating the male plug 38c is engaged with the engaging portion 38e. If an operating tool is coupled to the engaging portion 38e, the male plug 38c can be rotated by an operation from the ground surface. When the male stopper 38c is screwed into the screw hole 38a and the air vent hole 38f is closed, the siphon tube 4 is closed from the outside air. Rotating male stopper 38c, stopper 38
When c is moved upward and the air vent hole 38f is opened, the siphon tube 4 is opened to the outside air.

As shown in FIGS. 10 and 11, the storage tank 33
The bottom cover 39 provided at the lower end of the bottom has a locking portion 39a that protrudes outward in a flange shape. When a considerable amount of water is stored in the storage tank 33, the specific gravity of the entire storage tank is larger than the surrounding earth and sand. However, storage tank 33
If the earthquake occurs in a state where the water inside is small and the specific gravity of the entire storage tank is small, and the ground liquefies due to strong vibration, the storage tank 33 having a low specific gravity may be lifted to the ground by receiving buoyancy. According to this example, the locking portion 3 is provided at the bottom of the storage tank 33.
Since the storage tank 9a is provided, even in such a case, there is little possibility that the storage tank 33 is locked on the ground and lifts up.

As means for fixing the storage tank 33, in addition to the locking portion 39a, in the step of constructing the liquid storage tank 31,
It may be a packed layer of mortar or the like provided between the storage tank 33 and the excavation hole. In addition, when excavating a hole for burying the storage tank 33, when injecting muddy water to prevent collapse of the ground, a self-hardening stabilizing liquid such as mortar is injected during the same process, and excavation is performed after the storage tank 33 is buried. The periphery of the storage tank 33 may be individualized together with the earth and sand to form a filling layer.

A fifth embodiment of the present invention will be described with reference to FIGS. The liquid storage tank 41 of the present embodiment is formed by burying a box-shaped hollow storage tank 42 that communicates with the siphon tube 4. The siphon pipe 4 is disposed in the communication pipe 36. The air release valve 38 of the siphon pipe 4 is operated from the ground surface through the operation hole 38 of the communication pipe 36. The type of water to be stored, its use, the place where it is installed, and the like may be arbitrarily set within the range described in each example described above. Also,
Components similar in function to each of the above-described examples are denoted by the same reference numerals as in the above-described example, and description thereof will be omitted.

[0042]

EFFECT OF THE INVENTION In a general large storage tank formed by assembling a formwork in a pit excavated in the ground and casting concrete or the like, it is necessary to excavate the ground in a wide area, and the excavation opening is required during the working period. Leaving it unacceptable is a safety measure.
Further, depending on the earth retaining method for excavation, the influence on neighboring structures is also a problem. However, as is clear from the embodiments described above, in the construction of the liquid storage tank of the present invention, the ground is excavated in a vertical direction with a relatively small diameter with respect to the length (depth), so that the ground is relatively collapsed. And the impact on the neighborhood is small.

Further, even if the installation area is small, if a number of long (deep) storage tanks are arranged in a row and communicated with each other by the siphon pipe 4, the total amount of stored water will be sufficiently large. For this reason, a liquid storage tank can be installed even on narrow and irregularly shaped land that has not been considered as a storage location for storage tanks, such as sidewalks, median strips of roads, parks, and the periphery of grounds and parking lots. Can be used effectively enough to do.
In addition, by installing many storage tanks along the street under the street for the purpose of disaster prevention, firefighting facilities can be enhanced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a first embodiment of the present invention.

FIG. 2 is a diagram showing a fixing structure of a siphon tube according to the first embodiment.

FIG. 3 is a diagram illustrating a water pumping method according to the first embodiment.

FIG. 4 is a diagram illustrating an arrangement of storage tanks and a mode of connection by a siphon tube according to the first embodiment.

FIG. 5 is a sectional view of a second embodiment of the present invention.

FIG. 6A is a cross-sectional view taken along line AA of FIG. FIG. 6B is a cross-sectional view taken along line BB of FIG. 5.

FIG. 7 is a process chart for constructing a liquid storage tank according to the second embodiment.

FIG. 8 is a process chart for constructing a liquid storage tank according to the second embodiment.

FIG. 9 is a sectional view of a third embodiment of the present invention.

FIG. 10 is a sectional view of a fourth embodiment of the present invention.

FIG. 11 is a perspective view of a fourth embodiment of the present invention.

FIG. 12 is a sectional view of an air vent valve according to a fourth embodiment of the present invention.

FIG. 13 is a sectional view of a fifth embodiment of the present invention.

FIG. 14 is a perspective view of a fifth embodiment of the present invention.

FIG. 15 is a perspective view of a fifth embodiment of the present invention.

[Explanation of reference signs] 1,11,21,31,41 Liquid storage tanks 2,13,23,33,42 Storage tanks 4 Siphon pipes 6,38 Air vent valves as air venting means 7,22,36 Communication pipes 8 Supply pipes 12 Water box 17 Filled layer as fixing means 37 Operation hole 39a Locking portion as fixing means

Claims (10)

[Claims] 1. A liquid storage tank in which a plurality of storage tanks buried in the ground are connected by a siphon pipe. 2. The liquid storage tank according to claim 1, further comprising air venting means for venting air inside the siphon tube. 3. A water collecting basin that is formed in the ground to collect surface water, and an upper end of the water collecting basin that is buried and opened in the ground from the bottom of the water collecting basin is lower than the highest water level of the water collecting basin. The liquid storage tank according to claim 2, further comprising a plurality of storage tanks, wherein the highest point of the siphon pipe is lower than the highest water level of the water collecting basin. 4. The liquid storage tank according to claim 3, wherein the storage tank and the storage tank are connected to each other by a connecting pipe inside the water collecting basin. 5. A communication pipe having a water level higher than the highest point of the siphon pipe and connecting the storage tanks to each other, and a supply pipe supplying a liquid to at least a part of the storage tank. The liquid storage tank according to 2. 6. An air vent valve as the air vent means is provided at the highest point of the siphon pipe, the siphon pipe is inserted into the inside of the connecting pipe, and an operating hole for operating the air vent valve is provided in the connecting pipe. The liquid storage tank according to claim 5. 7. A fixing means is provided for fixing each storage tank to the ground in order to prevent each storage tank from rising from the ground due to the buoyancy force received from the ground when the amount of liquid stored in each storage tank decreases. The liquid storage tank according to claim 1. 8. The liquid storage tank according to claim 7, wherein the fixing means is a locking portion projecting from the bottom of each storage tank. 9. The liquid storage tank according to claim 7, wherein the fixing means is a packed layer provided between each storage tank and the ground. 10. The liquid storage tank according to claim 1, wherein each of the storage tanks has a vertically long cylindrical shape having a height larger than a diameter.