JPH06248690A - Rain water drainage pump device - Google Patents

Abstract

PURPOSE:To prevent the accumulation of earth to a pump absorption side at a rain water drainage pumping station wherein installation of a sufficient grit chamber in hard to the upper stream side, and to promote reliability of the device. CONSTITUTION:Rain water from an inflow main line 2 is decelerated by an uneven step 6, and earth falls down to the bottom directly before the uneven step 6 and is accumulated. The accumulated earth is eliminated by a sand pump 8, and slit deposition in a water tank 4 can be prevented. In order to prevent the outflow of the fallen earth, a ditch can be provided directly before the uneven step 6 or a down slope can be provided to the bottom of the water tank. The uneven step 6 is so curved that it is perpendicular in the direction of the current and can be provided. Rain water from the inflow main line 2 is greatly decelerated at the water tank 4, earth can be easily accumulated, so that the earth is accumulated at a specific place by the uneven step and is eliminated, and deposited silt in a water absorption tank on a pump absorption side can be prevented and also can be eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rainwater drainage pump device, and more particularly to a rainwater drainage pump device suitable for pump equipment in which it is difficult to provide a sufficient sand basin upstream of the drainage pump.

[0002]

2. Description of the Related Art In recent years, rainwater drainage pumps are becoming deeper, mainly in urban areas. Particularly, in the conventional pump equipment for deep underground use, as described in Japanese Utility Model Laid-Open No. Sho 63-60100, a bypass pipe is provided from the inlet of the pump impeller, and it is generated by the swirling flow generated when the pump is shut off. There is a method in which water is guided to the suction side through the bypass pipe by the pressure applied to float the earth and sand accumulated in the water absorption tank.
Sufficient agitation cannot be achieved only by the pressure when the pump is shut off, and therefore, the sand is not sufficiently floated.

[0003]

One of the problems of the above-mentioned deep underground pumping equipment is that if a sand basin of sufficient size is installed on the upstream side, a huge amount of excavation and civil engineering and construction costs associated therewith will occur. There are points that are necessary. In addition, if rainwater flows in as it is, sediment may accumulate on the side of the water absorption tank.If there is a large amount of sediment, the loss on the suction side will increase and the discharge amount of the pump will decrease. In some cases, the suction side of the pump may be blocked.

An object of the present invention is to avoid the above problems by discharging as much sediment as possible on the pump suction side in pump equipment in which it is difficult to provide a sand basin of sufficient size on the upstream side. Therefore, it is to provide a more reliable rainwater drainage pump device.

[0005]

In order to achieve the above object, the present invention provides a rainwater drainage pump device in which it is difficult to provide a sand basin of a sufficient size upstream of a drainage pump.
It is characterized in that a step is provided on the bottom surface of the landing well installed on the upstream side of the drainage pump. Further, a step is provided on the bottom surface of the landing well installed on the upstream side of the drainage pump, and a groove is provided immediately before the step. Further, a step is provided at the bottom of the landing well installed on the upstream side of the drainage pump so as to be perpendicular to the flow direction of rainwater flowing into the landing well from the inflow trunk line. Further, a step is provided on the bottom surface of the landing well installed on the upstream side of the drainage pump so as to be perpendicular to the flow direction of rainwater flowing into the landing well from the inflow trunk line, and a groove is provided immediately before the step. It is a thing. In addition, a step is provided on the bottom surface of the landing well installed upstream of the drainage pump just before the suction flow path of the drainage pump. In addition, the landing well installed upstream of the drainage pump is provided with a step on the bottom surface immediately before the suction flow path by the drainage pump, and a groove is provided immediately before the step. Further, a step is provided on the bottom surface of the inflow part from the inflow trunk line of the landing well installed on the upstream side of the drainage pump. Further, the landing well installed upstream of the drainage pump is provided with a step on the bottom surface of the inflow portion from the inflow trunk line, and a groove is provided immediately before the step. Further, the bottom surface of the landing well installed upstream of the drainage pump is provided with a downward slope with respect to the flow direction. Further, a step is provided on the bottom surface immediately before the inlet of the vertical shaft installed on the upstream side of the drainage pump.

[0006]

[Operation] It is difficult to provide a sufficient sand basin on the upstream side of the drainage pump, for example, in the case of a pumping station for deep underground use, sand will be deposited in the pump suction passage. According to the above configuration of the present invention, stagnation is generated by the step provided in the landing well, and the earth and sand flowing in together with the rainwater falls to the bottom surface portion.
The sediment thus accumulated can be discharged by a sand pump. In addition, by providing the groove immediately before the step, the earth and sand that have fallen can be accumulated in the groove and reliably discharged. Further, by providing the step or the groove perpendicular to the flow of water in the landing well, the sediment does not slide and the sand removal rate can be increased. Also,
By creating a step at the inflow part of the landing well, stagnation is generated, and sand is deposited and removed at that part,
It is possible to prevent the inflow of sediment into the landing well. In addition, due to the downward slope formed on the bottom surface of the landing well, a step is created between the pump suction flow path and the step causes stagnation.
The earth and sand fall. This sand is discharged by a sand pump. In addition, a stagnation occurs due to the step provided at the entrance of the shaft in the middle of the inflow trunk line, and in the same manner as above, by removing the accumulated sediment, it is possible to prevent the sediment from flowing into the shaft.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing a first embodiment of the present invention. When the rainwater flowing in from the inflow trunk line 2 enters the landing well 4, the flow velocity sharply decreases, so that sediment is likely to accumulate. Therefore, by providing the landing well 4 with a step 6 facing in the flow direction, the inflow trunk line 2
Rainwater flowing from the ground is decelerated by the step 6 and
Sediment is deposited on the bottom just before. By removing the accumulated sediment with the sand pump 8, sedimentation of the landing well 4 can be prevented. Although the step 6 is provided immediately before the suction flow path 10 in FIG. 1, the step 6 can be provided at an appropriate position on the bottom surface of the landing well 4.

2 and 3 show a second embodiment of the present invention. FIG. 2 is a sectional view and FIG. 3 is a plan view. When the rainwater flowing in from the inflow trunk line 2 enters the landing well 4, the flow velocity sharply decreases, so that sediment is likely to accumulate. Therefore, by providing the groove 12 immediately before the step 6 of the landing well 4, the rainwater flowing from the inflow trunk line 2 is prevented from having the step 6
Due to this, it is possible to deposit the fallen earth and sand in the groove 12. Furthermore, by removing the sediment deposited in the groove 12 by a sand pump, it is possible to prevent the sediment from flowing into the landing well 4.

FIG. 4 is a plan view showing a third embodiment of the present invention. In the embodiment shown in FIG. 3, the step 6 and the groove 1
2 is provided linearly with respect to the flow, but in the present embodiment, as shown in the figure, the step 6A and the groove 12A immediately before the step 6A are arranged so as to be perpendicular to the flow direction of the water in the landing well 4.
Is curved. According to this embodiment, since the step 6A and the groove 12A are provided perpendicularly to the water flow direction, the sand can be reliably dropped into the groove 12A without slipping of sand in the water flow direction. The sand removal rate can be made higher than in the above-mentioned embodiment.

FIG. 5 is a sectional view showing a fourth embodiment of the present invention. Sediment flowing in from the inflow trunk line 2 is stagnated by the step 6B provided at the front side inflow part of the landing well 4, and the groove 12B
Let it settle down. Further, the earth and sand accumulated in the groove 12B are collected by a sand pump. According to this embodiment, it is possible to prevent the inflow of earth and sand into the landing well 4 near the inlet.

FIG. 6 is a sectional view showing a fifth embodiment of the present invention. Sediment entering the landing well 4 from the inflow trunk line 2 is deposited on the deepest portion 16 along the inclined portion 14 formed on the bottom surface of the landing well 4. Further, the earth and sand floating in the water settles due to the stagnation generated by the step 6 between the deepest portion 16 and the suction flow passage 10. Further, the earth and sand deposited on the deepest part 16 are discharged by a sand pump. According to the present embodiment, it is possible to reliably collect and discharge both the earth and sand that have flowed by sweeping and the earth and sand that have flowed by floating.

FIG. 7 is a sectional view showing a sixth embodiment of the present invention. The earth and sand will also accumulate in the shaft 8 in the middle of the inflow trunk line 2. Therefore, by providing the step 6C and the groove 12C near the inlet of the vertical shaft 18 in the same manner as described above,
The rainwater flowing in the inflow trunk line 2 stagnates due to the step 6C, the flow velocity decreases, and the earth and sand fall and accumulate in the groove 12C. By discharging the sediment accumulated in the groove 12C with a sand pump, it is possible to prevent the accumulation of sediment in the vertical shaft. Further, it becomes possible to prevent the inflow of earth and sand into the pump suction side water tank.

Incidentally, rainwater drainage pump facilities in large cities tend to be deeper due to the widening of drainage target areas and the influence of existing underground structures. As a result, arranging a settling basin on the inflow side requires enormous excavation and civil engineering structures, resulting in an increase in construction costs. In addition, when drainage operation is performed with a rainwater drainage pump facility that does not have a sand basin on the upstream side, rainwater will be discharged to areas where the flow velocity suddenly slows (approximately 0.8 m / sec or less), such as landing wells, steps, and stagnation. If the amount of sediment that is mixed in with the sediment accumulates and the amount of sediment increases, the loss on the suction side of the pump will increase from the time of planning, so there is a risk that the drainage of the pump will decrease or the pump will become blocked. Therefore, as in these examples, by providing a groove in the stepped portion of the landing well, stagnation can be caused to occur, and earth and sand can be deposited in the groove and discharged by means of a sand pump or the like.

[0014]

According to the present invention, in a rainwater pumping station where it is difficult to provide a sufficient sand basin upstream of the pump,
It is possible to remove sediment on the suction side of the pump.

[Brief description of drawings]

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

FIG. 2 is a sectional view showing a second embodiment of the present invention.

FIG. 3 is a plan view showing a second embodiment of the present invention.

FIG. 4 is a plan view showing a third embodiment of the present invention.

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

FIG. 6 is a sectional view showing a fifth embodiment of the present invention.

FIG. 7 is a sectional view showing a sixth embodiment of the present invention.

[Explanation of symbols]

 2 Inflow trunk line 4 Landing well 6, 6A, 6B, 6C Step 8 Sand pump 10 Suction flow path 12, 12A, 12B, 12C Groove 14 Inclined part 16 Deepest part 18 Vertical shaft

Claims (10)

[Claims] 1. In a rainwater drainage pump device in which it is difficult to provide a sand basin of a sufficient size upstream of a drainage pump, a step is provided on the bottom surface of a landing well installed upstream of the drainage pump. A rainwater drainage pump device characterized in that 2. A rainwater drainage pump device in which it is difficult to provide a sand basin of sufficient size upstream of the drainage pump, and a step is provided on the bottom surface of the landing well installed upstream of the drainage pump. A rainwater drainage pump device characterized in that a groove is provided immediately before the step. 3. In a rainwater drainage pump device in which it is difficult to provide a sand basin of sufficient size upstream of the drainage pump, the bottom of the landing well installed upstream of the drainage pump is connected to the bottom of the inflow trunk line. A rainwater drainage pump device characterized in that a step is provided so as to be perpendicular to the flow direction of rainwater flowing into the landing well. 4. In a rainwater drainage pump device in which it is difficult to provide a sand basin of a sufficient size upstream of the drainage pump, the bottom of the landing well installed upstream of the drainage pump is connected to the bottom of the inflow trunk line. A rainwater drainage pump device characterized in that a step is provided so as to be perpendicular to the flow direction of rainwater flowing into the landing well, and a groove is provided immediately before the step. 5. In a rainwater drainage pump device in which it is difficult to provide a sand basin of sufficient size upstream of the drainage pump, a drainage pump suction passage of a landing well installed upstream of the drainage pump. A rainwater drainage pump device having a step on the bottom surface immediately before. 6. A rainwater drainage pump device in which it is difficult to provide a sand basin of sufficient size upstream of a drainage pump, and a suction flow path of the drainage pump of a landing well installed upstream of the drainage pump. A rainwater drainage pump device characterized in that a step is provided on the bottom surface immediately before and a groove is provided immediately before the step. 7. A rainwater drainage pump device in which it is difficult to provide a sand basin of a sufficient size upstream of the drainage pump, and an inflow part from an inflow trunk line of a landing well installed upstream of the drainage pump. A rainwater drainage pump device characterized in that a step is provided on the bottom surface of the. 8. A rainwater drainage pump device in which it is difficult to provide a sand basin of sufficient size upstream of the drainage pump, and an inflow part of an inflow well of an landing well installed upstream of the drainage pump. A rainwater drainage pump device, characterized in that a step is provided on the bottom surface of the, and a groove is provided immediately before the step. 9. In a rainwater drainage pump device in which it is difficult to provide a sand basin of a sufficient size upstream of the drainage pump, a rainwater drainage pump device is provided at the bottom of a landing well installed upstream of the drainage pump in a flow direction. On the other hand, a rainwater drainage pump device having a downward slope. 10. In a rainwater drainage pump device in which it is difficult to provide a sand basin of a sufficient size upstream of the drainage pump, a step is formed on the bottom surface immediately before the inlet of a vertical shaft installed upstream of the drainage pump. A rainwater drainage pump device characterized by being provided with.