GB2194986A - Facilitating access to a submerged pump - Google Patents

Abstract

In a built-up water storage tank 1 composed of a plurality of unit panels, a submerged casing 6 disposed within the tank has a pumping unit 8 located therein. The pump draws water from the tank via the casing and a suction pipe 12 attached to the casing and discharges the water through an outlet 5. A valve 14 which is capable of being opened and closed by operation from outside the tank is disposed in the suction pipe. Thus, inspection or replacement of the pump can be performed without the need to drain the water within the tank, by closing the valve 14 and removing the pump from the discharge end of the casing. <IMAGE>

Description

SPECIFICATION Pump device for built-up water storage tank BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a pump device for a built-up water storage tank, the pump device being of the type used in a water storage tank adapted to allow a pump to be received therein for the purpose of reducing the amount of space required for installation, and more particularly to a pump device for a water-receiving tank provided in a multi-storied building.

Description of the Related Art Recently, built-up water storage tanks in which unit panels are successively joined to constitute the walls of the tanks are often used as water-receiving tanks provided in multi-storied buildings. The water within such a water-receiving tank is drawn therefrom to a reservoir provided in a similar manner on, for instance, the roof of the building. For this purpose, a usual arrangement is one wherein a pump is disposed beside the water-receiving tank. With this arrangement, a discharge port is formed in the bottom wall of the waterreceiving tank or a portion of a side wall of the tank which is close to the bottom, and a pipe extending from the discharge port is connected to the pump so that water is pumped out by subjecting the water to high pressure.

However, in order to meet the increasing demand for ensuring effective use of space, various attempts have been made to allow the main pump body to be accommodated within the water storage tank. For instance, Japanese Utility Model Laid-Open No.

123309/1977 proposes an arrangement in which a so-called deep well submersible pump is disposed on the bottom wall of the water storage tank. With this arrangement, water within the tank is led directly to the suction port of the submerged pump, while a short pipe extending from the pumping side passes through a side wall of the tank to serve as a discharge port for the water.

In addition, Japanese Utility Model Laid Open No. 21097/1984 proposes an improvement of the structure of Japanese Utility Model Laid-Open No, 123309/1977. The improvement comprises making it possible for the submerged pump to be taken out through the side wall in which the water discharge port is provided.

It is a matter of course that it will be necessary for these submerged pumps to be inspected and provided with maintenance after a certain period of use. With the arrangement of the proposals mentioned above, when the submerged pump is to be inspected or subjected to similar works, all the water within the water storage tank is first drained away, and this is followed by either the operator getting into the water storage tank through a manhole, as is the case with the first-mentioned arrangement, or the submerged pump being taken out of the tank through the side wall, as with the second mentioned arrangement.

However, in view of the primary purpose of storage which a tank is required to fulfill, it is impractical to drain all the water within the water storage tank whenever the submerged pump has to be inspected or subjected to maintenance works. To date, therefore, the above-described proposals have not been extensively used.

The defect of those roposals is consdem to be ascribable to the adoption of a design in which the submerged pump is disposed at the discharge port through which the water within the water storage tank is discharged therefrom. That is, with the structures of the proposals, it is completely impossible to provide any device capable of stopping the discharge of water from the water storage tank at the discharge port. Thus, although the proposals may seem to provide effective arrangement, in fact, a fundamental problem has to be solved before these proposals can be put into practical use.

SUMMARY OF THE INVENTION The present invention has been accomplished to minimise the defects of the prior art, and provides a pump device which facilitates the inspection and maintenance of the pump.

According to the present invention, a pump device for a built-up water storage tank composed of a plurality of unit panels joined to each other, is characterised by comprising: a side wall of the water storage tank having an opening formed therethrough; a submerged pump-receivable casing disposed within the water storage tank, the casing being fixed in such a position that it communicates with the opening; a water suction pipe connected to an intake opening of the casing; a valve disposed in the water suction pipe and capable of being opened and closed from outside the tank; a submerged pump inserted into the casing; and a coloumn pipe fixed to the opening from outside the tank.

In brief, the pump device for a built-up water storage tank in accordance with the present invention has the submerged pump provided at the discharge port through which the water within the water storage tank is discharged in such a manner that it can be taken out of the water storage tank, as well as a valve provided in a water suction pipe disposed inside the water storage tank in such a manner that it can be opened and closed from outside the tank. When the submerged pump is to be inspected or worked on for maintenance purposes, the valve is closed, stopping the flow of water from inside the water storage tank to downstream of the valve, and thereafter a flange provided on the outer side of the water storage tank is removed, thereby allowing the submerged pump which is received in the casing to be taken out therefrom.

With this arrangement, the submerged pump can be inspected while completely eliminating the need to drain the water within the water storage tank.

In other words, the present invention provides a pump device which allows the submerged pump to be taken out of the casing and inspected, when this is necessary, only after the valve provided in the water suction pipe disposed in the water storage tank is closed. The pump device is thus very simple, yet it is very effective, achieving an increase in operational efficiency, enabling the water within the water storage tank to be kept in storage at the time of inspection, and providing effective use of space.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a longitudinal sectional view through a pump device for a built-up water storage tank in accordance with the present invention; Figure 2 is a perspective view of an example of a valve used in the pump device in accordance with the present invention; and Figure 3 is a longitudinal sectional view through the valve shown in Fig. 2.

DESCRIPTION OF THE PREFERRED EMBODI MENT Fig. 1 shows a pump device for a water storage tank in accordance with an embodiment of the present invention. As shown in this figure, the water storage tank 1 has walls W1 and W2 which are formed by joining respective unit panels.

In this joining operation, a flange provided around the edge of a unit panel is secured to a flange of another unit panel by means of bolts and nuts (not shown). Side walls W1 and a bottom wall W2 are joined by securing the pressure-receivirig surfaces 2 of unit panels forming the side walls W1 to flanges 3 of unit panels forming the bottom wall W2.

An opening 4 is formed through the pressure-receiving surface 2 of a unit panel forming one of the side walls W1 of the water storage tank 1 so as to serve as a discharge port for the water within the water storage tank 1. Water flows out of the water storage tank from this discharge port through a column pipe 5. A pump casing 6 is connected to the opening 4 and is fixed to the side wall by a flange 7. The pump casing 6 is adapted to receive a submerged pump 8. The arrangement of the pump device is such that this submerged pump 8 can be taken out of the casing 6 by removing the column pipe 5 from the side wall W 1. The submerged pump 8 has an elongated shape consisting of a rear end portion forming a motor section 9, a front end portion forming a vane section 10, and a suction port 11 formed in the middle.Water led into the submerged pump 8 first flows around the motor section 9, enters the vane section 10 from the suction port 11, and is pressurized by the vane section 10 to be sent to the column pipe 5.

A suction pipe 12 is connected to an intake opening formed at the tip of the pump casing 6. A valve 14 is provided in this suction pipe 12. The valve 14 has a wheel 13 which is the only portion of the valve 14 that projects outside the water storage tank, and the wheel 13 normally projects from the bottom wall W2.

In Fig. 1, reference number 15 denotes a support for the pump casing 6, reference number 16 denotes a control panel, and reference number 17 denotes a line to the pump 8.

Fig. 2 is a perspective view of the valve 14 employed in the pump device of the present invention, showing an example of its structure.

Fig. 3 shows a longitudinal section through the valve 14 along its central axis.

In these drawings, the valve 14 (V) has a stem G having at one end the rotary wheel C (13) which constitutes the operation handle, and at the other end a disc H which acts as a valve opening-closing mechanism. A portion of the stem G which is closer to the wheel C is covered by a bonnet A which is threaded into a packing nut D through members including packing E such as to ensure water sealing.

The other side of the bonnet A has an external thread on which an internal thread of a body B is threaded.

The body B covers the disk H of the stem G and has a pipe-communication port I formed therein. This body B is threaded onto the bonnet A in such a manner that the body B and the bonnet A are threaded together in a hole formed in a flange F. For this purpose, the flange F projects radially outward from the gap between the body B and the bonnet A. In this way, the valve V is provided on its outer periphery with the flange F secured thereto for the purpose of fixing in place and supporting the valve V. The valve V is thus mounted on the unit panel 2 through the flange F by means of bolts and nuts (not shown). For this purpose, the flange should preferably have a plurality of round holes 20 formed therein.

The valve 14 having the structure described above is incorporated in such a manner that the wheel 13 (C) alone projects outside the water storage tank and the suction pipe 12 is connected to the body B. Therefore, the valve can be used when taking the submerged pump 8 out of the water storage tank by causing the disk H to block the flow of water.

As described above, by virtue of the pro vision of the valve on the suction side of the submerged pump in the water storage tank, when inspection or maintenance of the submerged pump is necessary, the flow of water can be stopped by the valve on that side and the submerged pump received in the casing can be taken out with ease through the conduit. The pump device of the present invention allows inspection or maintenance of the pump to be performed very easily while completely eliminating the need to drain the water stored within the water storage tank. Thus, the pump device of the present invention possesses high practical value.

Claims (6)

1. A pump device for a built-up water storage tank composed of a plurality of unit panels joined to each other, characterised by comprising: a side wall of said water storage tank having an opening formed therethrough; a submerged pump-receivable casing disposed within said water storage tank, said casing being fixed in such a position that it communicates with said opening; a water suction pipe connected to an intake opening of said casing; a valve disposed in said water suction pipe and capable of being opened and closed from outside said tank; a submerged pump inserted into said casing and a column pipe fixed to said opening from outside said tank.

2. A pump device for a built-up water storage tank according to claim 1, wherein said valve has a flange at which said valve is mounted on a wall of said water storage tank.

3. A pump device for a built-up water storage tank according to claim 1 or 2, wherein said valve includes a handle disposed outside said water storage tank for causing said valve to be opened and closed.

4. A pump device for a built-up water storage tank according to any preceding claim, wherein said casing has a flange at which said casing is fixed to said side wall in a water sealed manner.

5. A pump device for a built-up water storage tank according to any preceding claim, wherein said casing is a cylindrical member.

6. A pump device for a built-up water storage tank substantially as hereinbefore described with reference to the accompanying drawings.