JPH0549834B2 - - Google Patents

Description

[Detailed Description of the Invention] (1) Purpose The present invention relates to a residual water treatment device for a submersible pump.

In general, the lowest water level that can be drained from the installation floor of a submersible pump is limited by the height of the strainer stand, etc., and complete drainage is not possible at low water levels, resulting in several centimeters of residual water. This is the actual situation, and therefore, it is completely impossible to use the submersible pump to absorb accumulated water from the floor. As a measure to enable drainage at low water levels, there are pumps in which the opening position of the pump suction port is made as low as possible, but this has the disadvantage that water inside the pump casing and piping flows backwards when the pump is stopped. are doing.

The purpose of the present invention is to eliminate the above-mentioned conventional drawbacks, to completely drain water at a low water level without producing residual water, and to prevent backflow of water even when the pump is stopped. To construct a submersible pump which can also be used for sucking up water accumulated on a floor.

(2) Configuration In the residual water treatment device for a submersible pump according to the present invention,
A bottom plate is fixed at a predetermined distance from the suction cover constituting the lower bottom of the pump swirl chamber, and an annular mantle wall is provided between the opposing surfaces of the suction cover and the bottom plate, and a bowl-shaped mantle is provided within the mantle wall. A swing valve is installed that rotates up and down using the center of the elastic membrane as a fulcrum, a ring-shaped seat is provided around the lower surface of the bottom plate, and a number of narrow water holes are carved in the lower edge of the seat, and By opening a suction hole from the bottom of the bottom plate toward the recess on the lower surface of the swing valve, when the swing valve is turned upward, the lower edge around the bowl-shaped elastic membrane is separated from the top of the bottom plate, and the outer periphery of the lower edge of the annular seat is The water passage leading to the pump suction port is opened further, and when the swing valve is rotated downward, the peripheral lower edge of the bowl-shaped elastic membrane comes into close contact with the bottom plate to close the water passage.

To explain the drawings of the embodiment, 1 is a pump vortex chamber, 2 is a suction cover constituting the lower bottom of the pump vortex chamber 1, and a pump suction port 3 is bored in the center. 4 is a bottom plate fixed at a predetermined distance S from the suction cover 2; 5 is the suction cover 2;
It is also a mounting bolt for fixing the bottom plate 4. 6 is a stud bolt planted in the center of the upper surface of the bottom plate 4; 7 is a swing valve in which the center of a bowl-shaped elastic membrane is fixed to the stud bolt 6; Within the provided annular mantle wall 8, the bowl-shaped elastic membrane rotates up and down using the center as a fulcrum. 9...9 is a suction hole opened from below the bottom plate 4 toward the bottom recess 10 of the swing valve 6; 11 is an annular seat attached to the periphery of the bottom surface of the bottom plate 4; A large number of narrow water holes 12...12 are carved on the lower edge. During the downward movement of the swing valve 7, the peripheral lower edge 13 of the bowl-shaped elastic membrane comes into close contact with the top of the bottom plate 4. Peripheral subordinate 13
It is desirable to provide a resilient protrusion 14 on the surface, and it is best to form the protrusion 14 sharply so that the close contact portion is in line contact. Further, when the swing valve 7 is operated to rotate upward, a predetermined gap g must be maintained between the peripheral portion 15 of the bowl-shaped elastic membrane and the suction cover 2, and a stopper is provided to ensure that this gap g is maintained. 16...16 may be arranged at appropriate intervals in the circumferential direction along the upper edge 15 of the periphery of the bowl-shaped elastic membrane, or may be arranged on the lower surface of the suction cover 2 so as to face the upper edge 15. .

To apply the device of the present invention, it is sufficient to fix the bottom plate 4 with the swing valve 7 attached together with the annular jacket wall 8 in the place where the bottom plate of the strainer stand of an existing submersible pump has been removed.

When the submersible pump is stopped, the downward movement of the swing valve 7 causes the peripheral lower edge 13 of the bowl-shaped elastic membrane to close to the bottom plate 4.
Since they are in close contact with each other upward, the suction holes 9...9 of the bottom plate 4 and the pump suction port 3 are in a state where electrical conduction is interrupted. But if you start the submersible pump at water level l ₁ ,
Since negative pressure is generated at the bottom of the impeller, the swing valve 7 operates upward, and the peripheral lower edge 13 of the bowl-shaped elastic membrane is separated from the top of the bottom plate 4, and the suction holes 9...9 and the pump suction port 3 are separated from each other.
The water passage 17 from the outer circumference of the lower edge of the annular seat 11 to the pump suction port 3 is opened, and the narrow water passage 12 is in a conductive state.
... 12 is drained from the water passage 17 through the inside of the pump casing 1 and from the discharge port (not shown). When the submersible pump stops at the completed water level _l2 , the swing valve 7 is rotated downward due to the pressure of the return water in the pump casing 1 and the drainage piping, and the lower edge 13 around it is brought into close contact with the bottom plate 4. Therefore, the backflow prevention function is activated.

Note that if the elastic protrusion 14 is provided on the bottom plate 4 and the protrusion 14 is formed sharply, the swing valve 7
The lower edge 13 of the periphery is brought into close contact with the peripheral lower edge 13 to enhance the sealing effect, and at the same time, it is possible to prevent foreign matter such as sand grains from clogging the close contact area.

(3) Effects According to the present invention, the narrow gap-shaped water inlet 12 is opened at an extremely low position close to the installation floor of the submersible pump.
12 is connected to the inside of the pump casing 2 through a water passage 17 with a backflow prevention structure, so drainage is completely carried out at low water levels without residual water, and water does not flow back even when the pump is stopped. This has the advantage that it can also be used to absorb standing water from the floor. Moreover, in carrying out the present invention, it is sufficient to fix the bottom plate 4 with the swing valve 7 attached thereto together with the annular mantle wall 8 in the part from which the bottom plate of an existing submersible pump has been removed. is extremely high.

[Brief explanation of drawings]

The drawing is a vertical sectional side view of the main part of a submersible pump equipped with the device of the present invention, and Fig. 1 shows an example in which elastic convexes are provided on the bottom plate and stoppers are provided at the upper part of the periphery of the bowl-shaped elastic membrane. , Fig. 2 shows an example in which elastic convexes are provided on the lower edge of the periphery of the bowl-shaped elastic membrane, and a stopper is provided on the lower surface of the suction cover, and A in Figs. 1 and 2 shows the downward movement of the swing valve. B in FIGS. 1 and 2 shows the state when the swing valve is in upward rotation operation. DESCRIPTION OF SYMBOLS 1... Pump swirl chamber, 2... Suction cover, 3... Pump suction port, 4... Bottom plate, 7... Swing valve, 8... Annular mantle wall, 9... Suction hole, 10... Bottom recess, 11... Annular seat, DESCRIPTION OF SYMBOLS 12... Narrow gap-shaped water inlet, 13... Peripheral lower edge of bowl-shaped elastic membrane, 17... Water passage, S... Predetermined gap.

Claims (1)

[Claims] 1 Fixing the bottom plate 4 at a predetermined distance S from the suction cover 2 that constitutes the lower bottom of the pump swirl chamber 1,
An annular mantle wall 8 is provided between the opposing surfaces of the suction cover 2 and the bottom plate 4, and within the mantle wall 8,
A swing valve 7 is installed that rotates vertically using the center of the bowl-shaped elastic membrane as a fulcrum, and an annular seat 11 is provided around the lower surface of the bottom plate 4, and narrow water holes 12...12 are provided at the lower edge of the annular seat 11. By forming a large number of suction holes 9 toward the lower surface recess 10 of the swing valve 7 from the lower side of the bottom plate 4, when the swing valve 7 is operated upwardly, the peripheral lower edge 13 of the bowl-shaped elastic membrane is spaced apart from the top of the bottom plate 4 to open a water passage 17 extending from the lower edge outer periphery of the annular seat 11 to the pump suction port 3, and when the swing valve 7 is in downward rotation operation, the peripheral lower edge 13 of the bowl-shaped elastic membrane A residual water treatment device for a submersible pump, characterized in that it is configured so that the water passageway 17 is closed by coming into close contact with the bottom plate 4.