JPH0515597Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a motor pump for draining residual water at a low water level, and in particular, the motor pump body is surrounded by a pump outer body, and the pump discharge water is transferred to the motor pump. This invention relates to an internal motor pump in which a motor is cooled by discharging air to the outside through a space between a main body and a pump outer shell.

[Conventional technology]

Conventionally, a submersible motor pump is installed immersed in a liquid tank, the discharge port of the submersible motor pump is opened to the liquid tank, and the pumped liquid is guided from the outside of the liquid tank to the pump suction port through a suction conduit. A so-called external motor pump, which discharges pump discharge water to the outside from a discharge port provided at the top of the liquid tank, is conventionally known. In addition, the suction conduit is made flexible so that its open end can be inserted into any liquid supply source as a liquid suction port, and when the liquid supply source has a shallow liquid depth, the liquid Conventionally, the pump was equipped with a self-priming function in order to prevent water from being sucked up and becoming unable to pump water due to air being sucked in through the suction opening end and causing aerodynamics in the pump chamber. Belongs to the public knowledge.

The above-mentioned external motor pump is mobile and has a self-priming function, so if a puddle in a civil engineering work site is selected as the liquid source, most of the remaining water will be removed from the liquid suction opening end. It is possible to inhale and drain water without any problem.

[Problem that the invention attempts to solve]

The conventionally known motor pump described above forms an external motor pump in which the submersible motor pump is installed in a liquid tank, and as can be seen from the fact that wheels are attached to the bottom of the liquid tank. However, since the entire device is large and heavy, and the liquid tank is also large, there was a problem in that a large amount of self-priming water was required when starting the pump.

On the other hand, there is an internal type in which the motor pump body is surrounded by a pump outer body, and the water discharged from the pump is discharged to the outside through a space formed between the motor pump body and the pump outer body, and the motor is cooled. Motor pumps have also been used for a long time, but
In this case, the space between the pump outer shell and the motor pump body is merely used as a pump discharge passage that also serves as a motor cooling water passage.

The technical object of the present invention is to provide a portable motor pump that is small, lightweight, and easy to carry, and is capable of draining residual water even at a low water level.

[Means for solving problems]

In order to solve the problems and technical problems of the conventionally known external motor pumps mentioned above, the present invention has the following features:
A pump unit driven by a motor is installed inside the liquid chamber,
In the motor pump, the pump part discharge port is opened into the liquid chamber, the pumped liquid is guided from the outside of the liquid chamber to the pump part suction port, and the pump discharge water is discharged from the liquid chamber to the outside. consists of a pump outer body, the upper opening of the pump outer body is covered by a head cover of the motor, and the head cover has a suction port that communicates with the pump suction port and discharges pump discharge water to the outside. A circulating water suction port for self-priming is opened in the empty space surrounded by the pump outer shell and the motor pump body, and the motor pump main body is disposed inside the pump outer shell. It is characterized in that the self-priming circulating water suction port and the suction port and discharge port on the head cover are arranged in a wide space created by the eccentricity.

[Effect]

Since the present invention is constructed as described above, when the pump is started, when the required amount of self-priming water is supplied into the pump outer body, the priming water is surrounded by the motor pump body and the pump outer body. stored in vacant rooms. Next, when the pump is started, the breathing water is sucked into the pump section, that is, into the pump chamber, from the self-priming circulating water suction port opened in the empty chamber, and this suction process is repeated on the suction side sucked into the pump suction port. It is pressurized together with air by an impeller, and is discharged into the pump outer body from the discharge port of the pump chamber as a mixture of air and water. This discharged air-water mixture is separated inside the pump outer body, the air is exhausted to the outside from the discharge port provided in the motor head cover, and only the liquid is pumped again from the self-priming circulating water suction port. The circulating flow that is sucked into the chamber and thus created produces a self-priming or vacuum suction effect.

Due to the above self-priming action, negative pressure is generated at the suction port of the motor head cover connected to the pump suction, and air is drawn out from the suction conduit connected to the suction port. As the air on the suction side is removed in this way, liquid is sucked in from the suction port at the tip of the suction conduit, and this sucked liquid joins the above-mentioned circulating water flow in the pump chamber and is pressurized by the impeller. , is discharged into the pump outer shell. The discharged liquid is drained from the discharge port of the motor head cover portion to a predetermined position while filling the inside of the pump outer body with water, and the self-priming action is completed.

As described above, after the self-priming action has ended and the pump has been switched to normal operation, it functions as a normal motor pump, and the pumped liquid sucked in from the suction port of the motor head cover is pressurized and discharged from the discharge port to a specified location. Also, during operation, when the suction side water level drops and air begins to be sucked in from the suction port, the self-priming action described above is performed appropriately, so the pump action continues without being interrupted by the aerodynamics, and almost all of the liquid can be sucked in without leaving any residual water.

In addition, since the motor pump body is eccentrically installed inside the pump outer body, the fluid discharged from the pump chamber discharge port flows through the eccentric annular cavity and reaches the discharge port, and a portion of the fluid flows through the circulating water. Because the process leading to the suction port becomes uneven and turbulent, less sediment settles to the bottom.

In addition, the pump outer shell is a small-volume one that is located below the motor head cover and is in charge of the pump outer shell in conventional internal pumps. Both self-priming action and motor cooling action are effectively performed internally.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a vertical sectional view taken along the line of FIG. 2 of a motor pump showing an embodiment of the present invention;
The figure is a plan view.

In the figure, a motor pump main body 2 is installed eccentrically inside a cylindrical pump outer shell 1 as shown in FIG. Motor head cover 3 with expanded
and the bottom is closed by a bottom plate 4, into which the motor pump body 2 is inserted and tightened with through bolts 5. As a result, the eccentric annular cavity 6 surrounded by the pump outer shell 1 and the motor pump main body 2 is kept in a sealed state.

The wide part of the peripheral part 3a of the motor head cover 3, that is, the part where the motor pump main body 2 is farthest from the pump outer body 1 (the left part in FIG. 2) has a suction port 7 and a discharge port 8. are provided close to each other, and the suction port 7 has a suction check valve 7.
A is built-in. When in use, a flexible suction conduit and a discharge pipe (not shown) are connected to the suction port 7 and the discharge port 8, respectively.

On the other hand, the pump section disposed at the lower end of the motor pump main body 2 has an impeller 22 retracted into the pump casing 21 close to the rear wall (upper cover in the figure) 21a of the casing, and has a wide front surface of the impeller 22. A so-called vortex pump is formed in which a gap (side clearance) _D4 is formed and foreign matter such as sand is carried out along with the vortex generated in the gap during pump operation, thereby reducing wear on the impeller. An airlock prevention nut 23 is attached to the inlet boss portion of the impeller 22.

The pump casing 21 has a pump chamber suction port 2.
4 is formed with an annular gap (minimum dimension) D ₃ maintained, and the pump chamber suction port 24 is connected to the suction passage 24.
a, it is connected to a pump casing suction port 25 corresponding to the pump section suction port. The pump casing suction port 25 is connected to the suction port 7 via a flexible hose 26 and a connecting pipe 26a.

Near the pump casing suction port 25,
A circulating water suction pipe 9 having an outlet nozzle 9a with a diameter D ₂ opened toward the suction passage 24a projects upward, and has a circulating water suction port 9b with a diameter D ₁ formed at the upper end. ing. The nozzle diameter D2 is smaller than the diameter _D1 of the circulating water suction port _9b , and the minimum diameter _D3 of the pump chamber suction port 24 is smaller than _D2 ,
Further, the side clearance D ₄ of the impeller 22 is larger than D ₃ and smaller than the nozzle diameter D ₂ .
These series of dimensions are designed to prevent foreign matter from clogging the nozzle or the like by repelling it at the pump chamber suction port when foreign matter enters the pump chamber.

On the other hand, the pump chamber discharge port 27 corresponding to the pump part discharge port opens into the eccentric annular inner cavity 6, that is, the pump outer body inner discharge chamber. In addition, in the figure, 31 is an elastic leg part, and 32 is a cable extraction part.

Next, the effect will be explained. When starting the pump,
When the required self-priming priming water is supplied into the pump outer body 1, the priming water is distributed between the motor pump body 2 and the pump outer body 1.
It is stored in an empty chamber (discharge chamber) 6 surrounded by. Next, when the pump is started, breathing water is sucked into the pump casing 21 from the self-priming circulating water suction port 9b opened in the empty chamber 6. In this process, the liquid sucked from the self-priming circulating water suction port 9b is ejected from the outlet nozzle 9a toward the suction passage 24a, causing a negative pressure in the outlet nozzle 9a section. Due to the generation of negative pressure, air flows through the suction port 7 of the motor head cover peripheral part 3a.
Air in a suction pipe (not shown) connected to the suction port 7 is sucked.

The air on the suction side sucked in as described above,
The liquid sucked from the self-priming circulating water suction port 9b,
The air-water mixture is pressurized in the pump chamber by the impeller 22 and is discharged from the pump chamber discharge port 27 into the empty chamber (discharge chamber) 6. This discharged air-water mixture is separated in the cavity 6, the air is expelled to the outside from the discharge port 8, and only the liquid is sucked in again from the self-priming circulating water suction port 9b. A circulating flow is formed and self-priming occurs.

Due to the above-mentioned self-priming action, as the air on the suction side is gradually removed, the liquid is sucked in from the suction port at the tip of the suction conduit (not shown) via the suction port 7 of the head cover section, and merges with the above-mentioned circulation flow in the pump chamber.
It is pressurized by the impeller 22 and discharged into the empty chamber 6.
With the discharged liquid filling the empty chamber 6 with water, the self-priming action is completed as the liquid is discharged from the discharge port 8 of the motor head cover.

After the self-priming action is completed in this way and normal pump operation begins, the pump functions as a normal motor pump, and the liquid sucked in from the suction port 7 of the motor head cover is pressurized by the impeller 22. The liquid is then discharged from the discharge port 8 to a predetermined location. During this normal operation period, even if sand or the like is sucked in from the suction port at the tip of the suction conduit (not shown), the pump part is formed as a vortex pump, so it will ride on the vortex generated in the space in front of the impeller 22. Since the water is discharged from the pump chamber discharge port 27, wear on the impeller 22 can be reduced.

Furthermore, even if the sand discharged from the pump chamber discharge port 27 is deposited in the cavity 6 in the pump outer body, pressurized water is discharged from the pump chamber discharge port 27.
The discharge port 27 is not filled with sand, and since the circulating water suction port 9b opens at a higher position than the main plate of the impeller 22, no sand is sucked in from the circulating water suction port 9b.

In addition, since the motor pump main body 2 is installed eccentrically within the pump outer shell 1, the pump chamber discharge port 2
As the fluid discharged from 7 flows through the eccentric annular cavity 6 and reaches the discharge port 8 and a part of it reaches the circulating water suction port 9b, it becomes uneven and turbulent. There is less sedimentation.

Also, if foreign matter gets mixed in during operation, the nozzle may be clogged with foreign matter because the diameter D ₁ of the circulating water suction port 9b and the diameter D ₂ of the nozzle 9a are larger than the minimum dimension D ₃ of the pump chamber suction port 24. Hateful. Further, during operation, when the water level on the suction side decreases and air is sucked from the suction port, the self-priming action described above is performed again, and the pumping action is continued without being interrupted by the air pump. Therefore, almost all of the remaining water is also sucked up. During this time, the liquid stored in the cavity 6 in the pump outer body not only prims for self-priming, but also performs a motor cooling action.

According to this embodiment, the following effects are achieved.

(i) The peripheral wall of the liquid tank of a conventional motor pump of this kind is constructed with the pump outer body 1 of an internal type motor pump, making the entire motor pump an internal type, and the pump outer body 1 is combined with the motor head cover 3 and the bottom plate. 4 and tightened with the bolt 5, it is small and lightweight, easy to carry, disassemble and inspect, and requires less priming water for self-priming.
Further, since the motor head cover 3 is open to the atmosphere, there is no need to make the motor cable outlet watertight as in the case of an external type, and the carrying handle can be attached directly to the motor head cover.

(ii) By eccentrically installing the motor pump main body 2 inside the pump outer shell 1, the pump chamber discharge port 27
Furthermore, the flow inside the pump outer body from the discharge port 8 of the head cover part to the circulating water suction port 9b becomes non-uniform and turbulent, which reduces the accumulation of dirt at the bottom.

In addition, the small pump outer body 1 is effectively utilized spatially to provide internal self-priming circulating water suction port 9b,
Suction port 7 and discharge port 8 on motor head cover
can be reasonably arranged.

(iii) Diameter D ₁ of circulating water suction port 9b, diameter of nozzle 9a
D ₂ , the minimum dimension D ₃ of the pump chamber suction port 24 and the clearance D ₄ in front of the impeller 22, D ₁ >D ₂ >
By setting D ₄ > D ₃ , if foreign matter gets mixed in, it will be blown away at the pump suction port,
Foreign matter is less likely to clog the nozzle, etc.

FIG. 3 is an explanatory sectional view showing another embodiment of the present invention, in which the same reference numerals as those shown in FIG. 1 indicate the same or similar parts.

In this embodiment, a nozzle 19 is provided at the pump suction port 25, and the axis 19a of the nozzle 19 is set to be parallel to the axis 2a of the motor pump body 2. The inlet portion and the suction port 7 of the motor head cover peripheral portion 3a are connected by a conduit 16. The conduit 16 is substantially parallel to the axis 2a of the motor pump body. In addition, the outer periphery of the tip 16a of the conduit 16 and the nozzle 19
An annular gap 19b with the inner surface serves as a circulating water suction port.

According to this embodiment, during self-priming, the circulating water is
Pass through the annular gap 19b as shown by arrow a,
It is sucked into the suction port passage 24a through the nozzle 19. This suction flow generates negative pressure in the vicinity of the conduit tip 16a due to the ejector action, and this negative pressure causes the air on the suction side to be sucked in from the suction port 7, which is different from the first embodiment (Fig. 1). However, in this embodiment, unlike the first embodiment, there is no need to separately provide a circulating water suction pipe, so the installation space for the nozzle is reduced, and the apparatus can be made compact. Note that if the conduit 16 is made flexible, there is no problem even if the positions of the nozzle 19 and the suction port 7 are slightly shifted.

FIG. 4 is a sectional view of a main part showing still another embodiment of the present invention, in which the same reference numerals as in FIG. 1 indicate the same or similar parts.

In this embodiment, a ball-shaped check valve 30 is provided at the upper end of the circulating water suction pipe 29 on the suction port 29b side. In the figure, 29a is a nozzle that is attached separately.

The check valve 30 is made of a material that floats due to buoyancy, and when the amount of circulating water is low, such as during self-priming, it does not come into contact with the bottom valve seat yet and floats to allow the circulating flow to pass (the figure shows (shows the state at this time), but after the self-priming action ends and normal operation begins, the pressure difference between the suction side and the discharge side of the pump chamber becomes large.
As the amount of circulating water increases, the check valve 30 is pressed downward and pressed against the bottom valve seat.

As mentioned above, during normal operation, circulating flow is blocked, which improves pump performance.
In addition, sand inside the pump outer shell 1 may be removed from the circulating water suction port 29b.
Since the sand does not enter the pump chamber, wear caused by sand in the pump chamber during normal operation is prevented.

In the above-described embodiments, a structure in which the pump part is a vortex pump has been explained, but the structure is not limited to this, and it is of course possible to use a vortex pump equipped with wear-resistant means. Although a structure has been described in which the bottom portion is constructed of a bottom plate and is fastened with a through bolt, it is also possible to form the pump outer body and the bottom plate integrally.

[Effect of idea]

As explained above, according to the present invention, the liquid chamber in which the motor-driven pump section is installed is constituted by the pump outer body of an internal motor pump, and the pump outer body is covered with the motor head cover section. The head cover section is provided with a suction port that communicates with the pump section suction port and a discharge port that discharges the pump discharge water to the outside, and a self-contained pump is provided in the empty space surrounded by the pump outer body and the motor pump body. By opening the suction circulating water suction port, water can be stored up to the upper part of the pump's outer body, and the overhang to the outside diameter side can be reduced, making the entire motor pump compact. It can be made lightweight. Therefore, it is easy to carry, and the interior can be easily inspected by removing the motor head cover.

Due to the eccentric installation of the motor pump body inside the pump outer shell, the flow inside the pump outer shell from the pump chamber outlet to the head cover outlet and part of it to the circulating water suction port becomes uneven. As turbulence occurs, there is less accumulation of dirt at the bottom, and the small outer body of the pump can be used space-wise to effectively connect the internal self-priming circulating water suction port and the suction port on the motor head cover. And the discharge ports can be arranged rationally.

In addition, since the liquid storage part is smaller than that of conventional external pumps, less priming water is required for self-priming, and even a small amount of residual water can be easily drained with this small amount of priming water.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view taken along line Fig. 2 of a motor pump showing one embodiment of the present invention, Fig. 2 is a plan view thereof, and Fig. 3 is an explanatory sectional view showing another embodiment of the present invention. , FIG. 4 is a sectional view of a main part showing still another embodiment of the present invention. 1...Pump outer body, 2...Motor pump body,
3...Motor head cover, 4...Bottom plate, 5...
Through bolt, 6... Empty chamber (discharge chamber), 7... Suction port, 8... Discharge port, 9a, 19, 29a... Nozzle, 9b, 19b, 29b... Circulating water suction port, 2
1... Pump casing, 22... Impeller, 24
... Pump chamber suction port, 25 ... Pump part (casing) suction port, 27 ... Pump chamber discharge port, 30 ...
...Ball type check valve.

Claims (1)

[Claims for Utility Model Registration] 1. A pump section driven by a motor is installed in a liquid chamber, a discharge port of the pump section is opened into the liquid chamber, and the pumped liquid is introduced from the outside of the liquid chamber to the suction port of the pump section. In the motor pump, the liquid chamber is configured by a pump outer body, and the upper opening of the pump outer body is covered by a head cover portion of the motor, The head cover section is provided with a suction port communicating with the pump section suction port and a discharge port for discharging pump discharge water to the outside, and in a vacant space surrounded by the pump outer body and the motor pump body, At the same time as opening the self-priming circulating water suction port,
The motor pump main body is eccentrically installed in the outer body of the pump, and the self-priming circulating water suction port and the suction port and discharge port on the head cover are arranged in the wide space created by the eccentricity. A portable motor pump characterized by: 2. The portable motor pump according to claim 1, wherein the self-priming circulating water suction port is provided at a higher position than the bottom surface of the impeller main plate of the pump section.