JPH0727087A - Pump device - Google Patents

Abstract

PURPOSE:To provide a pump device capable of preventing an excessive flow amount by the simple device having no movable part. CONSTITUTION:A device comprises a pump 1 for boosting a pressure of liquid to press feed it, fluid element 2 for suppressing a flow by giving it a rotating field and a negative pressure generator 8 set up in a delivery port of the pump 1 to generate a negative pressure at excessive flow time, to connect a suction port 1a of the pump 1 to a delivery port 5 of the fluid element 2, and the negative pressure generator 8 is connected to a rotating field generating nozzle 6 of the fluid element 2 by a bypass pipe 12, to also provide a check valve 13 in the bypass pipe 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pump device, and more particularly to a pump device suitable for preventing an excessive flow rate of a pump.

[0002]

2. Description of the Related Art Generally, the output of a centrifugal pump is over on the side of a large amount of water outside the specification range. In addition, due to circumstances on the piping side, problems often occur when an excessive flow rate flows. There are also cases where the head changes from moment to moment but the flow rate does not want to change.

[0003]

In order to deal with these problems, it has conventionally been necessary to separately prepare a flow rate control device having a movable structure and a complicated structure.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a pump device capable of preventing an excessive flow rate with a simple device having no movable portion.

[0005]

In order to achieve the above-mentioned object, a pump device of the present invention comprises a pump for pressurizing and pumping a liquid, and a fluid element for suppressing the flow by giving a rotating field to the flow. A negative pressure generating device installed at the discharge port of the pump to generate a negative pressure when the flow rate is excessive, the suction port of the pump and the discharge port of the fluid element are connected, and the negative pressure generating device and the fluid element are connected. The rotary field generating nozzle is connected by a bypass pipe, and a check valve is provided in the bypass pipe.

[0006]

In the present invention, a fluid element is connected to the suction side of the pump, and a nozzle for generating a rotating field is provided in the fluid element. This nozzle is connected to the ejector on the pump discharge side through a bypass pipe. Connected. A check valve is provided in this bypass pipe. As a result, the pressure in the ejector section is higher than the pressure in the fluid element during normal operation. Therefore, the handled liquid tries to flow into the fluid element from the ejector portion, but this flow does not occur because the check valve is provided. As a result, the fluid element does not restrict the flow on the suction side of the pump.

On the other hand, when the flow rate is excessive, the pressure in the ejector section becomes lower than the pressure in the fluid element (set to be lower). Therefore, a flow is generated from the fluid element side toward the ejector. This flow becomes faster as the flow rate of the pump becomes higher. On the other hand, since the fluid element is provided with the rotation field generating nozzle, the rotation field is generated by the above flow. As a result, since the flow on the suction side of the pump is suppressed, the flow rate of the pump is reduced. When the pump flow rate is reduced, the rotating field in the fluid element is weakened, so that the effect of suppressing the flow on the pump suction side is also weakened and the pump flow rate is increased.
In this way, the pump is stably operated at either flow rate.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the pump device according to the present invention will be described below with reference to FIGS. 1A and 1B are diagrams showing the overall configuration of a pump device. FIG. 1A is a partial cross-sectional front view, and FIG. 1B is a view taken along arrow I (b) of FIG. 1A.
In FIG. 1, reference numeral 1 is a pump, and a fluid element 2 is arranged on the suction side of the pump 1. An ejector 8 is installed on the discharge side of the pump 1. The fluid element 2 is
A cylindrical main body 3, a suction port 4, a discharge port 5, and a rotating field generating nozzle 6 are provided, and the discharge port 5 is connected to the suction port 1 a of the pump 1.

The ejector 8 has a main body 9, a diffuser 10 extending from the main body 9, and a nozzle 11 provided in the main body 9. The main body 9 has a bypass pipe 12.
Is connected to the rotating field generating nozzle 6 of the fluid element 2 by
The nozzle 11 is connected to the discharge port 1b of the pump 1.
A check valve 13 is provided in the bypass pipe 12.

Next, the operation of the pump device constructed as described above will be described. (1) During Normal Operation During normal operation, the pressure inside the ejector 8 is higher than the pressure inside the fluid element 2. Therefore, the handled liquid tries to flow from the ejector 8 into the fluid element 2, but this flow does not occur because the check valve 13 is provided. As a result, the fluid element 2 does not suppress the flow on the suction side of the pump 1 (FIG. 1).
(See (b)). (2) At an excessive flow rate At an excessive flow rate, the pressure inside the ejector 8 becomes lower (set lower) than the pressure inside the fluid element 2.
Therefore, as shown in FIG. 2A, a flow from the fluid element 2 to the ejector 8 through the bypass pipe 12 is generated. This flow becomes faster as the flow rate of the pump 1 becomes larger. On the other hand, since the fluid field 2 is provided with the rotation field generating nozzle 6, the rotation field is generated by the above flow (see FIG. 2B). As a result, since the flow on the suction side of the pump 1 is suppressed, the flow rate of the pump 1 is reduced. Then, when the pump flow rate is reduced, the rotating field in the fluid element 2 is weakened, so the effect of suppressing the flow on the suction side of the pump 1 is also weakened, and the pump flow rate is increased. In this way, the pump is stably operated at either flow rate.

FIG. 3 is a diagram showing a characteristic curve of the pump device according to the present invention, in which the horizontal axis shows the flow rate (Q), and the vertical axis shows the lift (H) and the pump shaft power (L). As is apparent from the figure, when the flow rate discharged from the pump 1 becomes excessive and the ejector 8 operates to form a rotating field in the fluid element 2, that is, when the operating point of the excessive flow prevention device is reached, The flow rate is constant.

[0012]

As described above, according to the present invention, the fluid element having no movable portion is provided on the suction side of the pump, and the ejector is provided on the discharge side of the pump. Can be prevented and the flow rate discharged from the pump can be prevented from becoming excessive.

[Brief description of drawings]

FIG. 1 is a diagram showing an overall configuration of a pump device according to the present invention, FIG. 1 (a) is a partial sectional front view, and FIG.
[Fig. 1] is a view taken along line I (b) of Fig. 1 (a).

FIG. 2 is a diagram showing an overall configuration of a pump device according to the present invention, FIG. 2 (a) is a partial sectional front view, and FIG.
FIG. 2 is a view taken along the arrow II (b) of FIG.

FIG. 3 is a diagram showing a characteristic curve of a pump device according to the present invention.

[Explanation of symbols]

 1 Pump 2 Fluid Element 3 Main Body 4 Suction Port 5 Discharge Port 6 Rotation Field Generation Nozzle 8 Ejector 9 Main Body 10 Diffuser 11 Nozzle 12 Bypass Pipe 13 Check Valve

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Keita Uei 4-2-1 Honfujisawa, Fujisawa City, Kanagawa Prefecture EBARA Research Institute

Claims (1)

[Claims] 1. A pump for pressurizing and pumping a liquid, a fluid element for suppressing the flow by giving a rotating field to the flow, and a negative pressure for generating a negative pressure at an excessive flow rate installed at a discharge port of the pump. A generator is provided, the suction port of the pump and the discharge port of the fluid element are connected, the negative pressure generator and the rotation field generating nozzle of the fluid element are connected by a bypass pipe, and the reverse pipe is connected to the bypass pipe. A pump device having a stop valve.