JP2881950B2 - Self-priming pump - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a self-priming pump having a configuration in which an impeller having a plurality of blades is disposed in an impeller casing.

2. Description of the Related Art In general, a self-priming pump has an impeller casing for accommodating an impeller, and a priming tank for supplying priming water in the impeller casing. FIG. 5 shows an example of this type of self-priming pump. In FIG. 5, reference numeral 1 denotes an electric motor. An impeller casing 3 is attached to one side of the electric motor, and a rotating shaft 2 of the electric motor 1 is connected to an impeller (not shown) in the impeller casing 3. A priming casing 4 is provided on the open side of the impeller casing 3 through a packing 5.
Are combined.

FIG. 6 is an exploded perspective view. As shown in FIG. 6, the impeller casing 3 and the priming casing 4 have both openings facing each other. The partition plate 6 and the packing 5 are sandwiched between the impeller casing 3 and the priming casing 4. The partition plate 6 is provided with water flow passages 7 and 8 at predetermined positions, and a central flow hole 9 at a predetermined position. The packing 5 is provided with these flow holes 7 and 8 and the central flow hole. 9 is configured to prevent water leakage from the periphery. Further, an impeller 10 is accommodated in an impeller chamber 11 in the impeller casing. The rotating shaft 2 is inserted into the center of the impeller chamber 11, and the impeller 10 is mounted at the tip of the impeller chamber 11 with a mechanical seal sandwiched therebetween.

FIG. 7 shows the configuration of the impeller casing 3. The impeller casing 3 has an impeller chamber 11, and a passage 12 for flowing water from the impeller chamber 11 to the delivery tank 13.
And a communication passage 14 from the delivery tank section 13 to the impeller chamber 11 is provided.

FIG. 8 shows the configuration of the priming casing 4. As shown in FIG.
A suction channel 15 and a water tank 16 communicating with 41 are formed. The suction passage 15 is provided in the central flow hole 9 of the partition plate 6 shown in FIG.
Thereby, it communicates with the impeller chamber 11 on the impeller casing side. Further, the water tank 16 communicates with the delivery tank on the impeller side through the flow hole 7 of the partition plate 6.
As a result, communication with the impeller chamber 11 is established. In the figure, reference numeral 17 denotes a steam-water separation chamber, and reference numeral 42 denotes a discharge port.

FIG. 13 is an explanatory diagram showing a state in which the self-priming pump is used to circulate water in a water tank. In FIG. 13, reference numeral 40 denotes a water tank, and reference numeral 43 denotes a self-priming pump having a suction port 41 and a discharge port 42. The self-priming pump is connected to the water tank 40 by a discharge pipe 44 and a suction pipe 45.

Next, the operation will be described. First, priming water is injected into the priming casing 4 in advance. The water injected into the priming casing 4 enters the impeller chamber 11. Next, when the electric motor 1 is driven, the impeller 10 in the impeller chamber 11 rotates.
Then, the water in the impeller chamber 11 is stirred by the impeller 10, and at this time, air is mixed into the water. The water mixed with air enters the delivery tank 13 through the discharge passage 12 as shown by the arrow a in FIG. Here, the water into which a part of the air is mixed flows through the communication passage 14 into the impeller chamber 11 as shown by the arrow b. Most of the water mixed with air passes through the flow holes 7 of the partition plate 6 and
It flows into the water tank 16 of the priming casing 4 shown in FIG. An air / water separation chamber 17 is provided above the water tank section 16 in the priming casing 4, and water flowing out of the circulation holes 7 of the partition plate 6 is separated from the air in the air / water separation chamber 17,
The air is discharged from the discharge port 42 to the water tank 40 through the discharge side pipeline 44 as shown by an arrow c in FIG. On the other hand, the remaining water returns from the water tank portion 16 to the impeller chamber 11 of the impeller casing 3 through the flow hole 8 of the partition plate 6 as shown by the arrow d. That is, the water circulates between the impeller chamber 11 and the water tank section 16, and only the air flows out. When this state continues, the air pressure gradually decreases in the central portion of the impeller chamber 11 and the suction passage 15. Then, the water in the water tank 40 is sucked up by the pressure difference between the pressure in the suction passage 15 and the outside. Water in the water tank 40 is drawn from the suction port 41 to the suction passage.
After flowing into the impeller chamber 11 and further into the impeller chamber 11, the state shifts to a full-fledged water supply state.

The sucked water passes through the discharge passage 12 and is delivered to the delivery tank 13
Part of the water from the delivery tank 13 is returned to the impeller chamber 11 through the communication passage 14.

At this time, as shown in FIG. 7, when the tip e of one impeller 10 passes through the tip of the discharge passage 12, the tip f of the other impeller 10 does not pass through the communication passage 14. Most of the water flows into the water tank 16 in the priming casing 4 through the flow holes 7 of the partition plate 6. Part of the water that has flowed into the water tank portion 16 is returned to the impeller chamber 11 through the flow holes 8 of the partition plate 6, and most of the water flows from the discharge port 42 through the discharge pipe 44 to the water tank.
Flow into 40. Hereinafter, this state is referred to as a feeding state.

Problems to be Solved by the Invention FIGS. 11 and 12 show the vibration frequency analysis results of the pump in the above-mentioned feeding state (the vertical axis shows the power spectrum of vibration, and the horizontal axis shows the rotation order ratio) and the frequency analysis results. (The vertical axis is the noise level, and the horizontal axis is the rotational order ratio). In the conventional configuration as described above, in the feeding state, the vibration frequency analysis shown in FIG. As a result, according to the noise frequency analysis shown in FIG. 12, the sixth and twelfth rotation order ratios (maximum values) are generated, and the noise value increases.

SUMMARY OF THE INVENTION An object of the present invention is to provide a low-vibration, low-noise self-priming pump, taking the above conventional problems into consideration.

Means for Solving the Problems In order to solve the above problems, the present invention solves the above problem, at the same time that the tip of one blade passes through the outflow passage opening in the impeller chamber of the impeller casing, and the tip of the other blade is The configuration is such that there is a relationship between positions passing through a passage communicating with the impeller chamber.

Operation With the above configuration, the impact when the blade tip of the impeller passes through each passage in the impeller chamber occurs at the same time, and the phase of the pulsating flow coincides, and the flow of water becomes smooth. The impact on the impeller casing is reduced.

Embodiment Hereinafter, a self-priming pump according to an embodiment of the present invention will be described. The basic configuration of the self-priming pump according to this embodiment is the same as that shown in the above-described conventional example, and components having the same configuration and operation are denoted by the same reference numerals, and the Description is omitted.

FIG. 1 is a perspective view of an impeller casing, and FIG. 2 is a plan view of the impeller casing. 3 and 4 show the vibration frequency analysis results (the vertical axis represents the vibration power spectrum and the horizontal axis represents the rotation order ratio) and the noise frequency analysis results (the vertical axis represents the noise level and the horizontal axis represents the present embodiment). The rotation order ratio). As shown in FIG. 2, the characteristic configuration of the present embodiment is that one blade tip e of the impeller 10 passes through the inlet of the outflow passage 12 and the other blade tip f is
The blades have a mutual blade positional relationship such that they pass through a passage 14 communicating with the blade wheel chamber 11.

In the above configuration, the tip of each of the two blades has a passage 14 communicating the inlet of the outflow passage 12, the delivery tank portion, and the impeller chamber.
At the same time, the outflow and inflow phases of the inlet of the outflow passage 12 and the passage 14 coincide with each other, that is, the phases of the pulsating flows coincide with each other, resulting in a smooth flow. The impact given to 3 is reduced, and the noise is reduced.

This is clear from the vibration frequency analysis results shown in FIG. 3, that is, the peak values of the sixth and twelfth rotation orders are smaller than those of the conventional example (dotted line). In addition, as the peak value of the vibration is reduced as described above, the sixth, twelfth and A-range noise values of the rotational order ratio are reduced from the result of the noise frequency analysis of FIG. 4 as compared with the conventional example (dotted line).

Advantages of the Invention As is clear from the above description of the embodiment, the self-priming pump of the present invention has a structure in which the tip of one impeller passes through the outflow passage port and the tip of the other impeller is connected to the delivery tank. By passing through the passage communicating with the impeller chamber, the impact when the tip of the blade passes through the passage is generated at the same time, the flow of water becomes smoother, the impact is reduced, and the pump is reduced in vibration and noise. It has an excellent effect that it can be done.

[Brief description of the drawings]

1 is a perspective view of an impeller casing according to one embodiment of the present invention, FIG. 2 is a plan view of the same, FIG. 3 is a vibration power spectrum characteristic diagram, FIG. 4 is a noise level characteristic diagram, and FIGS. 12 shows a conventional example, FIG. 5 is a cross-sectional side view of a conventional self-priming pump, FIG. 6 is an exploded perspective view of the essential parts, FIG. 7 is a perspective view of an impeller casing, and FIG. FIG. 9 is a perspective view of the priming casing, FIG. 9 is a cross-sectional view taken along line CC of FIG. 5, FIG. 10 is a cross-sectional view taken along line DD of FIG. 5, FIG. The figure is a noise level characteristic diagram, and FIG. 13 is a schematic configuration showing a pump operating state. 3 impeller casing, 10 impeller, 12 discharge passage, 13 discharge tank section, 14 communication passage.

Claims (1)

(57) [Claims] 1. An electric motor, an impeller fixed to a rotating shaft of the electric motor, an impeller chamber accommodating the impeller, an outflow passage through which water flowing out of the impeller chamber passes, and receiving the outflow water. An impeller casing having a delivery tank section, a passage communicating the delivery tank section with the impeller chamber, a steam / water separation chamber communicating with the delivery tank section, and communicating with the steam / water separation chamber, the impeller chamber And a priming casing for storing priming water for sending to the impeller, and at the same time the tip of one of the impellers of the impeller passes through the inlet of the outflow passage, and the tip of the other impeller passes through the passage communicating the delivery tank section and the impeller chamber Self-priming pump with blades positioned relative to each other.