JP2583221Y2 - Self-priming pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION INDUSTRIAL APPLICATION The present invention relates to a self-priming pump.

2. Description of the Related Art 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, and 2 denotes a rotating shaft of the electric motor 1. 3 is an impeller casing, 4 is a priming casing, and 5 is a packing. The impeller casing 3 and the priming casing 4 are joined with a packing 5 interposed therebetween, and the packing 5 prevents water leakage to the outside.

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. 6 is a partition plate,
The packing 5 is sandwiched between the impeller casing 3 and the priming casing 4. The partition plate 6 is provided with a water circulation hole 7 and a water circulation hole 8 at predetermined positions, and a central circulation hole 9. The packing 5 is formed by the packing holes 7, 8 and the central circulation hole 9. It is configured to prevent water leakage from the surroundings. Reference numeral 10 denotes an impeller, which is housed in an impeller chamber 11 in the impeller casing. The rotary 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. Reference numeral 12 denotes a passage for allowing water to flow out of the impeller chamber 11 in the impeller casing, 13 denotes a delivery tank portion, and 14 denotes a communication passage from the delivery tank portion 13 to the impeller room 11. FIG. 8 shows the configuration of the priming casing 4. In FIG. 8, a suction passage 15 and a water tank portion 16 communicating with a water suction port are formed in the priming casing 4. Suction passage
15 communicates with the impeller chamber 11 on the side of the impeller casing through the central flow hole 9 of the partition plate 6. The water tank section 16 communicates with the delivery tank section on the impeller casing side through the through hole 7 of the partition plate 6, and communicates with the impeller chamber 11 through the through hole 8. Reference numeral 18 denotes a relaxation chamber provided between the water supply tank 13 and the communication passage 14, and has a predetermined volume. Reference numeral 19 denotes a throttle section that connects the relaxation chamber 18 and the water supply tank 13.

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, 43 denotes a self-priming pump having a suction port 41 and a discharge port 42, 44 denotes a discharge side pipe, and 45 denotes a suction side pipe.

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, water in the impeller chamber 11 is stirred by the impeller 10, and at this time, air is mixed into the water. The water containing the air enters the delivery tank 13 through the passage 12 as shown by an arrow E in FIG. Here, the water into which a part of the air is mixed flows into the communication passage 14 as shown by the arrow F.
Is returned to the impeller chamber 11 through (Note that, as shown in FIG. 7, the impeller is in a state of hanging over the communication passage.)
The water into which most of the air is mixed flows into the water tank 16 of the priming casing 4 through the flow holes 7. In the upper part of the water tank part 16 in the priming casing 4 is a steam-water separation chamber.
17 is provided, and the water flowing out of the circulation hole 7 is separated from the air in the water / water separation chamber 17, and the air is discharged from the discharge port 42 to the discharge side pipe line as shown by an arrow G in FIG. It is discharged to the water tank 40 through 44. On the other hand, the remaining water returns from the water tank section 16 to the impeller chamber 11 again through the circulation hole 8 as shown by the arrow H. 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 communication passage 14 and a part of the water from the delivery tank 13,
The water is returned to 11 (the impeller is in a state of being in the communication passage as shown in FIG. 7), and most of the water flows into the water tank 16 in the priming casing 4 through the flow hole 7. Part of the water that has flowed into the water tank portion 16 is returned to the impeller chamber 11 through the circulation hole 8, and most of the water flows into the water tank through the discharge port 42 through the discharge pipe 44. . Hereinafter, this state is referred to as a feeding state.

Problems to be Solved by the Invention FIGS. 11 and 12 show the results of vibration frequency analysis of the pump in the above-mentioned feeding state (the vertical axis shows the power spectrum of vibration, and the horizontal axis shows the rotational order ratio) and the result of frequency analysis. It is. (The vertical axis is the noise level, and the horizontal axis is the rotational order ratio.) As shown in FIG. 7, in a structure in which water is recirculated in a state where the impeller is placed on the communication passage between the delivery tank section and the impeller chamber. In the feeding state, the rotational order ratio was 6 based on the frequency analysis of the vibration shown in FIG.
Next, the twelfth, that is, the peak value of the vibration occurs at the order of 6 × n. As a result, the sixth and twelfth rotation order ratios (maximum values) are generated from the frequency analysis of the noise in FIG. 12, and the noise value increases.

Means for Solving the Problems To solve the above problems, the self-priming pump of the present invention is:
An impeller casing for accommodating an impeller, and an impeller casing provided with a delivery tank section for receiving water flowing out of the impeller chamber; a gas-liquid separation chamber communicating with the delivery tank section; A priming casing provided with a space that communicates with the separation chamber and stores priming water to be sent into the impeller chamber; and a partition plate provided between the impeller casing and the priming casing. A relaxation chamber is connected via a throttle portion, and a communication passage communicating the relaxation chamber and the impeller chamber is a peripheral wall surface on a winding start side of the impeller chamber, and a front surface of the partition plate and the impeller. It is characterized in that it is opened in the gap between the front end and the direction along the front end.

Since the communication passage communicating between the mitigation chamber and the impeller chamber is opened in the gap between the partition plate and the front end of the impeller in a direction along the front end, the feeding is performed. In this state, the water returned to the impeller chamber through the relaxation chamber does not directly touch the impeller, and pulsation is reduced. In addition, since the communication passage is provided on the peripheral wall surface on the winding start side of the impeller chamber and connected to the relaxation chamber, and the relaxation chamber is connected to the delivery tank section through the throttle section, the rotation of the impeller is performed by the relaxation chamber. The accompanying pulsation, noise, and vibration are reduced, and the self-priming can be quickly performed by the communication passage since the winding start portion of the impeller chamber is not separated from the delivery tank portion.

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. Portions having the same configuration and operation are denoted by the same reference numerals, and the description thereof will be omitted to avoid duplication. Is omitted.

FIG. 1 is a perspective view of the impeller casing 3. FIG. 2 is a view of the communication passage 14 taken along the line AA of FIG. Reference numeral 18 denotes a relaxation chamber provided between the water supply tank 13 and the communication passage 14, and has a predetermined volume. Reference numeral 19 denotes a throttle section that connects the relaxation chamber 18 and the water supply tank 13. Relaxation room during self-priming
Since the inside 18 is quickly filled with water due to the difference in specific gravity between water and air, the communication passage 14 allows quick self-priming. Since the communication passage 14 is provided in this way, a part of the water discharged from the water supply tank 13 is recirculated through the communication passage, so that the flow rate to the gas-liquid separation chamber 17 side is reduced, and the flow through the communication passage is also reduced. Due to the additional path, the resistance of the water supply tank 13 on the discharge side is reduced, the flow velocity in the water supply tank 13 is reduced, and the gas-liquid separation operation in the gas-liquid separation chamber 17 is also effectively performed. FIG. 3 and FIG. 4 show the frequency analysis result of the vibration (the vertical axis shows the power spectrum of the vibration, and the horizontal axis shows the rotation order ratio) and the noise frequency analysis result of this embodiment. (The vertical axis indicates the noise level, and the horizontal axis indicates the rotational order ratio.) As shown in FIGS. 1 and 2, the water flowing back through this portion of the communication passage 14 is different from that of FIG. 7 (conventional example). The communication passage 14 is provided on the peripheral wall surface on the winding start side of the impeller chamber 11 and has a reduced communication passage depth so that the communication passage 14 is provided in the gap between the partition plate 6 and the front end of the impeller 10. Because it is open in the direction along the front edge,
The structure is such that the impeller does not directly cross the opening of the communication passage 14. Note that the direction along the front end is a direction in which the recirculation does not go to the impeller. As a result, the impeller 10 does not drain the recirculated water to generate a large pulsation, thereby reducing noise and vibration. And this pulsation, which is small but
The pulsation, noise, and vibration from other portions caused by the rotation of the impeller 10 are guided to and absorbed by the relaxation chamber 18. Looking at the results of the frequency analysis of the vibration shown in FIG. 3, the peak value of the vibration of the 6th and 12th rotation order ratios, that is, the vibration of the 6 × n-th blade number, is smaller than the conventional example (dotted line). It can be seen that the vibration due to the rotation of is reduced. Also, as can be seen from the results of the noise frequency analysis in FIG. 4, the sixth, twelfth and A-range noise ratios are lower than those of the conventional example (dotted line). By providing the communication passage 14, the mitigation chamber 18, and the throttle section 19 in this way, it is possible to reduce noise and vibration simultaneously with the self-priming action from the delivery tank section 13 to the impeller chamber 11.

Effect of the Invention As described above, the self-priming pump of the present invention has a communication passage communicating between the relaxation chamber and the impeller chamber within the gap between the partition plate and the front end of the impeller. The water flowing back through the mitigation chamber into the impeller chamber does not directly touch the impeller in the feeding state, reducing the peak value of vibration and noise. In addition, the vibration of the self-priming pump can be reduced. Further, since the communication passage is provided on the peripheral wall on the winding start side of the impeller chamber and is connected to the relaxation chamber, and the relaxation chamber is connected to the delivery tank section through the throttle section, the rotation of the impeller is performed by the relaxation chamber. In addition to absorbing the pulsation caused by the noise, the noise and vibration can be reduced, and the relaxation chamber can be provided in the extra space between the winding start part of the impeller chamber and the delivery tank part, so that a compact configuration can be achieved. Since there is not much distance between the winding start portion and the delivery tank portion and the resistance is small, quick self-priming can be performed by the communication passage.

[Brief description of the drawings]

FIG. 1 is a perspective view of an impeller casing according to an embodiment of the present invention, FIG. 2 is an A-A view of a communication passage in FIG. 1, FIG. 3 is a view showing a frequency analysis result of vibration, FIG. FIG. 4 is a diagram showing the result of frequency analysis of noise. 5 is a diagram showing a schematic configuration of a conventional example, FIG. 6 is an exploded perspective view of the same, FIG. 7 is a perspective view of an impeller casing, FIG. 8 is a perspective view of a priming casing, and FIG. 9 is FIG. 10 is a cross-sectional view taken along the line CC, FIG. 10 is a cross-sectional view taken along the line DD in FIG. 5, FIG. 11 is a diagram illustrating a frequency analysis result of vibration, FIG. 12 is a diagram illustrating a frequency analysis result of noise, FIG. The figure is an explanatory view showing the use state of the pump. 3 impeller casing, 11 impeller chamber, 13 delivery tank section, 14 communication passage.

Claims (1)

(57) [Scope of request for utility model registration] An electric motor; an impeller fixed to a rotating shaft of the electric motor; an impeller chamber for accommodating the impeller; and a delivery tank for receiving water flowing out of the impeller chamber. An impeller casing, a priming casing provided with a gas-liquid separation chamber communicating with the delivery tank portion, and provided with a space that communicates with the gas-liquid separation chamber and stores priming water to be sent into the impeller chamber; A communication passage for connecting the mitigation chamber to the impeller chamber while the mitigation chamber is connected to the mitigation chamber via a throttle unit; Is opened in the gap between the partition plate and the front end of the impeller on the peripheral wall on the winding start side of the impeller in a direction along the front end. Features and Self-priming pump that.