JPH1182357A - Cylinder type magnet pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To discharge air around an impeller and to prevent the generation of the abnormal sound in a cylinder type magnet pump which utilizes the magnetic bonding power of the cylindrical magnet as a power transmitting means for delivering liquid. SOLUTION: In a cylinder type magnet pump where a by-pass hole 17 is formed between a thinned part 13 of an impeller 8 and an impeller water passage face 15, a circulated water circuit flowing from the thinned part 13 toward the impeller water passage face 15 through by-pass hole 17 by the difference in pressure between an inlet part 19 and a discharge part 18 in the operation of the pump, is formed. Whereby air stored in the thinned part 13 can be easily discharged with the circulated water flowing in the circuit of the circulated water flowing from the thinned part 13 toward the impeller water passage face 15, and the generation of the abnormal sound can be inhibited.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylinder type magnet pump for sending a liquid by using a magnetic coupling force of a cylindrical magnet as a power transmission means.

[0002]

2. Description of the Related Art In general, cylinder type magnet pumps are widely used as circulation pumps for hot water supply and heating. Particularly, unlike a mechanical seal system, a heating pump that requires a long-time operation is an indispensable pump because there is no water leakage even at the end of life.

Conventionally, this type of cylinder type magnet pump has a configuration as shown in FIG. Less than,
The configuration will be described with reference to the drawings.

As shown in the figure, a shaft 1 of an electric motor
A housing 2 that rotates with the rotation of the shaft 1 is attached, and a cylindrical driving magnet 3 is fixed inside the housing 2. The pump casing 14 and the separation plate 6 are attached to the bracket 5 covering the housing 2 in a state where the pump casing 14 and the separation plate 6 are sealed by an O-ring 7. A shaft 9 fixed between the pump casing 14 and the separation plate 6 is provided with a D-cut structure for preventing rotation, and the shaft 9 has a blade that rotates following the rotation of the housing 2. Car 8 is attached.

[0005] Inside the impeller 8, a driven magnet 4 is provided.
Is fixed, and the driven magnet 4 is
And a pair with the driving magnet 3 through the magnetic field. The driven magnet 4 is slightly displaced from the driving magnet 3 in the direction opposite to the motor, and the driven magnet 4 is separated from the housing 2 holding the driving magnet 3 via the separation plate 6 with a small force. The held impeller 8 is in the attracted state.

The driven magnet 4 fixed inside the impeller 8 has a thick resin portion between the driven magnet 4 and the impeller water passage surface 15 due to the structure of the parts. In order to prevent this, a meat stealing portion 13 is provided.

At the center of the impeller 8, a bearing 10 corresponding to the shaft 9 is provided. A first bearing plate 11 and a second bearing plate 12 provided with a D-cut structure are provided corresponding to both end surfaces of the bearing 10, and the bearing 10 rotates integrally with the impeller 8. , The first bearing plate 11 and the second bearing plate 1
2 slides. The first bearing plate 11 and the second bearing plate 12 are fixed while being inserted into the shaft 9.

The total length of the bearing 10 fixed to the center of the impeller 8 is the sliding end face of the first bearing plate 11 and the second bearing plate 12.
Is slightly shorter than the distance from the sliding end face, and a thrust allowance A is provided. This is to prevent the impeller 8 from being locked due to the accumulation of the dimensional tolerance of each part and the variation at the time of assembling.

When the pump is stopped, the driving magnet 3 fixed to the housing 2 and the impeller 8
The impeller 8 is attracted to the separation plate 6 side by the attractive force due to the magnetic coupling with the driven magnet 4 fixed to the motor, and the motor-side bearing sliding surface 10b of the bearing 10 and the second bearing plate 1
2 is in contact with the sliding surface.

Next, the operation of the cylinder type magnet pump will be described. When the motor is operated, the housing 2 to which the drive magnet 3 is fixed rotates with the rotation of the shaft 1. Following this rotation, the impeller 8 to which the driven magnet 4 magnetically coupled to the driving magnet 3 is fixed rotates, and the circulating water is sucked in the direction B. At this time, the impeller 8, which has been attracted to the separation plate 6 by the magnetic coupling force between the driving magnet 3 and the driven magnet 4, becomes a thrust margin A of the impeller 8 due to a pressure difference between the suction side and the discharge side. And the sliding surface of the first bearing plate 11 and the bearing sliding surface 10a on the side opposite to the motor are rotated and slid. Then, a gap is formed between the second bearing plate 12 and the motor-side bearing sliding surface 10b by the thrust allowance A.

[0011]

In the cylinder-type magnet pump having the above-described structure, when circulating water is introduced into the pump chamber to operate the pump first in the initial state, air remains in the pump chamber. When the pump is operated in this state, air is discharged together with the circulating water from the discharge port to some extent, but some of the air is entangled around the impeller meat stealing portion 13 due to centrifugal force and rotates together with the impeller 8 to operate. When the air enters the pump chamber during operation for some reason, the entanglement of the air further increases, and an abnormal sound is generated.

As shown in FIGS. 7 and 8, the provision of the ribs 16 on the robbing portion 13 improves the air discharge to some extent. That is, with the rotation of the impeller 8, the air entangled with the meat stealing part 13 is initially diffused by the ribs 16 and is discharged together with the circulating water. However, if all the air cannot be discharged in the beginning, the air simply rotates together with the impeller 8 and is not discharged. Therefore, all the air can be discharged by repeating the ON / OFF of the pump several times.

The number of the radial ribs 16 is about four, as shown in FIG. 7, since the gap between the ribs 16 is wide, the mass of air is too large and the air cannot be dispersed as a result.
Since the number of ON / OFF repetitions of the pump is increased or all the air cannot be completely removed, it has been experimentally found that at least about eight pumps are necessary as shown in FIG.

However, the addition of the eight ribs 16 increases the mold release and the slide portion of the mold and increases the mold size, so that the mold cost and the product unit price also increase.
Also, due to the pump design, the pump casing 14 and the impeller 8
When the gap E with the outer diameter is small, no matter how much the radial ribs 16 are added to the meat stealing portion 13, the air is very difficult to escape, resulting in an abnormal sound.

SUMMARY OF THE INVENTION An object of the present invention is to provide a cylinder type magnet pump capable of bleeding air with a simple structure while taking the above conventional problems into consideration.

[0016]

In order to achieve this object, a cylinder type magnet pump according to the present invention has a structure in which a bypass hole is provided between a robbing portion of an impeller and an impeller water passage. .

According to the present invention, in the initial state, air can be easily discharged by operating the pump once, and air can be discharged even if air is supplied into the pump chamber for some reason during operation. And the occurrence of abnormal sound can be suppressed.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is directed to a separation plate for partitioning a pump chamber and an electric motor section, a fixed shaft provided inside the pump chamber, and a rotatable rotation of the fixed shaft. A supported impeller, a cylindrical driven magnet provided inside the impeller, and a cylindrical driving magnet provided on the electric motor and paired with the driven magnet and located on the outer ring. A cylinder type magnet pump having a bypass hole between a space existing between the shroud on the rear surface of the impeller and the driven magnet and a water passage portion of the impeller. The abnormal noise is eliminated by discharging the air that has passed through the bypass hole early, and the mold structure is simple.
Further, since the size of the mold can be reduced, there is an effect that the cost of the mold and the unit price of the product can be reduced.

According to a second aspect of the present invention, there is provided a cylinder type magnet pump according to the first aspect, wherein
The bypass hole provided in the impeller has a configuration in which only the edge portion on the water passage side is chamfered, and when the circulating water flows out to the water passage surface via the bypass hole, the impeller rotates. Cavitation is likely to occur at the edge,
The chamfer has an effect of suppressing the occurrence of the cavitation.

Hereinafter, an embodiment of a cylinder type magnet pump according to the present invention will be described with reference to the drawings.

(Embodiment 1) FIG. 1 is a sectional view of a cylinder type magnet pump according to Embodiment 1 of the present invention, and FIG.
2 is a sectional view taken along line FF in FIG. 1, and FIG.
It is G sectional drawing.

In the drawings, the same components as those in the conventional example are denoted by the same reference numerals. The feature of the first embodiment lies in the impeller 8 in the cylinder type magnet pump. As shown in FIGS. 1 to 3, the impeller 8 is located between the meat steal part 13 and the impeller water passage surface 15. Bypass hole 1
7 is provided. The other components are the same as those of the conventional example, and the description is omitted.

In the cylinder type magnet pump having the above-described structure, when the pump is operated, the impeller 8 rotates and performs a pumping operation. Generates a positive pressure. Thereby, the circulating water is supplied to the suction port 19.
From the discharge port 18 via the impeller water passage surface 15. At this time, before and after the bypass hole 17, the impeller water passage surface 15 side has a negative pressure, and the meat stealing portion 13 side has a positive pressure. Therefore, near the bypass hole 17,
The circulating water flows from the third side toward the impeller water passage surface 15 side, most of which proceeds to the outer periphery 20 of the impeller and is discharged from the discharge port 18. Further, a part of the leakage proceeds from the meat stealing portion 13 to the bypass hole 17 again. Thereby, the meat stealer 13
The lump of air collected in the vicinity travels to the impeller water passage surface 15 side via the bypass hole 17 together with the circulating water, and is discharged to the discharge port 1.
Emitted from 8.

With respect to the diameter of the bypass hole 17, if the hole is too large, the above-mentioned leakage increases, and the pump performance is disadvantageously lost. In the case of a pump having an output of about 60 W class or less, it is preferable to set the diameter to about φ1 to φ2 and to arrange the pump symmetrically with respect to the center of the impeller. Also, the number is suitably two or four.

(Embodiment 2) FIGS. 4 and 5 show an impeller of a cylinder type magnet pump according to Embodiment 2 of the present invention, FIG. 4 is a sectional view taken along line FF in FIG. 1, and FIG.
FIG.

In the cylinder type magnet pump provided with the impeller 8 having the bypass hole 17, when air and circulating water flow to the impeller water passage surface 15 side via the bypass hole 17, the rotation of the impeller 8 Cavitation is likely to occur at the edge of the bypass hole 17 due to the action.

Therefore, in the second embodiment, as shown in FIGS. 4 and 5, a chamfered portion 17a is formed at the edge of the bypass hole 17 on the impeller water passage surface side. This chamfer 17a
Is formed over the entire periphery of the edge of the bypass hole 17 on the impeller water passage surface side, or has a chamfered shape along the flow of circulating water.

With this configuration, when air and circulating water flow out to the impeller water passage surface 15 side via the bypass hole 17, it is possible to suppress the occurrence of cavitation in the bypass hole 17 of the impeller 8.

[0029]

As is apparent from the above description, the cylinder type magnet pump of the present invention has the bypass hole between the meat rotting portion of the impeller and the water passage surface of the impeller. The air that accumulates in the water can be easily discharged together with the circulating water due to the pressure difference caused by the pump action, and has the effect of suppressing the occurrence of abnormal noise.

[Brief description of the drawings]

FIG. 1 is a sectional view of a cylinder type magnet pump according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line FF in FIG.

FIG. 3 is a sectional view taken along line GG in FIG. 2;

FIG. 4 is a sectional view of an impeller according to a second embodiment of the present invention.

FIG. 5 is a sectional view taken along line HH in FIG. 4;

FIG. 6 is a sectional view of a conventional cylinder type magnet pump.

7 is a sectional view taken along the line CC in FIG. 6;

FIG. 8 is a sectional view of another conventional impeller.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 shaft 2 housing 3 drive magnet 4 driven magnet 5 bracket 6 separator 7 O-ring 8 impeller 9 shaft 10 bearing 10a non-motor-side bearing sliding surface 10b motor-side bearing sliding surface 11 first bearing plate 12th Second bearing plate 13 Stealth portion 14 Pump casing 15 Impeller water passage surface 16 Rib 17 Bypass hole 17a Chamfered portion 18 Discharge port 19 Suction port 20 Impeller outer periphery 21 Rear shroud

Claims (2)

[Claims] 1. A separation plate separating a pump chamber and an electric motor unit, a fixed shaft provided inside the pump chamber, an impeller rotatably supported by the fixed shaft, and an impeller provided inside the impeller. And a driven magnet provided in the electric motor, a pair of the driven magnet and a cylindrical driving magnet positioned on the outer ring, and provided between the impeller rear shroud and the driven magnet. A cylinder type magnet pump having a bypass hole between an intervening space and an impeller water passage. 2. The cylinder type magnet pump according to claim 1, wherein only a water passage side edge of the bypass hole provided in the impeller is chamfered.