JPH0734230Y2 - Magnet pump cooling device - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention is designed so that a direct current can be sequentially switched around each iron core, which is divided into a fan shape and arranged in plural in the circumferential direction, through a hall element or the like. A rotor including a stator around which a coil is energized to form a rotating magnetic field, and a plurality of permanent magnets axially opposed to the stator and having N and S poles alternately arranged in the circumferential direction. And a DC motor, and a magnet pump in which a driven magnet embedded in a pump impeller is rotated by a magnetic force by a pump driving magnet driven by the motor rotor. It is suitable.

[Conventional technology]

In a conventional magnet pump, as shown in FIG. 3, an impeller 2 arranged in a pump casing 1 made of a non-magnetic material has a plurality of fan-shaped permanent magnets 3 (for example, 8 pieces). ), N poles and S poles are alternately arranged so as to be located in the circumferential direction, and the impeller 2 is mounted on a fixed bearing 5 mounted on a casing cover 4 with a cylindrical sliding surface and a radial sliding surface. The casing 1 is rotatably supported via a rotary bearing 6 having a moving surface, and a rotary bearing 7 is attached to the end face of the suction port of the impeller 2 in a direction perpendicular to the shaft.
The axial thrust toward the suction side is supported by abutting against the fixed bearing 8 on the side.

On the other hand, on the back side (right side in the figure) of the casing cover 4, a stator 9 is held by a core cover 10 so as to abut the casing cover 4, and the stator 9
Is a plurality (for example, 6) so that each has a fan shape.
A coil 11 is wound around each of the iron cores that are divided into and arranged in the circumferential direction, and a direct current is passed through the coil 11 to form a rotating magnetic field on the end surface of the stator 9, and the permanent magnet 3 on the rotor side is formed. Is designed to rotate. The number of iron cores of the permanent magnet 3 and the stator 9 is an even number, and the numbers thereof are changed in order to reduce the attraction force acting on each other.

When the pump is in operation, by applying a direct current to the coil 11 of the stator 9, a rotating magnetic field is formed along the end surface of the stator 9, and the rotating magnetic field rotates the impeller 2 in which the permanent magnet 3 is embedded. As indicated by a thick arrow C, liquid (water) is sucked through the casing suction port 12 and discharged through the discharge port 13.

[Problems to be solved by the device]

In the conventional magnet pump described above, when the pump is in operation, the thrust load direction in the arrow A direction applied to the impeller 2 by the attractive force acting between the stator 9 made of an iron core and the permanent magnet 3 embedded in the impeller 2, and The direction of the hydraulic thrust load in the arrow B direction applied to the back surface (right side in the figure) of the impeller 2 when pumping water is opposite. Therefore, if the discharge pressure of the pump becomes low and the hydraulic thrust in the arrow B direction becomes weaker than the magnetic attraction force in the arrow A direction due to a change in the pump operating pressure, the bearing of the suction port of the impeller 2 When the amount of return (leakage) from the gap of 7 and 8 to the suction side increases, then the discharge pressure of the pump increases, and the hydraulic thrust in the above arrow B direction becomes larger than the magnetic attraction force in the arrow A direction. , The return pressure (leakage) from the gap between the suction side bearings 7 and 8 disappears, and the discharge pressure of the pump rises again, but the performance curve of the pump at this time does not return to the original trajectory, and the pump pressure − A hysteresis phenomenon occurs in the flow rate performance.

As described above, when the gap between the bearings 7 and 8 on the impeller suction side is eliminated, an impact load is applied to the bearings, and the bearings are damaged.

In order to address the above-mentioned problems, the present applicant has previously arranged the rotor made of the permanent magnets in a buried manner on the suction port side of the pump impeller, while facing the rotor and placing the stator in the pump casing. We applied for a magnet pump that was placed in the non-wetted part on the suction port side and made the axial thrust load acting on the impeller in one direction.

However, the above-mentioned magnet pump driven by the DC motor is usually manufactured only with a small output of about 300 W, and the amount of heat generated by the motor is small. Therefore, there is a problem that the motor output cannot be increased.

An object of the present invention is to provide a magnet pump capable of forcibly cooling the DC motor part to increase the output and discharging the gas having permeated the pump suction passage casing to the outside.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the invention of claim 1 forms a rotating magnetic field by winding a coil around each iron core which is divided into a fan shape and arranged in plural in the circumferential direction. And a rotor composed of a plurality of permanent magnets, which are axially opposed to the stator and have N poles and S poles alternately arranged in the circumferential direction, constitute a DC motor.
In a magnet pump that axially opposes a pump driving magnet driven by the motor rotor and rotates a driven magnet embedded in a pump impeller by magnetic force, the motor rotor and the pump driving magnet are connected to a pump suction passage. Is directly connected by a drive magnet wheel so as to form a cooling air passage between the pump magnet and the stator and the motor rotor, between the drive magnet wheel and an outer portion of the pump suction passage, and the pump drive magnet. And a pump suction casing forming a partition wall of the pump driven magnet, a cooling air passage is formed between the pump driving magnet and the pump driven magnet, and a cooling air passage is formed between the pump driving magnet and the pump driven magnet. Is attached to the pump drive magnet so as to be located at a position through which the A fan producing a forced air flow in the cooling air passage, and characterized in that attached to the motor rotor as magnetic field lines between the stator and the motor rotor is positioned at a location passing through.

[Action]

Since the present invention is configured as described above, when a coil is wound around each iron core forming a stator during pump operation, a rotating magnetic field is formed in the stator, and the rotating magnetic field causes a permanent magnet to be generated. Is rotated, and the pump drive magnet connected to the motor rotor is also rotated to rotate the driven magnet embedded in the impeller.

The rotation of both the pump-driven and driven magnets causes the impeller to rotate, sucks in the liquid, pressurizes it, and discharges it from the casing discharge port to the outside.

Further, by energizing the coil of the stator, the fan attached to the pump driving magnet or the motor rotor also rotates. Due to the rotation of the fan, cooling air is sucked from one ventilation hole of the motor casing, passes between the stator and the motor rotor, and directly connects the motor rotor and the pump drive magnet to the drive magnet wheel, and the outer portion of the pump suction passage. The cooling air cools the motor coil and the stator while passing through the space between the pump drive magnet and the pump suction casing forming the partition wall of the pump driven magnet and being discharged to the outside from the other ventilation hole. At the same time, the rotation of the pump impeller causes the gas that permeates the wall surface of the suction casing portion from the liquid passing through the pump suction casing portion and enters the motor portion to escape to the outside by the cooling air.

According to the second aspect of the invention, the cooling air flows through the cooling air passage in the opposite direction to the first aspect of the invention to cool the motor coil and the stator, and at the same time permeate the wall surface of the pump suction casing part. The gas that invades the motor,
The cooling air also allows the cooling air to escape to the outside.

〔Example〕

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

FIG. 1 is a vertical sectional view of a magnet pump showing a first embodiment of the present invention.

In the figure, the suction casing 21 made of a non-magnetic material
And a discharge casing 24, an impeller 22 is arranged in a pump chamber, and a plurality of N poles and S poles are alternately arranged in the circumferential direction on the suction port side of the impeller 22 (for example, 8 pieces). )
A pump driven magnet 23 made of a permanent magnet (not shown) is embedded, and the impeller 22 is supported by a fixed bearing 25 attached to the center of the suction casing 21 via a rotary bearing 26.

On the other hand, on the suction side of the suction casing 21, on the back surface (left side in the figure) of the suction casing 21, N poles and S poles having the same number of poles as the permanent magnets constituting the driven magnet 23 are arranged in the circumferential direction. The drive magnet 29 is attached to one side (right side in the figure) of the drive magnet ring 32 supported by the bracket 30 via the ball bearing 31, and is attached to the other side (left side in the figure) of the drive magnet ring 32. Is mounted with a motor rotor 33 which is also composed of permanent magnets in which N poles and S poles are arranged in the circumferential direction, and a stator 34 is attached to the cover 35 so as to face the motor rotor 33 in the axial direction while maintaining a narrow gap. The stator 34 is formed by winding a coil 36 around each of the iron cores, each of which is divided into a fan shape and arranged in a plurality (for example, 6) in the circumferential direction, and applies a direct current to the coil 36. A rotating magnetic field is formed to rotate the permanent magnet on the motor rotor 33 side. Going on. The central portion of the stator 34 and the drive magnet wheel 32 is formed in a hollow structure, and a suction passage (nozzle) 21a of the pump integral with the pump suction casing 21 penetrates the hollow portion.

Further, a plate-shaped fan 37 is planted in such a manner that the fan 37 is alternately arranged in the circumferential direction of the pump drive magnet 29 and is orthogonal to the boundary between the fan-shaped N and S poles in the respective radial directions. In addition, ventilation holes 38 and 39 are formed on one side in the radial direction of the cover 35 and the bracket 30, respectively, and the fan 37
The cooling air is sucked in from the ventilation hole 38 of the cover 35 by the rotation of the cover 35 and passes through the gap 32a between the outer peripheral surface of the suction passage 21a and the inner peripheral surface of the drive magnet ring 32, as shown by arrow D, for ventilation of the bracket 30 A passage for cooling air is formed so as to be discharged to the outside air from the hole 39.

Next, explaining the operation, when a direct current is applied to the coil 36 of the stator 34 during pump operation, a rotating magnetic field is formed along the end face of the stator 34, and the rotating magnetic field causes
The motor rotor 33 consisting of a permanent magnet is attached to the other side (right side in the figure)
It rotates in the same direction together with a drive magnet wheel 32 having a pump drive magnet 29 attached thereto. Due to this rotation, the pump drive magnet
The impeller 22 in which the driven magnet 23 embedded by magnetic force with 29 is embedded also rotates in the same direction to suck the liquid from the suction port 12, the pressure is increased by the impeller 22, and the casing discharge port 13 as shown by arrow C. More to the outside.

At this time, the thrust load applied to the impeller 22 by the attractive force between the permanent magnets of the pump driving magnet 29 and the pump driven magnet 23 is applied to the pump suction side as indicated by arrow a, while the impeller is pumped when pumping water. The hydraulic thrust load due to the pressure difference generated by the pressure water discharged from the outlet of the pump acting on the both side plates of the impeller is also applied to the pump suction side as indicated by the arrow B, whereby the pump blade The biaxial thrust load acting on the vehicle 22 becomes unidirectional.

Then, the axial thrust load in the one direction is applied to the pump impeller 22
Are supported by the radial sliding surfaces of the rotary bearing 26 and the fixed bearing 25, which are attached to the center of the suction port side and the center of the pump suction casing 21, respectively. The axial thrust acting between the stator 34 and the motor rotor 33 is supported by the cover 35 and the bracket 30, and does not affect the thrust load of the impeller 22.

Further, as the drive magnet 29 rotates, the pump drive magnet
The fan 37, which is positioned where the magnetic field lines between the pump 29 and the pump driven magnet 23 pass, rotates and sucks cooling air from one ventilation hole 38 that opens in the radial direction, forcibly cooling the stator, motor rotor, and bearing. Then, it is discharged to the outside through the other ventilation hole 39.

Also, during pump operation, gas that permeates the passage wall surface and enters the motor section from the liquid passing through the pump suction passage 21a,
The cooling air also allows the cooling air to escape to the outside.

According to this embodiment, the following effects are achieved.

(I) By attaching the fan 37 to the pump drive magnet 29, the DC motor composed of the stator 34 and the motor rotor 33 is operating the pump, and the rotation of the fan 37 causes the surface of the motor coil 36 and the stator 34 of the motor section. Since the cooling air is directly applied to and forcedly cooled, it is possible to efficiently cool, and thereby the output can be increased under the completely leak-free structure of the pump and the motor.

(Ii) during the operation of the pump, from the liquid passing through the pump suction passage 21a, gas that permeates the passage wall surface and enters the motor part,
It can be discharged to the outside by the forced air flow flowing through the cooling air passage including between the drive magnet wheel 32 and the outer portion of the pump suction passage 21a.

(Iii) Thrust load applied to the impeller 22 by the attractive force between the pump driving magnet 29 and the permanent magnets constituting the pump driven magnet 23, and the thrust load applied to the impeller due to hydraulic pressure difference during pump pumping. However, since both are added to the pump suction port side, the axial movement of the impeller 22 can be eliminated, so that the bearings 25 and 26 are not subjected to an impact load, and the bearings can be prevented from being damaged.

(Iv) Further, the thrust bearing sliding surface also always slides at a constant sliding gap without being affected by changes in the pump operating pressure, so that the hysteresis phenomenon of pump pressure-flow rate performance does not occur.

(V) By disposing the bearings 25 and 26 at the suction port side of the pump impeller 22 and at one position of the pump suction casing 21 that faces the suction port side, one-sided contact of the bearings is eliminated and the cost is reduced. be able to.

FIG. 2 is a longitudinal sectional view of a magnet pump according to a second embodiment of the present invention, in which the same reference numerals as those shown in FIG. 1 denote the same or like parts.

In this embodiment, plate-shaped fans 47 are planted so as to be orthogonal to the radial contact points of the fan-shaped N poles and S poles of the motor rotor 33, which are alternately arranged in the circumferential direction. This is different from the first embodiment (FIG. 1) in that

According to this embodiment, the flow direction of the cooling air is opposite to that of the first embodiment described above, the cooling air is sucked through the radial ventilation holes 39 of the bracket 30, and the drive magnet 29 and the suction casing 21 are connected. Through the gap 32a between the drive magnet wheel 32 and the suction passage 21a, and flows like the arrow E, forcibly cools the stator 34, the coil 36, and the motor rotor 33, and then is discharged to the outside air from the ventilation hole 38 of the cover 35. As a result, substantially the same operational effects as the first embodiment are achieved.

In both of the above-described embodiments, the structure in which the fans 37 and 47 are both configured by the radial plate-like member has been described, but it goes without saying that the structure is not limited to this.

[Effect of device]

As described above, according to the first aspect of the invention, the coil is wound around each iron core, which is divided into a fan shape and arranged in the circumferential direction, to form the rotating magnetic field. A DC motor is constituted by a stator and a rotor composed of a plurality of permanent magnets arranged axially opposite to the stator and having N poles and S poles arranged alternately in the circumferential direction, and is driven by the motor rotor. In a magnet pump in which a driven magnet embedded in the pump impeller is rotated by magnetic force so as to face the pump driving magnet in the axial direction, the motor rotor and the pump driving magnet are connected to the outside of the pump suction passage. Directly connected by a drive magnet wheel so as to form a cooling air passage therebetween, between the stator and the motor rotor, between the drive magnet wheel and an outer portion of the pump suction passage, and A fan that forms a cooling air passage that passes between the pump drive magnet and the pump suction casing that forms the partition wall of the pump driven magnet, and that generates a forced air flow in the cooling air passage is provided with the pump drive magnet and the pump driven magnet. By mounting the pump driving magnet so that the magnetic field lines between the magnets pass therethrough, the forced air flow flowing through the cooling air passage due to the rotation of the fan during pump operation causes the motor coil of the motor section and the stator. Cooling air directly hits the surface for forced cooling, which allows efficient cooling, which not only allows the pump and motor to have a large output under a completely leak-free structure, but also the pump. Gas that permeates the passage wall surface from the liquid passing through the suction passage and enters the motor portion is passed between the drive magnet wheel and the outer portion of the pump suction passage. By forced air flow through the non-cooling air passage can be discharged to the outside.

Further, according to the invention of claim 2, the fan for generating the forced air flow in the cooling air passage is attached to the motor rotor so as to be located at a position where a magnetic line of force between the stator and the motor rotor passes. Cooling air flows through the passage in a direction opposite to that of the above-described invention, cools the motor coil and the stator, and at the same time, the gas that permeates the wall surface of the pump suction passage and enters the motor section is cooled by the forced cooling air. Can be discharged to the outside.

[Brief description of drawings]

1 and 2 are longitudinal sectional views of a magnet pump showing first and second embodiments of the present invention, and FIG. 3 is a longitudinal sectional view of a magnet pump showing a conventional example. 21 ... Suction casing, 21a ... Pump suction passage, 22 ...
… Impeller, 23 …… Pump driven magnet, 24 …… Discharge casing, 25 …… Fixed bearing, 26 …… Rotary bearing, 29 …… Pump drive magnet, 30 …… Bracket, 32 …… Drive magnet ring, 33… …
Motor rotor, 34 …… stator, 35 …… cover, 36 ……
Coil, 37 …… fan, 38,39 …… ventilation hole, 47 …… fan.

Claims (2)

[Scope of utility model registration request] 1. A stator in which a coil is wound around a plurality of iron cores each divided into a fan shape and arranged in the circumferential direction to form a rotating magnetic field, and the stator is axially opposed to the stator. And a rotor composed of a plurality of permanent magnets provided with N poles and S poles alternately arranged in the circumferential direction constitute a DC motor, which is axially opposed to a pump drive magnet driven by the motor rotor. In a magnet pump in which a driven magnet embedded in the pump impeller is rotated by magnetic force, a cooling air passage is formed between the motor rotor and the pump drive magnet with an outer portion of the pump suction passage. Provided directly by a drive magnet wheel, between the stator and the motor rotor, between the drive magnet wheel and an outer portion of the pump suction passage, and between the pump drive magnet and the pump driven magnet. Where a cooling air passage that passes between the pump suction casing and the pump suction casing that forms the partition wall is formed, and a magnetic field line between the pump drive magnet and the pump driven magnet passes through a fan that generates a forced air flow in the cooling air passage. A cooling device for a magnet pump, wherein the cooling device is attached to the pump driving magnet so as to be located at the position. 2. A stator in which a coil is wound around a plurality of iron cores, each of which is divided into a fan shape and arranged in the circumferential direction, to form a rotating magnetic field, and the stator is axially opposed to the stator. And a rotor composed of a plurality of permanent magnets provided with N poles and S poles alternately arranged in the circumferential direction constitute a DC motor, which is axially opposed to a pump drive magnet driven by the motor rotor. In a magnet pump in which a driven magnet embedded in the pump impeller is rotated by magnetic force, a cooling air passage is formed between the motor rotor and the pump drive magnet with an outer portion of the pump suction passage. Provided directly by a drive magnet wheel, between the stator and the motor rotor, between the drive magnet wheel and an outer portion of the pump suction passage, and between the pump drive magnet and the pump driven magnet. A fan that forms a cooling air passage that passes between the pump suction casing and the pump suction casing that forms the partition wall and that generates a forced air flow in the cooling air passage is located at a position where the magnetic field lines between the stator and the motor rotor pass. A cooling device for a magnet pump, wherein the cooling device is attached to the motor rotor.