JPH0126265B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a pump device in which an impeller and a rotor of an electric motor are integrally provided within a casing.

[Prior Art] Attempts have been made to simplify the structure of a small-sized pump device by integrally forming an impeller on the rotor of a motor serving as a power source.

However, even if the structure is simplified when the rotor and impeller are integrated, water in the casing reaches the outer periphery of the rotor, so it is necessary to make the inner periphery of the motor stator waterproof.

Although such a configuration simplifies the structure of the pump portion including the impeller, it becomes necessary to insulate the inner periphery of the stator of the electric motor because water intrudes into the inner periphery of the stator.

Such insulation around the inner periphery of the stator increases the gap between the stator and the rotor, which has the problem of deteriorating the operating efficiency of the motor.

Furthermore, when the gap between the stator and rotor becomes large, a problem arises in that in electric motors equipped with a rotor made of magnets, magnetic flux leaks between different poles of the stator, resulting in a reduction in torque.

In other words, the air gap formed between the stator and rotor is a decisive factor regarding the operating efficiency of an electric motor, but when a rotor consisting of a two-pole magnet is combined with a stator consisting of three poles. And the magnetic flux of the stator to the rotor may flow to different poles of the stator which do not affect the torque of the rotor.

[Problems to be solved by the invention] Therefore, the distance between the stator poles and the rotor magnetic poles has an effect on the torque, so the stator magnetic poles are lengthened in the circumferential direction to oppose the rotor. If the area is increased, the torque may decrease rather than improving the magnetic effect, and there is a phenomenon in which the improvement does not progress.

Under such circumstances, in pumps where the rotor is integrated with the impeller and the rotor is submerged in water, an insulator or the like is interposed between the stator and the rotor, and the tips of the teeth that become the magnetic poles of the stator are Since the distance between the stator and the yoke of the magnet, which becomes the magnetic pole of the rotor, becomes large, a problem arises in that the magnetic flux of the stator does not act efficiently on the rotor.

In view of these circumstances, the present invention provides a structure for this type of pump device in which the magnetic flux of the stator acts on the rotor to obtain sufficient torque, thereby obtaining an efficient pump device. It is an object.

[Means for Solving the Problems] The present invention provides a pump casing that is provided to seal the inner periphery of a stator of an electric motor, a magnet rotor of the electric motor that rotates within the casing, and a magnet rotor that rotates within the casing. A mold layer having a yoke on the inner periphery and integrally sealing the outer periphery, and an impeller provided on the rotor, and the effective distance t between different poles of the tooth tips of the stator is set such that t>inside the stator. The problem is solved by setting the distance from the circumferential surface to the outer circumferential surface of the rotor's yoke to be x2.

[Function] The magnetic flux flowing from the inner peripheral surface of the tooth tips of the stator to the outer peripheral surface of the rotor yoke has less magnetic resistance than the magnetic flux flowing between the tooth tips of different polarities of the stator, and the stator and rotating The magnetic flux that contributes to the torque with the child increases.

Therefore, even if the inner circumference of the rotor and the outer circumference of the rotor are covered with a casing and a mold layer, respectively, and the gap becomes large, leakage of magnetic flux between different poles of the stator is reduced, and the rotor has a large torque can be obtained.

[Example] The present invention will be described based on an example shown in the drawings.

FIG. 1 is a longitudinal cross-sectional view showing the structure of a pump device according to the present invention, FIG. 2 is a partial cross-sectional view showing the arrangement relationship between a stator and a rotor that constitute a motor part, and FIG. It is a partially enlarged view.

Moreover, FIG. 4 is a diagram showing another embodiment.

In the figure, 1 is the stator of the electric motor, and 3
The yoke portion of each slot 3 of the iron core 2 formed in the slot is provided with a winding 4 made of a coil wound in an annular shape, and is made of a resin material such as Primics so as to be integrated with the frame 5. It is molded into.

The inner circumference of the stator 1, that is, the inner circumference formed by the inner circumference of the tooth tips 6 of the iron core 2, is sealed with a cylindrical part of a casing 7 made of water-resistant resin, and the inside of the casing 7 is sealed. The structure is such that the water filled in the coil 4 does not leak into the live parts such as the winding 4.

A rotor 8 is disposed inside the casing 7 so as to face the stator 1 .

The rotor 8 is a magnetic rotor equipped with a cylindrical magnet 9. A cylindrical yoke 10 made of mild steel is provided in close contact with the inner periphery of the magnet 9, and the inner and outer peripheries are made of Zylon. It is integrally molded with resin such as.

Therefore, the outer circumferential surface of the magnet 9 is sealed by the mold layer 11 and subjected to rust prevention treatment.

A shaft 12 fixed to the casing 7 passes through the center of rotation of the rotor 8.
is rotatably supported on the shaft 12 via a bearing 13.

An impeller 14 is integrally formed on the pump side of the rotor 8, and by rotating the rotor 8 within the casing 7, water sucked in from the suction port 15 by the impeller 14 is transferred to the discharge port. It is configured to discharge from 16.

In addition, the effective distance t between different poles of the respective tooth tips 6 of the iron core 2 constituting the stator 1 is determined by the thickness of the caning 7 being a, the thickness of the mold layer 11 being b, and the thickness of the casing 7 and the mold layer 11 being a. If the thickness of the magnet 9 is c and the thickness of the magnet 9 is d, then t>(a+b+c+d)×2.

Here, (a+b+c+d) is the distance from the inner circumferential surface of the tooth tips 6 of the stator 1 to the outer circumferential surface of the yoke 10 of the rotor 8.

By determining the effective interval t between the different poles of the tooth tips 6 in this way, it is possible to prevent magnetic short circuit between the tooth tips 6 and rotate the rotor 8 with the torque necessary for pump operation. It is possible.

That is, when the impeller 14 is formed integrally with the rotor 8 as in the present invention, and the rotor 8 is rotationally driven within the casing 7 filled with water, the rotation It was necessary to obtain a large rotational torque without forming a live part in the child 8, and for this purpose a magnet rotor using the magnet 9 was formed, but the thickness of the magnet 9 became considerably large. thing,
and the inner circumference of the stator 1 is sealed with a casing 7,
Moreover, since the outer periphery of the magnet 9 is sealed with the mold layer 11, the substantial air space is greatly expanded, and the magnetic resistance in the magnetic circuit of the motor portion becomes extremely large.

Therefore, the magnetic flux generated by the winding 4 is likely to be short-circuited between the tooth tips 6 of different poles, and if the magnetic flux of the winding 4 and the magnetic flux of the magnet 9 are no longer interlinked, rotational torque is generated. pump function.

For this purpose, the effective distance t between the tooth tips 6 is set as t>
(a + b + c + d) x 2, and furthermore, the shape of the tooth tip 6 is such that the magnetic flux density is equal to or higher than the saturation region.For example, as shown in FIG. 4, the iron core 2 is formed of a steel plate. In this case, the actual distance between the tooth tips 6 can be narrowed by increasing the magnetic resistance between the tooth tips 6 by setting it to about 20,000 Gauss or more.

That is, the tooth tip portion 6 is connected to the yoke 10 of the rotor 8.
The problem is the position in the circumferential direction with respect to the mechanical position, and it is sufficient if the dimensions are substantially satisfied magnetically with respect to the mechanical position.

Therefore, it is only necessary that the effective distance t between different poles is substantially satisfied, and if the magnetic resistance increases due to a decrease in the cross-sectional area, the effective distance t between different poles becomes substantially larger. It means I'm getting old.

Furthermore, although the magnet 9 itself has the power to generate magnetic flux, the magnetic resistance when the magnetic flux flows from the tooth tips 6, 6a to the yoke 10 is the same as that of air, and is different from the tooth tips 6, 6a. Regarding the effective distance t between the poles, the amount of magnetic flux flowing is determined by which direction the distance from the tooth tips 6, 6a is smaller.

Therefore, it is sufficient that the distance between the yoke 10 and the tooth tips 6, 6a is substantially smaller than the effective distance t between different poles.

On the other hand, with respect to the casing 7, the same effect can be obtained by integrally molding the portion that seals the inner periphery of the stator 1 with the stator 1.

[Effects of the Invention] As explained above, according to the present invention, a pump device that has a simple structure, is small, lightweight, and can be manufactured at low cost can be obtained.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view showing the structure of a pump device according to the present invention, FIG. 2 is a partial cross-sectional view showing the arrangement relationship between a stator and a rotor that constitute a motor part, and FIG. It is a partially enlarged view. Moreover, FIG. 4 is a diagram showing another embodiment. 1...Stator, 2...Iron core, 6...Tooth tip, 7
... Casing, 8 ... Rotor, 9 ... Magnet, 11 ... Mold layer, 14 ... Impeller.

Claims (1)

[Scope of Claims] 1. A pump casing provided to seal the inner periphery of a stator of an electric motor, a rotor equipped with a magnet of the electric motor that rotates within the casing, and a yoke attached to the inner periphery of the magnet. and an impeller provided on the rotor, and an effective distance t between different poles of the tooth tips of the stator is determined as follows. pump equipment. t>distance from the inner circumferential surface of the stator to the outer circumferential surface of the rotor yoke×2 A pump device according to claim 1, characterized in that: