JPH02269432A - Brushless blower motor - Google Patents

Abstract

PURPOSE:To reduce the temperature rise of the respective sections of a motor by forming a plurality of recessed-section-shaped channels for composing a ventilation flue on the inner peripheral section of a bracket for retaining the outer periphery of a circular stator core, and between the inner peripheral section and the outer periphery of the stator core. CONSTITUTION:On the inner peripheral section of a bracket B8 for retaining stator core 9, a plurality of recessed-section-shaped channels 10 for composing a ventilation flue between the inner peripheral section and the outer periphery of the stator core 9 along the axial direction are formed. An air current to be generated by the centrifugal type fan 1 of high-speed rotation with a driving motor 2 is spread by an air guide 6, and at the same time, is peripheral penetrated through a space between the stator core 9 and the rotor 11 of a permanent magnet, and another part is exhausted to an external section through the recessed-section-shaped channel 10. As a result, the temperature rise of the respective sections of the motor 2 can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a brushless blower motor used in vacuum cleaners and the like.

BACKGROUND ART Conventionally, this type of blower motor has used a commutator motor, and the stator has a rectangular stator core 25 as shown in FIG. 2(b). The outer shape of the stator core is press-fitted into the bracket 26 and held there. As shown in FIG. 2(a), airflow entering from the intake hole 23 of the fan casing 22 due to the rotation of the centrifugal fan 21 is formed between the rotor 24 and the stator core 25 and between the stator core 25 and the bracket 26. The liquid was discharged to the outside through a gap 27.

Problems to be Solved by the Invention However, since the conventional commutator motor has a brush 28, the motor life is determined by the brush life, and the problem is that noise is generated due to the sliding between the brush and the commutator. Studies are underway to extend life and reduce noise, and the use of brushless motors is being considered. However, brushless motors generally use a stator core with a round shape due to characteristics and cost considerations.
When this stator core is attached to a cylindrical bracket like a conventional commutator motor, the airflow guided from the air guide only passes through the gap between the rotor 24 and the stator core 25 (the exhaust hole of the bracket 26). There was a problem that the stator windings were not discharged smoothly, resulting in a decrease in vacuum pressure, a decrease in efficiency, and an increase in the temperature of the stator windings.

The present invention solves these problems by providing a brushless blower motor that achieves high vacuum pressure, high efficiency, and reduces temperature rise in various parts of the motor.

Means for Solving the Problems The present invention solves this problem by adding a layer to the outer periphery of the stator core on the inner periphery of the bracket that inscribes the stator core in order to smoothly guide the airflow coming in from the intake hole to the exhaust hole. A plurality of concave-shaped grooves are formed to form ventilation passages between the two.

With this configuration, when the airflow flowing in from the intake hole passes through the air guide and is discharged from the motor exhaust hole, the recess-shaped groove of the bracket acts as a passage for the airflow, making the discharge smooth.

EXAMPLE Hereinafter, an example of the present invention will be described based on FIG.

A fan 1 is coupled to a shaft 3 of a driving brushless motor 2,
A fan unit with a fan casing 5 having an air intake hole 4 in the center and an air flow flowing in through the air intake hole 4 guided into the inside of the motor 2 (and an air guide 6 fixed to a bracket A7) is fixed to a bracket B8. A plurality of recess-shaped grooves 10 are formed along the axial direction on the inner circumference of the bracket B8 that holds the stator core 9, and form ventilation passages between the bracket B8 and the outer circumference of the stator core 9. An opening is provided.

Next, to explain the operation of this embodiment, the airflow generated by the centrifugal fan 1 that is rotated at high speed by the drive motor 2 is gradually spread by the air guide 6, and a part of the airflow is transferred to the stator core 9 and the rotor made of permanent magnets. 11, and a part of it passes through the recess-shaped groove 10 and is discharged to the outside from the opening.

As described above, the present invention reduces the resistance of the airflow when passing through the exhaust passage by forming the recessed groove 10, thereby smoothly exhausting the air.

Effects of the Invention As described above, according to the present invention, the exhaust efficiency is improved, a high vacuum degree and high efficiency are obtained, and the motor is effectively cooled, so that it is effective in improving the characteristics of the motor, and its practical effects are There is something big.

[Brief explanation of drawings]

FIG. 1(a) is a half-sectional view of an electric blower showing an embodiment of the present invention, FIG. 1(b) is a view taken along the line A-A' in FIG. Half-sectional view, Figure 2 (b) is B in (a)
-B' arrow view. 8... Bracket B, 9... Stator core, 10... Concave shaped groove. Name of agent: Patent attorney Shigetaka Awano and one other person Figure 8--7-RA 19 B

Claims (1)

[Claims] A brushless blower motor in which a plurality of recess-shaped grooves forming ventilation passages between the outer periphery of the stator core and the inner periphery of the bracket that holds the outer periphery of the circular stator core are formed.