JPS6115555A - Magnet rotary type fan motor - Google Patents

Abstract

PURPOSE:To prevent a stator winding from being affected by the leakage magnetic flux by mounting a Hall IC for detecting the rotation between a bracket and a casing of a stator, thereby eliminating the temperature rise of the IC. CONSTITUTION:A Hall IC7 is provided between a bracket 11 secured to a stator 1 and a magnet 13. A fan 12 is secured to a shaft 3a rotated by a magnet secured to a rotor 3. Even if the rotor 3 is rotated and stator winding 2, the stator 1 and the rotor 3 are heated, air intaken from the hole 14a of a casing 14 is flowed by the fan 12 as by an arrow. Accordingly, the Hall IC is not affected by the heat. The leakage magnetic flux from the winding 2 is shielded by the bracket 11. The IC7 detects the rotating speed of the magnet 13 to become the prescribed speed.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a magnet rotation type fan motor used in so-called industrial and household applications.

Conventional configurations and their problems In recent years, this type of magnet-rotating fan motor has come to be used not only for low input and low output, but also for a wide range of applications. Hereinafter, a conventional magnet rotation type fan motor will be described with reference to the drawings.

In FIG. 1, 1 is a stator around which a winding 2 is wound, 3 is a rotor provided with a gap in the outer circumferential direction of the stator 1, and 4 is a rotor provided with a plurality of poles in the 1111 circumferential direction of the stator 1. A magnet arranged and fixed on the inner circumferential side of the rotor 3, 5 a fan attached to the outer circumferential side of the rotor 3, 6 a bearing that receives the rotor 3, 7 rotates by detecting the magnetic poles of the rotor 3. A sensor 8 for detecting the position is a base supporting the stator 1.

In the above configuration, the rotational position of the rotor 3 is determined by detecting leakage magnetic flux emitted from the magnet 4 fixed to the rotor 3 (
(The ball IC will be explained below as an example), and the vertical axis shows the output voltage V.L (V).

As shown in (with magnetic flux density B (Gauss) plotted on the horizontal axis), the rotor 3 is rotated by controlling the current flowing through the winding 2 at a certain magnetic flux density point, for example, point P. However, the temperature of the motor body rises due to current switching, rotation of the rotor 3, etc., and the ambient temperature of the Hall IC 7 fixed between the base 8 and the magnet 5 also rises, causing the Hall IC itself to rise. The temperature also rises. Therefore, the magnetic flux density sensitivity of the Hall IC 7 deteriorates, the current control of the winding 2 at point P becomes uncertain, and the efficiency of the fan motor decreases.
This causes a vicious cycle in which the temperature of the motor body rises, and as a result, the temperature of the Hall IC 7 itself also rises, lowering the magnetic flux density sensitivity of the Hall IC 7, and making the current control of the winding 2 at point P even more uncertain. I end up repeating myself.

Furthermore, since leakage magnetic flux as shown by the arrow in FIG. 1 is coming out from the winding 2, the Hall IC 7 is also affected by the leakage magnetic flux from the winding 2. However, the leakage magnetic flux coming out of the winding 2 depends on the winding current. Therefore, the winding current cannot exceed a certain value.

Purpose of the Invention The present invention solves these conventional problems and provides a sensor for detecting the rotational position of the rotor (casing and platen).
By arranging and fixing it in the part enclosed by A, it suppresses the temperature rise of the sensor, eliminates the influence of leakage magnetic flux from the winding, and ensures that the current switching position of the winding is kept constant. As a result, a magnet rotation type fan motor with excellent fan motor characteristics is provided.

Composition of the Invention The magnet-rotating fan motor of the present invention includes a rotating shaft, a rotor having first magnets arranged and fixed in an annular shape so as to form a plurality of poles in the circumferential direction of the rotor via a yoke, and a stator provided with a gap in the stator, a winding inserted into a slot provided in the stator, brackets A and B attached to the stator facing each other in the axial direction, and a bracket A and a bracket B attached to the bracket A. a second magnet arranged and fixed in an annular shape so as to have multiple poles in the circumferential direction of the shaft;
A casing containing the fan, an air guide, and a second magnet, a sensor that detects the rotational position of the rotor, and a control circuit that switches the current flowing through the winding based on a signal sent from the sensor. and has
By arranging and fixing the sensor in the part enclosed by the casing and the bracket, the temperature rise of the sensor is suppressed, the influence of leakage magnetic flux from the winding is eliminated, and the position at which the winding current is switched is kept constant. As a result, a magnet-rotating type fan motor with excellent fan motor characteristics can be obtained.

DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of a magnet rotation type fan motor of the present invention will be described based on the accompanying drawings. In FIGS. 3 and 4, the positions of the rotor and stator are reversed from those of the conventional example, but the same parts are indicated by the same reference numerals.

In the figure, 1 is a stator, 2 is a winding of the stator, and 3 is a rotor in which first magnets 4 are arranged and fixed in an annular shape so as to form a plurality of poles in the circumferential direction of the shaft via a yoke. The stator 1 is provided with a gap in the outer circumferential direction of the rotor 3. Further, the winding 2 is wound in a slot provided in the stator 1. 9 and 10 are upper and lower brackets attached to the stator 1 facing each other in the axial direction; 11 is an air guide attached to the outer periphery of the bracket 9; 12 is a fan fixed to rotate together with the rotor 3; 13;
Similar to the fan 12, g) a second electrode arranged and fixed in an annular shape with a plurality of poles in the axial circumferential direction between the air guide 11 and the fan 12 so as to rotate together with the rotor 3;
magnet, 14, is the air guide 11. A casing that encloses a fan 12 and a second magnet 13 and is attached to the stator 1. A sensor for detecting the rotational position of the rotor 3 is disposed in a portion enclosed by the casing 14 and the bracket I-9. ing. 15 is a control circuit that switches the current flowing through the winding 2 according to a signal sent from the sensor 7; 16 is a bearing that receives the rotating shaft 3a of the rotor 3 and is press-fitted into the brackets 9 and 10; 1) Sufan 12 of IJ, second magnet 13
and is a nut fixed to rotate together with the rotor 3.

In the above configuration, the sensor 7 (hereinafter explained using a Hall IC as an example) fixedly arranged between the air guide 11 and the second magnet 13 is connected to the second magnet 13 that rotates together with the rotor 3. The rotational position of the rotor 3 is detected by detecting the magnetic pole of the rotor 3. Then, the current flowing through the winding 2 is controlled at point P shown in FIG. 2, and the rotor 3 is rotated. As a result, the stator 12 winding 2, rotor 3, etc. generate heat, and the ambient temperature of the motor tends to rise. However,
Wind is generated in a fan 12 fixed to the rotor 3 so as to rotate together with the rotor 3 at r, -). The wind enters from the air suction port 142L provided in the casing 14 as shown by the arrow in FIG. Vent hole 10 & of bracket 10
go through. Therefore, the air heated by the heat generated by each part of the motor is blown out of the motor from the bracket 1o side along with the wind, and the temperature of the part enclosed by the bracket 9 and the casing 14 is not affected by the temperature rise of the motor body. . Therefore, the air guide 11 and the second magnet 1
The rise in ambient temperature of the Hall IC 7 fixedly arranged between the Hall IC 7 and the Hall IC 7 is suppressed, and the rise in the temperature of the Hall IC 7 itself is also suppressed. Therefore, the current switching position of the winding 2 becomes constant and reliable.

′-! In addition, leakage magnetic flux from the winding 2 occurs as shown by the arrow in FIG. However, since the Hall IC 7 is arranged and fixed in a portion enclosed by the bracket 9 and the casing 14, it is not affected by the leakage magnetic flux coming out of the winding 2. Therefore, the rotational position of the rotor 3 can be detected reliably, resulting in a magnet-rotating fan motor with excellent fan motor characteristics.

As shown in FIG. 5, a recess 3a is provided on the side where the fan 12 is arranged and fixed in the axial direction of the rotor 3, and a protrusion 12& is provided on the fan 12 to correspond to the recess 3a of the rotor. In addition, positioning of the fan 12 with respect to the rotor 3 becomes easy and reliable, and as a result, detection of the rotational position of the rotor 3 by the second magnet 13 that rotates together with the fan 12 becomes easy and reliable. Note that a D-cut portion may be provided in place of the recessed portion 3a, and a D-cut portion corresponding to the rotor D-cut portion may be provided in place of the convex portion 12a of the fan.

In short, it is sufficient that the rotor 3 and fan 12 can be easily and reliably positioned.

Further, as shown in FIG. 6, the second magnet 13 of the fan 12
By providing at least one or more recesses 12b on the side of the second magnet 13 that is connected to the fan 12, and providing a convex portion 13& on the side of the second magnet 13 that is connected to the fan 12 so as to fit into the recess 12b of the fan. 12 and the second magnet 13 becomes easy and reliable, and as a result, the positioning of the second magnet 13 with respect to the first magnet 4 becomes very easy and accurate. The second magnet 13 having the convex portion 13a can be easily formed into a convex portion even if it is a ferrite magnet or a rubber magnet.

From the above, the detection of the rotational position of the rotor 3 by the Hall E C7 is accurate and highly reliable in the magnet rotating type fan. In addition, the positional relationship of the recessed part and the convex part may be reversed in both FIGS. 5 and 6.

Effects of the Invention As is clear from the above embodiments, the magnet-rotating fan motor of the present invention has a sensor for detecting the rotational position of the rotor, which is arranged and fixed in the part enclosed by the casing and the bracket. , suppresses the temperature rise of the sensor, eliminates the influence of leakage magnetic flux from the winding, and keeps the current switching point of the winding constant and reliable, resulting in a magnet rotating fan motor with excellent fan motor characteristics. .

[Brief explanation of drawings]

Fig. 1 is a vertical cross-sectional view showing an example of a conventional magnet rotating fan motor, and Fig. 2 shows the output voltage on the vertical axis. The output voltage-magnetic flux density characteristic diagram of the sensor with the horizontal axis as the magnetic flux density, FIGS. 3 and 4 are longitudinal cross-sectional views showing the first embodiment of the magnet rotation type fan motor of the present invention, and FIG. A fan showing a second embodiment of the present invention. A perspective view of the rotor, and FIG. 6 is a vertical sectional view of the second magnet and fan showing the embodiment of FIG. 3. 1...Stator, 2...Winding, 3...
...Rotor, 4...First magnet, 7...
Sensor - 19, 10゛゛... Placket, 12...
Fan, 13...Second magnet, 14...
·casing. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Magnetic flux name 5 ((rαLIs3) Figure 3/63kil Figure 4 Figure 6/2b

Claims (3)

[Claims] (1) A rotor with first magnets arranged and fixed so as to form multiple poles in the circumferential direction, a stator provided with a gap in the outer circumferential direction of the rotor, and a magnet inserted into a slot provided in the stator. A winding, a bracket attached to the stator facing each other in the axial direction, an air guide attached to the bracket, a fan fixed to rotate together with the rotor, and arranged to have multiple poles in the circumferential direction of the axis. a second magnet fixedly installed; a casing containing the fan, the air guide, and the second magnet; a sensor for detecting the rotational position of the rotor; and a signal sent from the sensor to detect the winding. What is claimed is: 1. A magnet-rotating fan motor, comprising: a control circuit for switching a current flowing through a line; and wherein the sensor is disposed and fixed in a portion enclosed by a casing and a bracket. (2) The magnet rotating type fan motor according to claim 1, wherein a recess is provided on either the rotor or the joint surface of the fan with the rotor, and a protrusion that fits into the recess is provided on the other side. (3) A magnet-rotating fan motor according to claim 1 or 2, wherein one of the fan and the second magnet is provided with a recess and the other is provided with a projection that fits into the recess. .