JPS60131052A - Magnet rotary motor - Google Patents

Abstract

PURPOSE:To reliably detect the pole of a magnet by providing a magnetic member between a winding and a sensor. CONSTITUTION:A megnet 3 is stably disposed to form a plurality of poles in the circumferential direction of a shaft to form a rotor, and an air gap is formed on the outer periphery to dispose a stator 4. A bracket 6 holds the stator 4 and a bearing 8, and a bracket 7 holds the stator 4, a bearing 8 and a sensor 9. The bearings 8, 8 support a shaft 1. A ring-shaped magnetic member 10a is projected integrally from a bracket 10 in the state that the winding 5 provided on the stator 4 and the sensor 9 are partitioned therebetween. The leakage magnetic flux from the winding 5 is passed through the member 10a.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a magnet-rotating electric motor that is incorporated into industrial and household equipment or equipment.

Structure of a conventional example and its problems FIG. 1 shows a conventionally used magnet rotating electric motor of this type.

In Fig. 1, 1 is a rotating shaft, and the 0 rotating shaft 1, the yoke 2, and the magnet 3 are generically referred to as the 0 rotating shaft 1, the yoke 2, and the magnet 3, which is arranged and fixed in a cylindrical shape through a yoke 2 so as to form multiple poles in the axial direction. o4, which is called a rotor, is a stator provided with a gap in the outer circumferential direction of the magnet 3, with a slot provided in the inner circumferential side, and a winding 6
is being wound around.

A bracket 6 is placed on one side, and the stator 4 is sandwiched between the bracket 7 and the bracket 7 placed on the other side. The bracket 6 holds the stator 4 and the bearing 8, and the bracket 7 holds the stator 4, the bearing 8, and the sensor/sensor 9, respectively, and the bearings 8, 8 receive the rotating shaft 1. The sensor 9 detects the magnetic pole of the magnet 3, and includes a control circuit (not shown) that generates a rotating magnetic field in the stator 4 in response to a signal from the sensor 9.

In the above configuration, an example in which a Hall IC is used as the sensor 9 and the magnet has two poles will be described below. As shown in FIG. 2, the sensor 9 detects the leakage magnetic flux of the magnet 3, and detects the position of the rotor by switching its magnetic pole. A current is then supplied to the armature through a control circuit that receives the signal from the sensor 9. If the position of the rotor in Fig. 2 A is the rotation angle O0, then B is 90o, C is 1800o, and D is 27o0. As shown in Figures 3 and 4, leakage magnetic flux is generated from the winding 6 as shown by the arrow, and the sensor/sensor 9 not only absorbs the leakage flux from the magnet 3 but also the leakage flux from the winding 6. However, if the leakage flux from the winding 6 is below a certain value Φ, it will not interfere with rotor position detection. However, when a certain constant value ψ can be handled, the point at which the magnetic pole detection of the sensor 9 normally switches (oQ in Fig. 2, 36○0290
0.1800,2700. ), the point shifted by θ0 (o0±θ0,900 vs. 00,1 in Figure 2)
8Oo±θo, 27○0±00), the magnetic pole switching is not transmitted to the control circuit, and as a result, the rotating magnetic field generated in the stator 4 and the rotor magnet field become smaller in electrical angle, and the electric motor This reduces the efficiency of

Unfortunately, the leakage flux from the winding 5 depends on the armature current, and as the armature current increases, the leakage flux from the winding 6 also increases. Therefore, when a load is applied to the motor and the armature current is increased, the leakage flux from the winding 6 increases and Φ
There was a problem in that it was impossible to increase the armature current and it was not possible to put much load on the motor.

OBJECTS OF THE INVENTION The present invention solves these conventional problems, ensures reliable detection by a sensor that detects the magnetic poles of magnets, and provides a magnet-rotating electric motor that is highly efficient even under high loads.

Composition of the Invention The magnet rotating electric motor of the present invention comprises a rotor in which magnets are arranged and fixed to form a plurality of poles in the circumferential direction of the shaft, a stator provided with an air gap on the outer circumferential side of the magnets, and the stator. a winding wire applied to the stake, a bracket provided to face the stake in the axial direction, and a sensor that detects the magnetic pole of the magnet;
A magnetic member is provided between the winding and the sensor to allow leakage magnetic flux from the winding to flow, so that the leakage magnetic flux from the winding does not affect the sensor.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 6 to 8. The same parts as those of the conventional example shown in FIGS. 1 to 4 are given the same reference numerals, detailed explanations are omitted, and only the differences will be explained. Reference numeral 10 denotes a bracket made of a magnetic material such as iron, which partitions the volume a5 and the sensor 9 into a bladder, and is integrated with a ring-shaped magnetic member 10 from 1-10.
A is formed protrudingly.

With the above configuration, the leakage magnetic flux from the winding 5 flows mυ through the magnetic member 10a, which has higher permeability than air, as shown by the arrows shown in FIGS. 6 and 7. Therefore, the leakage magnetic flux from the winding 5 , the sensor 9 does not pass through the detection surface of the sensor 9, which is located farther from the winding 5 than the magnetic member 10a of the bracket 1O.
does not affect rotor position detection. Also, magnet 3
The leakage magnetic flux flows at a constant magnetic flux density as in the conventional example, and the magnetic part 10a of the bracket 1○ located from the magnet 3 to the magnetic flux passing through the detection surface of the sensor 9 is located far from the detection surface of the sensor 9. has no effect. Therefore, the leakage magnetic flux of the magnet 3 used for detecting the rotor position can be equivalent to that of the conventional one.

Therefore, the point at which the magnetic pole of the magnet 3 detected by the sensor 9 switches is the rotation angle o 0 (3es oQ) in FIG.
.

9○o, 180027○0. The smell ensures that the rotating magnetic field generated in the stator 4 and the magnetic field of the rotor are always electrically stable, and the rotation of the rotor is stable.
This is a method that can significantly increase the efficiency of the motor under high loads.As shown in FIG. Although a ring-shaped ring is shown, it does not have to be ring-shaped. In short, any shape may be used as long as the leakage magnetic flux from the winding 5 passes through the magnetic member 10a and does not have any influence on the rotor position detection by the sensor 9. Further, in this embodiment, the magnetic member 10a is integrated with the bracket 1○, but it may be constructed as a separate part. Furthermore, if the material of the bracket 10 is a non-magnetic material, the magnetic member 10a made of a magnetic material is naturally separated. Must be provided as a component.

Effects of the Invention As is clear from the above embodiments, since the magnet rotating electric motor of the present invention has a magnetic member between the winding and the sensor, leakage magnetic flux from the winding does not affect the sensor. The position of the rotor can be detected reliably. Furthermore, the rotating magnetic field generated in the stator and the magnetic field of the rotor are electrically stabilized, and the rotor rotates smoothly, which is great for electric motors! 1゜ that can increase sex

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view showing an example of a conventional magnet-rotating electric motor, FIGS. The figure is a plan cross-sectional view and a side cross-sectional view showing leakage magnetic flux from the windings in the same magnet rotating electric motor. FIG. 6 is a longitudinal cross-sectional view of a magnet-rotating motor according to an embodiment of the present invention, and FIGS. 6 and 7 are plan and side cross-sectional views showing leakage magnetic flux from the windings in the magnet-rotating motor. , FIG. 8 is a cross-sectional perspective view of the bracket of the same magnet rotation type electric motor. 1...Rotating axis, 2...Yoke, 3...
...Magnet, 4...Stator, 6...Volume!
, 9... output sensor, 1○... placket),
10a... Protrusion of bracket. . Name of agent: Patent attorney Toshio Nakao
1 (8) Figure 2 (At 〆rhyme () (Ln 2) ρ' 4th l Figure 5

Claims (1)

[Claims] A rotor in which magnets are arranged and fixed to form multiple poles in the circumferential direction of the shaft, a stator provided with an air gap on the outer circumferential side of the magnets, a winding wire applied to the stator, and a winding in the axial direction of the stator. A magnet-rotating electric motor comprising: a bracket provided to face the magnet; a sensor that detects the magnetic pole of the magnet; and a magnetic member that causes leakage magnetic flux from the winding to flow between the winding and the sensor.