JPH06197505A - Motor - Google Patents

Abstract

PURPOSE:To prevent operation failure of a motor even when unexpected fault such as breaking of wire and short-circuit is generated. CONSTITUTION:In a motor comprising a rotor having a core to which a plurality of coils 15 are wound, a stator composed of a plurality of permanent magnets 11 and a power supplying means consisting of power supply and commutators 21, 22 for bringing the conductive brushes 21, 22 making a continuity with power source and an electric coil 16 in a continuity, the power supply means are respectively provided in the vicinity of both ends of cores and are conductive to desired number of electric coils.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric motor used in a four-wheel steering system for an automobile, and more particularly to securing a motor output in the event of a failure such as disconnection or short circuit.

[0002]

2. Description of the Related Art As a conventional electric motor, Japanese Patent Laid-Open No. 3-12
There is one disclosed in Japanese Patent No. 4243. FIG. 2 shows a sectional view of an electric motor according to this technique. In the figure, a permanent magnet 31 is fixed to the housing 30, and a shaft 34 is supported via bearings 32 and 33. A fixed iron core 35 is fixed to the shaft 34, and a coil 36 is wound around the fixed iron core 35. Coil 36
The commutator 37 fixed to the shaft 34 is electrically connected to the commutator 37, and the commutator 37 constantly slides on the brush 38.
Since the brush 38 is electrically connected to a power source (not shown), the power source and the coil 36 are electrically connected via the brush 38 and the commutator 37. Further, the brush 38 and the commutator 37 form a power supply means.

[0003]

Since the above-mentioned conventional electric motor has only one electric power supply means, it becomes inoperable when the electric power cannot be supplied to the coil due to a disconnection or a short circuit and the output is not produced. It will be zero.

An object of the present invention is to prevent the electric motor from becoming inoperable even when an unexpected trouble such as disconnection or short circuit occurs.

[0005]

[Constitution of the invention]

[0006]

The technical means taken in the present invention for solving the above-mentioned technical problems are composed of a rotor having a core around which a plurality of electric coils are wound, and a plurality of permanent magnets. In a motor provided with a stator configured, a power supply unit configured with a brush that is electrically connected to a power source, and a commutator that is electrically connected to an electric coil, each of the power supply units has both ends of a core. That is, an arbitrary number of electric coils are electrically connected to the power supply means.

[0007]

The function of the present invention will be described. Since the power supply means are respectively provided in the vicinity of both ends of the core and an arbitrary number of electric coils are electrically connected to the power supply means, one power supply means is electrically connected to a part of the electric coils. In addition, even when a failure such as a disconnection or a short circuit occurs in one of the power supply means or the electric coil, the other power supply means is normal, so that it is possible to secure some output performance, and the electric motor cannot operate. There is no fall.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing an electric motor of this embodiment. In the figure, the housing 10 has a permanent magnet 11
Is fixed and supports the shaft 14 through bearings 12 and 13. A fixed iron core 15 is press-fitted and fixed to the shaft 14. A plurality of coils 16 are wound around the fixed iron core 15. The first commutator 17 is provided in half of the number of the coils 16 and the second commutator 18 is provided in the other half of the coils 16 and 20. And the respective commutators 17, 18 are electrically connected through the fixed core 1
Like No. 5, it is press-fitted and fixed to the shaft 14. In addition, the first and second commutators 17, 18 include the first and second brushes 21,
22 is always sliding. Each brush 21, 22
Are the first and second circuit boards 2 fixed to the housing 10.
3, 24 electrically connected to each other, and the first and second circuit boards 2
Reference numerals 3 and 24 are electrically connected to lead wires 25 and 26 from a power source (not shown). The commutators 17, 18 and the brush 2
1, 22 form a power supply means.

In the present embodiment, as shown in the figure, two commutators and two brushes are provided, respectively, and two power supply means are provided. Even if the wire breaks and disconnects and half of the coils are no longer supplied with power, the other power supply means is normal and current flows through the half of the coils, so the output is half, but does not stop.

When used in a four-wheel steering system of an automobile, power is secured to return the steering angle of the wheels to the neutral position when the electric motor becomes inoperable with the steering angle applied to the wheels. It is possible and leads to the improvement of safety.

[0012]

The effects of the present invention will be described. It is composed of a rotor having a core around which a plurality of electric coils are wound, a stator composed of a plurality of permanent magnets, a brush electrically connected to a power source, and a commutator electrically electrically connected to the electric coils. An electric motor having electric power supply means, the electric power supply means being provided in the vicinity of both ends of the core, and an arbitrary number of electric coils being electrically connected to the electric power supply means. Since the two power supply means are electrically connected to the different electric coils, even when a failure such as a disconnection or a short circuit occurs in one of the power supply means, the other power supply means is normal and the power output to a certain extent. Since it has the performance, the output performance does not become zero due to the inoperability of the electric motor.

On the other hand, since the commutator is located at both ends of the core, the commutator can be manufactured by the same method as the conventional manufacturing method, and it is not necessary to manufacture the commutator by a new method, which is low cost. .

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an electric motor according to the present invention.

FIG. 2 is a sectional view of a conventional electric motor.

[Explanation of symbols]

 10 ... Housing 11 ... Permanent magnet 14 ... Shaft 15 ... Fixed iron core 16 ... Coil 17 ... First commutator 18 ... Second commutator 21 ... First brush 22 ... Second brush 23 ... First circuit board 24 ... Second circuit board

Claims (1)

[Claims] 1. A rotor having a core around which a plurality of electric coils are wound, a stator composed of a plurality of permanent magnets, a brush that is electrically connected to a power source, and the electric coils are electrically connected to each other. In an electric motor comprising a power supply unit composed of a commutator, the power supply unit has each in the vicinity of both ends of the core, and the power supply unit is electrically connected to an arbitrary number of the electric coils. An electric motor characterized by being installed.