JPS59165948A - Dc motor - Google Patents

Abstract

PURPOSE:To obtain high torque by arranging thin nonmagnetic material between adjacent field poles and increasing the area of the field poles. CONSTITUTION:A plurality of permanent magnets 1c are fixed to a yoke 10b. This magnets 1c are formed in sector shape, are arranged so that the adjacent polarities are opposite to each other on the surface of the yoke 10b, and a thin nonmagnetic material 11 is inserted between the poles. In this manner, the area of the poles can be increased, and effective crossing magnetic fluxes which cross the winding 8b of a motor armature by the magnetic flux of the magnets 1c can be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to the construction of a DC motor using permanent magnets as field poles.

Conventional Structure and Problems Conventionally, in a DC motor that uses a permanent magnet as a field pole, a circular permanent magnet 1 is used as the field pole as shown in FIG. It was fixed to the yoke 1a. Therefore, the area of the field poles is small, and the effective magnetic flux linkage with the armature winding 1b is small, making it impossible to obtain a large torque considering the dimensions of the motor.

OBJECTS OF THE INVENTION In view of the above-mentioned drawbacks, the present invention provides a high-torque DC motor by improving the armature interlinkage effective magnetic flux of the motor.

Structure of the Invention The present invention makes it possible to increase the field pole area by making each magnetic pole shape fan-shaped on the field pole surface of a DC motor and arranging a thin non-magnetic object between adjacent different magnetic poles. This has the effect of increasing the effective magnetic flux linkage with the child winding and obtaining high torque.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the structure of a DC motor including an embodiment of the present invention, and FIG. 3 shows a side view of a field pole in this embodiment. In FIGS. 1 and 3, an armature 6 and a commutator 7 are fixed on a rotating shaft 5 rotatably supported by bearings 3 and 4 attached to both ends of a housing 2, forming the rotating part of the motor. ing. The electric wire 6 is formed by arranging a predetermined number of flat armature windings 8b having a width approximately equal to the magnetic pole pitch on the circumference at an appropriate pitch, and molding them into a disc shape from resin. On the other hand, a yoke 10 to which a yoke 9 and a plurality of permanent magnets 1C are fixed with a slight gap in the axial direction facing the armature @ wire 8b portion of the armature 6 is fixed to the nousing 2, and the yoke 9 and the permanent Magnet IC, yoke 10 and armature cavity 12
A magnetic circuit is constructed. As shown in Fig. 3, the permanent magnet 1C (has a fan shape and is arranged on the surface of the yoke 1o so that adjacent magnetic poles are different from each other, and a thin non-magnetic object is placed between the adjacent magnetic poles. 11 has been inserted.

Furthermore, a predetermined number of brushes 15 are brought into contact with the outer periphery of the commutator 7, guided by a brush holder 13 fixed to the housing 2, and biased with an appropriate pressure by a compression coil spring 14 housed in the holder. ing.

The operation of the DC motor configured as described above will be explained below. When power is supplied from an external power source through the brush 15, the armature 6 placed in a magnetic circuit formed by the yokes 9, 1ob, permanent magnets 1C5, and the armature gap 12 rotates around the rotating shaft 5.

As described above, according to this embodiment, the permanent magnet 1C is made into a fan shape and the magnetic pole area can be increased by disposing a thin non-magnetic object between adjacent different magnetic poles.
A large amount of effective magnetic flux linkage can be obtained by the magnetic flux c interlinking with the armature winding 8b of the motor armature 6. Since the torque T of the DC motor is proportional to the product of the interlinkage effective magnetic flux Φ and the armature current I, it becomes TCy:ψI, and high torque can be obtained for the same motor size.

Effects of the Invention As described above, the present invention makes it possible to obtain a high-torque DC motor by disposing thin non-magnetic objects between adjacent field poles on the field pole surface of a DC motor and increasing the area of each field pole. It can be done, and its practical effects are great.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a DC motor according to an embodiment of the present invention, FIG. 2 is a side view of a conventional field pole, and FIG. 3 is a side view of a field pole according to an embodiment of the present invention. 1C... Permanent magnet, 6... Armature, 8b...
Armature winding, 11...Non-magnetic object. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 3

Claims (1)

[Claims] A DC motor in which a substantially fan-shaped permanent magnet is arranged on a field pole face facing an armature winding and fixed to a circular yoke, and a non-magnetic object is provided between different magnetic poles of the adjacent permanent magnets.