JPS585420Y2 - Stator of permanent magnet DC machine - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a stator for a permanent magnet DC machine such as a DC motor or generator, and is particularly concerned with a magnetic pole fixing device that is effective for small-sized machines.

In high-performance permanent magnet DC machines used for servos, magnetic pole pieces are attached to permanent magnet field poles that are considerably large compared to the armature diameter. Conventionally, adhesives were bonded using thermosetting resins because various forces act on them, such as magnetic force, impact force at startup, and vibration/impact force during transportation.

This gluing process requires time and effort, such as adjusting the adhesive and temporarily mounting each part, requires equipment such as a heating furnace, and has the disadvantage of being time-consuming.

Furthermore, there was also a reliability problem due to variations in adhesive strength.

The present invention has been made to improve the above points, and an embodiment shown in the drawings will be described below.

Reference numeral 1 denotes a yoke, and 2 a permanent magnet field pole. An even number, for example four, are arranged on the inner circumferential surface of the yoke 1 surrounding an armature (not shown).

Reference numeral 3 denotes a magnetic pole piece, which is formed into a tapered shape with both sides inclined in order to concentrate the magnetic flux, and is arranged at the tip of each field pole 2 so as to face the armature through a narrow gap. .

4 is an elastic plate made by bending a thin plate such as non-magnetic stainless steel into a U-shape, and is inserted between adjacent magnetic pole pieces 30, the outer surface is in contact with the side surface of the magnetic pole piece 3, and the connecting side is formed with a narrow gap. It faces the armature through the yoke 1, and its open end is in contact with the inner surface of the yoke 1.

Therefore, at the point of contact between the outer surface of the elastic plate 4 and the inclined surface of the magnetic pole piece 3, the magnetic pole piece 3 is pressed in the direction perpendicular to the inclined surface, and due to the pressing force from one side of the magnetic pole, the magnetic pole piece 3 pushes against the field pole 2. It is pressed against the yoke 1 through the yoke.

Therefore, the field pole 2 and the pole piece 3 are held in place within the yoke 1 sufficiently strongly without the use of adhesive.

In addition, since the connecting side of the elastic plate 4 faces the armature through a narrow gap, and the opening side end contacts the yoke 1, the magnetic pole piece 4
The heat generated from the armature between the two parts can be efficiently absorbed and transferred directly to the yoke 1, or can be cooled by internal cooling air from the surface of the elastic plate, thereby greatly improving the cooling effect.

Various materials and shapes are conceivable for the spacing piece 4, but any material may be used as long as it has enough elasticity to press and hold the field pole and the magnetic pole piece against the yoke.

As described above, the stator of the permanent magnet DC machine according to the present invention has a U-shaped elastic force that contacts and presses the inclined surface of the magnetic pole piece between the tapered magnetic pole pieces provided at the tips of the permanent magnet field poles. Because the plate is inserted with the connecting side facing the armature, the field pole and magnetic pole piece can be fixed to the yoke without using adhesive, which significantly reduces assembly man-hours, and the magnetic pole and elastic plate can be fixed. By press-fitting the yoke from one side of the yoke, assembly can be automated, and the cooling effect can be improved by absorbing heat from the armature through the wide elastic plate.

[Brief explanation of drawings]

The figure is a cross-sectional view of an embodiment of the present invention. 1 is a yoke, 2 is a permanent magnet field pole, 3 is a magnetic pole piece, and 4 is an elastic plate.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. A yoke 1, an even number of permanent magnet field poles 2 arranged on the inner periphery of the yoke 1 so as to surround the armature, and at the tips of these permanent magnet field poles 2. Tapered magnetic pole pieces 3 are arranged to face the armature through a narrow gap, and the outer surface contacts the side surface of the magnetic pole piece 3 between the adjacent magnetic pole pieces 3, and the connecting side has a narrow gap. The opening side faces the armature through the yoke 1.
A stator for a permanent magnet DC machine, which includes a U-shaped elastic plate 4 inserted so as to come into contact with the inner surface of the permanent magnet DC machine. 2. A stator for a permanent magnet DC machine according to claim 1, in which the elastic plate 4 is made of a non-magnetic material.