JPH05115166A - Dc brushless motor - Google Patents

Abstract

PURPOSE:To realize a thin DC brushless motor by mounting an IC chip below an armature and resin sealing the IC chip. CONSTITUTION:A recess 12 is made below an armature 9 in a metal substrate 7A covering the opening at the bottom of a frame 2. After mounting an IC chip 10A in the recess 12, the IC chip 10A is molded of thermosetting resin 13 thus eliminating restriction in the thicknesswise direction due to the thickness of a coil 8 applied onto the armature 9 and obtaining a thin DC brushless motor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a DC brushless motor used in OA equipment or audio / video equipment.

[0002]

2. Description of the Related Art In recent years, OA equipment, audio equipment, and video equipment have tended to be smaller and thinner. As a result, DC brushless motors are required to be smaller and thinner.

The structure of a conventional DC brushless motor will be described below with reference to FIG.

As shown in the figure, the rotary shaft 1 includes a bearing 3 held by a frame 2 having an open bottom and a thrust receiving plate 4.
A rotor frame 6 having a cylindrical rotating permanent magnet 5 that is pivotally supported and is magnetized in multiple poles is mounted. In addition, the resin member 11 is provided on the substrate 7B that covers the opening at the bottom of the frame 2.
The armature 9 around which the coil 8 is wound, the bearing 3 and the thrust receiving plate 4 are mounted, and the IC 10B for driving or driving control is mounted on the surface facing the armature 9. A shield plate 13 for shielding magnetic noise is provided on the back surface of the substrate 7B.

[0005]

In such a conventional DC brushless motor, the IC 10B is arranged on the substrate 7B so that the IC 10B is located in the slot portion between the salient poles of the armature 9. Although the DC brushless motor has been made thinner, there is a problem that it is difficult to make the DC brushless motor thinner due to the thickness of the coil 8 wound around the armature 9.

The present invention solves the above problems, and an object thereof is to provide a thinner DC brushless motor.

[0007]

In order to achieve the above object, the present invention is directed to a frame having an open bottom portion, a rotor portion mounted on a rotating shaft and having a rotating permanent magnet magnetized in multiple poles, A bearing portion that rotatably supports the rotating shaft,
A stator section having an armature mounted on a metal circuit board covering the opening of the frame, and a driving or drive control IC chip are provided, and a concave section is formed below the armature of the metal circuit board. The IC chip is mounted on the concave portion and sealed with a thermosetting resin.

[0008]

As described above, according to the present invention, since the IC chip is mounted in the concave portion formed below the armature of the metal circuit board and sealed with the thermosetting resin, the coil wound around the armature is reduced. It is possible to eliminate the restriction in the thickness direction due to the thickness of the.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

The same parts as those shown in the conventional example are designated by the same reference numerals, and the description thereof will be omitted. As shown in the figure, a concave portion 12 is formed below the armature 9 on the metal circuit board 7A that covers the opening at the bottom of the frame 2.
The metal circuit board 7A is a metal plate whose surface is provided with a flexible electrical insulation coating, and the concave portion 12 is formed by machining. The recess 12 has an IC
The chip 10A is mounted, and after the mounting, the thermosetting resin 13 is dropped to seal the IC chip 10A.

As described above, according to the DC brushless motor of the embodiment of the present invention, the chipped IC chip 10A is mounted in the concave portion 12 formed in the metal circuit board 7A, and the thermosetting resin 13 seals and molds. As a result, the IC chip 10A is prevented from protruding onto the surface of the metal circuit board 7A, so that there is no restriction in the thickness direction due to the thickness of the coil 8 wound around the armature 9, and the DC brushless motor can be made thinner. There is an effect that can be done.

[0012]

As is apparent from the above description of the embodiments, according to the present invention, the IC chip is mounted in the concave portion formed below the armature of the metal circuit board and sealed with the thermosetting resin. Since the mold-stopping is performed, there is no restriction in the thickness direction due to the thickness of the coil wound around the armature, and a thin DC brushless motor can be provided.

[Brief description of drawings]

FIG. 1 is a side sectional view of a DC brushless motor according to an embodiment of the present invention.

FIG. 2 is a side sectional view of a conventional DC brushless motor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 rotating shaft 2 frame 3 bearing 5 cylindrical rotating permanent magnet 7A metal circuit board 9 armature 10A IC chip 13 thermosetting resin

Claims (1)

[Claims] 1. A frame having an open bottom, a rotor portion mounted on a rotating shaft and having a rotating permanent magnet magnetized in multiple poles, and a bearing portion rotatably supporting the rotating shaft.
A stator section having an armature mounted on a metal circuit board covering the opening of the frame, and a driving or drive control IC chip are provided, and a concave section is formed below the armature of the metal circuit board. A DC brushless motor in which the IC chip is mounted in the recess and sealed with a thermosetting resin.