JPH01209943A - Brushless motor - Google Patents

Abstract

PURPOSE:To compactly construct a brushless motor by providing a containing space on the outer face of a base opposite to that for holding a stator core, and mounting a magnetic detector and a drive circuit in the space. CONSTITUTION:In a brushless motor, a circuit substrate 20 associated with a magnetic detector 23 and a drive circuit is mounted on the lower face of a base 12 opposite to a stator core 10. The coil 11 of the core 10 is connected through connecting pins 18 to the substrate 20. The detector 23 is disposed by inserting a holder 24 to the hole 26 of the base 12 to face the inner periphery of a permanent magnet 5. A rotor 1 is controlled to be rotatably driven by the output from the detector 23. Thus, a motor can be compactly constructed, and preferable availability is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field 1] The present invention relates to an improvement in the structure of a brushless motor, and particularly to an improvement in a magnetic detector and drive circuit mounting structure.

[Prior art] Fig. 3 shows a sectional view of two types of conventional brushless motors, and the conventional example shown in Fig.
5G No. 6, a rotating shaft 42 is provided at the center of a cylindrical rotor 41, and a permanent magnet 43 is arranged on the inner peripheral surface. It is rotatably supported via a bearing 47 in the inner is of the cylindrical portion 44&, and the coil 4 is mounted on the outer periphery of the base 44.
The stator core 46 wrapped with 5 is fitted. base 4
A disk-shaped and ring-shaped wiring board 48 is disposed in the gap between the flat part 446 of the rotor 4 and the stator core 46, and a hole is provided on the wiring board 48 for detecting the rotational position of the rotor. A magnetic detector 49 such as an element is implemented.

In other words, in this type of brushless motor, a wiring board is often used to install the magnetic detector.
In this conventional example, a wiring board 48 is provided between a base 44 and a stator core 46. However, in this case, since the space between the base 44 and the stator core 46 is small, only the magnetic detector 49 can be installed, and the power supply circuit necessary to drive the brushless motor,
A drive circuit such as an amplifier circuit cannot be attached externally to the motor, which poses a problem in that the space required to drive the motor becomes large. In addition, the wiring connecting the motor and drive circuit becomes complicated, and when using a brushless motor, the product configuration also becomes complicated.Furthermore, maintenance of the circuit block cannot be done without removing the entire main body. Therefore, there was also the problem that it was troublesome.

[Problem to be Solved by the Invention 1] The present invention has been provided in view of the above-mentioned points, and the drive circuit is mounted on a wiring board and the wiring board is placed inside. The purpose of the present invention is to provide a compact brushless motor for the purpose of eliminating the inconveniences when externally attached.

Means for Solving Problem 1 1 [Function] The present invention provides a storage space on the outer surface of the base opposite to the side that holds the stator core, and stores the above-mentioned magnetic detection in this space. The present invention is characterized in that an external drive circuit is not required by disposing a wiring board on which a drive circuit for controlling the rotation of the rotor using the output of the magnetic detector and the magnetic detector is disposed.

[Embodiment 1] Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1st
The figure shows a cross-sectional view, and Figure 2 shows an exploded perspective view.The feature of the present invention is that the wiring board containing the drive circuit is placed in the storage space provided at the bottom of the base, making it compact. The reason is that the brushless motor is easy to use. The rotor 1 is formed into a cylindrical shape with one side closed, and a rotating shaft 3 is compressed and coupled to the center of the rotor 1 by a bush 4. *Furthermore, on the inner peripheral surface of this row 21, permanent magnets 5 magnetized to N pole and S pole are alternately arranged in the circumferential direction. A stator core 10 formed by layering a plurality of flat iron cores is surrounded from above and below by insulating frames 8 and 9 formed of molded products.

As shown in FIG. 2, the stator core 10 extends radially from the center and has a magnetic pole portion 10m at its tip that faces the inner circumferential surface of the permanent magnet 5 of the rotor 1 with a small gap interposed therebetween. Insulation frame 8,
A stator core 10 is disposed within a groove 9a of the insulating frame 9, and the insulating frame 8 is placed over the stator core 10.

The base 12 made of an insulating material is composed of a disk-shaped flat part 12b and a cylindrical part 12a integrally projecting upward from the central part, and a stator core 1 is arranged vertically on the outer surface of the cylindrical part 12a.
A lip 13 for positioning 0 is formed. The insulating frames 8 and 9 have engaging recesses 8b corresponding to the ribs 13.
, 9b are formed, and a recess 10b is formed inside the stator core 10, into which the protrusions protruding to form the engagement recesses 8b, 9b are fitted. The stator core 10 surrounded by the insulating frames 8 and 9 is mounted on the circle vIi portion 12a of the base 12 by engaging the engagement recesses 8b and 9b with the lip 13, and the stator core 10 surrounded by the insulating frames 8 and 9 is mounted on the upper part of the cylinder 11112m. The spring ring 22 is fitted into the circumferential groove 17, and the stator core 1
0 will be locked and fixed to the base 12. Further, the coil 11 is wound around the stator core 10 from above the insulating frames 8 and 9. Further, ribs 14 are integrally formed radially from the lower part of the cylindrical part 12a of the base 12 to the upper surface of the flat part 12b, and the magnetic pole part 10a of the stator core 10 is arranged behind the ribs 14. A fixing piece 15 is integrally provided to protrude outward from the outer circumference of the flat part 12b of the base 12, and the fixing piece 1
5 has a mounting hole 16 drilled therein. Further, a cylindrical bearing 19 is press-fitted and fixed inside the cylindrical portion 12m of the base 12, and the rotating shaft 3 is rotatably supported by this bearing 19.

The coil 11 wound around the stator core 10 is connected to the terminal IJt@ by a connecting pin 18 provided on the insulating frame 9, and the connecting pin 18 is connected to the wiring board 20 through a hole 25 drilled in the base 12.
It will be followed by one more time. A storage space 6 in which a wiring board 20 is arranged is provided on the lower surface of the base 12 on the side opposite to the stator core 10, as shown in FIG.

A magnetic detector 23 for detecting the rotational position of the rotor 1 is mounted on the wiring board 20.
A drive circuit and a power supply circuit for controlling rotation of the rotor 1 using the output from the rotor 1 are also mounted on the wiring board 20 for alarm.

The magnetic detector 23 is fixed to the wiring board 20 by a holder 24, and by soldering the lower end of the connecting pin 18 to the wiring board 20, the coil 11 and the drive circuit of the wiring board 20 are connected. The wiring board 20 is placed in the storage space 6 through the fixing screws 211 and fixed to the base 12α.The magnetic detector 23 is also connected to the holding screw 24 and the base 12. The inner peripheral surface l of the permanent magnet 5 is inserted through the hole 26 and is arranged to face the inner peripheral surface l of the permanent magnet 5.

[Effects of the Invention 1] As described above, the present invention includes a rotor in which permanent magnets are provided on the inner circumferential surface with permanent magnets magnetized with N poles and S poles alternately spaced at equal intervals in the circumferential direction, and tips of a plurality of magnetic pole parts are formed. a stator core whose outer circumferential surface faces the inner circumferential surface of the permanent magnet through a small gap; In a brushless morph equipped with a base on which the stator core is scattered and a magnetic detector that detects the rotating position of the permanent magnet, the outside of the base on the opposite side of the base that holds the stator core is A storage space is provided on the side, and a wiring board mounted with the above-mentioned magnetic detector and a drive circuit that controls rotation of the rotor using the output of this magnetic detector is placed in this space, so it can be used for storing the base. By configuring the magnetic detector and drive circuit integrally on the wiring board placed in the space, there is no need to separately configure the circuit required to drive the motor, and wiring when configuring the product is easy. It is easy to do this, the motor can be made compact, and it has the effect of improving usability.In addition, the wiring board can be placed in the storage space on the outside of the base on the opposite side from the stator iron. This has the effect that maintenance of the circuit blocks can be easily performed without disassembling the main body.

[Brief explanation of the drawing]

t141 is a sectional view of the embodiment of the present invention, FIG. 2 is an exploded perspective view of the same, and FIG. 3 is a sectional view of the conventional example. 1 is a rotor, 3 is a rotating shaft, 5 is a permanent magnet, 6 is a storage space, 10 is a stator core, 12 is a base, 20 is a wiring board, and 23 is a magnetic detector. Agent Patent Attorney Ishi 1) Chief Figure 7 3

Claims (1)

[Claims] (1) A rotor in which permanent magnets with N and S poles alternately magnetized at equal intervals in the circumferential direction are provided on the inner circumferential surface, and the outer circumferential surface formed by the tips of the plurality of magnetic poles is the inner circumference of the permanent magnet. a stator core disposed to face the surface with a small gap in between; a base that rotatably supports the rotating shaft of the rotor at its inner periphery and has the stator core mounted at its outer periphery; In the above-mentioned brushless motor equipped with a magnetic detector that detects the rotational position of the permanent magnet, a storage space is provided on the outer surface of the base opposite to that holding the stator core, and a storage space is provided within this space. A brushless motor comprising a wiring board on which is mounted the magnetic detector and a drive circuit for controlling rotation of the rotor using the output of the magnetic detector.