JPS6034355B2 - Manufacturing method of DC brushless motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a DC brushless motor in which brushes and commutators, which have reliability problems due to wear and tear, are replaced with semiconductors. The present invention relates to a method of fixing a marker used in combination with a light receiving/emitting element.

Examples of conventional DC brushless motors include those shown in FIGS. 1 and 2. In the figure, 1 is a rotor, which includes a rotating yoke 2 and an annular magnet 3 fixed to the rotating yoke 2.
It is fixed to the rotor shaft 5 via the sleeve 4.

Similarly, a marker 6 is attached to the rotor shaft 5 via a sleeve 4 so as to be spaced apart from the rotary yoke 2 in parallel. The marker 6 is formed by providing a light and dark pattern 6b on the opposite side of the rotating yoke 2 of a thin disc 6a, and the light and dark pattern 6b has a serration whose cross section in the direction perpendicular to the axis is the same.
It has an annular shape with concave and convex surfaces that look like they are stacked on top of each other. A fixed yoke 7 has a printed circuit board 8 superimposed on the fixed yoke 7, and a plurality of coils 9 are arranged and fixed in an annular manner on the upper surface of the fixed yoke.

A seat 10 is provided on the fixed yoke 7 at the center of these annularly arranged coils 9. Moreover, the rotor 1 is
It is rotatably attached to case 12 via rotor shaft 5 and bearing 11 .

Another printed circuit board 13 is attached to the case 12 so as to face the marker 6, and the printed circuit board 13 is further provided with a light receiving/emitting element that detects the rotational speed or position of the rotor 1 in pair with the light/dark pattern 6b of the marker 6. 14 and 15 are provided corresponding to the bright and dark pattern 6b. By fixing such a case 12 to the fixed yoke 7 side, the lower end of the rotor shaft 5 is supported by the seat 1, and the rotor 1 is rotatably mounted.

Note that 16 is a transistor or the like connected to the printed circuit boards 8 and 13. The marker 6 of the DC brushless motor having such a structure is manufactured by forming a light and dark pattern 6b on a disc 6a.
, or a film on which the light and dark pattern 6b was printed was attached using a rubber adhesive.

Therefore, in painting, the precision of the light and dark pattern is not sufficient and it takes a lot of man-hours, and in the case of normal adhesion using rubber adhesive, the smoothness of the marker surface is poor, and the reliability of the adhesive force is low. was there.

Therefore, this invention was developed in view of these problems, and uses a heat-sensitive adhesive film as a marker, and uses the heat generated and attraction force when magnetizing with a magnetizer to attach it to the rotor. The aim is to solve the Kamitakuma problem by doing so.

Next, this invention will be explained based on the drawings.

3 to 5 are diagrams showing an embodiment of the present invention.

In the drawings, parts or members that are the same or equivalent to the subordinate columns are designated by the same reference numerals and redundant explanations will be omitted. In the figure,
The marker is made of a non-magnetic heat-sensitive adhesive film 20a using, for example, a thermosetting adhesive, and has a light and dark pattern 20b on its surface, similar to that shown in FIG.

This marker 20 is attached to the surface of the magnet structure 23 of the rotor 21 on the fixed yoke 7 side. Receiving and emitting elements 14 and 15 for detecting the rotational speed and position of the rotor 21 are provided at the center hole position of the coil 9 which is annularly mounted on the fixed yoke 7 and the printed circuit board 8, corresponding to the light and dark pattern 20b of the marker 20. is being used. Therefore, in this invention, the marker 20 is attached to the magnet structure 23 between the magnet structure 23 and the coil 9, and the conventional marker 6 is provided on the opposite side of the rotary yoke 2 from the magnet 3. The difference is that

Furthermore, the printed circuit board 13 is no longer necessary and the size is smaller, but the other configurations are the same. An example of a method for manufacturing a DC brushless motor having such a configuration is performed as follows.

First, an annular magnet structure 23 is fixed to the rotary yoke 2 to form the rotor 21, and further fixed to the rotor shaft 5 via the sleeve 4.

Next, the marker 20 with the light and dark pattern 20b printed on the heat-sensitive adhesive film 20a by hot stamping or the like is applied to the magnet structure 23. This marker 201 is pressed against the magnetizer 30 to magnetize the magnet structure 23 into a desired magnetic pole arrangement, and the marker 20 is bonded to the marker 20 by heat and attraction during magnetization. In the magnetizer 30', magnetizing coils 32 are wound around protrusions 31a corresponding to the desired number of magnetic poles of the magnetizing yoke 31, with alternate winding directions. In such a magnetizer, when the magnetizing coil 32 is energized for magnetization, heat is generated in this part. Therefore, by aligning the position of the bright/dark pattern 20b with the position of the magnetizing coil 32 of the magnetizing device 30, pressurizing the marker 20, and energizing the magnetizer 30, the magnet structure 23 is magnetized with magnetic poles and turned into a magnet. The heat generated at this time softens the adhesive of the heat-sensitive adhesive film that is the material of the marker, and the marker 20 is attached to the magnet structure 23. Then, the attraction force generated at this time causes the marker 20 to be brought into close contact with the surface of the magnet structure 23, so that the marker 20 is firmly and flatly attached. On the other hand, a coil 9 is arranged in a ring shape around a catch 10 on a printed circuit board 8 superimposed on the fixed yoke 7, and light-receiving and emitting elements 14 and 15 are arranged in one center hole of the coil 9. Solder the necessary transistors, etc. 16.

The shaft 5 to which the rotor 21 is attached is mounted on the bearing 11, and the rotor 1 is mounted in the case 12 so that the marker 20 faces the light receiving/emitting elements 14 and 15 attached to the hole position of the coil 9.
Attach it so that it can rotate freely. The DC brushless motor manufactured in this way detects the rotational speed or position of the rotor 21 by detecting changes in brightness and darkness of the brightness and darkness pattern 20b of the marker 20, which serves as a reflector, using the light receiving and emitting elements 14 and 15, and detects the rotational speed or position of the rotor 21. By controlling the time each coil 9 is energized, it rotates without uneven rotation.

As explained above, according to the present invention, when the magnet component is magnetized by the magnetizer, at the same time, the generated heat softens the adhesive of the heat-sensitive adhesive film that is the material of the marker and attaches the marker. This shortens the manufacturing process and significantly improves production efficiency.

During energization and magnetization, a strong attractive force acts between the magnetization yoke and the magnet structure, so that the marker can be adhered reliably and flatly. If the magnetizer is preheated, the marker can be bonded more reliably.

[Brief explanation of the drawing]

Fig. 1 is a central sectional view of a conventional DC brushless motor, Fig. 2 is a plan view of a marker used in the motor shown in Fig. 1, and Fig. 3 is a central sectional view of a conventional DC brushless motor.
Figures 5 to 5 relate to this invention, with Figure 3 being an exploded explanatory view of pasting markers on the rotor, and Figure 4 being an exploded view of the main parts showing the assembly of the rotating yoke side and the fixed yoke side. The perspective view and FIG. 5 are central sectional views of the DC brushless motor. 2...Rotating yoke, 5...Rotor koji, 9.
... Coil, 14, 15 ... Light receiving and emitting device, 20 ... Marker, 20a ... Heat sensitive adhesive film, 20b ... Heart light and dark pattern, 21...
...Rotor, 23... Magnet machine assembly, 30...
. . . Magnetizer, 31 . . . Magnetizing yoke, 32.・
...Magnetizing coil. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] 1. In order to detect the rotational speed or position of the rotor, a heat-sensitive adhesive film is used for a marker provided corresponding to the light receiving/emitting element, the marker is brought into contact with a magnet structure fixed to the rotor, and then the desired By press-contacting a magnetizing yoke around which a magnetizing coil is wound in an arrangement to the magnet structure and energizing the magnetizing coil, the magnet structure is magnetized to a desired magnetic pole arrangement, and at the same time, the magnetization A method for manufacturing a DC brushless motor, characterized in that the thermosensitive adhesive film serving as the marker is bonded under heat and pressure by the heat generated and the suction force generated during the step, thereby adhering the marker to the magnetic structure.