JPS59162667A - Magnetic encoder device - Google Patents

Abstract

PURPOSE:To detect magnetism with high precision by bringing one end of an information magnet into contact with the horizontal part of a stepped part formed on a rotary body and bringing an annular reinforcing material into contact with the other end face facing one end face and making an air bubble and a cavity part to disappear in an adhesive between a rotor yoke and the information magnet. CONSTITUTION:The lower end part of the rotor yoke 7 is bent in to a shape of a visor to form a stepped part 7a. An adhesive 12 is formed in a mass in the corner part of this stepped part 7a throughout the circumference. An annular information magnet 9 is mounted to the rotor yoke 7. An adhesive 12' is formed along a gap 13 throughout the circumference. Then, the gap 13 is enclosed with the adhesive to form a ring-shaped cavity 13'. The annular reinforcing material 13 is pressed from above the information magnet 9. The adhesive 12' is crushed by the pressure at this time to discharge air of the cavity 13' to the external, and upper and lower end faces and the inside circumferential face of the information magnet are covered with the layer of the adhesive having no cavity parts and are supported stably.

Description

[Detailed description of the invention] The present invention relates to a magnetic encoder device.

Figure 1 shows a cross section of a motor equipped with a magnetic encoder By. In the diagram, is code 1 a case? The printed circuit board 2 is superimposed on this, and the bearing holder 3 is fixed. Further, a stator core 4 and a stator core 5 are foamed to the bearing boulder 3 to form a stator thin member.

On the other hand, a rotary shaft 6 is attached to the bearing holder 3 through the shafts 9j, 0, and is integrated with the rotor *II6 (a rotor yoke 7 having a dish-like shape is provided to form a narrow rotor). A rotor magnet 8 is attached to the inner wall surface of the rotor yoke 7 facing the stator core 40, and the outer circumferential surface of the rotor magnet 8 has a number of N bridges and S bridges intersecting on the outer circumference. An array or ring-shaped information magnet 9 is provided.

A magnetic detector 11 is fixedly arranged in close proximity to the information magnet 9, and signals tX and I are output to control the speed of the motor. The main part of the magnetic type 1/coder equipment is composed of the news magnet 9 and the magnetic detector 11.

Conventionally, as a means of attaching the magnet 9 to the rotating body and the rotor yoke 7 at L° C., the magnets 9 have been attached by adhesion as shown in Fig. A'1, or by insert molding, but each method has its own problems.

For example, when using the I/Sartmold method, the cost is high and the Sei YI11 magnet may break in low vortices.

Also, in the adhesive hole '1', there was a void 91 in the filler between the No. 1 jiip magnet and the rotor yoke, making it difficult to tell if the adhesion was good. υ11、In the high temperature or high humidity T surrounding atmosphere, the hollow part where the hollow part is mixed expands and loses its roundness. If the circularity is not good, the gap with the magnetic detector becomes non-uniform, making it impossible to detect a single degree.

SUMMARY OF THE INVENTION An object of the present invention is to provide a magnetic encoder device that can solve the above-mentioned problems in the bonding method.

The i\If configuration of the present invention will be explained below based on an actual example.

Referring to FIG. 11d, the lower end of the rotor yoke 7 is bent into a canopy shape to form a stepped portion 7a.

First, glue the entire corner of this step 7a.
! I1. l r 2 is formed into a lump.

Next, as shown in Figure 3, a square-shaped news magnet 9 is attached to the rotor yoke 7. 1-, the lump-like adhesive 12 is pushed out, interposed between the stepped part and the lower end surface of the information magnet, and becomes in contact with the outer circumferential surface of the rotor yoke 7. There seems to be some intervention. However, as it is, the information magnet 9 will tilt due to the influence of heat because the gap 13 will be formed in the non-lead layer all around the circumference. Causes child problems.

Therefore, in the present invention, the upper t
3. Form an adhesive 12' along the gap 13 and over the tape 1. Then, the gap 13 is sealed with the adhesive to form a ring-shaped cavity 13'.

Next, as shown in Figure A-5,
information magnets 9 and 10. Then, due to the pressure at that time, the connecting material 12' is crushed and the upper part t1
The air in the cavity 13' is discharged to the outside, and the upper and lower surfaces of the Cheongju magnet and the inner IF 1 surface are supported stably by the adhesive layer having no cavity.

In this way, according to the present invention, the reinforcement is made indigenous to the rotor yoke and cleaned. Air bubbles and cavities formed in the adhesive between the LII magnets disappear, and the magnets can be bonded evenly all around. In addition, the adhesive surface is also different than before, so there is an advantage that even when it changes over time, the adhesive surface will be more stable.Furthermore, the S/G-shaped reinforcing pad makes the rotor yoke 7011' more flexible. However, if the W/F characteristics of the motor are good, the effect will be obtained.

[Brief explanation of drawings]

'/1.11 Figure 1 is a cross-sectional view of a motor using the magnetic encoder device according to the present invention. FIG. 7...Rotor yoke, 7 cuts...crotch, 12.12'...
・Adhesive, 13... Reinforcement/g.

Claims (1)

[Claims] In a magnetic encoder comprising a ring-shaped transition magnet provided on the circumferential surface of a rotating body and a magnetic detector disposed close to the magnet, the horizontal surface portion of the stepped portion formed by the rotating body y is provided. One end surface of the upper P information magnet is brought into contact with the
A ring-shaped reinforcing material is brought into contact with one end and the other end, and an adhesive is interposed between the inner circumferential surface of the information magnet and the outer circumferential surface of the rotating body and on the measuring abutment surface of the information magnet. A magnetic enocoder device that calculates %.