JPS6223233Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mechanism for attaching a permanent magnet of a motor to a bracket, and particularly relates to an improvement in a fixing mechanism using an adhesive.

Before explaining a conventional example of a fixing mechanism using an adhesive, the overall structure of a motor will be explained based on FIG. 1.

The motor itself shown in FIG. 1 is well known, and therefore will only be briefly described here.

In the figure, 1 is the case, and the central raised part 1
A bearing 2 is fitted into the center of a. A rotor shaft 3 projects outward from the center of the bearing 2.
Reference numeral 4 denotes a terminal, which energizes the armature winding 6 inside the rotor 5. 7 is a permanent magnet fixed on a bracket (yoke plate) 8. 9 is an end bracket.

In the motor constructed along this line, the present invention attempts to improve the fixing mechanism between the bracket 8 and the permanent magnet 7.

FIGS. 2 and 3 show a fixing mechanism for the permanent magnet 7 and bracket 8 of a conventional device.

First, FIG. 2 is a perspective view of the appearance of the permanent magnet 7 and the bracket 8.

In the figure, 10 is a ring-shaped permanent magnet with flat surfaces on both sides. 11 is a thin disk-shaped bracket made of magnetic material, and a bearing 12 is provided in the center. Further, the three-direction protrusions 11a on the outer periphery are locking pieces for locking to the motor. A permanent magnet 10 is attached to the magnet contact surface 11b of such a bracket 11.
When fixing, apply adhesive 13 to the entire contact surface of both, as shown in the vertical cross-sectional view of the fixed state in Figure 2.
was applied.

However, in this method of applying the adhesive, since the adhesive 13 is interposed between the permanent magnet 10 and the magnet contact surface 11b, the permanent magnet 10 is lifted from the bracket 11 by the thickness of the adhesive 13. It's going to go up. Furthermore, the presence of the adhesive increases the magnetic resistance between the permanent magnet 10 and the bracket 11, resulting in a disadvantage that sufficient motor output cannot be obtained.

In this way, when the permanent magnet 10 is lifted up relative to the bracket 11 and the rotor 5 etc. are installed,
Uneven rotation due to uneven clearance between the rotor 5 and the permanent magnet 10, or the rotor 5 and the permanent magnet 10
There have been cases where problems have arisen in which the

Furthermore, as described in Japanese Patent Application Laid-Open No. 52-97108, in a rotating electric machine having a structure in which a permanent magnet having an arcuate planar shape is fixed to the inner surface of a split housing having a semicircular planar shape, the By forming a hole penetrating the split housing in the thickness direction and making the curvature of the outer diameter of the permanent magnet larger than the curvature of the inner diameter of the split housing, a substantially crescent-shaped shape is formed between the split housing and the permanent magnet. form a gap.
A structure in which a permanent magnet is fixed to the inner surface of the split housing by injecting adhesive into the gap through the hole is already known.

However, this rotating electric machine has the following problems. In other words, even if you try to inject adhesive from the hole into the gap, the gap is filled with air, so it is difficult to completely fill the gap with adhesive, and the amount of adhesive filled is insufficient. At the same time, since air remains between the injected adhesive and the permanent magnet, adhesion between the divided housing and the permanent magnet is insufficient.

Since the opening of the hole is open, the adhesive injected into the hole is always in contact with the outside air, and as a result, the adhesive strength decreases due to moisture absorption, making it impossible to obtain stable adhesive strength over a long period of time.

The structure is such that a crescent-shaped gap is formed between the split housing and the permanent magnet, so whether the gap is filled with adhesive or air remains,
The area where the divided housing and the permanent magnet immediately come into contact becomes narrower, resulting in an increase in magnetic resistance.

The present invention was devised in view of the above-mentioned drawbacks of the conventional example, and it is an object of the present invention to provide a motor bracket device that has a simple structure and can reliably fix a permanent magnet.

An embodiment of the present invention will be described below with reference to FIGS. 4 and 5.

In the figure, the same parts as in FIGS. 2 and 3 are given the same reference numerals.

FIG. 4 is an external perspective view similar to FIG. 2.

As shown in the figure, the magnet contact surface 11 of the bracket 11
In b, a ring-shaped recess (notch groove) 11c is formed at the contact point of the permanent magnet 10. An enlarged diameter groove 11d is formed at three equal parts of the circumference of this recessed portion 11c.
is formed. The adhesive 13 is applied to this recess 11c,
The expanded diameter groove 11d is filled with it. Expanding groove 1
1d is provided to prevent excess adhesive that cannot be filled into the recess 11c from overflowing between the permanent magnet 10 and the bracket 11, and is an adhesive in which the excess adhesive flows and is held. It serves as a reservoir.

FIG. 5 shows the permanent magnet 10 relative to the bracket 11.
FIG. 4 is a longitudinal cross-sectional view similar to FIG. 3 showing a fixed state of FIG.

As is clear from the figure, the adhesive 13 is applied to this recess 11.
c and fixes the permanent magnet 10 at this location, and does not fit between the surface of the permanent magnet 10 and the magnet contact surface 11b of the bracket 11, so the permanent magnet 10 and the bracket 11 are tightly connected. It makes contact and does not lift up.

Although the recessed portion 11c is formed in a ring shape in this embodiment, it is not limited to this, and in short, any continuous or discontinuous recessed portion may be formed at appropriate locations on the magnet contacting surface 11b of the bracket 11. All that is needed is to fill the recess with adhesive.

As described above, the present invention forms a bottomed recess and a bottomed adhesive reservoir that communicates with the recess and is wider than the recess on the magnet contact surface of the bracket that fixes the permanent magnet. This is characterized in that the permanent magnet and the bracket are bonded together using an adhesive injected into the recess. Therefore, when adhesive is injected into the recess, air remains between the bottom of the recess and the injected adhesive;
Since this air layer is on the opposite side to the bonding surface, there is no concern about adhesion failure due to the intervening air layer as proposed in the past, and high bonding strength can be obtained.

The injected adhesive is surrounded between the permanent magnet and the bracket after assembly, and is not in direct contact with the outside air as in conventional proposals.
There is no decrease in adhesive strength due to moisture absorption, and stable adhesive strength can be maintained for a long period of time.

Since the adhesive reservoir is wider than the recess, excess adhesive will not overflow between the permanent magnet and the bracket. Therefore, the adhesive layer is only provided at predetermined locations.
Since the permanent magnet and the bracket are in direct contact with each other in other parts, there is no increase in magnetic resistance due to the presence of adhesive, and sufficient motor output can be obtained.

Therefore, it is possible to provide a highly accurate motor bracket.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of the entire motor, Fig. 2 is an exploded external perspective view of a conventional device, Fig. 3 is a vertical sectional view of a conventional device, and Fig. 4 is an exploded external appearance of a device according to an embodiment of the present invention. The perspective view and FIG. 5 are longitudinal sectional views thereof. 10...Permanent magnet, 11...Bracket, 11
b... Magnet contact surface, 11c... Concave portion, 13... Adhesive.

Claims (1)

[Scope of utility model registration request] In a motor bracket in which a permanent magnet is fixed with an adhesive, a bottomed recess and a bottomed adhesive reservoir communicating with the recess and wider than the recess are formed on the magnet contacting surface of the bracket. A motor bracket device characterized in that the permanent magnet and the bracket are bonded to each other by an adhesive injected into the recess.