JPS5840767Y2 - motor stator - Google Patents

Description

[Detailed description of the invention] This invention relates to the stator of a motor used in a tape recorder, etc., and in particular, the bobbin with the stator winding wound thereon can be easily and easily inserted and removed from the bearing and housing. This invention relates to a stator structure for an outer rotor brushless motor.

Conventionally, the methods for attaching a motor drive coil wound around a bobbin to a bearing housing include simply injecting adhesive between them to fix them, simply press-fitting the bobbin into the bearing housing, or attaching the bobbin to the bearing housing. A method is known in which the housing is fixed to the end face of the housing using screws.

However, with any of these conventional methods, the position in the thrust direction becomes unstable due to the accumulation of tolerances between parts, and in particular, with adhesive fixing methods, the time and effort of temporary fixing to perform the bonding is significant. This is troublesome and requires a jig for one man for temporary fixing.

After the adhesive is injected, the bobbin and bearing housing must be housed in a curing device and cured for a fixed curing time.

However, this adhesive method has the disadvantage that both the bobbin and the bearing housing cannot be removed to easily maintain or inspect the coil portion or circuit connection portion.

On the other hand, with the press-fit fixing method described above, special attention must be paid to the dimensional control and quality control of each press-fit part, and after press-fit, it is impossible to remove both parts, and maintenance and inspection as described above are required. There were drawbacks such as it was not easy.

Further, as a method of attaching a ball using a screw, there is a method as shown in FIG. 1, for example.

In the figure, 9 is a bobbin that supports a wound stator coil 2, and a control circuit board 3 that controls the motor drive current supplied to the stator coil 2, and this control circuit board 3.
The fixed parts A and 1 have a bearing housing 4 for supporting the bearing housing 4 and a bracket 5 is attached to the bearing housing 4.
, a rotating part B equipped with a magnet 7 made of celadon so that a predetermined number of magnetic poles are provided on the inner circumferential surface of a magnet case 6, supporting this rotating part B so as to be rotatable about a shaft 8, and maintaining the above-mentioned bracket. It consists of a motor case (not shown).

These are integrally coupled, and when driving current is passed through the stator coil 2 one after another through the control circuit,
In the magnetic field formed by this drive current, the rotating part B having the magnet 7 is urged to rotate with respect to the fixed part A, and drives, for example, a capstan of a tape recorder through the shaft 8.

However, in this mounting method using screws, the mounting screw a
, b have to be used, resulting in poor workability.Furthermore, after a certain amount of time has elapsed, the screws become loose due to motor rotation, causing vibrations and causing many accidents such as screws becoming damaged. .

In this way, according to the conventional technique, the bobbin of the fixed part A is attached to the bearing housing 4 as follows.
Since this is unstable and troublesome, a fitting structure as shown in FIG. 2 has been proposed.

In FIG. 2, the bracket 5 is attached to the bearing housing 4 by caulking as shown in the figure. A shaped notch 10 is formed.

This hook-shaped notch 10 consists of a surface 11 perpendicular to the curved surface, a parallel surface 12 continuous to this, and an inclined surface 13 continuous to this parallel surface.

Further, bearings 15 and 16 for supporting the shaft 8 of the rotating portion B are press-fitted into both ends of the through hole 14 of the bearing housing 4, and the bearings 15 and 16 are made of oil-impregnated metal or
Bearings are used.

On the other hand, 17 is a bobbin that is added to the outer periphery of the bearing housing 4, and a cylindrical body 18 and a flange piece 19 raised thereon are formed of a relatively hard material such as Bakelite or synthetic resin as necessary. has been done.

A hook-shaped projection 20 is formed at one end of the cylindrical body 18 and is slightly smaller than the inner diameter of the through-hole and protrudes in sections. A vertical surface 22 following the end surface 21 and an inclined surface 23 continuing therefrom are provided.

On the other hand, an annular yoke 1 made of a ferromagnetic material is fitted into the collar piece 19, and a coil 2 is wound around the bobbin 17 so as to cover the yoke 1.

24 is an annular notch formed on the inner circumferential surface of the other end of the cylindrical body 18 of the bobbin 17;
The control circuit board 3 is held between the end face of the bobbin 17 and the flange piece 27 of the holder 26 into which the holder 26 is press-fitted.

Further, in FIG. 2, 29 is a coil spring interposed between the jaw 4a of the bearing housing 4 and the flange piece 27 of the holder 26 (7). In contrast, the horizontal end surface 21 of the hook-shaped projection 20 is strongly pressed against the bobbin 17, thereby absorbing the mounting play of the bobbin 17 with respect to the bearing housing 4 and positioning it.

The surface 11 and the horizontal end surface 21 constitute a mounting reference surface for these two parts.

Here, the bobbin 17 is connected to the bearing housing 4.
To install it, proceed as follows.

First, the coil spring 29 is fitted into the bearing housing 4, and the bobbin 17 is inserted into the bearing housing 4 from the holder 26 side.

In this case, the relationship between the hook-shaped notch 10 and the hook-shaped protrusion 20 is as shown in FIG. As shown in FIG. 4, the inclined surface 23 of the bearing housing 20 is widened at the edge of the bearing nozzle 4.

Furthermore, by continuing the pushing, the hook-shaped projection 20 falls into the hook-shaped notch 10 due to its restoring force, and by releasing the pushing,
Under the elastic force of the coil spring 29, the horizontal end surface 21 comes to be pressed against the surface 11 as shown in FIG.

Therefore, the position of the bobbin 17 in the thrust direction with respect to the bearing housing 4 is stably maintained, and its fixing can be performed simply and quickly without using conventional parts such as adhesives and screws.

Although the above-described fixing method is effective in the direction of removing the bobbin from the bearing housing, it is weak in the direction of pushing the bobbin into the bearing housing, so a coil spring 29 must be used to reinforce this.

Therefore, the present invention proposes a new fixing structure that is completely effective in both the pulling direction and the pushing direction with respect to the bearing housing using only the bobbin. I will explain further.

FIG. 6 shows a specific example of a bobbin used in the present invention,
FIG. 7 shows the mounting portion of the bobbin to the bearing housing, which is the main part of an embodiment of the present invention.

In FIG. 6, the bobbin 30 is integrally molded from polybutylene terephthalate, for example, and has three oval-shaped cross sections at its lower end (or upper end) and is latched at the tip. Fixing pawl portion 31,32 having a portion
, 33 and positioning pins 34 are formed.

When attaching the bobbin 30 to the bearing housing 35 made of aluminum, for example, as shown in FIGS. 7 and 8,
After attaching the bobbin 30 to the bearing housing 35, position the bobbin 30 so that the positioning pin 34 fits into the hole 36 provided on the lower end surface of the bearing housing 35, and then push the bobbin 30 into the fixing pawl 31, 32 and 33 engage with the inner convex stepped portion 37 of the lower end @ (or upper end 1) of the bearing housing 35 due to their elasticity and are automatically locked.

Furthermore, a ball bearing 38 is disposed within the bearing housing 35.
A predetermined motor stator is assembled in the manner described above, such as mounting and mounting the rotary shaft 39 and holding the rotating shaft 39.

As explained above, according to the present invention, the bobbin can be easily attached to the bearing housing and self-locked by using the unique mounting structure that utilizes the elasticity of the bobbin without using adhesives, screws, etc. The methods shown in FIGS. 2 to 5 have all the characteristics, of course, but also have a complete effect on the bobbin removal direction and pushing direction, and the same direction rotation. It can also be completely fixed.

Furthermore, it is easy to add and remove bobbins, the number of parts can be reduced, and there is no need to cut a tap in the bearing housing, resulting in a considerable cost reduction, which has extremely great practical effects.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing a conventional motor stator in which a bobbin is attached to a bearing housing with screws, Figs. FIG. 7 is a perspective view showing an example of a specific structure of a bobbin used in the invention, FIG. 7 is a schematic diagram showing the main part of an embodiment of the invention, and FIG. 8 is a view of the lower end thereof. 30: Bobbin, 31.32, 33: Fixing pawl, 34:
Positioning pin, 35: Bearing...Using, 38: Ball bearing, 39 One rotation axis.

Claims (1)

[Scope of utility model registration request] A cylindrical bearing housing having a convex stepped portion on the inside of the upper end or the lower end, a fixing pawl portion whose cross section is formed in an abbreviated shape at the upper end or the lower end, and a locking portion at the tip, and a positioning pawl portion. a synthetic resin bobbin having a pin, the bobbin is mounted on the bearing housing, the positioning pin is fitted into the hole in the end face of the bearing housing, and the fixing claw is inserted inside the end of the bearing housing. A motor stator characterized in that a bobbin and a bearing housing are integrated by engaging with a convex step.