JPH0619294Y2 - Coil for brushless motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] In the present invention, the surface facing the rotor is wound so as to be a flat surface and arranged on the same circle to face the rotor on the flat surface.
The present invention relates to a coil used in a C brushless motor.

[Technical background of the device and its problems]

The conventional brushless three-phase motor for this type of DC is the fifth
It is formed as shown in FIGS. 6 and, which will be described below.

Reference numeral 1 denotes a rotor, and a magnet 2 having 8 poles is attached to the lower surface of the rotor.

The shaft 3 of the rotor 1 is supported by a bearing holder 4 attached to a top plate 5, and the lower end of the shaft 3 is placed on a thrust receiver 8 installed on a bottom plate 6 having an iron plate as a substrate. It can rotate smoothly.

The top plate 5 is attached to the bottom plate 6 by a post 7, and six coils 9 each having an approximately trapezoidal insulated wire are arranged and adhered on the same circumference with the thrust receiver 8 as a center. A hall element 10 is installed at the center of every other coil 9.

Then, the timing for energizing the coil 9 is controlled according to the output of the Hall element 10 to obtain the torque for rotating the rotor 1 in a fixed direction by the force generated between the coil 9 and the magnet 2.

In such a conventional DC brushless motor of the plane-opposing type, since the hall element 10 is installed in the coil 9 that drives the rotor 1, a space sufficient to accommodate the hall element 10 is provided in the central portion. This space is an obstacle to increasing the number of turns of the coil 9, and there is a drawback that the number of turns required to obtain a large starting torque cannot be obtained.

[Purpose of device]

The present invention is intended to eliminate the drawbacks of the coil of the conventional DC brushless motor of this type of plane-opposing type. In consideration of the recent decrease in the thickness of the hall element, the hall element is removed to eliminate the thickness of the hall element. An object of the present invention is to provide a coil for a brushless motor in which a coil is also wound in a central portion for accommodating an element and thereby a large starting force can be obtained.

[Example of device]

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

FIG. 1 shows a coil 11 according to the present invention, the center of which is slightly deeper than the thickness of the hall element 10 and the hall element 1
A space 11a larger than the outer shape of 0 is formed, and the space 11a
The surface opposite to a is an insulated wire wound so as to form a thin portion 11b so as to be a flat surface.

FIG. 2 shows a bobbin 12 for winding the coil 11.
The bobbin 12 is a side wall 12 forming an end surface of the coil 11.
a, a bulging portion 12b for forming the space 11a, and a cored bar 12c.

Therefore, if the insulated wire is wound by the bobbin 12 and the wound shape is maintained, the coil 11 of FIG. 1 is automatically completed.

As shown in FIG. 3, six coils 11 thus formed are arranged on the same circumference with the thrust bearing 8 as the center and bonded to the bottom plate 6 as in the conventional case.

At this time, as shown in FIG.
The surface 1a is bonded to face the bottom plate 6, and before the bonding, the hall elements 10 are accommodated and installed in every other coil 11.

The arrangement of the coils 11 in FIG. 3 is a three-phase 2 / 3π energizing motor, but it is also used for all other motors in which the Hall element 10 is installed in the coil 11 such as two-phase 2π energizing. Exert.

The Hall element 10 shown in FIG. 4 is of a chip type, but it goes without saying that the Hall element 10 with leads does not cause any problem.

Normally, the thickness of the coil 11 is 1.5 to 3 mm for a VTR or tape deck, and the recent Hall element 10 has a thickness of 0.6 or 0.8 mm. Therefore, the thin portion 11b
The thickness can be about 0.5 to 2 mm, so the number of turns can be considerably increased depending on the thickness of the insulated wire.

[Effect of device]

In consideration of the decreasing tendency of the thickness of the Hall element as described above, the present invention winds the winding to the center of the coil leaving a space of a thickness sufficient to accommodate the Hall element. Only the number of turns of the coil can be increased.

Therefore, the brushless motor using this coil can obtain a high starting torque at the time of starting without changing the shape and the material of the magnet, and can be more efficient at the steady state.

And since the Hall element is housed in the space of this coil, except for using a thin Hall element,
The effect is that the Hall element is not attached and other restrictions are not applied.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of the present invention, FIG. 2 is a side view of a bobbin winding the same, FIG. 3 is a plan view of a motor in which the bobbin is arranged, and FIG. FIG. 5 is a side view of a conventional brushless motor, and FIG. 6 is a plan view showing the arrangement of the coils. 6 ... bottom plate, 11 ... coil, 11a ... space, 11b
...... Thin part, 12 ...... bobbin.

Claims (1)

[Scope of utility model registration request] Claim: What is claimed is: 1. A coil formed by winding an insulated wire such that a surface facing a rotor is a flat surface, and a winding thickness of an inner peripheral portion of the coil is reduced to form a space accommodating portion of a hall element. Characteristic coil for brushless motor.