JPS58195439A - Brushless motor - Google Patents

Abstract

PURPOSE:To enable to readily manufacture a brushless motor by winding a core of a wire material on the outer peripheral side of a cylindrical coil so as to increase the laminated layer amount at the axial center. CONSTITUTION:A core 2 of a stator made of a magnetic wire material is provided on the outer periphery of a cylindrical coil 1, and a rotor 3 formed of a permanent magnet is provided at the inside. The coil 1 and the core 2 are molded with a moldable and insulating material such as resin or the like to form a frame 4. Further, bearing brackets 5, 6 which support the rotor 3 are provided at both axial ends of the frame 4. In this structure, the core 2 of a brushless motor is formed by mounting the coil 1 on a cylindrical jig and winding the wire material from the outer peripheral side. In this case, the wire material is wound in less amount at both axial sides and wound in more amount at the central side.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a brushless motor structure that has good performance, is easy to manufacture, and is inexpensive.

Brushless motors using cylindrical coils are difficult to manufacture because of the structure of the stator core provided around the outer periphery of the cylindrical coils, and this affects not only the characteristics but also the manufacturing cost.

Furthermore, if the iron core is constructed from laminated steel plates, the volume will not correspond to the magnetic flux density, and if the core is constructed based on the portions with high magnetic flux density, the volume will be wasted in the portions with low magnetic flux density.

-1- For example, in an iron core made of laminated steel plates, it is difficult to converge the air gap magnetic flux at the end of the armature winding, so the magnetic flux at the end of the iron core decreases and the motor characteristics deteriorate.

Therefore, a brushless motor has to be constructed which has a large volume, is heavy, and has high material costs.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a brushless motor that can be easily and inexpensively manufactured and has good characteristics.

Hereinafter, the present invention will be explained based on an embodiment shown in the drawings. The figure is a vertical cross-sectional view and cross-sectional view of a main part of a brushless motor according to an embodiment of the present invention. A stator iron core 2 is provided, and a rotor 3 made of permanent magnets is provided inside.

The cylindrical coil 1 and the iron core 2 are molded with a material such as resin that is moldable and has good insulation properties to form a frame 4.

Further, a rotor 3-2 is provided at both axial ends of the frame 4.
- A bearing bracket 5.6 is provided which supports the.

Moreover, the air-magnetic flux generated between the rotor 3 and the iron core 2 is as indicated by the arrow in the figure.

In such a configuration, in the brushless motor, the cylindrical coil 1 is attached to a cylindrical jig, and the iron core 2 is formed by winding a wire rod from the outer circumferential side.

At this time, less wire is wound on both sides in the axial direction, and more wire is wound around the center.

Such a wire can be wound easily and accurately by rotating the jig.

Further, by rotating the jig and adjusting the axial feed at φ, a predetermined winding state can be easily obtained.

This winding of the wire rod is carried out with the cylindrical coil 1 interposed in the jig, so II! :! It is easy to properly tighten the structure so that it does not collapse.

Furthermore, when constructing the frame 4, if it is molded with resin or the like, a brushless motor with a uniform outer periphery can be formed without being affected by the unevenness of the outer periphery of the iron core 2 caused by wire rods.

Of course, a frame having a conventional structure such as a steel plate can also be used, and in this case, there is no problem even if a support is interposed between the iron core 2 and the frame.

Since the iron core 2 is made of wire, the iron core can be easily configured to correspond to the magnetic flux during operation.

That is, the number of winding devices is increased in areas where the magnetic flux density is high so that the volume of the iron core is increased.

Then, a wire is wound around a portion where the magnetic flux density is low, for example, at the end of the iron core, so that the volume of the iron core is reduced.

By configuring the iron core 2 in this manner, the number of heavy wire rods can be kept to the minimum necessary, and the core 2 can be configured to be small, lightweight, and inexpensive.

Further, the electrical properties are extremely convenient without deterioration.

Brushless motors configured in this way are small
Taking advantage of the lightweight L-shape, it is extremely effective as a drive source for industrial robots, etc.

-4- Also, in combination with the resin molded frame 4, it becomes an electrical drive source with good insulation.

In addition, the iron core 2 made of wire rods is advantageous because it does not cause eddy current loss in the same way as the iron core made of laminated steel plates, but it produces magnetic resistance because it causes wire gaps in the direction of magnetic flux flow (radial direction). In particular, the magnetic flux within the core tends to concentrate at the center in the axial direction, as indicated by the arrow in the figure.

However, such a tendency can be effectively countered because unlike the case of an iron core made of laminated steel plates, it is extremely easy to increase the number of winding devices in areas where the magnetic flux density is high.

The magnetic wire according to the present invention is applicable to all so-called ferromagnetic wires such as steel, iron alloys, and amorphous metals, and the cross-sectional shape of the wire can be circular, square, rectangular (including ribbon shape), etc. is common, but is not particularly limited to this.

As explained above, according to the present invention, since the iron core made of wire rod is wound around the outer circumferential side of the cylindrical coil so that the number of laminated layers is increased in the central part in the axial direction, efficiency is improved. A brushless motor with the above-mentioned advantages can be obtained, and its effects will be of great benefit to the industry.

[Brief explanation of the drawing]

The figure shows the main part 1 of the brushless motor according to the present invention [J 1l
It is a li side view. 1...Cylindrical shape = Iil, 2...Iron core, 3...[
1-ta, 4...frame. Patent N Applicant Shibaura Seisakusho Co., Ltd. -6- 6.5 Procedural Amendment 14ii (Method) % Formula % 1. Indication of the case 1988 Special V! Application No. 76633 2 Title 8 of the invention! Relationship between the rippleless motor 3 and the ossicles of the person making the correction Patent applicant u Place 1-12 W, Akasaka 11-me, Minato-ku, Tokyo (Fura L4
Su7yo name (242) Shibaura Chisakusho Co., Ltd. 1, spontaneous correction: 1), supplementary burning elephant w4! and details-6, content of amendment

Claims (1)

[Claims] A brushless motor consisting of a magnetic wire wound around the outer periphery of a cylindrical coil containing a permanent magnet rotor, characterized by having less winding at both ends in the axial direction and a larger winding at the center. motor.