JPS6292752A - Structure of rotor - Google Patents

Abstract

PURPOSE:To improve reliability, by providing the outer peripheral section of the magnet of a rotor section, with a toothed gear for rotational force transmission. CONSTITUTION:So far as a plane confronting type brushless motor is concerned, a coil 2 is fixed on a substrate 1, and a housing 3 is fixed on the central section. Besides, on a bearing 4 set on the housing 3, a rotor 6 and an output shaft 5 with the fitted rotor are rotatably supported. Then, on the outer peripheral section of the rotor 2, a toothed gear section 6a for output transmission is formed in a specified shape, and on the upper end surface section of the rotor 6, a rotor yoke 7 is fixed to construct a magnetic route. For the rotor 6, the magnetic substance of plastic magnet material is used, and a main magnet section 6b and a toothed gear section 6a are produced in a molding process at the same time. Then, the toothed gear for output transmission is not needed to be separately fitted on the output shaft 5, and the output shaft 5 is shortened, and a thin type motor can be produced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the structure of the rotor of a thin and small brushless motor used in headphone stereos, VTRs, VDs, or 0Afi devices.

[Conventional technology]

BACKGROUND ART Conventionally, there has been a demand for a rotor structure used in this type of motor that can be used to construct a thin motor, that is, one having a short length in the direction of the output shaft. On the other hand, in the conventional motor, the output transmission parts were separately fixed in the longitudinal direction of the output shaft at the final stage of completion of the motor IIv.

[Problem that the invention seeks to solve]

In the conventional rotor structure described above, the output transmission parts are attached separately in the longitudinal direction of the output shaft, so the total length of the output shaft becomes correspondingly longer, and therefore the motor also becomes longer, which makes it difficult to manufacture thin motors. That was a problem.

An object of the present invention is to provide a rotor structure that allows the output shaft to be shortened and a thin and small motor to be manufactured by directly attaching a rotational force transmitting gear to the magnet portion of the rotor.

[Means for solving problems]

The means of the present invention for solving the above problems is to provide a rotor in which a disc-shaped magnet magnetized with multiple poles in the direction of the output shaft is fixed to the shaft, and a gear for transmitting rotational force is installed on the outer periphery of the magnet in the same manner as the magnet. The rotor structure is characterized by being integrally molded with a material, and the gear part for transmitting rotational force is made of a non-magnetic metal material, and the magnet part is made of a plastic magnet material when the gear part is molded. It is also possible to integrally configure the rotor.

[Effect]

Since the present invention forms a gear for transmitting rotational force on the outer periphery of the magnet part of the rotor, there is no need to separately attach output transmission parts to the output shaft, and therefore it is possible to shorten the output shaft and manufacture a thin motor. .

〔Example〕

Next, the present invention will be described by way of examples with reference to the drawings.

FIG. 1 is a sectional view of a planar brushless motor using an embodiment of the present invention. In this figure, a coil 2 is fixed at a predetermined position on a substrate 1, and a housing 3 is also fixed to the substrate 1 at the center of the coil 2. A bearing 4 disposed in the housing 3 rotatably supports a rotor 6 and an output shaft 5 on which the rotor 6 is mounted. A stomp ring 8 is fixed to one end (lower side in the figure) of the output shaft 5 and contacts six ends of the bearing 4 to adjust the rattling of the rotor 6 in the thrust direction. A disc-shaped rotor 6 is fixed to the other end (the upper end in the figure) of the output shaft 5, and an output transmission gear part 6a is formed in a predetermined shape on the outer periphery of the rotor 6. A rotor yoke 7 is fixed to the upper end surface of the rotor 6 and forms a magnetic path. This rotor 6 uses a magnet material made of a moldable material made by mixing a material called plastic magnet material that is made of a fine magnet material and a plastic material (mainly nylon resin) called PAINK, and the main magnet part 6b and When manufacturing the gear part 6a and the magnet (
It was produced by simultaneous molding during the production of Rotor 6), and mass molding is possible just by considering the mold. On the electrical board 1 are lands (
(not shown) is provided. FIG. 2 is a diagram of the rotor 6 seen from the yoke side, and shows the output shaft 5. A gear 6a and a yoke 7 are attached to the outer circumference of the rotor. During mass production, the yoke 7, the gear nets (6, 6a) (gear-containing portion), and the output shaft 5 can be integrally molded at the same time depending on the mold. The main magnet portion (rotor 6) may be magnetized in a portion corresponding to the coil, and the direction thereof is the direction of the coil, that is, the direction of the thickness of the magnet. Since the gear portion 6a provided in this structure is made of a plastic material, it is inevitably inferior to a metal gear in terms of mechanical strength and wear resistance, so a system as shown in the embodiment shown in FIG. 3 was invented. FIG. 3 shows a state in which the yoke has been removed, and the gear lO is manufactured from a non-magnetic metal material by die-casting or cutting, and is integrated with the main magnet 113 when molding to form the rotor. Reference numeral 11 indicates a plurality of enclosing prevention protrusions into which the plastic magnet material of the main magnet flows to improve the strength of the integral holding force.

FIG. 4 shows still another embodiment of the present invention, and is a plan view of a two-stage geared rotor viewed from the yoke side. This rotor has a first stage gear 21, a second stage gear 22. York 23
, and a shaft fixing hole 24 is bored therein. In this way, the type may be considered depending on the application, which can be applied to a multi-stage geared rotor.

〔Effect of the invention〕

As explained above, the present invention has gears for transmitting rotational force on the outer periphery of the magnet of the rotor, so there is no need to add a transmission mechanism on the output shaft when the motor is completed, as in the conventional case, and the thickness can be reduced. It can be said that it is a type that can be mass-produced with highly reliable motors because it does not increase the number of motors and can be securely fixed without using an adhesive like the conventional type due to its integrated structure with the output shaft. Further, the rotor according to the present invention can be used in the same manner as the conventional rotor, since it has the same function as the conventional rotor if the gear portion is not used.

Furthermore, if a rotor having multiple stages of gear parts is prepared as required, the gear ratio can be selected and used depending on the application.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a sectional view of one embodiment of the present invention, FIG. 2 is a plan view of one embodiment of the present invention, and FIG. 3 is a plan view of another embodiment of the present invention. FIG. 4 is a plan view of still another embodiment of the present invention. ■... Board, 2... Coil, 3...
Housing, 4...Bearing, 5...Main shaft,
6... Heater, 6a... Gear part,
7... York.

Claims (2)

[Claims] (1) The rotor has a disc-shaped magnet magnetized with multiple poles in the output shaft direction fixed to the shaft, and a gear for transmitting rotational force is integrally molded on the outer periphery of the magnet using the same material as the magnet. The structure of the rotor. (2) The gear part for transmitting rotational force is made of a non-magnetic metal material, and the magnet part is made of a plastic magnet material and when molded, the gear part is integrally constructed as a rotor. The structure of the rotor described in scope 1.