JP3370311B2 - Square DC vibration motor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rectangular DC vibration motor used for a wireless calling device (pager), a silent notification source of a mobile communication device, and the like.

[0002]

2. Description of the Related Art Cylindrical coreless motors as shown in FIG. 4 are known as cylindrical compact DC motors used as silent notification sources such as pagers and alarms. In order to use the motor as a vibration source, a high-density eccentric weight W made of tungsten alloy is arranged on the output shaft S of the motor to generate vibration by centrifugal force during rotation.

[0003]

However, such a cylindrical type has a drawback that it is inconvenient to handle when mounted on a device and must be separately mounted on a printed wiring board or the like through a mounting angle or the like. The flat type motor can be directly fixed to a printed wiring board or the like via a double-sided adhesive tape on the bottom surface or the top surface. Some recent double-sided pressure-sensitive adhesive tapes reach 2 kg per 1 cm of adhesive strength, which is sufficient for practical use. In the case of the air gap type axial motor, the flat type motor is generally disk-shaped in accordance with the shapes of the rotor and magnet used. However, in the case of the radial void type, the magnet becomes thin, the permeance coefficient cannot be made large, and the disk shape is disadvantageous in view of the characteristics.

The object of the present invention is to keep in mind that the occupied space is almost the same whether it is disk-shaped or rectangular on the device side, and it can be mounted on a printed wiring board or the like without the need for a mounting angle or the like. The purpose of the present invention is to provide a small direct-current vibration motor having a rectangular shape aiming at high efficiency by making it a directional air gap type to have a large permeance coefficient.

[0005]

The object of the present invention is, as shown in claim 1, to alternately arrange N and S poles in the case in the radial direction.
A rectangular direct current vibration motor in which a magnetized 4-pole field magnet is arranged, and a rotor arranged inside the magnet via a radial gap is housed in the case (1).
Is formed to have a substantially square cross section, and the magnet (2) is formed so that the center of the magnetic pole substantially coincides with the corner of the case and the inside has a cylindrical space.
However, the rotor itself is biased into this cylindrical space through a radial gap.
Store the centered eccentric rotor in the opening of the case.
This can be achieved by assembling a bracket (8) having a shape . Specifically, as shown in claim 2 and claim 3,
The eccentric rotor is provided on the central core and integrally with the core .
Cored with a plurality of eccentric salient poles arranged eccentrically to one side so as to face via the radial air gap to the magnet on the outer periphery (10), an armature coil wound around the eccentric salient pole in those System, the eccentric rotor is a shaft
Eccentric core supported by (4) and formed eccentric
(3) and a thin insulator (5a) on the outer periphery of this core
It is preferable that the armature coil (5) is arranged in a slotless manner.

As described above, since the case and the bracket have a rectangular cross section , a square flat surface is provided on the device side.
It can be easily fixed to the printed wiring board by using it . Moreover, since the corners are thick, the substantial permeance coefficient is large.
And high efficiency is obtained, as if the sine curve magnetism
Curves are obtained, Ru can be reduced cogging torque.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The construction of an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is applied to a square slotless vibration motor and is shown in a sectional view showing the features of the present invention. Reference numeral 1 is a cylindrical case having a square cross section. A radial field magnet 2 made of rare earth plastic is integrally formed inside. The radial field magnet 2 is magnetized into four equal poles alternately in N and S so that the center of the magnetic pole is at the corner of the case. Reference numeral 3 denotes an eccentric core formed by laminating silicon steel plates arranged inside the field magnet 2 with a radial gap interposed therebetween. Six armature coils are provided with a shaft 4 at the center and a thin insulator 5a at the outer periphery. 5 are arranged to form an eccentric rotor. 3a is the eccentric core in order to emphasize the amount of eccentricity.
3 is a through hole. The eccentric core is non-magnetic,
Alternatively, a weak magnetic synthetic resin may be used, and a weight may be provided inside. Further, the magnet may not be made of rare earth plastic, but may be a rare earth sintered type magnet divided into four parts.

The structure shown in FIG. 2 is such a rectangular direct current module.
Shows the outline of the chromatography data, storing the eccentric rotor, Ke
Incorporate a bracket 8 of the same shape into the opening of the base 1.
It is configured as a square motor and has double-sided adhesion to the printed wiring board 6.
Shows the state of being fixed via the tape 7, whether it is on the bracket side
The terminals 9, 9 protruding from the
The patterns 6a and 6b are connected to supply power.
There is.

FIG. 3 shows an iron core consisting of 6 salient poles.
Cut off the lower half of the three eccentric three salient poles 10 to one side
It has been arranged. The square motor thus configured also has an external shape
Is as shown in FIG. 2, but its description is omitted.
It In this case, since the angle of the field magnet 2 is considerably thicker than that of the end, the sine-curve magnetization curve is obtained even though the permeance coefficient is large, and the cogging torque is reduced although it is an iron core type. To be done.

[0010]

As described above, the present invention has a substantially square outer shape.
Since it is a rectangular DC motor , it can be easily fixed to the printed wiring board by double-sided adhesive tape on the device side. Moreover, since the corners are thick, the permeance coefficient becomes large, and high efficiency can be obtained, and as if a sine curve magnetization curve is obtained, the cogging torque can be reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view applied to a square eccentric slotless vibration motor as one embodiment of the present invention.

FIG. 2 is a perspective view showing an outer shape of an embodiment of a mounting structure for the motor.

FIG. 3 is a transverse cross-sectional view of a main part of another embodiment.

FIG. 4 is a perspective view of a conventional cylindrical small DC motor.

[Explanation of symbols]

1 case 2 field magnet 3 eccentric core 4 shaft 5 armature coil 8 bracket 10 salient pole

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ identification code FI H02K 7/065 H02K 7/065 23/04 23/04 (58) Fields investigated (Int.Cl. ⁷ , DB name) H02K 7 / 065 H02K 23/04

Claims (3)

(57) [Claims] 1. A case is provided in which a 4-pole field magnet magnetized in a radial direction is alternately magnetized in N and S poles, and a rotor arranged inside the magnet via a radial gap is housed. In this rectangular DC vibration motor, the case (1) is formed to have a substantially square cross section, and the magnet (2) is configured such that the center of the field magnetic pole is substantially aligned with the corner of the case and the inside is formed. Shaped to have a cylindrical space
The rotor itself through a radial gap in this cylindrical space
Store the eccentric eccentric rotor in the opening of the case.
A rectangular DC vibration motor with a bracket (8) of the same shape assembled . 2. The eccentric rotor is provided integrally with a central core and the core, and has a radial direction around the magnet .
2. The rectangular direct current according to claim 1, wherein the cored system has a plurality of eccentric salient poles (10) arranged eccentrically on one side so as to face each other through facing air gaps, and an armature coil wound around the eccentric salient poles. Vibration motor. 3. The eccentric rotor is supported on a shaft (4).
With the eccentric core (3) formed eccentric with the
A slotless system comprising an armature coil (5) arranged around a thin insulator (5a).
The described rectangular DC vibration motor.