JPH05344700A - Cylindrical coreless motor - Google Patents

Abstract

PURPOSE:To lower a power consumption by loading a bearing from the external side of a metal holder to the larger diameter portion and arranging a cylindrical magnet to the smaller diameter portion. CONSTITUTION:A metal holder is formed in two stages consisting of a larger diameter portion and a smaller diameter portion. A bearing 3 is loaded externally to the larger diameter portion 12 and a cylindrical magnet 14 is arranged at the smaller diameter portion. A vibration type cylindrical coreless motor may be formed with a metal holder which is integrally raised by reversely squeezing the closed bottom of cylindrical case 11 toward the internal side and a shaft 7 which is formed by integrating an eccentric weight 16 to a load holder 18 at the one end of the cylindrical winding 15 so that the shaft 7 is no longer projected toward the outside of the case 11. Thereby, the built-in cylindrical magnet 14 can be formed thicker and a low power consumption can be realized because operating point permeance coefficient can be increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylindrical coreless motor used as a silent call means of a wireless calling device (pager).

[0002]

2. Description of the Related Art Conventionally, a cylindrical coreless motor used for silent call means such as a pager has an eccentric weight W made of a tungsten alloy on an output shaft S of a motor body M as shown in FIG. It is known that vibration is generated by utilizing the difference in centrifugal force of the weight W, and only the person carrying the vibration is notified by the vibration.

The internal structure of this conventional cylindrical coreless motor M is, as shown in FIG. 4, a metal holder 2 machined with free-cutting steel or the like is planted in the bottom of a bottomed cylindrical case 1, and two metal holders are provided inside the metal holder 2. Bearings 3 and 3 are arranged, and a cylindrical magnet 4 is arranged on the outer diameter thereof, and a cylindrical coreless winding 5 is made to face the space between the cylindrical magnet 4 and the case 1, and the commutator integrated The rotor holder 6 is integrally molded with the rotor holder 6 and rotatably held on the bearings 3 by the shaft 7.

In the figure, numeral 8 is a pair of brushes and a commutator 9
The brush 10 is attached to the opening edge of the case 1 by sliding it onto the case 1.

[0005]

As can be understood from the drawings, the above-mentioned conventional structure is such that the metal holder 2 is housed inside the cylindrical magnet M, and the shaft 7 is housed in the metal holder 2 via the bearings 3 and 3. Therefore, the thickness of the cylindrical magnet cannot be increased, the operating point permeance coefficient becomes small, the air gap magnetic flux density becomes small, the current consumption becomes large, and there is a problem of battery consumption as a portable device.

The present invention is intended to propose a structure that solves the above-mentioned problems, and provides a cylindrical coreless motor with a low current consumption even if it is made thinner.

[0007]

According to the present invention, in a cylindrical coreless motor having a cylindrical case in which a metal holder rises inward from one end, the metal holder is formed in two stages of a large diameter and a small diameter, Bearings are attached to the large diameter part from the outside, and a cylindrical magnet is arranged in the small diameter part.
The metal holder is formed by squeezing the bottom of the bottomed cylindrical case inward and raising it integrally.The shaft holder does not protrude outside the case, and the eccentric weight is attached to the rotor holder at one end of the cylindrical winding. Alternatively, a vibration type cylindrical coreless motor may be integrated.

[0008]

By doing so, the built-in cylindrical magnet can be made thicker, and the operating point permeance coefficient is increased, resulting in low current consumption.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a sectional view of an essential part of a vibration motor having a built-in eccentric weight as a cylindrical coreless motor as a first embodiment of the present invention, showing an elongated bottomed cylindrical case 11 constituting a housing. Large diameter part 12 with the bottom inward
And the small-diameter portion 13 are squeezed into two stages and erected integrally, and the bearing 3 is mounted on the large-diameter portion 12 from the outside by press fitting and the cylindrical magnet 14 is arranged on the small-diameter portion 13 by adhesion or the like. To do.

In the space between the cylindrical magnet 14 and the cylindrical case 11, a rotor R composed of a cylindrical winding 15 is arranged. At one end of the rotor R, a rotor holder 18 in which the eccentric weight 16, the commutator 17, and the shaft 7 are integrally molded is fixed by adhesion or the like.

One end of the shaft is rotatably attached to the bearing 3 in the center of a brush base 19 fitted by caulking or the like to the opening edge of the cylindrical case so that one end of the shaft does not protrude outward. Supported by. Commutator 17
Brushes 20 and 20 planted in the brush base 19
Slide against each other with an appropriate pressing force, and the base end of this brush base 19
Is extended to the outside to serve as a power supply terminal.

In the figure, reference numeral 21 denotes a washer 22 arranged between the rotor holder 18 and the cylindrical magnet 14, and a washer 22 is a contact plate arranged for pivotally supporting the tip of the shaft 7. Reference numeral 23 is a guide for determining the pole position of the cylindrical magnet arranged in the large diameter portion 12.

FIG. 2 is a sectional view of the essential parts of an embodiment in which the present invention is applied to a normal rotation type cylindrical coreless motor.
Since the shaft 7 is projected outward and the eccentric weight 16 is not provided, detailed description thereof will be omitted.

[0014]

Since the present invention is configured as described above, it is not necessary to dispose the bearing inside the cylindrical magnet, and the wall thickness of the magnet can be increased. Therefore, the operating point permeance coefficient can be increased. Therefore, low current consumption can be obtained. Therefore, with the same characteristics, it is possible to reduce the diameter of the motor.

The rising portion composed of a large diameter portion and a small diameter portion has been shown as the one in which the bottom portion of the bottomed case is integrated, but it may be separately formed by cutting or the like and fitted. Of course.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of essential parts of a first embodiment of a cylindrical coreless motor of the present invention applied to a vibration motor.

FIG. 2 is a sectional view of an essential part of a second embodiment of the motor applied to a normal rotary type motor.

FIG. 3 is a perspective view of a conventional cylindrical coreless motor used as a vibration motor.

FIG. 4 is a cross-sectional view of essential parts showing the internal structure of the motor shown in FIG.

[Explanation of symbols]

 11 bottomed cylindrical case 12 large diameter part 13 small diameter part 14 magnet 15 cylindrical winding 16 eccentric weight 17 commutator 3 bearing

Claims (3)

[Claims] 1. A cylindrical coreless motor having a cylindrical case in which a metal holder rises inward from one end, and the metal holder is formed in two stages of a large diameter and a small diameter, and a bearing is externally provided in the large diameter portion. A cylindrical coreless motor that is mounted and has a cylindrical magnet on the small diameter part. 2. The cylindrical coreless motor according to claim 1, wherein the metal holder is formed integrally by squeezing the bottom of the bottomed cylindrical case inward. 3. The cylindrical coreless motor according to claim 1 or 2, wherein the eccentric weight is integrated with the rotor holder at one end of the cylindrical winding so that the shaft does not protrude to the outside of the case.