JPH07231466A - Vibrator for vibration generator for small radio call device - Google Patents

Abstract

PURPOSE:To make the size of the entire vibration generator small and to make the weight light by forming a mount hole to which a motor shaft is inserted to an eccentric position and selecting a thickness of the mount hole in the axial line direction so as to be thicker gradually from the axial line toward its gravity center. CONSTITUTION:A mount hole 11 to which motor shaft is inserted is formed to an eccentric position of a vibrator 10. Then the thickness of the mount hole 11 in the axial line C is selected continuously from the axial line C toward the gravity center of the vibrator 10 in a concaved circular arc. The gravity center is offset remarkably toward an outer circumference in the vibrator 10 as above. Since the distance between the gravity center and the axial line C is much increased, a large vibration is obtained when the vibrator 10 is rotated. As a result, the entire vibrator is made light in its weight.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibrator mounted on a vibration generator of a small wireless calling machine.

[0002]

2. Description of the Related Art In recent years, as a type of a paging type small-sized wireless interrogator, a type having a built-in vibration generator in which a vibrator made of a metal of high specific gravity is eccentrically fixed is becoming popular as a rotary shaft of a motor. In a device having such a built-in vibration generator, the vibration is generated by the vibrator instead of making a ringing sound, thereby making it known to others even when crowded or during a meeting, for example. There is an advantage that the reception can be confirmed without being blocked.

FIG. 4 shows an example of a conventional vibration generator to which a vibrator of this type is attached. In FIG. 4, reference numeral 1 in the figure indicates a small motor connected to a signal generation circuit of a small wireless device. The rotating shaft 2 of the motor 1 has a fan shape and has a predetermined thickness in the axial direction. The rotary shaft 2 is inserted into the mounting hole 4 formed at the eccentric position, and is fixed to the rotary shaft 2 by caulking at one point on the outer peripheral portion. The above-mentioned conventional vibrator 3 includes W powder, Ni powder, Cu powder, or F powder.
e Powders and the like are appropriately mixed and then formed into a desired fan-shaped plate by the powder metallurgy method (dry press molding method), which is made of a so-called high specific gravity metal having a specific gravity of about 17 to 19 g / cm ³ . By the way, in the above-mentioned conventional vibration generator, the outer diameter of the casing of the motor 1 is 6 to 12 mm, and as the vibrator 3, the length of the mounting hole 4 in the axis C direction is 3 to 12 mm. The maximum radius R from C to the outer circumference has a dimension in the range of 2.5 to 5.5 mm,
It is fixed to the rotary shaft 2 of the motor 1.

[0004]

By the way, in recent years, in such a vibration generator, there is an increasing demand for downsizing or thinning of the entire device. Therefore, in order to downsize or reduce the thickness of the vibration generator itself, it is necessary to downsize the motor 1.
As a result, the maximum radius R of the vibrator 3 must be reduced. However, in this type of vibrator 3, a desired vibration is obtained by the centrifugal force generated at the time of rotation due to the amount of eccentricity with the axis C of the motor rotation shaft 2. Therefore, if the maximum radius R is reduced, the vibrator 3 There is a problem that the distance between the center of gravity and the axis C becomes small, the centrifugal force generated as a result becomes small, and the required vibration amount cannot be obtained.

On the other hand, as shown in FIG. 5, as another conventional vibrator 5, the thickness of the outer peripheral side of the motor rotating shaft 2 is larger than that of the axis C side of the motor rotating shaft 2 via the step portion 6. Some are molded like this. According to the vibrator 5, since the weight on the outer peripheral side is larger than that shown in FIG. 4, the center of gravity thereof is located on the outer peripheral side, so that the vibration which is slightly larger than that of the vibrator 3 is generated. The amount is obtained. However, in the vibrator 5, stress concentration occurs at the base end portion 7 of the stepped portion 6 when the vibrator 5 is formed by press molding or is used, and cracks easily occur, which is not practical. Has a problem that it is not suitable for this type of vibrator.

The present invention has been made in order to effectively solve the problems of the above-mentioned conventional vibrators. With the miniaturization of motors, the desired vibration amount can be obtained even when the motor itself is made small in diameter and light in weight. It is an object of the present invention to provide a vibrator for a vibration generator of a small-sized wireless interrogator capable of obtaining the above.

[0007]

A vibrator for a vibration generator of a compact wireless interrogator according to the present invention has a mounting hole into which an axis of rotation of the motor is inserted, and an axis line of the mounting hole. The thickness dimension in the direction is formed so as to gradually increase from the axis to the center of gravity thereof. Here, the thickness dimension in the axial direction of the mounting hole may be formed so as to gradually increase from the axis toward the center of gravity thereof, or from the axis toward the center of gravity thereof, You may form so that it may become large gradually through several step parts.

[0008]

In the vibrator for a vibration generator of a small radio caller having the above-described structure, the thickness of the vibrator is gradually increased from the rotation axis toward the center of gravity. Is significantly biased toward the outer circumference side compared to the conventional one. Therefore, since the distance between the center of gravity and the rotation axis becomes extremely large, a large amount of vibration can be obtained when rotating the center of gravity. As a result, even when the motor is downsized and the maximum radius of the vibrator is further reduced, sufficient vibration can be obtained, so that the vibration generator as a whole can be easily downsized or thinned. It will be possible.

[0009]

1 and 2 show an embodiment of a vibrator for a vibration generator of a small wireless calling machine according to the present invention. In these figures, the vibrator 10 is a fan-shaped front view made of a super-polymerized gold material having a specific gravity of about 17 to 19 g / cm ³ which is molded by an injection molding method, and the rotation shaft of the motor is inserted at the eccentric position. The mounting hole 11 is formed. In this vibrator 10, the thickness dimension of the mounting hole 11 in the direction of the axis C is continuous in a concave arc shape from the axis C toward the center of gravity of the vibrator 10, as shown in FIG. It is formed so as to gradually increase.

Here, as described above, in the vibrator 10 having such a complicated shape, it is desirable that the vibrator 10 is molded by the injection molding method. Therefore, the oscillator 1
The injection molding method for molding 0 will be described. First, a predetermined amount (about 40% by volume) of a binder is added to W powder, Ni powder, Cu powder, Fe powder, or the like, and appropriately mixed, and then 100 to 2000 kgf. It is preferable to mold the vibrator 10 by injection molding at an injection pressure of / cm ² , debinding and sintering.

In the above injection molding method, the injection pressure is set to 100.
~ 2000kgf / cm ² is because this injection pressure is 100
If it is less than kgf / cm ² , unfilled part called so-called short shot occurs in the molded product and it is not suitable. Conversely, if the injection pressure exceeds 2000 kgf / cm ² , the molded product will protrude from the mold. This is because the friction between the mold and the mold becomes too large and the molded product is damaged or deformed, which is inconvenient. In this way, 100 to 20 lower than the normal press molding pressure (2500 to 4000 kgf / cm ² ).
By molding with injection pressure in the range of 00 kgf / cm ² ,
The vibrator 10 having a complicated shape of this kind can be molded with high dimensional accuracy without causing cracks.

In the vibrator 10 for the vibration generator having the above-described structure, the rotary shaft of the motor is inserted into the mounting hole 11 and is fixed to the motor rotary shaft by caulking at the outer peripheral portion at a plurality of positions in the axial direction. And is used as a vibration generator. Therefore, such a vibrator 10
According to this, since the thickness dimension is formed so as to gradually increase from the rotation axis C toward the center of gravity, the position of the center of gravity is greatly deviated to the outer peripheral side compared to the conventional one. Therefore, since the distance between the center of gravity and the rotation axis C becomes extremely large, a large amount of vibration can be obtained when rotating the center of gravity. As a result, even when the motor is downsized and the maximum radius of the vibrator is made smaller and lighter,
Since it is possible to obtain sufficient vibration, it is possible to reduce the weight of the entire device, and thus it is possible to extremely easily reduce the size or the thickness of the entire vibration generating device to which the vibrator 10 is attached. Become. In addition, the oscillator 10
By molding by means of an injection molding method, the vibrator 10 having a complicated shape of this kind can be molded with high dimensional accuracy without causing cracks.

FIG. 3 shows another embodiment of the vibrator for a vibration generator of a small radio calling device according to the present invention. In this vibrator 20, the thickness dimension of the mounting hole 21 in the direction of the axis C is shown. However, it is formed so as to gradually increase from the axis C toward the center of gravity of the vibrator 20 via a plurality of step portions 22. Therefore, also with such a vibrator 20, it is possible to obtain the same effects as those of the first embodiment. In addition, since the vibrator 20 is formed so that the thickness dimension is gradually increased by the plurality of step portions 22, stress is applied to the base end portion 7 of one step portion 6 as shown in FIG. There is no risk of cracks concentrating on.

[0014]

As described above, the vibrator for a vibration generator of a compact wireless interrogator according to the present invention forms a mounting hole into which the rotary shaft of the motor is inserted at an eccentric position, and the mounting hole Since the thickness in the axial direction was gradually increased from the axis toward the center of gravity, the center of gravity was rotated so that the position of the center of gravity was significantly biased toward the outer peripheral side compared to the conventional one. Sometimes a large amount of vibration can be obtained. Therefore, even if the motor is downsized and the maximum radius of the vibrator is made smaller to reduce the weight, sufficient vibration can be obtained. It becomes possible to extremely easily reduce the size and weight or reduce the thickness.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an embodiment of a vibrator for a vibration generator of a compact wireless interrogator according to the present invention.

FIG. 2 is a front view showing the vibrator of FIG.

FIG. 3 is a vertical sectional view showing another embodiment of the present invention.

FIG. 4 is a vertical sectional view showing a state in which a conventional vibrator is attached to a motor.

FIG. 5 is a vertical cross-sectional view showing a state in which another conventional vibrator is attached to a motor.

[Explanation of symbols]

 1 Motor 2 Motor Rotating Shaft 10, 20 Vibrator 11, 21 Mounting Hole 22 Step C Axis

Claims (3)

[Claims] 1. A vibrator for a vibration generator of a small wireless interrogator, which is eccentrically fixed to a rotation shaft of a motor, wherein a mounting hole into which the rotation shaft of the motor is inserted is formed at an eccentric position. A vibrator for a vibration generator of a small-sized wireless calling machine, characterized in that the thickness of the mounting hole in the axial direction is gradually increased from the axis toward the center of gravity thereof. 2. The thickness dimension of the mounting hole in the axial direction is formed so as to be continuously and gradually increased from the axis toward the center of gravity thereof. A vibrator for a vibration generator of a small wireless caller. 3. The thickness dimension of the mounting hole in the axial direction is formed so as to gradually increase from the axis toward the center of gravity thereof through a plurality of steps. 1. A vibrator for a vibration generator of a compact wireless interrogator according to 1.