JP2907796B2 - Vibration generator for small radio - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration generator used for calling a small wireless device such as a cellular phone.

[0002]

2. Description of the Related Art In recent years, as a kind of a small paging-type wireless paging apparatus, a type in which a vibration generating device in which a vibrator made of a metal having a high specific gravity is eccentrically fixed to a rotating shaft of a motor is becoming widespread. In a device incorporating such a vibration generating device, vibration is generated by the vibrator instead of generating a ringing sound, so that, for example, even when crowded or during a meeting, it is known to others. There is an advantage that reception can be confirmed without being received.
FIG. 12 and FIG. 13 show a conventional vibration generator for a small radio device of this type. A small motor 1 connected to a signal generation circuit of the small radio device and a rotating shaft 2 of the motor 1 Vibrator 4 fixed via brass bush 3
It is provided with.

The vibrator 4 is made of a metal having a high specific gravity formed by a powder metallurgy method, and has a load eccentric to the bush 3. Since the rotating shaft 2 and the vibrator 4 have poor adhesive wettability, and therefore, the rotating shaft 2 and the vibrator 4 cannot be directly connected with the adhesive, the bush 3 made of brass is first used. After being fixed to the rotary shaft 2 by press-fitting, the vibrator 4 having good wettability with the adhesive is fixed to the bush 3 with a sufficient adhesive force. Then, the vibrator 4 having an eccentric load vibrates by being rotationally driven by the motor 1, and this vibration allows a wearer to know reception by the small wireless device.

However, in the above-mentioned conventional vibration generator, the rotary shaft 2 and the vibrator 4 must be connected via the bush 3, so that the number of parts is large and the number of manufacturing steps is large, which is uneconomical. There was a problem. When the vibrator 4 is reduced in diameter due to a demand for downsizing of the vibration generator, the outer diameter of the rotating shaft 2 is reduced
The diameter of the vibrator 4 becomes relatively large due to the sum of the thickness of the vibrator 4 and the thickness of the vibrator 4. As a result, the position of the center of gravity of the vibrator 4 approaches the rotating shaft 2 side, and the amount of generated vibration decreases. There was a problem.

Therefore, as shown in FIG. 14 and FIG. 15, a structure in which the vibrator 4 is directly fixed to the rotating shaft 2 by caulking is being adopted. This vibrator 4
Is composed of a cylindrical boss portion 42 having a mounting hole 41 fitted to the rotating shaft 2 and an eccentric load portion 43 formed integrally with the boss portion 42. Caulking toward the rotating shaft 2 side by the directional load P1, or the lateral load P2 orthogonal to the longitudinal load P1
The vibrator 4 is directly fixed to the rotating shaft 2 by caulking toward the rotating shaft 2.

[0006]

However, in the conventional small-sized radio device vibration generating device shown in FIGS. 14 and 15, when the boss portion 42 is swaged by the vertical load P1 or the horizontal load P2, the boss portion 42 is moved in the circumferential direction. Therefore, there is a problem that the gap between the mounting hole 41 and the rotating shaft 2 becomes large in portions other than the caulked portion. Also, after caulking, the mounting hole 41 is slightly rotated by the
It may move away from it. For this reason, there is a problem that a large pulling force cannot be obtained with respect to the integration of the rotating shaft 2 and the vibrator 4.

On the other hand, in accordance with the demand for further miniaturization in recent years, the maximum diameter (radius) of the vibrator 4 has been reduced to about 5 mm.
From about 3 mm to about 3 mm.
There is a need to reduce the diameter of the metal to 1 mm or less.
In such a case, if the thickness of the vibrator 4 around the rotating shaft 2 is reduced in order to secure a desired amount of vibration, that is, the amount of eccentricity in the vibrator 4, the vibrator 4 is a powder molded product and has toughness. In addition, the surface pressure acting on the mounting hole 41 from the rotating shaft 2 at the time of crimping becomes high, and the crimping forms a concave portion, and the concave portion becomes extremely thin. There is a problem that the thin boss portion 42 is extremely easily cracked against the vertical load P1 and the horizontal load P2 toward the shaft 2. Also, in particular,
When caulking by the lateral load P2, the boss 42
Is required to be held by a jig or the like from the side opposite to the load P2, but the outer peripheral portion for holding the boss portion 42 has become narrower with downsizing, and thus there is a problem that the caulking operation itself becomes extremely difficult. Was.

SUMMARY OF THE INVENTION The present invention has been made to effectively solve the problems of the above-described conventional vibration generating device for a small wireless device. Even when the vibrator is reduced in diameter, the boss portion is not cracked. It is an object of the present invention to provide a vibration generator for a small wireless device that can be integrated with a rotating shaft with a sufficiently large pulling force and that can perform the caulking operation extremely easily.

[0009]

According to a first aspect of the present invention, there is provided a vibration generating apparatus for a small wireless device according to the present invention, wherein a vibration device is integrally attached to a rotating shaft of a motor by caulking. In the generator, the vibrator includes a boss having a mounting hole to be fitted to the rotating shaft, and an eccentric load portion formed integrally with the boss, and the vibrator Is the outer circumference of the boss ,
One side of the center of the rotation axis, closer to the center of gravity of the vibrator.
It is characterized by being fixed to the rotating shaft by caulking from the position toward the eccentric load portion side.

[0010]

According to the first aspect of the present invention, the vibrator is fixed to the rotating shaft by caulking from the outer periphery of the boss toward the eccentric load portion, so that the vibrator is plastically deformed by the caulking. The mounting boss presses the mounting hole toward the rotation shaft by the boss portion. As a result, a portion covering substantially the entire circumference of the mounting hole comes into close contact with the rotation shaft with a predetermined surface pressure.
Moreover, at this time, the mounting hole is not displaced away from the rotating shaft by the springback, so that the rotating shaft and the vibrator can be integrated with a sufficiently large pulling force.

Further, since almost the entire circumference of the mounting hole presses the rotating shaft, even if the rotating shaft becomes thin, a large surface pressure does not act locally on the mounting hole from the rotating shaft. Therefore, it is possible to prevent the boss portion from cracking, and it is possible to position the center of gravity of the entire vibrator on the outer peripheral side of the eccentric load portion by reducing the thickness of the boss portion. It becomes possible to secure. Further, since the caulking is performed toward the eccentric load portion side, when performing the caulking process by the punch, the length dimension of the outer peripheral portion may be held at a large eccentric load portion. The rotating shaft and the vibrator can be integrated.

Further, since the caulking is performed from a position on the outer periphery of the vibrator and offset from the center of the rotating shaft toward the center of gravity of the vibrator toward the eccentric load portion, the boss is formed. A concave portion is not formed in the thin portion of the portion, and since the excess portion can be sufficiently moved to the mounting hole side by the formation of the concave portion, the rotating shaft and the vibrator are moved with a larger force. It becomes possible to integrate them.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) Hereinafter, an embodiment of a vibration generator for a small wireless device according to the present invention will be described with reference to FIGS. Elements common to those of the conventional example shown in FIGS. 14 and 15 are denoted by the same reference numerals, and description thereof will be simplified. In FIGS. 1 and 2, the vibration generating device of this small wireless device applies a vibrator 4 to the eccentric load portion 43 side by a punch 5 at a boundary 4a between the boss portion 42 and the eccentric load portion 43. It is integrated by tightening. The caulked portion 4a deforms at least the eccentric load portion 43, thereby pressing the mounting hole 41 against the rotating shaft 2 with the moved meat portion, and fixing the vibrator 4 to the rotating shaft 2 by the pressing force. Has become. Here, the caulked portion 4a is located at a substantially central position in the thickness direction of the eccentric load portion 43.

Here, the eccentric load portion 43 has two radial side surfaces 4 extending radially outward from the cylindrical boss portion 42.
31 and an arcuate outer surface 432 formed coaxially with the center line C of the boss portion 42. The two radial side surfaces 431 are formed so as to be located on a plane passing through the center line C of the mounting hole 41, and the boss portion 42 projects one of the cylinders after being bisected from the radial side surface 431. It has a shape that has been made. Also, the arc-shaped outer surface 432 is 2
It has one shape of a bisected circle having two radial side surfaces 431 as diameters. By the way, the radius R of the mounting hole 41
1 is 0.3 to 0.4 mm, the radius R2 of the boss portion 42 is 0.8 to 1.0 mm, and the radius R3 of the eccentric load portion 43 is 2 to
It is formed to 3 mm.

The vibrator 4 is made of a W—Ni-based
Ni-Fe system, W-Ni-Cu system, or W-Mo-
It is formed by a powder metallurgy method using a superpolymerized gold material having a specific gravity of about 17 to 19 g / cm ³ , such as a Ni—Fe system. Specifically, a mixed powder having a composition consisting of W powder; 89 to 98% by weight and Ni powder; 1.0 to 11% by weight; 0.1-6 wt%, Mo powder; 0.1-6 wt% and Co powder;
A powder mixture having a composition containing 0.1 to 5% by weight of one or more kinds is molded into a fan shape at ¹ ton / cm ² to ⁴ ton / cm ² , and the green compact is formed at 0 ° C. After liquid phase sintering in a hydrogen stream with a dew point of −60 ° C. or in an ammonia decomposing gas, further in a temperature range of 700 ° C. to 1430 ° C. ± 30 ° C. in a vacuum, neutral or reducing atmosphere. After heating, at least 40 ° C / m up to 300 ° C
In this case, a heat treatment of quenching at a cooling rate of at least in is performed.

The reason for limiting the content of each composition as described above is that, when the amount of W (tungsten) exceeds 98% by weight, the malleability is reduced, and cracks are generated during caulking, which is unsuitable. On the other hand, if it is less than 89% by weight, a predetermined specific gravity cannot be obtained, which is inconvenient for this type of vibrator. Also, when the amount of Ni (nickel) exceeds 11% by weight, a predetermined specific gravity cannot be obtained, and when the amount is less than 1.0% by weight, sinterability does not progress.
Further, Co (cobalt) has the same effect as Ni, but if it is less than 0.1% by weight, a sufficient effect of addition cannot be obtained, and if it exceeds 5% by weight, a corresponding effect cannot be obtained. It is uneconomical in manufacturing. Further, Cu powder and Fe powder are
Although the sintering temperature can be lowered by including these, the specific gravity cannot be obtained when the sintering temperature is higher than the above upper limit value. Therefore, the sintering temperature is limited to the above range.

When caulking from the location 4a by the punch 5, as shown in FIG. 1, the eccentric load portion 43 is held by a jig 6 having a groove 61. Here, the groove 61 is provided with a stopper portion 61 a for preventing the eccentric load portion 43 from rotating.

In the vibration generating apparatus for a small wireless device configured as described above, the caulking is biased toward the outer periphery of the vibrator 4 and toward the center of gravity of the vibrator 4 with respect to the center of the rotating shaft 2. The mounting hole 41 is pressed against the rotating shaft 2 by the moved meat portion, and the rotating shaft 2 is pressed substantially all around the mounting hole 41. Can be. Moreover, the mounting hole 41 is not displaced in the direction away from the rotating shaft 2 due to the springback. Therefore, the rotating shaft 2 and the vibrator 4 can be firmly integrated. By the way, in the vibrator 4 having the above dimensions, if the pulling force is 5 kg or more,
In this embodiment, a pull-out force of 8 to 10 Kg was obtained, while the performance was sufficiently high for practical use.

Further, since almost the entire circumference of the mounting hole 41 is pressed against the rotating shaft 2, even if the rotating shaft 2 is narrow as described above, the rotating shaft 2 is locally attached to the mounting hole 41. In addition to the fact that a large surface pressure does not act on the boss portion 42, a concave portion formed by crimping is formed in the thick eccentric load portion 43, so that the boss portion 42 can be prevented from cracking. A large vibration amount can be obtained by forming the eccentricity amount to be thinner and making the eccentric amount large. Furthermore, since it is sufficient to caulk the eccentric load portion 43 side with the punch 5, the caulking can be performed by holding the eccentric load portion 43, and thus the jig 6 having the groove 61 can be used. The plurality of vibrators 4 can be easily held and continuously integrated.

(Embodiment 2) Next, a second embodiment of the present invention will be described with reference to FIGS. In addition,
Elements common to those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. The second embodiment is different from the first embodiment in that the radial side surface 433 is formed in a concave shape on the eccentric load portion 43 side. That is, the radial side surface 433 is located on the center line C of the mounting hole 41.
Is formed in a concave shape with respect to a plane passing through, and the maximum depth L1 is 0.34 mm. The length L2 from the boundary E between the radial side surface 433 and the boss portion 42 to the maximum depth position 433a is 0.55 mm.
The linear length L3 of the radial side surface 433 is 1.4.
mm, the maximum depth position 433a is
It is formed at a position close to the boss portion 42.

The width L4 of the boss 42 is 2.0 m.
m, the height L5 of the boss portion 42 is 1.0 mm, the radius R1 of the mounting hole 41 is 0.41 mm, and the radius R3 of the eccentric load portion 43 is 2.8 mm. The angle A between the plane passing through the center line C and the radial side surface 433 in the outermost peripheral portion is 18 degrees. The diameter D of the punch 5 is 0.75 mm. In the vibration generating device for a small wireless device configured as described above, since the radial side surface 433 is formed in a concave shape, the direction of the load P3 of the punch 5 can be brought into contact with the mounting hole 41. Therefore, the excess meat portion due to swaging from the swaged portion 4a can be more effectively moved to the mounting hole 41. Therefore, the connection strength between the rotating shaft 2 and the vibrator 4 can be further increased.

(Embodiment 3) Next, FIGS.
Shows a third embodiment of the present invention. This third embodiment is different from the first and second embodiments in that one of the radial side surfaces 431 is the same as in the first embodiment. The point is that it is formed in a planar shape, and the other radial side surface 433 is formed in a concave shape as in the second embodiment. Also in the vibration generating device for a small wireless device configured as described above, the caulking is performed from the outer periphery of the vibrator 4 and from the position 4a that is biased toward the center of gravity of the vibrator 4 with respect to the center of the rotating shaft 2. By performing the operation toward the eccentric load portion 43, the same operation and effect as in the second embodiment can be obtained.

Note that, even if the radial side surface 433 is formed in a concave shape as in the second or third embodiment, as shown in FIG. 7 or FIG.
May be integrated by caulking from a portion 4a slightly away from the mounting hole 42. Further, the concave portion 4a formed by the punch 5 may not be formed at the boundary E between the radial side surface 433 and the boss portion 42, but may be formed near the boundary E. However, in that case, as shown in FIG.
The radial side surface 433 (or the radial side surface 43 of FIG. 1)
It is preferable to form it at a position closer to 1). this is,
This is because there is a risk that the boss portion 42 extends in the circumferential direction as the concave portion is formed by the boss portion 42 side.

Further, the swaged portion 4a is provided with the eccentric load portion 4
Although the eccentric load portion 43 is formed at the center in the thickness direction, the eccentric load portion 43 may be swaged at two or more locations 4a at predetermined intervals in the thickness direction. Also,
The caulking may be performed from both sides of the boss portion 42.
Further, the punch 5 may be formed in a triangular prism shape as shown in FIG. 9 and FIG. In this case, since the concave portion formed by crimping is formed in a rectangular shape along the boundary portion E, for example, almost the entire surface of the mounting hole 42 along the axial direction can be pressed against the rotating shaft 2. Therefore, the connection strength between the rotating shaft 2 and the vibrator 4 can be made extremely high. Also, the tip of this punch 5
As shown in FIG. 11, the periphery may be formed in a semicircular arc shape. In this case, since the periphery of the concave portion has an oval shape, the concentration of stress generated in the concave portion can be reduced.

[0026]

As described above, according to the first aspect of the invention, the vibrator has a small diameter by caulking the vibrator from the outer periphery of the boss portion toward the eccentric load portion. In addition, the boss can be integrated with the rotating shaft with a high pulling force without cracking, and the center of gravity of the entire vibrator can be positioned on the outer peripheral side of the eccentric load by thinning the boss. This makes it possible to secure a sufficient amount of vibration.
Further, since no concave portion is formed in the thin portion of the boss portion, and the excess wall portion can be sufficiently moved to the mounting hole side by the formation of the concave portion, the rotating shaft and the vibration shaft can be moved with a larger force. The effect that it becomes possible to integrate with the child is obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a crimped state of a vibrator according to a first embodiment of the present invention.

FIG. 2 shows the shape of the vibrator, and FIG.
Is a front view, and (b) is a side view.

FIG. 3 is a longitudinal sectional view showing a crimped state of a vibrator according to a second embodiment.

FIG. 4 is a front view showing the shape of the vibrator.

FIG. 5 is a longitudinal sectional view showing a crimped state of a vibrator according to a third embodiment.

FIG. 6 is a front view showing the shape of the vibrator.

FIG. 7 is a longitudinal sectional view showing another crimping example of the third embodiment.

FIG. 8 is a longitudinal sectional view showing another crimping example of the second embodiment.

FIG. 9 is a side view showing an example of the punch shown in the first to third embodiments.

FIG. 10 is a front view of the punch.

FIG. 11 is a front end view showing a modified example of the punch shown in the first to third embodiments.

FIG. 12 is a side view of a vibration generator shown as a conventional example.

FIG. 13 is a front view of the vibration generator.

FIG. 14 is a side view of a vibration generator shown as another conventional example.

FIG. 15 is a front view of the vibration generator.

[Description of Signs] 1 Motor 2 Rotating shaft 4 Vibrator 4a Caulking point 41 Mounting hole 42 Boss 43 Eccentric load portion 431, 433 Radial side surface 432 Arc-shaped outer surface 5 Punch C Center line E Boundary portion

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Tatsumi Katsumata 46-1, Chifuku, Susono-shi, Shizuoka Prefecture Higashifuji Manufacturing Co., Ltd. (56) References 184247 (JP, A) JP-A-7-288946 (JP, A) JP-A-8-65948 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H02K 7/065 H04Q 7 / 32

Claims (1)

(57) [Claims] 1. A vibration generator for a small wireless device, comprising a vibrator integrally attached to a rotating shaft of a motor by caulking, wherein the vibrator has a mounting hole fitted to the rotating shaft. And an eccentric load portion formed integrally with the boss portion, and the vibrator is located on the outer periphery of the boss portion and more than the center of the rotation shaft.
A vibration generator for a small wireless device, characterized in that the rotor is fixed to the rotary shaft by being caulked toward a position of the eccentric load portion from a position biased toward a center of gravity of the rotor.