JPH10313549A - Fixing method of vibrator and vibration generating motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fixing method by which a vibrator can be fixed to a rotary shaft with a sufficient strength even if a motor is constituted with a compact configuration. SOLUTION: In the method for decentering and fixing a block-shaped vibrator 4 having a shaft fixing surface 5 to a rotary shaft 3 of a vibration generating motor 1, a press concave part 7 is formed by compressing with a press piece 11 in the vicinity of a shaft inserting groove 6 of the shaft fixing surface 5 under the state, wherein the rotary shaft 3 is inserted into the shaft inserting groove 6 formed along the shaft fixing surface 5. The rotary shaft 3 is caulked with an inner wall surface 6a of the shaft insetting groove 6 extended to the inside by the formation of the press concave part 7, and the vibrator 4 is fixed to the rotary shaft 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for fixing a vibrator of a vibration generating motor used for a calling function of, for example, a portable communication device, and a vibration generating motor manufactured by using the fixing method.

[0002]

2. Description of the Related Art Conventionally, as disclosed in Japanese Utility Model Publication No. 4-13860 and Japanese Patent No. 2518781, a method of inserting a rotating shaft into a vibrator and caulking the rotating shaft with a mounting member of the vibrator and fixing the rotating shaft is disclosed. 6-48369, a method of press-fitting and fixing a rotating shaft to a vibrator, or
A method of inserting a rotating shaft into a vibrator and fixing the same by welding, as in Japanese Patent Publication No. 96, is known.

[0003]

By the way, the conventional fixing method has an advantage that the vibrator can be securely fixed to the rotating shaft in a short time, but the vibrator requires a mounting member for fixing to the rotating shaft. Become. However, when the size of the motor is reduced and the thickness of the mounting member is reduced, problems such as breakage of the mounting member due to cracks and instability of fixing the vibrator due to insufficient force for caulking the rotating shaft occur.

An object of the present invention is to solve such a problem and to provide a fixing method capable of fixing a vibrator to a rotating shaft with a sufficient force even when the size of the motor is reduced. It is another object of the present invention to provide a vibration generating motor having excellent durability, in which the vibrator is hardly detached from the rotating shaft even when the motor is downsized.

[0005]

According to a first aspect of the present invention, there is provided a method of fixing a vibrator, wherein a block-shaped vibrator having a shaft fixing surface is eccentrically fixed to a rotating shaft of a vibration generating motor. With the rotary shaft inserted into the formed shaft insertion groove, the vicinity of the shaft insertion groove on the shaft fixing surface is compressed with a press piece to form a press recess, and the shaft insertion groove protruding inward due to the formation of the press recess. The rotating shaft is held by the inner wall surface of the first and the vibrator is fixed to the rotating shaft.

In such a configuration, when the press piece is compressed in the vicinity of the shaft insertion groove on the shaft fixing surface with the rotary shaft inserted into the shaft insertion groove, the press piece is buried in the shaft fixing surface in a concave shape. A press recess is formed, and the inner wall surface of the shaft insertion groove close to the press recess protrudes inward. This overhang reduces the width of the shaft insertion groove, and the rotating shaft is sandwiched between the inner wall surfaces of the shaft insertion groove. As a result, the vibrator is securely fixed to the rotating shaft.

In particular, when the size of the motor is reduced, the structure for attaching the vibrator to the rotating shaft becomes fine. For this reason,
For example, in a conventional fixing method of fixing the mounting member through a rotating shaft, the thickness of the mounting member is reduced, and the mounting member is easily damaged. According to the fixing method of the first aspect, a press recess is formed in a vibrator having a very simple structure in which only a shaft insertion groove is formed on a shaft fixing surface, and the rotating shaft is formed by the shaft insertion groove narrowed by the formation of the press recess. It is sandwiched and fixed. For this reason, even if the motor is miniaturized, each part of the vibrator maintains a constant thickness, so that the vibrator is not damaged. As a result, the vibration generating motor in which the vibrator is fixed to the rotating shaft by the fixing method according to the first aspect has high durability even when the motor is downsized.

According to a second aspect of the present invention, the vibrator is characterized in that a cross section orthogonal to the extending direction of the shaft insertion groove has a half-moon shape. When such a configuration is adopted, the center of gravity is shifted toward the outer peripheral direction of the vibrator, so that the centrifugal force generated by the rotation of the vibrator is most advantageous for the generation of vibration.

According to a third aspect of the present invention, there is provided a vibration generating motor, wherein a block-shaped vibrator having a shaft fixing surface is eccentrically fixed to a rotating shaft. A press recess is formed by compressing the vicinity of the shaft insertion groove on the shaft fixing surface with a press piece, and the protrusion is formed on the inner wall surface of the shaft insertion groove by compression with the press piece.

When such a configuration is employed, the width of the shaft insertion groove is reduced by the protrusion formed on the inner wall surface of the shaft insertion groove, and the rotating shaft is sandwiched between the inner wall surfaces of the shaft insertion groove. As a result, the vibrator is securely fixed to the rotating shaft. In particular, as the motor becomes smaller, the structure for attaching the vibrator to the rotating shaft becomes finer. For this reason, for example, in a conventional vibration generating motor in which the vibrator has a mounting member for fixing the rotating shaft, the thickness of the mounting member is reduced, and the mounting member is easily damaged. The vibration generating motor according to claim 3 includes a vibrator having a very simple structure in which the shaft insertion groove is formed on the shaft fixing surface, and the rotary shaft is sandwiched between the shaft insertion grooves narrowed by the formation of the press recess. It is fixed. For this reason, even if the motor is miniaturized, each part of the vibrator maintains a constant thickness, so that the vibrator is not damaged. As a result, the vibration generating motor according to claim 3 has high durability even when the motor is downsized.

According to a fourth aspect of the present invention, the vibrator is characterized in that the cross section orthogonal to the extending direction of the shaft insertion groove has a half-moon shape. When such a configuration is adopted, the center of gravity is shifted toward the outer peripheral direction of the vibrator, so that the centrifugal force generated by the rotation of the vibrator is most advantageous for the generation of vibration.

According to a fifth aspect of the present invention, the shaft insertion groove is an R groove or a U groove having substantially the same diameter as the diameter of the rotating shaft. When such a configuration is adopted, there is almost no gap between the rotating shaft inserted into the shaft inserting groove and the inner wall surface, so that the width of the shaft inserting groove is slightly reduced, and the rotating shaft is The rotating shaft is securely pressed into the shaft insertion groove.

According to a sixth aspect of the present invention, the press concave portion is formed on both sides of the shaft insertion groove and has a trapezoidal cross section wide on the opening side. When such a configuration is adopted, the inner wall surface of the shaft insertion groove projects inward due to the formation of the press concave portion, so that the width of the shaft insertion groove becomes narrowest on the opening side. For this reason, the rotating shaft is securely fixed in the shaft inserting groove, and the rotating shaft hardly comes off the shaft inserting groove.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a perspective view showing a vibration generating motor according to the present embodiment. As shown in FIG. 1, the vibration generating motor 1 includes a vibrator 4 made of tungsten nickel and eccentrically fixed to a rotating shaft 3 of a motor body 2. Vibrator 4
Has a block shape obtained by cutting a cylinder in the axial direction, and this cut surface is used as a shaft fixing surface 5 for fixing the rotating shaft 3.
It has become. A shaft insertion groove 6 penetrating both end surfaces is formed on the shaft fixing surface 5, and a cross section of the vibrator 4 orthogonal to the extending direction of the shaft insertion groove 6 has a half-moon shape. As shown in FIG. 2, the shaft insertion groove 6 has a diameter substantially equal to the diameter of the rotating shaft 3.
The rotary shaft 3 is inserted into the shaft insertion groove 6.
In the vicinity of the shaft insertion groove 6 on the shaft fixing surface 5, a pair of press recesses 7 are compression-molded with the shaft insertion groove 6 interposed therebetween. The press recess 7 has a wide trapezoidal cross section on the opening side, and a protrusion 8 is formed on the inner wall surface 6 a of the shaft insertion groove 6 by compression molding of the press recess 7. The rotating shaft 3 is swaged by the overhang 8, and the vibrator 4 is securely fixed to the rotating shaft 3. Note that the shaft insertion groove 6 may be a U-shaped groove having substantially the same diameter as the diameter of the rotating shaft 3. The width of the shaft insertion groove 6 is about 0.8 mm, and the interval between the pair of press recesses 7 is about 1.
0 mm.

Next, a method of fixing the vibrator according to the present embodiment will be described. As shown in FIG.
Is mounted on the vibrator fixing base 9, and a press member 10 made of tungsten carbide is disposed above the vibrator fixing base 9. A pair of press pieces 11 having a trapezoidal cross section project from the lower end of the press member 10, and the upper end of the press member 10 is fixed to a drive arm (not shown). And
As the drive arm moves up and down, the press member 10 moves up and down.

Since the diameter of the shaft insertion groove 6 is substantially the same as the diameter of the rotary shaft 3, it is only necessary to push the rotary shaft 3 into the shaft insertion groove 6 from one end face of the vibrator 4 as shown in FIG. Thus, the rotary shaft 3 can be easily inserted into the shaft insertion groove 6. Thereafter, as shown in FIG. 4C, when the drive arm is driven to lower the press member 10, the shaft fixing surface 5 of the vibrator 4 is uniformly compressed by the pair of press pieces 11. as a result,
As shown in FIG. 4D, a pair of press recesses 7 are compression-molded on both sides of the shaft insertion groove 6. Further, a pair of overhangs 8 are formed on the inner wall surface of the shaft insertion groove 6 by the compression of the press pieces 11. With these overhangs 8, the rotating shaft 3
Is surrounded by the inner wall surface of the shaft insertion groove 6, and the rotating shaft 3 can be swaged by the inner wall surface of the shaft insertion groove 6. As a result, the vibrator 4 is securely fixed to the rotating shaft 3.

In particular, when the size of the motor is reduced, the structure for attaching the vibrator 4 to the rotating shaft 3 becomes fine. However, the vibration generating motor 1 of the present embodiment has the shaft fixing surface 5
Since the rotary shaft 3 is simply inserted into the shaft insertion groove 6 provided in the motor, the vibrator 4 is not easily damaged by downsizing of the motor. Conventionally, since the rotating shaft is fixed by caulking the mounting member of the vibrator, the mounting member having a reduced thickness may be damaged by downsizing of the motor. However, in the fixing method of the present embodiment, since the rotating shaft 3 is caulked by applying a force perpendicular to the thickest shaft fixing surface 5, even if the motor becomes small, cracks or There is no fear of chipping, and the oscillator 4 can be stably fixed.

It should be noted that the present invention is not limited to the above-described embodiment, but can be modified as follows, for example, without departing from the spirit of the present invention.

(1) In the above embodiment, a pair of overhangs 8 are formed in the shaft insertion groove 6 of the vibrator 4 by using the press member 10 having a pair of press pieces 11. The vibrator 4 is formed by using the press member 10 having
A single overhang 8 may be formed in the shaft insertion groove 6. Further, by using a press member 10 having three or more press pieces 11, three or more protrusions 8 are formed in the shaft insertion groove 6 of the vibrator 4.
May be formed. Even in these cases, the rotating shaft 3 can be securely caulked on the inner wall surface of the shaft insertion groove 6.

(2) In the above embodiment, the cross section of the vibrator 4 is a half-moon shape, but may be a rectangular shape, a trapezoidal shape, or the like.

(3) In the above embodiment, the cross section of the press recess 7 has a trapezoidal shape wide on the opening side, but may have a triangular shape, a rectangular shape, or the like.

[0023]

According to the present invention, the following effects can be obtained since the present invention is configured as described above.

That is, by pressing and compressing the vicinity of the shaft insertion groove of the shaft fixing surface with the press piece, the press piece forms a press concave portion and protrudes the inner wall surface of the shaft insertion groove inward. This overhang reduces the width of the shaft insertion groove, and the rotating shaft is sandwiched between the inner wall surfaces of the shaft insertion groove. For this reason, the vibrator is securely fixed to the rotating shaft, and the vibrator does not come off from the rotating shaft even if the motor is downsized. As a result, according to the present invention, a vibration generating motor having excellent durability can be manufactured.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of a vibration generating motor according to the present invention.

FIG. 2 is a sectional view showing a main part of the vibrator of FIG.

FIGS. 3A and 3B are perspective views showing steps of a method for fixing a vibrator according to the present invention.

FIGS. 4 (c) and 4 (d) are perspective views showing steps of a method for fixing a vibrator according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Vibration generating motor, 3 ... Rotating shaft, 4 ... Vibrator, 5 ... Shaft fixing surface, 6 ... Shaft insertion groove, 6a ... Inner wall surface, 7 ... Press recess, 8 ... Overhang, 11 ... Press piece.

Claims (6)

[Claims] 1. A method for eccentrically fixing a block-shaped vibrator having a shaft fixing surface to a rotation shaft of a vibration generating motor, wherein the rotation shaft is inserted into a shaft insertion groove formed along the shaft fixing surface. In this state, the vicinity of the shaft insertion groove on the shaft fixing surface is compressed with a press piece to form a press recess, and the rotary shaft is held by the inner wall surface of the shaft insertion groove that protrudes inward due to the formation of the press recess. And fixing the vibrator to the rotating shaft. 2. The method of fixing a vibrator according to claim 1, wherein the vibrator has a semi-lunar cross section orthogonal to the extending direction of the shaft insertion groove. 3. A vibration generating motor in which a block-shaped vibrator having a shaft fixing surface is eccentrically fixed to a rotating shaft, wherein: a shaft inserting groove formed in the shaft fixing surface for inserting the rotating shaft; A press recess formed by pressing the surface of the shaft insertion groove near the shaft insertion groove with the press piece, and forming a protrusion on the inner wall surface of the shaft insertion groove by compression with the press piece. . 4. The vibration generating motor according to claim 3, wherein a cross section of the vibrator orthogonal to an extending direction of the shaft insertion groove has a half-moon shape. 5. The vibration generating motor according to claim 3, wherein the shaft insertion groove is an R groove or a U groove having substantially the same diameter as the diameter of the rotating shaft. 6. The pressing recess according to claim 3, wherein the pressing recess is formed on both sides of the shaft insertion groove and has a trapezoidal cross section wide on the opening side. Vibration generating motor.