JP2013255384A - Vibration motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low-cost vibration motor which has simple constitution and is reduced in assembly man-hour.SOLUTION: A vibration motor M includes a motor 1 which has an eccentric shaft 2, eccentric with a rotary shaft 1j, fitted to the rotary shaft 1j and also has its outer shell formed of a motor frame 9, and a fall preventive plate 3 which has a plurality of uneven parts 3k each having a projection part 3k2 to be fitted to the motor frame 9 on an upper surface and a recessed part 3k1 on a lower surface. Preferably, the uneven parts 23k of the vibration motor M are formed to be opened outward continuously up to an edge. Preferably, the motor frame 9 and the fall preventive plate 3 are mutually fixed by welding the plurality of uneven parts 3k of the fall preventive plate 3. Preferably, the fall preventive plate 3 is formed by pressing a metal plate.

Description

  The present invention relates to a vibration motor used for mobile communication devices such as mobile phones and PHS, game devices, and the like.

Conventionally, in a mobile communication device, when a call is received, a ringing tone is emitted to notify the carrier, and the vibration caused by the rotation of an eccentric weight (weight) of the vibration motor provided in the portable device can be experienced by the carrier. There are methods for notifying incoming calls, and these can be switched as necessary. In addition, some game devices enhance the entertainment by letting the operator experience the vibration generated by the vibration motor in the device as the game progresses.
This type of vibration motor is fixed in the device, and the generated vibration is transmitted to the housing of the device so that the wearer or the operator can feel the vibration.

  By the way, since the eccentric weight is mounted on the rotating shaft of the vibration motor, the position of the center of gravity is on the eccentric weight side, and when the vibration motor is surface-mounted on the printed circuit board by reflow soldering, It is necessary to devise so as not to shift.

  For example, in Patent Document 1, as shown in FIG. 9, a motor main body is attached to a metal holder frame 130 having tapered protrusions 133 and 134 extending to a side where an eccentric weight 120 fixed to the rotating shaft 111 is located. It is disclosed that surface mounting is performed on a printed circuit board by inserting 110. Since the metal holder frame 130 has the tapered protrusions 133 and 134, the metal holder frame 130 can be prevented from being tilted forward to the eccentric weight 120 side.

  In Patent Document 2, as shown in FIG. 10, in the mounting structure in which the vibration motor 200 having the eccentric weight 202 attached to the rotation shaft of the motor 201 is surface-mounted on the printed board, the side on which the eccentric weight 202 is attached to the rotation shaft. A support plate 203 having an extending portion 203a extending to the surface is provided, the upper surface of the support plate 203 and the lower surface of the frame 205 of the vibration motor 200 are connected by welding, and the lower surface of the support plate 203 and the mounting surface of the printed board are soldered. Connected.

Japanese Patent Laying-Open No. 2009-77521 (FIG. 2) Japanese Patent Laying-Open No. 2011-217489 (FIG. 1)

  By the way, in the method of Patent Document 1, it is necessary to prepare a metal holder frame 130 separately, and man-hours for assembling the metal holder frame 130 with the motor body 110 are required. Further, since the metal holder frame 130 covers the outer periphery of the motor main body 110, the metal holder frame 130 is increased by the thickness of the metal holder frame 130.

  Further, as in Patent Document 2, if the holder is a plate-like support plate 203 and a groove shape (groove portion 203m) is provided between the holder and a printed board (not shown) to be mounted, the size of the motor 201 can be reduced. Each time it changes, a holder support plate 203 that matches the size of the motor 201 must be prepared.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a low-cost vibration motor that has a simple configuration and reduces the number of assembly steps.

In order to achieve the above object, a vibration motor according to a first aspect of the present invention includes a motor in which an eccentric weight eccentric to the rotation shaft is attached to the rotation shaft, and an outer shape is formed by a motor frame, and the motor A collapse prevention plate is provided which has a plurality of concave and convex portions having convex portions attached to the frame on the upper surface and concave portions on the lower surface.
According to the vibration motor of the first aspect, the motor can be attached to the fall prevention plate with a simple configuration.

A vibration motor according to a second aspect is the vibration motor according to the first aspect, wherein the concave-convex portion is formed continuously to the edge and opened outward.
According to the vibration motor of the second aspect, when the fall prevention plate and the substrate are joined by solder, the escape of air or solder is formed by uneven portions, and the fall prevention plate is prevented from being tilted and soldered to the substrate. can do.

The vibration motor according to claim 3 is the vibration motor according to claim 1 or 2, wherein the motor frame and the fall prevention plate are fixed to each other by welding to a plurality of concave and convex portions of the fall prevention plate. .
According to the vibration motor of the third aspect, the motor frame and the fall prevention plate are securely fixed, and welding marks, beads, and the like can be accommodated in the concave portions of the concave and convex portions.

A vibration motor according to a fourth aspect is the vibration motor according to any one of the first to third aspects, wherein the collapse prevention plate is formed by pressing a metal plate.
According to the vibration motor of the fourth aspect, the fall prevention plate can be easily manufactured.

  According to the present invention, it is possible to achieve a low-cost vibration motor that has a simple configuration and reduces the number of assembly steps.

It is a side view of the vibration motor of the embodiment concerning the present invention. It is the perspective view which looked at the vibration motor from diagonally downward. (a) is a side view of the holder, (b) is a plan view of the holder, (c) is a bottom view of the holder, and (d) is a sectional view taken along line AA of (b). It is a top view which shows the land on a printed circuit board. (a) is a side view which shows the holder of a modification, (b) is a top view of a holder, (c) is a bottom view of a holder. It is a sectional side view which shows the mounting state on the printed circuit board of a vibration motor. (a)-(d) is sectional drawing which shows the process of the manufacturing method of a vibration motor. It is a sectional side view which shows a structure in case the motor of the vibration motor of embodiment is a motor with a core. It is an assembly perspective view of the conventional vibration motor of Patent Document 1. It is the perspective view which looked at the vibration motor of conventional patent documents 2 from the upper part.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a side view of a vibration motor according to an embodiment of the present invention. FIG. 2 is a perspective view of the vibration motor viewed from obliquely below.
The vibration motor M of the embodiment is a device that makes the user feel the vibration caused by the rotation of the eccentric weight (weight) 2. The vibration motor M is mounted on the surface of the printed circuit board 7 (see FIG. 6), and is used for portable communication devices, game devices, and the like.

The vibration motor M includes a motor 1 and a holder 3 to which the motor 1 is fixed. The holder 3 to which the motor 1 is fixed is reflow-attached to the surface of the printed board 7.
In the motor 1, the inner rotor and stator are covered with a bottomed cylindrical frame 9 that forms an outer portion of a front portion and an outer peripheral portion. The rear opening 9 a of the frame 9 is closed by a flat resin bracket 8 fixed to the frame 9.

From the rear part of the motor 1, a pair of power supply terminals 4 that are connected to an internal brush 17 (see FIG. 6) and supply current to the armature 11 are exposed to the outside. The power supply terminal 4 has a connection portion 4 s that extends downward along the rear surface of the motor 1 and then bends along the lower surface of the motor 1.
In the motor 1, an eccentric weight 2 that is eccentric with respect to the rotating shaft 1j is fixed to the rotating shaft 1j.

3 (a) is a side view of the holder, FIG. 3 (b) is a plan view of the holder, FIG. 3 (c) is a bottom view of the holder, and FIG. It is AA sectional view taken on the line 3 (b).
The holder 3 has a function of a fall prevention plate that prevents the motor 1 from falling forward due to the eccentric weight 2.
The holder 3 is formed into the following predetermined shape in a flat plate shape by pressing using a steel plate that has been subjected to a plating process that is compatible with solder. As the steel plate, for example, a general rolled steel plate SPCC, a deep drawing rolled steel plate SPCE, or the like is used.

As shown in FIG. 3 (b), the holder 3 includes a rectangular central portion 3o, a pair of front extending portions 3m extending from the central portion 3o to the side (front side) where the eccentric weight 2 is disposed, and a central portion. It has the shape of a flat plate in which a rear extending portion 3u extending rearward from 3o is formed.
The pair of front extending portions 3m of the holder 3 prevents the vibration motor M from falling to the eccentric weight 2 side (front side) and enlarges the bonding area of the vibration motor M to the land of the printed circuit board 7 to increase the bonding strength. Will improve. Similarly, the rear extending portion 3u of the holder 3 prevents the vibration motor M from falling backward, and the bonding area of the vibration motor M to the land of the printed circuit board 7 is increased to improve the bonding strength.

In the central portion 3o of the holder 3, a plurality of concavo-convex portions 3k projecting upward from the lower surface to the upper surface are formed by half-cutting. The concavo-convex portion 3 k has a concave portion 3 k 1 on the lower surface 3 s of the holder 3 and a convex portion 3 k 2 on the upper surface 3 u of the holder 3.
The holder 3 is welded to the frame 9 of the motor 1 at the positions of the recesses 3k1 of the four uneven portions 3k, so that the vibration motor M (see FIG. 2) in which the holder 3 is welded to the frame 9 of the motor 1 is obtained.

By adjusting the height of the concavo-convex portion 3k (the height of the convex portion 3k2), the mounting height of the motor 1 can be changed without changing the plate thickness of the holder 3. Further, the welding strength of the motor 1 to the holder 3 can be stabilized.
In addition, by providing the concavo-convex portion 3k, a welding mark (weld bead, weld mark, etc.) for joining the vibrator (vibration motor M) main body and the holder 3 fits in the concave portion 3k1 on the lower surface 3s of the holder 3. The holder 3 does not protrude downward from the lower surface 3s.

FIG. 4 is a plan view showing lands on the printed circuit board.
On the printed board 7 formed of glass epoxy or the like, lands r1, r2, and r3 are provided by etching or the like.
The land r <b> 1 is a land for connecting the lower surface 3 s of the holder 3, and the lands r <b> 2 and r <b> 3 are lands for connecting the connection portions 4 s of the pair of power supply terminals 4 of the motor 1.

The lower surface 3s of the holder 3 of the vibration motor M in FIG. 2 is connected to the land r1 on the printed circuit board 7 by soldering, and the connection portions 4s of the pair of power supply terminals 4 of the motor 1 are soldered to the lands r2 and r3, respectively. Connected.
With this configuration, when the solder is mounted in a reflow device (not shown), the heated air in the reflow device flows into the gaps s1 and s2 between the holder 3 and the connection portion 4s shown in FIG. Is possible. Therefore, the displacement of the motor 1 and the holder 3 constituting the vibration motor M in the mounting surface direction can be reduced.

<Modified Holder 23>
Next, a holder 23 according to a modification will be described.
Fig.5 (a) is a side view which shows the holder of a modification, FIG.5 (b) is a top view of a holder, FIG.5 (c) is a bottom view of a holder.

The holder 23 of the modified example communicates the uneven portion 23k1 to the side surface of the holder 23, that is, continues to the edge and opens outward, and when the vibrator (vibration motor M) is reflow-mounted on the printed circuit board 7, Constitutes the escape of solder.
Accordingly, it is possible to prevent the vibration motor M from being lifted from the printed circuit board 7 and being tilted and soldered with respect to the pattern lands r1, r2, and r3.

<Internal configuration of vibration motor M>
FIG. 6 is a side cross-sectional view showing a mounting state of the vibration motor on the printed board.
The motor 1 of the vibration motor M in FIG. 6 is a coreless motor, that is, a motor that does not have a laminated core and constitutes the amateur 11 with only coils.
The current supplied to the power supply terminal 4 of the motor 1 is supplied to the coil of the amateur 11 through the brush 17 and the commutator 16. A magnet 12 is provided inside the amateur 11 so as to face the amateur 11, and the magnet 12 is fixed to the frame 9.

  The rotating shaft 1j of the motor 1 is fixed to the armature 11, and is supported by the frame 9 via bearing metals 14 and 15 of sintered bearings. For example, a resin bracket 8 is provided at the other end of the frame 9 in the axial direction, and the inside is closed. The power terminal 4 passes through the bracket 8 and is exposed from the rear surface 8u of the bracket 8 to the lower surface 8s. As described above, the lower surface 9s of the frame 9 is fixed to the convex portion 3k2 of the holder 3 by welding.

<Manufacturing and mounting method of vibration motor M>
Next, a manufacturing method of the vibration motor M and a mounting method on the printed board 7 will be described.
7A to 7D are cross-sectional views illustrating the process of the method for manufacturing the vibration motor M.
As shown in FIG. 7 (a), the convex portion 3 k 2 on the upper surface 3 u side of the concave and convex portion 3 k of the holder 3 of the fall prevention plate of the motor 1 is brought into contact with a predetermined position on the lower surface 9 s of the frame 9 of the motor 1. Then, the frame 9 and the holder 3 of the motor 1 are welded and fixed at the positions of the plurality of uneven portions 3 k of the holder 3. In this case, since the portion of the frame 9 that is in contact with the convex portion 3k2 of the holder 3 is a welding location, welding marks, beads, and the like are contained in the concave portion 3k1 of the concave and convex portion 3k on the lower surface 3s of the holder 3.

Subsequently, as shown in FIG. 7B, the bearing metals 14 and 15 and the magnet of the stator are fixed inside the frame 9.
Subsequently, as shown in FIG. 7C, the bracket portion of the armature core assembled in advance, that is, the rotating shaft 1j, the armature 11, the commutator 16, the brush 17, the bracket 8, and the like are attached to the frame 9. Inserted.

Subsequently, as shown in FIG. 7 (d), the eccentric weight 2 is fixed to the rotating shaft 1j by, for example, press-fitting or adhesive, thereby completing the vibration motor M.
Thereafter, the lower surface 3s of the holder 3 of the vibration motor M shown in FIG. 2 is connected to the land r1 (see FIG. 4) on the printed circuit board 7 by soldering, and the connection portion 4s of the power terminal 4 of the motor 1 is printed. The vibration motor M is mounted on the printed circuit board 7 by being connected to the lands r2 and r3 on the circuit board 7 by soldering (see FIG. 6).

FIG. 8 is a side sectional view showing a structure when the motor of the vibration motor of the embodiment is a cored motor.
Next, the case where the motor 20 of the vibration motor 2M is a motor with a core, that is, a motor having a laminated core and having a coil wound around a salient pole will be described.
The current supplied to the power supply terminal 24 is supplied to the amateur 21 through the brush 27 and the commutator 26. The amateur 21 has a core 26. Inside the frame 29, a magnet 22 is fixed to the inner wall of the frame 29 so as to face the core 26.

The rotating shaft 20j of the motor 20 is fixed to the armature 21 and the rotating shaft 20j is supported on the frame 29 via bearing metals 24 and 25. For example, a resin-made bracket 28 is provided at one end of the frame 29 in the axial direction, and the power supply terminal 4 penetrates the bracket 28 and is exposed from the rear surface 28u of the bracket 28 to the lower surface 28s.
As described above, the holder 3 is fixed by welding on the lower surface 29s of the frame 29 and the convex portion 3k2 of the concave-convex portion 3k.

As a manufacturing procedure of the mounting structure of the vibration motor 2M, it is necessary to fix the magnet 22 to the inner wall of the frame 29. For example, the following can be performed.
Before fixing the magnet 22 to the frame 29, first, the convex portion 3k2 of the holder 3 is fixed to the lower surface of the frame 29 by welding. After welding, the magnet 22 is fixed to the inner wall of the frame 29 with an adhesive or the like.

Subsequently, after the bearing metal 24 is attached to the front portion of the frame 29, the bracket portion of the armature core assembled in advance, that is, the rotating shaft 20j, the armature 21, the commutator 26, the brush 27, the bearing metal 25, the bracket 28, and the like. Is inserted into the frame 29.
The vibration motor 2M is completed by attaching the eccentric weight 22o to the rotary shaft 20j by press-fitting or adhesive.

According to the said structure, the metal holder which fixes the main body of the motors 1 and 20 becomes unnecessary, and the man-hour for assembling the main body of the motors 1 and 20 and a metal holder is eliminated.
Further, by providing the concave and convex portion 3k on the holder 3 of the fall prevention plate, a solder fillet is formed at that location, so that the joining strength can be increased and the strength against drop impact is increased.
Furthermore, when the holder 3 is pressed, the amount (number and height) of the concavo-convex portions 3k can be controlled so that it can be attached to the motors 1 and 20 corresponding to the respective sizes. There is no need to prepare.

In the embodiment described above, the uneven portions 3k and 23k are circular and long grooves. However, other shapes may be used as long as the uneven portions described above are provided. However, as described above, it is more preferable that the concavo-convex part is formed continuously to the end edge of the holder 3 and opened outward.
In addition, although the said embodiment demonstrated and demonstrated the motor with a core and a coreless motor, you may apply motors other than these.

In addition, although the holder 3 illustrated the case of plate shape, it does not necessarily need to be plate shape. However, it is more preferable that the holder 3 has a plate shape because it can be easily manufactured.
In the above-described embodiment, various configurations have been described. However, these configurations may be appropriately selected and combined. Thereby, the combined effect is acquired.

  While various embodiments of the present invention have been described above, the description is intended to be exemplary. Accordingly, various modifications and changes can be made within the scope of the present invention. That is, the present invention can be arbitrarily changed as appropriate without departing from the spirit of the invention.

1, 20 Motor 2, 22o Eccentric weight 3 Holder (falling prevention plate)
3k Concavity and convexity 3k1 Concavity 3k2 Convex 9, 29 Frame (motor frame)
1j, 20j Rotating shaft M, 2M Vibration motor

Claims (4)

A motor in which an eccentric weight eccentric with respect to the rotation shaft is attached to the rotation shaft, and an outer shell is formed by a motor frame;
A vibration motor comprising: a falling prevention plate having a plurality of concave and convex portions having convex portions attached to the motor frame on an upper surface and concave portions on a lower surface. The vibration motor according to claim 1, wherein the concavo-convex portion is formed continuously to the edge and opened outward. The vibration motor according to claim 1, wherein the motor frame and the fall prevention plate are fixed to each other by welding to a plurality of uneven portions of the fall prevention plate. The vibration motor according to any one of claims 1 to 3, wherein the fall prevention plate is formed by pressing a metal plate.

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