JP4416438B2 - Power supply device - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a power supply device for a DC motor for a vibration generator mainly mounted on a portable device such as a pager.
[0002]
[Prior art]
Many electronic components mounted on portable devices in recent years are surface-mounted, and have been wired to printed wiring boards by reflow soldering.
Note that components that cannot be reflow soldered are conventionally wired by hand soldering or connector type non-soldering. However, in actuality, the manual soldering method has a problem that work efficiency is poor and after maintenance is bad.
[0003]
In addition, the connector type has a problem that the socket part is expensive, the mounting work including the soldering work of the socket part is complicated, and further, the thickness and size cannot be reduced by attaching the socket part. Because of this, recently, a solderless contact method that solves these problems has been widely used.
[0004]
As a solderless contact method, a method using the compressibility of a coil spring is known, and recently it has begun to be used for mounting a flat vibration motor of a vibration generator of a mobile phone device.
In some cases, a conductive compression coil spring inserted into a cylindrical protrusion of a housing is provided between a coil power supply terminal portion of a motor and an electrode provided on a circuit board for electrical connection. (For example, refer to cited document 1)
In order to reduce the thickness, a pair of coil springs inserted through rubber dampers for fixing the motor main body are interposed between the power supply terminal portion of the motor and the electrodes of the circuit board for electrical connection. . (For example, refer to cited document 2)
[0005]
Furthermore, in order to stabilize the electrical contact, a coil spring housed in a resin cylindrical spring guide provided on the bracket of the motor and soldered at one end to the external terminal of the motor is a circuit board. It is surrounded by a part of the insulating elastic body that holds the motor body (see, for example, cited document 3) that is in electrical contact with the electrode, or is fixed to the external terminal of the motor. Some coil springs are electrically connected by being interposed between the power supply terminal portion of the motor and the electrodes of the circuit board. (For example, see cited document 4)
[0006]
[Patent Document 1]
Japanese Utility Model Publication No. 2-141883 [Patent Document 2]
JP-A-8-140301 [Patent Document 3]
Japanese Patent Laid-Open No. 10-117460 [Patent Document 4]
Japanese Patent Laid-Open No. 2002-44907
[Problems to be solved by the invention]
However, the coil spring tends to generate a resonance phenomenon called surging.
In addition, this surging may cause a contact failure of the coil spring or the surface of the electrode, which may cause an electrical contact failure such as peeling of the noble metal plating or movement of the contact point. Furthermore, due to this surging, there is a problem that the life of the coil spring is reduced when it is damaged. In addition, the coil spring may not be able to suppress high-frequency vibration that hinders normal electrical contact.
And from the knowledge of effective use of resources and the miniaturization and thinning of equipment, it was necessary to minimize the size of the insulating elastic body (cushion) that holds the backlash of the motor.
In addition, there is a problem that it is necessary to simplify assembly work such as suspension of soldering work and to increase the versatility of mounted parts to improve production efficiency.
[0008]
Therefore, the present invention solves the above-mentioned problems, particularly secures stable electrical contact and reliability to withstand severe vibrations, and has excellent workability and high versatility as a component. This is to provide a power feeding device.
[0009]
[Means for achieving the object]
As in the invention described in claim 1, the above-mentioned problems are achieved by being sandwiched between a plate-like power supply terminal led out to the side of the motor and an electrode of the circuit board facing the pole of the power supply terminal. A power supply device having elasticity for making an electrical connection, the power supply device accommodating a metal spring corresponding to the number of poles that short-circuit the electrode of the power supply terminal and the electrode of the circuit board, and the spring Insulating elastic member is integrally formed, and the elastic member has the same number of holes as the number of the springs to be accommodated, and the thickness dimension is free of the springs. Shorter than the length and wider than the gap between the power supply terminal and the electrode of the circuit board, and in the clamping, the spring and the elastic member simultaneously press the pole of the power supply terminal and the electrode of the circuit board , The pressing force of the spring is the elastic part Can be achieved also ensuring high reliability to withstand a stable electrical contact with harsh vibration is stronger than the pressing force of the.
[0010]
Furthermore, if the spring is a compression coil spring as in the invention described in claim 2, it can be easily integrally molded with an elastic member having good moldability such as an elastomer.
Further, if the spring is a leaf spring as in the invention described in claim 3, a large number of power feeding devices can be easily formed by continuously molding the spring.
Further, as described in claim 4, by improving at least one side surface of the power feeding device to at least a part of the flat motor, it is possible to achieve improvement in workability and efficiency in parts procurement.
In manufacturing this power supply device, a step of mounting a spring into the molding die out morphism, and a step of compressing the spring, the elastic member in the compressed spring is housed clamping by-mold A plurality of power feeding devices are formed by a step of injecting and forming a power feeding device, and a step in which the formed power feeding device is taken out of the mold and the compressed spring is extended and protrudes from the surface of the elastic member. It can be formed at the same time.
[0011]
[First embodiment]
FIG. 1 is a cross-sectional view of an essential part showing an embodiment of the present invention. The flat motor 10 that generates vibration is placed between the upper housing 20 of the mobile phone device and the circuit board 40 mounted on the lower housing 30 via cushions 61 and 62. In addition, a plate-like power supply terminal 11 that is led out to the side near one end of the motor 10 and faces the other end of the motor 10 is provided, and is further opposed to the pole of the power supply terminal 11. The circuit board 40 is provided with a pair of electrodes 41 for supplying power to the motor 10 by a printed pattern surface. Between the power supply terminal 11 and the electrode 41 formed in this manner, a power supply device 50 whose side surface is partially fixed to the side surface of the motor 10 by an adhesive or a double-sided adhesive member 70 is sandwiched. The electrode 41 and the power supply terminal 11 of the motor 10 are electrically connected to each other. The upper housing is provided with a guide 21 for preventing the motor 10 arranged in an annular shape or similar to the outer diameter of the motor from moving in the radial direction.
[0012]
FIG. 2 is an exploded perspective view showing the configuration of the power supply device 50. In FIG. 2, the power feeding device 50 includes a pair of coil springs 51 and dampers 52 used for compression. The coil spring 51 is formed of a metal wire having a circular or square cross section. On the other hand, the damper 52 is made of synthetic rubber such as natural rubber or urethane rubber as an elastic member, foamed rubber, elastomer having good moldability, or the like. The damper 52 is provided with a pair of vertical holes 52a and 52b. The inner diameters of the holes 52a and 52b are set to the same size as the outer diameter of the coil spring 51 or smaller so that the coil spring 51 can be inserted.
Further, the thickness dimension b of the damper 52 in the direction sandwiched between the power supply terminal 11 and the electrode 41 is larger than the distance a (shown in FIG. 1) between the power supply terminal 11 and the electrode 41, and the free length of the coil spring 51. c is formed larger than the thickness dimension b of the damper 52.
[0013]
The outer shape of the power supply device 50 according to the present invention shown in FIG. 1 and FIG. 2 has a substantially cubic shape. Therefore, a double-sided adhesive tape or the like is attached to the side surface 52c parallel to the penetration direction of the holes 52a and 52b of the damper 52. The adhesive member 70 is affixed and attached to the side surface of the motor 10 where the power supply terminal 11 of the motor 10 is located. This is merely an example, and basically at least a part of the power supply device is electrically connected to the motor body. It may be attached to at least a part of the power feeding terminal.
In addition, when performing this mounting | wearing with an adhesion system, you may use the adhesive agent which has elasticity. The entire coil spring 51 may be plated with noble metal. Further, the damper 52 may be formed of a synthetic resin foam structure to give elasticity and flexibility, or the coil spring 51 may be integrally formed with the damper 52.
[0014]
FIG. 3A is a cross-sectional view showing a state in which the coil spring 51 is inserted into the holes 52 a and 52 b of the damper 52. The outer diameter of the coil spring 51 is set to the same size or slightly smaller than the inner diameter of the holes 52a and 52b. By doing so, since the damper 52 itself has elasticity, the coil spring 51 can be easily inserted into the holes 52a and 52b.
Moreover, after insertion, since the inner surfaces of the holes 52a and 52b hold the outer surface of the coil spring 51, they do not fall off easily. Since the free length of the coil spring 51 is set to be longer than the thickness of the damper 52, the end of the inserted coil spring 51 is exposed from both ends or one side of the damper 52.
[0015]
FIG. 3B shows another example of the end shape of the coil spring 51. The coil spring 51b has its end 51c bent in the coil winding axis direction so that the cut end face faces the power supply terminal 11.
When the cut end surface is brought into contact with the pattern surface of the power supply terminal 11 in this way, reliable conduction is obtained by protruding the pattern surface at the cut end surface.
Further, the end portions 51c are brought close to each other and positioned adjacent to each other. In general, the feeding portion of the motor 10 is small, and the pole interval between the feeding terminals 11 is often very small. Even in such a case, it is necessary to ensure that the end portion contacts the pattern surface. If the end portions 51c are adjacent to each other, the coil springs can be reliably brought into contact with the pattern surfaces of the poles with small intervals.
Since the end 51c can be easily set by rotating the coil spring 51, the end 51c can be adjusted to the power supply terminal pattern surface having various intervals.
Such a configuration in which the end is bent can also be used on the electrode 41 side, so that it is possible to cope with various types of power supply terminals and electrodes by changing only the position setting of the end of the spring.
[0016]
FIG. 4 is a perspective view showing a state in which the power supply device 50 configured as described above is attached to the side surface of the motor 10. The damper 52 is fixed to the side surface of the motor 10 with an adhesive member 70 so that one end of the coil spring 51 is placed on the poles 11 a and 11 b of the power supply terminal 11. Further, the motor 11 to which the power supply device 50 is mounted in this manner is fitted into the guide 21 of the upper housing 20. The guide 21 is provided with a notch 21a facing the electrode 41 of the circuit board 40 shown in FIG. 1, and the power supply terminal 11 of the motor 10 is fitted into the notch 21a without play. In addition, although the guide 21 was shown in the cylindrical shape in FIG. 4, a pillar-like shape matching the outer diameter of the motor may be arranged in an annular shape.
[0017]
FIG. 5 is an essential part cross-sectional view showing the periphery of the power feeding part of the motor 10 in FIG. In FIG. 5, the coil spring 51 is sandwiched between the pole of the power supply terminal 11 and the electrode 41 of the circuit board 40. In other words, the coil spring 51 presses the pole of the power supply terminal 11 and the electrode 41 of the circuit board 40 and short-circuits between the poles to form electrical conduction. Similarly, the damper 52 is sandwiched between the power supply terminal 11 and the electrode 41 of the circuit board 40. In other words, the damper 52 presses the periphery of the contact portion of the coil spring 51 of the electrode 41 of the circuit board 40 with the power supply terminal 11.
[0018]
If the power supply device 50 including the coil spring 51 and the damper 52 is made in a state where the coil spring 51 is inserted through the opening of the damper 52 in advance, it can be immediately attached to the motor when necessary, so that the attachment work can be simplified. Furthermore, there is an advantage that the power feeding device 50 can be used in common even if the motor model is different. Further, by attaching the power supply device 50 to the motor 10 and supplying it, the assembly work can be simplified in the production process of the mobile phone device and the like.
Further, since the damper 52 can select a vibration isolation characteristic different from the cushions 61 and 62 that hold the upper and lower play of the motor 10, the damper 52 can have a further excellent vibration suppression characteristic.
[0019]
FIG. 6 shows the spring characteristics of the coil spring 51 and the damper 52.
In FIG. 6, the X-axis represents the deflection or compression amount, and the Y-axis represents the load or pressing force. Although it can be said from this characteristic diagram, the coil spring 51 is formed of a metal wire and thus has linearity characteristics, and the damper 52 has a rubber spring structure and therefore has non-linearity spring characteristics. The load-deflection characteristic of the spring shown in this characteristic diagram can be replaced with the compression-pressing force characteristic of the spring.
[0020]
In this state, the distance a between the power supply terminal 11 and the electrode 41, the thickness b of the damper 52, the free length c of the coil spring 51, and the length exposed from the damper 52 of the coil spring 51 are as follows. When the length is S1 and the compression amount of the coil spring 51 is S2, the following relationship is established.
S1 = c−b
S2 = ca = S1 + ba
This will be explained with reference to FIG. 6. When the upper housing 20 and the lower housing 30 begin to be combined, the coil spring 51 is first compressed by the amount of S1, and when the S1 is passed, the damper 52 is also compressed at the same time. The amount of S2 is compressed. Thereby, the pressing force of the damper 52 in the compression S2 is P1, and the pressing strength of the coil spring 51 is P2. FIG. 6 shows that P2 is much larger than P1.
This indicates that the damper 52 presses the power supply terminal and the electrode, and the coil spring 51 presses the contact portion with a stronger force.
[0021]
As described above, the pressing force of the coil spring 51 is much stronger than that of the damper 52, and the independent spring function is applied, so that no electrical contact failure occurs. Further, since the damper 52 has a time delay of following the strain to the stress due to the viscoelasticity peculiar to the rubber spring, the insulation effect against the high frequency is remarkably large, and the end portion of the coil spring 51 is in contact with the electrode 41 and the electrode terminal 11. The fine vibration applied to the portion can be absorbed, and the vibration can prevent the wear of the contact surface and the peeling of the plating, thereby maintaining the stable contact.
[0022]
Further, since the coil spring 51 is made of metal, surging is likely to occur due to a resonance phenomenon. However, the holes 52a and 52b of the damper 52 are in contact with the outer diameter of the coil spring 51 from the beginning, and the damper 52 has a volume invariable incompressibility with respect to the deformation unique to the rubber spring. 20 and the circuit board 40 mounted on the lower housing are pressed and pinched so that part of the inner diameter of the holes 52a and 52b is narrowed, and the outer diameter of the coil spring 51 through which the surface is inserted is pushed. Thereby, a part of the vibration given to the coil spring 51 is absorbed or the amplitude of the spring is delayed, so that surging hardly occurs. As a result, there is no breakage even if the contact part is suddenly turned off due to surging or the coil spring 51 is used under severe vibration for a long time.
[0023]
In the power supply device according to the above-described embodiment, a coil spring is attached to an elastic member in which an opening is formed, and the power supply device 50 is made in advance.
In order to manufacture such a power feeding device, a method of simultaneously molding a spring when molding an elastic member by injection molding can be used.
FIG. 7 shows a process of integrally forming a compression coil spring as a power feeding device simultaneously with molding of an elastic member by an elastomer having good moldability.
[0024]
As shown in FIG. 7, the mold used for injection molding includes an upper mold 69 and a lower mold 66.
The lower mold 66 includes a lower mold 64 having a cavity 63 into which an elastomer E forming a damper 62 is injected, and a pin 65 to which a coil spring 61 is attached.
The upper mold 69 is composed of an upper mold 68 having an insertion hole 67 through which the pin 65 is inserted.
The depth of the cavity 63 is set to the height b of the damper 62, and a compression coil spring 61 having a free length c is attached to the pin 65. (Fig. 7 (a))
[0025]
When the upper mold 69 and the lower mold 66 are clamped, the pin 65 is inserted into the insertion hole 67 and the coil spring 61 is compressed to the height b.
When the elastomer E is injected into the cavity 63 in this state, the coil spring 61 is molded integrally with the damper 62 in a compressed state. (Fig. 7 (b))
When the integrally formed damper 62 and coil spring 61 are removed from the mold, the coil spring 61 extends to the free length c. Both ends of the expanded coil spring 61 protrude from the damper 62.
When integrally molded in this way, it is possible to attach to the pin more easily than attaching a spring to the hole of the damper, and it becomes possible to create a large number of power feeding devices at a time by increasing the number of molds taken.
Moreover, since the shape of the cavity can be set relatively freely, it is possible to match the shape of the motor to be mounted.
[0026]
8 and 9 show another embodiment of the power feeding device. The power supply device 80 includes a leaf spring 81 and a damper 82 that use bending. In other configurations, the same components as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof is omitted.
The leaf spring 81 formed in a substantially C shape has an upper portion 81 a in contact with the power supply terminal 11 and a lower portion 81 b in contact with the electrode 41. The free length f of the upper part 81a and the lower part 81b is larger than the distance a between the electrode 41 and the power supply terminal 11, and further larger than the dimension b of the damper 82.
[0027]
In order to form the power supply device 80, as shown in FIG. 9A, the leaf spring 81 is compressed and attached to the lower mold 86 having the cavity 83 set to the width dimension b, and the upper mold 89 is mounted. After the mold is clamped, the elastomer E is injected into the cavity 83.
Thereafter, when the power feeding device 80 is taken out of the mold, the upper portion 81a and the lower portion 81b of the leaf spring 81 are released from the compression and project from the damper 82, and the interval becomes the free length f.
Thus, if a leaf | plate spring is used as a spring, the leaf | plate spring 81 spring can be formed in the continuous state as shown in FIG. A large number of power feeding devices can be easily manufactured by cutting the connecting portion 81c after the continuously formed leaf springs are mounted on the mold.
In each of the above-described embodiments, the power supply terminal 11 or the electrode 41 is paired. However, the number of conduction portions is not limited to this, and a plurality of conduction portions are possible. Further, the arrangement of the springs is not limited to one row, and various arrangements such as a triangular arrangement and a plurality of arrangements in equilibrium are possible.
[0028]
【The invention's effect】
As described above, according to the first aspect of the present invention, there is a surging between the flat power supply terminal led out to the side of the motor and the electrode of the circuit board facing the pole of the power supply terminal. High-frequency vibration can be suppressed, stable electrical contact can be obtained, and highly reliable conduction that can withstand severe vibration can be achieved.
[0029]
Furthermore, according to the structure of Claims 2 thru | or 3, a power feeding apparatus can be formed easily, and according to the structure of Claim 4, the power feeding apparatus can be easily attached to a motor and can be used .
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an essential part showing an embodiment of the present invention.
2 is an exploded perspective view showing a configuration of the power feeding device shown in FIG. 1. FIG.
3 is a cross-sectional view of the power supply apparatus shown in FIG.
FIG. 4 is a perspective view of a motor equipped with a power feeding device according to the present invention.
FIG. 5 is an enlarged cross-sectional view of a main part around the power feeding device shown in FIG. 1;
FIG. 6 is a view showing spring characteristics of a coil spring and a damper according to the present invention.
7 is a diagram illustrating a method for manufacturing the power feeding device illustrated in FIG. 1. FIG.
FIG. 8 is a cross-sectional view of a main part showing another embodiment of the present invention.
9 is a diagram showing a manufacturing method of the power feeding device shown in FIG. 8. FIG.
FIG. 10 is a perspective view of one part used in the power supply apparatus shown in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Motor 11 Feeding terminal 20 Upper housing 21 Guide 30 Lower housing 40 Circuit board 41 Electrode 50 Feeding device 51 Coil spring 52 Damper 61, 62 Cushion 70 Adhesive member

Claims (4)

A power supply device having elasticity that makes them electrically connected by being sandwiched between a plate-shaped power supply terminal led out to the side of the motor and an electrode of a circuit board facing the pole of the power supply terminal,
In this power supply device, a metal spring corresponding to the number of short-circuiting the pole of the power supply terminal and the electrode of the circuit board, and an insulating elastic member that accommodates the spring are integrally formed,
The elastic member is formed with the same number of holes as the number of the springs to be accommodated, and the thickness dimension is shorter than the free length of the spring and wider than the distance between the power supply terminal and the circuit board. ,
In the clamping, the spring and the elastic member simultaneously press the pole of the power supply terminal and the electrode of the circuit board, and the pressing force of the spring is stronger than the pressing force of the elastic member .   The power feeding device according to claim 1, wherein the spring is a compression coil spring.   The power feeding device according to claim 1, wherein the spring is a plate-like spring that utilizes bending. The power feeding device according to claim 1, wherein at least one side surface of the power feeding device is attached to at least a part of the motor .

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