JPH0767266B2 - Vibration actuator for thin information transmission device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a portable device, such as a card type pager, a wristwatch, a mobile phone, or an information transmitting device such as a signal receiver for the blind, by transmitting vibration generated from a vibration actuator to a human body . A thin information transmission that conveys certain information to the wearer of the information transmission device.
The present invention relates to a vibration actuator for a reaching device . Hereinafter, in the present specification, a device that transmits certain information by transmitting vibration to the human body is simply referred to as an “information transmission device”.

[0002]

2. Description of the Related Art An information transmission device using a vibration motor is
Since it is possible to transmit a certain kind of information to surrounding people without causing any inconvenience only by vibration, it has come to be used for pagers, wrist watches, mobile phones, signal receivers for the blind, etc., which are replaced by pagers in recent years. . In the vibration motor in the conventional example, for example, a crescent-shaped weight is attached to the tip of the motor shaft of a cylindrical motor, and the motor is rotated at high speed to obtain vibration. Since it is difficult to make such a cylindrical motor thin as a card-type portable information transmission device, a flat vibration motor has been developed. For example, FIG. 5 is a schematic cross-sectional view of a flat type brushless motor used for an information transmission device in a conventional example. In FIG. 5, a printed wiring board 51 'having a plurality of stator coils 52, for example, three-phase six coils, formed thereon is placed on a stator yoke substrate 51, and a bearing 53 is mounted at the center thereof. There is. In addition, the stator yoke substrate 5
Reference numeral 1 also serves as a motor case made of a magnetic material, and the motor case is omitted in the upper part of the drawing. A shaft 54 is rotatably inserted in the bearing 53. A rotor bush 55 is attached to the shaft 54.
A plate-shaped rotor magnet 57 is fixed via. The rotor magnet 57 is magnetized into a desired number of magnetic poles, for example, 8 poles, and faces the stator coil 52. The flat type brushless motor having such a configuration is
A rotational force is generated in the rotor magnet 57 by a control circuit (not shown) that detects the position of the rotor magnet 57 and sequentially generates a rotating magnetic field in the stator coil 52. When a rotary vibration device is obtained by using the flat type brushless motor as described above, an eccentric weight having a high specific gravity such as tungsten is attached to the rotary shaft of the motor to generate vibration. Further, when a magnetic attraction portion (not shown) is provided on a part of the stator yoke substrate 51 of such a flat brushless motor, the fact that the attraction force of the rotor magnet 57 changes at this magnetic attraction portion is used. Then, vibration is applied to the rotation of the rotor.

FIG. 6 shows a conventional example of a vibration source used for an electric shaver. In FIG. 6, a yoke 61 having a U-shaped cross section has a pair of permanent magnets 62, 62 ′ fixed to its inner surface to form a mover 63. The stator 64 is
The pair of coils 65, 65 'are wound in opposite directions and in a substantially planar shape. Then, the coils 65, 65 '
Are arranged to generate an electromagnetic force by the magnetic fields of the pair of permanent magnets 62, 62 '. A pair of springs 6
6, 66 'are attached to both ends of the mover 63 at one end thereof so as to easily vibrate, and are fixed at the other end together with the stator 64 to a substrate (not shown) by fixing screws 69, 69'. The position detector 67 is arranged in a space in the center of the coils 65 and 65 'and is fixed integrally with the coils 65 and 65'. In addition, the position detector 67 includes the mover 63.
When pressure is applied by the slider 68 provided at the position, the resistance value changes due to this pressure and the positions of the coils 65 and 65 'are detected.

FIG. 7 shows a drive circuit for the vibration source shown in FIG. When the position detector 67 and the slider 68 are located at the position shown in FIG. 6, the position detector 67 is pressed by the slider 68 and exhibits a low resistance value. When the mover 63 moves in the direction indicated by the dotted line or solid line arrow, the position detector 67 is no longer pressed by the slider 68 and exhibits a high resistance value. In the state shown in FIG. 6, the position detector 67 has the slider 68.
It has been pressed by and has a low resistance value. As a result, the base of the transistor 71 becomes L level and flip-flop
The input of the T terminal and the output of the Q terminal of the flop 74 become H level. Further, since the output of the Q'terminal of the flip-flop 74 becomes L level, the output of the AND circuit 75 becomes H level, turning on the transistor 72. Therefore, a current flows through the coil 65. On the other hand, since the output of the Q'terminal of the flip-flop 74 is at the L level, the transistor 73 is turned off and the coil 65 'is turned off.
No current flows through. Then, an electromagnetic force acts on the mover 63 by the current flowing through the coil 65 and the magnetic fields of the permanent magnets 62 and 62 ', and the mover 63 moves in the direction of the dotted arrow in FIG. Due to this force, the slider 68 is disengaged from the position detector 67 and does not press the position detector 67. As a result, the resistance value of the position detector 67 increases, the base potential of the transistor 71 increases, the transistor 71 turns on, and the input of the T terminal of the flip-flop 74 and the input of the AND circuit 75 are set to the L level. To do. Therefore, no current flows through the transistor 72. At this time, the output of the Q'terminal of the flip-flop 74 becomes the H level, the transistor 73 is turned on through the AND circuit 76, and the coil 65 'is turned on.
Apply current to. Since the coils 65 and 65 'are wound in opposite directions, when a current flows through the coil 65', the electromagnetic force acting on the mover 63 by the current flowing through the coil 65 'and the permanent magnet 62 is as described above. In the opposite direction. Therefore, the movement of the slider 68 changes the resistance of the position detector 67, and the transistors 72 and 73 connected to the coils 65 and 65 'are alternately turned on and off, and the coils 65 and 65 are turned on and off. The current flowing to the ‘
Continue the reciprocating motion of.

[0005]

In a vibration source using a cylindrical motor or a flat type motor, a weight having an unbalanced mass attached to its shaft is rotated at a high speed, so that a battery capacity for driving the motor is high. However, it was not possible to make a small and thin vibration source for mobile devices. Further, the above-described motor has a short life because it is worn by a rotating portion such as a shaft due to vibration and rotation, and expensive tungsten or the like is used as a weight, which is an expensive vibration source.
Also, in the above vibration motor, if there is a brush or a commutator,
There is a problem that the sliding noise, the impact noise to the bearing, or the mechanical noise caused by these is large. Furthermore, since the flat type motor that solved some of the above problems was made coreless,
Torque generation efficiency is poor and current consumption is high. Further, in the case of the vibration source as shown in FIG. 6, it is good to obtain a large vibration like an electric razor. However, as a vibration source for simply transmitting information to a person who carries the information transmission device, it consumes a large amount of current and cannot be manufactured in a small size. Further, the vibration source requires a pair of coils, permanent magnets, and springs, and the drive circuit also requires a pair of transistors and AND circuits.
Therefore, it was not possible to obtain an inexpensive vibration source having a simple structure. The rotary vibration part or the reciprocating vibration part in the conventional example has an air gap between the coil and the permanent magnet, and further, an air gap exists between the vibration part provided with the permanent magnet and the case covering the vibration part. . Therefore, there is a limit in reducing the thickness of the vibration source.

The present invention is intended to solve the above problems. For example, the current consumption of a lithium battery (several tens of mA) is sufficient, and the thickness thereof is about the same (2 mm).
An object of the present invention is to provide a vibration actuator for a thin information transmission device having a uniform thickness . Another object of the present invention is to provide a vibration actuator for a thin information transmission device, which has a simple structure and a simple drive circuit.

[0007]

In order to achieve the above object, a vibration actuator for a thin information transmission device of the present invention is a coil composed of a drive coil and a position detection coil that are concentrically wound in a horizontal plane. And the vibration actuator
A movable member made of a printed wiring board provided with a drive circuit, and a spring member made of a supporting member supporting one end of the movable member as a cantilever so that the movable member can reciprocate in the same horizontal plane. , A case that also functions as a back yoke in which permanent magnets are formed so as to face one surface of the coil with a gap, and a case that also functions as a lid member of the case.
And a stator substrate having a stator yoke formed so as to face the other surface of the coil with a gap.

The spring member in the vibration actuator for a thin information transmission device of the present invention is configured to also serve as a lead wire for electrically connecting the coil provided on the printed wiring board and the terminal provided on the spring supporting portion. To be done.

The coil in the vibration actuator for a thin information transmission device of the present invention is configured to be printed on a printed wiring board.

The drive circuit in the vibration actuator for a thin information transmission device of the present invention applies a voltage to the drive coil by a comparator for comparing the voltage applied to the drive coil and the voltage generated in the position detection coil, respectively. And a switch means for turning the voltage on and off.

The reciprocating cycle of the printed wiring board in the vibration actuator for a thin information transmission device of the present invention is configured to be determined by the mass of the printed wiring board and the spring constant of the spring member.

[0012]

[Operation] The drive coil and the position detection coil are, for example, concentrically wound in a horizontal plane and provided on the printed wiring board or formed by printing. Also, the above mark
The printed circuit board has a drive circuit to generate vibration.
It is a mover with attached electronic components. Then, such a mover is supported at one end by a cantilever made of a spring member. Also, the printed wiring board
The spring member is used as a lead wire for the voltage applied to the coil and the electronic component mounted above. That is, the spring member, one of which, the coil on the printed wiring board, the other is connected to a terminal provided on the spring support portion. Case also serving as a back yoke provided with permanent magnets, therein, the coil and electronic components are mounted
After accommodating the printed wiring board and the spring member, etc., the opening of the case is covered with the stator substrate on which the stator yoke is formed. In addition, the stator that serves as the case lid
The board is provided with power supply terminals, wiring patterns, etc.
It At this time, an air gap exists between the coil and the permanent magnet and between the coil and the stator yoke. In such a state, when current flows through the drive coil through the spring member , the current flowing through the coil and the permanent magnet cause
The electromagnetic force is generated in the coil, and the coil etc. are provided.
The printed wiring board as the mover moves in the same plane as the horizontal plane of the printed extension board with the other of the spring members as a fulcrum. Then, after no current flows in the drive coil, it becomes a mover.
The printed wiring board is restored to its original position by the force of the spring member. That is, ON / OF of the current flowing through the drive coil
Due to F, the printed wiring board continuously reciprocates in the same plane as the horizontal plane of the printed wiring board . The cycle of this reciprocating motion is determined by the resonance state due to the mass of the printed wiring board, the coil attached to the printed wiring board, the electronic components of the drive circuit, and the spring constant of the spring member. Spring constant, material and cross-sectional shape of the spring member, for example, cross-section is changed by or a round or square shape. When a current is applied to the drive coil, the printed wiring board moves as described above, the electromotive force generated in the position detection coil decreases, and this voltage is input to the comparator. The voltage applied to the drive coil is fed back to the other input of the comparator.
The output of the comparator at this time works so that the switch provided between the drive coil and the power supply is turned off.
When no current flows through the drive coil, the printed wiring board returns to its original position due to the restoring force of the spring member, and becomes the initial state. This is repeated to make a reciprocating motion. The printed wiring board, while current flows through the coil as described above, print distribution
It receives a force that moves in the same plane as the horizontal plane of the wire plate . Then, when the current no longer flows through the coil, it returns to its original position only by the force of the spring member, so that the current consumption is small and the control circuit is simple. The structure of the vibration actuator is
Since the stator yoke and the back yoke also serve as the case, it is possible to reduce the thickness by the amount of the air gap that has conventionally existed between the case and the vibration actuator. As described above, the vibration actuator for a thin information transmission device of the present invention has a simple structure, consumes enough current to use a lithium battery, and has substantially the same thickness as the lithium battery. In addition, in order to efficiently reciprocate the printed wiring board, the supporting spring member is
Resonance is achieved by appropriately selecting the mass of the spring member and the printed wiring board including the coil and the electronic component , and the material of the spring member and its cross-sectional area.

[0013]

EXAMPLE An example of the present invention will be described with reference to FIGS. FIG. 1 is a perspective view of an embodiment of a case that doubles as a back yoke according to the present invention. FIG. 2 shows an embodiment of a printed wiring board on which the coil of the present invention is mounted. FIG. 3 shows an embodiment of the stator substrate according to the present invention. FIG. 4 is a diagram for explaining an embodiment of the drive circuit for the vibration actuator according to the present invention. In FIG. 1, a permanent magnet 11 is, for example, a neodymium-iron-boron-based permanent magnet, and is formed at a position corresponding to a coil 21 described later on the inner surface of a case 12 made of, for example, iron. Further, since the case 12 is made of iron, it can also serve as a back yoke for the drive coil 22 described later. In FIG. 2, the coil 21 is composed of a drive coil 22 and a position detection coil 23, and is concentrically wound around an air core. The drive coil 22 and the position detection coil 23 may be flush with each other or may overlap each other. In addition, the coil 21 wound in this way
Are embedded in, for example, a groove formed on the printed wiring board 25. Further, the coil 21 can be formed by printing on the printed wiring board 25. Coil 21
When formed by printing, they can be connected to each other by a wiring pattern (not shown) of the printed wiring board 25 without being connected to the drive circuit 41 formed on the printed wiring board 25 by a lead wire. One of the spring members 26 made of, for example, stainless steel or phosphor bronze is attached to one end of the printed wiring board 25, and the other of the spring members 26 is fixed to the spring supporting portion 27. Therefore,
The printed wiring board 25 serves as a mover 20 that can move in the same plane as the printed wiring board 25 with the spring support portion 27 as a fulcrum. Further, the spring member 26 can be used not only for supporting the printed wiring board 25 but also for electrical connection. in this case,
As shown in FIG. 2, the spring member 26 is a set of two terminals, one of which is a terminal 28, 29 formed on the spring support portion 27.
, And the other is connected to the coil 21 via a wiring pattern (not shown). In addition, it goes without saying that the spring member 26 is made of a good electrical conductor when electrically connected. In FIG. 3, the stator substrate 31 is the printed wiring board 25 and the spring member 26.
This is equivalent to a lid that closes the opening side of the case 12 after accommodating the same in the case 12. Stator board 31
A stator yoke 32 made of, for example, iron is formed at a position corresponding to the coil 21. In addition, for example, power supply terminals 33 and 34 are provided at both ends of the stator substrate 31, for example. The connection terminals 37 and 38 on the stator substrate 31 are provided at positions corresponding to the terminals 28 and 29 connected to the spring member 26, and the power supply terminals 33 and 34 and the wiring patterns 35 and 36.
Are electrically connected by. Coil 2 shown in FIG.
1, drive circuit 24, spring member 26, and spring support portion 2
When 7 and the like are accommodated in the case 12 and the opening of the case 12 is closed by the stator substrate 31, there is a slight air gap between the permanent magnet 11 and the stator yoke 32 facing the coil 21. Therefore, the printed wiring board 25
Can move in the case 12 in the direction of the white arrow shown in FIG. 2 with the spring support portion 27 as a fulcrum.

Next, the drive circuit 41 of the vibration actuator will be described with reference to FIG. In FIG. 4, the drive circuit 41 includes a drive coil 22 that gives vibration to the mover 20,
The position detecting coil 23 that detects the position of the mover 20, the transistor 43 that connects the power source 42, for example, a lithium battery to the drive coil 22, and the electromotive force generated in the position detecting coil 23 are used as one terminal for the drive coil 22. Is input to the other terminal via the feedback resistor Rf and the resistor Ra, for example, a comparator 4 including a differential amplifier.
4 and the output of the comparator 44 from the transistor 43
It is composed of a base resistance Rb added to the base and a power switch 45 for supplying a current to the drive coil 22. When the power 42 is turned on by the power switch 45,
The current flows through the drive coil 22. The mover 2 is driven by the current flowing through the drive coil 22 and the magnetic field generated by the permanent magnet 11.
An electromagnetic force acts on 0, and the mover 20 moves in the same plane with the spring support portion 27 as a fulcrum. When the mover 20 moves, the relative position between the coil 21 formed on the mover 20 and the permanent magnet 11 is displaced. Therefore, the electromotive force generated in the position detection coil 23 decreases, and this voltage is input to one terminal of the comparator 44. As for the voltage input to the other terminal of the comparator 44, the voltage applied to the drive coil 22 is fed back by the feedback resistor Rf. The output voltage of the comparator 44 at this time works so that the transistor 43 between the drive coil 22 and the power supply 42 is turned off. As a result, when no current flows through the drive coil 22, the coil 21 returns to its original position due to the restoring force of the spring member 26, and becomes the initial state. A reciprocating motion is performed by repeating this.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments. And
Various design changes can be made without departing from the present invention described in the claims. For example, the shape of the spring member may be any shape other than that shown in FIG. 2 as long as it can change its cross section and can move in the same plane direction as the coil. Further, as the material of the spring member and the permanent magnet, any material other than those described in the embodiments can be adopted. Similarly, the drive circuit is not limited to the embodiment, and can be replaced with circuit components having equivalent functions.

[0016]

According to the present invention , the printed wiring which is the mover.
Since there is no mechanical friction part between the plate and the permanent magnet and the stator yoke, and the mechanical loss is only the spring member,
A vibration actuator for a thin information transmission device having a simple structure, low noise, and long life can be provided. According to the present invention, an electric current is applied only when the mover moves in one direction of the reciprocating motion , and when the mover is restored, the force of the spring member that also serves as a lead wire is used,
Since the mover and its drive circuit are simple, current consumption
To enable the use of lithium batteries
did it. According to the present invention, a coil, a drive circuit, etc. are mounted.
Since the printed wiring board itself placed is a mover,
No special oscillator is required. According to the present invention, the coil is wound on an air core in the same water plane, cable
Is the back yoke, the stator yoke, and the wiring pattern.
Since also serves as the door, lithium thickness of the vibration actuator
It can be manufactured as thin as a lithium battery . Also, this
With such a configuration, since there is no iron loss and magnetic attraction for restraining the permanent magnet, the spring pressure of the spring member can be small, so
It saves current and current. According to the present invention, print coils on a printed circuit board, or the coil using a wiring pattern of the printed wiring board, the drive circuit, connected to the spring member, or the connection terminal and allowing the connection of such feed terminal Because I did
Since it is not necessary to use a lead wire, it is easy to manufacture a vibration actuator for thin information transmission devices and has a long service life against vibration.
Has the effect of extending.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of a case that doubles as a back yoke according to the present invention.

FIG. 2 shows an embodiment of a printed wiring board on which a coil according to the present invention is mounted.

FIG. 3 shows an embodiment of a stator substrate according to the present invention.

FIG. 4 is a diagram illustrating an example of a drive circuit for a vibration actuator according to the present invention.

FIG. 5 is a schematic cross-sectional view of a flat brushless motor used for an information transmission device in a conventional example.

FIG. 6 shows a conventional example of a vibration source used for an electric shaver.

7 is a drive circuit of the vibration source shown in FIG.

[Explanation of symbols]

 Reference Signs List 11 permanent magnet 12 case (back yoke) 20 mover 21 coil 22 drive coil 23 position detection coil 24 drive circuit 25 printed wiring board 26 spring member 27 spring support portion 28, 29 terminal 31 stator substrate 32 stator yoke 33, 34 power supply terminal 35, 36 Wiring pattern 37, 38 Connection terminal 41 Drive circuit 42 Power supply 43 Transistor 44 Comparator 45 Power switch

Claims (5)

[Claims] 1. A mover 20 comprising a coil 21 composed of a drive coil 22 and a position detection coil 23 wound concentrically in a horizontal plane, and a printed wiring board 25 provided with a vibration actuator drive circuit 24. When, the supporting member the movable member 20 is for supporting a cantilever one end thereof for perform a reciprocating motion in the same horizontal plane
A spring member 26 consisting of a case 12 which also serves as a back yoke disposed permanent magnet 11 which is formed so as to face each other with a gap on one side of the coil 21, together with serving as a lid member of the case 12, the coil 2
1. A vibration actuator for a thin information transmission device , comprising: a stator substrate 31 having a stator yoke 32 arranged on the other surface thereof so as to face each other with a gap. 2. The printed wiring board 2 is provided with the spring member 26.
Claims, characterized in that also serves as a lead wire for electrically connecting the terminals 28, 29 provided on the coil 21 and the spring support portion 27 provided on 5 1 thin signaling instrumentation according
Vibration actuator for location. Wherein the coil 21 is a flat-screen information according to claim 1, characterized in that it is printed on the printed wiring board 25
Vibration actuator for information transmission device . 4. A comparator 44 for respectively comparing a voltage applied to the drive coil 22 and a voltage generated in the position detection coil 23, and a switch means for turning on / off the voltage applied to the drive coil 22 by the output of the comparator 44. 43, a thin information transmission device for vibration actuator according to claim 1, further comprising a driving circuit 41 of the printed wiring board 25 made of. Wherein the period of the mover 20 reciprocates, the
The mass of the printed wiring board 25 to the coil and the driving circuit is mounted, according to claim 1, characterized in that it is determined by the <br/> spring constant by the material and cross-sectional shape of the spring member 26 Vibration actuator for thin information transmission devices .