JP2001347224A - Oscillation generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive oscillation generator capable of generating a high oscillating force. SOLUTION: This oscillation generator 1 has an oscillation generating part 2 consisting of a spring member 11, a permanent magnet and an electromagnetic coil 12 and generates an oscillating force by driving the electromagnetic coil 12. In addition the oscillation generator 1 has an oscillation circuit 5 for driving the coil 12, a sensor 3 for detecting the oscillation of the oscillation generating part 2 and a delay circuit 4 for delaying the phase of an output from the sensor 3 almost 90 deg.. Further, the device 1 is equipped with a drive control part 10 which shifts the oscillation frequency of the oscillation circuit 5 to a mechanical resonance frequency by an output from the delay circuit 4. Consequently, it is possible to automatically correct a deviation at a resonance point due to a manufacturing variability, a change with time, a change of external environments and the like and thus always efficiently secure a high oscillating force.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration generator suitable for use in portable telephones, pagers, game machines, and the like.

[0002]

2. Description of the Related Art As a vibration generator of this kind, a structure is used in which an eccentric load made of a metal having a high specific gravity is attached to the output shaft of a small motor, and the center of gravity moves by rotation of the motor to generate vibration. Is widely known for use in mobile phones, game machines and the like.

When such a vibration generating device is incorporated in a mobile phone or a pager (pager (registered trademark)), vibration is generated instead of a ringing tone, so that the vibration generating device can be transmitted to other people, for example, in a crowd or during a meeting. The reception can be confirmed without being known, and in the game machine, by incorporating the vibration generating device in an operation unit or the like, for example, in a car racing game or a fighting game, the operation can be appropriately performed according to the scene. By vibrating the unit, a sense of realism can be given to the operator. Therefore, in order to make such a vibration notification function more remarkable, it is necessary to generate high-amplitude and high-energy vibrations, and the demand for such high-efficiency vibration generators is increasing.

[0004]

By the way, in the above-mentioned motor type vibration generator, it is necessary to increase the eccentric weight of the eccentric load and the operating capacity in order to obtain high amplitude and high energy vibration. This has led to an increase in size and cost, which has been an obstacle to miniaturization and price reduction of devices in recent years.

Further, since the vibration generator uses a DC motor exclusively as a driving source, electromagnetic noise is generated from the rectifying brush when the motor is driven, which has a disadvantage that peripheral circuits are adversely affected. The problem is how to suppress electromagnetic noise. On the other hand, there has been proposed a vibration generating device that generates less noise by vibrating a permanent magnet floating and fixed by a spring member by the attraction of an electromagnetic coil without using such a motor.

[0006] This method is mainly used for a pager (pager) or the like because the structure is relatively simple and the cost can be reduced. If the electromagnetic coil is not driven at the resonance frequency determined by the elastic strength of the vibration generator, it is difficult to efficiently obtain a large vibration force. Since Q also increases, at present, there is no suitable drive method that can always follow the mechanical resonance point, and the deviation of the resonance point due to manufacturing variations, aging, or external environmental changes is corrected. Since there is no way to do so, it has not yet been put to practical use.

The present invention has been made in view of the above-mentioned problems of the conventional vibration generator, and has a high vibration efficiency by making the drive frequency of the electromagnetic coil follow the mechanical resonance frequency of the vibration generation section. It is an object of the present invention to provide an inexpensive vibration generator capable of obtaining a force.

[0008]

According to a first aspect of the present invention, there is provided a vibration generator comprising a vibration member (2) comprising a spring member (11), a permanent magnet (13), and an electromagnetic coil (12). An oscillation circuit (5) for driving the electromagnetic coil (12) in the vibration generator (1) having a vibration force by driving the electromagnetic coil (12).
A sensor (3) for detecting the vibration of the vibration generator (2), and a delay circuit (4) for delaying the phase of the sensor output by approximately 90 °. A drive control unit (10) for shifting an oscillation frequency of the oscillation circuit (5) to a resonance frequency of the vibration generation unit (2) by an output
It is characterized by having.

When the electromagnetic coil is driven by a square wave current,
Focusing on the fact that the signal obtained by the sensor is approximately 90 ° ahead of the drive current at the time of resonance, firstly, it is driven near the resonance point to generate a slight vibration. The oscillation frequency is shifted to the resonance frequency by inputting to the oscillation circuit with a delay of approximately 90 °.
As a result, the deviation of the resonance point of the mechanical system due to manufacturing variations, aging, or external environmental changes is automatically corrected, and a large vibration force can always be obtained efficiently.

[0010] The vibration generator according to claim 2 is
The vibration generating section (2) is composed of a permanent magnet (13) and an electromagnetic coil (12) which are arranged to face each other with a predetermined gap through a U-shaped leaf spring (11) having one end fixed. It is characterized by that.

Since the resonance frequency can be lowered by making the leaf spring U-shaped and increasing the substantial length of the oscillating portion, the shift control to the resonance point by the drive control unit becomes relatively easy.

Further, the vibration generating device according to claim 3 is
The oscillation circuit (5) includes a gate circuit (U1) and a resistor (R3) for connecting an output and an input of the gate circuit (U1).
And a capacitor (C
2).

In this configuration, since control that always follows the resonance point can be realized with a simple circuit configuration, an inexpensive and efficient vibration generator can be realized.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a vibration generator according to the present invention will be described below with reference to FIGS.

FIG. 1 is a diagram showing a circuit configuration of a vibration generating device according to the present invention, FIG. 2 is a diagram showing a schematic configuration of a vibration generating unit, and FIG. 3 is a diagram showing waveforms of various parts of a drive control unit.

The vibration generator 1 according to this embodiment includes a vibration generator 2 having a spring member 11, a permanent magnet 13, and an electromagnetic coil 12, and a drive controller for driving the electromagnetic coil 12 at a mechanical resonance point. 10.

Here, as shown in FIG. 2, the vibration generating section 2 uses a leaf spring in which an elastic long plate is processed into a U-shape as a spring member 11, and the lower end of the U-shaped leaf spring 11 is permanently attached. A magnet 13 is mounted, and an exciting coil 12 is floatingly fixed to the other end of the leaf spring 11 so as to face the permanent magnet 13 with a predetermined gap. The part has a structure fixed to the vibrated body.
In the above configuration, the permanent magnet 13 and the exciting coil 12 may be arranged upside down so that the permanent magnet 13 is float-fixed to the end of the leaf spring 11.

In this embodiment, a weight (pendulum) 14 for efficiently converting the exciting current into vibration energy is attached to the tip of the leaf spring 11 adjacent to the exciting coil 12. The sensor 3 for detecting the vibration of the swing portion is disposed very close to the swing portion inside the U-shape. Since this sensor 3 detects, for example, a slight vibration with an amplitude of about 1 mm, it has a simple structure using a highly conductive iron piece or the like as a detection contact without using commercially available switches. Is also good.

Next, the circuit configuration and operation of the drive control unit 10 will be described with reference to FIGS.

In FIG. 1, reference numeral 5 denotes a square wave oscillation circuit, the output of which is connected to the excitation coil 12 of the vibration generator 2 via a driver U2. The oscillation circuit 5 includes a Schmitt trigger type two-input NAND gate circuit U1 and an integration type loop circuit including a resistor R3 and a capacitor C2 connected thereto. Mechanical system (permanent magnet 13, weight 14, electromagnetic coil 12
The time constant is set so as to self-oscillate at a frequency near the resonance frequency determined by the total weight of the plate spring 11 and the elastic strength of the leaf spring 11).

Reference numeral 3 denotes the vibration detection sensor described with reference to FIG. 1. The contact portion thereof is pulled into the printed circuit board and pulled up to the power supply Vcc by the resistor R1. The fixed side A of the leaf spring 11 close to the sensor 3 is pulled down to the ground.

Reference numeral 4 denotes an integration type delay circuit composed of a resistor R2 and a capacitor C1, and a time constant is set so that the phase of the contact signal S0 is delayed by approximately 90 °.

In the above configuration, when power is turned on to the drive control unit 10, first, the oscillation circuit 5 starts operating as shown in FIGS.
Self-excited oscillation occurs at the timing of the following, and the oscillation output is that S3 drives the exciting coil 12 through the driver U2 in a square wave,
The pendulum 14 is vibrated. FIG. 3A shows a swing state of the pendulum 14 at this time.

When the pendulum 14 vibrates, the contacts of the sensor 3 which have been open until then are turned on / off in synchronization with the vibration.
Repeat the operation. In the case of this circuit configuration, the contact signal S0 is
As shown in FIG. 3 (e), when the electromagnetic coil 12 and the permanent magnet 13 are repelled, the electromagnetic coil 12 is turned off (contact open state), and when attracted, it is turned on (contact short-circuit state). Become. FIG. 3 shows waveforms of respective parts when the driving is controlled at the resonance frequency. As is apparent from the drawing, the driving signal S4 and the contact signal S0 have a phase difference of almost 90 °, At the time of closing, in a state where the drive frequency of the electromagnetic coil 12 has not yet shifted to the resonance frequency, although not shown, the phase relationship between the contact signal S0 and the drive signal S4 has shifted, and The vibration is also very slight.

The operation control when the oscillation frequency of the oscillation circuit 5 is higher than the resonance frequency will be described. The contact signal S0 is delayed from the timing shown in FIG. 3, and the delay signal S1 is delayed from the gate input S2. Is input to the gate U1. For this reason, the gate input S2 becomes a signal in which the leading edge of the ON period is delayed, and as a result, the drive current of the exciting coil 12 is delayed by that amount, and the oscillation frequency becomes slower. , And is finally shifted to a position very close to the resonance frequency.

Conversely, when the oscillation frequency is lower than the resonance frequency, the contact signal S0 is earlier than the timing shown in FIG. 3, and the delay signal S1 is input to the gate U1 earlier than the gate input S2. For this reason, the gate output S3 becomes a signal in which the trailing edge of the pulse signal is advanced. As a result, the drive current of the exciting coil 12 is advanced by that amount, and the oscillation frequency is increased. It approaches and finally shifts to an oscillation frequency very close to the resonance frequency.

By the operation of the drive control unit 10 described above, the vibration generator 1 automatically corrects the deviation of the resonance point of the mechanical system due to manufacturing variations, aging, or external environmental changes. Since driving is always performed near the resonance point, a large vibration force can be obtained efficiently. Further, since the present drive control unit 10 does not employ a complicated feedback control configuration used in a normal correction control system, the circuit configuration is extremely simple, and therefore, it is possible to realize an inexpensive and high-vibration vibration generator 1. Becomes

[0028]

As described above, in the vibration generating device according to the first aspect, the oscillation circuit for driving the electromagnetic coil, the sensor for detecting the vibration of the vibration generating unit, and the phase of the sensor output are substantially changed. A delay circuit for delaying by 90 °, and the oscillation frequency of the oscillation circuit is shifted to the resonance frequency by the output of the delay circuit. The deviation of the resonance point of the system is corrected, and a large vibration force can always be obtained efficiently.

Further, in the vibration generating device according to the second aspect, since the leaf spring is formed in a U-shape, the substantial length of the oscillating portion can be increased even if the vibration generating portion is reduced in size, thereby lowering the resonance frequency. Therefore, the shift control to the resonance frequency by the drive control unit can be performed relatively easily.

Further, in the vibration generator according to the third aspect, since the oscillation circuit is composed of a gate circuit, a resistor and a capacitor, the circuit configuration is extremely simple, and therefore, the vibration generator is inexpensive and efficient. Can be realized.

[Brief description of the drawings]

FIG. 1 is a diagram showing a circuit configuration of a drive control unit according to a vibration generator of the present invention.

FIG. 2 is an external perspective view showing one embodiment of a vibration generating unit of the present invention.

FIG. 3 is a diagram showing waveforms at various parts in a drive control unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vibration generator 2 Vibration generator 3 Sensor 4 Delay circuit 5 Oscillation circuit 10 Drive controller 11 Spring member 12 Electromagnetic coil 13 Permanent magnet U1 Gate circuit R3 Resistor C2 Capacitor

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Minoru Suzuki, Inventor 5-36-11, Shimbashi, Minato-ku, Tokyo F-term in Iwaki Electronics Co., Ltd. 5D107 AA02 AA03 BB08 CC08 CD05 DD03 DD12 DE02 FF08 5H633 BB09 BB10 GG03 GG09 GG17 HH02 JA03

Claims (3)

[Claims] 1. A spring member (11) and a permanent magnet (13).
A vibration generator (1) having a vibration generating unit (2) composed of an electromagnetic coil (12) and an electromagnetic coil (12), wherein the electromagnetic coil (12) is driven to obtain a vibration force. ), A sensor (3) for detecting the vibration of the vibration generator (2), and a delay circuit (4) for delaying the phase of the sensor output by approximately 90 °. A drive control unit (1) that shifts the oscillation frequency of the oscillation circuit (5) to the resonance frequency of the vibration generation unit (2) by the output of the delay circuit (4).
0) A vibration generator comprising: 2. The permanent magnet (13) and the electromagnetic coil (12) disposed opposite each other with a predetermined gap through a U-shaped leaf spring (11) having one end fixed thereto. )
The vibration generator according to claim 1, wherein 3. The oscillating circuit (5) includes a gate circuit (U)
2. The semiconductor device according to claim 1, further comprising a resistor (R3) for connecting the output and the input of the gate circuit (U1), and a capacitor (C2) connected between the input and the ground. The vibration generator according to claim 2.