JPH11150989A - Motor rotation detecting means and small-sized portable device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately judge rotation, non-rotation and the number of revolu tion of a commutator motor. SOLUTION: An apparatus is constituted of a vibration motor 401, a circuit unit 404 which drives the motor 401 and detects its rotation, and a power source for driving them. In this case, the vibration motor 401 itself detects rotation, non-rotation and the number of revolution, by using the current change and the magnetic induction which are generated by changeover of a commutator at the time of rotation. According to the detection results, a driving signal is changed, and display for demanding battery exchange, re-charging, etc., is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotation detecting means and drive control of a small portable device having a commutator type motor having an eccentric weight (hereinafter referred to as a vibration motor).

[0002]

2. Description of the Related Art Conventionally, brush noise generated when a commutator-type motor is rotated adversely affects electronic components, integrated circuits, and the like disposed near the motor, and there is a concern that malfunction may occur. There has been considerable research on how to reduce noise. Therefore, the means of detecting the number of rotations of the motor using the noise and performing feedback control is not presently an example in the related art at present.

As a prior art, a method of detecting the number of rotations of a motor and performing feedback control is disclosed in Japanese Patent Laid-Open No.
7796 and JP-A-5-236775, those based on encoder detection, and JP-A-5-328773 and JP-A-6-
This was due to current detection according to 078594.

In the case of encoder detection, the hardware configuration increases the cost. In the case of current detection, a current detector for detecting the current flowing through the vibration motor or a detected analog current value is converted to a digital value. A circuit component such as an A / D converter for conversion is required, and there has been a problem that a failure rate is increased and reliability is reduced due to an increase in cost and an increase in the number of components.

Further, as disclosed in Japanese Patent Application Laid-Open No. Hei 3-181883, when the voltage of the power supply fluctuates, the voltage value is detected by a circuit, and when the voltage falls below a certain voltage, the driving signal is forcibly stopped. That technology was used.

[0006]

When a vibration motor is rotated, a considerable amount of driving power is required. Therefore, when a small portable device is driven by a button-type battery or the like that can supply only a limited amount of power because its power energy is limited by its volume, it has the following disadvantages.

[0007] Since the impedance of the vibration motor is reduced during driving, a voltage drop of the power supply occurs. Due to this voltage drop, the vibration motor may fall below the operating voltage,
There is a possibility that a malfunction of a vibration motor or a malfunction due to a runaway of a program occurs in an electronic device using a CPU system.

If the vibration motor does not rotate for some reason, the following problem further occurs. When the motor rotates, a counter-induced current is generated in the direction of decreasing the current value.However, in the case of non-rotation, since the counter-induced current does not occur, the current corresponding to the DC resistance of the vibration motor flows as it is and power consumption is significantly reduced. The result is hastening.

Here, the factors controlling the rotation, non-rotation and the number of rotations of the vibration motor include a voltage value, an internal resistance value and a maximum allowable current value on the power supply side, and a coil resistance value on the vibration motor side. There are mechanical loads and the like, and individual differences between the power supply and the vibration motor, temperature environment factors, and so on are various. Therefore, it is very difficult to determine rotation, non-rotation and rotation speed from the voltage value of the power supply. In addition, when judging from the power supply voltage value, it is necessary to set the value with a margin by sufficiently considering the control factors. The possible range was limited to a very limited area and had to be used very wastefully.

As described above, in the case of a small portable device equipped with a vibration motor, it is very important to reliably determine and control its rotation and non-rotation in order to effectively use the limited power supply to the end. Has a significant meaning.

In view of this, it is necessary to directly determine the rotation, non-rotation, and the number of rotations when the vibration motor is driven, not from the indirect parameters such as the voltage value of the power supply, but from the driving of the vibration motor. Was.

Since a vibration motor mounted on a small portable device or the like is very small in size, its brush noise does not adversely affect electronic components, integrated circuits, and the like disposed near the vibration motor. Not at all.

[0013]

In order to solve the above-mentioned problems, a motor rotation detecting means according to the present invention measures the rotation, non-rotation, and the number of rotations of a commutator when the vibration motor itself rotates. Use the current change and magnetic induction generated by switching to ascertain reliably and without complicating the circuit configuration, and change the drive signal depending on the situation, and provide a display that prompts for battery replacement, recharging, etc. Features.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (1) First Embodiment Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. First, a mechanism of generating brush noise will be described.

Is provided. A conductor is wound around the laminated iron core 3 to form a coil. On the other hand, the commutator 4 is electrically connected to the end of the coil wire, and is also electrically connected to the brushes 6 and 7. The field 1 is arranged on the outer periphery with a gap provided with the laminated iron core 3. These are accommodated in the motor case 8 and constitute a vibration motor.

Next, each function will be described.
Functions are largely divided into field and armature. The field creates a constant magnetic field inside the vibration motor, and a permanent magnet is used. On the other hand, the armature is supplied with an electric current from the outside to create a rotating magnet, and here, a drive winding is used.
And since the armature must rotate continuously,
A commutator is added. The function of the commutator is to switch the current supplied through the brush one after another and to rotate it in a fixed direction no matter where the armature is. That is,
The armature is an electromagnet with a changeover switch, and can be said to be a device that continuously generates a rotational force in a fixed direction from any position.

Next, generation of brush noise will be described in detail using a three-slot armature. FIG. 2 schematically shows a cross section of a commutator portion, and shows transition of a rotation state. In FIG. 2A, reference numerals 21, 22, and 23 denote commutators, each of which includes three conductors via an insulating portion 24, and a coil 2.
5, 26 and 27 are electrically connected. Reference numeral 1 denotes a field made of a permanent magnet. Reference numerals 6 and 7 denote brushes, which are electrically connected to one of the conductors of the commutator.

The electric current supplied in the direction a via the brushes 6 and 7 flows in the direction a in each coil, and generates a magnetic pole in the coil as shown in FIG. This magnetic pole and field 1
However, the armature rotates in the direction b. Thereafter, the armature continues to rotate due to the addition of the inertial force, and the state shown in FIG. 2B is changed to the state shown in FIG. 2C.

Referring to FIG. 3, an explanation will be given using an equivalent circuit of brush noise. FIG. 3A shows a connection state between the brushes 6, 7 and the commutators 21, 22, 23 at a certain rotation position. 3
Reference numeral 1 denotes a power supply serving as a current supply source, and coils 25, 26, and 27 are connected to the commutators 21, 22, and 23, respectively.
FIG. 3B shows this state replaced with an equivalent circuit diagram. The coil 27 and the coil 26 are connected in series, and the coil 25 is connected in parallel therewith. Next, FIG. 3C shows a connection diagram in a state where the motor is rotated clockwise by about 60 degrees.
Shown in In FIG. 3A, the commutator 21 is connected to the brush 6, but in the state of FIG. 3C, the commutator 23 is connected. The connection to the brush 7 remains unchanged in that the commutator 22 is connected. FIG.
FIG. 3D shows an equivalent circuit diagram in the state of FIG. Here, when the DC resistance component of each coil is R, the combined resistance value is 2R / 3, and when the voltage of the power supply 31 is E, the steady current value is 3E / 2R. Further, at the time of switching from the state (a) to the state (c), a change occurs in the current distribution of each coil transiently. Even if the steady-state current does not change, a change in the total current occurs at the time of the switching. Specifically, the current in the coil 27 becomes the reverse direction, the current in the coil 26 doubles from E / 2R to E / R, and the current in the coil 25 halves from E / R to E / 2R. When the current polarity of the coil 27 is reversed, a time delay occurs in the inductance component, and a state in which the current value drops momentarily is observed as the total current. This state is shown in FIG. Further, when the current value changes transiently, the leakage magnetic flux to the outside also changes, and it is also possible to convert a change in the magnetic flux into a voltage change using another coil and observe the change. Hereinafter, a transitional change in the current value and a change in the leakage magnetic flux accompanying the switching of the brush are referred to as “brush noise”.

The motor rotation is detected by using the brush noise generated by such a mechanism. FIG. 4 is a plan view of a small portable device according to the present invention, which is a wristwatch that drives a wheel train by a step motor and displays time in an analog manner. Reference numeral 401 denotes a vibration motor, which includes an eccentric weight 402 having a center of gravity at a position eccentric with respect to the rotation shaft 407. Reference numeral 403 denotes a drive coil for a step motor, and 404 denotes a circuit unit, which has a circuit unit for detecting a current change due to brush noise generated when the vibration motor 401 rotates. Further, the circuit unit 404 includes an oscillation circuit using a crystal oscillator, a frequency dividing circuit for dividing the oscillation output thereof,
A driving circuit that outputs driving pulses having different polarities every second based on the frequency division output is included. The drive pulse is output to the drive coil 403. As a result, the stepping motor functioning as a hand driving motor has its driving coil 4
03 is supplied with a drive pulse every second, and the stator 408
Magnetic flux generated through the rotor 410
, And are rotated each time. Reference numeral 406 denotes a power supply for supplying power to the circuit unit 404.

The rotational output of the rotor 410 is
The second hand 411 and the minute hand 41 via the handwheel train mechanism 409
2. The time is transmitted to the hour hand 413, and the time is displayed in an analog manner.

FIG. 5 shows a circuit for detecting rotation / non-rotation, rotation speed or rotation frequency by detecting a change in brush noise current. FIG. 5A is a circuit diagram, and FIG. 5B is a timing chart. The output of the oscillation circuit 501 for generating the reference signal is frequency-divided / decoded by the timing generation circuit 502, and various control signals 521 to 523 are generated. The signal 521 is a signal for rotating the vibration motor 504 and is input to the transistor switch 503. As a result, when the signal 521 becomes high level, the vibration motor 504 is energized and the vibration motor 504 becomes rotatable. A resistor 505 is connected in series with the vibration motor 504 and converts a current waveform into a voltage waveform. The output waveform is 524
Shown in This example shows a case where the vibration motor 504 rotates, and the brush noise waveform is superimposed on the signal 524 as described above. A DC cut filter 506 removes the DC component of the signal 524 and passes only the brush noise component. Reference numeral 507 denotes a voltage comparator having a predetermined detection potential, and is configured so that when the brush noise exceeds a certain level, the output 525 becomes high. A one-shot circuit 508 shapes the waveform of the signal 525 and converts it into a signal 526. Here, the signal 522 is a reset pulse and is output simultaneously with the start of energization of the vibration motor 504. Signal 5
Reference numeral 22 resets the SR flip-flop 509 and the counter 511. If the signal 526 is generated at least once due to the occurrence of the brush noise, the SR flip-flop 509 is set and the signal 527 becomes high. The level of the signal 527 is taken into the flip-flop 510 by the judgment pulse 523 generated after the elapse of a predetermined time.
If the signal 528 is high, it indicates that the vibration motor has rotated. If the rotation cannot be performed, no brush noise occurs and the signal 528 is at a low level. The counter 511 counts the brush noise sequentially after the generation of the reset pulse 522, and can determine the rotation speed based on the counter value 529. Therefore, it is easy to convert the rotation frequency into the rotation frequency from the time when the counter value 529 is taken. It is.

(2) Second Embodiment In this embodiment, the rotation detection of the vibration motor by the brush noise is performed by the drive coil of the step motor of the wristwatch.

Referring again to FIG. Reference numeral 403 denotes a drive coil for a step motor, which also serves as a rotation detection coil of the vibration motor 401. It is desirable to arrange the vibration motor 401 and the drive coil 403 as close as possible in a plane cross section in order to improve the detectability.

FIG. 6 shows a drive waveform and a waveform for detecting the rotation of the vibration motor according to the present embodiment.

Here, reference numeral 61 denotes a drive pulse applied to the drive coil 403, which is output at one second intervals. Reference numeral 62 denotes a drive pulse for driving the vibration motor. This waveform is, for example, 1% DUTY 50%
That is, it is a signal that is repeatedly turned on and off for 0.5 seconds each, and the vibration is generated intermittently, so that it is easy to notify the user. In addition, this driving method allows the power supply 406 itself to rest, as compared with a case where a large current is continuously supplied from the power supply 406, so that the battery life can be extended, and this method is particularly effective in a low temperature environment. It is a driving method.

Here, the rotor 41 of the driving coil 403
The drive pulse 61 applied to the drive coil 403 and the drive pulse 62 applied to the vibration motor 401 are output so as not to be synchronized so that the function of rotating 0 and the function of detecting the rotation of the vibration motor 401 do not overlap. You.

Reference numeral 63 denotes a vibration motor 401 and a rotor 4
10 shows a waveform of the drive coil 403 when the rotor 10 rotates normally, 65 shows a waveform generated by the rotation of the rotor 410, and 66 shows a waveform detected by detecting the brush noise generated by the rotation of the vibration motor 401. Show.

Numeral 64 indicates the waveform of the drive coil 403 when the vibration motor 401 becomes non-rotating for some reason, and only the waveform generated by the rotation of the rotor 410 is generated. The waveform 66 detected by the waveform 63 when the vibration motor rotates does not occur at all, and it is possible to reliably determine whether the vibration motor rotates or not.

FIG. 7 shows an example of a circuit according to the second embodiment. FIG. 7A shows a drive coil 7 for driving a step motor.
FIG. 7B is a circuit diagram in which reference numeral 1 can be used also as a coil for detecting rotation of the vibration motor, and FIG. 7B shows a timing chart thereof. The step motor coil 71 includes PchMOSFETs 72 and 73 and an NchMOSFET7.
4, 75. The drive timing signal is generated by the timing generation circuit 77. In the “a pulse” section in the timing chart of FIG. 7B, the signal 701 (the control signal of the Pch MOSFET 72) and the signal 704 (the control signal of the Nch MOSFET 75) become the on-potential, respectively. Done. One second after that, "b
A pulse "is output, and the signal 702 (PchMOS
FET 73) and signal 703 (NchMOSFET 74)
Becomes the ON potential, and the step motor coil 71 is similarly energized. In this way, the normal clock operation is alternately output as "a pulse" and "b pulse" and driven. Next, as for the output signal of the vibration motor, the drive signal 705 is output by the timing generation circuit 77, and as described above,
This is a 1% DUTY 50% signal. In the timing chart of FIG. 7B, a section “c” corresponds to a driving period of the vibration motor, and is output so as to avoid hand movement pulses “a” and “b”. The signal 701 (P
The channel MOSFET 72) also has the ON potential, and one side of the step motor coil 71 is grounded. In this state, when the brush noise of the vibration motor is generated, the induced potential can be detected at one end of the coil by the magnetic induction. Thereafter, the voltage comparator 76 having a predetermined potential
, A brush noise is detected, and rotation detection and rotation speed detection can be performed by a circuit as shown in FIG. In this way, by controlling the driving signals of the switching elements (72 to 75) connected to the step motor coil 71 as shown in FIG. 7B, it is possible to use the driving signal as a brush noise detection coil. Become.

(3) Third Embodiment The third embodiment is a modification of the second embodiment. This modification is directed to a small portable device having a function of receiving and receiving a magnetic flux generated by an external magnetic field generator for charging by a secondary coil for charging, instead of the stepping motor driving coil of the second embodiment. This is an example using a secondary coil.

In FIG. 8, the charging secondary coil 81 is
By receiving the magnetic flux 83 generated by the magnetic field generator 82, an induced current is generated. This current is supplied to the circuit unit 8
5, the secondary power supply 84 is charged. Vibration motor 86
When the rotation and non-rotation are detected by the secondary coil 81, the difference between the rotation and non-rotation is obvious as in the above-described embodiment, and the determination by the detection circuit unit of the circuit unit 85 is made. Is easy.

It is to be noted that the charging is performed when the user is not carrying. It is not necessary to drive the vibration motor, which is a method of notifying an alarm, by directly applying vibration to the user's skin, and it is not necessary to detect the rotation of the vibration motor. Therefore, the charging secondary coil 81 performs only charging. That is, the two functions of charging and rotation detection of the vibration motor do not overlap.

On the other hand, during non-charging, the charging secondary coil 81
Is only the function of detecting the rotation of the vibration motor, and also in this case, the two functions of charging and rotation detection of the vibration motor do not overlap.

In this embodiment, a wristwatch has been described as an example.
Of course, it is not limited to this. Needless to say, any electronic device may be used as long as there is a component that can be used as a detection coil. In particular, the present invention is effective only in a small size and a space severely restricted.

(4) Fourth Embodiment This embodiment is an example of estimating the degree of deterioration of the power supply using the peak value or the cycle of the rotation detection waveform of the vibration motor detected by the detection member and notifying the user of the deterioration. .

The internal resistance of a lithium button type battery used for general small portable equipment increases remarkably as the discharge proceeds, and it is 10 to 20 times as large as the initial value. This is because when the vibration motor is driven by using the discharged battery, the voltage applied to the vibration motor at the start of driving is a partial voltage of the DC resistance of the vibration motor and the internal resistance of the battery. If the DC resistance and the battery internal resistance are the same, only half of the power supply voltage will be applied.

That is, to determine the degree of deterioration of the battery,
It is important to detect the driving condition of the vibration motor.

In FIG. 9, reference numeral 91 denotes a rotation detection waveform when the deterioration of the power supply is small.

Reference numeral 92 denotes a rotation detection waveform when the power supply deteriorates.

Rotation detection waveform 9 when power supply deterioration is small
1 indicates that a rotation detection waveform 91 that is sufficiently higher than a reference peak value 93 obtained by various characteristics of the power supply and the vibration motor is generated, while the rotation detection waveform 92 of the rotation detection waveform 92 when the power supply deteriorates is set to the reference value. The peak value 93 is smaller than the peak value 93, and the period 94 is also wider. The detection circuit of the circuit unit determines whether the rotation detection waveform is higher or lower than the reference peak value 93, and notifies the user of the deterioration of the power supply. As a specific method, for example, in the case of an analog timepiece, there is a method of changing the hand movement method, and in the case of a portable device equipped with a liquid crystal panel, there is a method of blinking the display.

The user is thereby informed that the battery needs to be replaced in the case of a primary battery and needs to be recharged in the case of a secondary battery. Also, measuring the cycle 94 of the rotation detection waveform has the same effect, and can be used as an index of power supply deterioration.

Next, a circuit for displaying deterioration of the power supply according to the detection result will be described with reference to FIG. FIG. 10A is a circuit block diagram, and FIG. 10B is a timing chart. This embodiment shows an example in which the step motor coil 101 is also used as the detection coil of the vibration motor, as in the embodiment of FIG. The switching elements 102 to 105 are for driving the step motor coil 101,
The timing generation circuit 111 outputs 102S to 102S, respectively.
It is driven by a signal of 105S. Normally, a motor pulse is output every second as shown in FIG.
In (b), the hand is in the first-half second hand movement state. However, in the “c pulse” (signal 111S), if the vibration motor drive signal is output and the motor is not rotating, the hand movement method is changed. Thus, the user can be informed of the power supply deterioration. In this case, the interval between the "a pulse" and the next "a pulse" is set to 2 seconds, the interval between the "a pulse" and the "b pulse" is set to 250 msec. I try not to go crazy. In this example, when a brush noise is detected by the step motor coil 101 at the time of outputting the “c pulse”, the counter 108 passes through the voltage comparator 106 and the waveform shaping circuit 107 as in the example of FIG.
In, the number of rotations is counted. At this time, counting is started after the counter 108 is initialized by the timing generation circuit 111 in advance by the signal 108S. The register 109 holds a predetermined value, and the digital comparator 110 compares the output of the counter 108 with the value of the register 109. Counter 10
If the value of 8 is smaller than the value of the register 109, the signal 110S is set to a high level because the rotation speed of the vibration motor has not reached the predetermined value. The signal 110S is input to the timing generation circuit, and if it is at a high level, the signal 102S
The output cycle of ~ 105S is changed as described above to change the hand movement mode. With the above configuration, it is possible to detect the rotational frequency of the vibration motor and notify the user of the power supply deterioration.

(5) Fifth Embodiment In this embodiment, a more optimal value is obtained by observing the peak value and the period of the rotation detection waveform using the brush noise of the vibration-generating DC motor detected by the detection circuit unit. This is an example of controlling a drive signal of a vibration motor to give vibration to a user.

It is widely known that a vibration motor has a proportional relationship between an applied voltage and a rotation speed, and a rotation speed has a proportional relationship with a vibration amount. That is, when the applied voltage is high, the number of rotations is high, and when the applied voltage is low, the number of rotations is low.

Next, the mechanical stimulation of the skin that receives this vibration will be described. In the living body, in addition to the special sensory organs such as the eyes and ears, receptors (sensory organs) that function to capture signals from the environment inside and outside the body and transmit them to the central nervous system are provided to all tissues of the body Exists. These sensory systems are collectively called the visceral sensation in the body. Among these are receptors that receive mechanical stimuli. The mechanical stimulus here is pressure,
Touch, vibration, and tickling. It is the Pacini body that is the acceleration detector that detects the vibration.
Pacini bodies are relatively large neuronal terminal structures surrounded by subcutaneous adipose tissue and surrounded by connective tissue arranged in layers like an onion. In addition to subcutaneous fat, Pacini bodies are present at various densities in tendons and fascia, on bone marrow, and in joint capsules. When a sinusoidal stimulus is applied to this receptor, an action potential is evoked in each cycle of the sine wave. Although this action potential is transmitted to the central nervous system, the minimum value of the amplitude that elicits one action potential for each cycle of the sinusoidal oscillation depends on the frequency of the oscillation. FIG. 11 shows the relationship between the frequency of vibration (horizontal axis) and the minimum amplitude of vibration (vertical axis) required to induce one action potential per cycle. In other words, it is clear that vibrations of about 100 Hz to about 300 Hz are easy to feel, and when the frequency exceeds 300 Hz, the sensation of the living body becomes dull.

In the present embodiment, the vibration is maintained at an optimum sense frequency of about 100 Hz to about 300 Hz by a change in current generated by switching the commutator when the vibration motor rotates or a cycle of the vibration motor detected by magnetic induction. This is an example of controlling.

Referring to FIG. 12A, a circuit block diagram for keeping the rotation speed of the vibration motor constant by switching the voltage will be described. Reference numeral 121 denotes a power supply, which is a power supply (initial voltage 4) whose output voltage gradually decreases as the remaining capacity decreases.
V, a terminal voltage of 1.4 V). Reference numeral 122 denotes a vibration motor, as shown in FIG. 12B, which is generally known to change the rotation frequency depending on the voltage. In this example, the rotation frequency f is 300 Hz and 1.4 V at 2.2 V.
A description will be given of an example of a vibration motor having such a characteristic that the rotation frequency f becomes 100 Hz. Reference numeral 123 denotes a rotation frequency detection circuit having a circuit configuration similar to that of FIG. 124 is 10
The register holding the comparison value corresponding to 0 Hz is 123
Is compared with the output by the digital comparator 125. Similarly, reference numeral 126 denotes a register holding a comparison value corresponding to 300 Hz, which is compared with the output of 123 by the digital comparator 127. The output signal 125S of the digital comparator 125 has a rotation frequency of 100H.
Low level below z, high level above 100Hz,
The output signal 127S of the digital comparator 127 has a low level when the rotation frequency is less than 300 Hz, and has a high level when the rotation frequency is 300 Hz or more. The DC / DC converter 128 drives the vibration motor 122 with a known voltage converter. Also, DC
The / DC converter 128 can change the voltage conversion ratio by a control signal. For example, when the signal 125S is at a low level, the voltage conversion ratio is increased because the rotation frequency is less than 100 Hz, and when the signal 127S is at a high level, the voltage conversion ratio is decreased. By this control, for example, as shown in the table of FIG.
Even if 21 fluctuates, it is possible to control the voltage conversion ratio to be changed and the voltage applied to the vibration motor 122 to be kept constant. Here, in the present invention, since the rotational frequency of the vibration motor is directly monitored and controlled, the variation in manufacturing, the secular change of the motor characteristics, the impedance change of the power supply 121, and the like cause the fluctuation of FIG. Even if the characteristics change, it is possible to always maintain the optimum frequency. FIG. 13 shows the result of controlling the vibration motor using the circuit described above. It is possible to perform DC conversion according to the power supply voltage and control the frequency of the vibration motor to an optimum frequency. In this example, an example in which the applied voltage is controlled to control the rotation frequency of the motor has been described. And a method of switching the resistance value.

(6) Sixth Embodiment In this embodiment, by observing the rotational state of the vibration motor detected by the configuration as shown in FIG. 5, when the vibration motor is not rotating, the drive to the vibration motor is performed. This is an example in which a signal is switched to supply from a sub power supply to drive a vibration motor.

FIG. 14 is a diagram showing an example of the embodiment. Reference numeral 141 denotes a main power supply, which is usually a power supply for driving the vibration motor 143. Reference numeral 144 denotes a rotation detection circuit similar to that shown in FIG.
The power supply from the main power supply 141 is supplied to the vibration motor 143 by turning on T142. Also,
In the case of non-rotation, 145 s becomes low level and FET 145
Is turned on, and the power of the sub power source 146 is
43. Signals 142s, 1
45s is output from a circuit corresponding to the flip-flop 510 in FIG. 5, is output from the Q output and its inverted XQ output, and is output by the FETs 142 and 145.
It is configured such that either one is turned on.

With such a configuration, even when the voltage of the main power supply 141 drops, the drive is immediately switched to the drive by the sub power supply 146, and the alarm information can be reliably transmitted to the user. Needless to say, it is better to prompt the user to replace the battery in combination with a method of notifying the power supply deterioration as in the example of FIG. The sub power supply 1 used here
The reference numeral 46 is for emergency use until the power supply is replaced, so a small power supply having a smaller capacity than the main power supply 141 may be used.

[0052]

According to the first aspect of the present invention, the rotation, non-rotation, and rotation speed of a commutator type motor mounted on a small portable device are determined from a current change generated by switching of a commutator. It is possible to effectively utilize the limited power supply energy supplied as compared with the above, and to realize more reliable motor rotation control.

According to the second aspect of the present invention, the rotation, non-rotation and the number of rotations of the commutator type motor are detected by a different purpose member to detect a leakage magnetic flux generated by switching of the commutator.
Therefore, the size and weight of the portable device can be reduced without increasing the number of components, and the rotation of the motor can be reliably controlled.

According to the third aspect of the present invention, since the member for detecting the rotation of the motor also serves as the secondary coil for charging provided in the electronic equipment, the rotation of the motor can be reliably controlled without increasing the number of parts. It becomes possible.

According to the fourth aspect of the invention, in the wristwatch for displaying the time in an analog manner, the detecting member also serves as the driving coil of the step motor, so that the number of parts is increased without increasing the number of parts.
Reliable motor rotation control becomes possible.

According to the fifth aspect of the present invention, since the detecting member also serves as a booster coil provided in the electronic device, the rotation of the motor can be reliably controlled without increasing the number of components.

According to the sixth aspect of the present invention, it is possible to easily and easily detect the deterioration of the power supply according to the result of detection of the rotation of the motor, and to notify the user of battery replacement and charging more reliably. It becomes possible.

According to the seventh aspect of the present invention, by controlling the number of rotations in accordance with the result of detection of the rotation of the motor, it is possible to always provide the user with optimal vibration and to use very little energy very efficiently. It can be used.

According to the eighth aspect of the present invention, even if the vibration motor cannot be rotated due to the deterioration of the power supply, the power supply is immediately switched according to the result of the detection of the rotation of the motor, and the alarm time is surely notified to the user. You can let them know.

According to the ninth aspect of the present invention, even when the vibration motor cannot be rotated for some reason in accordance with the result of detection of the rotation of the motor, the user can be reliably notified of the arrival of time by a notification method other than vibration. Can be.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a commutator type motor which is a component of the present invention.

FIG. 2 shows a transition of a rotation state of a commutator portion of the motor of FIG.

FIG. 3 shows an equivalent circuit diagram of the motor of FIG. 1;

FIG. 4 is a plan view of the small portable device according to the first embodiment of the present invention.

FIG. 5 is a circuit diagram and a timing chart for detecting rotation of the motor according to the first embodiment of the present invention.

FIG. 6 is a driving waveform and a waveform detecting rotation of a vibration motor according to a second embodiment of the present invention.

FIG. 7 is a circuit diagram and a timing chart according to a second embodiment of the present invention.

FIG. 8 is a plan view of a small portable device showing a third embodiment of the present invention.

FIG. 9 is a rotation detection waveform according to a fourth embodiment of the present invention.

FIG. 10 is a circuit diagram and a timing chart according to a fourth embodiment of the present invention.

FIG. 11 shows the frequency of vibration (horizontal axis) and the vibration required to induce one action potential per cycle in the fifth embodiment of the present invention. It is a graph which shows the relationship with the minimum amplitude (vertical axis).

FIG. 12 is a circuit block diagram of a fifth embodiment of the present invention, showing a relationship between a power supply voltage and an oscillation frequency and a relationship between a power supply voltage and an applied voltage.

FIG. 13 is a graph showing a state where a vibration frequency is controlled in a fifth embodiment of the present invention.

FIG. 14 is a circuit block diagram according to a sixth embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Field 2 ... Bearing 3 ... Laminated iron core 4 ... Commutator 5 ... Rotating shaft 6, 7 ... Brush 8 ... Motor case 21, 22, 23 ... Commutator 24 ... Insulating part 25, 26, 27 ... Coil 31, 406 .. Power supply 86, 122, 143, 401, 504 Vibration motor 402 Eccentric weight 403 Drive coil 85, 404 Circuit unit 407 Rotating shaft 408 Stator 409 Needle drive train wheel 410 Rotor 411 Second hand 412 ... minute hand 413 ... hour hand 501 ... oscillation circuit 502 ... timing generation circuit 503 ... transistor switch 505 ... resistor 506 ... DC cut filter 507 ... voltage comparator 508 ... one-shot circuit 509 ... SR flip-flop 510 ... flip-flop 511 ... counter 521, 522 , 523, 524, 525, 526,
27, 528, 529 Various control signals 61 Drive pulse for step motor 62 Drive pulse for vibration motor 63 Waveform when vibration motor rotates 64 Waveform when vibration motor does not rotate 65 Rotor rotation waveform 66 Vibration motor Rotation detection waveform 71 Step coil for driving motor 72, 73, 102, 103 Pch MOSFET 74, 75, 104, 105 Nch MOSFET 76 Voltage comparator 77, 111 Timing generation circuit 701, 702, 703, 704, 705 ... Various types Control signal 81 ... Secondary coil for charging 82 ... Magnetic field generator 83 ... Flux 84 ... Secondary power supply 91, 92 ... Rotation detection waveform 93 ... Reference peak value 94 ... Rotation detection waveform period 101 ... Step motor driving coil 106 ... Voltage comparator 107: waveform shaping circuit 108: cow Motor 109 ... register 110 ... digital comparator 102S~105S, 108S, 110S, 111S ...
Various control signals 121 Power supply 122 Vibration motor 123 Rotation frequency detection circuit 124, 126 Register 125, 127 Digital comparator 125S, 127S Various control signals 128 DC / DC converter 141 Main power supply 142, 145 FET 143: vibration motor 144: rotation detection circuit 146: sub power supply 142S, 145S: various control signals

Claims (9)

[Claims] 1. An electronic device comprising a commutator type motor, a circuit unit for driving the motor to detect rotation, and a power supply for driving the motor, wherein when the motor rotates, the commutator is switched. Motor rotation detecting means, wherein a change in the generated current is detected by a detecting circuit. 2. An electronic apparatus comprising: a commutator-type motor, a circuit unit that drives the motor to detect rotation, a power supply that drives the motor, and a detection member that detects rotation of the motor. A motor rotation detecting means, wherein a detection member detects magnetic induction generated by switching of a commutator when the motor rotates. 3. The motor rotation detecting means according to claim 2, wherein the detecting member is a charging secondary coil provided in the electronic device. 4. A motor rotation detecting means according to claim 2, wherein the detecting member is a coil for driving an analog watch provided in the electronic device. 5. The motor rotation detecting means according to claim 2, wherein the detecting member is a booster coil for driving a buzzer or the like provided in the electronic device. 6. A small portable device using the motor rotation detecting means according to claim 1 or 2, and informing a user of deterioration of a power supply according to a rotation detection result. 7. A small portable device using the motor rotation detection means according to claim 1 or 2, wherein a driving method of a commutator type motor is changed according to a rotation detection result. 8. A small portable device using the motor rotation detection means according to claim 1 and switching a power supply according to a rotation detection result. 9. A small-sized portable device using the motor rotation detecting means according to claim 1 or 2, and changing a preset time notification method to a user according to a rotation detection result. machine.