JPH11230990A - Indicator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an indicator in which a painter can be settled accurately through a simple structure without consuming any power using an oscillatory actuator. SOLUTION: The indicator comprises an oscillatory actuator 7 for driving an oscillator being excited through electromechanical energy conversion and a contactor relatively, an indicating member 6 being driven through the actuator, a resistor means 1 for sensor having resistance variable depending on the state of an object to be detected, a resistor means 8 for detecting position having resistance variable depending on the driving position of the indicating member, and control means 3, 4 for driving the oscillatory actuator in the direction for decreasing the difference of resistance between both resistor means 1, 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device for displaying a state of an object to be detected by a change in electric resistance of a sensor.

[0002]

2. Description of the Related Art As a display device using a sensor having an output proportional to an electric resistance value, there are, for example, a fuel gauge for automobiles and a water temperature gauge. As such a display device, there are a device for displaying a digital numeral and a device for displaying an analog pointer. Among them, the display device for displaying the pointer by analog is favorably used because it has an advantage that the viewer can intuitively recognize the display.

As a driving means of such an analog type display device, a gauge coil, a stepping motor or the like is used.

On the other hand, a vibration type actuator (also referred to as a vibration wave actuator or the like) generally has a phase difference of 90 ° with a piezoelectric element bonded to a vibrating body with a spatial phase difference of 90 °. A traveling wave is generated on the vibrating body by applying the alternating signal of the two phases, and a moving body (contact body) is pressed against the vibrating body to obtain a driving force by a frictional force. A friction material for obtaining an appropriate frictional force is adhered, applied, or formed on a contact portion between the vibrating body and the moving body.

[0005] The characteristics of such a vibration type actuator are that it has a holding torque even when power is not supplied, that it has a large driving torque at low speed compared to an actuator using electromagnetic force, that it has good responsiveness, and that it is audible. The fact that humans do not feel the driving sound because the vibrations above the range are used is quiet. Various applications utilizing such features are expected.

[0006]

For example, in the case of a display device such as a fuel gauge of an automobile, it is preferable that the pointer remains stationary for a long time and that the current position is indicated even when the power is not supplied. For this purpose, the gauge coil and the step motor used in the conventional display device do not have a holding torque when not energized by themselves. there were.

Further, when a friction member or an oil damper is used as a holding mechanism when power is not supplied, the movement becomes unnatural due to hysteresis, and in the case of an oil damper, a seal mechanism for preventing leakage is required. was there.

Further, in the case of these actuators, power is consumed even during stoppage, and the position at which the actuator stops is determined by the position where the frictional force of the friction member or oil damper and the electromagnetic force generated by the coil are balanced. There is a drawback that it is difficult to come out and accuracy is affected by the environment such as temperature.

In view of the above, the present invention relates to a display device for a sensor which outputs an electric signal proportional to the electric resistance value. It is an object of the present invention to provide a display device capable of causing the display device to operate.

[0010]

In order to achieve the above object, according to the present invention, there is provided a vibration type in which vibration is excited by electro-mechanical energy conversion and a contact body which comes into contact with the vibration body is relatively driven. An actuator, a display member driven by the vibration-type actuator, a sensor resistance unit whose resistance value changes according to a state of a detection target, and a position detection resistor whose resistance value changes according to the driving position of the display member And a control means for controlling the driving of the vibration-type actuator in a direction in which the deviation between the resistance value of the resistance means for the sensor and the resistance value of the resistance means for the position detection is reduced.

That is, as a display device for a sensor which outputs an electric signal proportional to the resistance value, a vibration type actuator is used as a drive source of a display member such as a pointer, so that the display member is moved to a display position corresponding to the sensor output. It is possible to achieve a stop that can be stopped with high accuracy and that power consumption during stop can be eliminated, and furthermore, there is little influence of disturbance due to vibration or the like.

Specifically, the control means includes a switching control circuit for outputting a switching pulse signal, and a driving circuit for generating a driving pulse signal to be applied to the vibration type actuator in accordance with the pulse width of the switching pulse signal. The display member can be moved to the display position corresponding to the sensor output as fast as possible by causing the switching control circuit to output a switching pulse signal having a pulse width proportional to the deviation. To do.

In this case, when the deviation is smaller than the predetermined minimum value, the pulse width of the switching pulse signal is set to zero (that is, the vibration type actuator is not driven), and the displayed value changes rapidly. It is desirable to prevent When the deviation is larger than the predetermined maximum value, it is desirable to set the pulse width of the switching pulse signal to a predetermined width so that an excessive current does not flow through the vibration type actuator.

The control means includes a switching control circuit for outputting a switching pulse signal, and a driving circuit for generating a driving pulse signal to be applied to the vibration type actuator in accordance with the switching pulse signal. The switching control circuit may output a switching pulse signal having a frequency lower than the reference frequency at which the driving speed of the vibration type actuator becomes zero by a value proportional to the deviation.

In this case, if the deviation is smaller than a predetermined minimum value, the displayed value changes excessively with the frequency of the switching pulse signal as a reference frequency (ie, without driving the vibration type actuator). It is desirable to prevent At this time, it is desirable to make the pulse width of the switching pulse signal zero to prevent wasteful power consumption. When the deviation is larger than the predetermined maximum value, it is desirable to set the frequency of the switching pulse signal to a predetermined frequency so that an excessive current does not flow through the vibration type actuator.

Further, the control means is provided with a switching control circuit for outputting a switching pulse signal, and a driving circuit for generating a driving pulse signal to be applied to the vibration type actuator in accordance with the pulse width of the switching pulse signal. The switching control circuit may be configured to output a switching pulse signal having a pulse width proportional to the sum of the value proportional to the deviation and the integral value of the deviation.

In this case, when the added value is smaller than the predetermined minimum value, the pulse width of the switching pulse signal is set to zero (that is, the vibration type actuator is not driven), and the displayed value changes excessively. It is desirable to prevent this. When the added value is larger than the predetermined maximum value, it is desirable to set the pulse width of the switching pulse signal to a predetermined width so that an excessive current does not flow through the vibration type actuator.

The control means includes a switching control circuit for outputting a switching pulse signal, and a driving circuit for generating a driving pulse signal to be applied to the vibration type actuator in accordance with the switching pulse signal. A switching pulse signal having a frequency lower than a reference frequency at which the driving speed of the vibration-type actuator becomes zero and a value proportional to the sum of the integrated value of the deviation and a value proportional to the deviation is output to the switching control circuit. You may make it do.

In this case, when the added value is smaller than the predetermined minimum value, the display value changes excessively with the frequency of the switching pulse signal as the reference frequency (ie, without driving the vibration type actuator). It is desirable to prevent this. At this time, it is desirable to make the pulse width of the switching pulse signal zero to prevent wasteful power consumption. When the added value is larger than the predetermined maximum value, it is desirable to set the frequency of the switching pulse signal to a predetermined frequency so that an excessive current does not flow through the vibration type actuator.

The above display device is suitable as a display device for a sensor that detects the amount of engine fuel of an automobile or the like, the temperature of engine cooling water, and the amount of engine lubricating oil.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1 shows the overall configuration of a display device according to a first embodiment of the present invention, FIG. 2 shows an example of the vibration wave actuator in FIG. 1, and FIG. 4 shows an example of the driving circuit of the vibration wave actuator in FIG. 1, FIG. 4 shows an example of the resistance comparison circuit in FIG. 1, and FIG. 5 shows an example of the control flow of the control circuit in FIG.

This display device changes its resistance value according to the state to be detected (the amount of engine fuel, the temperature of engine cooling water, the amount of engine lubricating oil, etc.) and outputs an electric signal proportional to the resistance value. A sensor (sensor resistance means) 1 is provided. In FIG. 1, the amount of engine fuel is indicated by F (FUL
An example of displaying from L) to E (EMPTY) is shown.

A pointer 6 is attached to one end of the output shaft of the vibration wave actuator 7, and the rotation of the vibration wave actuator 7 causes the pointer 6 to rotate on the display panel 5, so that the current value of the sensor 1 is obtained. (Detected value) can be visually recognized.

A movable part of a potentiometer 8 is attached to the other end of the output shaft of the vibration wave actuator 7.

The output (that is, the resistance value) of the sensor 1 is compared with the resistance value of the potentiometer (position detecting resistance means) 8 by the resistance value comparison circuit 2, and a signal (deviation signal) corresponding to the deviation between the two resistance values is obtained. Input to the control circuit 3.

The control circuit (switching control means) 3 generates a drive pulse to be input to the drive circuit 4 based on the deviation signal.

The drive circuit 4 generates a voltage necessary for driving the vibration wave actuator based on the drive pulse. The control circuit 3 and the driving circuit 4 constitute a control means described in the claims.

Here, a specific configuration of the vibration wave actuator 7 will be described with reference to FIG. The vibration wave actuator 7 is pressed against the vibration member 15, the piezoelectric element 16 bonded to the vibration member 15 at a position having a phase difference of 90 ° with respect to the vibration member 15, and the pressure member 14 against the vibration member 15. And a moving element (contact body) 13. Mover 13
Is connected to an output shaft 17 via a pressure spring 14. Further, a friction material having a predetermined friction coefficient different from that of the base material is provided at a contact portion between the vibrating body 15 and the moving element 13.

In the vibration wave actuator 7 thus configured, a traveling wave is generated on the surface of the vibration body 15 by applying a two-phase alternating signal having a phase difference of 90 ° to the piezoelectric element 16. The moving element 13 that is in pressure contact with the vibrating body 15 is rotationally driven by the frictional force. The rotation of the movable element 13 is transmitted to the output shaft 17 via the pressure spring 14, and the movable portion of the pointer 6 and the potentiometer 8 attached to the end of the output shaft 17 are driven.

Since driving of the vibration wave actuator 7 requires a voltage of several hundred volts, the drive circuit 4 in the present embodiment includes one of the transformers (inductance elements) 22, 29 as shown in FIG. DC power supply to the center tap on the next side, MOSFET (switching element) 2 at both ends
1, 25, 28 and 32 are connected respectively, and MOSFET
The transformer 2 is turned on by the ON operations of
A step-up circuit configuration for obtaining a high voltage from the secondary side of 2, 29 is adopted.

When the vibration wave actuator 7 is driven, the MOS connected to both ends of the primary sides of the transformers 22 and 29 are connected.
The control circuit 3 applies a switching pulse signal having an arbitrary pulse width and frequency having a phase difference of 180 ° to the gate of the FET. The phases of the switching pulse signals applied to the gates of the MOSFETs 21 and 25 are 0 ° and 180 °, respectively.
The phases of the switching pulse signals applied to the two gates are 90 ° and 270 °, respectively.

Further, since the transformer has a polarity, for example, a 90 ° switching pulse signal M
A pulse of 270 ° is input to the OSFET, and a pulse of 270 ° is input to the MOSFET to which the switching pulse signal is input.
By inserting a 0 ° pulse, the direction of the current can be changed to reverse the phase relationship between the two phases. Accordingly, the direction of the traveling wave of the vibrating body 15 is reversed, so that the vibration wave actuator 7 can be driven in the reverse direction.

In the circuit shown in FIG.
By changing the pulse width of the switching pulse signal applied to the gate of the transformer, the amount of current flowing into the transformer can be adjusted as shown in FIG. 6, so that the voltage output to the secondary side of the transformer can be changed. Furthermore, since the driving speed of the vibration wave actuator 7 and the applied voltage have a relationship as shown in FIG. 7, the driving speed of the vibration wave actuator 7 can be changed by changing the pulse width of the switching pulse signal.

Here, a specific configuration of the resistance value comparison circuit 2 will be described with reference to FIG. One end of the sensor 1 is grounded, and the other end is connected to a power supply via a variable resistor 9 for adjusting an angle, and is connected to a differential amplifier 10 via a low-pass filter 11.

On the other hand, a movable portion serving as an output take-out portion of the potentiometer 8 connected to the output shaft 17 of the actuator 7 is connected to the differential amplifier 10 via a low-pass filter 12. The differential amplifier 10 has a voltage (deviation signal) proportional to the deviation between the resistance values of the sensor 1 and the potentiometer 8.
Is output.

Next, the operation of the control circuit 3 will be described with reference to FIG. When the output Vin of the resistance value comparison circuit 2 (that is, the deviation between the resistance values of the sensor 1 and the potentiometer 8) is input to the proportional element 33 and the integration element 34 of the control circuit 3, the respective elements 33 and 34 perform predetermined operations. The operation is performed, and both operation results AVin, a∫Vin are added by the adder 35. This output (added value) is Vc.

The control circuit 3 outputs a direction command DIR in a direction to reduce the deviation according to the sign of Vc.

The control circuit 3 determines the magnitude of Vc, an upper limit value (predetermined maximum value) Vmax, and a lower limit value (predetermined minimum value) Vm.
The pulse width command PW is output in accordance with the relationship with "in". Specifically, when | Vc | ≦ Vmin, a command of PW = 0, that is, a pulse width of 0 is issued. Accordingly, when the deviation between the resistance values of the sensor 1 and the potentiometer 8 is smaller than the allowable range as the display device, the vibration wave actuator 7 is not driven, and the display value of the pointer 6 is prevented from being excessively changed. be able to.

When | Vc | ≧ Vmax, a predetermined pulse width PWmax is output.

In other cases, PW is set to | Vc
| Is proportional to |

The DIR, PW and the frequency command f (fixed value) at which the actuator 7 can be driven are input to the four-phase pulse oscillator 36, and a switching pulse signal corresponding to DIR, PW, f is output.

The proportional element 33 and the integrating element 34 are configured as shown in FIGS. 8 and 9 using operational amplifiers 37 and 38, respectively. Diodes 84 and 8 in FIG.
5 is for creating a dead zone. By doing so, hunting of the vibration wave actuator 7 can be prevented.

The drive direction command DIR is determined by referring to FIG.
This is performed using the comparator 39 as shown in FIG. Further, the determination of the pulse width command PW is performed by a circuit shown in FIG. 12 having characteristics as shown in FIG.

Here, reference numerals 40, 44, and 49 in FIG.
Is an operational amplifier, and in particular, the operational amplifier 49 can saturate the output. Reference numerals 41 and 45 denote n diodes connected in series, and the saturation voltage nVf of these diodes 41 and 45 matches Vmin.

A negative voltage is output to the line a in the figure when the input Vc is negative and Vc <-Vmin.

Reference numerals 42 to 44 denote inverting amplifiers each having a gain of 1. Therefore, the input Vc is positive and Vc
When> Vmin, a negative voltage is output.

Reference numerals 46 to 49 denote inverting adders, which add the voltages of the line a and the line b and output the inverted voltage PW. Reference numeral 49 denotes an operational amplifier whose output is saturable, and is adjusted so that the input voltage that saturates becomes Vmax. Thus, the circuit of FIG. 12 can realize the characteristics of FIG.

FIG. 13 shows an example of the four-phase pulse generating circuit 36 shown in FIG. Reference numeral 50 denotes a four-phase sawtooth wave oscillator, which is 0 °, 90 °, 180 °, and 270, respectively.
Generates a four-phase sawtooth wave with a phase of °.

Reference numerals 61 to 64 denote comparators to which a positive input obtained by dividing the pulse width command PW to an appropriate value is input. On the other hand, the output of the four-phase sawtooth wave oscillator 50 is input to the negative input terminal. Thereby, the pulse width command P
The voltage of W is converted to a pulse width.

Numeral 65 denotes a four-input multiplexer which distributes the four-phase pulses in the direction according to the command value according to the value of the direction command DIR.

By inputting the switching pulse signal generated as described above to the drive circuit 4 of FIG. 3, a high voltage can be generated to drive the vibration wave actuator 7.

According to the configuration of this embodiment, when the output value of the sensor 1 changes greatly, the vibration wave actuator 7
Since a large voltage is applied to the actuator and the actuator 7 can be driven at a high speed, the pointer 6 can be quickly moved to the target display position. Further, since the voltage applied to the vibration wave actuator 7 decreases as the pointer 6 approaches the target display position, the pointer 6 can be stopped at the target display position with high accuracy and smoothness.

Further, when stopped, the pulse width of the switching pulse signal becomes 0, and the vibration wave actuator 7
Is not driven, so that no extra power is consumed.

Further, the vibration wave actuator 7 is stopped and held by the friction between the vibrating body 15 and the moving element 13 even when the current is not supplied, so that the indicated value of the pointer 6 does not change due to disturbance such as vibration.

The circuit configuration for carrying out the present invention is not limited to the circuits shown in FIGS. 4, 12, and 13 in the present embodiment. For example, as shown in FIG. 14, an A / D converter and a digital circuit may be used.

In FIG. 14, thick lines represent bus signals.
Reference numeral 74 denotes a clock oscillator having a frequency sufficiently higher than the driving frequency of the vibration wave actuator. The four-phase switching pulse signal is generated by dividing the output of the oscillator 74.

The pulse width command PW of the switching pulse signal is determined by the output of the adder 72 excluding the sign (most significant bit). Also, the direction command DIR
Is determined by the sign (most significant bit) of the adder 72.

In the above embodiment, the case where the pulse width command PW and the direction command DIR are determined according to the magnitude of the added value Vc of the operation result of the proportional element 33 and the integral element 34 has been described. The pulse width command PW and the direction command DIR may be determined according to the magnitude of only the calculation result of 33.

(Second Embodiment) FIG. 15 shows an operation flow of a control circuit (corresponding to the control circuit 3 of the first embodiment) constituting a display device according to a second embodiment of the present invention. FIG. 16 shows the frequency of the vibration wave actuator −
It shows speed characteristics. Note that the basic configuration of the display device of the present embodiment is the same as that shown in FIG. 1 of the first embodiment.

As shown in FIG. 15, when the output Vin of the resistance value comparison circuit 2 (ie, the deviation between the resistance values of the sensor 1 and the potentiometer 8) is input to the proportional element 33 and the integration element 34 of the control circuit 3, respectively. , Each element 33, 34
, A predetermined calculation is performed, and both calculation results AVin, a∫V
in is added by the adder 35. This output (added value) is Vc.

The control circuit 3 outputs a direction command DIR in a direction to reduce the deviation according to the sign of Vc.

The control circuit 3 determines the magnitude of Vc, the upper limit value (predetermined maximum value) Vmax, and the lower limit value (predetermined minimum value) Vm
The frequency command f is output in accordance with the relationship with “in”.

Here, the frequency command f is lower than the reference frequency fs at which the velocity of the vibration wave actuator 7 becomes 0 as shown in FIG. 16 by a frequency Δf determined by the magnitude of Vc as follows. It corresponds to.
Note that the frequency fx shown in FIG. 16 is a frequency at which the vibration wave actuator 7 abnormally vibrates if the frequency is higher than that. In the present embodiment, the vibration wave actuator 7 is set to a frequency fm (higher than the reference frequency fs and the frequency fx). <
fs).

When | Vc | ≦ Vmin, Δf = 0 and a frequency command f corresponding to the reference frequency fs is issued.
Accordingly, when the deviation between the resistance values of the sensor 1 and the potentiometer 8 is small to some extent as an allowable range as the display device, the vibration wave actuator 7 is not driven, and the display value of the pointer 6 is prevented from being excessively changed. be able to.

When | Vc | ≧ Vmax, Δf
= Fs−fm, a frequency command f corresponding to the minimum drive frequency (fm) of the vibration wave actuator 7 is issued. In other cases, Δf is set to a value proportional to | Vc |, and a frequency command f = fs−Δf is issued.

In this embodiment, the circuit for outputting Vc and the circuit for determining Δf can be realized by the same circuits as in FIGS. 4 and 12 shown in the first embodiment.

The DIR, f and the pulse width command PW (fixed value) are input to a four-phase pulse oscillator 66,
A switching pulse signal corresponding to f and PW is output.

Here, the four-phase pulse oscillator 66 can be realized as shown in FIG. Reference numeral 67 denotes a voltage controlled oscillator which outputs a frequency four times the frequency command f according to a command voltage V (f) corresponding to the frequency command f.

Reference numeral 68 denotes a distributor, which comprises a quaternary counter. The divider 68 detects the edge of the output of the voltage controlled oscillator 67 and divides it into four, and outputs 0 °, 90 °, and 18 °.
A four-phase pulse having a phase difference of 0 ° and 270 ° is generated. These pulses are respectively input to four one-shot multivibrators 69, and given a predetermined pulse width.

Further, these four-phase pulses are distributed by the multiplexer 70 in accordance with the direction command DIR.
It is input to the drive circuit 4 shown in FIG.

Also in the present embodiment, when the output value of the sensor 1 changes greatly, a large voltage is applied to the vibration wave actuator 7 and the actuator 7 can be driven at a high speed, so that the pointer 6 is quickly moved to the target display position. Can be done. Further, since the voltage applied to the vibration wave actuator 7 decreases as the pointer 6 approaches the target display position, the pointer 6 can be stopped at the target display position with high accuracy and smoothness.

Further, if the pulse width of the switching pulse signal is set to 0 when the frequency of the switching pulse signal reaches the reference frequency fs and the vibration wave actuator 7 stops, no extra power is consumed. .

Further, the vibration wave actuator 7 is stopped and held by the friction between the vibrating body 15 and the moving element 13 even when the power is not supplied, so that the indicated value of the pointer 6 does not change due to disturbance such as vibration.

The circuit configuration for implementing the present invention is not limited to the circuit shown in FIG. 17 in the present embodiment. For example, in the circuit shown in FIG. 14, a command given from the adder 72 to the frequency dividing circuit 73 may be used instead of a frequency command.

In the above embodiment, the case where the frequency command f and the direction command DIR are determined according to the magnitude of the added value Vc of the operation result of the proportional element 33 and the integral element 34 has been described. The frequency command f and the direction command DIR may be determined according to the magnitude of only the calculation result of.

[0076]

As described above, according to the present invention,
As a display device for a sensor that outputs an electric signal proportional to the resistance value, a vibration type actuator is used as a drive source for a display member such as a pointer, so that the display member can be stopped at a display position corresponding to the sensor output with high accuracy. It is possible to reduce power consumption during stoppage, and further to realize a device that is less affected by disturbance due to vibration or the like.

If the pulse width of the switching pulse signal is set to zero or the frequency is set to the reference frequency when the deviation or the added value is smaller than the predetermined minimum value, the displayed value will not change excessively. Can be prevented. By setting the frequency of the switching pulse signal to the reference frequency and setting the pulse width to zero, useless power consumption can be prevented.

If the pulse width of the switching pulse signal is set to a predetermined width or the frequency is set to a predetermined frequency when the deviation or the added value is larger than a predetermined maximum value, an excessive current is supplied to the vibration type actuator. Can be prevented from flowing.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a basic configuration of a display device according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a configuration of a vibration wave actuator used in the display device.

FIG. 3 is a circuit diagram showing a driving circuit of a vibration wave actuator in the display device.

FIG. 4 is a circuit diagram of a resistance value comparison circuit in the display device.

FIG. 5 is a control flowchart of a control circuit in the display device.

FIG. 6 is a diagram showing a relationship between a pulse width in the drive circuit and a current flowing on the primary side of a transformer.

FIG. 7 is a diagram showing a relationship between an applied voltage and a driving speed of the vibration wave actuator.

FIG. 8 is a configuration diagram of a proportional element constituting the control circuit.

FIG. 9 is a configuration diagram of an integral element constituting the control circuit.

FIG. 10 is a circuit diagram of a portion for determining a driving direction of a vibration wave actuator in the control circuit.

FIG. 11 is an input / output characteristic diagram of a part of the control circuit which determines a pulse width of a switching pulse signal.

FIG. 12 is a circuit diagram of a portion for determining the pulse width.

FIG. 13 is a circuit diagram of a four-phase pulse generation circuit included in the control circuit.

FIG. 14 is a block diagram showing a modification of the first embodiment.

FIG. 15 is a control flowchart of a control circuit in the display device according to the second embodiment of the present invention.

FIG. 16 is a diagram showing a relationship between a driving frequency and a driving speed of the vibration wave actuator.

FIG. 17 is a circuit diagram of a four-phase pulse generation circuit included in the control circuit according to the second embodiment.

[Explanation of symbols]

1. Sensor 2. 2. Resistance value comparison circuit Control circuit 4. Drive circuit 5. Display board 6. Guidelines 7. 7. Vibration wave actuator Potentiometer 9. Volume 10. Differential amplifier 11,12. Low-pass filter 13. Mover 14. Pressing member 15. Stator 16. Piezoelectric element 17. Output shaft 117. DC power supply 18, 84. Capacitors 19, 20, 23, 24, 26, 27, 30, 31, 4
2,43,46,47,48,51,52,53,5
4,55,56,57,58,59,60,81,8
2,83,85. Resistors 21, 25, 28, 32. MOSFET 22, 29. Transformer 33. Proportional element 34. Integral element 35, 72. Adder 36, 66.4-phase pulse generator 37, 38, 39, 40, 44, 49. Operational amplifier 41,45. Diode 50, 86, 87.4 phase sawtooth wave oscillator 61, 62, 63, 64. Comparators 65, 70. Multiplexers 76, 77. AD converter 78. Subtractor 79. Integrator 70, 71. bit shifter 73. Frequency dividing circuit 67. Voltage controlled oscillator 68. Distributor 69. One-shot multivibrator

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Akio Atsuta 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Jun Ito 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inside the corporation

Claims (18)

[Claims] 1. A vibration-type actuator that relatively drives a vibration body whose vibration is excited by electro-mechanical energy conversion and a contact body that comes into contact with the vibration body, a display member driven by the vibration-type actuator, and detection. Sensor resistance means whose resistance value changes according to the state of the object; position detection resistance means whose resistance value changes according to the drive position of the display member; resistance value of the sensor resistance means and the position detection A display device comprising: control means for controlling the driving of the vibration-type actuator in a direction to reduce the deviation from the resistance value of the resistance means for use. A switching control circuit that outputs a switching pulse signal; and a driving circuit that generates a driving pulse signal to be applied to the vibration type actuator in accordance with a pulse width of the switching pulse signal. The display device according to claim 1, wherein the switching control circuit outputs a switching pulse signal having a pulse width proportional to the deviation. 3. The display device according to claim 2, wherein the switching control circuit sets the pulse width of the switching pulse signal to zero when the deviation is smaller than a predetermined minimum value. 4. The display device according to claim 2, wherein the switching control circuit sets the pulse width of the switching pulse signal to a predetermined width when the deviation is larger than a predetermined maximum value. 5. A control circuit comprising: a switching control circuit for outputting a switching pulse signal; and a driving circuit for generating a driving pulse signal to be applied to the vibration type actuator in accordance with the switching pulse signal. Wherein the switching control circuit outputs a switching pulse signal having a frequency lower by a value proportional to the deviation than a reference frequency at which the driving speed of the vibration type actuator becomes zero. The display device according to claim 1. 6. The display device according to claim 5, wherein the switching control circuit sets the frequency of the switching pulse signal to the reference frequency when the deviation is smaller than a predetermined minimum value. 7. The display device according to claim 6, wherein the switching control circuit sets the pulse width of the switching pulse signal to zero when the frequency of the switching pulse signal is set to the reference frequency. . 8. The display according to claim 5, wherein the switching control circuit sets the frequency of the switching pulse signal to a predetermined frequency when the deviation is larger than a predetermined maximum value. apparatus. 9. A switching control circuit for outputting a switching pulse signal, and a driving circuit for generating a driving pulse signal to be applied to the vibration type actuator in accordance with a pulse width of the switching pulse signal. Wherein the switching control circuit outputs a switching pulse signal having a pulse width proportional to an addition value of a value proportional to the deviation and an integrated value of the deviation. The display device according to claim 1. 10. The display device according to claim 9, wherein the switching control circuit sets the pulse width of the switching pulse signal to zero when the sum is smaller than a predetermined minimum value. 11. The display device according to claim 9, wherein the switching control circuit sets the pulse width of the switching pulse signal to a predetermined width when the added value is larger than a predetermined maximum value. . 12. The control means includes a switching control circuit for outputting a switching pulse signal, and a driving circuit for generating a driving pulse signal to be applied to the vibration type actuator in accordance with the switching pulse signal. Wherein the switching control circuit has a frequency lower than a reference frequency at which the drive speed of the vibration-type actuator becomes zero by a value proportional to an addition value of a value proportional to the deviation and an integrated value of the deviation. The display device according to claim 1, wherein the display device outputs a switching pulse signal having the following. 13. The display device according to claim 12, wherein the switching control circuit sets the frequency of a switching pulse signal to the reference frequency when the sum is smaller than a predetermined minimum value. 14. The display device according to claim 13, wherein the switching control circuit sets the pulse width of the switching pulse signal to zero when the frequency of the switching pulse signal is set to the reference frequency. . 15. The switching control circuit according to claim 12, wherein when the sum is larger than a predetermined maximum value, the switching control circuit sets the frequency of the switching pulse signal to a predetermined frequency. Display device. 16. The display device according to claim 1, wherein the detection target is an amount of engine fuel. 17. The display device according to claim 1, wherein the detection target is a temperature of engine cooling water. 18. The display device according to claim 1, wherein the detection target is an amount of an engine lubricating oil.