KR820001104B1 - Displaced position detecting device - Google Patents

Abstract

The device detects a displaced position by generating an ultrasonic signal in a magnetostrictive wire and measuring the propagation time of the signal generated. The device includes an exciting device to generate an ultrasonic signal in a magnetostrictive wire, and receivers to receive the ultrasonic signal generated in the magnetostrictive wire by the exciting device. A device changes the distance between the exciting device and each of the two receivers in accordance with a mechanical displacement. A circuit produces a signal representative to the time periods required for the generated ultrasonic signal to reach two receivers.

Description

Displacement position conversion device

1 is a block diagram showing Embodiment 1 of the present invention.

2 is an operational waveform diagram of the first FIG. Device.

3 to 5 are schematic diagrams showing another embodiment 1 of the present invention.

6 and 7 are configuration diagrams showing an application example of the apparatus of the present invention.

Fig. 8 is a configuration diagram showing an example in which the present invention is applied to a position return means in an automatic balance meter.

9 is an electrical circuit diagram thereof.

10, 11, 13 and 14 are diagrams showing some examples of excitation means used in the apparatus of the present invention.

12 is a principle of operation of FIG.

Fig. 15 is a block diagram showing another embodiment of the present invention.

Fig. 16 is his construction monograph.

17 is an operational waveform diagram thereof.

18 and 20 are connection diagrams showing an example of an arithmetic circuit used in the apparatus of the present invention.

19 is an operational waveform diagram of an apparatus of FIG. 18;

21 is a diagram showing the relationship between the displacement and the output voltage in the circuit of FIG.

Fig. 22 is a block diagram of a case where the apparatus according to the present invention is applied to an automatic balance meter.

The present invention relates to a displacement position converting apparatus for converting a mechanical displacement position into an electrical signal according to a new principle, and using the propagation time of a signal propagating in a magnetostriction line to detect a mechanical displacement position. Relates to a device.

The apparatus according to the present invention is effective when used in the position return means level meter of the automatic balance meter, the differential pressure transmitter and the like.

For example, the displacement position shifting device used as a position return means of an automatic balancing instrument is used for the potentiometer, and the inductance, potentiometer, and program for converting the magnetic unbalance caused by the rotation angle into an electrical signal. Some are used in Lux bridges, displacement magnetic modulators, and the like.

However, the use of the winding type in the potentiometer is regulated in accordance with the number of windings, and the thermoelectric power is generated by frictional heat between the sliding brush and the winding resistor, which appears as noise.

In addition, there are problems such as life due to friction.

Induction potential meters, flux bridges, displacement magnetic modulators, etc. have the advantage that they do not have mechanical contacts, but they are complex and expensive.

An object of the present invention is to realize a displacement position converting device of a simple structure and a low cost.

In addition, another object of the present invention is to realize this kind of device having a high degree of detection without being affected by ambient temperature.

According to a preferred embodiment of the present invention, an excitation means for generating a distortion wave signal in the magnetostriction, first receiving means for receiving an ultrasonic signal generated in the magnetostriction coupled to the magnetostriction, second reception means, excitation means and the first reception means Means for changing the distance between the means and the second receiving means corresponding to the mechanical range, and two relating to the time until the signal generated in the magnetostriction by the excitation means reaches the first receiving means and the second receiving means. A circuit means is provided which uses a signal to obtain a signal corresponding to a mechanical displacement.

FIG. 1 is a block diagram showing an embodiment of the present invention. In the figure, 1 is a magnetostrictive wire composed of a magnetostrictive material such as Ni-SPANC Ni, etc., and supported so that mechanical vibration is not transmitted.

2 is a first receiving means arranged on one edge of the magnetostriction 1, 3 is a second receiving means arranged on the other edge of the magnetostriction 1, and 4 is a first receiving means interposed between the magnetostriction 1s. The excitation reception generates an ultrasonic signal in the magnetostriction 1 disposed between the receiving means and the second receiving means. In this embodiment, any one of the first receiving means, the second receiving means, and the excitation means is shown as an example composed of a coil which can be wound around the magnetostriction line.

5 denotes the overall movement of a movable part given a mechanical displacement and moving in response to the mechanical displacement,

In this embodiment, the excitation means 4 is attached to the movable portion 5.

The OS is an excitation pulse generator, and this output pulse PE is applied to the set terminal S of the flip-flop circuits FF ₁ and FF ₂ described later after being applied to the excitation means 4. have.

OP _1, OP ₂ are Any of a comparison amplifier, OP ₁ is the first to enter a detection signal e ₁ in the receiving means 2, and the detection signal compares the e ₁ and the set voltage Es, and e _1> Es when the The deviation is amplified and applied to the reset terminal R of the flip-flop circuit FF ₁ . In addition, OP ₂ is a second receiving means and to the input of the detection signal e ₂ of 3, compared to the detection signal e ₂ and the set voltage Es and, e _2> and when the Es amplifies the deviation, and the flip-flop circuit FF Apply to reset terminal R of ₂ .

CK is an arithmetic circuit for inputting the time width signals PW ₁ and PW ₂ obtained from the flip-flop circuits FF ₁ and FF ₂ .

The operation of the device configured as described above will be described with reference to FIG. 2 below. First, the excitation pulse PE is first applied to the excitation means 4 as shown in FIG. 2A in the excitation pulse generator OS.

When an excitation pulse is applied to the excitation means 4, a distortion wave signal (ultrasound signal) is generated inside the magnetostriction 1 by the Joule effect, which is transmitted toward both ends of the magnetostriction 1.

This ultrasonic signal finally reaches the first receiving means 2 and the second receiving means 3 provided at both ends of the magnetostriction 1.

In this embodiment, each receiving means is constituted by a coil, and when the ultrasonic signal passes through the magnetostriction ₁ , the voltage signals e ₁ , pulses are transmitted to the receiving means 2 and 3 by the so-called Villari effect. e ₂ occurs as shown in Figs. 2b and 2c.

Now, when the excitation pulse PE is applied to the excitation means 4 and an ultrasonic signal is generated in the magnetostriction 1, the ultrasonic signal propagates in the magnetostriction 1 at the position of the excitation means 4, and then to each of the reception means 2 and 3. The times t ₁ and t ₂ to reach can be expressed by the formulas (1) and (2).

However, vs: speed at which the ultrasonic signal propagates through the magnetostriction 1.

1 ₁ : Excitation means 4 (distance of movable part 5 and first receiving means 2

1 ₂ : distance between aftershock means 4 and second receiving means 3.

Excitation pulse PE is, excitation means 4 is at the same time also the flip-flop circuit FF _1, and are respectively applied to the set terminal S of the FF _2, for each flip-flop circuit FF _1, FF ₂ second 2d are on, display of claim 2e also with Set it together.

In addition, the voltage signals e ₁ and e ₂ of the pulses obtained by the first receiving means 2 and the second receiving means 3 after t ₁ and t ₂ after the excitation pulse PE are supplied are provided with a flip-flop circuit between the comparison amplifiers OP ₁ and OP ₂ . FF _1, applied respectively to the reset terminal of the FF ₂ and, to reset them to the state as shown in the Figure 2c, Figure 2d claim.

Therefore, at the output terminals of the flip-flop circuits FF ₁ and FF ₂ , the time width signals PW ₁ and PW ₂ with time widths t ₁ and t ₂ proportional to 1 ₁ and 1 ₂ as shown in FIGS. 2d and 2e are represented. Obtained.

The calculation circuit CK detects the angle flip-flop circuits FF ₁ , FF _{2, for} example, the time widths t ₁ , t ₂ and calculates the equation (3) so that the signal E _o associated with the excitation means 4, i.e., the displacement position x of the movable part 5, is obtained. Can be obtained from output terminal OUT.

Just x = 1 ₁ -1 ₂

In the formula (3), 1 ₁ + 1 ₂ is the distance between the first receiving means 2 and the second receiving means 3, and is a constant value despite the displacement position x of the movable part 5, so that the output signal E ₀ is It becomes exactly proportional to the displacement position x.

In addition, when the calculation circuit CK is configured by the digital calculation circuit, the output signal E ₀ is easily obtained by the digital signal, or by the analog circuit, the E ₀ is easily obtained by the analog signal.

The signal E ₀ associated with the position x of the true moving part 5 thus obtained is advantageously obtained without being affected by the propagation velocity Vs of the ultrasonic signal in the magnetostriction 1 and regardless of the mechanical contact portion.

In addition, in the calculation circuit CS, it may be allowed to perform the same poor as in the expression (4).

In this case, since the output signal E ₀ is affected by the propagation velocity Vs of the ultrasonic signal, it is preferable to use a material for which the propagation velocity does not change excessively due to temperature or the like, for example, Ni-SPANC.

The device configured in this way has one of the features in that the excitation means 4 for generating the ultrasonic signal in the magnetostriction 1 is arranged between the two receiving means 2 and 3, and thus the ultrasonic signal is excited by the arrangement. It is to propagate on the same condition from 2 to left and right, and by calculating t ₁ -t ₂ , it is easy to error by time delay from applying excitation pulse PE to excitation means 4 and then actually generating ultrasonic signal in magnetostriction 1. It can be removed.

로 하면, 예컨대 (4)식은 E₀=(t₁+

)-(t₂+

)=t₁-t₂로 되어

의 영향이 없어진다.In other words, this time delay

For example, the expression (4) is represented by E ₀ = (t ₁ +

)-(t ₂ +

) = t ₁ -t ₂

The influence is gone.

In addition, in the apparatus of FIG. 1, since both the first receiving means 2 and the second receiving means 3 can be fixed to the magnetostriction line 1, these means are housed in a sealed case or the like, so that the external noise ( It is effective to eliminate the effects of noise.

3, 4, and 5 are schematic diagrams showing another embodiment of the present invention. The embodiment device of FIG. 3 combines the magnetostrictive line 1 to the movable part 5, and the excitation means 4 to the magnetostrictive line 1. It is interposed between the 1st receiving means 2 and the 2nd receiving means 3, and is arrange | positioned so that the magnetostriction line 1 and the excitation means 4 can move relatively.

In addition, both the 1st receiving means 2 and the 2nd receiving means 3 are being fixed in the vicinity of the both ends of the magnetostriction 1. As shown in FIG.

Therefore, in this apparatus, in response to the mechanical displacement of the movable part 5, the magnetostriction line 1, the first receiving means 2 and the second receiving means 3 move in the directions of the arrows a, b, and the distance between the excitation means 4 and the first receiving means 2 The distance 1 ₂ between the 1 ₁ and the excitation means 4 and the second receiving means 3 likewise translates in relation to the mechanical displacement.

The electrical circuit means is the same as that of the first FIG. Device, and the device thus constructed is effective in the case where the mechanical displacement is a micro displacement, for example, corresponding to the differential pressure or the pressure.

In the embodiment of FIG. 4, the excitation means 4 is fixedly arranged at the center of the distance of the magnetostriction 1, and the first receiving means 2 and the second receiving means 3 are respectively coupled to the movable portion 5 to correspond to the mechanical displacement, thereby receiving the first reception. The means 2 and the second receiving means 3 are configured to move along the magnetostriction 1.

In the embodiment of Fig. 5, the excitation means 4 is fixedly arranged at the center of the distance of the magnetostriction 1, and the first receiving means 2 is arranged so as to be able to move along the magnetostriction 1 in response to the mechanical displacement, and the second receiving means 3 is fixedly placed at one end of the other side of magnetostriction 1.

Therefore, while the distance between the excitation means 4 and the first receiving means 2 changes in correspondence with the mechanical displacement, the distance between the excitation means 4 and the second receiving means 3 is kept constant. Therefore, as shown in the figure, when the distance 1, x is determined, the time width t1 of the signal obtained by the flip-flop circuit FF ₁ is expressed by the equation (5), and the time width t _{2 of the} signal obtained by the flip-flop circuit FF ₂ is represented. Are respectively represented by (6).

The arithmetic circuit CR takes these signals as inputs, and for example, can perform the following calculation to obtain a signal E ₀ related to the mechanical displacement position x.

Further, in the present example, the operation circuit CK, the flip-flop circuit FF _1, between the stranded the control gate (Gate) circuit GA _1, GA ₂ The gate circuit GA _1, GA ₂ is by a signal from the FF ₂ And a counter Cu ₁ , Cu ₂ that counts a clock pulse CLK applied thereto, and a microprocessor μp that takes in digital signals from these counters Cu ₁ , Cu ₂ .

The microprocessor μp may not only perform an operation as shown in Eq. (6) but may also perform an operation or other correction operation as necessary because of, for example, a liner riser.

The calculation result can be obtained as a digital signal in a microprocessor μp or as an analog signal through a D / A converter (not shown), respectively. 6 and 7 are diagrams showing the application of the device of the present invention, and FIG. 6 is a case where it is applied to a level meter, and the excitation means 4 is coupled to float 5, which is a movable part. In response to the liquid level displacement in the tank 6, it is possible to move up and down along the magnetostriction 1.

7 shows the case where the differential pressure transducer is applied, the connecting rod connecting diaphragms 51 and 52 is composed of magnetostriction 1, and the first receiving means 2 and the second receiving means 3 are fixed to both ends of the magnetostrictive wire 1. The excitation means 4 is fixed to the body 8 so as to be fitted to the first receiving means 2 and the second receiving means 3.

The diagrams 51 and 52 are displaced according to the pressure difference introduced into the rooms 71 and 72 formed on both sides thereof, and the magnetostrictive line 1, the first receiving means 2 and the second receiving means 3 displace together.

FIG. 8 is a configuration explanatory diagram showing Example 1 in the case where the displacement position converting apparatus of the present invention is applied to a position return means in an automatic balancing instrument, and here is a case where it is applied to a recorder.

In the figure, 7 is a scale plate disposed at the front of the instrument, 70 is a guide rail disposed in parallel with the scale plate 7, 5 is a movable portion that moves along the guide rail 6, instructions 50, recording pen 53, And an excitation means 4 of the support portion 55 and the support portion 55 bonded to the guide rail 70 and the position return means 9 described later.

71 is the irradiation attached to the holding part 55, and is suspended by the drive-pull 75 connected to the balance motor 74 via Pulley 72,73.

8 is a recording sheet fed in the direction of arrow a, and in the position return means 9, the magnetostriction 1 is arrange | positioned substantially in parallel with the guide rail 70. FIG. The excitation means 4 moves together with the movable portion 5 and generates an ultrasonic signal at the magnetostriction 1, and receiving means 2 and 3 for ultrasonic signal are fixedly arranged at both ends of the magnetostriction 1, respectively.

A coil and a piezoelectric element are used for these receiving means, for example, and the excitation means 4 is a coil, for example, couple | bonded with the magnetostriction line 1, and the state caught between the 1st receiving means and the 2nd receiving means across this magnetostriction line. It can be moved as the movable part 3.

9 is an electric circuit diagram showing an example of the apparatus shown in FIG.

In the figure, Ei is an input signal to be measured and recorded, AM is an amplifier that inputs the deviation ε between the input signal Ei and the return signal Ef from the calculation circuit CK, and forms a balanced motor 74 according to the deviation ε.

When the balanced electric motor 74 is driven, the movable portion 5 moves one after another on the guide rails, and the excitation means 4 moves one after the magnetostriction 1 with the irradiation 71 therebetween.

The feedback signal Ef related to the movable part 5 position X obtained by the arithmetic circuit CK is given to the deviation detecting circuit EA, and the loop including the dilator AM and the balance motor 74 moves the movable part 5 so that Ef = Ei. And auto balance there. Therefore, the movable portion 5, that is, the recording pen 53 can be accurately followed the input signal Ei, and the magnitude of the input signal Ei can be known at the recording position.

10, 11, 13, and 14 are diagrams showing some examples of the excitation means used in the apparatus of the present invention. In the example of FIG. The signal generated in the secondary winding of the transformer 40 and the transformer 40 having an iron core on a donut which acted as a secondary winding and was free to move along the magnetostriction 1 was applied. The excitation coil 41 is coupled to the magnetostriction 1.

The excitation pulse signal PE from the excitation pulse generator OS can be supplied to the magnetostriction 1, and when the excitation pulse is supplied to the magnetostriction 1, it is positioned at the position where the coil 41 of the magnetostriction 1 exists between the transformers 40. It can generate an ultrasonic signal.

In this embodiment, the gate circuits G ₁ and G ₂ are provided on the output sides of the comparison amplifiers OP ₁ and OP ₂ , and are excited by the output signals of the monostable multi-vibrator circuits MM ₁ and MM ₂ . By closing the gate circuits G ₁ and G ₂ for a fixed time τ ₁ , τ ₂ after the pulse signal PE is supplied, the noise generated between τ ₁ and τ ₂ after supplying the excitation pulse signal is effectively I can stop it.

In the example of FIG. 11, aftershock means 4 is itself a permanent magnet which intersects the magnetostriction 1. In addition, the excitation pulse from the excitation pulse generator OS can be supplied to the magnetostriction 1. When the excitation pulse signal PE flows on the magnetostriction 1, as shown in FIG. 12, the magnetic field F ₁ and the permanent magnet by the excitation pulse current are shown. Due to the interaction of the four magnetic fields F ₂ , the balance of the magnetic field distribution is dispersed, and an ultrasonic signal is generated in the magnetostriction 1 at the position where the permanent magnet 4 is present.

In the example of FIG. 13, the excitation means 4 is comprised as FIG. 10, but the means which supplies the excitation pulse signal PE to the magnetostriction 1 differs. That is, the magnetostrictive line 1 constitutes an electric Perup by the conductor 10, and the excitation pulse is excited by the excitation pulse generator OS 4 through a current trans former CT in which the conductor 10 functions as a secondary winding. To be able to supply.

Here, the excitation pulse can be supplied to the magnetostriction 1 at a position slightly away from the cross section of the magnetostriction 1 such that the excitation pulse PE does not flow to the portions of the receiving coils 2 and 3.

In the example of FIG. 14, the current trans CT having the iron core which constitutes the irradiation for driving the movable part 5 or the excitation means 4 as a conductive material and which this irradiation 71 serves as a secondary coil and which the irradiation can move freely is shown. The excitation pulse PE in the pulse generator OS is supplied to the excitation means 4 in between.

The excitation means 4 is electrically in contact with this irradiation, and an aftershock pulse is given between the irradiation 70.

As shown in Figs. 10 and 11 and 13 and 14, the excitation means 4 is constituted as shown in the figure, so that the lead wire for supplying the excitation pulses is not particularly necessary, so that the configuration is simplified, and the closing of the guide is not possible. It is effective to eliminate the disconnection caused by the back.

FIG. 15 is another block diagram of the device of the present invention. In this embodiment, one end 11 of the magnetostriction 1 is configured to reflect the ultrasonic signal generated in the magnetostriction 1, and at the other end of the magnetostriction 1, The receiving means 20 serving as both of the receiving means and the second receiving means is provided.

Excitation means 5 is applicable here, as the case shown in FIG. 10 applies.

FIG. 16 is a cross-sectional configuration diagram of the magnetostriction line 1, the transportation means 20, and the excitation means 4 in the apparatus shown in FIG. 15, wherein the meridian 1 is composed of a hollow pipe, and at both ends thereof, for example, rubber, Vibration damping material IS, such as plastic, is impeded by outer port B ₀ .

This prevents mechanical vibrations in the outer sphere B ₀ from being transmitted directly to the magnetostriction 1.

Receiving means 20 is a bobbin 22 through which the magnetostriction 1 penetrates, the receiving coil 21 wound here, the shield plate 24 disposed on both ends of the coil 21 and the shield plate connect to each other, and the case of the coil 21 like the shield plate 24 ( The permanent magnet 23 constitutes a case.

The permanent magnet 23 plays a role of increasing the detection sensitivity by giving the magnetostriction 1 a DC magnetic field of a suitable size.

The aftershock means 4 is comprised with the bobbin 42, the aftershock coil 41 wound up, the shield plate 44, the permanent magnet 43, and the case 45 which housed the trans | transmission 40 here.

The part except the trans | transmission 40 and this case 45 is comprised substantially similarly to the receiving means 20, and the permanent magnet 43 plays the role which produces | generates the ultrasonic signal efficiently to the magnetostriction 1.

In the apparatus of FIG. 15, the ultrasonic signal generated at the excitation means 4 and propagated toward both ends is initially propagated.

When the signal propagated to the left side from the excitation coil 41 reaches the position of the receiving coil 20, the receiving coil 20 detects a signal such as the display of e ₁ in FIG. 17B.

The signal propagated from the excitation coil 41 to the right side is reflected at the cross section 11, returns to the magnetostriction 1 again, reaches the receiving coil 20, and is detected by the receiving coil 20 as indicated by e ₁ in FIG. 17B. The signals e ₁ propagated directly from the excitation coil 41 to the receiving coil 20 and the signals e ₂ reflected and propagated in the cross section 11 have different polarities as shown here, but depending on the conditions of the cross section 11, It is also possible to make it polar.

The time t ₁ until the signal e ₁ is detected by the receiving coil 20 after applying the excitation pulse to the PE of FIG. 17a corresponds to the distance 1 ₁ between the excitation coil 41 and the receiving coil 20, and the signal e _2. The time t ₂ until is detected is a total of 1 ₁ +1 ₂ +1 ₂ of the distance 1 ₂ between the excitation coil 41 and the end face 11 and the distance 1 ₁ , 1 ₂ (constant) between the end face 11 and the receiving coil 20. It corresponds.

The comparison amplifier op1 selects the first positive reception signal e ₁ detected among the signals in the reception coil 20 and resets the flip flop circuit FF ₁ to the reset state. As described above, the comparison amplifier op ₂ selects the negative receiver e ₂ of the signals in the receiving coil 20, sets the flip-flop circuit FF ₂ to the reset state, and the calculation circuit CK calculates as shown in Equation (3).

According to the device configured as described above, there is an advantage that one receiving coil can obtain a signal that is exactly proportional to the position x of the side of the movable part 5 without being affected by the propagation speed VS.

FIG. 18 and FIG. 20 are connection diagrams showing an example of the calculation circuit CK used in the apparatus of the present invention. In FIG. 18, the switches SW ₁ and SW ₂ are conducted by the time-width signals PW ₁ and PW ₂ in each flip-flop circuit, and the integrator INT including the capacitor C ₁ and the operational amplifier op ₃ is the resistor R. ₁ , the reference power supply voltage + es applied across the switch SW ₁ and the reference power supply voltage -es applied across the resistor R1 and the switch SW ₂ are respectively integrated.

Now, if the absolute values of the reference supply voltages + es and -es are the same, the period during which the switches SW ₁ and SW ₂ are conducting together is the integrator with the resistors R ₁ , switches SW ₁ and SW ₂ together. Since it is applied to the input terminal of INT, the zero state is maintained as shown in FIG. 9E of the output voltage E ₁ .

In a state in which only _one switch SW ₁ or SW ₂ is conducting (here, the switch SW2 is conducting), either of the polarity reference power supply voltage es is applied to the integrator INT across the resistor R1.

Therefore, the output voltage E ₁ of the integrator INT can be expressed by (7).

In the formula (7), C ₁ and R ₁ are constant values as the capacitance and the resistance of the capacitor, and Es is also a constant value.

Therefore, the output voltage E ₁ of the integrator INT after t ₂ passes corresponds to tt _2, that is, 1 _{1-1 2} .

The signal E _I related to the position of the movable section 5 thus obtained is sampled by the sampling pulse SP as shown in FIG. 19f obtained from the mono multi circuit M ₁ , and at the output terminal OUT of the sample circuit SH. It is output as shown in FIG. 19G.

The electric charge of the capacitor C ₁ of the integrator INT is set after the predetermined time has elapsed, and the switch WS ₃ is closed and determined by the reset pulse RP in the monomulti circuit M ₂ . (See FIG. 19e, 19g). In FIG. 20, in the circuit of FIG. 18, the output voltage E ₀ of the sample hold circuit SH is given to the input terminal of the integrator INT with the lead wire F ₁ , the resistor R ₂ , the switch SW _1, and the switch SW ₂ . At the same time, the reset switch of the capacitor C ₁ is omitted.

In the circuit configured as described above, when 1 ₁ = 1 ₂ (t ₁ -t ₂ ) is changed to 1 ₁ = 1 ₂ , a signal changing in steps for each period of the sample pulse SP is obtained as the output signal E ₀ . If R ₁ = R ₁₁ = R ₁₂ , R ₂ = R ₂₁ = R ₂₂ , the equation (8) is obtained in the steady state after several cycles.

Therefore, compared with the calculation circuit shown in FIG. 18, the calculation circuit of FIG. 20 is advantageous in that it is not influenced by the propagation speed VS of the ultrasonic signal and is not affected by the value of the capacitor C ₁ or the like.

In this circuit, the displacement and output of the movable part are connected by connecting the resistor R ₀ to the lead wire F ₁ as indicated by the broken line and adjusting the resistance _values of the resistors R ₁₁ , R ₁₂ , R ₂₁ , R ₂₂ and R ₀ as appropriate. The relationship of the voltage E ₀ can be made into a nonlinear relationship such as A, B, C, and D in FIG.

FIG. 22 is a block diagram showing the case where the apparatus according to the present invention is applied to an automatic balancing instrument. In this example, the circuit of FIG. 20 is used for the calculation circuit CK.

In this figure, es is the bias signal to set the zero position (reference position) of the guideline 50, which is the moving part, and the balance motor 74 moves the guideline 51 such that E ₁ + e _B = E ₀ .

In this circuit, the input signal E1 and the vise signal e _B are provided to each terminal (-) of the operational amplifier op _{4 with} a resistance therebetween, and the balanced motor 74 is used as the output signal of the operational amplifier op ₄ . You may make it drive. Alternatively, the input signal E ₁ or the bias signal e _B may be applied to the input terminal of the integrator INT with the resistors R ₃ , the switches SW ₁ , and SW ₂ interposed therebetween as indicated by the broken lines.

In these cases, the amplifier AM can be omitted by bringing the op amp op ₄ with a constant gain.

In addition, this circuit can be applied as it is even when one end of the magnetostriction 1 is configured so that an ultrasonic signal is reflected and the other end is provided with one receiving means that combines the first receiving means and the second receiving means. May be configured by combining the characteristic circuit portions shown in the above-described embodiments.

Claims (1)

As described above in the text and as shown in the drawings, a magnetostrictive wire made of a magnetostrictive material, a first receiving means and a second receiving means for coupling to the magnetostrictive wire, and a magnetostrictive wire coupled to the magnetostrictive wire and interposed therebetween Change the excitation means arranged in the first receiving means and the second receiving means and the distance between the excitation means and the first receiving means or the distance between the excitation means and the second receiving means corresponding to the mechanical displacement. A signal corresponding to the mechanical displacement using two kinds of signals relating to the time required for causing the signal generated in the magnetostriction line by the excitation means to reach the first receiving means and the second receiving means. Displacement position converting apparatus having a computing circuit means for obtaining a.

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