RU1772623C - Magnetostriction displacement transducer - Google Patents

Abstract

The invention relates to the field of computer engineering and automation. The aim of the invention is to increase the noise immunity with changing ambient temperature or voltage fluctuations of power sources. When processing the direct and reflected signals propagating through a magnetostrictive sound path, two comparators, a second time driver, and two inverters are used, which eliminates spurious oscillations of these signals. 3 ill.

Description

The invention relates to the field of computer engineering and automation.

A device for an ultrasonic transducer is known, comprising a waveguide, a transmitting coil, two receiving coils, comparators, logical and analog shapers 1.

Closest to the invention is a magnetostrictive displacement transducer comprising a magnetostrictive sound pipe with dampers at the ends, a pulse generator connected in series and a transmitting coil fixedly mounted on the sound pipe, a permanent magnet receiving coil mounted on the sound pipe with the ability to move, a temporary shaper, switch and delay line 2.

A disadvantage of the known device is its low noise immunity due to the influence of changes in the ambient temperature and voltage fluctuations of the power sources.

The aim of the invention is to increase the noise immunity.

This goal is achieved in that a magnetostrictive transducer comprising a magnetostrictive sound pipe with dampers at the ends, a pulse generator in series, and a transmitting coil fixedly mounted on the sound pipe, a receiving coil with a permanent magnet mounted on the sound pipe with the ability to move, a temporary shaper, a switch and a line delays, equipped with two comparators connected to the output of the receiving coil, a second temporary driver, two inverters and connected to the output of the switch in series with an integrator and an operational repeater, the output of which is designed to be connected to the registrar, the output of the first comparator is connected to R - the input of the first temporary driver, S - the input of which is connected to the output of the second comparator, the second

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the input of the first comparator through the first inverter is connected to the input of the delay line, the output connected through the second inverter to the first input of the switch, the second input of the switch is connected to the inverse output of the second temporary driver, S is the input connected to the pulse generator, R is the input to the output of the first temporary driver, the second output of which is connected to the third input of the switch, the fourth input of which is designed to be connected to a power source, the second input of the second comparator is connected to the inverse output m of the second temporary shaper, and the dampers are made in the form of flaring the ends of the sound duct.

Figure 1 shows a block diagram of a magnetostrictive transducer; figure 2 is a timing diagram of the blocking of ultrasonic spurious oscillations p of the Converter; Fig. 3 is a timing chart of the operation of the converter.

The magnetostrictive displacement transducer consists of a magnetostrictive sound conduit 1, at one end of which there is a stationary cylindrical transmitting coil 2 connected to the output of the clock power amplifier 3, and a movable receiving cylindrical coil 4 with a permanent magnet 5 connected to the inputs of two comparators 6.7 - direct and reflected signals connected by outputs to the logic circuit of the first temporary driver 8, the outputs of the second temporary driver 9 are connected to the analog switch shaper 10, switch 10 outputs are connected to the integrator 11 and the operational repeater 12, the output of which is external output magneto- striction transducer linearly movable and the inverters 13, 14.

The device operates as follows. The clock signal is fed to the pre-shaper (PF) of the power amplifier 3, from the output of the pre-shaper, the signal is simultaneously fed to the input of the output stage of the VK power amplifier 3 and shaper 8, which by the inverse output signal turns on the short-circuit key of the analog switch 9 and brings the integrator 10 to its original state nie. Simultaneously, from the output stage BK of the power amplifier 3, an electric pulse acts on the transmitting coil 2 located on the sound duct 1. In the coil 2, a pulsed magnetic field arises, which excites mechanical ultrasonic waves in the tubular sound duct 1. These waves propagate through the sound conduit 1 at an ultrasonic speed, and, having passed through the receiving coil 5, they excite electric vibrations in it (direct signal). When it reaches the end of sound duct 1, the mechanical ultrasonic wave is reflected from the end of the waveguide and, having passed the receiving coil 5 again, again

0 excites electric vibrations in it (reflected signal). The reflected mechanical ultrasonic wave, reaching the start of the sound duct 1, the reflection undergoes a significant attenuation, due to the radial

5 the expansion of the end of the tubular waveguide located on the side of the transmitting coil.

Excited pr ms-L electric signal in the coil is fed to the comparator

0 7, which forms a rectangular pulse of the direct signal. This signal from the output of the comparator 7 is fed to a temporary driver 9, which translates the signal from a non-inverse output

5 8 to the initial state. From the inverted output of the driver 9, the signal turns on the analog switch K1 of the switch 10, and the capacitor of the integrator 11 starts charging from the reference source

0 resistor. An electric signal of reverse polarity excited by the reflected wave is fed to comparator 6. which generates a rectangular pulse of the reflected signal, key K1 opens and

5, the capacitor of the integrator 11 is disconnected from the reference source (HEY). Simultaneously with the inverse output of the driver 8, the signal is fed to the differentiating circuit of the inverter 13, the signal from the output of which

0 turns on the key K2 of the analog switch 10. The signal from the output of the integrator 11 is supplied to a dynamic memory consisting of a capacitor and an operational analog repeater 12. At the output, repeat 5 l 12 and a constant voltage is generated which is proportional to the linear displacement.

The resistive circuit R2 operates as follows.

0 After the shaper 9 is switched by a clock pulse, the low-level signal from the inverse output of the shaper 8 is fed through the resistor R2 to the inverse input of the comparator 7. prepare it for

5 receiving a direct signal. After the direct signal arrives, the shaper-8 returns to its initial state and transfers the comparator 7 to the mode by means of a high-level signal via R2, which prevents the circuit from triggering from parasitic reflected signals (see Fig. 2, c). The delay circuit RO, C1, inverter 14, R1 operate as follows. After switching the formers 8, And and after a time determined by the delay circuit R3, C1, a high-level signal appears at the output of the inverter 14, coming through R1 to the non-inverse input of the comparator 6 and preparing it for receiving the reflected signal, After the reflected signal arrives the signal shaper 9 goes into its initial state and, through the inverter 14, transfers the comparator 6 to a mode that prevents the circuit from triggering spurious signals (see Fig. 2, a).

The radial flaring made at the end of the sound pipe 1 from the side of the transmitting coil 2 acts as a damper to reflect the signal from the flared end, because the flaring distorts the structure of the crystal lattice of the sound duct 1 at the place of flaring and contributes to the attenuation of the reflected signal.

Using the invention will improve the reliability of the converter. Reduces threshold requirements for comparators and their adjustment.

Claims (1)

Formula of the invention I Magnetostrictive displacement transducer containing magnetostrictive sound pipe with dampers at the ends, serially connected pulse generator and transmitting coil fixedly mounted on the sound cable, receiving coil with a permanent magnet mounted on the sound pipe with the possibility of movement, temporary shaper, switch and delay line, characterized in that, in order to increase the noise immunity, it is equipped with two comparators connected to the output of the receiving coil, the second a temporary shaper, two inverters and connected to the output of the switch in series with an integrator and an operational repeater, the output of which is designed to be connected to the registrar, the output of the first comparator is connected to the R-input of the first temporary shaper, the S-input of which is connected to the output of the second comparator, the second input of the first comparator through the first inverter is connected to the input of the delay line, the output connected through the second inverter to the first input of the switch, the second input of the switch is connected to the inverse output of the second temporary shaper, S-input connected to f pulse generator, R-input - with the output of the first temporary shaper, the second output of which is connected to the third input of the switch, the fourth input of which is designed to connect to a power source, the second input of the second comparator is connected to the inverse output of the second temporary shaper, and dampers are made in the form of flaring ends of sound ducts. 50 h ya & o ЈseЈ .FO№73 $ М9Ј Ы А & Л & ЛЬ Я .CW &&  X0 / РЗ & МУЯЈ # & A Јsssag: ts % / fafVUt /