SU1277026A1 - Meter of electrostatic charges - Google Patents

Abstract

The invention relates to measurement technology and is intended for. measurements of electrostatic field strength or charge density on the surface of stationary or moving electrified dielectric materials. The aim of the invention is to improve the measurement accuracy by eliminating the dependence of indications on the number of revolutions of the motor, as well as by introducing a synchronous detector. The electrostatic charge meter contains n sensitive electrodes 2-5, made in the form of sectors, modulator 1, differential amplifier 6 and indicating device 15. In addition, n synchronous detectors 7-10, a reference voltage generator including a driver 11 are inserted into it. control sync pulses and a distributor 12 control sync pulses, a torus-inverter 13 and a smoothing (L filter 14. The modulator 1 is made-in the form of a metal disk with a sector-shaped hole elec- tion, trodes. 2 yl. w w SP

Description

"1 The invention relates to a measurement technique and is intended to measure the electrostatic field strength or density of a charge on the surface of stationary or two electrified dielectric materials. The purpose of the invention is to measure the measurement accuracy by eliminating the dependence of the indications on the speed S of the motor and also introducing a synchronous detector . Hci of FIG. 1 is a structural electrical circuit meter for electrostatic charges; in fig. temporal stress diagram explaining its operation. The device contains a primary converter, made in the scattering electrode 1, provided with a sector-shaped hole and a motor mounted on the shaft and a measuring electrode, including sensitive components 2-5 of the sector form, insulated from each other, connected to the inputs of the amplifier 6, which is made potential The output is connected to the signal inputs of synchronous detectors, the control inputs of which are connected to the corresponding outputs of a voltage generator, made in the form of successively connected driver synchro pulses 11 and a distributor 12 control, and their pulse signals. The outputs of the even-numbered synchronous detectors 8 and 10 are connected via the repeater-inverter 13 and the matching firing pin 14 to the input of the indicating device. The outputs of the odd synchronous detectors 7 and 9 are connected to the input of the smoothing filter 1 4. . The electrostatically charged charge meter operates as follows: l When the screen rotates, its electrode 1 successively opens (exposes) the sensitive elements 2-5 and induces electrostatic charges to Hsrx. At the same time, the potential of the operating elements 2–5 is formed by the potentials of the alternating electrical signals that arrive at the corresponding inputs of the differential amplifier 6 in a certain sequence: from the odd sensitivity 6 of the switching elements 3 and 5 to the inverting input and from the even Hbix sensors elements 2 and i are non-inverted input inputs. At the same time, at the output of amplifier 6, an electrical signal is generated (FIG. 2a), which is fed to the inputs of synchronous detectors 7-10. Their operation is controlled from ci-pulse pulses (Fig. 2–5, e, f) taken from the corresponding outputs of the distributor 12. In turn, pulses arrive from the control puller 11 to the input of the distributor 12 (Fig. 26). a duty cycle equal to the exposure time of the sensitive elements 2-5. Each of the synchronous detectors 7-10 is successively unlocked and passes the corresponding half-waves of the input signal to the output (fig.2h, h, and, k). Using the inverter 13, the negative is inverted . semi-volvol (2c, k) supplied from the synchronous detectors 8 and 10, 13 are positive (Fig. 2n). Together with the positive half-waves (fig.2h, and) 5 taken from the outputs of synchronous detectors 7 and 9, they form a sequence (fig.2m), similar to the signals at the output of a full-wave rectifier. . which enters through the cr, 11pazha) common filter 14 on the trick showing the device 15, If the charges of static electricity change the CBoii sign to the opposite, 7.e. become, for example, negative, then the scheme of operation works in a similar way and at its output otrip, exactly, the 1st half-wave of the full-wave rectification, are formed (fng. 2a, f, m, dotted line). The use of dual-phase synchronous detection in a camera allows one to increase the constant component of the signal by a factor of 2 compared to single-period synchronous detection and make its sensitivity independent of the screen rotation speed or exposure frequency. The use of differential amplification of a single signal increases the noise immunity of the meter. F with ryyu l isoooreteni (Electrostatic charge meter, contains the sensitive electrodes, made in the form of sectors, the modulator mounted on the shaft

a motor, a differential amplifier, the inverting input of which is connected to odd sensitive electrodes, and the non-inverting input to even, and showing a device, characterized in that, in order to increase the accuracy and sensitivity of measurements, it introduces synchronous detectors, a reference voltage generator, a repeater an inverter and a smoothing filter, while the modulator is made in the form of a metal disk with a sector-shaped hole, the area of which is equal to the area of the sensitive zlaktod, the output is differential effort

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the bodies are connected to the signal inputs of the synchronous detectors, the outputs of the odd synchronous detectors are connected directly to the smoothing filter, the outputs of the even synchronous detectors are connected to the smoothing filter through a repeater-inverter, the output of which is connected to the indicating device, and the control inputs of the synchronous detectors are connected to the outputs of the indicating device, and the control inputs of the synchronous detectors are connected to the outputs of the indicating device, and the control inputs of the synchronous detectors are connected to the outputs of the indicating device. made in the form of serially connected driver clock sync pulses and control clock sync pullers.

Claims (1)

Claim" 5S An electrostatic charge meter containing η sensitive electrodes made in the form of sectors, a modulator mounted on the motor shaft, a differential amplifier whose inverting input is connected to odd sensitive electrodes, and a non-inverting input is connected to even ones, and showing 5 device, characterized in that , in order to improve the accuracy and sensitivity of measurements, η synchronous detectors, a reference voltage generator, a repeater-inverter and a smoothing filter are introduced into it, while the module The OR is made in the form of a metal disk with a sector-shaped hole, the area of which is equal to the area of the sensitive electrode 15, the differential amplifier output is connected to the signal inputs of synchronous detectors, the outputs of the odd synchronous detectors are connected directly to the smoothing filter, the outputs of even synchronous detectors are connected to the smoothing filter through a repeater-inverter, the output of which is connected to a indicating device, and the control inputs of synchronous detectors are connected to the outputs of the generator ornogo voltage, configured as a series-connected control clock generator and distribution control clock divider. t m —I I — I 1-1 - t T ______ I — L ί — 1. t _______ ί — 1 _____ 1—1 t 1-1 1—1 1 — If Λ Λ A f Ζ \ / GU / - ( \ / V Λ ) ---------- (> - - / \. t Fig. 2 Compiled by E. Pluzhnikova Editor K. Voloshchuk Tehred V. Kadar Proofreader M. Samborskaya Order 6662/38 Circulation 728 Subscription VNIIIPI of the USSR State Committee for Inventions and Discoveries 113035, Moscow, Zh-35, Raushskaya nab., D. 4/5 Production and printing company, Uzhgorod, Project 4,