SU771197A1 - Automatic device for controlling thickness of galvanic plating - Google Patents

Description

(54) DEVICE FOR AUTOMATIC CONTROL AND REGULATION OF GALVANO COATING THICKNESS

one

The invention relates to the field of electroplating and can be used to automatically control and regulate the thickness of coatings during the electrodeposition of 5 metal.

A device for automatically controlling and adjusting the thickness of electroplating is known, comprising a series-connected current sensor 10, an amplitude-to-pulse width converter, a frequency divider and a pulse counter with a control circuit fl. This device is the closest to the proposed 5 by the technical essence and the achieved result.

The disadvantages of the known device consist in the complexity of the circuit, and also in the fact that in this device the determination of the coating thickness is reduced to a large-scale recalculation of the number of pulses, the frequency of which is proportional to the thickness of the coating; since the known current transducers 25 (voltages) to the pulse frequency can work normally only at relatively high frequencies (several hundred hertz), i.e., a frequency divider and a pulse counter of a known device

The device must be large, which further complicates its design and reduces reliability.

The purpose of the invention is to increase the reliability of work during long processes.

The goal is achieved by the fact that the device is equipped with a reference frequency generator, connected to an amplitude-to-pulse width converter, and the frequency divider is designed as an integrating one. a variable division counter, which is made on a ferromagnetic ring core with a rectangular hysteresis loop.

FIG. 1 shows a block diagram of the proposed device; FIG. 2 is a block diagram of an amplitude converter into a pulse width; fig.z electrical frequency divider circuit.

The device consists of series-connected current density sensor 1, converter 2 amplitude to pulse duration, synchronized by reference frequency generator 3 (as which, for example, an industrial network with a frequency of 50 Hz can be used), 4 frequency divider with a variable division factor, in the form of an integrating counter on a ferromagnetic ring core with a rectangular hysteresis loop / and a counter 5 pulses with presetting inputs connected to Locke used control. The amplitude-to-pulse-width converter is designed as a series-connected generator 7 of the sawtooth voltage and Comparator 8. The device operates as follows. The clock pulses the generator of the sawtooth voltage 7, which is fed to the first input of the comparator 8. The other input of the comparator receives voltage from the current density sensor . At the output of the comparator 8, pulses are generated, the duration of which is proportional to the voltage from the current density sensor multiplied by the current utilization factor (specified by the conversion law of the converter), and the frequency is equal to the frequency of the master oscillator 3. The generated pulses are supplied to the divider 4 frequency input with a variable division factor made on a ferromagnetic ring with a rectangular hysteresis loop, where the property of ferromagnetic materials with a square hysteresis line is used pulses in their volt-second area. Thus, the pulse repetition frequency at the output of the splitter 4 frequency will depend on the pulse duration, i.e. from the captured signal from the sensor. If a number equal to the difference between the total capacity of the meter and the calculated number of pulses providing the specified coverage is entered into the counter of 5 pulses before the process starts, then at the nominal mode. The calculated amount of pulses, the counter will overflow and c. its output will generate a signal to end the process. For the preliminary rjn s s-; ™ - This technical solution allows controlling rather long processes, such as electroplating processes, having a simpler circuitry compared to a known device with a small counter capacity and frequency divider, which, in turn, improves the reliability of the cJyJL JJ its formulas of the invention 1. Device for automatic control and regulation of the thickness of electroplating, containing series-connected, current sensor, amplitude converter in the duration Pulse impedance, a frequency divider and a pulse counter with a control unit, characterized in that, in order to increase reliability during long processes, it is spun by a master frequency reference generator connected to an amplitude-to-pulse converter, and the frequency divider is designed as an integrating counter variable division ratio. 2. A device according to claim 1, characterized in that an integrating counter with a variable coefficient is made on a ferromagnetic ring with a rectangular hysteresis loop. The sources of information, rintye taken into account during the examination 1. USSR Copyright Certificate 401753, cl. C 25 D 21/12, 1972.

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Claims (2)

Claim 2Q 1. Device for automatic control and regulation of the thickness of electroplated coatings, comprising a current sensor connected in series, an amplitude to 25 pulse converter, a frequency divider and a pulse counter with a control unit, characterized in that, in order to increase reliability during long-term processes, it is equipped a reference frequency reference oscillator connected to an amplitude to pulse converter, and the frequency divider is made in the form of an integrating counter with variable coefficients event division. 35 2. The device according to π.1, characterized in that the integrating counter with a variable division coefficient is made on a ferromagnetic ring with a rectangular hysteris loop 40.