Automated Control System for a Mechanized Perforated Non-Conductive of Electric Current Screen of an Electroplating Bath

The article discusses the design of a non-conductive of electric current mechanized perforated screen, which provides vertical openings along which curtains move, connected by cables with stepper motors. The optimization problem is set and solved: for a given shape and size of the part, find the type of  blinds for each hole and the coordinates of the edges of the blinds at which the criterion of unevenness of the electroplating reaches a minimum. А two-level structure of an automated control system for a mechanized perforated screen is proposed. The upper level includes a computer, which searches for the optimal configuration of holes in the screen. The lower level includes a controller that, after receiving information from an upper-level computer, controls the stepper motors through drivers. The mathematical and software support control systems are described. To calculate the coating thickness, Faraday’s law is used; to determine the current density at any point in the galvanic bath, Ohm’s law is used in differential form; to find the potential distribution in the electrolyte volume, the Laplace differential equation with nonlinear boundary conditions of the 3rd kind is used. The central equation of the mathematical model is the Laplace equation, which is solved by combining the methods of splitting and relaxation with a string run-through. An example of solving an optimization problem for a part of complex shape is given. The use of the developed device and control system significantly reduces the cost of obtaining a galvanic coating with a given unevenness due to its versatility, since there is no need to manufacture screens for each coated part, when differing in shape and size.

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