Abstract: An apparatus for automatically maintaining plating current density within a predetermined range while controlling plating current to produce a desired plating thickness includes means for energizing only the number of plating cells required to maintain plating current density within the predetermined range. The total plating current required to produce the desired plating thickness is distributed among the energized plating cells. Decreases in the number of energized plating cells is made at speed values which are less by a hysteresis value than speeds at which the number of energized plating cells is increased to avoid instability due to normal speed reading variations.

Abstract: An apparatus in which plating currents of a plurality of successive plating cells are normally automatically controlled in accordance with line speed to maintain uniform plating thickness, and in which the number of energized plating cells is increased or decreased in accordance with line speed to maintain plating current density within a predetermined range, includes tracking or timing facilities for progressively changing plating currents of plating cells in correspondence with movement of the strip being plated through the cells after the number of energized cells has been increased or decreased so as to reduce plating thickness variation on the portion of the strip within the plating cells at the time of the change in the number of energized cells.

Abstract: A method and apparatus for automatically changing a plating thickness in an electrical plating line in which unwanted over-plating is prevented. The plating line includes a plurality of plating tanks through which a member to be plated is conveyed and corresponding plating current sources. As a plating thickness change point on the member to be plated passes through the various tanks, a first plating current corresponding to a first plating thickness is applied through plating current power sources before the plating thickness change point, while a second plating current corresponding to a second plating thickness is applied through plating current power sources of tanks after the plating thickness change point. To prevent arcing as the plating thickness change point passes through the apparatus, plating current application is suspended in the two tanks on either side of the plating thickness change point.

Abstract: A novel control unit for driving plural loopers provided with a tension constant automatically adjusting circuit in which a looper speed on its slave side is controlled such that a plurality of loopers having different amounts for moving the loopers and different strand numbers pass through the same % positions at the same time in order to control these plural loopers, and the number of times in operation for correcting an error of % position which takes place at the time of stopping transference of the plural loopers is minimized.

Abstract: A method of controlling the tension of a strip carried by a multitude of rollers disposed in four section of a furnace and driven by electric sources, one source for each section through respectives electric motors. The actual difference in tension of the strip between the inlet and outlet of each section is compared with a corresponding reference difference tension stored in a tension profile control circuit to form a tension deviation. An allotment-of-tension scheduling circuit successively receives all of actual tensions and sets a tension to each section and a correction factor. After having been amplified by the correction factor in one multiplier for each section, the tension deviation is applied to a speed regulator to control its associated allotted of tension and a tension profile within the furnace.