GB836392A - Improvements in and relating to electrical capacitors - Google Patents

Abstract

836,392. Folding paper. PLESSEY CO. Ltd. June 6, 1956 [April 5, 1955], No. 9925/55. Class 100(1) [Also in Group XXXVI] In a process for making an electrolytic capacitor, conducting strips from reels 34 and 36 are assembled with porous paper strips from reels 42 and 43, the composite strip thereafter being folded in a zig-zag fashion by a mechanism 21 shown in greater detail in Fig. 4 and then carried forward by combs 80, 81 fitting within the folds in the strip to mechanism 24 where the composite strip is cut into suitable lengths. The strip from reel 34 preferably comprises cotton gauze which has been sprayed with aluminium on both sides to form a porous metallic surface, while the strip from reel 46 comprises an etched aluminium foil. The folding mechanism 21 comprises a pair of rollers 52, 53 through which the composite strip is led. These rollers are actuated by a cam-mechanism 56 whereby they are moved together in a reciprocating motion in a vertical direction; simultaneously the cam mechanism controls bifurcated guide members 60, 61 which move both horizontally and vertically in synchronism with the rollers 52, 53 so that the composite strip passing between the rollers is folded alternately in opposite directions. Thus from the position shown, member 61 rises to mesh with member 60, then the rollers descend to fold the strip about one prong of the member 61, member 60 subsequently moving upwards and when clear of member 61 to the left and then down again to engage once more with member 61. The rollers then move upwards to form a further fold and so the process continues with upper and lower folds being formed alternately. The folded strip issuing from the mechanism 21 is carried forward by combs 80, 81 which are actuated by the cam mechanism 83 shown in greater detail in Fig. 5, so that they rise alternately and engage the folds of the strip and then move in the forward direction carrying the strip forward. A cam-operated blade 99 is periodically inserted in the path of the strip to compress the folds as they leave the combs 80, 81; then when the blade is withdrawn the compressed strip passes down the channel 22. As it emerges from the channel it is cut into suitable lengths by cutting mechanism 24. Electrolyte is discharged on to the strip from the pipes 92 and 102. It is stated that the folding process may be arranged so that periodically a larger fold may be made. Such a fold may be used to mark the end of a section or to facilitate making connection to an electrode of the capacitor. Specification 833,984 is referred to in the Provisional Specification.