Automatic self-compensating layer capacitor trimming equipment - cuts sections from continuous reel, measures capacitance, compares with reference and adjusts successive cuts under microprocessor control

摘要

The stack layer capacitors are cut from a rectangular strip (1) by a circular saw (5). The capacitor strip is pre-fabricated with edge terminations completed. The strip is fed through rolled onto a stop-block (3) which allows a certain length (l) of capacitor to be severed. A manual screw jack (6) allows the length to be set approximately. After a section has been cut, a pair of electrical probes (7) attached to an articulated jaw clasps it and a measurement of the capacitance of the section is made by a capacitor bridge apparatus (9). The value of capacitance, relative to the value of a standard reference, generates a proportional signal in a micro-processor controlled circuit (10). A command signal to the articulated mechanism motor (13) causes the capacitor to be ejected into appropriate bins. A difference signal of either polarity is fed to a step-motor (11) which drives a cam wheel (12) which raises or lowers the stop bar (3). A variation in capacitance allowing a control to within 10% tolerance is attainable with the equipment.