Title: Trigger speed control switch with plastic pack semi-conductor

Abstract: A portable tool double-pole trigger switch enclosing a speed control circuit that includes a plastic pack SCR (semi-conductor controlled rectifier) of the sensitive gate type, a capacitor and a variable resistor. In a first version, the mounting tab of the SCR is soldered to a connector that is contacted by the resistor slider. A ceramic capacitor may be used by soldering its leads between the cathode and gate terminals of the SCR, the mounting tab serving as the anode terminal. A chip capacitor may be used by soldering it to bridge the cathode and gate terminals. In another version, the mounting tab may be arranged to be contacted directly by the resistor slider, thus eliminating the aforesaid connector.

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Inventors: Dummer, Merlin R. (Arab, AL, US)

Application Number: 486767
Filing Date: 1974-07-09
Publication_date: 1976-02-03
Assignee: Cutler-Hammer, Inc. (Milwaukee, WI)
Primary Class(es): 318/249 200/522
Other Classes:
US Patent Ref:

3439248	Apr, 1969	Winchester et al.	318/349.
3536973	Oct, 1970	Matthews et al.	318/345.
3775576	Nov, 1973	Brown	200/157.
3842328	Oct, 1974	Supel et al.	318/249.

Other Refs:
Primary Examiner: Schaefer, Robert K.
Assistant Examiner: Duncanson, Jr., W. E.
Attorney: Rather; H. R., Autio; Wm. A.