William W Shubin

US Patent:

6715586, Apr 6, 2004

Filed:

Apr 22, 2002

Appl. No.:

10/128906

Inventors:

William A. Shubin - Fullerton CA 92835

International Classification:

B66B 1314

US Classification:

187316, 49 26

Abstract:

A method for upgrading an elevator control circuit having a phase , alternate and phase input circuits, includes placing a first impedance of a switching device across a door motor armature of the elevator control circuit for enabling a selected door closure speed, and placing a second impedance of the switching device in series with a door motor field of the elevator control circuit for enabling a selected door operating torque. The method further provides a logic circuit enabling the impedances when an input signal is present at, at least one of, the phase and the alternate input circuits; and disabling the impedances when an input signal is present at the phase input circuit.