×

Method of driving door of automatic door assembly

  • US 4,090,113 A
  • Filed: 06/10/1976
  • Issued: 05/16/1978
  • Est. Priority Date: 06/10/1975
  • Status: Expired due to Term
First Claim
Patent Images

1. A method of driving an electric door motor of an automatic door assembly, comprising the steps of:

  • (a) driving the motor by at least a normal operating voltage during an initial period of the stroke of the door;

    (b) reducing said voltage to a level below said normal operating voltage after the lapse of said initial period of the door stroke to reduce the moving-force applied to the door;

    (c) restoring and maintaining at least the normal operating voltage for the time needed to drive the door to the end of its stroke; and

    (d) thereafter, removing said voltage.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×