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Door control apparatus

  • US 4,490,624 A
  • Filed: 05/31/1983
  • Issued: 12/25/1984
  • Est. Priority Date: 06/02/1982
  • Status: Expired due to Fees
First Claim
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1. Door operating means of the kind comprising an electric motor connectable to a mains power supply and a drive assembly operable by that motor to open and close a door characterised in that said operating means further comprise a second electric motor, an automatic clutch which when engaged, connects the second electric motor to enable it to operate the drive assembly to open the door, a second power supply, and means responsive to interruption of the mains power supply to energise the second electric motor from the second power supply and to engage the clutch.

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