Easy opening door control device
US5193647A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 23, 1992 |
| Grant date | Mar 16, 1993 |
| Priority date | — |
| Expiry date | Mar 23, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T74/18808
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A device for controlling swinging doors utilizing an externally powered motor to compress a spring during door opening to store energy in the spring. The motor is not used to open the door, but only to compress the spring, thereby utilizing a minimum amount of electrical energy and allowing for a very easy opening of the door. The motor acts as a generator during the closing of the door with generated electrical energy fed back to the motor to retard rotation of the rotor, providing a brake on the closing movement of the door. The feedback circuitry includes a switch for varying the braking during the final degrees of closing movement as well as a variable setting device allowing control of braking force.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.