Easy opening door control device
AssigneeThomas Industries, Inc.
InventorJames A. O'Brien, II
Life of this patent
Estimating the term…
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.
Claims20
A door control device for use with a pivotable door and powered by an external electrical power supply comprising:
- a rotatable spindle member for engagement with the door to rotate when said door is pivoted;
- energy storage means operatively connected to said spindle member for releasing energy to close said door;
- an electrical motor;
- selective transmission means between said motor, energy storage means and spindle member, operable during an opening of said door, for causing energy transmission from said motor to said energy storage means, yet preventing energy transmission from said motor to said spindle member, and for disconnecting said spindle member from said energy storage means;
- and
- circuit means for connecting said external electrical power supply to said motor to assist in said opening of said door.
A door control device for use with a pivotable door and powered by an external electrical power supply comprising:
- a rotatable spindle member for engagement with the door to rotate when said door is pivoted;
- compressible spring means operatively connected to said spindle member for releasing energy to close said door;
- a d.c. motor/generator having a rotor shaft;
- a one-way clutch mechanism arranged between said spindle member and said rotor shaft for preventing transmission of rotary motion to said rotor shaft in a first rotary direction of said spindle member and for causing transmission of rotary motion to said rotor shaft in a second rotary direction of said spindle member;
- selective transmission means between said motor/generator, spring and spindle member, operable during an opening of said door, for causing energy transmission from said motor/generator to said spring, yet preventing energy transmission from said motor/generator to said spindle member, and for disconnecting said spindle member from said energy storage means;
- circuit means for connecting said external electrical power supply to said motor to assist in said opening of said door and for connecting an electrical output of said dc motor/generator to an electrical input for said motor/generator such that electrical energy provided to said input from said output will retard rotation of said rotor shaft and spindle upon a closing of said door.
A door control device for use with a pivotable door and powered by an external electrical power supply comprising:
- a housing member;
- a spindle member rotatably carried in said housing and having a portion extending beyond said housing for engagement with the door to rotate when said door is pivoted;
- a cam member carried on said spindle to rotate with said spindle;
- a cam plate member mounted for longitudinal movement in said housing and engageable by said cam member whereby rotational movement of said cam member effects longitudinal movement of said cam plate;
- a extension arm secured to said cam plate to move therewith;
- a rack gear on said extension arm;
- a stationary pinion gear engageable with said rack gear whereby longitudinal movement of said rack gear results in rotational movement of said pinion gear;
- a d.c. motor/generator having a rotatable rotor shaft mounted in said housing;
- a gear train positioned between said pinion gear and said rotor shaft to transmit rotary motion from said pinion gear to said rotor shaft;
- a one-way clutch mechanism positioned between said pinion gear and said rotor shaft to prevent transmission of rotary motion to said rotor shaft in a first rotary direction of said pinion gear and for causing transmission of rotary motion to said rotor shaft in a second rotary direction of said pinion gear;
- and
- an electrical circuit connecting said external electrical power to said motor/generator during an opening movement of said door to cause a rotation of said pinion gear, a longitudinal movement of said arm and cam plate resulting in compression of said spring and movement of said cam plate away from said cam and, during a closing movement of said door, connecting an electrical output of said motor/generator to an electrical input for said motor/generator such that electrical energy provided to said input from said output will retard rotation of said rotor shaft and spindle;
- an adjustable resistance device in said circuit to adjust the amount of electrical energy transmitted from said output to said input;
- and
- a switch in said circuit means engaged by said cam plate to effect a two speed control for the closing of the door.
Dependencies are inferred from the claim text.