The brookfield NB-5000 Vertical Lift Industrial Operator has been designed, tested and is being manufactured by brookfield industries, inc. and complies with UL 325.
The NB 5000 will vertically raise and lower any industrial lead doors or heavy access panels weighing up to 2000 lbs. The maximum travel distance is 24" in one direction at a rate of 49 inches/min. This is accomplished with a 1 HP variable speed AC Brakemotor coupled to a helical in-line first stage (2.24:1) gear reduction. A second stage 6:1 worm gear reduction joins a 1 _" diameter machine screw jack to complete the drive train. Door activation is via a (3) position-keyed switch. Safety features include the following: a maintained contact open and close keyed switch that is spring return to stop in both directions; end of travel limit switches (supplied) that will override the keyed switch when activated; adjustable forward and reverse current limit trimpots that allow the stall torque to be safely set slightly above the operating forces, which protects equipment as well as providing for another degree of safety. The motor control, power supply hookup and low voltage limit switch hookup is housed in a NEMA 1enclosure. Manual operation during power interruption is accomplished by releasing the brake lever at the rear of the motor. Turning the input shaft of the screw jack in the proper direction will either raise or lower the door.
Custom designs can be provided for varying weights, travel distances and travel rates.
Guide system: Door to be guided in 2 directions by attaching 6 UHMV Polyethylene strips to the door.
Unit of Measure

Door Wt 1

N/A 2000 lbs.

Rated Linear Speed (max.)

N/A .82 in./sec.

Travel (max. in one direction)

N/A 24.5 in.