Otis Elevator Company

Yuji Kanzaki

Koji Yamada

Toshimitsu Mori

Tadaaki Nabetani

David Wayne Jones

Hiroaki Tateno

Yasuhisa Shioda

Shusaku Shibasaki

An elevator system (,) includes an elevator car (,) supported for vertical movement on a belt (,) having an end fixed to the hoistway (,) and the other end wound about a drum (,) of a drum drive (,). When the belt (,) is wound or unwound about the drum (,), the elevator car (,) is raised or lowered, respectively.

Drum drive elevator using flat belt

An analog DC link bus voltage in an induction motor drive is converted to a digital DC link bus voltage so that if the DC link bus voltage exceeds an ON voltage threshold of a switch and this condition exists a holding time later, the switch closes, thereby allowing regenerated power in the DC link to be dissipated in a resistor connected across the DC link. And if the DC link bus voltage falls below an OFF voltage threshold and that condition exists a latching time later, the switch is opened so that no regenerated power may be dissipated through the resistor.

Method for consuming regenerated power for elevators

Growing community of inventors

Kawasaki, Japan

Yuji Kanzaki