Patent ID: 7931128
Filing Date: 2011-04-26
Classification: B66B

Abstract:
1. An elevator device, comprising: drive means including a drive sheave, a motor for rotating the drive sheave, and a motor driving portion for driving the motor; suspension means looped around the drive sheave; a car and a counterweight that are suspended by the suspension means to be raised/lowered by the drive means; and control means for controlling the motor driving portion, wherein the control means monitors a load on at least one component of the drive sheave, the motor for rotating the drive sheave, and the motor driving portion for driving the motor within the drive means, by monitoring at least one of a current, a temperature, a power, a switching duty, or a motor voltage of the at least one component while that at least one component is operating and while the car is running, generates a control command regarding a running speed of the car on a real-time basis in accordance with a state of the load, and outputs the control command to the motor driving portion, wherein (i) the control means continuously raises the running speed of the car after the car has started running, until the running speed of the car reaches an upper limit that is prescribed when the car starts running, and holds the running speed of the car at the upper limit to make a shift to constant-speed running unless the load monitored while the at least one component is operating and while the car is running reaches a preset threshold, and (ii) when the load monitored while the at least one component is operating and while the car is running reaches the preset threshold before the running speed of the car reaches the upper limit, the control means shifts to a constant-speed running at a speed lower than the upper limit.