| 摘要 |
PROBLEM TO BE SOLVED: To improve the characteristics of a linear induction motor driving an elevator cage door by changing a magnetizing current to a linear motor in response to the load of linear motor. SOLUTION: A magnetizing current level is set to a high value during door opening operation. During door closing operation, the magnetizing current level is set to a medium value. And by the signal from a first positioning system 42, if a door is completely placed at a door closing position by software through a feedback system, then the magnetizing current level is set to a low level. When a force is being applied to keep an elevator cage door opening, the first positioning system 42 detects this situation, this information is sent to a controller 60 through a first cable 68, and magnetizing current level is increased to a high value thereafter. By optimizing the magnetization current, the temperature rise in a motor can be reduced considerably. |
