| 摘要 |
<p>The stand (1) has tubes, a foot (5) expanded and retracted relative to a main body (2), and an actuator including a brushless motor (6) with an output shaft (9). The actuator has an irreversible endless screw transmission for converting rotation of the shaft into linear displacement of the foot relative to the body and having a nut (14). The actuator has a programmable electronic control module (8) for controlling the motor and connected to the motor to control expansion and retraction of the stand to a preprogrammable length and to stop the motor when the length is attained. The nut is made of synthetic material i.e. polyacetal. An independent claim is also included for a method for utilizing a variable length support stand.</p> |
