| 摘要 |
PURPOSE:To obtain a titled mechanism which is small-sized and light, and is capable of absorbing sufficiently the influence of a load variation by a zoom operating speed, by leading in a servo-driving system which exerts no influence on the zoom operating speed, and making this servo-driving system absorb the load variation. CONSTITUTION:A cam ring 12 is turn-driven by pushing and pulling an operating rod 1, and in that case, voltage being proportional to this turning speed is generated from a tachometer generator T, voltage being proportional to it is applied to a motor M through an operational amplifier, and the motor M executes servo-driving driven by turning of the cam ring 12 by the operating rod 1. A potentiometer P is provided as a position detecting means for detecting a turning position of the cam ring 12, and a converting means for converting the output voltage of the potentiometer P to an output corresponding to a load variation characteristic in case of the zoom operation of the cam ring 12 is provided, an output of this converting means is inputted to the servo-driving system, and the load variation characteristic in case of the zoom operation is cancelled. |
