| 摘要 |
PURPOSE:To make constitution simple and production easy and to obviate inclusion of nonlinear errors by cnstituting a pen driving mechanism of a balance beam in which moment is generated by an input signal and nozzle back pressure, a driving bellows which makes linear motion, a feedback spring, etc. CONSTITUTION:When input pressure Pi is inputted to an input bellows 21, the clockwise moment around a fulcrum 33 is generated in a balance beam 31, and the clearance between a flapper part 34 and a nozzle 42 is decreased by this moment, whereby the nozzle back pressure is increased. A feedback spring 61 is compressed via a bellows 52 by said back pressure, and the moment balancing with the moment generated by the pressure Pi is applied to the beam 31. The displacement of the driving bellows 52 is drawn out dasily to outside by a rod 56. Since no pivots and the like are used, the construction is simple, the manufacture is easy and no nonlinear error are contained. |
