| 摘要 |
<p>A cylindrical casing contains a lower chamber filled with an elastic body e.g. a liquid, into which a linear piston protrudes whose top end operates the writing pen of a clockwork or electric driven drum type pen recorder in the upper half of the casing. The ambient pressure around the casing is translated by the elastic body into a linear displacement of the pen. Temp. compensation is provided by a mass of material within the chamber whose coefficient of expansion is less than that used for the walls of the chamber.</p> |
