Servometer® – PMG, LLC introduces a new and unique "atherm" temperature sensitive bellows assembly. These lightweight, extremely sensitive assemblies are thin-walled, electrodeposited nickel bellows soldered to custom end pieces filled with a working fluid (with a known coefficient of thermal expansion) and then sealed.

By sealing a specific volume of fluid within a Servometer electrodeposited nickel bellows, the volumetric thermal expansion characteristic of the fluid is transformed into a precise, measurable linear movement. This movement can be used as an actuator, or calibrated to be read as control data, and is completely reversible due to the extremely low hysteresis of the bellows material.

A Servometer atherm is presently being used in one defense application to compensate for the thermal growth of components within precision targeting devices. The response of the bellows ensures that the targeting image is not distorted by environmental changes in temperature from sub-zero to extreme desert heat conditions.

These athermalization bellows assemblies are designed, manufactured and assembled to the customers exacting specifications.