A temp. dependent actuator for positioning or switching applications consists of a closed system contg. a temp. sensor (10), a flexible capsule (20) and a capillary tube (11) connected to it. It is simplified in construction and design compared to conventional arrangements using liquid media. This enables the actuator to be relatively simple and economical to produce. The system is filled with a gas whose pressure at room temp. exceeds atmospheric pressure. Its absolute pressure lies between 100 and 1500 KPa, pref. between 110 and 400 KPa, and if possible between 150 and 225 KPa. A monatomic, pref. inert, gas is used, e.g. Argon, Heluim, Neon or Krypton. This ensures that the gas is non-corrosive. The dead vol. of capillary tube (11) and capsule (20) constitute no more than 30 % of the total system vol.
|Publication status||Published - 6 Mar 1981|