Abstract: The invention has especial utility for providing completely safe hermetic sealing of actuators extending into highly sensitive or isolative process equipment, such as that using atomic radiation. The invention uses a general principle taught by the inventor's prior U.S. Pat. No. 3,933,052. The actuator is hermetically sealed by the aid of a flexible diaphragm, and the diaphragm is made safe by pressure compensation. A sealing liquid confined on the outside of the hermetic diaphragm applies the same pressure to the outside face of the diaphragm as is applied by the process atmosphere to the inside face of the diaphragm. According to the embodiment illustrated in that patent, a diaphragm (actually a bellows) entirely separate from the actuator was exposed to the process atmosphere to apply its pressure to the sealing liquid.
Abstract: A pressure compensated, hermetically sealed transmission system is described which includes, basically, a hermetic rotary coupling. Rotary motion is applied through a casing, wherein a cylindrically shaped input shaft having a circular inner bearing race affixed to one end is coupled to a generally spherical shaped wobble plate by means of roller or ball bearings. In similar fashion, an output shaft is similarly coupled to the spherical shaped wobble plate at the opposite end. The inner races of the shafts are positioned at an angle and located eccentrically from the respective shaft center line. Both shafts are supported at their outer ends by combination journal thrust bearings, which are coupled to the main casing. The wobble plate is prevented from rotating about the common axis of the two shafts. Thus, as one shaft rotates, the wobble plate rocks, due to .[.ball.]. bearing action, but does not rotate. Likewise, due to the bearing action, as the wobble plate rocks the output shaft rotates.