Abstract: A pressure chamber assembly for retaining a fluid includes first and second relatively separable casings defining an enclosed chamber and a fluid leak path extending from the chamber to an exterior region. An inner seal member is disposed along the leak path to restrict flow of fluid from the chamber to the exterior region. An outer seal member is disposed along the leak path between the inner seal member and the exterior region to restrict flow of fluid from the chamber to the exterior region. The inner seal member is a cup seal.

Abstract: A linear operating mechanism for a slotted optical switch 10 which produces a guaranteed OFF-point for a consistent linear displacement of a switch operator 58 with respect to a reference surface 66 of the device enclosure 62. The guaranteed OFF-point is consistently repeatable from one device to another. The device enclosure 62 defines an integrally formed support for receiving an emitter 14 and a receiver 18 of the slotted optical switch 10. The enclosure 62 further defines a fixed Off-plane 114 immediately adjacent the receiver 18 and precisely located with respect to a reference surface 66 on an outside surface of the enclosure 62. The switch operator 58 is received within the optical switch slot and has a distal end 86 extending outside the enclosure 62 a precise distance with respect to the reference surface 66 when the operator is in a normally biased first position.