Abstract: The window panes delimit a leak-tight air chamber and a narrow leak-tight space which can be filled with immiscible liquids having different optical indices supplied from a bottom reservoir and a top reservoir housed within the window frame. The top reservoir has decompression vents and the bottom reservoir is connected to a pump for injecting one of the fluids through a distribution chamber into the leak-tight space. The window serves to ensure heat insulation, to store and redistribute heat and to provide shielding against radioactive radiation.

Abstract: The invention relates to a security apparatus for detecting a fault such as a short circuit or ground fault in an electrical apparatus. Two similar but oppositely poled detection-and-safety circuits are coupled in parallel such that when one of said detectors energizes, the other does not. The invention also includes safety circuits having back-to-back Zener diodes so that spurious signals below a pre-selected level do not disturb the normal operations of the electrical apparatus being protected.

Abstract: The present invention relates to a security apparatus connected to the circuit of a machine in order to detect the presence of a fault therein such as a short circuit or loss of insulation between a power line and ground. The security apparatus comprises a tripping circuit having at least one transistor which is normally nonconductive and becomes conductive only when a fault current is fed to its base. The collector current activates a circuit breaking device and/or a signalling device which are continuously energized. The security apparatus operates, depending on its mode of connection, in response to a relatively small detected fault current resulting, for example, from defective insulation or from a short circuit. The security provided is irrespective of the state of the ground of the apparatus being protected.

Abstract: The invention relates to a safety electric connector. A conductive pin is slidably mounted within a socket. A sheath and a washer isolate the pin. Two further pins and the earth terminal are electrically connected to a plate which is connected to earth through a detection arrangement. Safety is assured even when the earth is not connected to the ground.The invention can be applied to the detection of an insulation fault and cutting off of power supply to a machine not connected to earth.