Abstract: Apparatus and technique for providing series electrical connection between a conductor and an electrical component or unit in a rapid and automatic manner without the necessity for manual manipulation or preparation of the conductor. A pair of spaced walls are provided each containing a pair of wire-guiding slots through which a wire can be looped, with the loop end extending outside one of the walls. A pair of insulation displacement connectors is provided between the walls with wire receiving grooves in alignment with the slots in the spaced walls. A knife edge is provided between one of the walls and the connectors. A cover or other element is fitted over the walls and, during closure, causes the wire to be forced into the connector grooves to make electrical connection with the respective connectors, and also causes severing of the loop end of the wire by the knife edge, thereby to provide a series electrical connection.

Abstract: A snap-together, passive infrared detector assembly includes a modular passive infrared detector sub-assembly defining an optical cavity. In one embodiment, the passive infrared detector sub-assembly is slidably mounted to a resilient U-shaped housing sub-assembly suitable for high wall or ceiling flush mounting. (An aesthetic cover plate is snap-locked to the U-shaped housing.) In another embodiment, the passive detector sub-assembly is mounted in a plastic housing having an aperture for high wall or ceiling surface mounting. An optical window is snap-locked onto the mouth of the optical cavity in both embodiments. Both embodiments are self-contained and fashioned substantially of a plastic material. The modular passive infrared detector sub-assembly includes an optics and an electronics module. The optics module is composed of snap-together first and second plastic mirrored members having respective arcuate metalized surfaces which define the optical cavity.

Abstract: An optical smoke detector including a plurality of walls extending from a dark chamber in which an optical smoke sensor is located. The walls form passages in the detector which extend from smoke entrances on the outer perimeter to smoke ports that feed into the dark chamber. In construction, the smoke entrances extend substantially continuously around the perimeter of the smoke detector to allow the free entry of smoke into the dark chamber. Each wall is arranged to overlap the next so as to obstruct the direct rays of light from entering the dark chamber and a screen is disposed around the perimeter of the detector to prevent the entrance of insects into the dark chamber.