Abstract: A computer controlled animation projection system is described. The system permits the projection of animated images onto a three dimensional projection surface, whether or not the surface is originally designed as a projection surface. The system comprises an animation source that can be edited using a processing means, a projection means, and an interface for coupling the animation source to the projection means. In operation of the present invention, a projection surface is selected, and an animation sequence is projected onto the projection surface. Portions of the projection surface upon which no image is to be projected are identified. Using a paint program, the background or projected frame is edited to "black out" those regions of the projected image that are projected onto those identified portions. This is done while the image is still being projected, so that the changes are viewed as they are made.

Abstract: A self-contained air gap spark arrester assembly is disclosed which may be constructed and tested prior to its incorporation into a fail-safe surge arrester assembly. The air gap spark arrester assembly comprises a rivet shaped electrode, on which are concentrically mounted an insulating ring, a ring electrode, and an insulating spacer ring. These elements are arranged so as to provide an air gap between the two electrodes, aproximately equal to the thickness of the spacer ring and shielded from particulate contamination. Due to the placement of the assembly's electrodes, it is particularly well suited for combination with gas tube arresters in metal canisters. In one embodiment the canister is of cylindrical form and houses a fusible alloy spacer, a cylindrical gas discharge tube, and the air gap spark arrester assembly.

Abstract: A screw-in station protector assembly includes a carrier housing containing a shorting cage which is biased by a compression to urge the cage and gas tube arrester assembly outwardly. The gas tube assembly contained within the cage includes a two electrode gas tube and a sealed external back-up air gap protector. The screw-in-assembly is particularly adapted for retro-fitting/replacement of carbon block arresters without modification.

Abstract: A screw-in station protector assembly includes a carrier housing containing a shorting cage which is biased by a compression to urge the cage and gas tube arrester assembly outwardly. The gas tube assembly contained within the cage includes a two electrode gas tube and a sealed external back-up air gap protector. The screw-in assembly is particularly adapted for retro-fitting/replacement of carbon block arresters without modification.

Abstract: A screw-in station protector assembly includes a carrier housing containing a shorting cage which is biased by a compression to urge the cage and gas tube arrester assembly outwardly. The gas tube assembly contained within the cage includes a two electrode gas tube. The gas tube is within a jacket which forms a sealed external back-up air gap protector. The screw-in-assembly is particularly adapted for retro-fitting/replacement of carbon block arresters without modification.

Abstract: Laminar air gap devices include two overlapping conductive layers separated by a non-metallic insulating layer. The insulating layer is perforated to provide at least one air gap between the conductive layers. The devices are positioned between a line electrode and ground electrode of a gas filled surge arrester and resiliently retained thereon by conductive clips. Non-metallic fusible elements, preferably plastic, are interposed between the clip legs and the associated electrode. The fusible element may also be the insulating layer between the conductive layers.

Abstract: A highly reliable gas tube arrester capable of protecting both the input and output lines from an excess voltage appearing thereon, includes a hermetically sealed housing, having a plurality of electrodes affixed therein and spaced in a predetermined manner between themselves and the housing to provide a plurality of spark gaps. A breakdown of any one of the spark gaps will ionize a gas disposed within the housing providing a low impedance path between all of the electrodes to the housing which is normally connected to ground potential.

Abstract: A three element gas filled tubular surge arrester is disclosed. The arrester has a hollow cylindrical mid-section or centerbody defining a first cylindrical electrode, and a pair of rod-shaped line electrodes extending inwardly into and along the axis of the centerbody from respective end caps to define respective annular gaps relative to the centerbody electrode as well as a gap between the opposed ends of the line electrodes. The end caps are electrically and mechanically connected to the line electrodes but insulated by annular insulator spacers from the centerbody. One of the line electrodes is partially hollow and apertured, and incorporates a pinch tube for exhaustion and subsequent filling of the tube interior with an ionizable gas.Incorporated in this known design is an annular sleeve which lines the centerbody and is coaxial relative to the rod electrodes. The sleeve, which is of metallic composition, functions to improve the overload handling capacity of the arrester.