Abstract: A fuse cutout switch (12) attached to electrical distribution equipment mounted on poles of electrical distribution systems operable with hooksticks (16) in which a connection assembly (28) detachably engages a first distal end of a fuse body (20) that is pivotably and detachably engaged at a second distal end to a hinge (22). A grab member (32) attached to the fuse body (20) near the first distal end includes a receptacle (36) for selectively receiving the hookstick (16) for disengaging the fuse body (20) from the connection assembly (28). A restoring member (40) attached to the fuse body (20) near a second distal end has a receptacle (42) for selectively receiving the hookstick (16) for pivoting the fuse body (20) about the hinge (22) and engaging the fuse body (20) to the connection assembly (28). Various embodiments of the grab member and the restoring member are disclosed, together with methods of modifying existing fuse cutout switches and of operating a fuse cutout switch.

Abstract: A fusible element is provided that includes cooperating interfitting parts surrounded by fusible material. The cooperating interfitting parts are arranged so as to place compressive force on the fusible material in response to attempted separation of the interfitting parts. Further, the arrangement also reduces the forces on the fusible material. In response to a predetermined time-current condition, the fusible material softens sufficiently to permit the release and separation of the interfitting parts.

Abstract: A fuse cutout assembly (21) including a containment housing (22), a fuse (23), a mounting assembly (24) mounting the fuse (23) in the housing (22) for electrical connection to an electrical circuit. A plunger assembly (29) is movably mounted at least partially inside the housing (22) and preferably surrounding the fuse (23). An electrical conductor (28) is electrically connected to the fuse (23) and mechanically connected to the plunger assembly (29). The plunger assembly (29) is supported in the housing (22) in a first position and is formed to be propelled inside the housing (22) away from the first position to a second position by the hot gases generated upon rapid melting of the fuse (23). Movement of the plunger assembly (29) is preferably yieldably resisted by the air trapped between the plunger assembly (29) and the housing (22), which may be vented during plunger movement.

Abstract: An electrical fault protective device for providing power interruption in electrical circuits rated up to 10,000 amperes and above. The device comprises a single- or double-vented expulsion-type fuse, connected at one vented end to a hollow bus and at the other end to a conductive expansion chamber for a double-vent fuse or an electrical contact for a single-vent fuse. A spring located in the hollow bus is attached to the fusible link for pulling the fusible link from the fuse tube to rapidly extinguish the arc when the fuse blows. The fuse tube is also retractable into the hollow bus when the fuse blows to provide a visual indication of fuse operation and to relieve the dielectric stress on the fuse tube.

Abstract: An ejecta trap for a drop out expulsion fuse of the type comprising an elongate insulating body with a conductive head fitting and tail socket. The tail socket is pivotally connected to the tail fitting and the head and tail fittings are adapted to electrically and mechanically engage respective head and tail terminals. A fuse means is connected within the body between the head and tail fittings. The ejecta trap is pivotally mounted on the tail terminal such that it may be swung between an in-use position immediately below the tail fitting where it collects ejected fuse means material and another position.

Abstract: A circuit breaker characterized by a voltage-responsive device having an electromagnet including an armature. A linkage connects the armature to the trip latch of the circuit breaker in order to open the circuit breaker contacts when a voltage occurs that is less than a predetermined voltage value. Under normal operating conditions, when the contacts are closed, the armature is retained in place by an electromagnetic force, but is biased away therefrom when the voltage drops below that voltage value.

Abstract: This invention relates to electric fuses meeting the requirements of Underwriter's RK1 classification. It includes a high-current interrupter in the form of a fusible element having serially arranged points of reduced cross-section and a low-current interrupter in the form of a plunger soldered to the high-current interrupter. The plunger is spring biased, and when the solder joint softens, the plunger separates under the action of the spring from the fusible element leaving a large gap between them. The separation of the plunger from the fusible element is allowed to be particularly large on account of the fact that the plunger may be allowed to move into a special fuse cap, known as a cap having a rejection feature as described, for instance, in U.S. Pat. No. 2,943,295 to V. N. Stewart; June 28 1960 for REJECTION TYPE FUSE CLIP and in many other patents.

Abstract: A high voltage dropout type expulsion fuse has a lower trunnion assembly mounted on one end and a fuse release assembly mounted on the other end thereof. To assure the proper positional relationship between the trunnion assembly and the fuse release assembly, the fuse housing has a locating boss at one end adapted to engage and position the trunnion assembly and a positioning slot formed in the other end adapted to engage and position the fuse release assembly. The locating slot and boss must be properly positioned with respect to one another to assure the proper positional relationship of the trunnion assembly and the fuse release assembly. The lower locating boss is integrally formed on the wall of a metallic ferrule by extruding a portion of the wall into the cavity of a die to form an integral locating boss. This integral boss cannot cause the leakage of moisture into the interior of the fuse.

Abstract: Load-break switches and current-limiting fuses are often serially connected and placed one above the other. This arrangement is relatively bulky, and involves in particular relatively large requirements in respect to height.The present invention concerns an arrangement of parts wherein the load-break disconnect and the current-limiting fuse are electrically connected in series, but wherein they are arranged spatially in parallel, substantially in coaxial relation, the load-break switch or some of its constituent parts being arranged inside of the current-limiting fuse; or the load-break switch and the current-limiting fuse may be provided with contact means common to both of them.