Defeatable interlock for fuse access door
AssigneeGeneral Electric Company
InventorsBenjamin A. Piteo, Jr., Frederick D. Kaufhold
Life of this patent
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Abstract
A fuse access door of a fusible switch enclosure is held closed by a latch slidably mounted thereto. A resilient interlock actuator secured to the door cooperates with a defeatable switch interlock arm to enable switch closure only while the door is closed and to interlock the latch against unlatching movement while the switch is closed. However, depression of the interlock arm via the interlock actuator defeats this interlock to permit access to the fuses while the switch is closed.
Claims8
A defeatable interlock for an access door to an electrical enclosure containing a switching device having a manual operating handle connected with the switch operating mechanism and protruding through an opening in the enclosure to facilitate articulation of the operating mechanism between its switch open and switch closed conditions, said defeatable interlock comprising, in combination:
- A. a latch mounted to the rear side of the access door for movement between a latching position and an unlatching position;
- B. a latch handle connected with said latch and disposed on the front side of the access door to accommodate manual movement of said latch between its latching and unlatching position;
- C. a resilient interlock actuator mounted to the rear side of the access door in perpendicular relation to the path of movement of said latch between its latching and unlatching positions, said interlock actuator having a rearwardly deflectable free end portion;
- D. an interlock arm coupled with the switch operating mechanism for movement between an ON position and an OFF position in concert with the articulation of the switch operating mechanism between its closed and open conditions, respectively, in its ON condition, said interlock arm interfering with movement of said latch from its latching position to its unlatching position thereby preventing opening of the access door with the switch operating mechanism in its closed condition, said interlock arm in its OFF position being controlled by said interlock actuator to prevent articulation of the switch operating mechanism to its closed condition while the access door is open;
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- E. means forming an interlock defeat slot in the access door accommodating the insertion of a tool effective to rearwardly deflect said free end portion of said interlock actuator, said deflected actuator free end portion engageably moving said interlock arm in its ON position out of interfering relation with said latch, said latch then being moveable from its latching position to its unlatching position permitting opening of the access door with the switch operating mechanism in its closed condition.
Dependencies are inferred from the claim text.