The spring Drive feature null electricity breech operating mechanism for the breech operating mechanism

摘要

PROBLEM TO BE SOLVED: To avoid any danger of a mechanism malfunctioning, in a switching device and a circuit breaker in particular. ;SOLUTION: This mechanism has an engagement shaft 11 rotatable around an axis, a big gear 13 attached to the shaft, a small gear 19 engaged with the big gear to apply a force to the engagement spring and a means for preventing the big gear and the small gear from being locked each other after the shaft is released. This means is dependent on a tooth shape of the small gear 19 and a tooth shape of the big gear 13. The tooth of the big gear has the first gap in which the first retractable tooth is placed continuously in a rotation direction. After this tooth, the second gap extending for a length a little longer than integral pieces of steps follows. A tooth right after the second gap is the second retractable tooth which can retreat along the axis against energisation by the spring. The each retractable tooth and the each first tooth impossible to be retractable following after the last retractable tooth crosses a common edge outside in the diameter direction, and has a flank including an inclined surface in a top area adjacent to the edge.;COPYRIGHT: (C)1999,JPO