US 12,255,441 B1
Mechanism for racking in and ensuring against over racking in and still allowing racking out of circuit breaker with respect to enclosure
Bruce Hack, Yonkers, NY (US)
Assigned to National Breaker Services, LLC, Middlebury, CT (US)
Filed by National Breaker Services LLC, Middlebury, CT (US)
Filed on Nov. 14, 2022, as Appl. No. 17/986,495.
Int. Cl. F16H 25/20 (2006.01); H02B 1/36 (2006.01)
CPC H02B 1/36 (2013.01) [F16H 25/20 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A circuit breaker racking in and out mechanism for a switchgear having an enclosure and a circuit breaker rackable therein and capable of racking out of said enclosure, wherein said racking in and out mechanism allows for initial racking in, limiting racking in until a desired rearward limiting position within said enclosure is reached by said circuit breaker, and racking out said circuit breaker with respect to said enclosure, said circuit breaker racking in and out mechanism comprising:
a) a screw rod with external threads, rotatively held by said circuit breaker and extending longitudinally within said enclosure;
b) a receiver nut with internal screw threads mating with said external threads of said screw rod, said receiver nut being held in a fixed position with respect to said enclosure to allow for a first direction of rotation of said screw rod with said external threads in engagement with said internal threads of said receiver nut to result in racking in, i.e., axial rotation of said screw rod in said first direction of rotation results in longitudinal racking in motion of said circuit breaker with respect to said enclosure;
c) a rearward-limiting, racking in-mechanism for said axial longitudinal motion of said circuit breaker with respect to said enclosure, comprising mechanical means for releasing said receiver nut to allow it to switch from said fixed position with respect to said enclosure to relative rotation with respect to said enclosure so as to allow said receiver nut to rotate when said screw rod is further rotated in said first direction of rotation so that said screw rod and said receiver nut rotate together and no further longitudinal motion of said circuit breaker with respect to said enclosure continues, even when said screw rod is further rotated in said first direction of rotation, commencing when said circuit breaker reaches a desired rearward limit position within said enclosure; and
d) said screw rod and said receiver nut being held in threaded engagement for each of the steps of racking in, limiting racking in and initial racking out said circuit breaker with respect to said enclosure wherein said receiver nut is blocked from rotation in said first direction of rotation and a second direction of opposite rotation but released from being blocked from rotation when said desired rearward limit position of said circuit breaker within said enclosure is reached.