Switchgear operating mechanism

An operating mechanism for a switchgear unit is disclosed. The operating unit includes an input drive shaft operable to rotate and counter-rotate. A trip linkage has a cam disk rotatably coupled to the input drive shaft and is coupled to a spring-drive mechanism for opening and closing the vacuum interrupter. An over-center linkage has a drive link rotatably coupled to the input drive shaft, and a follower link for opening and closing the isolating disconnect. Rotation of the input drive shaft through a first range drives the trip linkage for opening the vacuum interrupter and moves the drive link though an over-center position without opening the isolating disconnect. Rotation of the input drive shaft though a second range drives the over-center linkage for opening the isolating disconnect after the vacuum interrupter is opened.