Patent ID: 6479774
Filing Date: 2002-11-12
Classification: H01H

Abstract:
An operating mechanism for a circuit breaker having a contact arm having a movable contact and an associated fixed contact, said operating mechanism comprising:a movable handle yoke; a mechanism spring extending in tension from said handle yoke to a pin; a lower link extending from said pin to a crank operably connected to said contact arm, said crank positionable in an open position and a closed position, said crank being in said open position when said movable contact is separated from the associated fixed contact, said crank being in said closed position when said movable contact is mated to said associated fixed contact; an interface formed on said crank; a blocking prop having a first surface that engages said interface, said first surface preventing said crank from rotating towards said closed position; an upper link having a bearing at a lower end limiting movement of said pin; and a cradle, said upper link attached to said cradle at a rivet pin at an upper end, said cradle and upper link configured to allow limited range of rotation with respect to one another on said rivet pin, said upper link being at a first extreme of the limited range of rotation when the handle yoke is in an off position and said upper link is at a second extreme of the limited range of rotation when the handle yoke is fully in the on position, and said blocking prop configured to prevent said crank from rotating to the closed position until said mechanism spring exerts a predetermined moment on said upper link tending to cause said upper link to rotate from said first extreme to said second extreme.