| 摘要 |
<p>A medium voltage electrical switching apparatus is disclosed having a switching compartment, first and second fixed contacts at spaced apart locations within the switching compartment, and a switching contact movable within the switching compartment between a first position connecting the fixed contacts and a second position in which the connection is broken. A drive shaft (502) is provided for effecting movement of the switching contact in either sense between its two positions. A locking means (517, 518, 519) locks the drive shaft (502) against rotation when the switching contact is in the first or second position, and lock releasing means responsive to torque applied to the drive shaft (502) releases the locking means when the applied torque reaches a certain minimum value so as to allow the shaft (502) to drive the switching contact from one position to the other. Coupling means (511) allows torque to be applied to the drive shaft (502) from externally of the switching compartment.</p> |
