Spring-powered operator for a power circuit breaker

A method of controlling a circuit breaker having an opening mechanism which is charged when the breaker closes and which when allowed to discharge opens the circuit breaker, said method of controlling the circuit breaker comprising:

• providing an opening mechanism;
• coupling a lever with the circuit breaker's opening mechanism;
• constraining the lever to move between an open position at which the circuit breaker is open and a closed position at which the circuit breaker is closed;
• providing a first charge command when the lever is at its open position;
• providing a rotatively mounted crank coupled to the circuit breaker and a rod having a first end rotatively coupled to the crank and a second end distal the crank which is constrained to reciprocating motion by the crank along an axis generally perpendicular to the crank rotational axis;
• in response to said first charge command, charging an energy storing spring captured by the rod having a charged position at which it stores energy when the crank is at a top dead center position and releasing stored energy when allowed to discharge at a bottom dead center position of the crank, and latching the spring at a charged position;
• providing a discharge command at a time when the spring is at its latched position;
• in response to said discharge command, unlatching the spring and allowing it to discharge in response to said discharge command;
• utilizing energy released by the discharging spring to rotate a cam through a path in which the cam engages the lever and moves it from its open to its closed position to thereby close the circuit breaker, and latching the lever at its closed position to thereby keep the circuit breaker closed;
• in response to the discharging of the spring, providing a second charge command and, in response to the second charge command, again charging the energy storing spring and latching it in its charged position;
• and
• providing a trip signal at a time when the breaker is closed and, in response thereto, unlatching the lever from its latched position to thereby allow the circuit breaker to open and the lever to move to its open position.

A spring-powered operator for controlling a circuit breaker having an opening mechanism which is charged when the breaker closes and which when allowed to discharge opens the circuit breaker, said operator comprising:

• an opening mechanism;
• a lever mounted for pivoting about a pivot axis and coupled with the circuit breaker's opening mechanism to pivot about said axis between an open position at which the circuit breaker is open and a closed position at which the circuit breaker is closed;
• an energy storing spring having a charged position at which it stores energy and releasing stored energy when allowed to discharge;
• a source selectively providing a first charge command when the lever is at its open position, a discharge command when the spring is at its charged position, and a trip command when the circuit breaker is closed, and providing a second charge command in response a discharge of the spring;
• p1 a charging mechanism coupled with the spring and the source and responsive to each of said first and second charge commands to charge the spring, said charging mechanism comprising an electric motor, and eccentric shaft rotated by the motor, a connecting rod reciprocated by said eccentric shaft, a drive pawl drive by said reciprocating connecting rod, a splined shaft and a ratchet wheel rotated about the shaft axis by said pawl to rotate said shaft, a rotary crank splined on said shaft, said crank being coupled with said spring to compress the spring in moving toward a top dead center position of the crank, and a close latch operative at a position past and adjacent to the top dead center position of the crank to prevent further rotation of the crank about the shaft axis under the influence of the spring until the source provides said discharge signal;
• a discharging mechanism coupled with the spring and the source and responsive to the discharge command to unlatch said latch and permit the spring to discharge;
• and
• a lever driving mechanism coupled with the spring and driven by the discharge thereof to drive the lever to and maintain it at its closed position, thereby closing the circuit breaker and maintaining it closed, said lever driving mechanism comprising a rotary cam splined to said shaft to rotate therewith when the discharging spring rotates the crank to move it toward a bottom dead position, said cam having a cam face engaging said lever in the course of the spring's discharge to pivot the lever to its closed position;
• and
• a trip mechanism responsive to said tip signal to release the lever from its closed position and allow the circuit breaker to open.