Automatic circuit breaker pan interlock

An apparatus for use with a circuit breaker, a cell pan configured to support the circuit breaker in a switchgear cell, and rollers supporting the circuit breaker on the cell pan for horizontal draw-out movement outward from the cell pan, the apparatus comprising:

• a lift pan configured to carry the circuit breaker outside of the switchgear cell, the lift pan having a track for a roller on the circuit breaker;
• an extension rail configured to interconnect the lift pan with the cell pan in an aligned position for the track to receive the roller upon horizontal draw-out movement of the circuit breaker from the cell pan;
• and
• a latch supported on the extension rail for movement relative to the extension rail between a blocking position in which the latch blocks the roller from rolling outward off the cell pan and a non-blocking position in which the latch does not block the roller from rolling outward off the cell pan;
• wherein the latch is supported on the extension rail to be driven from the blocking position to the non-blocking position by advancing contact of the lift pan upon movement of the lift pan into the aligned position;
• and
• the latch is supported on the extension rail to return from the non-blocking position to the blocking position under the force of gravity upon removal of the lift pan from the aligned position.

An apparatus for use with a circuit breaker, a cell pan configured to support the circuit breaker in a switchgear cell, and rollers supporting the circuit breaker on the cell pan for horizontal draw-out movement from the cell pan, the apparatus comprising:

• a lift pan configured to carry the circuit breaker outside of the switchgear cell, the lift pan having a track for a roller on the circuit breaker;
• an extension rail configured to interconnect the lift pan with the cell pan in an aligned position for the track to receive the roller upon horizontal draw-out movement of the circuit breaker from the cell pan;
• and
• a latch supported on the extension rail for movement relative to the extension rail between a blocking position in which the latch blocks the roller from rolling outward off the cell pan and a non-blocking position in which the latch does not block the roller from rolling outward off the cell pan, wherein the latch is configured to move from the blocking position to the non-blocking position under the influence of the lift pan upon movement of the lift pan into the aligned position;
• wherein the latch is supported on the extension rail to move into the blocking position under the force of gravity upon removal of the lift pan from the aligned position.

An apparatus for use with a circuit breaker, a cell pan configured to support the circuit breaker in a switchgear cell, and rollers supporting the circuit breaker on the cell pan for horizontal draw-out movement from the cell pan, the apparatus comprising:

• a lift pan configured to carry the circuit breaker outside of the switchgear cell, the lift pan having a track for a roller on the circuit breaker;
• an extension rail configured to interconnect the lift pan with the cell pan in an aligned position for the track to receive the roller upon horizontal draw-out movement of the circuit breaker from the cell pan;
• and
• a latch supported on the extension rail for movement relative to the extension rail between a blocking position in which the latch blocks the roller from rolling outward off the cell pan and a non-blocking position in which the latch does not block the roller from rolling outward off the cell pan, wherein the latch is configured to move from the blocking position to the non-blocking position under the influence of the lift pan upon movement of the lift pan into the aligned position;
• wherein the latch is supported on the extension rail to normally remain in the blocking position under the force of gravity.