1. Both bridge girders approach the crossover track. The operator pushes a button powering a gear motor that activates a pair of rollers.

2. The bridges line up with the crossover track. The rollers move from the interlocking beam toward a wedge type engaging mechanism on the crossover track.

3. The rollers make contact with the wedge and self-align within 1-1/4" horizontal range. As both beams are interlocked, forks on powered and non-powered beams are raised for free passage of carrier.

4. To disengage the interlock, the operator pushes a second button. Motor driven rollers move back and away from wedge, allowing forks to drop and make contact with rail tread. This prevents the carrier from traveling off the open end of the beam.