Patent ID: 7350754

Claim:
A system for automatically controlling movement of a model train within a model train track assembly, the system comprising: a length of model railway track comprising plural mechanically connected blocks of track, the model track comprising a first rail divided into electrically isolated first rail segments, a second rail configured to be electrically conductive along the entire length of the model railway track, and a third rail divided into electrically isolated third rail segments, corresponding ones of the first and third rail segments comprising part of a respective one of the connected blocks, the second rail being electrically grounded and the third rail segments being connected to respective power sources; a model train car having an electrically conductive axle configured to provide a presence detection signal caused by an electrical connection between one of the first rail segments and the second rail of the model track when the train car is on a corresponding one of the blocks of the model track; and a controller connected to the blocks of track, the controller configured to detect the presence detection signal in the corresponding one of the blocks, and to provide a control output in response to the presence detection signal reflecting presence of the model train car on the corresponding one of the blocks; wherein, the presence detection signal is electrically isolated from the power sources.