Digital lap speed display for model race track - is actuated by car striking switch at start and end of lap

摘要

A digital display unit (4) using light emitting diodes is used to display the time required for the model car (5) to cover one lap of the course. A chronometer (1) is connected to two switches (2) and (3) and to the digital display unit. Whilst the unit is operating, switch (3) is closed and switch (2) is open. As the toy car passes switch (2) it closes and starts the chronometer (1) with the time displayed on the digital display unit (4). At the end of a lap the car strikes the switch a second time but in this case opens the switch which stops the chronometer and displays the lap time.