Patent ID: 8109474

Claim:
A portable train detector for installing adjacent to a selected rail of a train track, a train being on said track, said rail having a length, a top, a base and a bottom, said train having wheels, comprising: a housing; at least one ultrasonic transducer positioned within said housing, said transducer(s) producing and detecting ultrasonic pulses aimed upwards above the top of said selected rail, such ultrasonic pulses striking and reflecting off a wheel of said train for detection of said train; wherein said housing is laterally positionable perpendicular to said length of said selected rail for placing said transducer(s) in a plane a distance from said rail; transmitting means disposed within said housing for broadcasting the detection of said train on said track; mounting means for positioning and mounting said housing in alignment with and adjacent to said selected rail; first and second ultrasonic transducers positioned within said housing a distance apart from one another, said first and second transducers producing and detecting said ultrasonic pulses aimed upwards from said plane at approximately a 45 degree angle to a point above said top of said selected rail; said first and second ultrasonic transducers positioned approximately 10 inches apart from one another; said mounting means have a length and an axis, said mounting means positioned under said selected rail of said track; said housing mounted on said mounting means; and clamping means for engaging said mounting means to said base of said selected rail, said mounting means being laterally positionable perpendicular to said length of said selected rail so as to place said first and second transducers a distance of between 0.25 inch-20 inches from said selected rail, said clamping means being tightenable to said selected rail when said housing is at a selected distance from said selected rail.