Patent ID: 6229455
Filing Date: 2001-05-08
Classification: G07F

Abstract:
A vehicle detector unit for use with an electronic parking meter for detecting the presence or absence of a vehicle in a corresponding parking space, said unit comprising:a first signal emitting sensor positioned adjacent the corresponding parking space for transmitting a first signal towards the parking space in a first direction and for receiving a reflection of said first signal;a second signal emitting sensor positioned adjacent the corresponding parking space for transmitting a second signal towards the parking space in a second direction different from said first direction and for receiving a reflection of said second signal;processing means coupled to said first and second signal-emitting sensors for processing said reflections of said first and second signals to determine if a vehicle is positioned in the corresponding parking space, said processor means coupled to the electronic parking meter for communicating the presence or absence of a vehicle in the corresponding parking space to the electronic parking meter;means for storing a first reflected signal corresponding to an empty parking space for said first signal-emitting sensor and a second reflected signal corresponding to the empty parking space for said second signal-emitting sensor, said storing means being coupled to said processing means; anda tamper detection system, said tamper detection system being coupled to said processing means for detecting inadvertent or intentional tampering of said first or second signal-emitting sensors.