Parking stall monitor

A parking stall monitor for indicating unauthorized use of a parking stall comprising:

• a clock;
• a vehicle presence sensing means operatively associated with said clock to detect the presence of a vehicle in said parking stall during a time window of predetermined duration, said presence sensing means being periodically enabled for successive said time windows by said clock;
• an alarm means operatively associated with said vehicle sensing means to provide an audible warning upon the detection of a vehicle in said parking stall during said time window;
• means for selective disarming and arming of at least one of said clock, said vehicle presence sensing means and said alarm means to enable an authorized vehicle to occupy said parking stall without generating said audible warning, said selective arming and disarming means including a transmitter adapted to transmit an encoded signal and a receiver adapted to receive said encoded signal from said transmitter and in response thereto, to provide an arm/disarm signal to said presence detecting means.

A parking stall monitor for indicating unauthorized use of a parking stall comprising:

• a clock;
• transmitting means operatively associated with said clock to periodically transmit a first burst of pulses in the direction of said stall during a first time interval;
• receiving means operatively associated with said clock to periodically detect during a second time interval said burst of pulses after being reflected off of a vehicle in said stall, said first and second time intervals being staggered in time by a delay, said delay and said second time interval being of a duration so that said receiving means does not detect signals reflected off of a vehicle located in an area outlying said stall;
• an alarm means operatively associated with said clock and said receiving means to provide an audible warning upon the detection of a vehicle in said parking stall during said second time interval;
• means for selective disarming and arming of at least one of said clock, said receiver and said alarm means to enable an authorized vehicle to occupy said parking stall without generating said audible warning, said selective means being located within said authorized vehicle.

A monitor for a parking stall, the stall having a first end and a second end for vehicle entry and exit, said second end being opposite said first end and spaced therefrom at least a distance equal to the length of a vehicle, comprising:

• a monitor located outside said stall adjacent said first end;
• means in said monitor to sense the presence of a vehicle in said stall but not in an area outlying said stall;
• energy transmitting means located at said monitor for directing energy into said parking stall from said first end toward said second end;
• means for receiving reflected energy from a vehicle in said parking stall, said reflected energy directed from said vehicle toward said first end;
• means for providing a warning signal upon reception of said reflected energy;
• and
• means for selective disarming and arming of at least one of said energy transmission means, said means for receiving and said means for providing a warning signal, thereby to enable an authorized vehicle to occupy said parking stall without generation of said warning signal.