Blocking arrangement for parking places and thoroughfares - has ultrasonic or IR transmitter-receiver pair to detect presence or absence of vehicle

摘要

A blocking arrangement for parking places and throughfares contains an ultrasonic transmitter and receiver or an infrared transmitter and receiver. Alternatively, it can contain an interrupted magnetic field. The transmitter/receiver or magnetic field arrangement detects the presence or absence of a vehicle above blocking post when the post is lowered and the system prevents the post from being raised if a vehicle is detected. USE/ADVANTAGE - Prevents vehicles from being damaged by blocking raised by mistake.