An electronic security system for a parking meter includes a vault door having a spring-biased contact terminal for making breakable electrical contact with a housing hinge bracket contact terminal mounted in a vault opening. An electronic lock control circuit is able to communicate with a meter control...http://www.google.de/patents/US6467602?utm_source=gb-gplus-sharePatent US6467602 - Electromechanical parking meter door communications interface
Electromechanical parking meter door communications interface
