发明名称 Security door with improved sensor for detecting unauthorized passage
摘要 A control system for a revolving door includes an ultrasonic sensor having multiple sensor heads. The door has a housing, and multiple moveable compartments formed by door wings attached to and radially extending from a rotatable axis. The sensors emit energy waves into the housing in bursts, then receive echoes from any objects, including people, in the chambers. The sensors are activated when the door is activated by an authorized user. A controller stores a binary "echo" or "no echo" signal in memory in response to an emitted energy wave. The memory is formed by multiple arrays, each array having a column associated with a particular sensor and used for storing echo signals from a particular ultrasonic burst. Each bit in a column represents incremental ranges of objects from the sensor head, and the controller stores the "echo" or "no echo" signal in an appropriate bit based on the elapsed time from the preceding burst. To avoid interference from reverberations, the burst cycle time is varied, the amount of time following each burst is sufficiently greater than the time for receiving an echo from the floor of the housing so that reverberations will die down, and multiple arrays of echo data are filled with corresponding results and ANDed together to form a results array. The controller uses the results array to determine whether there is an object in an unauthorized chamber. The system also ignores signals which are given from the top of a door wing passing by a sensor head.
申请公布号 US5097454(A) 申请公布日期 1992.03.17
申请号 US19900607236 申请日期 1990.10.31
申请人 SCHWARZ, MILAN 发明人 SCHWARZ, MILAN;MAYER, ROBERT
分类号 E05G5/00;G01S15/04;G01S15/87;G07C9/00;G08B13/16 主分类号 E05G5/00
代理机构 代理人
主权项
地址