| 摘要 |
<p>An impact detection system for an industrial door, the system including two members that are releasably coupled to each other to move together with the door as it travels; disposed beyond the doorway openi ng is a radiation emitter and a radiation detector, preferably packaged together in a photoeye device, and emitting a beam of radiation; th e first member carries a reflector that, when the two members are coupled, reflects the radiation back to the photoeye, and that is movabl e to a position wherein it does not reflect the radiation back to the photoeye in response to separation of the two members caused by the door being impacted, the change in state from 1) the radiation being reflected to the photoeye to 2) the radiation not being reflected to t he photoeye thus serves as an indication that an impact on the door has occurred.</p> |
