Patent ID: 7814706

Claim:
A safety system for use with a boom gate, said boom gate having a boom and a boom moving means for moving said boom between a down position and an up position, said safety system comprising: a. a spring housing affixed to said boom moving means, wherein said spring housing has an end plate with a first opening passing therethrough; b. a combination hinge, including i. a vertical pivot joint attached to said end plate of said spring housing and configured to allow said boom to deflect in a horizontal direction; ii. an inside pivot plate pivotally attached to said end plate by said vertical pivot joint and said inside pivot plate having a second opening passing therethrough; iii. a horizontal pivot joint attached to said inside pivot plate and configured to allow said boom to deflect in a vertical direction; iv. an outside pivot plate pivotally attached to said inside pivot plate by said horizontal pivot joint; v. said boom being attached to said outside pivot plate; vi. a cable having a first end and a second end, wherein said cable passes through said first and second opening with said first end of said cable being attached to said outside pivot plate and said second end of said cable lying within said spring housing; vii. a compression spring connecting said second end of said cable to said spring housing with said compression spring being positioned to place tension on said cable so that said cable biases said outside pivot plate toward said inside pivot plate and said inside pivot plate toward said end plate; and c. a boom deflection detector for detecting movement of one of said pivot plates relative to said spring housing.