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Manually depressible automatically deployable spring balanced bollard

  • US 4,715,742 A
  • Filed: 03/17/1986
  • Issued: 12/29/1987
  • Est. Priority Date: 03/17/1986
  • Status: Expired due to Fees
First Claim
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1. A manually depressible spring balanced bollard type trafficway barrier for arresting vehicles, and including;

  • a below grade level foundation of substantial depth, having a grade level opening at its upper end and having a bottom support,a spring lift means centered upon the bottom support and supporting a bollard in a position of balanced equilibrium between a depressed position and an extended position,the bollard being of tube form entered through the foundation grade level opening and centered over and carried by the spring lift means in said balanced condition extending upward from the grade level,and releasable lock means carried by the foundation and engaged with spaced stops on the bollard, one stop engageable to hold when the bollard is depressed to grade level and the other stop engageable to hold the bollard when extended by the lift means, whereby the spring lift means stores potential energy by depression of the bollard to grade level and subsequently released for transfer into kinetic energy and assisted by inertia to lift the bollard above the position of balanced equilibrium and to the other stop.

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