Impact Absorbing Gate

Abstract

An impact absorbing gate includes a first upright having a first proximal end attached to a surface and a first distal end, a second upright having a second proximal end attached to a surface and a second distal end, an arm having a first end and a second end, the first end being pivotably coupled to the first distal end of the first upright at a pivot point, and a bistable mechanism disposed in the first upright and configured cause the arm to rotate to a fully opened position when the arm is rotated to an angle in a first range of angles and to cause the arm to rotate to a fully closed position when the arm is rotated to an angle in a second range of angles.

What is claimed is: 
     
         1 . An impact absorbing gate comprising:
 a first upright having a first proximal end attached to a surface and a first distal end;   a second upright having a second proximal end attached to a surface and a second distal end;   an arm having a first end and a second end, the first end being pivotably coupled to the first distal end of the first upright at a pivot point; and   a bistable mechanism disposed in the first upright and configured cause the arm to rotate to a fully opened position when the arm is rotated to an angle in a first range of angles and to cause the arm to rotate to a fully closed position when the arm is rotated to an angle in a second range of angles.   
     
     
         2 . The impact absorbing gate of  claim 1  further comprising an impact absorbing pivotable coupling attaching the first end of the arm to the first distal end of the first upright, the impact absorbing pivotable coupling including:
 a hollow body extending through the first end of the arm; 
 a bearing disposed within the hollow body, the bearing being rotatable relative to the hollow body; 
 a resilient material disposed within the hollow body, and 
 a fastener extending through the hollow body, the bearing, the resilient material, the first end of the arm, and the first distal end of the first upright, 
 wherein the pivotable coupling is configured to permit movement of the arm with three degrees of freedom relative to the first upright. 
 
     
     
         3 . The impact absorbing gate of  claim 1  wherein:
 the second upright includes an opening and a catch disposed in the opening, the catch including a notch, 
 the second end of the arm is configured to be received in the opening of the second upright and includes a pin configured to be received in the notch of the catch, 
 wherein, in the absence of a predetermined amount of force being applied to the arm, the pin is not received in the notch of the catch such that the second end of the arm can freely move out of the opening of the second upright and, in the presence of the predetermined amount of force being applied to the arm, the pin is received in the notch such that the second end of the arm is prevented from moving out of the opening of the second upright. 
 
     
     
         4 . The impact absorbing gate of  claim 1  wherein one or both of the first upright and the second upright includes a rotatable bumper. 
     
     
         5 . The impact absorbing gate of  claim 4  wherein the rotatable bumper includes a cylindrical body configured to rest on and rotate about a cylindrical rail attached to the upright. 
     
     
         6 . The impact absorbing gate of  claim 1  further comprising a nylon strap extending through arm. 
     
     
         7 . The impact absorbing gate of  claim 6  further comprising pivotable coupling attaching the first end of the arm to the first distal end of the first upright, wherein the nylon strap has a loop disposed at its first end and a part of the pivotable coupling extends through the loop. 
     
     
         8 . The impact absorbing gate of  claim 7  wherein a second end of the nylon strap includes a second loop and the second end of the arm includes a pin, wherein the pin extends through the loop. 
     
     
         9 . The impact absorbing gate of  claim 1  wherein the bistable mechanism includes a spring, a strut, and a linkage. 
     
     
         10 . The impact absorbing gate of  claim 9  wherein the spring and the strut are arranged coaxially, with the strut inside the spring. 
     
     
         11 . The impact absorbing gate of  claim 10  wherein the first range of angles and the second range of angles are separated by a threshold angle. 
     
     
         12 . The impact absorbing gate of  claim 11  wherein the threshold angle is adjustable. 
     
     
         13 . The impact absorbing gate of  claim 12  wherein the threshold angle is adjustable by adjusting a tension in the spring. 
     
     
         14 . The impact absorbing gate of  claim 12  wherein the threshold angle is adjustable by adjusting a configuration of elements of the linkage. 
     
     
         15 . The impact absorbing gate of  claim 12  wherein the threshold angle is adjustable by adjusting the strut. 
     
     
         16 . The impact absorbing gate of  claim 12  wherein the first proximal end of the first upright is attached to the surface using a first impact absorbing anchoring assembly and the second proximal end of the second upright is attached to the surface using a second impact absorbing anchoring assembly. 
     
     
         17 . The impact absorbing gate of  claim 1  wherein the arm is coupled to the surface through the bistable mechanism. 
     
     
         18 . The impact absorbing gate of  claim 1  further comprising a second arm extending between the first and second uprights and rotatably coupled to the arm. 
     
     
         19 . The impact absorbing gate of  claim 1  wherein the opening in the second upright is tapered. 
     
     
         20 . A gate comprising:
 a first post assembly;   a second post assembly having an opening and a catch disposed in the opening, the catch including a notch;   a rail assembly with a first end rotatably coupled to the first post assembly and a second end configured to be received in the opening of the second post assembly, the second end including a pin configured to be received in the notch of the catch;   wherein, in the absence of a predetermined amount of force being applied to the rail assembly, the pin is not received in the notch of the catch such that the second end of the rail assembly can freely move out of the opening of the second post and, in the presence of the predetermined amount of force being applied to the rail assembly, the pin is received in the notch such that the second end of the rail assembly is prevented from moving out of the opening of the second post.