Brake mechanism for power equipment

Abstract

Brake pawls for use in safety systems for power equipment are disclosed. The brake pawls include an energy-absorbing region. The energy absorbing regions may include a deformable or collapsible region made from apertures in the brake pawl or from collapsible members or from materials of differing hardnesses, strengths, or structures.

1 . A brake pawl adapted for use with a moving cutting tool, the brake pawl comprising:
 a contact region adapted to engage the moving cutting tool; and   an energy-absorbing region adapted to absorb at least some of the energy of the moving cutting tool by permanently deforming or collapsing when the contact region engages the moving cutting tool;   where the energy-absorbing region is positioned not to make contact with the moving cutting tool when the contact region engages the moving cutting tool.   
   
   
       2 . The brake pawl of  claim 1  where the energy-absorbing region comprises at least one hole. 
   
   
       3 . The brake pawl of  claim 1  where the energy-absorbing region comprises holes. 
   
   
       4 . The brake pawl of  claim 1  further comprising a mounting region distinct from the contact region and where the energy-absorbing region is nearer the mounting region than the contact region. 
   
   
       5 . The brake pawl of  claim 1  further comprising a mounting region adapted to mount the brake pawl on a pin. 
   
   
       6 . The brake pawl of  claim 1  where the energy-absorbing region comprises an elongate aperture. 
   
   
       7 . The brake pawl of  claim 1  further comprising a mounting region adapted to mount the brake pawl on a pin and where the energy-absorbing region comprises an aperture adjacent the mounting region. 
   
   
       8 . The brake pawl of  claim 1  further comprising a mounting region and where the energy-absorbing region is between the contact region and the mounting region. 
   
   
       9 . The brake pawl of  claim 1  where the energy-absorbing region is shaped to deform or collapse. 
   
   
       10 . The brake pawl of  claim 1  where the energy absorbing region is shaped like a “T” with two ends, and where the where the two ends are adapted to mount in brackets. 
   
   
       11 . The brake pawl of  claim 1  where the energy-absorbing region is annealed aluminum. 
   
   
       12 . The brake pawl of  claim 1  where the contact region is annealed aluminum. 
   
   
       13 . The brake pawl of  claim 1  where the energy-absorbing region comprises at least one depression. 
   
   
       14 . The brake pawl of  claim 1  where the energy-absorbing region is structurally weaker than another region of the brake pawl. 
   
   
       15 . The brake pawl of  claim 1  where the contact region includes at least one hole and the energy-absorbing region comprises at least one hole. 
   
   
       16 . The brake pawl of  claim 1  where the contact region includes holes and the energy-absorbing region comprises at least one hole. 
   
   
       17 . The brake pawl of  claim 1  further comprising a mounting region distinct from the contact region, where the contact region includes at least one hole, and the energy-absorbing region is between the contact region and the mounting region. 
   
   
       18 . A brake pawl adapted for use with a moving cutting tool, the brake pawl comprising:
 a contact region adapted to engage the moving cutting tool; and   means for permanently deforming or collapsing to absorb at least some of the energy of the moving cutting tool when the contact region engages the moving cutting tool, where the means for permanently deforming or collapsing does not make contact with the moving cutting tool when the contact region engages the moving cutting tool.