Power saws

Abstract

Power saws and features for power saws are disclosed. Various features are particularly relevant to jobsite or benchtop table saws, such as a trunnion formed from a shaped tube, an elevation carriage, and an arbor block retention mechanism. Other features are particularly relevant to table saws, hand-held circular saws, track saws, miter saws, and band saws with active injury mitigation technology, such as an electrically isolating gear and an overmolded arbor/gear element.

1 . A power tool comprising:
 a rotatable arbor;   a blade mounted on the arbor;   a motor to spin the arbor and blade;   a detection system to detect when a person contacts the spinning blade;   a reaction system triggerable to perform an action to mitigate injury upon detection of the contact; and   an electrically isolating gear through which the motor spins the arbor.   
     
     
         2 . The power tool of  claim 1 , where the electrically isolating gear is on the arbor. 
     
     
         3 . The power tool of  claim 1 , where the electrically isolating gear includes an outer ring of conductive material and an inner ring of non-conductive material. 
     
     
         4 . The power tool of  claim 3 , where the inner ring contacts the outer ring, and further comprising splines at the contact between the inner and outer rings. 
     
     
         5 . The power tool of  claim 1 , where the electrically isolating gear is on the arbor, where the gear includes an outer ring of conductive material and an inner ring of non-conductive material, where the inner ring contacts the arbor, and where the inner ring is formed by molding over the arbor. 
     
     
         6 . The power tool of  claim 1 , where the electrically isolating gear is on the arbor, where the gear includes an outer ring of conductive material and an inner ring of non-conductive material, where the inner ring includes at least one bearing seat.