Table saw having a measurement and display system

Abstract

A table saw having various embodiments of a measurement and display system. Several embodiments have at least one fence rail on which a removable fence is movably supported and comprise an elongated sensor strip that is located adjacent the fence rail and a sensing unit that is supported and positioned adjacent to the sensor strip and is capable of providing an electrical signal to a display unit that is indicative of the position of the sensor unit relative to the elongated sensor strip. A processing unit is operatively connected to the sensing unit and display unit to provide a digital readout of the position of the sensing unit. A switch is connected to the processing unit and is adapted to provide a zero or reference setting position.

1 . A linear measurement and display system for a table saw of the type which has a removable fence that is laterally adjustable relative to the blade of the saw along a fence rail located on the front of the table saw, said system comprising: 
 a sensor strip positioned generally parallel to the fence rail, said sensor strip configured to provide digital signals that are indicative of specific positions along the length thereof;    a sensing unit movable along said sensor strip and operatively connected to the fence, said sensing unit generating signals indicative of the specific lateral position of the fence;    a switch operatively connected to a processing unit for establishing a reference position when activated;    a processing unit connected to said sensing unit for receiving said position indicating signals and for calculating the distance between said fence and said reference position and for generating display signals indicative of said calculated distance; and    a display unit electrically connected to said processing unit configured to receive said display signals and provide a digital display of said calculated distance.    
   
   
       2 . A system as defined in  claim 1  wherein said sensor strip is connected to the fence rail.  
   
   
       3 . system as defined in  claim 1  further comprising a member physically connecting said sensing unit, said display unit and said processing unit together, the fence having a pin for engaging a slot in said member, whereby the fence is physically coupled to said sensing unit when the fence is attached to the fence rail.  
   
   
       4 . A system as defined in  claim 1  wherein said processing unit is capable of generating display signals that cause said display unit to display said calculated distance in one of English or metric units.  
   
   
       5 . A system as defined in  claim 1  wherein said processing unit is housed with said sensing unit, said table saw further comprising a battery for powering said processing unit and said sensing unit.  
   
   
       6 . A system as defined in  claim 1  further comprising a display rail extending parallel to said sensor strip, said display unit being slidable along said display rail and being mechanically and electrically connected to said sensing unit and said processing unit.  
   
   
       7 . A system as defined in  claim 1  further comprising a table top extension that abuts said main table top and at least one table extension rail, said table top extension being connected to the fence rail, the fence rail being slidably attached to said table extension rail so that said table top extension can be separated from said main table top to increase the effective area of the top of said table saw.  
   
   
       8 . A system as defined in  claim 6  wherein at least one ribbon connector electrically connects said sensing unit with said display unit and said processing unit.  
   
   
       9 . A system as defined in  claim 3  wherein said switch is mounted adjacent said display unit.  
   
   
       10 . A system as defined in  claim 3  further comprising an on/off switch for controlling power to said processing unit.  
   
   
       11 . A system as defined in  claim 3  further comprising a switch for selectively alternating between English and metric units of length.