Portable circular power saw with optical alignment

Abstract

A laser emitter projects a planer light beam to form an optical guideline on a work piece extending in a cutting direction of saw blade. The laser emitter is arranged behind, in the cutting direction, a tangential line of the circumference of the saw blade at an intersection of a bottom surface of the base and the circumference at a front side of the base in the cutting direction. The laser emitter forms the optical guideline behind the intersection in the cutting direction. The laser emitter is supported in respect of the saw blade slidingly in a direction defined by a rotation axis of the saw blade. The saw cover may have a window to transmit the laser beam toward the cutting point. A shutter selectively shutting the window may be provided.

1 . A cutting tool, comprising: 
 a housing;    a motor which is supported by the housing and rotates a detachable saw blade to cut a work piece;    a saw cover which is supported by the housing and has a shape so as to cover a portion of the saw blade;    a fixing member which is fixed to the saw cover;    a laser emitter which emits a planer light beam to form an optical guide line on an upper surface of the work piece; and    an adjustment mechanism which is disposed between the fixing member and the laser emitter and causes the laser emitter to be movable in parallel to a rotation axis of the saw blade,    wherein the adjustment mechanism comprises:    a sliding member which supports the laser emitter;    a pin which guides the sliding member to be moved;    a bolt which penetrates through a through hole of the fixing member and is engaged with a screw hole of the sliding member; and    a spring which is placed between the fixing member and the sliding member and biases the sliding member,    and wherein the laser emitter is moved in parallel to the rotation axis of the saw blade when the bolt is rotated.    
   
   
       2 . The tool according to  claim 1 , wherein the spring is formed of a coil spring, and the bolt is covered with the spring.  
   
   
       3 . A laser assembly for a cutting tool, comprising: 
 A fixing member which is fixed to a cutting tool having a rotatable saw blade;    A laser emitter which emits a planer light beam to form an optical guide line on an upper surface of a work piece; and    an adjustment mechanism which is disposed between the fixing member and the laser emitter and causes the laser emitter to be movable in parallel to a rotation axis of the saw blade,    wherein the adjustment mechanism comprises:    a sliding member which supports the laser emitter;    a pin which guides the sliding member to be moved;    a bolt which penetrates through a through hole of the fixing member and is engaged with a screw hole of the sliding member; and    a spring which is placed between the fixing member and the sliding member and biases the sliding member,    and wherein the laser emitter is moved in parallel to the rotation axis of the saw blade when the bolt is rotated.    
   
   
       4 . The assembly according to  claim 3 , wherein the spring is formed of a coil spring, and the bolt is covered with the spring.  
   
   
       5 - 17 . (canceled)