Patent ID: 7743513
Filing Date: 2010-06-29
Classification: B27B,Y10T

Abstract:
1. A chainsaw comprising: a housing; a power source positioned within said housing; a guide bar partially enclosed within the housing and extending from said housing; an endless chain wrapped around said guide bar and rotated by said power source; a cam lever positioned outside said housing and movable between a first position and a second position; a cam attached to said cam lever, wherein said cam rotates when said cam lever moves between said first position and said second position; a spring positioned between said cam and said guide bar such that when said cam rotates, said spring moves closer or farther away from said guide bar, thereby adjusting the tension of the guide bar; a rotatable chain-tightening knob on said housing and underneath said cam lever such that said chain-tightening knob is accessible when said cam lever is moved from said first position to said second position; a gear within said housing that meshes with said chain-tightening knob; and a tensioning screw interacting with said gear and said guide bar, wherein rotation of said chain-tightening knob causes said guide bar to move.