| 主权项 |
1. A chain containment device for use in a chain saw, said chain saw including
a chain bar mount, said chain bar mount comprising a proximal ring and a distal base, said chain bar mount having an interior surface and an opposite, exterior surface; a motor assembly attached to the interior surface of the ring portion, said motor assembly including a motor drive shaft that extends exteriorly through the ring portion; a drive sprocket in driven engagement with the motor drive shaft for rotation therewith about the drive shaft axis whenever the motor is energized, said drive sprocket protruding exteriorly from the ring; a chain guide bar that extends from a proximal end portion to an opposite, distal end portion in a direction normal to the motor drive shaft axis, the proximal end portion being attached to the exterior surface of the base of the chain bar mount, said chain guide bar having a straight, upper edge and an opposite, straight, lower edge joined by a curved, distal edge and having a peripheral groove that extends continuously along said edges; a saw chain tensioner attached to an exterior surface of the proximal end portion of the chain guide bar and to the base of the chain bar mount by fasteners, said tensioner including means for moving the chain guide bar proximally and distally with respect to the chain bar mount; and a closed-loop, cutting chain looped around the drive sprocket and the peripheral groove of the chain guide bar;said device comprising:
deflector means for deflecting, during operation of the chain saw, a detached or broken cutting chain exteriorly away from the drive sprocket to thereby deneergize the cutting chain;
wherein said deflector means is disposed below the chain guide bar and distal to the drive sprocket, and obliquely crosses a plane that contains the chain guide bar from a distance slightly interior to a plane that contains the interior surface of the chain guide bar to a distance exterior to a plane that contains the exterior surface of the chain guide bar; andsaid deflector means includes
ramp means having an exterior surface that extends proximally and exteriorly at an oblique angle with respect to a plane that contains the exterior surface of the chain guide bar; andmeans for attaching the ramp means to the chain saw; and chain catcher means for catching and arresting a detached cutting chain after it has been deflected exteriorly away from the drive sprocket, said means being attached to the chain saw and spaced apart exteriorly from the proximal ring of the chain bar mount. |
