Abstract: A chain saw including an improved suspension system characterized by a U-shaped hand grip means extending transversely across a longitudinal median plane of a guide bar means, with the U-shaped hand grip means being contiguous with a longitudinally extending rear handle and serving to house, at least in part, a portion of the chain saw vibration isolation system.Generally longitudinally aligned vibration isolation units are constrained by abutment means and axially oppositely directed mounted shaft means to impede axially oppositely directed movements of a vibration generating assembly relative to the chain saw suspension system.

Abstract: A hand portable chain saw with a movable safety bar for actuating a chain brake has a bracket and a lineally-acting spring which together provide a detent for holding the safety bar in the nonbraking operating position, but yet accelerate the braking movement of the safety bar upon disengagement from the detent.The carrying handle for a portable chain saw encircles the top and both sides of the saw housing to enhance both operator safety and convenience. The brake-actuating safety bar on the saw has a similar wrap-around contour to ensure engagement by the operator in the event of untoward movement of the saw for essentially any sawing position.

Abstract: A chain saw safety brake including a snap-acting, over-center actuating mechanism.A chain saw safety brake and method of operation characterized by an actuation accelerator interposed between a brake mechanism and a brake actuating mechanism. A biasing means is operable to bias the brake actuating means toward a nonactuating position with a relatively lower biasing force. The biasing means is operable to bias the brake actuating means toward an actuating position with a relatively higher biasing force.

Abstract: A portable chain saw includes a flexible brake band for stopping the cutter chain. A sensing arm is engageable by an arm or hand of an operator to be swung forwardly to tighten the brake band. The sensing arm is continuously biased forwardly to a braking position by a power torsion spring. The same torsion spring also serves to normally hold the sensing arm in a rest position. A latch can be utilized to transmit latching forces from the torsion spring to the sensing arm. Alternatively, the torsion spring itself can serve as a latch to resist forward movement of the sensing arm. The torsion spring is yieldable to enable the sensing arm to be unlatched in response to being struck by the arm or hand of an operator and then swung forwardly by the torsion spring.

Abstract: A chain saw safety brake including a snap-acting, over-center actuating mechanism.A chain saw safety brake and method of operation characterized by an actuation accelerator interposed between a brake mechanism and a brake actuating mechanism. A biasing means is operable to bias the brake actuating means toward a nonactuating position with a relatively lower biasing force. The biasing means is operable to bias the brake actuating means toward an actuating position with a relatively higher biasing force.