METHOD AND APPARATUS FOR SAFE OPERATION OF SELF PROPELLED CONCRETE SAW

摘要

A concrete saw utilizing a transmission (50) having both forward and reverse, high and low speed ranges separated by a neutral state. A neutral starts switch prevents the engine from being started while the transmission (50) is in gear. An automatic parking brake assembly (80) is mounted to the frame (4) proximate the drive wheel (68), and engages the drive wheel (68) when the ignition switch (260) is off or the battery (200) is disengaged or dead. The drive wheel (68) is immobilized whenever the transmission (50) is shifted to the neutral state. An override switch (250) bypasses the automatic application of the brake assembly when the transmission (50) is placed in neutral. The brake (80) is disengaged only when the engine start switch (260) is turned on. An override switch (207) stops the engine, blade and engages the parking brake (80). A hydraulic system (18) for raising and lowering the saw blade is inactivated when the engine start switch (260) is off or when the battery (200) fails.