START SAFETY CIRCUIT ARRANGEMENT IN A WORK APPARATUS HAVING AN INTERNAL COMBUSTION ENGINE

摘要

A start safety circuit arrangement is incorporated into a work apparatus having an internal combustion engine. Combustion air and fuel are supplied to the combustion chamber by a control unit for the engine operation. The fuel/air mixture in the combustion chamber is ignited by an ignition plug. An operating mode selector has a start position for enriching the fuel/air mixture. A safety brake device in an operating mode brakes the work tool. A start position sensor is arranged on the operating mode selector and a brake position sensor is associated with the safety brake device. The status signal of the brake position sensor and the status signal of the start position sensor are combined to cause the control unit to disable the engine operation if the operating mode selector is in start position (III) and the safety brake device is in its standby mode (B).