Start safety circuit arrangement in a work apparatus having an internal combustion engine

A start safety circuit arrangement in a work apparatus, the work apparatus including an internal combustion engine having a cylinder defining a combustion chamber and having a spark plug in said combustion chamber;

• a control unit configured for the operation of said engine by controlling a supply of combustion air and fuel to said combustion chamber to form an air/fuel mixture and igniting said air/fuel mixture via said spark plug;
• an operating mode selector for bringing said engine into operation;
• said operating mode selector including an operating position and start position (III) for enriching said air/fuel mixture;
• a work tool operatively connected to said engine;
• a brake unit operatively connected to said work tool;
• and, a safety brake device configured to brake said work tool via said brake unit in an operating state of said work tool and configured to enable said work tool in an operationally-ready state (B) when said brake unit is released;
• and, said start safety circuit arrangement comprising:
• an operation sensor assigned to said safety brake device and configured for emitting a first status signal as to the operating state of said safety brake device;
• a position sensor arranged on said operating mode selector and configured for emitting a second status signal;
• and,
• a circuit for combining said first and second status signals so as to cause said control unit to disable said operation of said engine when said operating mode selector is in said start position (III) and said safety braking device is in said operationally ready state (B) with said brake unit released.