Safety lever system in cab of excavator

A safety lever system in a cab of an excavator, the system comprising:

• a fixed plate fixed in the cab, having a rotation axis;
• operator's seat fixed on the fixed plate;
• a control box movably installed on the rotation axis of the fixed plate as one body to descend or ascend around the rotation axis, and having a control lever;
• a safety lever protruded to the front side of the control box, and if pulled upward by an operator, tilting the control box upward by interlocking;
• a tilting device, which is connected to one end of the safety lever, operates with the control box as one body, is hinged at a hinge axis and interlocks in an operational direction of the safety lever around the axis for rotating the control box and then immobilizing or fixing the control box when stopped;
• and
• a limit means installed on one side of the control box for applying/short-circuiting power to/from the control box by rotating at the same angle as the tilted control box,
• wherein the tilting device is comprised of:
• a rotating bracket connected to one end of the safety lever, and is hinged at a hinge axis, being extended;
• a spring bracket hinged equally at the hinge axis below the rotating bracket;
• and
• a first cylinder rotatably installed on the end of the rotating bracket.