Forklift and inching control method of forklift

A forklift comprising:

• a variable displacement hydraulic pump which is driven by an engine;
• a hydraulic motor for forming a closed circuit between the hydraulic pump and the hydraulic motor, the hydraulic motor being driven by pressure oil discharged from the hydraulic pump;
• driving wheels which are driven by the hydraulic motor;
• a working machine which is hydraulically driven by a variable displacement working machine hydraulic pump driven by the engine;
• an accelerator operating unit for increasing or decreasing a fuel injection amount to the engine;
• an inching operating unit for operating an inching ratio as a decrease ratio of a target absorption torque of the hydraulic pump by the stepping of an inching pedal;
• an actual engine speed detecting unit for detecting an actual engine speed of the engine;
• a target engine speed calculating unit for calculating a target engine speed corresponding to the operation amount of the accelerator operating unit;
• an inching ratio calculating unit for calculating the inching ratio corresponding to the operation amount of the inching operating unit;
• a modulation control unit for setting an output time constant of the inching ratio in response to a speed difference between the target engine speed and the actual engine speed so as to perform a modulation control outputting a correction inching ratio having the output time constant set thereto;
• and
• an output control unit for outputting an instruction of an absorption torque which decrease the target absorption torque at the correction inching ratio output from the modulation control unit to the hydraulic pump.