Abstract.A new type of engine transmission mechanism based on gears and racks is introduced,which is mainly composed of a pair of incomplete gears with overrun clutch, a composite rack and a bevel gear train.With the interval meshing of incomplete gears with composite rack, the reciprocating linear motion of piston is transmitted and eventually converted to continuous and rotational movement by the bevel gear train.Compared with traditional crank-connecting rod mechanism, the new drive mechanism performs with higher transmission efficiency, more stable power output and lower vibration noise.

In this paper, the energy consumption and its distribution of forklift in various working conditions are analyzed through experiments, and the main factors of energy consumption are found, which can find a breakthrough for system energy saving and provide theoretical basis for subsequent research. According to the measured battery output voltage and current of the electric forklift, the walking system accounts for about 42.7% of the overall energy consumption of the hydraulic system, the steering system accounts for about 13% of the overall energy consumption of the hydraulic system, the pitch system accounts for about 0.3% of the overall energy consumption of the hydraulic system, and the lifting system accounts for the largest proportion of the overall energy consumption of the hydraulic system, reaching about 44%.