The two is: first, according to the advantages and disadvantages of truck type, the self lifting mechanism of truck for link combination type lifting device.
二是：首先，根据自卸车类型的优缺点，确定了自卸车的举升机构为连杆组合式举升装置。
2
Offset driving wheel in combination with castor wheel increase stability of truck during lifting, while minimize the maintenance frequency compared to a single central wheel.