Four-car lift is a large tonnage car or truck repair and maintenance units commonly used special machinery lifting equipment, four-post car lift is also very suitable for wheel alignment, because generally have four-post car lift There is a gear wheel alignment can be adjusted to ensure that level. Four-post lift its structure is divided into the fuel tank of the fuel tank and two under. Four-Post Lift the cylinder placed in the column at the top of their tanks (with beams), under the fuel tank of the cylinder is placed flat below. Four-Post Lift the cylinder rely mainly on the four corners of the chain pull, pull tanks placed at the top, this structure is simple, but the weight increases. Four-Post Lift on most secondary lift cylinder for manual or pneumatic, mechanic need to go under the operation, which is often used for secondary lifting the user inconvenient and unsafe. Safety device for pneumatic devices, if there is no gas supply is too much trouble. Under the lift cylinder rely mainly on four-poster Sola crude from the four corners of the cylinder is placed flat under tension, the force conveyed by six disc four. This structure is more compact, lower weight. Electro-hydraulic lifting usually secondary, and primary pump connected together, simply by turning the switching valve can, lifting speed, safety device for the wedge, wedge use four rod linkage, flip the lever safety device can be opened , convenient and durable.