The function of a manual hydraulic pump is to convert the mechanical energy of a power source (such as electric motors and internal combustion engines) into the pressure energy of a liquid.

Operation Principle: The cam is rotated by an electric motor. As the cam pushes the plunger upward, the sealed volume between the plunger and cylinder decreases, causing the oil to be extruded out through a one-way valve to the required location. When the cam rotates to the descending part of the curve, the spring forces the plunger downward, creating a certain vacuum, and the oil in the reservoir is drawn into the sealed volume due to atmospheric pressure. The cam causes the plunger to continuously rise and fall, resulting in the cyclic reduction and expansion of the sealed volume, thereby continuously suctioning and discharging oil.