Working principle of gear pump drive device

The gear pump is driven by an independent motor, which can effectively block upstream pressure pulsation and flow fluctuations. The pressure pulsation at the outlet of the gear pump can be controlled within 1%. Using a gear pump on the extrusion production line can increase the flow output speed and reduce the shearing and residence time of materials in the extruder

External meshing gear pump is a widely used gear pump, and generally refers to external meshing gear pump. Its structure is shown in Figure 5-14, mainly composed of driving gear, driven gear, pump body, pump cover, and safety valve. The sealing space composed of the pump body, pump cover, and gears is the working chamber of the gear pump. The two gear shafts are installed in the bearing holes on the two pump covers, and the driving gear shaft extends out of the pump body, which is driven by an electric motor to rotate. The external meshing gear pump has a simple structure, light weight, low cost, excellent performance, and a wide range of applications. When the gear pump is working, the driving wheel rotates together with the electric motor and drives the driven wheel to rotate accordingly. When the meshing teeth on one side of the suction chamber gradually separate, the volume of the suction chamber increases, the pressure decreases, and the liquid in the suction pipe is sucked into the pump; The inhaled liquid is divided into two paths and pushed into the discharge chamber by the gear in the tooth groove. After the liquid enters the discharge chamber, due to the continuous meshing of the teeth of the two gears, the liquid is compressed and enters the discharge pipe from the discharge chamber. The driving gear and driven gear rotate continuously, allowing the pump to continuously suck in and discharge liquid. The pump body is equipped with a safety valve. When the discharge pressure exceeds the specified pressure, the conveyed liquid can automatically open the safety valve, allowing the high-pressure liquid to return to the suction pipe

The internal meshing gear pump consists of a pair of internal gears that mesh with each other, as well as a crescent shaped component and pump casing in between. The function of crescent shaped components is to separate the suction chamber from the discharge chamber. When the driving gear rotates, a local vacuum is formed at the point where the gear disengages, and the liquid is sucked into the pump and filled between the teeth of the suction chamber. Then, it enters the discharge chamber in two paths along the inner and outer sides of the crescent shaped part. At the point where the teeth engage, the liquid present between the teeth is squeezed and sent into the discharge pipe. Gear pumps have the characteristics of self suction capacity, flow rate independent of discharge pressure, and no suction or discharge valves on the pump casing. They have simple structure, uniform flow rate, and excellent operation, but low efficiency, high noise and vibration, and are prone to wear and tear. They are used to transport various types of oils that are non corrosive, non solid particles, and have lubrication ability. The temperature generally does not exceed 70 ℃, such as lubricating oil, edible vegetable oil, etc