Working principle of vibrating screen

When the vibrating screen is working, the synchronous reverse rotation of the two motors causes the vibrator to generate a reverse excitation force, forcing the screen body to drive the screen mesh to make a longitudinal movement, so that the materials on the screen are periodically thrown forward a range by the excitation force, thus completing the material screening operation. It is suitable for screening sand and stone materials in quarries, and can also be used for product classification in coal preparation, mineral processing, building materials, power and chemical industries. The working part is fixed, and the material is screened by sliding along the working face. Fixed grid screen is widely used in concentrators, generally used for pre screening before coarse crushing or intermediate crushing. The utility model has the advantages of simple structure and convenient manufacture. It does not consume power and can directly unload the ore onto the screen surface. The main disadvantages are low productivity and screening efficiency, generally only 50-60%. The working face is composed of horizontally arranged rolling shafts, on which there are plates, and fine materials pass through the gap between the rollers or plates. Large materials move towards one end of the roller belt and are discharged from the end. Such sieves are rarely used in concentrators. The working part is cylindrical, the whole screen rotates around the axis of the cylinder, and the axis is generally installed with a small inclination. The material is fed from one end of the cylinder, the fine material passes through the screen hole of the cylinder shaped working surface, and the coarse material is discharged from the other end of the cylinder. The rotary speed of the cylinder screen is very low, the work is stable, and the power balance is good. However, the screen hole is easy to block, the screening efficiency is low, the working area is small, and the productivity is low. It is rarely used as screening equipment in concentrators.
The machine body swings or vibrates in a plane. According to its plane motion track, it can be divided into linear motion, circular motion, elliptical motion and complex motion. Shaking screens and vibrating screens belong to this category. During operation, the two motors are placed synchronously and reversely to make the exciter generate reverse exciting force, forcing the screen body to drive the screen mesh to make longitudinal movement, so that the materials on the screen are periodically thrown forward for a range by the exciting force, thus completing the material screening operation. The crank connecting rod mechanism is used as the transmission part of the shaker screen. The motor drives the eccentric shaft to rotate through the belt and pulley, and the machine body makes reciprocating motion along one direction through the connecting rod.

The movement direction of the machine body is perpendicular to the center line of the support rod or suspension rod. Because of the swing movement of the machine body, the material speed on the screen surface moves towards the discharge end, and the material is screened at the same time. Compared with the above-mentioned sieves, the shaking screen has higher productivity and screening efficiency.


Post time: Oct-17-2022