Jaw crusher types and applications

The jaw crusher was invented by the American E•W•Blake (Blake). Since the first jaw crusher came out, it has a history of more than 140 years. In this process, its structure has been continuously improved.

There are two basic models of jaw crusher, namely simple pendulum jaw crusher and compound pendulum jaw crusher. Figure 1 shows the simple pendulum jaw crusher. Its working principle is: the motor 8 drives the belt 7 and the pulley 5, and the connecting rod 11 moves up and down through the eccentric shaft 6. When the connecting rod rises, the angle between the toggle plates 10 and 12 becomes larger, thereby pushing the movable jaw plate 3 to approach the fixed jaw plate 1, and at the same time, the material 2 is crushed; when the connecting rod goes down, the toggle plate 10 The angle between 12 and 12 becomes smaller, and the movable jaw leaves the fixed jaw under the action of the pull rod spring 9. At this time, the crushed materials are discharged from the crushing chamber. With the continuous rotation of the motor, the mobile jaw is broken to periodically crush materials. This kind of crusher is called simple pendulum jaw crusher because the movable jaw simply swings around the suspension point. The machine is a crank double rocker mechanism. The trajectory of the movable jaw swinging around the suspension axis is a circular arc.

Remove the suspension shaft of the simple pendulum crushing mobile jaw, and suspend the movable jaw on the eccentric shaft. At the same time, remove the front toggle plate and connecting rod to form a compound pendulum jaw crusher, as shown in Figure 2. Because the mobile jaw rotates around the eccentric shaft, it also swings around the same center, forming a complex movement, so it is called a compound pendulum jaw crusher. The machine is a crank connecting rod mechanism, and the moving jaw movement track is a connecting rod curve, which is regarded as an ellipse.

Comparing these two types of crushers, the former has the advantage that the vertical stroke of the movable jaw is small, which makes the liner wear light; in work, the connecting rod exerts a small force while the toggle plate can generate a large thrust; its disadvantages are: structure It is more complex and heavier, 20% to 30% heavier than the crusher of the same specification; secondly, its moving jaw movement track is not ideal, the upper horizontal stroke is small and the lower horizontal stroke is large. The material distribution in the crushing cavity is as follows: the upper cavity has a larger material block and the lower cavity has a smaller material block. The large block requires a larger crushing stroke while the small block is just the opposite. If the requirements for bulk materials are met, the horizontal stroke of the discharge opening is too large, and the product size cannot be guaranteed. In addition, the movable jaw has the effect of obstructing the discharging in the process of crushing the material. Therefore, under the same conditions, it is about 30% lower than the productivity of the compound pendulum crusher. With the improvement of the quality of rolling bearings and the wear resistance of wear-resistant materials and the adoption of modern design methods to reduce the wear of the liner, the compound pendulum jaw crusher has basically replaced the simple pendulum jaw crusher. The largest domestic specifications include 1500×2100 compound pendulum jaw crushers and 1800×2100 and 2000×3000 compound pendulum jaw crushers abroad.

At present, from the domestic and foreign markets, most of them are compound pendulum jaw crushers. This type of crusher should be vigorously developed. Due to its simple structure, easy manufacturing, reliable work, and convenient maintenance, jaw crushers are widely used in metallurgy, mining, building materials, chemical, coal and other industries. In coarse crushing operations, jaw crushers mainly compete with gyratory crushers. If it can meet the output requirements, it is generally appropriate to choose a jaw crusher; when the output is large, consider choosing a gyratory crusher. In terms of medium and fine crushing, jaw crushers are mostly selected for small output. Otherwise, choose a cone crusher.

Feeding mouth width greater than 600mm is a large-scale crusher, feeding mouth width 500-600mm is a medium-sized crusher, and feeding mouth width is less than 500mm is a small crusher. The jaw crusher has a crushing ratio of up to 10.