Classification of jaw crushers

As far as jaw crushers are concerned, although the structural types are different, their working principles are basically similar, except that the motion trajectories of the moving jaw are different. In a word, when the movable jaw plate makes periodic reciprocating motion to the fixed jaw plate around the suspension axis, sometimes approaching and sometimes leaving, just when the movable jaw plate approaches the fixed jaw plate, the ore between the two jaw plates is crushed by the combined action of crushing, splitting and bending and breaking; When the movable jaw leaves the fixed jaw, the crushed ore is discharged through the ore discharge port of the crusher under the action of gravity.

Single pendulum jaw principle

The movable jaw is suspended on the spindle and can swing left and right. When the eccentric shaft rotates, the connecting rod reciprocates up and down, driving the two thrust plates to reciprocate, so as to push the moving jaw to reciprocate left and right, so as to realize crushing and unloading. This kind of crusher adopts a crank double connecting rod mechanism. Although there is a great crushing reaction force on the moving jaw, the eccentric shaft and connecting rod bear little force, so it is mostly made into large-scale machines and medium-sized machines in industry to crush hard materials. In addition, when this crusher works, the motion track of each point on the moving jaw is an arc centered on the mandrel, and the radius of the arc is equal to the distance from the point to the axis. The upper arc is small, the lower arc is large, and the crushing efficiency is low. Its crushing ratio is generally 3-6. Because of the simple movement track, it is called simple swing jaw crusher.

The simple pendulum jaw crusher has a compact and simple structure, and the eccentric shaft and other transmission parts are less stressed; Due to the small vertical displacement of the movable jaw, there is less excessive crushing of materials during processing, and the wear of the movable jaw plate is small.

Jaw principle of compound pendulum

The upper end of the movable jaw is directly suspended on the eccentric shaft. As the connecting rod of the crank connecting rod mechanism, it is directly driven by the eccentricity of the eccentric shaft. The lower end of the movable jaw is hinged with the thrust plate and supported on the rear wall of the frame. When the eccentric axis rotates, the motion trajectory of each point on the movable jaw gradually changes from the circumference of the suspension point (the radius is equal to the eccentric distance) to an ellipse. The more it moves towards the lower part, the more the ellipse deviates until the trajectory of the connecting point between the lower part and the thrust plate is a circular arc. Because the motion trajectory of each point on the moving jaw in this machine is relatively complex, it is called complex swing jaw crusher.

Compared with the simple pendulum jaw crusher, the compound pendulum jaw crusher has the following advantages: lighter weight, fewer components, more compact structure, better filling degree in the crushing cavity, the loaded material blocks are evenly crushed, and the finished products are forcibly unloaded at the lower end of the movable jaw, so the productivity is higher, which is 20-30% higher than that of the simple pendulum jaw crusher of the same specification; The material block has a large up and down rolling movement at the lower part of the movable jaw, which is easy to unload out of the jaw crusher in the shape of a cube

Jaw crusher is mainly composed of fixed jaw plate, movable jaw plate, frame, upper and lower guard plates, adjusting seat, movable jaw pull rod, etc. A good understanding of the internal structure of jaw crusher can play a good role in helping jaw crusher in the process of use and in case of problems.

Crushing ratio

Crushing ratio is an important evaluation index to measure jaw crusher. The crushing ratio of jaw crusher is the ratio of raw material particle size to the accuracy of crushed products. It indicates the reduction of raw materials after crushing. After the ore is crushed, the particle size becomes smaller. The ratio of the particle size before the ore is crushed to the particle size after crushing is called the crushing ratio. It represents the multiple of particle size reduction after ore crushing. The calculation methods of crushing ratio are as follows:

1. The maximum particle size method is calculated by the maximum particle size before ore crushing and the maximum particle size after crushing. This calculation method is often used in the design of concentrators in China, because the width of the ore feeding mouth of the jaw crusher should be determined according to the maximum particle size of ore feeding in the design

2. Use the ratio of the effective width of the feed port to the width of the discharge port of the jaw crusher. The discharge particle size of some jaw crushers is not determined by the size of the discharge port.

3. It is calculated by the average particle size before and after ore crushing, also known as the average crushing ratio

characteristic

1. Low noise and less dust.

2. Its crushing ratio is large and the particle size of the product is uniform.

3. Simple structure, reliable operation and low operation cost.

4. The lubrication system is safe and reliable, the parts are easy to replace, and the equipment maintenance is simple.

5. The crushing cavity is deep and has no dead zone, which improves the feeding capacity and output.

6. Energy saving of equipment: energy saving of single machine is 15% - 30%, and energy saving of system is more than twice.

7. The discharge port has a large adjustment range, which can meet the requirements of different users.