Jaw crusher is widely used in mineral processing, building materials, silicate and chemical industry because of its simple structure, reliable operation, easy fabrication, convenient maintenance, low equipment and production cost. It is generally used in the mineral processing industry for rough and medium - hard ore, and is sometimes used in other industrial and small mine production.
At present, the most widely used jaw crusher supplied by Sinonine has two structures: double-toggle jaw crusher and single-toggle jaw crusher. The former is made of medium or large, the crushing ratio is 3-6, the latter made small, the crushing ratio can reach 10. With the development of industrial technology, the pendulum type jaw crusher has been to large-scale development.
The specifications of the jaw crusher are given to the width of the ore mouth B and the length L. For example, the 900mmx1200mm jaw crusher, meaning B=900mm; L=1200mm.
Working principle of jaw crusher
Although the jaw crusher has a variety of structural types, the working principle is the same, that is to break the material through the periodic motion of the moving jaw. During the axially fixed jaw swinging in the center of the movable jaw, the material between the good jaw is subjected to crushing, splitting, and bending. At the beginning, the pressure is small, which makes the volume of the material shrink, and the material is close to each other. It is broken when the pressure rises to the strength that the material can bear. On the other hand, when the moving jaw swings from the fixed jaw to the opposite direction, the material moves down on its own weight. Each periodic movement of the moving jaw makes the material be crushed and down a distance. After a dry cycle, the broken material is discharged from the discharge port.
Structure of jaw crusher
The structure of jaw crusher is simple, which is mainly composed of frame, working mechanism, transmission mechanism, adjusting device, insurance device and lubricating system.
The jaw crusher has two kinds: the whole frame and the combined frame. The overall frame is usually welded by castings or steel parts. The medium and small crusher mostly use the whole frame. The combined frame is made up of a number of cast iron or weldments connected with a pin or bolt, which is mainly used for large jaw crusher with difficulty in transportation or processing and making.
The working mechanism of the jaw crusher is the crushing cavity, which is composed of the fixed jaw (the front wall of the frame) and the moving jaw . The two jaw plates are lined with manganese steel lined plates , and the lining plates are fixed on the jaw plate with bolts and wedges. As it is directly involved in breakage, to improve the crushing effect, the surface of the liner has longitudinal corrugation, and the concave and convex is relative. At present, the shape of the liner of the jaw crusher is mostly triangular and trapezoid two. Its surface is vertical straight.
Due to the uneven wear of all parts of the lining plate when broken, especially the location near the bottom outlet, the wear is the most serious. Generally, the liner is made up and down symmetrically, and it needs to be inverted after the lower part is worn to prolong its service life. The lining plate of the large crusher is made up of many blocks, and the blocks can be interchangeable, and the purpose is to prolong the service life.
The shape of the crushing chamber of the jaw crusher has a direct influence on its productivity, the composition of the grain size, the size of the grain, the life of the broken plate and the electricity consumption. At present, most of the crushing chamber of the large jaw crusher adopts the old straight line shaped cavity with all teeth. The cavity type is low in productivity, high in energy consumption, easily blocked, large and uneven in the size of the product. A lot of research work has been done on the crushing chamber at home and abroad, and a new type of cavity has been used in production. For example, the two cavities shown in a and b in Figure 3 have been used in the medium and small jaw crusher. It has been proved that the curve cavity has high productivity and large crushing ratio when the swing stroke and swinging times of the moving jaw are the same. The product has the advantages of uniform grain size, less comminution, less wear of the lower end liner of the crushing chamber and low energy consumption.
The eccentric shaft is supported in the spindle bearing on the side wall of the frame. The upper part of the connecting rod is installed in the eccentric position of the eccentric shaft. When the eccentric axis is driven by clicking, the connecting rod is driven up and down because of the eccentricity, thus driving the motion of the thrust plate. Because the thrust plate constantly changes its tilt angle when it moves, it drives the moving jaw to swing periodically around the suspension eccentric shaft , so as to achieve the purpose of crushing ore. In order to ensure the close combination of the moving jaw and the thrust plate, a tension device is usually made up of two pull rod and two spring . When the movable jaw is swinging, it can not only ensure that the moving jaw and the thrust plate are not separated, but also the inertia force produced by the moving jaw and the thrust plate can be partially balanced.
Because the work of the jaw crusher is periodic, it will inevitably make the load of the motor periodically change and cause the imbalance of the load. Therefore, the large crusher usually sets a flywheel at both ends of the eccentric shaft, and one of the flywheels is used as a pulley. According to the principle of inertia, the crusher can save energy when it is not working, and release it again when it works, so that the motor load is even.
The lining plate of the jaw crusher is constantly worn out by the ore at work, making the width of the discharge mouth widen gradually. In order to ensure the requirement of the grain size, the width of the discharge port must be adjusted in time. The following 3 kinds of regulating devices are commonly used.
A set of adjusting pad is placed behind the rear thrust plate support. When changing the number or thickness of the backing plate, the rear thrust plate or forward or backward can achieve the purpose of adjusting the width of the discharge port. The structure of this adjusting device is simple and compact and the weight of the whole machine is not much increased, so the large and medium jaw crusher is often used. The disadvantage is that it must be stopped when adjusting.
It uses a bolt or worm gear or chain transmission device to make the rear wedge lifting, and the front wedge is installed in the guide slot of the two side walls of the machine frame, so it can only move horizontally. When the rear inclined iron is lifted, because the inclined relation moves the front wedge forward along the guide slot, the thrust plate and the moving jaw move forward, and the width of the discharge port decreases. On the contrary, when the rear wedge drops, the width of the discharge mouth is increased. The advantage of this adjustment device is that it can be adjusted stepless, and it is not necessary to stop when adjusting. The disadvantage is that it is hard to adjust, and the size of the whole machine is increased, so it is suitable for small and medium jaw crusher.
This adjustment device uses hydraulic cylinder and cylinder plug to adjust the width of the discharge port, and use manual or electric hydraulic pump to supply oil to the hydraulic cylinder.
5） Sfety device
Due to the entry of machinery parts, iron or larger objects crushing cavity, or near the discharge port crushing chamber is jammed, the jaw crusher overload phenomenon. At this time the machine is rapidly increasing force, it is necessary to set up an insurance device to prevent the accidental damage of the crusher. The commonly used insurance devices are the following.
a）Thrust plate as an insurance device
In the design of the part, the thrust plate is designed to be the weakest link, when it is overloaded, it is broken first to protect the other parts of the equipment from damage. The thrust plate is not only the connecting rod of the transfer force, but also the safety part of the crusher. The thrust plate is usually made of cast iron, and the intercepting area is reduced by drilling or cutting in the middle. The thrust plate can also be used in combination . The rivet and other connecting elements are made of brittle materials, and they are first cut off when they are overloaded. This kind of insurance device is very simple, but the disadvantage is that after the accident, the treatment is more complicated and the time of shutdown is long.
b）Overload protection arm
The device mainly relies on the spring to connect the spindle of the belt and the crusher, and the torque is realized by adjusting the gasket according to the need. When the load is overloaded, the spring is removed from the pulley, and the pulley turns over the main axis, while the spindle stops turning, and it can be quickly reset when the overload is eliminated. The device is characterized by no damage to any part, and the safety is high, safe and reliable.Figure 7 the JC type jaw crusher is this structure.
c）Hydraulic connecting rod as an insurance device
In Figure 5, a hydraulic cylinder and a piston are attached to the connecting rod. The hydraulic cylinder is connected to the upper part of the connecting rod, and the piston is connected to the lower part of the connecting rod. In normal work, the hydraulic cylinder is filled with hydraulic oil, and the piston and the hydraulic cylinder are part of the whole connecting rod. In the case of overload, the pressure of the oil chamber in the lower part of the hydraulic cylinder increases due to the rapid increase of the tension on the connecting rod. When the oil pressure exceeds the pressure specified by the high pressure relief valve of the combined valve, the pressure oil is discharged through the high pressure relief valve, and the piston and thrust plate stop acting, and the movable jaw also stops swinging, thereby playing an insurance role. After the overload is eliminated, the crusher can continue to work after the hydraulic pump motor is started to add oil to the oil chamber under the hydraulic cylinder of the connecting rod.
The small jaw crusher usually adopts the rolling bearing, while the large and medium-sized Hubei crushing is generally used with the sliding bearing of the Babbitt bearing bush. Usually the bearing of the main bearing and the connecting rod head is cooled by circulating water when the bearing is overheated. The friction parts of the crusher are lubricated by dilute oil or dry oil. The bearings of the eccentric shaft and the connecting rod head are pressed into the dilute oil by the gear hydraulic pump for centralized circulation lubrication. The movable jaw bearing and the support pad of the lining seat are periodically pressed into the dry oil lubricated by a manual dry oil gun.
New type jaw crusher
The new type jaw crusher produced by Sinonine company is benefited from the rich experience accumulation and the large number of computer simulation and CAD design. Compared with the traditional type jaw crusher, it has the advantages of high strength, light equipment weight, high yield, low cost and so on.
1）More effective inlet
Compared with the traditional jaw crusher, our new jaw crusher has a more effective inlet . The jaw crusher reasonably designs the structure of the feed port. When the largest material enters, it will not be stuck. The large material entering the crusher can directly fall into the active area of the crushing cavity.
New type and traditional crushing chamber
2）Multiple alternative jaw plates
The standard jaw plate (type Z) is a flat corrugated surface with symmetrical upper and lower ends and can be turned over. Some materials require special types of jaw plates. There are many kinds of jaw plates for selection, such as NC (non crowded), Z type (symmetrical grid type), CC type (Rough corrugated type), WW type (wide corrugated type), etc.
NC non crowded type
Z symmetrical grid type
CC Rough corrugated type
WW wide corrugated type
3）The geometric design of the thrust plate; mechanism is combined with the running speed of the crusher to make the crusher get the maximum output and low wear. The ideal breakage angle ensures that the material moves through the crushing chamber downward and makes the crushing ratio reach the maximum.
Product graduation curve of Jaw crusher
Specification of Jaw crusher
Deep crashing cavity, no unreachable corner in cavity, higher feeding capacity and productivity.
Great crushing ratio, homogeneous output size.
Discharging adjustment by shim, reliable and convenient, broad range of adjustment, more flexibility.
Safe and reliable lubrication system, easy change spare parts, less effort in maintenance.
Simple structure, reliable work, low cost in operation.
Less energy consumption: single machine can reduce 15%-30% energy consumption, and the whole system can reduce by a half.
Broad range of discharging adjustment meets variable requirement of customers.
Low noise, little dust.
Powered by electrical motor, movable jaw is set in reciprocating movement at predetermined track through the transmission system of driving wheel, Vee-belt, and eccentric roll-driving shaft. The material is crushed in the cavity composed by fixed jaw plate, movable plate, and side protecting plate, and discharged the end product from the bottom discharge opening.This series jaw crusher adopts curve-movement compression way to crush the material. electric motor drives belt and belt wheel to set the movable plate in moving up and down through eccentric shaft. When the movable jaw rises, the angle formed by toggle and movable plate will be wider, and the jaw plate will be pushed approaching the fixed plate. In this way, the materials are crushed through compressing, grinding, and abrading. When the movable plate descends, the angle formed by toggle and movable plate will become narrower. Pulled by rod and spring, the movable plate will move apart from toggle, so the crushed materials can be discharged from the bottom of the crushing cavity. Consecutive movement of motor drives the movable plate in circular crushing and discharge to realize large-quantity production.