knowledge profile of shock absorber
damper vibration (shock absorber), mainly used to suppress the shock of the spring when the shock rebound after the shock and from the pavement. in the uneven pavement, although the suction spring can filter the vibration of the pavement, but the spring itself will have a reciprocating movement, and the shock absorber is used to suppress the spring jump. the shock absorber is too soft, the body will jump up and down, the shock absorber is too hard will bring too much resistance, impede the normal work of the spring.
working principle of automobile shock absorber
suspension system due to the shock vibration is produced by the elastic element, in order to improve the automobile driving comfort, suspension and the elastic element parallel installation of shock absorber, for the attenuation of vibration, vehicle suspension system with damper is hydraulic shock absorber and its working principle is when the relative motion of the frame (or body) and the bridge between the vibration, shock absorber piston moving, the damper cavity of the oil will repeatedly from a cavity through different pore into another chamber. at this time, the friction between the wall and the oil fluid and the internal friction between the oil and liquid molecules are damped, which causes the vibration energy of the vehicle to be converted to the oil heat energy, and then the shock absorber is absorbed and distributed to the atmosphere.. in the oil channel section and factors such as constant, damping force with the frame and axle (or wheel) between the relative motion speed increasing and with oil viscosity. the shock absorber and the elastic component are taking the task of the slow shock and shock, the damping force is too large, and the suspension elasticity will deteriorate, and even the shock absorber connector is damaged.. due to the contradiction between the elastic element and the shock absorber.
(1) in the compression stroke (vehicle axle and frame close to each other), shock absorber damping force is small, in order to give full play the elastic action of the elastic element, mitigate the impact. at this time, the elastic element plays a major role.
(2) in the suspension extension stroke (axle and frame away from each other), shock absorber damping force should be large, rapid vibration.
(3) when the axle (or wheel) the relative velocity between the axle and is too large, shock absorber can automatically increase the liquid flow, so that the damping force is always maintained within a certain limit, to avoid too to bear large impact load.
widely used in automobile suspension system is the shock absorber, and in compression and stretching stroke can play a damping effect is double action shock absorber, as well as the use of the new shock absorber, which comprises a shock absorber and resistance inflatable adjustable shock absorber.
the working principle of the two way cylinder type shock absorber is described. when the compression stroke, the car wheel is moved close to the body and the shock absorber is compressed, and the piston 3 moves down.. the volume of the lower chamber of the piston is reduced, and the oil pressure is raised, and the oil flows through the valve 8 to the piston in the upper chamber (upper chamber).. chamber piston rod 1 occupied part of the space and so on cavity increases the volume of less than inferior vena reduce volume and part of the oil liquid and then pushed compression valve 6 and flows back to the oil storage cylinder 5. the damping force of the suspension compression movement of the oil is saved by the valve.. the shock absorber in the expansion stroke, the wheel is equivalent to away from the body, the shock absorber under tension. at this time the piston of the shock absorber moves upward.. the piston chamber pressure increases, the circulation valve 8 is closed, the upper chamber oil pushing expanding valve 4 into the inferior vena cava. because of the existence of the piston rod, from the oil fluid cavity flow is not enough to fill a cavity increased volume, the inferior vena generates a vacuum, then the oil storage cylinder oil pushing compensation valve 7 into the vena supplement. because the valve of the throttle effect on suspension to play a damping effect in stretching exercises.
due to the expansion of the valve spring stiffness and preload design is larger than the compression valve, under the same pressure, stretch valve and corresponding changtong slit channel containing the area sum less than compression valve and the corresponding changtong slit channel cross-sectional area of the total. this makes the shock absorber damping force generated by the expansion stroke is greater than the damping force of the compression stroke, achieve rapid damping requirements.
classification of shock absorbers
the shock absorber is now used: 1 rubber shock absorber; 2 spring shock absorber; 3 air damper; 4 liquid air shock absorber; 5 full oil liquid shock absorber.
from the angle of the material, the shock absorber is divided into two kinds of hydraulic pressure and aeration, and a variable damping shock absorber..
structure of shock absorber
the structure of the shock absorber is a piston rod with a piston inserted into the cylinder, filled with oil in the cylinder.. the piston has a throttling hole, so that the piston can be separated from the space of the two parts of the oil can complement each other. the damping is generated during the flow of the oil through the flow of a viscous oil, the smaller the throttle orifice, the greater the damping force, the bigger the oil viscosity, the greater the damping force.. if the throttle hole size is constant, when the shock absorber is working fast, the damping will affect the shock absorption.. therefore, the set of a disk-shaped valve spring in the outlet of the throttling hole, when the pressure becomes larger, the top valve was opened, orifice opening larger, smaller damping. as the piston is a two-way movement, so are equipped with piston valve spring on both sides, which are called the compression valve and expanding valve.
the shock absorber can be divided into two - barrel and single - cylinder by its structure.. double tube type is shock absorber for both inside and outside the cylinder, piston, cylinder motion due to piston rod into and out of, inner cylinder oil volume increased with contraction. therefore, in order to through with the outer tube exchange balance to maintain the inner barrel of oil. so there are four valve in the shock absorber, that is, in addition to the above two throttle valve on the piston, there is also the exchange between the internal and external cylinder installed between the exchange of the valve and the valve.
compared with the double drum type, the structure of single cylinder type damper is simple, and a valve system is reduced.. it's in the cylinderthe lower part is equipped with a floating piston, (the so-called float refers to the absence of a piston rod to control its movement), and a closed chamber is formed under the floating piston, which is filled with a high pressure nitrogen. the height of the liquid caused by the piston rod is changed automatically by the floating piston.. in addition to the above two kinds of shock absorbers, there are resistance adjustable shock absorber. it can change the size of the orifice by external operation. recently, the car will be electronically controlled shock absorber as standard equipment, traveling through the sensor detection. by computer calculated optimal damping force of the shock absorber damping force adjusting mechanism to work automatically.
on the suspension system of the conversion process, the hard shock absorber to with hard spring matched, and weight is closely related to the hardness of the spring, so heavier vehicles generally use stiffer shock absorbers. the device with the crankshaft connecting the crankshaft, which is used to counter the torsional vibration of the crankshaft (i.e., the torsional phenomenon of the cylinder ignition of the crankshaft is twisted