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What is the car suspension is better — SP educational program

What to prefer, soft or rigid, dependent or independent? The answer is simple — the one that you like, but one that has equipped this car model developers.

‘Madam, why, let me ask you, are you not wearing diamond studs? After all, you knew that I would love to see them on you. A. Dumas “the Three Musketeers”

Recall: suspension of the car is called the totality of the parts connecting the body or frame of the car with the wheels.

Here are the main suspension components:

  • The elements for the elasticity of the suspension. They perceive and transmit the vertical forces which arise when passing irregularities in the road.
  • Guide elements — they determine the nature of the movement of the wheels. Also the guide members transmit longitudinal and lateral forces and the resultant of the forces moments.
  • The cushioning elements. Designed for damping oscillations arising at influence of external and internal forces

The first was the spring

The first wheel had no suspension elastic elements are simply missing. And then our ancestors probably inspired by the design of small onions, began to use springs. With the development of metallurgy the steel bands have learned to give elasticity. Such bands are collected in the package, and formed the first sprung suspension. Then I often used the so-called elliptic suspension, when the ends of the two springs were connected, and their middle is attached to the body with one hand and to the axis of the wheels on the other.

The first wheeled vehicles with no suspension was not.The first wheeled vehicles with no suspension was not.

And on the front and rear axles apply the classical elliptic leaf springs.And on the front and rear axles apply the classical elliptic leaf springs.

Then the springs began to be used on cars, and as a semi-elliptical design for conventional suspensions, and installing one or two springs across. When it got independent suspension. The domestic auto industry has long used springs on the Muscovites before the advent of front-wheel drive models, on the Volga (with the exception of the Volga Siber) and the Lite springs are used so far.

Everyone who has ever used the services of taxis on the basis of a GAZelle, was in a car with a fully spring suspension. The leaves in the leaf springs a bit or two on the front axle and three on the back.Everyone who has ever used the services of taxis on the basis of a GAZelle, was in a car with a fully spring suspension. The leaves in the leaf springs a bit or two on the front axle and three on the back.

Spring has evolved along with the car: the spring blades became smaller, including the use of a single sheet of spring on modern small delivery vans.

The advantages of spring suspension

Cons spring suspension

  • Simplicity of design — dependent suspension with only two leaf springs and two shock absorbers. All forces and moments from wheels spring transmits to the body or frame, without the need for additional elements
  • Compact design
  • Internal friction in the spring with a few leaves dampens the oscillations of the suspension system that reduces the need for shock absorbers
  • Ease of fabrication, cheapness, maintainability
  • Typically used in dependent suspension, she now found less
  • High enough weight
  • Not a very high durability
  • Dry friction between the sheets or requires the use of special gaskets or periodic lubrication
  • Tough construction with springs is not conducive to comfort at low load. So often used on commercial vehicles.
  • Characteristics adjustment operation is not provided

Spring suspension

Spring began to set at the dawn of the automotive industry and successfully used until now. The springs can operate in the dependent and independent suspensions. They are used in cars of all classes. The spring is initially cylindrical, with a constant step of coiling the improved suspension design has acquired new properties. Now apply a conical or barrel-shaped springs are wound from a rod of variable cross section. All in order for the force to grow is not directly proportional to strain, and more intense. First, work areas of larger diameter, and then exclude those that are smaller. Similarly, the thinner the rod comes into operation sooner than the thicker.

On a modern small car in the front is most often used suspension type “swinging candle” with the springs complex profile.On a modern small car in the front is most often used suspension type “swinging candle” with the springs complex profile.

Rear suspension semi-affordable cars is almost uncontested applies a spring.Rear suspension semi-affordable cars is almost uncontested applies a spring.

The advantages of spring suspension

Cons suspension

  • Proven and low-cost design
  • Relatively high durability
  • The possibility of progressive features
  • Maintenance and lubrication
  • Suspension is not very compact, since the spring may not transfer any effort, in addition to axial, and therefore require guide elements in the form of levers.
  • Spring suspension does not have the property of damping, and therefore require powerful shock absorbers
  • No possibility to change characteristics of the suspension

Torsion bars

Did you know that almost any vehicle with spring suspension still have torsion bars? Because the stabilizer bar, which is now put almost everywhere, it is torsion. In General, any relatively straight line and a long lever, the torsion, is a torsion bar. As the main elastic elements of the suspension torsion bars were used along with springs at the beginning of the automotive era. The torsion bars were set along and across the vehicle, used in a variety of types of pendants. On domestic cars the torsion bar used in the front suspension of the Cossacks several generations. Then torsion bar suspension had by the way as a result of its compactness. Now often use torsion bars in the front suspension frame SUVs.

An example of installation of the torsion bars in the front suspension Great Wall Hover.An example of installation of the torsion bars in the front suspension Great Wall Hover.

The elastic suspension member is a torsion steel rod working in torsion. One end of the torsion bar fixed to the frame or the carrier vehicle with the ability to adjust the angular position. At the other end of the torsion bar is set lower front control arm. The force on the lever creates a moment, twisting the torsion bar. Neither longitudinal nor lateral forces on the torsion does not act, it works in pure torsion. Tightening torsion bars can be adjusted the height of the front of the car, but with full suspension travel remains the same, we only change the ratio between compression strokes and rebound.

On the rear ends of the torsion bars mounted levers, allowing to adjust the preload.On the rear ends of the torsion bars mounted levers, allowing to adjust the preload.

The advantages of torsion bar suspension

Cons torsion bar suspension

  • Very compact and lightweight
  • It is possible to regulate the preload of the torsion, which allows you to retune the suspension for your specific needs
  • In case of breakage, which is rare, easy to replace on their own. Also simplified the fixation of the front suspension, you can always unload just loosening the torsion bars.
  • Very high demands on manufacturing quality, since the torsion is not just a bar, and requires a durable sealing of the ends, typically using splines.
  • Relatively expensive to manufacture

Dampers

From school physics course known that any elastic system characterized by oscillations with a certain frequency. And if more will affect the exciting force with the same frequency, there is resonance — a sharp increase of vibration amplitude. In the case of a torsion or spring suspension to deal with these fluctuations and called dampers. Hydraulic shock dissipation of the vibration energy is due to the energy loss for pumping a special fluid from one chamber to another. Telescopic shock absorbers are now ubiquitous, from small cars to heavy trucks. The shock absorbers, called the gas, actually a liquid, but in a free scope, and he is all shock absorbers, contains not just air, a gas under high pressure. So the “gas” shock absorbers always strive to push your rod outside. But following suspensions without shock absorbers can do.

Air suspension

In the pneumatic suspension the role of the elastic element plays the air trapped in the closed space of the air. Sometimes instead of air using nitrogen. The bellows is a sealed container with walls of synthetic fibers, which are embedded in vulcanised layer sealing and protective rubber. The design is reminiscent of the sidewall.

The most important quality suspension is the ability to change the pressure of the working fluid in the cylinders. Moreover, the pumping of the air allows the device to play the role of shock absorber. The control system allows to change the pressure in each cylinder. Thus buses you can politely bend over at the bus stop to facilitate boarding of passengers, and trucks to maintain a constant “becoming”, being stuffed to the eyeballs or completely empty. And passenger car air springs can be installed in the rear suspension to maintain a constant ground clearance depending on the load. Sometimes the design of the SUV used air suspension on the front and rear axles.

Front air suspension of the Audi Q7 SUV.Front air suspension of the Audi Q7 SUV.

Air suspension allows you to adjust the ground clearance of the car. At high speeds the car “squats” closer to the road. Since the center of mass becomes lower, decreases valkosti in the turns. And on the roads where high clearance body, on the contrary, rises.

Pnevmoelementy combine the functions of spring and damper, but only in cases if it is a factory design. The tuning structures, when the air springs simply add to the existing suspension, shock absorbers better to leave.

The advantages of air suspension

Cons of air suspension

  • Low weight
  • The ability to change stiffness
  • Maintaining a constant clearance
  • The possibility of changes in clearance
  • Replace the elastic and damping elements
  • High complexity and cost of the entire system
  • On passenger cars and off-road durability lower than that of other types of pendants.

Installation pneumatisk love tuninvest of all stripes. And, as usual, someone wants it lower, someone higher.

Air suspension monster truck.Air suspension monster truck.

Tuning pneumococci, which are designed to replace traditional dampers with spring.Tuning pneumococci, which are designed to replace traditional dampers with spring.

Air suspension on the prepared SUV. Suspension travel downwards is limited by a strap.Air suspension on the prepared SUV. Suspension travel downwards is limited by a strap.

Dependent and independent suspension

Everyone has heard the expression “he’s got independent suspension in a circle”. And what does it mean? Independent suspension is a suspension where each wheel makes moves the compression and rebound (up and down) without affecting the movement of other wheels.

Independent front suspension torsion bar type is most often used on SUVs.Independent front suspension torsion bar type is most often used on SUVs.

Independent rear suspension is used ranging from C-class to the most complex and expensive Executive cars.Independent rear suspension is used ranging from C-class to the most complex and expensive Executive cars.

Independent suspension is MacPherson type with L or A-shaped levers today the most common type of front suspension in the world. The simplicity and cheapness of construction are combined with good handling.

Independent front suspension L-shaped control arms and MacPherson struts (McPherson).Independent front suspension L-shaped control arms and MacPherson struts (McPherson).

Dependent called such a suspension when the wheels share one hard beam. The one wheel, for example up, is accompanied by a change of the angle of inclination of the other wheel on the road.

Rigid rear axle beam suspended to a frame on five rods.Rigid rear axle beam suspended to a frame on five rods.

Before such suspension was used very widely — at least take our Lada. Now just for the serious off-roader with a powerful continuous beam rear axle. Dependent suspension is good only for its simplicity and is used where in terms of strength tough solid axle. There are still semi-suspension. This is used on the rear axle of inexpensive cars. It is an elastic beam, which connects the axis of the rear wheels.

Rear semi-suspension due to the simplicity, low cost and good characteristics, widely distributed.Rear semi-suspension due to the simplicity, low cost and good characteristics, widely distributed.

Semi-suspension provides a relatively good performance, is much cheaper independent. But the independent suspension — Queen of hangers — ensures optimal grip of each wheel with the road and the least transmission of shocks from irregularities in the car body. Thus such a design is the most expensive to maintain.

You softer?

What to prefer? Soft or hard? Answer is very simple — the one that you like, but one that has equipped this car model developers. Choose a car when buying on the scale “Hard — Soft” and do not try to improve the design after purchase. Shocks from different manufacturers have a different fame in the market: some are tougher, others are softer. But the manufacturer directly never you will not tell about it. The box will be shown, apply this absorber to your car or not.

Another method which is acceptable to slightly change the stiffness of the suspension is the tyres the higher or the lower profile of the range permitted by the manufacturer. Read about it here.

Conclusion

Each suspension type has found its niche and a good feel there, continuing to develop gradually. Perhaps experts in the field of internal combustion engines will be unemployed before podvizhniki! But seriously, is considered the most advanced air suspension. While its disadvantage is the complexity of the design and the price. But over time, if you do not invent anything new, then independent suspension is the future. And try to keep the suspension in good condition. Do not drive with empty absorbers, curved levers and a spring, from which “just one round with the edge broke off”.

Write in the comments what type of suspension do you prefer and why.

What is the car suspension is better — the educational program SP of thePhoto: “Behind the wheel” and from the author’s archiveWhich suspension is better — SP educational program

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