The torsion bar is a metal elastic element that works on twisting. As a rule, this is a metal rod of round section with a slotted connection at the ends. The torsion can consist of a set of plates, rods, beams of a certain section. Structurally, the torsion bar is attached at one end to the body or frame of the car, and at the other - to the guide element - the lever. When the wheels are moved, the torsion bar is twisted, which achieves an elastic connection between the wheel and the body. A feature of torsion bars is rotation in only one direction - in the direction of twisting. Another feature is that the torsion bar can be used to adjust the body height. Torsion bars are used in various types independent suspensions: on double transverse levers, on longitudinal levers, with connected longitudinal levers (torsion beam).
In a torsion bar suspension on double wishbones, the torsion bars are parallel to the body, so that their length and, accordingly, the elastic properties can be adjusted over a wide range. One end of the torsion bar is attached to the lower transverse arm (rarely to the upper arm), the other end to the vehicle frame. This torsion bar suspension design is used as front suspension passenger cars off-road vehicles - some models of American and Japanese SUVs. In a trailing arm torsion bar suspension, the torsion bars are connected to the trailing arms and, accordingly, are located across the body. This torsion bar suspension design is used as rear suspension some models cars small class. A special place in the designs of torsion bar suspensions is occupied by the so-called. torsion beam or trailing arm suspension. The guiding device of this suspension are two trailing arms rigidly interconnected by a beam. The trailing arms are attached to the body on one side, and to the wheel hubs on the other. The beam has a U-shaped section, so it has high bending rigidity and low torsional rigidity. This property allows the wheels to move up and down independently of each other. torsion beam currently widely used as a rear suspension front wheel drive vehicles small and middle class. Due to its design, the torsion beam suspension occupies an intermediate position between the dependent and independent type of suspension, which is why its other name is semi-independent suspension.
History of appearance
Torsion suspension began to be used since the mid-1930s on cars of the French brands Citroen. In the 1940s, torsion bars were used on racing cars Porsche. Subsequently, they were used by many other automakers. For example, Renault, ZIL and Chrysler. The use of torsion bar suspension was primarily due to good performance smooth running and simple design.Types of torsion suspensions
Front independent torsion bar suspension on wishbones The front torsion bar suspension on wishbones (one or two depending on the design) consists of the following elements: Longitudinally located torsion bar, working on twisting and replacing the spring. The lower or upper arm that takes the main load, through which the force is transferred to the torsion bar. The damping element is a shock absorber that performs the function of damping vibrations. Stabilizer roll stability compensating for body roll while driving. The compactness of the front torsion bar suspension on the wishbones allows efficient use of free space. For example, to install massive wheel drives. In this regard, torsion bars have become widespread in the production frame SUVs combining cross-country ability with the softness of the suspension. For example, Toyota Land cruiser 100 (mounting the torsion bar to lower arm) And Toyota Hilux Surf (torsion bar on upper arm). Torsion bars are also used on the front axle of commercial vehicles.Rear independent suspension with transverse torsion bars
In the designs of rear suspensions with a longitudinal arrangement of levers, torsion bars are installed transversely. Legendary French Renault car 16, which was produced until the 1990s, was equipped with a front suspension with longitudinally located torsion bars, and a rear suspension with a transverse one. feature elastic elements rear suspension was their location - one was behind the other, which structurally entailed a difference in the wheelbase on the sides of the car (one of the wheels was several centimeters closer to the front). The handling and stability of the car left much to be desired, however, it was the compactness of the torsion bar suspension that made it possible to significantly increase the volume luggage compartment, which largely determined the popularity of the model. Currently, such a suspension scheme is not used by automakers.Semi-independent rear torsion beam
Semi-dependent U-shaped torsion beam, which has an integrated elastic rod, becomes more bending strength. At the same time, it allows the wheels of one axle to move slightly relative to each other when driving through bumps. This improves the handling and stability of the car. This suspension is used on rear axle most budget front-wheel drive cars.Benefits of torsion bar suspension
✔ High running smoothness. ✔ Compact and light weight. ✔ High maintainability. ✔ Simple and reliable design.Disadvantages of torsion bar suspension
✔ The complexity of the production of torsion bars. ✔ Mediocre car handling. Currently, the front independent suspension, where torsion bars are installed as elastic elements, is used in the production of trucks and SUVs that are not designed for dynamic driving. In addition, the torsion bar suspension is successfully used in tank chassis designs and other special tracked vehicles.READ ALSO ON THE SITEWe all understand that a braking system is necessary for safe operation any vehicle. Leading culprit of failure brake system on older cars, trucks and SUVs is vacuum booster brakes. ... The Chevrolet Niva fuse box is located to the left of the steering column and is closed with a lid from below. To get to it, you need to screw in 2 screws, after wringing out the upper edge of the cover, gradually release it from all fasteners. ... injection system diesel fuel has undergone many changes over the years. When people think of the word "diesel", most people think that huge trucks emit a lot of black soot and smoke, which cause great harm environment. However... |
The main element of the torsion bar suspension is the torsion bar, which is a cylindrical metal rod,. In order for the torsion bar to spring well when twisting, it is made of durable steel that has undergone special heat treatment. At the same time, it withstands high mechanical torsional stresses and allows large twisting angles without permanent deformation. Torsion rods can have a round or square section, and also consist of metal plates.
Torsion suspension device
At one end, the torsion beam is rigidly fixed to the vehicle frame, and its other end is connected to the wheel hub through a lever. Vertical movements wheels lead to twisting of the torsion bar and the appearance of a springy reaction. Thus, a strong and elastic connection of the car body with it is ensured. To increase the reliability of the connecting nodes and protect against shock overloads, additional spiral springs and are used. Such a suspension system was widely used until recently in many types of vehicles.
How torsion bar suspension developed
The modern torsion bar suspension system found on today's vehicles is the result of a large number improvements to the part that was used for the first time on a car Volkswagen Beetle, which appeared in the 30s of the 20th century. The Czech scientist Ledvinka was the first to modernize the torsion bar and apply it on cars brands Tatra in the same 30s. Already in 1938, the similarity of the Ledwink torsion bar began to be massively used in the KdF-Wagen car company Ferdinand Porsche.
The famous Austrian engineer quickly appreciated the main thing - its low weight, which is so necessary and in demand in the army and sports cars as well as SUVs. Where there are strict requirements for the weight and dimensions of the car. And at present, this advantage of the torsion bar suspension is relevant and effective, as evidenced by their use on such heavyweights as the Ferrari F2001, Toyota Landcruiser, MAZ-547, etc. Ferdinand Porsche also developed torsion bars with double levers, the transverse rods of which were placed in steel pipes, located one above the other and played the role of a torsion beam.
French engineer André Lefebvre, constructor Citroen car TA, used such a virtue of the torsion bar as the dependence of the stiffness of the suspension on the length of the torsion beam. The longer the torsion bar, the softer the suspension. In addition, a long shaft, located along the longitudinal axis of the car, allows you to distribute the dynamic load received from the roadway over its entire frame. This improves the stability and controllability of the machine.
During the Second World War, torsion bars were actively used in armored and automobile military equipment. The torsion bar suspension was installed on the German "Panthers" and the Soviet "KV". Having successfully passed tests in combat conditions, these pendants became widespread in the post-war period. They were used by almost all car manufacturers in Europe and America. And 1961 is significant in that the torsion bar was first used on the front suspension. This car has become Jaguar E-Type. In America, such a suspension was used on Chrysler and Packard cars, and in the Soviet Union they were installed on ZILs, LUAZs and Zaporozhets.
Advantages and disadvantages
The location of the torsion beam under the body can be either longitudinal or transverse. For the most part, the longitudinal arrangement is used on large and heavy vehicles. On passenger vehicles more commonly used are compact transverse torsion bars of the rear suspension. In both cases, the suspension is designed to solve the following tasks:
- maximum absorption of mechanical vibrations of the wheels and frame;
- stabilization of the position of the steered wheels;
- cornering angle adjustment.
The transverse suspension is limited in length by the machine's track width. On the sides of the body, the working ends of the transverse torsion bars are connected to suspension arms. Therefore, the softness of such pendants is also limited. Unlike transverse longitudinal beams, they do not have strict length restrictions, therefore, in terms of softness, such suspensions are not inferior to springs and springs. In addition, the longitudinal design of the suspensions creates additional technological conveniences when assembling the body of large cars.
The main advantages of torsion bar suspension include the following:
- it is more compact compared to the spring system and takes up much less space;
- ease of installation and maintenance;
- light weight;
- it allows you to easily and quickly install the necessary ground clearance without changing the details of the suspension design;
- high reliability and maintainability;
- long service intervals and ease of adjustment;
- it provides better handling vehicle in the event of a roll.
All maintenance of the torsion bar suspension basically comes down to tightening mounting bolts, which can be done with only . However, you should not use the principle “the stronger, the more reliable” in this case, since excessive tightening of the bolts can cause increased suspension stiffness.
torsion bar suspension, except heavy vehicles used in the production of passenger cars. Example: Toyota Corolla Fielder, where a rear torsion bar is used.
The main disadvantages of suspensions on torsion beams are:
- The tendency of a car with such a suspension to oversteer. When cornering, such cars begin to turn around, which requires increased attention from the driver. Such a tendency is most characteristic and noticeable on ZAZ cars, which are small in size.
- Sophisticated technology for the production and processing of torsion bars, providing the necessary high strength and elasticity of the material. To ensure the resistance of the metal to the occurrence of surface cracks, torsion bars undergo special surface hardening procedures using plastic deposits and other technologies. All these technological operations increase the cost of the suspension. Despite this, they find application in modern automotive technology to provide them high level comfort when driving on various types of road surfaces.
- The presence of needle bearings in the attachment points of the levers to the ends of the torsion beam with a limited mileage resource. Bearings tend to fail due to dust, water and dirt entering through cracks in seals and gaskets. Moreover, this happens more often due to the aging of the rubber material and exposure to aggressive environments than from driving style and its intensity. The main panacea for this trouble is to often look under the bottom of the car. Timely Service will allow you to replace the seals or bearings. In the worst case, the beam will have to be repaired or replaced, as the failed bearings flare the seats, which leads to a change in the camber. The resource of bearings is from 60 to 70 thousand km.
One of the reasons that limit the use of torsion bars is the difficulty of obtaining fully independent wheel suspensions that provide a high level of comfort. However, the presence of a torsion beam makes it possible to obtain sufficiently free suspensions if rotating beams are used at the ends. This achieves greater independence of the wheels and greater smoothness when driving. This suspension is especially effective on heavy vehicles such as the Peugeot 405 and Renault Laguna, in which it experiences a greater load, which contributes to an improvement in ride comfort. On lighter Peugeot cars 106, 206, 306 such suspension will be less efficient and comfortable.
With the development of production technologies over time, torsion systems ceased to be used in passenger transport due to the high cost of manufacturing torsion beams and the specifics of operation passenger cars. Now they are used in most cases on trucks and SUVs from companies such as Dodge, General Motors, Mitsubishi Pajero, Ford.
Greetings, my dear motorists! In this article, we have to find out: what is a torsion bar suspension, the principle of operation of this design and its features.
If you dig deeper into history, it turns out that the torsion bar suspension was successfully used at the beginning, middle and end of the twentieth century, and is also often found today.
Having undergone a lot of upgrades and improvements during its existence, it has become a classic, and you can see it not only on passenger cars, but even as a tank suspension.
In fact, the design of the torsion bar suspension can be different, which we will discuss later. But be that as it may, the key element of the system is the so-called torsion (elastic element), hence the name.
What is this? In fact, this is a metal rod, which can have both a round and a square section.
The main property of the torsion bar is its high torsional elasticity, i.e. if you take such a rod by its two ends and twist it in opposite directions, then it will naturally spring and try to return to its original state. This property is the basis for the operation of torsion bar suspensions..
Without problems from the XX to the XXI century
A bit of history. As we said at the beginning of the article, this type of pendant did not appear yesterday. More precisely, in the 30s of the twentieth century, the legendary Volkswagen Beetle became the first car with a similar design. lucky engineering solution noticed and adopted in the same years and Ferdinand Porsche.
Then, during World War II, torsion bars proved indispensable in armored vehicles, and such a suspension was used in both Soviet and German cars.
In the post-war years, similar systems became a real hit - they were and remain in service with almost all major automakers in the world.
It's time to talk about performance options. Torsion suspension, the principle of which is based on twisting, can be found in the following designs:
- on double wishbones;
- on trailing arms;
- with associated trailing arms or the so-called torsion beam.
The first two types are independent suspensions. In case of wishbones torsion bars are installed parallel to the body.
This positioning allows you to adjust the softness of the system over a wide range - the longer the rod, the softer the stroke. It is attached on one side to the upper or lower arm, and the second to the car frame.
This design is used, as a rule, on the front axle of SUVs and crossovers. For example, on the Mercedes M-class of the 163rd series.
In a suspension with trailing arms, the torsion bars are located transversely to the body and are also fixed at one of the ends to the levers. It is worth noting that this option is common on the rear axle of various small cars.
Torsion suspension the principle of operation of which, as we know, is based on twisting, refers to the so-called semi-dependent suspensions. The wheels on the axle are rigidly connected to each other, but at the same time they have the ability to move up and down separately.
The system is based on a torsion beam connecting the trailing arms of each wheel (there are two such arms in total). You can meet it in cars on the rear axle.
Two sides of the torsion bar suspension medal
Like any other, torsion bar suspension has its pros and cons. TO positive aspects systems unequivocally refer to its simplicity, low weight and compactness, and a small number of parts leads to reliability and ease of maintenance.
But there is also flaws. For example, the worst controllability of cars compared to cars with multi-link designs, difficulties in the production of reliable elastic elements, as well as increased wear needle bearings, which are installed at the joints trailing arms and torsion beam.
I hope, friends, that this material, the torsion bar suspension principle of operation, was useful to you. I advise you to read more articles about the suspension - and the car
Don't forget to stop by the light to continue exploring the insides of cars with us.
Until future meetings!
Let's define what is car suspension. This is a device that provides elastic coupling car wheels with a carrier system, as well as regulating the position of the body when driving, reducing the load on the wheels.
Currently offered Various types suspensions: spring, pneumatic, spring, torsion, etc. So, the torsion type is torsion shafts made of metal that work in torsion, with one end attached to the chassis, the other to a special lever standing perpendicular and connected to the axle.
The manufacture of such a part is made of heat-treated steel, which directly allows to withstand heavy loads at the moment of rotation.
The main principle of the suspension is bending work.
Application of the torsion model
The location of the torsion beam is possible longitudinally and transversely. The longitudinal arrangement is used on large, heavy trucks. On passenger cars, a transverse arrangement is used, usually on a rear-wheel drive.
In these two cases, the mechanism is designed to ensure smooth running, control roll when turning, ensure the optimal damping of vibrations of the wheels, the body, and reduce vibrations of the steered wheels.
For some vehicles, torsion bar suspension is used for automatic leveling, using a motor to tighten the beams for added rigidity, depending on speed as well as road surface conditions.
Adjustable height design can be used when changing wheels. It is when vehicle lift with three wheels, and the 4th is lifted with a jack. The main advantage of this type of suspension is durability, ease of height adjustment, as well as compactness in the width of the vehicle.
It takes up much less space than spring suspensions. Of course, the torsion bar configuration is easy to operate and also easy to maintain.
Work process
From this video, you will learn how the torsion bar suspension works.
Thanks to torsion shaft it is fixed rigidly on the body or frame of the car; during the operation of the suspension, twisting forces act on it. But the torsion shaft is made of a special alloy and has a certain hardening, which allows it to work as a spring element.
At the moment of twisting, the shaft tends to return car wheel to original position. So, the principle of operation is similar to a spring or sprung version of this auto part. Semi-independent suspension is a suspension system made in the form of two trailing arms connected by a cross member of the trailing arms.
The main advantages of such a mechanism:
- ease of installation;
- light weight;
- compactness.
The key disadvantage is the possibility of application only on a non-driving axle.
suspension adjustment
In the case of a loose suspension, it is possible to adjust the positions using an ordinary wrench. It is enough to get down the car, tighten the necessary bolts. The main thing is not to overdo it in order to avoid excessive rigidity of the stroke at the moment of movement. Torsion parts are easier to adjust than spring types.
Car manufacturers are changing the torsion beam to control the position of the movement, depending on the weight of the engine.
Key repair properties
Considering all the problems of torsion beams, it is quite possible to conclude that maintenance, as well as repair of a torsion bar suspension, is associated with such situations:
- Structure height adjustment.
- Dismantling or replacement of torsion bars.
- Replacing needle bearings.
- Replacement of pins, axles of the rear beam.
- Repair of rear beam levers.
Adjusting the height of the rear suspension should not be considered as a repair of the entire structure. This usually happens due to the fact that the owner of the car wants to raise back auto.
Sometimes a change in the height of the beam is provided in order to increase rigidity and reduce the draft of the car rear, while maximum load. You need to know that the rear beam torsion bar is not able to work when the height of the rear beam changes, it will be operated under a more aggressive load, and this may affect its resource.
The process of changing the height consists in changing the position of the torsion bar, or rather its splined end, as well as the sprocket. The torsion bar has slotted connectors at the ends. The torsion bar is attached at one end to the slotted connector, the rear beam lever.
And others - in the slot on the beam body. If repairs are being made of this type suspension, then you need to dismantle the torsion bars.
In this situation, it is important to make the native position of the torsion bars in the rear beam, so that at the time of installation it is clear what and where it is inserted. In order to dismantle the torsion bar in the process of tightening from the spline connection, an inertial puller is used.
The puller pin is screwed into the thread on the end of the torsion bar, maybe this thread should be cleaned.
Often, spline connections “sour” or “stick”, in this case, a standard puller will not help, only an ordinary sledgehammer can help out.
Often torsion bar suspension repair is associated with the process of replacing the needle bearings of the rear beam. According to some data, the process of replacing needle bearings is needed after 80,000 km of run.
When replacing bearings, it will be necessary to dismantle the torsion bars, as well as the beam levers. Each side of the beam contains two bearings. The most dangerous problem of the rear beam is the wear of the needle bearing, because it is difficult for an ordinary motorist to determine this.
In the absence of diagnostics, the car is also operated with a crumbled bearing, thereby exacerbating the problem. As a result, the axle wears out. Of course, it is possible to replace the axles of the rear beam, but this is very difficult in "home" conditions, since in addition to knowledge and experience, special equipment and fixtures.
Stations Maintenance will not replace the axles, but only offer a new beam assembly with new axles, and this is a very expensive proposition.
The most severe case in the repair of a torsion-type structure is the destruction seat bearing in the lever. This happens rarely, in a very "neglected" situation.
The destruction of the seat occurs for the reasons that the pin of the rear beam, although much less often, since this place is protected by the outer race of the bearing. Lever repair process: restoring a seat on metal-cutting equipment.
The main problem of restoring the beam arm is finding the required equipment, such work is carried out on a boring and turning machine.
Gallery
In this section, there are photos of torsion bar suspensions for a tank, trailer and others.
If you are going to buy a car, you should find out the pros and cons of a torsion bar suspension in order to decide whether to choose a car with this type, or turn your attention to more traditional equipment. The installation of a torsion beam among the French is especially popular - almost all Renault models, Peugeot and Citroen are equipped with it.
Often this mechanism is even called a French beam, although it is based on an idea first embodied in a car. Volkswagen Beetle(and this happened in the 30s of the last century), and the Czech Ledvinka and the German Ferdinand Porsche improved the detail. The main part in the suspension is the torsion bar. It is an elastic segment made of metal, designed to work on twisting.
Most often, a torsion bar is a round rod part with spline connections at the end, however, it can be made from a beam or a collection of special plates. On one side, the mechanism is attached to the car body or car frame, and on the other, to the lever. In motion, the torsion bar twists, which tightly binds the wheels to the body. The torsion beam can be oriented along the axis of the vehicle (this option is used in heavy trucks), and maybe a transverse one - this is exactly what is mounted on cars, and mostly rear-wheel drive ones.
The pros and cons of the torsion bar suspension are due precisely to the peculiarities of its structure. Let's take a closer look at the advantages and disadvantages of such a mechanical design, which has already become quite familiar and used in many cars.
What do we have on the plus side?
The main gain is in the compactness of this type of assembly. Due to the small dimension, it becomes possible to build quite big trunk and provide enough space to accommodate rear passengers- that is, space is added. A very valuable quality is also the dependence of the stiffness of the suspension on the size of the torsion bar: the longer it is,. In addition, the adjustment for hardness / softness is very simple and feasible even on your own at home, so to speak, conditions.
There is even the possibility of some clearance adjustment. The redistribution of the dynamic load from the track over the entire frame of the car increases its stability and makes the car more obedient to drive and operate. In maintenance and repair, a torsion bar suspension is (in most cases) simpler and cheaper than a spring one. Its total weight is again much less than that of the traditional one, which has a good effect on the economy of the ride and the service life of the entire car (a resource is added). In the opinion of the manufacturer, the advantage of the torsion bar suspension is in its not too expensive manufacture and practical ease of installation.
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What went down?
However, no device, as a rule, can be perfect and ideal. Even the most successful engineering ideas have some unpleasant sides. In the torsion bar suspension, experts found the following, not entirely pleasant shortcomings:
- The most basic and noted minus is shaking on back seat. Additional vibrations go to the body, which are felt very well by all passengers behind;
- High-quality sound insulation cannot be achieved even with additional measures - all for the same reason that people behind are not too comfortable;
- You will have to drive more carefully and carefully: the presence welds and, accordingly, the presence of voltage in them limit the maximum permissible load for suspension;
- Torsion bars tend to burst like springs. But they still cost much more significantly;
- The low cost of repairs with maintenance can also become very relative. It already depends on design features each model. If for repair work it will be necessary to dismantle the entire beam when replacing the torsion bar (and enough models are designed in this way), then the bill for the services will be quite substantial. If you are given the opportunity to get close to the replacement part without global dismantling, then yes, the price will be lower than for similar work with a spring suspension.
