Audi 80/Avant (B4)

since 1991-1995 of release

Repair and car operation

Audi 80/Avant
- Technical specification
   15-inch wheels
   Brake system
   Passive safety
   Full drive
   Distributive Torsen-differential
   Dynamics of movement at a dry paving
   Instructions on operation for all-wheel drive cars
   Blocking of differential of the back bridge
   Motor compartment
   Regular servicing
   Workplace organization
   Lubricant works
   Consumption of oil
   Right choice of engine oil
   Replacement of engine oil and oil filter
   Check of level of working liquid of the amplifier of a wheel
   Check of level of oil of a mechanical transmission
   Check of level of oil in a drive of the back bridge
   Control of level of ATF in an automatic transmission
   Check of level of oil in the main transfer of an automatic transmission
   ATF replacement
   Greasing of hummock drives, hinges and locks
+ Engines
+ System of production of the fulfilled gases
+ cooling System
+ Fuel tank and fuel pump
+ Air filter and airintaking channels
+ injection System
+ Coupling
+ Transmission and transmission
+ Suspension bracket and steering
+ Brake system
+ Anti-blocking system of brakes
+ Wheels and tires
+ Body electrosystem
+ ignition System
+ Lighting
+ Signalling devices
+ Devices and auxiliary devices
+ Heating and ventilation
+ body Elements
+ Search of malfunctions
+ Specifications

Full drive

On an illustration the distributive Torsen-differential in a cut is presented.

1–a leading gear wheel (a drive to the forward bridge);
2–a hollow shaft (a drive from the transfer mechanism);
3–differential case;
4–the flange/driveshaft (for a drive of the back bridge);
5–worm of the main transfer of the back bridge;

6–cylindrical gear wheels;
7–axis of worm wheels;
8–worm wheels;
9–worm of the main transfer of the forward bridge.

If will establish authorship of any firm in a question of introduction of a full drive for serial cars «in decent society», it, undoubtedly, will give Audi.

The identikit of the Audi 80 quattro car demonstrates transmission to the back bridge with the driveshaft, the main transfer of the back bridge and leading semi-axes of the back bridge.

The VW Iltis SUV developed by request of the Bundeswehr by Audi firm for Volkswagen, most likely, served as a germinal cage for idea of quattro (a full drive). The legend says:

during a winter trip in Northern Sweden one modest «Iltis» far overtook much more powerful and fast front-wheel Audis. After that the head of tests of a running gear of that time wished to have «the all-wheel drive car with sufficient capacity» as the daily car. And as it is known that there is nothing stronger than the idea which time came (and this idea, appear, was such), over the concept worked until legendary Audi quattro was presented.

Concepts of a full drive

Connected full drive

Until recently the concept of «the all-wheel drive car» was almost inseparably linked with concept of «the off-road car». The concept of a full drive of the last was quite simple: to a standard drive (the engine ahead, the drive back) was simply attached one more drive, namely to the forward bridge one more transmission through a transfer case and the additional driveshaft conducted.

Trips were carried out usually with a standard drive and only if it was demanded by situation on the road, the forward drive was connected. This design with a connected full drive and is today usual for cars of the increased passableness (SUVs).

Lack of similar system: at trips on a firm covering the full drive should be disconnected, because on turns forward wheels pass longer way, than back. Various frequency of rotation of wheels result in difficulties with management.

Constant full drive

So, if the idea came to the head to create the constant full drive which is constantly operating on all four wheels, it is necessary to create the device preventing a proskalzyvaniye of wheels. This problem is solved by so-called interaxal differential.

Differentials in automotive industry are known for a long time. They distribute a torque between right and left driving wheels.

There too it is necessary to counterbalance forces because, as we know, the external wheel passes on turns longer piece of a way, than internal. The role of the balance weight assumes axial differential. He allows to transfer the moment to both driving wheels depending on angular speed of each of them.

The design of Torsen-differential is based on a principle of a worm gear. The worm gear can be calculated in such a manner that it will possess big or smaller factor of blocking.

1–a worm, 2 – a worm wheel.

In the winter, for example, happens so: the wheel standing on ice is turned, and the opposite wheel on a rough covering does not transfer any force and consequently costs. One is clear: the similar differential is not necessary for a role interaxal because it is necessary to achieve opposite effect. Force should be transferred there where wheels can move the car. Namely there, where the paving possesses good coupling. And as the driver never it foreknows, distribution should occur automatically.

After various development stages, including interaxal differential blocked manually, the all-wheel drive Audi quattro models today are completed with so-called Torsen-differentsialom.