Many will agree that the engine is the foundation of the car. And indeed it is. However, imagining a car without steering is also difficult. This is an important and necessary element in every machine. The task of the steering is to ensure the movement of the vehicle in a given direction. This node consists of several components. This is the steering wheel, column, drive and steering gear. We’ll talk about the latter today.
Functions
The steering mechanism has several main tasks:
- Transfer of effort to the drive.
- The increase in effort that is applied by the driver to the steering wheel.
- Independent return of the steering wheel to the neutral position when unloading.
Varieties
This element can be of several types. Today, the following types of steering mechanisms are found:
- Rack and pinion.
- Worm.
- Screw.
What is each of them? We will consider all these types of mechanisms separately.
Rack and pinion
At the moment, it is one of the most common. It is mainly installed on cars and crossovers. The rack and pinion steering device assumes the following parts:
The first was mounted on the steering shaft. The gear is in constant engagement with the gear rack. This mechanism operates quite simply. When the steering wheel rotates, the rail moves to the right or left. In this case, the traction that is attached to the drive, turn the steered wheels at a given angle.
Among the advantages of this mechanism, it is worth noting the simplicity of design, high efficiency and high rigidity. However, this mechanism is very sensitive to bumps on the road, which is why it wears out quickly. Often, owners of used cars are faced with the problem of knocking rails. This is a consequence of the wear of the steering gear. Therefore, the element is installed only on certain types of vehicles. These are mainly front-wheel drive cars with independent front suspension. If we talk about the VAZ, then the rail is found on all models, starting with the "eight". On the "classic" is set a slightly different steering mechanism.
Worm
This type is used on domestic "Lada", as well as on some buses and light trucks. This node consists of:
- Globoid worm of variable diameter.
- The steering shaft with which the worm connects.
- Roller.
Outside the steering gear is a bipod. This is a special lever that is connected with the drive rods. The steering mechanism on the GAZ-3302 is arranged in the same way.
Among the advantages of such a node, it is worth noting less sensitivity to shock loads. Therefore, this steering gear, installed on the VAZ-2107, is almost eternal. Owners rarely encounter knocking and vibration on the steering wheel. However, this design scheme has more connections. Therefore, periodically, the mechanism needs adjustment.
Screw
This is a more complex node in the device. Its design includes:
- Screw. Located on the steering wheel shaft.
- Nut. She moves through the previous item.
- Rack.
- Gear selector. It is connected to a rail.
- Steering bipod. Located on the selector shaft.
A key feature of this mechanism is the method of connecting the nut and screw. Mounting is carried out using balls. Thus, less wear and friction of the pair is achieved.
The principle of operation of a screw element is similar to a worm element. The steering wheel is rotated by rotating the screw, which moves the nut. The latter moves with the help of a rack the gear sector, and with it the steering bipod.
Where is the screw mechanism used? Often, it is used on heavy commercial vehicles - trucks and buses. If we talk about cars, then this is only a representative class model. The mechanism is more complicated in the device and expensive, therefore, it significantly increases the cost of the car itself.
Amplifier
Now almost all cars use power steering. It serves to reduce the effort required to turn the front wheels. This element allows to provide high accuracy and speed of steering. At the moment, there are several types of amplifiers:
The first type is more popular. It is installed both on cars and on trucks. The amplifier device has a pump that creates a certain pressure in the hydraulic system. Depending on the steering side of the steering wheel, this fluid presses on the first or second rail circuit. Thus, the force that is required to rotate is reduced. Among the advantages of the hydraulic system, it is worth noting high reliability. The amplifier rarely fails. However, since the pump mechanism is driven from the crankshaft, part of the power is taken from the engine. Although on modern engines this is completely invisible.
The electric amplifier consists of a separate motor. Torque is transmitted from it to the steering wheel shaft itself. The design is used only on cars, as it is not designed for great effort.
The EUR is equipped with separate electronics, which controls this engine. Sometimes the amplifier is understaffed with adaptive systems that are aimed at increasing safety when driving in a lane.
Among the innovative solutions, it is worth noting the dynamic control system from Audi. Here the gear ratio varies depending on the current speed of the car. Thus, at high speeds, the steering wheel is hard and knocked down, and when parking it becomes easy. The gear ratio is changed using a twin planetary gear that is added to the shaft. Its body can be rotated depending on the speed of the car.
Conclusion
So, we found out what this mechanism is. This is a very responsible node in the steering. Regardless of the type, it must be checked periodically. After all, loss of control at speed is the most dangerous thing that can happen to a driver.