Axles are needed for the vehicle to move. Since axles are an important part of the vehicle that ensures cornering safety, I will briefly explain how they work. Whether it is front-wheel drive vehicles, rear-wheel drive vehicles or other 4-wheel drive transmission types, they all have similar working patterns, although their axle features may vary. It is the mechanism that allows the wheels of a vehicle to rotate and transmits the power of the engine to the wheels.
Axle How it works :
In front-wheel drive vehicles, since the engine sits sideways on the body, the transmission is shifted to the right or left. While the axle shaft on the passenger side is generally longer than the driver’s side, in rear-wheel drive vehicle models, the axle lengths are the same because the differential is in the middle of the vehicle. The axle is a piece made of extremely strong impact-resistant steel that transfers the rotational motion received from the transmission in front-wheel drive vehicles or the movement received from the differential in rear-wheel drive vehicles to the wheels. While doing this, it assumes the entire load on the vehicle. It is responsible for ensuring safety and comfort in the transfer of engine torque or engine braking during vehicle acceleration or deceleration and in corners during turns.
Why is the axle important :
Since it is connected to the wheels, it adapts to every movement the wheel makes. When the wheel falls into a pothole, it bends down, when it hits a bump, it moves up, and when the tires turn right or left, the axle length continues to lengthen and shorten, giving movement to the wheel. The wheel spins as fast as it spins. However, this rotation is the rotation of the shaft. Since the tripod bearings inside the axle and the sleeve rotate at the same time, the axle bearings do not rotate within their own sleeves. If such a rotation occurs, the axle will be broken. The axle only makes angle movements and extension and contraction movements within itself. Thanks to its joints, it follows the shock absorber and wheel movements with great synchronization. Since the axle is a constantly rotating and very moving part under the vehicle, something can happen to it at any time. You can think of it just like a person’s arm or leg. It can provide all kinds of movements thanks to the 2 joints on it. These joints are the weakest points of the axle and where fractures occur. The axle basically consists of 3 parts: inner axle, outer axle and axle shaft. In front-wheel drive vehicles, there are two axles on the left and right side of the transmission.
In front-wheel drive vehicles, the transmission and the differential are in a single box, that is, the inner sides of the axles are directly connected to the transmission. The milled part on the axle shaft at the end of the axle sleeve, or axle tulip, fits into the transmission. There is a seal at the junction of the axle shaft and the transmission that prevents the transmission oil from flowing out. Although it varies depending on the axle model and type, the most commonly used type in vehicles is this type of axle with constant velocity joint and tripod bearing. Thanks to the triple bearing mechanism inside the axle housing, it moves back and forth in this housing. In this way, the axle length becomes longer or shorter depending on the position of the wheel. There are also different axle shapes that allow the axle length to be lengthened or shortened. Axle bellows are located in the inner and outer parts of the axle. Bellows are thick rubber parts filled with grease that protect the joints of the axle, and since they are the weakest point of the axle, they are the part that is most damaged. The axle shaft connects the inner axle and outer axle to each other and is made of high hardness steel. There is a Rzeppa joint bearing structure on the outer axle. The milled part at the end of the axle is directly attached to the wheel hub and rotates in the directions in which the wheel rotates. This part of the axle is also called the axle head. Yes, friends, I tried to explain the general structure, functioning and importance of the axle, I hope it was useful for you. In our next video, I will discuss what happens if the axle breaks.