Gear Axle

Gear Axle is just a central shaft that is required for rotating wheel.Sometimes, the axle can be made fix in its position by placing a bearing or brushing inside the holes of the respective wheels or gears. This is done in order to rotate the wheels or gears around the axle. In other cases, the wheel or gear is made fix to the axle by placing bearings or bushings at the mounting point from where the axle gets support. In bicycle, such kind of axle-arrangement (latter one) is called as a spindle.

Vehicle Axles
Axle is a very important physical component of vehicle having wheels. An axle helps the wheels in maintaining their relative position and also the vehicle body in maintaining its position. The axle performs a vital role in vehicles. It bears the entire weight of the vehicle's body, the cargo which is loaded on the vehicle and the acceleration force between the vehicle and the ground. According to the structural design of the vehicle, an axle may serve the following functions:

Drive Axles
For a drive train, one or more axles may be its constituent. In automobiles, the engine sends the rotational force on the axle and the axle transmits that force to the wheels. These wheels then accelerate the entire body of the vehicle.

Braking Axles
Force has to be applied on the axle in order to stop the rotation of the axle. In consumer vehicles, the brake-force is exerted over the wheel-system but in the engine-braking system, the force is exerted upon the axle directly.

Steering Axles
The common example of steering axle is the front axle of the automobile. The movement of the vehicle is regulated by checking the direction of the rolling axle of the wheels. The checking is done according to the body and rear wheels of the vehicle.

Structural Features of Various Gear Axles
Gear straight axle is a firmly fixed hard long rod which joins a left sided wheel to a right sided wheel. The rotational axis that is formed by the axle is common for both the wheels. This type of structural configuration assists the wheels to remain in their positions and also to afford the heavy load of the vehicle. In trains, the straight axles are used while the rear axles are used for heavy-loaded trucks and for other heavy duty off-road vehicles. By closing the length of the axle in all sides in a housing, it can be protected and strengthened. The wheel on each side, within a split design is aligned to a separate shaft. In modern cars, generally, the split front and rear axle are used, because from such kind of arrangement, independent suspension can be obtained from the left and right wheels, which gives a smoother journey. This arrangement also allows the left and right wheels to rotate at different speeds as the vehicle turns. This helps in improving the adhesive friction of the tyres on the ground and it extends the life of the tyres.

When two or more than two gear axles form a close group, a tandem axle is formed. This kind of group arrangement is formed to provide additional weight capacity rather a single gear axle.

Types of Gear Axles
The gear axles may be divided into different types. But, from vehicle-utility purpose, two important types of axles are:

Drive Axles
A drive axle is an axle that is driven by the engine. Actually, the split axle with differential and universal joints between two half axles, is known as Drive axles. The connection of each of the half joint is done with the help of constant velocity joint. The constant velocity joint helps the wheel assembly to rotate freely vertically and in resting and turning in a bearing when making turn. The engines of cars and trucks having rear wheel drives, turn drive-shafts. This turning of a drive-shaft, passes on the rotational force to the drive axle at the rear of the vehicle. Although, the drive axles are considered as very useful, but today's car manufacturers, prefer the use of split axles with differential forms. A single drive axle may be used in some simple vehicle designs.

Dead Axles
Dead axles are not parts of drive trains, they are free-rotating. The example of a drive axle is the rear axle of the front-wheel drive car. Merely for load-carrying purposes, many trucks and carriages use dead axles. A dead axle may be called as a pusher axle, when it is placed just in front of the drive axle. When a dead axle is placed just behind of a drive axle, it is called as a tag axle.