An axle to a machine element, which serves for supporting and storing of the rotatable parts. This can be, for example wheels, rollers, or warehouse. Colloquially, the terms shaft axis and are often confused with each other. Thus, concepts such as semi-axis in vehicles naturalized, even though it technically is a wave.


A distinction is made between fixed and rotating ( co-rotating ) axes. In contrast to the axle shaft has a plain bearing or bearing function but does not transmit any torque. It is therefore only loaded with bending moments and / or axial forces.

Fixed axis

On fixed axles loose rotating components are assembled (eg pulleys ). They are subjected to mechanical stress by resting or swelling bend.

Rotating axis

Are the non-driven wheels, rollers, etc. firmly connected to the axis, the axis is referred to as the circumferential axis. By the rotation of the static forces in the axis to a changing load ( bending) are. The Fluctuating requires larger axle diameter than with fixed axes, but usually no longer required an elaborate storage and time-consuming installation of the same.

Solid and hollow axles

Since the material is less compressed or stretched inside of axes for bending load (radial) on the outside, it contributes less to the stability; Therefore, there is the hollow axis, which, based on its mass, a higher stability than solid shafts, and in particular of bicycles are known (in combination with quick release ).

Journals or stub axle

On an axis offset with reduced or axle ends, are mounted on the rotating components, the remote ends of spindles may be mentioned. The paragraph can be used for lateral fixation of the axis. On the axle roller or journal bearings are fixed, which are then passed themselves each in a bearing block, or the journals themselves form the inner race of a bearing ( eg typical bicycle axes).

  • Machine element