Shaft-hub connection

A shaft-hub connection with a key

In mechanical engineering, shaft-hub connections are mostly standardized types of connection in order to transfer torque and power from a shaft or journal to a rotating hub (or vice versa from a hub to a shaft). However, they also transmit axial forces, transverse forces and bending moments that arise on hub gears, for example on gear wheels (for example through helical gears ) or on pulleys or the like.

Subdivision of shaft-hub connections

Breakdown by type of power transmission

Depending on the type of power transmission , shaft-hub connections can be divided into:

1. Non-positive connections (frictional connection): The power transmission between the shaft and the hub takes place through frictional resistance, which occurs through press fits , or through special clamping elements such as clamping hubs or shrink disks , both with conical elements;
2. Positive connections in which a certain shape, eg. B. splined shaft profile , polygonal profile , splined shaft profile and serration or additional driver elements ( feather key ) the power transmission is achieved. A distinction is also made here between indirect and direct form fit;
3. Pre-tensioned form-fitting connections: This combination of the two types of connection mentioned above arises u. a. when using wedges ;
4. Cohesive connections, e.g. B. by gluing , soldering or welding .

Breakdown according to stress and movement requirements

In addition, it is also possible to differentiate between stress and movement requirements:

1. Small torque: Terminal connection adapter sleeve , cross pin , spring washer ;
2. Large and reciprocal torques: interference fit and oil interference fit ( interference fit ), ring spring clamping element such as B. clamping set or taper bush ,

Form-fitting shaft-hub connections

Form-fitting shaft-hub connections (WNV) can also be divided into:

• direct torque transmission (torque is transmitted directly, e.g. spline shafts, press-fit assemblies),
• indirect torque transmission (torque is transmitted via intermediate links, e.g. feather keys).

Form-fit WNV are subject to surface pressure on the circumference, which can be calculated as follows: ${\displaystyle p\leq p_{\text{zul}}}$

${\displaystyle p={\frac {T\cdot K_{A}\cdot K_{e\beta }\cdot K_{1}}{z\cdot h_{w}\cdot r_{w}\cdot l}}}$

With

${\displaystyle T\colon }$ Nominal torque

${\displaystyle K_{A}\colon }$ Application factor / shock factor

${\displaystyle K_{e\beta }\colon }$ uneven load distribution on the teeth

${\displaystyle K_{1}\colon }$ uneven load distribution over the length

${\displaystyle z\colon }$ Number of drivers

${\displaystyle h_{w}\colon }$ load-bearing height of the driver

${\displaystyle l\colon }$ load-bearing length

${\displaystyle p_{\text{zul}}\colon }$ Strength of the weakest material

${\displaystyle r_{w}\colon }$ Profile center radius for spline and serrated shafts

Individual evidence

1. ↑ ^{a b} G. Niemann, H. Winter, B.-R. Höhn: Machine elements Volume 1: Construction and calculation of connections, bearings, shafts , 3rd edition, Springer