Measurement Hairpin

In the field of e-mobility, the hairpin process has become established in the development of e-motors and the associated production. Here, copper wires, similar to a hairpin, are inserted into the grooves of the stator and welded. In the production of the individual hairpins, the copper wire passes through the following production steps: Stripping, cutting, bending and welding. Dimensional accuracy is a basic requirement for the subsequent fully automatic assembly steps, which guarantees a smooth production process.

With the help of four line scan cameras a 360-degree control of the stripping process of the copper wire is carried out. For this purpose, the wire is transported centrally through the LED illumination unit and the cameras. There must be no residues of the insulation coating on the surface of the wire. In the subsequent bending process, the hairpin is measured for its dimensional accuracy using area cameras and telecentric lens in a transmitted light process. The length, parallelism and angle of the hairpins are checked. In a further test step, the torsion of both hairpin ends is measured with an area scan camera.

The customer is provided with the individual measured values and parameters via the visualization of the system. The measured values are also transferred to the machine control system and thus flow directly into the production processes. If the limit value is exceeded, the corresponding hairpin is rejected. The measured values that lie within the tolerance are also available to the machine control system as control variables. Thus, the NOK portion of hairpins can be minimized and the process can be optimally designed. The effectiveness of the machine is significantly increased by this control process.