Laser photoelectric ensures automotive manufacturer gets the right gear

The automotive industry is perhaps the largest employer of automation, using it to provide efficiency and to ensure the accuracy that is an essential part of vehicle reliability. An automotive first-tier manufacturer of forged and machined components trusts Contrinex distance-measuring photoelectric sensors to ensure that the correct gear is fitted in an assembly.

The manufacture of a gear assembly allows a choice of two gears to be fitted into the same location within the assembly dependent upon the version being assembled. A reliable and auditable method of ensuring that the assembly contains the correct gear for the version being produced was required.

Analysis of the parts highlighted that the height of the assembly differs depending on which gear has been fitted and this feature is therefore used to identify which gear is present. A distance measurement sensor is used, but because space is limited, a compact sensor with a long sensing range was required.

Contrinex’s DTL-C23PB diffuse laser distance measurement sensor offers an operating range of 20 to 100mm in a small 30 x 20 x 12mm sensor. Its compact size and IP67/IP69K-rated housing made it suitable for this industrial environment.

Whilst the DTR-C23PB’s sister sensors offer a longer 200mm sensing range, the DTL-C23PB was selected because it uses a laser light source which provides a small beam spot, only 1.5mm in diameter. This is ideal for accurately measuring the curved surface at the top of the gearbox assembly.

For one version of the assembly, when the gear is in place the sensor’s beam is deflected, whereas for the other, its greater height obstructs the sensor beam and triggers the sensor output. The sensor is part of a Poka-Yoke system which stops the production process if the incorrect gear assembly is presented to the gearbox, thus correct assembly is ensured for the manufacturer and in turn for their customer.