Bestech ’s range of optical micrometers, from Micro-Epsilon, are being used during engine production at Volvo in Sweden. These micrometers are essentially a laser line with a receiver on the other side of the object to measure the shadow from the laser line. However such a method is found to be extremely accurate and reliable, with a 0.2%FS accuracy for measuring ranges of 75mm or 100mm.
The sensors of the optoCONTROL 1202 series can be used to measure the diameter of bearing caps and therefore automatically verify whether a bearing shell is present in the cap or not before being mounted by a robot.
The bearing caps are transported on a workpiece carrier directly under the laser light band of the sensor. A robot picks up the bearing cap and lifts it so that the light band measures approximately 3mm to the bottom edge of the bearing cap. The transmitter and receiver of the optoCONTROL are then mounted with a distance of 1,300mm between them. The optoCONTROL 1202-100, with a light bandwidth of 100mm is used. The emitted light band is partially covered by the bearing cap, and the size of the part is measured based on the shadowed light band.
The robot lifts the bearing caps into the light band one after the other, with up to six bearing caps on a workpiece carrier. The measurement object can be freely positioned in the light band due to the large distance between sensor and receiver. The bearing shells have a thickness of approx. 1.5mm. This means the measured diameter is 3mm too large if no bearing shell is present and the bearing cap is then rejected. If the bearing cap is recognised as OK, the robot transports it for further mounting.