Vision system reduces false rejects in wheel nut manufacture

Share this on social media:

Maclean Vehicle Systems (MVS), a company manufacturing automotive fastener products, among other components, is using machine vision to verify wheel nuts are properly threaded.

The nuts are assembled on an index machine that processes two parts simultaneously at each station. MVS previously performed the fastener inspection with an eddy current sensor, the accuracy for which was not high enough and at times resulted in expensive over-sort.

MVS mounted two Cognex Checker 101 vision sensors looking down at a 45 degree angle about five inches from the two parts in the inspection station of the assembly machine. The parts are presented to the inspection station in a fixture and held in position by a spring-loaded keeper, so there is some variability in the height at which they are positioned.

The variable placement of the part was addressed by using an edge finder tool to locate the edge of the part. Then a brightness tool was used to look for the light reflecting off the threads.

'We looked at a number of different vision sensors,' said TJ Konieczke, manufacturing controls engineer for MVS. 'We selected Cognex Checker vision sensors because they are very easy to program and operate. We simply put them in place, connect a PC to the USB port, train them on the part to be inspected, and pick tools off a menu that inspect the critical features of the part.'

The ability of the vision sensor to determine the position of the part and evaluate the brightness of the entire opening of the nut as opposed to an individual point evaluated by a traditional sensor has eliminated incorrect pass/fail decisions. The elimination of sorting costs quickly paid for the new vision sensor. The vision sensor has also increased confidence that not a single bad part will be shipped to the customer.

Recent News

12 February 2021

Video recorded at 2,800 frames per second has been used to test high-speed trains travelling through the newly opened Ceneri Base Tunnel in Switzerland

29 July 2020

The Perseverance rover contains 19 cameras, including seven scientific instruments. It will analyse the climate and geology of Mars, looking for signs of past life, as well as monitoring the Martian atmosphere

02 July 2020

Norwegian seafood firm, Lerøy, has installed hyperspectral cameras on processing lines to sort fish. The system is able to measure the amount of blood in white fish, which gives a grade of quality

09 June 2020

Hyperspectral imaging is being used in a research programme at hospitals in Maryland and New York to investigate the prognostic value of skin findings associated with Covid-19 infection