Gripples orientated thanks to Cognex Checker camera

Aylesbury Automation has helped Gripple Ltd to solve a complex problem in the assembly of its new Gripple design by providing a smart sensing Cognex Checker to help orientate small parts being fed into an assembly machine.

Gripple Ltd is an award-winning company that has given its name to Gripples, the wire-joining and tensioning devices with industrial, agricultural and horticultural uses. Gripples are assembled at the company's manufacturing base at the Lower Don Valley in Sheffield.

John Joyce, Technical Director of Gripple Ltd, states: "We required a solution that did not interrupt the manufacturing and assembly process and that would have the sensitivity to recognise product parts in order to achieve the best machine cycle times."

Future-proof sensing

The solution had to ensure that small gripple parts are fed at the correct orientation from a step feeder. There were several difficulties that needed to be overcome in order for the gripple parts to be presented in one of four acceptable orientations. Aylesbury Automation specified a Cognex Checker that not only solves the problems, but allows flexibility in the assembly process if changes are made in the future to the design of gripples. Changes in design will now have no effect on the tooling of the feeding system, which operates at a rate of 30 parts per minute.

Gripple parts exit the Schindler step feeder onto a linear vibrating track that carries them to the machine. Parts that are orientated incorrectly are recycled back into the step feeder by an air jet that blows parts off the linear track. To add to the problem of detecting incorrectly orientated parts, the gripples are on a vibrating linear track that precludes the use of ordinary sensors.

The Cognex Checker, a single unit vision multi-sensor with built-in lighting and optics, recognises images of the gripple parts and simultaneously detects several of the products' features while taking into account that there may be changes in orientation due to the vibrating track. A solenoid valve is directly powered by the output signal from the Checker. The system provided by Aylesbury Automation ensures continuity of the assembly process without the need to stop the gripple part and test its orientation and, if necessary, reject it.

John Joyce says: "The addition of the Checker to our production line has solved a complex problem. We will now be considering fitting the system to our existing lines. There usually are solutions to most assembly problems but it is finding the right one that is time-consuming. Aylesbury Automation had the experience we required and, furthermore, has delivered a solution that is also future-proof and that will, in time, bring us even greater benefits."