Poka Yoke Inspection Retaining Ring (C-Clip)


I want to find a poka yoke solution for checking if a C-Clip is properly sitting in its groove. The C-Clip is currently being checked by a gauge pin which has a 2.5 mm diameter. Is there any possibility to check this in another way which is 100% safe. The gap opening (inner diameter) from the C-Clip must be less than 2.5 mm, otherwise the C-Clip doesn't sits properly in its original shape. The tolerances are +-0.05 mm

Would be grateful for some ideas. Thanks.
Assuming you want an automated system, a vision system can work. Can the part be oriented consistently for a camera?
Actually yes, but a vision system would be too expensive for this issue. Is there an option to use digital caliper which is connected to a PLC and gives feedback/ interlock with machine to prevent from continuing? tested already, CT would not even increase that much. Maybe by using RS232 cable, anybody experience with caliper connections?

Proud Liberal

Quite Involved in Discussions
You may want to investigate use of a ball gage to detect the opening. The benefit of a ball gage vs a pin gage is that orientation is less of an issue when evaluating a slot opening (two parallel planes) using a sphere (2 point contact). A pin gage (when aligned with the slot) would be 2 lines of contact.

I've setup one into a spring loaded mount that is setup with a proximity switch to detect whether the gage will pass through the opening being evaluated.

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A Sea of Statistics
Superdry123, a few words of caution re: (AOI) automatic optical inspection, a great time error reducing method however, one must ensure that the object code or AOI software program havs been properly validated and where necessary hack proofed....second at the beginning and end of each shift a "red rabbit" (known bad part) and Golden rabbit (known good part) must be used to verify proper operation...these known quantities must be kept under lock and key with access only to shift supervisor or similar person.

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