Measure the pinions of a truck

[AX3L]

Hi guys!
I've been given the project to automate the process of measuring the pinions and do it by the line rather than in a separate room. That is, measuring all the diameters, some lengths and the cogs themselves. The cogs are the difficult part where every cog is turned and convex. Today were measuring everything manually, and the cogs with a machine using a probe. One idea for the lengths and diameters is to use laser, another is to use some kind of sensors like capacitive or maybe inductive for the diameters. I know laser with a "wide beam" is often used to measure cogs so that's one (if not the only except probes) alternative but on the other parts it's hard to see which one is better and more reliable. Any inputs and/or thoughts is therefore deeply appreciated!

Sincerely
Axel

 

[MikeHalloran]

The technology that's most appropriate for measuring your pinion production depends strongly on the tolerances to be achieved and the production numbers.
... neither of which is so far in evidence here.

When I worked in an axle plant, 45+ years ago, bearing and seal diameters were measured with air snap gages right at the grinders, most other diameters were measured with mechanical indicator snap gages, and most lengths were measured with step gages. I think the hypoid teeth were checked by running them against master parts.




Mike Halloran
Pembroke Pines, FL, USA

 

[CoryPad]

There are good reasons to measure off line in a room with controlled environment. If you are not concerned with those reasons, laser devices (such as those from Keyence) could be suitable. A proper gear inspection device is required for hypoid teeth and does not seem like a good fit for a manufacturing environment is there are no controls for environment.

 

[AX3L]

Mike: For the tolerances, the lower the error the better of course. Ideal would be 1 micro meter, I assume that's not possible but it have to be at least in that area.
The mechanical measurement you're talking about is about the same we use now and it works when we measure only every 10 piece or so. Master parts would work great and is something we use on a regular basis, it's not possible here tough I think since we have at least 50 different cogs and therefore would need 50 master pieces.
It's always nice to hear about some proven methods though!

Cory: Laser is a great option and something we're looking at right now! Of course a specific, controlled room for the measuring would be ideal but we think we'd benefit more from measuring every single piece instantly to be able to detect problems before we run the next piece rather than measure every 10 or 20 piece with super accuracy. Do you have any idea what such a laser equipment would cost per unit, approximately?

 

[CoryPad]

$1 000 to $100 000

 

[tbuelna]

There are multi-axis CNC grinders that can perform all of the finish grind operations (bearing journals, gear flanks, etc.) in a single machine using a single set-up. Some machines also have integral CMM probes that periodically check the accuracy of the ground surfaces and can automatically compensate for tiny variations due to grinding wheel wear. Performing all of the finish grind operations in a single set-up eliminates a potential source of tolerance errors.

It is usually best to inspect the accuracy of ground gear flanks and journals while the part is still on the machine, when something can still be done to correct the problem. Of course, doing so also probably means increased cycle times.