Hi,

We are in business of making auto electrical parts. We need to test 1000 + starter motors in a shift in the test rig. Checking the speed of the motor is one of the important parameter. While testing, we are not allowed to engage the motor drive shaft (pinion) with anything (free run). We find it difficult to reliably check the speed with "magnetic pick-up", considering the size of pinion teeth. Also, change in the diameter of pinion for different models requires adjustment of the "magnetic pick-up". Can this community suggest alternate method / sensors?

I do not have part numbers or anything, but I know that there are some highly sensitive optical sensors out there as well as some decent laser tachs that could easily be integrated into a system such as this.

Take a look at keyence sensors they have optical sensors that will pick up extremely small variations, plus most have a simple one touch set up, so this should satisfy your requirements when it comes to changing model types. Give one of there technical reps a call and they will be happy to help

Regards

Tagg

What about a standard tachometer with friction wheel (with conical hole) pressed axially against end of shaft/gear? The whole setup could be on a spring-loaded slider mechanism to accomodate different shaft/gear diameters and lengths.

Walt

quote:

Originally posted by Tag:
Take a look at keyence sensors they have optical sensors that will pick up extremely small variations, plus most have a simple one touch set up, so this should satisfy your requirements when it comes to changing model types. Give one of there technical reps a call and they will be happy to help

Regards

Tagg

Thanks Tagg. But we did contact Keyence in first place and tried a few Keyence sensors including a laser fine spot. We could not reliably sense the speed. Is there a hall effect sensor which can detect the minute make and breake of current in the commutator?

Thanks.

quote:

Originally posted by Walt Strong:
What about a standard tachometer with friction wheel (with conical hole) pressed axially against end of shaft/gear? The whole setup could be on a spring-loaded slider mechanism to accomodate different shaft/gear diameters and lengths.

Walt

Thanks Walt. The centre in the drive shaft is not exposed (covered by snout)to engage the conical head of tacho meter. And hence we are unable to check the speed by engaging the tacho.

Thanks.