When did kevin woolfolk made his invension?

There's no widely recognized invention attributed to Kevin Woolfolk. It's possible that you're thinking of someone else or that his invention is not widely known.

To help me find information about a possible invention, please provide more context:

* What kind of invention are you thinking of? (e.g., a medical device, a software program, a gadget)

* What is the approximate year or time period you believe the invention was made?

* Is there any additional information about Kevin Woolfolk, such as his field of expertise or location?

With more details, I can try to locate information about any inventions associated with Kevin Woolfolk.