Caffey Surname (John Thomas)

I am researching the surname of Caffey. I have traced my roots back to John (Jake) Caffey-possibly John Thomas Caffey, b. abt 1690(Ireland), father of Michael Caffey b. abt 1720 in Belfast and came to the US as a young man.

I would also like to know if we have a coat of arms.

Any help you can give me would be appreciated.

Fran Foster