If I remove my apple ID account on my Iphone 4s, does it delete the data on iCloud on that device only?
Removing your Apple ID account from your iPhone should have no affect on the data stored in iCloud. You can safely sign out of iCloud and related services from your iPhone. In doing that, read the prompts to confirm that you are not as they look rather ominous at times, but should only be telling you that data will be removed from the phone.