I have an invention let's say a tea pot. I saw a patent with sweeping claims about tea pots. This specific patent is a tea pot that needs a lid to boil and I came up with a tea pot that doesn't need a lid to boil water. However that patent sweeps so many claims including not having the lid. But the drawings and design show the lid. Secondly I notice from this design, it is almost impossible to manufacture this tea pot. But my tea pot can be manufactured easily and doesn't need a lid to boil. Also in the claims this patent doesn't refer to the lid as a function to broaden the claims. But I know it is designed just for that purpose even it doesn't mention. Almost making my design very obvious. Just take the lid off. Under these conditions is my invention patentable?
It does have to be novel and not obvious over the prior art, but if your invention (the parts that distinguish your teapot) provides advantages like an easy method of manufacturing and a capability for allowing boiling without the lid, then you need to draft claims that focus on the elements and construction not shown in the prior art giving rise to those advantages. If the prior art does not teach teapots having these advantages, you should have some scope open.
Of course, the prior art may teach lidless boiling, but you have to focus on the elements and construction showing a significant improvement in that result. In this case, your disclosure should also show evidence of the improved boiling capability, and any other indications of non-obviousness.
So if the prior art is "a teapot comprising a chamber for holding water and a heat imparting surface in contact with a heat source for heating the water in the chamber to boiling;" you might get claims for "said teapot including a heat conducting projection in contact with said heat imparting surface and extending into said chamber for increasing said heating of said water and reducing the time to boiling."