What is this houseplant called?

I was wondering if you could tell me what the name of my plant. It grows very large. I always thought it was an elephant plant but when I searched Google I can’t find any images that look the same. A few years ago I had an identical one but with hairy leaves. The leaves on this one are smooth.
I wanted to know what temperature these plants like. I moved it from the house into my conservatory and it didn’t seem to like the heat and I nearly lost it. It has recovered well and has been out on the patio for the summer months, but would it stand a frost? (although I have brought it inside now)