There's not going to be another AI winter. The past AI winters occurred because people drastically underestimated how difficult AI would be. MIT (Seymour Papert specifically) thought computer vision could be solved by some graduate students as a summer project. Same story for other AI problems, e.g. NLP, speech recognition, general reasoning and inference, etc.

Once the difficulty of those problems started to be understood, of course funding dried up. Industry is focused on short-term ROI, so it's hard to get funding if the profits won't be seen for 50 years.

The difference is that now there's an entire string of profitable markets for solving near-term AI problems. AI is fundamental to the business models of some of the world's largest companies (i.e. Google). There's basically zero risk of an AI winter when we're on the verge of advanced robotics, Watson-style Q&A systems, self-driving cars, large-scale genomics, etc.

An AGI winter is another story, but most AI work isn't really focused on serious, full-scale AGI right now anyway. That winter never ended and is ongoing. Everyone is focused on incremental AI improvements because no one really knows what's required for full AGI, and are in the meantime hoping they'll hit on it while building on known techniques like deep learning, comp neurosci, etc.

tl;dr: As long as investors continue to see marketable products for new AI developments anywhere in the next ~10 years, funding won't dry up again.