What makes you cry?

a terrible torture

Ah, I see. Neither yoga nor "restraint methods" are involved here; the patient will simply lose consciousness from the pain shock. The body will be in no condition to produce tears. Yes, it's a natural process, but it depends on the person's emotional state. Tears are meant to alleviate emotional discomfort due to the substances they contain. In your case, the person will scream loudly, if they can, until they fall silent. Interestingly, and rather little known, the person in your example will only die when the mechanism returns to its original position.
Yes, facts. Weaklings and nerds cry from pain: a whiner's eyes will water even if they simply trip or stub their toe on a table leg, while the eyes of a pompous and courageous general will be completely dry, even as a Tyranid gnaws off his leg.