Just before the quoted passage, the narrator says a whistling going "Don!" happens at the same time as he stumbles and ends up stooped. Then:
もちろん、いくら昔の話でも発車のベルは「ドン!」などとは鳴らないし、発車のベルが人を突き飛ばすこともない。
My attempted translation:
Of course, though this happened a long time ago, it couldn't be possible that the bell would go “Don!” and send someone flying.
Here I assume こともない means "it's not possible/the case that..." Is this correct?