"蜗轮减速机" can be translated as "worm gear reducer" or "worm reduction gearbox".
"Worm gear reducer" is a common and direct translation, emphasizing the use of a worm gear mechanism for speed reduction.
"Worm reduction gearbox" is also accurate, highlighting the gearbox's function of reducing speed through a worm gear setup.
Both expressions are widely used in engineering and technical contexts to refer to this type of speed reduction device.