Dumbwaiter

Dumbwaiters are small freight elevators (or lifts) intended to carry objects 
rather than people.
 
Dumbwaiters are found within modern structures, including  commercial, public and private buildings. They are often connected between multiple floors. When installed in restaurants, schools, kindergartens, hospitals, retirement homes or in private homes, the lifts generally terminate in a kitchen.

The term seems to have been popularized in the United States from 1840s, 
after the model of earlier “dumbwaiters” now know as serving trays and 
lazy Susans.