"Food vending machine" covers several different devices. Each holds a different kind of product.
A food vending machine is usually one of three devices: a spiral machine with packaged snacks, a vending cooler with sandwiches, salads, and meals, or a carousel machine with meals in containers. The right format depends on whether people need a quick snack or a full meal.
Spiral machine
Bars, chips, cookies, nuts, and bottled drinks. Long-shelf-life products that handle the drop into the bin.
Vending cooler
Sandwiches, wraps, salads, heat-up meals, yogurts, and drinks. The customer takes the item after paying. The page on vending coolers (publisher's site) has examples.
Carousel machine
Meals in containers and delicate items, served through a door instead of dropped.
FAQ
Which format is best for meals? Vending coolers and carousel machines are more common for full meals.
Does vending food need heating? Some meals do – the producer says so on the package.