Abstract: A vent device includes at least one stage ventilation assembly, each stage of the at least one stage ventilation assembly includes an inner layer element and an outer layer element. An air duct is formed between the outer layer element and the inner layer element, and the air duct has an air duct outlet. Each stage of the at least one stage ventilation assembly has an air duct open position and closed position. The outer layer element and the inner layer element are configured to be able to move along the first direction relative to each other between the air duct open position and closed position. In the air duct closed position, the inner layer element closes the air duct outlet, and in the air duct open position, the inner layer element opens the air duct outlet.

Abstract: A vent device includes at least one stage of a ventilation assembly, each stage of the ventilation assembly includes an inner layer element and an outer layer element. An air duct is formed between the outer layer element and the inner layer element, and the air duct has an air duct outlet. Each stage of the ventilation assembly has an air duct open position and closed position. The outer layer element and the inner layer element are configured to be able to move along the first direction relative to each other between the air duct open position and closed position. In the air duct closed position, the inner layer element closes the air duct outlet, and in the air duct open position, the inner layer element opens the air duct outlet.