Noise reduction box and ventilation therapy apparatus

Abstract

A noise reduction box and a ventilation therapy apparatus. The noise reduction box includes a housing (10), a first flow guide pipe (23) and a second flow guide pipe (24). At least two chambers (15) are provided in the housing (10); the first flow guide pipe (23) and the second flow guide pipe (24) are both configured to guide the flow of a gas, so that the gas flows from one of the chambers (15) to another one of the chambers (15). When a gas pressure in a reference chamber is less than or equal to a reference gas pressure threshold, the first flow guide pipe (23) guides the flow of the gas; and when the gas pressure in the reference chamber is greater than the reference gas pressure threshold, the first flow guide pipe (23) and the second flow guide pipe (24) jointly guide the flow of the gas. The noise reduction box can change a gas path according to a change in the rotational speed of a gas pressurization unit, and has a better silencing effect; and the noise reduction box prolongs the service life of the gas pressurization unit while achieving noise reduction.

Dependencies are inferred from the claim text.