Variable flow vent assembly for a conduit mask

A vent assembly for a patient interface for delivering a flow of breathable gas at a positive pressure to an airway entrance of a patient, the vent assembly comprising:

• a vent body at least in part defining a vent chamber configured to contain gas at the positive pressure, the vent body being configured to define:
• a first inlet on a first side of the vent body, the first inlet being configured to receive a first inlet flow of breathable gas into the vent chamber;
• a second inlet on a second side of the vent body, the second side being opposite the first side, the second inlet being configured to receive a second inlet flow of breathable gas into the vent chamber;
• an opening configured to allow exit of the flow of breathable gas from the vent chamber for delivery to the airway entrance and to receive a flow of exhaled gas from the patient into the vent chamber;
• and
• a plurality of vent holes configured to allow a vent flow of exhaled gas from the vent chamber to ambient, wherein the plurality of vent holes comprises;
• a plurality of active vent holes formed in a respective seat portion of a first seat portion and a second seat portion of the vent body, and
• one or more passive vent holes;
• wherein the vent assembly further comprises a valve configured to adopt a first configuration and a second configuration, wherein the valve at least partially blocks the plurality of active vent holes by a different amount in the first configuration compared to the second configuration, and
• wherein the valve is configured so that the configuration adopted by the valve is based on the positive pressure of gas in the vent chamber.