Check valve for ventilator

A check valve for a ventilator, comprising:

• a housing assembly, and
• a flow guide assembly;
• wherein the housing assembly defines a flow channel, and the flow channel defines an air outlet;
• wherein the flow guide assembly is disposed in the flow channel;
• the flow guide assembly comprises a first baffling sleeve and a second baffling sleeve;
• the first baffling sleeve and the second baffling sleeve are disposed in an axial direction of the flow channel in sequence;
• a first flow passing opening is defined in the first baffling sleeve;
• one side of the first baffling sleeve away from the first flow passing opening is inclined toward the air outlet;
• one side of the second baffling sleeve is inclined toward the air outlet;
• the second baffling sleeve faces the first flow passing opening;
• a projection of the second baffling sleeve on a horizontal cross section of the flow channel completely overlaps a projection of the first flow passing opening on the horizontal cross section of the flow channel.