Abstract: A first deflection member and a first wall produce a first air flow therebetween. The first deflection member and a second wall produce a second air flow therebetween. The first deflection member switches between a first state, in which the first air flow is higher in flow rate than the second air flow, and a second state other than the first state. A guide wall is a part of the first wall to bend the first air flow in the first state to guide the first air flow away from the second wall. A second deflection member on the downstream side of the first deflection member causes deflection of the second air flow to be away from the second wall in the first state. In the second state, the second deflection member reduces or prohibits the deflection of the second air flow.