To suppress increase in door operating force due to the deformation of a film member by means of wind pressure, in this air passage switching device which uses a film type rotary door.
A bend 92k is installed in at least one end side of both ends in the circumferential direction of a film member 92, and this bend 92k is locked to a rotary door 91, while a bend radius R of this bend 92k should be set up in a range of 6 to 8 mm. Therefore, in proportion as enlarging this bend radius R, load of wind pressure is dispersible in a wide range, and thereby an amount of deformation in a circular angular part 92f of the bent 92k becomes lessened, so door operating force is thus reducible. Accordingly, the bend radius R should be set to more than 6 mm. In addition, in order to secure a sealing effect, an upper limit of the bend radius R should be set to less than 8 mm.
OSAKI KATSUYUKI
KAMIYA TOMOHIRO
Next Patent: AIR CONDITIONER FOR AUTOMOBILE