Belt type continuously variable transmission

A belt-type continuously variable transmission comprising:

• a drive pulley assembly mounted to a drive shaft;
• a driven pulley assembly mounted to a driven shaft;
• a belt wrapped around the drive pulley assembly and the driven pulley assembly;
• and
• a case assembly for accommodating the drive pulley assembly, the driven pulley assembly, and the belt;
• wherein the case assembly includes:
• a case body having a bottom wall portion joined to a housing of a drive device, and a peripheral wall portion surrounding the drive pulley assembly, the driven pulley assembly, and the belt;
• and a cover joined to the case body;
• and wherein an air-intake duct through which air from outside is taken into the case body and an air discharge duct through which the air is discharged are attached to the case body;
• the cover soley supports the drive shaft among the group comprising the drive shaft, the driven pulley assembly, and the driven shaft;
• a plurality of drive-side ribs are provided to extend radially from a drive-side center corresponding to a center axis of a drive shaft portion on an inner surface of the cover;
• a plurality of driven-side ribs are provided to extend radially from a driven-side center corresponding to a center axis of the driven shaft portion on the inner surface of the cover;
• a total number of the driven-side ribs is greater than a total number of the drive-side ribs.