Belt transmission having air cooling function

A belt transmission arranged in a vehicle having a body defining therein a substantially closed space, said belt transmission comprising:

• a drive pulley;
• a driven pulley;
• a belt engaging with said drive pulley and said driven pulley;
• a casing accommodating said drive pulley, said driven pulley, and said belt,
• said casing being substantially horizontally disposed and including a wall located at a downstream side in air flow of said casing, said wall extending substantially transversely and vertically of said casing;
• air inlet port means having an air inlet port opening in said substantially closed space for introducing fresh air therein into said casing;
• air outlet port means provided in said casing for discharging air from said casing, said air outlet port means comprising:
• a first communication hole formed in said wall and opening in said casing at an upper location,
• an air discharge passage extending along said wall substantially transversely and substantially vertically of said casing,
• a second communication hole formed in said casing at a level lower than said first communication hole, and
• an air outlet port opening in the atmosphere, said air discharge passage communicating with the interior of said casing through said first communication hole and with said air outlet port through said second communication hole, respectively,
• said first communication hole and said second communication hole being offset transversely of said casing;
• fan means provided on at least one of said drive pulley and said driven pulley and rotatable in unison therewith;
• said air inlet port means and said air outlet port means being disposed such that fresh air is sucked into said casing through said air inlet port means as said fan means rotates, to cool at least said drive pulley, said belt and said driven pulley, and is discharged from said casing through said air outlet port means.

A belt transmission arranged in a vehicle having a body defining therein a substantially closed space, said belt transmission comprising:

• a drive pulley;
• a driven pulley;
• a belt engaging with said drive pulley and said driven pulley;
• a casing accommodating said drive pulley, said driven pulley, and said belt, said casing being substantially horizontally disposed and having:
• a first lateral wall and a second lateral wall arranged opposite each other, and
• an inner transverse wall and an outer transverse wall, both transverse walls extending between said first and second lateral walls at a downstream side in air flow of said casing;
• air inlet port means having an air inlet port opening in said substantially closed space for introducing fresh air therein into said casing;
• air outlet port means provided in said casing for discharging air from said casing, said air outlet port means comprising:
• a communication hole formed in said inner transverse wall and opening in said casing,
• an air discharge passage defined between said inner transverse wall and said outer transverse wall, said air discharge passage communicating at one end with the interior of said casing through said communication hole, and
• an air outlet port opening in the atmosphere and communicating with another end of said air discharge passage,
• said inner transverse wall and said outer trnasverse wall each being formed integrally on at least one of said first and second lateral walls;
• fan means provided on at least one of said drive pulley and said driven pulley and rotatable in unison therewith;
• said air inlet port means and said air outlet port means being disposed such that fresh air is sucked into said casing through said air inlet port means as said fan means rotates, to cool at least said drive pulley, said belt and said driven pulley, and is discharged from said casing through said air outlet port means.

A belt transmission arranged in a vehicle having a body defining therein a substantially closed space, said belt transmission comprising:

• a drive pulley;
• a driven pulley;
• a belt engaging with said drive pulley and said driven pulley;
• said driven pulley having a pair of driven face elements disposed concentrically and opposite each other and carrying said belt wound thereon,
• said driven face elements each having a plurality of through holes arranged circumferentially thereof,
• one of said driven face elements being axially movable relative to the other driven face element,
• said through holes being disposed radially inward of an inner peripheral surface of said belt even when said one driven face element is located at a maximum distance from the other driven face element;
• a casing accommodating said drive pulley, said driven pulley, and said belt;
• air inlet port means having an air inlet port opening in said substantially closed space for introducing fresh air therein into said casing;
• air outlet port means provided in said casing for discharging air from said casing;
• fan means provided on said driven pulley and rotatable in unison therewith;
• said air inlet port means and said air outlet port means being disposed such that fresh air is sucked into said casing through said air inlet port means as said fan means rotates, to cool at least said drive pulley, said belt and said driven pulley, and is discharged from said casing through said air outlet port means.

A belt transmission arranged in a vehicle having a body cover, a seat arranged on said body cover, and a substantially closed space defined by said body cover and said seat, said belt transmissiion comprising:

• a drive pulley;
• a driven pulley;
• a belt engaging with said drive pulley and said driven pulley;
• a casing accommodating said drive pulley, said driven pulley, and said belt;
• air inlet port means having an air inlet port opening in said substantially closed space for introducing fresh air therein into said casing;
• air outlet port means provided in said casing for discharging air from said casing;
• fan means provided on at least one of said drive pulley and said driven pulley and rotatable in unison therewith;
• said air inlet port means and said air outlet port means being disposed such that fresh air is sucked into said casing through said air inlet port means as said fan means rotates, to cool at least said drive pulley, said belt and said driven pulley, and is discharged from said casing through said air outlet port means.