provided by the air passage 417 below the case 41 the air cleaner element 42 has a hollow center bottom to merely receive the placement of the locking member 414 and the locking pillars 416 of the case 41 a trap 421 usually in the form of a piece of filtration cotton or paper is provided to the peripheral of the air cleaner element 42 a resilient washer is mounted to the lower circumference of the air cleaner element 42 and a locking hole 423 is provided on top of the air cleaner element 42 at where in relation to the locking pillar 416 the rectangular cover 43 properly covers up the case 41 and a through hole 431 is provided on top of the cover 43 at where in relation to the locking pillar 416 to permit the insertion of a fastener 44 for locking purpose as illustrated in fig5 upon assembling the air cleaner 4 of the present invention the air cleaner is mounted to the locking member 414 inside the case 41 the locking hole 423 on top of the air cleaner element 42 is disposed at where in relation to the locking pillar 46 while the resilient washer 422 below the air cleaner element 42 is flushed on the case 41 to avoid overflow of the clean air the.