has a flared head sized to correspond to the width of the first surface 8a of the filter 8 so that one rotation of either the filter cleaner 10 or the filter 8 relative to each other cleans the entire filter the tip opening 10a is attached at one end to a first horizontal portion 10b extending horizontally toward the center region 14 a vertical portion 10c extends vertically upward from the fan motor 9 generally transverse to the first horizontal portion 10b an elbow portion 10e joins the first horizontal portion 10b and the vertical portion 10c a t shaped portion 10f extends vertically upward from vertical portion 10e such that second horizontal portion 10d is attached thereto and is located in parallel alignment above first horizontal portion 10b in this embodiment portions 10a 10b 10c and 10e form an integral unit which is rotatably driven by driving means 11 enabling the filter cleaner to rotate around vertical portion 10c to clean along the first surface 8a of the filter 8 it is to be understood that in an alternative embodiment shown in fig5 described below in greater detail the filter cleaner 10 39 remains stationary while the drive means 11 39 rotates the filter 8 39 relative thereto the drive means 11 includes a first spur gear 17 mounted on a shaft end of a gear motor 16 a second spur gear be is mounted on the periphery of the vertical portion 10c of the cleaning filter 10 a motor stand 19 surrounds the spur gears 17 and 18 and provides support for a center member 20 on which the gear motor 16 is mounted this arrangement of the gear motor 16 allows the gear motor 16 to revolve at a.