| 摘要 |
PROBLEM TO BE SOLVED: To provide a compact air filter unit capable of simply and safely replacing a main filter.SOLUTION: An air filter unit is equipped with a main filter, a prefilter, and a casing. The prefilter has a pair of rollers separated from each other, and a prefilter filtering material. The prefilter is configured to pull out an unused area of the prefilter filtering material from one of the rollers to move the unused area to a front surface of the main filter, and make a used area of the prefilter filtering material wound by the other roller. The casing has a holding frame which holds the main filter so as to allow an air flow passing a passage to pass through the main filter, and a pressing mechanism which is arranged in a clearance in the air flow direction between the main filter and the holding frame and presses the main filter on the holding frame.SELECTED DRAWING: Figure 1 |
