| 摘要 |
PURPOSE:To prevent the failure to mount a prefilter device by interfering the mounting of a main filter at a regular mounting position with the protrusion of a stopper into a mounting space for the main filter when the prefilter is removed. CONSTITUTION:A safety deice 15 inhibits the operation of an ionization part 8 and a blower 10 when a main filter 9 is not mounted. Then a stopper 21 which extrudes and retracts in a space for the main filter 9 of a main system 1, an operating member 22 which operates to protrude and retract a stopper 21, and a spring 23 which allows the stopper 21 to protrude and retract in a space 13 through the operating member 22 are provided. Further, it is designed so that if the stopper 21 protrudes in the space 13, the main filter 9 is prevented from being mounted. It is also designed that if the prefilter 7 is mounted at a regular position, the prefilter 7 is allowed to move out to an area outside the space by operating the operating member 22 resisting against the spring 23. Thus it is possible to prevent the failure to mount the prefilter. |
