71 that pivots around pivoting point 73 located on lever 70 elastic element such as spring 74 between levers 70 and 71 maintains tension on filament 20 and compensates for change in required length of filament 20 during movement of lever 70 along the cleaning path 48 of course a single u shaped lever made of elastic material may serve the same purpose high ionizing voltage is supplied to filament 20 through support 15 cleaning of the filament 20 is accomplished by rotating the support structure 10 while holding the filament 20 in fixed position while sliding the supports 11 13 14 15 over the filament or by rotating lever 70 to slide the filament 20 through the supports 11 13 14 15 in fixed position one or more of the supports 11 can protrude radially outside of the support structure 10 to facilitate both ease of rotating and additionally can intrude radially and be shaped as vanes for redirecting collimating the ionized air stream formed by the apparatus as described of course the pivoting point 72 on lever 70 can also be placed outside the perimeter of support structure 10 movement of support structure 10 or of lever 70 can be performed manually or via an actuator such as solenoid 90 mounted on support 5 to apply force 49 to rotate the lever 70 referring now to fig5 there is shown a detailed view of the support structure and cleaning mechanism according to another embodiment of the present invention the support structure comprises a body.