Observation apparatus with push-through device

The present invention relates to a monitoring device 11, the monitoring device is arranged in the wall 3 of the furnace 1, and in particular takes the images of the incineration process in the above (1), the inner end (I ), between the outer end (E), at least one housing (13,17) and having a monitoring element (25) disposed in the housing (13,17), at least the inner end (I) and the outer end (E) The extended. The monitoring device 11 has a scraper unit 31 from being attached to the inner end of (I) of the deposits monitoring element (25) produced in the wall (3).