The present invention relates to a device in connection with an electrostatic precipitator for cleaning of a gaseous medium from particles being present in said medium.

In conventional arrangements the filters of the type in question that are present on the market include an ionizing portion and a separating portion. In the ionizing portion the particles passing through said portion are charged and in the separating portion the charged particles are then separated. The ionizing portion often includes a corona wire that is subjected to a high potential and earthed plates. If the potential upon the wire is sufficiently high charging of the corona will take place and the ions that then are generated will be driven, from the wire towards the plates, in a field that is located between the wire and the plates. On their way the ions will meet particles in the passing medium and charge said particles. The charged particles are carried by the medium, e.g. an air stream, further to the separating portion where they due to the field between the charged and earthed plates are driven towards the earthed plates to be deposited upon these plates.

The aim of the present invention is to provide a device of the type mentioned above where the arrangement mentioned above in connection with an electrostatic precipitator is simplified to an essential degree and is made more efficient. The characterising features of the invention are defined in the appended claims.

Thanks to the invention a device is realised that in an excellent way achieves its aims simultaneously as it is also both simple and cheap to produce. This is effected by integrating the ionizing portion and the separating portion of the filter with each other. Thereby a filter is achieved that both is more compact and more efficient than previous filters. The invention is described more in detail with the assistance of a preferred embodiment and reference to the accompanying drawing, where

Fig 1 schematically shows a conventional arrangement in connection with an electrostatic precipitator

and Fig 2 schematically shows an arrangement according to the present invention in connection with an electrostatic precipitator.

From Fig 1 can be learnt how a known electrostatic precipitator is designed and functions. This precipitator 1 includes an ionizing portion 2 having a corona wire 3 where the particles of a medium, e.g. an air stream, are charged. Further the precipitator 1 includes a separating portion 4 including several charged plates 5 and earthed plates 6, that are alternatively arranged nearby each other.

In Fig 2 a preferred embodiment of the present invention is shown, the ionizing portion 2 being integrated with the separating portion 4. The plates, both charged and earthed 5 and 6 respectively, can be of a material having high electrical resistivity, so called high-ohmic material, e.g. paper. At the edge 7 of the charged plate 5 the "ionizing points" or the ionizing wire are applied, said points or wires can be of carbon fiber, alumina chips etc. A high voltage is applied to the edge, said edge then will function as corona wire. The rest of the plates 5 are charged by the high voltage, the effect being that the particles charged in the ionizing portion 2 are driven towards the earthed plates 6 and are deposited upon these.