ELECTROSTATIC AIR FILTER
An electronic air filter having a plurality of electrodes supported by rigid fixtures that are attached to a common case. The rigid fixtures that support the electrodes with different electrical potentials are attached to each other or to a common body in a way that increases or maximizes the creeping discharge path along the surface. Even conductive contaminants do not, therefore, provide an electrical shortage between the electrodes.
1 . An electrostatic air filter comprising:
a case formed by walls and having an open air inlet and an open air outlet;
at least two electrode sets having different electrical potentials in which each electrode set is assembled on separate rigid fixtures;
the rigid fixtures are secured to the case at separate spots; and
wherein said separate spots are spaced apart sufficiently to establish an extended creeping distance.
2 . An electrostatic air filter according to claim 1 further comprising a repelling electrode set and a corona electrode set and wherein said repelling electrode set is at or near the electrical potential of said corona electrode set.
3 . An electrostatic air filter according to claim 1 wherein said collecting electrode set has an electrical potential at or near an electrical potential of said exciting electrode set.
4 . An electrostatic air filter according to claim 1 wherein one or more electrode sets has an electrical potential close to ground.
5 . An electrostatic air filter according to claim 1 wherein said members of at least one of said groups of the electrodes are supported by common rigid fixtures on the opposite sides of said members.
6 . An electrostatic air filter according to claim 1 wherein a surface of said case walls is winding or corrugated or convoluted in order to increase the creeping discharge path along the surface of the walls.
7 . An electrostatic air filter according to claim 1 wherein a surface of said rigid fixture is winding or corrugated or convoluted in order to increase the creeping discharge path along the surface of the fixture.
8 . An electrostatic air filter according to claim 1 , where the electrode sets are at least two of: a collecting electrode set; a corona electrode set; an exciting electrode set; and a repelling electrode set.
9 . An electrostatic air filter according to claim 8 wherein one of said electrode sets is a corona electrode sets and wherein said corona electrode set comprises one or more thin conductive wires mounted to traverse an air flow path in parallel and defining a plane that is substantially perpendicular to a principal air flow direction.
10 . An electrostatic air filter according to claim 8 wherein said collecting electrodes and said repelling electrodes are corrugated members parallel to each other and to the principal air flow direction.
11 . An electrostatic air filter according to claim 8 wherein one of said electrode sets is an exciting electrode set and said exciting electrode set comprises one or more electrically conductive members in a plane that is parallel to a plane defined by a corona electrode set.
12 . An electrostatic air filter according to claim 11 wherein said exciting electrode set further comprises an electrically conductive air penetrable web.
13 . An electrostatic air filter according to claim 11 wherein said exciting electrode set has an electrical potential at or close to ground.
14 . An electrostatic air filter according to claim 8 wherein one of said electrode sets is a collecting electrode set and said collecting electrode set comprises a plurality of collecting surfaces mounted parallel to each other and substantially parallel to a principal air flow direction.
15 . An electrostatic air filter according to claim 14 wherein one of said electrode sets is a repelling electrode sets and said are repelling electrode set further comprises a plurality of repelling surfaces mounted parallel to each other and in locations flanked by collecting surfaces.
16 . An electrostatic air filter according to claim 14 wherein said collecting electrodes have apertures and are connected to each other via rigid fixtures;
said repelling electrodes have apertures and connect to each other via rigid fixtures;
wherein said repelling and collecting electrodes are mounted in alternating order parallel to each other;
wherein said rigid fixtures of said collecting electrodes go through said apertures of said repelling electrodes' members;
wherein said rigid fixtures of the repelling electrodes go through the apertures of the collecting electrodes' members;
wherein said case has two inner walls and two outer walls on opposing sides;
said walls are substantially parallel to the collecting electrodes and separated from each other by air gaps;
said inner walls have apertures; said rigid fixtures of said collecting electrodes group are secured to the outer wall on one side and go through the apertures of the inner wall on that side;
said repelling electrodes group fasteners secured to the outer wall on the other side, and then go through the apertures of the inner wall on that other side; and
the dimensions of said apertures in the electrodes and inner walls allow said rigid fixtures to go through them without touching corresponding electrodes and walls.
17 . An electrostatic air filter of according to claim 15 further comprising a shield positioned to block gaps between the inner and outer walls from the airflow.
18 . An electrostatic air filter electrode assembly comprising:
an accordion rack;
a first group of electrodes mounted in parallel on said accordion rack; and
a second group of electrodes which operate at a different potential than the first group of electrodes mounted in parallel on said accordion rack;
wherein said electrodes are mounted in an alternating sequence.
19 . An electrostatic air filter according to claim 18 wherein said accordion rack further comprising pivot points securing members to said accordion rack and members that extend beyond said pivot points; and an additional electrode set mounted on extended portions of said extended members.
20 . An electrostatic air filter according to claim 18 wherein a surface of said bars is winding or corrugated or convoluted in order to increase the creeping discharge path along the surface of the bars.
21 . An electrostatic air filter according to claim 11 , wherein the exciting electrode is located downstream with regard to the corona electrode.