Parallel point to plane electrostatic precipitator particle size sampler

Claim 1

An electrostatic precipitator for precipitating particulate matter from a volume of fluid, comprising: a housing having a chamber therein with an opening connecting said chamber with the volume of fluid so that said volume of fluid has free access to said chamber, a passageway connected to said chamber of said housing extending from said chamber to a point without said housing so that fluid entering said chamber through said opening exhausts said chamber through said passageway, a flat conductive collector electrode surface being supported by and separate from said housing and being positioned within said chamber, an elongated electrode axially of the chamber having a point at one end and a long axis passing through said point, said elongated electrode being supported by said housing and being positioned within said chamber in spaced-apart relationship with said flat conductive surface and with said long axis parallel thereto, said point being abreast of said flat conductive surface and directed toward said opening with the distance between said point and said volume of fluid through said opening being less than or equal to two-thirds of the narrowest cross-sectional dimension of said opening, and voltage supply means coupled to said electrode and said surface to provide a voltage sufficient to cause a corona discharge therebetween, whereby particulate matter in the fluid contacting said corona discharge is precipitated onto said surface.