US Patent 7258715 Air cleaner

An improved filter element for use in an electrostatic precipitation air cleaning device, the filter element including rod electrodes arranged through a stack of alternating fluted plastic sheets and plate electrodes. Successive plate electrodes are arranged to make contact with an alternating one or the other of the rod electrodes. The plate and rod electrodes may be composed of high impedance materials such as paper and plastic, respectively. An arrangement for removably inserting a filter element into an air cleaning device is provided. The arrangement also removably provides electrical connectivity between the filter element and the air cleaning device. The filter element can thus be readily removed and re-installed by a user.