Wenderoth, Lind & Ponack
Filter apparatus having a casing with improved structure for holding filter media
 A filter apparatus includes a box-shaped casing formed by connecting peripheral edges of first and second casing members each having a concavity and a filter composed of first and second filter media placed one upon the other and having respective peripheries held between substantially the entire peripheral edges of the first and second casing members such that the filter assumes the shape of a bag when disposed in the casing. The casing has a suction port and an exhaust port each communicating between the interior and the exterior of the casing. The filter communicates with the exterior of the apparatus through the suction or exhaust port of the casing. The first and second filter media have respective through holes and are closely adhered together at peripheral portions of the respective through holes. 
Honda Giken Kogyo Kabushiki Kaisha Toyo Roki Seizo Kabushikikaisha
F B
F01M B01D
additional inventional
Shunichi Kyoji Naomi Hiroaki Keiichi
Nogami Kitajima Muramatsu Yamashita Katagiri