| 摘要 |
In order to ensure sufficient rigidity and to facilitate molding work, one surface of a filter body (11) has oil passages (12a, 12b, 12c) etched to a depth of half the plate thickness, and the other surface of the filter body (11) has through-holes (13) formed by etching at the positions in which the oil passages (12a, 12b, 12c) are formed. |
