Abstract: First and second communicating holes are formed in a first formed plate 11, and first and second communicating holes are also formed in a second formed plate 12. The first and second formed plates 11 and 12 are joined to each other to form a joined body 8. When a plurality of joined bodies 8 are stacked, a heat exchanging section 7 is formed that is provided with a plurality of flow pipes 34 in which the first communicating holes are connected with each other in the stacking direction and the second communicating holes are also connected with each other. In the plurality of flow pipes 34 of the heat exchanging section 7, oil passage 35 in which engine oil flows in the stacking direction is formed, and further around the plurality of flow pipes 34, a plurality of cooling water passages 36 in which engine cooling water flows are formed.

Abstract: A laminated type oil cooler for cooling engine oil by using engine cooling water includes a heat exchanging portion for heat exchanging between the engine cooling water and the engine oil. The heat exchanging portion is formed by laminating a plurality of plates rotated by a predetermined angle with an adjacent plate, and each of the plates has first and second fluid holes and a fluid passage portion. The fluid passage portion communicates with the first fluid hole without communicating with the second fluid hole. The first fluid hole communicates with the second fluid hole of the adjacent plate to form two independent groups of fluid pipes. One group includes two fluid pipes for the engine oil, one pipe is connected to an inlet of an engine side bracket and the other pipe is connected to an outlet of the engine side bracket.

Abstract: A water-cooled oil cooler includes a laminated body formed by alternately piling up formed plates having cooling water passage openings and oil passage openings in the direction of plate thickness, and fin plates having cooling water passage openings and oil passage openings in the direction of plate thickness. A protrusion is projected from a passage wall of the cooling water passage opening of the fin plate into a cooling water passage. By setting the protrusion baser than the other part of the fin plate, the protrusion is made to serve as a sacrificial corrosion section to prevent the contact section from being precedently corroded.

Abstract: An oil cooler includes a heat exchanging core 40 which includes a stack of heat exchanging plates 40. Each of the heat exchanging plates 40 includes a first set of openings 61 and 62 and a second set of openings 65, 66 and 67. The openings 65, 66 and 67 in the second set construct rows which are spaced along the width W of the plates 40. The openings between the first and second sets are alternately arranged along a direction of the width W of the plates. The openings 61 and 62 in the first set are symmetrical about a central axis X--X, while the openings 65, 66 or 67 in each row are asymmetric about the axis X--X.