Abstract: An outer shell structure surrounds a heat exchange unit formed of plates, which has first to third pairs of opposite planes. The structure has opposite end walls, opposite first walls and opposite second walls, and gap closure members. The end walls are placed on the pair of first opposite planes of the heat exchange unit. The first walls having openings are placed outside apart from the pair of second opposite planes of the heat exchange unit and connected water-tightly to edges of the end walls. The second walls having openings are placed outside apart from the pair of third opposite planes of the heat exchange unit and connected water-tightly to edges of the end walls. The gap closure members close a gap between the first walls and the heat exchange unit and a gap between the second walls and the heat exchange unit.

Abstract: Heat exchange plates are stacked. The stacked plates are transported to a table. A pressing member is placed on an uppermost plate of the stacked plates to apply a pressing force to them. A shell is placed to surround a space encompassing the stacked plates to isolate the plates from an outside. A gas is discharged from the space encompassing the plates to the outside through gas supply/discharge sections provided on the table.

Abstract: Heat exchange plates are stacked, with a pressing force applied to the plates so as to maintain parallelism of them and prevent deformation of them during a diffusion bonding process. The stacking condition is maintained and adjacent plates come into contact with each other at projections and peripheral edges. Space surrounding the contact portions of the plates is put in a vacuum or low pressure state in which only an inner gas atmosphere exists. The plates are kept at a temperature at which the diffusion bonding occurs by a predetermined period of time to diffusion-bond portions of the plates, which are only brought into contact with each other and have not been bonded together.

Abstract: A heat exchange plate has a main heat transfer section and a fluid guiding portion having first and second sub-patterns of irregularity, respectively. The second pattern of irregularity includes projections and recesses. At least a part of straight or curved lines along which the projections and recesses are aligned has an end located in a predetermined position of an edge of the plate, which forms at least one of inlet and outlet portions and another end that does not coincide with the end located on a boundary between the fluid guiding portion and the main heat transfer section.

Abstract: A heat exchange unit is composed of rectangular heat transfer panels with terraced flat portions, combined in parallel and integrally with each other to form first and second spaces. Outer and inner reinforcement members having respective serrations are welded to the panels so that the serrations are inserted into gaps between the heat transfer panels. The outer and inner reinforcement members are made of the same material as the heat transfer panels and have a larger thickness than the heat transfer panel, so as to bear high heat input given during the welding. The heat input caused by welding can be increased to enable portions of the heat transfer panels to be melted rapidly.

Abstract: A heat exchange unit includes first and second plates, which is identical to each other in configuration in a peripheral area thereof, but different from each other in a central irregularity pattern section. The irregularity pattern section has a projection-recess pattern on its surface and a recess-projection pattern corresponding thereto on another surface. These patterns are different from each other in configuration. The projection-recess pattern of the first plate has a reverse relationship in projections and recesses to the projection-recess pattern of the second plate so as to be symmetrical to each other. The first and second plates are placed alternately one upon another so that the peripheral areas of the first and second plates are directed to a same direction and projections of the irregularity pattern section of the first plate come, on peaks thereof, into contact with projections of the irregularity pattern section of the second plate.

Abstract: A heat exchange unit includes first and second plates, which are identical in configuration in a central irregularity pattern section, but different in configuration in a peripheral area. The first plate has first terraced sections projecting outward relative to a remaining part having a first flat section. The second plate has a second terraced section projecting outward relative to a remaining part having a second flat section. The first and second plates are placed alternately one upon another so that surfaces of said irregularity pattern sections face a same direction. The first terraced sections of the first plates come into contact with the second flat sections of the second plates and the first flat sections of the first plates come into contact with the second terraced sections of the second plates. The first and second plates are welded to each other at contact areas.

Abstract: A heat exchange unit includes metallic heat transfer members combined with each other. Each heat transfer member has a heat transfer face having opposite surfaces with which first and second heat exchange fluids come into contact, respectively. Welded-together flat portions of the heat transfer members are inserted into a fitting hole of an end plate. The fitting hole substantially coincides with an end shape of the combined heat transfer members and is sized to slidably receive welded-together flat portions such that the end plate and the received, welded-together flat portions contact each other. After insertion, the heat transfer members are welded to the end plate along the fitting hole so that, at the welded region, the heat transfer members and the end plate form an integral construction.

Abstract: A heat transfer member for a heat exchanger, is press-formed of a metallic thin sheet material into a prescribed shape by means of molds of a press forming device so that the heat transfer member has on at least one portion thereof a heat transfer face having opposite surfaces, which are to be brought into contact with heat exchange fluids, respectively. The heat transfer face comprises at least one set of irregularity patterns arranged in a row.

Abstract: A seam welding apparatus enables, even when metallic sheets are arranged in a line in a short distance, the welding electrodes to come into contact only with the metallic sheet to be welded, so as to provide a reliable welding of the metallic sheets to form connected portions having high strength. The roller electrode 20, which has on its outer peripheral portion the conical electrode surface 21, is supported by the central axis inclined relative to the surface of the metallic sheet 50 to be welded, and there is provided the stationary electrode 30 in which the portion including the flat electrode surface 31 has the smaller thickness. The electrode surface 21 of the roller electrode 20 is brought into contact with the surface of one of the metallic sheets 50 to be welded, while bringing the electrode surface 31 of the stationary electrode 30 into contact with the surface of the other metallic sheet 50.

Abstract: A heat exchange plate having a pattern of irregularity is combined with the other plates to constitute a heat exchanger. The plate has main and intermediate protrusions. The main protrusions have a quadrangular pyramid shape with a top, first and second pairs of side surfaces. The first and second pairs of side surfaces face each other in the first and second directions. The main protrusions are aligned in these directions so that these pairs of surfaces of the main protrusion face the corresponding surfaces of adjacent protrusions. The intermediate protrusion is placed between adjacent main protrusions and has opposite foot portions and a head ridge placed between them. The foot portion is placed in a lowermost position at which ridgelines of the adjacent two main protrusions intersect. The head ridge is placed in a level higher than the foot portions, but lower than the top of the main protrusion.

Abstract: A press-forming apparatus comprises a pair of press-forming units detachably secured to movable and stationary units facing each other, respectively. A metallic material is subjected to a press-forming through the press-forming units and then discharged therefrom as a heat transfer member for a heat exchanger. Each of the press-forming units comprises (i) a main forming section for forming on the material a heat transfer face with a corrugated portion, (ii) a pair of first subsidiary forming sections disposed on upstream and downstream sides of the main forming section so as to be adjacent thereto in the feeding direction of the material and (iii) a forming section-support base member detachably supporting the main forming section and the first subsidiary forming sections.

Abstract: A method for manufacturing a heat transfer member comprises the step of subjecting a material to be worked, which is made of a metallic thin sheet, to a press forming utilizing a press-forming device to form a heat transfer member for a heat exchanger. The heat transfer member has on at least one portion thereof a heat transfer face that has opposite surfaces, which are to be come into contact with heat exchange fluids, respectively. The press-forming device comprises a pair of main molds for forming the heat transfer face on the material, which is to be conveyed in a single feeding direction, and two pairs of first auxiliary molds, which are disposed on upstream and downstream sides of the pair of main molds in the feeding direction of the material, so as to be exchangeable.

Abstract: A method for manufacturing a heat transfer member comprises the step of subjecting material to be worked, which is made of a metallic thin sheet, to a press forming utilizing upper and lower molds of a press-forming devices to form the material to be worked into a shape having prescribed irregularities, thereby preparing a heat transfer member for a heat exchanger. An elongated material is used as the material to be worked. A press-forming device is provided with molds each having a length shorter than the elongated material to be worked.

Abstract: A method for manufacturing a heat transfer member comprises the steps of: subjecting elongated materials to be worked, which are made of metallic thin sheets, to a continuous press forming utilizing a plurality of press-forming devices to form heat transfer faces each having a prescribed shape, while transferring the materials in a prescribed feeding direction, which is in parallel with a longitudinal direction of the materials; and welding two materials, which have been subjected to the press forming, of the elongated materials together utilizing a welding device to form a heat transfer member having substantially a tubular shape.