Abstract: A condenser particularly for use in automobile air conditioning system, the condenser including a pair of headers having their inner spaces divided by partitions so as to form a cooling medium flow path in a zigzag patterns including an inlet side group of paths and an outlet side group of paths, side group of paths is 30 to 60% of that of the inlet side group of paths.

Abstract: A tube for heat exchangers is a flat tube which either includes a pair of plane walls which are spaced a predetermined distance from one another, the plane walls respectively having one lateral ends integrally connected to each other by a U-shaped bent portion, the plane walls further having their other lateral ends which abut against to be tightly secured to one another, or alternatively, the flat tube includes as the plane walls a pair of preformed plates having the abutted and soldered portions at both lateral ends. The tube further includes one or more curved lugs integral with and protruding inwardly from an inner surface of each plane wall, and the curved lugs respectively having innermost tops so that the innermost tops protruding from one plane wall bear against the inner surface of the other plane wall or against the innermost tops of the other curved lugs protruding from said other plane wall.

Abstract: An aluminum alloy for heat exchangers, the alloy, comprising a base compostion selected from a group consisting of Al-Mg-Si composition containing 0.1 to 0.8 wt % of Mg, 0.2 to 1.0 wt % of Si and 0.3 to 1.5 wt % of Mn; pure-Al composition; Al-Mg composition containing 0.05 to 1.0 wt % of Mg; and a Al-Zn composition containing 0.05 to 2.0 wt % of Zn. The alloy further comprises 0.01 to 0.3 wt % of Fe and/or 0.01 to 0.3 wt % of Ni, wherein the balance are aluminum of purity of 99.9% or higher and unavoidable impurities contained therein, and content of Cu as one of the impurities is controlled to be 0.05 wt % or less.

Abstract: A method is provided to braze aluminum materials to each other, the method comprising a step of producing a fluoride gas-containing atmosphere within a brazing oven. The method further comprises a step of brazing the aluminum materials, by heating said materials within said atmosphere melts. The fluoride gas-containing atmosphere is produced in the soldering oven: by introducing an inert gas and the fluoride gas through different passages; by introducing into the oven a mixture of the inert gas and the fluoride gas; or by heating a fluoride in a receptacle which is placed in the oven so as to gasify the fluoride within the oven.

Abstract: A method of making a brazeable metal pipe which has elliptical tube-insertion apertures and guide lugs extending from at least one of the opposite edges defining the minor axis of each aperture, with the guide lugs extending in the direction of insertion of flat tubes. The method in an embodiment comprises the steps of: bending a part of a raw strip, which may be previously embossed to form recesses, so as to provide a bulged portion arc-shaped in cross section and connected to at least one unbulged flat portions; pressing inwardly to form inward swells; subsequently punching each inward swell to provide the tube-insertion aperture so that at least one of the opposite edges located at ends of the minor axis of said aperture remains unpunched; and finally bending the at least one unbulged portions to produce the finished pipe.

Abstract: A tube for heat exchangers is a flat tube which either comprises a pair of plane walls which are spaced a predetermined distance from one another, the plane walls respectively having lateral ends integrally connected to each other by a U-shaped bent portion, the plane walls further having other lateral ends which abut against and are tightly secured to one another, or alternatively, the flat tube comprises a pair of preformed plates having abutted and soldered portions at both lateral ends. The tube further comprises one or more curved lugs integral with and protruding inwardly from an inner surface of each plane wall, and the curve lugs respectively have innermost tops so that the innermost tops protruding from one plane wall bear against the inner surface of the other plane wall or against the innermost tops of the other curved lugs protruding from said other plane wall.

Abstract: A heat exchanger comprises a plurality of flat tubes, a pair of hollow headers connected to both ends of each of the flat tubes in fluid communication with them, and at least one fastener secured to the headers. The fastener comprises at least one self-retainable embracing portion capable of resiliently engaging the exterior of the header to keep the fastener in place prior to brazing the components of the exchanger together. The fastener can be temporarily connected, without the aid of any special tools, on a heat exchanger body before brazing with a "one-shot" procedure, thus rendering easy the manufacture of the heat exchanger. Since special tools are unnecessary, a greater number of temporarily assembled heat exchangers can be accommodated in one oven, thus improving, to a remarkable degree, the productivity in manufacture of the heat exchanger.

Abstract: The ends of numerous tubes are connected to hollow headers so that they are in fluid communication with the headers. Slit shaped apertures are formed in the outside face of the headers in the direction of their circumference, and partititions are inserted through the apertures. Each partition is constructed out of two partition plates which fit into the header through the aperture in superimposed position. Alternatively, the partition plates may be connected integrally at one end so that their unconnected ends tightly contact the edges of the slit shaped aperture. The partitions are then braced to the header to become integral with it.

Abstract: An apparatus for automatically inserting a plug in and to a predetermined position therein a raw pipe such as an aluminum pipe which is to be drawn for instance in a drawbench. The apparatus comprises a suppport roller which supports a plug-supporting rod at its intermediate portion near to an end of the rod, the support roller bearing a lower surface of the portion and being movable along the plug-supporting rod. The apparatus further comprises a pipe-transporting device for transporting the raw pipe, which device grips both ends of the raw pipe so as to move it towards the plug-supporting rod in a direction in alignment with an axis of said rod. A pusher protrudes forward from the pipe-transporting device so that the device starts to carry the support roller at a given instant whereby the raw pipe is prevented from directly riding the support roller and is thus protected from being scratched, and forcible pressing of the plug onto an inner surface of the raw pipe being also avoided.

Abstract: A pipe centering apparatus is of such a structure that pipes of certain kinds such as aluminum short pipes transported by a conveyor are centered with their longitudinal centers aligned with each other, before the pipes are subjected to chamfering or other processes. The pipe centering apparatus in the invention comprises a pair of right and left gears in mesh with each other and rotatably mounted on a main frame, a pair of right and left racks respectively in mesh with the right and left gears, and a pair of right and left regulators respectively secured to the right and left racks so as to come into contact with ends of the pipes, wherein the gears are rotated to cause the regulators to move towards each other and to contact the pipe ends, thereby precisely centering the pipes even where the pipes are not of strictly the same length.

Abstract: A heat exchanger includes a heat exchanger body and fasteners used to mount the body on an automobile or the like. The heat exchanger body comprises flat tubes and fin members alternatingly stacked on each other and a pair of hollow headers, with the ends of each tube being connected in fluid communication with the headers. Each fastener comprises a contacting concave portion with a shape which allows it to fit on an outer peripheral surface of a header, a hooking portion protruding from an end of the concave portion, and a fastening portion extending outwardly from another end of the concave portion. The concave portion is placed in close contact with the peripheral surface of the header, with a hook end of the hooking portion being inserted in between two adjacent tubes. The fasteners are soldered to the heat exchanger body and become integral with it.

Abstract: Apparatus for automatically forming pointed ends for raw metal pipes such as aluminum pipes subject to a drawing process, the pointed end of the pipes being of a reduced diameter convenient for the drawing process. A transporting device moves each raw pipe, which is in alignment with an axis of a pipe inlet of a swaging machine for producing the pointed ends, to a position below the inlet. Each pipe is raised by a lifting device to a height of the pipe inlet so as to be chucked by a gripping device which moves forward to insert a leading end of the pipe into the inlet. The lifting device and the raw pipe are kept out of contact with each other while the leading end is being processed to form the pointed end at the inserted end in the swaging machine whereby efficiency and productivity are improved for the process.

Abstract: A heat exchanger includes a core and a pair of headers, the core including flat tubes and corrugated fins sandwiched between the tubes, the headers having holes in which the end portions of the tubes are inserted, wherein each tube comprises a stop means for ensuring that an adequate length of the tubes become inserted in the headers.

Abstract: A consolidated duplex heat exchanger includes a first unit heat exchanger used for instance as a radiator, and a second unit heat exchanger employed for instance as a condenser for a car-cooler. The two unit heat exchangers are juxtaposed parallel with and close to each other, and united together by common corrugated fins each extending between cores of said unit heat exchangers. The corrugated fins are provided with cutouts intermediate the two unit heat exchangers parts so as to intercept undesirable heat conduction between said heat exchangers.

Abstract: A metallic pipe-cutting apparatus is constructed to cut elongate metallic pipes such as aluminum pipes into shorter pipes of a predetermined length, and comprises a main body, a chuck disposed rearwardly of the main body so as to hold trailing ends of the elongate metallic pipes, and a supporter disposed forwardly of the main body, with the main body interposed between the chuck and the supporter. The supporter comprises supporting pins which are to be inserted in leading ends of the pipes whose trailing ends are clamped by the chuck, so that the pipes clamped at their both ends are moved intermittently a predetermined distance so as to be successively cut into the predetermined length, with their outer peripheral surfaces not being scratched or flawed due to sliding contact with clampers or other members.

Abstract: A condenser apparatus includes a pair of headers provided in parallel with each other; a plurality of tubular elements whose opposite ends are connected to the headers; and fins provided in the air paths between one tube and the next. Each of the headers is made of a cylindrical pipe of aluminum. At least one of the headers is internally divided by a partition into at least two groups of coolant passageways, thus enabling the flow of coolant to make at least one U-turn in the header. The partition extends into the header through a slit in the header. Each of the tubular elements is made of a flat hollow tube of aluminum. The opposite ends of the tubular elements are inserted into slits produced in the headers so that they are liquid-tightly secured.

Abstract: A method for brazing aluminum components with a flux, wherein the flux and the aluminum components are heated together in a brazing furnace filled with a nonoxidizing gaseous medium, thereby fluxing and brazing the aluminum components at one time, or wherein the flux is previously pulverized and electrostatically deposited on the aluminum components, and the fluxed aluminum components is heated to a brazeable temperature in the furnace, thereby melting the braze metal and effecting the braze joints between the aluminum components.

Abstract: A heat exchanger having a core and headers, the core including a plurality of tubular elements having tanks at respective ends and corrugated fins sandwiched between one tubular element and the next, and the headers being provided at corners of the core to introduce a cooling medium and discharge it out of the core, wherein each header comprises a flat body portion and a cylindrical head portion produced eccentric of the body portion so that each header is disposed at the corner of the core without allowing any portion thereof to protrude beyond the outside line of the heat exchanger.

Abstract: A method of forming a heat exchanger includes brazing heat exchanger components with a flux of non-corrosive fluoride complexes. The components comprise an aluminum alloy having improved brazing characteristics and containing 0.3 to 0.8% Mg, 4.0 to 8.0% Zn, one or more of 0.05 to 0.30% Zr, 0.05 to 0.30% Mn, 0.05 to 0.30% of Cr, 0.05 to 0.30% of Cu, aluminum and unavoidable impurities.

Abstract: A condenser adapted for use in the car cooling system, the condenser comprising a pair of headers provided in parallel with each other; a plurality of tubular elements whose opposite ends are connected to the headers; fins provided in the air paths between one tube and the next; wherein each of the headers is made of a cylindrical pipe of aluminum; wherein each of the tubular elements is made of a flat hollow tube of aluminum by extrusion; and wherein the opposite ends of the tubular elements are inserted into slits produced in the headers so that they are liquid-tightly soldered therein.