Daimler Chrysler Ag

Mercedes-Benz Aktiengesellschaft

Daimler-Benz Ag

Pierre Bonny

Thomas Huelsberg

Thorsten Sternal

Thomas Hulsberg

Henning Blocker

Thoralf Nehls

Eckhard Reese

Gerd Tiefenbacher

Matthias Schroeder

Henning Bloecker

Helmut Augustin

Stefan Schwarz

Berndt Schutz

Holger Nuhn

Ralf Puenjer

Ralf Punjer

Thomas H&uuml;lsberg

Heinz-Ruediger Otte

Wolfgang Jekel

Hans-Jorg Kaifel

Hans-J&ouml;rg Kaifel

Norbert Kreutzig

A process and a device produces an assembly linkage on a hollow profile which is shaped for the installation of the assembly part by internal high-pressure remodeling. In order to achieve the shaping of an assembly linkage in a component space-saving, for a subsequent assembly correctly positioned, and with regard to its contour exactly fitted to the assembly part, in simple manner and even with high degrees of remodeling in a secure process, the hollow profile, under internal pressure, which is smaller than the remodeling pressure, is indented at the place of the to-be-produced assembly linkage by a die and by forming a rough contour. Afterward, while the die remains in this indenting position, a fluid high pressure is created in the hollow profile. Thereby, the hollow profile sides surrounding the die are molded to the external contour of the die, and that after releasing the fluid high pressure and the subsequent removal of the die, the finished trough-shaped assembly linkage is released.

Apparatus for producing an assembly linkage on a hollow profile

Process and apparatus for producing an assembly linkage on a hollow profile

A method and an apparatus are provided for internal high-pressure forming of a workpiece in a closed internal high-pressure forming die. The workpiece is expanded owing to the internal high fluid pressure exerted by a pressure generator and coming to rest on the cavity of the forming die. The workpiece and the forming die form friction partners in the areas of contact. In order to improve process reliability during the internal high-pressure forming of workpieces and to expand the scope of the method, vibration is imparted directly to at least one of the friction partners by a vibration generator during forming.

Internal high pressure forming method for a workpiece

A method for manufacturing an air-gap-insulated exhaust pipe having a branch stub, as well as an exhaust pipe produced according to such a method and a tool for forming such an exhaust pipe. Two tubes are inserted into one another to form a double tube. The double tube is placed in a first internal high-pressure shaping tool, and exposed to internal high pressure fluid such that it expands to match the contours of the engraving of the first shaping tool, and a double-walled branch stub is blown out of the double tube. The partially formed double tube is then placed in a second internal high-pressure shaping tool, with the double tube being surrounded, between the two ends including the branch stub, circumferentially and throughout by a corresponding design of the engraving, by an expansion chamber. The outer tube is expanded between the outer tube and inner tube under high pressure up to a precise fit with the engraving of the second shaping tool to form an insulating air gap, with the end of the branch stub being supported externally without yielding via a second counterpunch. The finished double tube is removed from the second shaping tool and a cap area of the branch stub, containing the end, is cut off to form a through opening between the interior of the inner tube and the ambient environment outside the air-gap-insulated exhaust pipe.

Air gap insulated exhaust pipe with branch pipe stub and method of manufacturing same

A process and a device produces a linkage of a hollow cylindrical air/fuel ratio detector holder to an opening for the impingement of the air/fuel ratio detector, which is fastened into the holder, to an exhaust pipe equipped with exhaust gas. A desired finished shape is given through internal high-pressure remodeling of a blank pipe. During this process, internal high-pressure remodeling creates a contact surface on the exhaust pipe which is formed by a buckling. The contact surface is created to in the inverted shape of the contact contour of the casing surface of the holder so that a dimensionally stable linkage of an air/fuel ratio detector holder to an exhaust pipe is achieved simply.

Process and apparatus for producing a linkage of an air/fuel ratio detector holder to an exhaust pipe

A built-up airgap-insulated exhaust manifold of an exhaust system of a motor vehicle includes at least two exhaust pipes with an inlet flange attached in each case to one end and to be fastened to the cylinder head of an internal combustion engine of a motor vehicle. The exhaust pipes include a pipe bend and at least one branched pipe piece connected to the latter. If a plurality of branched pipe pieces are arranged they are connected to one another in a row and the last pipe piece in the row forms a header connected at one end to the exhaust tract leading further on in the exhaust system. The exhaust manifold has at least one exhaust pipe, which is designed as a double pipe with airgap insulation between an outer and an inner pipe, and possessing at least one exhaust pipe without an air insulation gap. The outer pipe and the inner pipe of the airgap-insulated exhaust pipe bear against one another at the end which is plugged together with and welded to an associated inlet flange.

Built-up airgap-insulated exhaust manifold of a motor vehicle and method for producing it

A process for manufacturing an air-gap-insulated exhaust elbow of a motor vehicle exhaust system achieves in a simple manner a manufacturing of space-saving air-gap-insulating exhaust elbows which is reliable with respect to the process and can be precisely reproduced. The exhaust elbow is joined together from several air-gap-insulated exhaust pipes as well as the pertaining entry flanges and the exit flange, which, by way of an internal high-pressure metal forming process, are shaped in an air-gap-insulating manner from one double pipe respectively. The ends of the air-gap-insulated exhaust pipes which are to be connected with one another are first trimmed while opening the respective air insulating gap and are then fitted into one another. In such case, the ends are shaped such that the fitted connections of the outer pipes and of the inner pipes of the exhaust pipes to be connected are made with play. The mutually connected outer pipe ends of the exhaust pipes are welded together at the point of their fitted connection while forming a circular bead. The connection-free ends of the exhaust pipes to be connected to the cylinder head are fitted together with the respective pertaining entry flanges and are welded together and the connection-free end, which faces away from the cylinder head, of the last one of the branched exhaust pipes arranged in a row side-by-side, is fitted together with the exit flange and is welded to the latter.

Process of manufacturing an air-gap-insulating exhaust elbow of a vehicle exhaust system

An apparatus and method of attaching an exhaust manifold to an engine's cylinder head utilizing an oversized hole in the manifold, a stud fastener extending through the oversized hole, a spacer element around the stud fastener, and a nut adapted to be tightened to engage the spacer element and the flange wherein a flat gasket is compressed to a desired extent which is not so excessive that it inhibits sliding movement caused by thermal growth of the manifold.

Fastening an exhaust manifold to an engine cylinder head

A process and a device produces a linkage of a hollow cylindrical air/fuel ratio detector holder to an opening for the impingement of the air/fuel ratio detector, which is fastened into the holder, to an exhaust pipe equipped with exhaust gas. A desired finished shape is given through internal high-pressure remodeling of a blank pipe. During this process, internal high-pressure remodeling creates a contact surface on the exhaust pipe which is formed by a buckling. The contact surface is created in the inverted shape of the contact contour of the casing surface of the holder so that a dimensionally stable linkage of an air/fuel ratio detector holder to an exhaust pipe is achieved simply.

Process and apparatus for producing a linkage of an air/fuel ratio

A method for manufacturing an air-gap-insulated exhaust manifold, including exhaust-conducting inner tube sections and an outer shell divided into an upper shell and a lower shell, with the inner tube sections, of which at least one is designed as a curved tube, being plugged into one another. The inner tube sections plugged into one another are inserted as an assembled component into the lower shell, centered relative to the outer shell that is formed later, with the upper shell then being placed on the lower shell and pressed against the latter. Then the upper and lower shells and the inner tube sections are welded to the outer shell at those points at which they pass through the outer shell. In order in simple fashion always to ensure a sliding fit on the inner tube sections as well as the formation of a uniform air gap insulation of the inner tube sections following completion of the manufacture of the exhaust manifold, it is proposed to connect the inner tube sections with each other forcewise before they are inserted into the lower shell by means of a connecting element in each case made of a heat-volatile material, with the connecting elements being dissolved under the influence of heat following the welding of the upper and lower shells with the inner tube sections.

Method for manufacturing an air-gap-insulated exhaust manifold

An arrangement for the internal high-pressure forming of hollow profiles has an internal high-pressure forming tool, into whose die sinking the hollow profile can be inserted. At least one axial die has a sealing head which can be inserted with play by a section into the hollow profile. This sealing head has a support part which is provided with a pressure fluid duct and on which a sealing arrangement is held and which is rigidly connected with the axial die, and has a stop surface, which in the operative position of the sealing head rests on the face side against the end of the hollow profile. The sealing arrangement contains at least one sealing element which can be radially spread open for an allaround sealing contact on the interior side of the hollow profile. To achieve a reliable fluid high-pressure-tight sealing in a simple manner without deformation of the hollow profile, so that a forming is permitted which is secure with respect to the process relative to stable pressure conditions during internal high-pressure forming, the sealing arrangement has a supporting ring which supports the sealing element, can be axially displaceably guided on the support part relative thereto and dips into the hollow profile when the sealing head is coupled to the hollow profile. A stop body has the stop surface of the sealing ring on the hollow profile and which is fixedly connected with the supporting ring. The support part has an operating device which, when the stop body rests against the hollow profile, acts upon the sealing element in a spreading-open manner because of a further axial movement of the support part relative to the supporting ring in an interaction with the supporting ring.

Arrangement for the internal high-pressure forming of hollow profiles

An exhaust manifold for conducting exhaust gas from an internal combustion engine including a collection pipe structure having branches with engine flanges at their ends for mounting to cylinder outlet ports of the engine and an outlet flange at the downstream end of the pipe structure for connection to an exhaust pipe. The collection pipe structure has in the area of the branches a cross-section with different diameters for first and second cross-sectional directions which are normal to each other so as to form a drop-like or oval cross-sectional area which, in a downstream direction, continuously changes until the two diameters are equal providing for a circular shape at the end of the collection pipe structure adjacent the outlet flange.

Exhaust manifold for conducting exhaust gas out of an internal

In a pipe coupling between first and second pipe sections having end areas received within one another, one of the end areas has radial projections which are arranged circumferentially around its outer or inner circumference and extend toward the inner or outer surface of the other end area which has a smooth cylindrical surface adjacent the projections to permit sliding and some tilting of the pipe sections relative to each other.

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Hamburg, Germany

Pierre Bonny