Abstract: A method for manufacturing a fuel inlet having a good sealing property and a screw structure formed in a precise position involves expanding one end of a long-length stainless pipe (metal pipe) using a cored bar, the tip of the expanded portion which becomes non-uniform as a result of the expanding step is cut off, a screw structure is formed in the expanded portion by using a punch, the tip of the expanded portion which becomes non-uniform as a result of the screw structure forming step is cut off, and thereafter curl forming is conducted to the end of the expanded portion which becomes uniform by using a die so as to provide a seal portion.

Abstract: A metal pipe 11 of a smaller diameter engages a metal pipe 13 of a larger diameter to provide a double-pipe structure in a predetermined area in the longitudinal direction, wherein the diameter of the two pipes 11 and 13 of the double-pipe structure section is integrally expanded using a pipe expansion technique. By making a predetermined section of the pipe member a double-pipe structure, it is possible to provide the strength and rigidity necessary for each section. It is also possible to join the two pipes by expanding the diameter of each pipe at the double-pipe structure section. By forming a section where high strength is not required by a pipe of a smaller diameter, it is possible to lighten the pipe member. Materials for the pipes 11 and 13 are carbon steels for machine structural use. If aluminum is used for the metal pipe 11 of a smaller diameter, it is possible to further lighten the pipe member.

Abstract: A method for manufacturing a fuel inlet having a good sealing property and a screw structure formed in a precise position involves expanding one end of a long-length stainless pipe (metal pipe) using a cored bar, the tip of the expanded portion which becomes non-uniform as a result of the expanding step is cut off, a screw structure is formed in the expanded portion by using a punch, the tip of the expanded portion which becomes non-uniform as a result of the screw structure forming step is cut off, and thereafter curl forming is conducted to the end of the expanded portion which becomes uniform by using a die so as to provide a seal portion.

Abstract: In manufacturing a fuel inlet, bulge forming and bend processing are conducted to a stainless pipe which will serve as an inlet pipe. Next, one end of the stainless pipe is eccentrically expanded, and the hardened portion is removed. After the pipe expanding step is finished, boring processing is conducted so that a breather pipe can be inserted into the inlet pipe, a guide is spot-welded to the inside of the eccentrically expanded portion, and a screw structure is formed. The inlet pipe and the breather pipe are degreased and cleaned as a pretreatment for brazing, and brazing is conducted by using BAg-4 (Low-temperature brazing material) at a temperature of 750-850° C. Removing of the flux and cleaning are conducted as a post-treatment for brazing, and finally coating is conducted.

Abstract: In order to manufacture a fuel inlet, bulge forming and bend processing are conducted to a stainless pipe which will serve as an inlet pipe. Next, one end of the stainless pipe is eccentrically expanded, and the hardened portion is removed. After the pipe expanding step is finished, boring processing is conducted so that a breather pipe can be inserted into the inlet pipe, a guide is spot-welded to the inside of the eccentrically expanded portion, and a screw structure is formed. The inlet pipe and the breather pipe are degreased and cleaned as a pretreatment for brazing, and brazing is conducted by using BAg-4 (Low-temperature brazing material) at a temperature of 750-850° C. Removing of the flux and cleaning are conducted as a post-treatment for brazing, and finally coating is conducted.

Abstract: A fuel feed pipe 1 having a branch pipe 6 for releasing evaporated fuel to a canister is provided, wherein the fuel feed pipe 1 is provided with a branch pipe blocking mechanism 8 for blocking an opening of the branch pipe 6 by being mechanically linked with the motion of inserting a fuel feed gun G. The branch pipe blocking mechanism 8 consists of a leaf spring 9 made of stainless steel and a rubber seal 10. A base end section of the leaf spring 9 is secured to a fuel feed guide 3 and a top side of the leaf spring 9 is provided with the rubber seal 10. When a shutter valve 4 is rotated by the insertion of the fuel feed gun G, the leaf spring 9 is elastically deformed by being mechanically linked with the rotation of the shutter valve 4 to allow the rubber seal 10 to close the opening of the branch pipe 6.

Abstract: A metal pipe 11 of a smaller diameter engages a metal pipe 13 of a larger diameter to provide a double-pipe structure in a predetermined area in the longitudinal direction, wherein the diameter of the two pipes 11 and 13 of the double-pipe structure section is integrally expanded using a pipe expansion technique. By making a predetermined section of the pipe member a double-pipe structure, it is possible to provide the strength and rigidity necessary for each section. It is also possible to join the two pipes by expanding the diameter of each pipe at the double-pipe structure section. By forming a section where high strength is not required by a pipe of a smaller diameter, it is possible to lighten the pipe member. Materials for the pipes 11 and 13 are carbon steels for machine structural use. If aluminum is used for the metal pipe 11 of a smaller diameter, it is possible to further lighten the pipe member.

Abstract: A fuel feed pipe 1 having a branch pipe 6 for releasing evaporated fuel to a canister is provided, wherein the fuel feed pipe 1 is provided with a branch pipe blocking mechanism 8 for blocking an opening of the branch pipe 6 by being mechanically linked with the motion of inserting a fuel feed gun G. The branch pipe blocking mechanism 8 consists of a leaf spring 9 made of stainless steel and a rubber seal 10. A base end section of the leaf spring 9 is secured to a fuel feed guide 3 and a top side of the leaf spring 9 is provided with the rubber seal 10. When a shutter valve 4 is rotated by the insertion of the fuel feed gun G, the leaf spring 9 is elastically deformed by being mechanically linked with the rotation of the shutter valve 4 to allow the rubber seal 10 to close the opening of the branch pipe 6.

Abstract: A fuel supplying assembly comprising a cap and a metal pipe having double screw threads thereon. The cap comprising a handle, an insertion portion and an idling mechanism that permits the handle to run idle with respect to the insertion portion when a predetermined force is applied.

Abstract: In an apparatus and a method for forming threaded portions around a metal pipe with accuracy and ease, a preliminary forming is performed so as to recess portions of the metal pipe a little bit inwardly in the radial direction thereof by advancing auxiliary forming punches while keeping main forming punches as they are. Thereafter, by receding the auxiliary forming punches back, while advancing the main forming punches, simultaneously, the threaded portions are formed on outer periphery of the metal pipe 3 shifted by 180° in phase thereof.

Abstract: In an apparatus and a method for forming threaded portions around a metal pipe with accuracy and ease, a preliminary forming is performed so as to recess portions of the metal pipe a little bit inwardly in the radial direction thereof by advancing auxiliary forming punches while keeping main forming punches as they are. Thereafter, by receding the auxiliary forming punches back, while advancing the main forming punches, simultaneously, the threaded portions are formed on outer periphery of the metal pipe 3 shifted by 180° in phase thereof.