Abstract: A cornerplate-less duct includes plate members joined to each other at side end portions by a seam joint to form a tubular duct having a rectangular cross-section. Two end portions of a plate are bent perpendicular to a longitudinal direction of the plate to form flange forming portions. Corner forming portions protrude from side ends of the flange forming portions in a width direction to form corner portions at the end portions of the duct. In an expanded shape of the plate, a cut portion is provided close to a longitudinal center of the plate member such that the cut portion extends in a width direction of the plate member and has a depth substantially equal to an overlapping portion of the corner forming portion.

Abstract: This invention is aimed at providing a cornerplate-less duct having a rational construction, which can significantly reduce the number of parts by effectively utilizing scraps conventionally discarded. Plate members are joined to each other at side end portions by a seam joint structure to form a tubular duct 10 having a rectangular cross-section. A starting end portion and a terminal end portion of a plate are bent in a direction substantially perpendicular to a longitudinal direction Za of the plate to form flange forming portions 3 integral with the plate. Corner forming portions 4 are formed integrally to protrude from side ends of the flange forming portions in a width direction to form corner portions at the starting and terminal end portions of the duct.

Abstract: An objective of the present invention is to provide a joint structure of a duct that can be formed easily and comprising features of the joint structure of a novel duct previously filed by the present applicant. A tip end portion of one of two plate members is bent to form an angle of 90 degrees or more, a U-shaped groove is formed at an tip end portion of the other plate member such that at least an opening portion of the groove is adapted to a bending angle of the one plate member so as to accommodate the bent tip end portion of the one plate member in an end portion of the other plate member, and the guide rail is formed by protruding at least a portion on a bottom side of the U-shaped groove of the other plate member obliquely from an outer face located on a base end side of a portion where the U-shaped groove is formed and constituting one of the wall faces of the duct.

Abstract: A hanger comprises a contact portion that makes surface contact with one face of the duct; a tongue piece as an engagement member that protrudes from the contact portion toward a tip end; a base portion bent continuously with the contact portion and away from the duct so as to form a guide rail accommodating space between the base portion and the tongue piece; a pressing portion formed continuously with the base portion, for pressing a face adjacent to the one face toward the tip end of the tongue piece to allow the guide rail to be securely retained between the pressing portion and the tongue piece; and a member for mounting a hanging member to the base portion. A method for hanging the duct comprises inserting a tongue piece of the hanger into the groove-shaped space of the duct; and bending the pressing portion toward the guide rail to press the face adjacent to the one peripheral face of the duct, thereby fixing the hanger to the duct.

Abstract: A duct joint structure for assembling a duct used for air conditioning or venting equipment, an assembly tool for assembling the joint portion, an assembly method of a duct, and a hanger for the duct with the duct joint structure. A duct joint structure includes at least two duct plate members arranged substantially at right angles in a sectional view. An end of a first plate member is bent substantially in accordance with the orthogonal relation, and the second plate member is formed at the forward end thereof with a U-shaped groove to accommodate the bent portion of the first plate member. A guide rail is protruded at not less than 90 degrees with respect to the outer surface of the second plate member from the side thereof spaced from the U-shaped groove.

Abstract: A duct joint structure for assembling a duct used for air conditioning or venting equipment, an assembly tool for assembling the joint portion, an assembly method of a duct, and a hanger for the duct with the duct joint structure. A duct joint structure includes at least two duct plate members arranged substantially at right angles in a sectional view. An end of a first plate member is bent substantially in accordance with the orthogonal relation, and the second plate member is formed at the forward end thereof with a U-shaped groove to accommodate the bent portion of the first plate member. A guide rail is protruded at not less than 90 degrees with respect to the outer surface of the second plate member from the side thereof spaced from the U-shaped groove.