Abstract: A punch rivet and a die for the production of a punch rivet connection are described. The punch rivet is characterized by special rivet foot and underhead geometries. In the region of the rivet foot, the shank outer face and shank inner face are connected by way of a small radially outer radius and a larger radially inner radius, which radii merge into one another tangentially. The angle that the common tangent encloses with a radial plane is in the range of 10°±20°. The die is preferably matched to the described punch rivet, but can also be used in combination with conventional punch rivets.

Abstract: A punch rivet and a die for the production of a punch rivet connection are described. The punch rivet is characterized by special rivet foot and underhead geometries. In the region of the rivet foot, the shank outer face and shank inner face are connected by way of a small radially outer radius and a larger radially inner radius, which radii merge into one another tangentially. The angle that the common tangent encloses with a radial plane is in the range of 10°±20°. The die is preferably matched to the described punch rivet, but can also be used in combination with conventional punch rivets.

Abstract: A punch rivet and a die for the production of a punch rivet connection are described. The punch rivet is characterized by special rivet foot and underhead geometries. In the region of the rivet foot, the shank outer face and shank inner face are connected by means of a small radially outer radius and a larger radially inner radius, which radii merge into one another tangentially. The angle that the common tangent encloses with a radial plane is in the range of 10°±20°. The die is preferably matched to the described punch rivet, but can also be used in combination with conventional punch rivets.

Abstract: The invention relates to a rivet (2) for connecting workpieces (11, 12), in particular a blind rivet, having a sleeve (1) with a shank (5) and a widened preformed head (13) adjoining thereto, and optionally a rivet mandrel (8) with a head (9), wherein an end of the shank (5) lying opposite the preformed head (13) if necessary can be deformed to form a driven head by drawing the rivet mandrel (8) into the sleeve (1). In order that during the placement of a rivet (2) a gap (10) between the rivet (2) and workpieces (11, 12) to be connected can be closed and a highly loadable connection can be achieved, at least one indentation (3) running axially and/or at least one slot running axially are provided in the shank (5), which indentation (3) or which slot (4) during the placement of the rivet (2) causes a radial expansion of the shank (5) of the sleeve (1) towards the workpieces (11, 12).

Abstract: The invention relates to a rivet for connecting parts, in particular aircraft components, through which holes are formed, the rivet including a sleeve part, which has a rivet head with an axially extending cavity and an adjoining or is composed of such rivet head and a rivet mandrel having an essentially cylindrical base body and a widened rivet mandrel head in relation to the diameter thereof and which passes through the sleeve part and along the cavity with its base body. So that a cost-effective connection with improved loadability can be produced between workpieces, even when they have holes of different sizes for the rivet, the rivet mandrel according to the invention has ribs running axially on the cylindrical base body.

Abstract: A punch rivet and a die for the production of a punch rivet connection are described. The punch rivet is characterized by special rivet foot and underhead geometries. In the region of the rivet foot, the shank outer face and shank inner face are connected by means of a small radially outer radius and a larger radially inner radius, which radii merge into one another tangentially. The angle that the common tangent encloses with a radial plane is in the range of 10°±20°. The die is preferably matched to the described punch rivet, but can also be used in combination with conventional punch rivets.

Abstract: The invention relates to a rivet (2) for connecting workpieces (11, 12), in particular a blind rivet, having a sleeve (1) with a shank (5) and a widened preformed head (13) adjoining thereto, and optionally a rivet mandrel (8) with a head (9), wherein an end of the shank (5) lying opposite the preformed head (13) if necessary can be deformed to form a driven head by drawing the rivet mandrel (8) into the sleeve (1). In order that during the placement of a rivet (2) a gap (10) between the rivet (2) and workpieces (11, 12) to be connected can be closed and a highly loadable connection can be achieved, at least one indentation (3) running axially and/or at least one slot running axially are provided in the shank (5), which indentation (3) or which slot (4) during the placement of the rivet (2) causes a radial expansion of the shank (5) of the sleeve (1) towards the workpieces (11, 12).

Abstract: The invention relates to a rivet for connecting parts, in particular aircraft components, penetrated by bores, comprising a sleeve part (1), which has a rivet head (11) with a cavity running axially and a shank adjoining the rivet head (11) or is composed of this rivet head (11), and a rivet mandrel (2), which has an essentially cylindrical base body (26) and a widened rivet mandrel head (21) with respect to the diameter (D) thereof and which penetrates the sleeve part (1) with its base body (26) along the cavity. So that a cost-effective connection with improved loadability can be produced between workpieces, even when they have bores of different sizes for the rivet, it is proposed according to the invention that the rivet mandrel (2) has ribs (22) running axially on the cylindrical base body (26).

Abstract: A rivet capable of self-piercing at least one sheet of material and becoming embedded in one of such sheets, generally consisting of a head section and a shank section formed integrally with the head section, wherein the head section includes an upwardly and outwardly curved side wall surface extending from the shank section to an upper portion of the head section, and the shank section includes a recess in a lower end thereof, with the lower end of the shank section having a peripheral cutting edge sufficient to penetrate such material.

Abstract: A rivet capable of self-piercing at least one sheet of material and becoming embedded in one of such sheets, generally consisting of a head section and a shank section formed integrally with the head section, wherein the head section includes an upwardly and outwardly curved side wall surface extending from the shank section to an upper portion of the head section, and the shank section includes a recess in a lower end thereof, with the lower end of the shank section having a peripheral cutting edge sufficient to penetrate such material.

Abstract: The self-penetrating fastening device proposed consists of a rivet (3), acted on by a punch (13), and a die (15), the rivet consisting of a head (4) and a shank (6) with a central cavity (8) whose open end partly penetrates a metal sheet (1) in which it is held. At the end of the rivet shank (6) remote from the rivet head (4), the cavity (8) is essentially conical in shape, the angle of the aperture being &agr;. In addition, the transition zone between the rivet shaft (6) and the underneath (11) of the rivet head (4) is essentially rounded (R1). A rivet joint produced using this device is sufficiently strong to meet severe requirements, and the surface of the metal sheet in the region of the rivet is not affected by the perforation process.

Abstract: A rivet capable of self-piercing at least one sheet of material and becoming embedded in one of such sheets, generally consisting of a head section and a shank section formed integrally with the head section, wherein the head section includes an upwardly and outwardly curved side wall surface extending from the shank section to an upper portion of the head section, and the shank section includes a recess in a lower end thereof, with the lower end of the shank section having a peripheral cutting edge sufficient to penetrate such material.

Abstract: A method of riveting comprises inserting a self-piercing rivet into sheet material without full penetration such that the deformed end of the rivet remains encapsulated by an upset annulus of the sheet material. The sheet material is clamped with a substantial force during the riveting operation in the region around the rivet insertion location. The clamping force is maintained constant throughout at least the major part of the riveting operation and has a magnitude of up to 1.5 tonnes. A riveting machine for carrying out the method comprises a punch, means for feeding rivets successively to the punch for insertion into sheet material to be riveted, a die aligned with the punch for deforming the rivet inserted thereby, and clamping means for clamping the sheet material with a substantial force during the riveting operation in the region around the rivet insertion location.

Abstract: A method of improving the reproducibility of the welds in an electric spot welding machine comprises prior to the initiation of a welding operation passing a preheating current of lower magnitude than the welding current through the parts to be welded. When either the total electrical workpiece resistance of the parts to be welded has fallen below a given limit or when its rate of decrease is slower than a predetermined limit the changeover from preheating current to welding current is effected.