Functional element for the attachment to a sheet metal part, component assembly manufactured from these and also a method for the attachment of the functional element to a sheet metal part

Abstract

A functional element ( 10 ), for fixing to a piece of sheet metal ( 40 ), such as for example, a nut element or a bolt element with a body section or head section, comprising an annular flange ( 14 ) which transforms into a cylindrical rivet section, is characterized in that the transformation from annular flange into the rivet section is formed by an at least essentially conical surface, forming a contact surface for a corresponding conical region of a piece of sheet metal, which, on fixing the functional element to a piece of sheet metal, is clamped between the side of the annular flange facing the rivet section and an annular bead ( 50 ) formed from the rivet section. An assembled component and a method for the fixing of a functional element are also disclosed.

1 . Method for the attachment of a functional element in accordance with  claim 1  to a sheet metal part for the manufacture of a component assembly, characterized in that a conical recess ( 42 ) is manufactured in a sheet metal part ( 40 ), with the cone angle (a) of the conical recess corresponding at least substantially to the cone angle (a) of the conical surface ( 16 ) of the functional element ( 10 ), with a hole ( 44 ) being provided in and concentric to the conical recess ( 42 ), with the diameter of the hole corresponding at least substantially to the diameter of the rivet section ( 20 ) of the functional element or being somewhat larger than this; in that the rivet section ( 20 ) of the functional element ( 10 ) is passed through the hole ( 44 ) of the conical recess ( 42 ) of the sheet metal part so that the conical region of the conical recess ( 42 ) enters approximately into contact with the conical surface ( 16 ) of the functional element the ring flange ( 14 ) enters into engagement with the sheet metal part ( 40 ) and in that a ring bead ( 50 ) is formed from material of section ( 20 ) which clampingly receives the conical region of metal part between itself and the ring flange ( 14 ).  
     
     
         2 . Method in accordance with  claim 1 , characterized in that the formation of the ring bead ( 50 ) takes place by displacement of a region of the rivet section ( 20 ) of a functional element ( 10 ) and in that the sheet material of the sheet metal part ( 40 ) is supported during this displacement in a die which brings the sheet metal material in the conical region into engagement with features of the functional element providing security against rotation.  
     
     
         3 . Method in accordance with  claim 1 , characterized in that the ring bead ( 150 ) is formed by turning over the rivet section ( 120 ) and in that during or after the turning over the sheet metal is supported in a die which brings the sheet material and the conical region ( 140 ) into engagement with features of the functional element providing security against rotation.  
     
     
         4 . Method in accordance with  claim 1 , characterized in that for the formation of the conical recess in the sheet metal part the sheet metal part which is supported on a die is pierced by the free end of the cylindrical section ( 20 ) of the element and formed into the conical recess in a correspondingly shaped recess of the die.  
     
     
         5 . Method in accordance with  claim 4 , characterized in that the piercing slug which arises during piercing of the sheet metal part is pressed by the cylinder section of the functional element into a passage of the die and is disposed off via this passage, i.e. in that the functional element itself forms a hole punch.  
     
     
         6 . Method in accordance with  claim 4 , characterized in that instead of forming a ring bead from the material of the rivet section the material from raised noses providing security against rotation and provided in raised form on the cylinder section of the functional element leads, by displacement of the material in the axial direction of the cylinder section towards the body portion of the functional element, which is brought about by the die that is used, to radial projections which are present at the positions of the noses providing security against rotation, which contact the rim zone of the opening of the conical formation of the sheet metal part and which preferably engage in form-locked manner into this conical formation.