Joining method and apparatus

Abstract

A joining apparatus includes a joining tool on which a joining component is held and which moves the joining component in an axial direction to position a metal section of the joining component on a surface of the workpiece. A heating device is provided for heating the metal section of the joining component to integrally couple the metal section to the workpiece. A sensor is connected to the joining tool acting to determine a zero point defined when a joining surface of the metal section has reached the surface of the workpiece before the workpiece is axially deformed.

What is claimed is: 
     
         1 . A joining apparatus, comprising:
 a joining tool having a joining head from which a carriage is axially displaceable, the carriage acting to hold a joining component and to move the joining component in an axial direction onto a surface of a workpiece;   the joining component including a metal section in the form of a flat metal element; and   a heating device connected to the carriage for heating the metal section of the joining component after the metal section contacts the workpiece.   
     
     
         2 . The joining apparatus of  claim 1 , wherein the heating device is an induction heating device having a coil and a ferrite core, the ferrite core having a sleeve section, and wherein the joining component is held in the carriage of the joining tool such that a holding section of the joining component is surrounded by the sleeve section. 
     
     
         3 . The joining apparatus of  claim 2 , wherein the sleeve section is connected to a vacuum holding device acting to exert a vacuum holding force on a holding section of the joining component. 
     
     
         4 . The joining apparatus of  claim 2 , wherein the joining tool includes a temperature sensor acting to measure a temperature of a joint zone. 
     
     
         5 . The joining apparatus of  claim 4 , wherein the temperature sensor is arranged on the sleeve section. 
     
     
         6 . The joining apparatus of  claim 2 , further including:
 a holding device acting to hold the joining component; and   a linear drive;   wherein both the heating device and the holding device are arranged on the carriage, the carriage moved by the linear drive with respect to a housing of the joining tool.   
     
     
         7 . The joining apparatus of  claim 6 , further including a position sensor connected to the housing acting to detect a position of the carriage. 
     
     
         8 . The joining apparatus of  claim 6 , further including a force sensor connected to the housing acting to detect a force with which the joining component is pressed onto the workpiece. 
     
     
         9 . The joining apparatus of  claim 6 , further including an orientation sensor connected to the housing acting to detect an orientation of the joining tool in space. 
     
     
         10 . The joining apparatus of  claim 1 , wherein the joining component includes a flange section having the metal section integrated in the flange section, the metal section together with a rim of the flange section forming a joining surface. 
     
     
         11 . The joining apparatus of  claim 1 , further including a sensor connected to the joining tool acting to determine a zero point defined when a joining surface of the metal section has reached the surface of the workpiece before the workpiece is axially deformed. 
     
     
         12 . A joining apparatus, comprising:
 a joining tool on which a joining component is held and which moves the joining component in an axial direction to position the metal section on a surface of a workpiece, the joining component having a holding section and a polymeric material flange section retaining a metal section, the metal section directed toward the workpiece; and   a heating device for heating the metal section of the joining component to integrally couple the metal section to the workpiece.   
     
     
         13 . The joining apparatus of  claim 12 , wherein the joining tool further includes a carriage adapted to releasably engage the holding section of the joining component. 
     
     
         14 . The joining apparatus of  claim 13 , wherein the carriage further includes a sleeve section, the joining component being held on the joining tool such that the holding section of the joining component is surrounded by the sleeve section. 
     
     
         15 . The joining apparatus of  claim 14 , further including multiple projections formed on an upper face of the flange section operating to ensure a distance is maintained between a lower face of the sleeve section and an upper face of the flange section to avoid adhesion of the sleeve section when the flange section is heated with the metal section. 
     
     
         16 . The joining apparatus of  claim 15 , wherein a length of the projections defines a magnetic field density in the metal section. 
     
     
         17 . The joining apparatus of  claim 12 , further including a sensor connected to the joining tool acting to determine a zero point defined when a joining surface of the metal section has reached the surface of the workpiece before the workpiece is axially deformed. 
     
     
         18 . A joining apparatus, comprising:
 a joining tool on which a joining component is held and which moves the joining component in an axial direction to position a metal section of the joining component on a surface of the workpiece;   a heating device for heating the metal section of the joining component to integrally couple the metal section to the workpiece; and   a sensor connected to the joining tool acting to determine a zero point defined when a joining surface of the metal section has reached the surface of the workpiece before the workpiece is axially deformed.   
     
     
         19 . The joining apparatus of  claim 18 , wherein the sensor is a distance sensor acting to measure a distance between the sensor and the zero point, before the workpiece is axially deformed by a force exerted from contact between the joining component and the workpiece. 
     
     
         20 . The joining apparatus of  claim 18 , wherein the sensor is a force sensor connected to the joining tool, and the zero point is determined by a change in a force when the joining component touches the workpiece. 
     
     
         21 . The joining apparatus of  claim 18 , wherein the zero point is determined during the lowering of the joining component to the surface of the workpiece to determine an axial position of the surface of the workpiece in an undeformed state, to thereby regulate a position of the joining component with respect to the zero-point surface of the workpiece. 
     
     
         22 . The joining apparatus of  claim 18 , wherein the joining component includes a holding section and a flange section retaining the metal section, the metal section directed toward the workpiece. 
     
     
         23 . The joining apparatus of  claim 18 , further including a store having an identification code provided in the joining tool, the identification code identifying the joining tool. 
     
     
         24 . The joining apparatus of  claim 18 , wherein the joining tool further includes a carriage adapted to releasably engage a holding section of the joining component. 
     
     
         25 . The joining apparatus of  claim 24 , further including a store provided on the carriage acting to identify a type of the heating device.