Method for the attachment of a functional element

#The invention relates to a method for the attachment, in particular for the liquid-tight and/or gas-tight attachment, of a functional element, in particular a fastener element, to a sheet metal part.

#The invention further relates to a die and a functional element which can be used in the method in accordance with the invention and to a component assembly which can be manufactured by the method in accordance with the invention.

#Functional elements such as nuts or bolts are attached to sheet metal parts in the manufacture of automobiles, for example, in order to allow the most varied components to be joined to the sheet metal parts.

#The invention is described below by way of embodiments with reference to the drawing. There are shown:

#FIG. 1 an embodiment of a functional element, partly sectioned in a longitudinal direction, which can be attached to a sheet metal part by means of the method in accordance with the invention;

#FIG. 2 the functional element of FIG. 1 and the sheet metal part after the attachment of the member to the sheet metal part;

#The attachment of a functional element to a sheet metal part is nowadays normally performed in the working of sheet metal by means of a press or of a robot by the cooperation of a setting head and a die, with the die being mounted, for example, in a lower tool of a press, while the setting head is attached to an upper press tool or to an intermediate plate of the press. Other attachment possibilities are also possible. The die can, for example, be attached to the intermediate plate of the press and the setting head to the upper tool of the press. Reversed arrangements are also feasible where the die is attached to the upper tool and the setting head to the lower tool of the press or to the intermediate plate. It is, in addition, not absolutely necessary for the die and the setting head to be in a press; they could, for example, be moved towards and away from one another by a robot, or represent parts of a different kind of tool.

#The respectively used setting head, or the tool associated with it, has, in a manner known per se, a frequently tubular hold down member which clamps the sheet metal part against the stationary end face of the die or against the upper side of the tool receiving the relevant die in each case. A particularly preferred embodiment of the functional element in accordance with the invention and of the die and of the method to insert this element will now be described with reference to FIGS. 1 to 6.

#FIG. 1 shows first of all a functional element 210, here in the form of a bolt element, with a shaft part 210b having a thread 211 and with a hollow head part 210a having at least substantially the same outer diameter as the shaft part 210b. It is pointed out that the shaft part 210b does not necessarily have to be executed with a thread 211, but can, as previously, have a design deviating from this which can be selected as desired to achieve the respectively intended function. The shaft part 210b can, for example, be made as a smooth guide spigot or as a carpet fastening pin with an annular groove allowing a snap connection to a carpet eyelet. It is particularly favourable with this element for, among other possibilities, the shaft part 210b and the head part 210a to have at least substantially the same outer diameters so that the functional element can be made at a favourable cost from bar stock or wire material or from a tubular section.