wherein an object is pinched between a moving closing element of the closing device and a stop edge of the closing device during a closing operation having the following steps determining an indicator of the instantaneous closing force during a closing operation determining an indicator of a force of acceleration indicating a force of acceleration acting on the closing element of the closing device during a closing operation providing a closing force threshold value depending on the indicator of the force of acceleration detecting a pinch case if the determined indicator of the instantaneous closing force exceeds the closing force threshold value application_number US 201013382944 A description as an example of a closing device fig1 shows a window lifting system 1 for a motor vehicle in which a window pane 2 closing element can be moved up and down within a window frame 3 in a vehicle door 4 in order to close and to open the window the movement of the window pane 2 is undertaken by a servomotor 5 which is coupled to the window pane 2 via a suitable mechanism 6 for example the mechanism 6 can be designed in such a manner that the window pane.