Patent ID: 7581617

Claim:
A method for selectively providing a coupling between a first mechanical device and a second mechanical device, comprising: providing an electromechanical coupling unit having at least two coupling windings, wherein the coupling unit is configured to provide selective coupling between the first and second mechanical devices, and wherein each of the coupling windings is configured to be supplied with electrical energy by at least one connected electrical control unit; actuating the coupling unit to be closed if none of the two coupling windings are supplied with electrical energy, whereby the coupling unit provides a coupling between the first and second mechanical devices; and actuating the coupling unit to be open if at least one of the two coupling windings is supplied with electrical energy, whereby the coupling unit provides no coupling between the first and second mechanical devices; wherein: at least one electrical control unit is respectively assigned to each of the first and second mechanical devices, wherein each electrical control unit selectively supplies, using at least one trigger element, the respective connected coupling winding with electrical energy, as a function of state of the respective connected coupling winding, each connected electrical control unit has a respective assigned power supply, the electrical control units connected to the coupling windings are each assigned to one of the two mechanical devices, the electrical control units detect, with the aid of sensors, the functioning of the coupling unit, and a functional test of the coupling windings is implemented, and each individual coupling winding is cut off from supply of electrical energy for a brief predetermined period and the coupling unit remains open during the functional test.