Device for activating a wheel brake of a vehicle, and method for activating the wheel brake

A method for activating a combined wheel brake comprising a service brake and a parking brake, comprising a tensioning installation which has a spindle drive, having:

• a first electric motor which, for activating the tensioning installation, by way of a first gear mechanism is bi-directionally coupled to the spindle drive, and
• a second electric motor which, for likewise activating the tensioning installation, is coupled to the spindle drive,
• wherein the second electric motor, by way a self-locking second gear mechanism and a releasable coupling that acts in the activating direction, is coupled to the spindle drive, and
• wherein for service braking at least the first electric motor is activated, and for parking braking at least the second electric motor is activated, the first gear mechanism in the case of a non-energized first electric motor being entrained in a rotating manner by way of the closed coupling, and the first electric motor and the second electric motor being de-energized when the required tensioning force is reached.

A device for activating a wheel brake of a vehicle, comprising a tensioning installation which has a spindle drive, having:

• a first electric motor which, for activating the tensioning installation, by way of a first gear mechanism is bi-directionally coupled to the spindle drive, and
• a second electric motor which, for likewise activating the tensioning installation, is coupled to the spindle drive,
• wherein the second electric motor, by way a self-locking second gear mechanism and a releasable coupling that acts in the activating direction, is coupled to the spindle drive, and
• an output element of the second gear mechanism is disposed coaxially with an output shaft of the first gear mechanism, and spaced apart radially from the output shaft of the first gear mechanism.