Patent ID: 7014028

Claim:
A drive device comprising: at least one first switchgear ( 9 ) and one second switchgear ( 11 ) in which each switchgear is actuatable by a spring force in an engaged direction and by hydraulic pressure in a disengaged direction; wherein during simultaneous actuation of said first switchgear ( 9 ) and second switchgear ( 11 ) in the engaged direction, an output ( 7 ) of the drive device is prevented from rotating so as to form a parking brake, and a disengaging device ( 26 ) simultaneously disengaging said first switchgear ( 9 ) and said second switchgear ( 11 ), for simultaneously disengaging said first switchgear ( 9 ) and said second switchgear ( 11 ), said disengaging device ( 26 ) has a disengaging device piston ( 25 ) which is separately pressurizable from the first and second switchgears ( 9 , 11 ) and which, in a pressurized state, actuates both the first and second switchgear ( 9 , 11 ) in the disengaging direction against the spring force acting on the first and second switchgears ( 9 , 11 ); and the first switchgear ( 9 ) has a first switchgear piston ( 15 ) where power transmission elements ( 31 ) are situated by which movements of the disengaging device piston ( 25 ) of the disengaging device ( 26 ) can be transmitted to a second switchgear piston ( 21 ) of the second switchgear ( 11 ).