Patent ID: 7980365

Claim:
A brake mechanism for a utility vehicle, comprising: a non rotatable fixed body, a rotatable body rotatable relative to the fixed body, at least one brake disc which is non-rotatable relative to the fixed body, at least one rotating brake disc which is fixed for rotation with the rotatable body, a stop surface on the fixed body, a first annular hydraulic piston extending from a first annular hydraulic actuating chamber in a first side of the fixed body in a first axial direction and which, when the first annular chamber is pressurised, presses the fixed brake disc and the rotating brake disc against each other and against the stop surface to apply the brake, a spring mechanism which exerts an immobilising force on the first annular actuating piston member via circumferentially spaced intermediate pistons to press the fixed brake disc and the rotating brake disc against each other to apply the brake, and a second annular hydraulic piston extending from a second annular hydraulic actuating chamber in a second side of the fixed body in a second axial direction opposite to the first axial direction and interposed between the spring means and the intermediate pistons, the second annular piston, when the second annular chamber is pressurised, exerting a brake release force which counteracts the immobilising force of the spring mechanism so that the first piston no longer presses the fixed brake disc and the rotating brake disc against each other via the intermediate pistons.