Hydrokinetic coupling apparatus, notably for motor vehicles

Hydrokinetic coupling apparatus, having a housing (12) capable of being rotatably locked to a driving shaft, a turbine wheel (14) capable of being rotatably locked to a driven shaft and a locking clutch (10) acting between the housing (12), having a wall (28) which is transverse overall and which carries centrally a tubular nose (17), and at its outer periphery an axially oriented annular (19), and the turbine wheel (14), the clutch including a piston (2) mounted so as to be axially mobile with respect to the turbine wheel (14) whilst being rotatably locked to the latter, and a counter-piston (3) associated with the housing (12), in which the piston (2) is interposed axially between the turbine wheel (14) and a mass (3), forming the counter-piston, rotatably mounted on the housing (12), and coupled elastically to the housing (12), and in which the mass (3) is pivotally mounted on the tubular nose (17), fixed to the housing (12), and forms the output element of a torsion damping device (4) including elastic means (7) with circumferential action and an input element consisting of the housing (12), characterized in that a bearing (41) is interposed radially between the inner periphery of the mass (3) and the outer periphery of the nose (17), in that the mass (3) has a main part (30) and, at the outer periphery of its main part (30), a transversely oriented annular projection (31) directed radially in the direction of the annular rim (19) on the housing, being offset axially with respect to the main part (30) of the mass (3) in the direction of the outer periphery of the turbine wheel (14), in that the projection (31) offers a contact surface (32) for the piston (2) and in that the circumferential-action elastic means (7) of the torsion damping device are mounted at the outer periphery of the main part (30) of the mass (3) between the transverse projection (31) on the mass (3) and the transverse part (28) of the housing (12).