Patent ID: 7160218

Claim:
A starter unit for a driven arrangement, the starter unit comprising: a rotation input to the starter unit and a rotation output from the starter unit; a hydrodynamic coupling, the hydrodynamic coupling including first and second rotatable fluid coupling elements; a drive element coupled in a rotationally fixed manner to the input, a separate driven element, drivable by the drive element and which is coupled to the output, wherein: the first and second rotatable fluid coupling elements are respectively a primary wheel of the hydrodynamic coupling connected to the drive element and a secondary wheel of the hydrodynamic coupling connected to the driven element, the primary wheel and the secondary wheel being the sole mechanism for coupling torque between the drive element and the driven element; and the wheels of the hydrodynamic coupling define a toroidal working area with a cross section in the form of two full circles, and which is at least partially fillable to a varying extent for varying torque between the primary and the secondary wheels; a free wheel mechanism between the driven element and the output; a selectively lockable bypass clutch arranged between the input and the output, wherein: the bypass clutch is connected in parallel with the hydrodynamic coupling between the input and the output; the clutch is operable to lock the input to the output and to release the locking of the input and the output; and the clutch is selectively lockable and releaseable independently of the filling and emptying of the toroidal working area; and a device providing fixed support of and braking of the secondary wheel.