| 摘要 |
A mechanical drive box (8) comprising at least a shaft (1; 3) and at least a drive member (10) on the shaft and for the transmission of the motion between the shaft and the drive member, a device for the transmission of motion comprising: a set of pawls (26) radially movable within seats (16) formed in the shaft (1), said pawls having internal and external ends (26A) shaped in radial and/or axial direction; inside said drive member, a housing (20) wherein a drive member is received having a shaped surface for cooperating with the external ends of said pawls; inside the shaft, an axial cavity (14) for housing a shaped core (30) axially movable for the operation, with elastic means (36) for reacting to the axial movement of said core; and on said core, shapings and inclined surfaces (40, 42) able to cooperate with the internal shaped ends of the pawls; the axial position of said core and/or the force of the elastic means acting on the core determine the radial position of said pawls and/or their resistance against a centripetal movement thereof. |
