| 摘要 |
<p>Friction braking device (10; 100; 200) comprising a drive shaft (12; 112; 212), a friction braking element (16, 20; 116; 216), and members (22; 142, 150; 242, 250) for transmission of the movement between the shaft (12; 112; 212) and the braking element (16, 20; 116; 216), able to move the braking element (16, 20; 116; 216) axially with 5 respect to the shaft (12; 112; 212) between a first brake-engaged condition, where the braking element (16, 20; 116; 216) is locked by the contact with an engaging surface (18), and a second brake-disengaged position, where the braking element (16, 20; 116; 216) is separated from the engaging surface (18) and is able to rotate driven by the shaft (12; 112; 212). The device is characterized in that the transmission members (22; 142, 150; 242, 10 250) comprise non-permanent coupling means (42, 50; 142, 150; 242, 250, 298, 299) which can be operated so as to engage and disengage the shaft (12; 112; 212) and the braking element (16, 20; 116; 216) with a relative movement of these latter two parts.</p> |
