| 摘要 |
<p>FRICTION BRAKE The present invention relates to an improved brake for a wheel which has a hub and is mounted for rotation about a central axis on an axle spindle. The brake is of the type which includes a housing rigidly extending from the spindle to encircle the hub for sealed engagement therewith to define a sealed annular chamber about the hub and the spindle. A pair of disc units are coaxially aligned with the axis and aligned with each other and mounted within the chamber for movement along the axis. A first disc unit of the pair is non-rotatable and mounted relative to the housing. A second disc unit of the pair is rotatable and mounted relative to the hub. The improvement is comprised of an annular hydraulic cylinder extending into the chamber in general alignment with the pair of disc units and including a pair of cylindrical surfaces which are coaxially aligned with the axis and have different diameters. An annular piston is provided having a pair of curved surfaces which are respectively aligned with the cylinder surfaces of the cylinder to include a portion thereon which makes sliding sealed engagement with its respective cylinder surface. A unit is provided for selectively supplying hydraulic fluid to and removing it from an area between the piston and the cylinder for selective movement of the piston toward a wall of the housing to frictionally engage the pair of disc means therebetween. Each of such curved surfaces of the piston extends at opposite sides of the portion of curved surface away from its respective cylindrical surface to provide clearance therebetween to allow some angular displacement of the piston relative to the axis without binding contact between the piston and the cylinder.</p> |
