| 摘要 |
A telescopic unit for a windscreen wiper device consists of a U-shaped inner rail (1), a U-shaped outer rail (3), and at least one support row of loaded balls (9) which roll between a groove-type inner raceway (8) of each of the two inner limbs (2) of the inner rail (1) and a groove-type outer raceway (7) of the opposite outer limb (6) of the outer rail (3). In order that the telescopic unit has a relatively large space between the inner rail (1) and the outer rail (3) despite a compact construction and, additionally, loss of lubricant during operation is avoided, each support row is closed at its two ends by an exclusive return row of non-loaded balls (10) to form an endless row of balls. This row of balls is incorporated in a guide channel (11) of a cage (12) which is firmly connected to the inner or outer rail (1, 3). The balls (10) of the return row run on a return track (13) of the inner or outer rail (1, 3) connected to the cage (12) and are tightly covered by the guide channel (11). The balls (9) of the support row are arranged in a continuous guide slot (14) of the cage (12). The cage (12) bears sealing means (15) which completely surround the edge of the guide slot (14) from the outside. <IMAGE> |
