| 摘要 |
The invention concerns a needle sleeve (1), in particular for pivotably mounting the throttle valve shaft of a control device for recirculating exhaust gas in internal combustion engines, which consists primarily of a thin-walled outer ring (2) formed by non-cutting means and a needle roller and cage assembly (3) that is inserted in this outer ring (2) and is composed of a plurality of bearing needles (4) and a needle cage (5) that carries the bearing needles (4) at uniform spacings in the circumferential direction. The needle sleeve (1) has, at its axial sides, two radially inward facing ribs (6, 7) holding the needle roller and cage assembly (3) in the outer ring (2), and is designed with multiple seals (8, 9) by means of which the sleeve is sealed to prevent exhaust gas condensates from flowing through. According to the invention, the outer ring (2) of the needle sleeve (1) is designed as a rimless, cylindrical sleeve, while the seals (8, 9) of the needle sleeve (1) are composed of two lip sealing rings with an S-shaped cross-sectional profile that are located at least partially outside the outer ring (2) and are pressed onto its axial edges (10, 11), which sealing rings are at the same time implemented as radially inward facing ribs (6, 7) of the needle sleeve (1) that retain the needle roller and cage assembly (3) in the outer ring (2), and by means of which sealing rings the needle sleeve (1) can be sealed both statically to a housing enclosing it and dynamically to prevent exhaust gas condensates from flowing through. |
