Cam follower in a valve train of an internal combustion engine switchable between different lifts for at least one gas-exchange valve
US6273041A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 5, 2000 |
| Grant date | Aug 14, 2001 |
| Priority date | — |
| Expiry date | Sep 5, 2020 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF01L2307/00
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A cam follower (1) designed to be switchable between different lifts for at least one gas-exchange valve and includes two adjacent sections (2,4) which can be coupled together via a coupling element (15). The coupling element (15) cooperates with a shutoff slide (14). It is a special feature of the shut-off slide (14) that it is produced as a mechanically closable and openable piston for an inlet (22) in a pressure chamber (20) in front of the coupling means (15), the piston, however, being maintainable hydraulically in its open position via high switching pressure. At the same time, the shutoff slide (14) is completely incorporated in the cam follower (1) and does not extend beyond it. As a result, undesired fluctuations in the pressure of the hydraulic fluid can no longer act on the coupling means (15) during the base circle of the cams acting on the cam follower (1) and an intended turned-off state. At the same time, displacement of these coupling means (15) in their coupling direction is only possible if a sufficiently high pressure of the hydraulic fluid is available for such movement. Otherwise, the shutoff means (14), via the force of a pressing means (10), will close the in…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.