Device for changing the control timing of the gas exchange valves of an internal combustion engine, in particular a hydraulic camshaft adjustment device of the rotary piston type

US6427654B2 · kind B2 · utility

Assignee

• INA Wälzlager Schaeffler oHG · DE

Inventors

• Hermann Golbach · Erlangen, DE
• Martin Steigerwald · Herzogenaurach, DE
• Jens Schafer · Herzogenaurach, DE
• Matthias Kapp · Oak Park, US
• Joachim Dietz · Frensdorf, DE

Key dates

• Filing date: Dec 22, 2000
• Grant date: Aug 6, 2002
• Expiry date: Dec 22, 2020

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T74/2102
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A hydraulic camshaft-adjusting device of the rotary piston type that includes of a drive gear (2) directly connected to a crankshaft and an impeller that is directly connected to a camshaft (3). The drive gear (2) has a cavity formed from a perimeter wall (5) and two side walls (5, 6) inside of which at least one hydraulic working chamber is formed from at least two boundary walls. The impeller has at least one radial vane (12) and each vane (12) divides one hydraulic work chamber into two hydraulic pressure chambers. The outer end (18) of each vane (12) of the impeller is pressed radially against the perimeter wall (5) of the drive gear (2) as a result of the force of a spring element (17) located at the inner end (15) of the vane. The spring elements (17) located at the inner end (15) of the vanes (12) have, at unchanged space requirements, a spring force that is greater than the pressure force of the hydraulic pressure medium acting on the outer end (18) of the vanes (12) in the respective actuated pressure chamber of the device (1).