Switchable tappet

US8161929B2 · kind B2 · utility

Assignee

• Schaeffler KG · DE

Inventors

• Mario Kuhl · Herzogenaurach, DE
• Lothar von Schimonsky · Gerhardshofen, DE
• Norbert Nitz · Erlangen, DE
• Lucia Hinkovska · Herzogenaurach, DE
• Sandra Schäfer · Annaberg-Buchholz, DE

Key dates

• Filing date: Nov 19, 2008
• Grant date: Apr 24, 2012
• Expiry date: Jan 19, 2030

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F01L2307/00
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

The invention proposes a switchable tappet (1) of a valve train of an internal combustion engine, said tappet comprising a hollow cylindrical housing (3) comprising a bottom (2), an inner element (5) being guided for relative axial displacement in a bore (4) of the housing (3), an at least indirect support for a gas exchange valve extending on a cam-distal front end (6) of the inner element (5), two diametrically opposing pistons as coupling elements (8) being arranged in a radial bore (7) of the inner element (5), which coupling elements (8), for effecting coupling [full valve lift], can be displaced partly beyond a parting surface (9) between the housing (3) and the inner element (5) into an entraining surface (12) of the housing (3) by the force of a compression spring (10a) clamped between inner front ends (10) of the coupling elements (8), wherein the entraining surface (12) is an direct constituent of a separate annular member (13) that is fixed in a cam-distal region of the bore (4) of the housing (3), wherein only one compression spring as a lost motion spring means (16) extends in a cylindrical hollow space (15) formed between an underside (14) of the bottom (2) of the hou…