Patent ID: 7146955
Filing Date: 2006-12-12
Classification: F01L

Abstract:
1. A hydraulic tappet clearance compensation device ( 1 ), comprising a canister-shaped housing ( 2 ), running in the bore ( 3 ) of which is a hollow-cylindrical pressure piston ( 5 ), axially moveable in relation to said housing and enclosing a hydraulic fluid reservoir ( 4 ), a high pressure chamber ( 8 ) for hydraulic fluid being formed between a bore-side piston ring land ( 6 ) of the pressure piston ( 5 ) and a base ( 7 ) of the housing ( 2 ), the piston ring land ( 6 ) having a central bore ( 9 ), which is provided on a high pressure chamber side ( 17 ) of the piston ring land ( 6 ) with a non-return valve ( 10 ) opening in the direction of the high pressure chamber ( 8 ) and radially outside which piston ring land ( 6 ) an annular collar ( 11 ) protrudes axially towards the high pressure chamber ( 8 ), a leakage gap ( 13 ) for the hydraulic fluid from the high pressure chamber ( 8 ) being formed between an outer shell ( 12 ) of the pressure piston ( 5 ) and the bore ( 3 ) of the housing ( 2 ), the base ( 7 ) of the housing ( 2 ) forming a stop face ( 14 ) for the annular collar ( 11 ) of the pressure piston ( 5 ) in the sunken position thereof and the bore ( 3 ) of the housing ( 2 ) running out in an annular enlargement ( 15 ) in the section thereof adjoining the stop face ( 14 ), wherein that the annular collar ( 11 ) has a radial opening ( 16 ) or multiple radial openings ( 16 ) distributed over the circumference; wherein that the annular collar tapers conically on the outside ( 22 ) thereof.