Patent number: 10436291

Tensioner with spring force control in a second bore

Original Assignee: BorgWarner Inc.

Field of technology: Vehicles, Engines and Transportation

Patent granted on: Tue, 08 Oct 2019

Patent drawing

Abstract

A tensioner for tensioning a chain span which uses two pistons. The movement of the two pistons may be coupled together. The first piston provides damping to the chain span and a second piston provides variable, dominant and automatically adjusting spring force to the chain span. The tensioner automatically adjusts the mean tension force to keep the chain tension as low as possible without sacrificing chain control, significantly improving drive efficiency at new chain conditions and conditions with dynamic loads.