BorgWarner Inc.
Tensioner with stiffness controllable check valve

Abstract:

A hydraulic tensioner for an internal combustion engine for tensioning a span of a chain or a belt has a piston with an internal reservoir connected to a high pressure chamber through a check valve assembly. The check valve assembly has a disk seat received within the hollow bore of the body of the piston having at least one passage connecting the internal reservoir to the hydraulic pressure chamber; a check valve retainer coupled to the disk seat; a check valve disk received between the disk seat and the check valve retainer moveable between a first position and a second position, and a check valve spring received between the check valve disk and the check valve retainer.