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 formed by an internal bulge within the piston; a check valve retainer within the piston, and a moveable disk that is received between the disk seat formed by the internal bulge and the check valve retainer and is moveable between a first position and a second position, and a check valve spring that is received between the check valve disk and the check valve retainer.

Abstract: An integrated valve for a hydraulic tensioner includes a pressure relief valve with an integrated band, which is preferably made of metal, placed around the outside of a pressure relief valve body. A hydraulic tensioner includes a housing with a bore and a hollow piston slidably received within the bore. A piston spring biases the piston in a direction toward a power transmission device. The tensioner also includes an integrated check valve in a body of the housing. The integrated check valve includes a pressure relief valve mechanism and a band check valve mechanism surrounding a circumference of the pressure relief valve mechanism. The pressure relief valve mechanism permits transfer of pressurized fluid from a piston chamber formed by the hollow piston to the source of pressurized fluid and the check valve mechanism permits transfer of pressurized fluid from the source of pressurized fluid to the piston chamber.

Abstract: A clip lock for securing an expandable clip of a chain tensioner includes an elongated member having a first surface configured to engage an exterior surface of the chain tensioner and a second surface, spaced apart from the first surface, that is configured to engage the expandable clip and maintain the expandable clip in contact with an annular groove of a chain tensioner component preventing radially-outward expansion and axial movement of the expandable clip with respect to the chain tensioner component while the first surface engages that exterior surface of the hydraulic tensioner and the second surface engages the expandable clip.

Abstract: A sealed tensioner is used in an automotive application to keep a belt or chain under its intended tension as it wears and stretches. The sealed tensioner is hydraulic but lacks an outside oil supply. The sealed tensioner, in an example, includes an outer body having a first bore. A cartridge body is received in the first bore. The cartridge body has a second bore. A piston is carried in the second bore. A check valve is situated between a low pressure reservoir and a high pressure chamber. One or more baffle walls are located at the low pressure reservoir. The baffle wall(s) block an air pocket in the low pressure reservoir from entering the high pressure chamber.

Abstract: A pressure regulator is in fluid communication with a supply inlet of a hydraulic tensioner to actively control fluid to the inlet of the hydraulic tensioner. By actively controlling the pressure regulator based on engine conditions and thus the oil pressure being fed to the hydraulic tensioner, the oil pressure to the hydraulic tensioner may be reduced at low engine speeds, increasing the efficiency of the timing system, or allowing full oil pressure at high engine speeds and low engine temperature.

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 formed by an internal bulge within the piston; a check valve retainer within the piston, and a moveable disk that is received between the disk seat formed by the internal bulge and the check valve retainer and is moveable between a first position and a second position, and a check valve spring that is received between the check valve disk and the check valve retainer.

Abstract: A clip lock for securing an expandable clip of a chain tensioner includes an elongated member having a first surface configured to engage an exterior surface of the chain tensioner and a second surface, spaced apart from the first surface, that is configured to engage the expandable clip and maintain the expandable clip in contact with an annular groove of a chain tensioner component preventing radially-outward expansion and axial movement of the expandable clip with respect to the chain tensioner component while the first surface engages that exterior surface of the hydraulic tensioner and the second surface engages the expandable clip.

Abstract: This invention pertains to the field of hydraulic tensioners. A hydraulic tensioner of this invention includes a tensioner body having a bore in fluid communication with a source of pressurized fluid through an inlet, a hollow piston slidably received within the bore and having an outer diameter, a hydraulic pressure chamber defined by the hollow piston and the bore of the tensioner body, a piston spring received within the hydraulic pressure chamber for biasing the piston away from the inlet, and a metallic band surrounding the outer diameter of the piston. The metallic band forms a seal between an outer surface of the piston and the tensioner body when pressure builds in the hydraulic pressure chamber, wherein metallic bands or seals are placed over a hydraulic tensioner piston in order to seal the high pressure chamber and prevent or reduce leakage through the clearance between the piston and the tensioner body.

Abstract: Hydraulic tensioner device including a tensioner arm and a hydraulic tensioner. The tensioner arm comprising: a body having a first end, a second end, a chain sliding surface and a surface opposite the chain sliding face; a pivot at the first end or the second end of the body; and a banjo bolt feed at the other of the first end or second end of the body. The hydraulic tensioner being pivotably attached to the pivot and the banjo bolt and adjacent the surface opposite the chain sliding face, wherein the hydraulic tensioner receives supply fluid from the banjo bolt, the hydraulic tensioner comprising: a housing with a bore; a hollow piston having a first end and a second end, slidably received within the bore; and a spring received within the bore of the housing and the hollow piston biasing the hollow piston outwards from the bore of the housing.

Abstract: A piston assembly for a tensioner which has a hollow piston body having a first end and a second end; and a cap. At least a portion of the cap fits into the first end of the piston body. The cap has a head and may also have a stem connected to an underside of the head. The cap may also have at least one slit for venting fluid, having 5 a width and a depth. The slit may extend from an outer circumference of the stem and across the underside of the head. The slits may be parallel to a centerline of the cap or angled relative to the centerline of the cap. A plurality of slits may be present on the cap. At least two of the plurality of slits may have different widths or different depths. The slits may be evenly 10 spaced around the cap.

Abstract: An integrated valve for a hydraulic tensioner includes a pressure relief valve with an integrated disk check valve surrounding the pressure relief valve. A hydraulic tensioner includes a housing with a bore and a hollow piston slidably received within the bore. A piston spring biases the piston in a direction toward a power transmission device. The tensioner also includes an integrated check valve in a body of the housing. The integrated check valve includes a pressure relief valve mechanism and a disk check valve mechanism surrounding a circumference of the pressure relief valve mechanism. The pressure relief valve mechanism permits transfer of pressurized fluid from a piston chamber formed by the hollow piston to the source of pressurized fluid and the check valve mechanism permits transfer of pressurized fluid from the source of pressurized fluid to the piston chamber.

Abstract: A pressure regulator is in fluid communication with a supply inlet of a hydraulic tensioner to actively control fluid to the inlet of the hydraulic tensioner. By actively controlling the pressure regulator based on engine conditions and thus the oil pressure being fed to the hydraulic tensioner, the oil pressure to the hydraulic tensioner may be reduced at low engine speeds, increasing the efficiency of the timing system, or allowing full oil pressure at high engine speeds and low engine temperature.

Abstract: An integrated valve for a hydraulic tensioner includes a pressure relief valve with an integrated disk check valve surrounding the pressure relief valve. A hydraulic tensioner includes a housing with a bore and a hollow piston slidably received within the bore. A piston spring biases the piston in a direction toward a power transmission device. The tensioner also includes an integrated check valve in a body of the housing. The integrated check valve includes a pressure relief valve mechanism and a disk check valve mechanism surrounding a circumference of the pressure relief valve mechanism. The pressure relief valve mechanism permits transfer of pressurized fluid from a piston chamber formed by the hollow piston to the source of pressurized fluid and the check valve mechanism permits transfer of pressurized fluid from the source of pressurized fluid to the piston chamber.