Abstract: A hydraulic tensioner having a piston sliding around an outside surface of a pin or rod, so that the high pressure chamber for chain control is created by the area between the piston internal diameter and the rod outside diameter. A spring around the outside of the rod presses against the bottom of the piston, biasing the piston outward during low oil pressure conditions. Preferably, the piston is steel and the rod is aluminum, the reverse of prior art designs, which means that as temperature increases, the piston to bore clearance reduces. This can offset the oil viscosity reduction and maintain the same performance over operating temperatures.

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.

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 tensioner which adjusts the mean tensioner force to keep the chain tension as low as possible without sacrificing chain control, significantly improving drive efficiency as the chain wears and is subject to low dynamic loads.

Abstract: A press-fit check valve for a hydraulic tensioner includes a retainer, a seat, a ball, and a spring. The seat of the check valve is press-fit against the wall of the check valve counterbore of the hydraulic tensioner body. In some embodiments, the seat is cup-shaped to provide a predetermined level of press force retention of the press-fit check valve. In some embodiments, the seat includes a plurality of legs separated by leg openings. In some embodiments, a backflow path is provided past the press-fit check valve by a combination of the leg openings and at least one backflow slot through a flange of the retainer. In some embodiments, a lip at the outer end of the check valve counterbore prevents the seat from backing out of the check valve counterbore.

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 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.

Abstract: A tensioner which adjusts the mean tensioner force to keep the chain tension as low as possible without sacrificing chain control, significantly improving drive efficiency as the chain wears and is subject to low dynamic loads.

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.

Abstract: A valve operating system that includes a plurality of cam assemblies that are coupled for rotation about a rotary axis. Each of the cam assemblies has a control link and a first cam member. Each of the control links has a link body, which forms a majority of the control link, and that extends parallel to the rotary axis. Each of the first cam members is coupled to one of the control links for axial movement therewith along the rotary axis between first and second positions to alternate between first and second cam profiles, respectively.

Abstract: A sealed hydraulic tensioner includes a cylinder having a cylinder surface formed in a housing; a piston, received by the cylinder, having an inner surface forming a piston cavity and an outer surface that closely conforms in shape to the cylinder inhibiting the flow of fluid between the outer surface of the piston and the cylinder surface; a tensioner biasing member engaging the piston and the cylinder forcing the piston in an axial direction; a check valve regulating fluid flow between a high-pressure chamber and a low-pressure chamber; one or more apertures formed in the piston extending between the inner surface and the outer surface of the piston that communicate fluid between the piston cavity and the cylinder, wherein a substantially fixed quantity of fluid is encapsulated within the piston cavity and the cylinder.

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.

Abstract: A tensioner which adjusts the mean tensioner force to keep the chain tension as low as possible without sacrificing chain control, significantly improving drive efficiency as the chain wears and is subject to low dynamic loads.

Abstract: A press-fit check valve for a hydraulic tensioner includes a retainer, a seat, a ball, and a spring. The seat of the check valve is press-fit against the wall of the check valve counterbore of the hydraulic tensioner body. In some embodiments, the seat is cup-shaped to provide a predetermined level of press force retention of the press-fit check valve. In some embodiments, the seat includes a plurality of legs separated by leg openings. In some embodiments, a backflow path is provided past the press-fit check valve by a combination of the leg openings and at least one backflow slot through a flange of the retainer. In some embodiments, a lip at the outer end of the check valve counterbore prevents the seat from backing out of the check valve counterbore.

Abstract: A tensioner which adjusts the mean tensioner force to keep the chain tension as low as possible without sacrificing chain control, significantly improving drive efficiency as the chain wears and is subject to low dynamic loads.

Abstract: A valve operating system that includes a plurality of cam assemblies that are coupled for rotation about a rotary axis. Each of the cam assemblies has a control link and a first cam member. Each of the control links has a link body, which forms a majority of the control link, and that extends parallel to the rotary axis. Each of the first cam members is coupled to one of the control links for axial movement therewith along the rotary axis between first and second positions to alternate between first and second cam profiles, respectively.

Abstract: A tensioner for tensioning a chain or belt 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 or belt tension as low as possible without sacrificing chain or belt control, significantly improving drive efficiency at new chain or belt conditions and conditions with dynamic loads.

Abstract: A tensioner which adjusts the mean tensioner force to keep the chain tension as low as possible without sacrificing chain control, significantly improving drive efficiency as the chain wears and is subject to low dynamic loads.

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 tensioner which adjusts the mean tensioner force to keep the chain tension as low as possible without sacrificing chain control, significantly improving drive efficiency as the chain wears and is subject to low dynamic loads.