Described herein is a tensioner device, and assemblies and methods of manufacture thereof. The tensioner device may be adapted to create a target tension in an associated belt based on the measured length of the belt. The tensioner device may include an engagement member having a surface adapted to engage the belt and a biasing element associated with the engagement member. The biasing element has a loaded configuration that causes the engagement member to exert a force on the belt to create the target tension. In one example, the biasing element is manipulated into a loaded configuration so that the biasing element exhibits a deflection and an effective spring rate for creating the target tension. The belt may be trapped within the tensioner device with a bracket assembly enclosing one or more runs of belt relative to the engagement member.

Described herein is a tensioner device, and assemblies and methods of manufacture thereof. The tensioner device may be adapted to create a target tension in an associated belt based on the measured length of the belt and/or measure characteristics of a biasing element, such as a stiffness of the biasing element. A biasing element may exhibit a measured stiffness and be associated with a damping assembly and a base of the tensioner device. An engagement member may be associated with the damping assembly for movement therewith and angularly displaceable relative to the base and the biasing element to tension the belt. In one example, the biasing element may be connected to the damping assembly at a position determined by the measured stiffness to define a value of the angular displacement of the engagement member relative to the biasing element and create a target tension in the belt.

A tensioning system including a base and an arm pivotally coupled to the base, the arm having an engagement surface and being configured to pivot relative to the base about a pivot axis. The system further includes a biasing mechanism operatively coupled to the arm to bias the arm relative to the base, and a seal assembly sealingly positioned between the arm and the base. The seal assembly is coaxial with the pivot axis and configured to accommodate relative axial movement between the base and the arm and relative radial movement between the base and the arm while still maintaining a seal therebetween.

A tensioner comprising a base having a base aperture, the base aperture disposed to receive a driven component, a rotary arm pivotally engaged with the base, an axis of rotation of the rotary arm aligned with a base aperture center, a first pulley journalled to the rotary arm, a swing arm pivotally engaged with the rotary arm about a shaft, the shaft and swing arm each having cooperating frustoconical portions, a torsion spring biasing the pivot arm, a second pulley journalled to the swing arm, a bushing having a frustoconical portion in frictional engagement with the swing arm frustoconical portion, the bushing in fixed relation to the shaft or pivot arm, and a first damping ring frictionally engaged between the rotary arm and the base, a Belleville spring in pressing engagement whereby a normal force is applied to the first damping ring.

A tensioner comprising a base, a shaft press fit into the base, a pivot arm journalled to the shaft, the pivot arm having a first frustoconical portion and a frustoconical bushing disposed thereon, a pulley journalled to the pivot arm, a torsion spring engaged between the base and the pivot arm for biasing the pivot arm, a seal disposed between the base and pivot arm on the shaft, the shaft comprising a second frustoconical portion describing an apex angle Δ, and the torsion spring applying an axial spring force to the pivot arm such that the first frustoconical portion is in pressing engagement with the second frustoconical portion.

A tensioner comprising a base, a ring engaged with the base, the ring rotatable about a center “C” within a base opening, a pulley journalled to the ring, a pivot arm pivotally engaged with the ring, a pulley journalled to the pivot arm, a torsion spring disposed between the ring and the pivot arm for urging the pivot arm, a damping assembly frictionally disposed between the base and the ring, a spring applying a normal load to the damping material, and the damping material having a resistance in the range of greater than 0Ω up to approximately 10,000Ω.

A tensioning system including a base and an arm pivotally coupled to the base, the arm having an engagement surface and being configured to pivot relative to the base about a pivot axis. The system further includes a biasing mechanism operatively coupled to the arm to bias the arm relative to the base, and a seal assembly sealingly positioned between the arm and the base. The seal assembly is coaxial with the pivot axis and configured to accommodate relative axial movement between the base and the arm and relative radial movement between the base and the arm while still maintaining a seal therebetween.

A tensioner uses a low rate torsion spring in a first stage and a high rate torsion spring in a second stage to maintain tension in a chain or belt. The first stage is connected to the second stage by a torque coupling. The high rate torsion spring is maintained in an energized state between a ground and a dead stop to store energy and to provide tension under high loads. In some embodiments, the torque coupling is a damper. In other embodiments, the torque coupling is a clutch. A method stores energy in a high rate torsion spring of a tensioner.

In an aspect, a tensioner is provided for an endless drive member, and includes a shaft-and-base unit, a tensioner arm, a pulley, and a tensioner spring. The shaft-and-base unit is mountable to be stationary relative to an engine, and includes a fastener aperture for a fastener. The tensioner arm is pivotable relative to the shaft-and-base unit about a tensioner arm axis. The pulley is rotatably mounted to the tensioner arm for rotation and is engageable with an endless drive member. The tensioner spring is positioned to urge the tensioner arm in a first direction relative to the shaft-and-base unit. The tensioner spring includes a plurality of coils that are arranged generally helically about a longitudinal axis and are spaced radially from one another and generally increase in distance away from the axis in a longitudinal direction.

A belt tensioner having a tensioner base and a tensioning arm axially aligned about a pivot shaft defining a pivot axis, the tensioning arm pivotal in relation to the tensioner base about the pivot axis. The tensioner has a bearing positioned around and sealed against the pivot shaft, with the tensioning arm positioned around the bearing. The bearing forms a radial seal between the bearing and the tensioning arm and between the bearing and the pivot shaft. A torsion spring is positioned externally around a portion of the tensioning arm.