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.

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 belt tensioning device includes a first tensioning arm mounted on a base body pivotably about a first pivot axis and includes a rotatable first tensioning roller. A second tensioning arm is pivotably mounted relative to the base body about a second pivot axis and includes a rotatable second tensioning roller. Via a spring arrangement between the first tensioning arm and the second tensioning arm, the first and second tensioning arms are resiliently supported against one another in the circumferential direction. A damping mechanism is operatively arranged between the base body and the first tensioning arm for damping relative rotational movement between the first tensioning arm and the base body. The damping mechanism generates a varying damping torque dependent on the rotational position and/or rotational direction of the first tensioning arm relative to the base body upon pivoting of the first tensioning arm relative to the base body.

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 tensioner includes a base, a tension arrangement rotatable at the base, a damping member being rotated in a loading direction by the tension arrangement, and an elastic member biasing against the damping member. The position of the damping member depends by the layout geometry of the specific application and is directly in opposition to the hub load. The reaction force of the cylindrical surface of the base on the damping member is very near to the plan of the external forces represented by the hub load to minimize the deflection of the shaft. The tension arrangement is rotated to push the damping member for generating a first positive tension between the damping member and the base, and to expand the elastic member radially for generating a second positive tension between the elastic member and the damping member, so as to enhance a damping force of the tensioner.

In an aspect, a system is provided for controlling tension in an endless drive member, and including an isolation device and a tensioning system. The isolation device is positioned on an accessory drive shaft and has a pulley and a biasing member to transfer force from the pulley to the accessory drive shaft. The isolation device pulley is engaged with the endless drive member, such that a first span of the endless drive member is on a first side of the isolation device pulley and a second span of the endless drive member is on a second side of the isolation device pulley. The tensioning system has a first tensioner pulley engaged with the first span and a second tensioner pulley engaged with the second span. The first and second tensioner pulleys are urged by first and second tensioner pulley biasing forces towards the first and second spans respectively.

A tensioner comprising a base having a shaft and having a radially projecting tab therefrom, a pivot arm pivotally engaged with the shaft about a pivot axis A-A, a torsion spring disposed between the base and the pivot arm, the torsion spring in a compressed state, a pulley journalled to the pivot arm, a first axial member extending from the pivot arm, the first axial member comprising a radially projecting portion adjacent to a radially receding portion, and the radially projecting portion engaging the radially projecting tab in a first pivot arm position and the radially receding portion cooperating with the radially projecting tab in a second pivot arm position.

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 tensioning device comprising a receiver housing, a lever arm mounted on the receiver housing and rotatable with respect to the receiver housing around a first rotation axis, a pulley mounted on the lever arm and rotatable with respect to the lever arm around a second rotation axis parallel to the first rotation axis, and a spring mounted between the receiver housing and the lever arm and adapted to apply a torque for rotating the lever arm around the first rotation axis. The receiver housing and the lever arm are screwed together around the first rotation axis. The spring applies an axial damping effort, parallel to the first axis, on cooperating threaded portions respectively provided on the receiver housing and on the lever arm.

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.