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 0 up to approximately 10,000.

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 0 up to approximately 10,000.

In an aspect, a tensioner is provided for tensioning a belt and includes first and second tensioner arms having first and second pulleys respectively. The first and second pulleys are configured for engagement with first and second belt spans, and are biased in first and second free arm directions respectively. A second tensioner arm stop is positioned to limit the movement of the second tensioner arm in a direction opposite the second free arm direction. The second tensioner arm stop is positioned such that, in use, the second pulley is engaged with the endless drive member while the second tensioner arm is engaged with the second tensioner arm stop throughout a first selected range of operating conditions.

In an aspect, a tensioner includes a shaft and base unit that is mountable to an engine, an arm pivotable about the shaft and base unit, a pulley on the arm engageable with a belt, a spring urging the arm in a free arm direction, a first damping member fixed on the shaft and base unit, which receives a first radial force from a first segment of the spring causing a first amount of frictional force between the first damping member and a surface that moves with the tensioner arm, and a second damping member on the arm, which receives a second radial force from a second segment of the tensioner spring that is spaced axially from the first segment of the spring, causing a second amount of frictional force between the second damping member and a surface that is stationary with the shaft and base unit.

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 self-aligning tensioner (1) for an endless traction mechanism drive in an internal combustion engine is provided, including a base unit (2) and a separate annular tensioning arm (3), the tensioning arm (3) being slidably mounted in a sliding bearing area (4) of the base unit (2) in order to allow a rotational movement relative to the base unit (2); at least one spring element (5, 6) that tensions the base unit (2) and the tensioning arm (3) against each other is inserted between the sliding bearing area (4) of the base unit (2) and the tensioning arm (3).

A pendulum tensioner, comprising a first and second tensioning arm, and a bearing sleeve configured to attach to a generator housing, wherein the bearing sleeve forms a sliding channel together with a locking sleeve, in which one of the tensioning arms is rotatably positioned with axial play.

A tensioner comprising a base having a base aperture, the base aperture having an axis A-A and capable of receiving a driven component, a rotary arm rotatably engaged with the base and encircling the base aperture, a swing arm pivotally engaged with the rotary arm, a first torsion spring biasing the swing arm, a first pulley journalled to the swing arm, a rotary ring rotatably encircling the base aperture and disposed between the rotary arm and the base, a second pulley journalled to the rotary ring, a second torsion spring engaged between the rotary ring and the rotary arm for biasing the rotary ring, and a wave spring in pressing engagement between the base and the rotary ring.

A belt tensioner for a belt drive of a motor vehicle engine, comprising: a fixed part configured to be fixed with respect to the engine and provided with a pivot defining a rotation axis; an arm having a connection portion hinged to the pivot and rotatable about the rotation axis and an opposite portion rotatably supporting a pulley configured to cooperate with a belt of the drive; a main spring interposed between the fixed part and the arm to exert thrust on the arm such as to rotate said arm towards the belt; and at least one rolling bearing interposed between the arm and the pivot to support the arm and ensure the alignment thereof.

The invention relates to a belt or chain tensioner (1) for a belt or chain drive of an internal combustion engine, having a base unit (2), an annular tensioning arm (3) which is mounted so as to be rotatable relative to the base unit (2) about an axis of rotation and on which a tensioning roll (4) prepared for pre-tensioning a section of an endless belt or chain is arranged, and two interconnected bearing parts (5, 6), by which the tensioning arm (3) is pivotally mounted on the base unit (2), and the bearing parts (5, 6) are designed as identical parts.