A tensioner that has a base adapted to be secured to an engine, and at least one arm hinged to a pin fixed to the base and bearing a pulley adapted to cooperate with a belt of a transmission of the engine, and elastic means for pushing the at least one arm in a direction so as to keep the pulley against the belt. The tensioner has sensor means for acquiring in real time a plurality of data relating to the tensioner to estimate the state of efficiency of the same.

A belt-tensioning device includes an electric machine having a drive belt pulley, which is driven about a drive axis, and a further drive belt pulley, where an endless belt wraps around the drive belt pulleys. The device has a housing in which a first and a second spring arm are mounted, in each of which spring arms a tension roller having axes of rotation which are parallel to the drive axis is rotatably mounted. The spring arms are supported against one another and press the endless belt together via the tension rollers in the region of the drive belt pulley. A first and a second further spring arm are provided adjacent to the spring arms which are adjustable by an adjustment element such that the spring forces of the further spring arms either do or do not support the spring forces of the spring arms acting on the endless belt.

A stack of disk springs are placed between a second piston of a dual hydraulic variable force tensioner system and a hydraulic tensioner arm to allow much higher spring rates if desired. The springs may be stacked in multiple configurations to provide different spring rates. Package space can be reduced depending on the number of springs and orientations of said springs within the tensioner arm.

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.

Based on further ingenuity, it is possible to support a heavy and large electric motor on an engine body with sufficient strength while driving the electric motor with a belt without slipping, thereby providing a more streamlined industrial hybrid engine. The industrial hybrid engine is provided with an endless rotation band wound around a drive pulley of a crankshaft and a motor pulley of an electric motor for motive power. The electric motor is attached to an engine case in a position-fixed state using one support bracket. The support bracket includes first and second support portions for attaching the electric motor, and attachment portions positioned between the first and second support portions for attaching the electric motor to the engine case.

A belt tensioning device comprises a base member having an attachment portion and an opening for a drive shaft; first and second tensioning arms that are pivotably supported by first and second bearings on the base member around first and second pivot axes and have first and second tensioning rollers 5, 7. A spring arrangement pretensions the two tensioning arms in a circumferential direction towards each other; wherein the spring arrangement has at least one bow-shaped spring that has a circumferential extension of less than 360° around the first and the second pivot axis; wherein the at least one bow-shaped spring has first and second support portions that are supported on the first and second tensioning arm as well as a spring portion extending between the first and second support portion; wherein the at least one bow-shaped spring has an axial length in the area of the first and the second support portion which is axially shorter than a total axial length of the bow-shaped spring.

A chain tensioning device which combats natural build-up of chain slack. In controlling the chain slack, the torque at which a chain jumps occurs is delayed resulting in a higher jump torque performance.

A belt tensioning device includes a base body. A first tensioning arm is mounted on the base body such that it can pivot about a first pivot axis and which has a rotatable first tensioning roller. A second tensioning arm is pivotably mounted relative to the base body about a second pivot axis and which has a rotatable second tensioning roller. A spring arrangement is arranged between the first tensioning arm and the second tensioning arm and via which the first tensioning arm and the second tensioning arm 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 chain tensioning device which combats natural build-up of chain slack. In controlling the chain slack, the torque at which a chain jumps occurs is delayed resulting in a higher jump torque performance.

A tensioning device for a traction drive comprises: a base member; at least one tensioning arm pivotably supported on the base member around a pivot axis, with a tensioning roller which is rotatably supported on a bearing carrier of the tensioning arm; spring means for resiliently loading the tensioning arm, wherein the spring means extend between a first spring support of the tensioning arm and a second spring support of the tensioning device over a circumferential length around the pivot axis; an adjusting mechanism for adjusting the first spring support relative to the bearing carrier of the tensioning roller in circumferential direction about the pivot axis. A method includes adjusting the torque of the tensioning device.