In one example, an apparatus includes a plate configured to pivot about a pivot point, a pulley coupled to a first planar side of the plate and configured to rotate a belt, a motor coupled to the first planar side of the plate and configured to drive the pulley, and a torsion spring coupled to a second planar side of the plate that is opposite the first planar side and configured to apply tension to the belt.

Described embodiments include a reconfigurable belt tensioner that can be used to add, remove, and/or reposition peripheral accessories of an engine installation, for example, in an automobile or another vehicle. The tensioner has a housing, an arm with an axle, and a spring installed in the housing. The axle is inserted into and fastened to the housing. The arm rotates around the axle. When the arm is rotated, the spring provides the force that tends to return the arm and the housing to the original position. The tensioner can be reconfigured by repositioning the spring relative to the housing and/or the arm, changing the angle between the housing and the arm. The tensioner may be used, for example, on an LS-based GM small-block engine, and allow operation with and without the air conditioning compressor or other accessories.

A tensioner comprising a base, a pivot arm pivotally engaged with the base, a pulley journalled to the pivot arm, a torsion spring engaged between the base and the pivot arm, the torsion spring comprising a planar cylindrical portion integrally formed into an end of the torsion spring, and a damping member engaged with the planar cylindrical portion, the damping member frictionally engaging the base and being loaded in an unwinding direction.

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.

A tensioner comprising a base, a shaft extending from the base, a pivot arm pivotally engaged with the shaft, a torsion spring disposed between the pivot arm the base, a base portion cooperatively engagable with a pivot arm portion upon an axial movement of the pivot arm to a first position, a removable member engaged with the shaft to retain the pivot arm in the first position, the first position limiting the pivot arm to a first range of movement, and the pivot arm axially moveable to a second position upon removal of the removable member, the second position limiting the pivot arm to a second range of movement.

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 with a bracket, a tensioner body coupled to the bracket for rotation about a first axis, a first and second wheels that are coupled to the tensioner body for rotation about second and third axes, respectively, that are parallel the first axis, and a spring that biases the second wheel along a line of action relative to the tensioner body. The second wheel is coupled to the tensioner body for movement between first and second positions along the line of action.

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 tensioner includes a power spring, and a backup member being in contact with the power spring and supporting the power spring by acting an urging force in a direction opposite to a radial shift of the power spring in a direction in which the power spring is wound. The power spring is unwound in a condition in which an inter-plate frictional force of the power spring is small in a case where an urging force acting from a power spring to a tension member is greater than a load acting from the tensioner arm to the power spring and the power spring is wound in a condition in which the inter-plate frictional force of the power spring is large in a case where the urging force acting from the power spring to the tension member is smaller than the load acting from the tension member to the power spring.