A tensioning system including a magnetic stop is provided. The tensioning system includes a tensioner arm and a support. The tensioner arm is mounted on the support for pivoting movement. The support includes a support magnetic or ferromagnetic element on at least a first surface thereof. The tensioner arm includes a tensioner arm magnet on at least a second surface thereof that faces the first surface of the support.

In an aspect a tensioner is provided for a belt drive and includes a base, an arm with a pulley pivotally mounted to the base, and a biasing member. The pulley is rotatably mounted to the arm. The belt applies a hub load on the pulley and thereby applies a hub load moment on the arm along a first moment arm. The biasing member applies a biasing member moment on the arm along a second moment arm that is at least about 50 percent of the length of the first moment arm. The tensioner is mountable to an accessory frame via fasteners that each have a center distance from an accessory pulley axis, wherein the center distance is a value that is less than about 25 mm greater than the frame body diameter.

In an aspect, a tensioner for an endless drive member, comprising a shaft and base that are mountable to be stationary relative to an engine, a tensioner arm that is pivotable relative to the shaft about a tensioner arm axis, a pulley on the tensioner arm rotatable about a pulley axis that is offset from the tensioner arm axis, and that is engageable with an endless drive member, a tensioner spring that is positioned to urge the tensioner arm towards a free arm position, a damping element that engages the tensioner arm and that is engaged by a plurality of axially spaced segments of the tensioner spring.

A belt tensioning device for a belt drive comprises a base member that is firmly connectable to a stationary component; at least one tensioning arm, which is pivotably supported relative to the base member around a pivot axis; a spring element, with which the tensioning arm is supported elastically in circumferential direction, wherein the ratio of the nominal diameter to the axial length of the spring element is larger than 3.0 in the mounted condition; and a tensioning roller for tensioning the belt, which is rotatably supported on the tensioning arm around an axis of rotation; wherein the base member and the tensioning arm are each at least partially made from plastic material.

A tensioner comprising a base, a shaft connected to the base, an eccentric adjuster coaxially engaged with the shaft, an arm pivotally engaged with the shaft, a pulley journalled to the arm, a torsion spring engaged between the arm and the base, the arm comprising a first receiving portion and a second receiving portion disposed axially opposite from the first receiving portion, a first damping member disposed between the arm and the base, the first damping member frictionally engaged with the base and engaged with first receiving portion, a second damping member disposed between the arm and the eccentric adjuster having a member engaged with the second receiving portion, and a biasing member disposed between the first damping member and the arm for applying a normal force to the first damping member and to the second damping member.

A vehicular final drive chain path length compensation and adjustment system using an idler assembly which is moved in a prescribed geometry by a stiff system. The system and method maintains constant the chain path length during suspension travel. An idler arm assembly guides the idler assembly along an arc-shaped path, with displacement along this path determined not by a spring, but by a cam rotated by a trailing arm on the vehicle. The idler arm assembly allows for a simple static adjustment to compensate the chain path length for wear of components and tolerances in the vehicle assembly.

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.

High-offset belt tensioners have a support base with a pivot tube and an arm coupled thereto rotation about a pivot axis. A flat wire torsion spring has an inner spring hook attached to the pivot tube and an outer spring hook attached to a first end of the arm at a position that counterbalances a hub load force. The torsion spring applies a spring force to the arm in a direction that moves with the arm throughout its entire sweep in a belt engaging direction. A first plane of the hub load force is axially offset from a second plane of the spring force, a fulcrum is defined between first and second ends of the arm, and a first lineal axial distance from the fulcrum to the first plane is greater than or equal to a second lineal axial distance from the fulcrum to the second plane.

A belt tensioner is disclosed that has a spring case defining a receptacle for a torsion spring and having an arm extending radially outward and axially rearward therefrom and terminating with a bore configured for fastening the spring case directly to an engine. The belt tensioner has a support base non-rotationally connected to the spring case through a pivot tube. The pivot tube defines a first axis of rotation, and a pulley mount of the support base defines a second axis of rotation. The support base includes at least one fastener bore for connection to the engine. An arm is coupled to the support base for rotation about the first axis in response to a spring force applied by a torsion spring seated within the spring case and has a free end that defines a pulley mount that defines a third axis of rotation.