Abstract: A combination starter-generator system for use in a vehicle is provided. The vehicle has an internal combustion engine and a battery. The system includes a starter-generator electrically coupled to the battery to generate a current and to start the internal combustion engine. A drive mechanism connects the starter-generator machine and the internal combustion engine. The starter-generator machine generates the current by receiving a charging torque from one side of the drive mechanism and starts the internal combustion engine by imparting a starting torque to a different side of the drive mechanism. The charging torque or the starting torque is a greater torque. A passive tensioning system cooperates with the drive mechanism to tension the drive mechanism only at the side of the greater torque.

Abstract: A belt tensioning assembly for use with a power transmission system including a belt extending between a driver pulley and a driven pulley is provided. The tensioning assembly includes an idler engageable with the belt and rotatably attached to a frame pivotally secured to a base for the power transmission system adjacent the driver pulley. A biasing assembly is pivotally attached between the frame and the base for the transmission system and includes a biasing mechanism adapted to urge the idler contact with into the belt. As the tension in the belt changes due to changes in the power demand, the idler is automatically urged with varying force against the slack side of the belt by the biasing mechanism to provide near constant tension on the belt as it moves between the pulleys.

Abstract: The invention is an improved belt drive system of the type having an automatic belt tensioner, an automatic belt tensioner pulley, a crankshaft pulley, an accessory pulley, and a power transmission belt trained about the automatic belt tensioner pulley, the crankshaft pulley, and the accessory pulley. It is improved by the inclusion of an initial tensioner.

Abstract: A traction device for an internal combustion engine includes a tensioning device having two lever arms of different lengths which are rigidly connected together and which are pivotally mounted for rotation about a rotation axis. Each of the lever arms supports on one end a tension pulley. The tensioning device is provided for positioning the tension pulleys on a pulling strand and a return strand by imposing an elastic force thereon.

Abstract: A hydraulic automatic tensioner for adjusting the tension of an endless belt in a power transmitting mechanism for transmitting power to engine accessories of an internal combustion engine through the belt comprises: a fixed first member (11), a piston (PS) formed integrally with the first member (11), a movable second member (12) coaxially combined with the first member (11) so as to be axially movable relative to the first member (11), a cylinder (CY) formed integrally with the second member (12), defining a fluid-reservoir chamber (R) for storing a hydraulic fluid together with the first member (11), and provided with a leak passage (20), axially slidably receiving the piston (PS), a spring (S) pushing the first and the second member (11, 12) away from each other. The piston (PS) and the cylinder (CY) form a pressure chamber (P) filled with the hydraulic fluid.

Abstract: A chain tensioner (10) is disclosed which includes a tensioner arm (18), a face (30) and a blade spring (36). The face and blade spring each have portions which extend beyond a distal end (22) of the tensioner arm. The blade spring maintains contact between the face and a chain (16) as the chain wears.

Abstract: The invention comprises an asymmetric damping tensioner system for belt drives on an engine. A belt is connected between a driver pulley on a crankshaft and any number of driven pulleys. Each driven pulley is connected to an accessory such as an alternator, power steering pump, compressor or the like. The tensioner is placed anywhere before the first component of significant effective inertia, in the belt movement direction. A biasing member in the tensioner is used to maintain a tension in the belt. The tensioner further comprises a damping mechanism to damp belt vibrations caused by the operation of the engine. Tensioner damping friction is unequal or asymmetric, depending upon the direction of movement of the tensioner arm. During acceleration the damping friction of the tensioner in the unloading direction is significantly lower than the damping friction in the opposite, or loading direction, as is the case during deceleration.

Abstract: A drive belt of an internal combustion engine has a first pulley mounted on a crankshaft of the internal combustion engine, and a second pulley mounted on a shaft of a starter generator of the internal combustion engine. A belt is looped about both pulleys. A tensioner includes two tensioning arms, each of which loading a belt run of the belt and operating either as load-carrying belt run or non-load carrying belt run. Both tensioning arms are disposed to pivot about a rotation axis, with tensioning rollers mounted onto the tensioning arms and spring-biased against the belt. The tensioning arm disposed respectively upon the load-carrying belt run is urged into a stop position by a force applied by the belt.

Abstract: The invention comprises a belt drive cantilever tensioner. The tensioner is particularly suited to belt drive systems having a high belt tension. The tensioner comprises a pulley journaled to a cantilever arm. The cantilever arm is pivotably attached to a mounting surface by a fastener at a pivot. The cantilever arm further comprises a hole disposed radially from the pivot for containing an embedded resilient member. A second fastener extends through the resilient member fixing it in a position relative to the first fastener. A load applied to the pulley causes the arm to pivot thereby causing a lever action to exert a force upon the resilient member. The resilient member has a limit of movement as well as an asymmetric force characteristic which increases in proportion to an arm rotation.

Abstract: A tensioner having a base. A spring connected to the base biases a plate, having a pulley, toward a belt. Frictional blocks are aligned on the base in a staggered fashion along a spring centerline. The plate slidingly moves in a linear path between the blocks. The blocks constrain the path of the plate allowing movement in only a single axis parallel to a spring axis. A hubload from a belt running on the pulley combined with the spring force acting on the plate creates a force couple acting on the plate through the frictional blocks. The engaging surfaces between the plate and the blocks have a predetermined coefficient of friction thereby creating a damping force as the pulley and plate move in a linear path on the blocks.

Abstract: A method and system are taught for a tensioner for an endless power transmission belt in an engine. The method and system comprise an AGS pulley and crankshaft pulley coupled to the belt, one of the AGS pulley or the crankshaft pulley operating as a driving pulley that drives the belt so that a tight span and slack span are created in the belt on opposite sides of the driving pulley. The method and system also comprise accessory pulleys coupled to the belt. The tensioner comprises first and second arms, each arm rotatably coupled to a pulley, the pulleys being positioned such that a first one of the pulleys is coupled to the tight span and a second one of the pulleys is coupled to the slack span.

Abstract: A belt tensioner for a power transmission belt is provided that operates on an endless path and that utilizes asymmetric motion control. The belt tensioner has an arm with a belt engaging section and a drum section, a support member for securing the tensioner relative to the belt, where the arm pivots about the support member, and a tension spring that urges the arm to pivot about the support member in a first direction and urges the belt engaging section against the belt with a force to tension the belt. The belt tensioner further comprises a cavity between the arm and the support member and a bushing comprising a bowed flange positioned in the cavity.

Abstract: The invention comprises a method of using tensioners to tune a belt drive system. A tensioner having a damping rate is used on an accessory belt slack side and a tensioner having a having a damping rate is used on an accessory belt tight side. Outside of a predetermined engine speed range, the tight side tensioner arm does not move because the dynamic tension in the span is less than the tight side tensioner friction damping. Within a predetermined engine speed range the tight side tensioner arm moves in order to damp a belt drive system vibration.

Abstract: A combination comprises a belt trained about a plurality of pulleys and a tensioner assembly including a rotary member rotatively engaged by one side of the belt at an operative position. The rotary member is rotatably mounted on an arm pivoted about a fixed pivotal axis and has a rotational axis parallel with the fixed pivotal axis. The vector force applied by the belt to the periphery of the rotary member at the bisector of the belt wrap angle extends through the rotational axis and is related by at least a small angle to a line passing through the rotational and pivotal axis. The vector force acts in a direction to bias the arm to pivot about the pivotal axis in a direction to move the rotary member into the operative position. The rotary member is initially installed into the operative position by moving the arm in the direction from an installation position.

Abstract: A belt tensioner for a power transmission belt may be provided that operates on an endless path and that utilizes asymmetric motion control. The belt tensioner may have an arm with a belt engaging section and a drum section, a support member for securing the tensioner relative to the belt, where the arm pivots on the support member, and a tension spring that urges the arm to pivot about the support member in a first direction and urges the belt engaging section against the belt with a force to tension the belt. The tensioner also may have a fluid filled chamber inside a portion of the drum section of the arm and a valve pivotally attached to the tensioner so that the valve extends across the fluid containing chamber.

Abstract: An idler assembly which is easily removable from a mower deck is disclosed. The idler assembly is rotatably mounted to the mower deck about a shouldered shaft and held in place by an easily removable spring clip. An idler pulley is rotatably attached to the other end of the idler arm. A spring is connected to a spring clip which is secured to the top of the idler arm. The spring causes the idler arm to rotate about the shouldered shaft and forces the idler pulley to apply tension to the drive belt. The idler arm also includes an extension which protrudes beyond the radius of the idler pulley to contact a snubber or bumper. The snubber is secured to the mower deck by a snubber bracket.

Abstract: A belt tensioner having a pivot arm biased toward a belt by a torsion spring. The tensioner also comprises a one-way clutch coupled with a friction clutch. The pivot arm of the tensioner is connected to a one-way clutch. The one-way clutch is cooperatively connected to a friction clutch having a predetermined friction torque caused by frictionally engaged radially extending surfaces. The pivot arm may move relatively freely toward a belt by operation of the one-way clutch. At the limit of arm movement the one-way clutch engages, preventing travel away from the belt in an opposite direction. The arm may only travel away from the belt when a belt tension torque exceeds the spring force plus a friction torque of the friction clutch.

Abstract: A belt tensioner for a power transmission belt is provided that operates on an endless path and that utilizes asymmetric motion control. The belt tensioner has an arm with a belt engaging section and a drum section, a support member for securing the tensioner relative to the belt, where the arm pivots about the support member, and a tension spring that urges the arm to pivot about the support member in a first direction and urges the belt engaging section against the belt with a force to tension the belt. The tensioner also has a stator inside the drum section utilized to form arcuate spaces circumferentially spaced around the stator between the stator and the drum section and arcuate shaped wedges in the arcuate spaces. The tensioner further has a Bellville spring coupled to the arm and a friction device positioned between the wedges and Bellville spring.

Abstract: A belt tensioner for a power transmission belt is provided that operates on an endless path and that utilizes asymmetric motion control. The belt tensioner has an arm with a belt engaging section and a drum section, a support member for securing the tensioner relative to the belt, where the arm pivots about the support member, and a tension spring that urges the arm to pivot about the support member in a first direction and urges the belt engaging section against the belt with a force to tension the belt. The tensioner also has a stator inside the drum section utilized to form arcuate spaces circumferentially spaced around the stator between the stator and the drum section and arcuate shaped wedges in the arcuate spaces.

Abstract: A damping mechanism used in a tensioner for tensioning a power transmission belt including a damping plate having a friction surface, at least one ramp surface and first and second contact points for operatively connecting a spring whereby the spring torque applied to damping mechanism in combination with a reactive force at the pivot surface generates a normal force.

Abstract: A tensioner having a pulley journaled to a housing. The housing further comprises a guide. The guide slidingly engages rails on a base. The guide and rails constrain the housing to move in a predetermined linear path. The rails are horizontally offset from two axis defined by the pulley. The pulley load is also vertically offset from the axis of movement of the guide. The guide and rails have a predetermined frictional coefficient so that the cumulative result is an asymmetric damping effect. Further, a linkage is connected between the housing and a camming body. The camming body is rotatably connected to the base. A biasing member such as a torsion spring biases the camming body against the belt load through the linkage. The radius of the camming body is variable to maintain a constant belt load as the tensioner pulley moves in response to a load change.

Abstract: A tensioner for an endless power transmission belt, the belt being driven about a sheave. The tensioner may comprise a base, a resilient device, and first and second arms pivotally coupled for movement in an open and a closed direction. The tensioner may also comprise first and second pulleys rotatably coupled to the first and second arms, the resilient device biasing the arms in the closed direction in which the first and second pulleys apply tension to the belt. The tensioner may also comprise first and second stops positioned outside the arms on the base to limit the movement of the arms in the open direction in response to an increase in tension in the belt.

Abstract: A belt tensioner for a power transmission belt system includes: (a) a base housing having a pivot shaft extending therefrom; (b) a tension arm pivotally mounted on the pivot shaft at a proximal end thereof, the proximal end of the tension arm including a rub surface and the distal end of the tension arm adapted to contact a power transmission belt; (c) a torsion spring operatively coupled between the base housing and the tension arm and adapted to bias the distal end of the tension arm against the power transmission belt; and (d) a damper assembly coupled to the housing, the damper assembly including: (1) a body of friction material that includes a friction surface adjacent to and facing the rub surface of the tension arm and (2) a damper spring integral with the body of friction material and biasing the body of friction material and associated friction surface against the rub surface of the tension arm.

Abstract: A belt tension adjusting device has a stationary fulcrum shaft, an arm pivotally supported on the fulcrum shaft through a slide bearing formed of a synthetic resin, a tension pulley mounted on the arm at one end thereof for tensioning a belt, and a damper having a piston rod abutting the arm on the other end thereof. The tension pulley is pressed against the belt by pivoting the arm under the force of the piston rod, thereby adjusting the tension of the belt. The inner peripheral surface of said slide bearing, which is in slide contact with said fulcrum shaft, is formed so as to have a surface roughness RA of not more than 6.3 &mgr;m. The slide bearing is formed of a resin composition comprising 65-85 vol % of a thermoplastic polyimide resin, an aromatic polyether ketone resin or a mixture of the resins, and 15-35 vol % of a tetrafluoroethylene resin.

Abstract: A tensioner for a drive belt, having a fixed portion connected rigidly to a supporting structure; a movable portion hinged to the fixed portion about a first axis; a pulley carried by the movable portion and rotating, with respect to it, about a second axis distinct from and parallel to the first axis, a spring interposed between the fixed portion and the movable portion, and for loading, in use, the movable portion to keep the pulley engaged with the belt; and a damping member having a connecting portion fixed rigidly to the fixed portion, and a friction portion cooperating with a seat formed in the movable portion; the tensioner having a single screw for fixing the fixed portion to the supporting structure, and the damping member to the fixed portion.

Abstract: The invention comprises a tensioner that is particularly useful in micro-V front end accessory belt drive systems used in automotive applications where minimum tensioner bulk combined with maximum balancing and minimum pivot bushing wear in order to achieve maximum pulley alignment over the expected life of the tensioner. The belt tensioner of the invention is of the type with a base. A pivot-arm is attached to a cylindrical member that supports the pivot-arm and rotates about a pivot secured to the base. At least one sleeve-type bushing is positioned on the pivot and includes a bearing surface that supports the cylindrical member. A pulley is attached to the pivot-arm for engaging the belt and receives a belt load that generates a belt force component that is transmitted to the cylindrical member (hub load) A torsion spring having one end connected to the base and another end interconnected to a damping means generates a damping force component acting in the opposite direction as the belt force component.

Abstract: A combination belt tensioner and idler has a fixed pivot structure. A moveable arm is mounted for pivotable movement about the pivot structure. A belt tensioning pulley is mounted on the moveable arm. A helical coil spring biases the moveable arm in a direction so as to force the pulley into tensioning engagement with a belt. A mounting bolt mounts the fixed pivot structure on a motor vehicle engine. An idler pulley is mounted for rotational movement about an axis defined by the mounting bolt.

Abstract: The invention comprises a belt tensioner having a pivot arm biased toward a belt by a torsion spring. The tensioner also comprises a one-way clutch coupled with a friction clutch. The pivot arm of the tensioner is connected to a one-way clutch. The one-way clutch is cooperatively connected to a friction clutch having a predetermined friction torque caused by frictionally engaged radially extending surfaces. The pivot arm may move relatively freely toward a belt by operation of the one-way clutch. At the limit of arm movement the one-way clutch engages, preventing travel away from the belt in an opposite direction. The arm may only travel away from the belt when a belt tension torque exceeds the spring force plus a friction torque of the friction clutch.

Abstract: A belt apparatus is provided for use in a document processing system having a baseplate, a removable bearing assembly connected to the baseplate and having a drive pulley to which a drive belt is drivingly coupled. The belt apparatus comprises a bracket coupled to the baseplate and for supporting the drive belt when the bearing assembly including the drive pulley is removed from the baseplate. The bracket supports the drive belt below the baseplate to allow the drive belt and the drive pulley of a replacement bearing assembly to be easily coupled together without having to lift the baseplate to gain access to the space below the baseplate. Preferably, the bracket comprises a substantially U-shaped bracket. The bracket may include a pair of flanges on which the drive belt rests when the bearing assembly is removed from the baseplate. The pair of flanges extend in substantially opposite directions relative to each other and substantially parallel with the plane in which the baseplate lies.

Abstract: The invention comprises a self-contained mechanical belt tensioner that produces damping which is a function of the applied hubload through the effect of frictional forces derived from the sliding action of mutually opposing wedges. A first wedge or conical piston is contained within a housing. The conical piston cooperates with a second or conical wedge. A surface of the conical wedge slides on the inner surface of the housing. The conical wedge is expandable in a direction normal to the inner surface of the housing. A spring urges the conical wedge into engagement with the conical piston. As the pulley is loaded, as with an impulse load, the piston will move into the conical wedge. This, in turn, will cause the conical wedge to expand against the inner surface of the housing. The expansion of the conical wedge in the housing will increase the frictional force between the conical wedge and the housing. This will have the effect of damping movements of the conical piston and, in turn, of the pulley.

Abstract: An idler having a flexible member. The flexible member comprises a rubber or elastomeric material. The flexible member also defines a gas chamber. The spring rate of the flexible member is a function of the flexible material and the size of and pressure in the gas chamber. A belt or chain bearing surface of the flexible member bears upon a belt or chain trained between two pulleys. The flexible member is compressible in response to a preload caused as the idler is pressed against the chain or belt. The flexible member damps vibrations in the belt or chain during operation. This results in quieter operation of the idler/pulley system as well as increases the operating life of the belt.

Abstract: The invention comprises a tensioner having a pulley journaled to a housing. The housing further comprises a guide. The guide slidingly engages rails on a base. The guide and rails constrain the housing to move in a predetermined linear path. The rails are horizontally offset from two axis defined by the pulley. The pulley load is also vertically offset from the axis of movement of the guide. The guide and rails have a predetermined frictional coefficient so that the cumulative result is an asymmetric damping effect. Further, a linkage is connected between the housing and a camming body. The camming body is rotatably connected to the base. A biasing member such as a torsion spring biases the camming body against the belt load through the linkage. The radius of the camming body is variable to maintain a constant belt load as the tensioner pulley moves in response to a load change.

Abstract: An idler assembly which is easily removable from a mower deck is disclosed. The idler assembly is rotatably mounted to the mower deck about a shouldered shaft and held in place by an easily removable spring clip. An idler pulley is rotatably attached to the other end of the idler arm. A spring is connected to a spring clip which is secured to the top of the idler arm. The spring causes the idler arm to rotate about the shouldered shaft and forces the idler pulley to apply tension to the drive belt. The idler arm also includes an extension which protrudes beyond the radius of the idler pulley to contact a snubber or bumper. The snubber is secured to the mower deck by a snubber bracket.

Abstract: Use of the present invention enables the alignment and servicing of the rear derailleur of a bicycle without having the rear wheel or a specialized fixture mounted in the dropouts. For the present invention, the apparatus is placed on the frame of the bicycle and the chain routed over a toothed pulley. A tensioning spring in the apparatus provides the proper chain tension and allows the rear derailleur to be serviced or aligned.

Abstract: An autotensioner comprises a cup-shaped stationary member, an arm rotatably attached to an opening of the stationary member. An axial bore is formed in the bottom of the stationary member. A rocking wall extending to the bottom is provided at the arm. A first friction member is provided between the rocking wall and the inner wall of the opening. The first friction member is gripped between the rocking wall and the inner wall. A rocking shaft extending to the bottom is provided at the center of a lid portion of the arm. The rocking shaft is inserted in the axial bore. A second friction member is provided between the rocking shaft and the axial bore. The first friction member and the second friction member are formed of a synthetic resin mainly comprised of PPS, exhibit high limited PV factors, and exhibit low coefficients of friction.

Abstract: An automotive tension device features a pair of pulleys which are pivotally mounted on the same pivot arm. The pulleys are positioned within the drive system (e.g., a belt drive system) in such a manner that the moments relative to the pivot axis created by the force resultant of the driving member passing around each of the pulleys are oppositely directed. Thus, the pulleys provide rotational support for each other. The tension device and arrangement is positioned within a belt drive system having a combination starter/generator, wherein the crankshaft ordinarily drives the belt but the starter/generator drives the belt on engine startup (an arrangement which creates varying kinematic conditions within the belt).

Abstract: A tensioning device for attraction mechanism including a receiving and mounting housing, a roller carrier pivotably connected to the mounting housing, a bearing which radially supports the roller carrier relative to the mounting housing, a spring between the roller carrier and the mounting housing for applying a tensioning force, and a damping device. The damping device includes a damping bush which, by friction, dampens any movement between the roller carrier and the mounting housing in such a way that damping is greater in the direction of an increasing tension force than in the direction of decreasing tension force. A flat band spring applies the friction force to the damping bush. The flat band spring is secured, at a first end, to the receiving and mounting housing in a rotationally fast way, and at a second end to the damping bush in a rotationally fast way.

Abstract: An autotensioner having a support shaft affixed to a base, and a cup of a swing member provided swingably about the support shaft. The cup opens to the base and houses inside it a torsion coil spring for biasing the pulley in the direction tensioning the belt. A damping member braking the swing member is fixed to the base. A ring-shaped spring brings it into close contact with the inner circumferential surface close to the opening of the cup. The damping member frictionally slides with the inner circumferential surface at the time of swing of the swing member and supports the swing member in the radial direction at the base side from the bearing supporting the support shaft.

Abstract: A continuously variable transmission has an endless V belt (15) running across a driving pulley (11) and a driven pulley (21), a transmission ratio changing mechanism for changing the running diameters of the belt around the pulleys radially in opposite directions to each other, and a tension-adjusting unit (50) for pressing the belt to obtain belt tension. The tension-adjusting unit (50) includes a tension roller (51) coming into pressure contact with the slack side of the belt (15) from outside, a swing arm (53) having an end rotatably supported on a transmission case (6), a link member (52) having an end rotatably supporting a shaft of the tension roller (51) and another end rotatably coupled with another end of the swing arm (53), and urging means (54, 55) for swingingly urging the swing arm (53) so that the tension roller (51) presses the belt (15).

Abstract: An autotensioner comprises a torsion coil spring interposed between a base and a rocking arm, and a tubular bushing provided between an inside surface of the base and an outside surface of the rocking arm. The torsion coil spring pushes and biases the rocking arm toward the bushing, and brings the pushing direction substantially in coincidence with the axial load direction of the force, acting on a stepped bolt supporting the rocking arm, from a belt. When the belt tension becomes high, the arm axial center displaces slightly from the base axial center, an extremely large first damping force acts on the rocking arm. When the belt tension becomes low, the smaller second damping force acts on the rocking arm.

Abstract: In a belt type continuously variable speed system, when a hydraulic cylinder (110) operates, the hydraulic cylinder (110) and an elastic member (134) in a tensioner (104) draw a belt (102) against an elastic member contained in a variable radius pulley (107). Consequently, a power transmission ring contained in the variable radius pulley (107) is made eccentric from the axis of the variable radius pulley. The power transmission ring is displaced to the position where a force produced by the hydraulic cylinder (110) and the elastic member (134) in the tensioner (104) to make the power transmission ring eccentric and a force produced by an elastic member contained in the variable radius pulley (107) to urge the power transmission ring toward a position which is concentric with the axis of the variable radius pulley (107) are balanced with each other, thereby achieving speed variation.

Abstract: A tensioner for a power transmission element of a traction drive, includes a housing, a swivel arm having a free end for connection to a rotatable tension roller which rests on the power transmission element, and a swivel bearing, including an axle for connection to the swivel arm and a bushing forming part of the housing and supporting the axle, for rotatably supporting the swivel arm in the housing. A spring is positioned in a peripheral zone of the swivel bearing between the swivel arm and the housing. Mounted in fixed rotative engagement to the axle and supported by the housing via a friction lining is a friction disk, with a disk-shaped first dampening element positioned between the friction lining and the housing.

Abstract: A tensioner for tensioning engine driven driving elements, such as belts or chains, is disclosed. In accordance with one aspect of the invention, the tensioner is initially installed with the pivot structure spaced past the perpendicular angular position thereof. In accordance with another aspect of the invention, the tension required to move the pivot structure to the end of its range of angular positions is at least 75% more than at the hot engine angular position thereof. In accordance with another aspect of the invention, the tensioner has a stop at the maximum travel position thereof and the tension required to move the pivot structure to its maximum travel position is at least 75% more than at the hot engine angular position thereof. In accordance with a still further aspect of the invention, the tension required to move the pivot structure to a potential tooth skip angular position is greater than the maximum tension the engine is capable of creating.

Abstract: A belt tensioner mounted on mounting structure in normal and reverse modes which comprises a hub structure. An arm structure is pivotally mounted on the hub structure for pivotal movements with respect thereto about a pivot axis central to the hub structure between first and second limiting positions. A belt-engaging pulley is rotatably mounted on the arm structure for rotational movement about a rotational axis parallel with the pivotal axis. A spring system is provided for resiliently biasing the arm structure away from the first limiting position and toward the second limiting position. The hub structure includes a central opening extending axially therethrough configured to allow a mounting bolt to extend therethrough and into secured relation to the mounting structure. The hub structure includes a normal mode mounting plate on one axial end thereof which engages the mounting structure when the mounting bolt is secured therein as aforesaid.

Abstract: The invention comprises a tensioner having an inner race rotation idler pulley. The pulley having a web and a belt bearing surface connected to the web. The web is attached to an inner race of a bearing by a fastener. The pulley may be stamped out of sheet metal or of spun metal and may have a central hole for alignment with the central axis of the bearing. The outer race of the bearing is mounted to a pivot arm. The pivot arm comprises as least two pivot points for pivotably attaching the pivot arm to a mounting plate and a biasing member. The pivot points are contained within a periphery of the pulley. The biasing member urges the pivot arm and pulley against a belt to be tensioned.

Abstract: A belt tensioner for a power transmission belt system includes: (a) a base housing having a pivot shaft extending therefrom; (b) a tension arm pivotally mounted on the pivot shaft at a proximal end thereof, the proximal end of the tension arm including a rub surface and the distal end of the tension arm adapted to contact a power transmission belt; (c) a torsion spring operatively coupled between the base housing and the tension arm and adapted to bias the distal end of the tension arm against the power transmission belt; and (d) a damper assembly coupled to the housing, the damper assembly including: (1) a body of friction material that includes a friction surface adjacent to and facing the rub surface of the tension arm and (2) a damper spring integral with the body of friction material and biasing the body of friction material and associated friction surface against the rub surface of the tension arm.

Abstract: A tensioner comprising a rigid cage provided with a fixing means for fixing to an engine block or to a plate rotatably mounted on the engine block. The cage slidably receives a rigid part that carries, preferably at one of its ends, bearing means for bearing against the belt, which bearing means can be constituted by a wheel. Resilient return means are mounted inside the wheel-supporting part to urge the cage and the part towards a spaced-apart position, the return means being constituted preferably by a helical spring.

Abstract: A tensioner for an endless belt comprising a stationary structure on which a pivotal tension arm with an idler pulley is mounted. A spring between the tension arm and the stationary structure acts to bias the pulley against the belt, thereby applying tension. The invention includes a one-way device that is operable in response to the extent of pivotal movement of the tension arm in the forward direction to establish different positions at which pivotal movement in the return direction is limited. A damping system is used to restrict pivotal movement of the tension arm as a result of sudden short-time vibratory movements or dynamic vibrations in cold conditions.

Abstract: In pressing a slack-side span of a V-ribbed belt, entrained about a crank pulley variable in rotational speed, auxiliary pulleys and an idler pulley, with an auto tensioner, thereby automatically balancing tension of the belt, the damping coefficient DI of the auto tensioner is set in accordance with the modulus of longitudinal elasticity of the belt. For example, when the modulus of longitudinal elasticity of the belt is at least 9800 N/100% rib and less than 29400 N/100% rib, the damping coefficient DI of the auto tensioner is set at at least 20% and less than 100%. In this manner, even if the rate at which the auto tensioner absorbs elongation of the belt is as extremely small as 0.3 to 1.0 mm/deg, a rocking motion of the auto tensioner can be avoided thereby reducing the occurrence of a slip or a frictional sound of the belt and the occurrence of abrasion and frictional sounds of friction members, such as an insert bearing and a thrust washer, of the auto tensioner.

Abstract: A belt tensioner for automatically tightening a belt of a motor vehicle. The belt tensioner includes a tensioner mechanism including a hub, an inner casing and an outer casing. The outer casing is movably mounted to the inner casing. The hub is freely mounted for rotation to the outer casing and for contacting the belt and selectively tightening and loosening the belt in response to movement of the outer casing relative to the inner casing in first and second directions, respectively. The belt tensioner further includes a biasing mechanism for providing a torque force to the outer casing in the first direction. The belt tensioner additionally includes a one-way clutch mechanism normally resisting movement of the outer casing relative to the inner casing in the second direction. An exteriorly accessible rotatably member is associated with the one-way clutch mechanism for selectively deactivating the one-way clutch mechanism to prevent movement of the inner casing in the second direction.