Described herein is a tensioner device, and assemblies and methods of manufacture thereof. The tensioner device may be adapted to create a target tension in an associated belt based on the measured length of the belt. The tensioner device may include an engagement member having a surface adapted to engage the belt and a biasing element associated with the engagement member. The biasing element has a loaded configuration that causes the engagement member to exert a force on the belt to create the target tension. In one example, the biasing element is manipulated into a loaded configuration so that the biasing element exhibits a deflection and an effective spring rate for creating the target tension. The belt may be trapped within the tensioner device with a bracket assembly enclosing one or more runs of belt relative to the engagement member.

Described herein is a tensioner device, and assemblies and methods of manufacture thereof. The tensioner device may be adapted to create a target tension in an associated belt based on the measured length of the belt and/or measure characteristics of a biasing element, such as a stiffness of the biasing element. A biasing element may exhibit a measured stiffness and be associated with a damping assembly and a base of the tensioner device. An engagement member may be associated with the damping assembly for movement therewith and angularly displaceable relative to the base and the biasing element to tension the belt. In one example, the biasing element may be connected to the damping assembly at a position determined by the measured stiffness to define a value of the angular displacement of the engagement member relative to the biasing element and create a target tension in the belt.

A walk-behind tractor has an increased ground clearance to define a plant receiving space that has a greater height than a conventional walk-behind tractor having a straight axle. The walk-behind tractor has trailing drop arms from a frame that carry wheel axles that result in an elevated height of a driveshaft. The elevated driveshaft increases the ground clearance for taller plants to pass therebeneath during operation of the walk-behind tractor which would otherwise be too tall to pass below a conventional straight axle walk-behind tractor.

A tensioning system including a base and an arm pivotally coupled to the base, the arm having an engagement surface and being configured to pivot relative to the base about a pivot axis. The system further includes a biasing mechanism operatively coupled to the arm to bias the arm relative to the base, and a seal assembly sealingly positioned between the arm and the base. The seal assembly is coaxial with the pivot axis and configured to accommodate relative axial movement between the base and the arm and relative radial movement between the base and the arm while still maintaining a seal therebetween.

A tensioner comprising a base having a base aperture, the base aperture disposed to receive a driven component, a rotary arm pivotally engaged with the base, an axis of rotation of the rotary arm aligned with a base aperture center, a first pulley journalled to the rotary arm, a swing arm pivotally engaged with the rotary arm about a shaft, the shaft and swing arm each having cooperating frustoconical portions, a torsion spring biasing the pivot arm, a second pulley journalled to the swing arm, a bushing having a frustoconical portion in frictional engagement with the swing arm frustoconical portion, the bushing in fixed relation to the shaft or pivot arm, and a first damping ring frictionally engaged between the rotary arm and the base, a Belleville spring in pressing engagement whereby a normal force is applied to the first damping ring.

A tensioner comprising a base, a shaft press fit into the base, a pivot arm journalled to the shaft, the pivot arm having a first frustoconical portion and a frustoconical bushing disposed thereon, a pulley journalled to the pivot arm, a torsion spring engaged between the base and the pivot arm for biasing the pivot arm, a seal disposed between the base and pivot arm on the shaft, the shaft comprising a second frustoconical portion describing an apex angle Δ, and the torsion spring applying an axial spring force to the pivot arm such that the first frustoconical portion is in pressing engagement with the second frustoconical portion.

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.

A dynamic belt-tensioning apparatus for a treadmill includes a base having a first end and a second end spaced from the first end. A foot-striking platform is movably supported by the base so as to allow for vertical movement of the platform during operation of the treadmill. A drive belt has a fixed circumference and is positioned above a top portion of the platform. A drive roller is pivotally mounted adjacent to the first end of the base and engages the drive belt. A bell crank is pivotally coupled to the platform such that pivoting of the bell crank translates into movement of a tensioning roller that is pivotally mounted to the base and that is capable of a range of movement to provide substantially constant tension to the drive belt in response to vertical movement of the platform.

A pulley device configured to support a belt of a chain tensioning idler or runner roller includes a bearing having a rotatable outer ring and a coaxial fixed inner ring and a pulley having at least one C-shaped pulley part that has an inner portion with an inner surface mounted on an outer cylindrical surface of the bearing outer ring, an outer cylindrical portion having an outer cylindrical surface configured to contact the belt or the chain, and a radial intermediate portion between axial outer ends of the inner and outer cylindrical portions and an axial outer end of the outer cylindrical portion, wherein a ratio between a radial material thickness of the outer cylindrical portion and a radial material thickness of the inner cylindrical portion is strictly greater than 1.

In an embodiment, a tensioning apparatus includes a housing and a fastener extending at least partially through the housing. The apparatus also includes a trolley adjustably positioned within the housing about the fastener. The apparatus also includes a pulley disposed outside the housing and coupled to the trolley, where the pulley moves in unison with the trolley along an opening in the housing.