A belt tensioning device for a crusher or a screening machine for tensioning at least one circulating drive belt which is deflected about a belt pulley of a drive and has a load strand and an empty strand. The drive can be driven with a crushing assembly, a screening unit, a generator, or the like of the crusher by the drive belt. The vibrational stress acting on the machine chassis can be significantly reduced in that the belt tensioning device has two tensioning rollers each of which is rotatably mounted on a holder of a tensioning part. One tensioning roller is paired with the empty strand and the other is paired with the load strand. Additionally, the two tensioning parts can be adjusted relative to each other between an open position and a tensioning position, in which the tensioning parts are held against each other at least opposite the tensioning direction. In particular the tensioning parts can be blocked against each other, and the complete closed system can be freely moved linearly using adjustment guides according to the load situation.

A blind having a blind operating mechanism and a blind control element and having an enclosure for the blind control element, with the element completely enclosed, a connector supporting the enclosure on the blind, and depending downwardly, and an opening disposed by the enclosure to permit access to the blind control element, and a closure to permit access to the opening in one position and bar access to the opening in a second position.

An engine system includes a frame, a prime mover, and drive-belt system. The prime mover is coupled with the frame for movement therewith. The drive-belt system includes a wheel configured to be driven by the prime mover about a rotation axis and to transmit energy to an accessory unit.

A chain tensioner is formed with internal threads each including a push-in-side flank, a protruding-side flank , and a thread top face. The push-in-side flank has a flank angle larger than the flank angle of the protruding-side flank. The push-in-side flank and the protruding-side flank are rolled surfaces formed by rolling, and have a surface roughness smaller than Ra 1.0 μm. Each internal thread further includes, at its position at which the protruding-side flank intersects with the thread top face, a chamfer configured to receive a bulge moving from the protruding-side flank during rolling.

A position of a reservoir hole of a hollow piston of a hydraulic tensioner is downside of a centerline or center plane of the piston to increase the oil retention within the internal reservoir during engine shutdown, reduce start up noise and decrease air from accumulating within the internal reservoir.

Provided is a tensioner capable of reducing a machining or mounting load and preventing leakage of oil from a surface for mounting a tensioner with a simple configuration. A tension body having a plunger-receiving hole into which a plunger is slidably inserted is configured to have a projection portion on a mounting surface that face a wall surface having an oil discharge hole of amounting target object. The projection portion is configured to be inserted into the oil discharge hole and to be continuously connected to the oil supply path formed in the tensioner body to form an oil passage.

A coupling system can include an energy transfer device and a load mitigation system. The energy transfer device can include a shaft, gear, chain or piston-cylinder arrangement to transfer the energy from a power supply to an object to be moved. The load mitigation system can be used to limit or prevent the transfer of forces from the object to the drive unit as a result of external loads being applied to the object. The load mitigation system can be pre-loaded such that external loads on the object having an excessive impulsive or resonant cyclic force greater than the pre-load force on the load mitigation system are reduced and only partially transferred to the energy transfer device and power supply. The load mitigation system can dampen both resonant loads and impulsive impact loads occurring at the object thereby preventing damage and extending life.

A mower drive belt tensioner arm includes an elongate body having a tension pulley to provide tension to a mower drive belt. One of a pair of rear draft towers on the mower deck supports the elongate body above the surface of the mower deck. A coil spring urges an end of the elongate body in a direction between the pair of draft towers. A pivotable belt keeper may be mounted to the tensioner arm without tools, and extends over the perimeter of the tension pulley.

The invention relates to a belt-tensioning device comprising a tensioning device for generating a force for tensioning a belt in a belt drive; a measuring device for measuring a belt tension or a measurement variable corresponding to the belt tension; and an adjustment device for adjusting the force generated by the tensioning device based on signals of the measuring device.

A manual drive assembly for a manually-operated window treatment based on a drive chain formed as a loop, may incorporate one or more intermediate tensioners disposed between two ends of the loop. The loop may be formed between a manual clutch mechanism coupled to the window treatment and an end tensioner. The one or more intermediate tensioners may serve to limit slack in the loop such that sides of the loop cannot be pulled to create a large loop, for example, having a gap of four inches or greater, between the hanging sides of the cord.