To provide a tensioner unit, a rocking lever, and a tensioner, which, prevent breakage of the tensioner in use for a prolonged period of time. A protruding part is provided to a rocking lever near an abutment surface for abutment with a plunger to make contact with a tensioner body. h and H satisfy the relationship of h<H, where h denotes a protruding amount of a lead part of the plunger, where the lead part means a part protruding from the plunger bore, from a tip end surface on an opened side of the tensioner body in a state where the plunger sits on a bottom of the plunger bore, and H denotes an interval between the abutment surface of the rocking lever and the tip end surface of the tensioner body when the protruding part is brought into contact with the tensioner body.

To provide a tensioner unit, a rocking lever, and a tensioner, which, prevent breakage of the tensioner in use for a prolonged period of time. A protruding part is provided to a rocking lever near an abutment surface for abutment with a plunger to make contact with a tensioner body. h and H satisfy the relationship of h<H, where h denotes a protruding amount of a lead part of the plunger, where the lead part means a part protruding from the plunger bore, from a tip end surface on an opened side of the tensioner body in a state where the plunger sits on a bottom of the plunger bore, and H denotes an interval between the abutment surface of the rocking lever and the tip end surface of the tensioner body when the protruding part is brought into contact with the tensioner body.

A hydraulic tensioner (10) and method of assembly can include a housing (12) having an aperture and a piston (16) received within the aperture for movement between an extended position and a retracted position. A tensioner spring (36) positioned within the aperture for bias the piston (16) toward the extended position. The piston (16) and the aperture of the housing (12) defining an expandable fluid chamber (18). The hydraulic tensioner (10) can include a cantilever spring (20) having a first end (22) attachable to the housing (12) and a second end (24) releasably engageable with the piston (16) for retaining the piston (16) in the retracted position against urging of the tensioner spring (36) during storage, shipment, installation, and service. The second end (24) can be disengageable from the piston (16) allowing movement of the piston (16) outwardly toward the extended position during operation in a working environment.

Provided is a chain guide that enables a reduction in size with a simple structure, without lowering the strength of the chain guide. The base member 30 includes a side wall rib 32 or 33 extending upward higher than a shoe support surface 31 at at least one of both side edges 31a and 31b in a guide width direction. The guide shoe 20 includes, at at least one of both side edges 20a and 20b in the guide width direction, an upstream lip 22, a downstream lip 23, and a shoe widthwise recess 24 formed between the upstream lip 22 and the downstream lip 23 by inwardly recessing the side edge 20a or 20b of the guide shoe 20 in the guide width direction. The side wall rib 32 or 33 is located inside the shoe widthwise recess 24.

Provided is a chain guide that enables a reduction in size with a simple structure, without lowering the strength of the chain guide. The base member 30 includes a side wall rib 32 or 33 extending upward higher than a shoe support surface 31 at at least one of both side edges 31a and 31b in a guide width direction. The guide shoe 20 includes, at at least one of both side edges 20a and 20b in the guide width direction, an upstream lip 22, a downstream lip 23, and a shoe widthwise recess 24 formed between the upstream lip 22 and the downstream lip 23 by inwardly recessing the side edge 20a or 20b of the guide shoe 20 in the guide width direction. The side wall rib 32 or 33 is located inside the shoe widthwise recess 24.

Tensioner systems, methods and apparatus are described for tensioning drive belts of vibratory screens.

A compliant tensioner arm assembly including an arm, an elastically deformable body disposed on a surface of the arm, and a sliding surface disposed on the elastically deformable body is disclosed. The elastically deformable body allows the sliding surface to yield to a load condition of the sliding surface so that the sliding surface yields to the load condition.

A compliant tensioner arm assembly including an arm, an elastically deformable body disposed on a surface of the arm, and a sliding surface disposed on the elastically deformable body is disclosed. The elastically deformable body allows the sliding surface to yield to a load condition of the sliding surface so that the sliding surface yields to the load condition.

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.

A hydraulic tensioner (10) and method of manufacture can include a housing (12), a piston (16) moveable from a retracted position toward an extended position with respect to the housing (12) in response to fluid pressure, and a tensioner spring (36) biasing the piston (16) toward the extended position. The hydraulic tensioner (10) can include a modular sleeve (14) supported by the housing (12) and defining an aperture (15) for slidably receiving the piston (16) and defining an expandable fluid chamber (18). The housing (12) can provide a fluid passage (39) for fluid communication between the expandable fluid chamber (18) and a source of pressurized fluid. The housing (12) can have a seat (25) in fluid communication with the aperture (15). An end (38) of the modular sleeve (14) can be seated with respect to a seat (25) of the housing (12) to seal the fluid passage (39).