A belt tension control system may include a first belt engager to engage a first portion of a belt extending between and on a first side of first and second pulleys and a second belt engager to engage a second portion of the belt extending between and on a second side of the first and second pulleys. The first belt engager is movably supported so as to move in response to changes in tension of the first portion of the belt. The second belt engager is movably supported so as to move in response to changes in tension of the second portion of the belt. The first belt engager and the second belt engager are connected by a linkage such that movement of the first belt engager towards the first portion of the belt automatically retracts the second belt engager away from the second portion of the belt, wherein the linkage automatically maintains a constant ratio of belt tension of the first portion to belt tension of the second portion.

Provided is a tensioner which has a small total number of components and no risk of incorrect assembly, allows easy load change, is easy to assemble, and excellently stabilizes an oil pressure in a pressure oil chamber. The tensioner 100 includes a relief mechanism that relieves oil to the outside of a plunger 110 when the oil pressure in the pressure oil chamber formed between the plunger 110 and a plunger containing hole 121 in a housing 120 increases, relief holes 141 extending through the plunger 120 from the inside of a plunger inner space 111 to an outer circumferential side thereof, and a hole closing member 142 that is pressed into an opening of each of the relief holes 141 on the outer circumferential side.

The belt drive assembly includes a frame having a first plate including an inner surface, an outer surface, a first end, and a second end, a second plate including an inner surface, an outer surface, a first end, and a second end, and a shaft disposed between the first plate and the second plate. The belt drive assembly also includes a first pair of idler pulley wheels positioned coaxially at one end of the first plate, a second pair of idler pulley wheels positioned coaxially at one end of the second plate, a drive pulley wheel rotatably mounted onto the outer surface of the first plate, a driven pulley wheel rotatably mounted onto the outer surface of the second plate, and an endless belt trained on the drive pulley wheel, on each idler pulley wheel, and on the driven pulley wheel.

A hydraulic traction mechanism tensioner for a traction mechanism drive of a motor vehicle, having a housing, a tensioning piston which is mounted within the housing such that it can be displaced in the axial direction and encloses a hydraulic pressure chamber with the housing, and a valve which has an actuating element and is inserted in a fluid supply channel of the housing, wherein the valve hydraulically connects a first channel section of the fluid supply channel which opens into the pressure chamber to a hydraulic supply in a first position of the actuating element, and disconnects the first channel section from the hydraulic supply in a second position of the actuating element, wherein the valve is configured as a pressure regulating valve, wherein the actuating element can be moved beyond the second position into at least one further, third position, with the result that a volume of the first channel section is increased in comparison with the second position.

A hydraulic auto-tensioner is provided which includes a cylinder, a valve sleeve, a rod, a spring seat, and a plunger slidably fitted on the outer diameter surface of the rod. A first leakage gap is defined between the fitting surfaces of the plunger and the rod. A second leakage gap is defined between the fitting surfaces of the plunger and the valve sleeve such that the resistance to oil flowing in the second leakage gap is larger than the resistance to oil flowing in the first leakage gap. With the engine running normally, when the tension of the belt increases, and thus a pushing force is applied to the hydraulic auto-tensioner such that the cylinder and the spring seat are pushed toward each other, oil in a pressure chamber leaks through the first leakage gap into a reservoir chamber.

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.

An electrical starter system and construction kit for retrofitting Harley-Davidson motorcycles built from 1936 to 1957 with a mechanical starting device. The starter system includes a clutch device that can be coupled to the transmission main shaft for transmitting rotary motion having at least one starter gearwheel, a clutch hub, a clutch cage that can be or is attached to the hub for transmitting a rotary motion and an electrical starter motor with a starter shaft pinion that can be driven by the electrical motor for engaging the starter gearwheel. The starter gearwheel is or can be mechanically coupled to the clutch hub for transmitting a rotary motion to the hub. Preferably, a gearwheel/hub adapter is disposed between and couples the clutch hub and the starter gearwheel. The adapter is or can be coupled to the starter gearwheel and the clutch hub and is or can be coupled to a transmission main shaft of the motorcycle.

A tensioner which adjusts the mean tensioner force to keep the chain tension as low as possible without sacrificing chain control, significantly improving drive efficiency as the chain wears and is subject to low dynamic loads.

In one embodiment, a fluid delivery system includes a motor assembly and a fluid pump assembly. The fluid pump assembly is spaced apart from the motor assembly, and at least one of the motor assembly or the fluid pump assembly is movable to change a distance between the motor assembly and the fluid pump assembly. The fluid delivery system includes a flexible linkage that couples the motor assembly to the fluid pump assembly, and is configured to transfer motion from the motor assembly to the fluid pump assembly. Further, the fluid delivery system comprises a linkage tightening mechanism configured to generate a tightening force on the linkage by biasing at least one of the motor assembly or the fluid pump assembly in a direction that increases the distance between the motor assembly and the fluid pump assembly.

In one embodiment, the present invention relates to a belt tensioning device for a hollow blind that comprises: a holder seat equipped with a lower belt gear on the top portion of the holder, the holder seat is in clearance fit with a lumen of a side frame of the hollow blind and is provided with a group of V-shaped slots from top to bottom therein, each V-shaped slot is equipped with a clip therein, the slip has a width slightly larger than the width of the lumen of the side frame of the hollow blind when being bent. The present invention allows the belt tensioning device to move along a single direction within the side frame of the hollow blind so that the distance between two belt gears can be gradually adjusted, thereby maintaining a proper tensioning force in the belt.