Abstract: A chain guide is provided which has a simple structure and improved durability, and which enables reduction in weight and in material cost, and moreover which does not inhibit smooth flow of resin inside a metal mold, and with which dimension errors, contour errors, internal distortion, defects and the like are reduced and concentration of internal stresses or repeatedly applied bending stresses can be prevented. A reinforcing rib of a body part includes a lateral rib that has an independent zone not connected to other parts of the reinforcing rib over a length of 20% or more of a distance between support portions at two locations of the rib. The independent zone is provided on a side further away from a guide surface than a midpoint of the height of the support wall.

Abstract: A tensioner with a simple structure is provided, which is capable of keeping oil pressure in a first high oil-pressure chamber stable and holding a chain favorably. The tensioner includes a plunger, a housing, a check valve, an inner sleeve, and a biasing member. In the housing, a second high oil-pressure chamber and a unit setting part are formed. In the unit setting part, a relief valve unit is set. A gap between an inner circumferential surface of a plunger hole and an outer circumferential surface of the inner sleeve functions as part of an oil flow passage that connects the first high oil-pressure chamber and the second high oil-pressure chamber.

Abstract: 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.

Abstract: A chain guide is provided which has a simple structure and improved durability, and which enables reduction in weight and in material cost, and moreover which does not inhibit smooth flow of resin inside a metal mold, and with which dimension errors, contour errors, internal distortion, defects and the like are reduced and concentration of internal stresses or repeatedly applied bending stresses can be prevented. A reinforcing rib of a body part includes a lateral rib that has an independent zone not connected to other parts of the reinforcing rib over a length of 20% or more of a distance between support portions at two locations of the rib. The independent zone is provided on a side further away from a guide surface than a midpoint of the height of the support wall.

Abstract: A tensioner with a simple structure is provided, which is capable of keeping oil pressure in a first high oil-pressure chamber stable and holding a chain favorably. The tensioner includes a plunger, a housing, a check valve, an inner sleeve, and a biasing member. In the housing, a second high oil-pressure chamber and a unit setting part are formed. In the unit setting part, a relief valve unit is set. A gap between an inner circumferential surface of a plunger hole and an outer circumferential surface of the inner sleeve functions as part of an oil flow passage that connects the first high oil-pressure chamber and the second high oil-pressure chamber.

Abstract: 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.

Abstract: Provided is a tensioner in which the durability of the tensioner body is increased, the tensioner body is reduced in weight, and the arrangement space is reduced. A tensioner 100 includes a tensioner body 110, a plunger 120, and a ratchet 130. The tensioner body 110 has a hole outer circumferential wall 112 and a pair of pin support walls 116, 117. The hole outer circumferential wall 112 has a pair of outer circumferential wall portions 113, 114 crossing a virtual line L extending in the pin longitudinal direction through the center of the plunger housing hole 111. At least one of the outer side surfaces of the pair of pin support walls 116, 117 is formed on the inner side, in the pin longitudinal direction, of the outer side surface of one of the outer circumferential wall portions 113, 114.

Abstract: Provided is a tensioner in which the durability of the tensioner body is increased, the tensioner body is reduced in weight, and the arrangement space is reduced. A tensioner 100 includes a tensioner body 110, a plunger 120, and a ratchet 130. The tensioner body 110 has a hole outer circumferential wall 112 and a pair of pin support walls 116, 117. The hole outer circumferential wall 112 has a pair of outer circumferential wall portions 113, 114 crossing a virtual line L extending in the pin longitudinal direction through the center of the plunger housing hole 111. At least one of the outer side surfaces of the pair of pin support walls 116, 117 is formed on the inner side, in the pin longitudinal direction, of the outer side surface of one of the outer circumferential wall portions 113, 114.

Abstract: In a silent chain transmission, a silent chain composed of uniform link plates meshes with a sprocket having two or three kinds of teeth randomly distributed around its circumference. The teeth have a common tooth gap bottom diameter, and a uniform angular spacing, but have different heights and different tooth forms.

Abstract: In silent chain transmission comprising a chain composed of rows of link plates connected in articulating relationship by connecting pins, at least one sprocket is provided with a pair of flanges that guide the chain by engaging sprocket-engaging teeth on the outermost plates of the chain.

Abstract: In a double-sided engagement silent chain having inner link plates with inwardly protruding teeth, outermost link plates with outwardly protruding teeth, and outer link plates with outwardly protruding teeth, adjacent the outermost link plates, the plates are composed of a bainite and martensite mixed plate material. The bainite mixing ratio in the outermost link plates is higher than the bainite mixing ratio of the inner link plates and the adjacent outer link plates. The martensite mixing ratio of the inner link plates and of the adjacent outer link plates is higher than the martensite mixing ratio in the outermost link plates. The heights of the backs of the outermost link plates, measured from the tooth gap bottoms, are greater than the corresponding heights of the backs of the inner link plates, and may be equal to or greater than the heights of the backs of the adjacent outer tooth plates.

Abstract: A silent chain with bushings comprises outer and inner links interconnected in alternating relationship. Each outer link comprises outer plates and connecting pins press-fit into the pin holes in the outer plates. Each inner link comprises a center guide plate disposed at a location midway between the sides of the chain, and toothed inner link plates on both sides of the center guide plate. Bushings are press-fit into bushing holes in the guide plate and the toothed inner link plates. The connecting pins of the outer links extend through bushings of the adjacent inner links, thereby connecting the outer and inner links of the chain are in alternating relationship.

Abstract: Link plates of a silent chain are produced by first shaving the inner surfaces of the connecting pin holes, the sprocket tooth-engaging surfaces, and the backs of the link plates, and then forming dimples on those surfaces by shot-peening.

Abstract: In a silent chain, a link plate is formed by punching, followed by simultaneous shearing of the inner surfaces of the pin holes, the inner engagement surfaces of the teeth, the outer engagement surfaces of the teeth, the connecting arc continuous with the inner connecting surfaces, and the back of the link plate over at least 70% of the plate thickness. The plates are arranged at random to form a link, and engage a sprocket first by engagement of an inner engagement surface with a sprocket tooth, and thereafter seat on the sprocket with outer engagement surfaces of the link teeth in engagement with the sprocket teeth.

Abstract: In a double-sided engagement type silent chain in the form of an endless loop, the outermost link plates of the link rows whose outermost plates are not fixed to the chain's connecting pins, have teeth protruding toward the outside of the loon, and are paired in side-by-side relationship with adjacent inner link plates whose teeth protrude toward the inside of the loop.

Abstract: In a double-sided silent chain, the backs of the outermost link plates, which have their teeth protruding in one direction, are higher than the backs of the inner link plates, which have their teeth protruding in the opposite direction. The backs of the outer link plates adjacent the outermost link plates may also be higher than the backs of the inner link plates, and are preferably equal to the heights of the backs of the outermost link plates. The outermost link plates and their adjacent outer link plates are preferably of the outer tooth contact/outer tooth seating type.

Abstract: In a silent chain transmission, a silent chain composed of uniform link plates meshes with a sprocket having two or three kinds of teeth randomly distributed around its circumference. The teeth have a common tooth gap bottom diameter, and a uniform angular spacing, but have different heights and different tooth forms.

Abstract: In a double-sided engagement silent chain having inner link plates with inwardly protruding teeth, outermost link plates with outwardly protruding teeth, and outer link plates with outwardly protruding teeth, adjacent the outermost link plates, the plates are composed of a bainite and martensite mixed plate material. The bainite mixing ratio in the outermost link plates is higher than the bainite mixing ratio of the inner link plates and the adjacent outer link plates. The martensite mixing ratio of the inner link plates and of the adjacent outer link plates is higher than the martensite mixing ratio in the outermost link plates. The heights of the backs of the outermost link plates, measured from the tooth gap bottoms, are greater than the corresponding heights of the backs of the inner link plates, and may be equal to or greater than the heights of the backs of the adjacent outer tooth plates.

Abstract: In a double-sided engagement type silent chain, the backs of the outermost link plates are made higher than those of the inner link plates, and the inner circumferential surfaces of the outer link plates located adjacent the outermost link plates are provided with a metallic carbide coating and formed in the shape of a Japanese “tsuzumi” hand drum.

Abstract: Link plates of a silent chain are produced by first shaving the inner surfaces of the connecting pin holes, the sprocket tooth-engaging surfaces, and the backs of the link plates, and then forming dimples on those surfaces by shot-peening.