To provide a tensioner capable of preventing slipping between a rack portion and ratchet pawls and securing a large backlash with a simple structure. The tensioner includes a ratchet rotatably mounted on a housing and having a front pawl and a rear pawl spaced apart in a front and rear direction on a side face positioned opposite the rack portion. The ratchet includes an additional pawl formed between the front pawl and the rear pawl in the front and rear direction on the side face positioned opposite the rack portion.

An object of the present invention is to provide a chain guide that can reduce vibration and noise while maintaining necessary strength, rigidity, and durability. The chain guide has a support wall extending forward from a boss part, which constitutes a circumferential wall of a pivot shaft, along a plane perpendicular to a pivot axis line. The support wall includes a base part that is provided with a running surface-side rib, and a connecting portion with a cross-sectional area thereof reducing toward the boss part. The running surface-side rib is not in contact with the boss part. The chain guide does not include a connecting portion that has a larger width than the thickness of the support wall and extends in a pivoting direction on a back side of the running surface-side rib in a region at a pivot shaft side end thereof.

An object of the present invention is to provide a chain guide mechanism that can readily integrate all the components in a simple structure and enhance work efficiency during assembly or maintenance. The chain guide mechanism of the present invention is configured to be able to integrally support, on a frame, components including a plurality of sprockets, a chain, a fixed chain guide, and a pivoting chain guide. The frame includes a pivoting chain guide holding part that holds a mounting boss of the pivoting chain guide in a state of a loose fit. The pivoting chain guide holding part is configured to allow the mounting boss to be fitted therethrough from one side.

To provide a simple-structured tensioner lever capable of consistently exerting a correct reaction force to various fluctuations of tension accompanying varying chain behaviors, whereby vibration and noise when the chain runs can be reduced. The tensioner lever of the present invention includes a lever body having a shoe surface that slidably guides a chain; a first pressing spring configured to have a first pressing arm extending from one end of a first helical part, with a distal end portion contacting the lever body to form a first loading point, and a first support arm extending from the other end of the first helical part, with a distal end portion contacting and being supported by a first support part provided to an attachment surface to form a first support point; and a second pressing spring supported on the lever body at a different position from that of the first pressing spring.

An object of the present invention is to provide a chain tensioner that can prevent breakage or deformation of its components during transport or storage, prevent wrong assembly, and increase the degree of design freedom. The chain tensioner includes a guide lever supported pivotably on an arm part that is provided to a tensioner body. The tensioner body has a body-side fixing pin hole positioned for a stopper pin to pass through without extending through the plunger. The guide lever has a lever-side fixing pin hole that comes to be coaxial with the body-side fixing pin hole in a predetermined pivoting position.

A damper device for a wrap-around means of a wrap-around transmission includes a carrier body formed from a composite reinforced plastic and comprising a surface, a sliding surface forming a first part of the surface, and a bearing surface for a pivoting means, the bearing surface forming a second part of the surface. The sliding surface or the bearing surface may be formed from a separate layer free of composite reinforcing means. The separate layer may be produced as a step of a multi component injection molding method with the carrier body being produced in a common injection mold in another step, as a coating on the carrier body, or as a separate component mechanically connected to the carrier body.

A vehicle includes a chain tensioner that serves as an oil damper using oil supplied from an oil pump. The vehicle includes a controller that controls a traveling mode of the vehicle in a BEV mode or a non-BEV mode. When shifting the traveling mode from the BEV mode to the non-BEV mode, the controller executes a high-pressure process for calculating a supply pressure of oil supplied to the chain tensioner that is higher when a duration of the BEV mode is greater than or equal to a specified time than when the BEV mode duration is less than the specified time.

To provide a chain guide, chain drive device, and transmission system, with which an amount of lubricating oil supplied to guide surfaces is increased. The chain guide includes an upper additional extension formed to extend from an upper end of a sliding guide part in the guide longitudinal direction and having an oil-recovery guide surface positioned opposite and spaced from the chain.

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 which is larger than a 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 a position at which the protruding-side flank intersects with the thread top face, a chamfer configured to receive a bulge resulting from excess materials pushed out from the protruding-side flank during formation of the internal thread by rolling.

To provide a chain guide that can improve transportability and assembly operation efficiency, while also ensuring stable running of a timing chain and enhancing durability, with a simple structure. The chain guide has a guide shoe that slidably guides a chain, and a chain guide body that supports the guide shoe. A compression limiter having an attachment hole through which a mounting bolt for attaching the chain guide to an attachment target member passes is fitted in a fixing through hole extending through the chain guide body in a width direction thereof. A compression limiter holding mechanism is provided either to the compression limiter or to a hole rim part including the fixing through hole of the chain guide body in order to hold the compression limiter.