The invention relates to a tensioner (100) comprising: a hollow body (10) provided with a bottom (12), said bottom comprising a central zone (120), a peripheral zone (121) raised relative to the central zone and an intermediate zone (122) an axis (30) two guide means (40, 50) for said axis two cups (60, 124), the cup (124) comprising a first portion (124A) in front of the peripheral zone and a second portion (124B) in front of the intermediate zone a spring (70) held between the cups and arranged around the second guide means so that there is a gap between the spring and the second guide means a valve (80) with a channel (90), the channel opening in front of the second portion of the cup (124) away from said second portion.

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 tensioner that has a reduced number of components and weight, and is easy to assemble. The tensioner has a base member loosely fitted into an open rear end of a cylindrical plunger with a closed front end against the resiliency of a biasing means accommodated inside the plunger. The tensioner includes a plunger stopper mechanism configured such that an engaging part formed on the base member detachably engages an engaging groove provided on an inner circumferential surface of the plunger directly or via another member.

A hydraulic tensioner for an internal combustion engine for tensioning a span of a chain or a belt has a piston with an internal reservoir connected to a high pressure chamber through a check valve assembly. The check valve assembly has a disk seat formed by an internal bulge within the piston; a check valve retainer within the piston, and a moveable disk that is received between the disk seat formed by the internal bulge and the check valve retainer and is moveable between a first position and a second position, and a check valve spring that is received between the check valve disk and the check valve retainer.

An object of the present invention is to provide a tensioner that enables a sufficient amount of stroke for the plunger to be secured and allows for size and weight reductions without changing the size of the tensioner body. In the tensioner according to the invention, an oil supply path that supplies oil from outside to an oil reservoir chamber formed inside the plunger includes an oil supply space formed between an inner circumferential surface of the plunger bore and an outer circumferential surface of the plunger. The oil supply space is formed by a front-end communication groove formed on an inner circumferential surface of the plunger bore and communicating with a tensioner body oil supply hole, and a rear-end communication groove formed on an outer circumferential surface of the plunger and causing the front-end communication groove to communicate with a plunger oil supply hole.

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.

A tensioner assembly for tensioning a belt including a moveable arm, a first tensioner pulley mounted to the moveable arm, and a second tensioner pulley mounted to the moveable arm. In a first position of the moveable arm corresponding to a forward drive configuration, the first tensioner pulley is positioned in contact with the belt while the second tensioner pulley is spaced apart from the belt. In a second position of the moveable arm corresponding to a reverse drive configuration, the second tensioner pulley is positioned in contact with the belt while the first tensioner pulley is spaced apart from the belt.

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.

An articulated chain with alternating inner chain links and outer chain links which are each connected to each other by means of a chain joint, wherein each outer chain link comprises at least two outer link plates and two chain studs connecting them to each other, each inner chain link comprises at least two inner link plates and two joint sleeves connecting them to each other, and for forming a chain joint, one chain stud each of the outer chain link extends through a joint sleeve of the inner chain link. The joint sleeves of the inner chain links are embodied as winding sleeves and firmly connected to the inner link plates, wherein the sleeve joints of the two winding sleeves are positioned on the same side of a link plate's longitudinal axis and face each other, and the sleeve joints are arranged at a distance to the link plate's longitudinal axis and at a distance to an upper apex or to a lower inflection point of the winding sleeve.

To provide a tensioner capable of keeping oil pressure in an oil pressure chamber stable with a simple structure. The tensioner is equipped with a pressure adjusting mechanism that adjusts oil pressure in the oil pressure chamber and includes an adjustment space formed in a housing and communicating with the oil pressure chamber, a movable member disposed such as to be movable to and from the oil pressure chamber, and a pressure adjusting biasing unit that biases the movable member toward the oil pressure chamber. A liquid tight seal is maintained between the movable member and an inner wall of the adjustment space, between a position where the movable member has moved closest to the oil pressure chamber and a position where the movable member is farthest from the oil pressure chamber.