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: An object of the present invention is to provide a tensioner and a rocking lever that have simple configurations and that enable an increase in the volume of a space provided inside a plunger, the tensioner and the rocking lever being capable of preventing a stopper pin from being damaged or falling out. A plunger pin hole 121 is formed in a plunger 120 of a tensioner 100. In a tensioner body 110, a body pin hole 113 is formed in a tip protruding portion 112 provided so as to protrude from a side of an opening of the plunger housing hole 121. One of lips 154 provided on opposite sides, in a width direction, of the pressing surface 153 of a rocking lever 150 so as to protrude from the pressing surface 153, has a thinned portion 155 thinned in the width direction.

Abstract: Provided is a tensioner which can ensure, with a simple structure, both the stability of the installation state of a check valve and the capacity of an oil storage chamber. A tensioner has a plunger, a housing, a check valve, and a coil spring. The plunger has a front-side plunger part having a pressing front end portion, and a rear-side plunger part disposed on the rear side of the front-side plunger part and having a valve movement restricting portion. The check valve is disposed on the rear side of the valve movement restricting portion. The coil spring is disposed so that one end thereof is in contact with a housing bottom portion and the other end thereof is in contact with the rear side of the check valve.

Abstract: To provide a tensioner which can circulate a sufficient amount of oil even if there is a long time lag until pressurized oil starts to be supplied, and which exhibits a lower level of leak of oil stored therein, and which is structured simply without increasing the number of components therefore. The tensioner includes: a tensioner body having a plunger bore; a cylindrical plunger slidably inserted into the plunger bore; and biasing means for urging the plunger outward. When the tensioner is fixed to a wall surface, a body hole that extends from the wall surface up to a circumferential surface of the plunger bore is located lower than an oil discharge hole in the wall surface.

Abstract: An object of the present invention is to provide a chain tensioner which enables operations on an elastic ring member during assembly and maintenance work to be readily performed and which is capable of eliminating protrusion of an operating portion of the elastic ring member in a direction opposite to a mounting surface, with a simple configuration. A ring holding portion 112 provided on an open side of a plunger housing hole 111 includes a pressing projection 113 and a restricting portion 114 which restrict rotation of the elastic ring member 130 and which oppose both outer sides of a pair of operating portions 132 of the elastic ring member 130 in a circumferential direction, and the pressing projection 113 is arranged at a position closer to a mounting surface 115 than the restricting portion 114.

Abstract: Provided is a chain tensioner that can improve the degree of freedom in setting the oil supply position with a simple structure, can supply sufficient and necessary oil when restarted after a long time after the stop of oil supply, can entirely be made shorter and smaller, and can be produced easily with reduced cost. In a chain tensioner 100 in which a plunger 120 inserted in a plunger bore 111 of a tensioner body 110 is biased outward by biasing means 140 provided in an oil pressure chamber 101 to be extendable and contractible, an oil reservoir chamber 123 is formed on an outer side than a check valve 150 inside a plunger body 126, and a connection/adjustment groove 103 forming an oil supply space 102 is formed in an inner circumferential surface of the plunger bore 111.

Abstract: Provided is a chain tensioner that is capable of restricting the movement of a plunger at an engagement position, hardly causes its breakage and abrasion even if receiving a great force applied to the plunger, needs no setting for a backlash amount, and allows the engagement position of the plunger to be freely shifted forward and backward. The tensioner body has an engagement member that extends toward and retracts from engagement grooves provided on the outer periphery of the plunger, a press member that presses, in one direction, a cam member which maintains and releases the extending state of the engagement member, and a hydraulic supply path through which oil is supplied to press the cam member in a direction opposite to the pressing direction of the press member.

Abstract: To provide a chain tensioner capable of constantly applying an appropriate pressing force under any situations including high-speed, high-load operation, at the start of an engine, and normal range operation, without an increase in size or amount of oil consumption. A check valve unit 150 is disposed between an oil pressure chamber 101 and an oil supply part 103. A second oil pressure chamber 102 is formed between an outer circumferential surface of a plunger 120 and a cylindrical surface 113 of a plunger bore 111, into which oil leaking from the oil pressure chamber 101 flows and whose volume increases as the plunger 120 retracts. Further provided is a relief valve unit 130 that releases oil when the pressure of the second oil pressure chamber 102 reaches or exceeds a predetermined high level.

Abstract: To provide a chain tensioner capable of constantly providing an appropriate reaction force and damping characteristics for a variety of tension fluctuations irrespective of chain elongation, and capable of accommodating the tension fluctuations. The chain tensioner includes a distal end plunger 130 slidably inserted in a distal end bore 121 of a plunger 120, and a distal end biasing means 141 accommodated inside a second oil pressure chamber 102 such as to be able to expand and contract and to urge the distal end plunger 130. The chain tensioner further includes a check valve unit 150 that stops oil flowing from an oil pressure chamber 101 into the second oil pressure chamber 102, and a first relief valve unit 160 that releases oil toward the oil pressure chamber 101 when the pressure reaches or exceeds a predetermined high level.

Abstract: The chain guide mechanism includes a slack side guide, a tension side guide, and a link member that is capable of rotating about a predetermined rotary shaft provided so as to be fixed to an attachment subject. The link member includes a slack side pivot portion attached rotatably to the slack side guide, and the slack side pivot portion is disposed on an opposite side of the chain that is guided by the slack side guide to the predetermined rotary shaft, and in a lower position than the predetermined rotary shaft. The slack side guide is biased by its own weight toward a side of the chain that is guided by the slack side guide.

Abstract: To provide a chain tensioner that can maintain the pressure of the oil pressure chamber at a correct level to achieve a desired reaction force and damping characteristics corresponding to the rpm, and enable a reduction in the number of parts to be machined and the number of assembling steps; reduce the amount of oil flowing out of the system; and prevent damage to the check valve, without causing an increase in size of the chain tensioner. The chain tensioner includes a check valve unit 150 that stops reverse flow of oil flowing into an oil pressure chamber 101, and a first relief valve unit 160 and a second relief valve unit 170 that release oil when the pressure reaches or exceeds a predetermined high level. The second relief valve unit 170 has a higher valve opening pressure than that of the first relief valve unit 160.

Abstract: The present invention provides a highly durable chain guide which is simply configured, easy to assemble, and low in material cost, and in which vibration and tilting are suppressed, enabling reductions in noise, wear, breakage, and so on. A guide shoe includes a plate housing portion which is formed on a rear surface side of a travel guiding portion, and into which a plate can be inserted from below, and in at least one location of an attachment portion or a tensioner contact portion, the plate housing portion constitutes a plate end holding portion formed to be capable of supporting an end portion of the plate from below such that the plate can be inserted therein from a direction other than from below.

Abstract: Provided is a chain tensioner that can, with a simple structure, supply sufficient and necessary oil when restarted after a long time after the stop of oil supply, and control pressing force in accordance with operating conditions during the drive, thereby reducing vibration of the chain not only when restarted but also during the drive. In a chain tensioner 100 in which a plunger 120 inserted in a plunger bore of a tensioner body 110 is biased outward by biasing means 140 provided in an oil pressure chamber 101 to be extendable and contractible, an oil supply hole 114, an oil supply space 102, and a plunger hole 124 that together form a continuous oil supply passage is formed in such a shape that an oil amount changes in accordance with a position of the plunger 120.

Abstract: The occupation space of a chain inside an engine room can be reduced, while the necessary strength, rigidity, and durability are maintained, the sheet thickness can be decreased, the number of production steps and material waste can be reduced, stress concentration and strains during bending and fixing can be reduced, load offset during fixing and loosening of bolts or the like can be prevented, the increase in vibrations and noise during the use can be prevented, the maintenance operation load can be reduced, and utility can be increased with a simple configuration. A chain guide is provided with a base member supporting a guide shoe. The base member has a base mounting portion and base wall portions formed to sandwich the guide shoe from both sides in a width direction. The guide shoe has a guide shoe mounting portion at a position apart from the base mounting portion in the chain running direction.

Abstract: To provide a simple design chain tensioner that enables formation with fewer components and simplifies assembling process, and is capable of driving a chain stably, thereby reducing wear or occurrence of breakage and improve durability. The chain tensioner 100 includes a chain-drive guide shoe 130 pivotally supported on an arm 120 provided to a tensioner body 110. A bushing part 140 of the chain-drive guide shoe 130 includes a mating hole 141 to mate with a first pin portion 122 that extends from the distal end of the arm 120 to one lateral side, and a guide part 142 guided by a part of a second pin portion 123 that extends to the other lateral side, and a slit 143 wider than a portion of the arm 120 facing the chain-drive guide shoe 130 is provided between the mating hole 141 and the guide part 142.

Abstract: A chain transmission is provided which is capable of reducing friction loss in the transmission of power without the risk of compromising the durability of a chain guide mechanism and the chain. The chain transmission includes a chain and a chain guide mechanism. The chain guide mechanism includes a first guide and a second guide having a smaller radius of curvature than that of the first guide. The plurality of plates include a first plate and a second plate. The first plate has a backside height set such that the first plate does not contact the first guide when the first plate is guided by the first guide and such that the first plate contacts the second guide when the first plate is guided by the second guide.

Abstract: To provide a chain tensioner and a relief valve unit that enable a reduction in the number of parts to be machined and the number of assembling steps, reduce the amount of oil flowing out to the outside, and prevent damage on a check valve, without having to increase the size of the chain tensioner. The chain tensioner includes a check valve unit that suppresses reverse flow of oil flowing into an oil pressure chamber, and a relief valve unit that releases the oil when the pressure inside the oil pressure chamber reaches or exceeds a predetermined high pressure. The check valve unit is disposed as a valve element of the relief valve unit, and the relief valve unit and the check valve unit are formed integral with each other.

Abstract: An object of the present invention is to provide a chain tensioner that allows a necessary and sufficient amount of oil to be fed during restart following a long stoppage of oil feeding and that maintains a proper pressure, thus preventing possible noise and vibration. An oil storing chamber 123 is formed inside a plunger 120 and forward of a check valve 150 in a protruding direction of the plunger 120. A tensioner body 110 has an oil feeding hole 114 through which a cylindrical surface portion 113 of a plunger housing hole 111 communicates with an outside and a high-pressure discharge hole 115 through which a pressure oil chamber 101 in the plunger housing hole 111 communicates with the outside. A relief valve 160 that is opened under a high pressure is provided in the high-pressure discharge hole 115 and closer to the pressure oil chamber 101.

Abstract: An object of the present invention is to provide a tensioner and a rocking lever that have simple configurations and that enable an increase in the volume of a space provided inside a plunger, the tensioner and the rocking lever being capable of preventing a stopper pin from being damaged or falling out. A plunger pin hole 121 is formed in a plunger 120 of a tensioner 100. In a tensioner body 110, a body pin hole 113 is formed in a tip protruding portion 112 provided so as to protrude from a side of an opening of the plunger housing hole 121. One of lips 154 provided on opposite sides, in a width direction, of the pressing surface 153 of a rocking lever 150 so as to protrude from the pressing surface 153, has a thinned portion 155 thinned in the width direction.

Abstract: To provide a tensioner which can circulate a sufficient amount of oil even if there is a long time lag until pressurized oil starts to be supplied, and which exhibits a lower level of leak of oil stored therein, and which is structured simply without increasing the number of components therefore. The tensioner includes: a tensioner body having a plunger bore; a cylindrical plunger slidably inserted into the plunger bore; and biasing means for urging the plunger outward. When the tensioner is fixed to a wall surface, a body hole that extends from the wall surface up to a circumferential surface of the plunger bore is located lower than an oil discharge hole in the wall surface.