Abstract: A bush (1, 19) for a bush chain (15), the inner surface (4) of which bush has a friction surface for a pin (12), wherein the inner surface (4) has two sections (4, 5, 21, 22), which lie opposite each other and extend in the longitudinal direction of the bush (1, 19) and are asymmetrically curved.

Abstract: A chain element (2), in particular a chain pin (4), for joining at least two chain links (3), characterized in that it comprises a surface layer (5) containing boron and vanadium, formed by at least one step of diffusing boron and vanadium in the areas of the chain element (2) which are close to the surface. The surface layer (5) containing boron and vanadium is formed by boriding and subsequently vanadizing a substrate material having a carbon content of 0.60 wt.-% to 1.0 wt.-%.

Abstract: A bush (1, 19) for a bush chain (15), the inner surface (4) of which bush has a friction surface for a pin (12), wherein the inner surface (4) has two sections (4, 5, 21, 22), which lie opposite each other and extend in the longitudinal direction of the bush (1, 19) and are asymmetrically curved.

Abstract: Chain element (2), particularly a chain pin (4) for joining at least two chain links (3), which element is formed from a base material (5) containing carbon, particularly steel, characterized in that it has a surface layer (7) containing boron and vanadium, wherein the surface layer (7) is produced by a method according to which, in a first method step, an intermediate layer (6) containing carbon and vanadium is formed by at least one measure for the diffusion of vanadium into surface regions close to the surface of the base material (5) and, in a subsequent second method step, the surface layer (7) is formed by the transformation of the intermediate layer (6) by at least one measure for the diffusion of boron into the intermediate layer (6).

Abstract: A chain element (2), in particular a chain pin (4), for joining at least two chain links (3), characterized in that it comprises a surface layer (5) containing boron and vanadium, formed by at least one step of diffusing boron and vanadium in the areas of the chain element (2) which are close to the surface. The surface layer (5) containing boron and vanadium is formed by boriding and subsequently vanadizing a substrate material having a carbon content of 0.60 wt.-% to 1.0 wt.-%.

Abstract: A chain element (2), in particular a chain pin (4), for joining at least two chain links (3), characterized in that it comprises a surface layer (5) containing boron and vanadium, formed by at least one step of diffusing boron and vanadium in the areas of the chain element (2) which are close to the surface. The surface layer (5) containing boron and vanadium is formed by borizing and subsequently vanadizing.

Abstract: Chain element (2), particularly a chain pin (4) for joining at least two chain links (3), which element is formed from a base material (5) containing carbon, particularly steel, characterized in that it has a surface layer (7) containing boron and vanadium, wherein the surface layer (7) is produced by a method according to which, in a first method step, an intermediate layer (6) containing carbon and vanadium is formed by at least one measure for the diffusion of vanadium into surface regions close to the surface of the base material (5) and, in a subsequent second method step, the surface layer (7) is formed by the transformation of the intermediate layer (6) by at least one measure for the diffusion of boron into the intermediate layer (6).

Abstract: The invention relates to a chain guide plate, more particularly a chain guide side plate, having a contour profile (1) which has at least one contour profile section (3) of concave configuration and at least one contour profile section (7) of convex configuration situated opposite the contour profile section (3) of concave configuration. An area (22) formed by the contour profile section (7) of convex configuration can be arranged within an area (21) formed by the contour profile section (3) of concave configuration.

Abstract: A chain is disclosed having pins, each having a first end and a second end, and first and second outer plates press-fitted around the first and second ends of each of the pins, respectively. Each of the first and second outer plates has two pin holes through which the first and second ends of respective ones of the pins extend, respectively. First and second inner link assemblies, each consisting of at least one toothed inner plate, are disposed between the first and second outer plates. The at least one toothed inner plate has two openings each having a respective bushing press-fitted therein and arranged around respective ones of the pins with a slip-fit. Toothed middle plates, each having two pin holes press-fitted around respective ones of the pins, are disposed between the first and second inner link assemblies.

Abstract: The chain tensioner has a housing with a first part that defines a bore which receives a second part that is tubular. The second part has a bore which receives a plunger. A check valve is disposed in the housing for controlling the delivery of a hydraulic fluid into the bore of the housing. A fluid passage is defined between the first and second part as a helical groove on the outside of the second part. The passage has an inlet for communication with a source of hydraulic fluid provided from, for example, an engine pump and an outlet that is in fluid communication with the check valve. The arrangement enables the check valve to be offset from the point where fluid is supplied to the tensioner thereby enabling the tensioner to be designed in a more compact configuration.

Abstract: A chain or belt tensioner comprises a plunger displaceable in a bore of a housing between retracted and extended positions. The plunger and the bore between them define a variable volume chamber for receipt of pressurised hydraulic fluid. The tensioner is designed for insertion into a supporting bore of the cylinder head of an internal combustion engine such that the plunger has only a limited number of possible orientations so that it can engage with the tensioner arm. The plunger has an air purge passage that extends from adjacent to the chamber to atmosphere. The passage formation is designed so that there is a portion of it adjacent to the chamber is uppermost in any orientation of the plunger so as to ensure rapid and effective air purging. There may be a single air purge passage extending in an axial direction along the length of the plunger or a combination of several axial and circumferential portions that permit the plunger to be disposed in more than one orientation.

Abstract: A chain or belt tensioner comprises a plunger displaceable in a bore of a housing between retracted and extended positions. The plunger and the bore between them define a variable volume chamber for receipt of pressurised hydraulic fluid. The tensioner is designed for insertion into a supporting bore of the cylinder head of an internal combustion engine such that the plunger has only a limited number of possible orientations so that it can engage with the tensioner arm. The plunger has an air purge passage that extends from adjacent to the chamber to atmosphere. The passage formation is designed so that there is a portion of it adjacent to the chamber is uppermost in any orientation of the plunger so as to ensure rapid and effective air purging. There may be a single air purge passage extending in an axial direction along the length of the plunger or a combination of several axial and circumferential portions that permit the plunger to be disposed in more than one orientation.

Abstract: A chain or belt tensioner comprises a plunger displaceable in a housing between retracted and extended positions. A stop ring between the plunger and housing frictionally contacts a smooth surface of the housing. A recess in the plunger has a tapered face for engagement with a bevelled surface of the stop ring. Inward movement of the plunger causes the tapered face to engage the stop ring and to force it to deform outwardly to a wedging position in which the stop ring is wedged between the tapered face and the surface thus preventing further inward movement of the plunger. The recess has a second face that engages the stop ring when the plunger moves out of the housing so as to slide it over the surface. The invention provides for a stop mechanism that enables retraction of the plunger to be prevented at an infinite number of positions.

Abstract: A chain drive assembly for an internal combustion engine comprises a chain tensioner (6) that acts upon a chain (2) that is used to drive the cam shafts (4) of the engine. The tensioner has a hydraulically actuated plunger (30) which is moveable within a housing and biasing means in the form of a solenoid (34), compression spring or motor that urges the plunger outwards of the housing at least when there is no hydraulic pressure. The tensioner is controlled by means of a control unit (8) that receives signals from various transducers that transmit signals providing information in relation to the performance of the engine. The control unit receives the measured information, calculates the desired tension to be applied to the chain and transmits the control signal to the chain tensioner so as to operate the biasing means or control the hydraulic pressure so that the desired chain tension is applied.

Abstract: A belt or chain tensioner comprises a plunger that is slidably received in a chamber of the tensioner housing. The plunger is biased by a spring to project out of the housing and into contact with a tensioning shoe by which tension is applied to the chain or belt. The chamber is supplied with hydraulic fluid to damp movement of the plunger within the housing. The spring is captively connected between the plunger and housing and located outside of the housing. The tensioner is simple to install and remove from an internal combustion engine as the plunger and housing are held together by the spring.

Abstract: A chain drive comprises a chain having a plurality of articulating chain links and a toothed sprocket. The sprocket and the chain links have bearing surfaces that contact one another during meshing of the chain. The surfaces are disposed along the length of the chain between the apertures and to one side of a sprocket tooth. One of the bearing surfaces is arcuate so that during meshing of said chain link the bearing surfaces are brought into contact such that the instantaneous centre of rotation of the meshing chain link passes from the first pivot pin of a link to the point of contact of the bearing surfaces before passing to the second pivot pin of the link. This reduces the noise generated by collision of the chain links and the sprocket teeth.

Abstract: The link plates, bushes or rollers of a transmission chain are treated so as to produce a surface layer of iron bisulphide. The surface improves the resistance of the chain to wear and also accelerates the running-in process.

Abstract: A chain drive comprises a chain having a plurality of articulating chain links and a toothed sprocket. The sprocket and the chain links have bearing surfaces that contact one another during meshing of the chain. The surfaces are disposed along the length of the chain between the apertures and to one side of a sprocket tooth. One of the bearing surfaces is arcuate so that during meshing of said chain link the bearing surfaces are brought into contact such that the instantaneous centre of rotation of the meshing chain link passes from the first pivot pin of a link to the point of contact of the bearing surfaces before passing to the second pivot pin of the link. This reduces the noise generated by collision of the chain links and the sprocket teeth.

Abstract: A chain or belt tensioner comprises a plunger displaceable in a bore of a housing between retracted and extended positions. A radially resilient stop ring disposed in the bore between the plunger and housing is engaged in frictional contact with a smooth surface of the housing. A recess in the plunger is defined opposite the smooth bore and has a tapered face for engagement with a bevelled surface of the stop ring. The tapered face tapers radially inwardly in the direction towards the open end of the bore so that movement of the plunger relative to the housing towards the retracted position causes the tapered face to engage said surface of the stop ring and to force it to deform in a radial direction to a wedging position in which the stop ring is wedged between the tapered face and the bore surface so as to prevent further inward movement of the plunger.

Abstract: The link plates, bushes or rollers of a transmission chain are treated so as to produce a surface layer of iron bisulphide. The surface improves the resistance of the chain to wear and also accelerates the running-in process.