A hydraulic tensioning device for a chain device, having a housing and having a clamping piston guided displaceably in a housing bore of the housing, the clamping piston having a piston cavity with a hardened inner circumferential surface, and also having a pressure relief valve unit arranged in the piston cavity. The pressure relief valve unit (12) is a preassemblable unit and includes a spring (18), a closing body (17) and a valve seat (16) and also a receptacle (15, 26) at least partially enclosing the valve seat (16), wherein the valve seat (16) is made of a metal material, has an at least partially hardened surface and wherein the receptacle (15, 26) forms a press-fit with the inner circumferential surface of the clamping piston (3).

A hydraulic tensioning device for a chain device, having a housing and having a clamping piston guided displaceably in a housing bore of the housing, the clamping piston having a piston cavity with a hardened inner circumferential surface, and also having a pressure relief valve unit arranged in the piston cavity. The pressure relief valve unit (12) is a preassemblable unit and includes a spring (18), a closing body (17) and a valve seat (16) and also a receptacle (15, 26) at least partially enclosing the valve seat (16), wherein the valve seat (16) is made of a metal material, has an at least partially hardened surface and wherein the receptacle (15, 26) forms a press-fit with the inner circumferential surface of the clamping piston (3).

Ring tensioners having a plurality of rungs that extend from a first side to an opposite second side of the ring tensioner, in use, the rungs engaging between the teeth of a toothed belt. Both the first side and the second side of the ring tensioner are not continuous but have gaps. The gaps on the first side alternate with the gaps on the second side. The ring tensioners may be formed from a single length of wire.

Ring tensioners having a plurality of rungs that extend from a first side to an opposite second side of the ring tensioner, in use, the rungs engaging between the teeth of a toothed belt. Both the first side and the second side of the ring tensioner are not continuous but have gaps. The gaps on the first side alternate with the gaps on the second side. The ring tensioners may be formed from a single length of wire.

A variable force tensioning assembly creates and maintains a tension force on an endless loop used to transmit power. The variable force tensioning assembly includes a body having a cylinder defining a cylinder inner diameter. An outer piston is disposed substantially within the cylinder and slidable therewithin. The outer piston includes an outer piston tube and a chamber divider extending through the outer piston tube. The outer piston and the body define a low rate portion. An inner piston is disposed at least partially within the outer piston tube and is slidable therewithin. The inner piston defines a high rate portion and acts with the outer piston against the body to create a variable force to push against the endless loop to maintain a constant tension in the endless loop.

A method of operating a chain drive that includes sprockets. Tensile chain moments on the sprockets are determined and a specification value for operating the chain drive is determined therefrom in an automated manner. A corresponding assembly has a chain drive with sprockets and with a control device at least partly associated with the chain drive. The control device is configured for carrying out the method and a specification value for load distribution among the two drives for operating the chain drive is determined therefrom in an automated manner.

To simplify a structure and reduce costs. A shoe for a chain guide or for a chain tensioner arm is constructed. Here, a shoe (3) has a chain sliding surface (30) on which a chain slides. A locking protrusion such as a clip, a tab or a hook for locking the shoe (3) to a tensioner arm main body (2) of a chain tensioner arm (1) is not provided on an end surface of the shoe (3) or on a surface on the rear side of the chain sliding surface (30). Furthermore, the shoe (3) has a uniform cross-sectional shape over the whole length and extends linearly in the longitudinal direction.

To simplify a structure and reduce costs. A shoe for a chain guide or for a chain tensioner arm is constructed. Here, a shoe (3) has a chain sliding surface (30) on which a chain slides. A locking protrusion such as a clip, a tab or a hook for locking the shoe (3) to a tensioner arm main body (2) of a chain tensioner arm (1) is not provided on an end surface of the shoe (3) or on a surface on the rear side of the chain sliding surface (30). Furthermore, the shoe (3) has a uniform cross-sectional shape over the whole length and extends linearly in the longitudinal direction.

To provide a chain guide assembly frame capable of efficiently collecting the oil that adhered to various parts of the chain guide assembly, and guiding the collected oil to predetermined locations, to allow efficient use of oil, with a simple structure. The chain guide assembly frame includes driven sprocket holding portions, a fixed chain guide, and a pivoting chain guide holding portion on a main body. A drive sprocket holding portion is provided at a position lower than the driven sprocket holding portions. The main body includes a concave and/or convex oil passage that extends from an upper part toward a lower part to guide the oil toward above the drive sprocket holding portion.

To provide a simple-structured chain guide assembly frame capable of reliably maintaining a correct positional relationship between a driven sprocket and a sprocket holding portion without the possibility of driven sprocket detachment. The chain guide assembly frame includes a main body having a fixed-guide-side sprocket holding portion and a pivoting-guide-side sprocket holding portion. The fixed-guide-side sprocket holding portion includes a first fixed-guide-side support portion that supports a driven sprocket at a first contact point, and a second fixed-guide-side support portion that supports the driven sprocket at a second contact point located more outside than the first contact point. When the driven sprocket is in an erected state in which the driven sprocket is supported at the first contact point and second contact point, the vector of gravity acting on the gravity center of the driven sprocket points between the first contact point and second contact point.