The rotary electrical machine comprises, in front, a pulley (3) secured to a shaft (9) of a rotor (20) passing through the front bearing (1a) of a housing. The bearing includes a base, having a nose (18) for mounting a front ball bearing (7) for rotating the shaft (9), and air inlets (15) defined by arms belonging to an outwardly opening area connecting a peripheral strip of material from the base to the nose (18) in order to shift the nose (18) toward the front in accordance with the central body of a device (100) for adjusting the tension of a belt received in the groove (31) of the pulley (3) and attached onto the housing (1a, 1b). The adjustment device (100) comprises at least one idler (200, 201) for tensioning the belt and a central opening (102) enabling passage of air through the air inlets (15).

A method for operating a belt-driven starter generator of an internal combustion engine, in which a time interval between an onset of a rotary motion of the belt-driven starter generator and an onset of a rotary motion of the internal combustion engine is determined, the determined time interval is compared to a reference value, and the structural change of a belt of the belt-driven starter generator is inferred therefrom, and a torque of the belt-driven starter generator and/or a torque of a component connected to the belt is restricted as a function of the structural change of the belt.

A belt drive for driving a rotatably mounted object, includes a main part, at least two belt wheels, a device for generating a pretensioning force, and a continuously circulating belt which loops around the belt wheels. The first belt wheel is connected to or can be connected to a drive, and the second belt wheel is connected to or can be connected to the object. The invention is characterized in that the device has at least two rollers which are attached to opposite sides of a lever that is pivotally mounted on the main part, and each roller contacts a section of the belt, wherein the lever is acted upon by at least one spring element and can be moved relative to the main part.

In an aspect, a tensioner is provided for tensioning an endless drive member that is engaged with a rotary drive member on a shaft of a motive device. The tensioner includes a base that is mountable to the motive device, a ring that is rotatably supported by the base in surrounding relationship with the shaft of the motive device and which is rotatable about a ring axis, a tensioner arm pivotally mounted to the ring for pivotal movement about an arm pivot axis, and first and second tensioner pulleys. The first tensioner pulley is rotatably mounted to the tensioner arm. The tensioner arm is biased towards a first span of the endless drive member on one side of the rotary drive member. The second tensioner pulley is rotatably mounted at least indirectly to the ring and is biased towards a second span of the endless drive member on another side of the rotary drive member. The ring is rotatable in response to hub loads in the first and second tensioner pulleys that result from engagement with the first and second spans of the endless drive member.

Some belt-driven integrated-starter generators (BISGs) have twin-arm tensioners mounted directly to the BISG. Because the distance between the tensioner and the BISG pulley is quite short, any stack up tolerance leads to relatively high misalignment, which, in turn, leads to belt wear and noise. To minimize misalignment, a process is disclosed to machine the tensioner pulley bearing seats on the tensioner arms after assembly to the BISG. The BISG pulley is rotated with three probes recording the axial position change of the BISG pulley over a complete revolution. These data are used to establish a best-fit plane and the tensioner pulley bearing seats are machined to match the best-fit plane so that during operation belt twisting and shifting are minimized.

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.

A chain drive for an internal combustion engine comprises a driving sprocket and at least one driven sprocket, a drive chain coupling the sprockets to each other, and at least one guide rail and/or one tensioning rail for guiding and/or tensioning the drive chain. At least the guide rail and/or the tensioning rail comprises at least two slide elements, arranged at a non-guided distance from one another for contacting the drive chain, such that at least two slide elements are arranged in at least one span of the chain drive. In at least one span, the ratio of guided chain length to non-guided chain length is smaller than 1. Such a chain drive is to be improved with respect to its vibration characteristics. To this end, the sum of the two non-guided lengths of the drive chain between a slide element and the respective nearest sprocket is, in at least one span, which is in contact with a guide rail and/or a tensioning rail with at least two slide elements arranged at a non-guided distance from one another, smaller than 0.5 times the total length of the respective span.

An overhead-cam internal combustion engine includes a crankshaft, a drive wheel rotatable by the crankshaft, a cylinder head, a driven wheel rotatable by the drive wheel, and a camshaft provided within the cylinder head, the camshaft being rotatable by the driven wheel. A flexible drive member extends around the drive wheel and the driven wheel such that power from the crankshaft for rotating the camshaft is transmitted through the flexible drive member. A pair of guide members are positioned to guide a path of the flexible drive member that increases an amount of peripheral wrap of the flexible drive member about the driven wheel. The guide members have co-facing inboard guide surfaces that partially define the path. A tensioner is positioned between the co-facing inboard guide surfaces, and the tensioner is operable to exert a pulling force that increases tension in the flexible drive member during operation.

The present disclosure discloses a tension device for a drive chain of a handrail system of an escalator system, a method and an escalator system including the same. The tension device for the drive chain applies pressures in opposite directions to a drive chain so as to make portions of the drive close to each other to tension the drive chain. The pressures are applied to the drive chain via a weight or a pre-loaded spring. The present disclosure also provides a method for tensioning a drive chain. The present disclosure can eliminate loosening of the drive chain after running several months, eliminate periodic heavy work on site for the escalator system and a drive system comprising the drive chain, and improve quality thereof in a simple, reliable and low cost manner.

A method for ascertaining an accuracy of a torque transmitted by a belt-driven starter generator of an internal combustion engine to the internal combustion engine, the method being similar to a learning operation or a calibration of the actual torque of the starter generator with respect to a setpoint torque, includes: in an idling instance of the internal combustion engine, controlling the belt-driven starter generator to transmit a specified test torque to the internal combustion engine and decreasing the torque of the internal combustion engine by the specified test torque; determining and evaluating a speed variable, which is a function of a speed of the internal combustion engine; and deducing the torque accuracy from the evaluated speed variable.