Abstract: A tensioning device has an inner end plate mounted on a frame, a sleeve fixed to the end plate and extending along an axis toward an idler wheel over which is spanned a flexible endless element (e.g. a drive chain or conveyor belt), and an axially compressible stack of inner and outer spring rings. The stack is closely surrounded by the sleeve, forms an annular friction spring, and has one end bearing axially on the plate and an opposite end. An outer end plate bears axially toward the frame end plate on the opposite end of the annular friction spring, and a hydraulic unit is braced axially between the outer end plate and the idler wheel. The inner spring rings have substantially frustoconical outer surfaces and the outer spring rings have substantially frustoconical inner surfaces engaging the outer surfaces of the inner rings.

Abstract: A track system for a track vehicle which has a crawler chain and a driving sprocket wheel. The chain has links each of which has a pin assembly with a bushing or one piece bolt the outer periphery of which at least is composed of a material consisting of Si.sub.3 N.sub.4 silicon nitride or a zirconium oxide with at most 15% of sintering additives. The driving sprocket wheel can have segments formed with the teeth and bolted to a disk, the segments being composed of a material consisting of Si.sub.3 N.sub.4 silicon nitride or zirconium oxide with less than 15% of sintering additives.

Abstract: In order to create a track roller for crawler chains, consisting of a track oller body, an axle traversing the same as well as bearings and seals arranged between the track roller body and the axle, whereby the axle is affixed to a mount with its ends axially protruding from the track roller body, which has a long life when used as intended, the invention proposes that the bearings (3) radially arranged between the track roller body (1) and the axle (2) be designed as pivoting bearings, so that the load-caused bending of the track roller body or the axle can follow without jamming.

Abstract: A drive system, especially a belt drive for a multi-axial vehicle running gear, has a drive drum about which the belt is looped and provided with a ring with entrainers which engage teeth on the belt when there is slip between the belt and the drum. Limited rotation of the ring relative to the drum may be effected by elliptical spring elements coupling the ring and the drum or by clutches on the drum which frequently lock the ring to the drum so as to effect control engagement of the entrainers with the belt teeth and positive drive of the belt by the drum.

Abstract: A rotatable drive/support element having a support surface is used with a chain link having a hardened running surface extending in and adapted to ride in a travel direction on the support surface and a side surface also extending in the travel direction and normally out of contact with the element. The running surface has a predetermined width b and is formed of at least one edge region of an outwardly convex arcuate shape seen in the travel direction having a radius R of curvature and a respective corner region extending from the edge region to the side region and of an outwardly convex arcuate shape seen in the travel direction having a radius r of curvature. Herein r/b.congruent.0.05 to 0.11, and preferably R/b.congruent.2.4 to 3.1.

Abstract: A track-chain link has a pin extending along and defining an axis and having a pair of ends and a radially outwardly directed cylindrical outer surface and a bushing coaxially surrounding the pin and having ends set axially inward of the pin ends and forming axially oppositely outwardly directed end surfaces. Structure on each of the pin ends defines an axially inwardly directed end surface axially confronting the respective bushing end surface and a radially inwardly directed inner surface radially confronting the pin outer surface and defining with the pin outer surface, the bushing end surface, and the structure end surface an annular compartment filled with a body of a liquid lubricant.

Abstract: Sealing arrangement including an elongated bolt formed with a unilaterally open bore, a bushing coaxial with the bolt and spaced radially outwardly therefrom to form an annular passage between the bolt and bushing, the bushing being integrally provided with opposite support end surfaces, a pair of outer chain link mounted on the bolt and the bushing and forming respective opposite spacers with the respective support surfaces of the bushing, each of the spacers being provided with respective lubricating channels formed in the bushing and communicating with the annular channel for conveying a lubricant from the channel into the spacers and a pair of annular seals each received in the respective spacer.