Installation and Maintenance

Load on connection bearings The bearings of the driving and the driven shafts are strained by statle and dynamic forces and moments. These bearing forces result from: Static bad due to the weight of the universal shaft the length compensation under torque the torque deviation in case of deflected universal shafts Dynamic bad due to the remaining unbalance of the shafts the aperiodical length compensation (axle movement) under torque the torque deviation in case of rotating, deflected shafts and centrifugal forces in case of untrue running of the connected units Bearing forces due to torque deviation The torque equation for a deflected joint is: (See "General fundamental theory ") If the transmitted power (N) is taken as constant (no friction losses), the torque relation can also be es follows: The extremes of the transmission i are: Thus also: Bearing forces due to Iengh alteration With a constant drive capacity resp. with a constant drive torque and a constant angular drive velocity an irregular torque behaviour is obtained in the drive. Since the torque is only transmitted in the journal cross plane, the cross, however, has a horizontal position with regard to the drive shaft at one moment and a vertical position with regard to the driven shaft at another moment, depending on the position of the yoke, there is, in the former case, a bending torque on the yoke of the driven shaft and, in the latter case, a bending torque on the yoke of the driving shaft. Thus the driven torque fluctuates twice per rotation between the extreme values / cos ß and * cos ß = 0°; 180° = 90°; 270° The universal shaft with two joints in the Z-arrangement shown is Ioaded with the following moments. Here, as for the single joint, only the two extreme positions are shown. = 90°; 270° = = 0°; 180° = In general: Radial forces on connecting bearings For universal shafts with two joints mounted normally while observing the installation instructions it is usually enough to know the greatest reaction forces in the bearings of the driving and driven shafts, which occur two times per rotation. The following calculation scheme may be helpful. (See "Calculation scheme") Axial forces on connecting bearings Axial forces on connecting bearings are encountered in the form of reaction forces due to: displacement of the engine / transmission and / or transfer box units axle displacements These axial forces are a function of: the amounts of torque to be transmitted the sectional dimensions of Ion gitudinal compensating elements the friction coefficient in Ion gitudinal compensating elements the deflection angles of the cardan shaft under operating conditions the relative dynamic displacement of engine and transmission units additional loads due to hydraulic effects arising when the grease chamber in the Ion gitudinal displacement system is filled beyond capacity