Universal joint
A universal joint or cardan joint is a mechanical joint, which connects two non- aligned shafts with each other. The bending angle shall not be changed during torque transmission. The combination of universal joints with a wave is often called a propeller shaft.
History
One of the first accurate traditional applications found in the Clock of Strasbourg Cathedral from 1354, the Caspar Schott reported in 1664. With the name Gerolamo Cardano is since about 1550 later than (mainly in Europe ) " gimbal " designated movable suspension become known, which Cardano himself wrote that he had been inspired by a similar device. Since 1245 Villard de Honnecourt a suspension for a furnace known and in 1500 Leonardo da Vinci hangs in the same way a compass.
The English polymath Robert Hooke invented in 1663 the universal joints in a preform, he has recognized its nonuniform transmission and developed the combination to a double universal joint that compensates for this non-uniformity by combining two single joints for double universal joint. In the English-speaking universal joints are known to this day as " Hooke 's joint ."
Universal joints in its present form with a spider back to Amicus (16th century) and the mathematical proof of the non-uniform rotation Jean Victor Poncelet put 1824 before.
Function and Applications
A central part (cross piece ) contains two perpendicular crossed stub axle pairs, through which it is articulated to each of the two waves: the waves each have a forked end, the cross- holes each include a pair of stub axle. A rarer variant in which one of the two waves is hinged inside the central part, reminiscent of the gimbal ( at the gimbal of a gyroscope ( gyro ) is located innermost in a third wave to the gyro rotates ).
A structural unit of universal joint / s and wave / n is called a propeller shaft. This is used traditionally for torque transmission in motor vehicles between the unit engine / transmission and rear axle. The wave bridge the considerable distance. When resilient movement of the rear axle universal joint (or the universal joints ) undergoes a small diffraction.
In an attached to the tractor driven machine that runs itself, the deflection between the tractor and the machine is relatively high. The PTO on the tractor followed by a double universal joint with intermediate shaft (double cardan shaft ).
Wheel trailer
Wheel trailer for motorcycles and bicycles are usually by means of a universal joint coupled ( left). The two freedoms in this clutch to allow the towing vehicle lateral swinging ( cornering) and the screwing and unscrewing ( lane - change in slope ) of the trailer. In the longitudinal direction of the trailer from the towing vehicle is prevented from falling over the side.
The structure in which the trailer is coupled by means of a fork and twisted off at the rear axle (pictured right) is a special universal joint. The cross piece is the size of this fork, at the rear end of the second - the vertical axis of rotation - is located. The center lines of the two cross-piece - axes do not intersect as usual at one point.
Gimbal
A diffracted universal joint causes a non-uniform rotation transmission. This means that at a constant rotational speed of the drive shaft, the output shaft has not a constant rotational speed. This non-uniformity, which is also called gimbal error increases with the bending angle. The current ratio of the rotational speed and, also referred to as ( current ) translation, wherein an instantaneous angle of rotation of the drive shaft:
Occasionally, the difference in the rotational angle is referred to as a gimbal. The angle of rotation depends according to the following equation of the rotation angle and the bending angle from: