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While rotating, the universal joint has a sinuslike, fluctuating angular speed depending on the deflection angle. As described in detail in the chapter ,,General fundamental theory", this system-linked fault can be offset for a driving line equipped with two or more joints by choosing special joint arrangements.
When dimensioning the drive or the auxlliarv drive, the following rules must be observed in practice:
Angle conditions of the universal shaft
1. Shaft with two joints
"Z-arrangement" 
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"W-arrangement" 
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The deflection angles of the joints must be equal:
= 
This rule is also applicable to front view and top view pictures.
The joint yokes of the connecting shaft must be in one plane.
All three shafts must be in one plane.
Note: All these three rules must be observed simultaneously.
A joint arrangement in two planes must be avoided if possible. lt is always given when the driving and driven shafts are not in the same plane. If this arrangement is unavoidable and rigid on the installation side, this ,,fault" can be kinematically compensated by a joint misalignment.
Front view:  
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Top view:  
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For the resulting deflection angles the following equations are applicable:
2. Shaft with three joints
In cases where greater distances between units have to be bridged, the universal shaft must be supported by an additional, mostly elastic, bearing.
In order to keep the remaining irregularity in the drive (joint 3) as small as possible, the sum of all irregulanties of the individualjoints must be equal to or almost equal to zero.
(See "Kinematics of Hooke's joints")
The signs must be entered according to the following sign rule. Here the sign rule is:
for the joint position
for the joint position
The remaining non-uniformity if any should not be greater than:
erfolgen.
The equivalent deflection angle
= 3° is the equivalent
deflection angle of a single joint which corresponds with a
degree of non-uniformity U = 0,0027.
3. Shafts with several joints
In case of an arrangement with more than three joints proceed as described above.
General recommendations for lorry drives:
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For fast-running drive shafts observe the instructions on the transverse
whirling speeds for installation length.
(See "Influence of speed and deflection angle") |
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Choose small resulting deflection angles for the main drive range: (See also (n x ß)perm. "Influence of speed and deflection angle") |
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Minimize the angular difference between the joints
and the remaining inequaltity
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If these recommendations are not observed, one must reckon with vibrations and noises and with a reduced driving comfort as well as with a reduced lifetime of the units.
Deflection of joints in two planes
If a "classic shaft arrangement" cannot be realized and the joint deflection cannot be changed, this can be offset by turning the joints. For this shaft arrangement the Installation rule that the resulting deflections of the joints must be equal remains in force, i.e.
which is offset by
turning the joints correspondingly.
The torsion angle
is determined as follows:
The rotation direction results ifom the side view, i.e. joint 1 must be turned to plane 1 by the angle
.
The shaft must be mounted according to these statements and this before a possible balancing. This position of the joints must be marked with arrows.
     
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