Method for determining the orientation of two shafts connected via two universal joints and a third shaft in the plane of the three shafts

1. Method for aligning a first shaft relative to a second shaft which are connected or which can be connected via two universal joints and a third shaft, using an optoelectronic alignment device which in a first and a second measurement head contains at least one light source for emitting a straight-line or fanned out light beam and at least one detector which can be read out two-dimensionally for receiving the light beam, the first measurement head being mounted on the first shaft and the second measurement head being mounted on the second shaft with a respective clamping device, comprising the following steps:

a) determining a plane in which the first, second and third shafts lie and a first measurement position in the plane of the three shafts,

b) emitting a straight-line or fanned out light beam from said at least one light source and measuring a point or points of impact of the light beam or beams on said least one detector with the measurement heads of the optoelectronic alignment device in a first measurement position,

c) turning the first, second and third shafts and the clamping devices around the first and the second shafts into a second measurement position which is 180° away from the first measurement position, and moving at least one of the first measurement head and second measurement head on the respective clamping device in a radial direction relative to the respective shaft so that at least one light beam strikes at least one detector,

d) measuring a point or points of impact of the light beam or beams with the measurement heads of the laser alignment device in the second measurement position, and

e) determining an angular offset between the first and the second shafts from the measured values of the points of impact.

2. Method in accordance with claim 1 , comprising the further step of correcting the angular alignment of the first and second shafts.

3. Method in accordance with claim 1 , wherein a relative three-dimensional orientation of the first and second measurement position is determined with at least one of at least one inclinometer and a gyroscope in at least one of the measurement heads.

4. Method in accordance with claim 1 , wherein a relative three-dimensional orientation of the first and second measurement position is determined with at least one rotational angle transducer on one of the first and second shafts.

5. Method in accordance with claim 1 , wherein the step determining a plane in which the first, second and third shafts lie comprises emitting a light beam from a light source mounted on of the first and second shaft such that the light beam runs parallel to the respect one of the first and second shaft so as to strike the third shaft, and then, moving the light source into the plane determined by the light source being shifted while maintaining the alignment parallel to the respective shaft, such that the impact point of the light beam on the third shaft is moved to a point nearest the light source along a peripheral line of the third shaft.