A method for measuring the rotation angle of a rotating shaft to suppress the rotation error of the shafting inclination angle

Abstract

The invention belongs to the field of optical measurement, and is a method for measuring the rotation angle of a rotating shaft that can suppress the influence of the inclination angle rotation error of a shaft system. The measurement principle system of the present invention is shown in FIG. 1 , the rotating shaft 2 with the optical wedge 5 is placed between the autocollimator 1 and the reflector 3 . Due to the refraction effect of the optical wedge 5, the beam emitted by the autocollimator 1 is reflected by the reflector 3, forms a deflection angle β with the outgoing beam, returns to the autocollimator 1, and converges into a light point image; when the rotating shaft 2 and the light When the wedge 5 rotates integrally, the reflected light beam rotates around the axis of the rotating shaft 2, and the light spot image in the autocollimator 1 moves along a circular trajectory; the computer 4 records the centroid coordinates of the light spot image on the circumference, and fits the trajectory circle The coordinates of the center of the circle, and then specify the starting point A and the end point B on the circumference, and use the coordinate values ​​of A and B to calculate the corresponding circle center opening angle, which is the rotation angle of the rotation axis 2 to be measured from A to B. In the present invention, the rotation error of the inclination angle of the shaft system hardly affects the measurement accuracy of the rotation angle.

Description

technical field [0001] The invention belongs to the field of optical-mechanical detection, and is a high-precision method for measuring the rotation angle of a rotating shaft. The invention relates to a combination of an autocollimator, an optical wedge and a reflector, specifically a method for measuring the rotational angle of a rotating shaft that suppresses the rotational error of the inclination angle of the shaft system. Background technique [0002] According to the angle measurement principle of the autocollimator, it is easy to think of using figure 1 The optical path system shown is used to measure the rotation angle of the rotating shaft. Among them, 1 is an autocollimator, 2 is a rotating shaft, 3 is a mirror, and 4 is a computer; the mirror 3 is installed on the end face of the rotating shaft 2, and forms an angle θ with the end face of the rotating shaft 2; After the light beam is reflected by the reflector 3, it is deflected at an angle β=2θ relative to the ...

AI Technical Summary

Problems solved by technology

However, due to the machining error of the shaft, the installation error of the bearing, the clearance of the bearing itself, and the transmission force of the shaft during use, the swing occurs during the rotation of the shaft, which is professionally called the shaft system inclination rotation. The error, which causes the reflected light beam on the mirror 3 to swing, causes the light point image in the autocollimator 1 to deviate from the ideal circular track, and the deviation is twice the error of the axis tilt angle rotation, so that the end position changes from B point change to point B1, such as figure 2 As shown in the The inclination angle rotation error of the shaft system in different rotating mechanisms is different, generally ranging from a few arc seconds to tens of arc seconds

It can be seen that the inclination angle rotation error of the shaft system seriously affects the measurement accuracy of the rotation angle of the shaft 2

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