 Relationship between Relative Position of Sensor and Pulser and Waveform Distortion Rate |
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- The output waveform is a quasi-sine wave. If the waveform distortion rate is high, division error occurs when the interpolation division number is set to a large value.
- The distortion rate increases when the relative position of the gear and sensor is incorrect.
- In the case of an involute spur gear with a module of 0.4 and 256 teeth (pulser), the relationship between the relative position of the sensor and pulser and waveform distortion is explained.
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| <Relative position of sensor and pulser (gear)> |
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- The waveform distortion rate is calculated according to the amplitude spectrum obtained with an FFT analyzer.
- The waveform distortion rate K (%) indicates the distortion of the measured waveform compared with the ideal sine wave. It can be calculated by finding the amplitude of each discrete frequency.
E1 shows the output voltage amplitude of the fundamental wave.
E2 shows the output voltage amplitude of the secondary higher harmonic wave. (E3: Tertiary, E4: Quaternary, and so forth)
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| 1. Characteristics according to waveform distortion factor |
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| <Typical gap/distortion rate characteristic> |
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| <Typical X-direction dislocation/distortion rate characteristic> |
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| <Typical azimuth-direction dislocation/distortion rate characteristic> |
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- The distortion rate is a maximum of 0.8% when the gap between the sensor and pulser is a minimum of 0.1 mm.
- The above factors greatly distort the waveform in the following order.
Gap > X-direction dislocation  Azimuth-direction dislocation
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