Methods and systems for measuring an axial position of a rotating component of an engine are described herein. The method comprises obtaining a signal from a sensor coupled to the rotating component, the rotating component having a plurality of position markers distributed about a surface thereof, the position markers having an axially varying characteristic configured to cause a change in a varying parameter of the signal as a function of the axial position of the rotating component. Based on the signal, the method comprises determining a rotational speed of the rotating component from the signal, determining the varying parameter of the signal, and finding the axial position of the rotating component based on a known relationship between the axial position, the rotational speed, and the varying parameter of the signal.

Methods and systems for measuring an axial position of a rotating component of an engine are described herein. The method comprises obtaining a signal from a sensor coupled to the rotating component, the rotating component having a plurality of position markers distributed about a surface thereof, the position markers having an axially varying characteristic configured to cause a change in a varying parameter of the signal as a function of the axial position of the rotating component. Based on the signal, the method comprises determining a rotational speed of the rotating component from the signal, determining the varying parameter of the signal, and finding the axial position of the rotating component based on a known relationship between the axial position, the rotational speed, and the varying parameter of the signal.

One or more techniques and/or systems are disclosed for identifying a position of an engine, such as the position of the pistons, camshaft, and/or crank shaft, during engine starting. In some implementations, a magnetic reluctance sensor can detect the reluctance from a proximate timing gear, resulting in an input voltage signal indicative of the detected reluctance. The input voltage signal can be converted to a digital voltage signal. A trigger threshold can set to identify a detection window. During the detection window, a zero-cross of the input voltage signal is detected to identify an engine position, and any other zero-crossing signals are not identified, thereby mitigating the effects of noise at the slow starting speeds.

One or more techniques and/or systems are disclosed for identifying a position of an engine, such as the position of the pistons, camshaft, and/or crank shaft, during engine starting. In some implementations, a magnetic reluctance sensor can detect the reluctance from a proximate timing gear, resulting in an input voltage signal indicative of the detected reluctance. The input voltage signal can be converted to a digital voltage signal. A trigger threshold can set to identify a detection window. During the detection window, a zero-cross of the input voltage signal is detected to identify an engine position, and any other zero-crossing signals are not identified, thereby mitigating the effects of noise at the slow starting speeds.

A compressor that includes a casing, a compression mechanism provided inside the casing to compress a refrigerant, a rotary shaft transmitting a rotational force to the compression mechanism from a drive source provided outside the casing, a clutch connecting the drive source and the rotary shaft by a magnetic force generated when electric power is applied to the clutch and disconnecting the drive source and the rotary shaft by losing the magnetic force when the electric power applied thereto is cut off, and a rotation measurement means for receiving the magnetic force from the clutch to measure a change in magnetic flux according to the rotation of the rotary shaft and measure a rotational speed of the rotary shaft. Thus, it is possible to measure the rotational speed of the rotary shaft without including a permanent magnet.

A compressor that includes a casing, a compression mechanism provided inside the casing to compress a refrigerant, a rotary shaft transmitting a rotational force to the compression mechanism from a drive source provided outside the casing, a clutch connecting the drive source and the rotary shaft by a magnetic force generated when electric power is applied to the clutch and disconnecting the drive source and the rotary shaft by losing the magnetic force when the electric power applied thereto is cut off, and a rotation measurement means for receiving the magnetic force from the clutch to measure a change in magnetic flux according to the rotation of the rotary shaft and measure a rotational speed of the rotary shaft. Thus, it is possible to measure the rotational speed of the rotary shaft without including a permanent magnet.

A rotation rate sensor, including at least: one oscillating mass, deflectable in a drive direction and in a detection direction oriented perpendicularly to the drive direction; one drive circuit for prompting a defined oscillatory movement of the oscillating mass in the drive direction; one circuit for detecting a measuring signal, which corresponds to the deflection of the oscillating mass in the detection direction; and one read-out circuit for reading out and pre-processing the measuring signal. The read-out circuit includes a demodulator, with which a useful signal and a quadrature signal are extractable from the measuring signal. The read-out circuit includes a sigma-delta A/D converter. An offset voltage is feedable to the sigma-delta A/D converter, which is selected in such a way that tonal artifacts in the frequency spectrum of the digitized useful signal are shifted into a frequency range outside of the bandwidths of the useful signal to be expected.

A rotation rate sensor, including at least: one oscillating mass, deflectable in a drive direction and in a detection direction oriented perpendicularly to the drive direction; one drive circuit for prompting a defined oscillatory movement of the oscillating mass in the drive direction; one circuit for detecting a measuring signal, which corresponds to the deflection of the oscillating mass in the detection direction; and one read-out circuit for reading out and pre-processing the measuring signal. The read-out circuit includes a demodulator, with which a useful signal and a quadrature signal are extractable from the measuring signal. The read-out circuit includes a sigma-delta A/D converter. An offset voltage is feedable to the sigma-delta A/D converter, which is selected in such a way that tonal artifacts in the frequency spectrum of the digitized useful signal are shifted into a frequency range outside of the bandwidths of the useful signal to be expected.

A rotation rate sensor, including at least: one oscillating mass, deflectable in a drive direction and in a detection direction oriented perpendicularly to the drive direction; one drive circuit for prompting a defined oscillatory movement of the oscillating mass in the drive direction; one circuit for detecting a measuring signal, which corresponds to the deflection of the oscillating mass in the detection direction; and one read-out circuit for reading out and pre-processing the measuring signal. The read-out circuit includes a demodulator, with which a useful signal and a quadrature signal are extractable from the measuring signal. The read-out circuit includes a sigma-delta A/D converter. An offset voltage is feedable to the sigma-delta A/D converter, which is selected in such a way that tonal artifacts in the frequency spectrum of the digitized useful signal are shifted into a frequency range outside of the bandwidths of the useful signal to be expected.

A rotation rate sensor, including at least: one oscillating mass, deflectable in a drive direction and in a detection direction oriented perpendicularly to the drive direction; one drive circuit for prompting a defined oscillatory movement of the oscillating mass in the drive direction; one circuit for detecting a measuring signal, which corresponds to the deflection of the oscillating mass in the detection direction; and one read-out circuit for reading out and pre-processing the measuring signal. The read-out circuit includes a demodulator, with which a useful signal and a quadrature signal are extractable from the measuring signal. The read-out circuit includes a sigma-delta A/D converter. An offset voltage is feedable to the sigma-delta A/D converter, which is selected in such a way that tonal artifacts in the frequency spectrum of the digitized useful signal are shifted into a frequency range outside of the bandwidths of the useful signal to be expected.