US 11,852,482 B2
Angular velocity sensor and angular velocity sensor system
Katsuaki Goto, Kariya (JP); Shota Harada, Kariya (JP); Takashi Katsumata, Kariya (JP); Yoshiyuki Hata, Kariya (JP); and Teruhisa Akashi, Kariya (JP)
Assigned to DENSO CORPORATION, Kariya (JP)
Filed by DENSO CORPORATION, Kariya (JP)
Filed on Apr. 27, 2022, as Appl. No. 17/730,752.
Application 17/730,752 is a continuation of application No. PCT/JP2020/040470, filed on Oct. 28, 2020.
Claims priority of application No. 2019-196694 (JP), filed on Oct. 29, 2019.
Prior Publication US 2022/0252398 A1, Aug. 11, 2022
Int. Cl. G01C 19/5726 (2012.01); G01C 19/5762 (2012.01); G01P 3/14 (2006.01)
CPC G01C 19/5726 (2013.01) [G01C 19/5762 (2013.01); G01P 3/14 (2013.01)] 13 Claims
OG exemplary drawing
 
1. An angular velocity sensor system configured to detect an angular velocity, the angular velocity sensor system comprising:
an angular velocity sensor; and
a controller configured to execute predetermined processing, wherein:
the angular velocity sensor includes
a movable part including
a drive spring,
a detection spring,
a mass part supported via the drive spring and the detection spring, configured to vibrate in a first direction by deformation of the drive spring, and configured to vibrate in a second direction orthogonal to the first direction by deformation of the detection spring due to a Coriolis force when an angular velocity is applied while vibrating in the first direction,
a movable part drive electrode,
a movable part detection electrode, and
a movable part detection excitation electrode, and
a fixed part including
a fixed part drive electrode facing the movable part drive electrode,
a fixed part detection electrode facing the movable part detection electrode, and
a fixed part detection excitation electrode facing the movable part detection excitation electrode,
the angular velocity sensor includes
a drive spring adjustment part configured to change a spring constant of the drive spring, and
a detection spring adjustment part configured to change a spring constant of the detection spring,
the controller is configured to
vibrate the movable part in the second direction by applying a predetermined voltage to the fixed part detection excitation electrode and simultaneously vibrate the movable part in the first direction by applying a predetermined voltage to the fixed part drive electrode,
acquire a first resonance frequency of the movable part, which is in a direction along the first direction, and a second resonance frequency of the movable part, which is in a direction along the second direction,
adjust the spring constant of the drive spring by controlling the drive spring adjustment part, such that the first resonance frequency is maintained at a constant value,
adjust the spring constant of the detection spring by controlling the detection spring adjustment part, such that the second resonance frequency is maintained at a constant value, and
detect the angular velocity on a basis of a result of synchronously detecting a signal from the fixed part detection electrode with the first resonance frequency,
the movable part has, as the second resonance frequency, a detection resonance frequency and a non-detection resonance frequency, which is different from the detection resonance frequency and the first resonance frequency, and
the controller is configured to
acquire, as the second resonance frequency, the non-detection resonance frequency, and
control the detection spring adjustment part to adjust the spring constant of the detection spring, such that the non-detection resonance frequency is maintained at a constant value.