Gyro sensor, electronic device, and vehicle
A gyro sensor includes a substrate, a fixed section fixed to the substrate, a driving section configured to perform driving along an X axis parallel to a principal plane of the substrate, a mass section coupled to the driving section and displaced along the X axis, a detecting section coupled to the mass section, capable of turning around a Z axis crossing the X axis, and capable of being displaced along the Z axis by a Coriolis force acting on a turning motion horizontal to the substrate, and an elastic section coupling the detecting section and the fixed section. The fixed section is disposed between the center of gravity of the detecting section and the mass section in a plan view.
1. A gyro sensor comprising:
three mutually orthogonal axes being defined as an X-axis, a Y-axis, and a Z-axis;
a substrate; and
an element unit that is supported on the upper surface of the substrate located on the plus side of the Z axis and detects an angular velocity based on a change in capacitance, wherein
the element unit comprises:
a mass section configured to be displaced in an X-axis direction along the X-axis parallel to the upper surface of the substrate;
a driving section that drives the mass section in the X-axis direction;
a first fixed section fixed to the upper surface of the substrate;
a second fixed section fixed to the upper surface of the substrate;
a first detecting section that is connected to the mass section and is configured to be displaced in a Z-axis direction along the Z-axis;
a second detecting section that is connected to the mass section and is configured to be displaced in the Z-axis direction;
a first elastic section connecting the first detecting section and the first fixed section;
a second elastic section connecting the second detecting section and the second fixed section;
a first fixed detecting section facing the first detecting section and spaced apart from the first detecting section; and
a second fixed detecting section facing the second detecting section and spaced apart from the second detecting section, wherein
the mass section is arranged between the first detecting section and the second detecting section in a plan view from the Z-axis direction.
2. The gyro sensor according to claim 1 , wherein the element unit comprises:
a third fixed section fixed to the upper surface of the substrate and disposed on the positive side of the X-axis direction;
a fourth fixed section fixed to the upper surface of the substrate and disposed on the negative side of the X-axis direction;
a third elastic section connecting the positive end of the mass section in the X-axis direction and the third fixed section; and
a fourth elastic section connecting an end of the mass section on the negative side in the X-axis direction and the fourth fixed section.
3. The gyro sensor according to claim 1 , wherein
the first detecting section and the second detecting section rotate in opposite phases along a plane including the X-axis and the Y-axis.
4. The gyro sensor according to claim 1 , wherein
the first elastic section includes a fold, and
the second elastic section includes a fold.
5. The gyro sensor according to claim 4 , wherein
the first elastic section includes folds on the plus side and the minus side in the X-axis direction, and
the second elastic section includes folds on the plus side and the minus side in the X-axis direction.
6. The gyro sensor according to claim 1 , wherein
the first detecting section is arranged on a plus side of the Y axis and is arranged, and
the second detecting section is arranged on a minus side of the Y axis.
7. The gyro sensor according to claim 1 , wherein the element part comprises:
a first joining section connecting the first detecting section and the first elastic section; and
a second joining section connecting the second detecting section and the second elastic section.
8. The gyro sensor according to claim 5 , wherein
a first groove is provided on the connection side of the first detecting section with the first joining section.
9. The gyro sensor according to claim 5 , wherein
a second groove is provided on the connection side of the second detecting section with the second joining section.
10. The gyro sensor according to claim 1 , further comprising:
a first coupling spring connecting the mass section and the first detecting section and extending along the Y-axis; and
a second coupling spring connecting the mass section and the second detecting section and extending along the Y-axis.
11. The gyro sensor according to claim 1 , wherein
the first fixed detecting section and the second fixed detecting section are arranged on an upper surface of the substrate.
12. The gyro sensor according to claim 1 , wherein
the first fixed section is disposed between a center of gravity of the first fixed detecting section and the mass section in a plan view, and
the second fixed section is disposed between a center of gravity of the second fixed detecting section and the mass section in a plan view.
13. An electronic device comprising the gyro sensor according to claim 1 .
14. A vehicle comprising the gyro sensor according to claim 1 .