Triaxial micro-electromechanical gyroscope

• US 10,330,471 B2
• Filed: 07/23/2015
• Issued: 06/25/2019
• Est. Priority Date: 11/27/2014
• Status: Active Grant

• Current Assignee: Weifang Goertek Microelectronics Co., Ltd. (Goertek Incorporated)
• Original Assignee: Goertek Incorporated
• Inventors: Zhang, Tingkai
• Primary Examiner(s): Evanisko, Leslie J
• Assistant Examiner(s): Parco, Jr., Ruben C
• Application Number:
  US15/529,491
• Publication Number:
  US 20170261321A1
• Time in Patent Office: 1,433 Days
• CPC Class Codes: B81B 7/0003 MEMS mechanisms for assembling automatically hinged components, self-assembly devices self-assembly processes B81C1/00007
• CPC Class Codes: B81B 7/008 MEMS characterised by an electronic circuit specially adapted for controlling or driving the same B81B7/0087 takes precedence; arrangements for starting, regulating, braking, or otherwise controlling an actuator H02N; control arrangements or circuits for visual indicators G09G3/00
• CPC Class Codes: G01C 19/08 electrically driven G01C19/14 takes precedence
• CPC Class Codes: G01C 19/26 Caging, i.e. immobilising moving parts, e.g. for transport
• CPC Class Codes: G01C 19/56 Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces
• CPC Class Codes: G01C 19/5684 the devices involving a micromechanical structure
• CPC Class Codes: G01C 19/5691 of essentially three-dimensional vibrators, e.g. wine glass-type vibrators
• CPC Class Codes: G01C 19/5733 Structural details or topology

Abstract

The present invention is related to a triaxial micro-electromechanical gyroscope, comprising: a ring-shaped detection capacitor located at the center; two sets of driving capacitors located at outer sides of the ring-shaped detection capacitor and symmetrically distributed at two sides of an origin along a y-axis; two sets of second detection capacitors located at the outer sides of the ring-shaped detection capacitor respectively and symmetrically distributed at the two sides of the origin along an x-axis; and a linkage part connected with movable polar plates of the driving capacitors, movable polar plates of the second detection capacitors, and an outer edge of ring-shaped upper polar plates of the ring-shaped detection capacitor, respectively. The triaxial micro-electromechanical gyroscope provided by the present invention adopts a single structure design, and integrates capacitive electrostatic driving and differential capacitive detection.

Claims

1. A triaxial micro-electromechanical gyroscope, comprising:

a substrate;

a ring-shaped detection capacitor located at a central position of the substrate, wherein the center of the ring-shaped detection capacitor is an origin, the ring-shaped detection capacitor includes four lower polar plates fixed onto the substrate and a ring-shaped upper polar plate that directly faces and is hung above the four lower polar plates, the four lower polar plates are divided into two groups, the first group of lower polar plates is symmetrically distributed at two sides of the origin along an x-axis, and cooperates with the corresponding ring-shaped upper polar plate to form a set of first detection capacitors, the second group of lower polar plates is symmetrically distributed at the two sides of the origin along a y-axis, and cooperates with the corresponding ring-shaped upper polar plate to form another set of first detection capacitors, and the ring-shaped upper polar plate is fixed onto the substrate at the origin via a first anchor point;

two sets of driving capacitors which are located at the outer sides of the ring-shaped detection capacitor respectively and are symmetrically distributed at the two sides of the origin along the y-axis, wherein each set of the driving capacitors comprises a movable driving electrode and a fixed driving electrode which cooperate with each other;

two sets of second detection capacitors which are located at the outer sides of the ring-shaped detection capacitor respectively and are symmetrically distributed at the two sides of the origin along the x-axis, wherein each set of the second detection capacitors comprises a movable detection electrode and a fixed detection electrode which cooperate with each other; and

a linkage part connected with the movable driving electrodes, the movable detection electrodes, and outer edges of the ring-shaped upper polar plate, respectively, wherein the driving capacitors are configured for providing driving forces in the y-axis direction, and driving the movable detection electrodes to linearly move in the y-axis direction as well as the ring-shaped upper polar plate to rotate around the first anchor point via the linkage part,

the linkage part comprises a rectangular outer frame and a first linkage part located inside the rectangular outer frame, wherein the rectangular outer frame encircles the ring-shaped detection capacitor, and the rectangular outer frame is connected with the outer edges of the ring-shaped upper polar plate via the first linkage part;

the two sets of driving capacitors are symmetrically distributed at two sides, parallel to the x-axis, of the rectangular outer frame, and the movable driving electrodes are connected with sides, parallel to the x-axis, of the rectangular outer frame;

the two sets of second detection capacitors are symmetrically distributed at two sides, parallel to the y-axis, of the rectangular outer frame, and the movable detection electrodes are connected with sides, parallel to the y-axis, of the rectangular outer frame; and

the driving capacitors drive the rectangular outer frame to linearly move in the y-axis direction, and the rectangular outer frame that linearly moves in the y-axis direction drives the ring-shaped upper polar plate to rotate around the first anchor point via the first linkage part, wherein;

the first linkage part includes a first linkage beam, two lever beams, two second linkage beams and a third linkage beam;

the first linkage beam and the second linkage beams are parallel to the y-axis, and the lever beams and the third linkage beam are parallel to the x-axis;

the two lever beams are respectively connected with the first linkage beam to form a box structure with an open end.

2. The triaxial micro-electromechanical gyroscope of claim 1, wherein:

the movable driving electrodes and the fixed driving electrodes are comb-shaped electrodes, and the movable detection electrodes and the fixed detection electrodes are comb-shaped electrodes.

3. The triaxial micro-electromechanical gyroscope of claim 1, wherein:

the ring-shaped upper polar plate takes the shape of a ring or a square ring.

4. The triaxial micro-electromechanical gyroscope of claim 1, wherein:

the two lower polar plates in the first group of lower polar plates have the same shape, and the two lower polar plates in the second group of lower polar plates have the same shape.

5. The triaxial micro-electromechanical gyroscope of claim 1, wherein:

the ring-shaped detection capacitor is located between the two lever beams;

the two second linkage beams are symmetrical with respect to the x-axis and are located between the lever beams and the rectangular outer frame;

one end of the second linkage beam is connected with the adjacent lever beam, and the other end thereof is connected with the rectangular outer frame; and

one end of the third linkage beam is connected with the middle part of the first linkage beam, and the other end thereof is connected with the outer edge of the ring-shaped upper polar plate.

6. The triaxial micro-electromechanical gyroscope of claim 5, wherein:

the first linkage part further comprises two support beams, and the two support beams are parallel to the y-axis, respectively;

the two support beams are symmetrical with respect to the x-axis and are located between the box structure and the ring-shaped detection capacitor;

one end of the support beam is connected with the adjacent lever beam, and the other end thereof is fixed onto the substrate via a third anchor point.

7. The triaxial micro-electromechanical gyroscope of claim 6, wherein:

the end, unconnected with the first linkage beam, of the lever beam serves as a support end, and the support ends of the two lever beams are fixed onto the substrate via second anchor points, respectively; and

a connection position of each second linkage beam and the corresponding lever beam is located in the middle of the support end of the lever beam and a connection point of the level beam and the corresponding support beam.

8. The triaxial micro-electromechanical gyroscope of claim 5, wherein:

the first linkage part further comprises a rectangular inner frame and a second linkage part, wherein the rectangular inner frame is located inside the rectangular outer frame and encircles the box structure, and the rectangular outer frame is connected with the rectangular inner frame via the second linkage part;

the second linkage beams are located between the lever beams and the rectangular inner frame, and are connected with the rectangular outer frame via the rectangular inner frame; and

the rectangular outer frame that linearly moves in the y-axis direction drives the rectangular inner frame to linearly move in the y-axis direction via the second linkage part.

9. The triaxial micro-electromechanical gyroscope of claim 8, wherein:

the second linkage part is composed of Z-type decoupling beams; and

one ends of the Z-type decoupling beams are connected to the sides, parallel to the y-axis, of the rectangular inner frame, and the other ends thereof are connected to the sides, parallel to the y-axis, of the rectangular outer frame.

10. The triaxial micro-electromechanical gyroscope of claim 1, wherein:

the linkage part comprises a three-layered rectangular frame, which is located on the substrate, adopts the origin as the center and includes an inner frame, an intermediate frame encircling the inner frame, and an outer frame encircling the intermediate frame from inside to outside sequentially, and each of the inner frame, the intermediate frame and the outer frame has two sides parallel to the x-axis while the other two sides thereof are parallel to the y-axis, wherein the outer frame is the rectangular outer frame;

the two sets of driving capacitors are symmetrically distributed at two sides, parallel to the x-axis, of the outer frame, and the movable driving electrodes are connected with the sides, parallel to the x-axis, of the outer frame;

the two sets of second detection capacitors are symmetrically distributed at two sides, parallel to the y-axis, of the outer frame, and the movable detection electrodes are connected with the sides, parallel to the y-axis, of the outer frame;

the outer frame is connected with the intermediate frame via first decoupling beams, and the first decoupling beams are arranged at the two sides, parallel to the y-axis, of the intermediate frame; and

the intermediate frame is connected with the inner frame via second decoupling beams, and the second decoupling beams are arranged at the two sides, parallel to the x-axis, of the inner frame;

the first linkage part is located inside the inner frame;

the two lever beams are symmetrical with respect to the x-axis, and the ring-shaped detection capacitor is located between the two lever beams;

the two second linkage beams are symmetrical with respect to the x-axis and are located between the lever beams and the rectangular outer frame;

one end of the second linkage beam is connected with the adjacent lever beam and the other end thereof is connected with the inner frame; and

one end of the third linkage beam is connected with the middle part of the first linkage beam, and the other end thereof is connected with the outer edge of the ring-shaped upper polar plate.

11. The triaxial micro-electromechanical gyroscope of claim 10, wherein:

the first decoupling beams comprise four Z-type decoupling beams symmetrical with respect to the y-axis, one ends of the Z-type decoupling beams are vertically connected with the sides, parallel to the y-axis, of the intermediate frame, and the other ends thereof are vertically connected with the sides, parallel to the y-axis, of the outer frame;

or the first decoupling beams comprise four L-type decoupling beams symmetrical with respect to the y-axis, one ends of the L-shaped decoupling beams are vertically connected with the sides, parallel to the y-axis, of the intermediate frame, and the other ends thereof are vertically connected with the sides, parallel to the x-axis, of the outer frame; and

the second decoupling beams comprise four Z-type decoupling beams symmetrical with respect to the x-axis, one ends of the Z-type decoupling beams are vertically connected with the sides, parallel to the x-axis, of the inner frame, and the other ends thereof are vertically connected with the sides, parallel to the x-axis, of the intermediate frame;

or the second decoupling beams comprise four L-type decoupling beams symmetrical with respect to the x-axis, one ends of the L-shaped decoupling beams are vertically connected with the sides, parallel to the x-axis, of the inner frame, and the other ends thereof are vertically connected with the sides, parallel to the y-axis, of the intermediate frame.

12. The triaxial micro-electromechanical gyroscope of claim 10, wherein:

the first linkage part further comprises two support beams, and the two support beams are parallel to the y-axis, respectively;

the two support beams are symmetrical with respect to the x-axis and are located between the box structure and the ring-shaped detection capacitor; and

one end of the support beam is connected with the adjacent lever beam, and the other end thereof is fixed onto the substrate via a third anchor point.

13. The triaxial micro-electromechanical gyroscope of claim 12, wherein:

the end, unconnected with the first linkage beam, of the lever beam serves as a support end, and the support ends of the two lever beams are fixed onto the substrate via second anchor points, respectively; and

a connection position of each second linkage beam and the corresponding lever beam is located between the support end of the lever beam and a connection point of the level beam and the corresponding support beam.

14. The triaxial micro-electromechanical gyroscope of claim 1, further comprising:

a support beam group located inside the ring holes of the ring-shaped detection capacitor, wherein the support beam group comprises an inner ring and an outer ring which are concentric, two inner ring support beams, two inner and outer ring connecting beams and four outer ring connecting beams;

one ends of the four outer ring connecting beams are respectively connected with the outer ring, and the other ends thereof are respectively connected with the inner edges of the ring-shaped upper polar plate;

the outer ring connecting beams are divided into two groups, one group of outer ring connecting beams is distributed along the x-axis, and the other group of outer ring connecting beams is distributed along the y-axis;

one ends of the two inner ring support beams are respectively connected with the inner ring, and the other ends thereof are fixed onto the substrate at the origin via the first anchor point;

one ends of the two inner and outer ring connecting beams are respectively connected with the inner ring, and the other ends thereof are respectively connected with the outer ring; and

the inner ring support beams are distributed along the y-axis, and the inner and outer ring connecting beams are distributed along the x-axis;

or, the inner ring support beams are distributed along the x-axis and the inner and outer ring connecting beams are distributed along the y-axis.

15. A triaxial micro-electromechanical gyroscope, comprising:

a substrate;

a ring-shaped detection capacitor located at a central position of the substrate, wherein the center of the ring-shaped detection capacitor is an origin, the ring-shaped detection capacitor includes four lower polar plates fixed onto the substrate and a ring-shaped upper polar plate that directly faces and is hung above the four lower polar plates, the four lower polar plates are divided into two groups, the first group of lower polar plates is symmetrically distributed at two sides of the origin along an x-axis, and cooperates with the corresponding ring-shaped upper polar plate to form a set of first detection capacitors, the second group of lower polar plates is symmetrically distributed at the two sides of the origin along a y-axis, and cooperates with the corresponding ring-shaped upper polar plate to form another set of first detection capacitors, and the ring-shaped upper polar plate is fixed onto the substrate at the origin via a first anchor point;

two sets of driving capacitors which are located at the outer sides of the ring-shaped detection capacitor respectively and are symmetrically distributed at the two sides of the origin along the y-axis, wherein each set of the driving capacitors comprises a movable driving electrode and a fixed driving electrode which cooperate with each other;

two sets of second detection capacitors which are located at the outer sides of the ring-shaped detection capacitor respectively and are symmetrically distributed at the two sides of the origin along the x-axis, wherein each set of the second detection capacitors comprises a movable detection electrode and a fixed detection electrode which cooperate with each other; and

a linkage part connected with the movable driving electrodes, the movable detection electrodes, and outer edges of the ring-shaped upper polar plate, respectively, wherein the driving capacitors are configured for providing driving forces in the y-axis direction, and driving the movable detection electrodes to linearly move in the y-axis direction as well as the ring-shaped upper polar plate to rotate around the first anchor point via the linkage part,

wherein;

the linkage part comprises a three-layered rectangular frame, which is located on the substrate, adopts the origin as the center and includes an inner frame, an intermediate frame encircling the inner frame, and an outer frame encircling the intermediate frame from inside to outside sequentially.