Driving spring of full-decoupling three-axis micromechanical gyroscope

Abstract

The utility model discloses a driving spring of a full-decoupling three-axis micromechanical gyroscope, which is used for connecting a central elastic mechanism and a mass block of an adjacent detection mechanism around the central elastic mechanism, and the central elastic mechanism is provided with a central frame which is connected to an anchor point through an inner elastic beam and a transition beam. Two symmetrical driving springs are connected between each side edge of the central frame and the mass block of the adjacent detection mechanism, each driving spring is composed of a segmented S-shaped outer elastic beam, and the overall extending direction of a long-strip-shaped rod of the S-shaped outer elastic beam conforms to the driving vibration direction of the corresponding mass block. According to the utility model, the driving spring is twisted by 90 degrees in the length direction, so that the driving spring is vertical to the torsion shaft along the driving direction, and the linear displacement can be effectively improved. And even if the long-strip-shaped rod of the S-shaped outer elastic beam has a side wall inclination angle due to a process error, orthogonal coupling can be effectively prevented, so that the capacitance detection numerical value precision caused by the movement of the mass block is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to microcomputer gyroscope especially relates to a full decoupling three -axis micromechanical gyroscope's center elastic mechanism belongs to microcomputer system field. BACKGROUND

[0002] Gyroscope is used to detect the angular velocity of the device, in the industry has quite mature research and development maturity. For example, there is a patent application (application number: 202311849847.2) discloses a full decoupling three -axis micromechanical gyroscope. This application designs independent detection mechanism for each axis to reduce the cross talk between the output signal of each axis.

[0003] The detection principle of gyroscope is known, and in order to pursue higher performance chip level gyroscope product, the suppression of orthogonal coupling becomes a major direction of product research and development. Because such gyroscope chip is small, various elastic beams in the product are micro-machined and etched, and process error often makes the cross section of the beam parallelogram (or tends to parallelogram), and the probability of tilting in the same direction. When there is no actual acceleration in the detection direction, the driving motion of the two mass blocks will be driven to produce up and down fluctuations due to the side wall tilt of the beam. That is, the driving motion is coupled to the orthogonal coupling of the detection direction.

[0004] As shown in Figure 1 The above full decoupling three -axis micromechanical gyroscope, each mass block 1a, 1b and center elastic mechanism 2 are connected through each folding connecting part 3' (also called "drive spring"). The length direction of the drive spring is parallel to the torsion axis N of the corresponding mass block, which will easily lead to the above-mentioned orthogonal coupling, thereby causing detection error. SUMMARY

[0005] The utility model discloses a kind of drive springs of full decoupling three -axis micromechanical gyroscope, solve the problem that abnormal orthogonal coupling of gyroscope is caused by the elastic beam formed by process error.

[0006] To achieve the above object, the utility model provides the following technical scheme: a kind of drive spring of full decoupling three -axis micromechanical gyroscope, for connecting the mass block of center elastic mechanism and its periphery adjacent detection mechanism, the center elastic mechanism is equipped with center frame connected to anchor point by inner elastic beam and transition beam, each side of the center frame is connected with the mass block of adjacent detection mechanism between two symmetrical drive springs, each drive spring is composed of segmented S-shaped outer elastic beam, and the overall extension direction of the long strip-shaped rod of S-shaped outer elastic beam complies with the driving vibration direction of corresponding mass block.

[0007] Further, the driving spring is provided with a first S-shaped outer elastic beam close to a corner of the central frame and a second S-shaped outer elastic beam close to the middle of the mass block, and a block-shaped first connecting part is integrally connected between the two S-shaped outer elastic beams.

[0008] Further, the four anchor points are distributed in a square four-corner shape on the inner side of the central frame, and are divided into two groups by the vertical center line, and a S-shaped inner elastic beam is arranged between the upper and lower anchor points of each group, and a cross-shaped transition beam is connected between the two S-shaped inner elastic beams, and the other two free ends of the cross-shaped transition beam are connected with the central frame.

[0009] Further, the central frame is in a rectangular shape, and the central frame is outwardly provided with a vice-shaped auxiliary frame along the upper and lower sides of the vertical center line, and is inwardly provided with a second connecting part with a concave-shaped end, and the two free ends of the transition beam are connected to the concave area of the adjacent second connecting part.

[0010] Compared with the prior art, the beneficial effects of the present application are as follows: by twisting the driving spring by 90 degrees in the length direction, it is perpendicular to the torsion shaft in the driving direction, which can effectively improve the linear displacement. Even if the side wall inclination angle of the long strip-shaped rod of the S-shaped outer elastic beam exists due to process error, it can effectively prevent the generation of orthogonal coupling, thereby improving the accuracy of the capacitance detection value caused by the movement of the mass block. BRIEF DESCRIPTION OF DRAWINGS

[0011] Figure 1 is the related structure diagram of the local driving spring in the existing gyroscope chip.

[0012] Figure 2 is the structure diagram of the driving spring connection of the central elastic mechanism improved by the present application for the gyroscope chip.

[0013] Figure 3 is the detail connection structure diagram of the central elastic mechanism of the present application DETAILED DESCRIPTION

[0014] The specific embodiments of the present application will be further described in detail below in combination with the embodiment drawings, so that the technical scheme of the present application is easier to understand and master, and the protection scope of the present application is more clearly defined.

[0015] The designer of the present application proposes an improved driving spring to avoid the generation of orthogonal coupling in view of the many disadvantages of the existing driving spring, such as the existence of inclination angle due to process and the resulting orthogonal coupling.

[0016] As Figure 2As shown, the driving spring is used to connect the center elastic mechanism 2 and the mass block of the adjacent detection mechanism. In this embodiment, only a pair of mass blocks arranged in the horizontal direction is used for principle illustration, and the principles of the other two axes are similar. As shown in the figure, the mass blocks 1a and 1b are respectively connected to the anchor point 5 through the elastic beam and are driven by the respective driving frame to swing left and right. The center elastic mechanism 2 is provided with a center frame 21 connected to the anchor point 4 through the inner elastic beam and the transition beam, the center frame 21 is kept in a suspended state, and each side of the center frame 21 is connected to the mass block of the adjacent detection mechanism through two driving springs 3 which are symmetrical (with the horizontal center line as the reference). Thus, the traction force transmitted from the mass block to the center frame is uniform, preventing the center frame from being abnormally twisted relative to the substrate. Each driving spring is composed of a segmented S-shaped outer elastic beam, and the overall extension direction of the long rod of the S-shaped outer elastic beam conforms to the driving vibration direction of the corresponding mass block. That is, it can be understood that the driving spring is twisted by 90 degrees in the length direction, so that even if the cross section of the long rod is formed at an angle due to process errors, the orthogonal coupling generated thereby can be effectively avoided in the left and right swinging direction of the mass block.

[0017] From the further refined features, as shown in Figure 3 For example, the upper right corner driving spring 3a identified by the dashed box is provided with a first segment S-shaped outer elastic beam 31a close to a corner of the center frame 21 and a second segment S-shaped outer elastic beam 32a close to the middle of the mass block 1b, and the two segment S-shaped outer elastic beams are integrally connected with a block-shaped first connecting part 33a. In particular, as shown by the bending of the first segment S-shaped outer elastic beam, the long rod 311a extends in the direction of the horizontal swinging of the mass block, and is perpendicular to the torsion axis N of the corresponding detection mechanism, while the short rod 312a has the same extension direction as the traditional driving spring, but due to its extremely short length, the orthogonal coupling it may cause can be ignored.

[0018] From the optimization of the detailed structure of the center elastic mechanism 2, a square four-corner distribution is provided inside the center frame, and is divided into two groups by the vertical center line. As shown from the right side, a segment S-shaped inner elastic beam 6 is provided between the upper anchor point 4d and the lower anchor point 4c, and the same is provided between the upper anchor point 4a and the lower anchor point 4b in the corresponding group, and the two segment S-shaped inner elastic beams are connected by a cross-shaped transition beam 7. As the name implies, the two free ends of the cross-shaped transition beam are connected to the S-shaped inner elastic beam, and the two free ends in the vertical direction are connected to the center frame. More specifically, the center frame 21 is arranged in a rectangular shape, and the center frame is provided with a vice frame 211 in a convex shape outward on the upper and lower sides along the vertical center line, and is provided with a second connecting part 212 in a concave shape inward; the two free ends of the transition beam in the vertical direction are respectively connected to the concave areas of the adjacent second connecting parts.

[0019] From the above introduction and embodiment details of the driving spring of the utility model, it can be seen that it has substantial characteristics and progress: by twisting the driving spring 90 degrees in the length direction, it is perpendicular to the twisting shaft in compliance with the driving direction, which can effectively improve the linear displacement. Even if the side wall inclination exists in the long strip-shaped rod of the S-shaped elastic beam due to process error, it can effectively prevent the generation of orthogonal coupling, thereby improving the accuracy of the capacitance detection value brought by the mass motion.

[0020] In addition to the above embodiments, the utility model can also have other implementation manners, and any technical solution formed by equivalent replacement or equivalent transformation falls within the scope of the utility model claimed.

Claims

1. A drive spring of a fully decoupled tri-axial micromechanical gyroscope for connecting a mass of a central elastic mechanism and its peripherally adjacent detection mechanisms, the central elastic mechanism being provided with a central frame connected to an anchor point by inner elastic beams and transition beams, characterized in that: Two driving springs symmetrically connected between each side edge of the center frame and the mass block of the adjacent detection mechanism, each of the driving springs is composed of segmented S-shaped outer elastic beams, and the overall extension direction of the long strip-shaped rod of the S-shaped outer elastic beam is consistent with the driving vibration direction of the corresponding mass block.

2. The drive spring of a fully decoupled three-axis micromechanical gyroscope according to claim 1, characterized in that: The driving spring is provided with a first S-shaped outer elastic beam close to a corner of the center frame and a second S-shaped outer elastic beam close to the middle of the mass block, and a block-shaped first connecting part is integrally connected between the two S-shaped outer elastic beams.

3. The drive spring of a fully decoupled three-axis micromechanical gyroscope according to claim 1, characterized in that: Four anchor points are distributed in a square four-corner manner on the inner side of the center frame, and are divided into two groups by the vertical center line, a S-shaped inner elastic beam is arranged between the upper and lower anchor points of each group, two S-shaped inner elastic beams are connected by a cross-shaped transition beam, and the other two free ends of the cross-shaped transition beam are connected with the center frame.

4. The drive spring of a fully decoupled three-axis micromechanical gyroscope according to claim 1 or 3, characterized in that: The center frame is arranged in a rectangular shape, and a convex-shaped auxiliary frame is arranged on the outer side of the center frame along the upper and lower sides of the vertical center line, and a concave-shaped second connecting part is arranged on the inner side of the center frame, the two free ends of the transition beam are connected to the recessed area of the adjacent second connecting part.

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