Sensor module

Abstract

To provide a sensor module capable of suppressing vibration leakage.SOLUTION: A sensor module comprises: a sensor substrate having a first inertial sensor that is driven at a first drive frequency, a second inertial sensor that is driven at a second drive frequency different from the first drive frequency, and a substrate on which the first and second inertial sensors are mounted; a case that covers the first and second inertial sensors; and a filling member that is filled between the case and the sensor substrate and covers at least a part of each of the first and second inertial sensors. The filling member has: a first filling member including the first drive frequency within a range of a full width at half maximum of a loss coefficient; and a second filling member including the second drive frequency within the range of the full width at half maximum of the loss coefficient.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a sensor module. [Background technology]

[0002] The inertial measurement unit described in Patent Document 1 has an inner case, a sensor board mounted on the underside of the inner case, and an outer case that covers the inner case and houses the sensor board between the inner case and the outer case. The sensor board also has a substrate, a Z-axis angular velocity sensor and an acceleration sensor mounted on the top surface of the substrate, and an X-axis angular velocity sensor and a Y-axis angular velocity sensor mounted on the side surface of the substrate.

[0003] A recess is formed on the bottom surface of the inner case, and the X-axis, Y-axis, and Z-axis angular velocity sensors and acceleration sensors are arranged in positions that overlap this recess. The recess is filled with a filling material, which seals the entire Z-axis angular velocity sensor and acceleration sensor, and the upper halves of the X-axis and Y-axis angular velocity sensors.

[0004] In the inertial measurement device of Patent Document 1, the placement of a filler member reduces the influence of external noise vibrations and improves the stability of detection accuracy. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2017-020829 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the inertial measurement device of Patent Document 1 has a problem in that vibrations from the X-axis angular velocity sensor, the Y-axis angular velocity sensor, and the Z-axis angular velocity sensor tend to leak outside the device via the filling member. [Means for solving the problem]

[0007] The sensor module of the present invention includes a sensor substrate having a first inertial sensor that is driven at a first drive frequency, a second inertial sensor that is driven at a second drive frequency different from the first drive frequency, and a substrate on which the first inertial sensor and the second inertial sensor are mounted; a case that covers the first inertial sensor and the second inertial sensor; a filling member filled between the case and the sensor substrate and covering at least a portion of each of the first inertial sensor and the second inertial sensor; The filling member includes a first filling member that includes the first driving frequency within a full width at half maximum range of the loss factor, and a second filling member that includes the second driving frequency within a full width at half maximum range of the loss factor. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is an exploded perspective view showing a sensor module according to a first embodiment. [Figure 2] FIG. 10 is a cross-sectional view of the sensor module as seen from the negative side in the Y-axis direction. [Figure 3] FIG. 10 is a cross-sectional view of the sensor module as seen from the negative side in the X-axis direction. [Figure 4] FIG. 2 is a plan view showing an angular velocity sensor. [Figure 5] FIG. 2 is a cross-sectional view showing an angular velocity sensor. [Figure 6] FIG. 2 is a schematic diagram showing a driving state of an angular velocity sensor. [Figure 7] FIG. 2 is a schematic diagram showing a driving state of an angular velocity sensor. [Figure 8] 1 is a graph showing the relationship between loss factor η and frequency. [Figure 9] 1 is a graph showing the relationship between loss factor η and frequency. [Figure 10] FIG. 10 is a diagram showing a state in which a plurality of sensor modules are mounted on one substrate. [Figure 11] 10 is a flowchart showing a manufacturing process of the sensor module. [Figure 12] 10A to 10C are cross-sectional views illustrating a method for manufacturing a sensor module. [Figure 13] 10A to 10C are cross-sectional views illustrating a method for manufacturing a sensor module. [Figure 14] 10A to 10C are cross-sectional views illustrating a method for manufacturing the sensor module. [Figure 15] 10A to 10C are cross-sectional views illustrating a method for manufacturing the sensor module. [Figure 16] 10A to 10C are cross-sectional views illustrating a method for manufacturing a sensor module. [Figure 17] FIG. 2 is a cross-sectional view showing a modified example of the sensor module shown in FIG. [Figure 18] FIG. 2 is a cross-sectional view showing a modified example of the sensor module shown in FIG. [Figure 19] FIG. 2 is a cross-sectional view showing a modified example of the sensor module shown in FIG. [Figure 20] FIG. 10 is an exploded perspective view showing a sensor module according to a second embodiment. [Figure 21] FIG. 10 is a cross-sectional view of the sensor module as seen from the negative side in the Y-axis direction. [Figure 22] FIG. 10 is a cross-sectional view of the sensor module as seen from the negative side in the X-axis direction. [Figure 23] 10 is a flowchart showing a manufacturing process of the sensor module. [Figure 24] 10A to 10C are cross-sectional views illustrating a method for manufacturing the sensor module. [Figure 25] 10A to 10C are cross-sectional views illustrating a method for manufacturing a sensor module. [Figure 26] 10A to 10C are cross-sectional views illustrating a method for manufacturing a sensor module. [Figure 27] FIG. 11 is a cross-sectional view showing the inside of a sensor module according to a third embodiment, as viewed from the positive side in the Z axis direction. [Figure 28] FIG. 10 is an exploded perspective view showing a sensor module according to a fourth embodiment. [Figure 29] FIG. 10 is a cross-sectional view of the sensor module as seen from the negative side in the Y-axis direction. DETAILED DESCRIPTION OF THE INVENTION

[0009] The sensor module of the present invention will be described in detail below based on the embodiments shown in the accompanying drawings. For ease of explanation, each figure except for Figures 11 and 23 illustrates three mutually orthogonal axes as the X-axis, Y-axis, and Z-axis. For ease of explanation, the direction parallel to the X-axis will also be referred to as the "X-axis direction," the direction parallel to the Y-axis will also be referred to as the "Y-axis direction," and the direction parallel to the Z-axis will also be referred to as the "Z-axis direction." The arrow side of the Z-axis direction will also be referred to as the "upper" and the opposite side as the "lower."

[0010] First Embodiment FIG. 1 is an exploded perspective view showing a sensor module according to a first embodiment. FIG. 2 is a cross-sectional view of the sensor module seen from the negative side in the Y-axis direction. FIG. 3 is a cross-sectional view of the sensor module seen from the negative side in the X-axis direction. FIG. 4 is a plan view of an angular velocity sensor. FIG. 5 is a cross-sectional view of the angular velocity sensor. FIGS. 6 and 7 are schematic diagrams showing the driving state of the angular velocity sensor. FIGS. 8 and 9 are graphs showing the relationship between the loss coefficient η and frequency. FIG. 10 is a diagram showing a state in which multiple sensor modules are mounted on one substrate. FIG. 11 is a flowchart showing the manufacturing process of the sensor module. FIGS. 12 to 16 are cross-sectional views illustrating a method for manufacturing the sensor module. FIGS. 17 to 19 are cross-sectional views showing modified examples of the sensor module shown in FIG. 1.

[0011] The sensor module 1 shown in Fig. 1 is an inertial measurement unit (IMU) that detects the posture and behavior of an object to which the sensor is attached, such as an automobile or a robot. Note that the object to which the sensor is attached is not limited to a moving body such as an automobile or a robot, but may also be a structure such as a bridge, an elevated road, or a track. When the sensor module 1 is attached to a structure, the sensor module 1 is used as a structural health monitoring system that checks the soundness of the structure.

[0012] 1, the sensor module 1 includes a case 2, a sensor substrate 50 housed in the case 2, and a filler 9 filled between the case 2 and the sensor substrate 50. The sensor substrate 50 also includes a substrate 5, an X-axis angular velocity sensor 7X as a first inertial sensor, a Y-axis angular velocity sensor 7Y as a second inertial sensor, a Z-axis angular velocity sensor 7Z as a third inertial sensor, a circuit element 51, and a connector 52, all of which are mounted on the substrate 5.

[0013] In this embodiment, for convenience of explanation, the X-axis angular velocity sensor 7X is the first inertial sensor, the Y-axis angular velocity sensor 7Y is the second inertial sensor, and the Z-axis angular velocity sensor 7Z is the third inertial sensor, but this is not limited to this, and it is arbitrary which of the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z are the first, second, and third angular velocity sensors. Also, in this embodiment, angular velocity sensors are used as the first, second, and third inertial sensors, but this is not particularly limited, and inertia other than angular velocity, for example, acceleration sensors that measure acceleration, may be used.

[0014] Each part of the sensor module 1 will be described below in order.

[0015] <Case 2> As shown in FIG. 1 , the case 2 has an inner case 3, an outer case 4 that covers the inner case 3, and a seal ring R that is interposed between the inner case 3 and the outer case 4. The inner case 3 and the outer case 4 are each made of aluminum (Al). This provides the case 2 with sufficiently high rigidity. In particular, in this embodiment, the surfaces of the inner case 3 and the outer case 4 are each anodized to provide insulation to the case 2. However, the constituent materials of the inner case 3 and the outer case 4 are not particularly limited, and may be metal materials such as titanium, magnesium, and stainless steel, or ceramics such as alumina and titania.

[0016] The inner case 3 has a rectangular parallelepiped shape with two diagonally opposite corners chamfered flat. Screw holes 31 for fixing the outer case 4 are formed in the other two diagonally opposite corners of the inner case 3. The inner case 3 also has a bottomed recess 32 that opens to the top surface, and a through-hole 33 that penetrates the top and bottom surfaces. The recess 32 and the through-hole 33 are aligned in the X-axis direction. Screw holes 34 for fixing the sensor substrate 50 are formed on both sides of the through-hole 33 in the Y-axis direction.

[0017] As shown in Fig. 1, the outer case 4 is a rectangular box-shaped body that opens downward. The outer case 4 covers the inner case 3 from above by inserting the inner case 3 into a recess 43 that opens on the bottom surface. The shape of the opening of the outer case 4 is aligned with the outer shape of the inner case 3. This prevents the outer case 4 from rattling relative to the inner case 3.

[0018] Furthermore, screw insertion holes 41 that overlap with the screw holes 31 are formed in two corners located on one diagonal of the outer case 4. Then, the inner case 3 and the outer case 4 are fixed together by inserting a screw B1 into the screw insertion hole 41 and fastening it into the screw hole 31. However, the method for fixing the inner case 3 and the outer case 4 is not particularly limited. Screw insertion holes 42 are formed in two corners located on the other diagonal of the outer case 4. Then, the sensor module 1 is attached to a support body (not shown) by inserting a screw B2 into the screw insertion hole 42 and fastening it into the support body. However, the method for attaching the sensor module to the support body is not particularly limited.

[0019] <Board 5> The substrate 5 is a circuit board and is made of, for example, a multi-layer glass epoxy substrate. However, the configuration of the substrate 5 is not particularly limited, and it may be, for example, a multi-layer ceramic substrate.

[0020] As shown in FIG. 1 , the substrate 5 has an upper surface 5a and a lower surface 5b, which are opposite surfaces. The substrate 5 also has side surfaces connecting the upper surface 5a and the lower surface 5b. These side surfaces include a first side surface 5c facing the negative side in the X-axis direction and a second side surface 5d facing the positive side in the Y-axis direction. The substrate 5 having such a configuration is placed on a mounting surface F, which is the upper surface of the inner case 3, with the upper surface 5a facing upward. The substrate 5 also has a pair of screw insertion holes 54 formed in the substrate 5 when placed on the mounting surface F, which overlap with the pair of screw holes 34. The substrate 5 and the inner case 3 are fixed together by inserting screws B3 into the screw insertion holes 54 and tightening them into the screw holes 34. However, the method for fixing the substrate 5 and the inner case 3 is not particularly limited.

[0021] On such a substrate 5, an X-axis angular velocity sensor 7X, a Y-axis angular velocity sensor 7Y, a Z-axis angular velocity sensor 7Z, a circuit element 51, and a connector 52 are mounted.

[0022] Connector 52 1, the connector 52 is mounted on the lower surface 5b of the substrate 5. The connector 52 is a plug-type connector, and is exposed to the outside of the sensor module 1 through a through-hole 33 formed in the inner case 3. This facilitates electrical connection between the sensor module 1 and an external device.

[0023] <X-axis, Y-axis, Z-axis angular velocity sensors 7X, 7Y, 7Z> As shown in Fig. 1, the X-axis angular velocity sensor 7X is mounted on the first side surface 5c of the substrate 5, facing the negative side in the X-axis direction. As shown in Fig. 2, the X-axis angular velocity sensor 7X is longer in the Z-axis direction than the substrate 5, and protrudes from both the top and bottom of the substrate 5. The bottom end of the X-axis angular velocity sensor 7X (the portion below the substrate 5) is housed in the recess 32. The X-axis angular velocity sensor 7X detects an angular velocity ωx about the X-axis.

[0024] As shown in Fig. 1, the Y-axis angular velocity sensor 7Y is mounted on the second side surface 5d of the substrate 5, facing the positive side in the Y-axis direction. As shown in Fig. 3, the Y-axis angular velocity sensor 7Y is longer in the Z-axis direction than the substrate 5, and protrudes from both the top and bottom of the substrate 5. The bottom end of the Y-axis angular velocity sensor 7Y (the portion below the substrate 5) is housed in the recess 32. The Y-axis angular velocity sensor 7Y detects an angular velocity ωy around the Y-axis.

[0025] As shown in Fig. 1, Z-axis angular velocity sensor 7Z is mounted on lower surface 5b of substrate 5 facing downward, i.e., toward the negative side in the Z-axis direction. As shown in Figs. 2 and 3, Z-axis angular velocity sensor 7Z is entirely housed in recess 32. Such Z-axis angular velocity sensor 7Z detects angular velocity ωz around the Z-axis.

[0026] The X-axis angular velocity sensor 7X, Y-axis angular velocity sensor 7Y, and Z-axis angular velocity sensor 7Z are each packaged surface-mounted components. This allows them to exhibit higher mechanical strength than components with exposed elements. Furthermore, this makes it easier to mount the X-axis angular velocity sensor 7X, Y-axis angular velocity sensor 7Y, and Z-axis angular velocity sensor 7Z on the substrate 5.

[0027] In addition, the X-axis angular velocity sensor 7X, the Y-axis angular velocity sensor 7Y, and the Z-axis angular velocity sensor 7Z have the same basic configuration except that the vibration frequencies of the sensor elements 74, which will be described later, are different in order to suppress interference between them, and they are arranged at right angles to each other so that their detection axes face the X-axis, Y-axis, and Z-axis.

[0028] 4 and 5, each of the X-axis angular velocity sensor 7X, the Y-axis angular velocity sensor 7Y, and the Z-axis angular velocity sensor 7Z includes a package 71 and a sensor element 74 housed in the package 71. The package 71 also includes a box-shaped base 72 having a recess 721 and supporting the sensor element 74 housed in the recess 721, and a lid 73 joined to the base 72 so as to close the opening of the recess 721. A connection terminal (not shown) electrically connected to the sensor element 74 is formed on the base 72, and the base 72 is electrically connected to the substrate 5 via the connection terminal.

[0029] The sensor element 74 is, for example, a quartz crystal vibration element having a drive vibration arm and a detection vibration arm. In the illustrated configuration, the quartz crystal vibration element has a base 740 fixed to a base 72 via a support substrate 75, four drive vibration arms 742, and two detection vibration arms 741. In such a quartz crystal vibration element, when an angular velocity ω about the detection axis J is applied while a drive signal is applied to drive and vibrate the drive vibration arm 742 as shown in FIG. 6, a detection vibration is excited in the detection vibration arm 741 by the Coriolis force as shown in FIG. 7. Then, charge generated in the detection vibration arm 741 by the detection vibration is extracted as a detection signal, and the angular velocity ω can be calculated based on the extracted detection signal.

[0030] The configurations of X-axis angular velocity sensor 7X, Y-axis angular velocity sensor 7Y, and Z-axis angular velocity sensor 7Z have been explained above. X-axis angular velocity sensor 7X is arranged so that its detection axis J is along the X-axis, Y-axis angular velocity sensor 7Y is arranged so that its detection axis J is along the Y-axis, and Z-axis angular velocity sensor 7Z is arranged so that its detection axis J is along the Z-axis. This allows X-axis angular velocity sensor 7X to detect angular velocity ωx, Y-axis angular velocity sensor 7Y to detect angular velocity ωy, and Z-axis angular velocity sensor 7Z to detect angular velocity ωz.

[0031] As described above, in order to suppress mutual interference, the X-axis angular velocity sensor 7X, the Y-axis angular velocity sensor 7Y, and the Z-axis angular velocity sensor 7Z have different drive frequencies (frequencies of the drive signals) for vibrating the drive vibration arms 742 of the sensor elements 74. For example, the first drive frequency f1, which is the drive frequency of the sensor element 74 of the X-axis angular velocity sensor 7X, can be set in the range of 48.5 to 50.0 kHz, the second drive frequency f2, which is the drive frequency of the sensor element 74 of the Y-axis angular velocity sensor 7Y, can be set in the range of 50.5 to 52.0 kHz, and the third drive frequency f3, which is the drive frequency of the sensor element 74 of the Z-axis angular velocity sensor 7Z, can be set in the range of 52.5 to 54.0 kHz.

[0032] However, the configurations of the X-axis angular velocity sensor 7X, the Y-axis angular velocity sensor 7Y, and the Z-axis angular velocity sensor 7Z are not particularly limited. For example, they may be configured using silicon MEMS vibration elements as the sensor elements.

[0033] <Circuit element 51> 1, the circuit element 51 is mounted on the upper surface 5a of the substrate 5. The circuit element 51 is electrically connected to the X-axis angular velocity sensor 7X, the Y-axis angular velocity sensor 7Y, and the Z-axis angular velocity sensor 7Z via the substrate 5. Such a circuit element 51 is, for example, an MCU (Micro Controller Unit), and controls each part of the sensor module 1. Specifically, the circuit element 51 has a control circuit that controls the driving of the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z, and an interface circuit that communicates with the outside.

[0034] The control circuit controls the driving of the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z, and detects angular velocities ωx, ωy, and ωz around the X-axis, Y-axis, and Z-axis based on the detection signals output from the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z. The interface circuit transmits and receives signals, receives commands from an external device, and outputs the detected angular velocities ωx, ωy, and ωz to the external device. While the communication method of the interface circuit is not particularly limited, in this embodiment, SPI (Serial Peripheral Interface) communication is used. SPI communication is a communication method suitable for connecting multiple sensors. Since all signals related to the angular velocities ωx, ωy, and ωz can be output from a single pin, the sensor module 1 can have fewer pins.

[0035] In addition to the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z, circuit element 51, and connector 52, multiple electronic components are mounted on the substrate 5, but for the sake of convenience, they will not be shown or described.

[0036] <Filling material 9> As shown in FIGS. 2 and 3 , the filler 9 fills the recess 32, i.e., the space between the sensor substrate 50 and the inner case 3. The filler 9 is also filled so as to fill the recess 32. Therefore, approximately the lower half of the X-axis angular velocity sensor 7X, which is vertically disposed on the first side surface 5c of the substrate 5, is covered and sealed with the filler 9. Similarly, approximately the lower half of the Y-axis angular velocity sensor 7Y, which is vertically disposed on the second side surface 5d of the substrate 5, is covered and sealed with the filler 9. In contrast, the Z-axis angular velocity sensor 7Z, which is horizontally disposed on the lower surface 5b of the substrate 5, is entirely covered and sealed with the filler 9. The filler 9 attenuates vibrations of the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z, thereby suppressing interference between the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z and vibration leakage from the sensor module 1.

[0037] The filling member 9 includes a first filling member 91, a second filling member 92, and a third filling member 93, each having a different rigidity. The first filling member 91 corresponds to the first inertial sensor, i.e., the X-axis angular velocity sensor 7X in this embodiment, and effectively damps vibrations of the X-axis angular velocity sensor 7X. The second filling member 92 corresponds to the second inertial sensor, i.e., the Y-axis angular velocity sensor 7Y in this embodiment, and effectively damps vibrations of the Y-axis angular velocity sensor 7Y. The third filling member 93 corresponds to the third inertial sensor, i.e., the Z-axis angular velocity sensor 7Z in this embodiment, and effectively damps vibrations of the Z-axis angular velocity sensor 7Z. While the first, second, and third inertial sensors are included in this embodiment, at least one of the inertial sensors may be omitted. In this case, any one of the first filling member 91, the second filling member 92, and the third filling member 93 may be omitted.

[0038] The first filling member 91, the second filling member 92, and the third filling member 93 are each formed in layers, and are stacked in the order of the third filling member 93, the second filling member 92, and the first filling member 91 from the bottom side of the recess 32. By stacking the first filling member 91, the second filling member 92, and the third filling member 93 in this manner in the depth direction of the recess 32, i.e., in the Z-axis direction, these can be formed in this order, as will be explained in the manufacturing method of the sensor module 1 described later, which makes it easier to manufacture the sensor module 1.

[0039] Among the first, second, and third filling members 91, 92, and 93, the third filling member 93 and the second filling member 92, which are located on the lower side and in the center, are not in contact with the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z. Specifically, the top surface of the second filling member 92 is located below the lower ends of the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z, and the third filling member 93 and the second filling member 92 are not in contact with any of the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z. Only the first filling member 91, which is located above the second filling member 92, is in contact with all of the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z. According to this configuration, as in the manufacturing method of the sensor module 1 described later, the second filling member 92 is formed on the hardened third filling member 93, and the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z are embedded in the unhardened first filling member 91 applied on the hardened second filling member 92, thereby forming the filling member 9 while suppressing mixing of the first, second, and third filling members 91, 92, and 93.

[0040] Here, in a configuration called a "constrained type" in which the filling member 9 is sandwiched between the sensor substrate 50 and the inner case 3, as in the sensor module 1, it is known that the loss coefficient η of the first, second, and third filling members 91, 92, and 93 each form a convex curve with respect to the vibration frequency, as shown in FIG. 8.

[0041] 8, the first filling member 91 is adjusted so that the first drive frequency f1 is located within a range of a full width at half maximum W11. The full width at half maximum W11 is the frequency width at which the loss factor η is half the peak p. With this configuration, the peak p of the loss factor η can be brought sufficiently close to the first drive frequency f1, so the first filling member 91 can effectively damp the vibration of the X-axis angular velocity sensor 7X caused by the drive vibration of the sensor element 74. As a result, the vibration of the X-axis angular velocity sensor 7X is less likely to be transmitted to the other Y-axis and Z-axis angular velocity sensors 7Y and 7Z, and is less likely to leak out of the sensor module 1.

[0042] More preferably, the first filling member 91 is adjusted so that the first driving frequency f1 is located within a range of a half width at half maximum W12. The half width at half maximum W12 is half the full width at half maximum W11, that is, the frequency width in which the loss factor η is ¾ of the peak p. In particular, in the first filling member 91 of this embodiment, the peak p of the loss factor η coincides with the first driving frequency f1. Thus, the closer the peak p of the loss factor η of the first filling member 91 is to the first driving frequency f1, the more remarkable the above-mentioned effect becomes. Note that the term "coincidence" mentioned above not only means that the peak p of the loss factor η coincides with the first driving frequency f1, but also includes, for example, a case in which there is a slight deviation (for example, about ±10%). The same applies hereinafter.

[0043] The second filling member 92 is also adjusted so that the second drive frequency f2 is located within the range of the full width at half maximum W21. With this configuration, the peak p of the loss factor η can be brought sufficiently close to the second drive frequency f2, so the second filling member 92 can effectively dampen the vibration of the Y-axis angular velocity sensor 7Y caused by the drive vibration of the sensor element 74. This makes it difficult for the vibration of the Y-axis angular velocity sensor 7Y to be transmitted to the other X-axis and Z-axis angular velocity sensors 7X and 7Z, and also makes it difficult for the vibration to leak out of the sensor module 1.

[0044] More preferably, the second filling member 92 is adjusted so that the second driving frequency f2 is located within the range of the half width at half maximum W22. In particular, in the second filling member 92 of this embodiment, the peak p of the loss factor η coincides with the second driving frequency f2. In this way, the closer the peak p of the loss factor η of the second filling member 92 is to the second driving frequency f2, the more pronounced the above-mentioned effect becomes.

[0045] The third filling member 93 is also adjusted so that the third drive frequency f3 is located within the range of the full width at half maximum W31. With this configuration, the peak p of the loss factor η can be brought sufficiently close to the third drive frequency f3, so the third filling member 93 can effectively damp the vibration of the Z-axis angular velocity sensor 7Z caused by the drive vibration of the sensor element 74. This makes it difficult for the vibration of the Z-axis angular velocity sensor 7Z to be transmitted to the other X-axis and Y-axis angular velocity sensors 7X and 7Y, and also makes it difficult for the vibration to leak out of the sensor module 1.

[0046] More preferably, the third filling member 93 is adjusted so that the third driving frequency f3 is located within the range of the half width at half maximum W32. In particular, in the third filling member 93 of this embodiment, the peak p of the loss factor η coincides with the third driving frequency f3. Thus, the closer the peak p of the loss factor η of the third filling member 93 is to the third driving frequency f3, the more pronounced the above-mentioned effect becomes.

[0047] Although not particularly limited, the peak value of the loss coefficient η of the first, second, and third filling members 91, 92, and 93 is preferably, for example, 0.05 or more and 0.1 or less, which enables the first, second, and third filling members 91, 92, and 93 to effectively damp vibrations of the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z.

[0048] The method for measuring the loss factor η is not particularly limited, and may be, for example, a resonance method such as a half-width method, an attenuation factor method, or a mechanical impedance method, or a non-resonance method other than these resonance methods.

[0049] The filler 9, which includes the first, second, and third filler members 91, 92, and 93 described above, has an overall loss coefficient η as shown in FIG. 9 . In this sensor module 1, the filler 9 can effectively damp vibrations of the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z. This effectively suppresses interference between the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z. In particular, in this embodiment, the first, second, and third drive frequencies f1, f2, and f3 are made different from one another, and the filler 9 is arranged in a two-stage configuration to suppress interference between the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z, resulting in a more pronounced interference suppression effect.

[0050] Furthermore, the sensor module 1 can effectively suppress vibration leakage to the outside. Therefore, for example, when multiple sensor modules 1 are mounted on a single substrate 100 as shown in FIG. 10 for the purpose of improving angular velocity detection accuracy, interference between the sensor modules 1 via the substrate 100 can be effectively suppressed. That is, it is possible to effectively suppress the following: leakage vibration from the X-axis angular velocity sensor 7X of one sensor module 1 propagating through the substrate 100 to the X-axis angular velocity sensor 7X of another sensor module 1 and causing noise; leakage vibration from the Y-axis angular velocity sensor 7Y of one sensor module 1 propagating through the substrate 100 to the Y-axis angular velocity sensor 7Y of another sensor module 1 and causing noise; and leakage vibration from the Z-axis angular velocity sensor 7Z of one sensor module 1 propagating through the substrate 100 to the Z-axis angular velocity sensor 7Z of another sensor module 1 and causing noise. This further improves angular velocity detection accuracy.

[0051] The first, second, and third filler members 91, 92, and 93 described above are not particularly limited. However, it is preferable to use a resin adhesive that has few intramolecular side chains and few intermolecular crosslinks, a linear main chain structure, and is prone to intermolecular friction during deformation. Examples of such resin adhesives include acrylic resin adhesives and vinyl acetate resin adhesives. Using such resin adhesives can efficiently convert the vibration energy of the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z into thermal energy. Therefore, vibrations of the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z can be more efficiently damped. The first, second, and third filler members 91, 92, and 93 can be formed with a loss factor η that satisfies the above requirements by selecting the resin base and curing agent, adjusting the blending conditions, and so on.

[0052] In contrast, epoxy resins, for example, have more intermolecular cross-linking points than the acrylic resin adhesives and vinyl acetate resin adhesives described above. This restricts intermolecular movement and reduces intermolecular friction. This makes it difficult to convert the vibration energy of the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z into thermal energy. On the other hand, silicone resins, for example, have freely rotatable bonds in their main chains. Even if intermolecular movement occurs, the main chains tend to rotate within each molecule, reducing intermolecular friction. This makes it difficult to convert the vibration energy of the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z into thermal energy. Thus, the materials for the first, second, and third filler members 91, 92, and 93 of the sensor module 1 were carefully considered.

[0053] The sensor module 1 has been described above. Next, a manufacturing method of the sensor module 1 will be described. As shown in FIG. 11 , the manufacturing method of the sensor module 1 includes a first filling step S11 of filling the recess 32 of the inner case 3 with an uncured third filling member 93, a first curing step S12 of curing the third filling member 93, a second filling step S13 of filling the recess 32 with an uncured second filling member 92 on the third filling member 93, a second curing step S14 of curing the second filling member 92, a third filling step S15 of filling the recess 32 with an uncured first filling member 91 on the second filling member 92, a sensor substrate mounting step S16 of mounting the sensor substrate 50 on the mounting surface F of the inner case 3, a third curing step S17 of curing the first filling member 91, and a case mounting step S18 of mounting the outer case 4 to the inner case 3. Note that, because the manufacturing method will be described below using the cross section shown in FIG. 2, some components will be described but not shown.

[0054] ≪First filling process S11≫ 12, in the first filling step S11, an uncured third filling member 93 is filled into the recess 32 of the inner case 3. By filling the recess 32 with the third filling member 93 in this manner, it is possible to suppress the wet spreading of the third filling member 93, and it is possible to form the third filling member 93 with high precision as designed.

[0055] ≪First curing step S12≫ In the first curing step S12, the third filling member 93 filled in the recess 32 is heated and cured.

[0056] ≪Second filling process S13≫ 13, in the second filling step S13, uncured second filling member 92 is filled onto the third filling member 93 in the recess 32 of the inner case 3. By filling the recess 32 with the second filling member 92 in this manner, it is possible to prevent the second filling member 92 from spreading due to wetting, and it is possible to form the second filling member 92 accurately and according to design. Note that, because the third filling member 93 is cured prior to this step, mixing of the third filling member 93 and the second filling member 92 is prevented.

[0057] ≪Second curing step S14≫ In the second curing step S14, the second filling member 92 filled in the recess 32 is heated and cured.

[0058] ≪Third filling process S15≫ 14, in the third filling step S15, an uncured first filling member 91 is filled onto the second filling member 92 in the recess 32 of the inner case 3. By filling the recess 32 with the first filling member 91 in this manner, it is possible to prevent the first filling member 91 from spreading due to wetting, and it is possible to form the first filling member 91 accurately and as designed. Note that, because the second filling member 92 is cured prior to this step, mixing of the second filling member 92 and the first filling member 91 is prevented.

[0059] <Sensor substrate placement step S16> 15, in the sensor substrate mounting process S16, the sensor substrate 50 is mounted on the mounting surface F of the inner case 3. Then, the inner case 3 and the sensor substrate 50 are fixed together using screws B3. As a result, the entire Z-axis angular velocity sensor 7Z is embedded in the uncured first filling member 91, and approximately the lower halves of the X-axis and Y-axis angular velocity sensors 7X and 7Y are also embedded.

[0060] ≪Third curing step S17≫ In the third curing step S17, the first filling member 91 filled in the recess 32 is heated and cured, thereby forming the filling member 9.

[0061] <Case installation process S18> In the case mounting step S18, as shown in Fig. 16, the outer case 4 is placed over the inner case 3. Then, the inner case 3 and the outer case 4 are fixed together using screws B1.

[0062] The sensor module 1 is obtained in this manner. This manufacturing method allows the sensor module 1 to be manufactured through simple steps. In particular, by configuring the recess 32 so that only the first filling member 91, which is filled last, comes into contact with the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z, the other second and third filling members 92 and 93 can be hardened in advance. This prevents the first, second, and third filling members 91, 92, and 93 from mixing with each other during manufacturing. This effectively suppresses fluctuations in the loss coefficient η of the first, second, and third filling members 91, 92, and 93.

[0063] The sensor module 1 of this embodiment has been described above. As described above, the sensor module 1 includes a sensor substrate 50 having an X-axis angular velocity sensor 7X as a first inertial sensor driven at a first drive frequency f1, a Y-axis angular velocity sensor 7Y as a second inertial sensor driven at a second drive frequency f2 different from the first drive frequency f1, and a substrate 5 on which the X-axis angular velocity sensor 7X and the Y-axis angular velocity sensor 7Y are mounted, a case 2 that covers the X-axis angular velocity sensor 7X and the Y-axis angular velocity sensor 7Y, and a filler member 9 that fills the space between the case 2 and the sensor substrate 50 and covers at least a portion of the X-axis angular velocity sensor 7X and the Y-axis angular velocity sensor 7Y. The filler member 9 includes a first filler member 91 that includes the first drive frequency f1 within a range of the full width at half maximum W11 of the loss factor η, and a second filler member 92 that includes the second drive frequency f2 within a range of the full width at half maximum W21 of the loss factor η. With this configuration, the first filling member 91 can effectively damp vibrations of the X-axis angular velocity sensor 7X, and the second filling member 92 can effectively damp vibrations of the Y-axis angular velocity sensor 7Y. This effectively suppresses vibration leakage from the sensor module 1. Therefore, for example, as shown in FIG. 10 , when multiple sensor modules 1 are mounted on one substrate 100, interference between the sensor modules 1 via the substrate 100 can be effectively suppressed.

[0064] As described above, the first filling member 91 includes the first drive frequency f1 within the range of the half width at half maximum W12 of the loss factor η, and the second filling member 92 includes the second drive frequency f2 within the range of the half width at half maximum W22 of the loss factor η. With this configuration, the first filling member 91 can more effectively dampen the vibrations of the X-axis angular velocity sensor 7X, and the second filling member 92 can more effectively dampen the vibrations of the Y-axis angular velocity sensor 7Y. This makes it possible to more effectively suppress vibration leakage from the sensor module 1.

[0065] As described above, the first filling member 91 and the second filling member 92 are stacked in the thickness direction, i.e., the Z-axis direction, of the substrate 5. With this configuration, the first filling member 91 and the second filling member 92 can be formed in this order, which makes it easier to manufacture the sensor module 1.

[0066] As described above, one of the first filling member 91 and the second filling member 92, located on the substrate 5 side, is in contact with the X-axis angular velocity sensor 7X and the Y-axis angular velocity sensor 7Y, while the other, located on the opposite side of the substrate 5, is out of contact with the X-axis angular velocity sensor 7X and the Y-axis angular velocity sensor 7Y. In this embodiment, the first filling member 91 located on the substrate 5 side is in contact with the X-axis and Y-axis angular velocity sensors 7X and 7Y, while the second filling member 92 located on the opposite side of the substrate 5 is out of contact with the X-axis and Y-axis angular velocity sensors 7X and 7Y. This configuration allows the second filling member 92 to be cured before filling the uncured first filling member 91, thereby preventing the first and second filling members 91 and 92 from intermixing during manufacturing. This effectively prevents variations in the loss coefficient η of the first and second filling members 91 and 92.

[0067] As described above, the case 2 has a mounting surface F on which the substrate 5 is placed, and a recess 32 that is recessed from the mounting surface F and accommodates at least a portion of the X-axis angular velocity sensor 7X and the Y-axis angular velocity sensor 7Y. The recess 32 is filled with the filling member 9. This configuration can prevent the uncured filling member 9 from spreading during manufacturing, allowing the filling member 9 to be formed accurately and according to design.

[0068] As described above, the sensor substrate 50 further includes a Z-axis angular velocity sensor 7Z, which is a third inertial sensor mounted on the substrate 5 and driven at a third drive frequency f3 different from the first drive frequency f1 and the second drive frequency f2. The filler 9 covers at least a portion of the Z-axis angular velocity sensor 7Z. The filler 9 also includes a third filler 93 whose full width at half maximum W31 of the loss coefficient η includes the third drive frequency f3. This configuration allows the third filler 93 to effectively damp vibrations of the Z-axis angular velocity sensor 7Z. This effectively suppresses vibration leakage from the sensor module 1.

[0069] As described above, the third filling member 93 includes the third drive frequency f3 within the range of the half width at half maximum W33 of the loss coefficient η. With this configuration, the third filling member 93 can more effectively attenuate the vibration of the Z-axis angular velocity sensor 7Z. As a result, vibration leakage from the sensor module 1 can be more effectively suppressed.

[0070] Although the sensor module 1 according to the first embodiment has been described above, the configuration of the sensor module 1 is not particularly limited. For example, as shown in FIG. 17 , the first and second filling members 91 and 92 located at the top and center of the filling member 9 may be in contact with the X-axis, Y-axis, and Z-axis angular velocity sensors, and the third filling member 93 located at the bottom may not be in contact with the X-axis, Y-axis, and Z-axis angular velocity sensors. Alternatively, as shown in FIG. 18 , all of the first, second, and third filling members 91, 92, and 93 may be in contact with the X-axis, Y-axis, and Z-axis angular velocity sensors. The stacking order of the first, second, and third filling members 91, 92, and 93 is not particularly limited. For example, the second filling member 92 may be located in the uppermost layer, or the third filling member 93 may be located in the uppermost layer.

[0071] 19, the sensor substrate 50 may have an acceleration sensor 6 as a fourth inertial sensor mounted on the upper surface 5a of the substrate 5. The acceleration sensor 6 is a triaxial acceleration sensor that can independently detect acceleration in the X-axis direction, acceleration in the Y-axis direction, and acceleration in the Z-axis direction.

[0072] Second Embodiment Fig. 20 is an exploded perspective view showing a sensor module according to a second embodiment. Fig. 21 is a cross-sectional view of the sensor module as seen from the negative side in the Y-axis direction. Fig. 22 is a cross-sectional view of the sensor module as seen from the negative side in the X-axis direction. Fig. 23 is a flowchart showing the manufacturing process of the sensor module. Figs. 24 to 26 are cross-sectional views illustrating the manufacturing method of the sensor module.

[0073] The sensor module 1 of this embodiment is similar to the first embodiment described above, except for the configurations of the inner case 3 and the filling member 9. In the following description, the differences between this embodiment and the first embodiment will be mainly described, and a description of similar points will be omitted. In addition, in each drawing of this embodiment, the same reference numerals are used to designate the same components as those in the previously described embodiment.

[0074] 20, inner case 3 has a first wall portion 351 and a second wall portion 352 formed in recess 32 and erected from the bottom surface of recess 32. First wall portion 351 and second wall portion 352 separate recess 32 into first recess 321, second recess 322, and third recess 323. In plan view from the Z-axis direction, first recess 321 houses X-axis angular velocity sensor 7X, second recess 322 houses Y-axis angular velocity sensor 7Y, and third recess 323 houses Z-axis angular velocity sensor 7Z.

[0075] 21 and 22, approximately the lower half of X-axis angular velocity sensor 7X is housed in first recess 321, approximately the lower half of Y-axis angular velocity sensor 7Y is housed in second recess 322, and the entire Z-axis angular velocity sensor 7Z is housed in third recess 323. First recess 321 is filled with first filling member 91, and approximately the lower half of X-axis angular velocity sensor 7X is covered and sealed with first filling member 91. Second recess 322 is filled with second filling member 92, and approximately the lower half of Y-axis angular velocity sensor 7Y is covered and sealed with second filling member 92. Third recess 323 is filled with third filling member 93, and the entire Z-axis angular velocity sensor 7Z is covered and sealed with third filling member 93.

[0076] Even with this configuration, the vibrations of the X-axis angular velocity sensor 7X can be effectively damped by the first filling member 91, the vibrations of the Y-axis angular velocity sensor 7Y can be effectively damped by the second filling member 92, and the vibrations of the Z-axis angular velocity sensor 7Z can be effectively damped by the third filling member 93. Therefore, vibration leakage from the sensor module 1 can be more effectively suppressed.

[0077] In particular, in this embodiment, the first filling member 91 directly covers the X-axis angular velocity sensor 7X, the second filling member 92 directly covers the Y-axis angular velocity sensor 7Y, and the third filling member 93 directly covers the Z-axis angular velocity sensor 7Z, making the above-mentioned damping effect more pronounced.

[0078] Furthermore, in this embodiment, the first filling member 91 contacts only the X-axis angular velocity sensor 7X and does not contact the other Y-axis and Z-axis angular velocity sensors 7Y and 7Z. The second filling member 92 contacts only the Y-axis angular velocity sensor 7Y and does not contact the other X-axis and Z-axis angular velocity sensors 7X and 7Z. The third filling member 93 contacts only the Z-axis angular velocity sensor 7Z and does not contact the other X-axis and Y-axis angular velocity sensors 7X and 7Y. Therefore, the first filling member 91 can cover a wider area of ​​the X-axis angular velocity sensor 7X, the second filling member 92 can cover a wider area of ​​the Y-axis angular velocity sensor 7Y, and the third filling member 93 can cover a wider area of ​​the Z-axis angular velocity sensor 7Z. This makes the damping effect more pronounced.

[0079] The sensor module 1 has been described above. Next, a manufacturing method for the sensor module 1 will be described. As shown in Fig. 23, the manufacturing method for the sensor module 1 includes a filling step S21 of filling the recess 32 of the inner case 3 with first, second, and third filling members 91, 92, and 93, a sensor substrate mounting step S22 of mounting the sensor substrate 50 on the mounting surface F of the inner case 3, a curing step S23 of curing the first, second, and third filling members 91, 92, and 93, and a case mounting step S24 of mounting the outer case 4 to the inner case 3. Note that, because the manufacturing method will be described below using the cross section shown in Fig. 21, some components will be mentioned in the description but not shown.

[0080] ≪Filling process S21≫ 24, in the first filling step S21, uncured first, second, and third filling members 91, 92, and 93 are filled into the recess 32 of the inner case 3. Specifically, the uncured first filling member 91 is filled into the first recess 321, the uncured second filling member 92 is filled into the second recess 322, and the uncured third filling member 93 is filled into the third recess 323. Because the first, second, and third recesses 321, 322, and 323 are separated from each other, the uncured first, second, and third filling members 91, 92, and 93 will not mix with each other even if they are filled at the same time in this step.

[0081] <Sensor substrate placement step S22> 25, in the sensor substrate mounting process S22, the sensor substrate 50 is mounted on the mounting surface F of the inner case 3. Then, the inner case 3 and the sensor substrate 50 are fixed together using screws B3. As a result, approximately the lower half of the X-axis angular velocity sensor 7X is embedded in the uncured first filling member 91, approximately the lower half of the Y-axis angular velocity sensor 7Y is embedded in the uncured second filling member 92, and the entire Z-axis angular velocity sensor 7Z is embedded in the uncured third filling member 93.

[0082] ≪Curing process S23≫ In the hardening step S23, the first, second and third filling members 91, 92 and 93 are heated and hardened, thereby forming the filling member 9.

[0083] <Case installation process S24> In the case mounting step S24, as shown in Fig. 26, the outer case 4 is placed over the inner case 3. Then, the inner case 3 and the outer case 4 are fixed together using screws B1.

[0084] This completes the manufacturing process of the sensor module 1. According to this manufacturing method, the first, second, and third filling members 91, 92, and 93 are cured collectively in the curing step S23, and therefore the thermal history (thermal damage) of the sensor module 1 can be reduced compared to, for example, the first embodiment described above, where the first, second, and third filling members 91, 92, and 93 are cured in three separate steps.

[0085] As described above, in the sensor module 1 of this embodiment, the first filling member 91 contacts the X-axis angular velocity sensor 7X, and the second filling member 92 contacts the Y-axis angular velocity sensor 7Y. With this configuration, the first filling member 91 can effectively dampen vibrations of the X-axis angular velocity sensor 7X, and the second filling member 92 can effectively dampen vibrations of the Y-axis angular velocity sensor 7Y. This makes it possible to more effectively suppress vibration leakage from the sensor module 1.

[0086] As described above, the first filling member 91 is out of contact with the Y-axis angular velocity sensor 7Y, and the second filling member 92 is out of contact with the X-axis angular velocity sensor 7X. With this configuration, the first filling member 91 can cover a wider area of ​​the X-axis angular velocity sensor 7X, and the second filling member 92 can cover a wider area of ​​the Y-axis angular velocity sensor 7Y. Therefore, the first filling member 91 can more effectively dampen vibrations of the X-axis angular velocity sensor 7X, and the second filling member 92 can more effectively dampen vibrations of the Y-axis angular velocity sensor 7Y.

[0087] As described above, the case 2 has a mounting surface F on which the substrate 5 is placed and a recess 32 that is recessed from the mounting surface F and accommodates at least a portion of the X-axis angular velocity sensor 7X and the Y-axis angular velocity sensor 7Y. The recess 32 also has a first recess 321 that accommodates at least a portion of the X-axis angular velocity sensor 7X and a second recess 322 that is formed separately from the first recess 321 and accommodates at least a portion of the Y-axis angular velocity sensor 7Y. The first recess 321 is filled with a first filling member 91, and the second recess 322 is filled with a second filling member 92. This simple configuration allows the first filling member 91 to be disposed in a non-contact state with the Y-axis angular velocity sensor 7Y, and the second filling member 92 to be disposed in a non-contact state with the X-axis angular velocity sensor 7X.

[0088] The second embodiment can also achieve the same effects as the first embodiment described above.

[0089] <Third embodiment> FIG. 27 is a cross-sectional view showing the inside of the sensor module according to the third embodiment, as viewed from the positive side in the Z axis direction.

[0090] The sensor module 1 of this embodiment is similar to the first embodiment described above, except for the configuration of the sensor substrate 50. In the following description, the differences between this embodiment and the first embodiment will be mainly described, and a description of similar points will be omitted. In addition, in the drawings of this embodiment, the same reference numerals are used to designate similar components to those in the previously described embodiment.

[0091] 27, the sensor substrate 50 of this embodiment has two X-axis angular velocity sensors 7X1 and 7X2, two Y-axis angular velocity sensors 7Y1 and 7Y2, and two Z-axis angular velocity sensors 7Z1 and 7Z2. By arranging two angular velocity sensors for each axis in this way, noise is reduced and the angular velocity detection accuracy of the sensor module 1 is improved.

[0092] The two X-axis angular velocity sensors 7X1 and 7X2 are arranged side by side on the first side surface 5c of the substrate 5, and approximately the lower half of each is covered and sealed with the filling member 9. The two Y-axis angular velocity sensors 7Y1 and 7Y2 are arranged side by side on the second side surface 5d of the substrate 5, and approximately the lower half of each is covered and sealed with the filling member 9. The two Z-axis angular velocity sensors 7Z1 and 7Z2 are arranged side by side on the lower surface 5b of the substrate 5, and each is entirely covered and sealed with the filling member 9.

[0093] In this embodiment, the first drive frequencies f1 of the X-axis angular velocity sensors 7X1 and 7X2 are made different from each other to suppress interference between the X-axis angular velocity sensors 7X1 and 7X2. The second drive frequencies f2 of the Y-axis angular velocity sensors 7Y1 and 7Y2 are made different from each other to suppress interference between the Y-axis angular velocity sensors 7Y1 and 7Y2. In contrast, the third drive frequencies f3 of the Z-axis angular velocity sensors 7Z1 and 7Z2 are the same, but by arranging them as far apart as possible, interference between the Z-axis angular velocity sensors 7Z1 and 7Z2 is suppressed.

[0094] For example, the first drive frequency f1 of X-axis angular velocity sensor 7X1 and the second drive frequency f2 of Y-axis angular velocity sensor 7Y2 can be set in the range of 48.5 to 50.0 kHz, the first drive frequency f1 of X-axis angular velocity sensor 7X2 and the second drive frequency f2 of Y-axis angular velocity sensor 7Y1 can be set in the range of 50.5 to 52.0 kHz, and the third drive frequency f3 of Z-axis angular velocity sensors 7Z1 and 7Z2 can be set in the range of 52.5 to 54.0 kHz. In this case, the first filler 91 can dampen the vibrations of X-axis angular velocity sensor 7X1 and Y-axis angular velocity sensor 7Y2, the second filler 92 can dampen the vibrations of X-axis angular velocity sensor 7X2 and Y-axis angular velocity sensor 7Y1, and the third filler 93 can dampen the vibrations of Z-axis angular velocity sensors 7Z1 and 7Z2.

[0095] The third embodiment as described above can also achieve the same effects as the first embodiment.

[0096] However, the configuration of the sensor module 1 is not particularly limited. For example, the first drive frequency f1 of the X-axis angular velocity sensors 7X1 and 7X2 may be the same, the second drive frequency f2 of the Y-axis angular velocity sensors 7Y1 and 7Y2 may be the same, and the third drive frequency f3 of the Z-axis angular velocity sensors 7Z1 and 7Z2 may be the same. In this case, for example, the first drive frequency f1 of the X-axis angular velocity sensors 7X1 and 7X2 may be within the range of 48.5 to 50.0 kHz, the second drive frequency f2 of the Y-axis angular velocity sensors 7Y1 and 7Y2 may be within the range of 50.5 to 52.0 kHz, and the third drive frequency f3 of the Z-axis angular velocity sensors 7Z1 and 7Z2 may be within the range of 52.5 to 54.0 kHz or 53.0 kHz. In other words, angular velocity sensors having the same drive frequency may be arranged adjacent to each other. Even with this configuration, the first filling member 91 can dampen the vibrations of the X-axis angular velocity sensors 7X1 and 7X2, thereby effectively suppressing interference between the X-axis angular velocity sensors 7X1 and 7X2. The second filling member 92 can dampen the vibrations of the Y-axis angular velocity sensors 7Y1 and 7Y2, thereby effectively suppressing interference between the Y-axis angular velocity sensors 7Y1 and 7Y2. The third filling member 93 can dampen the vibrations of the Z-axis angular velocity sensors 7Z1 and 7Z2, thereby effectively suppressing interference between the Z-axis angular velocity sensors 7Z1 and 7Z2.

[0097] <Fourth embodiment> Fig. 28 is an exploded perspective view showing a sensor module according to the fourth embodiment, and Fig. 29 is a cross-sectional view of the sensor module as seen from the negative side in the Y-axis direction.

[0098] The sensor module 1 of this embodiment is similar to the first embodiment described above, except that the configurations of the case 2 and the sensor substrate 50 are different. In the following description, the differences between this embodiment and the first embodiment will be mainly described, and a description of similar points will be omitted. In addition, in each drawing of this embodiment, the same reference numerals are used to designate the same components as those in the previously described embodiment.

[0099] As shown in FIG. 28, the case 2 of this embodiment is composed only of a box-shaped outer case 4. Meanwhile, the sensor board 50 includes a board 5 and an X-axis angular velocity sensor 7X, a Y-axis angular velocity sensor 7Y, and a Z-axis angular velocity sensor 7Z mounted on an upper surface 5a of the board 5. The sensor board 50 is inserted into the outer case 4 with its upper surface 5a facing the outer case 4. As shown in FIG. 29, the outer case 4 is filled with a filler 9 that covers the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z. Terminals (not shown) electrically connected to the X-axis, Y-axis, and Z-axis angular velocity sensors 7X, 7Y, and 7Z are formed on the lower surface 5b of the board 5, and the board 5 can be electrically connected to an external device via these terminals.

[0100] The fourth embodiment can also achieve the same effects as the first embodiment described above.

[0101] Although the sensor module of the present invention has been described above based on the illustrated embodiment, the present invention is not limited to this, and the configuration of each part can be replaced with any configuration having a similar function. Furthermore, any other configuration may be added to the present invention. Furthermore, each embodiment may be combined as appropriate. [Explanation of symbols]

[0102] 1...sensor module, 100...board, 2...case, 3...inner case, 31...screw hole, 32...recess, 321...first recess, 322...second recess, 323...third recess, 33...through hole, 34...screw hole, 351...first wall portion, 352...second wall portion, 4...outer case, 41...screw insertion hole, 42...screw insertion hole, 43...recess, 5...board, 5a...upper surface, 5b...lower surface, 5c...first side surface, 5d...second side surface, 50...sensor board, 51...circuit element child, 52...connector, 54...screw insertion hole, 6...accelerometer, 7X...X-axis angular velocity sensor, 7X1...X-axis angular velocity sensor, 7X2...X-axis angular velocity sensor, 7Y...Y-axis angular velocity sensor, 7Y1...Y-axis angular velocity sensor, 7Y2...Y-axis angular velocity sensor, 7Z...Z-axis angular velocity sensor, 7Z1...Z-axis angular velocity sensor, 7Z2...Z-axis angular velocity sensor, 71...package, 72...base, 721...recess, 73...lid, 74...sensor Element, 740...base, 741...detection vibration arm, 742...drive vibration arm, 75...support substrate, 9...filler, 91...first filling member, 92...second filling member, 93...third filling member, B1...screw, B2...screw, B3...screw, F...mounting surface, J...detection axis, R...seal ring, S11...first filling step, S12...first hardening step, S13...second filling step, S14...second hardening step, S15...third filling step, S16...sensor substrate mounting step, S17...third Curing process, S18...case mounting process, S21...filling process, S22...sensor substrate mounting process, S23...curing process, S24...case mounting process, W11...full width at half maximum, W12...half width at half maximum, W21...full width at half maximum, W22...half width at half maximum, W31...full width at half maximum, W32...half width at half maximum, W33...half width at half maximum, f1...first drive frequency, f2...second drive frequency, f3...third drive frequency, p...peak, ω...angular velocity, ωx...angular velocity, ωy...angular velocity, ωz...angular velocity

Claims

1. a sensor substrate including a first inertial sensor driven at a first drive frequency, a second inertial sensor driven at a second drive frequency different from the first drive frequency, and a substrate on which the first inertial sensor and the second inertial sensor are mounted; a case that covers the first inertial sensor and the second inertial sensor; a filling member that is filled between the case and the sensor substrate and that covers at least a portion of each of the first inertial sensor and the second inertial sensor, the filling member includes a first filling member that includes the first drive frequency within a full width at half maximum range of a loss factor, and a second filling member that includes the second drive frequency within a full width at half maximum range of a loss factor.

2. the first filling member includes the first driving frequency within a range of half width at half maximum of a loss factor, The sensor module according to claim 1 , wherein the second filling member has the second drive frequency within a range of half width at half maximum of the loss factor.

3. The sensor module according to claim 1 , wherein the first filling member and the second filling member are stacked in a thickness direction of the substrate.

4. 4. The sensor module of claim 3, wherein one of the second filling member and the first filling member, located on the substrate side, is in contact with the first inertial sensor and the second inertial sensor, and the other, located on the opposite side of the substrate, is not in contact with the first inertial sensor and the second inertial sensor.

5. the case has a mounting surface on which the substrate is mounted, and a recess recessed from the mounting surface and accommodating at least a portion of the first inertial sensor and at least a portion of the second inertial sensor; The sensor module according to claim 4 , wherein the recess is filled with the filling member.

6. the first filler member is in contact with the first inertial sensor; The sensor module according to claim 1 , wherein the second filler member is in contact with the second inertial sensor.

7. the first filling member is in non-contact with the second inertial sensor; The sensor module according to claim 6 , wherein the second filling member is not in contact with the first inertial sensor.

8. the case has a mounting surface on which the substrate is mounted, and a recess recessed from the mounting surface and accommodating at least a portion of the first inertial sensor and at least a portion of the second inertial sensor; the recess includes a first recess accommodating at least a portion of the first inertial sensor, and a second recess formed separately from the first recess and accommodating at least a portion of the second inertial sensor; The first recess is filled with the first filling member, The sensor module according to claim 7 , wherein the second recess is filled with the second filling member.

9. the sensor substrate further includes a third inertial sensor mounted on the substrate and driven at a third drive frequency different from the first drive frequency and the second drive frequency; the filler member covers at least a portion of the third inertial sensor; The sensor module of claim 1 , wherein the filler member includes a third filler member having a full width at half maximum loss factor that includes the third drive frequency.

10. The sensor module according to claim 9 , wherein the third filling member includes the third drive frequency within a range of half width at half maximum of a loss factor.

Images