Sensor module and electronic device

Abstract

To provide a sensor module capable of improving effectiveness and reliability of increased precision of detection data.SOLUTION: A sensor module 100 includes a board 21, a board 22, and a flexible board 40 for connecting the board 21 and the board 22. The board 21 includes a sensor device 11a for detecting an angular velocity around the Z axis, a sensor device 12a for detecting an angular velocity around the X axis, and a sensor device 13a for detecting an angular velocity around the Y axis. The board 22 includes a sensor device 11b for detecting the angular velocity around the Z axis, a sensor device 12b for detecting the angular velocity around the X axis, and a sensor device 13b for detecting the angular velocity around the Y axis.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a sensor module and an electronic device.

Background Art

[0002] A sensor module that attempts to improve the accuracy of X-axis angular velocity data by mounting two X-axis angular velocity sensor devices on the side surface of the same substrate is described in Patent Document 1.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a sensor module including a plurality of sensor devices with respect to one detection axis, further improvements are desired in the effectiveness and reliability of accuracy improvement.

Means for Solving the Problems

[0005] A sensor module according to one aspect of the present application includes a first substrate, a second substrate, and a connection portion that connects between the first substrate and the second substrate. The first substrate includes a first sensor device that detects a physical quantity of a first axis, a second sensor device that detects a physical quantity of a second axis, and a third sensor device that detects a physical quantity of a third axis. The second substrate includes a fourth sensor device that detects a physical quantity of the first axis, a fifth sensor device that detects a physical quantity of the second axis, and a sixth sensor device that detects a physical quantity of the third axis.

[0006] An electronic device according to one aspect of the present application includes the sensor module described above.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8A

Figure 8B

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

MODE FOR CARRYING OUT THE INVENTION

[0008] In each drawing, for ease of viewing each component, the scale of the dimensions may be shown differently depending on the component. In each drawing, the X-axis, Y-axis, and Z-axis are orthogonal to each other. In the following description, the "X-axis direction" indicates a direction parallel to the X-axis, the "Y-axis direction" indicates a direction parallel to the Y-axis, and the "Z-axis direction" indicates a direction parallel to the Z-axis. In the following description, the "plus side" indicates the tip side in the arrow direction of each axis of XYZ, and the "minus side" indicates the end side in the arrow direction. In the following description, "plan view" refers to viewing from the Z-axis direction with respect to the plane including the X-axis and Y-axis, and "cross-sectional view" refers to viewing from the X-axis direction or Y-axis direction with respect to the cross-section including the Z-axis.

[0009] In the following description, the description of the upper surface of a certain configuration shall indicate the surface on the plus side in the Z-axis direction of the said configuration. For example, "the upper surface of the substrate" shall indicate the surface on the plus side in the Z-axis direction of the substrate. In the following description, the description of the lower surface of a certain configuration shall indicate the surface on the minus side in the Z-axis direction of the said configuration.

[0010] 1. Embodiment 1 Figures 1 to 11 show the sensor module 100 according to Embodiment 1. Figure 1 is a perspective view showing a state where the sensor module 100 is fixed to a mounting surface 71 such as an automobile. Figure 2 is a perspective view showing the state of the sensor module 100 in Figure 1 viewed from the mounting surface 71 side. Figure 3 is an exploded perspective view of the sensor module 100. Figure 4 is a developed view of the substrate unit 20. Figure 5 is a developed view of the substrate unit 20. Figure 6 is an enlarged view of the P view in Figure 4. Figure 7 is a perspective view of the fixing frame 60. Figure 8A is a cross-sectional view taken along the line A-A in Figure 6, showing an example of the sensor device 12b. Figure 8B is a cross-sectional view taken along the line A-A in Figure 6, showing another example of the sensor device 12b. Figure 9 is an explanatory view showing the internal configuration of the sensor device. Figure 10 is a perspective view of a modified example of the sensor device. Figure 11 is a developed view of a modified example of the substrate unit 20.

[0011] In the present embodiment, the sensor module 100 is an inertial measurement unit (IMU) that detects the posture and behavior of a mounting device such as an automobile or a robot. Here, the mounting device can be referred to as a moving body. The behavior can be referred to as inertial momentum.

[0012] As shown in FIG. 1, the sensor module 100 has an outer case 50 with a substantially square planar shape and a rectangular parallelepiped three-dimensional shape. The size of the sensor module 100 is, for example, about 24 mm in length of one side of the square and about 10 mm in thickness.

[0013] Inside the outer case 50, a substrate unit 20 on which a plurality of sensor devices are mounted is housed. The substrate unit 20 will be described later. On the lower surface 58 of the outer case 50, screw holes 52 are formed. By passing screws 70 through these two screw holes 52, the sensor module 100 is fixed to the mounting surface 71 of a mounted device such as an automobile and used.

[0014] As shown in FIG. 2, an inner case 30 is housed inside the upper surface 57 of the outer case 50. An opening 31 is formed on the upper surface 34 of the inner case 30. Inside the opening 31, a plug-type connector 15 is arranged.

[0015] The connector 15 has a plurality of pins. A socket-type connector (not shown) is connected to the connector 15 from the mounted device. The sensor module 100 is supplied with power from the power circuit of the mounted device via the connector 15 and transmits electrical signals such as detection data to the mounted device.

[0016] 1.1. Configuration of Sensor Module FIG. 3 is an exploded perspective view of the sensor module 100 shown in FIG. 2. As shown in FIG. 3, the sensor module 100 is composed of an outer case 50 and a sensor unit 10 housed in the outer case 50.

[0017] The outer case 50 is a pedestal cut out in a box shape from aluminum. The material is not limited to aluminum, and other metals such as zinc and stainless steel, resins, or composite materials of metal and resin may also be used.

[0018] The outer case 50 is in the shape of a lidless box, and its inner side 53 forms an internal space surrounded by a bottom surface 55 and side walls 54. In the internal space of the outer case 50, the sensor unit 10 is accommodated via a joining member.

[0019] The sensor unit 10 is composed of an inner case 30 and a substrate unit 20 accommodated in the inner case 30. The inner case 30 is a member that holds the substrate unit 20 and is shaped to fit inside the inner side 53 of the outer case 50. In plan view, the inner case 30 is an octagon with the corners of the four vertices of a square chamfered, and an opening 31 which is a through-hole and a recess 33 are formed on its upper surface.

[0020] The height of the side wall 32 of the inner case 30 is lower than the height of the side wall 54 of the outer case 50, and as shown in FIG. 2, the upper surface 34 of the inner case 30 is lower than the upper surface 57 of the outer case 50. Although not shown, guide pins and support surfaces for positioning the substrate unit 20 are formed inside the inner case 30. The substrate unit 20 is positioned by the guide pins and support surfaces and is fixed inside the inner case 30 by a joining member.

[0021] 1.2. Configuration of the Substrate Unit FIG. 4 is a development view showing the substrate unit 20 in a developed state, and is a view showing the main surface f1 side of the substrate 21 and the main surface f2 side of the substrate 22. FIG. 5 is a development view of the substrate unit 20 seen from the opposite side of FIG. 4, and is a view showing the upper surface fu1 side of the substrate 21 and the lower surface fd2 side of the substrate 22. In FIGS. 4 and 5, the coordinate axes indicating the X-axis, Y-axis, and Z-axis show the coordinate axes in the assembled state of the substrate unit 20, and the directions of the coordinate axes are different between the substrate 21 and the substrate 22. As shown in FIGS. 3 and 7, the substrate unit 20 is used in an assembled state. In the present embodiment, the substrate unit 20 is supported by a fixing frame 60 and assembled into a substantially rectangular parallelepiped shape.

[0022] In this embodiment, the substrate unit 20 includes substrates 21 and 22, a flexible substrate 40, sensor devices 11a, 12a, 13a, 11b, 12b, 13b, an arithmetic circuit 14, a connector 15, a memory 16, a power supply circuit 17, and a temperature sensor 18.

[0023] The substrates 21 and 22 are rigid substrates called rigid boards. Specifically, they are glass epoxy substrates. The substrates 21 and 22 may be rigid boards such as composite substrates or ceramic substrates. The substrates 21 and 22 may have either a multilayer or a single-layer structure.

[0024] The flexible substrate 40 is a substrate softer than the substrates 21 and 22. The flexible substrate 40 is disposed between the substrates 21 and 22 and electrically connects the substrates 21 and 22. In this embodiment, the flexible substrate 40 is used to suppress the occurrence of mechanical or electrical interference generated between a plurality of sensor devices. The flexible substrate 40 may be a wiring cable, a wiring cord, or a wire having flexibility such as a flat cable or a flat cord.

[0025] The substrates 21, 22, and the flexible substrate 40 may be rigid-flexible substrates. When a rigid-flexible substrate is adopted, the rigid-flexible substrate includes two rigid parts and one flexible part. In this embodiment, the two rigid parts respectively correspond to the substrates 21 and 22, and the one flexible part corresponds to the flexible substrate 40.

[0026] On the upper surface fu1 of the substrate 21, the arithmetic circuit 14, the connector 15, the memory 16, the power supply circuit 17, and the temperature sensor 18 are mounted. Other electronic components are mounted on the upper surface fu1 of the substrate 21.

[0027] The arithmetic circuit 14 is the primary controller for the sensor devices 11a, 12a, 13a, 11b, 12b, and 13b. The arithmetic circuit 14 is an integrated circuit device and can be realized by a processor such as an MPU (Micro Processor Unit) or a CPU (central processing unit).

[0028] The arithmetic circuit 14 receives the detection data output from the sensor devices 11a, 12a, 13a, 11b, 12b, and 13b, performs various processes, and transmits the processed detection data externally via the connector 15.

[0029] The various processes performed by the arithmetic circuit 14 include processes for obtaining the average value of the detection data of the angular velocity around each Z-axis from the sensor device 11a and the sensor device 11b, processes for obtaining the average value of the detection data of the angular velocity around each X-axis from the sensor device 12a and the sensor device 12b, processes for obtaining the average value of the detection data of the angular velocity around each Y-axis from the sensor device 13a and the sensor device 13b, processes for performing temperature correction, zero-point correction, etc. on the obtained average values, sensitivity adjustment processes, filter processes, and processes for outputting the processed detection data from the connector 15. The arithmetic circuit 14 is an example of a processing unit. The process of obtaining the average value of the angular velocity around each axis is an example of a desired process.

[0030] The connector 15 is a plug-type connector and has two rows of connection terminals arranged at equal pitches in the Y-axis direction. In this embodiment, the connector 15 has 10 pins in one row and a total of 20 connection terminals, but the number of terminals may be appropriately changed according to the design specifications.

[0031] The memory 16 stores programs for executing various processes performed by the arithmetic circuit 14, programs for incorporating the processed detection data into packet data, and data necessary for the execution of the programs, such as table data used for temperature correction processing.

[0032] The power supply circuit 17 is supplied with power from the device to be worn and supplies the necessary power to the sensor devices 11a, 12a, 13a, 11b, 12b, 13b, the arithmetic circuit 14, and the like. The temperature sensor 18 outputs temperature information used for temperature correction processing to the arithmetic circuit 14.

[0033] 1.3. Regarding the sensor device In the present embodiment, the sensor devices 11a, 11b, 12a, 12b, 13a, 13b are vibration gyro sensors that use quartz as a vibrator and detect the angular velocity from the Coriolis force applied to the vibrator. The vibrator is not limited to quartz. For example, the vibrator may be a MEMS (Micro Electro Mechanical Systems) vibrator formed using a silicon substrate.

[0034] The sensor devices 11a and 11b are Z-axis angular velocity sensors that respectively detect the angular velocity around the Z-axis. The drive frequencies of the sensor device 11a and the sensor device 11b are the same, for example, 49.6 kHz. The drive frequencies of the sensor devices 11a and 11b are an example of the first drive frequency. The drive frequency will be described in Section 1.7.2.

[0035] The sensor devices 12a and 12b are X-axis angular velocity sensors that respectively detect the angular velocity around the X-axis. The drive frequencies of the sensor device 12a and the sensor device 12b are the same, for example, 51.0 kHz. The drive frequencies of the sensor devices 12a and 12b are an example of the second drive frequency.

[0036] The sensor devices 13a and 13b are Y-axis angular velocity sensors that respectively detect the angular velocity around the Y-axis. The drive frequencies of the sensor device 13a and the sensor device 13b are the same, for example, 53.6 kHz. The drive frequencies of the sensor devices 13a and 13b are an example of the third drive frequency.

[0037] The sensor devices 11a, 12a, and 13a are mounted on the main surface f1 of the substrate 21. The sensor devices 11b, 12b, and 13b are mounted on the main surface f2 of the substrate 22. In other words, the substrate 21 mounts three sensor devices 11a, 12a, and 13a with different driving frequencies respectively, and the substrate 22 mounts three sensor devices 11b, 12b, and 13b with different driving frequencies respectively.

[0038] The sensor module 100 of the present embodiment includes two Z-axis angular velocity sensors, two X-axis angular velocity sensors, and two Y-axis angular velocity sensors respectively, thereby realizing high-precision angular velocity data for each axis. Furthermore, the angular velocity sensors of the same axis are provided separately on the substrate 21 and the substrate 22. Therefore, it is possible to suppress the interference between the angular velocity sensors of the same axis, and improve the effectiveness of high-precision angular velocity data for each axis. Furthermore, the driving frequencies of the three angular velocity sensors provided on the substrate 21 are different from each other. Similarly, the driving frequencies of the three angular velocity sensors provided on the substrate 22 are different from each other. Therefore, it is possible to suppress the interference between the three angular velocity sensors provided on each of the substrates 21 and 22, and improve the effectiveness of high-precision angular velocity data for each axis.

[0039] Furthermore, the driving frequencies of the two Z-axis angular velocity sensors are the same. Therefore, the sensor module 100 of the present embodiment can reduce the costs required to prepare the sensor device 11a and the sensor device 11b with different driving frequencies, for example, costs in manufacturing, ordering, inventory, or assembly, etc., and can improve the industrial utility value. The same applies to the X-axis angular velocity sensor and the Y-axis angular velocity sensor.

[0040] 1.4. About the relay substrate As shown in FIG. 6, the sensor device 12b is mounted on the main surface f2 of the substrate 22 in a state of being mounted on the relay substrate 25c. The relay board 25c is a board sized slightly larger than the sensor device 12b with a rectangular planar shape, and is arranged perpendicular to the board 22. As the relay board 25c, a rigid board such as a glass epoxy board is used, similar to the board 22.

[0041] The sensor device 12b is mounted on the + side surface of the relay board 25c in the X-axis direction, and a plurality of pin headers 27 are mounted on the - side surface of the relay board 25c in the X-axis direction. The pin header 27 is a metal rod-shaped component for connecting between two boards. The ends of the pins are inserted into the via holes of the board 22 and soldered.

[0042] The relay board 25c is mounted in a state of standing on the board 22 by a plurality of pin headers 27. The relay board 25c is arranged such that the extending direction of the long side of the rectangle is parallel to the Y-axis direction. Thereby, the sensor device 12b is arranged in a state orthogonal to the X-axis direction of the detection axis.

[0043] The plurality of pin headers 27 also serve as electrical wiring between the relay board 25c and the board 22. The detection data and drive voltage of the sensor device 12b are transmitted and received to and from the board 22 via the plurality of pin headers 27. The pin header 27 can be replaced by a method that can mount the relay board 25c perpendicularly to the board 22. The pin header 27 may be replaced by a configuration in which mounting terminals are provided on the side surface of the relay board 25c or an L-shaped connection fitting or the like.

[0044] The sensor device 13b is arranged on the main surface f2 of the board 22 in a state of being mounted on the relay board 25d. The relay board 25d is the same board as the relay board 25c and is arranged perpendicular to the board 22. The relay board 25d is mounted in a state of standing on the board 22 by a plurality of pin headers 27. The relay board 25d is arranged such that the extending direction of the long side of the rectangle is parallel to the X-axis direction. Thereby, the sensor device 13b is arranged in a state orthogonal to the Y-axis direction of the detection axis.

[0045] The sensor device 12a is disposed on the main surface f1 of the substrate 21 while being mounted on the relay substrate 25a. The relay substrate 25a is a substrate similar to the relay substrate 25c and is disposed perpendicular to the substrate 21. The relay substrate 25a is mounted on the substrate 21 in an erected state by a plurality of pin headers 27. The relay substrate 25a is disposed such that the extending direction of the long side of the rectangle is parallel to the Y-axis direction. Thereby, the sensor device 12a is disposed in a state orthogonal to the X-axis direction of the detection axis.

[0046] The sensor device 13a is disposed on the main surface f1 of the substrate 21 while being mounted on the relay substrate 25b. The relay substrate 25b is a substrate similar to the relay substrate 25c and is disposed perpendicular to the substrate 21. The relay substrate 25b is mounted on the substrate 21 in an erected state by a plurality of pin headers 27. The relay substrate 25b is disposed such that the extending direction of the long side of the rectangle is parallel to the X-axis direction. Thereby, the sensor device 13a is disposed in a state orthogonal to the Y-axis direction of the detection axis.

[0047] In the present embodiment, the substrate 21 is an example of a first substrate, and the main surface f1 is an example of a first surface. The substrate 22 is an example of a second substrate, and the main surface f2 is an example of a second surface. The sensor device 11a is an example of a first sensor device, and the angular velocity around the Z-axis is an example of a physical quantity of a first axis. The sensor device 12a is an example of a second sensor device, and the angular velocity around the X-axis is an example of a physical quantity of a second axis. The sensor device 13a is an example of a third sensor device, and the angular velocity around the Y-axis is an example of a physical quantity of a third axis. The sensor device 11b is an example of a fourth sensor device, the sensor device 12b is an example of a fifth sensor device, and the sensor device 13b is an example of a sixth sensor device. The arithmetic circuit 14 is an example of a processing unit. The relay substrate 25a is an example of a first relay substrate, the relay substrate 25b is an example of a second relay substrate, the relay substrate 25c is an example of a third relay substrate, and the relay substrate 25d is an example of a fourth relay substrate.

[0048] 1.5. About the fixing frame FIG. 7 is a perspective view of the fixing frame 60, showing the fixing frame 60 with the substrate unit 20 attached. In FIG. 7, the substrate 21 is omitted for the sake of explanation. The fixing frame 60 has an octagonal cylindrical shape in plan view. On the upper surface 61 of the fixing frame 60, the substrate 21 is attached so as to close the opening 68 on the plus side in the Z-axis direction, and on the lower surface 62 of the fixing frame 60, the substrate 22 is attached so as to close the opening 68 on the minus side in the Z-axis direction.

[0049] The main surface f1 of the substrate 21 and the main surface f2 of the substrate 22 are arranged to face each other. The sensor devices 11a, 12a, 13a, 11b, 12b, and 13b are provided between the substrate 21 and the substrate 22, thereby improving the shielding performance against external noise.

[0050] The fixing frame 60 is formed of, for example, resin. The elastic modulus of the fixing frame 60 is preferably smaller than those of the substrates 21 and 22 and larger than that of the flexible substrate 40.

[0051] By making the elastic modulus of the fixing frame 60 smaller than those of the substrates 21 and 22, mechanical or electrical interference generated by operating the sensor devices 11a, 12a, 13a and the sensor devices 11b, 12b, 13b simultaneously can be suppressed.

[0052] By making the elastic modulus of the fixing frame 60 larger than that of the flexible substrate 40, the substrates 21 and 22 can be fixed at desired positions corresponding to the detection axes of the mounted sensor devices, and displacement from the desired positions can be suppressed.

[0053] In the present embodiment, the substrate unit 20 is fixed to the fixing frame 60 during assembly, but the substrate unit 20 is not limited to the form using the fixing frame 60. For example, the substrate unit 20 may be directly fixed to the inner case 30 without using the fixing frame 60.

[0054] 1.6. Packaging Figures 8A and 8B are cross-sectional views taken along line A-A of Figure 6, and are diagrams for explaining the packaging of the sensor device 12b. In the present embodiment, the sensor device 12b in Figure 8A is a physical quantity sensor that detects the angular velocity around the X-axis. The sensor device 12b in Figure 8B is a composite physical quantity sensor that detects the angular velocity around the X-axis and the acceleration in the X-axis direction.

[0055] As shown in Figures 8A and 8B, the sensor device 12b includes a package 7, a sensor element 3 and a circuit element 4 housed in the package 7, or sensor elements 3a, 3b and a circuit element 4. Although not shown, the sensor devices 11a, 12a, 13a, 11b, 13b also have the same configuration as the sensor device 12b.

[0056] The package 7 includes a base 5 having a recess that opens on the positive side in the X-axis direction, and a lid 6 that is joined to the base 5 via a joining member so as to close the opening of the recess. An internal space S is formed inside the package 7 by the recess.

[0057] The package 7 is, for example, a ceramic package. The base 5 is made of ceramics such as alumina, and the lid 6 is made of ceramics such as alumina or a metal material such as kovar.

[0058] The sensor device 12b in Figure 8A houses the sensor element 3 and the circuit element 4 in the internal space S. The sensor element 3 is an angular velocity sensor that detects the angular velocity around the X-axis, and includes a vibrator 1 and a support substrate 2. The vibrator 1 is a crystal vibrator. The circuit element 4 includes a detection circuit and the like, which will be described later.

[0059] The internal space S is airtight and is in a depressurized state, preferably a state closer to a vacuum. Thereby, the vibration characteristics of the vibrator 1 are improved. However, the atmosphere of the internal space S is not particularly limited.

[0060] In the internal space S, the vibrator 1, the support substrate 2, and the circuit element 4 are arranged so as to overlap each other in a plan view. Such an arrangement can suppress the spread of the planar area of the package 7 in the Y-axis direction and / or the Z-axis direction, and can achieve miniaturization of the sensor device 12b.

[0061] A plurality of internal terminals 8a, 8b are provided in the recess of the base 5, and a plurality of external terminals 8c are provided on the surface of the base 5 on the minus side in the X-axis direction. These internal terminals 8a, 8b and external terminals 8c are electrically connected to wirings (not shown) formed in the base 5 and the relay substrate 25c. The internal terminal 8a is electrically connected to the sensor element 3 via a conductive bonding member, and the internal terminal 8b is electrically connected to the circuit element 4 via a bonding wire 9.

[0062] The sensor device 12b in FIG. 8B houses the sensor elements 3a, 3b and the circuit element 4 in the internal space S. The sensor element 3a is an angular velocity sensor that detects the angular velocity around the X-axis. Similar to the sensor element 3, it includes a vibrator that bends and vibrates, and detects the angular velocity using the Coriolis force.

[0063] The sensor element 3b is an acceleration sensor that detects the acceleration in the X-axis direction. The sensor element 3b includes a crystal oscillator, and detects the acceleration using the change in the oscillation frequency of the crystal oscillator. The sensor element 3b may be configured to include a silicon MEMS having comb-shaped fixed electrodes and movable electrodes, and detect the acceleration using the change in the capacitance formed therebetween.

[0064] In FIG. 8B, the sensor device 12b includes an angular velocity sensor that detects the angular velocity around the X-axis and an acceleration sensor that detects the acceleration in the X-axis direction, but the sensor device 12b is not limited to this configuration. For example, in addition to the sensor elements 3a and 3b, the sensor device 12b may include an angular velocity sensor element that detects the angular velocity around the Z axis and / or an angular velocity sensor element that detects the angular velocity around the Y axis. For example, in addition to the sensor elements 3a and 3b, the sensor device 12b may include an acceleration sensor element that detects the acceleration in the Z-axis direction and / or an acceleration sensor element that detects the acceleration in the Y-axis direction. For example, the sensor element 3a may be a three-axis angular velocity sensor that detects the angular velocity around each of the X, Y, and Z axes. For example, the sensor element 3b may be a three-axis acceleration sensor that detects the acceleration in each of the X, Y, and Z axis directions. For example, the sensor element 3b may be an angular velocity sensor that detects the angular velocity around the Z axis and / or the Y axis, or a three-axis angular velocity sensor that detects the angular velocity around each of the X, Y, and Z axes. For example, the sensor element 3a may be a three-axis angular velocity sensor that detects the angular velocity around each of the X, Y, and Z axes, and the sensor element 3b may be a three-axis acceleration sensor that detects the acceleration in each of the X, Y, and Z axis directions. In other words, the sensor device 12b may be a three-axis angular velocity sensor, a three-axis acceleration sensor, or a 6DoF (Six degrees of freedom) sensor.

[0065] When a ceramic package is used for the package 7, the package 7 can be regarded as a rigid substrate. In this case, the sensor elements 3, 3a, and 3b can be regarded as the sensor device 12b. When a ceramic package is used for the package 7, the package 7 may be configured to be directly mounted on a flexible substrate.

[0066] 1.7. Regarding the sensor element and the circuit element 1.7.1. Configuration FIG. 9 shows a detailed configuration example of the sensor element 3 and the circuit element 4 of the sensor device 12b shown in FIG. 8A. The sensor devices 11a, 12a, 13a, 11b, and 13b also have a similar configuration.

[0067] The sensor device 12b includes a sensor element 3 and a circuit element 4. The sensor element 3 includes a vibrator 1, and the circuit element 4 includes a drive circuit 81 and a detection circuit 82.

[0068] The drive circuit 81 can include an amplifier circuit that inputs a feedback signal DG from the vibrator 1 and performs signal amplification, an AGC (Automatic Gain Control) circuit that performs automatic gain control, an output circuit that outputs a drive signal DS to the vibrator 1, and the like. The AGC circuit automatically adjusts the gain variably so that the amplitude of the feedback signal DG from the vibrator 1 becomes constant. The output circuit outputs, for example, a rectangular-wave drive signal DS to the vibrator 1.

[0069] The detection circuit 82 can include an amplifier circuit, a synchronous detection circuit, an A / D conversion circuit, etc. The amplifier circuit inputs detection signals S1, S2 from the vibrator 1 and performs charge-voltage conversion and signal amplification of the differential detection signals S1, S2. The synchronous detection circuit performs synchronous detection for extracting a desired wave using a synchronous signal from the drive circuit 81. The A / D conversion circuit converts the analog detection signals S1, S2 after synchronous detection into digital detection data D1 and outputs it to the arithmetic circuit 14.

[0070] The arithmetic circuit 14 performs various processes such as temperature correction, zero-point correction, sensitivity adjustment, and filter processing on the detection data D1, and outputs the processed detection data D2 to the outside via the connector 15.

[0071] In the present embodiment, the vibrator 1 is a vibrator having a double-T structure. As the vibrator 1, a tuning fork type or H type vibrator may be used. The vibrator 1 has drive arms 98a, 98b, 98c, 98d, detection arms 99a, 99b, a base 91, and connecting arms 92a, 92b.

[0072] The base 91 has a rectangular shape, and a detection arm 99a, a detection arm 99b, a connection arm 92a, and a connection arm 92b are provided on each side of the base 91. A drive arm 98a and a drive arm 98b are provided at the tip of the connection arm 92a. A drive arm 98c and a drive arm 98d are provided at the tip of the connection arm 92b.

[0073] At the tips of the drive arms 98a, 98b, 98c, 98d and the detection arms 99a, 99b, weight portions for frequency adjustment are provided. Assuming that the X-axis direction is the thickness direction of the vibrator 1, the vibrator 1 detects the angular velocity around the X-axis.

[0074] Drive electrodes 93 are formed on the plus side surface and the minus side surface of the drive arms 98a, 98b in the X-axis direction. Drive electrodes 94 are formed on the plus side surface and the minus side surface of the drive arms 98a, 98b in the Y-axis direction. Drive electrodes 94 are formed on the plus side surface and the minus side surface of the drive arms 98c, 98d in the X-axis direction. Drive electrodes 93 are formed on the plus side surface and the minus side surface of the drive arms 98c, 98d in the Y-axis direction.

[0075] The drive electrodes 93, 94 are electrically connected to the drive circuit 81. The drive circuit 81 supplies a drive signal DS to the drive electrode 93 and a feedback signal DG is input from the drive electrode 94.

[0076] Detection electrodes 95 are formed on the plus side surface and the minus side surface of the detection arm 99a in the X-axis direction. Ground electrodes 97 are formed on the plus side surface and the minus side surface of the detection arm 99a in the Y-axis direction. Detection electrodes 96 are formed on the plus side surface and the minus side surface of the detection arm 99b in the X-axis direction. Ground electrodes 97 are formed on the plus side surface and the minus side surface of the detection arm 99b in the Y-axis direction. The detection electrodes 95 and 96 are electrically connected to the detection circuit 82. The detection circuit 82 receives detection signals S1 and S2 from the detection electrodes 95 and 96.

[0077] 1.7.2. Operation The sensor element 3 and the circuit element 4 operate as follows. When a drive signal DS is applied from the drive circuit 81 to the drive electrode 93, the drive arms 98a, 98b, 98c, and 98d perform bending vibrations as indicated by the arrow C1 due to the inverse piezoelectric effect. Specifically, the tips of the drive arm 98a and the drive arm 98c approach and separate from each other repeatedly, and the tips of the drive arm 98b and the drive arm 98d also approach and separate from each other repeatedly.

[0078] In other words, the drive arms 98a, 98b, 98c, and 98d repeat the vibration postures indicated by the solid arrow C1 and the dotted arrow C1 at a predetermined frequency. The predetermined frequency is, for example, 51.0 kHz.

[0079] In the present embodiment, the frequency of the bending vibration of the drive arms 98a, 98b, 98c, and 98d is an example of the drive frequency of the sensor device 12b. The frequency of the bending vibration of the drive arms 98a, 98b, 98c, and 98d may be defined by the frequency of the drive signal DS. This is because the frequency of the drive signal DS has a correlation with the frequency of the bending vibration of the drive arms 98a, 98b, 98c, and 98d. Similarly, the drive frequency of the sensor device 12b may be defined by a signal having a correlation with the frequency of the bending vibration of the drive arms 98a, 98b, 98c, and 98d.

[0080] The bending vibrations of the drive arm 98a and the drive arm 98b and the bending vibrations of the drive arm 98c and the drive arm 98d are vibrations that are line-symmetric with respect to the X axis passing through the center-of-gravity position of the base 91. Therefore, due to the bending vibrations of the drive arms 98a, 98b, 98c, and 98d, the base 91, the connecting arm 92a, the connecting arm 92b, the detection arm 99a, and the detection arm 99b hardly vibrate.

[0081] In this state, when an angular velocity with the X-axis as the rotation axis is applied to the vibrator 1, the drive arms 98a, 98b, 98c, and 98d vibrate as shown by the arrow C2 due to the Coriolis force. In other words, the Coriolis force in the direction of the arrow C2, which is orthogonal to the direction of the arrow C1 and the direction of the X-axis, acts on the drive arms 98a, 98b, 98c, and 98d, thereby generating a vibration component in the direction of the arrow C2.

[0082] This vibration in the direction of the arrow C2 is transmitted to the base 91 via the connecting arms 92a and the connecting arm 92b, whereby the detection arms 99a and the detection arm 99b bend and vibrate in the direction of the arrow C3. Charge signals generated by the piezoelectric effect due to the bending vibration of the detection arms 99a and 99b are input into the detection circuit 82 as detection signals S1 and S2, and the angular velocity around the X-axis is detected.

[0083] 1.8. Variation 1.8.1. Variation 1 FIG. 10 is a perspective view of a sensor device 12c according to a variation of the sensor devices 12a, 12b, 13a, and 13b, and the sensor devices 12a, 12b, 13a, and 13b can be replaced with the sensor device 12c.

[0084] As shown in FIG. 10, the sensor device 12c includes a vibrator 1 disposed therein in the vertical direction. The vertical direction means that the vibrator 1 is disposed so as to be orthogonal to the X-axis direction which is the detection axis. In this way, the package form in which the vibrator 1 is vertically disposed with respect to the main surface f2 which is the mounting surface of the sensor device 12c is called a vertical package. A plurality of mounting terminals 29 are provided on the mounting surface 28 of the sensor device 12c.

[0085] 1.8.2. Variation 2 FIG. 11 is a developed view according to a variation of the substrate unit 20. In Modification 2, the substrate 21a has a main surface fa1 orthogonal to the Z-axis, a side surface fa2 orthogonal to the X-axis, and a side surface fa3 orthogonal to the Y-axis. The sensor device 11a is provided on the main surface fa1 of the substrate 21a, the sensor device 12a is provided on the side surface fa2 of the substrate 21a, and the sensor device 13a is provided on the side surface fa3 of the substrate 21a.

[0086] The substrate 22b has a main surface fb1 orthogonal to the Z-axis, a side surface fb2 orthogonal to the X-axis, and a side surface fb3 orthogonal to the Y-axis. The sensor device 11b is provided on the main surface fb1 of the substrate 22b, the sensor device 12b is provided on the main surface fb2 of the substrate 22b, and the sensor device 13b is provided on the side surface fb3 of the substrate 22b.

[0087] In Modification 2, the substrate 21a is an example of a first substrate, the main surface fa1 is an example of a first surface, the side surface fa2 is an example of a second surface, and the side surface fa3 is an example of a third surface. The substrate 22b is an example of a second substrate, the main surface fb1 is an example of a fourth surface, the side surface fb2 is an example of a fifth surface, and the side surface fb3 is an example of a sixth surface.

[0088] In the above-described embodiment, an example in which the number of sensor devices on each of the X, Y, and Z axes is the same has been described, but the number of sensor devices may be different for each axis. For example, the number of sensor devices on the X-axis may be 1, the number of sensor devices on the Y-axis may be 1, and the number of sensor devices on the Z-axis may be 2.

[0089] As described above, the sensor module 100 of the present embodiment has the following effects. The sensor module 100 of this embodiment includes a substrate 21 as a first substrate, a substrate 22 as a second substrate, and a flexible substrate 40 as a connection part connecting between the substrate 21 and the substrate 22. The substrate 21 has a sensor device 11a as a first sensor device for detecting an angular velocity around the Z-axis as a physical quantity of the first axis, a sensor device 12a as a second sensor device for detecting an angular velocity around the X-axis as a physical quantity of the second axis, and a sensor device 13a as a third sensor device for detecting an angular velocity around the Y-axis as a physical quantity of the third axis. The substrate 22 has a sensor device 11b as a fourth sensor device for detecting an angular velocity around the Z-axis, a sensor device 12b as a fifth sensor device for detecting an angular velocity around the X-axis, and a sensor device 13b as a sixth sensor device for detecting an angular velocity around the Y-axis.

[0090] Thus, the sensor module 100 of this embodiment includes two each of the first sensor device which is a Z-axis angular velocity sensor, the second sensor device which is an X-axis angular velocity sensor, and the third sensor device which is a Y-axis angular velocity sensor. The two angular velocity sensors of the same axis are provided separately on the substrate 21 and the substrate 22. Therefore, interference between the angular velocity sensors of the same axis is suppressed, and the effectiveness of improving the accuracy of the angular velocity data of each axis can be enhanced.

[0091] In the sensor module 100 of this embodiment, the drive frequencies of the sensor device 11a and the sensor device 11b are each a first drive frequency, the drive frequencies of the sensor device 12a and the sensor device 12b are each a second drive frequency, and the drive frequencies of the sensor device 13a and the sensor device 13b are each a third drive frequency.

[0092] Thus, the driving frequencies of the three angular velocity sensors provided on the substrate 21 are different from each other. Similarly, the driving frequencies of the three angular velocity sensors provided on the substrate 22 are different from each other. Therefore, interference between the angular velocity sensors provided on the substrate 21 is suppressed, and similarly, interference between the angular velocity sensors provided on the substrate 22 is suppressed, so that the effectiveness of improving the accuracy of the angular velocity data for each axis can be enhanced.

[0093] In the sensor module 100 of the present embodiment, the substrate 21 has an arithmetic circuit 14 as a processing unit that receives the angular velocity about the Z-axis, the angular velocity about the X-axis, or the angular velocity about the Y-axis detected by the sensor devices 11a, 12a, 13a, 11b, 12b, and 13b, and performs a process of obtaining the average value of the angular velocities about each axis as a desired process and outputs the result.

[0094] Thus, in the sensor module 100 of the present embodiment, averaging processing is performed based on the angular velocities with interference between the plurality of sensor devices 11a, 12a, 13a, 11b, 12b, and 13b suppressed, so that the effectiveness of improving the accuracy is ensured.

[0095] In the sensor module 100 of the present embodiment, the substrate 21 has a connector 15 for electrically connecting the sensor module 100 to the outside. Therefore, based on the configuration in which the effectiveness of improving the accuracy is ensured, the sensor module 100 of the present embodiment can output highly accurate and reliable detection data D2 to the outside via the connector 15.

[0096] In the sensor module 100 of this embodiment, the substrate 21 has a main surface f1 as a first surface orthogonal to the Z-axis, the substrate 22 has a main surface f2 as a second surface orthogonal to the Z-axis and facing the main surface f1, the sensor devices 11a, 12a, and 13a are respectively provided on the main surface f1, and the sensor devices 11b, 12b, and 13b are respectively provided on the main surface f2.

[0097] The sensor devices 11a, 12a, and 13a are all provided on the main surface f1 of the substrate 21, and the sensor devices 11b, 12b, and 13b are all provided on the main surface f2 of the substrate 22. Therefore, in the sensor module 100 of this embodiment, the mounting of the sensor devices 11a, 12a, and 13a on the substrate 21 and the mounting of the sensor devices 11b, 12b, and 13b on the substrate 22 can be easily performed. Thus, the sensor module 100 of this embodiment can realize a sensor module with excellent productivity and high industrial utility value.

[0098] In the sensor module 100 of this embodiment, the substrate 21 has a relay substrate 25a as a first relay substrate on which the sensor device 12a is mounted and a relay substrate 25b as a second relay substrate on which the sensor device 13a is mounted, and the substrate 22 has a relay substrate 25c as a third relay substrate on which the sensor device 12b is mounted and a relay substrate 25d as a fourth relay substrate on which the sensor device 13b is mounted.

[0099] Thus, since the sensor device 12a is provided on the substrate 21 in a state of being mounted on the relay substrate 25a, the mounting on the substrate 21 is easy and the productivity can be improved. The same applies to the sensor devices 13a, 12b, and 13b. Therefore, the sensor module 100 of this embodiment can realize a sensor module with excellent productivity and high industrial utility value.

[0100] In the sensor module 100 of the present embodiment, the substrate 21a as the first substrate has a main surface fa1 as a first surface orthogonal to the Z-axis as the first axis, a side surface fa2 as a second surface orthogonal to the X-axis as the second axis, and a side surface fa3 as a third surface orthogonal to the Y-axis as the third axis. The substrate 22b as the second substrate has a main surface fb1 as a fourth surface orthogonal to the Z-axis and facing the main surface fa1, a side surface fb2 as a fifth surface orthogonal to the X-axis, and a side surface fb3 as a sixth surface orthogonal to the Y-axis. The sensor device 11a is provided on the main surface fa1, the sensor device 12a is provided on the side surface fa2, the sensor device 13a is provided on the side surface fa3, the sensor device 11b is provided on the main surface fb1, the sensor device 12b is provided on the side surface fb2, and the sensor device 13b is provided on the side surface fb3.

[0101] Thus, since the sensor device 12a is provided on the side surface fa2 of the substrate 21, the protrusion from the main surface fa1 of the substrate 21 can be reduced. The same applies to the sensor devices 13a, 12b, and 13b. Therefore, according to this configuration, the thinning of the sensor module 100 can be easily realized.

[0102] The sensor module 100 of the present embodiment includes a fixing frame 60 as a fixing portion for fixing the substrate 21 and the substrate 22. The substrate 21 and the substrate 22 are respectively fixed to the fixing frame 60. Therefore, the sensor module 100 of the present embodiment can easily and surely fix the substrate 21 and the substrate 22. Thus, the sensor module 100 of the present embodiment can improve the effectiveness and reliability of the high-precision detection data D1 and D2.

[0103] The sensor module 100 of the present embodiment includes an inner case 30 and / or an outer case 50 as a case for housing the substrate 21 and the substrate 22. Thus, since the sensor module 100 of the present embodiment is housed in the inner case 30 and / or the outer case 50, it is possible to block the influence from the outside, and it is possible to improve the effectiveness and reliability of the detection data D1 and D2 with high precision.

[0104] 2. Embodiment 2 In Embodiment 2, an electronic device including the sensor module 100 will be described. Hereinafter, as examples of the electronic device, an example of a portable device such as a smartphone and an example of a moving body such as an automobile will be described.

[0105] 2.1. Outline of Portable Device FIG. 12 is a perspective view of a portable device as an electronic device according to Embodiment 2, and is a diagram showing the configuration of a smartphone 110 as an example of the portable device.

[0106] The smartphone 110 is equipped with the sensor module 100. The detection data D2 of the sensor module 100 is received by the control unit 111. The control unit 111 recognizes the posture and behavior of the smartphone 110 from the received signal, and can change the display image displayed on the display unit, sound a warning sound or an effect sound, or drive a vibration motor to vibrate the main body.

[0107] The sensor module 100 may be mounted on other portable devices other than the smartphone 110. For example, the sensor module 100 may be mounted on portable devices such as smartwatches, portable activity meters, HMDs (Head Mounted Displays), mobile PCs (Personal Computers), tablet PCs, cameras, and PDAs (Personal Digital Assistants). As a result, the portable device can recognize the posture and behavior of the portable device based on the detection data D2 of the sensor module 100, change the display image, sound a warning sound or an effect sound, drive a vibration motor to vibrate the main body, and so on.

[0108] Thus, in this embodiment, a mobile device such as the smartphone 110 is equipped with the sensor module 100. Therefore, according to this embodiment, the reliability of the mobile device equipped with the sensor module 100 can be improved.

[0109] 2.2. Overview of the Moving Object FIG. 13 is a perspective view of a moving object as an electronic device according to Embodiment 2, and is a diagram showing the configuration of an automobile 130 as an example of the moving object.

[0110] The automobile 130 is equipped with the sensor module 100. The sensor module 100 detects the attitude of the vehicle body 131 and transmits the detection data D2 to the vehicle body attitude control device 132. In this embodiment, the detection data D2 includes an angular velocity signal and an acceleration signal. When the vehicle body attitude control device 132 that controls the attitude of the vehicle body 131 receives the detection data D2 of the sensor module 100, it detects the attitude of the vehicle body 131 based on the signal, and controls the hardness and softness of the suspension or controls the brakes of the individual wheels 133 according to the detection result.

[0111] The detection data D2 of the sensor module 100 may also be utilized in other ECUs (Electronic Control Units) such as keyless entry, immobilizer, car navigation system, car air conditioner, antilock brake system (ABS), airbag, TPMS (Tire Pressure Monitoring System), engine control, control devices for inertial navigation for autonomous driving, and battery monitors for hybrid vehicles and electric vehicles.

[0112] The sensor module 100 may be mounted on other moving objects other than the automobile 130. Other moving objects are, for example, bipedal robots, trains, radio-controlled airplanes, radio-controlled helicopters, drones, agricultural machinery, and construction machinery. The moving object equipped with the sensor module 100 can utilize the detection data D2 of the sensor module 100 for attitude control and position measurement of the moving object.

[0113] Thus, in this embodiment, a moving body such as the vehicle 130 is equipped with the sensor module 100. Therefore, according to this embodiment, the reliability of the moving body equipped with the sensor module 100 can be improved.

[0114] As described above, the preferred embodiments have been described, but the present invention is not limited to the above-described embodiments. The configuration of each part of the present invention can be replaced with any configuration that exhibits the same functions as those of the above-described embodiments, and any configuration can be added.

Explanation of Reference Numerals

[0115] 1…Vibrator, 2…Support substrate, 3, 3a, 3b…Sensor element, 4…Circuit element, 5…Base, 6…Lid, 7…Package, 8a, 8b…Internal terminal, 8c…External terminal, 9…Bonding wire, 10…Sensor unit, 11a, 11b, 12a, 12b, 12c, 13a, 13b…Sensor device, 14…Arithmetic circuit, 15…Connector, 16…Memory, 17…Power supply circuit, 18…Temperature sensor, 20…Substrate unit, 21, 21a, 22, 22b…Substrate, 25a, 25b, 25c, 25d…Relay substrate, 27…Pin header, 28…Mounting surface, 29…Mounting terminal, 30…Inner case, 31…Opening, 32…Side wall, 33…Recess, 34…Upper surface, 40…Flexible substrate, 50…Outer case, 52…Screw hole, 53…Inner side, 54…Side wall, 55…Bottom surface, 57…Upper surface, 58…Lower surface, 60…Fixing frame, 61…Upper surface, 62…Lower surface, 68…Opening, 70…Screw, 71…Mounted surface, 81…Drive circuit, 82…Detection circuit, 91…Base portion, 92a, 92b…Linking arm, 93, 94…Drive electrode, 95, 96…Detection electrode, 97…Ground electrode, 98a, 98b, 98c, 98d…Drive arm, 99a, 99b…Detection arm, 100…Sensor module, 110…Smartphone, 111…Control unit, 130…Automobile, 131…Vehicle body, 132…Vehicle body attitude control device, 133…Wheel, C1, C2, C3…Arrow, D1, D2…Detection data, S1, S2…Detection signal, DS…Drive signal, DG…Feedback signal, f1, fa1, fb1…Main surface, fu1…Upper surface, f2…Main surface, fd2…Lower surface, fa2, fb2…Side surface, fa3, fb3…Side surface.

Claims

1. A sensor module comprising a first substrate, a second substrate, and a connection portion connecting between the first substrate and the second substrate, wherein the first substrate has a first sensor device for detecting a physical quantity of a first axis, a second sensor device for detecting a physical quantity of a second axis, and a third sensor device for detecting a physical quantity of a third axis, and the second substrate has a fourth sensor device for detecting a physical quantity of the first axis, a fifth sensor device for detecting a physical quantity of the second axis, and a sixth sensor device for detecting a physical quantity of the third axis.

2. The driving frequency of the first sensor device and the driving frequency of the fourth sensor device are each a first driving frequency, the driving frequency of the second sensor device and the driving frequency of the fifth sensor device are each a second driving frequency, and the driving frequency of the third sensor device and the driving frequency of the sixth sensor device are each a third driving frequency. The sensor module according to Claim 1.

3. The first substrate has a processing portion into which the physical quantity of the first axis, the physical quantity of the second axis, or the physical quantity of the third axis detected by the first sensor device, the second sensor device, the third sensor device, the fourth sensor device, the fifth sensor device, and the sixth sensor device is input, and which performs a desired process and outputs the result. The sensor module according to Claim 1.

4. The first substrate has a connector for electrically connecting the sensor module to the outside. The sensor module according to Claim 1.

5. The first substrate has a first surface orthogonal to the first axis, the second substrate has a second surface orthogonal to the first axis and facing the first surface, the first sensor device, the second sensor device, and the third sensor device are each provided on the first surface, and the fourth sensor device, the fifth sensor device, and the sixth sensor device are each provided on the second surface. The sensor module according to Claim 1.

6. The first substrate has a first relay substrate on which the second sensor device is mounted and a second relay substrate on which the third sensor device is mounted. ​ The second substrate includes a third relay substrate on which the fifth sensor device is mounted, and a fourth relay substrate on which the sixth sensor device is mounted. The sensor module according to claim 1.

7. The first substrate has a first surface orthogonal to the first axis, a second surface orthogonal to the second axis, and a third surface orthogonal to the third axis. The second substrate has a fourth surface orthogonal to the first axis and facing the first surface, a fifth surface orthogonal to the second axis, and a sixth surface orthogonal to the third axis. The first sensor device is provided on the first surface. The second sensor device is provided on the second surface. The third sensor device is provided on the third surface. The fourth sensor device is provided on the fourth surface. The fifth sensor device is provided on the fifth surface. The sixth sensor device is provided on the sixth surface. The sensor module according to claim 1.

8. The sensor module includes a fixing portion that fixes the first substrate and the second substrate. The sensor module according to claim 1.

9. The sensor module includes a case that houses the first substrate and the second substrate. The sensor module according to claim 1.

10. An electronic device including the sensor module according to any one of claims 1 to 9.

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