阅读说明：本技术 传感器单元、电子设备以及移动体 (Sensor unit, electronic apparatus, and moving object ) 是由 木下裕介 佐久间正泰 于 2015-07-13 设计创作，主要内容包括：本发明提供一种传感器单元、电子设备以及移动体,所述传感器单元可靠性较高、且即使针对被安装物的振动而检测精度也较为稳定。传感器单元(100)的特征在于,具备：传感器模块(25),其被构成为包括安装有惯性传感器(17x、17y、17z、18)的基板(15)、和搭载有基板(15)的内壳(20)；外壳(1),其对传感器模块(25)进行收纳,在内壳(20)上形成有凹部(31),在从基板(15)的厚度方向进行观察的俯视观察时,在与凹部(31)重叠的区域内配置有惯性传感器(17x、17y、17z、18),且在由基板(15)以及凹部(31)所形成的空间内填充有填充部件(50),并且传感器模块(25)经由接合部件(10)而与外壳(1)的底壁(5)接合。(The invention provides a sensor unit, an electronic apparatus, and a moving object, wherein the sensor unit has high reliability and stable detection precision even for vibration of an object to be mounted. A sensor unit (100) is characterized by being provided with: a sensor module (25) configured to include a substrate (15) on which inertial sensors (17x, 17y, 17z, 18) are mounted, and an inner case (20) on which the substrate (15) is mounted; an outer case (1) that houses the sensor module (25), wherein a recess (31) is formed in the inner case (20), wherein inertial sensors (17x, 17y, 17z, 18) are arranged in a region that overlaps with the recess (31) when viewed in a plan view when viewed from the thickness direction of the substrate (15), wherein a space formed by the substrate (15) and the recess (31) is filled with a filler member (50), and wherein the sensor module (25) is joined to the bottom wall (5) of the outer case (1) via a joining member (10).)

1. A sensor unit, when three axes orthogonal to each other are set as an X-axis, a Y-axis, and a Z-axis, the sensor unit includes:

a substrate including a surface and a back surface in a front-to-back relationship with each other orthogonal to the Z axis, a first side surface orthogonal to the X axis, and a second side surface orthogonal to the Y axis;

a first gyro sensor mounted on the first side surface of the substrate and detecting an angular velocity in the X-axis direction;

a second gyro sensor mounted on the second side surface of the substrate and detecting an angular velocity in the Y-axis direction;

a third gyro sensor mounted on the surface of the substrate and detecting an angular velocity in the Z-axis direction;

an acceleration sensor mounted on the surface of the substrate and detecting accelerations in the X-axis direction, the Y-axis direction, and the Z-axis direction;

a connector including an external connection terminal and an input/output terminal in a front-back relationship with each other, the external connection terminal being mounted on the surface of the substrate;

an inner case that includes an exposed surface orthogonal to the Z axis and on which the substrate is mounted so as to face the front surface side of the substrate;

a housing provided with a first opening portion that opens in the Z-axis direction and including a bottom wall orthogonal to the Z-axis and a side wall that contacts the bottom wall,

the inner case is housed in a space surrounded by the first opening, the bottom wall, and the side wall of the outer case, and is mounted on the bottom wall of the outer case via an elastic member,

the exposed surface of the inner case is exposed from the first opening,

the input/output terminal of the connector faces the Z-axis direction.

2. The sensor unit of claim 1,

a control IC that controls the first gyro sensor, the second gyro sensor, the third gyro sensor, and the acceleration sensor is mounted on the back surface of the substrate.

3. The sensor unit of claim 1,

the inner case is provided with a second opening portion that opens in the Z-axis direction,

the input/output terminal of the connector is exposed from the second opening.

4. The sensor unit of claim 1,

the elastic modulus of the elastic member is small compared to the elastic modulus of the housing.

5. The sensor unit of claim 1,

a first bonding surface having a smaller distance from the first opening than a central portion is provided on a peripheral edge portion of the bottom wall,

the elastic member is disposed on the first bonding surface.

6. The sensor unit of claim 1,

the elastic member is in contact with the side wall of the housing.

7. The sensor unit of claim 1,

the inner case is provided with a recess on the side of the substrate,

the first gyro sensor, the second gyro sensor, the third gyro sensor, and the acceleration sensor are disposed in a space surrounded by the substrate and the concave portion.

8. The sensor unit of claim 7,

the space is filled with a filling member,

the first gyro sensor, the second gyro sensor, the third gyro sensor, and the acceleration sensor are covered with the filler member.

9. The sensor unit of claim 7 or 8,

the surface of the substrate is provided with a groove or a through-hole opening to the recess in a region overlapping the recess when viewed in a plan view in the Z-axis direction.

10. An electronic device, wherein,

a sensor unit according to any one of claims 1 to 9.

11. A moving body in which, in a moving body,

a sensor unit according to any one of claims 1 to 9.

Technical Field

The present invention relates to a sensor unit, an electronic apparatus including the sensor unit, and a moving object.

Background

Conventionally, as a sensor unit on which an inertial sensor for detecting inertia based on a predetermined detection axis is mounted, there is known a sensor unit (device) 91 having a structure in which an angular velocity sensor 83 is mounted inside a box-shaped housing 80 as shown in fig. 27. Specifically, a structure is adopted in which a substrate 82 on which an angular velocity sensor 83 is mounted is directly fixed to a bottom surface 81 inside a box-shaped case 80. The angular velocity sensor 83 is formed by MEMS (Micro Electro Mechanical Systems) technology on a semiconductor substrate as a comb actuator 84 having a weight or comb-shaped electrode, and electrically (for example, as a capacitance change) reads a change caused by a coriolis force acting when an angular velocity is applied.

On the other hand, in the conventional structure as described above, there is a problem that the structure is easily affected by the inherent vibration (noise vibration) transmitted from the mounted surface 85 (device), and the influence on the detection accuracy cannot be denied. For example, when the sensor unit 91 is mounted on a navigation system, noise vibration caused by the operation of the engine of the automobile may be directly transmitted from the bottom surface 81 of the housing 80 to the angular velocity sensor 83. This is not limited to the package structure of the angular velocity sensor, but is a common problem in the package structure of the entire inertial sensor such as an acceleration sensor.

In view of the above, patent document 1 proposes a sensor device as shown in fig. 28 to 30. In the sensor device 92 of fig. 28, the substrate 82 including the angular velocity sensor 83 is suspended from the bottom surface 81 of the housing 80 by the metal spring 86 in a state where the housing 80 is inverted (vertically inverted). In the sensor device 93 of fig. 29, the substrate 82 including the angular velocity sensor 83 is suspended from the outer peripheral edge of the housing 80 by the flexible substrate 87. In the sensor device 94 of fig. 30, a stepped level difference 88 is formed in the peripheral edge portion inside the case 80, and a plurality of bonding wires 89 are led out from the level difference 88, and the substrate 82 including the angular velocity sensor 83 is suspended. According to this document, the influence of noise vibration can be sufficiently attenuated by the structure of the sensor devices 92 to 94.

Prior art documents

Patent document

Patent document 1: japanese laid-open patent publication No. 2006 + 194681

Disclosure of Invention

Problems to be solved by the invention

However, the sensor devices 92 to 94 of patent document 1 have problems that reliability is poor and it is difficult to obtain stable detection accuracy. Specifically, in any of the sensor devices 92 to 94, the position of the substrate 82 including the angular velocity sensor 83 is in a floating state inside the housing 80, and therefore the angular velocity sensor 83 is inclined due to its own weight or a change over time. When the angular velocity sensor 83 is tilted, the comb actuator 84 is biased by the influence of gravity, and therefore the detection result is affected, and reliability is low.

In the case of the structure in which the substrate 82 is suspended by the springs 86, the substrate 82 may vibrate vertically due to the influence of noise vibration. The vertical vibration may also affect the detection result, and it is difficult to obtain stable detection accuracy. Further, since the sensor devices 93 and 94 are configured such that the substrate 82 is suspended by a member having elasticity, vibration of the substrate 82 due to the influence of noise vibration is also generated, and it is difficult to obtain stable detection accuracy in the same manner.

Means for solving the problems

The present invention is an invention for solving at least part of the above problems, and can be realized as the following application examples and embodiments.

(application example)

The sensor unit is characterized by comprising: an inertial sensor; a sensor module on which the inertial sensor is mounted; and a housing that has a bottom wall and a side wall that contacts the bottom wall, and that houses the sensor module, wherein the sensor module is joined to the bottom wall of the housing via a joining member.

According to this structure, the sensor module is joined to the bottom wall of the housing via the joining member. Preferably, the sensor module is fitted in the housing, and an annular joining member is disposed along the fitting portion to join the sensor module and the housing. The joining member may have adhesiveness, and the two may be joined in a state where the joining member is compressed.

Further, since the housing, the joint member, and the sensor module (the housing portion) can be formed with high accuracy by cutting or molding, and these portions are assembled in a stacked manner in this order, unlike the conventional configuration in which the inertial sensor is suspended, the sensor module on which the inertial sensor is mounted can be positioned with high accuracy.

Therefore, according to the sensor unit of the application example, the position of the inertial sensor is stabilized, so that the reliability is improved, and the sensor unit is provided with the joint member having vibration-proof property, so that the sensor unit is less susceptible to noise vibration, and the detection accuracy is stabilized. Therefore, the sensor unit having high reliability and stable detection accuracy can be provided.

Preferably, the joining member is made of a material having a smaller elastic modulus than the housing. As described above, it is preferable that the both are bonded by the annular bonding member, and therefore, airtightness can be ensured. In this way, since the joint member also functions as the vibration isolation member by using a material having a smaller elastic modulus than the housing as the joint member, transmission of noise vibration from the housing to the sensor module can be suppressed.

This makes it less susceptible to the external environment, and can further improve reliability.

Preferably, the housing has a box shape in which a surface facing the bottom wall is an opening surface, and the sensor module is housed so as to close the opening of the opening surface, the bottom wall has a first bonding surface formed on a peripheral edge portion thereof at a distance from the opening surface smaller than that of the central portion, and the bonding member is disposed so as to contact the first bonding surface.

Preferably, the height of the exposed surface of the sensor module from the outer surface of the bottom wall is lower than the height of the opening surface of the housing from the outer surface of the bottom wall.

According to this configuration, when the sensor unit is mounted on the mounting surface of the external device or the like, only the upper surface of the housing is in contact with the mounting surface, and therefore, the noise vibration propagating from the external device side to the sensor unit can be suppressed by the joining member.

Further, it is preferable that the housing and the sensor module are joined together by a joining member inserted from a through hole provided on the bottom wall.

According to this structure, the housing and the sensor module can be firmly fixed by the coupling member. Here, since the joining member is disposed between the housing and the sensor module, in the coupling structure of the housing and the sensor module by the coupling member, it is possible to achieve an effect of suppressing propagation of noise vibration from the housing to the sensor module and improving airtightness.

Further, it is also preferable that the engaging member is released from the side wall (or the bottom wall, or the first engaging surface which is a part of the bottom wall) of the housing and also comes into contact with the side wall.

Preferably, the sensor module includes: an inertial sensor; a substrate on which an inertial sensor is mounted; and an inner case on which the substrate is mounted, wherein a second bonding surface that overlaps the bonding member is formed on a peripheral edge portion of the inner case on a side facing the bottom wall.

According to this structure, since the inner case is fitted into the outer case in a box-like manner, a compact and robust package structure can be realized. Further, since the outer case, the engagement member, and the inner case (sensor module) are overlapped, the assembly is easy and the manufacturing efficiency is high.

Further, it is preferable that the base plate is bonded to the inner case by an adhesive having elasticity in a cured state. According to this configuration, since the vibration isolating member has a two-stage structure, the influence of noise vibration can be further reduced, and the reliability can be further improved.

Preferably, a connector for connection to the outside is mounted on the substrate, and the inner case has an opening formed therein so that the connector is exposed to the outside from the opening surface of the outer case.

Preferably, the inner case has a recess, the inertial sensor is disposed in a region overlapping the recess in a plan view seen in a thickness direction of the substrate, a space formed by the substrate and the recess is filled with a filler, and the sensor module is joined to the bottom wall of the outer case via a joining member.

According to this configuration, in the sensor module including the substrate on which the inertial sensor is mounted and the inner case, the space formed by the recess portions of the substrate and the inner case is filled with the filler member. Thus, the resonance frequency of the sensor module is shifted from the frequency band of the noise vibration from the outside, and the influence of the noise vibration can be reduced. In particular, in the sensor module, the inertial sensor is disposed in a region overlapping the recess in a plan view when viewed from the thickness direction of the substrate, and therefore the inertial sensor can be made less susceptible to external noise vibration.

Therefore, it is possible to provide a sensor unit which is less susceptible to noise vibration and has stable detection accuracy.

Further, it is preferable that at least a part of the body of the inertial sensor is disposed in the space of the sensor module.

In this application example, the body of the sensor module refers to both the sensor module main body and the outer shape of the sensor module in a state of being mounted on the substrate.

According to this configuration, since at least a part of the inertial sensor is covered with the filling member filled in the space formed by the substrate and the recess, it is possible to more effectively suppress the inertial sensor from being affected by noise vibration from the outside.

Further, the entire body or a large part of the body of the inertial sensor is disposed in the space formed by the substrate and the recess, and therefore, the inertial sensor is less likely to be affected by noise vibration, which is more preferable.

Further, the sensor unit is characterized in that a shelf portion higher than a concave bottom surface of the concave portion in a thickness direction of the inner case is formed on a part of a peripheral edge of the concave portion.

According to this configuration, in the case where the filling member filled in the space formed by the substrate of the sensor module and the recess of the inner case has a larger volume than the space in the assembly process of the sensor module, an excessive amount of the filling member is accommodated in the shelf portion provided at the peripheral edge portion of the recess. This can prevent an excessive amount of the filling member from overflowing to an undesired portion.

Therefore, it is possible to provide a sensor unit in which the filling amount of the filling member filled in the concave portion can be easily managed in the manufacturing process.

Preferably, in a planar view seen from a thickness direction of the substrate, a groove portion or a through hole portion opening to the recessed portion is formed in a region overlapping with the recessed portion.

According to this configuration, in the case where the volume of the filling member filled in the space formed by the substrate of the sensor module and the recess of the inner case is larger than the volume of the space in the assembly process of the sensor module, an excessive amount of the filling member is accommodated in the groove portion or the through-hole portion of the substrate. This makes it possible to fill the space formed by the substrate and the recess with the filler member while suppressing an excessive amount of the filler member from overflowing to an undesired portion.

Therefore, it is possible to provide a sensor unit in which the filling amount of the filling member into the recess in the manufacturing process can be easily managed, or the effect of suppressing the influence of noise vibration by the filling member can be more remarkably obtained.

Preferably, the joining member is any one of rubber, an elastic body, a porous member, and an adhesive. Preferably, the plurality of joining members are provided.

Preferably, the housing has a fixing portion for fixing to the body to be mounted. Further, preferably, the inertial sensor has a plurality of inertial sensors, and includes an acceleration sensor and an angular velocity sensor.

The sensor unit may be mounted on an electronic apparatus or a mobile body.

Drawings

Fig. 1 is a perspective view showing a state in which a sensor unit according to embodiment 1 is fixed to a mounting surface.

Fig. 2 is a perspective view showing an outline of the sensor unit as viewed from the mounted surface side of fig. 1.

Fig. 3 is an exploded perspective view of the sensor unit shown as viewed from the same direction as fig. 2.

Fig. 4 is a perspective view of the substrate.

Fig. 5 is a perspective view at section f-f of fig. 2.

Fig. 6 is an exploded perspective view of the sensor unit when viewed from the same direction as fig. 1.

Fig. 7 is a sectional view showing a vibration transmission suppressing structure in the sensor unit.

Fig. 8 is a plan view showing a substrate mounted on the sensor unit according to embodiment 2.

Fig. 9 is a cross-sectional view showing a vibration transmission suppressing structure in the sensor unit according to embodiment 2.

Fig. 10 is a cross-sectional view of an embodiment according to modified example 1.

Fig. 11 is a cross-sectional view of an embodiment according to modification 1.

Fig. 12 is a cross-sectional view of an embodiment according to modification 2.

Fig. 13 is a cross-sectional view of an embodiment according to modified example 2.

Fig. 14 is a perspective view of a sensor unit according to modified example 3.

Fig. 15 is an exploded perspective view of a sensor unit according to modification 4.

Fig. 16 is a sectional perspective view of a sensor unit according to modification 4.

Fig. 17 is a cross-sectional view showing an example of the sensor unit according to modified example 5.

Fig. 18 is a cross-sectional view showing an example of the sensor unit according to modified example 5.

Fig. 19 is a perspective view showing a state in which the sensor unit according to modified example 6 is fixed to a mounting surface.

Fig. 20 is a perspective view showing an outline of the sensor unit according to modified example 6 as viewed from the mounted surface side of fig. 19.

Fig. 21 is an exploded perspective view showing the sensor unit according to modified example 6 viewed from the same direction as 19.

Fig. 22 is a cross-sectional view showing a vibration transmission suppressing structure in the sensor unit according to modified example 6.

Fig. 23 is a cross-sectional view showing an example of the sensor unit according to modified example 7.

Fig. 24 is an external view showing an example of an electronic device.

Fig. 25 is an external view showing an example of an electronic device.

Fig. 26 is an external view showing an example of a moving body.

Fig. 27 is a sectional view showing a conventional package structure.

Fig. 28 is a cross-sectional view showing an example of a conventional package structure.

Fig. 29 is a cross-sectional view showing an example of a conventional package structure.

Fig. 30 is a cross-sectional view showing an example of a conventional package structure.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings described below, the layers or the members are illustrated in a scale different from the actual scale in order to make the layers or the members recognizable in the drawings.