Sensor device, and electronic apparatus

A sensor device includes a mounting member having fixation surfaces inside, and at least one electronic component directly or indirectly fixed to the fixation surfaces of the mounting member, and the mounting member constitutes a part of a casing for housing the electronic component. Further, the fixation surfaces are perpendicular to each other.

BACKGROUND

1. Technical Field

The present invention relates to a sensor device and an electronic apparatus.

2. Related Art

There is known such a sensor unit (sensor device) as disclosed in, for example, U.S. Pat. No. 7,040,922 (Document 1). The sensor unit described in Document 1 has a mounting member having a cuboid shape and three surfaces perpendicular to each other, and sensor devices mounted respectively on the three surfaces.

In the case of mounting such sensor devices on a circuit board or the like, it is difficult to mount the sensor devices directly on the circuit board, and the sensor devices are generally mounted in a condition of being housed in a casing composed of a pedestal and a lid member. However, if the sensor devices are housed in such a casing, there arises a problem of growth in size of the sensor devices. Further, if the sensor devices are fixed obliquely to the casing, there also arises a problem that the detection axes of the sensor devices are tilted to thereby degrade the detection accuracy. Therefore, the sensor devices downsizing of which can be achieved, and positioning of which is performed correctly have eagerly been desired.

SUMMARY

An advantage of the invention is to provide a sensor device and an electronic apparatus with which positioning of a sensor component can be performed with ease and accuracy while achieving downsizing.

An aspect of the invention is directed to a sensor device including a mounting member having a space formed inside, and a fixation surface exposed to the space, and a plurality of electronic components including a plurality of sensor components and fixed on the fixation surface side of the mounting member, the sensor components have respective detection axes intersecting with each other, and the mounting member constitutes a part of a casing housing the electronic components.

According to this configuration, it is possible to provide a sensor device with which positioning of a sensor component can be performed with ease and accuracy while achieving downsizing.

In the sensor device of the above aspect of the invention, it is preferable that the mounting member has a main body and a recessed section opened in an outer peripheral surface of the main body.

According to this configuration, the configuration of the mounting member becomes simple.

In the sensor device of the above aspect of the invention, it is preferable that the fixation surface includes at least a first fixation surface, a second fixation surface, and a third fixation surface intersecting with each other, and the sensor components are fixed respectively on the first fixation surface side, the second fixation surface side, and the third fixation surface side.

According to this configuration, the sensor device capable of detecting physical quantities around respective three axes intersecting with each other can be obtained.

In the sensor device of the above aspect of the invention, it is preferable that the casing has the mounting member, and a lid member mounted above the recessed section of the mounting member.

According to this configuration, infiltration of dust or the like into the casing can be prevented.

In the sensor device of the above aspect of the invention, it is preferable that the mounting member has a main body and a through hole penetrating the main body.

According to this configuration, the configuration of the mounting member becomes simple.

In the sensor device of the above aspect of the invention, it is preferable that the fixation surface includes a first fixation surface and a second fixation surface intersecting with each other.

According to this configuration, the detection axes of the sensor components can be made perpendicular to each other.

In the sensor device of the above aspect of the invention, it is preferable that the casing includes a first lid member adapted to cover one opening of the through hole, and a second lid member adapted to cover the other opening.

According to this configuration, infiltration of dust or the like into the casing can be prevented.

In the sensor device of the above aspect of the invention, it is preferable that an inner surface of the first lid member exposed to the through hole intersects with the first fixation surface and the second fixation surface.

According to this configuration, it is possible to fix the sensor component also to the inner surface, and the freedom of arrangement of the sensor components is enhanced.

In the sensor device of the above aspect of the invention, it is preferable that the fixation surface has a recessed section, and the sensor component is housed in the recessed section.

According to this configuration, it is possible to effectively use the space of the mounting member to thereby achieve the downsizing of the sensor device.

In the sensor device of the above aspect of the invention, it is preferable that the sensor components are mounted on a mounting board, the mounting board includes a plurality of boards on which the electronic components are mounted, and the plurality of boards are bendable between the boards.

According to this configuration, the fixation of the sensor components to the fixation surfaces becomes easy.

Another aspect of the invention is directed to an electronic apparatus including any of the sensor devices described above.

According to this configuration, an electronic apparatus capable of exerting excellent reliability can be obtained.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

Hereinafter, a sensor device and an electronic apparatus according to the invention will be explained in detail based on some exemplary embodiments shown in the accompanying drawings.

1. Sensor Device

First Embodiment

Firstly, a sensor device according to a first embodiment of the invention will be explained.

FIG. 1is a perspective view showing the sensor device according to the first embodiment of the invention,FIG. 2is a cross-sectional view of the sensor device shown inFIG. 1,FIGS. 3A and 3Bare development diagrams of a mounting board provided to the sensor device shown inFIG. 1, andFIG. 4is a plan view showing an example of an angular velocity sensor provided to the sensor device shown inFIG. 1. It should be noted that the explanation will hereinafter be presented defining the upper side ofFIG. 1as the “upper side” and the lower side thereof as the “lower side” for the sake of convenience of explanation. Further, as shown inFIG. 1, three axes perpendicular to each other are defined as an “x axis,” a “y axis,” and a “z axis,” respectively. The z axis is an axis parallel to the thickness direction of a pedestal4, the x axis is an axis parallel to the extending direction of a pair of sides of the pedestal opposed to each other, and the y axis is an axis parallel to the extending direction of the other pair of sides of the pedestal opposed to each other.

Further, hereinafter, the direction parallel to the x axis is defined as an “x-axis direction,” the direction parallel to the y axis is defined as a “y-axis direction,” and the direction parallel to the z axis is defined as a “z-axis direction.” Further, a plane including the x axis and the y axis is defined as an “x-y plane,” a plane including the y axis and the z axis is defined as a “y-z plane,” and a plane including the z axis and the x axis is defined as a “x-z plane.”

A sensor device1is a three-axis gyro sensor device provided with angular velocity sensors711,712, and713, and capable of detecting angular velocities around the x axis, the y axis, and the z axis perpendicular to each other, respectively. Such a sensor device1as described above is superior in convenience, and can preferably be used, for example, for motion trace, motion tracking, a motion controller, and pedestrian dead reckoning (PDR).

As shown inFIGS. 1 and 2, such a sensor device1as described above has a mounting board2on which electronic components7are mounted, and a casing10for housing the mounting board2. Hereinafter, each of these members will sequentially be explained.

The mounting board2is a rigid-flexible board obtained by combining rigid boards (substrates) hard and difficult to be deformed, and flexible boards soft, easy to be deformed, and provided with flexibility. The mounting board2is arranged to be able to be bent in portions between the rigid boards. As such a mounting board2as described above, there can be used a rigid-flexible board known to the public, for example, those having hard layers such as glass epoxy boards bonded to both sides of the flexible board, and using these parts as the rigid boards.

FIG. 3Ais a plan view of the mounting board2in a developed state viewed from one surface side, andFIG. 3Bis a plan view of the mounting board2in the developed state viewed from the other surface side. As shown inFIGS. 3A and 3B, the mounting board2is composed of a first rigid board21, a second rigid board22, a third rigid board23, a fourth rigid board24, and a fifth rigid board25disposed away from each other, and a flexible board26for connecting these rigid boards.

It should be noted that hereinafter surfaces of the rigid boards21through25shown inFIG. 3Aare referred to as “obverse-side mounting surfaces,” and surfaces shown inFIG. 3Bare referred to as “reverse-side mounting surfaces” for the sake of convenience of explanation.

The flexible board26has a first connection section261for connecting the first rigid board21and the third rigid board23, a second connection section262for connecting the second rigid board22and the third rigid board23, a third connection section263for connecting the third rigid board23and the fourth rigid board24, and a fourth connection section264for connecting the fourth rigid board24and the fifth rigid board25. Each of the connection sections261through264has flexibility, and therefore easily makes bending deformation in the surface direction.

The mounting board2is capable of changing the posture of the rigid boards21through25by bending the connection sections261through264of the flexible board26. Specifically, by bending the connection sections261through264so that obverse side mounting surfaces211through251of the respective rigid boards21through25face inward, the mounting board2can be deformed to have a cuboid shape in which the rigid boards adjacent to each other are perpendicular to each other. In this state, assuming that the third rigid board23forms a lower surface, the fourth rigid board24forms an upper surface, and the first, second, and fifth rigid boards21,22, and25respectively form side surfaces.

As described above, by constituting the mounting board2with the rigid-flexible board, it is possible to easily deform the mounting board2, and therefore, it becomes easy to fix the mounting board2to a mounting member3. Further, since the rigid boards21through25are connected to each other in a lump by the connection sections261through264, also in this regard, the fixation of the mounting board2to the mounting member3can be performed easily and smoothly. Further, since a plurality of rigid boards are provided, freedom of arrangement of the electronic components7increases.

Further, by mounting the electronic components7on the hard rigid board, unwanted vibration of the electronic components7(in particular the angular velocity sensors711through713, an acceleration sensor72) can be suppressed, and thus the detection accuracy of the sensor device1is improved. Further, the electronic components7are easy to be mounted on the mounting board2. Still further, the parallelism of the electronic components7can easily be achieved, and in particular, the angular velocity sensors711through713can easily be set to have desired postures, and the postures can be kept. Further, the electronic components7can also be mounted at high density.

Here, in the present embodiment, the third rigid board23has a cutout section23c, a cutout section23d, and a cutout section23eeach opened in an edge (an outer periphery) thereof. The cutout section23cis formed to have a step with respect to the upper side of the third rigid board23inFIG. 3A, and the first connection section261extends from the cutout section23c. Further, the cutout section23dis formed to have a step with respect to the left side of the third rigid board23inFIG. 3A, and the second connection section262extends from the cutout section23d. Further, the cutout section23eis formed to have a step with respect to the right side of the third rigid board23inFIG. 3A, and the third connection section263extends from the cutout section23e.

By providing the cutout section23cto the third rigid board23, it is possible to easily make the first connection section261have the bending deformation in the vicinity of (on the third rigid board23side of) a connection portion with the third rigid board23, and further, the curvature radius of the bending deformation can be kept relatively large. Further, excessive projection of the first connection section261is prevented, and thus downsizing of the sensor device1can be achieved. Substantially the same advantage can be achieved with respect to the cutout sections23d,23e.

Further, in the present embodiment, the fourth rigid board24has a cutout section24c, and a cutout section24deach opened in an edge (an outer periphery) thereof. The cutout section24cis formed to have a step with respect to the left side of the fourth rigid board24inFIG. 3A, and the third connection section263extends from the cutout section24c. Similarly, the cutout section24dis formed to have a step with respect to the lower side of the fourth rigid board24inFIG. 3A, and the fourth connection section264extends from the cutout section24d.

By providing the cutout section24cto the fourth rigid board24, it is possible to easily make the third connection section263have the bending deformation in the vicinity of (on the fourth rigid board24side of) a connection portion with the fourth rigid board24, and further, the curvature radius of the bending deformation can be kept relatively large. Further, excessive projection of a bent portion from the outer periphery of the fourth rigid board24is prevented, and thus downsizing of the sensor device1can be achieved. Substantially the same advantage can be achieved with respect to the cutout section24d.

The mounting board2is hereinabove explained. It should be noted that each of the rigid boards21through25, and the flexible board26of the mounting board2is provided with conductor patterns not shown, and the plurality of electronic components7are electrically connected in an appropriate manner via the conductor patterns.

Further, the mounting board2is provided with a ground layer not shown, and the ground layer exerts a function of blocking an external magnetic field. Therefore, in the condition of being fixed to the casing10, it is possible to eliminate the influence of the external magnetic field (external noise) from the outside of the sensor device1with respect to the electronic components7(i.e., the electronic components7mounted on the obverse side mounting surfaces211through251) located inside the mounting board2.

As shown inFIGS. 3A and 3B, on the mounting board2, there is mounted the plurality of electronic components7.

On the mounting board2, there are mounted as the electronic components7three angular velocity sensors (sensor components)711through713of a uniaxial detection type, the acceleration sensor (a sensor component)72of a triaxial detection type, a power supply circuit73for driving a variety of electronic components, an amplifier circuit74for amplifying output signals from the sensor components711through713, and72, an analog/digital converter circuit75for converting analog signals thus amplified by the amplifier circuit74into digital signals, a microcontroller76for performing desired control, a nonvolatile memory77such as an EEPROM, a direction sensor (a magnetic sensor)78for detecting the direction, and a connector (an interface connector)79for outputting signals. It should be noted that the electronic components7to be mounted thereon are not limited thereto, but it is possible to arbitrarily mount any components corresponding to the purpose.

Hereinafter, the arrangement of the electronic components7will be described in detail.

First Rigid Board21

On the obverse side mounting surface211of the first rigid board21, there is mounted the angular velocity sensor711.

Second Rigid Board22

On the obverse side mounting surface221of the second rigid board22, there is mounted the angular velocity sensor712.

Third Rigid Board23

On the obverse side mounting surface231of the third rigid board23, there are mounted the power supply circuit73, the amplifier circuit74, and the analog/digital converter circuit75, and on a reverse side mounting surface232, there are mounted the angular velocity sensor713and the acceleration sensor72.

The analog/digital converter circuit75is larger in size than the other electronic components7(the power supply circuit73and the amplifier circuit74) mounted on the obverse side mounting surface231. Therefore, it is preferable to dispose the analog/digital converter circuit75at a center portion of the obverse side mounting surface231. Thus, it is possible to effectively use the analog/digital converter circuit75as a reinforcement member for reinforcing the rigidity of the third rigid board23. Therefore, the unwanted vibration due to the flexural deformation of the third rigid board23can be suppressed, the unwanted vibration can be prevented from being transmitted to the angular velocity sensors711through713, and therefore the accuracy of the detection of the angular velocity by the angular velocity sensors711through713(in particular the angular velocity sensor713mounted on the third rigid board23) is improved.

Further, the angular velocity sensor713and the acceleration sensor72are preferably disposed in the vicinity of an edge portion of the obverse side mounting surface231. As described later, the third rigid board23is fixed to the pedestal4at the edge portion thereof via an adhesive. Therefore, it is hard for the edge portion of the third rigid board23to be deformed, and therefore the unwanted vibration is difficult to occur. Therefore, by disposing the angular velocity sensor713and the acceleration sensor72at such places, the angular velocity and the acceleration can more accurately be detected.

Further, by mounting the angular velocity sensor713and the acceleration sensor72on the reverse side mounting surface232, it is possible to elongate the distance from the microcontroller76in the condition in which the mounting board2is fixed to the casing10. Further, it is possible to make the ground layer provided to the third rigid board23be located between the angular velocity sensor713and the acceleration sensor72, and the microcontroller76. Therefore, it is possible to prevent radiation noise generated from the microcontroller76from exerting a harmful influence on the angular velocity sensor713and the acceleration sensor72to thereby improve the detection accuracy of the angular velocity sensor713and the acceleration sensor72.

On the obverse side mounting surface241of the fourth rigid board24, there is mounted the microcontroller76, and on a reverse side mounting surface242, there are mounted the nonvolatile memory77and the direction sensor78.

The microcontroller76is larger in size than the other electronic components7(the nonvolatile memory77and the direction sensor78) mounted on the fourth rigid board24. Therefore, it is preferable to dispose the microcontroller76at a center portion of the obverse side mounting surface241. Thus, it is possible to effectively use the microcontroller76as a reinforcement member for reinforcing the rigidity of the fourth rigid board24. Therefore, the unwanted vibration due to the flexural deformation of the fourth rigid board24can be suppressed, and the unwanted vibration can be prevented from being transmitted to the angular velocity sensors711through713, and therefore the accuracy of the detection of the angular velocity by the angular velocity sensors711through713is improved.

Further, by mounting the direction sensor78on the mounting surface opposite to the surface on which the microcontroller76is mounted, the radiation noise generated from the microcontroller76can be blocked by the ground layer of the fourth rigid board24, and therefore, the radiation noise (the magnetic field) can effectively be prevented from exerting a harmful influence on the direction sensor78. Therefore, the detection accuracy of the direction sensor78can be improved.

On a reverse side mounting surface252of the fifth rigid board25, there is mounted the connector79.

Hereinabove, the arrangement of the electronic components7is described in detail.

In the mounting board2, an analog circuit composed of the power supply circuit73, the amplifier circuit74, the analog/digital converter circuit75, and so on is provided to the third rigid board23, and a digital circuit composed of the microcontroller76, the nonvolatile memory77, and so on is provided to the fourth rigid board24. By forming the analog circuit and the digital circuit on the respective rigid boards separated from each other as described above, the generation and the transmission of the noise can effectively be suppressed, and thus the detection accuracy of the sensor device1is further enhanced.

The angular velocity sensors711through713are not particularly limited providing the angular velocity can be detected, and known uniaxial detection type of angular velocity sensors can be used therefor. As such angular velocity sensors711through713, a sensor having a vibrator element5shown inFIG. 4, for example, can be used.

The vibrator element5is made of a quartz crystal (a piezoelectric material). Further, the vibrator element5has a base section51, a pair of detecting vibrator arms52,53extending in a vertical direction of a sheet of the drawing from both sides of the base section51, a pair of connection arms54,55extending in a lateral direction of the sheet from both sides of the base section51, and pairs of driving vibrator arms56,57,58, and59extending in the vertical direction of the sheet from both sides of respective tip portions of the connection arms54,55. Further, a surface of each of the detecting vibrator arms52,53is provided with a detecting electrode (not shown), and a surface of each of the driving vibrator arms56,57,58, and59is provided with a driving electrode (not shown).

In such a vibrator element5, in the condition in which the driving vibrator arms56,58and the driving vibrator arms57,59are made to vibrate by applying a voltage to the driving electrodes so as to repeat to come closer to and get away from each other, when an angular velocity ω around a normal line A (a detection axis A) of the vibrator element5is applied, the Coriolis force is applied to the vibrator element5, and the vibration of the detecting vibrator arms52,53is excited. Then, by detecting the distortion in the detecting vibrator arms52,53, which is caused by the vibration of the detecting vibrator arms52,53, by the detecting electrodes, the angular velocity applied to the vibrator element5can be obtained.

The angular velocity sensors711through713each having the configuration described above are mounted on the first through third rigid boards21through23, respectively, so that the thickness direction of the rigid board corresponds to the detection axis.

Casing

As shown inFIG. 2, the casing10has the mounting member3, the pedestal (a first lid member)4, and a lid member (a second lid member)8. In other words, the mounting member3constitutes a part of the casing10. Since the number of components of the sensor device1can be reduced by using the mounting member3as the part of the casing as described above, the downsizing of the sensor device1can be achieved.

Such a casing10as described above has a fixation surface (a first fixation surface)101for fixing the first rigid board21, a fixation surface (a second fixation surface)102for fixing the second rigid board22, a fixation surface (a third fixation surface)103for fixing the third rigid board23, a fixation surface (a fourth fixation surface)104for fixing the fourth rigid board24, and a fixation surface (a fifth fixation surface)105for fixing the fifth rigid board25.

Hereinafter, the mounting member3, the pedestal4, and the lid member8will sequentially be explained.

Mounting Member

As shown inFIG. 2, the mounting member3has a main body31, and a through hole32opened in an upper surface and a lower surface of the main body31. A space in the through hole32functions as a housing space for housing the electronic components7.

In the present embodiment, the outer shape of the main body31in the x-y plan view is a rectangle. Further, the upper surface and the lower surface are both planes parallel to the x-y plane. Further, the through hole32extends in the z-axis direction and has a roughly rectangular lateral cross-sectional shape.

An inner surface33exposed to the through hole32is composed of a pair of planes331,333parallel to the y-z plane and a pair of planes332,334parallel to the x-z plane. Among these four planes331through334, the plane331constitutes the fixation surface101, the plane332constitutes the fixation surface102, and the plane333constitutes the fixation surface105.

As shown inFIG. 2, to the fixation surface101, there is fixed the first rigid board21with the reverse side mounting surface212facing the fixation surface101. Thus, the angular velocity sensor711is fixed indirectly to the fixation surface101via the first rigid board21. Since the fixation surface101is the plane parallel to the y-z plane as described above, in the state in which the first rigid board21is fixed to the fixation surface101, the detection axis of the angular velocity sensor711becomes parallel to the x axis. As described above, only by fixing the first rigid board21to the fixation surface101, positioning of the angular velocity sensor711with respect to the casing10can easily be performed.

Further, by locating the angular velocity sensor711on the inner side of the first rigid board21, the external magnetic field can be blocked by the ground layer provided to the first rigid board21, and therefore, the influence of the external magnetic field is reduced, and thus the detection accuracy of the angular velocity sensor711is improved.

Although the method of fixing the first rigid board21to the fixation surface101is not particularly limited, it is preferable to use both of fixation with an adhesive and fixation with screws. Thus, the fixation of the first rigid board21to the fixation surface101can surely be performed. Further, since a layer of the adhesive intervenes between the mounting member3and the first rigid board21, the adhesive absorbs and eases the vibration transmitted from the mounting member3to thereby suppress the unwanted vibration of the first rigid board21. As a result, the detection accuracy of the sensor device1is further improved.

As shown inFIG. 2, to the fixation surface102, there is fixed the second rigid board22with a reverse side mounting surface222facing the fixation surface102. Thus, the angular velocity sensor712is fixed indirectly to the fixation surface102via the second rigid board22. Since the fixation surface102is the plane parallel to the x-z plane as described above, in the state in which the second rigid board22is fixed to the fixation surface102, the detection axis of the angular velocity sensor712becomes parallel to the y axis. As described above, only by fixing the second rigid board22to the fixation surface102, positioning of the angular velocity sensor712with respect to the casing10can easily be performed.

Further, by locating the angular velocity sensor712on the inner side of the second rigid board22, the external magnetic field can be blocked by the ground layer provided to the second rigid board22, and therefore, the influence of the external magnetic field is reduced, and thus the detection accuracy of the angular velocity sensor712is improved.

Although the method of fixing the second rigid board22to the fixation surface102is not particularly limited, it is preferable to use both of fixation with an adhesive and fixation with screws. Thus, the fixation of the second rigid board22to the fixation surface102can surely be performed. Further, since a layer of the adhesive intervenes between the mounting member3and the second rigid board22, the adhesive absorbs and eases the vibration transmitted from the mounting member3to thereby suppress the unwanted vibration of the second rigid board22. As a result, the detection accuracy of the sensor device1is further improved.

As shown inFIG. 2, to the fixation surface105, there is fixed the fifth rigid board25with the reverse side mounting surface252facing the fixation surface105. Further, the mounting member3is provided with a through hole35penetrating the fixation surface105and an outer peripheral surface, and the fifth rigid board25is fixed to the fixation surface105with the connector79inserted in the through hole35. Thus, the connector79is exposed to the outside of the sensor device1via the through hole35, and an output of signals from the sensor device1can easily be achieved. It should be noted that it is preferable for the fifth rigid board25to be fixed to the fixation surface105so as to cover an opening of the through hole35. Thus, infiltration of dust and so on into the casing can be prevented to thereby keep the reliability of the sensor device1.

Although the method of fixing the fifth rigid board25to the fixation surface105is not particularly limited, it is preferable to use both of fixation with an adhesive and fixation with screws. Thus, the fixation of the fifth rigid board25to the fixation surface105can surely be performed. Further, since a layer of the adhesive intervenes between the mounting member3and the fifth rigid board25, the adhesive absorbs and eases the vibration transmitted from the mounting member3to thereby suppress the unwanted vibration of the fifth rigid board25. As a result, the detection accuracy of the sensor device1is further improved.

Although a constituent material of such a mounting member3is not particularly limited, a material with a damping property is preferably used. Thus, the unwanted vibration of the mounting member3can be suppressed to thereby improve the detection accuracy of the angular velocity sensors711through713and so on. As such a material as described above, there can be cited various types of damping alloys such as a magnesium alloy, an iron alloy, a copper alloy, a manganese alloy, and a Ni—Ti alloy.

The pedestal4is fixed to the mounting member3so as to block a lower opening of the mounting member3. The method of fixing the pedestal4to the mounting member3is not particularly limited, and the fixation method of using an adhesive, for example, can be used.

Such a pedestal4has a plate-like shape having the thickness direction corresponding to the z-axis direction, and has a lower surface and an upper surface41parallel to the x-y plane. Further, the upper surface41constitutes the fixation surface103for fixing the third rigid board23.

As shown inFIG. 2, to the fixation surface103, there is fixed the third rigid board23with the reverse side mounting surface232facing the fixation surface103. Thus, the angular velocity sensor713is fixed indirectly to the fixation surface103via the third rigid board23. Since the fixation surface103is the plane parallel to the x-y plane as described above, in the state in which the third rigid board23is fixed to the fixation surface103, the detection axis of the angular velocity sensor713becomes parallel to the z axis. As described above, only by fixing the third rigid board23to the fixation surface103, positioning of the angular velocity sensor713with respect to the casing10can easily be performed.

Further, the pedestal4has a recessed section42opened in the fixation surface103. The recessed section42is opened in a center portion of the fixation surface103except an edge portion thereof, and is not opened in a side surface of the pedestal4. In other wards, the recessed section42has a trough shape surrounded by sidewalls in the periphery thereof.

In the condition of fixing the third rigid board23to the fixation surface103, the angular velocity sensor713and the acceleration sensor72mounted on the reverse side mounting surface232of the third rigid board23are located in the recessed section42. In other words, the recessed section42forms a clearance for preventing the angular velocity sensor713and the acceleration sensor72from having contact with the pedestal4. By forming such a recessed section42as described above, a space of the pedestal4can be used effectively to thereby achieve downsizing (low-profiling, reduction in height) of the sensor device1.

Further, the recessed section42is filled with an infill9, and a gap between the pedestal4and the third rigid board23is filled with the infill9. Thus, the third rigid board23(the angular velocity sensor713, the acceleration sensor72) and the connection sections261,262, and263extending from the third rigid board23are fixed, and thus the unwanted vibration can effectively be prevented from occurring in the third rigid board23. Therefore, the detection accuracy of the sensor device1is improved.

As a constituent material of the infill9, those having an insulating property are preferable. The material is not particularly limited, and there can be cited as the material, for example, polyolefin such as polyethylene, or polypropylene, ethylene-propylene copolymer, polyvinyl chloride, polystyrene, polyamide, polyimide, polycarbonate, poly-(4-methylpentene-1), ionomer, acrylic resin, polymethylmethacrylate, acrylonitrile-butadiene-styrene copolymer (ABS resin), acrylonitrile-styrene copolymer (AS resin), butadiene-styrene copolymer, polyester such as polyethylene terephthalate (PET), or polybutylene terephthalate (PBT), polyether, polyetherketone (PEK), polyether ether ketone (PEEK), polyetherimide, polyacetal (POM), polyphenylene oxide, polysulfone, polyethersulfone, polyphenylene sulfide, polyarylate, aromatic polyester (liquid crystal polymer), fluorinated resin such as polytetrafluoroethylene or polyvinylidene fluoride, epoxy resin, phenol resin, urea resin, melamine resin, silicone resin, polyurethane resin, and so on, copolymers, polymer blends, and polymer alloys having any one of these compounds as a primary constituent, and these materials can be used alone or in combination.

The constituent material of such a pedestal4is not particularly limited, and substantially the same materials as those of the mounting member3can be cited for example.

The lid member8is fixed to the mounting member3so as to block an upper opening of the mounting member3. The method of fixing the lid member8to the mounting member3is not particularly limited, and the fixation method of using an adhesive, for example, can be used.

Such a lid member8as described above has a plate-like shape having the thickness direction corresponding to the z-axis direction, and has a lower surface81parallel to the x-y plane. The lower surface81constitutes the fixation surface104for fixing the fourth rigid board24.

As shown inFIG. 2, to the fixation surface104, there is fixed the fourth rigid board24with the reverse side mounting surface242facing the fixation surface104. Since the fixation surface104is a plane parallel to the x-y plane as described above, the rigid board24fixed to the fixation surface104is opposed to the third rigid board23in the z-axis direction, and at the same time disposed in parallel to the third rigid board23. By disposing the third and fourth rigid boards23,24so as to overlap each other in the z-axis direction, downsizing of the sensor device1in the x-y plan view can be achieved. In addition, by making the third and fourth rigid boards23,24parallel to each other, the length in the z-axis direction (the height) of the sensor device1can be reduced, and in this regard, downsizing of the sensor device1can also be achieved.

Further, the lid member8has a recessed section82opened in the fixation surface104. The recessed section82is opened in a center portion of the fixation surface104except an edge portion thereof, and is not opened in a side surface of the lid member8. In other wards, the recessed section82has a trough shape surrounded by sidewalls in the periphery thereof.

In the condition of fixing the fourth rigid board24to the fixation surface104, the nonvolatile memory77and the direction sensor78mounted on the reverse side mounting surface242of the fourth rigid board24are located in the recessed section82. In other words, the recessed section82forms a clearance for preventing the nonvolatile memory77and the direction sensor78from having contact with the lid member8. By forming such a recessed section82as described above, a space of the lid member8can be used effectively, and thus downsizing (low-profiling, reduction in height) of the sensor device1can be achieved. It should be noted that it is also possible to fill such a recessed section82as described above with the infill9as in the case of the recessed section42described above.

A constituent material of such a lid member8is not particularly limited, and substantially the same materials as those of the mounting member3can be cited for example.

Hereinabove, the sensor device1is described in detail.

According to such a sensor device1as described above, since the mounting board2is fixed directly to the casing10, the number of components is small, and the downsizing can be achieved accordingly. Further, since the positioning of the rigid boards21through25can be performed with ease and accuracy, excellent detection performance and reliability can be exerted.

It should be noted that when mounting the sensor device1on the circuit board such as a motherboard, by using two side surfaces4a,4bof the pedestal4perpendicular to each other as the reference, it is possible to easily point the detection axes of the angular velocity sensors711,712to the desired directions. Specifically, the side surface4ais a plane parallel to the detection axis of the angular velocity sensor712, and the side surface4bis a plane parallel to the detection axis of the angular velocity sensor711. Therefore, by performing the positioning with respect to the circuit board using the side surfaces4a,4bas the reference, it is possible to point the detection axes of the angular velocity sensors711,712to the desired directions with ease and accuracy.

Second Embodiment

Then, a sensor device according to a second embodiment of the invention will be explained.

FIG. 5is a cross-sectional view showing the sensor device according to the second embodiment of the invention.

Hereinafter, the second embodiment will be described with a focus mainly on differences from the first embodiment described above, and explanations regarding substantially the same matters will be omitted. The sensor device according to the present embodiment is substantially the same as the sensor device according to the first embodiment except that the configuration of the casing is different. It should be noted that the constituents identical to those of the first embodiment described above are denoted by the same reference symbols.

As shown inFIG. 5, a casing10A provided to the sensor device1according to the present embodiment has a mounting member3A and the lid member8. In other words, in the present embodiment, the pedestal4of the first embodiment described above is formed integrally with the mounting member3.

The mounting member3A has a main body31A, and a recessed section32A opened in an upper surface of the main body31A. A space in the recessed section32A functions as a housing space for housing the electronic components7. The recessed section32A has a rectangular lateral cross-sectional shape.

An inner surface33A exposed to the recessed section32A is composed of a pair of planes331A,333A parallel to the y-z plane, a pair of planes332A,334A parallel to the x-z plane, and a plane335A parallel to the x-y plane. Among these five planes331A through335A, the plane331A constitutes the fixation surface101, the plane332A constitutes the fixation surface102, the plane333A constitutes the fixation surface105, and the plane335A constitutes the fixation surface103.

To the fixation surface101, there is fixed the first rigid board21with a reverse side mounting surface212facing the fixation surface101. Thus, the detection axis of the angular velocity sensor711becomes parallel to the x axis.

To the fixation surface102, there is fixed the second rigid board22with the reverse side mounting surface222facing the fixation surface102. Thus, the detection axis of the angular velocity sensor712becomes parallel to the y axis.

To the fixation surface103, there is fixed the third rigid board23with the reverse side mounting surface232facing the fixation surface103. Thus, the detection axis of the angular velocity sensor713becomes parallel to the z axis. Further, the mounting member3A has a recessed section39A opened in the fixation surface103. The recessed section39A is opened at a center portion of the fixation surface103except an edge portion thereof, and in the condition of fixing the third rigid board23to the fixation surface103, the angular velocity sensor713and the acceleration sensor72are located in the recessed section39A. Further, the recessed section39A is filled with the infill9.

To the fixation surface105, there is fixed the fifth rigid board25with the reverse side mounting surface252facing the fixation surface105. Further, the mounting member3A is provided with the through hole35penetrating the fixation surface105and the outer peripheral surface, and the fifth rigid board25is fixed to the fixation surface105with the connector79inserted in the through hole35.

According also to the second embodiment described hereinabove, substantially the same advantage as in the first embodiment described above can be obtained.

Third Embodiment

Then, a sensor device according to a third embodiment of the invention will be explained.

FIG. 6is a cross-sectional view of the sensor device according to the third embodiment of the invention,FIGS. 7A and 7Bare development diagrams of a mounting board provided to the sensor device shown inFIG. 6, andFIG. 8is a cross-sectional view showing a modified example of the sensor device shown inFIG. 6.

Hereinafter, the third embodiment will be described with a focus mainly on differences from the embodiments described above, and explanations regarding substantially the same matters will be omitted.

The sensor device according to the present embodiment is substantially the same as the sensor device according to the first embodiment except that mounting positions of the angular velocity sensors with respect to the mounting board2are different. It should be noted that the constituents identical to those of the first embodiment described above are denoted by the same reference symbols.

As shown inFIGS. 7A and 7B, in the mounting board2according to the present embodiment, the angular velocity sensor711is mounted on the reverse side mounting surface212of the first rigid board21, and the angular velocity sensor712is mounted on the reverse side mounting surface222of the second rigid board22.

Further, as shown inFIG. 6, the first mounting board21is fixed to the fixation surface101with the angular velocity sensor711located on the fixation surface101side and directly fixed to the fixation surface101with an adhesive or the like. Similarly, the second mounting board22is fixed to the fixation surface102with the angular velocity sensor712located on the fixation surface102side and directly fixed to the fixation surface102with an adhesive or the like.

It should be noted that as a modified example of the present embodiment, as shown inFIG. 8, it is also possible for the fixation surface101to have a recessed section101aat a position corresponding to the angular velocity sensor711, and house a part of the angular velocity sensor711in the recessed section101a. The depth of the recessed section101ais set to be slightly smaller than the thickness of the angular velocity sensor711in order for preventing the first mounting board21and the fixation surface101from having contact with each other.

Similarly, it is also possible for the fixation surface102to have a recessed section102aat a position corresponding to the angular velocity sensor712, and house a part of the angular velocity sensor712in the recessed section102a. The depth of the recessed section102ais set to be slightly smaller than the thickness of the angular velocity sensor712in order for preventing the second mounting board22and the fixation surface102from having contact with each other.

By providing the recessed sections101a,102ato the fixation surfaces101,102as described above, the space of the mounting member3can effectively be used, and the downsizing of the sensor device1can be achieved.

According also to the third embodiment described hereinabove, substantially the same advantage as in the first embodiment described above can be obtained.

2. Electronic Apparatus

The sensor device1described above can be incorporated in a variety of electronic apparatuses. The electronic apparatus according to an embodiment of the invention equipped with the sensor device1will hereinafter be described.FIG. 9is a diagram showing an example of a configuration of an electronic apparatus500equipped with the sensor device1. The electronic apparatus500is not particularly limited, and there can be cited as the electronic apparatus, for example, a digital camera, a video camera, a car navigation system, a cellular phone, a mobile PC, a robot, a gaming machine, and a gaming controller.

The electronic apparatus500shown inFIG. 9has a sensor module510including the sensor device1, a processing section520, a memory530, an operating section540, and a display section550. These constituents are connected to each other via a bus560. The processing section (e.g., a CPU and an MPU)520performs control of the sensor module510and so on and the overall control of the electronic apparatus500. Further, the processing section520performs a process based on angular velocity information detected by the sensor module510. For example, the processing section520performs a process for blurring correction, posture control, and GPS autonomous navigation based on the angular velocity information. The memory530stores a control program and a variety of data, and further, functions as a working area and a data storage area. The operating section540is for a user to operate the electronic apparatus500. The display section550is for displaying a variety of information to the user.

Although the sensor device and the electronic apparatus according to the invention are hereinabove described based on the embodiments shown in the accompanying drawings, the invention is not limited thereto, but the configuration of each of the constituents can be replaced with one having an arbitrary configuration with an equivalent function.

Further, although in the embodiments described above there is explained the configuration of mounting the three angular velocity sensors on the mounting board, the number of angular velocity sensors is not limited thereto, and can be one or two. Further, the number of rigid boards can also be changed in accordance with the number of angular velocity sensors.

Further, although in the embodiments described above the mounting board is formed of the rigid-flexible board, the configuration of the mounting board is not limited thereto, and it is also possible to configure the mounting board with a plurality of rigid boards not connected to each other. In this case, it is possible to electrically connect the rigid boards to each other using connectors and so on after fixing the rigid boards to the mounting member.

Further, although in the embodiments described above the configuration of fixing the electronic components mounted on the mounting board to the casing is explained, the configuration is not limited thereto, and it is also possible to eliminate the mounting board, and directly fix the electronic components to the casing. In this case, it is possible to separately form wires or the like for electrically connecting the electronic components to each other.

The entire disclosure of Japanese Patent Application No. 2011-154502, filed Jul. 13, 2011 is expressly incorporated by reference herein.