JPH07225241A - Semiconductor acceleration sensor unit - Google Patents

Abstract

PURPOSE:To protect an acceleration sensor of a semiconductor acceleration sensor unit from falling shock. CONSTITUTION:Four corners of square frame are made thin-walled and a shock absorbing supporter 5 in which three slits 15a and 15c are provided parallelly in a vertical direction is formed in respective corners. In addition, the outer circumferential part of the side of the supporter 5 facing a mounting substrate 2 is recessed in order to form a thin-walled part 17. After the substrate 2 is inserted into the central slit so that it may be supported by the supporter 5, it is included in a package body 3 and covered with a cover 4, further it is packaged in a resin case 11, resulting in a semiconductor acceleration sensor unit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor acceleration sensor unit. Specifically, the present invention relates to a semiconductor acceleration sensor unit in which a mounting board on which a semiconductor acceleration sensor is mounted is mounted on a package such as a resin case or a metal case.

[0002]

2. Description of the Related Art FIG. 9 shows a sectional view of a conventional semiconductor acceleration sensor unit G. 51 is a semiconductor acceleration sensor, 52
Is a mounting board on which a detection circuit and the like are mounted, and the acceleration sensor 51 is mounted on the mounting board 52 and then mounted on the mounting board 5.
2 is a package 53 such as a resin case or a metal case directly
And the cover 54 was put on the package 53. Further, the sensor signal processed by the detection circuit or the like can be taken out of the unit through the output terminal (harness) 55.

[0003]

However, in such a conventional structure, if the acceleration sensor unit is accidentally dropped during transportation of the acceleration sensor unit or when the acceleration sensor unit is attached to an automobile or the like, the impact of the drop may occur. Therefore, there is a problem that the semiconductor acceleration sensor is damaged.

The present invention has been made in view of the drawbacks of the above-mentioned conventional examples, and an object of the present invention is to elastically package a circuit board on which an acceleration sensor is mounted into a package such as a resin case or a metal case. The support is provided to alleviate the above-mentioned problems by mitigating a mechanical impact such as a drop impact.

[0005]

According to the semiconductor acceleration sensor unit of the present invention, the semiconductor acceleration sensor unit in which the mounting substrate on which the semiconductor acceleration sensor is mounted is housed in a package such as a metal case or a resin case has elasticity. It is characterized in that the mounting board is housed in the package by supporting the mounting board on a shock absorbing support.

Further, a first slit for supporting the mounting board on the shock absorbing support and a second slit in parallel with the first slit in at least one of the vertical direction may be formed. Good. At this time, the first
It is preferable to form a thin portion that is formed by denting the outer surface of the shock absorbing support body by being positioned on the side surface of the mounting substrate supported by the slit, and it is desirable to provide a protrusion on the outer surface of the thin portion. .

Further, a shock absorbing material having elasticity may be provided on the upper surface of the semiconductor acceleration sensor, and at least the shock absorbing material may be provided on the upper surface of the mounting substrate. Further, a shock absorber may be provided on the inner surface of the package.

Further, in the above acceleration sensor unit, the package is provided with a feedthrough capacitor, and the sensor signal is taken out of the unit from the electrode terminal of the feedthrough capacitor inserted into the through hole provided in the mounting board. Inside the unit, the electrode terminal and the sensor signal output portion on the mounting board are electrically connected by a flexible lead wire. Further, the electrode terminal and the sensor signal extracting portion may be electrically connected by a metal plate having a spring property or a coil-shaped conductor.

Further, in the above semiconductor acceleration sensor unit, it is preferable that the inside of the package is almost filled with a gel-like substance.

[0010]

In the semiconductor acceleration sensor unit of the present invention, since the mounting substrate is supported by the shock absorbing support and then housed in the package, even if a large shock such as a drop shock is applied to the unit, the shock applied is a shock. It is possible to prevent a large impact force which is absorbed by the elastic deformation of the absorption support body from being directly applied to the mounting substrate. Therefore, the acceleration sensor will not be damaged even by a mishandling or a large shock during use.

For this purpose, for example, the first slit for supporting the mounting substrate on the shock absorbing support and the second slit parallel to the first slit in at least one of the vertical direction of the first slit.
Slits can be provided. In this case, the shock absorbing support between the first slit and the second slit is elastically deformed in the vertical direction, so that the vertical shock applied to the acceleration sensor unit can be further mitigated.

Further, since the thin portion is formed by denting the outer side surface of the shock absorbing support located on the side surface of the mounting substrate, the thin portion is easily elastically deformed toward the outside of the shock absorbing support. can do. Therefore, the lateral impact applied to the acceleration sensor unit is further alleviated by the elastic deformation of the thin portion.

Further, since the shock absorber is provided on the upper surface of the acceleration sensor, the acceleration sensor can be protected from a very large vertical shock such that the acceleration sensor directly hits the inner surface of the package. Further, even if a shock absorbing material is provided on the inner surface of the package, the acceleration sensor can be similarly protected. Further, a shock absorbing material may be provided on at least the upper surface of the mounting board.

Further, in the above-mentioned acceleration sensor unit, in which the package is provided with a feedthrough capacitor, and the sensor signal is taken out of the unit from the electrode terminal of the feedthrough capacitor which is inserted into the through hole provided in the mounting substrate, is mounted inside the unit If the sensor signal extracting portion on the substrate and the electrode terminal are electrically connected to each other by an elastically deformable material such as a flexible lead wire, a metal plate having a spring property, or a coil-shaped conductor, Even if the mounting substrate is displaced in the up-down direction or the left-right direction due to the elastic deformation, the connection between the sensor signal extracting portion and the electrode terminal is not disconnected.

If the inside of the package is filled with a gel-like substance, the impact applied to the unit can be further absorbed.

[0016]

FIG. 1 shows an acceleration sensor unit A which is an embodiment of the present invention. 1A is a sectional view of the acceleration sensor unit A, and FIG. 1B is a partially cutaway schematic plan view showing the inside of the acceleration sensor unit A. Reference numeral 1 is a semiconductor acceleration sensor, 2 is a mounting substrate on which a detection circuit and the like (not shown) are configured, 3 is a package body such as a metal case or resin case, and 5 is a shock absorbing support. Acceleration sensor 1
After being mounted on the mounting substrate 2, the mounting substrate 2 is supported by the shock absorbing support 5 and housed in the package body 3, and the package body 3 is covered with the cover 4. Further, a feedthrough capacitor 6 is provided on the bottom surface of the package body 3, and an electrode rod 8 of the feedthrough capacitor 6 penetrating a hole 7 opened in the mounting substrate 2 is provided in the package body 3. The feedthrough capacitor 6 is provided to prevent radio wave interference given to the outside from the acceleration sensor unit A or given to the acceleration sensor unit A from the outside. One end of an elastic thin plate metal lead 9 electrically connected to the detection circuit is fixed near the tip of the electrode rod 8, and the sensor signal detected by the detection circuit is transmitted from the metal lead 9 to the electrode rod 8. And through feedthrough capacitor 6,
It can be taken out by a connector 10 electrically connected to the other end of the electrode rod 8. In addition to this, the metal lead 9 may be made of an electrically conductive material such as a flexible lead wire or a coil-shaped conductor that is elastically deformable.
The package body 3 and the cover 4 configured in this way are further housed in the resin case 11, and the resin cover 1
Covered by 2. And the acceleration sensor unit A
Can be attached to a system such as an automobile by a metal bracket 13.

2 (a) and 2 (b) are a perspective view and a sectional view, respectively, showing the shock absorbing support 5. As shown in FIG. 2 (a), the shock absorbing support 5 is in the shape of a rectangular frame, and four corners formed thinly are provided with three slits 15a, 15b, 15c in parallel in the vertical direction. It is provided. The shock absorbing support 5 is formed of a material such as rubber or resin having elasticity that can absorb shock, does not absorb vibration in a frequency band such as acceleration and vibration to be measured, and has a frequency of shock such as drop shock. A material that can absorb the vibration in the band is particularly preferable. The two support portions 16 sandwiched by the upper and lower three slits 15a, 15b and 15c of the shock absorbing support 5 can be elastically deformed in the vertical direction respectively, and the central slit 15b among the three slits is The corners of the mounting board 2 are respectively inserted, and the mounting board 2 is supported by the shock absorbing support 5 such that the mounting board 2 is sandwiched by the two supporting portions 16. Further, a thin portion 17 is provided by recessing the outer peripheral side surface of the shock absorbing support 5 in accordance with the position of the central slit 15b into which the mounting board 2 is inserted, that is, the position where the side surface of the mounting board 2 abuts.

However, when a shock is applied to the acceleration sensor unit A in the vertical direction, that is, the Z-axis direction, the mounting substrate 2 vibrates in the Z-axis direction. At this time, the support portion 16 of the shock absorbing support 5 can be elastically vibrated in the Z-axis direction by the upper and lower slits 15a and 15c, so that the shock applied to the acceleration sensor unit A in the Z-axis direction can be softened. You can Further, the electrode rod 8 and the mounting substrate 2 are connected by the metal lead 9 having elasticity, and the mounting substrate 2 is
Even if it vibrates in the axial direction, it can freely vibrate due to the elastic deformation of the metal lead 9, so there is no fear of disconnection from the electrode rod 8.

When a shock is applied to the acceleration sensor unit A in the left-right direction, that is, the X-axis direction, the mounting substrate 2 vibrates in the X-axis direction. At this time, the thin wall portion 17 of the shock absorbing support 5 formed on the side surface of the mounting substrate 2 has the shock absorbing support 5
By virtue of the elastic deformation of, the vibration in the X axis direction can be softened, and the impact applied to the acceleration sensor unit A in the X axis direction can be softened.

If the mounting substrate 2 is supported by the shock absorbing support 5 as described above and the acceleration sensor unit A is constructed,
The acceleration sensor 1 can be protected from a shock applied to the unit, and damage due to a mistake in handling can be reduced. By the way, the frequency of the vibration applied by the drop impact is much higher than the frequency of the vibration applied by the acceleration to be measured, and the vibration applied by the acceleration is hardly absorbed by the shock absorbing support 5 and is used for shock absorption. The influence of the support 5 on the measurement of the acceleration can be almost ignored.

FIG. 3 is a cross-sectional view showing an acceleration sensor unit B which is another embodiment of the present invention. The thin portion 17 of the shock absorbing support 5 has a protrusion 1 extending toward the outer periphery.
8 are provided. As shown in FIG. 4A, the protrusion 18 is provided with a sufficient gap between the protrusion 18 and the package body 3, and when a drop impact in the X-axis direction is applied, the mounting substrate 2 is pushed in the X-axis direction. As a result, the thin portion 17 is elastically deformed in the outer peripheral direction (FIG. 4B). Further, when a large impact is applied in the X-axis direction, the mounting substrate 2 is pressed against the package body 3. At this time, as shown in FIG. 4C, the thin portion 17 is largely elastically deformed in the outer peripheral direction to project. The portion 18 hits the package body 3, and the impact applied to the mounting substrate 2 at the time of collision is softened by the elastic deformation of the protrusion 18. Therefore, even when a larger impact is applied to the unit, the impact applied to the acceleration sensor 1 is reduced, and damage to the acceleration sensor 1 can be prevented more effectively.

FIG. 5 shows a sectional view of an acceleration sensor unit C which is still another embodiment of the present invention. A shock absorber 19 having elasticity such as rubber or resin is arranged on the upper surface of the acceleration sensor 1. By disposing the shock absorber 19 on the upper surface of the acceleration sensor 1 as described above, even when a larger shock in the Z-axis direction is applied, the shock absorber 19 and the cover 4 are provided.
The impact is absorbed by the collision with the inner surface of the acceleration sensor 1
The impact applied to can be reduced.

Further, FIG. 6 shows an acceleration sensor unit D which is still another embodiment. A shock absorber 19 is arranged on the upper and lower surfaces of the mounting board 2 and the shock absorbing unit 19 is arranged on the upper surface of the mounting board 2. The upper end of the body 19 is formed at least higher than the upper surface of the acceleration sensor 1. Also in this embodiment, the shock in the Z-axis direction is absorbed by the shock absorber 19. The shock absorber 19 is arranged on the inner surface of the package body 3 to prevent a strong shock from being applied to the mounting substrate 2 as in the acceleration sensor unit E shown in FIG. It may be possible to prevent the collision with the acceleration sensor 1.

FIG. 8 shows a sectional view of an acceleration sensor unit F which is still another embodiment of the present invention. In the package body 3 of the acceleration sensor unit F, the gel substance 2
Zero is almost filled, and the impact applied to the acceleration sensor unit F is absorbed by the gel substance 20, and the impact applied to the acceleration sensor 1 can be reduced. Since the gel substance 20 attenuates vibrations in a high frequency region such as impact, the impact applied to the acceleration sensor 1 can be effectively reduced by filling the inside of the package body 3. The gel-like substance 20 is preferably an insulating substance, and for example, silicone resin can be used. In addition,
A cover 1a is provided on the upper surface of the acceleration detection unit (not shown) of the acceleration sensor 1 so that the gel substance 20 does not hinder the displacement or vibration of the acceleration detection unit. Further, it is more effective to provide the shock absorber 19 on the upper surface of the acceleration sensor 1 or the projection 18 on the thin portion 17.

[0025]

According to the semiconductor acceleration sensor unit of the present invention, the acceleration sensor can be protected from a drop impact applied to the acceleration sensor unit by elastic deformation of the impact absorbing support supporting the mounting substrate.

Further, for example, if the shock absorbing support is provided with a first slit for supporting the mounting substrate and a second slit in the vertical direction of the first slit, the second slit being parallel to the first slit, the first slit and the first slit are provided. The shock absorbing support between the two slits is elastically deformed in the vertical direction, and the vertical shock applied to the acceleration sensor unit can be absorbed.

When a thin portion is formed by denting the outer surface of the shock absorbing support located on the side surface of the mounting board, the lateral deformation of the acceleration sensor unit is absorbed by elastic deformation of the thin portion. be able to.

Further, since the shock absorbing material is provided on the upper surface of the acceleration sensor, the inner surface of the package, or at least the upper surface of the mounting substrate, the acceleration sensor can be operated even from a very large vertical shock such that the acceleration sensor directly hits the inner surface of the package. Can be protected.

Further, in the above acceleration sensor unit having a structure in which a through capacitor is provided in the package and the sensor signal is taken out of the unit from the electrode terminal of the through capacitor inserted into the through hole provided in the mounting substrate, the acceleration sensor unit is mounted inside the unit. If the sensor signal extracting portion on the substrate and the electrode terminal are electrically connected by an elastically deformable material such as a flexible lead wire, a metal plate having spring properties or a coil-shaped conductor, The connection with the electrode terminal will not be disconnected.

Further, if the inside of the package is filled with a gel-like substance, the acceleration sensor can be protected from the shock applied to the unit.

[Brief description of drawings]

1A is a sectional view showing a semiconductor acceleration sensor unit according to an embodiment of the present invention, and FIG. 1B is a partially cutaway schematic plan view showing the internal structure of the semiconductor acceleration sensor unit.

2 (a) and 2 (b) are a perspective view and a cross-sectional view, respectively, showing the same impact absorbing support.

FIG. 3 is a sectional view showing a semiconductor acceleration sensor unit which is another embodiment of the present invention.

FIG. 4 is an explanatory view showing the movement of the shock absorbing support body of the present invention.

FIG. 5 is a sectional view showing a semiconductor acceleration sensor unit which is still another embodiment of the present invention.

FIG. 6 is a sectional view showing a semiconductor acceleration sensor unit which is still another embodiment of the present invention.

FIG. 7 is a sectional view showing a semiconductor acceleration sensor unit which is still another embodiment of the present invention.

FIG. 8 is a sectional view showing a semiconductor acceleration sensor unit which is still another embodiment of the present invention.

FIG. 9 is a cross-sectional view showing a semiconductor acceleration sensor unit which is a conventional example.

[Explanation of symbols]

 1 Semiconductor Acceleration Sensor 3 Package Body 5 Shock Absorbing Support 8 Electrode Rod 15a, 15b, 15c Slit 17 Thin Wall 20 Gel-like Material

Claims (11)

[Claims] 1. In a semiconductor acceleration sensor unit in which a mounting board on which a semiconductor acceleration sensor is mounted is housed in a package such as a metal case or a resin case, the mounting board is supported by an elastic shock absorbing support. A semiconductor acceleration sensor unit, wherein the package is housed in the package. 2. A first slit for supporting the mounting board on the shock absorbing support, and a second slit in parallel with the first slit in at least one of the vertical direction. The semiconductor acceleration sensor unit according to claim 1. 3. A thin wall portion is formed by denting an outer side surface of the shock absorbing support body, which is located on a side surface of the mounting substrate supported by the first slit. The semiconductor acceleration sensor unit described. 4. The semiconductor acceleration sensor unit according to claim 3, wherein a projection is provided on the outer surface of the thin portion. 5. The shock absorbing material having elasticity is provided on the upper surface of the semiconductor acceleration sensor.
The semiconductor acceleration sensor unit according to 2, 3, or 4. 6. The shock absorbing material having elasticity is provided on at least the upper surface of the mounting substrate.
The semiconductor acceleration sensor unit of 2, 3, 4 or 5. 7. The shock absorbing material having elasticity is provided on the inner surface of the package.
The semiconductor acceleration sensor unit according to 4, 5, or 6. 8. The package is provided with a feedthrough capacitor, and a sensor signal is taken out of the unit from an electrode terminal of the feedthrough capacitor inserted into a through hole provided in the mounting substrate. 4. The semiconductor acceleration sensor unit according to 4, 5, 6 or 7, wherein the electrode terminals and the sensor signal extracting portion on the mounting board are electrically connected by a flexible lead wire inside the unit. Acceleration sensor unit. 9. The package is provided with a feedthrough capacitor, and a sensor signal is taken out of the unit from an electrode terminal of the feedthrough capacitor which is inserted into a through hole provided in the mounting substrate. The semiconductor acceleration sensor unit described in 4, 5, 6 or 7 is characterized in that the electrode terminal and the sensor signal extraction portion on the mounting substrate are electrically connected inside the unit by a metal plate having a spring property. And semiconductor acceleration sensor unit. 10. The package is provided with a feedthrough capacitor, and the sensor signal is taken out of the unit from an electrode terminal of the feedthrough capacitor which is inserted into a through hole provided in the mounting substrate. The semiconductor acceleration sensor unit described in 4, 5, 6 or 7 is characterized in that the electrode terminal and the sensor signal extracting portion on the mounting substrate are electrically connected inside the unit by a coil-shaped conductor. Semiconductor acceleration sensor unit. 11. The inside of the package is substantially filled with a gel-like substance, 1, 2, 3, 4,
The semiconductor acceleration sensor unit according to 5, 6, 7, 8, 9 or 10.