JPH05149967A - Semiconductor acceleration sensor - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention, without using a damping liquid,
An object of the present invention is to provide a semiconductor acceleration sensor capable of buffering an external shock and maintaining normal operation without damaging the semiconductor acceleration sensor. According to the present invention, a circuit board on which a semiconductor acceleration sensor is mounted is set to a length that absorbs vibration and held by a connection terminal itself for connecting to a circuit of the circuit board, and the connection terminal itself receives an impact from the outside. From the outside by adding a vibration absorbing structure to the connection terminal itself, further holding the circuit board by the vibration absorbing member, and loading the gel-like insulating material in addition to the vibration absorbing member into the housing. It absorbs and absorbs the shock of to prevent damage to the semiconductor acceleration sensor.

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 which is formed by etching a semiconductor substrate and is used, for example, for detecting the acceleration of an automobile.

[0002]

2. Description of the Related Art The semiconductor acceleration sensor described above is constructed as shown in FIG. That is, a weight 1 is formed in the center of a substrate made of a semiconductor by etching to simultaneously form a support frame 2 on the periphery, and the support frame 2 and the weight 1 are simultaneously formed.
And 2 are connected by beam portions 3 and 3 at the same side, and a fixed substrate 4 is provided so as to face the weight portion 1 and one side surface of the support frame 2, and the fixed substrate 4 and the weight portion 1 described above A weight gap 1 is formed so as to be movable in the plane direction with respect to the fixed substrate 4, and a small size of about 3 mm square or less is formed.

The semiconductor acceleration sensor 5 having the above structure
Detects the acceleration by detecting the change in the capacitance between the weight portion 1 and the fixed substrate 4 when the weight portion 1 is moved by the acceleration, or the amount of strain of the beam portions 3 and 3. Since the parts 3 and 3 are vulnerable to impact, there is damage to this part, and as one means for solving this, as shown in FIG. 7, the semiconductor acceleration sensor 5 is surrounded by a metal case 6 to protect the inside. A means for filling with a damping liquid 7 such as silicon oil is taken, and the semiconductor acceleration sensor 5 thus formed into a case is mounted on a circuit board 8 on which necessary circuits such as a signal detection circuit and an amplification circuit are mounted. It was

However, as described above, in the case of the semiconductor acceleration sensor 5 in which the damping liquid 7 is loaded inside the case, the flow passage 9 around the weight portion 1 is narrow, and the smaller the size of the flow passage 9, the smaller the flow passage 9 becomes. When the damping liquid 7 becomes narrower and the damping liquid 7 passes through the flow path 9 each time the weight portion 1 moves by detecting the acceleration, the effective viscosity of the damping liquid 7 increases, which adversely affects the frequency response of the semiconductor acceleration sensor 5. In addition, there is a problem in that the viscosity of the damping liquid changes depending on the temperature, and this change also has a problem that the above frequency response is adversely affected. Furthermore, the damping liquid itself is enclosed in a small case. Has a problem of poor workability.

[0005]

SUMMARY OF THE INVENTION The present invention provides a semiconductor acceleration sensor which can buffer a shock from the outside without using a damping liquid and can maintain a normal operation without damaging the sensor. To aim.

[0006]

The present invention (Claim 1)
Is a semiconductor acceleration sensor in which a circuit board on which the semiconductor acceleration sensor is mounted is set to a length that absorbs vibration and is held by a connection terminal itself for connecting to a circuit of the circuit board.

According to the present invention (claim 2), the circuit board on which the semiconductor acceleration sensor is mounted is held by the connection terminal itself which is set to a predetermined length and connected to the circuit of the circuit board, and the intermediate portion of the connection terminal is provided. The semiconductor acceleration sensor is characterized in that a vibration absorbing structure is formed on it.

According to the present invention (claim 3), the circuit board on which the semiconductor acceleration sensor is mounted is held by the elastic vibration absorbing member, and the connection wiring to the circuit board is long enough not to interfere with the vibration absorbing operation of the vibration absorbing member. It is a semiconductor acceleration sensor formed of a flexible lead wire.

The present invention (claim 4) is a semiconductor acceleration sensor in which a circuit board on which a semiconductor acceleration sensor is mounted is held by a vibration absorbing member having elasticity, and a connection wiring to the circuit board is formed by a multi-wire brush. It is characterized by being.

According to the present invention (claim 5), the circuit board on which the semiconductor acceleration sensor is mounted is surrounded by the housing, and the circuit board is held by the elastic vibration absorbing member which is held by the inner wall of the housing and is housed in the housing. It is a semiconductor acceleration sensor filled with a gel-like insulating material.

[0011]

According to the present invention, in claim 1, the connection terminal itself absorbs and cushions an impact from the outside, and in claim 2, in addition to the connection terminal itself, the vibration absorbing structure absorbs and cushions an impact from the outside. In addition, in claims 3 and 4, the vibration absorbing member absorbs and cushions external impacts, and in addition to the vibration absorbing member, the gel insulating material absorbs and cushions external impacts. Damping of the semiconductor acceleration sensor is prevented by the vibration absorption buffer according to the structure of each claim.

[0012]

According to the present invention, since the damping liquid is not used for the vibration absorbing member, a change in the effective viscosity of the damping liquid and a change in the viscosity due to a temperature change do not impair the frequency response, and the vibration is simple. The structure has a vibration absorbing cushioning effect, and accurate acceleration can be detected. Further, since the damping liquid is not enclosed, the workability of production is improved.

Further, by forming the connecting wiring with a flexible lead wire or a multi-wire brush, it is possible to freely connect even a narrow structure portion without impairing the shock absorbing property of the vibration absorbing member, and the degree of freedom in structural designing. Is improved.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows the semiconductor acceleration sensor unit of the first embodiment, and the semiconductor acceleration sensor 10 has the same structure as the conventional sensor 5 shown in FIG.
It is implemented in 1. The first circuit board 11 is formed by printing circuit wirings connected to the electrodes of the semiconductor acceleration sensor 10, and is also mounted with the minimum necessary electronic components. On the other hand, on the second circuit board 12, for example, a housing 14 formed of resin or the like on which electronic components 13 constituting detection circuits such as a constant voltage circuit, an amplifier, a comparison circuit, etc. are mounted.
Is fixed to the bottom of the first circuit board 11 and
Can be connected vertically with a predetermined interval in the vertical direction, that is, by connecting terminals 15 ... Set to a length capable of absorbing vibration, and the first circuit board 11 can absorb vibration. The sensor unit 16 is configured to be held at. Reference numeral 17 in the drawing is a lead wire connected to the outside.

When the semiconductor acceleration sensor 10 is constructed as described above, shocks received from the outside are absorbed and absorbed by the material elasticity of the connection terminal 15 to prevent the semiconductor acceleration sensor 10 from damaging the beam portion (see FIG. 6). Further, since the circuit board is divided into the first and second circuit boards 11 and 12 and arranged in the upper and lower parts, the projected area can be reduced, which is effective for downsizing. ..

FIG. 2 shows a semiconductor acceleration sensor unit according to the second embodiment. The parts having the same functions as those of the above-mentioned first embodiment are designated by the same reference numerals and the detailed description thereof will be omitted. That is, in the second embodiment, the vibration absorbing structure 18 is formed by bending the intermediate portion of the connection terminals 15 ... In a U shape. In addition,
The shape of the vibration absorbing structure 18 may be a dogleg shape, a U shape, or another shape.

With this structure, in addition to the function of absorbing the vibration of the connection terminals 15 ..., which has been described in the first embodiment, the effect of absorbing the shape of the vibration absorbing structure 18 can be obtained, which is effective. Vibration absorption is obtained and damage to the semiconductor acceleration sensor 10 is prevented.

FIG. 3 shows a semiconductor acceleration sensor unit according to the third embodiment. The parts having the same functions as those of the first embodiment described above are designated by the same reference numerals and the detailed description thereof will be omitted. That is, in the second embodiment, the first circuit board 11 is provided with the vibration absorbing member 19 having elasticity such as silicon rubber.
(The upper and lower ends of the vibration absorbing member 19 are adhered to both the circuit boards 11 and 12 by appropriate adhering means).
Flexible lead wires 20 are used as the lead wires for connecting the circuits 1 and 12, and the length of the flexible lead wires 20 is set to the minimum necessary length that does not impede the vibration absorbing and damping function of the vibration absorbing member 19. There is.

With this structure, the vibration-absorbing member 19 can obtain a shock-absorbing cushioning effect against an external impact, and an effective shock-absorbing cushioning can be obtained.
To prevent damage. Even if the vibration absorbing member 19 moves at the same time,
Since the flexible lead wire 20 is longer than its movable amount,
It does not interfere with the buffering effect.

FIG. 4 shows a semiconductor acceleration sensor unit according to the fourth embodiment. The parts having the same functions as those of the first embodiment described above are designated by the same reference numerals and the detailed description thereof will be omitted. That is, in the fourth embodiment, the first circuit board 11 on which the semiconductor acceleration sensor 10 is mounted is sandwiched between the vibration absorbing members 21 and 21 having elasticity, such as silicon rubber, to form the second circuit board 12. Mounted on the upper surface, both circuit boards 11, 1
The lead wire for connecting the circuit of FIG.
The multi-wire brush 22 arranged between them is used so as not to impede the vibration absorbing cushioning action of the vibration absorbing members 21, 21.

With this structure, the vibration absorbing member 21,
21 can obtain a shock absorbing cushioning effect against the impact from the outside, an effective shock absorbing cushioning can be obtained, and the semiconductor acceleration sensor 10 is prevented from being damaged. At the same time, even if the vibration absorbing member 21 moves, the elasticity of the multi-wire brush 22 can maintain the circuit connection, which does not hinder the acceleration detection.

FIG. 5 shows a semiconductor acceleration sensor unit according to the fifth embodiment. The parts having the same functions as those of the first embodiment described above are designated by the same reference numerals and the detailed description thereof will be omitted. That is, in the fifth embodiment, the vibration absorbing member 23 having elasticity such as silicon rubber is attached to the inner wall surface of the housing 14, and the first circuit board 11 on which the semiconductor acceleration sensor 10 is mounted is mounted on the vibration absorbing member 23. It is sandwiched and connected to the second circuit board (not shown) by a lead wire 17 outside the housing 14. The inside of the housing 14 is filled with a gel insulating material 24 such as silicone resin.

With such a structure, the vibration absorbing member 23,
In addition to 23 having a shock absorbing and shock absorbing function against external impact, the gel insulating material 24 also has a shock absorbing and shock absorbing function, and by these functions, effective shock absorbing buffer is obtained and the semiconductor acceleration sensor 10 is damaged. Prevent. The present invention is not limited to the configurations of the various embodiments described above.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of a semiconductor acceleration sensor unit.

FIG. 2 is a sectional view showing a second embodiment of a semiconductor acceleration sensor unit.

FIG. 3 is a sectional view showing a third embodiment of a semiconductor acceleration sensor unit.

FIG. 4 is a sectional view showing a fourth embodiment of a semiconductor acceleration sensor unit.

FIG. 5 is a sectional view showing a fifth embodiment of a semiconductor acceleration sensor unit.

FIG. 6 is a perspective view showing a conventional semiconductor acceleration sensor.

FIG. 7 is a sectional view of a sensor unit equipped with a conventional semiconductor acceleration sensor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Semiconductor acceleration sensor 11 ... 1st circuit board 12 ... 2nd circuit board 13 ... Electronic component 14 ... Housing 15 ... Connection terminal 18 ... Vibration absorbing structure 19,21,23 ... Vibration absorbing member 20 ... Flexible lead wire 22 ... Multi Wire brush 24 ... Gel-like insulating material

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Koichi Hikasa, No. 10 Hanazono Dodo-cho, Ukyo-ku, Kyoto City, Kyoto Prefecture Omron Co., Ltd. (72) Masakazu Shiiki, No. 10 Hanazono Todo-cho, Ukyo-ku, Kyoto Prefecture, Kyoto Co., Ltd. (72) Inventor Katsumi Hosoya, No. 10 Hanazono Dodocho, Ukyo-ku, Kyoto City, Kyoto Prefecture Omron Corporation

Claims (5)

[Claims] 1. A semiconductor acceleration sensor in which a circuit board on which a semiconductor acceleration sensor is mounted is set to a length for absorbing vibration and held by a connection terminal itself for connecting to a circuit of the circuit board. 2. A semiconductor in which a circuit board on which a semiconductor acceleration sensor is mounted is set to a predetermined length and held by a connection terminal itself for connecting to a circuit of the circuit board, and a vibration absorbing structure is formed in an intermediate portion of the connection terminal. Acceleration sensor. 3. A circuit board on which a semiconductor acceleration sensor is mounted is held by a vibration absorbing member having elasticity, and a connecting wire for the circuit board is formed by a flexible lead wire having a length that does not hinder the vibration absorbing operation of the vibration absorbing member. Accelerated semiconductor acceleration sensor. 4. A semiconductor acceleration sensor in which a circuit board on which the semiconductor acceleration sensor is mounted is held by a vibration absorbing member having elasticity, and a connection wiring to the circuit board is formed by a multi-wire brush. 5. A circuit board on which a semiconductor acceleration sensor is mounted is surrounded by a housing, and the circuit board is held by a vibrating member which is held by an inner wall of the housing and has elasticity, and the housing is filled with a gel insulating material. Semiconductor acceleration sensor.