JP2861694B2 - Servo type vibration sensor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a servo vibration sensor for detecting vibration displacement.

[0002]

2. Description of the Related Art A conventional example of a servo type vibration sensor is shown in FIG. In the figure, coils 7a and 7b for holding the weight 5 at a neutral position are exposed and arranged on the upper and lower sides of the center of the weight 5 as a vibrator. Weight 5
The electrodes 8a and 8b are provided in the vicinity of one end, and the displacement of the weight 5 is detected as a change in the capacitance between the electrodes 8a and 8b. The displacement signals detected by the electrodes 8a and 8b are applied to a servo amplifier 18,
A control output is applied to the coils 7a and 7b from 18 so that the weight 5 moves in the direction opposite to the displacement direction, and the servo drive is performed so that the weight 5 always keeps the neutral position. The current applied to the coils 7a and 7b for servo driving is extracted as a vibration displacement detection signal.

[0003]

However, in the above conventional example, the weight 5 and the coil 7 which are separate bodies are different from each other.
A step of assembling the weights a and 7b is required, and the operation of holding the weight 5 at the neutral position by the coils 7a and 7b is complicated and requires skill. Therefore, the production cost is increased, and the yield is further reduced.

Further, in order to increase the detection sensitivity and the driving force of the servo, it is necessary to use a large weight 5 and coils 7a and 7b, which causes a problem that the whole sensor becomes large.

Further, since the coils 7a and 7b are disposed so as to be exposed from the weight 5, there is a problem that the coils 7a and 7b are disconnected.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and it is an object of the present invention to provide a small-sized and high-precision servo which can be easily manufactured without skill, without fear of coil disconnection. An object of the present invention is to provide a shape vibration sensor.

[0007]

The present invention is configured as follows to achieve the above object. That is, the servo-type vibration sensor of the present invention comprises a plurality of substrates on each of which a coil pattern is formed, which is integrated into a vibrator to form a vibrator, a vibration detecting unit for detecting vibration displacement of the vibrator, and a vibrator for the vibrator. And a servo means for returning a vibrator to a neutral position by applying a force in a direction opposite to the displacement direction of the vibrator.

[0008]

When the vibrator is displaced by vibration, the vibration displacement is detected by the vibration detecting section and output as a vibration displacement signal or an acceleration signal. This signal is converted to a servo output current by servo means,
By applying the servo output current to the coil pattern of the vibrator, the vibrator returns to the neutral position.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a configuration diagram of one embodiment of a servo vibration sensor according to the present invention.

In FIG. 1, a semiconductor substrate 12 such as silicon
The concave portions 13a, 13b, 13c and 13d are formed thereon by a semiconductor fine processing technique such as a photolithography process, and a magnetic material is deposited on the magnetic yoke forming portion on the surface to form magnetic yokes 14a, 14b, 14c and 14d. Are formed. On the inner surfaces of the magnetic yokes 14a, 14d, permanent magnets 6a, 6
b is provided. Electrodes 8a and 8b are formed on the left and right side surfaces of the recess 13c.

On the other hand, holes 19a and 19b are opened in the plurality of substrates 9 constituting the vibrator 2, and both holes 19a and 19b are opened.
A coil pattern 1 is formed so as to surround 19b.
The vibrator 2 is formed by integrally laminating a plurality of the substrates 9. The coil patterns 1 on each substrate 9 are electrically connected by through-hole means or the like. The vibrator 2 is fitted in the magnetic legs of the magnetic yokes 14b and 14c using the holes 19 in a loosely inserted state, and is disposed to be vertically movable. Flexible springs 16a and 16b supporting one end of the vibrator 2 are magnetic yokes 14a.
And connected to the servo circuit 4 through the spring 16
Reference numerals a and 16b also function as a support for the vibrator 2 and as a wiring member for the coil pattern 1. Vibrator 2
A protrusion 15 made of plastic or metal protrudes from the lower center of the substrate. When the vibrator 2 is displaced by vibration, the protrusion 15 is vertically displaced between the electrodes 8a and 8b. This projection 15
The electrodes 8a and 8b constitute the vibration detecting section 3, and the electrodes 8a and 8b are connected to the detecting circuit 17. Electrode 8
a and 8b are displacements of the vibrator 2 due to vibration, that is, protrusions.
The displacement of 15 is detected as a change in capacitance between the electrodes 8a and 8b, and the detection circuit 17 processes a signal from this electrode and outputs it as a displacement signal or an acceleration signal.

The servo circuit 4 functioning as a servo means receives a signal from the detection circuit 17 and converts the signal into a servo output current.
In addition, the displaced vibrator 2 is returned to the neutral position.

The present invention is configured as described above. When the vibrator 2 vibrates and is displaced from the neutral position, the projection 15 also moves, so that the capacitance between the electrodes 8a and 8b changes. This change in capacitance is detected as a vibration displacement amount by the electrodes 8a and 8b, and a vibration displacement signal or an acceleration signal is detected by a detection circuit.
Output from 17. This signal is applied to the servo circuit 4, and the servo circuit 4 applies a servo output current to the coil pattern 1 of the vibrator 2, and the coil pattern 1 receives the servo output current and a magnetic field from the permanent magnets 6a and 6b. It receives electromagnetic force according to Fleming's left hand rule. The vibrator 2 returns to the neutral position by this electromagnetic force.

In the servo vibration sensor according to the present embodiment, the vibrator 2 is formed by laminating and integrating a plurality of substrates 9 on which the coil patterns 1 are formed. The size is drastically reduced as compared with the case of assembling the weight 7b and the weight 5 as a vibrator. Also, as in the conventional case, the weight 5 and the coils 7a, 7b
Since the structure of the portion is not complicated, it can be easily manufactured without requiring skill. Therefore, the yield of the servo type vibration sensor of the present invention is improved, and the cost is reduced.

Further, since the vibrator 2 is reduced in size and weight, it can be moved easily and easily, and vibration in a high frequency range can be easily detected. Becomes

Further, a silicon substrate 12 on which the vibrator 2 is disposed
Since the concave portion 13 of can be formed by semiconductor fine processing technology,
The configuration of the entire sensor becomes smaller and more accurate.

Further, in this embodiment, since the laminated coil pattern-formed on the substrate 9 is built in the vibrator, there is no fear of coil disconnection or the like.

The present invention is not limited to the above embodiment, but can take various embodiments. For example, in the above embodiment, a silicon substrate is used as the substrate 12, but a semiconductor substrate such as germanium or gallium arsenide may be used. Further, instead of a semiconductor substrate, a substrate made of plastic, metal, or the like may be used. In this case, the magnetic yoke 14 is formed by disposing a magnetic body such as an iron core.

Further, in the present embodiment, the detection circuit 17 and the servo circuit 4 are formed on the substrate 12, but they may be provided at positions away from the substrate 12.

Further, in this embodiment, the projection 15 is
Is formed at the lower center of the vibrator 2, but may be formed at the lower right end side of the vibrator 2 as long as the vibration displacement of the vibrator 2 can be detected. In this case, the positions of the electrodes 8a and 8b constituting the vibration detecting section 3 together with the protrusions 15 also change to the lower side of the protrusions 15.

Further, in this embodiment, the vibration displacement is
Although it is extracted as a change in capacitance between a and 8b, it may be extracted as other electrical and physical quantities.
It may be taken out as a change in inductance.

Further, in this embodiment, the vibration displacement signal and the acceleration signal are taken out from the detection circuit 17, but they may be taken out from the servo circuit 4 as in the conventional example.

Further, in this embodiment, the vibrator 2 is
The springs 16a and 16b can be removed, but in this case, a lead wire for connecting the coil pattern 1 and the servo circuit 4 is separately provided.

[0024]

According to the servo type vibration sensor of the present invention,
Since the vibrator is formed by laminating and integrating a plurality of substrates on which a coil pattern is formed, it is much smaller than a conventional servo-type vibration sensor that is manufactured by assembling a coil and a weight as a vibrator as in the past. You.

Further, in the present invention, since the vibrator and the coil are integrated, there is no need for a complicated operation of assembling the vibrator and the coil with the utmost care, unlike the prior art. Can be easily manufactured. Therefore, the yield is improved and the cost is reduced.

Further, the vibrator is reduced in size and weight, so that the vibrator can be moved easily and easily, and a vibration in a high frequency range can be detected.

Further, in the present invention, since the laminated coil pattern-formed on the substrate is incorporated in the vibrator, there is no fear of disconnection of the coil.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of a servo vibration sensor according to the present invention.

FIG. 2 is a configuration diagram showing a conventional example of a servo vibration sensor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Coil pattern 2 Oscillator 3 Vibration detector 4 Servo circuit (servo means)

Claims (1)

(57) [Claims] An oscillator is formed by laminating a plurality of substrates on each of which a coil pattern is formed to form a vibrator, and a vibration detection unit for detecting a vibration displacement of the vibrator, and a direction opposite to a direction of displacement of the vibrator with respect to the vibrator. And a servo means for applying a force to the actuator to return the vibrator to a neutral position.