KR100918188B1 - Vibration sensor of independent electric power type and vibration sensor module using the same - Google Patents

Abstract

An independent electric power vibration sensor and a vibration sensor module using the same are provided to improve sensitivity and reliability of the vibration sensor by removing the signal drop due to the formation of the power line. A second vibration plate(11b) is spaced to face a first vibration plate(11a) with a predetermined interval. A piezo element layer generates the piezo electricity according to the mechanical deformation from the outside. A third vibration plate(11c) is spaced to face the second vibration plate with the predetermined interval. A piezo ceramic element layer senses the vibration from the outside and outputs the vibration sensing signal. The piezo element layer includes the piezo element powder. The piezoelectric ceramic element layer includes the piezoelectric ceramic element powder.

Description

Self-Generated Vibration Sensor and Vibration Sensor Module Using Them {VIBRATION SENSOR OF INDEPENDENT ELECTRIC POWER TYPE AND VIBRATION SENSOR MODULE USING THE SAME}

The present invention relates to a self-powered vibration sensor and a vibration sensor module using the same, and more particularly, by using the power generated by the vibration sensor itself without a separate power supply, to eliminate the signal drop due to the formation of the power line The present invention relates to a self-powered vibration sensor and a vibration sensor module using the same that improve the sensitivity and reliability of the vibration sensor.

The vibration sensor is a sensor for detecting an external vibration. Such vibration sensors can be largely classified into a method using a semiconductor characteristic and a method using a mechanical resonance mode.

The method using the semiconductor characteristics is a method of making a fine structure using semiconductor technology and recognizing vibration or acceleration due to a change in resistance value or current value that appears as the structure itself is inclined along the acceleration direction. It is widely used because it easily detects vibration and acceleration in the X, Y, and Z directions.

On the other hand, the vibration sensor using the mechanical resonance mode measures the change in the magnetic field, the position of the ball, or the tension acting on the spring by the force generated by the acceleration of the object connected to the spring inside the vibration or This is a way of recognizing acceleration changes. Vibration sensors using a mechanical resonance mode can detect a wide bandwidth signal, but it is difficult to construct an internal structure, so it is widely used for special industrial or military use.

Piezoelectric ceramic elements are a material widely used for vibration sensors utilizing the above-described semiconductor characteristics. Piezoelectric ceramic devices have a peculiar characteristic called piezoelectric phenomenon, which is an electric polarization (electric field or voltage) induced when mechanical deformation is applied from the outside. In addition, mechanical deformation occurs when a piezoelectric electric field is applied to the piezoelectric ceramic element. As described above, the piezoelectric phenomenon generated in the piezoelectric ceramic element may be detected by an external force such as vibration applied from the outside, and thus it may be used as a vibration sensor.

1 is a diagram showing a circuit configuration provided with a vibration sensor using a conventional piezoelectric ceramic element. Referring to FIG. 1, in order for a vibration sensor using a piezoelectric ceramic element to function as a vibrator for detecting vibration, power must be supplied to the vibration sensor through a resistor R1.

However, when the vibration is generated by the vibration from the outside, the vibration sensor reacts to generate a signal, that is, a change in voltage. Since a reverse drop occurs through the resistor R1 for power supply, signal loss occurs. do. This may act as a cause of impairing the sensitivity or reliability of the vibration sensor.

In addition, since the signal output from the vibration sensor is connected to the base of TR1, the signal is amplified through the base, but the drop of the signal also occurs, thereby acting as a cause of impairing the sensitivity or reliability of the vibration sensor.

Accordingly, the present invention has been made to solve the above problems, by using the power generated by the vibration sensor itself without a separate power supply, by removing the signal drop phenomenon due to the formation of the power line sensitivity and sensitivity of the vibration sensor The object of the present invention is to provide a self-generated vibration sensor with improved reliability. In addition, an object of the present invention is to provide a self-developed vibration sensor capable of increasing the sensitivity of the vibration sensor to detect even minute vibrations.

Further, the object of the present invention is to provide a vibration sensor module that can be installed in an installation location that can be affected by water, such as underwater or underground, and can detect even minute vibrations.

According to the present invention, the object and the first diaphragm; A second diaphragm spaced apart from the first diaphragm by a predetermined interval; A piezoelectric element layer interposed between the first diaphragm and the second diaphragm to generate piezoelectricity according to mechanical deformation from the outside; A third diaphragm spaced apart from the second diaphragm by a predetermined interval; And a piezoelectric ceramic element layer which is maintained in an ecological state charged by the piezoelectric electricity generated in the piezoelectric element layer and detects vibration from the outside and outputs a vibration detection signal. It is achieved by a self-generating vibration sensor characterized in that.

Here, the piezoelectric element layer is provided including a piezoelectric element in powder form; The piezoelectric ceramic element layer is provided including a piezoelectric ceramic element in powder form; The display device may further include a first sealing member sealing the edge region between the first diaphragm and the second diaphragm, and a second sealing member sealing the edge region between the second diaphragm and the second diaphragm.

The piezoelectric ceramic device may be any one or a mixture of barium titanate, lead zirconate-titanate, lead titanate, and sodium-potassium niobate. Can be arranged.

On the other hand, according to another embodiment of the present invention, the module body is opened upwardly formed receiving space therein; A body cover for closing an upper portion of the module body; A piezoelectric vibration sensor mounted on a bottom surface of the module body and accommodated in the accommodation space; A signal processing module accommodated in the accommodation space of the module main body so as to be disposed above the vibration sensor and processing the vibration detection signal from the vibration sensor; At least one coupling hole formed on an outer circumferential surface of the module body; One side is inserted into the coupling hole is coupled to the other side is connected to a structure adjacent to the vibration sensor module is installed in the vibration sensor module comprising a vibration transmission cable for transmitting vibration from the outside to the module body Can also be achieved.

Here, the thread is formed on the inner wall surface of the coupling hole is provided to be screwed with one side of the vibration transmission cable; An at least one region between the coupling hole and the vibration transmission cable may be provided with a sealing member made of an elastic material.

The vibration sensor is provided with the self-generating vibration sensor; The first diaphragm of the self-generating vibration sensor may be attached to the bottom surface of the module body.

In addition, a ring insertion groove is formed in the upper surface of the module body along the circumferential direction; It may further include an O-ring of an elastic material inserted into the ring insertion groove to be in close contact with the lower surface of the body cover when the body cover closes the module body.

According to the present invention, there is provided a self-powered vibration sensor that improves the sensitivity and reliability of the vibration sensor by generating and using power from the vibration sensor itself without supplying power, thereby eliminating signal drop due to the formation of a power line. .

In addition, by increasing the sensitivity of the vibration sensor is provided a self-developed vibration sensor that can detect even minute vibration.

In addition, the vibration sensor module can be installed in the installation location that may be affected by moisture, such as underwater or underground, and can detect even minute vibrations.

Hereinafter, with reference to the drawings will be described the present invention in more detail.

As shown in FIGS. 1 and 2, the self-powered vibration sensor 10 according to the present invention includes a first diaphragm 11a, a second diaphragm 11b, a third diaphragm 11c, and a piezoelectric element layer ( 12) and a piezoelectric ceramic element layer 13.

The first diaphragm 11a and the second diaphragm 11b are spaced apart from each other by a predetermined interval. The second diaphragm 11b and the third diaphragm 11c are also spaced apart from each other by a predetermined interval. Here, the first diaphragm 11a, the second diaphragm 11b, and the third diaphragm 11c according to the present invention may be made of a conductive metal material, and in the present invention, an example is provided of silver or aluminum.

The piezoelectric element layer 12 is interposed between the first diaphragm 11a and the second diaphragm 11b. Here, the piezoelectric element layer 12 is provided with a piezoelectric element which generates piezoelectricity in accordance with mechanical deformation from the outside, and in the present invention, vibration.

Here, the piezoelectric element has a property that the electric polarization of the crystal changes when a strain from the outside is applied to the internal crystal, and generates piezoelectric electricity according to the electric polarization.

The piezoelectric ceramic element layer 13 is interposed between the first diaphragm 11a and the second diaphragm 11b. In addition, the piezoelectric ceramic element layer 13 is maintained in a charged state by the piezoelectric dryer generated in the piezoelectric element layer 12, and outputs a vibration detection signal when vibration from the outside is detected.

More specifically, the piezoelectric ceramic element layer 13 functions as an electrical dielectric, and is provided as a piezoelectric ceramic element in the present invention. That is, the piezoelectric ceramic element layer 13 made of a piezoelectric ceramic element, which is an electrical dielectric, is positioned between the second diaphragm 11b and the second diaphragm 11b of a metal material to have a function of a capacitor.

Accordingly, piezoelectric power generated in the piezoelectric element layer 12 is applied to the piezoelectric ceramic element layer 13 according to the vibration from the outside, and according to the polarization phenomenon generated in the piezoelectric ceramic elements constituting the piezoelectric ceramic element layer 13. The piezoelectric ceramic element layer 13 is filled.

In the state in which the piezoelectric ceramic element layer 13 is charged through the above process, when vibration occurs from the outside, the piezoelectric ceramic element layer 13 including the second diaphragm 11b and the third diaphragm 11c vibrate. The vibration can be detected by receiving a change in capacitance caused by vibration and a change in voltage generated by the change in capacitance as a vibration sensing signal.

Here, the piezoelectric ceramic device according to the present invention is any one or two of barium titanate, lead zirconate-titanate, lead titanate, and sodium-potassium niobate. It can be provided with a mixture of the above.

Through the configuration as described above, the piezoelectric ceramic element layer 13 is charged using piezoelectric electricity generated according to the vibration of the piezoelectric element layer 12 so that the piezoelectric ceramic element layer 13 may operate as the vibration sensor 10. By using it as a necessary power source, it is possible to operate as the vibration sensor 10 without a separate power supply. Therefore, the drop phenomenon of the vibration monitoring signal generated from the power line for supplying power in the conventional vibration sensor 10 is removed, thereby improving the sensitivity and reliability as the vibration sensor 10.

In addition, when the piezoelectric ceramic element layer 13 vibrates from the outside, a change in capacitance and a change in voltage according to the same occur at the same time, and the change is output as a vibration detection signal, so that fine vibration can be detected. The effect of improving sensitivity is provided.

4 is a diagram illustrating a circuit configuration for obtaining a vibration monitoring signal from the self-generating vibration sensor 10 according to the present invention. As shown in Figure 4, it can be seen that the power line for supplying power for the operation of the self-generating vibration sensor 10 according to the present invention is not connected.

In addition, the vibration monitoring signal output from the self-powered vibration sensor 10 according to the present invention is connected to the OP AMP 30 through the capacitor (C1) is generated as conventionally connected through the transistor (T1 of FIG. 1) The drop phenomenon can be eliminated.

Here, reference numeral 50 of FIG. 4 denotes a signal processor for outputting a final signal using the vibration detection signal amplified by the OA AMP 30.

On the other hand, the piezoelectric element layer 12 of the self-powered vibration sensor 10 according to the present invention is provided with a piezoelectric element of the powder form, the piezoelectric ceramic element layer 13 is an example that the piezoelectric ceramic element of the powder form is provided. do.

As shown in FIGS. 2 and 3, the piezoelectric element in powder form is prevented from escaping from outside between the first diaphragm 11a and the second diaphragm 11b. The first sealing member 14 for sealing the edge region between the two diaphragms 11b is provided. Similarly, the edge region between the second diaphragm 11b and the third diaphragm 11c is prevented so that the piezoelectric ceramic element in powder form is prevented from escaping from outside between the second diaphragm 11b and the third diaphragm 11c. A second sealing member 14 for sealing is provided.

Here, the first sealing member 14 and the second sealing member 14 according to the present invention, the vibration from the outside is the first diaphragm 11a, the second diaphragm 11b, the third diaphragm 11c, the piezo element Preferably, the layer 12 and the piezoelectric ceramic element layer 13 are made of a material having elasticity, such as a silicon material.

Hereinafter, the vibration sensor module 1 according to the present invention will be described in detail with reference to FIGS. 5 and 6.

As shown in FIGS. 5 and 6, the vibration sensor module 1 according to the present invention includes a module main body 80, a main body cover 70, a vibration sensor 10, a signal processing module 10a, and a module main body. At least one coupling hole 81 and the vibration transmission cable 90 formed in the (80).

The module body 80 has an upwardly open shape in which a receiving space 80a is formed. In the present invention, the module main body 80 has a flat cylindrical shape as an example, but the shape is not limited thereto.

The body cover 70 closes the upper portion of the module body 80. Here, the upper surface of the module main body 80 is formed with a plurality of threaded holes 80c with threads formed therein along the circumferential direction, and the body cover 70 corresponds to the screw holes 80c of the module main body 80. A plurality of through holes 70c formed through the holes are formed, and the screw holes 80c are screwed into the screws or bolts 91 passing through the through holes 70c, respectively, so that the main body cover 70 is formed by the module main body ( For example, closing 80).

Here, the upper part of the module main body 80 is formed to be stepped, as shown in FIGS. 5 and 6, so that the main body cover 70 is inserted into the stepped area when the upper part of the module main body 80 is closed. The upper part of the vibration sensor module 1 according to the present invention becomes a flat shape.

In addition, as shown in FIGS. 5 and 6, a ring insertion groove 80b may be formed along the circumferential direction on the upper surface of the module main body 80. In addition, an O-ring 85 made of an elastic material is inserted into the ring insertion groove 80b. Accordingly, when the main body cover 70 closes the upper portion of the module main body 80, the lower surface of the main body cover 70 comes into close contact with the O-ring 85 made of an elastic material, so that the inner receiving space 80a of the module main body 80 is closed. ) Can be sealed.

On the other hand, the vibration sensor 10 is accommodated in the receiving space (80a) formed in the module main body 80, in the present invention is an example that the vibration sensor 10 is seated on the bottom surface of the module main body (80). Accordingly, when the vibration from the outside is transmitted to the module main body 80, the vibration can be transmitted from the module main body 80 to the vibration sensor 10 attached to the bottom surface.

Here, the vibration sensor 10 used in the vibration sensor module 1 according to the present invention is a piezoelectric vibration sensor 10, in the present invention is applied to the above-described self-generated vibration sensor 10 as an example do. At this time, the first diaphragm 11a of the self-generating vibration sensor 10 is attached to the bottom surface of the module main body 80.

The signal processing module 10a is accommodated in the accommodation space 80a of the module main body 80 so as to be disposed above the vibration sensor 10. In addition, the signal processing module 10a processes the vibration detection signal transmitted from the vibration sensor 10 and outputs it to the outside of the vibration sensor module 1. Here, for example, the signal processing module 10a according to the present invention is provided in a PCB form.

On the other hand, the coupling hole 81 is formed on the outer peripheral surface of the module main body 80, in the present invention, as shown in Figure 5, three coupling holes 81 are formed in the module main body 80 as an example have.

One side of the vibration transmission cable 90 is inserted into the coupling hole (81). Here, the inner wall surface of the coupling hole 81, as shown in Figure 6, the thread is formed on the inner wall surface is an example that is screwed through the screw thread formed on one side of the vibration transmission cable (90).

In addition, the other side of the vibration transmission cable 90 is connected to a structure adjacent to the vibration sensor module 1 is installed according to the present invention. Here, the vibration transmission cable 90 is installed to be maintained in a tensioned state in both end directions.

According to the configuration as described above, when the vibration is generated from the outside, the vibration flowing into the module main body 80, the vibration sensor 10 is accommodated, and the vibration flowing into the vibration transmission cable 90 to the vibration transmission cable 90 By being transferred to the module main body 80, the amount of vibration transmitted to the vibration sensor 10 is increased to improve sensitivity to vibrations that can detect even minute vibrations.

Here, in at least one region between the coupling hole 81 and the vibration transmission cable 90 of the module body 80, as shown in Figure 6, an elastic member 82 of an elastic material may be interposed. Referring to FIG. 6, a vibration transmitting cable formed to have a radially outer region of the coupling hole 81 stepped therein and a cylindrical elastic member 82 inserted therein to pass through the elastic member 82 ( 90) is coupled through a thread formed therein. As a result, the vibration transmission cable 90 and the elastic member 82 are hermetically contacted by the elastic force of the elastic member 82, thereby preventing moisture or air from flowing into the coupling hole 81.

In addition, a power cable through hole 81a may be formed on an outer circumferential surface of the module main body 80. Then, the power cable 82 passes through the power cable through hole 81a from the outside of the module main body 80 and is connected to the signal processing module 10a housed in the module main body 80, thereby preventing the vibration sensor 10. The vibration detection signal outputted and subjected to signal processing such as amplification by the signal processing module 10 may be transmitted to the outside of the vibration sensor module 1.

Meanwhile, the connection portion between the module main body 80 and the main body cover 70 of the vibration sensor module 1 according to the present invention, the through hole 70c and the coupling hole 81 of the main body cover 70 are made of a silicon material. It can be sealed using waterproof material. In addition, the vibration transmission cable 90 may be configured of a metal inner core member and a waterproof cover surrounding the inner core member for waterproofing the inner core member.

Thus, by waterproofing the exterior of the vibration sensor module 1, it is possible to install the vibration sensor module 1 in a place that can be affected by moisture, such as underwater or underground. In addition, the vibration generated from the outside is transmitted to the vibration sensor 10 accommodated in the module body 80 through the vibration transmission cable 90 and the module body 80, the existing vibration sensor 10 due to the waterproof treatment It is possible to eliminate the phenomenon that the sensitivity to vibration is impaired.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

1 is a view showing a circuit configuration provided with a vibration sensor using a conventional piezoelectric ceramic element,

2 is a perspective view of a self-generating vibration sensor according to the present invention,

3 is a cross-sectional view taken along line III-III of FIG. 2,

4 is a diagram illustrating a circuit configuration in which a self-generating vibration sensor is installed according to the present invention.

5 is an exploded perspective view of a vibration sensor module according to the present invention;

6 is a cross-sectional view taken along line VI-VI of FIG. 5.

Claims (7)

In the self-generating vibration sensor, A first diaphragm; A second diaphragm spaced apart from the first diaphragm by a predetermined interval; A piezoelectric element layer interposed between the first diaphragm and the second diaphragm to generate piezoelectricity according to mechanical deformation from the outside; A third diaphragm spaced apart from the second diaphragm by a predetermined interval; And a piezoelectric ceramic element layer which is maintained in an ecological state charged by the piezoelectric power generated in the piezoelectric element layer and detects vibration from the outside and outputs a vibration detection signal. The method of claim 1, The piezoelectric element layer includes a piezoelectric element in powder form; The piezoelectric ceramic element layer is provided including a piezoelectric ceramic element in powder form; And a first sealing member sealing the edge region between the first diaphragm and the second diaphragm, and a second sealing member sealing the edge region between the second diaphragm and the second diaphragm. Self-generated vibration sensor. The method of claim 2, The piezoelectric ceramic device is made of any one or a mixture of barium titanate, lead zirconate-titanate, lead titanate, and sodium-potassium niobate. Self-powered vibration sensor, characterized in that. In the vibration sensor module, An upwardly open module body having an accommodating space therein; A body cover for closing an upper portion of the module body; A piezoelectric vibration sensor mounted on a bottom surface of the module body and accommodated in the accommodation space; A signal processing module accommodated in the accommodation space of the module main body so as to be disposed above the vibration sensor and processing the vibration detection signal from the vibration sensor; At least one coupling hole formed on an outer circumferential surface of the module body; One side is inserted into the coupling hole is coupled to the other side is connected to a structure adjacent to the vibration sensor module is installed, the vibration sensor module comprising a vibration transmission cable for transmitting vibration from the outside to the module body. The method of claim 4, wherein A screw thread is formed on an inner wall surface of the coupling hole to be screwed to one side of the vibration transmission cable; And at least one region between the coupling hole and the vibration transmission cable is provided with a sealing member made of an elastic material. The method of claim 5, The vibration sensor is provided with a self-powered vibration sensor according to any one of claims 1 to 3; And the first diaphragm of the self-generating vibration sensor is attached to a bottom surface of the module body. The method of claim 6, A ring insertion groove is formed in an upper surface of the module body along a circumferential direction; And an o-ring made of an elastic material inserted into the ring insertion groove to be in close contact with the lower surface of the main body cover when the main body cover closes the module main body.

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