阅读说明：本技术 一种高灵敏度自供电加速度传感器及其制备方法 (high-sensitivity self-powered acceleration sensor and preparation method thereof ) 是由 刘超然 王益哨 李耀 董林玺 王高峰 于 2019-09-25 设计创作，主要内容包括：一种高灵敏度自供电加速度传感器,包括绝缘外壳和设置于绝缘外壳内的传感系统,传感系统包括第一电极层、第二电极层、第一摩擦层、第二摩擦层；的第一电极层附着在第一摩擦层的下表面,第一电极层的下表面设有第一电极引线点及由第一电极引线点向外引出的第一导线；第二电极层附着在第二摩擦层的上表面,第二电极层的上表面设有第二电极引线点及由第二电极引线点向外引出的第二导线；第二电极层的上表面连接有绝缘层,绝缘层的上方设置有质量块；第一摩擦层和第二摩擦层均呈拱状且方向相反,第一摩擦层上附着有正电序列摩擦层,第二摩擦层与正电序列摩擦层的电序列相反并在质量块的带动下可与正电序列摩擦层接触分离。(A high-sensitivity self-powered acceleration sensor comprises an insulating shell and a sensing system arranged in the insulating shell, wherein the sensing system comprises a first electrode layer, a second electrode layer, a first friction layer and a second friction layer; the first electrode layer is attached to the lower surface of the first friction layer, and a first electrode lead point and a first lead led out from the first electrode lead point are arranged on the lower surface of the first electrode layer; the second electrode layer is attached to the upper surface of the second friction layer, and a second electrode lead point and a second lead led out from the second electrode lead point are arranged on the upper surface of the second electrode layer; the upper surface of the second electrode layer is connected with an insulating layer, and a mass block is arranged above the insulating layer; the first friction layer and the second friction layer are arched and opposite in direction, the first friction layer is attached with a positive electric sequence friction layer, and the second friction layer is opposite to the electric sequence of the positive electric sequence friction layer and can be in contact with and separated from the positive electric sequence friction layer under the driving of the mass block.)

1. a high sensitivity self-powered acceleration sensor characterized in that: the sensor comprises an insulating shell and a sensing system arranged in the insulating shell, wherein the sensing system comprises a first electrode layer, a second electrode layer, a first friction layer and a second friction layer;

The first electrode layer is attached to the lower surface of the first friction layer, and a first electrode lead point and a first lead led out from the first electrode lead point are arranged on the lower surface of the first electrode layer; the second electrode layer is attached to the upper surface of the second friction layer, and a second electrode lead point and a second lead led out from the second electrode lead point are arranged on the upper surface of the second electrode layer; the upper surface of the second electrode layer is connected with an insulating layer, and a mass block is arranged above the insulating layer;

the first friction layer and the second friction layer are arched and opposite in direction, the first friction layer is attached with a positive electric sequence friction layer, and the second friction layer is opposite to an electric sequence of the positive electric sequence friction layer and can be in contact with and separated from the positive electric sequence friction layer under the driving of the mass block.

2. A high sensitivity self-powered acceleration sensor according to claim 1, characterized in that: the first friction layer and the second friction layer are connected by a strong adhesive tape to form an arch.

3. A high sensitivity self-powered acceleration sensor according to claim 1, characterized in that: the first friction layer and the second friction layer are made of insulating flexible films.

4. A high sensitivity self-powered acceleration sensor according to claim 3, characterized in that: the insulating flexible film is made of polyethylene terephthalate, polyvinyl chloride or polyethylene.

5. A high sensitivity self-powered acceleration sensor according to claim 1, characterized in that: the positive electric sequence friction layer is made of polyformaldehyde, ethyl cellulose, polyamide, melamine or fibroin.

6. A high sensitivity self-powered acceleration sensor according to claim 5 characterized in that: the positively charged serial tribolayer is sprayed onto the first tribolayer by a spray coating technique.

7. a high sensitivity self-powered acceleration sensor according to any of the claims 1-6 characterized in that: and through holes are formed in the two sides of the insulating shell, and the first lead and the second lead penetrate out of the corresponding through holes respectively to be connected with an external circuit.

8. a high sensitivity self-powered acceleration sensor according to claim 1, characterized in that:

the high-sensitivity self-powered acceleration sensor has a brand-new voltage-charge-acceleration (V-Q-a) theoretical model, and the model expression of the high-sensitivity self-powered acceleration sensor is as follows:

Where v (t) is an output voltage between the first electrode layer and the second electrode layer at a certain time t, a is an acceleration acting on the sensor, t is a time of movement of the friction layer, R is an external resistor, Q is a transferred charge amount, S is an area of the friction layer, ∈ 0 is a vacuum dielectric constant, σ is a surface charge density of the friction layer, d0 ═ d1/∈ 1+ d2/∈ 2 is an equivalent thickness of the friction layer, d1 is thicknesses of the first friction layer and the second friction layer, ∈ 1 is a dielectric constant of the first friction layer and the second friction layer, d2 is a thickness of the positive electric series friction layer, and ∈ 2 is a dielectric constant of the positive electric series friction layer.

9. A method for manufacturing a highly sensitive self-powered acceleration sensor according to claim 1, characterized in that: the method comprises the following steps:

Step a), selecting a cuboid insulating shell, and punching a round hole with the diameter of 1-10 mm on the left side and the right side respectively;

B), selecting two insulating flexible films with the same area and attached with conductive layers, and uniformly spraying a positive electric sequence friction layer material solution on the surface of one side of one insulating flexible film without the conductive layer by using a spray gun filled with the positive electric sequence friction layer material solution;

Step c), fixing electrode lead points on the surfaces of the first and second film conductive layers, and connecting wires with the electrode lead points;

Step d), two side edges of the two films are mutually contacted, and the conductive layers face outwards to form an arch shape and are mutually connected through a strong adhesive tape;

Step e), connecting the insulating layer with the second electrode layer by using a strong adhesive tape, and fixing the mass block above the insulating layer to form an internal sensing system; and encapsulating the internal sensing system in an insulating shell to form the high-sensitivity self-powered acceleration sensor.

10. A method for manufacturing a highly sensitive self-powered acceleration sensor according to claim 9, characterized in that: the spraying process in step b): spraying is carried out in a high-temperature environment of 80-200 ℃, and after 3-10 cycles, the spraying duration is 5-15 s in each cycle, and the time interval of each cycle is 10-20 min.

Technical Field

the invention relates to the technical field of self-powered acceleration sensors, in particular to a high-sensitivity self-powered acceleration sensor and a preparation method thereof.

background

The acceleration sensor is a device for measuring acceleration, and plays an important role in the fields of satellites, biomedical equipment, large mechanical structure testing, safety air bags, earthquake monitoring and the like. The acceleration sensors can be classified into different types according to different principles, and common sensors include a capacitive acceleration sensor, a piezoresistive acceleration sensor, a piezoelectric acceleration sensor and the like. The capacitive acceleration sensor and the piezoresistive acceleration sensor can normally work only by external power supply, and the application range of the capacitive acceleration sensor and the piezoresistive acceleration sensor is greatly reduced. Although the piezoelectric sensor can realize self power supply, the output electric signal is very small and is easily influenced by environmental noise. Based on the above problems, self-powered acceleration sensors based on the triboelectric effect have been widely studied. Practice proves that the following problems are generally existed in the existing self-powered acceleration sensor based on the friction power generation effect due to the defects of the structure and the existing process: firstly, the existing self-powered acceleration sensor based on the friction power generation effect has low sensitivity and low output power; secondly, the existing self-powered acceleration sensor based on the friction power generation effect is difficult to manufacture and cannot be produced in a large scale; thirdly, the existing self-powered acceleration sensor based on the friction power generation effect generally adopts a spring structure, so that the cost is increased, and the occupied space is also increased.

Disclosure of Invention

The invention provides a high-sensitivity self-powered acceleration sensor which is high in sensitivity, high in power density, strong in impact resistance, wearable, high in stability, good in stability and consistency.

the invention also provides a preparation method of the high-sensitivity self-powered acceleration sensor, which has the advantages of simple device manufacturing process, low cost and capability of realizing large-scale production and self-powered characteristics.

The technical scheme adopted by the invention is as follows:

A high sensitivity self-powered acceleration sensor characterized in that: the sensor comprises an insulating shell and a sensing system arranged in the insulating shell, wherein the sensing system comprises a first electrode layer, a second electrode layer, a first friction layer and a second friction layer;

The first electrode layer is attached to the lower surface of the first friction layer, and a first electrode lead point and a first lead led out from the first electrode lead point are arranged on the lower surface of the first electrode layer; the second electrode layer is attached to the upper surface of the second friction layer, and a second electrode lead point and a second lead led out from the second electrode lead point are arranged on the upper surface of the second electrode layer; the upper surface of the second electrode layer is connected with an insulating layer, and a mass block is arranged above the insulating layer;

The first friction layer and the second friction layer are arched and opposite in direction, the first friction layer is attached with a positive electric sequence friction layer, and the second friction layer is opposite to an electric sequence of the positive electric sequence friction layer and can be in contact with and separated from the positive electric sequence friction layer under the driving of the mass block.

Furthermore, the first friction layer and the second friction layer are connected by the strong adhesive tape to form an arch, and the contact and separation between the two layers are realized by the recovery tension of the adhesive tape, so that the traditional spring structure is replaced, the preparation cost is saved, and the complexity of the device structure is reduced.

Furthermore, the first friction layer and the second friction layer are made of insulating flexible films, so that the sensor has strong mechanical impact resistance, the service life of the sensor is prolonged, and the sensor has good optical characteristics.

Further, the insulating flexible film is made of polyethylene terephthalate, polyvinyl chloride or polyethylene.

further, the positive electric sequence friction layer material adopts polyformaldehyde, ethyl cellulose, polyamide, melamine or fibroin.

Further, the positive electrical sequence friction layer is sprayed on the first friction layer by a spray coating technique. The positive electric sequence friction layer attached to the first friction layer is prepared by a spraying technology with simple operation and low cost, and the mass production of the sensor can be realized.

Furthermore, through holes are formed in the two sides of the insulating shell, and the first conducting wire and the second conducting wire penetrate out of the corresponding through holes respectively to be connected with an external circuit.

further, the theory of the high-sensitivity self-powered acceleration sensor is a brand-new V-Q-a model which can be expressed as follows:

Where v (t) is an output voltage between the first electrode layer and the second electrode layer at a certain time t, a is an acceleration acting on the sensor, t is a time of movement of the friction layer, R is an external resistor, Q is a transferred charge amount, S is an area of the friction layer, ∈ 0 is a vacuum dielectric constant, σ is a surface charge density of the friction layer, d0 ═ d1/∈ 1+ d2/∈ 2 is an equivalent thickness of the friction layer, d1 is thicknesses of the first friction layer and the second friction layer, ∈ 1 is a dielectric constant of the first friction layer and the second friction layer, d2 is a thickness of the positive electric series friction layer, and ∈ 2 is a dielectric constant of the positive electric series friction layer.

The preparation method of the high-sensitivity self-powered acceleration sensor is characterized by comprising the following steps of:

Step a), selecting a cuboid insulating shell, and punching a round hole with the diameter of 1-10 mm on the left side and the right side respectively;

b), selecting two insulating flexible films with the same area and attached with conductive layers, and uniformly spraying a positive electric sequence friction layer material solution on the surface of one side of one insulating flexible film without the conductive layer by using a spray gun filled with the positive electric sequence friction layer material solution;

Step c), fixing electrode lead points on the surfaces of the first and second film conductive layers, and connecting wires with the electrode lead points;

Step d), two side edges of the two films are mutually contacted, and the conductive layers face outwards to form an arch shape and are mutually connected through a strong adhesive tape;

Step e), connecting the insulating layer with the second electrode layer by using a strong adhesive tape, and fixing the mass block above the insulating layer to form an internal sensing system; and encapsulating the internal sensing system in an insulating shell to form the high-sensitivity self-powered acceleration sensor.

further, the spraying process in step b): spraying is carried out in a high-temperature environment of 80-200 ℃, and after 3-10 cycles, the spraying duration is 5-15 s in each cycle, and the time interval of each cycle is 10-20 min.

The high-sensitivity self-powered acceleration sensor has the beneficial effects that: the peak value of the open-circuit voltage is measured to exceed 250V, the peak value of the short-circuit current is measured to exceed 5.7 muA, 100-200 commercial LED bulbs can be instantly and simultaneously lighted, the output power density is greater than 370m W/m2, and the LED bulb has high stability, good repeatability and consistency. The corresponding sensitivity is as high as 20.4 V.s 2/m, and compared with the reported self-powered acceleration sensor, the sensitivity is improved by more than 5 times. And the sensitivity measured by the experiment is highly consistent with the calculation result of the theoretical model. Adopt self-powered form, compare in current MEMS acceleration sensor more nimble, do not receive external restraint, green has wider range of application, has wearable, can regard as wearable alarm device and vibration detecting system.

The preparation method of the invention has the following beneficial effects: the device has simple manufacturing process and low cost, and can realize large-scale production.

drawings

fig. 1 is a schematic cross-sectional view of the present invention.

Fig. 2 is a static state diagram of the present invention.

Fig. 3 is a schematic diagram of the present invention when subjected to upward acceleration.

fig. 4 is a schematic diagram of the present invention when subjected to downward acceleration.

FIG. 5 is a theoretical model analysis diagram of the present invention.

fig. 6 is a graph of the output voltage of the present invention under the condition that a is 9m/s 2.

FIG. 7 is a graph comparing theoretical and experimental data for the present invention under different acceleration conditions.

FIGS. 8 (a) - (e) are process flow diagrams of the present invention.

In the figure: 1-an insulating shell, 2-a mass block, 3-an insulating layer, 4-a second electrode layer, 5-a second friction layer, 6-a positive charge sequence friction layer, 7-a first friction layer, 8-a first electrode layer, 9-a first round hole, 10-a second round hole, 11-a first lead, 12-a second lead, 13-a first electrode lead point, 14-a second electrode lead point, and 15-a spray gun.

Detailed Description

The present invention is further illustrated by the following examples, which are not intended to limit the invention to these embodiments. It will be appreciated by those skilled in the art that the present invention encompasses all alternatives, modifications and equivalents as may be included within the scope of the claims.