CN105158656A - Circular parallel electrode object dielectric property detection clamping device and detection method thereof - Google Patents

Abstract

The invention discloses a clamping device for detecting the dielectric properties of a circular parallel electrode object and a detection method thereof. The lower parallel electrode plate is fixedly placed on the base of the device to keep it horizontal; the upper parallel electrode plate is connected to the bracket through a sliding adjustment device, and the bracket It is connected to the base; by adjusting the coarse adjustment device and the fine adjustment device, the upper plate connected to the bracket can be translated up and down, so as to realize the change of the distance between the two plates and the effective parallel clamping of the clamped object; It also has a sliding rheostat, through which the distance between the parallel plates is converted into electrical signals through the sliding rheostat and the distance measuring circuit, and then displayed on the display through the operation of the single-chip microcomputer. The present invention can realize the effective parallel clamping of the clamped object with proper clamping force when detecting the electrical characteristics of the object, and can timely and accurately read the distance when clamping; the present invention is more convenient to operate than the traditional clamper, and the quality of the detection And higher precision, direct display of relevant information and other advantages.

Description

A clamping device for detecting dielectric properties of a circular parallel electrode object and its detection method

technical field

The invention relates to a circular parallel plate electrode clamping device for quickly detecting the dielectric constant of an object and a detection method thereof, belonging to the technical field of detection instruments.

Background technique

At present, the water shortage detection of crops has become a major problem in agricultural engineering. Although the traditional drying and weight loss method can accurately obtain the moisture content of crops, this method has a long cycle and cannot perform live detection, so it has certain limitations. In recent years, with the rapid development of science and technology, some advanced technologies have been applied to the detection of moisture content of crop leaves, including spectral technology and electrical characteristics. As far as the electrical characteristic technology is concerned, the dielectric constant is an attribute of the object, so as long as the relationship between the water content and the dielectric constant is determined, the water content of the sample can be predicted by the dielectric constant. The present invention is researched on the basis of this background and is a circular parallel plate electrode clamping device for quickly detecting the dielectric constant of an object.

Most of the existing technologies and products are relatively simple to manufacture and cannot achieve strict mutual parallelism between the two plates, which greatly affects the measurement accuracy and produces great errors; in addition, it is impossible to directly measure the distance between the plates, and it is necessary to Manual measurement in the later stage increases the difficulty and process of operation, which is not convenient; the clamping of objects without intuitive performance depends entirely on personal feeling, and it is difficult to achieve the purpose of clamping objects with appropriate clamping force.

Contents of the invention

The object of the present invention is to: provide a circular parallel plate electrode clamping device and its detection method for quickly detecting the dielectric constant of an object, so that the process of measuring the dielectric constant of an object is convenient and simple, and can effectively reduce the error in the measurement operation process , to improve the accuracy of measurement. The present invention overcomes the defects of the previous products above, and has the advantages of convenient operation, higher detection quality and precision, direct display of relevant information, and the like. The invention can be used in experiments for measuring the dielectric constant of most objects.

The invention adopts the following technical solutions: a clamping device for detecting the dielectric properties of a circular parallel electrode object, including a metal base, a non-metallic bracket, a lower parallel electrode plate, an upper parallel electrode plate, a sliding adjustment device, a pressure determination device, and a sliding rheostat ;

The metal base has four feet, one side of the metal base is fixedly connected to one end of the non-metallic support, the other end of the non-metallic support is provided with a sliding adjustment device, the sliding adjustment device is fixedly connected with a connecting column, and the lower end of the connecting column is an upper parallel The electrode plate, and the upper insulating ceramic is connected between the connecting column and the upper parallel electrode plate, and the upper parallel electrode plate can move up and down in parallel by adjusting the coarse adjustment device and the fine adjustment device on the sliding adjustment device; Each device is equipped with a high-precision sliding rheostat; the lower end of the upper parallel electrode plate is facing the lower parallel electrode plate, and the upper parallel electrode plate and the lower parallel electrode plate are parallel to each other. The lower parallel electrode plate is fixed on the metal base, and the lower parallel electrode plate is The lower insulating ceramic is connected between the electrode plate and the metal base;

Each electrical device of the pressure determination device is arranged in a placement groove provided by the metal base, including a single-chip microcomputer, an overvoltage indicator light, a pressure indicator light, a pressure sensor, a display screen, and a sliding rheostat. The pressure sensor is installed on the lower insulating ceramic Between the metal base, the pressure sensor and the sliding rheostat are connected to the input port of the single-chip microcomputer, and the over-voltage indicator light, the pressure indicator light and the display screen are connected to the output port of the single-chip microcomputer.

Further, the plates of the lower parallel electrode plate and the upper parallel electrode plate are circular, with a diameter of 4 cm and a thickness of 1 cm, and the material is copper or aluminum.

Further, the lower parallel electrode plate, the lower insulating ceramic, and the metal base are snapped together and reinforced with glue, and the upper parallel electrode plate, the upper insulating ceramic, and the connecting column are snapped together. connected and reinforced with glue; the upper insulating ceramics and the lower insulating ceramics are designed to be cylindrical, and there are lead channels for guiding and connecting the wires of the upper parallel electrode plate and the lower parallel electrode plate respectively, leading out the circuit and setting the terminal. Easy to connect with pressure determination device.

Further, the coarse adjustment device is composed of a coarse gear, a first helical wheel whose shaft end passes through the coarse gear, and a coarse tooth straight-through sliding track, and the fine adjustment device is composed of a fine gear, a second helical wheel whose shaft end passes through the fine gear, The fine-toothed straight-through sliding track is composed of two fine-toothed straight-through sliding tracks, which are located on both sides of the coarse-toothed straight-through sliding track;

The coarse gear and the coarse-toothed straight-through sliding track are docked with each other, and the fine gear and the fine-toothed straight-through sliding track are butted with each other, and the gear drives the sliding track to move up and down by rotating the first helical wheel and the second helical wheel respectively; Coarse gears, fine gears and helical wheel shafts are connected in series and arranged on a non-metallic bracket; the coarse-toothed straight-through sliding track and the fine-toothed straight-through sliding track are located on the same plane and are all set on the connecting column and fixed by riveting with screws. The movement drives the connecting column to move, so that the upper parallel electrode plate moves up and down in parallel.

Further, the resistance parts of the two sliding rheostats are placed on the coarse-toothed straight-through sliding track and the fine-toothed straight-through sliding track, and are respectively riveted and fixed with screws; Fixed by riveting; the resistance of the sliding rheostat changes with the change of the distance between the parallel electrode plates.

Further, the pressure sensor converts the clamping force into pressure. When the object is clamped, the sensor sends a pressure signal to the single-chip microcomputer, and the single-chip microcomputer works and lights up a green light indicating pressure; when the object clamping force is too large, the sensor sends an overpressure signal. The signal is sent to the single-chip microcomputer, and the single-chip microcomputer works and lights up the overvoltage indicator red light to prompt, so as to realize the determination of the clamping degree of the object.

The technical scheme of the method of the present invention is:

A method for detecting the clamping device for detecting the dielectric properties of a circular parallel electrode object, comprising the following steps:

The first step is to turn on the power, adjust the coarse adjustment device and the fine adjustment device in the sliding adjustment device, so that the upper parallel electrode plate moves down and the lower parallel electrode plate closes until the distance between the parallel electrode plates is zero;

The second step is to use the program compiled by the single-chip microcomputer and the set button to clear the spacing;

The third step, after the zeroing is completed, set the pressure overload point according to the current pressure and the nature of the measured object;

Step 4: Move the upper parallel electrode plate to widen the distance, and then put the object until there is no obvious gap between the object and the parallel electrode plate, and the pressure overload red light is not on;

The fifth step is to connect the reserved connecting wire with the electric clip of the pressure determination device;

In the sixth step, the resistance value of the measuring resistance in the sliding rheostat changes with the change of the distance between the parallel electrode plates, and the electrical signals are transmitted to the single-chip microcomputer through the pins ANIN1 and ADIN2 respectively; The corresponding digital signal can be obtained, and the distance between the two polar plates of D can be obtained through the distance measurement formula, that is, the thickness of the object, and the relevant information is displayed on the display, and the operator reads and records the data.

Further, the measurement formula for the distance between parallel electrode plates in step 6 is: D=K ₀ (I′ ₀ −I ₀ )+K ₁ (I′ ₁ −I ₁ ), where, in the reset state: During detection: R ₁ and R ₃ are the resistance values of the wires in the circuit, R ₂ is the sliding rheostat of the coarse adjustment device, R ₄ is the sliding rheostat of the fine adjustment device, I ₀ is the current on the sliding rheostat of the coarse adjustment device, and I ₁ is the sliding rheostat of the fine adjustment device The current of the rheostat, E is the supply voltage.

The working principle of the present invention is: using a pressure sensor, the object will not be damaged when it is clamped, so that the object can be clamped by an appropriate clamping force; using the change of the resistance of the sliding rheostat and the change of the current of the circuit, the indirect measurement The thickness of the object can be obtained; the data in the present invention can be processed by the single-chip microprocessor, and the dielectric constant of the crop blade can be indirectly measured and the purpose of buffering can be achieved. The specific implementation steps are as follows: This scheme is designed based on the principle of parallel plate capacitors. Move the upper plate up and down to change the distance between the plates to clamp the object, and then use the pressure sensor to determine the maximum clamping force, so that the object will not be clamped in the clamped state. When the pressure between the two plates is fixed, the thickness of the object can be indirectly measured by the change of the current in the circuit caused by the change of the resistance of the sliding rheostat. Using fixed electrode plates, the size of the selected parallel electrode plates should be moderate, which can basically cover the size of the object sample, and facilitate the calculation of the effective area. According to the LCR circuit, the capacitance C of the crop blade between the two pole plates can be measured. The above parameters can be processed by a single chip microcomputer to obtain the dielectric constant of the crop leaves.

An object of the present invention is, in the above-described device and method for measuring the dielectric constant, to ensure that the dielectric constant of the object is measured when the object is clamped by an appropriate clamping force and is not damaged, wherein the object needs to be measured thickness of. The invention uses a pressure sensor to indirectly detect the clamping force to achieve the purpose of clamping; the invention designs an automatic measurement and display device for object thickness, which can quickly and accurately measure the thickness of the object. At the same time, the single-chip computer is used to process the data of the system, and the dielectric constant of the crop leaves can be obtained, and the data buffer and output functions are designed. Achieve the measurement and record of the dielectric constant of crop leaves.

Compared with existing related devices, the present invention has the following advantages:

(1) The existing related devices do not effectively control the clamping force, and the object cannot be clamped by an appropriate clamping force. On the one hand, the object is easily damaged, and on the other hand, the measurement accuracy is affected. The invention improves this, and ensures that the object is clamped by proper clamping force.

(2) The existing related device regulator is relatively crude, and the operation method is not humanized, and it is easy to cause damage to the measured object. The adjusting device of the present invention refers to the adjusting structure of the microscope, and the operation is simple and easy to use, and the object will not be damaged if the correct operation is performed.

(3) The existing related devices are not well controlled to maintain the parallel state of the pole plates, which affects the accuracy of measurement. The present invention improves on this, and ensures that the two pole plates are always kept parallel to each other during the process of adjusting the spacing to clamp the object in the way of up and down translation, so as to achieve the accuracy of measurement.

(4) The existing related device detects the thickness of the object after measurement, and the error is relatively large. The invention utilizes a measurement circuit in which the resistance value of the sliding rheostat changes with the distance, realizes the real-time measurement of the object distance, greatly reduces the error in the operation process, and improves the detection accuracy.

(5) The existing relevant devices do not store and display the relevant detection data. The invention uses a single-chip microprocessor and a display screen to process, store and display the real-time detected data, which is convenient for operators to consult and other related operations.

(6) The sliding adjustment device connects the upper parallel pole plate with the bracket, and its adjustment can change the upper and lower positions of the upper pole plate, thereby changing the distance between the pole plates to clamp the object for measurement. The thick screw on the sliding adjustment device is used for coarse adjustment, and the thin screw is used for fine adjustment, and cooperate with each other to achieve the purpose of accurately adjusting the clamping force.

Description of drawings

Fig. 1 is a structural diagram of a circular parallel plate electrode clamping device for quickly detecting the dielectric constant of an object provided by the present invention;

Fig. 2 is a schematic structural diagram of a pressure determining device provided by the present invention;

Fig. 3 is a structural schematic diagram of a sliding adjustment device provided by the present invention;

Fig. 4 is a schematic diagram of a circuit diagram for measuring the distance between electrode plates provided by the present invention;

FIG. 5 is a schematic flow chart of data information processing provided by the present invention.

Detailed ways:

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention.

In describing the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", " The orientations or positional relationships indicated by "vertical", "horizontal", "top", "bottom", "inner" and "outer" are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and Simplified descriptions, rather than indicating or implying that the device or element referred to must have a particular orientation, be constructed and operate in a particular orientation, and thus should not be construed as limiting the invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, a feature defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

As shown in Figure 1, in the device of the present invention, comprise metal base 1, non-metal support 2, circular parallel electrode plate (lower parallel electrode plate 3, upper parallel electrode plate 4), sliding adjusting device 5, connecting column 6, Upper insulating ceramic 7, lower insulating ceramic 8, pressure determining device 9; wherein, circular parallel electrode plates, metal base 1 and non-metal support 2 form the main body of the device; One side is fixedly connected to one end of the non-metallic support 2, and the other end of the non-metallic support 2 is provided with a sliding adjustment device 5. One side of the sliding adjustment device 5 is fixed with a connecting column 6, and the lower end of the connecting column 6 is connected to the upper parallel electrode plate 4. There is an upper insulating ceramic 7, and by adjusting the coarse adjustment device and the fine adjustment device on the sliding adjustment device 5, the upper parallel electrode plate 4 moves up and down in parallel; the lower end of the upper parallel electrode plate 4 is facing the lower parallel electrode plate 3, and the upper parallel electrode plate 4 There is a certain distance between the plate 4 and the lower parallel electrode plate 3 and they are parallel to each other. The lower parallel electrode plate 3 is fixed on the metal base 1 , and a lower insulating ceramic 8 is connected between the lower parallel electrode plate 3 and the metal base 1 .

1. Design of parallel electrode plates. The present invention is based on the principle of parallel plate capacitors, therefore, the design of parallel electrode plates is very important. The rules for plate design are as follows: ①. The plane of the plate should be smooth and flat to reduce errors. ②. The polar plate should be conducted as little as possible with other metal objects to eliminate the edge effect as much as possible. Therefore, the designed pole plate is circular, moderate in size and thickness. The diameter is 4cm, the thickness is 1cm, and the material is copper or aluminum.

2. The design of the metal base 1 design. The metal base should support the whole device, therefore, the base should be designed to be firm and stable. The four-bottom foot design is adopted, and the material is selected as metal considering factors such as the firmness of the base and the design and processing. Metal base also will install lower parallel pole plate 3 on it except supporting whole device, devices such as pressure sensor, single-chip microprocessor, display screen, power supply, will reasonably set up each device placement port, and circuit wire embedding groove.

3. Each electrical device of the pressure determination device 9 is set in the placement groove provided by the metal base 1, including a single-chip microcomputer, an overvoltage indicator light, a pressure indicator light, a pressure sensor, a display screen, a sliding rheostat, and a power supply. Set between the lower insulating ceramic 8 and the metal base 1 (as shown in Figure 2), the single-chip microcomputer is connected to the overvoltage indicator light, the pressure indicator light, the pressure sensor, the display screen, the sliding rheostat, and the power supply respectively, and the power supply is connected to the single-chip microcomputer. The power port, the pressure sensor and the sliding rheostat are connected to the input port of the single-chip microcomputer, and the overvoltage indicator light, the pressure indicator light and the display screen are connected to the output port of the single-chip microcomputer, wherein the display screen can display the data detected in real time.

4. The design of the connection between the lower parallel electrode plate 3 and the metal base 1 . The lower parallel electrode plate 3 and the metal base 1 are isolated by insulating ceramics 8 to eliminate the electromagnetic influence of the metal base as much as possible. The electrode plate, the ceramic insulating material, and the metal base 1 are interlocked with each other and glued together for reinforcement. The insulating ceramic is designed as a cylinder, and there is a lead channel for guiding and connecting the lower parallel electrode plate 3 wires inside, leading out the circuit and setting a terminal to facilitate connection with the pressure determining device 9 .

5. A key and difficult point of the device lies in the proper clamping of the object by the two electrode sheets. The present invention has designed a pressure determining device 9, and the simple structure diagram of the pressure determining device 9 is shown in FIG. 2 . The clamping force of the clamped object is represented by downward pressure, and the pressure sensor for detecting the pressure is installed between the insulating ceramic 8 and the metal base 1 . Working principle: Set the initial pressure. When the clamping force is too large during the test, the pressure sensor receives the information of excessive pressure and converts it into an electrical signal. At this time, the red light of the overpressure indicator light is on to remind the operator of the tester.

6. The design of the sliding adjustment device 5 is as shown in Figure 3. Including coarse adjustment device and fine adjustment device. The coarse adjustment device is composed of a coarse gear 10, a first helical wheel 11 whose shaft end passes through the coarse gear, and a coarse tooth straight-through sliding track 12. wheel 15 and fine-toothed straight-through sliding track 14; the fine-toothed straight-through sliding track 14 is two, located on both sides of the coarse-toothed straight-through sliding track 12; The fine gear 13 and the fine-tooth straight-through sliding track 14 are docked with each other, and the gears drive the sliding track to move up and down by rotating the first helical wheel 11 and the second helical wheel 15 respectively; the coarse gear and the fine gear 13 are connected in series with the helical wheel shaft Together, they are set on the non-metallic bracket 2; the coarse-toothed straight-through sliding track 12 and the fine-toothed straight-through sliding track 14 are located on the same plane and are all arranged on the connecting column 6 and fixed by riveting with screws, and the movement of the slide rail drives the connecting column 6 move, so that the upper parallel electrode plate 4 moves up and down in parallel.

7. Design of sliding rheostat group. The resistance part of the sliding rheostat is placed on the slide rail of the sliding adjustment device and fixed by riveting with screws, and the sliding piece is arranged on the non-metallic support 2 and fixed by riveting with screws. Working principle: adjust the distance between the plates. The sliding adjustment device 5 drives the upper plate to move up and down. At the same time, the resistance of the sliding rheostat and the relative position of the sliding plate change, and the resistance value of the sliding rheostat changes accordingly, thus changing the current in the measurement circuit. The size can be calculated by the single-chip microprocessor to obtain accurate data on the distance between the plates.

8. The design of the connection between the upper parallel electrode plate 4 and the connecting column 6. The upper parallel electrode plate 4 and the connecting column 6 are isolated by an upper insulating ceramic 7, so as to eliminate the electromagnetic influence of the metal base as much as possible. The upper parallel electrode plate 4 , the upper insulating ceramic 7 , and the connecting column 6 are snapped together with each other and are stuck and reinforced with glue. The insulating ceramic is designed as a cylinder, and there is a lead channel for guiding and connecting the 4 wires of the upper parallel electrode plate inside, and the circuit is drawn out and the terminal is set to facilitate the connection with the test instrument.

9. Design of single-chip microprocessor and display screen. The single-chip microprocessor and the display screen are placed in the placement groove opened on the metal base, and are connected with various electrical components through lines. Measure the resistance value of resistors R2 and R4 to change, and transmit the electrical signal to the single-chip microcomputer through the pins ANIN1 and ADIN2 respectively; the single-chip microcomputer receives the electrical signal of the circuit, processes and stores it according to the compiled program, and displays relevant information on the display.

10. Operation method and steps:

(1) Clear the system. Adjust the coarse adjustment device and the fine adjustment device to make the distance between the parallel plates zero, and press the reset button on the base to reset the distance to zero according to the predetermined program, and display it on the display.

(2) Set the pressure point. After the zero clearing is completed, set the pressure overload point according to the current pressure and the nature of the measured object.

(3) Place objects. There is no obvious gap between the object and the plate, and the pressure overload red light is not on.

(4) Connect the analyzer. Connect the reserved link lead to the clamp of the pressure determination device.

(5) Test the dielectric constant of the object.

11. The formula used for spacing measurement:

The distance measurement circuit diagram is shown in Figure 4, where R1 and R3 are the resistance values of the wires in the circuit, R2 is the sliding rheostat of the coarse adjustment device, R4 is the sliding rheostat of the fine adjustment device, I ₀ is the current on the sliding rheostat of the coarse adjustment device, and I ₁ is the current of the sliding rheostat of the fine adjustment device, and E is the power supply voltage.

In cleared state: $\begin{array}{c}{I}_0=\frac{\mathrm{E.}}{R_2+R_1}\\ I_1=\frac{\mathrm{E.}}{R_4+R_3}\end{array},$ During detection: $\begin{array}{c}{I}_0^{\′}=\frac{\mathrm{E.}}{R_2^{\′}+R_1}\\ I_1^{\′}=\frac{\mathrm{E.}}{R_4^{\′}+R_3}\end{array};$

Spacing formula: D=K ₀ (I′ ₀ -I ₀ )+K ₁ (I′ ₁ -I ₁ )

D is the pole plate spacing, K0 is the current spacing coefficient of the coarse adjustment device, and K1 is the current spacing coefficient of the fine adjustment device.

12. The device needs to use a processing system to process the data. Fig. 5 is a flow chart of a data information processing system based on a single chip microcomputer.

Figure 5 shows that the corresponding analog signal can be obtained through the sliding rheostat, and the corresponding digital signal can be obtained through the A/D conversion circuit. The digital signal is imported into the single-chip microcomputer, and the distance between the two plates of D can be obtained through the distance measurement formula. , that is, the thickness of the object. In addition, the pressure determination device controls the indicator light through the single-chip processing system to instruct the operator to operate, so as to achieve the purpose of proper clamping.

In the description of the present invention, it should be noted that unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection. Connected, or integrally connected; it can be mechanically connected or electrically connected; it can be directly connected or indirectly connected through an intermediary, and it can be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention in specific situations.

The clamping device for detecting the dielectric properties of a circular parallel electrode object provided by the present invention has been described above in detail. This paper uses a specific example to illustrate the principle and implementation of the present invention. What is to be explained is , the above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (8)

1. a circular flat column electrode object dielectric property detects clamping device, it is characterized in that, comprise metab (1), non-metal frame (2), lower parallel electrode plate (3), upper parallel electrode plate (4), slidable adjustment device (5), pressure determining apparatus (9), slide rheostat;

Described metab (1) is four foots, the side of metab (1) is fixedly connected with one end of non-metal frame (2), the other end of non-metal frame (2) is provided with slidable adjustment device (5), slidable adjustment device (5) is fixedly connected with joint pin (6), joint pin (6) lower end is upper parallel electrode plate (4), and be connected with insulating ceramics (7) between joint pin (6) and upper parallel electrode plate (4), by the rack and rinion adjustment in adjustment slidable adjustment device (5) and fine tuning device, parallel electrode plate (4) is moved in parallel up and down, rack and rinion adjustment and fine tuning device respectively fill a high-precision slide rheostat, upper parallel electrode plate (4) lower end faces lower parallel electrode plate (3), upper parallel electrode plate (4) and lower parallel electrode plate (3) are parallel to each other, described lower parallel electrode plate (3) is fixed on metab (1), and is connected with lower insulating ceramics (8) between lower parallel electrode plate (3) and metab (1),

Each electric device of described pressure determining apparatus (9) is arranged in the standing groove that metab (1) offers, comprise single-chip microcomputer, overvoltage pilot lamp, have pressure pilot lamp, pressure transducer, display screen, slide rheostat, described pressure transducer is installed between lower insulating ceramics (8) and metab (1), described pressure transducer is connected the input port of single-chip microcomputer with slide rheostat, overvoltage pilot lamp, have pressure pilot lamp and display screen to connect the output port of single-chip microcomputer.

2. circular flat column electrode object dielectric property according to claim 1 detects clamping device, it is characterized in that, the pole plate of described lower parallel electrode plate (3), upper parallel electrode plate (4) is circular, and diameter is 4cm, thickness 1cm, material is copper or aluminium.

3. circular flat column electrode object dielectric property according to claim 1 and 2 detects clamping device, it is characterized in that, between described lower parallel electrode plate (3), lower insulating ceramics (8), metab (1) three, mutual buckle connects and sticks reinforcing with viscose, and between described upper parallel electrode plate (4), upper insulating ceramics (7), joint pin (6) three, mutual buckle connects and sticks reinforcing with viscose; Described upper insulating ceramics (7), lower insulating ceramics (8) are all designed to column type, inside offers the lead channels guiding and connect upper parallel electrode plate (4), lower parallel electrode plate (3) wire respectively, draw circuit and binding post is set, being conveniently connected with pressure determining apparatus (9).

4. circular flat column electrode object dielectric property according to claim 1 and 2 detects clamping device, it is characterized in that, described rack and rinion adjustment is led directly to sliding rail (12) by pinion (10), axle head forms through first helical wheel (11) of pinion, bastard, and described fine tuning device takes turns (13) by serration, axle head leads directly to sliding rail (14) form through second helical wheel (15) of serration wheel, serration; It is two that described serration leads directly to sliding rail (14), is positioned at the both sides that bastard leads directly to sliding rail (12);

Described pinion (10) and bastard lead directly to sliding rail (12) and mutually dock, described serration wheel (13) and serration lead directly to sliding rail (14) and mutually dock, respectively by turn first helical wheel (11), the second helical wheel (15), gear driven sliding rail is moved up and down; Described pinion, serration wheel (13) and spiral wheel shaft are cascaded, and are arranged on non-metal frame (2); Described bastard leads directly to sliding rail (12), serration leads directly to sliding rail (14) and is positioned at same plane and is all arranged on joint pin (6) fixing with screw riveted joint, the moving belt of the slide rail post (6) that is dynamically connected is mobile, thus parallel electrode plate (4) is moved in parallel up and down.

5. circular flat column electrode object dielectric property according to claim 4 detects clamping device, it is characterized in that, the active component of described two slide rheostats is placed on bastard and leads directly to sliding rail (12) and serration leads directly on sliding rail (14), and rivets fixing respectively with screw; The slide plate of described two slide rheostats is arranged on non-metal frame (2) fixing with screw riveted joint; Slide rheostat resistance changes along with the change of parallel electrode plate spacing.

6. circular flat column electrode object dielectric property according to claim 1 detects clamping device, it is characterized in that, holding force is converted to pressure by described pressure transducer, and when object is clamped, sensor has sent pressure signal to single-chip microcomputer, and single-chip microcomputer work has been lighted end finger and shown that green light is pointed out; When object holding force is excessive, sensor sends overvoltage signal to single-chip microcomputer, and the prompting of overvoltage instruction red light is lighted in single-chip microcomputer work, realizes being clamped the determination of degree to object.

7. circular flat column electrode object dielectric property according to claim 1 detects a clamping device detection method, it is characterized in that, comprises the following steps:

The first step, switches on power, and regulates the rack and rinion adjustment in slidable adjustment device (5) and fine tuning device, parallel electrode plate (4) is moved down and closes up with lower parallel electrode plate (3), until parallel pole distance between plates is zero;

Second step, utilizes the good program of single chip compilation and the button set up to reset spacing;

3rd step, after having reset, according to current pressure and testee character set pressure overload point;

4th step, (4) move space out to upper parallel electrode plate, then put into object, until without clear gap between object and parallel electrode plate, and pressure overload red light does not light;

5th step, presss from both sides reserved connection wire with the electricity of pressure determining apparatus (9) and is connected;

6th step, in slide rheostat, the resistance of measuring resistance changes along with the change of parallel pole distance between plates, sends electric signal to single-chip microcomputer respectively by pin ANIN1, ADIN2; The electric signal of single-chip microcomputer receiving circuit, can obtain corresponding digital signal by A/D change-over circuit, and by distance measurement formula, the distance between D two-plate can be obtained, the i.e. thickness of object, and show relevant information over the display, operating personnel read and record data.

8. circular flat column electrode object dielectric property according to claim 7 detects clamping device detection method, and it is characterized in that, in described 6th step, the measure equation of parallel pole distance between plates is: D=K ₀(I ' ₀-I ₀)+K ₁(I ' ₁-I ₁), wherein, under cleared condition: $\begin{array}{c}{I}_0=\frac{E}{R_2+R_1}\\ I_1=\frac{E}{R_4+R_3}\end{array},$ In testing process: $\begin{array}{c}{I}_0^{\′}=\frac{E}{R_2^{\′}+R_1}\\ I_1^{\′}=\frac{E}{R_4^{\′}+R_3}\end{array},$ R ₁, R ₃for the resistance value of electric wire in circuit, R ₂for rack and rinion adjustment slide rheostat, R ₄for fine tuning device slide rheostat, I ₀for the electric current on rack and rinion adjustment slide rheostat, I ₁for the electric current of fine tuning device slide rheostat, E is supply voltage.