CN210774305U

CN210774305U - Weighing and measuring system for railway wagon

Info

Publication number: CN210774305U
Application number: CN201922060285.9U
Authority: CN
Inventors: 张颖超
Original assignee: Nanjing Institute of Railway Technology
Current assignee: Nanjing Institute of Railway Technology
Priority date: 2019-11-26
Filing date: 2019-11-26
Publication date: 2020-06-16
Anticipated expiration: 2029-11-26

Abstract

The utility model discloses a railway freight car weighing and measuring system, including main control unit, a plurality of weighing sensor module, signal processing module, orientation module, gyroscope, wireless transmission module, display module, alarm module, power module. The utility model can realize real-time updating of the cargo data and facilitate subsequent tracing by measuring the weight of the goods loaded in each carriage of the railway wagon in real time and wirelessly transmitting the weight of the goods in each carriage to the weighing terminal; the measurement process is refined to each carriage, so that the measurement accuracy of the system is improved; the safety of the running of the truck is ensured by monitoring the actual load of the truck in real time; in addition, the pressure sensor is connected to the bottom of the carriage through the buffer device, so that the precision reduction of the railway wagon under the high-speed condition is avoided, the problems of insufficient sensitivity and accuracy of the weighing device under the high-speed condition are solved, and the measuring precision and accuracy are improved.

Description

Weighing and measuring system for railway wagon

Technical Field

The utility model relates to a railway freight car load control technical field particularly relates to a railway freight car measurement system that weighs.

Background

Since the new century, with the rapid development of national economy and the increasing of international trade volume, railway transportation is one of five transportation tools in China, and the factors of large transportation volume, safe and reliable transportation, low price and the like occupy a considerable rate in the field of goods transportation, play an important role and play a great help role in the rapid development of socialist economy in China. The increase of railway transportation proportion brings more pressure to railway measurement, and simultaneously ensures the safety of railway freight transportation, the transportation efficiency and the measurement accuracy are gradually proposed by people.

The overload and unbalance loading of the railway freight car are one of the important factors influencing the running safety of the railway freight car, particularly, after the speed of the train is increased in China, the flow of the train is large, the load impact of the overload and unbalance loading on wheel rails is increased, and the damage to the train is serious, so the service life of the freight car is greatly reduced, and accidents caused by long-term overload and unbalance loading running of the train sometimes happen, so that the serious threats are caused to the economy and safety of people, and therefore, the real-time measurement of the loading capacity of the railway freight car is very important in order to restrain the overload and unbalance loading of the train and ensure the safety of goods transportation.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a railway wagon weighing and measuring system, which can wirelessly transmit the weight of goods in each carriage to a weighing terminal by measuring the weight of goods loaded in each carriage of the railway wagon in real time, realize the real-time update of the loaded data and facilitate the follow-up tracing; the measurement process is refined to each carriage, so that the measurement accuracy of the system is improved; the safety of the running of the truck is ensured by monitoring the actual load of the truck in real time; in addition, the pressure sensor is connected to the bottom of the carriage through the buffer device, so that the precision reduction of the railway wagon under the high-speed condition is avoided, the problems of insufficient sensitivity and accuracy of the weighing device under the high-speed condition are solved, and the measuring precision and accuracy are improved.

To achieve the above objective, with reference to fig. 1, the present invention provides that a communication link is established between the weighing and measuring system and the weighing terminal; the weighing and measuring system comprises a main controller, a plurality of weighing sensor modules, a signal processing module, a positioning module, a gyroscope, a wireless transmission module, a display module, an alarm module and a power supply module;

the weighing sensor modules are arranged at the bottom of each carriage of the railway wagon in a one-to-one correspondence manner and are electrically connected with the main controller through the signal processing module, the weighing sensors are used for measuring the weight of goods in each carriage in real time, and measuring signals are amplified by the signal processing module and then converted into sampling signals in a digital format to be sent to the main controller;

the positioning module is arranged on the railway wagon and is electrically connected with the main controller through a serial port, and the positioning module is used for measuring the speed value of the railway wagon in real time and sending the measured speed value to the main controller;

the gyroscope is arranged on the railway wagon and connected with the main controller through a serial port, and is used for measuring the acceleration value and the angular velocity value of the railway wagon in real time and sending the measured acceleration value and the measured angular velocity value to the main controller;

the main controller is arranged in a wagon head control area and is connected with the weighing terminal through a wireless transmission module, the main controller sends the received cargo weight of each carriage, the speed value, the acceleration value and the angular speed value of the railway wagon to the weighing terminal through the wireless transmission module, and the weighing terminal stores the received data into a corresponding memory;

the main controller displays the received cargo weight of each carriage through the display module according to an external control instruction, compares the received cargo weight of each carriage with a load bearing threshold value of the corresponding carriage, and sends an alarm signal to the alarm module to send out sound and light alarm when the cargo weight of any carriage is larger than the load bearing threshold value corresponding to the carriage;

the power supply module is used for providing electric energy required by normal work of the main controller, the weighing sensor modules, the signal processing module, the positioning module, the gyroscope, the wireless transmission module, the display module and the alarm module.

In a further embodiment, the weighing terminal accumulates the weight of the goods in each carriage in real time according to an external control instruction to obtain an actual load value of the railway wagon, and the actual load value of the railway wagon is fed back to the main controller through the wireless transmission module;

the main controller displays the received actual load value of the rail wagon through the display module, and

and comparing the received actual load value of the railway wagon with the load bearing threshold of the railway wagon, and sending an alarm signal to the alarm module to send out an acousto-optic alarm when the actual load value is greater than the load bearing threshold of the railway wagon.

In a further embodiment, the weighing sensor module comprises a plurality of pressure sensors which are distributed at the bottom of the corresponding carriage to form a pressure sensor group;

each pressure sensor is connected to the bottom of the carriage through a buffer device.

In a further embodiment, the damping means comprises a weighing spring.

In a further embodiment, the main controller respectively multiplies the sampling values of the received continuous N-time sampling signals of each pressure sensor by N corresponding weighting coefficients and then accumulates the sampling values to calculate effective sampling values of the pressure sensors;

and N is a positive integer greater than or equal to 1.

In a further embodiment, the pressure sensor is a full-bridge resistance strain gauge type pressure sensor.

In a further embodiment, the wireless transmission module adopts a raspberry pi.

In a further embodiment, the gyroscope includes an MPU-6050 module.

In a further embodiment, the alarm module comprises a warning lamp and a buzzer.

In a further embodiment, the power supply module comprises a dc regulated power supply for converting 220V ac mains power into 3V, 5V, 12V dc voltage.

In a further embodiment, the signal processing module adopts an integrated high-precision analog-to-digital converter, and comprises an amplifying circuit and an analog-to-digital conversion circuit which are connected with each other, and a voltage-stabilized power supply and a clock oscillator which are connected with the amplifying circuit and the analog-to-digital conversion circuit.

The utility model discloses the railway freight car measurement system that weighs mainly comprises main control unit, weighing sensor module, signal processing module, wireless transmission module, orientation module, alarm module, gyroscope, display module, direct current voltage source module etc..

For example, a plurality of pressure sensor measuring nodes are arranged at the bottom of each carriage to form a pressure sensor group, the pressure sensor group forms a voltage signal under the action of the gravity of goods in the carriage, and the generated voltage signal is processed, amplified and subjected to analog-to-digital conversion by a signal processing module and then converted into a digital signal which can be identified by a main controller. Meanwhile, the satellite positioning module measures the speed value of the railway wagon in real time and sends the speed value to the main controller through a serial port; the gyroscope sends the measured acceleration value and angular velocity value to the master controller. The main controller packs and processes all received data and transmits the data to the weighing terminal through the wireless transmission module, and the weighing terminal stores the received data in the memory so that workers can check and verify the data.

This weighing measurement system still has load and reminds and overweight prompt facility except that the real-time recording function, realizes through following two kinds of modes:

first mode

The main controller displays the received cargo weight of each carriage through the display module according to an external control instruction, compares the received cargo weight of each carriage with the load bearing threshold value of the corresponding carriage, and sends an alarm signal to the alarm module to send out sound and light alarm when the cargo weight of any carriage is larger than the load bearing threshold value corresponding to the carriage.

This mode has all set up the weight bearing threshold value to every section carriage, and wherein the cargo weight in arbitrary one section carriage has surpassed corresponding weight bearing threshold value, and alarm module all can send the warning suggestion, simultaneously, shows the cargo weight in every section carriage in real time through display module, corresponds the weight bearing threshold value in carriage even to guide the freight train staff to combine cargo weight and goods to mention the assembly position of rational distribution every goods. The mode monitors the loading of the truck from the loading angle of each carriage, and is more suitable for occasions with more types of transported articles or higher load limitation on part or all carriages

Second mode

The weighing terminal accumulates the weight of the goods in each carriage in real time according to an external control instruction to obtain an actual load value of the railway wagon, and the actual load value of the railway wagon is fed back to the main controller through the wireless transmission module;

The weighing terminal obtains the actual load value of whole railway freight car after combining the goods weight of every section of carriage that receives and add up, and on passing through wireless transmission module with actual load value conveyed main control unit again, show through display module, when the actual load has exceeded freight car load capacity threshold value, order about alarm module and send alarm information to remind the freight car staff to stop continuing to load.

The mode monitors the loading of the truck from the angle of integral load, and is more suitable for occasions where the transported goods are more uniform or the load limit values of part or all of the carriages are lower.

Preferably, the weighing terminal may further perform data quality control on the actual load value in combination with the received velocity value and acceleration value, so as to correct the actual load of the truck, where the data quality control of the weighing terminal mainly corrects the corrected cargo weight of each compartment in combination with the velocity value, the acceleration value, and the like, and then calculates a sum, because different velocities and accelerations of the rail wagon during traveling may generate different error offsets to the measured cargo weight, for example, the greater the velocity value, the higher the dynamic load frequency and amplitude, the greater the influence on the accuracy of the symmetric weight; when the acceleration is not equal to zero, the single-shaft weighing instantaneous value can generate an error which is in direct proportion to the acceleration, and the weighing result generates a large deviation and the like. Therefore, the corrected cargo weight of each car is corrected again in combination with the velocity value, the acceleration value, and the like, and a more accurate cargo weight value can be obtained.

The utility model discloses still mention, link to each other buffer such as weighing sensor and weighing spring, the one end of weighing spring and railway freight car's carriage bottom link to each other, and the other end and weighing sensor link to each other, conduct the gravity of goods in the carriage to weighing sensor through weighing spring on, make weighing sensor take place deformation, produce signal output, realize the weight measurement of goods in the carriage. Because be connected with the weighing spring between freight train carriage and the weighing sensor, avoided the precision decline that railway freight car produced under the high-speed condition, for example, the weighing spring leads to on the weighing sensor after the extra pressure that leads to such as the carriage slightly jolts, rocks, can effectively reduce measuring error, realizes the accurate measurement of goods weight of railway freight train under high-speed operation.

The alarm module is arranged in a control area of the head of the truck and consists of a red light and a buzzer. When the actual loading capacity of goods surpassed the bearing capacity threshold value of freight train, the red light will be lighted, and bee calling organ sends out alarm sound simultaneously, reminds the staff to stop continuing the device, in time handles the goods quantity of having loaded, avoids pressure sensor to damage. The display module is connected with the controller and can display the weight information of the cargos in the weighing compartment in real time.

Above the technical scheme of the utility model, compare with current, its beneficial effect who is showing lies in:

(1) the utility model discloses use satellite positioning module, gyroscope and weighing sensor module, will weigh, speed and acceleration, angular velocity data convey the terminal in real time, realize the real-time storage of data, make things convenient for the staff to call data and handling data.

(2) The utility model discloses monitor the freight train load from two angles of every section carriage load and the whole load of railway freight train respectively according to application, monitoring effect is good, helps staff rational distribution goods loading position simultaneously.

(3) The system uses the buffer devices such as the weighing spring to connect the wagon with the pressure sensor for weighing, avoids the reduction of weighing precision caused by the high-speed running of the railway wagon, and realizes the accurate measurement of the weight of goods of the railway wagon in the high-speed running.

(4) The system is simple in structure in design, the problems of inaccurate precision, voltage drift and the like are solved, and the modular design mode is convenient for later-stage expansion and maintenance.

It should be understood that all combinations of the foregoing concepts and additional concepts described in greater detail below can be considered as part of the inventive subject matter of the present disclosure unless such concepts are mutually inconsistent. In addition, all combinations of claimed subject matter are considered a part of the inventive subject matter of this disclosure.

The foregoing and other aspects, embodiments and features of the present teachings can be more fully understood from the following description taken in conjunction with the accompanying drawings. Additional aspects of the present invention, such as features and/or advantages of exemplary embodiments, will be apparent from the description which follows, or may be learned by practice of the specific embodiments in accordance with the teachings of the present invention.

Drawings

The drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures may be represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. Embodiments of various aspects of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which:

fig. 1 is a schematic block diagram of the railway wagon weighing and measuring system of the present invention.

Detailed Description

For a better understanding of the technical content of the present invention, specific embodiments are described below in conjunction with the accompanying drawings.

With reference to fig. 1, the present invention provides that a communication link is established between the weighing and measuring system 100 and the weighing terminal 200; the weighing and measuring system 100 comprises a main controller 1, a plurality of weighing sensor modules 2, a signal processing module, a positioning module 3, a gyroscope 4, a wireless transmission module 7, a display module 5, an alarm module 6 and a power supply module 8.

The weighing sensor modules 2 are arranged at the bottom of each carriage of the railway wagon in a one-to-one correspondence mode and are electrically connected with the main controller 1 through the signal processing module, the weighing sensors are used for measuring the weight of goods in each carriage in real time, and measuring signals are amplified by the signal processing module and then converted into sampling signals in a digital format to be sent to the main controller 1.

The positioning module 3 is installed on a railway wagon and is electrically connected with the main controller 1 through a serial port, and the positioning module 3 is used for measuring the speed value of the railway wagon in real time and sending the measured speed value to the main controller 1.

The gyroscope 4 is installed on a railway wagon and connected with the main controller 1 through a serial port, and the gyroscope 4 is used for measuring the acceleration value and the angular velocity value of the railway wagon in real time and sending the measured acceleration value and the measured angular velocity value to the main controller 1.

The main controller 1 is installed in a wagon head control area and is connected with the weighing terminal 200 through the wireless transmission module 7, the main controller 1 sends the received cargo weight of each carriage, the speed value, the acceleration value and the angular speed value of the wagon to the weighing terminal 200 through the wireless transmission module 7, and the weighing terminal 200 stores the received data into a corresponding memory.

The main controller 1 displays the received cargo weight of each carriage through the display module 5 according to an external control instruction, compares the received cargo weight of each carriage with the load bearing threshold of the corresponding carriage, and sends an alarm signal to the alarm module 6 to give out an audible and visual alarm when the cargo weight of any carriage is larger than the load bearing threshold corresponding to the carriage.

The power module 8 is used for providing electric energy required by normal work of the main controller 1, the plurality of weighing sensor modules 2, the signal processing module, the positioning module 3, the gyroscope 4, the wireless transmission module 7, the display module 5 and the alarm module 6.

In a further embodiment, the weighing terminal 200 accumulates the weight of the goods in each carriage in real time according to an external control instruction to obtain an actual load value of the railway wagon, and feeds the actual load value of the railway wagon back to the main controller 1 through the wireless transmission module 7;

the main controller 1 displays the received actual load value of the railway wagon through the display module 5, and

and comparing the received actual load value of the railway wagon with the load bearing threshold of the railway wagon, and sending an alarm signal to the alarm module 6 to send out an audible and visual alarm when the actual load value is greater than the load bearing threshold of the railway wagon.

In some examples, the load cell module 2 includes a plurality of pressure sensors distributed on the bottom of the corresponding compartment to form a pressure sensor group. Each pressure sensor is connected to the bottom of the carriage through a buffer device, for example, a weighing spring is used as the buffer device.

The pressure sensor adopts the foil gage principle to measure, and when the sheetmetal received pressure, mechanical deformation led to resistance to change, and the size and the atress size of deformation are direct ratio relation, for example adopt full bridge resistance foil gage, when pressure sensor experienced pressure variation, can produce the change of voltage at the output, realize weight measurement. However, in some cases, it is possible that the output signal is weak, for example, there is the change that can not be sensitive to detect voltage in the controller when empty car state or few goods, for this reason, the utility model provides a, through signal processing circuit connection weighing sensor and main control unit 1, send weighing sensor's sampling signal to main control unit 1 after through signal processing circuit amplification processing again and do further identification processing.

The signal processing module comprises an amplifying circuit and an analog-to-digital conversion circuit which are connected with each other. For example, an integrated high-precision analog-to-digital converter is adopted, and the integrated high-precision analog-to-digital converter simultaneously comprises a signal amplification module, a high-precision analog-to-digital converter and peripheral circuits such as a voltage-stabilized power supply and a clock oscillator which are required for completing amplification and conversion functions, so that the circuit structure design is simplified, and the integrated high-precision analog-to-digital converter has the advantages of high precision, low cost, strong anti-interference capability, high response speed and the.

The wireless transmission module 7 can directly pack the data sent by the main controller and send the data to the weighing terminal for processing and receive the data actively sent by the weighing terminal (at this moment, the wireless transmission module is only equivalent to a simple signal transceiver), and can also adopt a raspberry group, for example, the raspberry group is 3 generation B +. If adopt the raspberry group, wireless transmission module 7 is equivalent to a small computer in whole weighing and measuring system 100, can realize more complicated data receiving and dispatching (like initiatively visiting the terminal of weighing etc.), and main control unit 1 will gather the completion and the data packing after quality control sends to the raspberry group in, and the raspberry group is as the transfer node, visits through the mode of remote access to the memory of weighing terminal 200, inserts received data in the memory, accomplishes data real-time update. The raspberry pie is connected with the main controller 1 through a serial port, weighing data, speed data, acceleration data and the like collected by the main controller 1 are sent to the raspberry pie through the serial port, the raspberry pie accesses data in the weighing terminal 200 in a remote direction, new data information is added to the weighing terminal 200, and later data quality control is facilitated.

The gyroscope 4 adopts a 6-axis gyroscope 4, the 6-axis gyroscope 4 consists of a gravity accelerometer and a 3-axis gyroscope 4, the gravity accelerometer measures 3-axis acceleration values of the vehicle, and the 3-axis gyroscope 4 measures 3-axis angular velocity values of the vehicle. For example, an MPU-6050 module can be adopted, a voltage stabilizing circuit is arranged in the module, the module can be compatible with a 3.3V/5V embedded system, the connection is convenient, a digital filtering technology is adopted, the measurement noise can be effectively reduced, the measurement value is improved, an attitude resolver is integrated in the module, the dynamic Kalman filtering algorithm is matched, the current attitude of the module can be output under the dynamic environment, the attitude measurement precision is 0.01 degree, and the stability is high.

The power module 8 selects a direct current stabilized voltage power supply for converting 220V alternating current into 15V and 9V alternating current through voltage reduction, and then converts the voltage into 3V, 5V and 12V direct current voltage through a voltage stabilizing and filtering circuit, and each module is powered by the power module 8.

In some examples, the analog signal input to the main controller 1 sometimes includes various noises and interferences from the signal source itself to be measured, the sensor, and the external interference signal. To this kind of situation, in order to eliminate the noise and the interference of being surveyed the signal, the utility model provides a, realize getting rid of interference signal through predetermined weighted average filtering algorithm.

The principle of weighted average filtering is that the continuous N times of sampling values are respectively multiplied by different weighting coefficients and then accumulated, and the weighting coefficients are generally small and large first so as to highlight the effect of a plurality of subsequent sampling and enhance the knowledge of the system on the parameter variation trend. Each weighting coefficient is smaller than the decimal of 1, and the result condition that the sum is equal to 1 is met, so that the accumulated sum after weighting operation is the effective sampling value. The weighted average filtering is a trend prediction method which uses a plurality of observed values of the same variable arranged according to a time sequence in the past and takes the time sequence as a weight to calculate the weighted arithmetic mean of the observed values, and takes the number as a predicted value of the variable in a future period.

The difference equation for a known first order inertial filter is:

wherein y (k) is the output of the filter at the kth sampling moment, x (k) is the original signal with interference at the kth sampling moment, and C (1), ┄, C (n) are weighting coefficients, and satisfy the following formula:

weighted average filtering is to average N samples, but it is different from arithmetic average filtering and moving average filtering in that each sample has different influence on the result, i.e. the weights are different, and the new sample data has the largest weight and the closer to the current time, the larger the weight is.

In the case where the load cell module 2 is composed of a plurality of pressure sensors, the processing method is as follows:

the main controller 1 collects the measurement signals of each pressure sensor, respectively selects N sampling values for respective collected data, performs weighted average filtering calculation to obtain the filtering value of each pressure sensor, calculates the weighted arithmetic mean of the sampling values of the section, and takes the finally calculated value as the measurement value of the weighing sensor.

Based on aforementioned railway freight car weighing measurement system 100, the utility model also provides a railway freight car weighing measurement system 100's working method, working method includes:

s1: measuring the weight of the goods in each carriage in real time, amplifying the measurement signals, converting the amplified measurement signals into sampling signals in a digital format, filtering interference signals contained in the sampling signals by adopting a preset filtering rule, and calculating to obtain the corrected weight of the goods in each carriage;

the speed value of the railway wagon is measured in real time by adopting a positioning module 3;

measuring the acceleration value and the angular velocity value of each carriage in real time by adopting a gyroscope 4;

s2: the received corrected cargo weight of each carriage, the speed value, the acceleration value and the angular speed value of the railway wagon are sent to the weighing terminal 200 through the wireless transmission module 7, so that the weighing terminal 200 calculates the actual load value of the railway wagon by combining the corrected cargo weight, the acceleration value, the angular speed value and the speed value of the railway wagon of each carriage;

s3: receiving the actual load value of the rail wagon fed back by the weighing terminal 200, displaying the received actual load value of the rail wagon through the display module 5, and

and comparing the received actual load value of the railway wagon with the load bearing capacity threshold value of the railway wagon, and sending out an audible and visual alarm when the actual load value is greater than the load bearing capacity threshold value of the railway wagon.

In this disclosure, aspects of the present invention are described with reference to the accompanying drawings, in which a number of illustrative embodiments are shown. Embodiments of the present disclosure are not necessarily defined to include all aspects of the invention. It should be appreciated that the various concepts and embodiments described above, as well as those described in greater detail below, may be implemented in any of numerous ways, as the disclosed concepts and embodiments are not limited to any implementation. Additionally, some aspects of the present disclosure may be used alone or in any suitable combination with other aspects of the present disclosure.

Although the present invention has been described with reference to the preferred embodiments, it is not intended to limit the present invention. The present invention is intended to cover by those skilled in the art various modifications and adaptations of the invention without departing from the spirit and scope of the invention. Therefore, the protection scope of the present invention is subject to the claims.

Claims

1. A weighing and measuring system of a railway wagon is characterized in that a communication link is established between the weighing and measuring system and a weighing terminal; the weighing and measuring system comprises a main controller, a plurality of weighing sensor modules, a signal processing module, a positioning module, a gyroscope, a wireless transmission module, a display module, an alarm module and a power supply module;

2. The weighing and measuring system of the railway wagon of claim 1, wherein the weighing terminal accumulates the weight of the goods in each carriage in real time according to an external control instruction to obtain an actual load value of the railway wagon, and feeds the actual load value of the railway wagon back to the main controller through the wireless transmission module;

3. The rail wagon weighing and measuring system of claim 1, wherein the weighing sensor module comprises a plurality of pressure sensors distributed at the bottom of the corresponding carriage to form a pressure sensor group;

4. A rail wagon weighing measuring system as claimed in claim 3, wherein the damping means comprises a weighing spring.

5. A rail wagon weighing and measuring system as claimed in claim 3, wherein the pressure sensor is a full bridge resistance strain gauge type pressure sensor.

6. A rail wagon weighing and measuring system as claimed in any one of claims 1-5, wherein the wireless transmission module is a raspberry pie.

7. A rail wagon weighing measuring system as claimed in any one of claims 1-5, wherein the gyroscope comprises an MPU-6050 module.

8. The railway wagon weighing and measuring system as claimed in any one of claims 1-5, wherein the alarm module comprises a warning light and a buzzer.

9. A rail wagon weighing and measuring system as claimed in any one of claims 1-5, wherein the power supply module comprises a DC stabilized power supply for converting 220V AC mains power into 3V, 5V, 12V DC voltage.

10. A rail wagon weighing and measuring system as claimed in any one of claims 1-5, wherein the signal processing module adopts an integrated high-precision analog-to-digital converter, and comprises an amplifying circuit and an analog-to-digital conversion circuit which are connected with each other, and a voltage-stabilized power supply and a clock oscillator which are connected with the amplifying circuit and the analog-to-digital conversion circuit.