JP2000097724A - Impact recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an impact recorder capable of correcting an acceleration sensor having no difference of actually received acceleration without necessity of a large scale apparatus at any necessary time without decomposing the recorder or the like. SOLUTION: Acceleration data input from an A-D converter 21 is recorded in a recording unit 23, and input to a comparator 31. The comparator 31 compares the input acceleration data with a value of a maximum value work 32 and a value of a minimum value work 35, and judges whether it is larger than the work 34 or smaller than the work 35. If the data is larger than the maximum value or smaller than the minimum value, an amendment in which the maximum value recorded in a maximum value recording area 32 or the minimum value recorded in a minimum value recording area 33 in a recorder 24, the value of the work 34 and the value of the work 35 are rewritten and calculated is received by the impact recorder via a communication unit 24, and the value is stored in a nonvolatile memory 25.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an impact recorder for measuring and recording an acceleration applied to an article by various operations.

[0002]

2. Description of the Related Art When an article is handled or transported, the article may be damaged by an impact due to a drop, collision, or bounce. When damaged, it is necessary to clarify at what point of impact, such as during handling and transportation, the damage. Since an item is subject to acceleration when subjected to an impact, measuring and recording the acceleration in chronological order makes it clear at which point of impact during handling and transport, it is possible to grasp the cause of damage. it can. Such an impact recorder (acceleration recorder) is used by being attached to an article, receiving the same handling and transportation as the article, measuring the generated acceleration, recording, handling, transporting, and then storing it in the impact recorder. Read the stored records to determine the impact that the item may have received. A personal computer or the like is used for reading the record.

[0003] For example, the impact detector of Japanese Patent No. 2666926 senses physical variables of physical changes that an article undergoes during handling operations such as packaging and shipping, and satisfies predetermined criteria. In an acceleration detecting method for recording a time history portion of the sensed physical variable, (a)
An acceleration in a range of ± 256 g due to a physical change in the X, Y, and Z axis directions is detected, and 0 corresponding to the detected acceleration is detected.
A program that stores an acceleration detection means, a clock means, a storage means, a communication means, a microprocessor means and a power supply for outputting an electric signal in a range of from 5.12 volts to a housing, and constitutes an instruction to the microprocessor means The acceleration is detected under the control of (1) and quantified, and the detected and quantified acceleration and the time when the acceleration is detected are stored in the storage unit, and the acceleration is detected by the acceleration detection unit. Attaching the housing to the article such that the applied acceleration is physically approximately equal to the article, and (b) subjecting the article to a handling operation such that the housing receives the same acceleration as the article; (C) detecting the acceleration exerted by the housing, and (d) detecting the acceleration that satisfies the predetermined criteria. Storing each time interval over time in said storage means, wherein said time interval is of a predetermined duration, and each said duration initially starts with an acceleration that satisfies said criterion; And
(E) The stored acceleration is read out from the storage means to a device outside the housing, and thereby, while the article is being handled, the magnitude of the acceleration, its occurrence time and occurrence frequency are determined by the article handling. Acceleration measurement method determined after execution. An acceleration detection / recording device that can be stored in the housing, wherein acceleration detection means for detecting acceleration due to a physical change in the X, Y, and Z directions and generating a quantified digital signal of the detected acceleration; Storage means for storing program instructions and data representing the digital signal; communication means for communicating with the separator by the digital information; and the acceleration detection means, clock means, storage means and communication means To read and execute the program instruction from the storage means, and to store the digital signal generated by the acceleration detection means and the storage means in the storage means during a time interval of a predetermined duration. Data representing both a digital timer signal generated by the clock means at the beginning of the duration Microprocessor means for controlling said communication means to start said time interval when at least one of said accelerations meets a predetermined criterion and to communicate with said separator by said digital information. The acceleration detection recording device provided with. Etc. are described.

In the shock storage unit disclosed in Japanese Patent No. 2719580, a processing module box having a built-in operation storage means for calculating and storing shock information from a shock detection signal and a sensor module box having a built-in shock sensor are separated. And a shock storage unit configured to supply a shock detection signal obtained from the sensor module box to the processing module box via a signal transmission medium, wherein the shock detection signal is an electric signal as the signal transmission medium. Using a signal transmission cable that transmits as
The signal transmission cable is connected to one or both of the sensor module box and the processing module box via a detachable connector, and further converts a shock wave signal output from the shock sensor into a voltage or current signal in the sensor module box. A signal converter for amplification is built in, and a battery for supplying power to the arithmetic storage means is built in the other processing module box, and the power of the battery is supplied to the signal converter in the sensor module box through the signal transmission cable. A shock memory unit characterized in that the shock memory unit is designed to be used. Is described.

[0005] Further, the shock data recording method and the shock data recording card for dropping a conveyed product disclosed in Japanese Patent Application Laid-Open No. 8-62240 collect and record the shock data received by the transported luggage L during transportation. A shock data recording card for detecting and storing a shock on the baggage L and transporting the card. After the transportation, the shock data recording card is loaded into a data display device to transfer the shock data. A method of recording impact data such as a drop of a transported product, characterized by obtaining a graph. In a housing formed in a card shape having a predetermined shape and a predetermined thickness, such as a rectangular shape, a small and thin impact detection sensor and an impact history recording means for storing a gravitational acceleration G value by an output in association with time are provided. A card for recording impact data, comprising: The G value memory is normally a memory for a fixed time, such as every minute, and stores a G value and a time in real time when a large G value of a predetermined value or more such as 10 G or more is input. An impact data recording card, characterized in that: And so on.

[0006] These impact recorders use sensors for detecting impacts, most of which detect impacts as acceleration, and obtain the impact applied to an article or the like from the acceleration. The accelerometer used reads the voltage output from the accelerometer, converts it to acceleration, in order to generate a voltage in proportion to the applied acceleration.
Find the acceleration, or shock. Naturally, the acceleration sensors used have individual variations, and to determine the acceleration, the voltage output from the acceleration sensor must be
A correction must be made to determine the acceleration. If an accurate acceleration (shock) is to be obtained, the numerical value (correction value) and correction method used for this correction are important, and the correction value is a numerical value that must be set for each shock recorder.

Conventionally, such correction of the sensor characteristics is performed by:
First, the method of measuring the characteristics of the acceleration sensor alone and determining the correction value based on the characteristics, or the method of measuring the output of the sensor in the semi-finished state of the impact recorder and determining the correction value based on the result are taken. I have. The correction value is set by a resistor, a volume, and the like, and corrects the output of the acceleration sensor so that the acceleration sensor outputs a voltage in accordance with a predetermined proportional relationship.

Further, these impact recorders need to have a structure that can withstand an impact depending on the purpose of use, and a structure that cannot be easily disassembled or the like is desired. Therefore, it is difficult to realize a structure in which an impact is directly applied to the acceleration sensor, and a method is used in which an impact applied to a case or the like is transmitted to the sensor via the case or the like and acceleration is detected.

[0009]

However, in the method of measuring the characteristics of the acceleration sensor alone and determining the correction value based on the characteristics, the acceleration and the acceleration applied to the case and the like due to the difference in the mounting method to the case and the like. Differences in sensor output cannot be corrected. In other words, there is a difference between the acceleration actually received by the shock recorder and the detected acceleration.

Further, in the method of measuring the output of the sensor in a semi-finished state of the impact recorder and determining the correction value based on the result, the measurement must be performed while applying the acceleration. Therefore, the output of the acceleration sensor with respect to the acceleration changes due to noise from the device and the like, noise due to wiring and the like, and a measurement value error, and correction cannot be performed properly.

Further, in order to correct the deterioration of the characteristics due to the temporal change of the acceleration sensor, the shock recorder must be disassembled or the like, and a structure not suitable for the intended use of the shock recorder must be taken. No.

The present invention solves the above-mentioned problems, and attaches a sensor or the like to an impact recorder, completes the assembly, does not disassemble the impact recorder, does not require a large-scale device whenever necessary, Provided is an impact recorder that enables an acceleration sensor to be corrected without a difference from an actually received acceleration.

[0013]

SUMMARY OF THE INVENTION In an impact recorder for measuring and recording acceleration applied to an article by various operations, a function of detecting a maximum value and a minimum value of an applied acceleration, an electrically rewritable nonvolatile memory The maximum value obtained when a certain acceleration is applied, the maximum value obtained from the minimum value detection function, and the maximum value obtained when no acceleration is applied, the minimum value detection function From the minimum value obtained from, the characteristics of the acceleration detection sensor are obtained, the correction value of the acceleration detection sensor with respect to the applied acceleration is calculated, and the correction value is stored in an electrically rewritable non-volatile memory. It is assumed that the impact recorder obtains the acceleration from the output value obtained from the detection sensor and the correction value stored in the electrically rewritable nonvolatile memory.

In a shock recorder that measures and records the acceleration applied to an article by various operations, a function for detecting a maximum value and a minimum value of an applied acceleration, a maximum value obtained from a maximum value and a minimum value detection function of an acceleration. A function of recording values and minimum values, a function of transmitting the stored maximum values and minimum values by communication, a function of receiving correction values by communication, an electrically rewritable nonvolatile memory, The impact recorder has a function of rewriting a correction value stored in a rewritable nonvolatile memory to a received correction value, and rewrites the correction value by communication after applying a predetermined acceleration.

An impact recorder for measuring and recording an acceleration applied to an article by various operations has a function of detecting a maximum value and a minimum value of an applied acceleration, an electrically rewritable nonvolatile memory, The calculation of the correction value and the storage of the correction value in an electrically rewritable non-volatile memory are performed by applying a predetermined acceleration in a predetermined pattern to detect the maximum value and the minimum value. A shock recorder that automatically calculates the correction value of the acceleration detection sensor from the maximum value and the minimum value from the function and automatically stores the correction value in an electrically rewritable nonvolatile memory.

[0016]

FIG. 1 is a block diagram illustrating the present invention. The shock recorder comprises a sensor section 1, a processing circuit section 2, and a power supply section 3, and can measure and record with the shock recorder alone. The sensor unit 1 includes an acceleration sensor and a detection circuit, and the power supply unit 3 is a battery. The processing circuit unit 2 includes an AD conversion unit, a nonvolatile memory unit, a recording unit, a communication unit, and the like, and details will be described in the following embodiments.

FIG. 2 is a block diagram showing a first embodiment of the present invention. The acceleration detected by the sensor unit 1 that detects the acceleration is converted into a voltage and input to the AD conversion unit 21.
The AD converter 21 converts the input voltage into a digital signal and outputs the digital signal to the CPU 22. The CPU 22 captures the converted digital signal, that is, the acceleration data, and records it in the recording unit 23. The acceleration data recorded in the recording unit 23 is read from the communication unit 24 as necessary. Communication unit 2
4 is capable of transmitting data as well as receiving data, and can receive conditions to be recorded in the recording unit 23, such as time conditions, and setting information of the main body of the shock recorder, such as clock setting information. The CPU 22 receives the recording conditions,
The shock recorder is operated according to the setting information of the shock recorder main body. The nonvolatile memory unit 25 is connected to the CPU 22. The nonvolatile memory unit 25 used here uses an electrically erasable EEPROM.

FIG. 3 shows a first embodiment of the present invention.
FIG. 4 is a block diagram showing the operation of calculating a correction value in FIG. 3. All the functions in FIG. 3 are built in the main body of the shock recorder. A
The acceleration data input from the D conversion unit 21 is stored in the recording unit 2
3 and input to the comparator 31. In the comparator 31, the input acceleration data and the maximum value work 3
4 is compared with the value of the minimum work 35, and is larger than the value of the maximum work 34 or the minimum work 35.
Is smaller than the value of. If it is larger than the maximum value or smaller than the minimum value, the maximum value recorded in the maximum value recording area 32 in the recording section 24 or the minimum value recorded in the minimum value recording area 33 and the maximum value work 34 Or the value of the minimum work 35 is rewritten. Thereafter, every time acceleration data is input to the CPU 22, the operation of rewriting the maximum value and the minimum value is performed. During this maximum and minimum value rewriting operation, a certain acceleration is applied, and the recording is accumulated and the maximum and minimum values are detected without applying any acceleration. The operation of detecting the maximum value and the minimum value is performed simultaneously with the normal detection operation, that is, the operation of detecting and recording acceleration. After the application of the predetermined acceleration is completed, the personal computer or the like transmits the communication unit 24 to the recording unit 2.
3, the maximum value recorded in the maximum value recording area 32,
Alternatively, the minimum value recorded in the minimum value recording area 33 is read. A correction value is calculated from the applied acceleration and the read maximum value and minimum value. The calculated correction value is received by the shock recorder via the communication unit 24, and the value is stored in the nonvolatile memory 25.

Next, a method of calculating the correction value will be described by way of example. Normally, an AD converter 21 having a resolution of 8 bits to 12 bits is used, but in the present description, 10 bits will be described. It is assumed that the maximum value of the acceleration applied during the operation of detecting the maximum value and the minimum value is 50G. If the maximum value and the minimum value obtained at that time were 550 and 50, respectively, the maximum value 550 is a value obtained when the acceleration 50G was applied, and when the minimum value 50 or the acceleration was not applied, That is, the value obtained when the acceleration is 0 G. Since the acceleration applied as a characteristic of the acceleration sensor and the output voltage are in a proportional relation, the constant A indicating the slope of the proportional relation is A =
(50-0) / (550-50) = 0.1 A constant B indicating a contact piece having a proportional relationship is B = 50−0.1 × 550 = −5.
Becomes A and B are correction values of the acceleration sensor, and are values stored in the nonvolatile memory 25.

When the acceleration data recorded in the recording unit 23 is read out via the communication unit 24, this acceleration value is used
The acceleration data recorded in the recording unit 23, that is, the acceleration data as input from the AD conversion unit 21, is corrected and output. The correction method uses the constants A and B,
If the data recorded in the storage unit 23 is D,
The corrected acceleration G is obtained by G = A × D + B.
In this example, when the acceleration data recorded in the recording unit 23 is read out via the communication unit 24, the acceleration data is corrected. However, if the correction value is predetermined and stored in the nonvolatile memory 25 in advance, For example, it is also possible to make a correction when the acceleration data is input from the AD conversion unit 21 and record the corrected data (data converted into acceleration) in the recording unit 23.

The operation of detecting the minimum value and the maximum value, rewriting of the correction value by communication, conversion into acceleration, and the like can be easily realized by using a microprocessor. Since the correction value is stored in the non-volatile memory 25, the correction value will not be lost even when the power is not supplied, such as when the battery is exhausted. The nonvolatile memory unit 25 is an electrically rewritable EEPROM.
Since M is used, the correction value can be rewritten many times. This allows you to attach the acceleration sensor,
After completion, the sensor can be corrected. This means that the correction is made by the acceleration applied to the case or the like, in other words, there is no difference from the actually received acceleration, and the correction can be made without disassembling or the like. Further, a large-scale device is not required at the time of determining the correction value, and only the shock recorder can determine the correction value.

In this embodiment, the calculation of the correction value is not built in the recorder main body. However, it can be built in. For example, the calculated correction value is read by communication and confirmed.
Rewriting or changing the operation of the main body of the shock recorder by communication, and calculating and rewriting the correction value only during the operation can be easily realized.

Further, by applying a predetermined acceleration in a predetermined pattern, a correction value can be calculated and rewritten only in a certain specific state.

An embodiment in which a correction value is calculated and rewritten only in a specific state by applying a predetermined acceleration in a predetermined pattern will be described. The acceleration to be applied and the application pattern of the acceleration when the correction value is to be calculated and rewritten are to be determined. For example, the acceleration to be applied is set to 1 in steps of 10G.
It increases every minute, and when it reaches 100G, it decreases every minute in 10G steps. That is, 10G is 1
For 20 minutes, followed by 20G for 1 minute, 30G for 1 minute,
40G for 1 minute, 50G for 1 minute, 60G for 1 minute, 7
0G for 1 minute, 80G for 1 minute, 90G for 1 minute, 10G
0G was applied for 1 minute, followed by 90G for 1 minute, 80G for 1 minute, 70G for 1 minute, 60G for 1 minute, 50G for 1 minute, 40G for 1 minute, 30G for 1 minute, and 20G for 1 minute. For 10 minutes and 10 G for 1 minute. A function of judging this acceleration application pattern is also provided in the main body of the shock recorder. If acceleration is applied by this acceleration application pattern, a correction value is calculated and a rewriting operation is performed.

The acceleration applied in a constant pattern as in the example cannot be seen in normal use, so that it can be easily determined in the main body of the shock recorder. Since the applied acceleration is predetermined, the maximum value, The applied acceleration with respect to the minimum value is known, and the correction value can be easily calculated.
In other words, the certain acceleration application pattern needs to be an acceleration application pattern that cannot be seen in normal use.

Thus, the correction value can be calculated and rewritten only by applying the acceleration in a constant acceleration application pattern without performing communication.

[0027]

According to the present invention, after the acceleration sensor is mounted and completed, the acceleration can be corrected, so that it is possible to detect the acceleration which is not different from the actually received acceleration, and the characteristics of the acceleration sensor and the acceleration sensor mounting Accurate acceleration can be detected regardless of the state.

Since the correction can be made in the completed state, the correction can be made whenever necessary without disassembling the shock recorder.

Since the shock recorder can be corrected in a completed state,
The correction can be easily realized without requiring a large-scale device.

Since the electrically rewritable nonvolatile memory is used, protection of the correction value can be easily realized.

Since an electrically rewritable nonvolatile memory is used, the correction value can be rewritten as many times as necessary.

Correction can be automatically performed by applying acceleration in a constant acceleration application pattern, so that the correction value can be calculated and rewritten only with the shock recorder.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating the present invention.

FIG. 2 is a block diagram showing a first embodiment of the present invention.

FIG. 3 is a block diagram illustrating an operation of calculating a correction value in a CPU according to the first embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sensor part 2 Processing circuit part 3 Power supply part 21 AD conversion part 22 CPU 23 Recording part 24 Communication part 25 Non-volatile memory part 31 Comparator 32 Maximum value recording area 33 Minimum value recording area 34 Maximum value work 35 Minimum value work

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masaki Shiozawa 4107 Miyota, Miyoda-cho, Kitasaku-gun, Nagano Prefecture F5 term in Miyota Co., Ltd. 2F073 AA40 EF05 EF09 FG01 FG02 FG04 FG04 2F075 AA01 EE15 EE18

Claims (3)

[Claims] An impact recorder for measuring and recording an acceleration applied to an article by various operations has a function of detecting a maximum value and a minimum value of an applied acceleration, and an electrically rewritable nonvolatile memory. The maximum value obtained when a certain acceleration is applied, the maximum value obtained from the minimum value detection function, and the maximum value obtained when no acceleration is applied,
From the minimum value from the minimum value detection function, the characteristics of the acceleration detection sensor are obtained, the correction value of the acceleration detection sensor for the applied acceleration is calculated, and the correction value is stored in an electrically rewritable nonvolatile memory. An impact recorder, wherein acceleration is obtained from an output value obtained from a stored acceleration detection sensor and a correction value stored in an electrically rewritable nonvolatile memory. 2. A function for recording a maximum value and a minimum value obtained from a maximum value and a minimum value detection function of acceleration, a function for transmitting the stored maximum value and minimum value by communication, and a function for transmitting a correction value by communication. Has a function of receiving, and a function of rewriting the correction value stored in the electrically rewritable nonvolatile memory to the received correction value, and after applying a predetermined acceleration,
2. The correction value is rewritten by communication.
Impact recorder as described. 3. A method of recording a shock by recording a correction value and storing the correction value in an electrically rewritable non-volatile memory by applying a predetermined acceleration in a predetermined pattern. 2. The impact recorder according to claim 1, wherein the recording is automatically performed in the vessel.