JP5882849B2 - Electronic equipment installation environment judgment device - Google Patents

Description

  The present invention has a bad installation environment (temperature / humidity) so as not to shorten the expected life of electric / electronic components used in various electronic devices and to prevent the failure rate during the accidental failure period from increasing. If the installation environment is poor (temperature / humidity is high) compared to the installation environment conditions set in advance, an electronic device using a conductive film that issues an alarm to improve the installation environment The present invention relates to an installation environment determination apparatus.

  When a component or the like used for an electric / electronic device fails, the failure occurs in any one of the initial failure period, the accidental failure period, and the wear failure period shown in FIG. In the initial failure period, the failure rate decreases with time, and the failure rate in the market can be reduced by performing burn-in or the like and removing the failure.

  In the accidental failure period, failures occur randomly, and the failure rate is generally almost constant. The wear failure period is a period in which a failure starts as a so-called life (a product that reaches the end of its life begins to appear). The failure rate increases with time.

  As for the failure in the wear failure period, so-called life, there is a method of shortening the life of the part under test by using the one having poor environmental resistance and predicting the remaining life (see Patent Document 1). In order to sense abnormal temperature and humidity, there is a method (see Patent Document 2) in which a temperature sensor and a humidity sensor are installed (mounted) in an electric circuit in the apparatus and temperature and humidity are monitored.

JP 2000-214205 A Japanese Patent No. 3295005

  Failures in the accidental failure period occur randomly and cannot be removed by burn-in. In addition, the failure rate varies greatly depending on the use environment. That is, when used at high temperature and high humidity (humidity), the failure rate during the accidental failure period increases. In addition, the time until the wear failure period is shortened, and the failure rate of parts and the like that should originally have been kept to the product life becomes a problem because the failure rate suddenly increases before the product life. For example, assuming that the product life is 10 years, it is necessary to prevent parts from entering the wear-out failure period for at least 10 years. However, parts that are assumed to be replaced as consumables are excluded. Therefore, it is important not to use at high temperature and high humidity (high temperature and high humidity).

  Note that the time until the wear failure period and the failure rate during the accident failure period (hereinafter referred to as “wear accident reliability”) are estimated on the assumption that the wear failure period was used at a certain temperature and a certain humidity (constant conditions). The Therefore, if the temperature and humidity of the installation environment are higher than the temperature and humidity used for estimation of accidental wear reliability, the time to enter the estimated wear-out failure period is shortened, and the failure rate during the accidental failure period is It will be high. Therefore, it is necessary to know the temperature and humidity of the installation environment, but even if the temperature and humidity that change from moment to moment are measured, the measured temperature and humidity are individually measured against the constant temperature and humidity used for estimation. It is difficult to make a comparison over a certain period of time. In other words, when used for a certain period (three months, half a year, one year, etc.), the usage conditions (temperature / humidity conditions) that change from period to period are constant temperatures used for estimation of accidental wear reliability. It was difficult to judge whether it was good or bad compared with humidity.

  For example, in an environment where the temperature and humidity change greatly, such as in Japan where there are four seasons or the rainy season, the temperature and humidity are not constant. Whether the installation environment falls within the range of the failure rate of the period, and the expected product life (excluding consumables, within the expected period of use (for example, 5 years or 10 years) when used at a certain temperature and a certain humidity) It was difficult to know if the installation environment would be shorter. As an example, the four seasons in Japan are listed. However, in Southeast Asia, the temperature and humidity change, and the reliability changes greatly due to the non-use of the air conditioner. It was difficult to know clearly whether the temperature and humidity used in the test were high or low.

  The technique disclosed in Patent Document 1 only knows the remaining life. It is necessary to replace it before it breaks down. It is not an idea that the assumed life is not shortened, nor is it an idea that the assumed failure rate of the accidental failure period is not increased. In addition, the technique disclosed in Patent Document 2 is intended to detect a failure such as a hole in a sealed container with a temperature / humidity monitor. This is not a technique for monitoring the humidity so as not to shorten the period until the expected wear-out failure period so that the failure rate during the assumed accidental failure period does not increase.

  In view of the above-described problems of the prior art, the present invention determines the environment in which the control device and the electronic device are installed, and affects the components provided in the control device and the electronic device (lifetime is assumed). If the time is shorter or the failure rate of the accidental failure period is higher), an alarm is output according to the impact, and the time until the wear failure period (life) is dealt with by responding to the alarm (improving the environment) It is an object of the present invention to provide an installation environment determination device for an electronic device using a conductive film that can prevent a short period of time and can maintain a failure rate in a random failure period within an assumed range.

  Using conductive films having different resistance value rising speeds corresponding to temperature and humidity, and testing in advance by changing the temperature and humidity as described later, the change of the resistance value with respect to time is examined. Based on the test results, the resistance value of the reference conductive film and the reference time are obtained. In actual use, measure the resistance value of the conductive film every certain time, and when the resistance value reaches the reference value (when it enters the vicinity of the reference value or exceeds the reference value), compare it with the reference time It is possible to determine whether the environment where the control device and electronic equipment are installed is appropriate or not. If this is the case, it is indicated by an alarm. By improving the inappropriate environment to an appropriate state, it is possible to prevent the life from being shortened and to keep the failure rate in the accidental failure period within an assumed range.

  For conductive films with different resistance rise speeds corresponding to temperature and humidity, when thin conductive films, for example transparent conductive films that are thin enough to be used as electrodes for touch panels, are formed on plastic films, the structure and film quality, etc. Some are vulnerable to high temperature and high humidity (high temperature and high humidity) (for example, the resistance value increases). To improve the reliability, the technology to provide a barrier layer on the plastic film or to make a multilayer structure, and to reduce the difference in thermal expansion coefficient For example, a technique for providing a layer for heat treatment, a technique for crystallizing an amorphous conductive film by heat treatment, and a technique focusing on carbon.

  As is clear from these, the resistance value increases depending on the temperature and humidity conditions (high temperature and high humidity) depending on the structure and film quality of the thin conductive film. The present invention is not about a conductive film that is resistant to temperature and humidity (a conductive film whose resistance value is almost constant even when the temperature and humidity are high, since transparency is not necessary in the present invention, it is simply a conductive film) Conversely, a conductive film whose resistance value increases when temperature and humidity are high is used.

  The present invention uses a conductive film having a property of increasing resistance under high temperature and high humidity (high temperature and high humidity), and has a structure in which moisture (water vapor) in the air can enter (that is, ceramic or the like). By using a material that does not allow moisture (water vapor) in the air to penetrate into all surfaces, a sealed structure is not used), and the resistance value increases with time due to temperature and humidity.

As the material for the conductive film, metal thin films such as gold, silver, and palladium, and metal oxides such as indium oxide, tin oxide, indium-tin oxide (ITO), and zinc oxide (ZnO) can be used. Since the invention does not require transparency, it is not limited to these metal thin films and metal oxides.
A vacuum deposition method, a sputtering method, or the like can be used for forming the conductive film. In the present invention, the film quality of the conductive film is preferably amorphous rather than crystalline. The amorphous and crystalline film forming temperature is almost amorphous when the substrate temperature is 100 ° C. or lower, and 150 ° C. or higher is necessary to obtain a crystalline material.

  Polyethylene terephthalate (PET), polyimide, polycarbonate, acrylic, polyethylene, etc. can be used as a base material for forming a conductive film, but in the present invention, it is not necessary to be transparent. Can be used about. In addition, the base material on which the conductive film is formed is not limited to plastic, but may be any insulating base material. For example, ceramic or glass can be used. When ceramic or glass is used as a base material, it is necessary for moisture in the air to enter from at least one of the conductive films. For example, when a conductive film is formed on ceramic, moisture in the air will not enter if sealed with ceramic, so the surface of the conductive film should be protected as a water vapor permeable insulator and a moisture permeable coating material. It is necessary to allow moisture in the air to enter, such as without protection (exposing the surface to the outside).

The invention according to claim 1 of the present gun is provided in the electronic device, wherein a determined installation environment determination apparatus installation environment of the electronic device, a conductive film provided on the circuit within the electronic apparatus, wherein A measurement unit that measures the resistance value of the conductive film at predetermined time intervals or at predetermined timings, and stores the resistance value measured by the measurement unit in association with an elapsed time from the start of use or an elapsed time from the manufacture. A measured value storage unit, a reference time storage unit that stores the relationship between the resistance value of the conductive film at a reference temperature / humidity and the elapsed time used as the reference time, and the measured resistance value becomes a predetermined resistance value. a comparator for comparing the elapsed time in the elapsed time and the reference time when the said comparison unit comparing the result of, the continued use temperature and humidity of the installation environment of the electronic device, wear failure of the electronic apparatus In the installation environment determination apparatus of an electronic device and having a comparison result output unit for outputting an alarm in response to the short become degree when the it is determined that is shorter than the supposed number of years to between (life) is there.
An invention according to claim 2 is an installation environment determination device that is provided in an electronic device and determines an installation environment of the electronic device, the conductive film provided on a circuit in the electronic device, and the conductive film A measurement unit that measures resistance values at predetermined time intervals or at predetermined timings, a measurement value storage unit that stores resistance values measured by the measurement units in association with measurement times, and a conductive film at a reference temperature / humidity The reference time storage unit that stores the relationship between the resistance value of the sensor and the elapsed time used as the reference time, and the elapsed time from the start of use calculated from the measurement time when the measured resistance value becomes a predetermined resistance value a comparator for comparing the elapsed time in the elapsed time and the reference time from the time or the time of production, comparison result from the comparison unit, the continued use temperature and humidity of the installation environment of the electronic device, the electronic Installation of an electronic device characterized by having a comparison result output unit for outputting an alarm in response to the short become degree when it is determined that is shorter than the supposed number of years to wear-out failure period vessels (life) It is an environmental judgment device.
An invention according to claim 3 is an installation environment determination device that is provided in an electronic device and determines an installation environment of the electronic device, the conductive film provided on a circuit in the electronic device, and the conductive film A measurement unit that measures resistance values at predetermined time intervals or at predetermined timings, and a measurement value storage that stores resistance values measured by the measurement units in association with elapsed time from the start of use or elapsed time from manufacturing And a reference time storage unit that stores the relationship between the resistance value of the conductive film at a reference temperature / humidity and the elapsed time used as a reference time, and when the measured resistance value becomes a predetermined resistance value, From a resistance value stored in the measurement value storage unit and a measurement ratio calculation unit that calculates a measurement ratio between an increase in elapsed time and an increase in resistance value from the elapsed time, and from the resistance value and elapsed time stored in the reference time storage unit Calculated elapsed time A reference ratio calculating unit for calculating a reference ratio of the increment of the incremental resistance value of a comparator unit for comparing the measured ratio with the reference ratio and the calculated, comparison by the comparison unit result, installation environment of the electronic apparatus A comparison result output unit that outputs an alarm according to the degree of shortening when it is determined that the use is continued at a temperature / humidity of less than the expected number of years until the wear-out failure period (life) of the electronic device. to have a installation environment determination device for electronic apparatus characterized.

The invention according to claim 4 is an installation environment determination device that is provided in an electronic device and determines an installation environment of the electronic device, the conductive film provided on a circuit in the electronic device, and the conductive film A measurement unit that measures resistance values at predetermined time intervals or at predetermined timings, a measurement value storage unit that stores resistance values measured by the measurement units in association with measurement times, and a conductive film at a reference temperature / humidity A reference time storage unit that stores the relationship between the resistance value of the current and the elapsed time used as the reference time, and the resistance value and time stored in the measurement value storage unit when the measured resistance value becomes a predetermined resistance value. A measurement ratio calculation unit that calculates a measurement ratio between an increase in elapsed time and an increase in resistance value from, a resistance value stored in the reference time storage unit, an increase in elapsed time calculated from the elapsed time, and an increase in resistance value Criteria for calculating the reference ratio A calculation unit, a comparing unit for comparing the measured ratio with the reference ratio and the calculated comparison result by the comparison unit, the continued use temperature and humidity of the installation environment of the electronic device, wear failure of the electronic apparatus in the installation environment determination apparatus of an electronic device and having a comparison result output unit for outputting an alarm in response to the short become degree when the it is determined that is shorter than the supposed number of years to a period (lifetime) is there.
The invention according to claim 5 is characterized in that the comparison result output unit is configured such that an elapsed time when the predetermined resistance value is reached is shorter than the reference time, or an elapsed time when the predetermined resistance value is reached. 5. The electronic device installation environment determining apparatus according to claim 1, wherein an alarm is output when a difference from the reference time is within a predetermined range. 6.
The invention according to claim 6 is provided with a plurality of the reference times, and an alarm corresponding to a reference time closest to the reference time among the plurality of reference times when the comparison result output unit reaches the predetermined resistance value or The electronic device installation environment determining apparatus according to claim 1, wherein a message is output.

  According to the present invention, the environment in which the control device or the electronic device is installed is determined, and the components provided in the control device or the electronic device are affected (the life is shorter than expected or the failure in the accidental failure period) If the rate is high), an alarm according to the impact is output and the alarm is dealt with (improves the environment) to prevent the time until the wear failure period (life) from being shortened. It is possible to provide an installation environment determination device for an electronic device using a conductive film capable of keeping a failure rate within an assumed range.

In the initial failure period, the failure rate decreases with time, in the accidental failure period, the failure rate is almost constant, in the wear failure period, the failure rate increases with time, and when a failure occurs, it is one of these three It is a figure explaining this. Describes a structure consisting of a conductive film whose resistance increases with the passage of time and a conductor (electrode) formed on both sides connected to the conductive film on an insulating base material having water vapor permeability. It is a figure to do. An insulating base material that does not have water vapor permeability has a structure consisting of a conductive film whose resistance value increases over time corresponding to temperature and humidity, and a conductor (electrode) formed on both sides connected to the conductive film. It is a figure explaining. It is a figure explaining the example which shape | molded the electrically conductive film which resistance value rises with temperature and humidity between the conductor patterns on a board | substrate (a printed circuit board, an alumina substrate, etc.). It is a figure explaining the relationship between time and resistance value in a conductive film. It is a figure explaining the graph plotted on the graph of the Weibull distribution about the case where resistance value is R1. It is a figure explaining the relationship which becomes the set accumulation percentage, and "1 / temperature". It is a figure explaining the relationship which becomes the set accumulation percentage, and "1 / humidity." It is a figure explaining the relationship between the value calculated | required by substituting temperature and humidity to ((E / k (T + 273)) + ((beta) / RH)), and time. It is a figure explaining the relationship between the value calculated | required by substituting the temperature and humidity of environmental conditions 1-3 for ((E / k (T + 273)) + ((beta) / RH)), and time. It is a figure explaining the relationship between the value calculated | required by substituting the temperature and humidity of environmental conditions 1-3 about (R / Rn) for ((E / k (T + 273)) + ((beta) / RH)) about R1-Rn. The value of ((E / k (T + 273)) + (β / RH)) is obtained from Tm_Rx (x is 1 to n), and the obtained value and installation conditions 1 to 3 ((E / k (T + 273)) It is a figure explaining the relationship with the value of + ((beta) / RH). It is a figure explaining embodiment of this invention provided with the resistance value measurement part, the comparison (judgment) part, the memory | storage part, and the alarm output part. It is a figure explaining embodiment of this invention provided with the resistance value measurement part, the calculation and comparison (judgment) part, the memory | storage part, and the alarm output part. It is a figure which shows the electrically conductive film from which resistance value rises with time corresponding to the temperature and humidity provided on the locker. It is a figure which shows the electrically conductive film which resistance value rises with time corresponding to the temperature and humidity provided in the inner surface of the locker. It is a figure explaining the electrically conductive film which resistance value rises with time corresponding to the temperature and humidity provided in the printed circuit board.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<Conductive Film Used in Embodiment of the Present Invention>
When the temperature and humidity are low, the resistance value of the conductive film used in the embodiment of the present invention (for example, an ITO film of an amorphous type) does not readily increase. If the temperature / humidity (temperature and humidity) is high, the resistance value will increase rapidly (note that the increased value will not decrease). The present invention utilizes this property and monitors the increase in the resistance value of the conductive film at certain intervals. If the increase in resistance value is faster than the increase in resistance value at the reference temperature and humidity, the temperature and humidity The alarm is output because there is a problem with high reliability. By responding to the alarm, it is possible to prevent the life from becoming shorter than the expected life and to prevent an increase in the failure rate during the accidental failure period.

The conductive film used in the embodiment of the present invention can be used as an element having a structure as described below or directly formed on a printed circuit board.
As shown in FIG. 2, a conductive film 5 (for example, an ITO film) whose resistance value increases over time corresponding to temperature and humidity, and a conductive film 5 are formed on an insulating base material 4 having water vapor permeability. And conductors (electrodes 6 and 6) formed on both sides connected to each other. In this case, the surface of the conductive film 5 may be exposed to the outside, or the conductive film 5 may be covered with an insulating material having a water vapor permeability as a coating material for the moisture permeable layer, or an insulating material having no water vapor permeability. The surface of the conductive film 5 may be covered with an object. As an insulating base material having water vapor permeability, it refers to plastics in general, but has water vapor permeability (20 to 30 g / m ² · 24 h, 40 ° C., 90% RH at a PET film thickness of 25 μm) of about PET or more. Plastic is preferred.

  The element shown in FIG. 3 includes a conductive film 5 (for example, an ITO film) whose resistance value increases over time corresponding to temperature and humidity on an insulating base material 7 (for example, ceramic, glass, etc.) that does not have water vapor permeability. ) And conductors (electrodes 6 and 6) formed on both sides connected to the conductive film 5. In this case, the surface of the conductive film 5 may be exposed to the outside, or the surface of the conductive film 5 may be covered with an insulating material having water vapor permeability as a coating material for the moisture permeable layer. The insulating base material having water vapor permeability refers to all plastics, but plastic having water vapor permeability higher than that of PET is preferable. Further, the hole diameter and the number of holes, that is, the hole area may be changed in the covering material of the conductive film 5 portion. Further, a slit may be formed in the covering material of the conductive film 5 so that moisture in the air can easily reach the conductive film 5.

  Next, the conductive film 5 whose resistance value increases with time in accordance with temperature and humidity will be described. The conductive film 5 is formed by a sputtering method. The film thickness is preferably about 5 to 200 nm. The temperature is preferably 100 ° C. or lower, and is preferably amorphous. Note that if the resistance value rises too much due to the elapsed time corresponding to the temperature and humidity, a barrier layer is provided, heat is applied to crystallize the amorphous state, or water vapor is generated in an insulator having water vapor permeability. The speed of increase in resistance value can be adjusted by making it difficult to transmit. When the barrier layer is insufficient or the ITO film is not sufficiently crystallized, the rising speed of the resistance value of the ITO film varies depending on the temperature and humidity conditions, so calculate the increased resistance value and time. Thus, it is possible to estimate whether the temperature and humidity are in a range where there is no problem in reliability.

  As shown in FIG. 4, the conductive film 5 whose resistance value increases between the conductor patterns (between the wiring patterns 9 and 9) on the substrate (printed substrate, alumina substrate, etc.) due to the temperature and humidity in FIG. May be formed. The presence / absence and protection of the protective film of the conductive film 5 are as described above.

<Embodiment of a numerical control device provided with an installation environment determination device using a conductive film whose resistance value increases with elapsed time corresponding to temperature and humidity>
A numerical controller built in the computer controls the machine tool. Machine tools are installed in adverse environments (for example, buildings that are not air-conditioned, have high temperatures in the summer, and high humidity during the rainy season, and facilities that are affected by high temperatures in the surroundings). Sometimes. If it continues to be used while installed in an adverse environment, the failure rate of the numerical control device will be higher than expected, and the lifetime will be shorter than expected.

In order to prevent this, it is necessary to know in which environment the numerical control device is installed and used. Some alarms are issued when the temperature and humidity during use exceed a certain value, but the temperature and humidity in that setting are generally high, so it is aged at a temperature and humidity close to that setting. If the product is used continuously, the service life may be shortened or the failure rate during the accidental failure period may be increased.
In view of this, the embodiment described below allows the user to know over time whether the battery is being used at an appropriate temperature and humidity.

  An embodiment in the case where an installation environment determination device using a conductive film whose resistance value increases with the passage of time corresponding to temperature and humidity is provided, for example, in a numerical control device is as follows. FIG. 13 shows a circuit configuration in the embodiment of the present invention. The resistance value measurement / comparison (determination) / memory / alarm output circuit 50 includes a resistance value measurement unit 51, a comparison (determination) unit 54, a storage unit 55, and an alarm output unit 56.

  First, data stored in the storage unit 55 will be described. For example, the resistance value of the ITO film as the conductive film changes as shown in FIG. By performing a test with a certain number of samples at a certain temperature and humidity condition (for example, 60 ° C / 95% or 50 ° C / 95%), time (logarithmic axis) and resistance value (logarithmic axis or logarithmic / logarithmic axis) Logarithm, logarithm, logarithmic axis, etc.) are required.

  Test conditions (1) to (4) represent examples of results for a certain number of samples (the number of samples is n in FIG. 5). The test conditions of temperature and humidity are as follows: test condition (1) is T1 ° C., φ1% RH, test condition (2) is T1 ° C., φ2% RH, test condition (3) is T2 ° C., φ1% RH, test condition ( 4) is assumed to be T2 ° C. and φ2% RH. The relationship between the temperature / humidity and the time taken to increase to a certain resistance value is expressed by equation (1) or equation (2). Here, an example in the case where the formula 1 is applied will be described.

  In Equation 1, when the humidity is constant, the time of the test result at the temperature T1 (° C.) until reaching a certain resistance value is L1, and the time of the test result at the temperature T2 (° C.) is L2 (T1> Assuming that T2 and L1 <L2), the activation energy E is obtained by the equation (3).

  Similarly, when the temperature is constant, the test result time at the humidity φ1 (% RH) until the resistance value reaches a certain resistance value is L1, and the test result time at the humidity φ2 (% RH) is L2 (φ1> φ2 , L1 <L2), the acceleration β is obtained by the equation (4).

  That is, at least 2 conditions for temperature and 2 conditions for humidity (for example, (Tp, φm), (Tq, φm), and (Tq, φn) are used as test conditions). Then, the activation energy E and the acceleration β can be obtained by obtaining two temperatures and the minimum two humidity when the temperature is constant. However, in order to obtain more accurately, it is desirable that the temperature condition is 3 or more and the humidity is 3 or more.

  If the activation energy E and the acceleration β are known, the constant A can be obtained.

  Now, a case where the activation energy E, the acceleration β, and the constant A are obtained by performing a test and plotting on a graph will be described. As described above, the temperature of 3 conditions or more and the humidity of 3 conditions or more are desirable, but for the sake of simplicity, the case of the temperature 2 condition and the humidity 2 condition will be described. The test is performed under four conditions of T1 ° C., T2 ° C. (T1> T2) as temperature conditions, and φ1% RH and φ2% RH (φ1> φ2) as humidity two conditions. That is, test condition (1) (T1 ° C., φ1% RH), test condition (2) (T1 ° C., φ2% RH), test condition (3) (T2 ° C., φ1% RH), test condition (4) (T2 The test is performed under four test conditions of [° C., φ2% RH]. The number of samples is n. These samples are tested under each test condition (test condition (1), test condition (2), test condition (3), test condition (4)).

The resistance value of the conductive film is measured every time and plotted as shown in FIG. By taking the logarithm of the time axis and the resistance axis, the relationship between time and resistance is made to be a straight line. Temperature and humidity are the test conditions (1) (T1 ° C., φ1% RH), test conditions (2) (T1 ° C., φ2% RH), test conditions (3) (T2 ° C., φ1% RH), test conditions ( 4) (T2 ° C., φ2% RH). In FIG. 5, the results of all samples are represented by a belt-like straight line. The resistance values in FIG. 5 are divided into R1 to Rn.
First, the case where the resistance is R1 will be described. The time when the resistance of each sample of T1 ° C. and φ1% RH in the temperature / humidity test condition (1) is R1 is read and plotted on a graph of Weibull probability as shown in FIG. The other three test conditions are also plotted on the Weibull probability graph and represented by a straight line. Reference numeral 22 in FIG. 5 is converted into a straight line indicated by reference numeral 32 in FIG. 6, reference numeral 24 in FIG. 5 is converted into a straight line indicated by reference numeral 34 in FIG. 6, and reference numeral 26 in FIG. 5 is converted into a straight line of reference numeral 38 in FIG. The Weibull plot is publicly known.

From this, the time when the resistance value becomes R1 and the cumulative percentage (%) (F (t)) are the test conditions (test condition (1), test condition (2), test condition (3), test condition (4)). I understand. When the cumulative percentage (%) is selected as x% (x is arbitrary) as shown in FIG. 6, the time under each test condition can be obtained. T ₁₂ cumulative x (%) and becomes time T1 ° C. and .phi.1% RH test conditions (1) at t _11, T1 ° C. and .phi.2% RH test conditions (2) until the R1 in FIG. 6, T2 Let t _{21 be} the test condition (3) at 0 ° C. and φ1% RH, and t ₂₂ be the test condition (4) at T2 ° C. and φ2% RH.

  FIG. 7 is a plot of these times in a graph of “1 / temperature” versus time. Here, the temperature is set to (T + 273) by adding 273 to the temperature of Celsius (° C.) in order to use the Kelvin temperature (absolute temperature) as the denominator. Two straight lines can be drawn from the test results of 4 conditions. These straight lines are parallel. If they are not parallel, acceleration is not performed with the same activation energy E and the same acceleration β, so the test conditions of temperature and humidity are changed. The activation energy E is obtained by multiplying the slope of this straight line by the Boltzmann constant.

  Similarly, FIG. 8 plots these times in a graph of “1 / humidity” and time. In this case as well, the temperature can be drawn on two straight lines. These straight lines are parallel. If they are not parallel, acceleration is not performed with the same activation energy E and the same acceleration β, so the test conditions of temperature and humidity are changed. The slope of this straight line represents the humidity acceleration β.

From the equation (1), when the time for _R1 is L _R1 and the constant in _R1 is A _R1 , L _R1 = A _R1 · EXP (E / k (T + 273))) · EXP (β / RH). From this equation, it is expressed as Equation 5.

  In addition, when the resistance value is R2, it is expressed by Equation 6.

  Further, when the resistance value is Rn, it is expressed by the following equation (7).

The test conditions of temperature / humidity and t ₁₁ , t ₁₂ , t ₂₁ , t ₂₂ until R 1 satisfy the equation (5) (L = _{R 1} = t ₁₁ when T = T 1 and RH = φ 1 are substituted, and T = Substituting T1, RH = φ2 results in L _R1 = t ₁₂ , substituting T = T2, RH = φ1, results in L _R1 = t ₂₁ , and substituting T = T2, RH = φ2 results in L _R1 = t _22. Therefore, if ((E / k (T + 273)) + (β / RH)) is taken on the horizontal axis and the logarithmic time axis is taken on the vertical axis, t ₁₁ , t ₁₂ , t ₂₁ , t ₂₂ and the test conditions The points obtained by plotting the numerical values obtained by substituting the temperature / humidity into ((E / k (T + 273)) + (β / RH)) are straight lines. These are plotted in the graph of ((E / k (T + 273)) + (β / RH)) and time in FIG. 9, and a straight line can be drawn.

Here, how to obtain the time with respect to the temperature and humidity used for estimation of the accidental wear reliability will be described. The temperature Tx (° C.) and the humidity φx (% RH) are calculated by ((E / k (T + 273)) + (β / RH)) as the point (Tx, φx) in FIG. A line parallel to the time axis is drawn from that point, a line perpendicular to the time axis is drawn from the intersection i1 with the straight line, and the intersection with the time axis is Lx. It can be seen that the time to reach R1 is Lx when used at a temperature Tx (° C.) and humidity φx (% RH).
Similarly, the temperature Ty (° C.) and the humidity φy (% RH) are calculated by ((E / k (T + 273)) + (β / RH)), and the point (Ty, φy) in FIG. 9 is obtained. A line is drawn parallel to the time axis from that point, a line is drawn perpendicularly to the time axis from the intersection point i2 with the straight line, and if the intersection point with the time axis is Ly, temperature Ty (° C.) and humidity φy (% RH) It can be seen that the time to reach R1 is Ly in the use of.
That is, the temperature and humidity used for the estimation regarding the accidental wear reliability are (Tx, φx) or (Ty, φy), and the corresponding time is known.

How this concept is applied will now be described.
The installation environment conditions are as follows.
Installation environment condition 1: Immediately take measures to lower temperature and humidity.
Installation environment condition 2: Temperature / humidity conditions are severe, so lower the temperature / humidity.
Installation environment condition 3: Temperature / humidity conditions are within the assumed operating range.

  When the temperature and humidity of the installation environment conditions 1 to 3 are calculated by ((E / k (T + 273)) + (β / RH)) as the points in FIG. 10, each installation condition is obtained as shown in FIG. The time for R1 corresponding to 1 to 3 is obtained. The summary is shown in Table 1.

  As with R1, R2 ... Rn is also determined. The result is shown in FIG. Table 2 shows the time corresponding to each environmental installation condition for each R as determined in FIG.

As Table 2, the installation environment condition 1 R1 t _{R1_1} a time corresponding to a time corresponding to R2 t _{R2_1,} t _{Rn_1} a time corresponding to Rn, a time corresponding to R1 of the installation environment condition 2 t _The time corresponding to _{R1_2} and R2 is t _{R2_2} , the time corresponding to Rn is t _{Rn_2} , the time corresponding to R1 in the installation environment condition 3 is t _{R1_3} , the time corresponding to R2 is t _{R2_3} , and the time corresponding to Rn is t and _{Rn_3, R1~Rn,} and installation environment condition 1 corresponds to R1~Rn t _{R1_1} ~t _{Rn_1,} and corresponds to the installation environment condition 2 R1~Rn t _{R1_2} ~t _{Rn_2,} and the installation environment condition 3 R1 Save to the reference time storage unit as the data value for t _{R1_3} ~t _{Rn_3} corresponding to ～Rn.

As for the correspondence between installation environment conditions and time, data as shown in Table 2 may be stored in the reference time storage unit, or the temperature / humidity, activation energy E, acceleration β, and Boltzmann constant of each installation environment condition. The data of A _R1 to A _Rn of k and Formulas 5 to 7 may be stored in the reference time storage unit and calculated from Formulas 5 to 7.

  When the numerical control device is installed and operated, the resistance value of the conductive film is measured, and the measured resistance value and the corresponding time are stored in the measured value storage unit. It is assumed that the resistance value measured at the time of manufacturing the numerical control device and the time at the time of measurement are already stored as necessary. For example, it may be necessary when the device is used after correcting the time from the manufacture to the start of use, such as when the storage state is unknown since the device is manufactured until the start of use by the user. After that, for example, the resistance value of the conductive film is checked every day or every week. The time corresponding to the measurement value may be any of the time at that time (measurement time), the elapsed time from the start of use, or the elapsed time from the previous measurement.

  Table 3 is a table for explaining an example in which the resistance measurement values and the corresponding measurement time and elapsed time are stored in the measurement value storage unit.

R _{m — 0 in} Table 3 is a measured value of the resistance of the conductive film in the initial _stage of operation. For example, Y ₀ : M ₀ : D ₀ : h ₀ (Y = year, M = month, D = day, h = time) indicating year, month, day, and time is stored as the time corresponding to the measurement value. And Therefore, the time corresponding to the measurement value in this case is the measurement time. R _{m_R1} is a resistance value when it is determined that R1 has been reached. If the time at that time is Y _R1 : M _R1 : D _R1 : h _R1 , the elapsed time t _{m_R1} is Y _R1 : M _R1 : D _R1 : It is assumed that a value obtained by subtracting Y ₀ : M ₀ : D ₀ : h ₀ from h _R1 is stored in the measurement value storage unit as the elapsed time. If the time is stored, the elapsed time can be obtained by calculation, but it is assumed that the elapsed time is also stored for easy explanation.

Similarly, when it is determined that R2 has been reached, it continues from the time when it has been determined that R3 has been reached. In general, it is assumed that the product value is reached before the resistance value stored in the measurement value storage unit reaches Rn stored in the reference time storage unit.
In the example, the data when R1 or R2 is reached is stored, but the resistance value measured for each other measurement and the corresponding measurement time and elapsed time may be stored individually. In Tables 3 and 4, data for each measurement is not stored. In addition, it is arbitrary whether to memorize all or to memorize.

  Table 4 is a table for explaining an example of data in which the elapsed time is stored in the measurement value storage unit.

R _{m — 0 in} Table 4 is a measured value of the resistance of the conductive film in the initial _stage of operation, and is the same as R _{m — 0 in} Table 3, but the time is, for example, a timer start time. Accordingly, 0 is entered in the elapsed time column corresponding to t _{m — 0} in Table 4. _{Rm_R1 in} Table 4 is a resistance value when it is determined that R1 is reached, and is the same as _{Rm_R1} in Table 3, but the corresponding time is _{tm_R1} from the timer start. Therefore, in this case, t _{m_R1} is the elapsed time. The same applies hereinafter. In the following description, Table 3 is used.

Next, measurement of the resistance value of the conductive film will be described.
The resistance value measurement / comparison (determination) / memory / alarm output circuit 50 is configured, for example, as a resistance value / comparison (determination) / memory / alarm output unit in FIG. Rx is a known resistance. The conductive film Rp is a resistance of the conductive film whose resistance value increases with elapsed time corresponding to temperature and humidity. Reference numeral 51 is a resistance value measuring unit, 52 is an OP amplifier, 53 is an A / D converter, 54 is a comparison (determination) unit, 55 is a storage unit, and 56 is an alarm output unit. When the resistance Rx and the conductive film Rp are connected as in the resistance value measurement / comparison (determination) / memory / alarm output unit of FIG. 13 and the voltage at the connection point between Rx and Rp is Vx, the resistance value of the conductive film Rp is , Which is obtained by the equation (8). In Equation 8, the resistance value of the conductive film Rp is simply expressed as Rp. Specifically, the comparison (determination) unit 54 is a processor (CPU) that performs a comparison (determination) process. The storage unit 55 is a memory, and is, for example, a flash ROM (flash ROM), a power-backed RAM, an EEPROM, or the like.

  The connection point between the resistor Rx and the conductive film Rp is connected to + (plus) of the OP amplifier 52, and-(minus) of the OP amplifier 52 is connected to the output of the OP amplifier. This is a so-called voltage follower connection. Since the output of the OP amplifier 52 outputs Vx, it is connected to the input of the A / D converter 53, and the A / D converter 53 converts the analog value Vx into a digital value. The digital value of the A / D converter 53 is input to the comparison (determination) unit 54. Since the comparison (determination) unit 54 knows the value of Vx as a digital value, the resistance value of the conductive film Rp is obtained using Equation (8).

At the beginning of operation, the measured Rp resistance value (for example, R _{m — 0} ) and the time (for example, Y ₀ : M ₀ : D ₀ : h ₀ ) are measured value storage units corresponding to Table 3 (predetermined values in the storage unit 55). Storage area). Thereafter, the measured resistance value of Rp is compared with the data of R1 stored in the reference time storage unit (predetermined storage area of the storage unit 55). When R1 is eventually reached (R1 ± y% (y is an arbitrary value) Number)), or when R1 is exceeded, the R1 resistance value (the resistance value when Rp becomes R1 is _{Rm_R1} ) is stored in the measurement value storage unit corresponding to Table 3 ( For example, Y _R1 : M _R1 : D _R1 : h _R1 is stored), and Y _R1 : M _R1 : D _R1 : h _R1 -Y ₀ : M ₀ : D ₀ : h ₀ is calculated and the elapsed time t _{m_R1} is calculated. Remember.

Compared with t _{M_R1} measured value storage, t _{R1_1} reference value o'clock R1 stored in the storage unit installation environment condition 1, the installation environment condition 2 t _{R1_2,} as follows t _{R1_3} installation environment condition 3 As a result of comparison, the operation of the described example is performed.

t _{m_R1} <t _{R1_1}
Then, the comparison (determination) unit 54 determines that there is an abnormality, and performs the following operation as an example. The comparison (determination) unit 54 outputs an alarm output to the alarm output unit 56 that the temperature / humidity is very high, and immediately gives a warning to lower the temperature / humidity. If the indicator of the alarm output unit 56 is used as it is, a failure will occur soon, so that the temperature / humidity is immediately displayed on the screen, the stack light and warning light are lit red, and the buzzer emits an emergency sound. Notify the workers, etc. to respond urgently by issuing

t _{R1_1} ≦ t _{m_R1} ≦ t _{R1_2}
In, t _{M_R1} is determined comparison (determination) unit 54 if closer to t _{R1_1} than t _{R1_2} abnormal, a warning considerable _t m_R1.
If t _{m_R1} is close to t _{R1_2} , the comparison (determination) unit 54 determines that the temperature / humidity is high, outputs an alarm that the temperature / humidity is high, and warns the temperature to be lowered because the temperature / humidity is high. The alarm output unit 56 has a high temperature / humidity display so that the temperature / humidity is lowered, the stack light and warning light are lit in orange, and the buzzer emits a somewhat urgent sound. In the future, it will be reported to the workers etc. that it will be a problem if it continues to be used as it is. The resistance value of t _{M_R1} is better to change the manner of warning by whether around the t _{R1_1} and t _{R1_2} throat.

t _{R1_2} ≦ t _{m_R1} <t _{R1_3}
2, the comparison (determination) unit 54 determines that the temperature / humidity is high, or determines that the temperature / humidity is slightly high, _{depending on} where t _{m_R1 is} between t _{R1_2} and t _{R1_3} . The comparison by the judgment (determination) unit 54 the above t _{M_R1} considerable alarm output when close to t _{R1_2,} or a warning, that the temperature and humidity is slightly higher than normal and alarm output warning (alarm output unit The 56 display shows that the temperature and humidity are slightly high, the stack light and warning light turn on yellow, and the buzzer emits a non-emergency sound. To the workers, etc.) or to keep it internally without warning.
t _{R1_3} ≦ t _{m_R1}
Then, the comparison (determination) unit 54 determines that there is no problem.
Similarly, when R2 is reached, time t _{m_R2} until R2 is used, and t _{R2_1} , t _{R2_2} , t _{R2_3} are compared in the same manner (the same processing as R1 described above is performed).
The same applies hereinafter.

  Although the elapsed time is used in the above description, it is needless to say that the difference between the measurement times may be stored by storing only the measurement time without storing the elapsed time in advance.

In addition, the above is a comparison of time and analogy of the installed environment. As shown in FIG. 12, from _{Tm_Rx} (x is 1 to n) of the measurement storage unit ((E / k (T + 273)) + The value of (β / RH) may be obtained and compared with the value of ((E / k (T + 273)) + (β / RH)) in the installation conditions 1 to 3.

  In addition, when the resistance value measured at the time of manufacture is memorize | stored in the measured value memory | storage part, the resistance value measured at the time of an operation start can be compared, and the preservation | save state before a use start can be known. It can be used as information at the time of maintenance, or an alarm can be output depending on the degree of increase in resistance value.

  In the above description, the elapsed time until reaching a certain resistance value is used. Here, a case where the installed environmental condition is judged from the increment of time and the increment of resistance value will be described. A description will be given assuming that data is already stored in the measurement value storage unit of Table 3. Assuming that the measured resistance value of the conductive film Rp is R1, R2, R3,..., The time increment and the resistance value increment can be expressed by Equation (9).

  This is calculated in the resistance value measurement unit / calculation and comparison (determination) unit / storage / alarm output circuit 60 and comparison (determination) unit 64 of FIG. A calculation unit that calculates Equation 9 is referred to as a “measurement ratio calculation unit”.

  For example, from Table 2, in the installation environment condition 1, the increase in time and the increase in resistance value of the installation environment conditions 1 to 3 stored in the reference time storage unit are several tens of equations.

  In installation environment condition 2, Formula 11 is used.

  In the installation environment condition 3, Equation 12 is used.

  The value of increment of time / increment of resistance value is obtained by Equations 10-12. It is assumed that the values of R1, R2, R3, R4,... Are already stored in the reference value storage unit (a predetermined storage area of the storage unit 65). The resistance value measurement / calculation and comparison (determination) / storage / alarm output circuit 60 calculation / comparison (determination) unit 64 shown in FIG. 14 is used as the calculation and comparison (determination) unit. The calculation of Expressions 10 to 12 is referred to as “reference ratio calculation unit”. Specifically, the calculation and comparison (determination) unit 64 is a processor (CPU) that performs calculation and comparison (determination) processing. The storage unit 65 is a memory, and is, for example, a flash ROM (flash ROM), a power-backed-up RAM, an EEPROM, or the like.

  When the resistance value of the conductive film Rp is measured and the resistance value becomes Rj (j ≧ 1), the “measurement ratio” of the time increment / resistance increment is obtained from the equation (9). The actual installation environment condition is judged by comparing with the “reference ratio” of the installation environment conditions 1 to 3 obtained from the equation 12, and compared with the “reference ratio” of the corresponding installation environment examinations 1 to 3 Judge the conditions and output an alarm according to the corresponding installation environment conditions.

  In the above, the installation environment conditions are divided into three, but it is needless to say that more detailed alarms and cautions can be given if divided into many installation environment conditions. Moreover, it is good also as one instead of two or more.

  Regarding the data in the measured value storage unit (memory 65), for example, the environmental conditions (temperature / humidity) that are used when the measured value storage unit data is read via a telephone line or the Internet every time a failure occurs or at regular intervals. Because it is possible to know the product, it is possible to review the product and improvement, installation environment conditions.

By providing the conductive film 5 used in the embodiment of the present invention on the locker 70 as shown in FIG. 15, it is possible to detect the temperature and humidity around the locker, and to cope with accidental failure or wear failure of the touch panel or the like. Can do. Also, as shown in FIG. 16, by providing the plate 72 in the rocker 70, it is possible to deal with accidental or wear failure of the unit 74 or parts in the rocker. Alternatively, as shown in FIG. 17, by providing on the printed board 76 on which the components are mounted, it is possible to cope with an accidental failure or a wear failure with respect to the components on the printed board 76 or the unit 74.
Further, the present invention is not limited to application to a numerical control device that controls a machine tool, and can be applied to various electronic devices.

4 Insulating base material having water vapor permeability 5 Conductive film 6 Electrode 7 Insulating base material not having water vapor permeability

9 Wiring pattern

50 Resistance value measurement / comparison (judgment) / memory / alarm output circuit 51 Resistance value measurement unit 52 OP amplifier 53 A / D converter 54 Comparison (judgment) unit 55 Memory 56 Alarm output unit

60 Resistance value measurement / calculation and comparison (judgment) / memory / alarm output circuit 61 Resistance value measurement unit 62 OP amplifier 63 A / D converter 64 Calculation and comparison (judgment) unit 65 Memory 66 Alarm output unit

70 lockers 72 boards 74 units 76 printed boards

Rx resistance Rp conductive film F (t) cumulative percentage RH humidity T temperature

Claims (6)

An installation environment determination apparatus that is provided in an electronic device and determines an installation environment of the electronic device, and a conductive film provided on a circuit in the electronic device,
A measurement unit for measuring the resistance value of the conductive film at predetermined time intervals or at predetermined timing;
A measured value storage unit for storing the resistance value measured by the measurement unit in association with the elapsed time from the start of use or the elapsed time from the manufacture;
A reference time storage unit that stores the relationship between the resistance value of the conductive film at the reference temperature and humidity and the elapsed time used as the reference time;
A comparison unit that compares the elapsed time when the measured resistance value becomes a predetermined resistance value and the elapsed time at the reference time;
As a result of the comparison by the comparison unit , if the use is continued at the temperature and humidity of the installation environment of the electronic device, it is shorter when it is determined that the number of years becomes shorter than the expected years until the wear failure period (life) of the electronic device. a comparison result output unit for outputting an alarm in response to the degree made, installation environment determination apparatus of an electronic device characterized by having a. An installation environment determination apparatus that is provided in an electronic device and determines an installation environment of the electronic device, and a conductive film provided on a circuit in the electronic device,
A measurement unit for measuring the resistance value of the conductive film at predetermined time intervals or at predetermined timing;
A measurement value storage unit for storing the resistance value measured by the measurement unit in association with the measurement time;
A reference time storage unit that stores the relationship between the resistance value of the conductive film at the reference temperature and humidity and the elapsed time used as the reference time;
A comparison unit that compares the elapsed time from the start of use calculated from the measurement time when the measured resistance value becomes a predetermined resistance value or the elapsed time from the manufacturing time and the elapsed time in the reference time;
As a result of the comparison by the comparison unit , if the use is continued at the temperature and humidity of the installation environment of the electronic device, it is shorter when it is determined that the number of years becomes shorter than the expected years until the wear failure period (life) of the electronic device. a comparison result output unit for outputting an alarm in response to the degree made, installation environment determination apparatus of an electronic device characterized by having a. An installation environment determination apparatus that is provided in an electronic device and determines an installation environment of the electronic device, and a conductive film provided on a circuit in the electronic device,
A measurement unit for measuring the resistance value of the conductive film at predetermined time intervals or at predetermined timing;
A measured value storage unit for storing the resistance value measured by the measurement unit in association with the elapsed time from the start of use or the elapsed time from the manufacture;
A reference time storage unit that stores the relationship between the resistance value of the conductive film at the reference temperature and humidity and the elapsed time used as the reference time;
A measurement ratio calculation unit that calculates a measurement ratio between an increase in elapsed time and an increase in resistance value from the resistance value stored in the measurement value storage unit and the elapsed time when the measured resistance value becomes a predetermined resistance value; ,
A reference ratio calculation unit that calculates a reference ratio between an increment of elapsed time calculated from the resistance value stored in the reference time storage unit and an elapsed time and an increment of resistance value;
A comparison unit for comparing the calculated measurement ratio with a reference ratio;
As a result of the comparison by the comparison unit , if the use is continued at the temperature and humidity of the installation environment of the electronic device, it is shorter when it is determined that the number of years becomes shorter than the expected years until the wear failure period (life) of the electronic device. a comparison result output unit for outputting an alarm in response to the degree made, installation environment determination apparatus of an electronic device characterized by having a. An installation environment determination apparatus that is provided in an electronic device and determines an installation environment of the electronic device, and a conductive film provided on a circuit in the electronic device,
A measurement unit for measuring the resistance value of the conductive film at predetermined time intervals or at predetermined timing;
A measurement value storage unit for storing the resistance value measured by the measurement unit in association with the measurement time;
A reference time storage unit that stores the relationship between the resistance value of the conductive film at the reference temperature and humidity and the elapsed time used as the reference time;
When the measured resistance value becomes a predetermined resistance value, a measurement ratio calculation unit that calculates a measurement ratio between an increase in elapsed time and an increase in resistance value from the resistance value and time stored in the measurement value storage unit;
A reference ratio calculation unit that calculates a reference ratio between an increment of elapsed time calculated from the resistance value stored in the reference time storage unit and an elapsed time and an increment of resistance value;
A comparison unit for comparing the calculated measurement ratio with a reference ratio;
As a result of the comparison by the comparison unit , if the use is continued at the temperature and humidity of the installation environment of the electronic device, it is shorter when it is determined that the number of years becomes shorter than the expected years until the wear failure period (life) of the electronic device. a comparison result output unit for outputting an alarm in response to the degree made, installation environment determination apparatus of an electronic device characterized by having a.   The comparison result output unit is configured such that an elapsed time when the predetermined resistance value is reached is shorter than the reference time, or a difference between the elapsed time when the predetermined resistance value is reached and the reference time is predetermined. The apparatus installation environment determination device according to claim 1, wherein an alarm is output when the range is within the range.   A plurality of the reference times are provided, and the comparison result output unit outputs an alarm or a message corresponding to the closest reference time among the plurality of reference times when the predetermined resistance value is reached. The electronic device installation environment determining apparatus according to any one of claims 1 to 4.

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