KR20180111569A - Deterioration diagnostic apparatus and method - Google Patents

Abstract

The present invention can more simply and quickly determine the abnormality of a hater. A control value determining unit (103) determines whether a control value is an off control value for turning off the heater (111) or an on control value for turning on the heater (111). A delay acquiring unit (105) acquires a measurement value which a current measuring unit (104) measures at a time point at which a delay time elapses from an on execution time point at which the control value determining unit (103) executes from an off control value determination state to an on control value determination state. A deterioration determining unit (106) determines that the heater (111) of an operating unit (112) is deteriorated if the measurement value acquired at the elapsed time point in the delay acquiring unit (105) exceeds an allowable range.

Description

TECHNICAL FIELD [0001] The present invention relates to a deterioration diagnostic apparatus,

The present invention relates to a deterioration diagnosis apparatus and method for diagnosing degradation of a heating apparatus having a heater.

In the industrial process, there are many processes for heating the material. In such a heating process, an electric heater (heater) is generally used. Further, in the operation control of the electric heater, a temperature controller is used. The temperature controller uses a temperature sensor such as a thermocouple or a temperature-measuring resistor to measure the temperature of the object to be treated (object to be monitored) heated by the heater. The measured temperature is displayed numerically on the temperature controller.

Further, in the temperature controller, the control output (MV value) is obtained according to the detected temperature (PV value) and the set temperature (SP value). The obtained control output is outputted to a heater operation device by a power regulator or the like. In the heater controller, the driving current of 100 V from the commercial power source is controlled in accordance with the control output to be output to the heater. The temperature of the object to be treated is controlled by heating the heater thus controlled. The temperature controller includes an abnormality detecting function to detect abnormality of the object to be monitored and abnormality of the temperature sensor and to output the detected abnormality as event information to generate an alarm ). For example, an alarm is displayed with an indicator for numerically displaying the temperature.

Further, in the temperature controller, an abnormality of the heater itself such as breakage of the heater is detected (see Patent Documents 1 and 2). For example, the current / voltage applied to the heater is measured to obtain the effective value power, the resistance value is obtained from the relationship between the current and the voltage, and the deterioration of the heater is determined from the difference between the obtained resistance value and the variation degree Patent Document 1). Further, heater deterioration is judged by using data obtained by tabulating actual measurement points of the control output and the current value (see Patent Document 2).

Patent Document 1: Japanese Patent No. 2683851 Patent Document 2: Japanese Patent No. 3988942

However, in the above-described technique, it is first necessary to measure the current flowing through the heater and the voltage applied to the heater. Further, in the above-described technique, calculation of a parameter for abnormality diagnosis such as resistance value is complicated. Further, in the above-described technique, there is a problem that it takes time to measure the elapsed time or the like in order to investigate the time change of the resistance value. Thus, in the above-described technique, complicated calculation and measurement were required until the above-mentioned judgment was made.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and it is an object of the present invention to make it easier to more quickly determine the abnormality of a heater.

The deterioration diagnosis method according to the present invention determines the upper permissible value and the lower permissible value with respect to the current value supplied to the heater in accordance with the control value given to the heating apparatus at the normal time of the heater constituting the heating apparatus to be subjected to deterioration diagnosis, A first step of setting a permissible range for judging a deterioration of the apparatus; a second step of measuring the time from when the heater is changed from the off state to the on state at the normal time until the current value supplied to the heater reaches the permissible range, A third step of determining whether the control value is an off control value for turning off the heater or an on control value for turning on the heater in the third step; At the time point when the delay time has elapsed from the transition point from the state of being judged as the OFF control value to the state of being judged as the ON control value, A fourth step of obtaining a measured value by measuring a supplied current and a fifth step of determining that the heating device has deteriorated if the measured value obtained at the elapsed time point exceeds the permissible range in the fourth step .

In the deterioration diagnosis method, in the fourth step, the current supplied to the heater from the on-transition point to the elapsed time point is measured to acquire the measured value. In the fifth step, the time when the measured value exceeds the allowable range is set When the determination time is exceeded, it may be determined that the heating device has deteriorated.

A sixth step of measuring a current supplied to the heater in a state where the control value is determined to be an OFF control value in the third step and obtaining a measured value; And a seventh step of judging that an abnormality has occurred in the heater when the abnormality determination time other than the vicinity of 0 is continued.

The deterioration diagnosis apparatus according to the present invention is characterized in that the deterioration diagnosis apparatus further comprises an upper limit permissible value and a lower permissible limit value set with respect to a current value supplied to the heater in accordance with a control value given to the heating apparatus when the heater constituting the heating apparatus, And a control unit for controlling the heater unit so that the current value supplied to the heater after changing the heater from the off state to the on state at the normal time becomes the allowable range A control value judging unit configured to judge whether the control value is an off control value for turning the heater off or an on control value for turning on the heater, A current measuring unit configured to measure a current supplied to the heater; and a current measuring unit configured to measure a current supplied to the heater, A delay acquisition section for acquiring a measured value measured by the current measuring section at a time point at which a delay time elapses from a transition point from the on transition time determined to be the ON control value; And if it exceeds the range, it is determined that the heating apparatus has deteriorated.

In the deterioration diagnosis apparatus, the delay acquisition section is configured to acquire a measurement value measured by the current measurement section from the on transition point to the elapsed time point, and the deterioration determination section determines that the measured value acquired by the delay acquisition section exceeds the allowable range , And when it is determined that the set time has passed, it is determined that the heating apparatus has deteriorated.

A stop-state acquisition unit that measures a current supplied to the heater in a state where the control value is determined to be an off-control value by the control value determination unit and acquires a measured value; The abnormality determination section may determine that an abnormality has occurred in the heater when the abnormality determining section determines that the abnormality determining section determines that the abnormality has occurred.

As described above, according to the present invention, it is possible to obtain an excellent effect that the abnormality of the heater can be judged more easily and more quickly.

1 is a configuration diagram showing the configuration of a degradation diagnosis apparatus 100 according to Embodiment 1 of the present invention.
2 is a flowchart for explaining a deterioration diagnosis method in Embodiment 1 of the present invention.
3 is a configuration diagram showing the configuration of the degradation diagnosis apparatus 100 according to the second embodiment of the present invention.
4 is a flowchart for explaining the degradation diagnostic method in the second embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[Embodiment 1]

First, Embodiment 1 of the present invention will be described with reference to Fig. 1 is a configuration diagram showing the configuration of a degradation diagnosis apparatus 100 according to Embodiment 1 of the present invention. The deterioration diagnosis apparatus 100 includes a reference storage unit (first storage unit) 101, a delay time storage unit (second storage unit) 102, a control value determination unit 103, a current measurement unit 104, A delay acquisition section 105, a deterioration judgment section 106, and a display section 107. [ The deterioration diagnosis apparatus 100 diagnoses the deterioration of the heating apparatus including the heater 111 and the operating section 112. [

The reference storage unit 101 stores an allowable range (normal range) for the deterioration diagnosis of the heater 111 and the operation unit 112. [ The permissible range is set from the upper permissible value and the lower permissible value of the current value supplied to the heater 111 in accordance with the control value given to the operating section 112 (heating device) at the normal time. The permissible range is used for determining the deterioration of the heater 111 and the operating portion 112 (heating device).

For example, a reference line is created by using heater characteristics showing the relationship between the continuously changing control value given to the heater 111 and the change of the current in the heater 111 at the normal time corresponding to the control value. The heater characteristic itself may be used as a reference line. The heater characteristic may be approximated to the line and used as the reference line. The reference line may also be created by discretionally varying the control value and the discrete approximate current value corresponding to the discrete changing current value in the heater 111 at the normal time corresponding to the control value.

The permissible range may be set from the upper permissible value and the lower permissible value of the current value for the control value at this reference line. A range between the upper permissible value line corresponding to the upper permissible value of the current value with respect to the control value at the reference line and the lower permissible value line corresponding to the lower permissible value of the current value with respect to the control value at the reference line, 112) is regarded as normal.

The delay time storage unit 102 measures the time until the current value supplied to the heater 111 after changing the control from the OFF state to the ON state of the heater 111 at the normal time is within the allowable range Remember the delay time. The above time may be measured in advance.

The control value determining section 103 determines whether the control value is an off control value for turning the heater 111 off or an on control value for turning the heater 111 on. Each control value is output from the control unit 113. [ Each control value is calculated by the control unit 113 from the measurement value measured by the temperature measurement unit 114 and the set value that has been set, and is output to the operation unit 112.

The controller 113 is, for example, a temperature controller. The operation unit 112 is constituted by, for example, a well-known power regulator. The control unit 113 outputs an OFF control value or an ON control value by well-known ON / OFF control. Also, the control unit 113 changes not the fixed cycle but the output time of the ON control value and the output time of the OFF control value in accordance with the deviation between the temperature measurement value and the temperature setting value, and outputs the output. By performing such control, more stable temperature control can be performed.

Upon receiving the ON control value, the operating section 112 supplies a driving current of 100 V obtained from a commercial power source to the heater 111 to turn the heater 111 ON. On the other hand, when receiving the OFF control value, the operating section 112 stops supplying the driving current to the heater 111 and turns the heater 111 off. The control value acquisition unit 103 is a functional unit for acquiring an off control value or an on control value output from the control unit 113 (see Patent Document 1).

The current measuring unit 104 measures a current supplied to the heater 111. [ For example, the current measuring unit 104 acquires an effective current value as a measured value. The current measuring unit 104 is constituted by, for example, a well-known current transformer. In Embodiment 1, the current measuring unit 104 is used for alarm output in the control unit 113 which is a temperature control system. In this case, the current measuring unit 104 detects the driving current value to the heater 111 and outputs it to the control unit 113. The control unit 113 compares the detected alarm level with the preset alarm level, When the alarm level is exceeded, an alarm signal indicating abnormality of the heating temperature is outputted. The measured value may be an average current value.

The delay acquiring section 105 acquires the delay value from the time point when the control value determining section 103 has transitioned from the state in which the control value is determined to be the OFF control value to the state in which it is determined that the control value is in the ON control value, The measurement value measured by the current measuring unit 104 is acquired.

The deterioration determining section 106 determines that the heater 111 or the operating section 112 (heating device) has deteriorated when the measured value acquired at the elapsed time point in the delay acquiring section 105 exceeds the permissible range. For example, when the measured value acquired by the delay acquisition section 105 is smaller than the lower permissible value constituting the permissible range or higher than the upper permissible value, the deterioration judging section 106 judges that the heater 111 or the operation section 112 ).

The delay acquisition unit 105 may be configured to continuously acquire the measured values measured by the current measurement unit 104 from the on transition time point to the elapsed time point. In addition, when the sum of the times at which the measured value acquired by the delay acquisition section 105 exceeds the allowable range exceeds the set determination time, the deterioration determining section 106 determines that the heater 111 ) Or the operating section 112 has deteriorated.

For example, when the on-control and the off-control are switched at short intervals, measurement may not be possible even if the measured value exceeds the allowable range. Also, even if the measurement is made, determination can not be made if the measured value between the delay times is not used for determination, and the ON / OFF is switched before the delay time elapses. In this case, as described above, the measurement values are successively acquired, and when the sum of the time that has become the abnormal value exceeds the determination time, the deterioration may be determined.

According to the determination of the deterioration described above, it is possible not only to deteriorate the heater 111, but also to determine deterioration or failure in the operating section 112. [ The current supplied to the heater 111 may become abnormal even by the unstable operation of the operating unit 112 even when the heater 111 is not abnormal.

It should be noted that the tolerance range and the control point obtained by the control value acquisition section 103 and the measurement point in accordance with the measurement value acquired by the current measurement section 104 are set on the coordinates of the two- The arranged graph is displayed on the display unit 107. The above-described reference line may be displayed on the display unit 107 together with the allowable range.

The degradation diagnosis apparatus 100 is a computer apparatus having a CPU (Central Processing Unit), a main storage unit, an external storage unit, and a network connection unit. In the deterioration diagnosis apparatus 100 as a computer device, the above-described functions are realized by the CPU being operated by a program developed in the main memory device. In addition, each function may be distributed to a plurality of computer devices.

Next, an operation example (deterioration diagnosis method) of the deterioration diagnosis apparatus 100 according to the first embodiment of the present invention will be described with reference to the flowchart of FIG.

First, in step S201, an allowable range for determining the deterioration of the heater 111 to be subjected to deterioration diagnosis is set and stored in the reference storage unit 101 (first step). The permissible range is set by setting the upper permissible value and the lower permissible value with respect to the current value supplied to the heater 111 according to the control value for the operating portion 112 at the normal time.

Next, in step S202, a delay time is set and stored in the delay time storage unit 102 (second step). The time from when the heater 111 is changed from the OFF state to the ON state and when the current value supplied to the heater 111 falls within the allowable range is measured to be the delay time.

Next, in step S203, the deterioration determining section 106 determines the start of the determination. For example, determination is made by accepting input of an instruction to make a determination. Further, for example, the determination cycle time may be set, and the determination may be started upon the passage of the determination cycle time.

(Step S203: yes), the control value judging section 103 judges the control value from the control section 113 in step S204 (third step). The control value determining section 103 determines whether the control value is an off control value for turning the heater 111 off or an on control value for turning the heater 111 on.

Next, in step S205, it is determined whether or not the delay acquiring section 105 transitions from a state in which the off control value is acquired to a state in which the on control value is acquired. (Step S205: yes), in step S206, the delay acquiring section 105 acquires the control value from the state in which the current control section 104 acquires the control value And starts acquiring the measured value. Next, in step S207, the delay acquisition section 105 determines the elapse of the delay time stored in the delay time storage section 102. [ If it is determined that the delay time has elapsed (yes in step S207), the delay acquisition unit 105 ends the acquisition of the measured value and proceeds to step S208 (fourth step).

Next, in step S208, the deterioration judging unit 106 judges whether or not the measured value acquired by the delay acquiring unit 105 exceeds the allowable range at the time when it is judged that the delay time has elapsed. When the measured value exceeds the permissible range, the deterioration judging unit 106 judges that the heater 111 has deteriorated (fifth step). The deterioration determining section 106 determines whether or not the time when the measured value acquired by the delay acquiring section 105 from the on transition point to the elapsed time exceeds the allowable range exceeds the set determination time, It may be determined that the substrate 111 has deteriorated.

Next, when it is judged that the heater 111 has deteriorated (YES in step S208), the deterioration judging unit 106 notifies this state in step S209. For example, by displaying an alarm on the display unit 107, the user is notified of the deterioration judgment of the heater 111.

As described above, in Embodiment 1, deterioration is judged by exceeding the permissible range of the current value (measured value) measured in the actual use state. Therefore, according to the first embodiment, it is not necessary to calculate the parameters for determination, and it is not necessary to measure the time variation of the current value or the like. As a result, according to the first embodiment, it is possible to more easily determine the abnormality of the heater more quickly.

[Embodiment 2]

Next, a second embodiment of the present invention will be described with reference to Fig. 3 is a block diagram showing the configuration of the degradation diagnosis apparatus 100a according to the second embodiment of the present invention. The deterioration diagnosis apparatus 100a includes a reference storage unit (first storage unit) 101, a delay time storage unit (second storage unit) 102, a control value determination unit 103, a current measurement unit 104, A delay acquisition section 105, a deterioration judgment section 106, and a display section 107. [ These configurations are the same as those of the first embodiment described above. The deterioration diagnosis apparatus 100a according to the second embodiment includes a stopping acquisition unit 108 and an abnormality determination unit 109. [ The deterioration diagnosis apparatus 100a according to the second embodiment also makes the above determination in addition to the deterioration diagnosis of the heating apparatus including the heater 111 and the operation unit 112. [

The stop-state acquisition unit 108 acquires the measurement value measured by the current measurement unit 104 while the control value determination unit 103 determines that the control value is an OFF control value. The abnormality judging section 109 judges that an abnormality has occurred in the heater 111 when the state in which the measured value acquired by the acquisition section 108 at the time of stopping is other than 0 is continued for the set abnormality determination time.

The degradation diagnosis apparatus 100a is a computer apparatus having a CPU (Central Processing Unit), a main storage device, an external storage device, and a network connection device. In the deterioration diagnosis apparatus 100a as a computer device, the above-described functions are realized by the CPU being operated by a program developed in the main memory device. In addition, each function may be distributed to a plurality of computer devices.

Next, an operation example (deterioration diagnosis method) of the deterioration diagnosis apparatus 100a according to the second embodiment of the present invention will be described with reference to the flowchart of FIG.

First, in step S401, an allowable range for determining the deterioration of the heater 111 to be subjected to deterioration diagnosis is set and stored in the reference storage unit 101 (first step). The permissible range is set from the upper permissible value and the lower permissible value of the current value supplied to the heater 111 in accordance with the control value for the operating section 112 at the normal time.

Next, in step S402, the delay time is set and stored in the delay time storage unit 102 (second step). The time from when the heater 111 is changed from the OFF state to the ON state and when the current value supplied to the heater 111 falls within the allowable range is measured to be the delay time.

Next, in step S403, the deterioration determining section 106 determines the start of the determination. For example, determination is made by accepting input of an instruction to make a determination. Further, for example, the determination cycle time may be set, and the determination may be started upon the passage of the determination cycle time.

(Step S403: yes), in step S404, the control value determining section 103 determines the control value from the control section 113 (the third step). The control value determining section 103 determines whether the control value is an off control value for turning the heater 111 off or an on control value for turning the heater 111 on.

Next, in step S405, it is determined whether or not the delay acquiring section 105 transitions from a state in which the off control value is acquired to a state in which the on control value is acquired. (Step S405: yes), in step S406, the delay acquisition unit 105 determines whether the current measurement unit 104 has measured the current value And starts acquiring the measured value. Next, in step S407, the delay acquisition section 105 determines the elapse of the delay time stored in the delay time storage section 102. [ If it is determined that the delay time has elapsed (yes in step S407), the delay acquisition unit 105 ends the acquisition of the measured value and proceeds to step S408 (fourth step).

Next, in step S408, the deterioration judging unit 106 judges whether or not the measured value acquired by the delay acquiring unit 105 exceeds the allowable range when it is determined that the delay time has elapsed. When the measured value exceeds the permissible range, the deterioration judging unit 106 judges that the heater 111 has deteriorated (fifth step). The deterioration determining section 106 determines whether or not the time when the measured value acquired by the delay acquiring section 105 from the on transition point to the elapsed time exceeds the allowable range exceeds the set determination time, It may be determined that the substrate 111 has deteriorated.

Next, when it is judged that the heater 111 has deteriorated (yes in step S408), the deterioration judging unit 106 notifies this state in step S409. For example, by displaying an alarm on the display unit 107, the user is notified of the deterioration judgment of the heater 111.

On the other hand, if the delay acquiring unit 105 continues to acquire the OFF control value in step S405 and does not acquire the ON control value (NO in step S405), then in step S410, 108 acquires the measurement value measured by the current measuring unit 104. [ Next, in step S411, the abnormality judging section 109 judges whether or not the measured value acquired by the stopping-time obtaining section 108 is other than around zero. If the measured value is 0 (NO in step S411), the process returns to step S404, and the control value determining section 103 continues to determine the control value from the control section 113. [

On the other hand, when the measured value acquired by the acquisition unit 108 at the time of stopping is other than 0 (yes in step S411), in step S412, the abnormality determination unit 109 determines the time at which the measurement value other than around 0 is acquired I'll go. Next, in step S403, the abnormality determination section 109 determines whether or not the added time exceeds the set abnormality determination time. If the added time does not exceed the abnormality determination time (NO in step S413), the process returns to step S404, and the control value determining section 103 continues the determination of the control value from the control section 113. [

On the other hand, when the deterioration judging unit 106 judges that the addition time has exceeded the abnormality judging time (yes in step S413), this state (abnormality) is notified in step S411. For example, by displaying an alarm on the display unit 107, the user is notified of the abnormality of the heater 111. [

As described above, according to the second embodiment, it is possible to more easily determine the abnormality of the heater more quickly, similarly to the first embodiment. According to the second embodiment, since the current value is measured in the OFF state, it is possible to determine an abnormality such as disconnection of the heater.

As described above, according to the present invention, the abnormality of the heater can be judged more easily and more quickly. According to the present invention, the above-described determination may use an instantaneous value of the heater current value to be obtained periodically, and it is not necessary to determine the tendency of temporal change for determination, and the determination can be performed quickly.

In addition, since the allowable range based on the baseline is used, the allowable range is a continuous determination criterion within a range that the control value can take. Therefore, unlike the case of table reference or the like, it is not necessary to perform interpolation at the time of judgment. Further, since the value of the current flowing through the heater can be measured, it is not necessary to measure the voltage, and the resistance value does not need to be calculated.

However, the determination may be made as follows. For example, it may be determined that an abnormality is detected only when a large abnormality occurs by widening the allowable range setting. Further, the setting of the allowable range (difference from the reference line) may be determined by dividing into a plurality of steps. For example, it is determined that there is a possibility of deterioration in the first stage. In the second step, it is judged that there is a possibility that deterioration has progressed. In the third stage, it is judged that deterioration is certain. This abnormality is judged to be a failure or disconnection.

In the case where the heater current measurement value is always around 0 for any control value, it may be determined that the heater is disconnected (or a failure of the power regulator or a complete failure of the apparatus related to other heating).

When the delay time is set in the determination, if the abnormality of the instantaneous value occurs continuously for a predetermined number of times or more, it may be determined that the deterioration is the first time to be sure. Or, if the measured value is close to 0, it may be determined that the wire is broken. Thus, accurate determination can be made even if the allowable range is narrowed. Further, it is possible to judge the progress of the above by the width deviating from the normal range.

In addition, the heater current value is measured and determined. However, the measured value may exceed the allowable range due to a decrease in the power supplied to the instrument or a coincidence of the power regulator (operation unit). Therefore, even if the heater is replaced with a regular product after it is determined that there is an abnormality, if the above determination is not resolved, it can be known that there is a problem in a region other than the heater. As described above, the present invention can be used as a so-called loop diagnosis.

Here, the reference line will be described in more detail. As the reference line, the heater characteristic may be approximated to the line. The baseline approximated to the line is composed of one or more line segments (linear expressions) on the coordinates of the two-dimensional plane having the control value and the measured value as axes. By setting the allowable range using the reference line approximating the line, it is possible to reduce the amount of data to be maintained as the allowable range. Since the reference line is composed of a combination of straight lines (linear equation), the permissible range is composed of a combination of straight lines (linear equation), and the data amount is very small.

For example, the heater characteristics of the heater at the normal time may be measured, and the reference line may be obtained by approximating the line from the measured heater characteristics. A predetermined number of set points (break points) may be provided on the curve of the obtained heater characteristics under predetermined conditions, and the set points may be connected by a straight line (line segment) to be a reference line. Further, at a predetermined number of measuring points, a current to a control value at a normal heater (heating apparatus) is measured to obtain a current value, a set point corresponding to a predetermined number of control values and a current value is set, The reference line may be set by connecting adjacent set points in a straight line.

Nine set points are set on the curve in the coordinates of the two-dimensional plane about the control value and the measured value. In addition, a set point is set at least for the minimum value of the control value and the maximum value of the control value, respectively. Then, two adjacent set points are connected to each other by a straight line to create a reference line. For example, nine reference points are connected in order to create a reference line. The reference line is composed of eight line segments.

The set point for creating the reference line may be set as follows. First, the set points are arranged corresponding to the minimum value and the maximum value of the control value in the curve representing the heater characteristic in the coordinates of the two-dimensional plane having the control value and the measured value as axes, and a first approximation line do. In addition, predetermined upper permissible value lines and lower permissible value lines are set for the first approximation line. The area sandwiched between the upper permissible value line and the lower permissible value line becomes the candidate of the permissible range.

The first approximation line is determined by the two set points as described above and the curve is set in the candidate of the allowable range while the candidate of the allowable range is set and the maximum deviation of the first approximate line and the curve is set in advance Which is smaller than the allowable deviation. If the curve falls within the allowable range and the maximum deviation is less than the allowable deviation, the first approximation line is taken as the reference line.

On the other hand, when an area in which the curve exceeds the allowable range occurs, the curve and the deviation become the maximum value in the negative direction of the measured value with respect to the first approximation line, and the curve and the deviation in the positive direction of the measured value Find the part that gives the maximum value.

Next, a new set point is added on the curve in the two obtained portions. Next, a new second approximation line connecting the four control points is set by adding. Further, a predetermined upper permissible value line and a lower permissible value line are set for a new second approximation line.

It is confirmed that a curve enters the allowable range according to the upper permissible value line and the lower permissible value line thus obtained and the maximum deviation of the second approximate line and the curve becomes smaller than the permissible deviation. For example, since the curve enters the allowable range at this stage and the maximum deviation of the second approximate line and the curve is smaller than the allowable deviation, the second approximate line is set as the reference line.

According to the above-described method for creating the reference line, the allowable range in which practical deterioration determination can be performed can be set without unnecessarily increasing the set point by properly setting the maximum deviation. Further, the approximate curve can be determined only by comparing with the maximum deviation from the allowable deviation, without making a comparison with the permissible range, according to the setting condition of the allowable deviation.

In addition, the reference line may be created as follows. First, a plurality of control values are set within a range of the minimum and maximum control values in a normal heater (heating apparatus), and a heater current value is measured at each set control value. For example, the control value is varied in the range of 0 to 100% to 10% width, and the heater current value is measured at each control value. Using the plurality of set points corresponding to the respective control values and the heater current values obtained as a result of this measurement, the line connecting the adjacent set points by a straight line is defined as a reference line approximating the line heater characteristics.

The present invention is not limited to the embodiments described above, and it is obvious that many modifications and combinations can be made by a person having ordinary skill in the art within the technical scope of the present invention.

101: reference storage unit (first storage unit) 102: delay time storage unit (second storage unit)
103: Control value judging unit 104: Current measuring unit
105: delay acquisition section 106: deterioration judgment section
107: Display portion 111: Heater
112: operating section 113:
114: Temperature measuring unit

Claims (6)

The upper limit permissible value and the lower permissible limit value are set with respect to the current value supplied to the heater in accordance with the control value given to the heating device at the normal time of the heater constituting the heating apparatus to be subjected to the deterioration diagnosis, A first step of setting a permissible range for the light-
A second step of measuring the time from when the heater is changed from the OFF state to the ON state and then the current value supplied to the heater falls within the allowable range,
A third step of determining whether the control value is an off control value for turning off the heater or an on control value for turning on the heater,
In the third step, the heater is supplied to the heater at a time point at which the delay time elapses from a transition point from a transition from a state in which the control value is determined to be the OFF control value to a state in which the control value is determined to be the ON control value A fourth step of measuring a current to acquire a measured value,
And a fifth step of determining that the heating device is deteriorated if the measured value acquired at the elapsed time point exceeds the allowable range in the fourth step. The method according to claim 1,
In the fourth step, the current supplied to the heater from the on-transition point to the elapsed time point is measured to obtain a measured value,
Wherein in the fifth step, when the time when the measured value exceeds the allowable range exceeds a set determination time, the deterioration diagnosis method determines that the heating apparatus has deteriorated. 3. The method according to claim 1 or 2,
A sixth step of measuring a current supplied to the heater in a state where the control value is determined to be the OFF control value in the third step and obtaining a measured value;
And a seventh step of determining that an abnormality has occurred in the heater when the abnormality determination time in which the measured value acquired in the sixth step is other than 0 is continued Lt; / RTI > The deterioration judgment of the heating device, which is set from the upper permissible value and the lower permissible value determined for the current value supplied to the heater in accordance with the control value given to the heating device at the normal time of the heater constituting the heating device to be subjected to deterioration diagnosis, A first storage unit for storing a permissible range for performing the above-
A second storage section for storing a delay time obtained by measuring a time until the current value supplied to the heater after changing the heater from the OFF state to the ON state at the normal time falls within the allowable range,
A control value determining unit configured to determine whether the control value is an off control value for turning the heater off or an on control value for turning the heater on;
A current measuring unit configured to measure a current supplied to the heater;
Control value judging section judges that the current value of the current control section has reached the predetermined value at the time point when the delay time elapses from the transition point from the transition point from the state in which the control value is determined as the OFF control value to the state in which it is judged as the ON control value, A delay acquiring unit for acquiring a measurement value that is being performed,
And a deterioration judging unit configured to judge that the heating device has deteriorated when the measured value acquired at the elapsed time exceeds the allowable range. 5. The method of claim 4,
Wherein the delay acquiring unit is configured to acquire a measured value measured by the current measuring unit from the on transition point to the elapsed time point,
Wherein the deterioration judging section is configured to judge that the heating device has deteriorated when the time at which the measured value acquired by the delay acquiring section exceeds the allowable range exceeds a set judgment time Device. The method according to claim 4 or 5,
A stop-time acquisition unit that measures a current supplied to the heater in a state in which the control value determination unit determines that the control value is the OFF control value, and acquires a measured value;
And an abnormality judging section for judging that an abnormality has occurred in the heater when the abnormality determination time in which the measured value acquired by the stopping-time acquiring section is other than 0 is set is continued.

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