JP2011199201A - Photocoupler device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photocoupler device accurately determining whether a photocoupler is in an output degraded state and elongating the service life of the photocoupler regardless of variations in quality or the like.SOLUTION: The device includes the first photocoupler P1 to be detected for degradation, a controller 1A controlling drive of the first photocoupler P1, an output detection circuit 3A generating and outputting a detection value which is a value corresponding to the potential of an output signal from the first photocoupler P1, and the second photo couplers P21, P22 transmitting the detection value output from the output detection circuit 3A to the controller 1A. The controller 1A is configured to perform a determining process of determining whether the first photocoupler P1 is in the output degraded state based on the detection value when the first photocoupler P1 is driven, and an adjusting process of increasing a drive power current of the first photocoupler P1 every time determination results in the output degraded state up to k times (k is a predetermined value of 2 or more).

Description

  The present invention relates to an apparatus using a photocoupler.

  Photocouplers are used as a means for transmitting signals between electrically insulated circuits. The deterioration of the photocoupler is caused by the deterioration of the LED, the deterioration of the internal insulating resin, or the like, and the current transfer ratio (CTR) is lowered. Conventionally, configurations for detecting deterioration of a photocoupler are disclosed in Patent Documents 1 and 2, for example.

  Patent Document 1 includes a comparator that compares the output voltage of the photocoupler with a preset threshold value, and whether or not the photocoupler has deteriorated based on the output signal of the comparator and the drive signal of the photocoupler. The structure which made it determine is disclosed.

  On the other hand, in Patent Document 2, the accumulated power-on time of the photocoupler is obtained, and when the accumulated power-on time exceeds a predetermined fixed time, it is determined that the aging deterioration has increased, and the light-emitting portion of the photocoupler is energized. A configuration is disclosed in which the current is increased to extend the service life of the photocoupler.

JP 2009-71928 A JP 2008-172513 A

  In the configuration of Patent Document 1, it is possible to detect the deterioration of the photocoupler, but the configuration for extending the service life of the photocoupler is not disclosed.

  Further, in the configuration of Patent Document 2, for example, the life of a photocoupler of the same product may be different due to quality variation or the like. In such a case, an increase in aging deterioration may be caused based on the accumulated power-on time. There is a problem that an accurate determination cannot be made even if it is determined.

  The present invention has been made to solve the above-described problems, and can accurately determine whether or not a photocoupler is in an output-degraded state regardless of variations in quality, etc., and can extend the service life of the photocoupler. An object of the present invention is to provide a photocoupler device that can be extended. Still another object of the present invention is to provide a photocoupler device capable of predicting and notifying the remaining life of the photocoupler.

  In order to achieve the above object, a photocoupler device according to the present invention includes a first photocoupler subject to deterioration detection, a controller for controlling driving of the first photocoupler, and an output of the first photocoupler. An output detection circuit that generates and outputs a detection value that is a value corresponding to a potential of the signal; and a second photocoupler that transmits the detection value output from the output detection circuit to the controller. The determination unit determines whether or not the first photocoupler is in an output deterioration state based on the detection value when the first photocoupler is driven, and the determination result is k times ( Every time the output is in a degraded state (k is a predetermined value equal to or greater than 2), an adjustment process for increasing the drive current of the first photocoupler is performed.

  According to this configuration, since it is determined whether or not the first photocoupler is in an output deteriorated state based on the detection value that is a value corresponding to the potential of the output signal of the first photocoupler, the quality variation, etc. Regardless of whether or not the first photocoupler is in an output deterioration state, it can be accurately determined. Also, every time the first photocoupler is in an output degradation state, the service life of the first photocoupler is increased by increasing the driving current of the first photocoupler (the current flowing through the light emitting element of the first photocoupler). Can do.

  The display further includes a display controlled by the controller, and the controller displays on the display that the first photocoupler is deteriorated every time the determination result is an output deterioration state. You may be comprised so that it may make. Thereby, preparation for replacement of the first photocoupler can be made in advance.

  Further, when the controller determines that the first photocoupler is in an output deterioration state, the controller predicts a remaining life of the first photocoupler, and predicts the remaining life of the first photocoupler. May be configured to be displayed on the display. This makes it easy for the user to make a schedule for replacement of the first photocoupler (replacement with a new one).

  In this case, the controller includes an actual elapsed time from the start of use of the first photocoupler until the kth determination that the first photocoupler is in an output degradation state, and the first photocoupler. When the first photocoupler is continuously driven, an estimated time that is predetermined as a time from when the first photocoupler starts to be used until the first photocoupler is in an output deterioration state to the kth determination, The remaining life of the first photocoupler is predicted based on an estimated time predetermined as the lifetime of the first photocoupler when one photocoupler is driven continuously. Also good.

  In addition, a plurality of the second photocouplers are provided in parallel between the output detection circuit and the controller, and when the signals transmitted from the respective second photocouplers are different, The display may display that the second photocoupler has deteriorated. Thus, by providing a plurality of second photocouplers in parallel, it is possible to improve the reliability of determining whether or not the first photocoupler is in an output deterioration state. In addition, it is possible to detect deterioration of the second photocoupler.

  In addition, there are a plurality of the first photocouplers controlled by the controller, and the output detection circuit has predetermined potential values of the output signals of the plurality of first photocouplers at predetermined time intervals. The detection values may be generated and output in order, and the controller may be configured to perform the determination process and the adjustment process for each of the first photocouplers. . Thereby, since it is not necessary to provide a plurality of output detection circuits and a plurality of second photocouplers for a plurality of first photocouplers, the circuit configuration can be simplified.

  The present invention has the configuration described above, and in a photocoupler device, it is possible to accurately determine whether or not the photocoupler is in an output deteriorated state regardless of variations in quality, etc., and to increase the service life of the photocoupler. There is an effect that it can be extended. Furthermore, the remaining life of the photocoupler can be notified.

(A) is a figure which shows the example of a circuit structure of the photocoupler apparatus of the 1st Embodiment of this invention, (b) is a figure which shows an example of the variable resistance part of the photocoupler apparatus. (A) is a figure which shows an example of the output signal when the output signal of a photocoupler is a favorable state, and an output deterioration state, (b) is a time-lapse | temporal of the output signal when a photocoupler is on. It is a figure which shows the estimation curve of a static change. It is a figure which shows the circuit structural example of the photocoupler apparatus of the 2nd Embodiment of this invention. It is a figure which shows the circuit structural example of the photocoupler apparatus of the 3rd Embodiment of this invention.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the following description, the same or corresponding elements are denoted by the same reference symbols throughout all the drawings, and redundant description thereof is omitted. The present invention is not limited to the following embodiment.

  In the following embodiments, the photocoupler being degraded corresponds to the photocoupler being in an output degraded state.

(First embodiment)
FIG. 1A is a diagram illustrating a circuit configuration example of the photocoupler device according to the first embodiment of the present invention, and FIG. 1B is a diagram illustrating an example of the variable resistance unit R1 of the photocoupler device. is there.

  In this photocoupler device, the primary side circuit is connected to the primary side high potential side power supply VCC1 and the low potential side power supply GND1, and the secondary side circuit is a secondary having a power supply potential different from that of the primary side. The high potential side power supply VCC2 and the low potential side power supply GND2 are connected to operate. A photocoupler is used to transmit a signal or the like between the primary side circuit and the secondary side circuit. Among these, the photocoupler P1 is a photocoupler that transmits a signal to a secondary circuit (not shown), and is a photocoupler that is subject to deterioration detection.

  On the primary side, the anode of an LED (light emitting diode), which is a light emitting element of the photocoupler P1 subject to degradation detection, is connected to the high potential side power supply VCC1 via the variable resistor R1, and the cathode of the LED is connected to the controller 1A. It is connected to the.

  The controller 1A is composed of, for example, a microcomputer having a CPU and a memory, and controls the display 2 while driving and controlling the photocoupler P1 (on / off control). Information necessary for performing such control is all stored in a memory which is a storage means in the controller 1A, and all information to be stored during control (operation) is also stored in the memory. The display device 2 is constituted by a liquid crystal display, for example.

  On the secondary side, the collector of the phototransistor that is the light receiving element of the photocoupler P1 is connected to the output signal line OUT1 and to the high potential side power supply VCC2 via the load resistor Rf, and the emitter of the phototransistor is low. It is connected to the potential side power supply GND2. Note that the output signal line OUT1 of the photocoupler P1 is connected to a circuit (not shown).

  An output detection circuit 3A that is connected to the output signal line OUT1 and receives the output signal Vo1 is provided. The output detection circuit 3A includes a comparator 31 and a DC power supply 32. An output signal Vo1 of the photocoupler P1 is input to the negative input terminal of the comparator 31, and a constant voltage Vr from the DC power supply 32 is input to the positive input terminal. Entered.

  The output signal Vs of the comparator 31, that is, the output signal Vs of the output detection circuit 3 A, becomes H (high) level when Vo 1 <Vr, and becomes L (low) level when Vo 1 ≧ Vr. , 42.

  The transmission circuits 41 and 42 are circuits for transmitting the output signal Vs of the output detection circuit 3A to the controller 1A, respectively. The transmission circuit 41 includes a photocoupler P21 and resistors R21 and R31. Similarly, the transmission circuit 42 Includes a photocoupler P22 and resistors R22 and R32.

  In the transmission circuit 41, the anode of the LED of the photocoupler P21 is connected to the secondary high-potential power supply VCC2 via the resistor 21, and the cathode of the LED is connected to the low-potential power supply GND2. Further, the collector of the phototransistor of the photocoupler P21 is connected to the primary high potential side power supply VCC1 through the load resistor 31 and to the controller 1A, and the emitter of the phototransistor is connected to the low potential side power supply GND1. It is connected to the. Similarly, in the transmission circuit 42, the photocoupler P22 includes a secondary-side high-potential-side power supply VCC2 and a low-potential-side power supply GND2, a primary-side high-potential-side power supply VCC1 and a low-potential-side power supply GND1, and a controller. 1A.

  For example, as shown in FIG. 1B, the variable resistor R1 includes a resistor R10 connected between the LED of the photocoupler P1 and the power supply VCC1, and a switching element SW1 connected in series in parallel with the resistor R10. The resistor R11, the switching element SW2 and the resistor R12 connected in series, and the switching element SW3 and the resistor R13 connected in series are connected. The on / off states of the switching elements SW1 to SW3 are controlled by control signals CNT1 (CNT11 to CNT13) from the controller 1A, respectively. The resistor R10 is a resistor for initializing the forward current flowing through the LED of the photocoupler P1. For example, when the forward current that flows through the LED of the photocoupler P1 when the switching elements SW1 to SW3 are off is I, the forward current that flows through the LED when one switching element SW1 is turned on is, for example, 1 of I. The forward current that flows through the LED when the two switching elements SW1 and SW2 are turned on is 1.4 times that of I, for example, and the forward current that flows through the LED when the three switching elements SW1 to SW3 are turned on is For example, the resistance values of the resistors R11 to R13 are set to be 1.7 times I.

  The controller 1A determines whether or not the photocoupler P1 has deteriorated based on the signals Vf1 and Vf2 input from the transmission circuits 41 and 42 when the photocoupler P1 is turned on (driven). Each time it is determined that the switching elements SW1, SW2, and SW3 are turned on one by one in this order. By turning on the switching element in this way, the resistance value of the variable resistor R1 is decreased, and the forward current flowing through the light emitting element (LED) of the photocoupler P1, that is, the driving current of the photocoupler P1 is increased.

  The operation of the photocoupler device of the present embodiment configured as described above will be described.

  When the drive control signal IN1 input from the controller 1A to the photocoupler P1 is at H (high) level, the photocoupler P1 is in an off state (a state in which no forward current flows through the LED), and the drive control signal IN1 is L At the (low) level, the photocoupler P1 is in an on state (a state in which a forward current flows through the LED).

  First, when degradation of the photocoupler P1 has never been detected, the switching elements SW1 to SW3 of the variable resistance unit R1 are off, and the LED of the photocoupler P1 is connected to the high potential side power supply VCC1 only through the resistor R10. It is connected.

  In this case, the case where deterioration of the photocoupler P1 is not detected will be described first.

  First, when the drive control signal IN1 from the controller 1A is at H level and the photocoupler P1 is off, the output signal Vo1 of the photocoupler P1 is at H level, and the output signal Vs of the comparator 31 is at L level. At this time, the photocouplers P21 and P22 are off, and the signals Vf1 and Vf2 input to the controller 1A are each at the H level. The voltage Vr of the DC power supply 32 is set so that the potential of the positive input terminal of the comparator 31 is a constant potential that is slightly higher than the potential of the low power supply GND2. For example, when the potential of the high potential side power supply VCC2 is 3.3 to 5V and the potential of the low potential side power supply GND2 is 0V, the voltage Vr is, for example, about 0.5 to 1V.

  Next, when the controller 1A sets the drive control signal IN1 to the L level, the photocoupler P1 is turned on, and the output signal Vo1 of the photocoupler P1 becomes the L level. At this time, the output signal Vs of the comparator 31 becomes H level, the photocouplers P21 and P22 are turned on, and the signals Vf1 and Vf2 input to the controller 1A become L level.

  When the photocoupler P1 is turned on, the controller 1A compares the potential of the output signal Vf1 of the photocoupler P21 and the potential of the output signal Vf2 of the photocoupler P21 with a predetermined level determination value, and outputs two output signals. If the potentials of Vf1 and Vf2 are less than the level determination value, the two output signals Vf1 and Vf2 are recognized as L level, and if they are equal to or higher than the level determination value, they are recognized as H level. The level determination value may be an intermediate value between the potential of the primary high-potential power supply VCC1 and the potential of the low-potential power supply GND1, for example, half of the sum of both potentials.

  Next, a case where deterioration of the photocoupler P1 is detected will be described. FIG. 2A is a diagram illustrating an example of the output signal Vo1 when the output signal Vo1 of the photocoupler P1 is in a good state and when it is not good and the deterioration is detected (output deterioration state). In the figure, VCC2 indicates the potential of the secondary high-potential power supply VCC2, and GND2 indicates the potential of the secondary low-potential power supply GND2. FIG. 2B is a diagram showing an estimated curve of the change over time of the output signal Vo1 when the photocoupler P1 is on, and the horizontal axis shows the continuous drive time or accumulated drive time of the photocoupler P1. Show. The estimated curve L1 is an estimated curve when all of the switching elements SW1 to SW3 of the variable resistance unit R1 are off, and the resistance value of the variable resistance unit R1 is a resistance value only by the resistor R10. In the estimated curve L1, Vo1 The curve L2 is an estimated curve when the switching element SW1 is turned on when is at the potential Vr (time t1). Further, in the estimated curve L2, when Vo1 is the potential Vr (time t2), the estimated curve when the switching element SW2 is turned on is the curve L3. Further, in the estimated curve L3, when Vo1 is the potential Vr (time t3), the switching element The estimated curve when SW3 is turned on is the curve L4.

  When the deterioration of the photocoupler P1 is detected, when the controller 1A sets the drive control signal IN1 to the L level, the photocoupler P1 is turned on, and the output signal Vo1 of the photocoupler P1 becomes the pseudo L level. Here, the pseudo L level is, for example, a state where Vo1 becomes Vr or slightly larger than Vr as shown in the output deterioration state of FIG. At this time, the output signal Vs of the comparator 31 does not change from the same L level as when the photocoupler P1 is off, the photocouplers P21 and P22 remain off, and the signals Vf1 and Vf2 input to the controller 1A are also respectively. It remains at the H level.

  When the drive control signal IN1 is set to L level, that is, when the photocoupler P1 is turned on, the controller 1A changes the levels of the output signals Vf1 and Vf2 of the two photocouplers P21 and P22 from H level to L level. If it is not changed to the L level and remains at the H level, it is determined that the photocoupler P1 has deteriorated (deterioration of the photocoupler P1 is detected), and the variable resistor R1, for example, The switching element SW1 is turned on. As a result, the forward current of the LED of the photocoupler P1 can be increased, and when the photocoupler P1 is turned on, the output signal Vo1 of the photocoupler P1 can be recovered to a desired L level (eg, 0 V). .

  As described above, the controller 1A turns on the switching element SW1 of the variable resistor unit R1 when the first detection of deterioration of the photocoupler P1 is detected, and further switches when the detection of deterioration is the second time. When the element SW2 is turned on and the deterioration is detected for the third time, the switching element SW3 is further turned on.

  Further, when the controller 1A detects the deterioration of the photocoupler P1, the controller 1A displays a message to that effect on the screen of the display 2. At this time, the message may be changed according to the number of times the deterioration is detected. For example, if degradation is detected for the first time, the message “Photocoupler is degraded. Please prepare for replacement.” Is displayed. If degradation is detected for the second time, “Photo When the message “The coupler is deteriorating. Replace it.” Is displayed and the degradation is detected for the third time, “The photocoupler is very degraded. Replace it soon.” If a message is displayed and deterioration is detected for the fourth time, the message “Photocoupler is about to fail. Replace it immediately.” Is displayed.

  Further, when the photocoupler P1 is turned on, the controller 1A compares the potential of the output signal Vf1 of the photocoupler P21 with the potential of the output signal Vf2 of the photocoupler P21, and the potentials of the two output signals Vf1 and Vf2. If the difference between the two output signals Vf1 and Vf2 is equal to or less than the predetermined value x stored in advance, it is determined that the two output signals Vf1 and Vf2 match. It is determined that the two output signals Vf1 and Vf2 do not match, that is, are different. When it is determined that the two output signals Vf1 and Vf2 are different, it is determined that any one of the photocouplers P21 and P22 has deteriorated, and a message for informing the fact is displayed on the display 2. Further, when it is determined that the two output signals Vf1 and Vf2 are different, it is determined that the photocoupler that outputs the higher potential is deteriorated, and a message notifying that is displayed on the display 2. Also good. For example, when it is determined that the photocoupler P21 is the first photocoupler of the detection circuit and the photocoupler P22 is the second photocoupler of the detection circuit, and it is determined that the photocoupler P21 has deteriorated, “ The message “No. 1 photocoupler in the detection circuit has deteriorated. Replace it” is displayed on the display unit 2.

  In the present embodiment, since it is determined whether or not the photocoupler P1 has deteriorated based on the output signal Vs of the output detection circuit 3A output according to the potential of the output signal Vo1 of the photocoupler P1, the photocoupler It is possible to accurately determine the deterioration of the photocoupler P1 regardless of the quality variation of the photocoupler. Further, every time the deterioration of the photocoupler P1 is detected, the resistance value of the variable resistor R1 is decreased to increase the forward current flowing through the LED of the photocoupler P1, thereby reducing the use period (service life) of the photocoupler P1. Can be extended.

  Further, since the output signal Vs of the output detection circuit 3A is transmitted to the controller 1A by the plurality of transmission circuits 41 and 42, the reliability of the deterioration determination of the photocoupler P1 can be improved. Three or more such transmission circuits may be provided.

  In addition, by notifying the deterioration of the photocoupler P1, the user can prepare a replacement photocoupler in advance.

(Second Embodiment)
FIG. 3 is a diagram showing a circuit configuration example of the photocoupler device according to the second embodiment of the present invention. The same parts as those in FIG. 1A are denoted by the same reference numerals, and detailed description thereof is omitted.

  In this embodiment, a significant difference from the first embodiment is that an AD (analog-digital) converter 3B is provided as an output detection circuit in place of the output detection circuit 3A. The AD converter 3B samples the output signal Vo1 of the photocoupler P1 subject to deterioration detection at every predetermined time, converts it into a digital signal SD1, and serially outputs it. The transmission circuits 41 and 42 have the same configuration as in the first embodiment.

  The controller 1B is configured by, for example, a microcomputer having a CPU, a memory, and the like similarly to the controller 1A described above, and controls the display 2 while driving and controlling the photocoupler P1 (on / off control). Information necessary for performing such control is all stored in a memory which is a storage means in the controller 1B, and all information to be stored during control (operation) is also stored in the memory. As will be described later, part of the processing is different from that of the controller 1A.

  The operation of the photocoupler device of the present embodiment configured as described above will be described.

  When the drive control signal IN1 input from the controller 1B to the photocoupler P1 is at H (high) level, the photocoupler P1 is off, and when the drive control signal IN1 is at L (low) level, the photocoupler P1 is on. It is.

  First, when degradation of the photocoupler P1 has never been detected, the switching elements SW1 to SW3 of the variable resistance unit R1 are off, and the LED of the photocoupler P1 is connected to the high potential side power supply VCC1 only through the resistor R10. They are connected (see FIG. 1B).

  In this case, the case where deterioration of the photocoupler P1 is not detected will be described first.

  The potential of the output signal Vo1 of the photocoupler P1 is converted into a digital signal SD1 every predetermined time by the AD converter 3B and serially output. The digital signal SD1 is input to the controller 1B through the photocouplers P21 and P22 as signals SD11 and SD12 corresponding to the digital signal SD1. Here, the value of the potential of the output signal Vo1 is serially output from the AD converter 3B as a digital signal SD1, and values obtained by inverting the values of the serially output bits are output to the controller 1B as digital signals SD11 and SD12. Since it is input, the controller 1B obtains the potential (m) of the output signal Vo1 of the photocoupler P1 by inverting the value of each bit of the input digital signals SD11 and SD12.

  In the controller 1B, when the drive control signal IN1 is set to L level and the photocoupler P1 is turned on, the potential m of the output signal Vo1 of the photocoupler P1 obtained from the input digital signals SD11 and SD12 is set to a predetermined value Vr ( Vr is compared with a value corresponding to Vr in the first embodiment, and is determined to be normal when m <Vr, and is determined that photocoupler P1 has deteriorated when m ≧ Vr (of photocoupler P1) For example, the switching element SW1 of the variable resistance portion R1 is turned on when it is determined that the deterioration has occurred. Thereby, the forward current of the LED of the photocoupler P1 can be increased, and when the photocoupler P1 is turned on, the output signal Vo1 of the photocoupler P1 can be recovered to a desired L level.

  The controller 1B turns on the switching element SW1 of the variable resistance unit R1 when the first detection of deterioration of the photocoupler P1 is detected, and further turns on the switching element SW2 when the detection of deterioration is the second time. When the detection of deterioration is the third time, the switching element SW3 is further turned on.

  Further, similarly to the controller 1A in the first embodiment, when the controller 1B detects the deterioration of the photocoupler P1, the controller 1B displays a message informing that effect on the display 2.

  In addition, when the photocoupler P1 is turned on, the controller 1B includes two photocouplers for the bit indicating L level “0” in the digital signals SD11 and SD12 input from the two photocouplers P21 and P22. The potentials of the output signals of P21 and P22 are compared, and if the difference between the potentials of the two output signals is less than a predetermined value x stored in advance, it is determined that the two output signals match, and the two output signals If the potential difference between the two output signals is equal to or greater than the predetermined value x, the two output signals are determined not to match, that is, different, and when determined to be different, it is determined that one of the photocouplers P21, P22 has deteriorated, A message notifying that is displayed on the display 2. Further, when it is determined that the two output signals are different, it is determined that the photocoupler that outputs the higher potential is deteriorated, and a message notifying that is displayed on the display 2. Good.

  Further, when the controller 1B detects the deterioration of the photocoupler P1, the controller 1B predicts the life or remaining life of the photocoupler P1, and displays the predicted value on the display 2 together with a message informing the deterioration of the photocoupler P1. Let For example, “the life of a photocoupler will end in 0.00 years” is displayed, or “the remaining life of a photocoupler is another 00 days”.

  A life prediction method using the controller 1B will be described. Here, the controller 1B stores in advance the times t1, t2, t3, and t4 during which the estimated curves L1, L2, L3, and L4 shown in FIG. These times t1, t2, t3, and t4 are input by the input means 5. Further, the controller 1B has a clock function such as a real-time clock, and stores the use start time of the photocoupler P1. For example, when the present photocoupler device is used for the first time, the time t1, t2, t3, t4 is input to the controller 1B by the input means 5. The controller 1B stores the time (time and date at that time) when these times t1, t2, t3, and t4 are input as the use start time of the photocoupler P1. In addition, when the photocoupler P1 is replaced, a signal indicating that the photocoupler P1 has been replaced is input to the controller 1B. The point in time (the date and time at that time) is stored as the use start point of the photocoupler P1. For example, the input means 5 is configured as a touch screen type operation display together with the display 2, and the above-described times t1, t2, t3, t4 and the photocoupler P1 are replaced by the user operating the operation display. It is configured to be able to input a signal to that effect.

  Each time the controller 1B detects the deterioration of the photocoupler P1, the controller 1B calculates a time (deterioration detection time) Tk from the start of use of the photocoupler P1 to the time when it is determined that the photocoupler P1 is deteriorated. Calculate the remaining life. For example, if the deterioration detection time when detecting the k-th deterioration (k = 1, 2, 3 in this embodiment) is Tk, the remaining life Tx is calculated by the following equation.

Tx = (Tk / tk) × t4−Tk
Here, tk (k = 1, 2, 3) and t4 are the times t1, t2, t3, and t4 shown in FIG. 2B stored in advance.

For example, when the deterioration of the photocoupler P1 is detected for the first time, the time (deterioration detection time) T1 from the start of use of the photocoupler P1 to the time when the deterioration is detected for the first time is calculated, and the remaining life Tx is calculated by
Tx = (T1 / t1) × t4-T1
Calculate as That is, the estimated curves L1 to L4 in FIG. 2B have a continuous drive time or a cumulative drive time that does not take into account the time when the photocoupler P1 is off as a horizontal axis, and thus (T1 / t1) × t4. Is the predicted time from the start of use until the fourth deterioration is detected in the actual use situation. In this embodiment, this predicted time is the life of the photocoupler P1. Here, tk (k = 1, 2, 3) is an estimated time set in advance as the time from when the photocoupler P1 is continuously driven until when it is determined that the output is in a degraded state. , T4 is an estimated time predetermined as the lifetime of the photocoupler P1 when the photocoupler P1 is continuously driven.

  In the present embodiment, the same effect as in the first embodiment can be obtained. Further, since the remaining life of the photocoupler P1 can be predicted and notified, the user can easily make a schedule for replacement (replacement with a new one) of the photocoupler P1.

(Third embodiment)
FIG. 4 is a diagram showing a circuit configuration example of the photocoupler device according to the third embodiment of the present invention. The same parts as those in FIGS. 1A and 3 are denoted by the same reference numerals, and detailed description thereof is omitted. To do.

  In this embodiment, the major difference from the second embodiment is that a plurality of photocouplers are targeted for deterioration detection. Among the photocouplers P1 to Pn (n is an integer equal to or greater than 3), a plurality of photocouplers P1 to P (n-1) are the original degradation detection target photocouplers, and these output signal lines OUT1 to OUT (n -1) is connected to a secondary circuit (not shown).

  In each of the photocouplers P1 to Pn, the anode of the LED is connected to the high potential side power supply VCC1 via the variable resistor portion R1 in the same manner as the photocoupler P1 in the first and second embodiments, and the cathode Is connected to the controller 1C. The collector of the phototransistor is connected to each of the output signal lines OUT1 to OUTn, is connected to the high potential side power supply VCC2 via the load resistor Rf, and the emitter is connected to the low potential side power supply GND2. Each variable resistance part R1 of the photocouplers P1 to Pn is configured as shown in FIG. 1B, for example, similarly to the variable resistance part R1 of the photocoupler P1 in the first and second embodiments. ON / OFF of the switching elements SW1 to SW3 of the variable resistance unit R1 is controlled by control signals CNT1 to CNTn from the controller 1C.

  And the output detection circuit 3C provided with AD converter 33 and the controller 34 is provided. The AD converter 33 is connected to the output signal lines OUT1 to OUTn of the photocouplers P1 to Pn, and the output signal line OUTn of the photocoupler Pn is also connected to the controller 34. The photocoupler Pn is provided in order to give the synchronization pulse from the controller 1C to the controller 34. In the present embodiment, the photocoupler Pn is included in the photocoupler subject to deterioration detection. The controller 1C turns on the photocoupler Pn every predetermined time (predetermined fixed time), thereby setting the output signal Von to L level every predetermined time, and this L level synchronization pulse (hereinafter referred to as “synchronization”). (Referred to as “pulse VonL”).

  The AD converter 33 converts the output signals Vo1 to Von of the photocouplers P1 to Pn to be subjected to deterioration detection into digital signals and serially outputs them to the controller 34. The controller 34 causes the AD converter 33 to perform the above operation every time the synchronization pulse VonL is input every predetermined time, and serially outputs the digital signal SD2 input from the AD converter 33 to the transmission circuits 41 and 42. . The transmission circuits 41 and 42 have the same configuration as in the first and second embodiments.

  The controller 1C is configured by, for example, a microcomputer having a CPU, a memory, and the like, and controls the display 2 while driving and controlling the photocouplers P1 to Pn (on / off control). Information necessary for performing such control is all stored in a memory which is a storage means in the controller 1C, and all information to be stored during control (operation) is also stored in the memory. Further, numbers are assigned in advance to the photocouplers P1 to Pn, and the controller 1C stores the numbers.

  The operation of the photocoupler device of the present embodiment configured as described above will be described.

  When the drive control signals IN1 to INn input from the controller 1C to the photocouplers P1 to Pn are at H (high) level, the photocouplers P1 to Pn are off, and the drive control signals IN1 to INn are at L (low) level. At this time, the photocouplers P1 to Pn are on. Note that the timing of turning on / off each of the photocouplers P1 to Pn may be different, or some of them may be turned on / off simultaneously.

  First, when the deterioration of the photocouplers P1 to Pn has not been detected, the switching elements SW1 to SW3 of the respective variable resistance units R1 are off, and the LEDs of the respective photocouplers P1 to Pn have only the resistance R10. To the high potential side power supply VCC1 (see FIG. 1B).

  In this case, a case where deterioration of the photocouplers P1 to Pn is not detected will be described first.

  The potentials of the output signals Vo1 to Von of the photocouplers P1 to Pn are simultaneously taken into the AD converter 33 by the control of the controller 34 every time the synchronization pulse VonL is input to the controller 34, The signals are sequentially converted into digital signals, serially output to the controller 34, and further serially output from the controller 34 as a digital signal SD2. That is, the potentials of the output signals Vo1 to Von of the photocouplers P1 to Pn are serially output in a predetermined order as the digital signal SD2. The digital signal SD2 is input to the controller 1C as the signals SD21 and SD22 corresponding to the digital signal SD2 via the photocouplers P21 and P22.

  In the controller 1C, the potentials m1 to mn of the output signals Vo1 to Von of the respective photocouplers P1 to Pn from the input digital signals SD21 and SD22, and the controller 1B in the second embodiment to the potential m of the output signal Vo1. As in the case of the second embodiment, the potential of the output signal of the photocoupler that is turned on among the photocouplers P1 to Pn is set to the predetermined value Vr (Vr is the first embodiment). And a value connected to the photocoupler when it is determined that the photocoupler is deteriorated (deterioration is detected). For example, the switching element SW1 of the resistor R1 is turned on. Similarly, when the second detection of deterioration of the photocoupler is detected, the switching element SW2 is further turned on, and when the detection of deterioration is the third time, the switching element SW3 is further turned on.

  Further, similarly to the controller 1A in the first embodiment, when the controller 1C detects deterioration of any one of the photocouplers P1 to Pn, for example, the photocoupler is deteriorated. A message notifying the effect is displayed on the display 2. Here, in this embodiment, since there are a plurality of photocouplers to be detected for deterioration, the number of the photocoupler determined to be deteriorated is also displayed.

  Furthermore, when the controller 1C detects the deterioration of any one of the photocouplers P1 to Pn, the controller 1C determines the life or remaining life of the photocoupler determined to be deteriorated in the second embodiment. The controller 1B predicts the life or remaining life of the photocoupler P1 in the same manner as the case, and the predicted value is displayed on the display 2 together with a message informing the photocoupler of deterioration. That is, for each of the photocouplers P1 to Pn, the controller 1C calculates the times t1, t2, t3, and t4 when the estimated curves L1, L2, L3, and L4 shown in FIG. Pre-stored. Further, the controller 1C has a clock function such as a real-time clock, and stores the use start time of each of the photocouplers P1 to Pn. The times t1, t2, t3, t4 and the use start time for each photocoupler are stored in the controller 1C in the same manner as in the second embodiment. Each time the controller 1C detects the deterioration of the individual photocouplers P1 to Pn, the controller 1C calculates the time (deterioration detection time) Tk from the start of use of the photocoupler where the deterioration is detected to the time when the deterioration is detected. The remaining life is calculated based on the calculation. The calculation method of the remaining lifetime of each photocoupler is the same as the calculation method of the remaining lifetime of the photocoupler P1 in the second embodiment.

  Further, the controller 1C compares the potentials of the output signals of the two photocouplers P21 and P22 in the same manner as the controller 1B in the second embodiment, and determines whether the two output signals match or differ. If it is determined that they are different from each other, a message notifying that one of the photocouplers P21 and P22 has deteriorated is displayed on the display 2. Further, as described in the second embodiment, it may be determined which one of the photocouplers P21 and P22 has deteriorated, and display that effect on the display 2.

  In the present embodiment, the same effect as in the second embodiment can be obtained. Furthermore, since only one voltage detection circuit 3C and a pair of transmission circuits 41 and 42 need to be provided for a plurality of photocouplers whose deterioration is to be detected, the circuit configuration can be simplified. If the AD converter 33 is configured to recognize and operate based on the synchronization pulse VonL, the controller 34 can be eliminated.

  In the first to third embodiments, the change of the resistance value in the variable resistor portion R1 (that is, the change of the driving current of the photocoupler) can be performed three times, but can be performed twice or four times or more. You may do it. Further, a digital potentiometer, which is a variable resistor that can be controlled by a digital signal, may be used for the variable resistor R1.

  INDUSTRIAL APPLICABILITY The present invention is useful as a photocoupler device that can accurately determine the output degradation state of a photocoupler regardless of quality variations and the like and can extend the service life of the photocoupler.

P1 to Pn Photocoupler P21 to P22 Photocoupler R1 Variable resistance unit 1A to 1C Controller 2 Display 3A Output detection circuit 3B AD converter 3C Output detection circuit

Claims (6)

A first photocoupler to be detected for deterioration;
A controller for controlling the driving of the first photocoupler;
An output detection circuit that generates and outputs a detection value that is a value corresponding to the potential of the output signal of the first photocoupler;
A second photocoupler that transmits the detection value output from the output detection circuit to the controller;
The controller is
Based on the detection value when the first photocoupler is driven, a determination process is performed to determine whether or not the first photocoupler is in an output deterioration state. This determination result is k times (k is 2). A photocoupler device configured to perform an adjustment process to increase the drive current of the first photocoupler every time the output deteriorates to the predetermined value). Further comprising a display controlled by the controller;
2. The photocoupler according to claim 1, wherein the controller is configured to display on the display that the first photocoupler is deteriorated each time the determination result is an output deterioration state. apparatus. The controller is
When it is determined that the first photocoupler is in an output deterioration state, the remaining lifetime of the first photocoupler is predicted, and the predicted remaining lifetime of the first photocoupler is displayed on the display. The photocoupler device according to claim 2, configured as described above. The controller is
When the first photocoupler starts to be used and the first photocoupler is in an output deterioration state, the actual elapsed time from the determination of the kth time, and when the first photocoupler is driven continuously If the first photocoupler is in an output deterioration state from the start of use of the first photocoupler, an estimated time predetermined as a time from the determination of the kth time to the first photocoupler, and the first photocoupler continuously 4. The photocoupler according to claim 3, configured to predict a remaining life of the first photocoupler based on a predetermined estimated time as a life of the first photocoupler when driven. 5. apparatus. A plurality of the second photocouplers are provided in parallel between the output detection circuit and the controller,
The controller is configured to cause the display to display that the second photocoupler has deteriorated when signals transmitted from the second photocouplers are different from each other. The photocoupler device according to 2. A plurality of the first photocouplers controlled by the controller;
The output detection circuit includes:
A plurality of first photocoupler output signal potential values are generated and output as the detection values in a predetermined order at predetermined time intervals;
The photocoupler device according to claim 1, wherein the controller is configured to perform the determination process and the adjustment process for each of the first photocouplers.

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