JP6829026B2 - measuring device - Google Patents

Description

The present invention relates to a measuring device for measuring a resistance, a capacitor, and a diode as measurement targets.

As an example of this type of measuring device, the applicant of the present application has already proposed a measuring device (multimeter) disclosed in Patent Document 1 below. This measuring device includes a rotary switch for selecting one of a plurality of measuring functions (resistance measuring function, capacitor measuring function and diode measuring function), and the measuring function selected by the user's operation on the rotary switch. Based on the above, it is configured so that the measured amount of the connected measurement target can be measured.

Japanese Unexamined Patent Publication No. 2014-10007 (Pages 2-5, Fig. 1)

However, the above-mentioned measuring device has the following problems to be improved. That is, since the user operates the rotary switch to select the measurement function in this measuring device, a situation may occur in which the selected measurement function and the measurement target do not match due to a human error. In this case, there is a problem to be improved that it is necessary to operate the rotary switch again to reselect the measurement function that matches the measurement target (that is, the measurement target).

The present invention has been made to improve such a problem, and an object of the present invention is to provide a measuring device capable of reliably selecting a measuring function that matches a measured quantity.

In order to achieve the above object, the measuring device according to claim 1 is between a pair of input terminals, a voltage detection unit that outputs voltage data indicating a voltage between the pair of input terminals, and the pair of input terminals. The voltage value of the voltage between the terminals is measured based on the voltage data output from the voltage detection unit and the current supply unit capable of supplying a constant current, and between the pair of input terminals. When the measurement target connected to is a diode, the forward voltage of the diode is measured as the measured quantity based on the measured voltage value, and the measurement target connected between the pair of input terminals is a resistor or capacitor. Occasionally, it is provided with a processing unit that executes a measured amount measurement process that measures the resistance value of the resistor or the capacitance value of the capacitor as the measured amount based on the measured voltage value and the current value of the constant current . wherein the processing unit is a measurement apparatus that performs a specific process in which the measurement object that is connected between the pair of input terminals to identify whether a capacitor whether a diode resistor, said pair of input An AC voltage supply unit capable of supplying an AC constant voltage between the terminals is provided, and the processing unit is one of the AC constant voltage of the voltage data output from the voltage detection unit in the state of supplying the AC constant voltage. Whether or not the measurement target is a diode based on whether or not the integrated value is calculated for the voltage data included in the predetermined first phase range centered on one zero crossing point and the integrated value is almost zero. The first specific process as the specific process for specifying the above is executed .

The measuring device according to claim 2 includes an alternating current supply unit capable of supplying an alternating current between the pair of input terminals in the measuring device according to claim 1 , and the processing unit does not measure the measurement target with a diode. When specified, the voltage included in a predetermined second phase range centered on one zero cross point of the AC constant current in the voltage data output from the voltage detection unit in the AC constant current supply state. The second specific process as the specific process for specifying whether the measurement target is a resistor or a capacitor is executed based on whether or not the integrated value is almost zero while calculating the integrated value for the data. ..

In the measuring device according to claim 1, the processing unit executes a specific process to specify whether the connected measurement target is a diode, a resistor, or a capacitor. Therefore, according to this measuring device, it is possible to reliably select a measurement function that matches the measured quantity to be measured based on the result of the specific processing, and to reliably measure the measured quantity.

Further, according to the measuring apparatus of this, for the configuration of calculating the integrated value of the voltage data contained in the first phase range of the voltage data outputted from the voltage detector in the supply state of the AC constant voltage, process Each time a unit acquires voltage data from the voltage detection unit, it is included in the first phase range because it can adopt a method of calculating the integrated value up to this voltage data by adding this voltage data to the integrated value up to that point. Compared with the configuration in which the integrated value of all voltage data is calculated after all of the plurality of voltage data are acquired, the memory capacity for storing the voltage data can be significantly reduced, whereby the measuring device can be manufactured at low cost. be able to.

According to the measuring device according to claim 2 , the integrated value of the voltage data included in the second phase range of the voltage data output from the voltage detection unit in the supply state of the AC constant current is calculated. Each time the processing unit acquires voltage data from the voltage detection unit, it can adopt a method of calculating the integrated value up to this voltage data by adding this voltage data to the integrated value up to that point, so it is in the second phase range. Compared to a configuration in which the integrated value of all voltage data is calculated after acquiring all of the included multiple voltage data, the memory capacity for storing the voltage data can be significantly reduced, which makes the measuring device inexpensive. can do.

It is a block diagram of the measuring apparatus 1. It is a flowchart for demonstrating the operation of the measuring apparatus 1. It is a waveform diagram for demonstrating the operation in the 1st specific processing in FIG. It is another waveform diagram for demonstrating the operation in the 1st specific processing in FIG. It is another waveform diagram for demonstrating the operation in the 1st specific processing in FIG. It is a waveform diagram for demonstrating the operation in the 2nd specific processing in FIG. It is another waveform diagram for demonstrating the operation in the 2nd specific processing in FIG. It is another waveform diagram for demonstrating the operation in the 2nd specific processing in FIG.

Hereinafter, embodiments of the measuring device will be described with reference to the accompanying drawings.

First, the configuration of the measuring device 1 as the measuring device will be described with reference to the drawings.

As shown in FIG. 1, the measuring device 1 includes a pair of input terminals 2 and 3, an AC voltage supply unit 4, an AC current supply unit 5, a DC current supply unit 6, a switching unit 7, a voltmeter 8, and a discharge unit 9. For the measurement target 100 provided with the processing unit 10 and the output unit 11 and connected between the pair of input terminals 2 and 3, it is automatically specified whether it is a diode, a resistor, or a capacitor. At the same time, the measured amount of the specified measurement target 100 (voltage value Vf of forward voltage when the specified measurement target 100 is a diode, resistance value R when it is a resistor, and capacitance value C when it is a capacitor) can be automatically measured. It is configured in. Further, the measuring device 1 generates an operating voltage for operating each component such as the AC voltage supply unit 4 to the output unit 11 described above with reference to a reference potential (potential of the internal ground G), which is not shown. It has a part. One of the input terminals 2 and 3 (in this example, the input terminal 2 as an example) is connected to the internal ground G. When a diode is connected between the input terminals 2 and 3 as the measurement target 100, the anode terminal is connected to the input terminal 3 and the cathode terminal is connected to the input terminal 2.

The AC voltage supply unit 4 is composed of, for example, an AC constant voltage source, has a predetermined constant voltage value (constant amplitude: known), and has a constant period T1 (known) AC voltage (AC constant voltage). ) V1 is generated as a sinusoidal voltage with the internal ground G as a reference potential under the control of the processing unit 10, and can be output to the switching unit 7 from an output terminal (not shown). Further, when the AC voltage supply unit 4 outputs the AC voltage V1, the zero cross point of the AC voltage V1 (one of the rising zero crossing point and the falling zero crossing point. In this example, the rising zero crossing point is an example. ), A trigger signal St1 is generated and output to the processing unit 10. Further, the AC voltage supply unit 4 has a current limiting function for preventing the current value of the output current output from the output terminal from exceeding the upper limit value of its own output voltage.

The AC current supply unit 5 is composed of, for example, an AC constant current source, has a predetermined constant current value (constant amplitude: known), and has a constant period T1 (in this example, an AC voltage V1 as an example). An alternating current (alternating current) I1 having the same period but different from the alternating current voltage V1 if known is generated as a sinusoidal current under the control of the processing unit 10 and is not shown. It is configured so that it can be output from the output terminal of the above to the switching unit 7. Further, when the AC current supply unit 5 outputs the AC current I1, the zero cross point of the AC current I1 (one of the rising zero crossing point and the falling zero crossing point. In this example, the rising zero crossing point is an example. ), A trigger signal St2 is generated and output to the processing unit 10. Further, the AC current supply unit 5 has a voltage limiting function for preventing the voltage value of the output voltage generated in the output terminal for the output of the AC current I1 from exceeding the upper limit value of its own output voltage. ing.

The DC current supply unit 6 is composed of, for example, a DC constant current source, and generates a DC current (DC constant current) I2 having a predetermined constant current value I2a (known) under the control of the processing unit 10. It is configured so that it can be output as a step signal from an output terminal (not shown) to the switching unit 7.

The switching unit 7 is configured to include, for example, a plurality of switches such as relays and semiconductor switches, and includes an AC voltage supply unit 4, an AC current supply unit 5, a DC current supply unit 6, and the other of the input terminals 2 and 3. (In this example, it is arranged between the input terminal 3 as an example). Further, in the switching unit 7, the processing unit 10 controls the on / off state of each switch (that is, the switching state of the switching unit 7), so that the AC voltage supply unit 4, the AC current supply unit 5, and the DC current supply unit 7 are controlled. One selected output terminal from each output terminal of unit 6 is connected to the input terminal 3. With this configuration, the switching unit 7 can supply a selected one of the AC voltage V1, the AC current I1 and the DC current I2 to the input terminal 3 (that is, between the input terminals 2 and 3). ..

As an example, the voltmeter 8 is composed of a digital sampling type voltmeter and functions as a voltage detection unit, and is generated at the input terminal 3 with the input terminal 2 as a reference (that is, with reference to the potential of the internal ground G). By inputting the inter-terminal voltage V2 with a high input impedance and sampling at a predetermined sampling period (a period sufficiently shorter than the period T1 of the AC voltage V1 and the AC current I1 described above), the inter-terminal voltage V2 The voltage data Dv indicating the instantaneous value is generated and output to the processing unit 10.

The discharge unit 9 includes, for example, a switch (not shown) whose on / off state can be controlled by the processing unit 10 and a discharge resistor (load) (not shown) connected in series to the switch, and the input terminals 2 and 2. It is connected between three. With this configuration, when this switch is controlled to be in the ON state, the discharge unit 9 uses a discharge resistor connected between the pair of input terminals 2 and 3, for example, as a measurement target 100 between the input terminals 2 and 3. It is possible to discharge the electric charge stored in the connected capacitor. On the other hand, in the discharge unit 9, when this switch is controlled to the off state, the connection of the discharge resistor between the pair of input terminals 2 and 3 is released.

The processing unit 10 is configured to include, for example, a CPU and a memory (none of which are shown) for the AC voltage supply unit 4, the AC current supply unit 5, the DC current supply unit 6, the switching unit 7, and the discharge unit 9. Execute control processing. Further, the processing unit 10 executes the measurement process 50 shown in FIG. Further, the processing unit 10 executes an output process of outputting the measurement result of the measurement process 50 to the output unit 11. Further, in the memory of the processing unit 10, the first start time ts1 corresponding to the first start phase that defines the start of the predetermined first phase range used in the first specific process described later executed in the measurement process 50 and It corresponds to the first end time te1 corresponding to the first end phase that defines the end of the first phase range, and the second start phase that defines the start of a predetermined second phase range used in the second specific process described later. The second start time ts2 and the second end time te2 corresponding to the second end phase that defines the end of the second phase range are stored in advance.

In this case, the first phase range is ± a degree centered on one zero cross point of the AC voltage V1 in the state where the AC voltage V1 is output from the AC voltage supply unit 4 (the supply state of the AC voltage V1). (A is a predetermined value within the range of 45 or more and 180 or less). In this example, as an example, the value a is defined as "90", and this zero cross point is the zero cross point next to the zero cross point at the timing when the AC voltage supply unit 4 outputs the trigger signal St1. Therefore, at the zero cross point for defining the first phase range, the AC voltage supply unit 4 rises as described above in this example and outputs the trigger signal St1 in synchronization with the zero cross point P1 (see FIG. 3 and the like). Therefore, it becomes the next zero cross point (that is, the next falling zero cross point P2) after the rising zero cross point P1. Therefore, when the phase of the rising zero cross point P1 is 0 degrees, the phase of the falling zero cross point P2 is 180 degrees, so that the first phase range is the phase of ± 90 degrees centered on this 180 degree phase. It is defined as a range (that is, a phase range of 90 degrees or more and 270 degrees or less when the phase of the rising zero cross point P1 is 0 degrees).

In the supply state of the AC voltage V1, the processing unit 10 sets the voltage data Dv included in the first phase range of the voltage data Dv output from the voltmeter 8 at the first start time ts1 and the first end. Cut out and obtain using time te1. Therefore, in the measuring device 1, the processing unit 10 measures the elapsed time from the input time of the trigger signal St1, and when this elapsed time reaches the first start time ts1, the start of the first phase range arrives. The first start time ts1 is based on one cycle T1 of the AC voltage V1 so that it can be determined that the end of the first phase range has arrived when the elapsed time reaches the first end time te1. Is defined as T1 × 90/360, and the first end time te1 is defined as T1 × 270/360.

The second phase range is ± b degrees around one zero cross point of the AC current I1 in a state where the AC current I1 is output from the AC current supply unit 5 (supply state of the AC current I1). b is a predetermined value within the range of 45 or more and 90 or less). In this example, as an example, the value b is defined as "90", and this zero cross point is the zero cross point next to the zero cross point at the timing when the AC current supply unit 5 outputs the trigger signal St2. Therefore, at the zero cross point for defining the second phase range, the AC current supply unit 5 rises as described above in this example and outputs the trigger signal St2 in synchronization with the zero cross point P3 (see FIG. 6 and the like). Therefore, it becomes the next zero cross point (that is, the next falling zero cross point P4) after the rising zero cross point P3. Therefore, when the phase of the rising zero cross point P3 is 0 degrees, the phase of the falling zero cross point P4 is 180 degrees, so that the second phase range is the phase of ± 90 degrees centered on this 180 degree phase. It is defined as a range (that is, a phase range of 90 degrees or more and 270 degrees or less when the phase of the rising zero cross point P3 is 0 degrees).

In the supply state of the alternating current I1, the processing unit 10 uses the voltage data Dv included in the second phase range of the voltage data Dv output from the voltmeter 8 as the second start time ts2 and the second end. Cut out and obtain using time te2. Therefore, in the measuring device 1, the processing unit 10 measures the elapsed time from the input time of the trigger signal St2, and when this elapsed time reaches the second start time ts2, the start of the second phase range arrives. The second start time ts2 is based on the one cycle T1 of the AC current I1 so that it can be determined that the end of the second phase range has arrived when this elapsed time reaches the second end time te2. Is defined as T1 × 90/360, and the second end time te2 is defined as T1 × 270/360.

As an example, the output unit 11 is composed of a display device such as an LCD, inputs a measurement result output from the processing unit 10, and displays it on a screen. The output unit 11 may be configured by various interface circuits instead of the display device. For example, the output unit 11 may be stored in a removable media as a media interface circuit, or may be stored in an external device via a network as a network interface circuit. It is also possible to adopt a configuration in which the measurement result is transmitted.

Next, the operation of the measuring device 1 will be described with reference to the drawings.

In the measuring device 1, in a state where the measurement target 100 is connected between the input terminals 2 and 3, the processing unit 10 first executes control on the discharge unit 9 and turns off the switch of the discharge unit 9 as an initial state. After shifting from the state to the on state, it shifts to the off state again. As a result, the discharge resistor is connected between the input terminals 2 and 3 when the switch is on, so even if the capacitor in the state where the charge is accumulated is the measurement target 100, the discharge unit 9 transfers this charge. It can be discharged, and the initial voltage value of the inter-terminal voltage V2 can be set to zero volt before the measurement process 50 is executed by the processing unit 10.

Next, the processing unit 10 executes the measurement process 50 shown in FIG. In the measurement process 50, the processing unit 10 first executes the first specific process to specify whether or not the connected measurement target 100 is a diode (step 51). Specifically, in this first specific process, the processing unit 10 first executes a control process for the switching unit 7 to connect the output terminal and the input terminal 3 of the AC voltage supply unit 4 (switching state (). It shifts to the switching state shown in FIG. Further, the processing unit 10 executes a control process for the AC voltage supply unit 4 to start the output of the AC voltage V1. As a result, the AC voltage V1 is supplied to the path leading to the internal ground G via the switching unit 7, the input terminal 3, the measurement target 100, and the input terminal 2 (that is, the AC voltage V1 is supplied to the measurement target 100). ). Further, the AC voltage supply unit 4 outputs the trigger signal St1 to the processing unit 10 in synchronization with, for example, the first rising zero cross point P1 of the AC voltage V1 after the output of the AC voltage V1 is started. It should be noted that the configuration is not limited to the first rising zero crossing point P1, and the trigger signal St1 may be output in synchronization with the second and subsequent rising zero crossing points P1. Further, the voltmeter 8 is obtained by sampling the inter-terminal voltage V2 generated between the input terminals 2 and 3 due to the supply (application) of the AC voltage V1 to the input terminal 3 by the AC voltage supply unit 4. The voltage data Dv indicating the instantaneous value of the inter-voltage V2 is generated and output to the processing unit 10.

When the processing unit 10 detects the input of the trigger signal St1 during the execution of the first specific process, the processing unit 10 starts measuring the elapsed time from the input time of the trigger signal St1 and also starts measuring the elapsed time being measured. It detects whether or not the first start time ts1 has been reached and whether or not the first end time te1 has been reached. Then, when the elapsed time being measured reaches the first start time ts1 (when the start of the first phase range arrives), the processing unit 10 acquires the voltage data Dv output from the voltmeter 8. At the same time, the integration of the acquired voltage data Dv is started. Further, the processing unit 10 stops the acquisition and integration of the voltage data Dv after the elapsed time being measured reaches the first final time te1 (after the end of the first phase range has arrived). That is, the processing unit 10 integrates the voltage data Dv acquired within the first phase range to calculate the integrated value (first integrated value). The average value of the voltage data Dv in the first phase range is calculated by dividing the integrated value by the number of voltage data Dv acquired in the first phase range. In this example, the integrated value is integrated in this way. The average value calculated from the value shall also be treated as a kind of "integrated value".

In the calculation of the first integrated value, the processing unit 10 first stores all the voltage data Dv acquired within the first phase range in the memory once, and then reads all the voltage data Dv from the memory to the first. It is possible to adopt a configuration in which one integrated value is calculated, but in this example, when the processing unit 10 sets the initial value of the integrated value to zero and acquires new voltage data Dv, it is immediately before being stored in the memory. To calculate a new integrated value by adding this acquired new voltage data Dv to the integrated value (one integrated value) of, and store this calculated new integrated value in the memory instead of the immediately preceding integrated value. Therefore, the configuration for calculating the first integrated value is adopted. Therefore, in this example, since it is not necessary to secure a storage area in the memory for storing all the voltage data Dv in the first phase range, it is possible to significantly reduce the memory capacity, which enables the capacity. It is possible to inexpensively manufacture the measuring device 1 by using an inexpensive memory with a small amount of data.

In this case, for example, the inter-terminal voltage V2 in one cycle T1 of the AC voltage V1 from the output timing of the trigger signal St1 is the same as the AC voltage V1 when the measurement target 100 is a resistor or a capacitor, as shown in FIG. It becomes a phase sinusoidal voltage. On the other hand, the terminal voltage V2 becomes the forward voltage of the diode in the first half cycle when the AC voltage V1 is applied in the forward direction when the measurement target 100 is a diode, and the AC voltage V1 is applied in the reverse direction in the latter half. In a half cycle, the sinusoidal voltage has the same phase as the AC voltage V1.

Therefore, when the measurement target 100 is a resistor or a capacitor, one zero cross point P2 of the AC voltage V1 (in this figure, the case where the measurement target 100 is a resistor is shown as an example) as shaded in FIG. Since the sign (±) is opposite and the absolute value is the same for the integrated value before and after this one zero cross point P2 with reference to the point with a phase of 180 degrees), these two integrated values The sum of the values, that is, the integrated value calculated by the processing unit 10, is theoretically zero (nearly zero when the measurement error is taken into consideration). On the other hand, when the measurement target 100 is a diode, as shown by the shaded area in FIG. 5, the integrated value before and after the one zero cross point P2 is the absolute value although the sign is opposite. Is not the same value (it is possible to surely make different values by defining the above value b as an appropriate value), so the sum of these two integrated values, that is, the processing unit 10 calculates. The integrated value to be calculated does not become zero.

Therefore, the processing unit 10 is based on whether or not the integrated value of the calculated voltage data Dv in the first phase range is zero (for example, a predetermined determination range (-Vth or more + Vth or less) defined around zero. When it is not zero (outside this judgment range), the measurement target 100 is specified as a diode, and when it is almost zero (included within this judgment range). When), the measurement target 100 is identified as not a diode (that is, a resistor or a capacitor). Further, the processing unit 10 executes a control process for the AC voltage supply unit 4 to stop the output of the AC voltage V1. As a result, the first specific process is completed.

When the processing unit 10 specifies that the measurement target 100 is not a diode in the first specific process, the processing unit 10 executes the second specific process so that the connected measurement target 100 is a resistor or a capacitor. (Step 52). Specifically, in this second specific process, the processing unit 10 first executes a control process for the switching unit 7 to enter a switching state in which the output terminal and the input terminal 3 of the AC current supply unit 5 are connected. Migrate. Further, the processing unit 10 executes a control process for the alternating current supply unit 5 to start the output of the alternating current I1. As a result, the alternating current I1 is supplied to the path leading to the internal ground G via the switching unit 7, the input terminal 3, the measurement target 100, and the input terminal 2 (that is, the alternating current I1 is supplied to the measurement target 100). ). Further, the AC current supply unit 5 outputs the trigger signal St2 to the processing unit 10 in synchronization with, for example, the first rising zero cross point P3 of the AC current I1 after the output of the AC current I1 is started. It should be noted that the configuration is not limited to the first rising zero crossing point P3, and the trigger signal St2 may be output in synchronization with the second and subsequent rising zero crossing points P3. Further, the voltmeter 8 is obtained by sampling the terminal voltage V2 generated between the input terminals 2 and 3 due to the supply (application) of the AC current I1 to the input terminal 3 by the AC current supply unit 5. The voltage data Dv indicating the instantaneous value of the intercurrent voltage V2 is generated and output to the processing unit 10.

When the processing unit 10 detects the input of the trigger signal St2 during the execution of the second specific processing, the processing unit 10 starts measuring the elapsed time from the input time of the trigger signal St2 and also starts measuring the elapsed time being measured. It detects whether or not the second start time ts2 has been reached and whether or not the second end time te2 has been reached. Then, when the elapsed time being measured reaches the second start time ts2 (when the start of the second phase range arrives), the processing unit 10 acquires the voltage data Dv output from the voltmeter 8. At the same time, the integration of the acquired voltage data Dv is started. Further, the processing unit 10 stops the acquisition and integration of the voltage data Dv after the elapsed time being measured reaches the second end time te2 (after the end of the second phase range has arrived). That is, the processing unit 10 integrates the voltage data Dv acquired within the second phase range to calculate the integrated value (second integrated value). The average value of the voltage data Dv in the second phase range is calculated by dividing the integrated value by the number of voltage data Dv acquired in the second phase range. In this example, the integrated value is integrated in this way. The average value calculated from the value shall also be treated as a kind of "integrated value".

Also in the calculation of the second integrated value, it is possible to adopt a configuration in which all the voltage data Dv acquired within the second phase range is temporarily stored in the memory and then the second integrated value is calculated. In this method, the processing unit 10 calculates the second integrated value by the same method as when calculating the first integrated value. Therefore, in this example, since it is not necessary to secure a storage area in the memory for storing all the voltage data Dv in the second phase range, it is possible to significantly reduce the memory capacity, which enables the capacity. It is possible to inexpensively manufacture the measuring device 1 by using an inexpensive memory with a small amount of data.

In this case, for example, the voltage V2 between terminals in one cycle T1 of the AC current I1 from the output timing of the trigger signal St2 has the same phase as the AC current I1 when the measurement target 100 is a resistor, as shown in FIG. It becomes a sinusoidal voltage. On the other hand, the terminal voltage V2 is a sinusoidal voltage whose phase is 90 degrees behind the alternating current I1 when the measurement target 100 is a capacitor.

Therefore, when the measurement target 100 is a resistor, as shown by the shaded area in FIG. 7, it is before the one zero cross point P4 (the point having a phase of 180 degrees) of the alternating current I1 as a reference. Since the sign (±) of the integrated value and the subsequent integrated value are opposite and the absolute value is the same, the sum of these two integrated values, that is, the integrated value calculated by the processing unit 10 is theoretically zero (measurement). When the error is taken into consideration, it becomes almost zero). On the other hand, when the measurement target 100 is a capacitor, the integrated value before the one zero cross point P4 and the integrated value after the above one zero cross point P4 have the same sign (+ in this example, as shaded in FIG. ), That is, the sum of these two integrated values, that is, the integrated value calculated by the processing unit 10 does not become zero.

Therefore, the processing unit 10 is based on whether or not the integrated value of the calculated voltage data Dv in the second phase range is zero (for example, a predetermined determination range (-Vth or more + Vth or less) defined around zero. If it is not zero (outside this judgment range), the measurement target 100 is specified as a capacitor, and if it is almost zero (included within this judgment range). When), the measurement target 100 is specified as a resistor. Further, the processing unit 10 executes a control process for the alternating current supply unit 5 to stop the output of the alternating current I1. As a result, the second specific process is completed.

When the processing unit 10 executes the first specific process and identifies that the measurement target 100 is a diode, the processing unit 10 executes a forward voltage measurement process as a measurement object measurement process (step 53), and performs the second specific process. When it is executed and the measurement target 100 is specified as a resistance, the resistance measurement process as the measurement target measurement process is executed (step 54), and the second specific process is executed to specify that the measurement target 100 is a capacitor. When this is done, the discharge process is executed (step 55) and the capacity measurement process as the measured amount measurement process is executed (step 56).

In this case, in the forward voltage measurement process, the processing unit 10 first executes a control process for the switching unit 7 to shift to a switching state in which the output terminal and the input terminal 3 of the DC current supply unit 6 are connected. .. Further, the processing unit 10 executes a control process for the direct current supply unit 6 to start the output of the direct current I2. As a result, the DC current I2 is supplied to the path leading to the internal ground G via the switching unit 7, the input terminal 3, the measurement target 100, and the input terminal 2 (that is, the DC current I2 is supplied from the input terminal 3 to the input terminal). It is supplied to the measurement target 100 so as to flow toward 2.) Further, the voltmeter 8 is obtained by sampling the voltage V2 between terminals generated between the input terminals 2 and 3 due to the supply (application) of the DC current I2 to the input terminal 3 by the DC current supply unit 6. The voltage data Dv indicating the instantaneous value of the inter-voltage V2 is generated and output to the processing unit 10. In this case, since the direct current I2 flows in the forward direction through the diode connected between the input terminals 2 and 3 as the measurement target 100, the terminal voltage V2 becomes the forward voltage of the diode.

Next, the processing unit 10 acquires one or a plurality of the voltage data Dv, measures the voltage value V2a of the inter-terminal voltage V2, and stores it as the voltage value Vf of the forward voltage. Further, the processing unit 10 executes a control process for the direct current supply unit 6 to stop the output of the direct current I2. This completes the forward voltage measurement process. When a plurality of voltage data Dvs are acquired, the processing unit 10 can calculate an average value of these and measure the voltage value V2a of the inter-terminal voltage V2 based on the average value.

Further, in the resistance measurement process, the processing unit 10 first measures and stores the voltage value V2a of the inter-terminal voltage V2 in the same manner as in the forward voltage measurement process described above. Next, the processing unit 10 calculates and stores the resistance value R of the resistor, which is the measurement target 100, by dividing the measured voltage value V2a of the terminal voltage V2 by the known current value I2a of the direct current I2. Further, the processing unit 10 executes a control process for the direct current supply unit 6 to stop the output of the direct current I2. This completes the resistance measurement process.

Further, in the discharge process, the processing unit 10 executes control over the discharge unit 9, shifts the switch of the discharge section 9 from the off state as the initial state to the on state once, and then shifts the switch to the off state again. As a result, since the discharge resistor is connected between the input terminals 2 and 3 when the switch is on, even if the electric charge is accumulated in the capacitor as the measurement target 100 in the first specific process and the second specific process. , This charge is discharged by the discharge unit 9. Therefore, before executing the capacitance measurement process (step 56), the voltage value of the terminal voltage V2 (that is, the voltage across the capacitor) can be set to zero volt.

In the capacitance measurement process after the discharge process, the processing unit 10 first executes a control process for the DC current supply unit 6 in the same manner as in the forward voltage measurement process described above, and the DC is a step signal. The output of the current I2 is started. Further, the processing unit 10 starts measuring the elapsed time from the time when the output of the DC current I2 is started to the DC current supply unit 6, and the measured elapsed time is a predetermined time tk. Is detected.

Next, when the processing unit 10 detects that the elapsed time being measured has reached this time tch, the processing unit 10 acquires the voltage data Dv output from the voltmeter 8 at this detection time, and at the time of this detection, The voltage value V2a of the voltage between terminals V2 is calculated.

In this case, when a capacitor having an initial charge of zero is charged with a DC constant current, the voltage between both ends of the capacitor (charging voltage) increases in proportion to the charging time with zero volt as the initial value. That is, the relational expression of C × V2a = I2a × tch holds between the capacitance value C, the voltage value V2a, the current value I2a, and the time chic (charging time in this example). Subsequently, the processing unit 10 calculates and stores the capacitance value C (= I2a × tch / V2a) of the capacitor, which is the measurement target 100, based on this relational expression. Further, the processing unit 10 executes a control process for the direct current supply unit 6 to stop the output of the direct current I2. As a result, the capacity measurement process is completed.

The processing unit 10 performs an output process (step 57) when the forward voltage measurement process (step 53) is completed, when the resistance measurement process (step 54) is completed, and when the capacitance measurement process (step 56) is completed. The measurement result measured in the measurement process executed immediately before is executed (voltage value Vf of forward voltage in forward voltage measurement process, resistance value R in resistance measurement process, capacitance value C in capacitance measurement process). Output to the output unit 11. In this example, since the output unit 11 is composed of a display device, the measurement result is displayed on the screen. As a result, the measurement process 50 is completed.

As described above, in the measuring device 1, when the processing unit 10 executes the measuring process 50 to specify whether the measurement target 100 is a diode, a resistor, or a capacitor, and also identifies the diode. The forward voltage measurement process is executed as the measured amount measurement process to measure the voltage value Vf of the forward voltage as the measured amount, and when it is specified as a resistance, the resistance measurement process is executed as the measured amount measurement process. The resistance value R as the measured amount is measured, and when it is specified as a capacitor, the capacitance measurement process is executed as the measured amount measuring process to measure the capacitance value C as the measured amount.

Therefore, according to the measuring device 1, the measurement function matching the measured quantity of the measurement target 100 is automatically and surely selected (that is, the measurement process matching the measured quantity is automatically and surely executed). Therefore, as a result of avoiding human error, the measured amount of the measurement target 100 can be reliably measured.

Further, the measuring device 1 includes a discharge unit 9 arranged between the input terminals 2 and 3, and when the processing unit 10 specifies that the measurement target 100 is a capacitor in the second specific process, the measured amount is measured. Prior to the execution of the capacity measurement process (step 56) as the process, the discharge process (step 55) of operating the discharge unit 9 to discharge the electric charge accumulated in the capacitor is executed. Therefore, according to this measuring device 1, even if the electric charge remains in the capacitor after the execution of the second specific processing, the capacitance measuring processing can be executed after the electric charge is discharged, so that the capacitance value of the capacitor can be executed. C can be measured accurately.

As shown in FIG. 2, an example in which the first specific process is first executed in the measurement process 50 and then the second specific process is executed is described above, but in the measurement device 1, the first is the first. It is also possible to adopt a configuration in which the second specific process is executed and then the first specific process is executed.

Further, the processing unit 10 executes the specific process (first specific process and the second specific process), and when it is specified as a diode, executes the measured amount measurement process (forward voltage measurement process) as the measured amount. When the forward voltage is measured and it is specified as a resistance, the measured amount measurement process (resistance measurement process) is executed to measure the resistance value as the measured amount, and when it is specified as a capacitor, the measured amount measurement process (measurement amount measurement process). Although the measuring device 1 has adopted the preferable configuration of executing the capacitance measuring process) to measure the capacitance value as the measured amount, the present invention is not limited to this configuration. For example, when the processing unit 10 executes a specific process (first specific process and second specific process) to specify a measurement target, the specific result (whether the measurement target is a diode, a resistor, or a capacitor) is specified. ) Is output (displayed) to the output unit 11, and then an instruction (for example, an operation operated by the user) from the user of the measuring device 1 who has confirmed the specific result output (displayed) to the output unit 11 Waiting for the instruction output from the unit), if the content of the instruction is a forward voltage measurement process, this measurement process, or if the content of the instruction is a resistance measurement process It is also possible to adopt a configuration in which this measurement process or, in the case of capacity measurement process, this measurement process) is executed.

Further, in the above example, the processing unit 10 uses the alternating current (alternating current) I1 in the second specific processing (step 52) to determine whether the connected measurement target 100 is a resistor or a capacitor. Although a specific configuration is adopted, the configuration for specifying whether the measurement target 100 is a resistor or a capacitor is not limited to this. For example, in this second specific processing, the processing unit 10 causes the DC current supply unit 6 to output the above-mentioned DC current (DC constant current) I2, and at this time, the terminal voltage V2 is transmitted via the voltmeter 8. A configuration is adopted in which the measurement target 100 is a resistor or a capacitor based on whether or not the measured terminal voltage V2 rises with almost no delay from the rise of the direct current I2. You can also do it. In this configuration, the processing unit 10 identifies that the measurement target 100 is a resistor when the inter-terminal voltage V2 rises with almost no delay from the rise of the DC current I2, and when it rises with a delay (when it gradually rises). Identify it as a capacitor. By adopting this configuration, the AC current supply unit 5 can be omitted, and the configuration of the measuring device can be simplified.

1 Measuring device 2, 3 Input terminal 4 AC voltage supply unit 5 AC current supply unit 6 DC current supply unit 8 Voltmeter (voltage detection unit)
9 Discharge unit 10 Processing unit 100 Measurement target C Capacitor capacity value Dv Voltage data I2 DC current R Resistance resistance value V2 Terminal voltage V2a Voltage value Vf Forward voltage voltage value

Claims (2)

A pair of input terminals, a voltage detection unit that outputs voltage data indicating a voltage between the pair of input terminals, a current supply unit that can supply a constant current between the pair of input terminals, and the constant current The voltage value of the voltage between the terminals is measured based on the voltage data output from the voltage detection unit in the supply state, and the measured voltage is measured when the measurement target connected between the pair of input terminals is a diode. Based on the value, the forward voltage of the diode is measured as the amount to be measured, and when the measurement target connected between the pair of input terminals is a resistor or capacitor, the measured voltage value and the constant current current value are used. the capacitance value of the resistance or the capacitor of the resistor and a processing unit for executing the measurement quantity measurement process of measuring a quantity to be measured based on,
Wherein the processing unit is a measurement apparatus that performs a specific process in which the measurement object that is connected between the pair of input terminals to identify whether a capacitor whether a diode resistor, said pair of input Equipped with an AC voltage supply unit that can supply a constant AC voltage between the terminals
The processing unit is a voltage included in a predetermined first phase range centered on one zero cross point of the AC constant voltage in the voltage data output from the voltage detection unit in the state of supplying the AC constant voltage. A measuring device that calculates an integrated value for data and executes a first specific process as the specific process for specifying whether or not the measurement target is a diode based on whether or not the integrated value is almost zero. .. An AC current supply unit capable of supplying an AC constant current between the pair of input terminals is provided.
When the processing unit specifies that the measurement target is not a diode, the processing unit centers on one zero cross point of the AC constant current in the voltage data output from the voltage detection unit in the AC constant current supply state. The integrated value for the voltage data included in the predetermined second phase range is calculated, and whether the measurement target is a diode or a capacitor is specified based on whether or not the integrated value is substantially zero. measuring apparatus according to claim 1, wherein performing a second identification processing as the specific process.

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