JP4141545B2 - Insulation meter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an insulation meter for measuring an insulation resistance value of an electronic device, an electronic component or an insulating material.
[0002]
[Prior art]
Conventionally, an insulation meter has been used to measure an insulation resistance value of an electronic device, an electronic component, or an insulating material. The insulation meter is a high resistance measuring device generally configured as shown in FIG. is there.
[0003]
That is, the insulation meter 1 </ b> A includes a measurement voltage source 10 and a high sensitivity ammeter 20 connected in series to the measurement voltage source 10. The insulation meter 1A is provided with a plus (+) side measurement terminal 2 connected to the plus (+) side of the measurement voltage source 10 and a minus (−) side measurement terminal 3 connected to the high sensitivity ammeter 20. ing. A plus (+) side plug 103 and a minus (−) side plug 104 of the measurement cables 101 and 102 are inserted into the plus (+) side measurement terminal 2 and the minus (−) side measurement terminal 3, respectively. The other end of 102 is connected to a sample 200 such as an electric device. In this state, a predetermined voltage is applied from the measurement voltage source 10 to the sample 200, the current flowing through the sample 200 is measured by the high sensitivity ammeter 20, and the resistance of the sample 200 is measured.
[0004]
[Problems to be solved by the invention]
In the conventional insulation meter 1A having the above configuration, the plugs 103 and 104 of the measurement cables 101 and 102 are inserted into the plus (+) side measurement terminal 2 and the minus (−) side measurement terminal 3 of the insulation meter 1A. If the measurement cables 101 and 102 are inadvertently pulled, the plugs 103 and 104 of the measurement cables 101 and 102 may come off from the measurement terminals 2 and 3 of the insulation meter 1A.
[0005]
The insulation meter outputs a high measurement voltage, and the measurement operator turns the measurement voltage on and off with the operation switch. If the measurement cable is disconnected during the measurement, there is a possibility of causing an unexpected risk to the measurement person. is there. Therefore, it is necessary for the measurer to always pay attention so that the plug of the measurement cable being measured does not come out of the measurement terminal of the insulation meter, and the measurement person cannot concentrate on the measurement work, and there is a problem in workability.
[0006]
Accordingly, an object of the present invention is to provide an insulation meter that can ensure the safety of the measurer without causing any danger to the measurer even if the measurement cable is disconnected during the measurement.
[0007]
Another object of the present invention is to provide an insulation meter that allows a measurer to concentrate on measurement without having to worry about disconnection of a measurement cable during measurement, and to improve workability. .
[0008]
[Means for Solving the Problems]
The above object is achieved by an insulation meter according to the present invention. In summary, the present invention comprises a positive and negative measurement terminals connected to a measurement voltage source, a measurement cable plug is inserted into the measurement terminal, and the other end of the measurement cable is connected to the sample, thereby measuring voltage. In an insulation meter that measures the resistance of a sample by applying a voltage from a source to the sample and measuring the current flowing through the sample.
Plug disconnection detecting means for detecting that the plug of the measurement cable inserted into the measurement terminal on the plus side and the minus side has come out of the measurement terminal;
A switch circuit is installed between the voltage circuit of the measurement voltage source and the measurement terminal,
When the plug disconnection detecting means detects that the plug of the measurement cable has been disconnected from the measurement terminal, the output from the voltage circuit of the measurement voltage source is set to zero via the high voltage controller of the measurement voltage source. At the same time, the output control switch of the switch circuit is also turned off through the high-voltage control unit .
[0009]
According to one embodiment of the present invention, the plug omission detection means,
(A) connected to a high voltage control unit of the measurement voltage source via a control device, a signal from the plug disconnection detection means is transmitted to the control device, and the control device controls the high voltage control unit; Turn off the output control switch of the switch circuit by the high voltage control unit and set the output of the high voltage power supply of the voltage circuit to zero, or
(B) It is directly connected to the high voltage control unit of the measurement voltage source without going through the control device, and a signal from the plug disconnection detecting means is transmitted to the high voltage control unit, and the high voltage control unit The output control switch is turned OFF, and the output of the high voltage power supply of the voltage circuit is set to zero.
[0010]
According to another embodiment of the present invention, the measurement terminal includes a socket portion that receives a shaft portion of a plug of a measurement cable, and a connection hole portion that is electrically connected to a tip connector of the plug. The plug disconnection detecting means is provided in the section. Preferably, the plug disconnection detecting means is a switch having an operating piece, and the operating piece protrudes into the socket portion. When the plug is inserted into the socket portion, the plug shaft When the switch is pressed to turn on the switch and the plug is pulled out from the socket, the pressure applied by the plug shaft is released and the switch is turned off.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the insulation meter according to the present invention will be described in more detail with reference to the drawings.
[0012]
Example 1
FIG. 1 shows the overall configuration of an insulation meter according to the present invention. According to the present embodiment, the insulation meter 1 includes a measurement voltage source 10 and a measurement unit 20 that is a high-sensitive ammeter connected in series to the measurement voltage source 10 as in the prior art. The insulation meter 1 has a plus (+) side measuring terminal 2 connected to the plus (+) side of the measurement voltage source 10 and a minus (−) side measuring terminal 3 connected to the high sensitivity ammeter 20. The plus (+) side measuring terminal 2 and the minus (−) side measuring terminal 3 are inserted with the plus (+) side plug 103 and the minus (−) side plug 104 of the measurement cables 101 and 102, respectively. The other ends of the measurement cables 101 and 102 are connected to a sample 200 such as an electric device.
[0013]
FIG. 3 shows a schematic configuration of an electric circuit according to an embodiment of the insulation meter 1. The measurement voltage source 10 includes a voltage circuit 11 having a power source such as a high voltage power source, a switch circuit 12 having a control switch, and a high voltage control unit 13. The minus (−) side of the voltage circuit 11 is connected to the measuring unit 20 via the switch circuit 12, and the plus (+) side of the voltage circuit 11 is connected to the plus side changeover switch 5. The measurement unit 20, which is a high sensitivity ammeter, includes a current-voltage converter 21 connected to the minus side changeover switch 6, and the current-voltage converter 21 includes a DC amplifier 22 and an A / D converter 23. Is connected to a control device (CPU) 30 via The control device 30 is provided with a liquid crystal display device 31, an RS232C device 32, a key substrate 33, and the like. The insulation meter 1 according to the present embodiment includes a discharge unit 40 including a discharge unit 41 and a discharge control unit 42, and is controlled by the control device 30.
[0014]
According to the present embodiment, the plus side changeover switch 5 and the minus side changeover switch 6 are charge / discharge switches that can be switched in three steps of measurement, charge, and discharge in conjunction with each other. Therefore, for example, when measuring a capacitive sample such as a capacitor, voltage is applied to the sample by `` charging '', pre-charging for measurement, then switching to `` measuring '' and performing measurement. By switching to “discharge”, the charge charged in the sample can be discharged.
[0015]
According to the present embodiment, the plus side measuring terminal 2 and the minus side measuring terminal 3 installed in the insulation meter 1 that cooperates with the charge / discharge switches 5 and 6 are connected to the measuring cable 101, as shown in FIG. Socket portions 2A and 3A for receiving the shaft portions 103A and 104A of the positive side plug 103 and the negative side plug 104, and connection hole portions 2B and 3B electrically connected to the tip connectors 103B and 104B of the plugs. I have.
[0016]
Further, according to the present invention, the plug removal detecting means 4 for detecting plug insertion / removal is provided in the socket portions 2A, 3A. The plug disconnection detecting means 4 is, for example, a switch provided with an operating piece 4A. The operating piece 4A protrudes into the socket portions 2A and 3A, and the plugs 103 and 104 are inserted into the socket portions 2A and 3A. When the plugs 103 and 104 are pressed by the shaft parts 103A and 104A, the switch 4 is turned on, and the plugs 103 and 104 are extracted from the socket parts, the pressing force from the plug shaft parts 103A and 104A is released. Then, the switch 4 is turned off. In this embodiment, the two switches 4 arranged in the sockets 2A and 3A are connected in series as shown in the figure, and it is determined that the plug disconnection detecting means 4 is OFF regardless of which plug is disconnected. To do.
[0017]
Further, in the present invention, as understood with reference to FIG. 4, the plug disconnection detecting means 4 is connected to the high voltage control unit 13 via the control device 30, and the high voltage control unit 13 detects the plug disconnection detection. The output control switch of the switch circuit 12 and the high voltage power supply of the voltage circuit 11 are controlled according to the signal from the means 4. That is, when one or both plugs are removed from the socket, either or both switches are turned OFF, thereby turning the output control switch OFF and outputting from the high voltage power supply. 0V.
[0018]
The operation of the insulation meter according to the present invention having the above configuration will be described with reference to the flowchart shown in FIG.
[0019]
The measurement cables 101 and 102 are connected to the sample 200 and measurement is started (step 1). Whether or not the measurement cables 101 and 102 are securely connected to both measurement terminals 2 and 3 is confirmed by the detection switch 4 (step 2). When the measurement cables 101 and 102 are not securely connected by the detection switch 4, the output control switch of the switch circuit 12 is turned off via the high voltage control unit 13 and the output from the high voltage power source of the voltage circuit 11 is set. Is set to 0V (step 6), and the process ends (step 7).
[0020]
If the connection of the measurement cables 101 and 102 is securely performed by the detection switch 4, the process proceeds to measurement work (step 3). If the measurement cables 101 and 102 are disconnected during the measurement operation, the detection switch 4 immediately detects this (step 4), turns off the output control switch of the switch circuit 12 via the high voltage control unit 13, and the voltage The output from the high voltage power supply of the circuit 11 is set to 0 V (step 6), and the process is terminated (step 7).
[0021]
The above steps 3 to 5 are repeated, and when the measurement operation is completed without the measurement cables 101 and 102 being disconnected during the measurement operation, the output control switch of the switch circuit 12 is turned off via the high voltage control unit 13, and the voltage circuit 11 The output from the high voltage power supply is set to 0 V (step 6), and the process is terminated (step 7).
[0022]
Example 2
FIG. 5 shows another embodiment of the present invention. In the first embodiment, the signal from the plug disconnection detecting means 4 is transmitted to the control device 30, the control device 30 controls the high voltage control unit 13, the output control switch of the switch circuit 12 is turned OFF, and the voltage circuit The output from 11 high voltage power supplies was set to 0V. In the present embodiment, considering the case where the control device 30 becomes uncontrollable due to some factor, the plug disconnection detecting means 4 is directly connected to the high voltage control unit 13 without the control device 30 being interposed. Other configurations are the same as those in the first embodiment.
[0023]
Therefore, according to the present embodiment, the high voltage control unit 13 controls the output control switch of the switch circuit 12 in accordance with the signal from the plug omission detection means 4. That is, when one or both of the plugs are removed from the socket portion, either or both of the switches are turned OFF, and thereby, for example, the base voltage of the transistor 14 provided in the switch circuit 12 Is turned OFF, and the output control switch 15 is turned OFF.
[0024]
【The invention's effect】
As described above, the insulation meter according to the present invention includes the positive and negative measurement terminals connected to the measurement voltage source, the measurement cable plug is inserted into the measurement terminal, and the other end of the measurement cable is connected to the sample. In the insulation meter that measures the resistance of the sample by applying a voltage from the measurement voltage source to the sample and measuring the current flowing through the sample, the plug of the measurement cable inserted into the positive and negative measurement terminals is It has plug disconnection detecting means for detecting that it has come out of the measurement terminal, a switch circuit is installed between the voltage circuit of the measurement voltage source and the measurement terminal, and the plug of the measurement cable is connected by the plug disconnection detection means. when it is detected that the exit from the measurement terminal, the output from the voltage circuit with a zero measurement voltage source through a high voltage control unit of the measurement voltage source, a high voltage controller Since it is configured to OFF even output control switches of the switch circuit and,
(1) Even if the measurement cable is disconnected during measurement, there is no danger to the measurer, and the measurer's safety can be ensured.
(2) It is not necessary for the measurer to worry about disconnection of the measurement cable during the measurement, and the operator can concentrate on the measurement and can improve workability.
Such effects can be achieved.
[Brief description of the drawings]
FIG. 1 is a diagram showing an overall configuration of an insulation meter according to the present invention.
FIG. 2 is a cross-sectional view showing an embodiment of a plug omission detecting means.
FIG. 3 is a diagram showing a schematic configuration of an electric circuit of an insulation meter according to the present invention.
FIG. 4 is a diagram showing a schematic configuration of a high voltage control unit of an insulation meter according to the present invention.
FIG. 5 is a diagram showing a schematic configuration of another embodiment of the high voltage controller of the insulation meter according to the present invention.
FIG. 6 is a flowchart for explaining the operation of the insulation meter according to the present invention.
FIG. 7 is a diagram showing an overall configuration of a conventional insulation meter.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Insulation meter 2, 3 Measurement terminal 4 Plug omission detection means 5, 6 Changeover switch 10 Measurement voltage source 11 Voltage circuit 12 Switch circuit 13 High voltage control unit 20 Measurement unit 30 Control device 101, 102 Measurement cable 103, 104 Plug 200 Sample

Claims (4)

It has positive and negative measurement terminals connected to the measurement voltage source, plug the measurement cable into the measurement terminal, connect the other end of the measurement cable to the sample, and apply voltage from the measurement voltage source to the sample. In an insulation meter that measures the resistance of a sample by measuring the current flowing through the sample,
Plug disconnection detecting means for detecting that the plug of the measurement cable inserted into the measurement terminal on the plus side and the minus side has come out of the measurement terminal;
A switch circuit is installed between the voltage circuit of the measurement voltage source and the measurement terminal,
When the plug disconnection detecting means detects that the plug of the measurement cable has been disconnected from the measurement terminal, the output from the voltage circuit of the measurement voltage source is set to zero via the high voltage controller of the measurement voltage source. In addition, the output meter switch of the switch circuit is also turned off through the high voltage controller . The plug disconnection detecting means is
(A) connected to a high voltage control unit of the measurement voltage source via a control device, a signal from the plug disconnection detection means is transmitted to the control device, and the control device controls the high voltage control unit; Turn off the output control switch of the switch circuit by the high voltage control unit and set the output of the high voltage power supply of the voltage circuit to zero, or
(B) It is directly connected to the high voltage control unit of the measurement voltage source without going through the control device, and a signal from the plug disconnection detecting means is transmitted to the high voltage control unit, and the high voltage control unit Turn off the output control switch and set the output of the high voltage power supply of the voltage circuit to zero.
Insulation meter claim 1, characterized in that. The measurement terminal includes a socket portion that receives a shaft portion of a plug of a measurement cable, and a connection hole portion that is electrically connected to a tip connector of the plug, and the plug drop detection means is provided in the socket portion. The insulation meter according to claim 1 or 2 . The plug disconnection detecting means is a switch provided with an operating piece, and the operating piece protrudes into the socket portion. When the plug is inserted into the socket portion, it is pressed by the shaft portion of the plug. 4. The insulation meter according to claim 3 , wherein when the switch is turned on and the plug is pulled out from the socket portion, the pressing by the shaft portion of the plug is released and the switch is turned off.

Images