JPH03199980A - Apparatus for inspecting wiring of connecting cable - Google Patents

Abstract

PURPOSE:To make it possible to detect defective connections and defective wirings such as partial wire breakages even in the case of a weak current by judging the pass or fail of the state of the wiring based on the potential difference when the current in the respective maximum allowance value is made to flow through each wiring path. CONSTITUTION:Connectors 4 and 5 are connected to connectors CN1 and CN2 of connecting cables 1 to be inspected. The current value for a constant current supply 2 is set with a current-value setting device 3 at the maximum allowable current value of each of conductors CAa-CAd corresponding to the maximum allowable current value of each wiring path. A reference voltage value is set with a reference-voltage generator 7 at the potential difference between the connectors 4 and 5 when the maxi mum current at the maximum allowable value flows through each of the conductors CAa-CAd. Switches SW1, SW5 and SW9 are turned ON with a switching device 10. The wiring paths including the conductor CAa are electrified, and the potential differ ence between the connectors 4 and 5 is compared with the reference voltage 7 in a comparator 6. Then the device 10 is operated, and each wiring path of the cables 1 is sequentially electrified. The outputs of the comparator at these times are stored 8a-8d. The presence or absence of the defect in the wiring state of the path is judged with a judging output circuit 9 based on the stored contents.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a device for inspecting the wiring condition of a connecting cable used to connect devices when transmitting signals between control devices, for example.

Conventional technology There is a wiring inspection device that inspects connection cables (a cable or harness with connectors connected at both ends is called a connection cable) for wiring defects such as short circuits, disconnections, and incorrect wiring.

This wiring inspection device passes a predetermined weak current between each connector pin of both connectors of the connection cable to be inspected.
It determines whether the potential difference matches a reference voltage or not, and notifies the operator of the determination result by sounding a buzzer or the like.

Problems to be Solved by the Invention In the above-mentioned conventional example, the soldering and crimping work for connecting each connector pin to each conductor of the cable is not appropriate, and the connection part is only in contact with each other. In the case of a defect or a partial disconnection where several conductor strands are disconnected,
Since the current that is passed for testing is a weak current, the current flows in the same way as in a normal case, and no change appears in the potential difference.

Therefore, there is a problem in that wiring defects such as connection defects and partial disconnections cannot be detected.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a wiring inspection device that can reliably detect wiring defects in connection cables.

Means for Solving the Problems A connection cable wiring inspection device according to the present invention includes a constant current source for sequentially and selectively passing current through each wiring route of a connection cable to be inspected, and an output of this constant current source. A current value setting device for variably setting the current value to the maximum allowable current value unique to each wiring route; The present invention is characterized by comprising a determining means for determining whether the wiring state of the connecting cable is good or bad based on each potential difference.

The working current value setting device sets the output current value of the constant current source to the maximum allowable current value unique to each wiring route of the connection cable to be inspected, and sets the output current of the constant current source for each wiring route individually. The voltage difference generated at both ends of each wiring path is detected. Then, for example, each potential difference is compared with each potential difference that should occur under normal conditions, and if the difference is within a predetermined range, it is determined that the wiring condition is good, and if it is outside the predetermined range, the wiring condition is determined to be poor. It is determined that

Example Hereinafter, one embodiment of the present invention will be described based on the drawings.

In the figure, ■ indicates the connection cable to be inspected.

The connection cable l consists of a cable main body CA including four conductors CAa to CA, d, a connector CNI to which each connector bin is connected to one end of each conductor CAa to CAd, and a connector CNI to which each connector bin is connected to the other end of each conductor CAa to CAd. It consists of a connector CN2 to which each connector pin is connected. 2 is a constant current source, 3 is a current value setter for variably setting the output current value of the constant current source 2 to a predetermined current value, and 4 and 5 are the respective connectors CN1. CN2
The connectors SWI to SW4 are respectively connected to connector CN1. By connecting CN2 to the connectors 4.5, each conductor CAa=
Each switch group connected in series with CAd is shown. Also, SW5 to SW8 are connectors CNI and CN2.
are connected to the connectors 4.5, respectively, so that each conductor CAa=CAd is connected in parallel to the constant current source 2, and 6 is a switch group between the connectors 4 and 5, which is provided via the switch groups SW5 to SW8. The comparator 6 compares the potential difference between the potential difference and the voltage given from the reference voltage generator 7 and turns on the output if the difference is within a predetermined value. A register 9 is connected to the output terminal of the comparator 6 and temporarily stores the output state of the comparator 6.A register 9 judges whether the wiring state of the connecting cable 1 is good or bad based on the contents stored in each register 8a to 8d, and outputs the judgment result. The judgment output circuits that output are shown. Then, ■0 includes switches SWI, SW5, and SW9 in one group, and switches SW2. 1 group of SW6.5WIO, switch SW3. SW7. 1 group of SWI I,
Assuming switches 5W4SW8 and 5W12 as one group,
This is a switch changeover device that turns on/off the switches in each group simultaneously.

In this embodiment, the wiring condition of the connection cable 1 is inspected by the following operating procedure.

First, with all switches SWI to 5W12 turned off, each connector C, N1... of the connection cable 1 to be inspected. C.N.
Connect connectors 4 and 5 to 2, respectively. Next, by operating the current setting device 3, the output current value of the constant current source 2 is set to the maximum allowable current value of each conductor CAa=CAd, which corresponds to the maximum allowable current value of each wiring route of the connecting cable l, and The current of the maximum allowable current value is
The voltage generated by the reference voltage generator 7 is set to the potential difference between the connectors 4 and 5 that occurs when the voltage normally flows through the terminal d. This setting operation only needs to be performed once before the next energization operation if the maximum allowable current values of each wiring route are the same, but if they are different, it is necessary to perform this setting operation for each energization operation. Then, by operating the switch changeover device 10, switches SWI, SW5 . S
Turn on W9 and energize the wiring path including the conductor CAa. By this operation, the potential difference generated between the connectors 4 and 5 is compared with the voltage generated by the reference voltage generator 7 by the comparator 6,
The output state of comparator 6 is stored in register 8a.

Thereafter, by operating the switch changeover device IO, switches SWI, SW5 . Turn off SW9, switch SW2. SW
6,5WIO is turned on, then switch SW2. SW6. S
Turn off WIO, turn on switches SW3 and SW7.5WII, and turn on switch SW3. SW7. SWI I is turned off, switches 5W4SW8 and 5WI2 are turned on, and each wiring route of the connection cable 1 is sequentially energized.

Through the above operations, each output state of the comparator 6 when energized to each wiring route of the connection cable I is set to each register 81 to 8.
d respectively. Then, the determination output circuit 9 reads out the contents stored in each of the registers 8a to 8d, determines based on the contents whether or not there is a wiring route in which the wiring condition is defective, and outputs the determination result. If there is a defective wiring route, the determination output will be used, for example, by FD, etc.
Which wiring route is defective is identified and displayed.

As described above, in this embodiment, the acceptability of each wiring route is determined by passing the maximum permissible flow value of the conductor CA a = CA d through each wiring route of the connection cable 1.
In addition to detecting wiring defects such as short circuits, disconnections, and incorrect wiring,
In cases where the soldering is poor and the connector pins of connectors CN1 and CN2 are simply touching each conductor CA a - CAd, there is a connection failure, or there is a partial disconnection where some of the wires of conductor CAa = CAd are disconnected. Even in this case, the larger the current value, the greater the voltage drop due to the increased resistance value caused by the wiring defect, making it possible to detect the wiring defect.

Effects of the Invention As described above, according to the present invention, a current of the maximum permissible current value is passed through each wiring path of the connection cable to be detected, and the quality of the wiring condition of the connection cable is determined. It is now possible to reliably detect wiring defects such as poor connections and partial wire breaks that would not be detected by simply passing the signal.

[Brief explanation of drawings]

The figure is a circuit diagram showing the configuration of an embodiment of the present invention. 1... Connection cable, 2... Constant current source, 3... Current value setter, 6... Comparator, 7. Reference voltage generator, 8a to 8d... Register, 9... Judgment Output circuit.

Claims (1)

[Claims] (1) A constant current source for sequentially and selectively passing current through each wiring route of the connection cable to be inspected, and variable output current value of this constant current source to the maximum allowable current value unique to each wiring route. a current value setter for setting, and determining whether the wiring condition of the connection cable is good or bad based on each potential difference that occurs when a current having a unique maximum allowable current value is individually passed through each of the wiring paths. A wiring inspection device characterized by comprising: a determining means.