JPH0349391B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a continuity testing device for wire harnesses used, for example, in automobiles and electrical equipment.

(Prior Art) Connection line circuits that connect various devices, for example, connections between devices such as headlights, tail lights, and other electronic devices installed in automobiles and power supplies, or connections between devices, As shown in Figure 1, a so-called wire harness 1 is made that is wired in accordance with the installation positions of various devices, and after fixing this to a predetermined position on the vehicle body 2 that is sent in the assembly line, the input and output ends are connected. Connection is performed using a connector 3 or the like. By the way, in the wire harness, in order to ensure operational reliability, it is important that each connection line 4 is properly connected to the connector used for connection with the above-mentioned equipment, etc., without error.

However, the number of connection lines 4 tends to become larger and larger due to the increasing functionality of automobiles and the like. For this reason, for example, as shown in FIG _.
Although the normal connection state is that a single line is connected by 4 ₃ and there is an empty line between 2 and 2, there is an empty line between 3 and 3 as shown in Figure 2 b. Even if it is rare, such misconnection cannot be avoided.

Therefore, in order to automatically, quickly and reliably detect connection errors and make repairs, a continuity test device, so-called wire harness checker, as shown in FIG. 3 is generally used. This device has a connector group 5, that is, a test relay wire 6 placed on a test stand 6, with the input end of the wire harness 1 connected to the connector 3 provided on the test stand 6 being a contact, and the output end being a contact. A connector group 5 consisting of connectors 5 ₁ , 5 _{2 .} 1], then press the single line connection key 9 to specify the address and set the connection status to "1". For example, press [2] on the keyboard 8 and then press the blank line key 10 to specify the address. Then, a switching command is sent to the write/read memory circuit 11 (RAM) in which the normal connection state shown in FIG. An operation management program that performs program step-up for comparison with the output of the switching circuit group 15 is provided with a read-only memory circuit 12 that is set by the addressing keyboard 8. Then, the operation is started by pressing the start key 13, and when an abnormality occurs through verification, the operation is temporarily stopped, and the return key 14 is pressed.
When pressed, the microcomputer 7 restarts operation from the beginning, the check switching circuit group 15, for example, as shown in FIG. 4, a switching transistor connects the side contact of the connector group 5 to the negative polarity of the power source E. T _r1 and a level detector L which connects the side contact to the positive polarity side of the power supply E via the switching transistor T _r2 and at the same time detects the potential appearing at the side contact as a "1" or "0" signal. It is provided with check switching circuits 15 ₁ , 15 ₂ . . . 15 _o . Then, the switching transistor T _r1 T _r2 switches from 1 to 1, 2 according to the switching signal from the microcomputer 7.
~2 contacts are turned on sequentially in order to allow current to flow through each connection line, thereby causing the second
As shown in Figure b, when there is a single wire connection between contacts 1 and 1, "1" is output from the level detector L, and 2-
“0” for empty lines like 2, 3-3
The check switching circuit group 15 and the display circuit 16, for example, step by step in synchronization with the switching of the check switching circuit group 15 in response to a command from the microcomputer 7, and display the contact number in sequence, for example. 3~ as shown in Figure 2 a
Although the single-wire connection between 3 and 3 is a normal connection state, when the wire is blank as shown in FIG. 2b and the output of the check switching circuit ₁₅₃ is "0", The display circuit 16 is formed of a display circuit 16 which stops the forwarding by stopping the transmission of commands from the microcomputer 7 that stops due to the checking operation, displays the contact number where the abnormality has occurred, and at the same time generates an abnormal sound. As shown in the flowchart shown in the figure, continuity of the wire harness is checked by performing a series of determination operations.

Continuity test equipment is also used that uses a hardware circuit to check the settings of the memory circuit for setting the normal connection mode and the output of the check switching circuit instead of using a program (software) as described above. .

(Problems with the Prior Art) However, regardless of whether the collation process is performed by software or hardware, the check switching circuit of the conventional device has problems with the check as described above with reference to FIG. Current can only flow in one direction through the test connection circuit. Therefore, for example, as shown in _FIG .
For example, if the diode _D1 is connected in the forward direction with respect to the current flow direction, continuity can be checked, but if the diode _D2 connected to the connection line ₄₅ is in the opposite direction, then , current cannot flow. Therefore, conventional testers cannot perform continuity checks on wire harnesses containing diodes.

The present invention provides a continuity test device that can perform a continuity check even in the above-mentioned cases, and is intended to expand the checking function.

[Structure of the invention]

(Construction and Action for Solving the Problems) The present invention is characterized in that the check switching circuit is configured to allow current to flow in both forward and reverse directions through the connection line circuit under test by switching the changeover switch. The above-mentioned switch circuit is switched in accordance with the connection polarity of the diode by a signal sent by a command word set in the memory circuit for setting the operation management program, and an element having a current flow blocking effect is connected. It is also possible to check.

(Embodiment) FIG. 6 is a circuit diagram of a main part showing an embodiment of the present invention, in which 4 ₃ , 4 ₄ , 4 ₅ , 4 ₆ . . . are connection lines;
D ₁ , D ₂ are diodes 17 ₄ , 17 ₅ . . . are check switching circuits which are essential parts of the present invention, and each is formed from the following parts to form the check switching circuit group 17 of the present invention. . S ₁₁ and S ₁₂ are switching transistors for flowing current from the connector contact to the contact direction to the connection line circuit under test, and S ₂₁ and S ₂₂ are switching transistors for flowing current from the connector contact to the contact direction, that is, the opposite direction, to the connection line circuit under test. switching transistor for passing current,
E ₁ and E ₂ are power supplies, and L ₁ and L ₂ are level detectors. 7 is a microcomputer, 11 is a memory circuit for setting a regular connection mode, 12 is a memory circuit for setting an operation management program, 8 is a keyboard for specifying an address, 9 is a single wire connection key, 10 is a blank wire connection key, 18, 19
are diode connection direction designation keys provided for the present invention, of which 18 are forward direction designation keys and 19 are reverse direction designation keys. For example, as shown in FIG. 2A, diodes D ₁ , If D ₂ is connected, write to the memory circuit 11 for setting the normal connection mode as follows, and write the diode insertion circuit of the check switching circuit group 17 built into the memory circuit 12 for setting the operation management program. It operates as follows based on the switching command word.

That is, first, after operating a write key (not shown), press [1] on the address designation keyboard 8, then press the single line connection key 9, [2] on the keyboard 8,
Empty wire connection key 10, keyboard 8 [3], single wire connection key 9, keyboard 8 [4], diode forward direction designation key 18, single wire connection key 9, keyboard 8 [5], diode reverse direction designation Key,
By operating the single line connection keys 9 in the order shown, the normal connection mode is set as shown in FIG. When starting the check, the start key 13 is operated. Then, up to contact number 4, the switching command signal _P1 is sent to the switching transistor _S11 ,
Turn this on given to the base of S ₁₂ . When 4 contacts are specified, a circuit is formed [positive polarity of power supply E ₁ → switch S ₁₁ → contact → diode D ₁ → side contact → switch S ₁₂ → negative polarity of power supply], and the direction from contact to contact is A current is passed through the connecting wire. When the contact number is designated as 5, instead of the switching command signal P ₁ from the microcomputer 7, P ₂ is applied to the switches S ₂₁ and S ₂₂ of the check switching circuit 17 to turn them on. Positive polarity of E ₂ → switch S ₂₁ → side contact → diode D ₂ →
Side contact → switch S ₂₂ → negative polarity of power supply E ₂ ]
A circuit is formed and a current is passed through the connecting wire 4 ₅ . Then, when the contact number becomes [6], _P1 is sent to the check switching circuit 17 again instead of the switching command signal _P2 .
In addition to this, a current flows from contact to contact, and level detectors L ₁ and L ₂ detect the current level and inform the microcomputer 7 as well as the normal connection mode set in the memory circuit 11. The output of the check switching circuit group 17 is compared. Similarly, it is possible to detect that the current is blocked by flowing the current from the opposite direction.

(Effects of the Invention) As described above, in the present invention, even when an element having a current blocking effect, such as a diode, is connected, the memory circuit for setting the normal connection mode can be set in advance by using a key corresponding to the connection direction of the diode. A check can be performed in the same manner as before by simply setting a switching command to specify the connection polarity of the set diode, and the checking function of the continuity test device can be expanded.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram of the wire harness, Figure 2 a,
b is an explanatory diagram of the connection state, Fig. 3 is an explanatory diagram of a conventional continuity test device, Fig. 4 is a check switching circuit diagram,
FIG. 5 is a process flow diagram, FIG. 6 is a diagram of an example of an apparatus for implementing the present invention, and FIG. 7 is an explanatory diagram of settings to the memory circuit. 1... Wire harness, 2... Vehicle body, 3... Connector, 4... Connection wire, 5... Connector group, 5 ₁ ,
5 ₂ ... Connector, 6... Test stand, 7... Microcomputer, 8... Address, keyboard for designation, 9... Single wire connection key, 10... Blank wire connection key, 11... For setting regular connection mode. memory circuit,
12...Memory circuit for setting operation management program,
13...Start key, 14...Return key, 15...
Check switching circuit group, 16...Display circuit, 17
...Check switching circuit group, 17 ₁ , 17 ₂ ~...
Check switching circuit, S ₁₁ , S ₁₂ , S ₂₁ , S ₂₂ ... switching transistor, E ₁ , E ₂ ... power supply, L ₁ ,
L ₂ ...Level detector, 18...Forward direction designation key,
19...Reverse direction designation key.

Claims (1)

[Claims] 1. The output signal of a processing circuit including a memory circuit for setting an operation management program and a memory circuit for setting a normal connection mode of the connection line circuit under test is sequentially switched to the connection line circuit under test. Apply current sequentially,
The output of the check switching circuit that sends out a signal indicating the connection state is compared with the contents written in the normal connection mode setting memory circuit according to a command from the processing circuit in a continuity test device to detect connection abnormalities. A wire harness testing device characterized in that the switching circuit is configured to allow current to flow in both forward and reverse directions through the connection line circuit under test. 2. The check switching circuit is connected to the first and second switch groups, and by switching them, one of the connection lines under test is connected.
the first and second power supplies connected to one end and the other end, and the first and second power supplies are configured to flow in the memory circuit for setting the operation management program in accordance with the insertion polarity of the current blocking element. 2. The wire harness testing device according to claim 1, further comprising a function of transmitting a command signal for switching the second changeover switch group.