JPH06222110A - Fixture - Google Patents

Abstract

PURPOSE:To produce no inferior product due to contact failure of a probe and a solder by providing one pair of probes which contact with a solder and are electrically insulated each other, switching relays to be connected with respective probes, a control unit, etc. CONSTITUTION:A lead wire 3 of a part 2 mounted on a board 1 to be tested is electrically and mechanically connected with the board 1 by a solder 4. Probes A, B which contact with the solder 4 and are electrically insulated each other are connected with cables A, B and the cables A, B are connected with a contact judging part 9. A switching relay to switch between the case that contact of the probes is judged and the case that a test is carried out is installed in the judging part 9, and a test or contact judgement is carried out by switching the contact point of the switching relay by a control unit.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to fixtures.

[0002]

2. Description of the Related Art A conventional fixture comprises a substrate under test,
The component mounted on the board under test, the lead wire of the component, the solder for fixing the lead wire and for conducting the electrical connection between the mounted components, and the pair of the probe A and the probe in contact with the solder B, and a cable A and a cable B connected to each probe.

As a conventional method for inspecting a circuit board on which electronic components are mounted, a signal flowing on the circuit board is directly taken out from the circuit board or is supplied to determine whether the signal on the circuit board is normal or not. Inspection at the circuit board stage is performed. At this time, a specific jig (fixture) for taking out a signal from the circuit board or supplying a signal depending on the type of the circuit board is also required according to the type of the circuit board.

Next, a conventional fixture will be described in detail with reference to the drawings.

FIG. 3 is a schematic view showing a conventional example. The fixture shown in FIG. 3 is for fixing the lead substrate 3 of the component under test 1, the component 2 mounted on the substrate under test 1, the lead wire 3 of the component, and the conduction between the mounted components. Of solder 4, a pair of probes A5 and B6 that come into contact with the solder 4, and a cable A7 and a cable B8 connected to the respective probes.

Here, the signal flowing through the substrate under test 1 is directly taken out from the substrate under test 1 via the probe A, the probe B, the cable A and the cable B, or the signal is supplied so that the signal of the substrate under test 1 is detected. Inspection is performed at the circuit board stage for determining whether or not the circuit is normal. This signal is processed to determine the quality of the substrate under test. When the test of one test substrate is completed, the next test substrate is placed and the test is performed again. Therefore, the substrate under test is frequently replaced.

[0007]

SUMMARY OF THE INVENTION The above-mentioned conventional fixture has a structure in which a test result is defective due to a cause inside the board under test, such as a component failure on the board under test, and a probe, In some cases, the test result may be poor due to poor contact with the solder, and in the latter case, there is a risk that the board under test may be defective even if it is normal.

[0008]

The fixture of the present invention comprises a substrate to be tested, a component mounted on the substrate to be tested, lead wires of the component, and the fixed and mounted lead wires of the component. Solder for conducting electrical connection between components, a set of probes A and B that are in contact with the solder and electrically insulated from each other, and a cable A connected to the probe A and the probe B, respectively. And cable B, switching relay A and switching relay B respectively connected to cable A and cable B for switching between contact determination and test, a pull-up resistor, an interface unit, and an interface unit. A control unit for controlling the switching relay and the display LED according to the information from the display and the display LED
And an LED drive unit for lighting.

[0009]

Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic diagram showing an embodiment of the present invention, and FIG. 2 is a block diagram of the contact determination section 9 shown in FIG. Figure 1
The fixture shown in FIG.
The component 2 mounted thereon, the lead wire 3 of the component, the solder 4 for fixing the lead wire 3 and for conducting the conduction between the mounted components, and being in contact with and electrically insulated from the solder 4. A set of probe A5 and probe B6, a cable A7 and a cable BR connected to each probe A5 and probe B6, and a switching relay A11 for switching between contact determination and test. Relay B12, pull-up resistor 13, interface unit 14, interface unit 1
Control of switching relay and display LED according to information from 4
And a LED drive unit 16 for turning on the display LED 10.

Here, the lead wire 3 of the component 2 mounted on the board under test 1 is electrically and mechanically coupled to the board under test 1 by the solder 4. There is a probe A and a probe B insulated from each other that are in contact with the solder 4, and a cable A connected to each probe,
There is a cable B, which is connected to the contact determination unit 8. A switching relay A and a switching relay B for switching between the contact determination of the probe and the test are provided in the contact determination unit 8 and are provided by the control unit 13 on the contact side b or the side c of the switching relay. You can switch to either.
In the case of the in-relay contact b side, the test connected to the tester can be performed. In the case of the in-relay contact c side, it is connected to the contact determination unit 9 that determines the contact between the solder 4 and the probe A and the probe B, and the contact determination can be performed.

First, contact judgment is performed before the test. The switching relay A and the switching relay B are set on the contact c side. The setting of the switching relay is performed through the interface unit 14 under the control of the control unit 15. Here, the probe A5 and the probe B6 are solder 4
When electrically connected through the pull-up resistor 13
From + 5V connected to the pull-up resistor 13, contact c of switching relay A, contact a, cable A7, probe A
5, solder 4, probe B6, cable B8, contact a of contact B, switching contact c, GND connected to contact c
Are electrically connected in this order, a voltage drop occurs at the contact c of the switching relay A11 according to the resistance value of the pull-up resistor, and has a voltage value obtained by subtracting the voltage drop voltage from + 5V.

On the contrary, when the probe A5 and the probe B6 are not electrically connected through the solder 4, the contact point c of the switching relay A11 has the voltage value of +5 V connected as it is. The interface unit 14 informs the control unit 15 whether or not the probes A5 and B6 are electrically connected via the solder 4 from two different voltage values generated at the contact c of the switching relay A11. When the probe A5 and the probe B6 are electrically connected via the solder 4, the control unit 15 causes the LED drive unit 16 to turn on the display LED 10.

On the contrary, when the probe A5 and the probe B6 are not electrically connected to the electric drop through the solder 4, the display LED 10
Does not light up. After confirming the lighting of the display LED 10, the operator gives a command to the control unit 15 and switches the contacts of the switching relay A and the switching relay B to the side b through the interface unit 14. In this case, the solder 4 of the substrate under test 1 is connected to the tester through the probe A5, the probe B6, the cable A and the cable B connected to the respective probes, and the switching relay A and the switching relay B.

[0015]

According to the fixture of the present invention, it is possible to test the substrate under test after confirming whether the probe A and the probe B are in contact with the solder (electrically conducting). Therefore, there is an effect that there is no case where the test result becomes defective due to the poor contact between the probe and the solder.

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment of the present invention.

FIG. 2 is a block diagram of a contact determination unit 9 in FIG.

FIG. 3 is a schematic diagram showing a conventional example.

[Explanation of symbols]

 1 Test Board 2 Parts 3 Lead Wire 4 Solder 5 Probe A 6 Probe B 7 Cable A 8 Cable B 9 Contact Judgment Section 10 Display LED 11 Switching Relay A 12 Switching Relay B 13 Pull-up Resistor 14 Interface Unit 15 Control Unit 16 LED Drive unit

Claims (1)

[Claims] 1. A substrate under test, a component mounted on the substrate under test, a lead wire of the component, and a solder for fixing the lead wire and for conducting electrical connection between the mounted components. A set of probes A and B that are in contact with the solder and electrically insulated from each other, and a cable A that is connected to the probes A and B, respectively.
And a cable B, and a switching relay A and a switching relay B respectively connected to the cable A and the cable B for switching between contact determination and test.
, Pull-up resistor, interface unit,
A control unit for controlling the switching relay and the display LED according to information from the interface unit;
A fixture comprising: an LED drive unit for turning on the display LED.