CN216526238U

CN216526238U - Device for detecting whether FPC wiring is open-circuited

Info

Publication number: CN216526238U
Application number: CN202122316380.8U
Authority: CN
Inventors: 黄亮亮; 陈健立
Original assignee: Truly Opto Electronics Ltd
Current assignee: Truly Opto Electronics Ltd
Priority date: 2021-09-24
Filing date: 2021-09-24
Publication date: 2022-05-13
Anticipated expiration: 2031-09-24

Abstract

The utility model discloses a device for detecting whether FPC wiring is open-circuited, which comprises a signal generator, an inductor and an oscilloscope, wherein the signal output end of the signal generator is connected with the FPC driving channel wiring through the inductor, the FPC sensing channel wiring is connected with a probe of an oscilloscope probe, the grounding wire of the oscilloscope probe is connected with the output ground of the signal generator, and the oscilloscope probe is connected with an oscilloscope input channel. The utility model utilizes the capacitance and inductance of the capacitance key of the FPC to form an LC oscillating circuit, the signal generated by a signal generator is displayed on an oscilloscope through the LC oscillating circuit, if the FPC routing has no problem, the waveform is normally displayed, if the FPC routing is open-circuited, the oscilloscope can not display the waveform, during the test period, the FPC can be swung at different angles and the oscilloscope is observed, and the waveform is displayed only if the FPC is not open-circuited. The device simple structure, the test is convenient, can stop to walk the line and open a way the overlap joint after and cause the test result inaccurate.

Description

Device for detecting whether FPC wiring is open-circuited

Technical Field

The utility model belongs to the technical field of detection, and particularly relates to a device for detecting whether an FPC (flexible printed circuit) wiring is open-circuited.

Background

At present, a capacitive touch screen is commonly applied to equipment such as vehicle-mounted central control equipment, and as automobile manufacturers have extremely high requirements on the yield of vehicle-mounted product parts, the requirement on the yield of delivered products is close to 100%; therefore, it is the objective of the parts supplier to enhance the detection means, improve the product yield, and ensure that the good product rate of the parts delivered to the automobile manufacturer reaches 100%. However, in the conventional method for detecting the keys of the capacitive touch screen, the FPC is inserted and fixed on the test fixture, and then software is used for capturing data in the state to judge whether the wiring of the FPC is open-circuited. In an actual test, part of the FPC wiring is actually disconnected, but is still in a lap joint state in some states, and software still can be judged to be OK, so that a judgment error is caused, an abnormal product leaves a factory, and the detection yield and reputation of a factory product are affected.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem of providing a device for detecting whether the FPC wiring is open-circuited, which has a simple structure and is convenient to test, can detect the condition that the FPC wiring is open-circuited but is lapped, and greatly improves the yield after detection.

In order to solve the problems, the technical scheme adopted by the utility model is as follows:

a device for detecting whether an FPC wiring is open-circuited or not comprises a signal generator, an inductor and an oscilloscope, wherein a signal output end of the signal generator is connected with a driving channel of the FPC through the inductor to wiring, an induction channel of the FPC is wired and connected with a probe of an oscilloscope probe, a ground wire of the oscilloscope probe is connected with an output ground of the signal generator, and the oscilloscope probe is connected with an oscilloscope input channel.

Furthermore, the ground wire of the oscilloscope probe and the output ground of the signal generator are both connected with the ground wire of the FPC.

Furthermore, the device also comprises a socket matched with the FPC, and the socket is connected with the inductor and a probe of the oscilloscope probe.

Furthermore, the device also comprises a circuit board, the socket is welded on the circuit board, and pins of the socket are connected with the detection points through wiring on the circuit board.

Preferably, a probe seat is welded on the detection point, and a probe can be inserted into the probe seat to be fixed during measurement.

Furthermore, the inductance welding is on the circuit board, and inductance one end is through the line connection socket of walking on the circuit board, and the inductance other end is through the line connection pin plug of walking on the circuit board, and during the measurement, signal generator changes alligator clamp cable connection pin plug through BNC.

Furthermore, a ground wire is arranged on the circuit board and connected with a socket ground wire pin, a pin plug is welded on the ground wire, the pin plug is used for connecting a ground wire of the oscilloscope probe and an output ground of the signal generator, and the output ground of the signal generator is connected with the pin plug through a BNC-to-crocodile clamp cable.

Further, the circuit board is fixed on a certain platform.

Furthermore, an FPC swing device is further arranged on the platform and provided with a swing head, one end, far away from an FPC plug, of the FPC is fixed on the swing head, and the swing head swings to drive the FPC to swing.

Further, the signal generator is any one of a sine wave generator, a triangular wave generator, a sawtooth wave generator and a rectangular wave generator.

Adopt the produced beneficial effect of above-mentioned technical scheme to lie in:

the utility model utilizes the capacitance and inductance of the capacitance key of the FPC to form an LC oscillating circuit, the signal generated by a signal generator is displayed on an oscilloscope through the LC oscillating circuit, if the FPC routing has no problem, the waveform is normally displayed, if the FPC routing is open-circuited, the oscilloscope can not display the waveform, during the test period, the FPC can be swung at different angles and the oscilloscope is observed, and the waveform is displayed only if the FPC is not open-circuited. And then can judge and walk the line and open circuit, the device simple structure, the test is convenient, can stop to walk the line and open circuit the back lap joint cause test result inaccurate.

Drawings

FIG. 1 is a block diagram of the present invention;

FIG. 2 is a waveform diagram of FPC trace connectivity according to the present invention;

fig. 3 is a waveform diagram of an open circuit of the FPC trace according to the present invention.

Detailed Description

The utility model is described in further detail below with reference to the attached drawings:

the utility model relates to a device for testing whether an FPC (flexible printed circuit) wiring is open-circuited, which is particularly used for an FPC with a capacitive key. The utility model utilizes the capacitance of the capacitance key of the FPC and the external inductor to form a series LC oscillating circuit, the circuit is externally connected with a signal generator and an oscilloscope, the signal generator provides an input signal for the oscillating circuit, and the input signal is displayed on the oscilloscope through the LC oscillating circuit. If the FPC wiring is open-circuited, the signal path is disconnected, the oscilloscope cannot detect the waveform, if the FPC wiring is connected, the signal enters the oscilloscope for displaying, so that whether the FPC wiring is open-circuited can be judged, during testing, the FPC wiring is swung at different angles and the oscilloscope is observed, and the condition that the FPC wiring is disconnected and is lapped in a certain state can be tested. And further, the products with broken FPC wiring and lap joint can be checked, and the yield of products leaving factories is improved.

Example 1

As shown in fig. 1, the device for testing whether the FPC lines are open circuit or not according to this embodiment includes a signal generator, an inductor, and an oscilloscope, for the FPC with capacitive keys, each capacitive key is connected to a plug of the FPC through a line so as to be connected to a main board and the like through the plug, each capacitor has at least one driving channel line and one sensing channel line, and the driving lines of all the capacitors may be combined into one line. For this embodiment, the signal output end of the signal generator is connected to the drive channel of the FPC through an inductor, the sensing channel of the FPC is connected to the probe of the oscilloscope probe, the ground wire of the oscilloscope probe is connected to the output ground of the signal generator, and the oscilloscope probe is connected to the input channel of the oscilloscope.

In order to make the test more reliable, the ground wire of the oscilloscope probe and the output ground of the signal generator are both connected with the ground wire of the FPC. For the convenience of measurement, the device of this embodiment further includes a socket matched with the FPC, and the socket is connected with the inductor and the probe of the oscilloscope probe.

In order to facilitate measurement and prevent an accident situation that the FPC and the inductor are not fixed during measurement, the device further comprises a circuit board, the socket is welded on the circuit board, and pins of the socket are connected with the detection points through wiring on the circuit board. And a probe seat is welded on the detection point, and a probe can be inserted into the probe seat to be fixed during measurement. The inductance welding is on the circuit board, and inductance one end is through walking on the circuit board and line connection socket, and the inductance other end is through walking on the circuit board and line connection pin type plug, and during the measurement, signal generator changes alligator clip cable connection pin type plug through BNC. The ground wire wiring is arranged on the circuit board and connected with a socket ground wire pin, a pin plug is welded on the ground wire, the pin plug is used for connecting the ground wire of the oscilloscope probe and the output ground of the signal generator, and the output ground of the signal generator is connected with the pin plug through a BNC-to-crocodile clamp cable. And the circuit board is fixed on a certain platform. Therefore, the oscilloscope probe, the inductor, the connecting wire and the like are fixed, other devices, cables and the like are not influenced when the FPC is swung, and the measurement is convenient, stable and reliable.

During testing, the detection device is configured according to the technical scheme and connected with the FPC, the waveform of the oscilloscope is observed, when the capacitive button routing of the FPC is intact and has no open circuit, the waveform is always as shown in figure 2 no matter how the FPC swings, and the voltage amplitude is close to +/-1V; when the capacitance key wiring of the FPC is open-circuited, the waveform is as shown in FIG. 3, the voltage amplitude is close to 0V, and when the FPC is swung to a certain angle, if the waveform shown in FIG. 3 appears, the condition that the wiring of the FPC is open-circuited but lapped is explained, and the FPC in the condition is also unqualified.

Example 2

The present embodiment differs from the embodiment in that: in order to realize the test automation, reduce the human labor, this embodiment is in still set up FPC pendulous device on the platform, FPC pendulous device is equipped with the swing head, FPC keeps away from the one end of FPC plug and fixes on the swing head, and the swing head swing drives the FPC swing.

For the above embodiments, the signal generator of the present invention may be any one of a sine wave generator, a triangular wave generator, a sawtooth wave generator, and a rectangular wave generator.

Claims

1. The utility model provides a detect FPC and walk device whether open circuit of line which characterized in that: the device comprises a signal generator, an inductor and an oscilloscope, wherein the signal output end of the signal generator is connected with a drive channel of the FPC through the inductor for wiring, an induction channel of the FPC is wired and connected with a probe of an oscilloscope probe, an earth wire of the oscilloscope probe is connected with the output ground of the signal generator, and the oscilloscope probe is connected to an oscilloscope input channel.

2. The device of claim 1, wherein the device for detecting whether the FPC trace is open-circuited comprises: and the ground wire of the oscilloscope probe and the output ground of the signal generator are both connected with the ground wire of the FPC.

3. The device of claim 1, wherein the device for detecting whether the FPC trace is open-circuited comprises: the device also comprises a socket matched with the FPC, and the socket is connected with the inductor and a probe of the oscilloscope probe.

4. The device of claim 3, wherein the device for detecting whether the FPC trace is open-circuited comprises: the device also comprises a circuit board, the socket is welded on the circuit board, and pins of the socket are connected with the detection points through wiring on the circuit board.

5. The device of claim 4, wherein the device for detecting whether the FPC trace is open-circuited is characterized in that: and a probe seat is welded on the detection point, and a probe can be inserted into the probe seat to be fixed during measurement.

6. The device of claim 4, wherein the device for detecting whether the FPC trace is open-circuited is characterized in that: the inductance welding is on the circuit board, and inductance one end is through walking on the circuit board and line connection socket, and the inductance other end is through walking on the circuit board and line connection pin type plug, and during the measurement, signal generator changes alligator clip cable connection pin type plug through BNC.

7. The device of claim 4, wherein the device for detecting whether the FPC trace is open-circuited is characterized in that: the ground wire wiring is arranged on the circuit board and connected with a socket ground wire pin, a pin plug is welded on the ground wire, the pin plug is used for connecting the ground wire of the oscilloscope probe and the output ground of the signal generator, and the output ground of the signal generator is connected with the pin plug through a BNC-to-crocodile clamp cable.

8. The device of claim 7, wherein the device for detecting whether the FPC trace is open-circuited comprises: the circuit board is fixed on a certain platform.

9. The device of claim 8, wherein the device for detecting whether the FPC trace is open-circuited comprises: still set up FPC pendulous device on the platform, FPC pendulous device is equipped with the swing head, FPC keeps away from the one end of FPC plug and fixes on the swing head, and the swing of swing head drives the FPC swing.

10. The device of claim 1, wherein the device for detecting whether the FPC trace is open-circuited comprises: the signal generator is any one of a sine wave generator, a triangular wave generator, a sawtooth wave generator and a rectangular wave generator.