Leakage current detection type PCBA test circuit and device

Abstract

The utility model discloses a leakage current detection type PCBA test circuit and equipment. The leakage current detection type PCBA test circuit comprises a test current signal output unit, a test voltage signal output unit and a test result signal output unit, the test current signal output unit is used for outputting a leakage current detection current signal; the test current signal output unit is provided with a current adjusting circuit, and the current adjusting circuit is used for adjusting the value of the leakage current detection current signal. The test voltage signal output unit is used for outputting a leakage current detection voltage signal; the test voltage signal output unit is provided with a voltage adjusting circuit, and the voltage adjusting circuit is used for adjusting the value of the leakage current detection voltage signal. The leakage current detection current signal and the leakage current detection voltage signal are used for being loaded to a PCBA to be detected; when the PCBA receives the leakage current detection current signal and the leakage current detection voltage signal, a leakage current protection signal is output; the test result output unit is configured to output a test result signal when the leakage current protection signal is received.

Description

Technical Field

[0001] This utility model relates to the field of testing equipment technology, and in particular to a leakage current detection type PCBA test circuit and equipment. Background Technology

[0002] Currently, in the low-voltage electrical appliance industry, the testing of leakage current detection PCBAs (Printed Circuit Board Assemblies) mainly involves using a self-made simple fixture to hold the product in place, followed by manual interaction with electrical signals via a testing platform. The reliability of the leakage current detection PCBA is then determined manually based on electrical parameters. However, the limitations of the equipment and testing methods, coupled with the need for manual intervention, result in limited testing coverage, cumbersome operations, and long testing cycles, leading to low testing efficiency and low return on investment. Utility Model Content

[0003] This invention provides a leakage current detection type PCBA test circuit and device to improve the automation of PCBA test equipment.

[0004] This utility model embodiment provides a leakage current detection type PCBA test circuit, including:

[0005] Test current signal output unit, test voltage signal output unit and test result signal output unit;

[0006] The test current signal output unit is used to output a leakage current detection current signal;

[0007] The test current signal output unit is equipped with a current adjustment circuit, which is used to adjust the value of the leakage current detection current signal.

[0008] The test voltage signal output unit is used to output a leakage current detection voltage signal;

[0009] The test voltage signal output unit is equipped with a voltage adjustment circuit, which is used to adjust the value of the leakage current detection voltage signal.

[0010] The leakage current detection current signal and the leakage current detection voltage signal are used to be applied to the PCBA to be tested;

[0011] When the PCBA receives the leakage current detection current signal and the leakage current detection voltage signal, it outputs a leakage current protection signal.

[0012] The test result output unit is configured to output a test result signal when the leakage current protection signal is received. The test result signal is used to indicate that the PCBA has passed the leakage current test.

[0013] Optionally, the test current signal output unit includes a first transformer and at least one current signal output branch;

[0014] The current signal output branch includes a numerically adjustable current-limiting resistor, a first relay, and a magnetic ring;

[0015] The first winding terminal of the first transformer is electrically connected to the power supply. The current-limiting resistor is connected in series with the normally open contact of the first relay to form a first circuit with the second winding terminal of the first transformer. The wire of the first circuit passes through the magnetic ring.

[0016] The output terminal of the magnetic ring is used to output the leakage current detection current signal.

[0017] Optionally, the test current signal output unit further includes an ammeter, which is connected in series in the first circuit;

[0018] The ammeter is used to display the value of the current in the first circuit.

[0019] Optionally, the test voltage signal output unit includes at least one voltage signal output branch;

[0020] The voltage signal output branch includes a voltage regulating motor, a voltage regulator, a second relay, a third relay, and a voltage regulating controller;

[0021] The voltage regulation signal output terminal of the voltage regulator controller is electrically connected to the voltage regulation motor, and the voltage regulation signal output terminal is used to output a voltage regulation signal;

[0022] The voltage regulating motor is connected to the voltage regulator, and the voltage regulating motor is used to adjust the output voltage of the voltage regulator according to the voltage regulation signal;

[0023] The first winding of the voltage regulator is electrically connected to the power supply, and the second winding of the voltage regulator is connected to the voltage output terminal through the normally open contact of the second relay.

[0024] The voltage output terminal is used to connect to the leakage current detection voltage output terminal, and the leakage current detection voltage output terminal is used to output the leakage current detection voltage signal;

[0025] The coil of the second relay and the normally open contact of the third relay form a second circuit, and the first control terminal of the voltage regulator is electrically connected to the coil of the third relay.

[0026] Optionally, the test voltage signal output unit further includes a reversing switch;

[0027] The reversing switch is located at the voltage output terminal, and the second control terminal of the voltage regulator is electrically connected to the reversing switch.

[0028] The reversing switch is used to switch the voltage output terminal to output a first voltage or a second voltage.

[0029] Optionally, the test result output unit includes a fourth relay, a fifth relay, a sixth relay, and a seventh relay;

[0030] The fourth relay and the fifth relay form a power-on self-locking structure. When the fourth relay is powered on, the fifth relay self-locks. When the fifth relay self-locks, the voltage output terminal remains continuously connected.

[0031] The sixth relay and the seventh relay constitute a tripping structure, and the two ends of the leakage current protection signal input terminal are connected in series with the coil of the sixth relay.

[0032] The leakage current protection signal input terminal is used to receive the leakage current protection signal, and the sixth relay is configured to power on when the PCBA outputs the leakage current protection signal.

[0033] When the sixth relay is powered on, the fifth relay is disconnected, the seventh relay is self-locked, and when the seventh relay is self-locked, the test result output unit continuously outputs the test result signal.

[0034] Optionally, the voltage output terminal includes a first output terminal and a second output terminal, and the leakage current detection voltage output terminal includes a third output terminal, a fourth output terminal, and a fifth output terminal;

[0035] The first output terminal is electrically connected to the third output terminal, and the second output terminal is electrically connected to the fourth or fifth output terminal.

[0036] The test result output unit also includes a switching switch, which is used to electrically connect the second output terminal to the fourth output terminal or to the fifth output terminal.

[0037] Optionally, the test result output unit may further include a shunt resistor and an eighth relay;

[0038] One end of the leakage current protection signal input terminal is also connected in series with the normally closed contact of the eighth relay and the normally closed contact can be switched, and the normally open contact of the eighth relay is also connected in series with the shunt resistor.

[0039] Optionally, the output voltage of the third and fourth output terminals includes 220V, and the output voltage of the third and fifth output terminals includes 380V.

[0040] Secondly, this utility model embodiment provides a leakage current detection type PCBA test device, including any of the test circuits described in this utility model embodiment, and also includes a controller;

[0041] The controller is connected to the test current signal output unit, the test voltage signal output unit, and the test result signal output unit;

[0042] The controller is used to adjust the value of the leakage current detection current signal by controlling the test current signal output unit, adjust the value of the leakage current detection voltage signal by controlling the test voltage signal output unit, and receive the test result signal by the test result signal output unit.

[0043] Optionally, a touch screen is also included, which is electrically connected to the controller and is used to communicate and interact with the controller, input test commands, and display test results.

[0044] The input test command is used to adjust the value of the leakage current detection current signal and the value of the leakage current detection voltage signal.

[0045] Optionally, it also includes: a clamping linkage device, which is used to fix the leakage current detection type PCBA to be tested.

[0046] Optionally, the clamping linkage device includes: a dual-axis cylinder, a limit switch, a press, a pressure bar, and a carrier plate;

[0047] The press is mechanically connected to the twin-axis cylinder via a connecting plate, and the press is used to provide the mounting points for the pressure bar;

[0048] The limit switch is used for monitoring the movement position of the press.

[0049] The carrier board is used to support the leakage current detection type PCBA.

[0050] Optionally, it may also include: a probe device, the probe device comprising: a needle bed and a probe;

[0051] The carrier plate is movably mounted above the needle bed, and the probe is mounted on the needle bed. The probe is used to inject a leakage current detection signal into the leakage current detection type PCBA to be tested.

[0052] Optionally, it also includes: a rack and a slide rail drawer, wherein the slide rail drawer is slidably connected to the rack and the slide rail drawer is used to house intermediate relays and AC contactors in the test circuit;

[0053] The controller is electrically connected to the intermediate relay, and the controller controls the operation of the AC contactor through the intermediate relay.

[0054] Optionally, it also includes: a safety light curtain, the safety light curtain being disposed on the frame;

[0055] The controller is connected to the safety light curtain, and the controller is configured to stop the leakage current test according to the safety detection signal of the safety light curtain;

[0056] If a person or object enters the leakage current test area, the safety light curtain generates the safety detection signal.

[0057] Compared with existing technologies, the advantages of this invention are as follows: The testing equipment proposed in this invention, through the coordinated operation of the test current signal output unit, the test voltage signal output unit, and the test result signal output unit, can automatically output precisely matched leakage current detection current and voltage signals to be applied to the PCBA under test. After the PCBA responds, it outputs a leakage current protection signal, and the test result output unit automatically provides the test result. The entire process requires minimal manual intervention, greatly reducing the degree of human involvement, especially for offline testing equipment, significantly improving testing efficiency and accuracy.

[0058] The configured current and voltage regulation circuits can flexibly adjust the test signal values ​​according to the characteristics and testing requirements of different PCBA products. Regardless of the product type, it can be quickly adapted, easily resolving compatibility issues and ensuring high flexibility in testing modes to meet diverse production and testing needs. Attached Figure Description

[0059] Figure 1 This is a block diagram of the leakage current detection type PCBA test circuit structure in the embodiment;

[0060] Figure 2 This is a schematic diagram of the test current signal output unit structure in the embodiment;

[0061] Figure 3 This is a schematic diagram of the test voltage signal output unit structure in the embodiment;

[0062] Figure 4 This is a schematic diagram of the test result output unit structure in the embodiment;

[0063] Figure 5 This is a schematic diagram of the front structure of the test equipment in the embodiment;

[0064] Figure 6 This is a partial structural diagram of the operating area of ​​the test equipment in the embodiment;

[0065] Figure 7 This is a schematic diagram of the front structure of the test equipment in the embodiment;

[0066] Figure 8 This is a schematic diagram of a partial internal structure of the test equipment in the embodiment. Detailed Implementation

[0067] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0068] Figure 1 This is a block diagram of the leakage current detection type PCBA test circuit in the embodiment. The circuit includes a test current signal output unit 100, a test voltage signal output unit 200, and a test result signal output unit 300.

[0069] The test current signal output unit 100 is used to output a leakage current detection current signal. The test current signal output unit 100 is equipped with a current adjustment circuit, which is used to adjust the value of the leakage current detection current signal.

[0070] The test voltage signal output unit 200 is used to output a leakage current detection voltage signal. The test voltage signal output unit 200 is equipped with a voltage adjustment circuit, which is used to adjust the value of the leakage current detection voltage signal.

[0071] The leakage current detection current signal and leakage current detection voltage signal are applied to the PCBA 1000 under test; when the PCBA receives the leakage current detection current signal and leakage current detection voltage signal, it outputs a leakage current protection signal.

[0072] The test result output unit 300 is configured to output a test result signal when a leakage current protection signal is received. The test result signal is used to indicate that the PCBA has passed the leakage current test.

[0073] In this solution, the leakage current detection PCBA (Printed Circuit Board Assembly) is a key component installed inside the residual current device (RCD), possessing leakage current detection and judgment functions. The leakage current detection PCBA can monitor the load circuit in real time. When a short circuit or leakage current occurs, it can activate the trip unit based on the detection information to promptly disconnect the load circuit, ensuring the safety of equipment and personnel.

[0074] To ensure reliable performance, its leakage current detection and drive functions must be rigorously tested. During testing, specific voltage and current signals are applied to the PCBA to simulate leakage conditions, and the PCBA's ability to accurately detect leakage current and drive the trip unit is observed. If the PCBA responds promptly and cuts off the circuit during the test, it indicates that its function is normal.

[0075] In this solution, the leakage current detection type PCBA test equipment is used for functional testing of leakage current detection type PCBA, that is, to test its leakage current detection function and driving function.

[0076] For example, in this solution, the leakage current detection current signal is a current signal applied to match the leakage current detection PCBA. Its function is to simulate the current conditions that may occur in actual operation, creating conditions for leakage current detection.

[0077] Specifically, in real-world applications, leakage current conditions are complex and varied, with different magnitudes, frequencies, and phases. Leakage current detection signals can be used to simulate the actual working environment that a PCBA might be in during real-world operation.

[0078] For example, some electrical equipment may experience leakage current fluctuations in specific frequency and amplitude due to electromagnetic interference during operation. Leakage current detection signals can simulate such complex situations, allowing the PCBA to operate in the same environment as in real-world conditions during testing, thus ensuring that the test results accurately reflect its performance.

[0079] Different models and specifications of leakage current detection PCBAs have different characteristics in terms of leakage current detection circuit sensitivity, response threshold, and detection frequency band. By adjusting the signal characteristics of the leakage current detection current signal (such as signal amplitude and frequency range), it can be precisely matched with the detection characteristics of the PCBA under test.

[0080] For example, a PCBA sensitive to low-frequency leakage current can adjust the output of a low-frequency leakage current detection signal with an amplitude that matches its detection range, ensuring that the PCBA can effectively detect and respond to leakage current and accurately evaluate its leakage current detection function.

[0081] For example, in this solution, the leakage current detection voltage signal serves as the excitation source for triggering and detecting the leakage current response of the PCBA. During testing, the leakage current detection voltage signal is applied to the PCBA. If the PCBA has a potential leakage current issue, a change in leakage current will occur under the influence of this signal.

[0082] By monitoring the PCBA's response to test electrical signals, such as whether it can accurately detect leakage current and promptly drive the trip unit, the performance of the PCBA can be determined to meet the requirements.

[0083] For example, if the PCBA can detect leakage current and perform tripping operation as designed after a test electrical signal of a specific amplitude and frequency is applied, it means that its leakage current detection and drive functions are normal.

[0084] In this solution, the parameters of the leakage current detection voltage signal can be flexibly adjusted, including the upper and lower limits of the voltage, the magnitude of the current, and the phase of the signal. By precisely adjusting these parameters, various complex leakage current conditions can be simulated, comprehensively testing the performance of the PCBA under different conditions.

[0085] For example, for PCBAs with different sensitivity requirements, the amplitude of the test electrical signal can be adjusted so that it just reaches or slightly exceeds the leakage current detection threshold of the PCBA, thereby more accurately testing its detection accuracy and response speed.

[0086] For example, in this solution, a current regulation circuit can be designed based on a potentiometer. The resistance value of the potentiometer can be continuously adjusted within a certain range, meeting the needs for fine current regulation. A sampling resistor can also be configured to calculate the current value in the circuit, providing feedback for current regulation.

[0087] Alternatively, a current regulation circuit can be designed based on a digital potentiometer and a DAC (Digital to Analog Converter). The digital potentiometer controls the resistance value via a digital signal. The DAC converts the digital signal into a precise analog voltage signal, which is then used to control the resistance value of the digital potentiometer.

[0088] In this scheme, a microcontroller can be configured to generate control signals to control the DAC output different voltage values, thereby indirectly adjusting the resistance of the digital potentiometer. The microcontroller's control interface is connected to the corresponding control interface of the DAC for transmitting digital control signals. The analog output of the DAC is connected to the control terminal of the digital potentiometer to control its resistance value.

[0089] For example, in this solution, a voltage regulation circuit can be designed based on a transformer and a linear regulator. The transformer can be configured to achieve initial voltage regulation by changing the tap positions. A linear regulator is then used to further stabilize and finely regulate the voltage output from the transformer. The adjustment terminal of the linear regulator can be connected to a potentiometer, allowing the output voltage of the linear regulator to be changed by adjusting the potentiometer.

[0090] For example, in this solution, the leakage current protection signal is an electrical signal output by the leakage current detection type PCBA when leakage current is detected. This electrical signal can be used to drive the trip unit of the PCBA.

[0091] For example, in this solution, the test result output unit 300 may include a trip unit, which may be designed in the same way as the trip unit configured in the leakage current detection type PCBA.

[0092] For example, in this solution, during the leakage current detection process, if the leakage current detection and judgment function of the PCBA is normal (for example, it can drive the trip unit to operate according to the design requirements when leakage current is detected), the PCBA will output a leakage current protection signal.

[0093] After receiving the leakage current protection signal, the test result signal output unit performs internal logic judgment and processing to generate a test result signal. The test result signal indicates that the PCBA's leakage current detection function and drive tripping function meet expectations under the current test conditions.

[0094] For example, in this solution, an input interface adapted to leakage current protection signals can be designed, a microcontroller can be configured to connect to the input interface, and the microcontroller can be configured to trigger the corresponding judgment logic when it receives a leakage current protection signal.

[0095] The microcontroller can be configured to output a test result signal as a high level or a low level, thereby indicating whether the PCBA has passed or failed the test.

[0096] This embodiment proposes a testing device, including a test current signal output unit, a test voltage signal output unit, and a test result output unit. The current adjustment circuit of the test current signal output unit can flexibly adjust the leakage current detection current signal value as needed; the voltage adjustment circuit of the test voltage signal output unit can precisely adjust the leakage current detection voltage signal value. This allows the device to provide suitable test electrical signals according to the characteristics and testing requirements of different PCBAs, greatly improving the targeting and accuracy of the test, avoiding misjudgments caused by signal mismatch, and enabling more accurate detection of the PCBA's leakage current performance.

[0097] When the test result output unit receives the leakage current protection signal from the PCBA, it automatically outputs a test result signal indicating that the PCBA has passed the test. This automated judgment mechanism requires minimal manual intervention, greatly reducing the time and effort costs of manual judgment and significantly improving test efficiency. It is especially suitable for batch testing scenarios in large-scale production.

[0098] exist Figure 1 Based on the scheme shown, in one possible implementation, the test current signal output unit includes a first transformer and at least one current signal output branch.

[0099] The current signal output branch includes a current-limiting resistor with adjustable value, a first relay, and a magnetic ring.

[0100] The first winding terminal of the first transformer is electrically connected to the power supply. The current-limiting resistor is connected in series with the normally open contact of the first relay to form a first circuit with the second winding terminal of the first transformer. The wires of the first circuit pass through the magnetic ring.

[0101] The output terminal of the magnetic ring is used to output a leakage current detection current signal.

[0102] In this design, the first transformer serves as both a voltage converter and an electrical isolation unit. Its first winding is electrically connected to the power supply, transferring electrical energy to the transformer. Through electromagnetic induction, an induced electromotive force is generated at the second winding, providing a suitable voltage for subsequent circuits. Simultaneously, it achieves electrical isolation between the test circuit and the power supply, enhancing safety.

[0103] In this scheme, the current signal output branch consists of a current-limiting resistor, a first relay, and a magnetic ring, which is the key part used to generate and output the leakage current detection current signal.

[0104] The value of the current-limiting resistor is adjustable. It is connected in series with the normally open contact of the first relay and forms the first circuit with the second winding terminal of the first transformer.

[0105] The main function of a current-limiting resistor is to limit the current in the circuit. By adjusting its resistance value, the value of the output leakage current detection signal can be precisely controlled to meet the testing requirements of different PCBAs.

[0106] The normally open contact of the first relay acts as a switch in the circuit. When the relay is energized, the normally open contact closes, allowing the current-limiting resistor to be connected to the first circuit. Current can flow through the circuit formed by the current-limiting resistor, the normally open contact of the first relay, and the second winding of the first transformer. When the relay is de-energized, the normally open contact opens, the circuit is cut off, and the current output stops.

[0107] In this scheme, the wires of the first circuit pass through the magnetic ring. The magnetic ring uses the principle of electromagnetic induction to convert the current signal in the circuit into a magnetic signal, and then converts the magnetic signal into an electrical signal for output. When current flows through the first circuit, a magnetic field is generated in the magnetic ring. According to the law of electromagnetic induction, the magnetic ring will induce an electromotive force, thereby outputting a leakage current detection current signal at its output terminal.

[0108] When the power is turned on, the first winding of the first transformer is energized, generating an induced voltage at the second winding. If the first relay is energized, its normally open contact closes, and the current flows from the second winding of the first transformer, through the current-limiting resistor and the normally open contact of the first relay, back to the second winding of the first transformer, forming a closed circuit.

[0109] During this process, as current flows through the circuit, the wire passing through the magnetic ring will induce an electromotive force in the magnetic ring, which will then output a leakage current detection signal at the output end of the magnetic ring. This signal can be applied to the PCBA under test for leakage current detection.

[0110] In this solution, a probe can be electrically connected to a magnetic ring, and the probe can pick up the output signal (leakage current detection signal) of the magnetic ring. This signal is then applied to a designated port of the PCBA under test through the probe, thereby simulating electromagnetic interference signals that may occur in actual operation.

[0111] Figure 2 This is a schematic diagram of the test current signal output unit structure in the embodiment, for reference. Figure 2 Based on any of the aforementioned schemes, the test current signal output unit may include three current signal output branches.

[0112] The test current signal output unit includes a first transformer T1 (9V transformer), a first current signal output branch, a second current signal output branch, and a third current signal output branch.

[0113] The power supply AC is electrically connected to the first winding terminal of the first transformer T1 through the leakage current switch K1.

[0114] (First) The current-limiting resistor R1 is connected in series with the normally open contact of the (first) first relay KA1, and forms a first circuit with the second winding terminal of the first transformer T1. The wires of the first circuit pass through the magnetic ring (not shown in the figure).

[0115] (Second) The current-limiting resistor R2 is connected in series with the normally open contact of the (second) first relay KA2, and forms a second circuit with the second winding terminal of the first transformer T1. The wires of the second circuit pass through the magnetic ring.

[0116] (Third) The current-limiting resistor R3 is connected in series with the normally open contact of the (third) first relay KA3, and together with the second winding terminal of the first transformer T1, they form a third circuit. The wires of the third circuit pass through the magnetic ring.

[0117] For example, in this solution, the resistance values ​​of current-limiting resistors R1, R2, and R3 can be configured to correspond to the upper limit current, lower limit current, and rated current of the leakage current detection current signal, respectively, and the first relay in the corresponding circuit can be configured to control the on / off state of the corresponding circuit.

[0118] In this scheme, the AC (220V) power supply is connected to the input terminal of the first transformer T1, and three potentiometers (current limiting resistor R1, current limiting resistor R2, and current limiting resistor R3) are connected in parallel to the output terminal of the first transformer T1. Each potentiometer is controlled by a normally open contact of a first relay to control its circuit opening and closing. The first relays are configured to be controlled by a controller (e.g., PLC) to open and close, and only one of the three first relays can be activated at the same time.

[0119] By applying Ohm's law I=U / R, adjusting the resistance of the potentiometer can change the magnitude of the output current (leakage current detection signal).

[0120] For example, if the upper limit current output is required to be 30mA, open the PLC's O0.0 port to make the first relay KA1 (the upper limit current conducting relay KA1) energize, and adjust the resistance of the upper limit current R1 potentiometer (current limiting resistor R1) to 300Ω (R=9V / 30mA=300Ω). When the leakage current detection signal is 30mA, the adjustment can be stopped.

[0121] Based on any of the aforementioned schemes, in one possible implementation, the test current signal output unit further includes an ammeter connected in series in the first circuit; the ammeter is used to display the value of the current in the first circuit.

[0122] In this solution, the ammeter displays the current value in the first circuit in real time. During testing, the resistance of the current-limiting resistor is adjusted according to the testing requirements, and the current in the first circuit changes accordingly. The ammeter allows operators to obtain the current value intuitively and promptly. For example, when adjusting the current-limiting resistor to change the leakage current detection signal, the ammeter can be used to observe the current change, thereby accurately controlling the output current.

[0123] For example, if the upper limit current of 30mA needs to be output, open the PLC's O0.0 port to make the upper limit current relay KA1 conduct and engage, adjust the resistance value of the upper limit current potentiometer R1, and confirm whether the current value has reached the upper limit current of 30mA by observing the ammeter reading.

[0124] refer to Figure 2 When multiple current signal output branches are set up, the ammeter can be connected in series in the common branch of the multiple current signal output branches.

[0125] Based on any of the aforementioned schemes, in one possible implementation, the test voltage signal output unit includes at least one voltage signal output branch.

[0126] The voltage signal output branch includes a voltage regulating motor, a voltage regulator, a second relay, a third relay, and a voltage regulating controller.

[0127] The voltage regulation signal output terminal of the voltage regulator controller is electrically connected to the voltage regulating motor, and the voltage regulation signal output terminal is used to output the voltage regulation signal.

[0128] The voltage regulating motor is connected to the voltage regulator, and the voltage regulating motor is used to adjust the output voltage of the voltage regulator according to the voltage regulation signal.

[0129] The first winding of the voltage regulator is electrically connected to the power supply, and the second winding of the voltage regulator is connected to the voltage output terminal through the normally open contact of the second relay.

[0130] The voltage output terminal is used to connect to the leakage current detection voltage output terminal, which is used to output the leakage current detection voltage signal.

[0131] The coil of the second relay and the normally open contact of the third relay form a second circuit, and the first control terminal of the voltage regulator is electrically connected to the coil of the third relay.

[0132] In this scheme, the voltage regulating motor is used to receive the voltage regulation signal from the voltage regulator controller and adjust the output voltage of the voltage regulator according to the signal content. The voltage regulating motor can change the internal structural parameters of the voltage regulator (such as the coil turns ratio) through mechanical transmission or other means, thereby realizing the regulation of the output voltage.

[0133] In this design, the voltage regulator, as the core component for generating the test voltage, has its first winding connected to a power source to obtain electrical energy. Through internal electromagnetic conversion, a voltage output is generated at the second winding. The magnitude of the output voltage is adjusted by a voltage-regulating motor.

[0134] In this design, the normally open contact of the second relay is connected in series between the second winding terminal and the voltage output terminal of the voltage regulator. When the coil of the second relay is energized, the normally open contact closes, transmitting the output voltage of the voltage regulator to the voltage output terminal; when the coil is de-energized, the normally open contact opens, cutting off the voltage output.

[0135] In this design, the normally open contact of the third relay is connected in series in the coil circuit of the second relay. The coil of the third relay is controlled by the first control terminal of the voltage regulator. When the first control terminal outputs a control signal to energize the coil of the third relay, the normally open contact of the third relay closes, thereby energizing the coil of the second relay; conversely, the coil of the second relay is de-energized.

[0136] In this scheme, the voltage regulator output terminal outputs a voltage regulation signal to the voltage regulator motor to control the output voltage of the voltage regulator; the first control terminal indirectly controls the action of the second relay by controlling the coil of the third relay, thereby realizing the on / off control of the voltage output terminal.

[0137] For example, in this solution, the voltage regulator controller outputs a voltage regulation signal to the voltage regulator motor through the voltage regulation signal output terminal according to the test requirements. After receiving the signal, the voltage regulator motor adjusts the internal parameters of the voltage regulator so that the voltage regulator outputs a voltage that meets the test requirements.

[0138] When leakage current detection requires output voltage, the first control terminal of the voltage regulator outputs a control signal to the coil of the third relay, energizing the coil of the third relay. The normally open contact of the third relay closes, the second circuit is connected, the coil of the second relay is energized, and its normally open contact closes.

[0139] At this time, the voltage at the second winding terminal of the voltage regulator is transmitted to the voltage output terminal through the normally open contact of the closed second relay, and then, after being connected to the leakage current detection voltage output terminal, the leakage current detection voltage signal is finally output.

[0140] When the test is over or the output voltage is no longer needed, the first control terminal of the voltage regulator stops outputting control signals to the coil of the third relay. The coil of the third relay is de-energized, and its normally open contact opens. The coil of the second relay is also de-energized, and its normally open contact opens, cutting off the voltage output.

[0141] Figure 3 This is a schematic diagram of the test voltage signal output unit structure in the embodiment, for reference. Figure 3 Based on any of the aforementioned schemes, in one possible implementation, the test voltage signal output unit includes two voltage signal output branches.

[0142] The AC power supply is electrically connected to the first winding of the voltage regulator T2 via the leakage current switch K1. The second winding of the voltage regulator T2 is connected to the voltage output terminals (LOUT, NOUT) via the normally open contact of the (first) second relay KA4.

[0143] The voltage regulator signal output terminal (AT1, NT1) of the voltage regulator controller (voltage regulator board Q1) is electrically connected to the first voltage regulator motor. The voltage regulation signal output terminal is used to output the voltage regulation signal. The first voltage regulator motor is connected to the voltage regulator T2.

[0144] The left limit +, left limit -, right limit +, and right limit - of the first station of the voltage regulator controller are connected to the corresponding signal terminals of the (first) voltage regulator motor.

[0145] The coil of the second relay KA4 and the normally open contact of the (first) third relay KA6 form a circuit, and the first control terminal of the voltage regulator is electrically connected to the coil of the third relay KA6.

[0146] The voltage regulator controller, the (first) voltage regulating motor, the voltage regulator T2, the second relay KA4, and the third relay KA6 constitute a voltage signal output branch.

[0147] The AC power supply is electrically connected to the first winding of the voltage regulator T3 via the leakage current switch K1. The second winding of the voltage regulator T3 is connected to the voltage output terminals (LOUT, NOUT) via the normally open contact of the second relay KA5.

[0148] The voltage regulator controller (voltage regulator board Q1) has two voltage regulator signal output terminals (AT2, NT2) that are electrically connected to the second voltage regulator motor. The voltage regulator signal output terminal is used to output the voltage regulation signal. The second voltage regulator motor is connected to the voltage regulator T3.

[0149] The left limit +, left limit -, right limit +, and right limit - of the two positions of the voltage regulator controller are connected to the corresponding signal terminals of the (second) voltage regulator motor.

[0150] The coil of the second relay KA5 and the normally open contact of the (second) third relay KA7 form a circuit, and the first control terminal of the voltage regulator is electrically connected to the coil of the third relay KA7.

[0151] The voltage regulator controller, the (second) voltage regulating motor, the voltage regulator T3, the second relay KA5, and the third relay KA7 constitute a voltage signal output branch.

[0152] For example, in this solution, if the voltage-regulating motor continues to rotate in one direction during the voltage regulation process, it may exceed the effective adjustment range of the voltage regulator, resulting in damage to the mechanical structure or abnormal performance of the voltage regulator.

[0153] The left and right limit signals essentially define the activity boundaries for the voltage regulating motor. When the voltage regulating motor drives the voltage regulator to adjust the voltage, and the voltage regulator approaches the left boundary of its adjustment range, the left limit signal is triggered, which provides feedback to the control system, prompting the voltage regulating motor not to adjust further to the left, thus avoiding damage caused by over-adjustment of the voltage regulator; similarly, the right limit signal can prevent the voltage regulator from over-adjusting to the right.

[0154] In this scheme, the left and right limit signals can ensure that the voltage regulator adjusts the voltage within a reasonable range, maintains a stable and controllable output voltage, and allows the lower limit voltage regulator (T2) and the upper limit voltage regulator (T3) to provide a suitable transformed voltage.

[0155] For example, in this solution, the second relays KA4 and KA5 can be AC ​​relays, and the third relays KA6 and KA7 can be DC relays.

[0156] In this scheme, the outputs of the lower limit voltage regulator (T2) and the upper limit voltage regulator (T3) after transformation are connected to the normally open terminals of the low-voltage start (KA4) AC contactor and the high-voltage start (KA5) AC contactor, respectively.

[0157] The voltage regulator controls the on / off state of the low-voltage on (KA6) and high-voltage on (KA7) relays, thereby controlling the on / off state of the corresponding AC contactors.

[0158] For example, if a lower limit voltage output of AC50V is required, the voltage regulator controller receives a signal and controls the voltage regulating motor of the lower limit voltage regulator (T2) to start rotating. When the voltage regulator controller reads that the current voltage has reached AC50V, it stops the power supply to the voltage regulating motor.

[0159] The voltage regulator opens port O0.3, causing the low-voltage conduction (KA6) relay to engage, which in turn engages the low-voltage start (KA4) AC contactor, resulting in AC 50V output to the voltage output terminals LOUT and NOUT.

[0160] refer to Figure 3 Based on any of the aforementioned schemes, in one possible implementation, the test voltage signal output unit further includes a commutation switch KA8.

[0161] The reversing switch KA8 is located at the voltage output terminal, and the second control terminal of the voltage regulator is electrically connected to the reversing switch KA8; the reversing switch is used to switch the voltage output terminal to output the first voltage or the second voltage.

[0162] For example, in this solution, the normally closed contacts of the reversing switch KA8 are connected to the voltage output terminals LOUT and NOUT respectively, and the normally open contacts of the reversing switch KA8 are connected to the voltage output terminals NOUT and LOUT respectively.

[0163] The LOUT and NOUT terminals of the voltage output can be switched by turning the commutator KA8 on or off.

[0164] Figure 4 This is a schematic diagram of the test result output unit structure in the embodiment, for reference. Figure 4 Based on any of the aforementioned schemes, the test result output unit includes the fourth relay KA9, the fifth relay KA10, the sixth relay KA13, and the seventh relay KA14.

[0165] The fourth relay KA9 and the fifth relay KA10 form a power-on self-locking structure. When the fourth relay KA9 is powered on, the fifth relay KA10 is self-locked. When the fifth relay KA10 is self-locked, the voltage output terminals LOUT and NOUT are continuously conducting.

[0166] The sixth relay KA13 and the seventh relay KA14 form a tripping structure, and the two ends X1 and X2 of the leakage current protection signal input terminal are connected in series with the coil of the sixth relay KA13.

[0167] The leakage current protection signal input terminals X1 and X2 are used to receive leakage current protection signals. The sixth relay KA13 is configured to power on when the PCBA outputs a leakage current protection signal.

[0168] When the sixth relay KA13 is energized, the fifth relay KA10 is de-energized, and the seventh relay KA14 is self-locked. When the seventh relay KA14 is self-locked, the test result output unit continuously outputs the test result signal.

[0169] For example, in this solution, the coil of the fourth relay KA9 is electrically connected to the controller. When the controller outputs from port O0.7, the power-on relay (KA9) is activated, which drives the power-on self-locking relay (KA10) to activate and continuously self-lock, so that LOUT and NOUT are continuously output to the downstream.

[0170] When the PCBA detects leakage current, it outputs a large current signal at terminals X1 and X2. This large current signal is applied to the coil of the trip relay (KA13), which drives the relay to engage, causing the coil of the power-on latching relay (KA10) to lose power, and interrupting the output of LOUT and NOUT to the PCBA.

[0171] At the same time, the two ends of the trip self-locking (KA14) relay coil are energized and continuously self-locked. At this time, the I0.2 port outputs a test result signal to inform the PCBA product at this station that the tripping action has been completed.

[0172] refer to Figure 4 In one possible implementation, the voltage output terminal includes a first output terminal LOUT and a second output terminal NOUT, and the leakage current detection voltage output terminal includes a third output terminal A1, a fourth output terminal B1, and a fifth output terminal C1.

[0173] The first output terminal LOUT is electrically connected to the third output terminal A1, and the second output terminal NOUT is electrically connected to the fourth output terminal B1 or the fifth output terminal C1.

[0174] The test result output unit also includes a switch KA12, which is used to electrically connect the second output terminal NOUT to the fourth output terminal B1, or to the fifth output terminal C1.

[0175] In this scheme, the coil of the switch KA12 is electrically connected to the controller. The normally closed contact of the switch KA12 is connected in series with the fourth output terminal B1, and the normally open contact is connected in series with the fifth output terminal C1. The switch KA12 can switch the NOUT output to B1 or C1, so that the PCBA receives the A1 / B1 or A1 / C1 voltage, realizing the commutation test function.

[0176] refer to Figure 4 In one possible implementation, the test result output unit further includes a shunt resistor and an eighth relay KA11.

[0177] One end X2 of the leakage current protection signal input terminal is also connected in series with the normally closed contact of the eighth relay KA11 and the normally closed contact switchable, and the normally open contact of the eighth relay KA11 is also connected in series with the shunt resistor.

[0178] In this solution, the PCBA test involves alternating between AC380V and AC220V voltages. When only one trip relay (KA13) is configured, performing the AC380V test step will result in excessive voltage being applied across the trip relay coil, reducing the coil's lifespan.

[0179] A resistor protection (KA11) relay is added across X2. When an AC380V test is performed, the relay will be turned on in a controlled manner, so that X2 flows through the circuit with the voltage divider resistor. When it reaches the coil of the trip relay (KA13), the voltage is within the normal range, protecting the long-term operation of the trip relay.

[0180] Based on any of the aforementioned schemes, in one possible implementation scheme, the output voltage of the third output terminal A1 and the fourth output terminal B1 includes a voltage of 220V, and the output voltage of the third output terminal A1 and the fifth output terminal C1 includes a voltage of 380V.

[0181] Based on any of the aforementioned solutions, in one possible implementation, the test equipment further includes a touch screen and a controller.

[0182] The touch screen is electrically connected to the controller, and the controller is connected to the test current signal output unit, the test voltage signal output unit, and the test result signal output unit.

[0183] The touchscreen is used to communicate and interact with the controller.

[0184] The controller is used to control and adjust the value of the leakage current detection current signal, adjust the value of the leakage current detection voltage signal, and receive test result signals.

[0185] In this solution, the touchscreen serves as the human-machine interface, providing an intuitive operation entry point. Operators can send commands to the controller and set test parameters (such as target values ​​for leakage current detection current and voltage signals) through touch operations, such as clicking and swiping.

[0186] The controller is connected to the test current signal output unit and the test voltage signal output unit. Based on instructions from the touchscreen, it precisely controls the adjustment of the current-limiting resistor in the test current signal output unit (e.g., by controlling a motor to adjust the resistance value), thereby adjusting the leakage current detection current signal value. Simultaneously, it controls the operation of the voltage regulating motor in the test voltage signal output unit, adjusting the voltage regulator output and changing the leakage current detection voltage signal value to meet different PCBA testing requirements.

[0187] The controller receives the test result signal from the test result signal output unit. Based on the received signal, it determines whether the PCBA has passed the leakage current test, and can further feed the result back to the touch screen display, or perform subsequent processing such as data storage and analysis.

[0188] refer to Figures 2 to 4 Based on any of the aforementioned schemes, the test circuit includes a test current signal output unit, a test voltage signal output unit, and a test result signal output unit.

[0189] The test current signal output unit includes a first transformer T1 (9V transformer), a first current signal output branch, a second current signal output branch, and a third current signal output branch.

[0190] The power supply AC is electrically connected to the first winding terminal of the first transformer T1 through the leakage current switch K1.

[0191] (First) The current-limiting resistor R1 is connected in series with the normally open contact of the (first) first relay KA1, and forms a first circuit with the second winding terminal of the first transformer T1. The wires of the first circuit pass through the magnetic ring (not shown in the figure).

[0192] (Second) The current-limiting resistor R2 is connected in series with the normally open contact of the (second) first relay KA2, and forms a second circuit with the second winding terminal of the first transformer T1. The wires of the second circuit pass through the magnetic ring.

[0193] (Third) The current-limiting resistor R3 is connected in series with the normally open contact of the (third) first relay KA3, and together with the second winding terminal of the first transformer T1, they form a third circuit. The wires of the third circuit pass through the magnetic ring.

[0194] The test current signal output unit also includes an ammeter, which is connected in series in the first, second, and third circuits; the ammeter is used to display the current value in the first, second, or third circuit.

[0195] The AC power supply is electrically connected to the first winding of the voltage regulator T2 via the leakage current switch K1. The second winding of the voltage regulator T2 is connected to the voltage output terminals (LOUT, NOUT) via the normally open contact of the (first) second relay KA4.

[0196] The voltage regulator signal output terminal (AT1, NT1) of the voltage regulator controller (voltage regulator board Q1) is electrically connected to the first voltage regulator motor. The voltage regulation signal output terminal is used to output the voltage regulation signal. The first voltage regulator motor is connected to the voltage regulator T2.

[0197] The left limit +, left limit -, right limit +, and right limit - of the first station of the voltage regulator controller are connected to the corresponding signal terminals of the (first) voltage regulator motor.

[0198] The coil of the second relay KA4 and the normally open contact of the (first) third relay KA6 form a circuit, and the first control terminal of the voltage regulator is electrically connected to the coil of the third relay KA6.

[0199] The voltage regulator controller, the (first) voltage regulating motor, the voltage regulator T2, the second relay KA4, and the third relay KA6 constitute a voltage signal output branch.

[0200] The AC power supply is electrically connected to the first winding of the voltage regulator T3 via the leakage current switch K1. The second winding of the voltage regulator T3 is connected to the voltage output terminals (LOUT, NOUT) via the normally open contact of the second relay KA5.

[0201] The voltage regulator controller (voltage regulator board Q1) has two voltage regulator signal output terminals (AT2, NT2) that are electrically connected to the second voltage regulator motor. The voltage regulator signal output terminal is used to output the voltage regulation signal. The second voltage regulator motor is connected to the voltage regulator T3.

[0202] The left limit +, left limit -, right limit +, and right limit - of the two positions of the voltage regulator controller are connected to the corresponding signal terminals of the (second) voltage regulator motor.

[0203] The coil of the second relay KA5 and the normally open contact of the (second) third relay KA7 form a circuit, and the first control terminal of the voltage regulator is electrically connected to the coil of the third relay KA7.

[0204] The voltage regulator controller, the (second) voltage regulating motor, the voltage regulator T3, the second relay KA5, and the third relay KA7 constitute a voltage signal output branch.

[0205] The test voltage signal output unit also includes a reversing switch KA8. The reversing switch KA8 is located at the voltage output terminal, and the second control terminal of the voltage regulator is electrically connected to the reversing switch KA8; the reversing switch is used to switch the voltage output terminal to output a first voltage or a second voltage.

[0206] The test result output unit includes the fourth relay KA9, the fifth relay KA10, the sixth relay KA13, and the seventh relay KA14.

[0207] The fourth relay KA9 and the fifth relay KA10 form a power-on self-locking structure. When the fourth relay KA9 is powered on, the fifth relay KA10 is self-locked. When the fifth relay KA10 is self-locked, the voltage output terminals LOUT and NOUT are continuously conducting.

[0208] The sixth relay KA13 and the seventh relay KA14 form a tripping structure, and the two ends X1 and X2 of the leakage current protection signal input terminal are connected in series with the coil of the sixth relay KA13.

[0209] The leakage current protection signal input terminals X1 and X2 are used to receive leakage current protection signals. The sixth relay KA13 is configured to power on when the PCBA outputs a leakage current protection signal.

[0210] When the sixth relay KA13 is energized, the fifth relay KA10 is de-energized, and the seventh relay KA14 is self-locked. When the seventh relay KA14 is self-locked, the test result output unit continuously outputs the test result signal.

[0211] The voltage output terminals include the first output terminal LOUT and the second output terminal NOUT. The leakage current detection voltage output terminals include the third output terminal A1, the fourth output terminal B1, and the fifth output terminal C1.

[0212] The first output terminal LOUT is electrically connected to the third output terminal A1, and the second output terminal NOUT is electrically connected to the fourth output terminal B1 or the fifth output terminal C1.

[0213] The test result output unit also includes a switch KA12, which is used to electrically connect the second output terminal NOUT to the fourth output terminal B1, or to the fifth output terminal C1.

[0214] The test result output unit also includes a shunt resistor and an eighth relay KA11.

[0215] One end X2 of the leakage current protection signal input terminal is also connected in series with the normally closed contact of the eighth relay KA11 and the normally closed contact switchable, and the normally open contact of the eighth relay KA11 is also connected in series with the shunt resistor.

[0216] refer to Figure 4 One set can be set in the detection circuit. Figure 4 The test result output unit shown, based on the trip structure and the corresponding leakage current protection signal input terminal, can realize single-station product testing.

[0217] For example, when performing single-station testing on a 16-flat product, the test result output unit flows sequentially under the control of the controller, requiring 16 testing cycles to complete the test.

[0218] refer to Figure 4 For example, in this solution, multiple sets of [equipment / systems] can be set in the detection circuit. Figure 4 The test result output unit shown can simultaneously test the product functions of multiple workstations based on multiple tripping structures and corresponding leakage current protection signal input terminals.

[0219] For example, when performing four-station testing on a 16-panel product, the four stations test simultaneously under the control of the controller. The test results are output sequentially from the unit, and the test requires four testing cycles to complete.

[0220] In this solution, the testing equipment may also include a rack. The rack integrates the testing mechanism, mechanical transmission equipment, data interaction equipment, I / O control equipment, and a slide rail platform. The slide rail platform houses a low-voltage electrical assembly.

[0221] In this scheme, the testing mechanism is assembled and connected to the mechanical transmission equipment; the data interaction equipment is connected to the IO control equipment; and the testing mechanism, mechanical transmission equipment, and IO control equipment are all connected to the low-voltage electrical unit.

[0222] For example, in this solution, the testing mechanism includes a pressure bed, pressure bar, carrier plate, needle bed, probe and needle sleeve, limit switch, magnetic ring clamp and electrical aviation socket.

[0223] The pressure bar is assembled onto the press according to customized requirements. The carrier plate is assembled onto the needle bed via guide rods, bearings, and spring posts. The probe and needle sleeve are assembled into the needle bed according to customized requirements, mating with the carrier plate.

[0224] The magnetic ring clamp is used to adapt to various magnetic rings (i.e., the magnetic ring in the test current signal output unit), connect probes and pin sleeves. The magnetic ring clamp has an IDC connector inside, which facilitates efficient replacement of magnetic rings.

[0225] The electrical aviation socket connects to the probe and pin sleeve to enable electrical signal interaction with the low-voltage electrical unit.

[0226] For example, in this solution, the mechanical transmission device includes a pressure reducing valve, a magnetic switch, a solenoid valve, and a dual-axis cylinder. The solenoid valve is connected in sequence to the pressure reducing valve and the dual-axis cylinder, and the magnetic switch is mounted on the dual-axis cylinder to detect the movement status of the dual-axis cylinder.

[0227] The I / O control devices are connected to magnetic switches and solenoid valves respectively to control the operation of the mechanical transmission equipment. In addition, a connecting plate is mounted on the press for connecting the mechanical transmission equipment.

[0228] In this solution, the low-voltage electrical unit includes a relay group (for switching and conversion circuits) and a button group (for start / stop operation) connected to the IO control device; protectors and industrial aviation sockets for the protection circuit; and potentiometer groups (such as current-limiting resistors R1 to R3 in the test current signal output unit) and relay groups (for control circuits) connected to the signal source.

[0229] For example, in this solution, the data interaction device can be a touch screen, which is used to control the test equipment (through the test current signal output unit and the test voltage signal output unit) to output the set leakage current detection current signal and leakage current detection voltage signal.

[0230] The low-voltage electrical unit controls the mechanical transmission equipment, which securely connects the leakage current detection PCBA to the testing mechanism.

[0231] The IO control device may include a PLC and IO boards. The IO control device detects whether the conditions for the test process are met and controls the low-voltage electrical unit to execute the test process.

[0232] At the same time, the IO control device communicates with the data interaction device and controls the switching of the low-voltage electrical group according to the program requirements, so that the leakage current detection current signal and leakage current detection voltage signal are transmitted to the leakage current detection type PCBA in the test mechanism.

[0233] The leakage current detection PCBA in the testing unit outputs a leakage current protection signal to the low-voltage electrical group (the relay specified in the test result output unit). The IO control device detects the result presented by the low-voltage electrical group (i.e., the test result signal generated when the relay specified in the test result output unit is activated) and transmits the result to the data interaction device, which then further transmits the result.

[0234] Example 2

[0235] This embodiment proposes a leakage current detection type PCBA test device, including any of the test circuits described in Embodiment 1. The test circuits, implementation methods, and beneficial effects are the same as the corresponding contents described in Embodiment 1, and the specific contents will not be repeated.

[0236] Based on any of the aforementioned solutions, in one possible implementation, the test equipment further includes a controller.

[0237] The controller is connected to the test current signal output unit, the test voltage signal output unit, and the test result signal output unit.

[0238] The controller is used to adjust the value of the leakage current detection current signal by controlling the test current signal output unit, adjust the value of the leakage current detection voltage signal by controlling the test voltage signal output unit, and receive the test result signal by controlling the test result signal output unit.

[0239] In this solution, the controller can be a PLC, which is connected to the test current signal output unit and can send precise control commands to it.

[0240] For example, when it is necessary to change the value of the leakage current detection signal, the PLC generates a corresponding control signal based on the preset test program or parameters input by the operator on an interactive interface such as a touch screen. This signal is transmitted to the current adjustment circuit in the test current signal output unit. For circuits based on potentiometer adjustment, the PLC can control the motor to drive the potentiometer to rotate, changing the resistance value connected to the circuit, thereby adjusting the current in the loop and achieving precise adjustment of the leakage current detection signal value.

[0241] The PLC is connected to the test voltage signal output unit to adjust the value of the leakage current detection voltage signal. The voltage regulation circuit in the test voltage signal output unit, such as a circuit based on a linear regulator and potentiometer or a circuit based on a switching power supply module and feedback control, receives control signals from the PLC.

[0242] Taking a circuit based on a linear regulator and a potentiometer as an example, the PLC controls the change in the resistance of the potentiometer to change the output voltage of the linear regulator, thereby adjusting the leakage current detection voltage signal.

[0243] When the PCBA completes the leakage current test and outputs the test result signal through the test result signal output unit, the PLC can quickly receive the signal.

[0244] Based on the test results, the PLC can control the alarm tri-color lights and start the corresponding sorting devices. The PLC can also store the test results data in its internal memory or upload it to the host computer for production data statistics and analysis, providing data support for production process improvement.

[0245] Based on any of the aforementioned solutions, in one possible implementation, the testing equipment further includes a touch screen, which is electrically connected to the controller. The touch screen is used to communicate and interact with the controller, input test commands, and display test results.

[0246] Input test commands are used to adjust the value of the leakage current detection current signal and the value of the leakage current detection voltage signal.

[0247] In this solution, operators can input test commands via a touchscreen to precisely adjust the values ​​of the leakage current detection current and voltage signals.

[0248] For example, when testing different PCBA models, specific current and voltage values ​​are input on the touchscreen according to their specifications. These instructions are quickly transmitted to the controller, which then controls the corresponding adjustment circuits of the test current signal output unit and the test voltage signal output unit to change the magnitude of the leakage current detection current and voltage signals to meet the testing requirements of different PCBAs.

[0249] refer to Figures 5 to 8 Based on any of the aforementioned solutions, in one possible implementation, the test equipment further includes a clamping linkage device for fixing the leakage current detection type PCBA to be tested.

[0250] For example, in this solution, the clamping linkage device may include: a dual-axis cylinder 202: serving as a power source to provide the power to push the pressure plate; a pressure plate: directly acting on the leakage current detection type PCBA to be tested, clamping and fixing it; a guide rod and linear bearing: used to ensure the linearity and stability of the pressure plate movement; a magnetic switch 203: installed on the dual-axis cylinder 202, used to detect the position of the piston of the dual-axis cylinder 202, thereby determining the position state of the pressure plate; and a solenoid valve 13: controlling the air intake and exhaust of the dual-axis cylinder 202 to realize the extension and retraction of the dual-axis cylinder 202.

[0251] In this solution, PLC 16 is connected to touch screen 3, solenoid valve 13, magnetic switch 203, etc., and controls the operation of the entire pressing linkage device according to the instructions input by the operator on the touch screen.

[0252] In this scheme, PLC 16 receives control commands from touch screen 3. The PLC is electrically connected to solenoid valve 13 and controls the opening and closing of solenoid valve 13 by outputting control signals.

[0253] Solenoid valve 13 is connected to dual-axis cylinder 202 via an air pipe to control the cylinder's air intake and exhaust. Magnetic switch 203 is mounted on dual-axis cylinder 202 and electrically connected to PLC 16, feeding back the cylinder piston position signal to PLC 16. Pressure plate is connected to the piston rod of dual-axis cylinder 202 via a connector, and guide rod passes through a linear bearing and is fixed to the pressure plate and the equipment frame.

[0254] For example, in this solution, when the operator inputs a clamping command on the touchscreen 3, the touchscreen 3 transmits the command to the PLC 16. Upon receiving the command, the PLC 16 controls the solenoid valve 13 to operate, causing the dual-axis cylinder 202 to receive air. The cylinder piston rod extends, pushing the pressure plate downwards to clamp the PCBA to be tested. The magnetic switch 203 monitors the position of the cylinder piston in real time and feeds the signal back to the PLC 16. When the pressure plate reaches the designated position (i.e., the PCBA is clamped), the magnetic switch 203 feeds the signal back to the PLC 16, and the PLC 16 stops sending control signals to the solenoid valve 13, maintaining the current state of the cylinder.

[0255] After the test is completed, the operator inputs the release command on the touch screen 3. The PLC 16 controls the solenoid valve 13 to act, causing the dual-axis cylinder 202 to exhaust, the cylinder piston rod to retract, the pressure plate to move upward, and the PCBA to be released.

[0256] For example, in this solution, the clamping linkage device may include: an electric push rod: providing power for linear motion to push the pressure block to move up and down; a pressure block: directly contacting the leakage current detection type PCBA to be tested and clamping it in place; a position sensor: mounted on the electric push rod to detect the position of the electric push rod, thereby determining the position status of the pressure block; and a motor driver: controlling the rotation of the electric push rod motor to realize the extension and retraction of the electric push rod.

[0257] In this solution, PLC 16 is connected to touch screen 3, motor driver, position sensor, etc., and controls the operation of the entire pressing linkage device according to the instructions input by the operator on touch screen 3.

[0258] For example, in this solution, PLC 16 receives control commands from touchscreen 3. Simultaneously, PLC 16 is electrically connected to a motor driver and controls the operation of the motor driver by outputting control signals. The motor driver is connected to the motor of the electric linear actuator and drives the motor to rotate. A position sensor is mounted on the electric linear actuator and electrically connected to PLC 16, feeding back the position signal of the electric linear actuator to PLC 16. A pressure block is mounted on the end of the electric linear actuator.

[0259] When the operator inputs a clamping command on touchscreen 3, touchscreen 3 transmits the command to PLC 16. Upon receiving the command, PLC 16 sends a control signal to the motor driver, which in turn drives the motor of the electric push rod to rotate, causing the push rod to extend and push the pressure block downwards, clamping the PCBA to be inspected. A position sensor continuously monitors the position of the electric push rod and feeds the signal back to PLC 16. When the pressure block reaches the designated position (i.e., the PCBA is clamped), the position sensor sends a signal back to PLC 16, and PLC 16 stops sending control signals to the motor driver, maintaining the current state of the electric push rod.

[0260] After the test is completed, the operator inputs the release command on the touch screen 3. The PLC 16 controls the motor driver to reverse the motor of the electric push rod, the push rod of the electric push rod retracts, the pressure block moves upward, and the PCBA is released.

[0261] Based on the aforementioned test equipment including a clamping device, in one possible implementation, the clamping linkage device includes: a pressure reducing valve 201, a solenoid valve 13, a dual-axis cylinder 202, a magnetic switch 203, a limit switch 210, a press 205, a pressure bar 206, and a carrier plate 207.

[0262] The press 205 is mechanically connected to the twin-shaft cylinder 202 via a connecting plate. The press 205 is used to provide the mounting points for the pressure bar 206.

[0263] The dual-axis cylinder 202 is connected to the solenoid valve 13 and the magnetic switch 203. The solenoid valve 13 is used for motion control of the dual-axis cylinder 202, and the magnetic switch 203 is used for monitoring the motion position of the dual-axis cylinder 202.

[0264] The pressure reducing valve 201 is connected to the dual-shaft cylinder 202 via the solenoid valve 13. The pressure reducing valve 201 is used to regulate the air pressure of the dual-shaft cylinder 202.

[0265] Limit switch 210 is used for monitoring the motion position of press 205.

[0266] In this solution, the main function of the pressure reducing valve 201 is to regulate the air pressure of the dual-axis cylinder 202. By precisely controlling the air pressure entering the dual-axis cylinder 202, it ensures that the dual-axis cylinder 202 outputs appropriate thrust, avoiding damage to the PCBA under test due to excessive air pressure, or insufficient clamping force due to insufficient air pressure, which would prevent the PCBA from being effectively fixed.

[0267] Solenoid valve 13 serves as the control element for the movement of the dual-axis cylinder 202. Based on the received control signal, it switches its on / off state to control the flow of compressed air, thereby enabling the extension and retraction of the dual-axis cylinder 202, which in turn drives the press 205 to move.

[0268] The dual-axis cylinder 202 is the core component that provides power. It converts the pressure energy of compressed air into mechanical energy, which, through the extension and retraction of the piston rod, drives the press 205, which is mechanically connected to it, to move up and down, providing the necessary pressure to press the PCBA to be tested.

[0269] The magnetic switch 203 is used to monitor the movement position of the dual-axis cylinder 202. It utilizes the principle of magnetic induction to detect the position of the piston in the dual-axis cylinder 202 and feeds the position signal back to the control system. This allows the system to accurately determine whether the dual-axis cylinder 202 has reached the predetermined position, enabling further control operations.

[0270] Limit switch 210 monitors the movement position of press 205. When press 205 moves to a specific position, limit switch 210 is activated, and the limit switch 210 feeds back the position signal to the control system. This helps to accurately control the movement range of press 205 and prevent excessive movement of press 205 from causing equipment damage or PCBA damage.

[0271] The press 205 provides mounting points for the pressure bar 206 and is mechanically connected to the dual-axis cylinder 202 via a connecting plate. Driven by the dual-axis cylinder 202, the press 205 moves up and down, allowing the pressure bar 206 mounted on it to apply pressure to the PCBA to be tested, thus achieving the function of clamping and fixing.

[0272] The pressure bar 206 acts directly on the PCBA to be tested, applying the pressure transmitted by the pressure press 205 to the PCBA to ensure that the PCBA remains stable during the test and avoids affecting the test results due to shaking or displacement.

[0273] The carrier board 207 is used to support the PCBA to be tested, providing a stable placement platform to ensure the positional accuracy of the PCBA during the clamping and testing process.

[0274] In this design, the outlet of the pressure reducing valve 201 is connected to the inlet of the solenoid valve 13 via a pipe, and the outlet of the solenoid valve 13 is then connected to the inlet of the dual-shaft cylinder 202 via a pipe. Thus, compressed air first passes through the pressure reducing valve 201 to regulate its pressure, and then enters the dual-shaft cylinder 202 under the control of the solenoid valve 13, driving its movement.

[0275] The press 205 is mechanically connected to the piston rod of the dual-axis cylinder 202 via a connecting plate. The telescopic movement of the dual-axis cylinder 202 can directly drive the press 205 to move up and down.

[0276] Magnetic switch 203 and limit switch 210 are electrically connected to PLC 16, feeding back the position signals they detect to the control system. Simultaneously, the control system is electrically connected to solenoid valve 13, sending control signals to it to control the movement of the dual-axis cylinder 202.

[0277] In this scheme, the operator issues a pressing command through the touch screen 3 or other control devices. After receiving the command, the control system sends a control signal to the solenoid valve 13, causing the solenoid valve 13 to switch to the air-venting state. The compressed air, after the pressure is regulated by the pressure reducing valve 201, enters the dual-axis cylinder 202, pushing the piston rod of the dual-axis cylinder 202 to extend, thereby driving the press 205 and the pressure bar 206 to move downward.

[0278] During the movement of the dual-axis cylinder 202, the magnetic switch 203 monitors its position in real time and feeds back the position signal to the control system. When the press 205 moves to a certain position, it triggers the limit switch 210, which feeds back a signal to the control system, indicating that the press 205 has reached the predetermined position. At this time, the control system stops sending the air supply signal to the solenoid valve 13, the dual-axis cylinder 202 stops moving, and the pressure bar 206 applies stable pressure to the PCBA to be tested, pressing and fixing it.

[0279] After the test is completed, the operator issues a release command via touchscreen 3 or other control device. Upon receiving the command, the control system sends a control signal to solenoid valve 13, causing it to switch to the exhaust state. Compressed air in the dual-axis cylinder 202 is discharged, and the piston rod retracts under the action of a spring or other reset device, driving the press 205 and pressure bar 206 upward, releasing the PCBA. Magnetic switch 203 and limit switch 210 continue to monitor the position of the dual-axis cylinder 202 and press 205. When they return to their initial positions, position signals are fed back to the control system, completing one full test cycle.

[0280] Based on any of the aforementioned solutions, in one possible implementation, the test equipment further includes a probe device for injecting a leakage current detection signal into the leakage current detection type PCBA to be tested. The leakage current detection signal includes a leakage current detection current signal and / or a leakage current detection voltage signal.

[0281] For example, in this solution, the probe device may include a probe 209, a probe holder, an adapter plate, and a mounting bracket. The probe 209 directly contacts the test point on the leakage current detection PCBA to be tested, transmitting the leakage current detection signal to the circuitry inside the PCBA.

[0282] The mounting bracket is used to install the probe holder. One end of the probe 209 is connected to the probe holder or adapter board by soldering, crimping or other electrical connection methods, while the other end is in direct contact with the test point on the PCBA during testing.

[0283] Based on the aforementioned scheme including a probe device, in one possible implementation, the probe device includes: a needle bed 208 and a probe 209, wherein the probe 209 is equipped with a needle sheath.

[0284] The needle bed 208 is mechanically connected to the carrier board 207, and the probe 209 is mounted on the needle bed. The probe 209 is used to inject a leakage current detection signal into the leakage current detection type PCBA to be tested.

[0285] In this design, the needle bed 208 is used to fix and support the probe 209, ensuring the positional accuracy and stability of the probe 209 during the detection process.

[0286] Specifically, the bed of needles 208 serves as the mounting base for the probes 209, enabling multiple probes 209 to be arranged in a specific layout and spacing to accurately correspond to the test points on the leakage current detection PCBA under test. Simultaneously, the bed of needles 208 may also possess certain electrical connection functions, such as connecting each probe 209 to the signal output unit of the testing equipment to achieve the transmission of leakage current detection signals.

[0287] In this solution, the needle bed 208 is connected to the carrier plate 207 by a mechanical connection. Specifically, the needle bed 208 and the carrier plate 207 are assembled by springs, positioning pins and linear bearings. The carrier plate 207 is set above the needle bed 208 and can move up and down. When the pressure bar 206 presses the PCBA down, it will drive the carrier plate 207 to move down until the PCBA can contact the probe 209.

[0288] In addition, the needle bed 208 is electrically connected to other parts of the test equipment (such as the test current signal output unit and the test voltage signal output unit) via wires or printed circuit board (PCB) lines to enable signal transmission.

[0289] In this design, the needle sleeve covers the outside of the probe 209, preventing mechanical damage and corrosion from external sources and extending its service life. During testing, the needle sleeve also provides positioning and guidance, ensuring that the probe 209 accurately contacts the test point on the PCBA, reducing test errors caused by probe 209 misalignment or movement. Furthermore, the needle sleeve provides insulation, preventing short circuits between the probe 209 and surrounding metal components or other conductors, thus ensuring the accuracy and stability of the test signal.

[0290] Based on any of the aforementioned solutions, in one possible implementation, the test equipment further includes a power supply device for supplying power to the electrical components in the test equipment.

[0291] In this solution, the power supply unit may include an input circuit, which may include a power plug, a fuse, etc. The power plug is used to connect to an external AC power source to introduce power to the test equipment. The function of the fuse is to promptly disconnect the circuit in the event of an overload or short circuit, protecting the equipment from damage.

[0292] The power supply unit can also be configured with power conversion circuits, which may include rectifiers, filters, and voltage regulators. The rectifier converts the input AC power into DC power; the filter further smooths the rectified DC voltage, reducing voltage ripple and providing a stable DC power supply for subsequent circuits. The voltage regulator automatically adjusts the output voltage according to load changes, ensuring output voltage stability and enabling all electrical components in the test equipment to operate under stable voltage, preventing voltage fluctuations from affecting equipment performance or causing component damage.

[0293] The power supply unit may also include an output circuit with multiple output ports, each capable of outputting DC power at different voltage and current levels according to the needs of different electrical components. Additionally, the output circuit may be equipped with overcurrent protection, overvoltage protection, and other circuits to prevent damage to the power supply unit or other electrical components due to abnormal loads.

[0294] In this design, the input circuit of the power supply unit is connected to an external AC power source via a power plug. The components in the input circuit are connected in series: the AC power first passes through the power plug, then connects to the fuse, then passes through the EMI filter, and finally outputs to the power conversion circuit.

[0295] The input terminal of the power conversion circuit is connected to the output terminal of the input circuit, and its output terminal is connected to the output circuit. Inside the power conversion circuit, components such as rectifiers, filters, and voltage regulators are usually connected in series to achieve gradual conversion and stabilization of the power supply.

[0296] Each output port of the output circuit is connected to different electrical components in the test equipment, such as the controller, touch screen 3, probe device, solenoid valve 13 in the clamping linkage device, and dual-axis cylinder 202, to provide the required power to these components.

[0297] Based on the aforementioned scheme including a power supply device, in one possible implementation, the power supply device includes: an industrial aviation socket 5, a switching power supply 18, and a leakage current protector 10.

[0298] The industrial aviation socket 5 is electrically connected to the switching power supply 18 via the leakage current protector 10; the industrial aviation socket 5 is used to connect to the mains power; the switching power supply 18 is used to supply power to the electrical components; the leakage current protector 10 is used to provide leakage protection for the power supply circuit where the switching power supply 18 is located.

[0299] In this solution, the industrial aviation socket 5 serves as the interface for connecting the power supply unit to the external mains power, ensuring that the mains power can be stably and safely connected to the power supply unit during the operation of the test equipment, thus providing a foundation for subsequent circuit conversion and equipment power supply.

[0300] The leakage current protector 10 is used to ensure the safety of the power supply circuit. When leakage is detected in the power supply circuit, that is, when the outflow current is not equal to the inflow current and the difference exceeds the set threshold, the leakage current protector 10 will quickly act to cut off the circuit, thereby preventing electric shock accidents caused by leakage and damage to the equipment, and providing reliable protection for the power safety of the switching power supply 18 and the entire test equipment.

[0301] The main function of the switching power supply 18 is to efficiently convert and regulate the input AC power, outputting a stable DC voltage that meets the requirements of various electrical components in the testing equipment. It can flexibly adjust the output parameters according to the voltage and current requirements of different electrical components, providing stable and reliable power to the controller, touchscreen 3, and actuators in the testing mechanism, ensuring the normal operation of these components. It is the core component that provides the power source for the stable operation of the testing equipment.

[0302] In this design, the input terminal of the leakage current protector 10 is connected to the aviation socket to receive mains power from the industrial aviation socket 5; its output terminal is connected to the input terminal of the switching power supply to transmit the current after leakage detection to the switching power supply 18. In the power supply circuit of the entire power supply device, the leakage current protector 10 is located between the aviation socket and the switching power supply 18, playing an important role in intermediate protection and current transmission control.

[0303] In this scheme, the output terminal of the switching power supply 18 is connected to each electrical component in the test equipment through multiple lines, transmitting the converted and regulated DC power to them.

[0304] Based on any of the aforementioned solutions, in one possible implementation, the test equipment further includes: a frame 1 and a slide rail drawer 17, the slide rail drawer 17 being slidably connected to the frame 1, and the slide rail drawer 17 being used to place intermediate relays and AC contactors in the test circuit.

[0305] The controller is electrically connected to the intermediate relay, and the controller controls the operation of the AC contactor through the intermediate relay.

[0306] In this design, the frame 1 serves as the basic support structure for the testing equipment, providing a stable physical framework for the entire device. It supports all components of the equipment, including the testing mechanism, power supply, and slide drawer 17.

[0307] The slide-rail drawer 17 is mainly used to store and protect intermediate relays and AC contactors in test circuits. The slide-rail design allows the drawer to be easily pulled out and pushed into the rack, greatly facilitating equipment maintenance, repair, and component replacement.

[0308] The slide drawer 17 is slidably connected to the frame 1 via slide rails, ensuring that the slide drawer 17 can smoothly enter and exit within the frame 1. Meanwhile, the intermediate relays and AC contactors housed inside the slide drawer 17 are connected to the controller and other circuit components of the testing equipment via electrical wiring, enabling control of the testing circuits and signal transmission.

[0309] In this design, the intermediate relay serves to amplify and isolate the signal between the controller and the AC contactor. Since the control signal output by the controller may have a small current that cannot directly drive the AC contactor, the intermediate relay, upon receiving the control signal from the controller, amplifies the small control current into a larger contact current through its internal electromagnetic mechanism, thereby reliably controlling the on / off state of the AC contactor coil.

[0310] AC contactors are mainly used to control the on / off state of the main circuit in a test circuit. The main contacts of an AC contactor are usually connected in series in the main circuit of the test circuit. When the intermediate relay controls the coil of the AC contactor to be energized, the electromagnetic mechanism inside the AC contactor is activated, causing the main contacts to close, connecting the main circuit, allowing a large current to pass through, and providing power to the actuators of the test equipment (such as the motor in the test mechanism). When the coil is de-energized, the main contacts open, cutting off the main circuit and stopping the operation of the equipment.

[0311] In this design, the input terminal of the intermediate relay is electrically connected to the controller to receive control signals from the controller; the output terminal of the intermediate relay is electrically connected to the coil of the AC contactor, controlling the energization and de-energization of the AC contactor coil through the closing and opening of its contacts. Simultaneously, the intermediate relay is also connected to other parts of the test circuit (such as the power supply circuit) to obtain the power required for operation.

[0312] In this scheme, the coil of the AC contactor is electrically connected to the output terminal of the intermediate relay to receive the control signal from the intermediate relay; the main contacts of the AC contactor are connected in series in the main circuit of the test circuit and connected to the electrical load of the test equipment (such as the motor in the test mechanism) and the power supply device to realize the on-off control of the main circuit, thereby controlling the operating status of the entire test equipment.

[0313] Based on the aforementioned test equipment including rack 1, in one possible implementation, the test equipment further includes: a safety light curtain 12, which is disposed on rack 1.

[0314] The controller is connected to the safety light curtain 12 and is configured to stop the leakage current test based on the safety detection signal of the safety light curtain 12; if a person or object enters the leakage current test area, the safety light curtain 12 generates a safety detection signal.

[0315] In this design, the safety light curtain 12 may include a transmitter and a receiver. The transmitter includes multiple infrared light-emitting diodes (LEDs) arranged in a specific pattern to form a light source array. Its function is to emit infrared light to the receiver, forming infrared beams.

[0316] The receiver corresponds to the transmitter and includes a photoelectric sensor for receiving infrared light emitted by the transmitter. When an object blocks any beam of light between the transmitter and receiver, the corresponding photoelectric sensor at the receiver detects the change in light and converts this change into an electrical signal.

[0317] The safety light curtain 12 is installed on the rack 1, and its specific position is usually around the perimeter of the leakage current test area to ensure that the test area is fully covered and to prevent people or objects from accidentally entering during the test and causing safety accidents.

[0318] The receiver of the safety light curtain 12 is connected to the controller via a cable. When the safety light curtain 12 detects an object blocking the light, indicating that a person or object has entered the leakage current test area, the receiver transmits the generated electrical signal as a safety detection signal to the controller via the cable. Upon receiving this signal, the controller will stop the leakage current test according to a preset program to ensure the safety of personnel and equipment.

[0319] Based on any of the aforementioned schemes, in one possible implementation, the controller is further equipped with an emergency stop switch 6, an enable button 7, and a metal button 11.

[0320] Emergency stop switch 6 is used for manual control to cut off the power supply of leakage current detection PCBA test equipment; enable button 7 is used to enable leakage current detection PCBA test equipment; metal button 11 is used to start leakage current test.

[0321] Figure 5 This is a schematic diagram of the front structure of the test equipment in the embodiment. Figure 6 This is a partial structural diagram of the operating area of ​​the test equipment in the embodiment. Figure 7 This is a schematic diagram of the front structure of the test equipment in the embodiment. Figure 8 This is a schematic diagram of a partial internal structure of the test equipment in the embodiment.

[0322] refer to Figures 5-8 Based on any of the aforementioned solutions, in one possible implementation, the testing equipment may include:

[0323] 1. Frame; 2. Testing mechanism; 3. Touch screen; 4. Alarm tri-color light; 5. Industrial aviation socket; 6. Emergency stop switch; 7. Enable button; 8. Adjustment knob; 9. Digital ammeter; 10. Residual current device; 11. Metal button; 12. Safety light curtain; 13. Solenoid valve; 14. Intermediate relay group; 15. AC contactor group; 16. PLC; 17. Slide rail drawer; 18. Switching power supply; 19. Electric voltage regulator module.

[0324] The testing mechanism 2 and its supporting components include a pressure reducing valve 201, a dual-axis cylinder 202, a magnetic switch 203, a connecting plate 204, a pressure bed 205, a pressure bar 206, a carrier plate 207, a needle bed 208, a probe (and needle sleeve) 209, a limit switch 210, an electrical aviation socket 211, and a magnetic ring clamp 212. All components of the testing mechanism 2 are assembled into the frame 1.

[0325] Intermediate relay group 14, AC contactor group 15, and PLC 16 are assembled into slide rail drawer 17.

[0326] In this solution, the industrial aviation socket 5 provides power to the test equipment and is electrically connected to the leakage current protector 10.

[0327] The residual current device 10 provides leakage protection for the electrical circuit and is electrically connected to the switching power supply 18 and the electric voltage regulator module 19.

[0328] The switching power supply 18 is electrically connected to the digital ammeter 9, the touch screen 3 and the PLC 16 respectively.

[0329] refer to Figure 3 The electric voltage regulator module 19 includes voltage regulators (T2, T3) that provide leakage current detection voltage signals, a voltage regulating motor, and a voltage regulating controller (Q1) that controls the operation of the voltage regulating motor. The voltage regulators are connected to the AC contactor group 15 (including KA4, KA5), and the voltage regulating controller is electrically connected to the touch screen 3.

[0330] refer to Figure 3The AC contactor group 15 is responsible for switching and controlling the low-voltage starting circuit and the high-voltage starting circuit.

[0331] refer to Figure 2 The electric voltage regulator module 19 also includes potentiometers (R1 to R3) that provide leakage current detection current signals. The potentiometers are electrically connected to the adjustment knob 8, which is used to adjust the leakage current detection current signal. The potentiometers are also electrically connected to the digital ammeter 9, which is used to measure the leakage current detection current signal parameters.

[0332] PLC 16 is electrically connected to solenoid valve 13, which is used to control the pneumatic operation of test mechanism 2; test mechanism 2 is used for the installation and connection of the leakage current detection type PCBA to be tested.

[0333] The testing unit 2 is also electrically connected to the intermediate relay group 14 (including KA1, KA2, KA3, KA6, KA7, KA8, KA12, KA9, KA13, etc.); the intermediate relay group 14 is used for switching, detecting and controlling electrical signals.

[0334] In this solution, the three-color alarm light 4 is used to indicate the status and test results of the test equipment. The emergency stop switch 6 is used to cut off the power supply to the test equipment in an emergency. The enable button 7 is used to enable the test equipment. The metal button 11 is used to start the test process. The safety light curtain 12 is used for safety protection.

[0335] In this design, the pressure reducing valve 201 is mounted on the side wing plate of the test mechanism 2 to regulate the air pressure and is connected to the external air source and the air circuit of the solenoid valve 13.

[0336] The dual-axis cylinder 202 is mounted on the front panel of the test mechanism 2 for energy transmission. It is connected to the air circuit of the solenoid valve 13 and assembled with the magnetic switch 203 and the connecting plate 204.

[0337] Magnetic switch 203 and limit switch 210 are respectively mounted on the side wing plate of test mechanism 2 and the side wing slot of dual-axis cylinder 202 for motion status monitoring, and are respectively electrically connected to PLC 16.

[0338] The needle bed 208 is limited and mounted on the support plate of the test mechanism 2. The structure can be quickly replaced and is used to set the mounting points of the matching probes (and needle sleeves) 209 to meet the requirements of leakage current detection PCBA. The needle bed 208 is assembled with the probes (and needle sleeves) 209, assembled with the carrier plate 207 through spring pillars, plug screws, positioning pillars and linear bearings, assembled with the magnetic ring clamp 212 through magnetic attraction or limiting grooves, and assembled with the electrical aviation socket 211.

[0339] The probe (and pin sleeve) 209 is used for contact leakage current detection type PCBA and signal transmission.

[0340] The carrier board 207 is provided with a recessed groove for reliable support of the leakage current detection PCBA, and a positioning pin is provided for precise loading of the leakage current detection PCBA.

[0341] The press 205 is assembled with the dual-axis cylinder 202 via the connecting plate 204. It is used to set the mounting points of the matching pressure bar 206 in accordance with the requirements of the leakage current detection type PCBA. The pressure bar 206 is assembled on the press 205 to ensure reliable connection between the leakage current detection type PCBA and the probe (and needle sleeve) 209.

[0342] The magnetic ring clamp 212 is electrically connected to the probe (and needle sleeve) 209 for the transmission of leakage current signals.

[0343] The electrical aviation socket 211 is electrically connected to the probe (and pin sleeve) 209 and the intermediate relay group 14 for the transmission of electrical signals.

[0344] In this scheme, the current signal output branch in the test current signal output unit serves as an upper and lower limit adjustment switching circuit. This circuit switches the upper and lower limit outputs of the leakage current detection current signal according to the test requirements of the leakage current detection type PCBA.

[0345] The voltage signal output branch in the test voltage signal output unit serves as a voltage regulation drive control circuit. This circuit uses programmable adjustment of leakage current to detect the electrical parameters of the upper and lower limits of the voltage signal output.

[0346] The test result signal output unit serves as the trip test circuit. This circuit is the core circuit and is used to act as the trip unit of the leakage current detection type PCBA to identify the leakage current function test results.

[0347] This circuit is used to perform phase switching (via KA12) and self-locking (via KA9 and KA10) on the input leakage current detection voltage signal according to the testing requirements of leakage current detection type PCBA, to provide working electrical signals for leakage current detection type PCBA; to detect the tripping function (via KA13) and latch the result (via KA14), and to transmit the detection result to PLC 16.

[0348] For example, in this solution, the working process of the testing equipment includes:

[0349] Step 1: Connect to an external power source.

[0350] Step 2: Based on the testing requirements of the leakage current detection PCBA under test, set the excitation signals (including leakage current detection current signal and leakage current detection voltage signal) through PLC 16, and initialize and monitor the status of various modules such as the test mechanism, mechanical transmission equipment, and IO control equipment through PLC 16.

[0351] Step 3: Select the appropriate test procedure in the host computer connected to PLC 16 to control and switch the test procedure.

[0352] Step 4: Place the leakage current detection PCBA to be tested on the carrier board, trigger the start signal to make PLC 16 control the dual-axis cylinder 202 to move, and wait for the magnetic switch 203 or limit switch 201 to detect the test mechanism in place.

[0353] Step 5: The PLC 16 controls the circuit in the test current signal output unit and the test voltage signal output unit to output the excitation signal.

[0354] Step 6: The host computer controls the PLC 16 circuit to open the voltage signal channel, leakage current signal channel, and trip signal channel for the leakage current detection PCBA under test. At the same time, the PLC 16 monitors the functional test results of the leakage current detection PCBA at each station.

[0355] Step 7: PLC 16 transmits the detected functional test results to the host computer.

[0356] Building upon the advantages of any of the aforementioned solutions, this solution utilizes a semi-automatic leakage current detection PCBA testing device, capable of performing leakage current detection PCBA functional tests. Its pneumatically automated execution process allows for step-by-step control and monitoring of the testing flow, distinguishing leakage current detection PCBA boards at different workstations and marking defects in faulty leakage current detection PCBAs. Through modular design of the control system, testing system, output system, and input mechanisms, personnel only need to select the corresponding testing mechanism based on requirements and assemble it into the testing device, connecting it via standardized interfaces. On the software side, according to the required leakage current detection PCBA version testing requirements and testing flow, the corresponding program formula is selected and set up. These steps complete the upgrade and setup of the testing device.

[0357] The testing equipment proposed in this solution improves automation, reduces human intervention, and enhances human-computer interaction; standardization and modularization enable flexible configuration such as equipment replacement, reducing costs and enhancing practicality.

[0358] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention. The scope of the present invention is determined by the scope of the appended claims.

Claims

1. A leakage current detection type PCBA test circuit, characterized in that, include: Test current signal output unit, test voltage signal output unit and test result signal output unit; The test current signal output unit is used to output a leakage current detection current signal; The test current signal output unit is equipped with a current adjustment circuit, which is used to adjust the value of the leakage current detection current signal. The test voltage signal output unit is used to output a leakage current detection voltage signal; The test voltage signal output unit is equipped with a voltage adjustment circuit, which is used to adjust the value of the leakage current detection voltage signal. The leakage current detection current signal and the leakage current detection voltage signal are used to be applied to the PCBA to be tested; When the PCBA receives the leakage current detection current signal and the leakage current detection voltage signal, it outputs a leakage current protection signal. The test result output unit is configured to output a test result signal when the leakage current protection signal is received. The test result signal is used to indicate that the PCBA has passed the leakage current test.

2. The leakage current detection type PCBA test circuit as described in claim 1, characterized in that, The test current signal output unit includes a first transformer and at least one current signal output branch; The current signal output branch includes a numerically adjustable current-limiting resistor, a first relay, and a magnetic ring; The first winding terminal of the first transformer is electrically connected to the power supply. The current-limiting resistor is connected in series with the normally open contact of the first relay to form a first circuit with the second winding terminal of the first transformer. The wire of the first circuit passes through the magnetic ring. The output terminal of the magnetic ring is used to output the leakage current detection current signal.

3. The leakage current detection type PCBA test circuit as described in claim 2, characterized in that, The test current signal output unit also includes an ammeter, which is connected in series in the first circuit. The ammeter is used to display the value of the current in the first circuit.

4. The leakage current detection type PCBA test circuit as described in claim 1, characterized in that, The test voltage signal output unit includes at least one voltage signal output branch; The voltage signal output branch includes a voltage regulating motor, a voltage regulator, a second relay, a third relay, and a voltage regulating controller; The voltage regulation signal output terminal of the voltage regulator controller is electrically connected to the voltage regulation motor, and the voltage regulation signal output terminal is used to output a voltage regulation signal; The voltage regulating motor is connected to the voltage regulator, and the voltage regulating motor is used to adjust the output voltage of the voltage regulator according to the voltage regulation signal; The first winding of the voltage regulator is electrically connected to the power supply, and the second winding of the voltage regulator is connected to the voltage output terminal through the normally open contact of the second relay. The voltage output terminal is used to connect to the leakage current detection voltage output terminal, and the leakage current detection voltage output terminal is used to output the leakage current detection voltage signal; The coil of the second relay and the normally open contact of the third relay form a second circuit, and the first control terminal of the voltage regulator is electrically connected to the coil of the third relay.

5. The leakage current detection type PCBA test circuit as described in claim 4, characterized in that, The test voltage signal output unit also includes a reversing switch; The reversing switch is located at the voltage output terminal, and the second control terminal of the voltage regulator is electrically connected to the reversing switch. The reversing switch is used to switch the voltage output terminal to output a first voltage or a second voltage.

6. The leakage current detection type PCBA test circuit as described in claim 4, characterized in that, The test result output unit includes a fourth relay, a fifth relay, a sixth relay, and a seventh relay; The fourth relay and the fifth relay form a power-on self-locking structure. When the fourth relay is powered on, the fifth relay self-locks. When the fifth relay self-locks, the voltage output terminal remains continuously connected. The sixth relay and the seventh relay constitute a tripping structure, and the two ends of the leakage current protection signal input terminal are connected in series with the coil of the sixth relay. The leakage current protection signal input terminal is used to receive the leakage current protection signal, and the sixth relay is configured to power on when the PCBA outputs the leakage current protection signal. When the sixth relay is powered on, the fifth relay is disconnected, the seventh relay is self-locked, and when the seventh relay is self-locked, the test result output unit continuously outputs the test result signal.

7. The leakage current detection type PCBA test circuit as described in claim 6, characterized in that, The voltage output terminal includes a first output terminal and a second output terminal, and the leakage current detection voltage output terminal includes a third output terminal, a fourth output terminal, and a fifth output terminal; The first output terminal is electrically connected to the third output terminal, and the second output terminal is electrically connected to the fourth or fifth output terminal. The test result output unit also includes a switching switch, which is used to electrically connect the second output terminal to the fourth output terminal or to the fifth output terminal.

8. The leakage current detection type PCBA test circuit as described in claim 7, characterized in that, The test result output unit also includes a shunt resistor and an eighth relay; One end of the leakage current protection signal input terminal is also connected in series with the normally closed contact of the eighth relay and the normally closed contact can be switched, and the normally open contact of the eighth relay is also connected in series with the shunt resistor.

9. The leakage current detection type PCBA test circuit as described in claim 7, characterized in that, The output voltage of the third and fourth output terminals includes 220V, and the output voltage of the third and fifth output terminals includes 380V.

10. A leakage current detection type PCBA testing device, characterized in that, The test circuit includes any one of claims 1 to 9, and further includes a controller; The controller is connected to the test current signal output unit, the test voltage signal output unit, and the test result signal output unit; The controller is used to adjust the value of the leakage current detection current signal by controlling the test current signal output unit, adjust the value of the leakage current detection voltage signal by controlling the test voltage signal output unit, and receive the test result signal by the test result signal output unit.

11. The leakage current detection type PCBA testing equipment as described in claim 10, characterized in that, It also includes a touch screen, which is electrically connected to the controller and is used to communicate and interact with the controller, input test commands, and display test results. The input test command is used to adjust the value of the leakage current detection current signal and the value of the leakage current detection voltage signal.

12. The leakage current detection type PCBA testing equipment as described in claim 10, characterized in that, Also includes: A clamping linkage device is used to fix the leakage current detection type PCBA to be tested.

13. The leakage current detection type PCBA testing equipment as described in claim 12, characterized in that, The clamping linkage device includes: a dual-axis cylinder, a limit switch, a press, a pressure bar, and a carrier plate; The press is mechanically connected to the twin-axis cylinder via a connecting plate, and the press is used to provide the mounting points for the pressure bar; The limit switch is used for monitoring the movement position of the press. The carrier board is used to support the leakage current detection type PCBA.

14. The leakage current detection type PCBA testing equipment as described in claim 13, characterized in that, Also includes: The probe device includes: a needle bed and a probe; The carrier plate is movably mounted above the needle bed, and the probe is mounted on the needle bed. The probe is used to inject a leakage current detection signal into the leakage current detection type PCBA to be tested.

15. The leakage current detection type PCBA testing equipment as described in claim 10, characterized in that, Also includes: The test circuit includes a frame and a slide rail drawer, wherein the slide rail drawer is slidably connected to the frame and is used to house intermediate relays and AC contactors in the test circuit. The controller is electrically connected to the intermediate relay, and the controller controls the operation of the AC contactor through the intermediate relay.

16. The leakage current detection type PCBA testing equipment as described in claim 15, characterized in that, Also includes: A safety light curtain, which is mounted on the frame; The controller is connected to the safety light curtain, and the controller is configured to stop the leakage current test according to the safety detection signal of the safety light curtain; If a person or object enters the leakage current test area, the safety light curtain generates the safety detection signal.

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