DC brushless PCBA test fixture control system

Abstract

The utility model discloses a DC brushless PCBA test fixture control system, comprising a test fixture in which a PCBA is arranged, and positive and negative interfaces of a PCBA power supply are connected and controlled by a power relay; the PCBA phase line interface and an external motor are connected and controlled by a power relay; the PCBA program burning interface and an external programmer are connected and controlled by a small-signal relay; the PCBA control interface and the clamp controller are connected and controlled through an optical coupler or a high-impedance circuit. The clamp controller is connected with and controls on and off of the power relays and the small signal relays and sends a control command to the PCBA control interface; and the voltage sample testing circuit is used for collecting positive and negative electrode interface voltages of the PCBA power supply. According to the utility model, the burning test is fully automatic, and the manual operation is simplified. And under the condition that the production efficiency and the product yield are improved, the production cost is greatly reduced, and the requirements on testers are also reduced. And when one person operates a plurality of testers to work, the number of testers in the link can be completely reduced.

Description

Technical Field

[0001] The utility model relates to the field of PCBA testing, and particularly to a control system for a DC brushless PCBA testing fixture. Background Art

[0002] The newly produced PCBA still needs to go through steps such as MCU code burning and PCBA function testing to ensure that the produced PCBA is a good product, which is also an important link in product production quality assurance. At present, there are two means to realize the testing link: manual testing and fully automated testing. Manual testing is realized by means of a testing fixture. Each action during its burning, testing and testing process needs to be manually operated, and the final test result also needs to be manually judged. Due to the participation of a large number of manual operations, in the case of long-term work, problems such as missed function testing and misjudgment of results will occur, resulting in a decrease in the yield. Each action of the fully automated one is operated and judged by the machine, without those problems of manual operation. Although automated equipment is superior to manual work, automated equipment has high requirements for products. Only in the case of a single product and a large quantity, is it valuable to achieve full automation. Moreover, the equipment needs to be customized, with a long development cycle, high cost and requirements for the production site, which is not conducive to use in all environments. Therefore, most of the current production tests are mainly manual tests. Because manual testing has a wide range of adaptability, has no requirements for product functions, structures and quantities, and only needs a set of fixtures with low cost and simplicity to realize testing. Content of the Utility Model

[0003] The purpose of the utility model is to solve the problem points generated by manual testing and the fitting problem between the product itself and the fixture. The utility model miniaturizes the controller of the automated control equipment and combines it with the manual testing fixture to realize the intelligence of the testing fixture. Simplify manual operations and improve testing efficiency and product production quality.

[0004] The technical solution of the utility model is as follows:

[0005] A control system for a DC brushless PCBA testing fixture, comprising:

[0006] A testing fixture, inside which a PCBA is arranged; the testing fixture is powered by a fixture control power supply; the positive and negative power interfaces of the PCBA are connected and controlled by a first power relay; the phase wire interface of the PCBA is connected and controlled by a second power relay to an external motor; the program burning interface of the PCBA is connected and controlled by a small signal relay to an external programmer; the control interface of the PCBA is connected and controlled by an optocoupler or a high-impedance circuit to a fixture controller;

[0007] A fixture controller, which connects and controls the on-off of each power relay and small signal relay, and sends control commands to the control interface of the PCBA;

[0008] A voltage sampling circuit that collects the voltages at the positive and negative power supply interfaces of the PCBA and transmits them to the fixture controller.

[0009] Preferably, the negative power supply interface of the PCBA is connected to the SGND pin of the programming port. Detecting that the SGND pin is closed or short-circuited with the negative pole indicates that the fixture is pressed down, the PCBA is connected to the fixture, and the test is automatically started.

[0010] Preferably, the fixture controller realizes automatic code burning by accessing the start burn signal START, burn complete signal OK, and burn error signal NG of the burner, thus realizing integrated burning and testing and automation.

[0011] Preferably, the voltage sampling circuit adopts a differential operational amplifier voltage sampling circuit, and directly connects both ends of the voltage sampling to the positions closest to the positive and negative power supplies of the PCBA.

[0012] Preferably, it further includes an LED display screen connected to the fixture controller, which displays real-time data information, test status, and fault information.

[0013] Preferably, the fixture controller is connected to multiple test fixtures through an on-line signal line to realize multi-fixture time-sharing working tests.

[0014] Preferably, it further includes a buzzer connected to the fixture controller to indicate whether the test passes or fails.

[0015] Preferably, it further includes operation buttons connected to the fixture controller to set different configurations so that the controller is compatible with different test fixtures and PCBA.

[0016] The advantages of the present utility model are:

[0017] Compared with traditional manual testing and fully automated testing, the present utility model has a comparable cost performance and flexibility to manual testing equipment, and also has fully automated burning and testing processing, simplifying manual operations. While improving production efficiency and product yield, it significantly reduces production costs and also reduces the requirements for testers themselves. And when one person operates multiple units, it is completely possible to reduce the number of testers in this link. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The following further describes the present utility model in conjunction with the drawings and embodiments:

[0019] Figure 1 is a schematic block diagram of the DC brushless PCBA test fixture control system of the present utility model;

[0020] Figure 2 is a schematic diagram of the principle of the differential operational amplifier voltage sampling circuit. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] As Figure 1 shown, the DC brushless PCBA test fixture control system proposed by the present utility model includes:

[0022] A test fixture with a PCBA disposed therein; the test fixture is powered by a fixture control power supply; the positive and negative power interfaces of the PCBA are connected and controlled by a first power relay; the phase wire interface of the PCBA is connected and controlled by a second power relay to an external motor; the program burning interface of the PCBA is connected and controlled by a small signal relay to an external programmer; the control interface of the PCBA is connected and controlled by an optocoupler or a high-impedance circuit to a fixture controller;

[0023] A fixture controller that connects and controls the on / off of each power relay and small signal relay, and sends control commands to the PCBA control interface;

[0024] A voltage sampling circuit that collects the voltage of the positive and negative power interfaces of the PCBA and transmits it to the fixture controller;

[0025] An LED display screen that is connected to the fixture controller and displays real-time data information, test status, and fault information;

[0026] A buzzer that is connected to the fixture controller to indicate whether the test passes or fails;

[0027] A button that is connected to the fixture controller to set different configurations so that the controller is compatible with different test fixtures and PCBA.

[0028] This system adopts an isolation design. The positive and negative power interfaces of the PCBA are connected and controlled by a power relay to the fixture control power supply; the phase wire interface of the PCBA is connected and controlled by a power relay to an external motor; the program burning interface of the PCBA is connected and controlled by a small signal relay to an external programmer; the control interface of the PCBA is connected and controlled by an optocoupler or a high-impedance circuit, etc., to the fixture controller. Through the above design, the mutual influence between devices can be eliminated, and the risk of PCBA damage caused by the problem of incompatibility between multi-power devices can be reduced.

[0029] This controller automatically recognizes the connection between the PCBA and the fixture to achieve a more intelligent test. In order to support the transformation of old fixtures and without adding any peripheral sensors, this controller utilizes the SGND of the PCBA programming port and the negative pole of the power supply. Since the negative pole of the PCBA power supply is connected to the SGND of the programming port, as long as it is detected that SGND and the negative pole are closed or short-circuited, it means that the fixture is pressed down and the PCBA is connected to the fixture, and the test can be automatically started.

[0030] Implement automatic MCU code burning. Currently, most programmers support communication control with the machine to achieve batch automatic burning of MCUs. Combining this function, the fixture controller can achieve automatic code burning by accessing the START signal (start burning), OK signal (burning completed), and NG signal (abnormal burning) of the programmer, thus realizing integrated burning and testing and automation.

[0031] Automatic judgment of test items to reduce manual misjudgment or omission. In the PCBA test of brushless vacuum cleaners, customers have high requirements for the power accuracy of the vacuum cleaner, which must be within a certain range. However, due to the inability of existing supporting equipment to achieve automatic judgment currently, manual identification is required, and there is also a problem of large power deviation. Due to the long power cord between the power supply equipment and the PCBA power interface, when the current is large, there is a large voltage drop or loss on the power cord, resulting in the power display being higher than the actual operating power of the PCBA. To solve such problems, the fixture control board adopts a differential operational amplifier voltage sampling circuit, such as Figure 2 shown, which can directly connect both ends of the voltage sampling to the positions closest to the positive and negative poles of the PCBA power supply, eliminating the influence of line loss and making the power display close to the actual value. By adjusting the minimum and maximum values of the power judgment of the fixture controller, automatic judgment of test items such as PCBA power can be achieved. At the same time, the controller will record the power and quantity, and through the LED display screen, the normal distribution diagram of power and quantity will be displayed in real time, facilitating data analysis of product batches.

[0032] Multiple units are connected in series for time-sharing testing. When sharing a single programmer and test power supply, simply connect the online signal lines of the fixture controllers to achieve time-sharing operation and testing of multiple units. The online signal can also be called the busy signal. When a certain fixture is working, this signal is at a low level, and when the work is completed, this signal returns to a high level. When another fixture detects a non-busy state during continuous waiting, it will immediately start working and pull this signal to a low level, and so on in a cycle to achieve time-sharing testing of multiple machines.

[0033] Adopt multi-faceted and differentiated information prompts. The controller has two types of information prompts, one is visual, i.e., information prompts on the display screen, and the other is auditory, i.e., buzzer prompts. The content of the display screen prompt is relatively rich. In addition to displaying real-time data information, there are corresponding prompt methods for the test status and fault information respectively. Among them, the color is green, indicating that the test item passes, and the color is red, indicating that the test item fails. The buzzer prompt is relatively simple. When the test passes, the buzzer gives a single beep, and when the test fails, the buzzer gives a rapid continuous alarm sound.

[0034] The controller can perform human-computer interaction. By operating the buttons and viewing the display screen, different configurations can be set to make the controller compatible with more test fixtures and PCBAs.

[0035] The utility model adds a micro control board on the basis of an artificial test fixture to replace the artificial operation steps and judgments. Currently, only manual loading and unloading are required. After simplifying the operation, one or more fixtures can be operated manually at the same time, thus increasing the production output. At the same time, some defects of the fixture itself are also solved. In the process of testing the brushless PCBA product, since the brushless motor needs to be connected during the testing process, after the testing is completed, the motor needs 5 to 10 seconds to stop under the action of inertia. Because the electrolytic capacitor of the PCBA needs to be discharged after the testing is completed, but due to the reaction of the motor, the discharge time will become very long, which is extremely unfavorable for production. If the discharge treatment is not carried out, there is a high risk of damage to the PCBA during the production process. To solve this problem, a circuit for disconnecting the connection between the PCBA and the motor is added to the fixture control board. After the testing is completed, the controller will judge to disconnect the motor connection after the PCBA output is turned off, completely separating the PCBA from the motor. At this time, automatic discharge is carried out, and it will no longer be affected by the motor, and it can be completed within 1 second or a shorter time.

[0036] The above embodiments are only used to illustrate the technical concept and features of the present invention, and the purpose is to enable those who are familiar with this technology to understand the content of the present invention and implement it accordingly, and it cannot be used to limit the protection scope of the present invention. All modifications made according to the spirit of the main technical solution of the present invention should be covered within the protection scope of the present invention.

Claims

1. A DC brushless PCBA test fixture control system, characterized in that, Including: A test fixture with a PCBA installed inside; The test fixture is powered by a fixture control power supply; the positive and negative power supply interfaces of the PCBA are connected and controlled by a first power relay; The phase wire interface of the PCBA is connected and controlled by a second power relay to an external motor; the program burning interface of the PCBA is connected and controlled by a small signal relay to an external programmer; the control interface of the PCBA is connected and controlled by an optocoupler or a high-impedance circuit to a fixture controller; A fixture controller that connects and controls the on / off of each power relay and small signal relay, and sends control commands to the PCBA control interface; A voltage sampling circuit that collects the voltages of the positive and negative power supply interfaces of the PCBA and transmits them to the fixture controller.

2. The DC brushless PCBA test fixture control system according to claim 1, wherein, The negative power supply interface of the PCBA is connected to the SGND pin of the burning port. Detecting that the SGND pin is closed or shorted to the negative pole indicates that the fixture is pressed down, the PCBA is connected to the fixture, and the test is automatically started.

3. The DC brushless PCBA test fixture control system according to claim 1, wherein The fixture controller realizes automatic code burning by accessing the start burning signal START, the burning completion signal OK, and the burning abnormal signal NG of the programmer, thus realizing integrated burning and testing and automation.

4. The DC brushless PCBA test fixture control system according to claim 1, wherein The voltage sampling circuit adopts a differential operational amplifier voltage sampling circuit, and directly connects both ends of the voltage sampling to the positions closest to the positive and negative power supplies of the PCBA.

5. The DC brushless PCBA test fixture control system according to claim 4, wherein It also includes an LED display screen connected to the fixture controller, which displays real-time data information, test status, and fault information.

6. The DC brushless PCBA test fixture control system according to claim 1, characterized in that, The fixture controller is connected to multiple test fixtures through an on-line signal line to realize multi-fixture time-sharing working tests.

7. The DC brushless PCBA test fixture control system according to claim 1, characterized in that, It also includes a buzzer connected to the fixture controller to indicate whether the test passes or fails.

8. The DC brushless PCBA test fixture control system according to claim 1, wherein It also includes operation buttons connected to the fixture controller to set different configurations to make the controller compatible with different test fixtures and PCBA.

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