Contactor and change-over switch main contact final pressure measuring device

Abstract

The utility model discloses a contactor and change-over switch main contact final pressure measuring device which comprises a pressure sensor, an analog-to-digital conversion module, a master control module, a power supply module and a display module, the pressure sensor is connected with the analog-to-digital conversion module, the analog-to-digital conversion module is connected with the master control module, and the display module is connected with the master control module. The pressure sensor, the analog-to-digital conversion module and the main control module are respectively connected with the power supply module, the pressure sensor is used for acquiring a pressure analog signal of the main contact, the analog-to-digital conversion module is used for converting the pressure analog signal into a pressure digital signal, and the main control module is used for receiving the pressure digital signal; and the pressure digital signal is processed to obtain a final pressure value of the main contact, and the display module is used for displaying the final pressure value of the main contact. According to the utility model, the pressure sensor is arranged between the moving contact and the static contact of the main contact, so that the detection is direct, errors are reduced, and meanwhile, the safety risk of harming operators due to springback of a spring scale is eliminated.

Description

Technical Field

[0001] The utility model relates to the technical field of measuring the final pressure of the main contact of a contactor, in particular to a device for measuring the final pressure of the main contact of a contactor and a change-over switch. Background Technique

[0002] A contactor is a device that can quickly cut off the AC and DC main circuits and can frequently connect and disconnect high-current control circuits. It is often used to control equipment such as electric locomotive motors and auxiliary fans. The contactor can not only connect and disconnect the circuit, but also has the function of low-voltage release protection. The contactor has a large control capacity and is suitable for frequent operation and remote control. It is an important electrical component in the main circuit of a locomotive. The function of the change-over switch on a locomotive is roughly similar to that of a contactor and is used for the conversion of the electric locomotive circuit.

[0003] The main contacts of the contactor and the change-over switch on a locomotive are the connection parts for the conduction of the main circuit, and the current passing through them is very large (up to 800 A). The electro-pneumatic contactor on a locomotive is driven by compressed air. The moving contact realizes contact and separation from the static contact under the drive of compressed air, thereby realizing the connection or disconnection of the circuit. After the moving and static contacts are in contact, there must be a certain pressure at the contact, and this pressure is called the final pressure of the main contact. The final pressure of the main contact is related to the current conduction ability. Within the scope of the maintenance regulations, the greater the final pressure of the main contact, the better the contact between the contacts and the smaller the contact resistance. Insufficient contact pressure will cause an increase in the contact resistance of the contacts, and the contacts will be burned out under high current, leading to accidents. Therefore, it is necessary to measure the final pressure of the main contact during manufacturing and maintenance, which is an important performance index for measuring the main contact of a contactor.

[0004] At present, the final pressure of the main contacts of contactors and change-over switches is usually measured by a spring scale throughout the railway. There are the following problems with using a spring scale for measurement:

[0005] 1) It is inconvenient to measure and there are certain safety hazards.

[0006] In actual measurement work, due to the special structure of contactors and change-over switches, it is not convenient to hook the main contact when using a spring scale to pull the main contact for measurement. Moreover, since the final pressure value of the main contact of a contactor is relatively large, generally greater than 200 N. Therefore, if the force is applied improperly or not hooked firmly during measurement, the hook of the spring scale will come off or the ejector rod will slide out, bouncing back to the measurer and causing personal injury.

[0007] 2) The error is large.

[0008] Due to its structural characteristics, the hand-held spring scale has low precision. After long-term use, the spring force of the spring scale changes, resulting in a greater deviation in the measured value. At the same time, in actual measurement work, due to the special structure of the contactor and the change-over switch, the spring scale cannot ensure horizontal measurement during measurement. This leads to the actual measurement result being the resultant force of the contact force of the contact head and the pulling force in the vertical direction, making the actual measured value larger than the true value. Utility Model Content

[0009] The purpose of the present utility model is to provide a device for measuring the final pressure of the main contact of a contactor and a change-over switch. By setting a pressure sensor between the moving and static contacts, the detection is direct, the error is reduced, and at the same time, the safety risk of spring-back injury to operators caused by using a spring scale is eliminated.

[0010] In order to achieve the above-mentioned utility model purpose, the technical solutions adopted by the present utility model are as follows:

[0011] According to one aspect of the present utility model, there is provided a device for measuring the final pressure of the main contact of a contactor and a change-over switch, including a pressure sensor, an analog-to-digital conversion module, a main control module, a power supply module, and a display module;

[0012] The pressure sensor is connected to the analog-to-digital conversion module, the analog-to-digital conversion module is connected to the main control module, the display module is connected to the main control module, and the pressure sensor, the analog-to-digital conversion module, and the main control module are respectively connected to the power supply module;

[0013] The pressure sensor is used to obtain the pressure analog signal of the main contact;

[0014] The analog-to-digital conversion module is used to convert the pressure analog signal into a pressure digital signal;

[0015] The main control module is used to receive the pressure digital signal and process the pressure digital signal to obtain the final pressure value of the main contact;

[0016] The display module is used to display the final pressure value of the main contact.

[0017] Preferably, the pressure sensor is arranged between the moving and static contacts of the main contact.

[0018] Preferably, the analog-to-digital conversion module includes an analog-to-digital conversion chip and a sensor connection terminal. The voltage stabilization circuit power supply pin and the digital power supply pin of the analog-to-digital conversion chip are both connected to the power supply module. The positive and negative input pins of the first channel of the analog-to-digital conversion chip are respectively connected to the sensor connection terminal. The pressure sensor is connected to the connection terminal. The serial port data output pin and the serial port clock pin of the analog-to-digital conversion chip are connected to the main control module.

[0019] Preferably, the main control module includes a main control chip. The voltage input pin of the main control chip is connected to the power supply module. The signal input / output pin PB0 of the main control chip is connected to the serial port clock pin of the analog-to-digital conversion chip. The signal input / output pin PB1 of the main control chip is connected to the serial port data output pin of the analog-to-digital conversion chip. The signal input / output pins PA9 and PA10 of the main control chip are respectively connected to the display module.

[0020] Preferably, the display module includes a display screen connection terminal. The signal receiving pin of the display screen connection terminal is connected to the signal input / output pin PA9 of the main control chip. The signal transmitting pin of the display screen connection terminal is connected to the signal input / output pin PA10 of the main control chip.

[0021] Preferably, the power supply module includes a battery management unit and a voltage stabilizing unit. The battery management unit is connected to the input voltage. The battery management unit is connected to the voltage stabilizing unit. The pressure sensor, the analog-to-digital conversion chip, and the main control chip are respectively connected to the voltage stabilizing unit.

[0022] Preferably, the battery management unit includes a battery management chip and a battery connection terminal. The first pin of the battery management chip is the voltage input terminal. The sixth and seventh pins of the battery management chip are respectively connected to the battery connection terminal. The eighth pin of the battery management chip is connected to the voltage stabilizing unit.

[0023] Preferably, the voltage stabilizing unit includes a voltage stabilizing chip. The eighth pin of the battery management chip is connected to the third pin of the voltage stabilizing chip. The fourth pin of the battery management chip is the voltage output pin.

[0024] In summary, due to the adoption of the above technical solutions, the beneficial effects of the present utility model are as follows:

[0025] By arranging a pressure sensor between the moving and static contacts of the main contact of the present utility model, the pressure sensor is used to detect the final pressure signal of the main contact, and the analog signal is converted into a digital signal through the analog-to-digital conversion chip, which is convenient for the main control chip to identify and process. Finally, the main control chip transmits the pressure value to the display screen for display. The detection is direct, the error is reduced, and at the same time, the safety risk of rebounding the spring scale to injure the operator is eliminated. Brief Description of the Drawings

[0026] Figure 1 is the circuit schematic diagram of the battery management unit of the present utility model;

[0027] Figure 2 is the circuit schematic diagram of the voltage stabilizing unit of the present utility model;

[0028] Figure 3 is the circuit schematic diagram of the analog-to-digital conversion module of the present utility model;

[0029] Figure 4 is the circuit schematic diagram of the main control module of the present utility model;

[0030] Figure 5 is the circuit schematic diagram of the display module of the present utility model;

[0031] Figure 6 is the circuit schematic diagram of the crystal oscillator of the present utility model. Specific Embodiments

[0032] In order to make the objectives, technical solutions and advantages of the present utility model clearer and more understandable, the following provides preferred embodiments with reference to the attached drawings and further elaborates on the present utility model in detail. However, it should be noted that many details listed in the specification are only for enabling the reader to have a thorough understanding of one or more aspects of the utility model, and these aspects of the present utility model can be implemented even without these specific details.

[0033] Please refer to Figure 1-6 , the present utility model provides a measuring device for the final pressure of the main contact of a contactor and a change-over switch, and the technical solution is as follows:

[0034] A measuring device for the final pressure of the main contact of a contactor and a change-over switch includes a pressure sensor, an analog-to-digital conversion module, a main control module, a power supply module and a display module. The pressure sensor is used to obtain the pressure analog signal of the main contact. The analog-to-digital conversion module is used to convert the pressure analog signal into a pressure digital signal. The main control module is used to receive the pressure digital signal and process the pressure digital signal to obtain the final pressure value of the main contact. The display module is used to display the final pressure value of the main contact.

[0035] Specifically, as Figure 1As shown in the figure, the power supply module includes a battery management unit and a voltage regulation unit. The battery management unit includes a battery management chip and battery connection terminals. The model of the battery management chip is IP5306-I2C. The first pin of the battery management chip is a voltage input pin, which is connected to an external voltage. At the first pin of the battery management chip, it is grounded through a capacitor E-C13. A series circuit composed of a resistor E-R8 and a capacitor E-C12 is connected in parallel on the capacitor E-C13. The second, third, and fourth pins of the battery management chip are LED signal pins. The second pin is connected to a light-emitting diode E-LED7, and a light-emitting diode E-LED8 is connected in parallel on the light-emitting diode E-LED7. The third pin is connected to a light-emitting diode E-LED9, and a light-emitting diode E-LED10 is connected in parallel on the light-emitting diode E-LED9. The fourth pin is connected to a resistor E-R28, and the end of the resistor E-R28 away from the fourth pin is respectively connected to the light-emitting diodes E-LED7, E-LED8, E-LED9, and E-LED10. The sixth pin is connected to the second pin of the battery connection terminal through a capacitor E-C44 and then grounded. The seventh pin is connected to the first pin of the battery connection terminal through an inductor E-L1. A parallel circuit of a resistor E-R26 and a resistor E-R27 is connected between the sixth and seventh pins. A capacitor E-C45 is connected between the first and second pins of the battery connection terminal. The eighth pin is a 5V voltage output pin, and the eighth pin is respectively grounded through capacitors E-C46, E-C47, E-C48, and E-C49. By connecting an external voltage through the battery management chip, a 5V output voltage can be directly obtained after passing through the battery management chip, and the 5V output voltage is then connected to the voltage regulation unit. It is also possible to connect a battery through the battery connection terminal to obtain a 5V output voltage from the battery. When the input voltage and the battery are connected simultaneously, a 5V output voltage can be directly provided, and the battery can also be charged.

[0036] As Figure 2 shown in the figure, the voltage regulation unit includes a voltage regulation chip. The model of the voltage regulation chip is AMS1117-3.3. The first pin of the voltage regulation chip is grounded. The second and fourth pins are 3.3V voltage output pins. The third pin is connected to the eighth pin of the battery management chip. The third pin is respectively grounded through capacitors WY-C31 and WY-C34. The fourth pin is respectively grounded through capacitors WY-C32 and WY-C33. The voltage regulation chip receives the 5V voltage output from the battery management chip and steps down the 5V voltage to obtain a 3.3V voltage output to provide a stable power supply voltage for each module.

[0037] As Figure 3As shown in the figure, the analog-to-digital conversion module includes an analog-to-digital conversion chip and a sensor connection terminal. The model of the analog-to-digital conversion chip is HX711. The 1st and 16th pins of the analog-to-digital conversion chip are the regulated power supply pin and the digital power supply pin respectively, both of which are connected to the 8th pin of the battery management chip. The 2nd pin of the battery management chip is connected to the triode H-Q1. The 3rd pin is grounded through the capacitor H-C1. The 4th pin is grounded through the resistor H-R2. The 5th pin is grounded. The 6th pin is grounded through the capacitor H-C2. The 7th and 8th pins are respectively connected to the sensor connection terminal. The model of the sensor connection terminal is H-U5. The sensor connection terminal has a total of 6 pins. The 2nd pin of the sensor connection terminal is connected to the 2nd and 4th pins of the voltage regulator chip. The 3rd pin of the sensor connection terminal is connected to the 8th pin of the analog-to-digital conversion chip through the resistor H-R3. The 4th pin of the sensor connection terminal is connected to the 7th pin of the analog-to-digital conversion chip. The 11th and 12th pins of the analog-to-digital conversion chip are respectively connected to the main control module. The pressure sensor is connected through the sensor connection terminal, and the pressure sensor is inserted between the main contacts. When the contactor operates, the main contacts directly press on the pressure sensor. Due to the action of the pressure, the pressure is always perpendicular to the surface of the pressure sensor. The pressure sensor detects the pressure analog signal of the main contacts, transmits the pressure signal analog signal to the analog-to-digital conversion chip, converts the pressure analog signal into a pressure digital signal through the analog-to-digital conversion chip, and transmits the pressure digital signal to the main control module. By detecting the pressure of the main contacts through the pressure sensor, the problem that the measuring force and the actual final pressure of the contactor are not on the same straight line is eliminated, and the measurement error is greatly reduced.

[0038] As Figure 4 described, the main control module includes a main control chip. The model of the main control chip is STM32F103C8T6. The 24th pin of the main control chip is connected to the 2nd and 4th pins of the voltage regulator chip. The 18th pin of the main control chip is connected to the 11th pin of the analog-to-digital conversion chip. The 19th pin of the main control chip is connected to the 12th pin of the analog-to-digital conversion chip. The 30th and 31st pins of the main control chip are respectively connected to the display module. The main control chip receives the pressure digital signal transmitted by the analog-to-digital conversion chip, processes the pressure digital signal, and outputs the pressure display signal to the display module.

[0039] As Figure 5 shown, the display module includes a display screen connection terminal. The model of the display screen connection terminal is PM-U20. The display screen connection terminal has 6 pins. The 2nd pin is connected to the 30th pin of the main control chip. The 3rd pin of the display screen connection terminal is connected to the 31st pin of the main control chip. The 4th pin of the display screen connection terminal is connected to the 8th pin of the battery management chip. The display screen is connected through the display screen connection terminal, and the pressure display signal transmitted by the main control chip is displayed through the display screen, which is convenient for the staff to view and record.

[0040] Further, as Figure 6 shown, it further includes a crystal oscillator circuit, which includes a first crystal oscillator J-X2 and a second crystal oscillator J-X4. One end of the first crystal oscillator J-X2 is connected to the 3rd pin of the main control chip and grounded through a capacitor J-C39. The other end of the first crystal oscillator J-X2 is connected to the 4th pin of the main control chip and grounded through a capacitor J-C40. One end of the second crystal oscillator J-X4 is connected to the 5th pin of the main control chip, and the other end of the second crystal oscillator J-X4 is connected to the 6th pin of the main control chip. The crystal oscillator circuit provides a stable clock frequency for the main control chip and guarantees the stable operation of the whole device.

[0041] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A measuring device for the final pressure of the main contacts of a contactor and a change-over switch, characterized in that It includes a pressure sensor, an analog-to-digital conversion module, a main control module, a power supply module and a display module; The pressure sensor is connected to the analog-to-digital conversion module, the analog-to-digital conversion module is connected to the main control module, the display module is connected to the main control module, and the pressure sensor, the analog-to-digital conversion module and the main control module are respectively connected to the power supply module; The pressure sensor is used to obtain the pressure analog signal of the main contact; The analog-to-digital conversion module is used to convert the pressure analog signal into a pressure digital signal; The main control module is used to receive the pressure digital signal and process the pressure digital signal to obtain the final pressure value of the main contact; The display module is used to display the final pressure value of the main contact.

2. The main contact final pressure measuring device for a contactor and a change-over switch according to claim 1, wherein: The pressure sensor is arranged between the moving and static contacts of the main contact.

3. A main contact final pressure measuring device for a contactor and a change-over switch according to claim 1, characterized in that: The analog-to-digital conversion module includes an analog-to-digital conversion chip and a sensor connection terminal. The voltage stabilization circuit power supply pin and the digital power supply pin of the analog-to-digital conversion chip are both connected to the power supply module. The positive and negative input pins of the first channel of the analog-to-digital conversion chip are respectively connected to the sensor connection terminal. The pressure sensor is connected to the connection terminal. The serial port data output pin and the serial port clock pin of the analog-to-digital conversion chip are connected to the main control module.

4. A measuring device for the final pressure of the main contacts of a contactor and a change-over switch according to claim 3, characterized in that: The main control module includes a main control chip. The voltage input pin of the main control chip is connected to the power supply module. The signal input / output pin PB0 of the main control chip is connected to the serial port clock pin of the analog-to-digital conversion chip. The signal input / output pin PB1 of the main control chip is connected to the serial port data output pin of the analog-to-digital conversion chip. The signal input / output pin PA9 and the signal input / output pin PA10 of the main control chip are respectively connected to the display module.

5. A measuring device for the final pressure of the main contacts of a contactor and a change-over switch according to claim 4, characterized in that: The display module includes a display screen connection terminal. The signal receiving pin of the display screen connection terminal is connected to the signal input / output pin PA9 of the main control chip. The signal transmitting pin of the display screen connection terminal is connected to the signal input / output pin PA10 of the main control chip.

6. The main contact final pressure measuring device for a contactor and a change-over switch according to claim 4, characterized in that: The power supply module includes a battery management unit and a voltage stabilization unit. The battery management unit is connected to the input voltage. The battery management unit is connected to the voltage stabilization unit. The pressure sensor, the analog-to-digital conversion chip and the main control chip are respectively connected to the voltage stabilization unit.

7. A measuring device for the final pressure of the main contacts of a contactor and a change-over switch according to claim 6, characterized in that: The battery management unit includes a battery management chip and a battery connection terminal. The first pin of the battery management chip is the voltage input terminal. The sixth and seventh pins of the battery management chip are respectively connected to the battery connection terminal. The eighth pin of the battery management chip is connected to the voltage stabilization unit.

8. A measuring device for the final pressure of the main contact of a contactor and a change-over switch according to claim 7, characterized in that: The voltage stabilization unit includes a voltage stabilization chip. The eighth pin of the battery management chip is connected to the third pin of the voltage stabilization chip. The fourth pin of the battery management chip is the voltage output pin.

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