Safety relay contact pressure electronic force measuring circuit and electronic force measurer

Abstract

The present application belongs to the technical field of railway signal equipment, and particularly relates to a safety relay contact pressure electronic force measuring circuit and an electronic force measuring device. The safety relay contact pressure electronic force measuring circuit comprises a contact state monitoring circuit, one end of which is connected with a relay contact for capturing the state of the relay contact; a pressure detection circuit, one end of which is connected with the other end of the contact state monitoring circuit; and a signal conditioning circuit, one end of which is connected with the contact state monitoring circuit through a relay, and the other end of which is connected with the pressure detection circuit. The electronic force measuring device comprises the above circuit. The safety relay contact pressure electronic force measuring circuit and the electronic force measuring device provided by the present application make the measurement of the contact pressure electrically automatic, eliminate manual errors, and improve the detection accuracy.

Description

Technical Field

[0001] This invention belongs to the technical field of railway signaling equipment, specifically relating to a safety relay contact pressure electronic force measuring circuit and electronic force measuring device. Background Technology

[0002] Safety relays in railway signaling equipment are among the most important electrical components related to train operation safety. The reliable operation of relays mainly depends on the electrical characteristics of their contacts, which in turn depend on whether the contact pressure is within acceptable limits.

[0003] To ensure the safe operation of relays, it is necessary to periodically check the contact pressure of safety relays. Currently, the main method for measuring relay contact pressure is a mechanical force gauge, which works by using a lever to drive a spiral spring, which in turn drives an indicator pointer to measure the contact pressure. However, due to the structural characteristics of mechanical force gauges, the pressure value needs to be read manually, resulting in significant systematic and human errors. Furthermore, the measurement data cannot be digitized, leading to low reliability.

[0004] To address the aforementioned problems, this invention provides a safety relay contact pressure electronic force measuring circuit and an electronic force measuring device. Summary of the Invention

[0005] One object of the present invention is to solve at least the above-mentioned problems and to provide at least the advantages that will be described later.

[0006] Another objective of this invention is to provide an electronic force measuring circuit for the pressure of a safety relay contact, which makes the relay contact pressure measurement data stable and reliable, the data transmission fast and accurate, and facilitates data analysis and storage.

[0007] Another objective of this invention is to provide an electronic force gauge that is simple and easy to operate, automates the measurement of contact pressure, eliminates human error, and improves detection accuracy.

[0008] To achieve these objectives and other advantages according to the present invention, the present invention provides a safety relay contact pressure electronic force measuring circuit, comprising:

[0009] A contact status monitoring circuit, one end of which is connected to a relay contact to capture the relay contact status;

[0010] A pressure detection circuit, one end of which is connected to the other end of the contact status monitoring circuit;

[0011] The signal conditioning circuit has one end connected to the contact status monitoring circuit via a relay, and the other end connected to the pressure detection circuit.

[0012] Preferably, the signal conditioning circuit includes a micro-force sensor, a filter circuit, and an amplification conditioning circuit. One end of the micro-force sensor is connected to the contact status monitoring circuit through the relay, and the other end is connected to the input terminal of the filter circuit. The output terminal of the filter circuit is connected to the input terminal of the amplification conditioning circuit, and the output terminal of the amplification conditioning circuit outputs a contact pressure signal.

[0013] Preferably, the filter circuit includes resistors R20 and R21, capacitors C31, C29, and C30. The input terminal of resistor R20 is connected to one output terminal of the micro-force sensor, and the output terminal of resistor R20 is connected between capacitors C31 and C29. The input terminal of resistor R21 is connected to the other output terminal of the micro-force sensor, and the output terminal of resistor R21 is connected between capacitors C29 and C30.

[0014] Preferably, the amplification and conditioning circuit includes an operational amplifier U3, the two ends of the input of the operational amplifier U3 are connected to the micro-force sensor, and the output of the operational amplifier U3 outputs a contact pressure signal.

[0015] Preferably, the pressure detection circuit includes a first central processing unit, an attitude sensor, a display, an interface chip, and multiple peripheral circuits. The attitude sensor is connected to the first central processing unit, and the display and the interface chip are respectively connected to the first central processing unit through the peripheral circuits.

[0016] The signal conditioning circuit is connected to the pressure detection circuit via the first central processing unit.

[0017] Preferably, the interface chip is connected to the contact status monitoring circuit.

[0018] Preferably, the display is an OLED display.

[0019] Preferably, the contact status monitoring circuit includes a second central processing unit with multiple pins connected to multiple contacts on the relay to capture the contact status of the relay.

[0020] Preferably, it also includes a host computer, which is connected to the contact status monitoring circuit.

[0021] An electronic force gauge, comprising:

[0022] The above-mentioned safety relay contact pressure electronic force measurement circuit.

[0023] The present invention has at least the following beneficial effects:

[0024] 1. The present invention provides a safety relay contact pressure electronic force measuring circuit, which uses an attitude sensor and a micro-force sensor, enabling the attitude sensor to monitor the magnitude and direction of the force applied by the micro-force sensor in real time.

[0025] 2. The present invention provides an electronic force measuring circuit for the contact pressure of a safety relay, which realizes an automatic measurement method for the contact pressure of railway safety relays, improving measurement efficiency and the reliability of measurement data.

[0026] 3. The present invention provides a safety relay contact pressure electronic force measuring circuit, which realizes the automated testing of safety relays.

[0027] 4. The electronic force measuring device provided by this invention has a simple structure, low cost, and market competitiveness, and can realize micro-force testing of various railway equipment. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the electronic force measuring circuit for the safety relay contact pressure described in this invention;

[0029] Figure 2 This is the schematic diagram of the signal conditioning circuit.

[0030] Figure 3 This is a schematic diagram of the pressure detection circuit.

[0031] Figure 4 This is a schematic diagram of the contact status monitoring circuit.

[0032] Figure 5 This is a connection diagram of the relay contacts;

[0033] Among them, 1-micro force sensor, 2-attitude sensor, 3-host computer, first central processing unit CPU1, second central processing unit CPU2, interface chip U4, and relay U8. Detailed Implementation

[0034] The present invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0035] In this specification, when an element is referred to as "connected to or coupled to" another element or "located in another element," it may be "directly" connected to or coupled to the other element or "directly" located in the other element. Alternatively, it may be connected to or coupled to the other element or located in the other element with other elements interposed therebetween, unless it is specifically described as "directly coupled to or connected to" the other element or "directly located" in the other element. Furthermore, it should be understood that when an element is referred to as "on another element," "above another element," "below another element," or "under another element," it may be in "direct" contact with the other element or in contact with the other element through which other elements are interposed, unless it is specifically referred to as being in direct contact with the other element.

[0036] like Figure 1 As shown, the present invention provides a safety relay contact pressure electronic force measuring circuit, comprising:

[0037] A contact status monitoring circuit, one end of which is connected to a relay contact to capture the relay contact status;

[0038] A pressure detection circuit, one end of which is connected to the other end of the contact status monitoring circuit;

[0039] The signal conditioning circuit has one end connected to the contact status monitoring circuit via a relay, and the other end connected to the pressure detection circuit.

[0040] This invention uses a contact status monitoring circuit to determine which contact on the relay is open or closed, and then notifies the pressure detection circuit through the UART1 interface. After receiving the status signal from the contact status monitoring circuit, the pressure detection circuit can read the differential analog signal of the contact pressure from the force sensor circuit in the signal conditioning circuit, perform AD conversion, and calculate the digital value of the contact pressure inside the pressure detection circuit. The contact pressure test function cannot be completed by force measurement and transmission alone; the contact status monitoring circuit must realize the transient capture function of the departure of dynamic and static contact pressure.

[0041] The automatic measurement method for railway safety relay contact pressure implemented in this invention improves measurement efficiency and the reliability of measurement data.

[0042] Based on the above embodiments, such as Figure 2 As shown, the signal conditioning circuit includes a micro-force sensor 1, a filter circuit, and an amplification conditioning circuit. One end of the micro-force sensor 1 is connected to the contact status monitoring circuit through the relay, and the other end is connected to the input terminal of the filter circuit. The output terminal of the filter circuit is connected to the input terminal of the amplification conditioning circuit, and the output terminal of the amplification conditioning circuit outputs the contact pressure signal.

[0043] The contact pressure is output to the filter circuit through the FS+ and FS- terminals of the micro-force sensor 1. The filter circuit includes resistors R20 and R21, and capacitors C31, C29, and C30. The input terminal of resistor R20 is connected to one output terminal of the micro-force sensor, and the output terminal of resistor R20 is connected between capacitors C31 and C29. The input terminal of resistor R21 is connected to the other output terminal of the micro-force sensor, and the output terminal of resistor R21 is connected between capacitors C29 and C30.

[0044] Specifically, the amplification and conditioning circuit includes an operational amplifier U3. The two ends of the input of the operational amplifier U3 are connected to the micro-force sensor through resistors R20 and R21 respectively. The output of the operational amplifier U3 outputs a contact pressure signal FS.

[0045] Based on the above embodiments, specifically, as follows: Figure 3 As shown, the pressure detection circuit includes a first central processing unit (CPU1), an attitude sensor 2, a display, an interface chip, and multiple peripheral circuits. The attitude sensor is connected to the first CPU, and the display and interface chip are respectively connected to the first CPU through the peripheral circuits. The interface chip is connected to the contact status monitoring circuit. The display is an OLED screen.

[0046] The signal conditioning circuit is connected to the pressure detection circuit via the first central processing unit.

[0047] Specifically, the peripheral circuit of CPU1 includes resistors R6, R1, R2, R3, and R4. When CPU1 receives the status signal from the contact status monitoring circuit, it can read the differential analog signal of the contact pressure from the micro-force sensor in the signal conditioning circuit, perform AD conversion, and calculate the digital value of the contact pressure within the CPU1 circuit. That is, when the FS signal arrives, it reaches CPU1 through pin 7. CPU1 converts the pressure signal into a digital value of 0 to 65535 through internal AD conversion. The CPU then performs Kalman filtering and quantization transformation on this digital value to convert it into a force value of 0 to 2500 mN. CPU1 then converts the pressure signal output by the pressure detection circuit into a force value.

[0048] Simultaneously, attitude sensor 2 monitors the direction of the force applied by micro-force sensor 1 in real time and outputs attitude signals S1 and S2 to pins 10 and 11 of the CPU. These attitude signals, in conjunction with Kalman filtering, complete the prediction of the true value of the micro-force. After the prediction of the true value of the micro-force is completed, CPU 1 sends the force value to the OLED display screen through pins 2, 3, 8, and 9 via resistors R1, R2, R3, and R4 for display.

[0049] This invention converts physical quantities in nature into electrical signals, and then converts the electrical signals into digital quantities, making the measurement data stable and reliable, the data transmission fast and accurate, and facilitating data analysis and storage.

[0050] Specifically, the interface circuit includes an interface chip U4, capacitors C11, C13, C20, and resistor R12. The interface chip is connected to the output terminal of the communication circuit. That is, the force value is output to pins 11 and 12 of the interface chip U4 through pins 5 and 6 of the UART port of CPU1. The data is input to the UART1 interface through pins 13 and 14 of U4, and then input to the contact status monitoring circuit through the UART1 interface.

[0051] Based on the above, specifically, such as Figure 4 As shown, the contact status monitoring circuit includes a second central processing unit with multiple pins connected to multiple contacts on the relay to capture the contact status of the relay.

[0052] The circuit consists of a central processing unit CPU2, whose 16 pins monitor the status of 16 sets of contacts: 8 sets of rear contacts (H1-break to H8-break) and 8 sets of front contacts (Q1-break to Q8-break), which are connected to the moving and stationary contacts of the relay respectively. When the force gauge moves the moving contact, it is used to capture the instantaneous pressure value when the moving and stationary contacts separate, i.e., the contact pressure.

[0053] When any contact state changes, CPU2 can enter interrupt processing, determine which contact has opened or closed, and then notify the pressure detection circuit through the attitude sensing circuit to collect the signal from the micro-force sensor and complete the measurement, display, and uploading of the contact pressure.

[0054] Specifically, in combination Figure 3 , Figure 4 and Figure 5 As shown, the contact status monitoring circuit CPU2 monitors the status of the first 8 contacts Q1-Q8 and the 8 contacts H1-H8 in the contact group in real time. However... Figure 5 Only four relay contacts Q1 to Q4 are represented; the signals for other contacts (Q5 to Q8, H1 to 8) are represented similarly.

[0055] When Q1 is disconnected, the output Q1-Break of relay U8 goes high. This high level is input to pin 8 of microcontroller CPU2. After receiving the high signal from pin 8, microcontroller CPU2 sends a contact state change signal to microcontroller CPU1 via signals TX1 and RX1 on pins 36 and 37. Interface chip U4 receives the contact state change signal from CPU2 via pins 13 and 14, and transmits it to pins 5 and 6 of microcontroller CPU1 via pins 11 and 12. After receiving the contact state change signal via pins 5 and 6, microcontroller CPU1 reads the contact pressure signal FS from the signal conditioning circuit via pin 7. Signal FS is converted to a digital value internally by an AD converter and calibrated to a pressure value of 0-2500mN.

[0056] The microcontroller CPU1 transmits the digital pressure value to pins 11 and 12 of the interface chip U4 via pins 5 and 6. U4 then transmits the value back to CPU2 via pins 13 and 14. After receiving the digital pressure value via pins 36 and 37, CPU2 packages the contact numbers of the changing states into a data structure. CPU2 then uploads the packaged data to the host computer PC via pins 4 and 5, thus completing one contact pressure measurement.

[0057] The working principle of this invention is as follows:

[0058] The contact status detection circuit CPU2 monitors the status of the first eight contacts Q1-Q8 and the last eight contacts H1-H8 in real time. When a contact is open, it indicates that the micro-force sensor has opened the contact. The contact status monitoring circuit notifies the pressure measurement circuit CPU1 via the UAR1 interface. After receiving the status signal from the contact status monitoring circuit, CPU1 reads the differential analog signal of the contact pressure from the signal conditioning circuit, performs AD conversion, and calculates the digital value of the contact pressure internally. CPU1 displays the calculated digital pressure on the display screen and simultaneously sends it to the contact status detection circuit CPU2 via UAR1. After receiving the digital pressure signal, the contact status detection circuit CPU2 adds the contact number information, repackages the data, and transmits it to the host computer via the RS232 interface. The host computer APP displays and saves the received contact pressure and contact number on the human-machine interface and determines whether the contact pressure value is qualified.

[0059] The present invention also provides an electronic force measuring device, including the aforementioned electronic force measuring circuit for the safety relay contact pressure. Since the connection method of the electronic components and the signal flow are the same as those of the circuit described above, they will not be described again.

[0060] The electronic force measuring circuit and electronic force gauge for safety relay contact pressure provided by this invention realize an automatic method for measuring the contact pressure of railway safety relays, improving measurement efficiency and the reliability of measurement data. Combined with the company's safety relay test bench, it enables automated testing of all safety relay items, while also increasing the technical added value of the relay testing equipment. The provided force gauge can be extended to achieve micro-force testing of various railway equipment.

[0061] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. It can be applied to various fields suitable for the invention. Other modifications can be readily made by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, the invention is not limited to the specific details and examples shown and described herein.

Claims

1. A safety relay contact pressure electronic force measuring circuit, characterized in that, include: A contact status monitoring circuit, one end of which is connected to a relay contact to capture the relay contact status; The pressure detection circuit has one end connected to the other end of the contact status monitoring circuit via a UART1 serial port for bidirectional communication. The signal conditioning circuit has one end connected to the contact status monitoring circuit via relay U8, and the other end directly connected to the analog signal acquisition pin of the pressure detection circuit. The contact status monitoring circuit has a built-in second central processing unit (CPU2), and the pressure detection circuit has a built-in first central processing unit (CPU1), which together form a dual-CPU control architecture. The pressure detection circuit integrates an attitude sensor, and the force angle signal collected by the attitude sensor and the pressure analog signal output by the signal conditioning circuit are sent together to CPU1; The signal conditioning circuit, contact status monitoring circuit, and pressure detection circuit are all integrated inside the whole machine, without any external independent force measuring instruments; When the contact status monitoring circuit detects a transient level signal indicating contact disconnection, the hardware synchronously triggers the pressure detection circuit to collect the peak pressure at the moment of contact disconnection.

2. The electronic force measuring circuit for safety relay contact pressure as described in claim 1, characterized in that, The signal conditioning circuit includes a micro-force sensor, a filter circuit, and an amplification conditioning circuit; One end of the micro-force sensor is connected to the contact status monitoring circuit via the relay, and the other end is connected to the input terminal of the filter circuit; The output terminal of the filter circuit is connected to the input terminal of the amplification and conditioning circuit, and the output terminal of the amplification and conditioning circuit outputs a contact pressure signal. The filtering circuit is a symmetrical differential RC filter topology, consisting of resistors R20 and R21, and capacitors C29, C30, and C31, which is suitable for the acquisition of weak differential force signals of 0~2500mN in the strong electromagnetic interference environment of railway stations.

3. The electronic force measuring circuit for safety relay contact pressure as described in claim 2, characterized in that, The filter circuit includes resistor R20, resistor R21, capacitor C31, capacitor C29, and capacitor C30; The input terminal of the resistor R20 is connected to one output terminal of the micro-force sensor, and the output terminal of the resistor R20 is connected between the capacitor C31 and the capacitor C29. The input terminal of the resistor R21 is connected to the other output terminal of the micro-force sensor, and the output terminal of the resistor R21 is connected between the capacitor C29 and the capacitor C30. The pressure FS analog signal output by the amplification and conditioning circuit is synchronously sent to CPU1 along with the two angle signals S1 and S2 output by the attitude sensor to participate in the Kalman filter truth value calculation.

4. The electronic force-measuring circuit for safety relay contact pressure as described in claim 2, characterized in that, The amplification and conditioning circuit includes an operational amplifier U3; The differential input terminals of the operational amplifier U3 are connected to the differential output terminals of the micro-force sensor FS+ and FS- via R20 and R21, respectively. The operational amplifier U3 outputs a contact pressure signal.

5. The electronic force measuring circuit for safety relay contact pressure as described in claim 1, characterized in that, The pressure detection circuit includes a first central processing unit (CPU1), an attitude sensor, a display, an interface chip, and multiple peripheral circuits. The attitude sensor is connected to the first central processing unit CPU1; The display and interface chip are respectively connected to the first central processing unit CPU1 via peripheral circuits. The pressure analog signal output by the signal conditioning circuit is connected to the AD acquisition pin of the first central processing unit CPU1. After analog-to-digital conversion, it is combined with the attitude angle data to complete Kalman filtering and quantized and calibrated to a standard force value of 0~2500mN. The first central processing unit (CPU1) drives the local display to show the instantaneous pressure value and transmits the corrected precise force value to the contact status monitoring circuit via the interface chip.

6. The electronic force-measuring circuit for safety relay contact pressure as described in claim 5, characterized in that, The interface chip communicates bidirectionally with the second central processing unit (CPU2) inside the contact status monitoring circuit via the UART1 serial port. After the correction force value output by the first central processing unit (CPU1) is transmitted to the second central processing unit (CPU2), the second central processing unit (CPU2) binds the force value data with the corresponding contact number to generate a structured test data packet.

7. The electronic force measuring circuit for safety relay contact pressure as described in claim 5, characterized in that, The display is an OLED screen, which is located locally in the pressure detection circuit and is used to display the pressure peak at the moment the contact is disconnected in real time. The whole machine is paired with a host PC to form a two-layer data processing architecture of local real-time verification and background batch data storage and archiving.

8. The electronic force measuring circuit for safety relay contact pressure as described in claim 1, characterized in that, The contact status monitoring circuit includes a second central processing unit (CPU2), which is configured with 16 independent acquisition pins and is paired with an optocoupler isolation relay U8 to achieve strong and weak current isolation. The 16 pins are divided into 8 front contact acquisition channels and 8 rear contact acquisition channels, which can simultaneously monitor the two working conditions of the relay being picked up and dropped. When any contact level changes, a hardware interrupt is directly triggered on the second central processing unit (CPU2), locking the action contact number and triggering pressure acquisition.

9. The electronic force measuring circuit for safety relay contact pressure as described in claim 1, characterized in that, It also includes a host computer, which is connected to the contact status monitoring circuit via an RS232 bus.

10. An electronic force measuring device, characterized in that, include: The electronic force measuring circuit for safety relay contact pressure as described in any one of claims 1 to 9.

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