Strain measurement device based on wireless transmission

Abstract

The utility model discloses a strain measurement device based on wireless transmission, belongs to the technical field of strain measurement, and solves the problems of high measurement cost and high measurement difficulty of an existing stress measurement device. Comprising a strain gauge, a data acquisition device, a Bluetooth transmitting device, a Bluetooth receiving device, a power supply, a voltage regulation device and a PC terminal, the output end of the strain gauge is connected with the input end of the data acquisition device, the output end of the data acquisition device is connected with the input end of the Bluetooth transmitting device, the transmitting end of the Bluetooth transmitting device and the receiving end of the Bluetooth receiving device carry out data transmission through Bluetooth signals, and the Bluetooth receiving device is connected with the PC terminal through a USB interface. According to the utility model, the local stress condition in the elastic deformation range of the workpiece can be calculated by measuring the dependent variable of the strain gauge and combining the Young's elastic modulus of the workpiece, and the measuring device is simple in structure, low in design cost and low in dependent variable measuring difficulty.

Description

Technical Field

[0001] The utility model belongs to the technical field of strain measurement and relates to a strain measurement device based on wireless transmission. Background Art

[0002] Thermal power plants include generators, boilers, combustion systems, transmission lines, lifting systems, and other components, all of which require stress analysis. As one of the core equipment in a power plant, the generator is responsible for converting mechanical energy into electrical energy. During the power generation process, the generator is subjected to stresses such as high-speed rotation and high temperature, requiring stress analysis to ensure its reliability and safety. The boiler, as the thermal energy conversion equipment of the power plant, is responsible for converting the heat energy generated by fuel combustion into steam. The boiler's working environment is complex, with stresses such as high temperature and high pressure. Stress analysis is required to assess its stress conditions and load-bearing capacity. The combustion system, including the combustion chamber, burner, and other devices, is responsible for mixing and burning fuel and air to generate heat energy. During the combustion process, stresses such as high temperature, high pressure, and high-speed airflow are generated, requiring stress analysis of the combustion system to ensure its structural stability and durability. The steam turbine is the main power unit of the power plant, used to convert steam energy into mechanical energy. During operation, the steam turbine is subjected to stresses such as high-speed rotation and high temperature. Stress analysis is also required to assess its stress conditions and structural safety. Transmission lines and transmission towers are important facilities that transmit the electricity generated by the power plant to users. They must withstand stresses such as current load, wind pressure, and temperature changes. Stress analysis is also required to ensure their stable operation and safety and reliability.

[0003] However, there are few existing devices that can measure stress, and most of them are macroscopic overall measurements, which have high measurement costs and great measurement difficulty. Therefore, there is an urgent need for a strain measurement device that can achieve low design cost, miniaturized structure, and low measurement difficulty to meet actual needs. Utility Model Content

[0004] The technical solution of the utility model is used to solve the problems of high measurement cost and great measurement difficulty of existing stress measurement devices.

[0005] The utility model solves the above technical problems through the following technical solutions:

[0006] A strain measurement device based on wireless transmission includes a strain gauge, a data acquisition device, a Bluetooth transmitter, a Bluetooth receiver, a power supply, a voltage regulator, and a PC terminal. The output end of the strain gauge is connected to the input end of the data acquisition device, the output end of the data acquisition device is connected to the input end of the Bluetooth transmitter, the transmitter end of the Bluetooth transmitter and the receiver end of the Bluetooth receiver transmit data via Bluetooth signals, and the Bluetooth receiver is connected to the PC terminal via a USB interface. The output end of the voltage regulator is respectively connected to the power supply interface of the data acquisition device and the power supply interface of the Bluetooth transmitter, and the input end of the voltage regulator is connected to the power supply via a USB interface. The data acquisition device includes a main control module, an analog-to-digital conversion module, and a power supply voltage stabilization module.

[0007] Furthermore, the main control module includes a chip U1, a diode D3, a resistor R5, a resistor R6, and a reset resistor RESET; the 8 # Pin 9 # After the pins are connected together, they are connected to the diode D3. The other end of the diode D3 is connected to the chip U2. The 10 # pin is grounded, the chip U1’s 12 # Pin is connected with chip U2, the 11 of chip U1 # The pin is connected to one end of the resistor R6, and the 14 # The pin is connected to one end of the resistor R5, and the 19 # The pin is connected to one end of the reset resistor RESET, and the other end of the reset resistor RESET is grounded. The 14 # The pin is used as the receiving end of the data acquisition device, and the 11 pin of the chip U1 # The pin serves as the transmitting end of the data acquisition device, and is used to receive and send data from the Bluetooth sending module.

[0008] Furthermore, the model of the chip U1 is STC8H8K64U.

[0009] Furthermore, the analog-to-digital conversion module includes a chip U2, capacitors C6-8, resistors R7-13, and a diode D4; the positive electrode of the input end of the strain gauge is connected in series with resistor R7 and diode D4, the non-series end of the diode D4 is connected to the positive electrode of the power supply of the data acquisition device 2, one end of the capacitor C6 is connected to the common connection point of the resistor R7 and the diode D4, and the other end of the capacitor C6 is grounded; the resistors R11, R12, and R13 are connected in series in sequence, the non-series end of the resistor R11 is connected to the positive electrode of the input end of the strain gauge, and the non-series end of the resistor R13 is connected to the negative electrode of the input end of the strain gauge; one end of the resistor R8 is connected to the common connection point of the resistor R12 and the resistor R13, and the other end of the resistor R8 is grounded; 1 of the chip U2 # The pin is connected to one end of the capacitor C7, and the other end of the capacitor C7 is grounded. The 2 # The pin is grounded, one end of the capacitor C8 is connected to the 3 # The other end of capacitor C8 is connected to the 4 pin of chip U2. # Pin connection, one end of the resistor R9 is connected to the negative input terminal of the strain gauge, and the other end of the resistor R9 is connected to the 3 pin of the chip U2. # Pin connection, one end of the resistor R10 is connected to the negative input terminal of the strain gauge, and the other end of the resistor R10 is connected to the 4 # Pin connection, the chip U2 5 # Pin 6 # Pin connection, chip U2 8 # Pin 7 is connected to diode D3, chip U2 # Pin 12 of chip U1 # Pin connections.

[0010] Furthermore, the model of the chip U2 is HX710A.

[0011] Furthermore, the power supply voltage stabilization module includes chips U3-4, resistors R1-4, capacitors C1-5, and diodes D1-2; the chip U3 has 1 # The pin is connected to the other end of resistor R5, and the 2 # Pin 3 # Pin connection, chip U3 4 # The pin is connected to the other end of resistor R6, and the 5 # The pin is grounded, the resistor R3 is connected in series with the resistor R4, and the non-series end of the resistor R3 is connected to the 6 pin of the chip U3. # Pin connection, the non-series end of resistor R4 is connected to the 7 pin of chip U3 # Pin connection, chip U3 8 #The pin is connected to one end of capacitor C3. After capacitor C3 and capacitor C4 are connected in parallel, the other end of capacitor C3 is connected to capacitor C2 and capacitor C1 respectively. The other end of capacitor C1 is connected to 1 pin of chip U4. # The other end of capacitor C2 is connected to the 2 pin of chip U4. # Pin connection, chip U4 1 # The pin is grounded; the capacitor C5, diode D2, resistor R2, and resistor R1 are connected in series in sequence, and the non-series connection of the capacitor C5 is connected to the 2 # The non-series end of the resistor R1 is connected to one end of the diode D1, and the other end of the diode D1 is connected to the common point of the capacitor C5 and the diode D2. The non-series end of the resistor R1 serves as the positive power supply interface of the data acquisition device. The 2 # The pin serves as the negative power supply interface of the data acquisition device.

[0012] Furthermore, the model of the chip U3 is BL3085, and the model of the chip U4 is HT7550-1.

[0013] Furthermore, the input voltage of the voltage regulating device is 5V, and the output voltage range is 1-24V.

[0014] Furthermore, the strain gauge is arranged on the workpiece to be measured.

[0015] The advantages of the present invention are: (1) the present invention can calculate the local stress conditions within the elastic deformation range of the workpiece by measuring the strain of the strain gauge and combining it with the Young's elastic modulus of the workpiece. At the same time, the measuring device has a simple structure, low design cost, and low difficulty in measuring the strain.

[0016] (2) The present invention converts the analog data signal obtained by the strain gauge measurement into a digital signal by modularizing the internal components of the data acquisition device, and transmits the digital signal to the Bluetooth sending module. The Bluetooth module is used for wireless data transmission to avoid various faults in the physical connection.

[0017] (3) The present invention can adjust the power supply voltage of the data acquisition device and the Bluetooth transmitting device according to actual needs. At the same time, the power supply voltage stabilizing module provided in the data acquisition device can stabilize the voltage input of the data acquisition device when adjusting the voltage, protect the circuit, and improve the power supply quality of the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a structural diagram of a strain measurement device based on wireless transmission according to an embodiment of the present utility model;

[0019] Figure 2 This is a diagram of the internal circuit structure of the data acquisition device according to an embodiment of the present utility model;

[0020] Figure 3 This is a pin diagram of the chip U1 according to an embodiment of the present invention;

[0021] Figure 4 This is a pin diagram of the chip U2 according to an embodiment of the present invention;

[0022] Figure 5 This is a pin diagram of the chip U3 according to an embodiment of the present invention;

[0023] Figure 6 This is a pin diagram of the chip U4 according to an embodiment of the present invention;

[0024] Description of the accompanying drawings: 1. Strain gauge; 2. Data acquisition device; 3. Bluetooth transmitter; 4. Bluetooth receiver; 5. Power supply; 6. Voltage regulator; 7. PC terminal. DETAILED DESCRIPTION

[0025] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the embodiments described are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0026] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and specific embodiments:

[0027] Example 1

[0028] like Figure 1 As shown, specifically, a strain measurement device based on wireless transmission is disclosed, including a strain gauge 1, a data acquisition device 2, a Bluetooth transmitting device 3, a Bluetooth receiving device 4, a power supply 5, a voltage regulating device 6 and a PC terminal 7; the output end of the strain gauge 1 is connected to the input end of the data acquisition device 2, the output end of the data acquisition device 2 is connected to the input end of the Bluetooth transmitting device 3, the transmitting end of the Bluetooth transmitting device 3 and the receiving end of the Bluetooth receiving device 4 transmit data via Bluetooth signals, and the Bluetooth receiving device 4 is connected to the PC terminal 7 via a USB interface;

[0029] The output end of the voltage regulating device 6 is connected to the power supply 5 interface of the data acquisition device 2 and the power supply 5 interface of the Bluetooth sending device 3 respectively, and the input end of the voltage regulating device 6 is connected to the power supply 5 through the USB interface.

[0030] The data acquisition device 2 is a data acquisition module composed of capacitors, resistors, and chips. It amplifies the data and transmits the amplified data to the computer via Bluetooth signals.

[0031] like Figure 2-6 As shown, the data acquisition device 2 includes a main control module, an analog-to-digital conversion module, and a power supply voltage stabilization module; the main control module includes a chip U1, a diode D3, a resistor R5, a resistor R6, and a reset resistor RESET; the 8 # Pin 9 # After the pins are connected together, they are connected to the diode D3, and the other end of the diode D3 is connected to the chip U2; the 10 # Pin is grounded; the chip U1 12 # The pin is connected to the chip U2; the 11 pin of the chip U1 # The pin is connected to one end of the resistor R6; the 14 # The pin is connected to one end of the resistor R5; the 19 # The pin is connected to one end of the reset resistor RESET, and the other end of the reset resistor RESET is grounded; the 14 # The pin is used as the receiving end (RX end) of the data acquisition device 2, and the 11 # The pin serves as the transmitting end (TX end) of the data acquisition device 2, and is used to receive and send data from the Bluetooth transmitting module. Specifically, the model of the chip U1 is STC8H8K64U.

[0032] The analog-to-digital conversion module includes a chip U2, capacitors C6-8, resistors R7-13, and a diode D4; the positive electrode of the input end of the strain gauge is connected in series with resistor R7 and diode D4, and the non-series end of the diode D4 is connected to the positive electrode of the power supply of the data acquisition device 22. One end of the capacitor C6 is connected to the common connection point of the resistor R7 and the diode D4, and the other end of the capacitor C6 is grounded; the resistors R11, R12, and R13 are connected in series in sequence, the non-series end of the resistor R11 is connected to the positive electrode of the input end of the strain gauge, and the non-series end of the resistor R13 is connected to the negative electrode of the input end of the strain gauge; one end of the resistor R8 is connected to the common connection point of the resistors R12 and R13, and the other end of the resistor R8 is grounded;

[0033] 1 of the chip U2 # The pin is connected to one end of the capacitor C7, and the other end of the capacitor C7 is grounded. The 2 # The pin is grounded, one end of the capacitor C8 is connected to the 3 # The other end of capacitor C8 is connected to the 4 pin of chip U2. #Pin connection, one end of the resistor R9 is connected to the negative input terminal of the strain gauge, and the other end of the resistor R9 is connected to the 3 pin of the chip U2. # Pin connection, one end of the resistor R10 is connected to the negative input terminal of the strain gauge, and the other end of the resistor R10 is connected to the 4 # Pin connection, the chip U2 5 # Pin 6 # Pin connection, chip U2 8 # Pin 7 is connected to diode D3, chip U2 # Pin 12 of chip U1 # Pin connection; specifically, the chip U2 model is HX710A, which is an analog-to-digital conversion (ADC) chip for converting the analog signal measured by the strain gauge into a digital signal.

[0034] The power supply voltage stabilization module includes chips U3-4, resistors R1-4, capacitors C1-5, and diodes D1-2; the chip U3 # The pin is connected to the other end of resistor R5, and the 2 # Pin 3 # Pin connection, chip U3 4 # The pin is connected to the other end of resistor R6, and the 5 # The pin is grounded, the resistor R3 is connected in series with the resistor R4, and the non-series end of the resistor R3 is connected to the 6 pin of the chip U3. # Pin connection, the non-series end of resistor R4 is connected to the 7 pin of chip U3 # Pin connection, chip U3 8 # The pin is connected to one end of capacitor C3. After capacitor C3 and capacitor C4 are connected in parallel, the other end of capacitor C3 is connected to capacitor C2 and capacitor C1 respectively. The other end of capacitor C1 is connected to 1 pin of chip U4. # The other end of capacitor C2 is connected to the 2 pin of chip U4. # Pin connection, chip U4 1 # The pin is grounded; the capacitor C5, diode D2, resistor R2, and resistor R1 are connected in series in sequence, and the non-series connection of the capacitor C5 is connected to the 2 # The non-series end of the resistor R1 is connected to one end of the diode D1, and the other end of the diode D1 is connected to the common point of the capacitor C5 and the diode D2. The non-series end of the resistor R1 serves as the positive power supply interface of the data acquisition device 2. The 2 # The pin serves as the negative power supply interface of the data acquisition device 2; specifically, the model of the chip U3 is BL3085, and the model of the chip U4 is HT7550-1, which are used to stabilize the voltage input, protect the circuit, and improve the circuit power quality.

[0035] The power supply 5 can use a power bank to provide a 5V input voltage to the voltage regulating device 6; the voltage regulating device 6 is a DC-DC converter with an input voltage of 5V and an output voltage range of 1-24V, which can adjust the power supply voltage of the data acquisition device 2 and the Bluetooth sending device 3 according to actual needs.

[0036] The Bluetooth receiving device 4 is plugged into the PC terminal 7 via a USB interface and powered by the PC. In this embodiment, the Bluetooth transmitting device 3 and the Bluetooth receiving device 4 can use existing technologies to achieve short-range wireless transmission, and can simply send the signal collected by the strain gauge 1 to the PC terminal 7.

[0037] The strain gauge 1 is a component used to measure strain, consisting of a sensitive grid. The primary materials are copper and coated with polyvinyl chloride. The strain gauge 1 is mounted on the workpiece to be measured. In this embodiment, the strain gauge 1 can be attached to the workpiece surface using quick-drying adhesive.

[0038] Working Principle: When the equipment is running, the workpiece is subjected to force and strain. By measuring the resistance value of the strain gauge 1 on the surface of the workpiece, the amount of strain on the workpiece can be known. By looking up the value, the Young's modulus of elasticity of the workpiece can be obtained, and the local force on the workpiece within the elastic deformation range can be calculated. The load calculation expression for the strain generated by the force on the workpiece is as follows:

[0039] σ=E×ε

[0040] Where: σ is the load, E is the Young's elastic modulus, and ε is the strain.

[0041] The data acquisition device 2 can convert the electrical signal into a digital signal and transmit it to the Bluetooth transmitter 3. The Bluetooth transmitter 3 sends the digital signal to the Bluetooth receiver 4 of the PC terminal 7. The Bluetooth receiver 4 is connected to the PC via a USB interface, analyzes the digital signal, and displays the strain on the PC terminal 7. The data of the Young's modulus of common metals at room temperature is shown in Table 1:

[0042] Table 1 Data table of Young's elastic modulus of common metals at room temperature

[0043] Common metals Young's modulus of elasticity at room temperature (GPa) Tungsten 400-420 chromium 200-230 nickel 200-220 Iron (steel) 190-210 copper 110-128 aluminum 69-78 magnesium 45-50

[0044] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A strain measurement device based on wireless transmission, characterized in that: The device comprises a strain gauge, a data acquisition device, a Bluetooth transmitter, a Bluetooth receiver, a power supply, a voltage regulator, and a PC terminal; the output end of the strain gauge is connected to the input end of the data acquisition device, the output end of the data acquisition device is connected to the input end of the Bluetooth transmitter, the transmitter end of the Bluetooth transmitter and the receiver end of the Bluetooth receiver perform data transmission via Bluetooth signals, and the Bluetooth receiver is connected to the PC terminal via a USB interface; The output end of the voltage regulating device is connected to the power interface of the data acquisition device and the power interface of the Bluetooth sending device respectively, and the input end of the voltage regulating device is connected to the power supply through the USB interface; The data acquisition device includes a main control module, an analog-to-digital conversion module, and a power supply voltage stabilization module.

2. The strain measurement device based on wireless transmission according to claim 1, characterized in that: The main control module includes a chip U1, a diode D3, a resistor R5, a resistor R6, and a reset resistor RESET; the 8 # Pin 9 # After the pins are connected together, they are connected to the diode D3. The other end of the diode D3 is connected to the chip U2. The 10 # pin is grounded, the chip U1’s 12 # Pin is connected with chip U2, the 11 of chip U1 # The pin is connected to one end of the resistor R6, and the 14 # The pin is connected to one end of the resistor R5, and the 19 # The pin is connected to one end of the reset resistor RESET, and the other end of the reset resistor RESET is grounded. The 14 # The pin is used as the receiving end of the data acquisition device, and the 11 pin of the chip U1 # The pin serves as the transmitting end of the data acquisition device, and is used to receive and send data from the Bluetooth sending module.

3. The strain measurement device based on wireless transmission according to claim 2, characterized in that: The model of the chip U1 is STC8H8K64U.

4. The strain measurement device based on wireless transmission according to claim 2, characterized in that: The analog-to-digital conversion module includes a chip U2, capacitors C6-8, resistors R7-13, and a diode D4; the positive electrode of the input end of the strain gauge is connected in series with the resistor R7 and the diode D4, the non-series end of the diode D4 is connected to the positive electrode of the power supply of the data acquisition device (2), one end of the capacitor C6 is connected to the common connection point of the resistor R7 and the diode D4, and the other end of the capacitor C6 is grounded; the resistors R11, R12, and R13 are connected in series in sequence, the non-series end of the resistor R11 is connected to the positive electrode of the input end of the strain gauge, and the non-series end of the resistor R13 is connected to the negative electrode of the input end of the strain gauge; one end of the resistor R8 is connected to the common connection point of the resistors R12 and R13, and the other end of the resistor R8 is grounded; 1 of the chip U2 # The pin is connected to one end of the capacitor C7, and the other end of the capacitor C7 is grounded. The 2 # The pin is grounded, one end of the capacitor C8 is connected to the 3 # The other end of capacitor C8 is connected to the 4 pin of chip U2. # Pin connection, one end of the resistor R9 is connected to the negative input terminal of the strain gauge, and the other end of the resistor R9 is connected to the 3 pin of the chip U2. # Pin connection, one end of the resistor R10 is connected to the negative input terminal of the strain gauge, and the other end of the resistor R10 is connected to the 4 # Pin connection, the chip U2 5 # Pin 6 # Pin connection, chip U2 8 # Pin 7 is connected to diode D3, chip U2 # Pin 12 of chip U1 # Pin connections.

5. The strain measurement device based on wireless transmission according to claim 4, characterized in that: The model of the chip U2 is HX710A.

6. The strain measurement device based on wireless transmission according to claim 4, characterized in that: The power supply voltage stabilization module includes chips U3-4, resistors R1-4, capacitors C1-5, and diodes D1-2; the chip U3 # The pin is connected to the other end of resistor R5, and the 2 # Pin 3 # Pin connection, chip U3 4 # The pin is connected to the other end of resistor R6, and the 5 # The pin is grounded, the resistor R3 is connected in series with the resistor R4, and the non-series end of the resistor R3 is connected to the 6 pin of the chip U3. # Pin connection, the non-series end of resistor R4 is connected to the 7 pin of chip U3 # Pin connection, chip U3 8 # The pin is connected to one end of capacitor C3. After capacitor C3 and capacitor C4 are connected in parallel, the other end of capacitor C3 is connected to capacitor C2 and capacitor C1 respectively. The other end of capacitor C1 is connected to 1 pin of chip U4. # The other end of capacitor C2 is connected to the 2 pin of chip U4. # Pin connection, chip U4 1 # The pin is grounded; the capacitor C5, diode D2, resistor R2, and resistor R1 are connected in series in sequence, and the non-series connection of the capacitor C5 is connected to the 2 # The non-series end of the resistor R1 is connected to one end of the diode D1, and the other end of the diode D1 is connected to the common point of the capacitor C5 and the diode D2. The non-series end of the resistor R1 serves as the positive power supply interface of the data acquisition device. The 2 # The pin serves as the negative power supply interface of the data acquisition device.

7. The strain measurement device based on wireless transmission according to claim 6, characterized in that: The model of the chip U3 is BL3085, and the model of the chip U4 is HT7550-1.

8. The strain measurement device based on wireless transmission according to claim 1, characterized in that: The input voltage of the voltage regulating device is 5V, and the output voltage range is 1-24V.

9. The strain measurement device based on wireless transmission according to claim 1, characterized in that: The strain gauge is arranged on the workpiece to be measured.

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