CN103706927A - Multifunctional welding system of underwater welding robot - Google Patents

Abstract

The invention provides a multifunctional welding system for an underwater welding robot, which includes an arc welding robot interface, a digital arc welding inverter power supply, a submersible wire feeder, a special welding torch for robots, a miniature drainage cover, a compressed gas device and a protective gas device The arc welding robot interface, the digital arc welding inverter power supply, the submersible wire feeder and the robot special welding torch are connected in sequence; The gas device is connected; the special welding torch for the robot is installed on the robot and connected to the miniature drainage cover, one end of which is connected to the arc load; the compressed gas device is connected to the miniature drainage cover, and the protective gas device is connected to the submersible wire feeder. The welding system of the invention can automatically adapt to the characteristics of the underwater welding arc during the welding process, establish a stable welding power source-underwater arc system, and realize high-quality underwater robot welding.

Description

Multifunctional Welding System for Underwater Welding Robot

technical field

The invention relates to welding technology and equipment technology, and more specifically, relates to a multifunctional welding system of an underwater welding robot.

Background technique

With the rapid development of the national economy and the urgent need of energy strategy, marine engineering is constantly advancing to the deep sea. As an important technology in the field of ocean engineering, underwater welding is receiving more and more attention. From the installation and construction of offshore oil and gas platforms to the laying and maintenance of submarine pipelines, from sea salvage and rescue work to emergency repairs of large ships, underwater welding can be seen everywhere. Research on underwater welding robots has promoted the development of the underwater welding industry. Compared with the previous manual underwater welding, underwater welding robots have higher welding efficiency, more reliable welding engineering quality, and lower welding costs. basis for development.

Due to the complexity and uncertainty of the underwater environment, no welding robot is currently engaged in complete underwater welding activities. There are many factors that affect the quality of underwater welds, but whether the arc burns stably during welding is the basic requirement. Compared with the usual welding arc, the arc in the water environment has poor combustion stability due to the influence of water pressure and other factors. From the perspective of mechanism, in order to make the underwater arc burn stably, there must be a corresponding power supply to match it, and a stable power supply-arc system can be established. Judging from relevant application and research reports at home and abroad, underwater welding usually uses land-based general-purpose welding systems directly, or performs structural fine-tuning on the basis of general-purpose welding systems. That is to say, the adjustment of the underwater welding process can only rely on the performance of the existing general welding system, that is, the process can only be adapted to the power supply, and the power supply cannot be adapted to the underwater welding process. Therefore, it is difficult for the existing power source-arc system to make the most effective control of the process according to the particularity of the underwater arc. It is very difficult to use land-based welding power sources for underwater welding to achieve stable arc combustion and good welding results. of. The inverter welding machine has many advantages such as energy saving, material saving, and good dynamic performance, which is very conducive to the realization of precise control. Combining it with advanced digital control technology can fundamentally improve the performance index of the welding system and make the control more flexible , good scalability. When the hardware resources are reasonably allocated, the expected effect can be obtained only by replacing the corresponding control strategy or modifying the corresponding control software according to different application requirements. This lays the foundation for the development of a special welding system adapted to the characteristics of the underwater welding arc.

Contents of the invention

The purpose of the present invention is to overcome the shortcomings and deficiencies in the prior art, to provide a multifunctional welding system for underwater welding robots, which can automatically adapt to the characteristics of the underwater welding arc during the welding process, and to establish a stable welding power supply-underwater arc system , to achieve high-quality underwater robot welding.

In order to achieve the above object, the present invention is achieved through the following technical solutions: a multifunctional welding system for an underwater welding robot, which is characterized in that it includes an arc welding robot interface, a digital arc welding inverter power supply, a submersible wire feeder, and a special welding system for robots. Welding torch, micro drainage cover, compressed gas device and shielding gas device; the arc welding robot interface, digital arc welding inverter power supply, submersible wire feeder and robot-specific welding torch are connected in sequence; the arc welding robot interface is also connected with The robot, the submersible wire feeder, the compressed gas device and the protective gas device are connected; the special welding torch for the robot is installed on the robot, and is also connected with the miniature drainage cover and the arc load; the compressed gas device is connected with the miniature drainage cover, The shielding gas device is connected with the submersible wire feeder.

In the above scheme, the robot-specific welding torch of the welding system of the present invention is installed on the body of the welding robot; and the arc welding robot interface is directly connected with the robot through the CAN bus; The hood is directly installed on the end of the special welding torch for the robot; the compressed gas device adopts an air compressor system, which is directly connected with the miniature drainage hood to provide compressed air for the micro drainage hood to discharge the water in the welding arc area; the special welding torch for the robot is directly connected to the The submersible wire feeder is connected, and the welding wire is sent to the welding area through the special welding torch of the robot; the shielding gas device is an argon-rich or pure argon gas supply device, which is directly connected to the submersible wire feeder, and sent to the welding arc area through the special welding torch of the robot , to achieve reliable protection.

The digital arc welding inverter power supply includes a main circuit one and a control circuit one connected to the main circuit one; the main circuit one is composed of a rectification filter circuit, an inverter bridge, an intermediate frequency transformer and a fast rectification filter circuit in sequence; The rectification and filtering circuit is electrically connected to the three-phase AC input power supply, and the fast rectification and filtering circuit is connected to the second arc load.

The inverter bridge of the main circuit one adopts a hard-switching commutation mode, or a full-bridge high-frequency inverter topology working in a soft-switching mode.

The control circuit one includes a power supply module electrically connected to the three-phase AC input power supply and used to provide electric energy to the control circuit one, a minimum system, and an action detection module connected to the minimum system, an overheat detection module, an overvoltage and undervoltage detection module, A high-frequency drive module, a peak current detection module, a current feedback circuit, a digital panel, a CAN interface circuit and a relay module; wherein, the overvoltage and undervoltage detection module is electrically connected to a three-phase AC input power supply.

The high-frequency drive module is connected with the inverter bridge of the main circuit one, the peak current detection module is connected with the intermediate frequency transformer of the main circuit one, and the current feedback circuit is connected with the fast rectification filter circuit of the main circuit one; the minimum of the control circuit one The system has two protection modes: pulse-by-pulse current limiting protection and direct shutdown protection.

The arc welding robot interface includes a power supply module for providing electric energy, an ARM controller, a feedback module connected to the ARM controller, a relay module, a communication expansion module, an information interaction module provided with a digital controller, and an analog output module; Wherein, the communication expansion module is connected to the CAN interface circuit of the control circuit 1 through the CAN bus; the arc welding robot interface is respectively connected to the compressed gas device and the protective gas device. The gas device is connected to control the start and stop of the compressed gas device and the protective gas device; the feedback module is connected to the compressed gas device and the protective gas device respectively, and is used to collect the information of the compressed gas device and the protective gas device. The information interaction module in the interface of the arc welding robot of the present invention adopts a composite visualization system structure of "STM32F407ZGT6+RA8875+TFT-LCD+rotary encoder+button".

The submersible wire feeder is provided with a sealing cover, and is composed of a wire feeding drive circuit, a wire feeding motor, a pinch wheel and a wire reel connected; the wire feed drive circuit, wire feed motor, pinch wheel and wire reel are all installed In the sealing cover; one end of the special welding torch for the robot is fixed on the sealing cover of the submersible wire feeder; the protective gas device is connected with the sealing cover of the submersible wire feeder. The submersible wire feeder of the present invention has three wire feeding modes: constant speed wire feeding, variable speed wire feeding and pulse wire feeding.

The wire feeding driving circuit includes a main circuit 2 and a control circuit 2 connected with the main circuit 2; the control circuit 2 is composed of an MCU controller and a peripheral circuit; the main circuit 2 includes rectification and filtering circuits, BUCK A voltage stabilizing circuit, a phase commutation circuit and a chopper circuit; one end of the chopper circuit is connected to a wire-feeding motor, and the wire-feeding motor is connected to the ADC port of the MCU controller, and the voltage is fed back to the control circuit two; the MCU controller The PWM port of the MCU controller is connected to the chopper circuit of the main circuit two through the IR2110 driver one to realize the speed regulation of the motor; the TIMER port of the MCU controller is connected to the commutation circuit of the main circuit two through the IR2110 driver two to realize the motor Forward and reverse control; the CAN port of the MCU controller is respectively connected to the communication expansion module of the arc welding robot interface and the CAN interface circuit of the digital arc welding inverter power supply through the CAN bus.

The ARM microcontroller in the arc welding robot interface and the digital controller of the information interaction module, the minimum system and digital panel in the digital arc welding inverter power supply control circuit and the MCU controller of the submersible wire feeder are all composed of the model STM32F405RGT6 Microprocessor, power supply circuit, reset circuit, crystal oscillator circuit, JTAG interface, miniUSB chip and peripheral circuit connections. The microprocessor of the present invention all adopts the minimum system of the Cortex-M4 kernel STM32F405RGT6 of ST Company main frequency up to 168MHz.

In order to better realize the present invention, the micro-drain cover is a convergent shrinking nozzle structure. The miniature drainage cover of the present invention adopts a convergent partial drainage cover made of 304 stainless steel, and the drainage cover can meet the requirements of the all-position local dry welding process for the drainage of the welding area.

The invention is a multi-functional welding system for an underwater welding robot. The interface of the arc welding robot receives parameters and work instructions sent by the robot. When welding, the arc welding robot interface first turns on the compressed gas device, feeds compressed air into the miniature drainage cover, and drains the water in the elongated area of the welding wire at the front end of the robot's special welding torch; then starts the protective gas device and sends it to the submersible wire feeder , while supplying power to the digital arc welding inverter power supply and submersible wire feeder, the arc welding robot interface sends the preset welding current, voltage and other parameters to the digital arc welding inverter power supply through the CAN bus, and sends the wire feeding speed parameters and wire feeding Mode commands are sent to the submersible wire feeder. When the arc welding robot sends a welding command, the shielding gas is sent to the front end area of the welding wire through the submersible wire feeder and the robot's special welding torch, and the no-load voltage of the digital arc welding inverter power supply is also applied to the welding wire. The arc is ignited by wire; after the arc is successfully ignited, it enters the normal welding stage. After the arc welding robot interface receives the welding end instruction sent by the robot, it controls the arc welding power supply through the bus to enter the arc extinguishing control stage, the current gradually decays to the arc extinguishing, and the shielding gas device will lag behind the gas supply to protect the weld area; after welding, according to the robot The command sent to shut down the underwater welding system. During the whole welding process, the arc welding robot interface receives commands from the robot to start the system, adjust the voltage, adjust the current, feed gas, feed wire, strike the arc, shut down the system, and control the actions of the compressed gas device and the shielding gas device respectively. The communication sends instructions to the digital arc welding inverter power supply and submersible wire feeder; on the other hand, it also needs to receive real-time fault information such as overvoltage, undervoltage, overheating and other fault information sent by the digital arc welding inverter power supply, as well as the status information of successful arc ignition. It is also necessary to receive real-time fault information such as no welding wire and insufficient air pressure sent by the submersible wire feeder, and at the same time realize the detection of faults such as sticking wire, arc extinguishing, and contact nozzle. In addition, the arc welding robot interface also needs to send corresponding fault information to the robot, and also needs to display various faults and actual status information of the system locally. The submersible wire feeder receives the wire feeding command sent by the arc welding robot interface to perform real-time closed-loop control of the wire feeding speed, and detects the faults such as wire shortage (no welding wire) and insufficient air pressure in real time, and transmits the information to the Arc welding robot interface. The digital arc welding inverter power supply receives control signals such as start, stop, voltage adjustment, and current adjustment sent by the arc welding robot interface through the CAN bus, and also detects fault information such as overvoltage, undervoltage, and overheating in real time, and passes the information through The CAN bus is passed to the arc welding robot interface.

Compared with the prior art, the present invention has the following advantages and beneficial effects:

1. The underwater welding robot multifunctional welding system of the present invention realizes the full digital control of the robot underwater welding system. The system structure is more flexible, the operation is intuitive, the maintenance is convenient, and it has better scalability and portability.

2. The multi-functional welding system of the underwater welding robot of the present invention adopts a fully digital arc welding robot interface, which not only realizes digital processing of various state parameter adjustments, but also realizes digital diagnosis, processing and real-time display of faults.

3. The multi-functional welding system of the underwater welding robot of the present invention adopts a convergent miniature drainage cover, which can be directly installed on the end of the welding torch, has good adaptability to the underwater welding site environment, and can realize high-quality underwater partial drying. Method welding.

4. The underwater welding robot multifunctional welding system of the present invention is designed with a digital arc welding inverter power supply dedicated to underwater, and has a unique power-underwater arc system digital adjustment capability, which can establish a stable underwater welding arc and obtain high-quality welding quality.

5. The multifunctional welding system of the underwater welding robot of the present invention adopts a full-digital submersible wire feeder with closed-loop feedback, which can not only realize stable constant-speed wire feeding and variable-speed wire feeding, but also realize Pulse wire feed.

Description of drawings

Fig. 1 is the structural block diagram of the multifunctional welding system of the underwater welding robot of the present invention;

Fig. 2 is a structural block diagram of the digitized arc welding inverter power supply of the underwater welding robot multifunctional welding system of the present invention;

Fig. 3 is the principle diagram of the main circuit of the digitized arc welding inverter power supply of the underwater welding robot multifunctional welding system of the present invention;

Figure 4(a) is a schematic diagram of the interface information flow of the arc welding robot of the underwater welding robot multifunctional welding system of the present invention;

Fig. 4(b) is a schematic diagram of the interface principle of the arc welding robot of the underwater welding robot multifunctional welding system of the present invention;

Fig. 4(c) is a structural block diagram of the information interaction module in the arc welding robot interface of the underwater welding robot multifunctional welding system of the present invention;

Fig. 5 is the schematic diagram of the ARM microcontroller of the arc welding robot interface of the underwater welding robot multifunctional welding system of the present invention;

Fig. 6 is a block diagram of the submersible wire feeder system of the underwater welding robot multifunctional welding system of the present invention;

Fig. 7 is a structural diagram of a miniature drainage cover of the underwater welding robot multifunctional welding system of the present invention.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

Example

As shown in Figure 1, the underwater welding robot multifunctional welding system of the present invention includes an arc welding robot interface 100, a digital arc welding inverter power supply 200, a submersible wire feeder 300, a robot-specific welding torch 400, a miniature drainage cover 500, a compression The gas device 600 and the shielding gas device 700; among them, the arc welding robot interface 100, the digital arc welding inverter power supply 200, the submersible wire feeder 300 and the robot-specific welding torch 400 are connected in sequence. One end of the arc welding robot interface 100 connected to the robot through the CAN bus is connected to the submersible wire feeder 300, and is respectively connected to the compressed gas device 600 and the shielding gas device 700; The cover 500 is connected, one end of which is connected with the arc load one; the compressed gas device 600 is connected with the miniature drainage cover 500 , and the protective gas device 700 is connected with the submersible wire feeder 300 .

As shown in Figure 2, the digitized arc welding inverter power supply of the underwater welding robot multifunctional welding system of the present invention includes a main circuit one 2100 and a control circuit one 2200 interconnected with the main circuit one 2100; wherein, the main circuit one 2100 is composed of a rectifier The filter circuit 2101, the inverter bridge 2102, the intermediate frequency transformer 2103 and the fast rectification and filter circuit 2106 are sequentially connected to form; the rectification and filter circuit 2101 is electrically connected to the three-phase AC input power supply, and the fast rectification and filter circuit 2104 is connected to the arc load two 2106. The first control circuit 2200 includes a power supply module 2201 electrically connected to the three-phase AC input power supply and used to provide electric energy to the first control circuit, a minimum system 2205, and an action detection module 2202 connected to the minimum system 2205, an overheat detection module 2203, an overvoltage and undervoltage Voltage detection module 2204, high-frequency drive module 2206, peak current detection module 2207, current feedback circuit 2208, digital panel 2210, CAN interface circuit 2211 and relay module 2212; among them, the minimum system 2205 is a Cortex- The M4 series chip STM32F405RGT6 is the core, which is composed of a microprocessor of the model STM32F405RGT6, a power supply circuit, a reset circuit, a crystal oscillator circuit, a JTAG interface, a miniUSB chip and peripheral circuit connections.

Two thresholds, high and low, are set in the minimum system 2205. When the feedback value exceeds the low threshold but does not reach the high threshold, the minimum system 2205 will reduce the duty of the PWM drive signal within half an inverter cycle ratio, reduce the output current to a safe value, and realize the pulse-by-pulse current limiting protection of the power tube of the inverter bridge 2102; if the current continues to increase at this time, once the feedback value exceeds the high threshold value, the minimum system 2205 will directly turn off the PWM output , to ensure the safety of the inverter bridge 2102 power tube. One end of the high-frequency drive module 2206 is connected to the PWM port of the minimum system 2205 , and the other end is connected to the inverter bridge 2102 of the main circuit one 2100 . When the power supply works in hard switching mode, the PWM port of the minimum system 2205 directly generates two channels of push-pull digital PWM signals, and when the power supply works in soft switching mode, the PWM port directly generates four channels of phase-shifted PWM signals. One end of the peak current detection module 2207 is connected to the ADC port of the minimum system 2205, and the other end is connected to the intermediate frequency transformer 2103 of the main circuit one 2100 to detect the primary side current of the intermediate frequency transformer 2103 in real time, and input the minimum system 2205 after fast and precise rectification and compensation ADC port for analog-to-digital conversion. One end of the overvoltage and undervoltage detection module 2204 is directly connected to the GPIO port of the minimum system 2205, and the other end is electrically connected to the three-phase AC input power supply. When the voltage of the three-phase AC input is low or too high, the overvoltage and undervoltage detection module 2204 The output level of will change, and the minimum system 2205 judges the undervoltage fault accordingly. The action detection module 2202 , the overheat detection module 2203 and the relay module 2212 are all connected to the GPIO port of the minimum system 2205 . The digital panel 2210 is directly connected to the UART port of the minimum system 2205. In order to simplify the design, the digital panel 2210 and the information interaction module 1006 of the arc welding robot interface 100 adopt the same structure, as shown in Figure 4(c), but the running software is different . The CAN interface circuit 2211 is directly connected to the CAN port of the minimum system 2205 . One end of the current feedback circuit 2208 is connected to the fast rectification filter circuit 2104 of the main circuit one 2100 to sample the output current and voltage value of the main circuit 2100; the other end is directly connected to the ADC port of the minimum system 2205, and the minimum system 2205 passes the sampling value through the After digital conversion, it is compared with the given value of current and voltage sent by the digital panel 2210 or the arc welding robot interface 100 from the CAN interface circuit 2211, and the deviation is calculated and processed according to a certain digital regulation rule, and the PWM port is controlled to output the corresponding duty ratio. Digital PWM signal, so as to realize precise closed-loop control on the output of main circuit one 2100.

The inverter bridge 2102 of the first main circuit 2100 adopts a hard-switching commutation mode, or a full-bridge high-frequency inverter topology working in a soft-switching mode. As shown in Figure 3, the main circuit one of the digital inverter arc welding power supply of the present invention adopts a full-bridge high-frequency inverter topology, and the three-phase AC input power supply is connected to the rectifier bridge D1-D6 of the rectifier filter circuit 2101, and then enters the filter link L1 , C1-C2, R1-R2 and D7-D8, become a relatively smooth direct current; then flow into the inverter bridge 2102, pass through the inverter bridge composed of S1-S44 power switch tubes, and pass through the high-frequency opening of the power switch tubes And turn off, convert the direct current into a high-frequency square wave alternating current; among them, D9-D12 are the anti-parallel diodes of S1-S4 respectively, and R3C3, R4C4, R5C5, R6C6 are the absorption circuits of the power transistors S1-S4 respectively. When the hard switching commutation mode is adopted, the resistance of the absorption circuit is not zero; when working in the soft switching mode, R3-R6 is zero resistance; then, the square wave current flows into the intermediate frequency transformer 2103 for step-down; after step-down The low-voltage high-frequency AC square wave enters the fast rectification filter circuit 2104 composed of D15-D16 and L2, etc., and becomes smooth low-voltage direct current.

As shown in Figure 4(b), the arc welding robot interface of the present invention includes a power supply module 1005, an ARM controller 1001, and a power supply module 1005 that is electrically connected to the three-phase AC power supply and provides the required electric energy for the entire arc welding robot interface, and is connected to the ARM control unit respectively. The feedback module 1002 connected to the controller 1001, the relay module 1003, the communication expansion module 1004, the information interaction module 1006 and the analog output module 1007 provided with a digital controller. Among them, the ARM controller 1001 uses ST's Cortex-M4 series chip STM32F405RGT6 with a main frequency of up to 168MHz as the core. Connection composition, the specific composition is shown in Figure 5. The feedback module 1002 is respectively connected with the compressed gas device and the shielding gas device, samples information such as the gas flow and pressure of the compressed air, the flow and pressure of the shielding gas, and inputs the information to the ADC port of the ARM controller 1001 after signal conditioning. The relay module 1003 is directly connected to the programmable GPIO port of the ARM controller 1001, and has multiple relay node outputs, whose outputs are respectively connected to the compressed gas device and the protective gas device, and can control the start/stop of the compressed gas device and the protective gas device . The communication extension module 1004 is directly connected to the CAN port of the ARM controller 1001, and is mainly composed of the independent controller SJA1000 supporting the CAN2.0B protocol and its peripheral circuits. interface circuit connection. The information interaction module 1006 is directly connected to the UART port of the ARM controller 1001 to realize functions such as parameter adjustment, status information display, and fault alarm. The analog output module 1007 adopts the HCNR201 linear optocoupler isolation module to isolate and amplify the 0-3.3v analog voltage generated by the STM32F405RGT6 two-way 12-bit DAC.

As shown in Figure 4(c), the information interaction module of the arc welding robot interface of the present invention adopts a visualization system solution. The main control chip adopts the M4 core ARM microprocessor STM32F407ZGT6 which integrates ARM+DSP dual-core functions. It expands and configures 16M video memory through the FSMC port, expands the 64Mbit flash memory through the SPI port, and expands the USB storage through the USB OTG port. The device is directly connected to the TIMER port, the button is directly connected to the GPIO port, and the LED status indicator is directly connected to the GPIO port. With RTOS as the real-time kernel, it has the advantages of fast data processing speed, precise and flexible adjustment, and convenient system expansion. A UART serial port is reserved to communicate with the UART of the ARM controller 1001. The parameter display adopts four-wire resistive 7-inch TFT-LCD-AT070TN92, the LCD driver chip RA8875 is directly connected with the backlight chip CAT4139, and the buttons and rotary encoder are used to display and set the parameters.

As shown in Fig. 4(a), the arc welding robot interface 100 of the present invention mainly completes the processing and transmission of various instructions, states, process parameters and fault information. The interface information flow between the arc welding robot interface 100 and the robot, digital arc welding inverter power supply 200, submersible wire feeder 300, compressed gas device 600 and shielding gas device 700 is as follows:

The instructions received by the arc welding robot interface 100 from the robot include: start/stop, current regulation, voltage regulation, and arc ignition; the information sent by the arc welding robot interface 100 to the robot includes: start/stop response, actual current value, actual voltage value, arc ignition success, actual wire feeding speed, compressed gas flow and pressure, protective gas flow and pressure, fault information (overvoltage, undervoltage, overheating, sticking wire, arc extinguishing, no welding wire, unstable arc, contact tip contact touch); these information are completed through CAN bus communication.

The signals received by the arc welding robot interface 100 from the digital arc welding inverter power supply 200 include: undervoltage, overvoltage, overheating, successful arc ignition, wire sticking, arc extinguishing, arc instability, contact tip contact, actual current value, actual Voltage value; the signals sent by the arc welding robot interface 100 to the digital arc welding inverter power supply 200 include: start/stop, arc ignition, current regulation, and voltage regulation; these information are all completed through CAN bus communication.

The signals received by the arc welding robot interface 100 from the submersible wire feeder 300 include: actual wire feeding speed, no welding wire; the signals sent by the arc welding robot interface to the submersible wire feeder include: start/stop, wire feeding speed;

The signals sent by the arc welding robot interface 100 to the compressed gas device 600 include: start/stop, flow rate, and air pressure; the signals received by the arc welding robot interface 100 from the compressed gas device 600 include: flow rate and air pressure;

The signals sent by the arc welding robot interface 100 to the shielding gas device 700 include: start/stop, flow rate, and air pressure; the signals received by the arc welding robot interface 100 from the shielding gas device 700 include: flow rate and air pressure.

Therefore, all information interactions between the arc welding robot interface 100 and the robot, the digital arc welding inverter power supply 200 and the submersible wire feeder 300 (including state information such as start/stop, process parameters, fault information, and whether the arc is successful or not) ) are all realized through digital communication based on CAN bus; and the start/stop signal between the compressed gas device 600 and the protective gas device 700 is realized through the control of the relay module, and the flow rate and air pressure are sampled through the feedback module ARM controller for arc welding robot interface 100 .

The submersible wire feeder of the present invention is provided with a sealing cover, and is composed of a wire feeding driving circuit, a wire feeding motor, a pinch wheel and a welding wire reel; In the sealed cover; one end of the special welding torch for the robot is fixed on the sealed cover of the submersible wire feeder; the protective gas device is connected with the sealed cover of the submersible wire feeder. As shown in FIG. 6 , the wire feeding drive circuit includes a main circuit two and a control circuit two connected to the main circuit two; wherein, the control circuit two is composed of an MCU controller and a peripheral circuit. The main circuit two includes a rectification and filtering circuit, a BUCK voltage stabilizing circuit, a phase commutation circuit and a chopper circuit connected in sequence; one end of the chopper circuit is connected to the wire-feeding motor, and the wire-feeding motor is connected to the ADC port of the MCU controller. The voltage is fed back to the control circuit 2; the PWM port of the MCU controller is connected to the chopper circuit of the main circuit 2 through the IR2110 driver 1 to realize the speed regulation of the motor; the TIMER port of the MCU controller is connected to the main circuit 2 through the IR2110 driver 2 The commutation circuit is connected to realize the forward and reverse control of the motor. The CAN port of the MCU controller is respectively connected with the communication expansion module of the arc welding robot interface and the CAN interface circuit of the digital arc welding inverter power supply through the CAN bus. The wire feeding motor of the present invention adopts a brushless DC motor. The second control circuit adopts STM32F405RGT6 as the main control chip, receives the wire feeding speed setting value sent by the arc welding robot interface through the CAN bus, and samples the actual working voltage of the motor end in real time, and controls the PWM port to output two complementary belt dead The time-delayed PWM signal is amplified by the IR2110 driver to drive the chopper circuit to adjust the speed and steering of the motor; the low-frequency PWM signal is output through the TIMER port of the MCU controller, and then amplified by the IR2110 driver to drive the commutation circuit , to realize the positive and negative rotation control of the motor, through the commutation control and chopping control, three wire feeding modes can be realized, such as constant speed wire feeding, variable speed wire feeding and pulse wire feeding.

As shown in Figure 5, in order to simplify the design and improve the system development efficiency, the ARM microcontroller in the arc welding robot interface of the present invention and the digital controller of the information interaction module, the minimum system in the digital arc welding inverter power supply control circuit and The MCU controller of the digital panel and the submersible wire feeder adopts the minimum system of Cortex-M4 core STM32F405RGT6 of ST Company with a main frequency up to 168MHz. Power supply circuit composed of S1, C1, R7, etc., crystal oscillator circuit composed of Y1, C2-3, R1, JTAG interface composed of R5-8, JTAG chip, miniUSB chip and peripheral circuit connection . STM32F405RGT6 built-in DSP function module is a SOC-level chip based on Cortex-M4 core, with up to 1MB on-chip FLASH, 192Kb SRAM, 12-bit ADC with a conversion rate of 2.4MSPS, and two 12-bit DACs that can generate 0-3.3v The analog voltage, UART, RS485 and CAN interfaces are reserved. STM32F405RGT6 is the digital core of arc welding robot interface, digital inverter arc welding power supply and submersible wire feeder. Its interior is respectively solidified with arc welding robot interface software based on FreeRTOS real-time kernel, digital arc welding inverter power supply control software and submersible wire feeder machine control software.

As shown in Figure 7, the miniature drainage cover of the present invention adopts a convergent shrinkage nozzle structure. There are 4 inlet pipes with a diameter of 8mm on the upper part of the nozzle. The compressed air generated by the compressed gas device is input through these 4 inlet pipes. The diameter of the bottom of the shrinkage pipe is 24mm, which can ensure the cross-sectional area of the compressed gas input gas passage. The cross-sectional area is larger than the bottom of the shrink tube, so as to ensure that the air flow below the speed of sound is continuously accelerated in the pipe with a gradually reduced cross-sectional area, forming a high-stiffness high-pressure air curtain around the welding point, and draining the water in the welding area, so that It can make the welding arc burn in the gas phase area, realize reliable partial dry welding, and improve the quality of the weld seam. The material of the miniature drainage cover is 304 stainless steel, and the size parameters are as shown in the figure. Among them, the curve of the inner wall surface of the shrinking nozzle can be calculated by the Vickers formula; the entire drainage cover is very small in size, which is suitable for welding all-position welds underwater.

The above-mentioned embodiment of the underwater welding robot multifunctional welding system of the present invention has the following characteristics:

1. Full digitalization: This embodiment is the first to build a full digital control platform for an underwater welding robot multifunctional welding system based on a SOC-level Cortex-M4 core, an ARM microprocessor that integrates ARM+DSP dual-core functions, and a FreeRTOS real-time kernel. , realize the full digitalization of arc welding robot interface, arc welding inverter power supply, submersible wire feeder, etc., with precise control, convenient operation and flexible expansion;

2. High flexibility: This embodiment makes full use of the advantages of the all-digital control system, and can realize digital transmission, visual operation and real-time monitoring of various fault diagnosis, status display, parameter setting, etc.;

3. Wide adaptability: the arc welding inverter power supply of the present invention can realize various characteristic outputs through digital control, and the adjustment is fast and accurate. The drainage cover is small in size, can effectively drain the water in the welding area, and can establish a micro-gas phase zone in the underwater all-position welding area. The combination of these three can establish a stable power supply-underwater arc system to achieve high-quality underwater welding;

4. High efficiency: This embodiment adopts the full-bridge high-frequency inverter technology, which has strong power transmission, high energy conversion efficiency, low voltage borne by the power tube, short main circuit time, good dynamic performance, high efficiency, energy saving, and material saving .

The above-mentioned embodiment is a preferred embodiment of the present invention, but the embodiment of the present invention is not limited by the above-mentioned embodiment, and any other changes, modifications, substitutions, combinations, Simplifications should be equivalent replacement methods, and all are included in the protection scope of the present invention.

Claims (10)

1.Yi Zhong Underwater Welding robot Multifunctional welding welding system, is characterized in that: comprise arc welding robot interface, Research of Digital Arc Welding Inverter, diving wire-feed motor, the special-purpose welding torch of robot, Mini drain cap, Ignitable gas devices and protective gas device; The special-purpose welding torch of described arc welding robot interface, Research of Digital Arc Welding Inverter, diving wire-feed motor and robot is connected successively; Described arc welding robot interface is also connected with protective gas device with robot, diving wire-feed motor, Ignitable gas devices respectively; The special-purpose welding torch of described robot is installed in robot, and is also connected with Mini drain cap, arc load one; Described Ignitable gas devices is connected with Mini drain cap, and protective gas device is connected with diving wire-feed motor.

2. Underwater Welding according to claim 1 robot Multifunctional welding welding system, is characterized in that: described Research of Digital Arc Welding Inverter comprise main circuit one and with the interconnective control circuit one of main circuit one; Described main circuit one is connected to form successively by current rectifying and wave filtering circuit, inverter bridge, intermediate-frequency transformer and quick current rectifying and wave filtering circuit; Described current rectifying and wave filtering circuit is electrically connected to three-phase alternating current input power, and current rectifying and wave filtering circuit is connected with arc load two fast.

3. Underwater Welding according to claim 2 robot Multifunctional welding welding system, is characterized in that: the inverter bridge of described main circuit one adopts and works in hard switching commutating mode, or adopts the full-bridge high-frequency inversion topological structure that works in soft switching mode.

4. Underwater Welding according to claim 2 robot Multifunctional welding welding system, is characterized in that: described control circuit one comprises and being electrically connected to three-phase alternating current input power and for supply module, minimum system and the motion detection module being connected with minimum system respectively, overheated detection module, over-and under-voltage detection module, high-frequency drive module, peak current detection module, current feedback circuit, digitizing tablet, CAN interface circuit and the relay module of electric energy are provided to control circuit one; Wherein, described over-and under-voltage detection module is electrically connected to three-phase alternating current input power.

5. Underwater Welding according to claim 4 robot Multifunctional welding welding system, it is characterized in that: described high-frequency drive module is connected with the inverter bridge of main circuit one, peak current detection module is connected with the intermediate-frequency transformer of main circuit one, and current feedback circuit is connected with the quick current rectifying and wave filtering circuit of main circuit one; The minimum system of described control circuit one is provided with Pulse by Pulse current-limiting protection and direct two kinds of protected modes of turn-off protection.

6. Underwater Welding according to claim 4 robot Multifunctional welding welding system, is characterized in that: described arc welding robot interface comprises supply module, ARM controller and the feedback module being connected with ARM controller respectively, relay module, communication expansion module for electric energy is provided, is provided with information interaction module and the analog output module of digitial controller; Wherein, described communication expansion module is connected with the CAN interface circuit of control circuit one by CAN bus; Described arc welding robot interface is connected and refers to protective gas device with Ignitable gas devices respectively: described relay module is connected with protective gas device with Ignitable gas devices respectively, for controlling the startup of Ignitable gas devices and protective gas device and closing down; Described feedback module is connected with protective gas device with Ignitable gas devices respectively, for gathering the information of Ignitable gas devices and protective gas device.

7. Underwater Welding according to claim 6 robot Multifunctional welding welding system, is characterized in that: described diving wire-feed motor is provided with seal closure, and is connected to form by wire feed drive circuit, wire feeding motor, contact roller and wire reel; Described wire feed drive circuit, wire feeding motor, contact roller and wire reel are installed in seal closure; One end of the special-purpose welding torch of described robot is fixed on the seal closure of diving wire-feed motor; Described protective gas device is connected with the seal closure of diving wire-feed motor.

8. Underwater Welding according to claim 7 robot Multifunctional welding welding system, is characterized in that: described wire feed drive circuit comprises main circuit two and the control circuit two being connected with main circuit two; Described control circuit two is connected and composed by MCU controller and peripheral circuit; Described main circuit two comprises current rectifying and wave filtering circuit, BUCK mu balanced circuit, commutation circuit and the chopper circuit connecting successively; Described chopper circuit one end is connected with wire feeding motor, and wire feeding motor is connected by the ADC port with MCU controller, and Voltage Feedback is arrived to control circuit two; The PWM port of described MCU controller is connected with the chopper circuit of main circuit two by IR2110 driver one, to realize the speed governing to motor; The TIMER port of described MCU controller is connected with the commutation circuit of main circuit two by IR2110 driver two, to realize motor positive and inverse, controls; The CAN port of described MCU controller is connected with the communication expansion module of arc welding robot interface and the CAN interface circuit of Research of Digital Arc Welding Inverter respectively by CAN bus.

9. Underwater Welding according to claim 8 robot Multifunctional welding welding system, is characterized in that: microprocessor, power circuit, reset circuit, crystal oscillating circuit, jtag interface, miniUSB chip and peripheral circuit that the MCU controller of the minimum system in the ARM microcontroller in described arc welding robot interface and the digitial controller of information interaction module, Research of Digital Arc Welding Inverter control circuit and digitizing tablet and diving wire-feed motor is STM32F405RGT6 by model connect and compose.

10. Underwater Welding according to claim 1 robot Multifunctional welding welding system, is characterized in that: described Mini drain cap is convergent contour shrink nozzle structure.

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