CN107942769B - Communication system and method for digital power supply and various digital welding devices - Google Patents

Detailed Description

It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Referring to fig. 1, fig. 1 is a block diagram of a communication system of a digital power supply and a plurality of digital welding devices according to a first embodiment of the present invention.

In this embodiment, the communication system between the digital power supply and the plurality of digital welding devices includes: an RS485 bus 10, a digital power supply 20 and a plurality of digital welding devices 30;

the RS485 bus 10 is used for connecting the digital power supply 20 and each digital welding device 30;

it can be understood that the networking mode of the RS485 bus network is simple, the construction cost is low, and a unified bus communication protocol is not available up to now. At present, when an application system based on an RS485 bus network is developed, an RS485 bus communication protocol is often designed temporarily, so that certain problems exist in the aspects of portability, high efficiency and stability of the system. In this embodiment, the digital power supply 20 and each digital welding device 30 are connected through the RS485 bus 10, and a set of RS485 bus communication protocol is customized, so that the communication between the digital power supply 20 and each digital welding device 30 is high in speed and strong in anti-interference performance.

It should be understood that the various digital welding devices 20, include: the welding robot is used for welding the workpiece, and the welding robot is used for welding the workpiece.

The digital power supply 20 is configured to send an inquiry instruction with the device address of each digital welding device 30 as a frame header through a preset RS485 bus communication protocol;

it should be understood that the preset RS485 bus communication protocol is a set of complete, high-speed, robust, reliable, simple and economical communication protocols customized according to the communication requirements between the digital power supply 20 and each digital welding device 30. In order to apply the 485 bus to the field of high-current strong-interference welding automation with the working current of more than 100A, the preset RS485 bus communication protocol is divided into a data conversion layer and an application management layer, the data conversion layer plans the structure and conversion of each frame of data, and the application management layer is divided into digital power supply application management and digital welding equipment application management.

Referring to fig. 2, fig. 2 is a structural diagram of one frame data. In the data conversion layer, as shown in fig. 2, one frame of data is divided into: frame head, frame type identification, frame data, frame check sum and frame tail. The frame head (ADDRESS) is only one BYTE (BYTE), and is a synchronous code and an ADDRESS code of one frame of data, the frame head in the digital power supply is an ADDRESS sent to each digital welding device, the frame head in each digital welding device is identified as an ADDRESS of the local device, and characters of the frame head are limited to 16-system identifications 0Xf 0-0 Xfd. The end of frame (QUEUE), which has only one BYTE (BYTE), is only limited to 16-ary identification 0 Xfe. The Frame type identifier (BYTE1) has only one BYTE (BYTE), the second code of a Frame of data is the Frame type identifier, and in a Frame type identifier, only half of the Frame type identifier is called as a Frame type (Frame type) which plays a role of the Frame type identifier. The other half is data, and the lower three bits bit 0-bit 2, bit3 are spare in the digital power supply to serve as frame type identification. What serves as a frame type identifier in each digital welding apparatus is the lower 4 bits bit 0-bit 3. The frame data (BYTE 2-BYTE 5) has 4 BYTEs (BYTE), and 2 nd code to 5 th code of one frame data are frame data. The frame check (CHECKSUM) only has one BYTE (BYTE), the 6 th code of one frame of data is a check code, and the check code is obtained by certain operation of a frame type identifier and 4 frames of data. Data conversion: the frame type identifier together with 4 data, 5 BYTEs are called a data packet (DATA PACKET), and one data packet together with check code, 6 BYTEs, are converted into 12 ASCII codes through certain operation. The final frame data includes 14 BYTEs (BYTE) for the frame head and the frame tail.

The frame type identification in a frame data structure and the frame data form a data packet, and a certain specific operation G is performed to generate a frame check code of the frame data. Data packets in a frame data structure and data of 6 BYTEs obtained by performing G operation on the data packets are subjected to data conversion B to generate 12 ASCII codes ASCII 0-ASCII 12. The end of frame QUEUE of the structure of one frame of data is the end code of one frame of data whose value is limited to 0 Xfe. When the receiving end receives the frame end, the receiving end indicates that the receiving of one frame of data is completed. The complete structure of the frame of data is ADDRESS, ASCII 0- -ASCII 12 and QUEUE. When each digital welding Device 30 is used as a receiving end, such frame data received from the RS485 bus is firstly compared to determine whether the ADDRESS is the same as the Device ADDRESS Device _ ID of the Device, and if the ADDRESS is not the same as the Device ADDRESS Device _ ID of the Device, the frame data is discarded, if the ADDRESS is the same as the Device ADDRESS Device _ ID of the Device, ascii 0-ascii 12 is decoded into BYTE 1-BYTE 5 and check code check sum through operation D, and BYTE 1-BYTE 5 are compared between the frame check code obtained through the G operation and the check code check sum obtained through operation D, and if the two check codes are different, the frame data is discarded. If so, BYTE 1-BYTE 5 is received. The difference between digital power supply 20 as a receiver and each digital welding device as a receiver is that digital power supply 20 distinguishes which digital welding device 30 originated from the frame header ADDRESS, and if the ADDRESS is not 0Xf 0-0 Xfd then the frame of data is an error. The G operation is characterized in that a programmer can arbitrarily define the operation G to verify data.

It will be appreciated that the digital power supply 20 sends a query command beginning with the device address of each digital welding device 30 during the transmit time slot, and by addressing, looks for all digital welding devices 30 that are connected to the system via the RS485 bus.

The digital power supply 20 is further configured to establish communication connection with each digital welding device 30 when receiving response information of each digital welding device 30 with its device address as a frame header;

it should be noted that the digital power supply 20 receives the reply with the same device address as the inquiry command as the frame head in the receiving time slot, and if the digital welding device corresponding to the device address does not exist, the reply is not obtained in the receiving time slot. If the digital power source 20 does not receive the correct response of the digital welding devices 30 during each receive time slot, a communication connection cannot be established with each digital welding device 30. When the digital power supply 20 receives a correct reply sent by a digital welding device 30, the digital power supply 20 establishes a communication connection with the digital welding device 30 that sent the correct reply.

It should be understood that the frame header ADDRESS of the structure of a frame of data, which is both an ADDRESS of a device and a synchronization code, is represented by a 16-ary frame header code, and its value is limited to 0Xf 0-0 Xfd, the digital power source 20 takes the device ADDRESS as the frame header, the frame header is transmitted as the header code, each digital welding device 30 starts receiving at the frame header synchronization, and compares the frame header transmitted by the digital power source 20 with the device ADDRESS of each digital welding device 30, and when the frame header transmitted by the digital power source 20 matches the device ADDRESS of one digital welding device 30, the digital welding device 30 with the same device ADDRESS filters out the data transmitted by the digital power source 20 and identifies that the digital welding device 30 has established a communication connection with the digital power source 20.

The digital welding device 30 is configured to receive the query instruction sent by the digital power supply 20 through a preset RS485 bus communication protocol, and send response information including a device address of each digital welding device 30 as a frame.

It is to be appreciated that, after the digital power supply 20 sends a query command beginning with the device address of each digital welding device, the digital welding device 30, the inquiry command sent by the digital power supply 20 is received through a preset RS485 bus communication protocol, when the device address sent by the digital power source 20 matches the device address of one of the digital welding devices 30, the digital welding device 30 with the same device address filters out the data sent by the digital power supply 20, and after the digital welding device 30 successfully receives the data, the digital welding device sends response information with the device address as the frame head to the digital power supply 20, the digital power supply 20 receives the reply message, compares its device address with the device address in the transmitted query command, when consistent, it is deemed that a proper response has been received, identifying the digital welding device 30 as establishing a communication connection with the digital power supply 20 via the RS485 bus.

In the embodiment, a set of preset RS485 bus communication protocol is designed to establish communication connection between the digital power supply and each welding device, so that the digital power supply and each welding device are strong in communication anti-interference performance, high in reliability, simple, convenient and economical.

Referring to fig. 3, a second embodiment of a communication system for a digital power source and a plurality of digital welding devices of the present invention is provided based on the first embodiment.

In this embodiment, the digital power supply 20 'is further configured to send a first preset type query instruction to each digital welding device 30' in turn during power-on initialization;

it can be understood that the preset RS485 bus communication protocol is divided into a data conversion layer and an application management layer, and the application management layer is divided into digital power supply application management and digital welding equipment application management. The welding power source protocol is as follows: in the standby state, all digital welding devices 30' that access the system via the 485 bus are sought by addressing. For the digital power supply 20', the signal on the RS485 bus is divided into a transmission slot and a reception slot. The sending time slot sends a query command with the device address of each digital welding device 30 'as the frame head, the receiving time slot receives response information with the same device address as the frame head, and if the digital welding device 30' corresponding to the device address does not exist, the response information cannot be obtained in the receiving time slot. The queries issued by the digital power supply 20' are of 4 different types, identified by frame type identifiers. Referring to the one-frame data structure diagram of fig. 2, the data structure for each type of query instruction is detailed as follows:

frame 0: the frame signal is transmitted during the welding process, and the structure is as follows,

the frame header is the device address; the lower three bits bit 0-bit 2 of BYTE1 identify Frame0, bit3 of BYTE1 for standby, bit4 and bit5 of BYTE1 transmit the lower two bits of welding voltage, and bit6 and bit7 of BYTE1 transmit the lower two bits of welding current; BYTE2 carries the remaining upper 8 bits of welding current; BYTE3 carries the remaining upper 8 bits of the welding voltage; BYTE4 conveys the wire feed speed of the wire feeder during welding; BYTE5 conveys various states during welding; followed by a frame checksum and an end of frame.

Frame 1: the frame signal is sent in the gas detection process, and the structure is as follows,

the frame header is the device address; the lower three bits bit 0-bit 2 of BYTE1 identify Frame1, bit3 of BYTE1 for standby, bit4 and bit5 of BYTE1 transmit the lower two bits of welding voltage, and bit6 and bit7 of BYTE1 transmit the lower two bits of welding current; BYTE2 carries the remaining upper 8 bits of welding current; BYTE3 carries the remaining upper 8 bits of the welding voltage; BYTE4 conveys the wire feed speed of the wire feeder during welding; BYTE5 conveys gas flow during gas detection; followed by a frame checksum and an end of frame.

Frame1 differs from Frame0 in the Frame type identifier and BYTE5, BYTE5 carries the gas flow during the gas detection process.

Frame 2: the frame signal is transmitted in a standby state, and has a structure as follows,

the frame header is the device address; the lower three bits bit 0-bit 2 of BYTE1 identify Frame2, bit3 of BYTE1 for standby, bit4 and bit5 of BYTE1 transmit the lower two bits of welding voltage, and bit6 and bit7 of BYTE1 transmit the lower two bits of welding current; BYTE2 carries the remaining upper 8 bits of welding current; BYTE3 carries the remaining upper 8 bits of the welding voltage; BYTE4 conveys the wire feed speed of the wire feeder during welding; BYTE5 conveys gas pressure during gas detection; followed by a frame checksum and an end of frame.

Frame2 differs from Frame0 in that the Frame type identifier and BYTE5, BYTE5 convey the pressure of the gas during the gas detection process.

Frame 3: the frame signal is transmitted in a standby state, and has a structure as follows,

the frame header is the device address; the lower three bits bit 0-bit 2 of BYTE1 identify Frame3, bit3 of BYTE1 for standby, bit4 and bit5 of BYTE1 transmit the lower two bits of welding voltage, and bit6 and bit7 of BYTE1 transmit the lower two bits of welding current; BYTE2 carries the remaining upper 8 bits of welding current; BYTE3 carries the remaining upper 8 bits of the welding voltage; BYTE4 conveys the wire feed speed of the wire feeder during welding; BYTE5 conveys the real-time alert code of the system; followed by a frame checksum and an end of frame.

Frame3 differs from Frame0 in that the Frame type identifier and BYTE5, BYTE5 convey the real-time alarm code of the system.

It should be noted that, as shown in fig. 4, fig. 4 is a signal flow chart of the digital power source 20 'sending signals to each digital welding device 30', and the first preset type query command is: frame0, Frame1, Frame2, and Frame 3. Upon power-up initialization of the system, the digital power supply 20 'takes turns sending query commands for Frame0, Frame1, Frame2, and Frame3 to each digital welding device 30'.

The digital power supply 20 'is further configured to receive first type response information sent by each digital welding device 30', and enter a standby state when the number of times of receiving the first type response information exceeds a preset number of times;

it should be understood that there are 7 different types of reply messages sent by the digital welding apparatus 30', identified by frame type identifiers. Referring to the structure diagram of one frame data of fig. 2, the data structure of each type of response message is detailed as follows:

frame 0: this frame signal transmits software and hardware version information of the digital welding apparatus 30', which is structured as follows,

the frame head is the equipment address of the digital welding equipment; the low 4 bits bit 0-bit 3 of BYTE1 identify Frame0, bits 4-bit 7 of BYTE1 stand-by, BYTE2 transfers the hardware version of the digital welding device, BYTE2 transfers the software version of the digital welding device, BYTE4 stands-by, BYTE5 stands-by, followed by Frame checksum and Frame trailer.

Frame 1: this frame signal is responsive to an interrogation of the digital power supply 20' when the digital power supply 20' and each digital welding device 30' enter a welding state, and is structured as follows,

the frame header is the device address of the digital welding device 30'; the low 4 bits bit 0-bit 3 of BYTE1 identify Frame1, bits 4-bit 6 of BYTE1 are standby, and bits 7 of BYTE1 are starting signals and are used as a starting switch of a digital power supply 20', namely, the digital power supply is equivalent to a gun switch (torch push button) of a welding machine; BYTE2 transmits the MAIN high 8-bit MAIN SETH of the digital power supply; BYTE3 carries the MAIN low 8-bit MAIN SETL of the digital power supply; BYTE4 transmits the secondary high 8-bit SECOND SETH of the digital power supply; BYTE5 delivers a secondary low 8-bit SECOND SETL of the digital power supply; followed by a frame checksum and an end of frame.

By MAIN SET is meant: MAIN SET is the welding current setting when the welding mode is unitary (sine) or pulse (pulse) or double pulse (double pulse); MAIN SET is the welding voltage setting when the welding mode is Standard (Standard) mode; by SECOND SET is meant: SECOND SET is the welding arc length setting when the welding mode is unitary (sine) or pulse (pulse) or double pulse (double pulse); SECOND SET is the welding wire feed speed setting when the welding mode is Standard (Standard) mode; when MAIN SET is 0, SECOND SETL is disabled, and the parameters of the digital power supply 20' are given to Frame3 for setting.

Frame 2: this frame of signals, which is responsive to the interrogation of the digital power supply 20' when the digital power supply 20' and each digital welding device 30' enter a sensing state, is configured as follows,

the frame header is the device address of the digital welding device 30'; the low 4 bits bit 0-bit 3 of BYTE1 identify Frame2, bit 4-bit 7 of BYTE1 for standby; bit7 and bit6 of BYTE2 are reserved; bit5 gas detection switch (gas test); bit4 air blow switch (aria test); bit3 wire feed (motor forward continuous); bit2 drawstring (motor back coiled continuous yarn); bit1 fixed length wire feed (motor step forward); bit0 fixed length drawing (motor step backward); BYTE3 is given for wire feed speed when BYTE2 bit3 or bit2 or bit1 or bit0 is 1; BYTE4 gives the upper 8 bits for a given wire feed length when bit1 or bit0 of BYTE2 is 1; BYTE5 gives the lower 8 bits for the wire feed length when bit1 or bit0 of BYTE2 is 1; followed by a frame checksum and an end of frame.

Frame 3: this frame signal is a signal that the system answers to the inquiry of the digital power supply 20' in the standby state, and is structured as follows,

the frame header is the device address of the digital welding device 30'; the low 4 bits bit 0-bit 3 of BYTE1 identify Frame3, bit 4-bit 7 of BYTE1 for standby; BYTE2 welding program number (program of welding); BYTE3 weld JOB number (JOB number); BYTE4 for later use; BYTE5 for later use; followed by a frame checksum and an end of frame.

When the BYTE3 welding JOB number (JOB number) of the Frame3 is set to 0, the subsequent frames 4, 5, 6 and 7 must set and send reply information to the digital power supply 20', otherwise the frames 4, 5, 6 and 7 are invalid.

Frame4, Frame5, Frame6, and Frame 7: these 4 frames are the signals which answer the inquiry of the digital power supply 20' when the system is in the standby state and the job number is set to 0, and the configuration is as follows,

frame 4: the low 4 bits bit 0-bit 3 of BYTE1 identify Frame4, bit 4-bit 7 of BYTE1 for standby; BYTE2 welding mode: 1 manual gas shield welding (mig manual), 2 unified gas shield welding (mig synergy), 3 single pulse welding (mig pulse), 4 double pulse welding (mig double), 11 welding rod welding (stick), 12 argon arc welding (tig) and 13 carbon arc gas gouging (arc); BYTE3slope up (current ramp up); BYTE4I start (starting current); BYTE5t start (arc start time); followed by a frame checksum and an end of frame.

Frame 5: the low 4 bits bit 0-bit 3 of BYTE1 identify Frame5, bit 4-bit 7 of BYTE1 for standby; BYTE2 slopdo (current ramp down); BYTE3I stop (arc strike current); BYTE4t stop (arc time); BYTE5start lift; followed by a frame checksum and an end of frame.

Frame 6: the low 4 bits bit 0-bit 3 of BYTE1 identify Frame6, bit 4-bit 7 of BYTE1 for standby; BYTE2hot start (hot start); BYTE3 inductance; BYTE4bbt (burn-back time); BYTE5pregas (forward blow);

followed by a frame checksum and an end of frame.

Frame 7: the low 4 bits bit 0-bit 3 of BYTE1 identify Frame7, bit 4-bit 7 of BYTE1 for standby; BYTE2double frequency (double pulse frequency); BYTE3balance (double pulse peak base duty cycle); BYTE4I low (base current); BYTE5 for later use; followed by a frame checksum and an end of frame.

It should be noted that, when the welding system is initialized, the digital power source 20' sends the first type query commands of Frame0, Frame1, Frame2, and Frame3 to each digital welding device 30' in turn, and each digital welding device 30' responds to Frame0, that is, the first type response message is Frame 0. The preset number is a self-defined polling number, which may be 10 times, or may be set to another value, which is not limited in this embodiment. The digital power supply 20 'sends the first type of query command to each digital welding device 30' 10 times in turn, and when the digital power supply 20 'receives 10 correct responses of the Frame0 of each digital welding device 30' during the receiving time slot and the device status of the digital power supply 20 'and each digital welding device 30' is normal, the digital power supply 20 'and each digital welding device 30' enter a standby state, otherwise, an alarm state is entered.

The digital welding device 30' is further configured to receive a first preset type query command sent by the digital power supply 20' and send a first type response message to the digital power supply 20' during power-on initialization.

It will be appreciated that, at power-on initialization, the digital welding device 30 'upon receiving a first preset type of query command sent by the digital power supply 20' in turn: frame0, Frame1, Frame2, and Frame3, first type response information is transmitted to the digital power supply 20': frame 0.

In this embodiment, the digital power supply 20 'is further configured to send a first preset type query instruction to each digital welding device 30' in turn in the standby state;

it should be appreciated that in the standby state, the digital power supply 20 'in turn sends a first preset type of query to each digital welding device 30': frame0, Frame1, Frame2, and Frame 3.

The digital power supply 20 'is further configured to receive second type response information sent by each digital welding device 30', and enter a welding state when the second type response information includes a welder start signal;

it is to be understood that when the JOB NUMBER of the communication system of the digital power source and the plurality of digital welding devices is equal to 0, the parameters of the communication system are given by each digital welding device 30', and the second type of response information that each digital welding device 30' responds is Frame1, Frame2, Frame3, Frame4, Frame5, Frame6, and Frame 7. When the JOB NUMBER is not equal to 0, the parameters of the communication system are given by the various JOBs set by the digital power supply 20 'and are invoked by the JOB NUMBER in the Frame 3in the response message of each digital welding device 30'. The digital power source 20 'sends Frame0, Frame1, Frame2 and Frame3 to each digital welding device 30' in turn, and at this time, the second type of response information is: frame1, Frame2, Frame 3.

It should be appreciated that when the torch switch of the Frame1 received by the digital power supply 20 'in the reply message of each digital welding device 30' during the receive time slot is 1, the digital power supply 20 'and each digital welding device 30' enter a welding state and an alarm state if an anomaly occurs.

The digital welding device 30' is configured to receive a first preset type query command sent by the digital power supply 20' and send a second type response message to the digital power supply 20' in the standby state.

It will be appreciated that in the standby state, the digital welding device 30 'receives a first preset type of query command sent by the digital power supply 20': frame0, Frame1, Frame2, and Frame3, and when JOB NUMBER is equal to 0, transmits second type response information: frame1, Frame2, Frame3, Frame4, Frame5, Frame6, and Frame7 to the digital power supply 20', when the JOB NUMBER is not equal to 0, second type response information is transmitted: frame1, Frame2, Frame3 to the digital power supply 20'.

In this embodiment, the digital power supply 20' is further configured to enter a test state when each switch signal in the received second type response information is first preset data in the standby state.

It is to be understood that the digital power source 20 'and each digital welding device 30' enter a test state when the digital power source 20 'receives, in a receive time slot, one and only one of the respective switch signals in the BYTE2 of the Frame2 in the reply message of each digital welding device 30'. The customized first preset data is that one and only one of the switch signals in the BYTE2 of the Frame2 is 1.

In this embodiment, by designing the structure and the communication rule of the communication data between the welding power supply 20 'and each digital welding device 30', when the preset rule is satisfied, the digital power supply 20 'and each digital welding device 30' exit the test state and enter the corresponding standby state or welding state, so that the effective communication between the welding power supply 20 'and each digital welding device 30' is realized, and the communication is convenient and fast and has high reliability.

Further, referring to fig. 5, a third embodiment of a communication system for a digital power source and a plurality of digital welding devices of the present invention is provided based on the second embodiment.

In the present embodiment, the digital power source 20 "is further configured to alternately send a second preset type query command to each digital welding device 30" in the welding state;

it should be understood that, in the welding state, the digital power supply 20 "sends in turn a second preset type of inquiry command to each digital welding device 30": frame 0.

The digital power supply 20 'is also used for receiving third type response information sent by each digital welding device 30', and enters a standby state when the third type response information comprises a welding machine closing signal;

it will be appreciated that the third type of response information for each digital welding device 30 "is: frame 1. When the digital power supply 20 "receives a torch switch of 0 in the response information Frame1 of each digital welding device 30" at a receiving time slot, that is, receives a welder-off signal, the digital power supply 20 "and each digital welding device 30" exit the testing state, exit the welding state, and enter the standby state. And if the abnormity occurs, entering an alarm state.

The digital welding device 30 "is further configured to receive a second preset type of query command sent by the digital power source 20" and send a third type of response message to the digital power source 20 "in the welding state.

It should be noted that, in the welding state, the digital welding device 30 ″ receives the second preset type query command sent by the digital power supply 20 ″: frame0, a third type of response message is sent to each digital welding device 30 ″: frame 1.

In this embodiment, the digital power supply 20 ″ is further configured to send a third preset type query instruction to each digital welding device 30 ″ in turn and receive a fourth type response message sent by each digital welding device 30 ″ in the test state;

it should be understood that in the test state, the digital power supply 20 "sends in turn a third preset type of query command to each digital welding device 30": frame1, fourth type of response message for each digital welding device 30 ″: frame 2.

The digital power supply 20 ″ is further configured to enter a standby state when each switching signal in the fourth type of response information is second preset data;

it should be noted that, when the digital power supply 20 ″ receives the switch signals of the BYTE2 of the Frame2 in the response message of each digital welding device 30 ″ all being 0 in the receiving time slot, the digital power supply 20 ″ and each digital welding device 30 ″ exit the testing state and enter the standby state, and if an abnormality occurs, the digital power supply 20 ″ enters the alarm state. Each switch signal in the BYTE2 with the second preset data of Frame2 as self-defined is 0.

The digital welding device 30 "is further configured to receive a third preset type of query command sent by the digital power source 20" and send a fourth type of response message to the digital power source 20 "in the test state.

It will be appreciated that in the test state, the digital welding device 30 "receives a third preset type of query command sent by the digital power supply 20": frame1, and sends a fourth type of response message to the digital power supply 20 ″: frame 2.

In this embodiment, by designing the structure of the communication data between the welding power supply 20 ″ and each digital welding device 30 ″ and the communication rule, when the preset rule is satisfied, the digital power supply 20 ″ and each digital welding device 30 ″ exit from the welding state and enter the corresponding standby state or exit from the test state and enter the standby state, so that the effective communication between the welding power supply 20 ″ and each digital welding device 30 ″ is realized, and the communication is convenient and fast and has high reliability.

Referring to fig. 6, a first embodiment of a method of communicating a digital power source with a plurality of digital welding devices based on a system for communicating the digital power source with the plurality of digital welding devices is presented.

The communication system based on the digital power supply and various digital welding machine devices comprises: RS485 bus, digital power supply and various digital welding devices; the communication method of the digital power supply and each digital welding device comprises the following steps:

s10: the RS485 bus is connected with the digital power supply and each digital welding device;

it can be understood that the networking mode of the RS485 bus network is simple, the construction cost is low, and a unified bus communication protocol is not available up to now. At present, when an application system based on an RS485 bus network is developed, an RS485 bus communication protocol is often designed temporarily, so that certain problems exist in the aspects of portability, high efficiency and stability of the system. In the embodiment, the digital power supply and each digital welding device are connected through the RS485 bus, and a set of RS485 bus communication protocol is manufactured in a user-defined mode, so that the communication between the digital power supply and each digital welding device is high in speed and strong in anti-interference performance.

It should be understood that the various digital welding devices include: the welding robot is used for welding the workpiece, and the welding robot is used for welding the workpiece.

S20: the digital power supply sends a query instruction with the device address of each digital welding device as a frame head through a preset RS485 bus communication protocol;

it should be understood that the preset RS485 bus communication protocol is a set of complete, high-speed, anti-interference, reliable, simple and economical communication protocols customized according to the communication requirements between the digital power supply and each digital welding device. In order to apply the 485 bus to the field of high-current strong-interference welding automation with the working current of more than 100A, the preset RS485 bus communication protocol is divided into a data conversion layer and an application management layer, the data conversion layer plans the structure and conversion of each frame of data, and the application management layer is divided into digital power supply application management and digital welding equipment application management.

S30: the digital welding equipment receives the inquiry instruction sent by the digital power supply through a preset RS485 bus communication protocol, and sends response information with the equipment address of each digital welding equipment as a frame head;

referring to fig. 2, fig. 2 is a structural diagram of one frame data. In the data conversion layer, as shown in fig. 2, one frame of data is divided into: frame head, frame type identification, frame data, frame check sum and frame tail. The frame head (ADDRESS) is only one BYTE (BYTE), and is a synchronous code and an ADDRESS code of one frame of data, the frame head in the digital power supply is an ADDRESS sent to each digital welding device, the frame head in each digital welding device is identified as an ADDRESS of the local device, and characters of the frame head are limited to 16-system identifications 0Xf 0-0 Xfd. The end of frame (QUEUE), which has only one BYTE (BYTE), is only limited to 16-ary identification 0 Xfe. The Frame type identifier (BYTE1) has only one BYTE (BYTE), the second code of a Frame of data is the Frame type identifier, and in a Frame type identifier, only half of the Frame type identifier is called as a Frame type (Frame type) which plays a role of the Frame type identifier. The other half is data, and the lower three bits bit 0-bit 2, bit3 are spare in the digital power supply to serve as frame type identification. What serves as a frame type identifier in each digital welding apparatus is the lower 4 bits bit 0-bit 3. The frame data (BYTE 2-BYTE 5) has 4 BYTEs (BYTE), and 2 nd code to 5 th code of one frame data are frame data. The frame check (CHECKSUM) only has one BYTE (BYTE), the 6 th code of one frame of data is a check code, and the check code is obtained by certain operation of a frame type identifier and 4 frames of data. Data conversion: the frame type identifier together with 4 data, 5 BYTEs are called a data packet (DATA PACKET), and one data packet together with check code, 6 BYTEs, are converted into 12 ASCII codes through certain operation. The final frame data includes 14 BYTEs (BYTE) for the frame head and the frame tail.

The frame type identification in a frame data structure and the frame data form a data packet, and a certain specific operation G is performed to generate a frame check code of the frame data. Data packets in a frame data structure and data of 6 BYTEs obtained by performing G operation on the data packets are subjected to data conversion B to generate 12 ASCII codes ASCII 0-ASCII 12. The end of frame QUEUE of the structure of one frame of data is the end code of one frame of data whose value is limited to 0 Xfe. When the receiving end receives the frame end, the receiving end indicates that the receiving of one frame of data is completed. The complete structure of the frame of data is ADDRESS, ASCII 0- -ASCII 12 and QUEUE. When each digital welding Device is used as a receiving end, the data of the frame received from the RS485 bus is firstly compared to judge whether the ADDRESS is the same as the Device ADDRESS _ ID of the digital welding Device, if the ADDRESS is not the same as the Device ADDRESS _ ID of the digital welding Device, the data is discarded, if the ADDRESS is the same as the Device ADDRESS _ ID of the digital welding Device, ASCII 0-ASCII 12 is decoded into BYTE 1-BYTE 5 and a check code CHECKSUM through operation D, BYTE 1-BYTE 5 are compared with the check code CHECKSUM through operation D, if the two check codes are different, the data of the frame is discarded, and if. If so, BYTE 1-BYTE 5 is received. The digital power source acts as a sink and differs from each digital welding device in that the digital power source distinguishes which digital welding device originated based on the frame start ADDRESS, and if the ADDRESS is not 0Xf 0-0 Xfd, the frame data is an error. The G operation is characterized in that a programmer can arbitrarily define the operation G to verify data.

It is understood that the digital power source sends a query command beginning with the device address of each digital welding device in the sending time slot, and all digital welding devices accessing the system through the RS485 bus are searched through addressing.

It will be appreciated that after the digital power source sends a query command beginning with the device address of each digital welding device, the digital welding device, receiving the inquiry instruction sent by the digital power supply through a preset RS485 bus communication protocol, when the device address transmitted by the digital power source matches the device address of a digital welding device, the digital welding equipment with the same equipment address filters the data sent by the digital power supply, after the digital welding equipment successfully receives the data, the digital welding equipment sends response information with the equipment address as the frame head to the digital power supply, the digital power supply receives the response message and compares its device address with the device address in the transmitted query command, and when the data is consistent with the data, the digital welding equipment is identified to be communicated with the digital power supply through the RS485 bus by considering that a correct response is received.

S40: and the digital power supply establishes communication connection with each digital welding device respectively when receiving response information of each digital welding device with the device address as the frame head.

It should be noted that the digital power source receives the reply with the same device address as the inquiry command as the frame head in the receiving time slot, and if the digital welding device corresponding to the device address does not exist, the reply is not obtained in the receiving time slot. If the digital power supply does not receive the correct responses of the digital welding devices in the receiving time slots, the digital power supply cannot establish communication connection with the digital welding devices respectively. When the digital power source receives a correct response sent by a digital welding device, the digital power source establishes a communication connection with the digital welding device that sent the correct response.

It should be understood that the frame head ADDRESS of the frame data structure, which is both the ADDRESS and the synchronization code of a device, is represented by a 16-ary frame head code, and its value is limited to 0Xf 0-0 Xfd, the digital power source uses the device ADDRESS as the frame head, the frame head starts to be transmitted as the frame head code, each digital welding device starts to receive the frame head synchronization, and compares the frame head transmitted by the digital power source with the device ADDRESS of each digital welding device, and when the frame head transmitted by the digital power source is consistent with the device ADDRESS of one digital welding device, the digital welding device with the same device ADDRESS filters out the data transmitted by the digital power source and identifies that the digital welding device establishes a communication connection with the digital power source.

In the embodiment, a set of preset RS485 bus communication protocol is designed to establish communication connection between the digital power supply and each welding device, so that the digital power supply and each welding device are strong in communication anti-interference performance, high in reliability, simple, convenient and economical.

Referring to fig. 7, a second embodiment of a method for communicating a digital power source with a plurality of digital welding devices of the present invention is presented based on the first embodiment of the method for communicating a digital power source with a plurality of digital welding devices described above.

In this embodiment, after the step S40, the method further includes:

s50: when the digital power supply is electrified and initialized, a first preset type inquiry instruction is sent to each digital welding device in turn;

it can be understood that the preset RS485 bus communication protocol is divided into a data conversion layer and an application management layer, and the application management layer is divided into digital power supply application management and digital welding equipment application management. The welding power source protocol is as follows: in the standby state, all digital welding devices accessed to the system through the 485 bus are searched through addressing. For the digital power supply, the signal on the RS485 bus is divided into a transmit time slot and a receive time slot. The sending time slot sends a query instruction with the equipment address of each digital welding equipment as the frame head, the receiving time slot receives response information with the same equipment address as the frame head, and if the digital welding equipment corresponding to the equipment address does not exist, the response information cannot be obtained in the receiving time slot. The queries issued by the digital power supply are of 4 different types, identified by frame type identifiers. Referring to the one-frame data structure diagram of fig. 2, the data structure for each type of query instruction is detailed as follows:

frame 0: the frame signal is transmitted during the welding process, and the structure is as follows,

the frame header is the device address; the lower three bits bit 0-bit 2 of BYTE1 identify Frame0, bit3 of BYTE1 for standby, bit4 and bit5 of BYTE1 transmit the lower two bits of welding voltage, and bit6 and bit7 of BYTE1 transmit the lower two bits of welding current; BYTE2 carries the remaining upper 8 bits of welding current; BYTE3 carries the remaining upper 8 bits of the welding voltage; BYTE4 conveys the wire feed speed of the wire feeder during welding; BYTE5 conveys various states during welding; followed by a frame checksum and an end of frame.

Frame 1: the frame signal is sent in the gas detection process, and the structure is as follows,

the frame header is the device address; the lower three bits bit 0-bit 2 of BYTE1 identify Frame1, bit3 of BYTE1 for standby, bit4 and bit5 of BYTE1 transmit the lower two bits of welding voltage, and bit6 and bit7 of BYTE1 transmit the lower two bits of welding current; BYTE2 carries the remaining upper 8 bits of welding current; BYTE3 carries the remaining upper 8 bits of the welding voltage; BYTE4 conveys the wire feed speed of the wire feeder during welding; BYTE5 conveys gas flow during gas detection; followed by a frame checksum and an end of frame.

Frame1 differs from Frame0 in the Frame type identifier and BYTE5, BYTE5 carries the gas flow during the gas detection process.

Frame 2: the frame signal is transmitted in a standby state, and has a structure as follows,

the frame header is the device address; the lower three bits bit 0-bit 2 of BYTE1 identify Frame2, bit3 of BYTE1 for standby, bit4 and bit5 of BYTE1 transmit the lower two bits of welding voltage, and bit6 and bit7 of BYTE1 transmit the lower two bits of welding current; BYTE2 carries the remaining upper 8 bits of welding current; BYTE3 carries the remaining upper 8 bits of the welding voltage; BYTE4 conveys the wire feed speed of the wire feeder during welding; BYTE5 conveys gas pressure during gas detection; followed by a frame checksum and an end of frame.

Frame2 differs from Frame0 in that the Frame type identifier and BYTE5, BYTE5 convey the pressure of the gas during the gas detection process.

Frame 3: the frame signal is transmitted in a standby state, and has a structure as follows,

the frame header is the device address; the lower three bits bit 0-bit 2 of BYTE1 identify Frame3, bit3 of BYTE1 for standby, bit4 and bit5 of BYTE1 transmit the lower two bits of welding voltage, and bit6 and bit7 of BYTE1 transmit the lower two bits of welding current; BYTE2 carries the remaining upper 8 bits of welding current; BYTE3 carries the remaining upper 8 bits of the welding voltage; BYTE4 conveys the wire feed speed of the wire feeder during welding; BYTE5 conveys the real-time alert code of the system; followed by a frame checksum and an end of frame.

Frame3 differs from Frame0 in that the Frame type identifier and BYTE5, BYTE5 convey the real-time alarm code of the system.

It should be noted that, as shown in fig. 4, fig. 4 is a signal flow chart of the digital power source sending signals to each digital welding device, and the first preset type query command is: frame0, Frame1, Frame2, and Frame 3. When the system is powered on and initialized, the digital power supply wheel sends inquiry commands of Frame0, Frame1, Frame2 and Frame3 to each digital welding device in turn.

The digital power supply is also used for receiving first type response information sent by each digital welding device, and enters a standby state when the number of times of the received first type response information exceeds a preset number of times;

s60: when the digital welding equipment is electrified and initialized, receiving a first preset type inquiry instruction sent by the digital power supply, and sending first type response information to the digital power supply;

it will be appreciated that, at power-on initialization, the digital welding device, upon receiving a first preset type of query command sent by the digital power source in turn: frame0, Frame1, Frame2, and Frame3, first type response information is transmitted to the digital power supply: frame 0.

S70: the digital power supply receives first type response information sent by each digital welding device, and enters a standby state when the number of times of receiving the first type response information exceeds a preset number of times.

It should be understood that the digital welding device sends the response message in 7 different types, identified by frame type identification. Referring to the structure diagram of one frame data of fig. 2, the data structure of each type of response message is detailed as follows:

frame 0: this frame signal transmits software and hardware version information of the digital welding apparatus, which is structured as follows,

the frame head is the equipment address of the digital welding equipment; the low 4 bits bit 0-bit 3 of BYTE1 identify Frame0, bits 4-bit 7 of BYTE1 stand-by, BYTE2 transfers the hardware version of the digital welding device, BYTE2 transfers the software version of the digital welding device, BYTE4 stands-by, BYTE5 stands-by, followed by Frame checksum and Frame trailer.

Frame 1: this frame of signals, which is responsive to the digital power source interrogation when the digital power source and the digital welding devices enter a welding state, is configured as follows,

the frame head is the equipment address of the digital welding equipment; the low 4 bits bit 0-bit 3 of BYTE1 identify Frame1, bit 4-bit 6 of BYTE1 are spare, bit7 of BYTE1 is a starting switch of a digital power supply as a starting signal, namely, a torch switch (torch push button) equivalent to a welding machine; BYTE2 transmits the MAIN high 8-bit MAIN SETH of the digital power supply; BYTE3 carries the MAIN low 8-bit MAIN SETL of the digital power supply; BYTE4 transmits the secondary high 8-bit SECOND SETH of the digital power supply; BYTE5 delivers a secondary low 8-bit SECOND SETL of the digital power supply; followed by a frame checksum frame trailer;

by MAIN SET is meant: MAIN SET is the welding current setting when the welding mode is unitary (sine) or pulse (pulse) or double pulse (double pulse); MAIN SET is the welding voltage setting when the welding mode is Standard (Standard) mode; by SECOND SET is meant: SECOND SET is the welding arc length setting when the welding mode is unitary (sine) or pulse (pulse) or double pulse (double pulse); SECOND SET is the welding wire feed speed setting when the welding mode is Standard (Standard) mode; when MAIN SET is 0, SECOND SETL is disabled, and the parameters of the digital power source are given to Frame3 for setting.

Frame 2: this frame of signals, which is responsive to interrogation of the digital power source when the digital power source and the digital welding devices enter a sensing state, is configured as follows,

the frame head is the equipment address of the digital welding equipment; the low 4 bits bit 0-bit 3 of BYTE1 identify Frame2, bit 4-bit 7 of BYTE1 for standby; bit7 and bit6 of BYTE2 are reserved; bit5 gas detection switch (gas test); bit4 air blow switch (aria test); bit3 wire feed (motor forward continuous); bit2 drawstring (motor back coiled continuous yarn); bit1 fixed length wire feed (motor step forward); bit0 fixed length drawing (motor step backward); BYTE3 is given for wire feed speed when BYTE2 bit3 or bit2 or bit1 or bit0 is 1; BYTE4 gives the upper 8 bits for a given wire feed length when bit1 or bit0 of BYTE2 is 1; BYTE5 gives the lower 8 bits for the wire feed length when bit1 or bit0 of BYTE2 is 1; followed by a frame checksum and an end of frame.

Frame 3: the frame signal is used for responding to the inquiry of the digital power supply when the system is in a standby state, and the structure is as follows,

the frame head is the equipment address of the digital welding equipment; the low 4 bits bit 0-bit 3 of BYTE1 identify Frame3, bit 4-bit 7 of BYTE1 for standby; BYTE2 welding program number (program of welding); BYTE3 weld JOB number (JOB number); BYTE4 for later use; BYTE5 for later use; followed by a frame checksum and an end of frame.

When the BYTE3 welding JOB number (JOB number) of the Frame3 is set to 0, the subsequent frames 4, 5, 6 and 7 are required to set and send response information to the digital power supply, otherwise, the frames 4, 5, 6 and 7 are invalid.

Frame4, Frame5, Frame6, and Frame 7: these 4 frames are signals for responding to the inquiry of the digital power supply when the system is in a standby state and the job number is set to 0, and are structured as follows,

frame 4: the low 4 bits bit 0-bit 3 of BYTE1 identify Frame4, bit 4-bit 7 of BYTE1 for standby; BYTE2 welding mode: 1 manual gas shield welding (mig manual), 2 unified gas shield welding (mig synergy), 3 single pulse welding (mig pulse), 4 double pulse welding (mig double), 11 welding rod welding (stick), 12 argon arc welding (tig) and 13 carbon arc gas gouging (arc); BYTE3slope up (current ramp up); BYTE4I start (starting current); BYTE5t start (arc start time); followed by a frame checksum and an end of frame.

Frame 5: the low 4 bits bit 0-bit 3 of BYTE1 identify Frame5, bit 4-bit 7 of BYTE1 for standby; BYTE2 slopdo (current ramp down); BYTE3I stop (arc strike current); BYTE4t stop (arc time); BYTE5start lift; followed by a frame checksum and an end of frame.

Frame 6: the low 4 bits bit 0-bit 3 of BYTE1 identify Frame6, bit 4-bit 7 of BYTE1 for standby; BYTE2hot start (hot start); BYTE3 inductance; BYTE4bbt (burn-back time); BYTE5pregas (forward blow);

followed by a frame checksum and an end of frame.

Frame 7: the low 4 bits bit 0-bit 3 of BYTE1 identify Frame7, bit 4-bit 7 of BYTE1 for standby; BYTE2double frequency (double pulse frequency); BYTE3balance (double pulse peak base duty cycle); BYTE4I low (base current); BYTE5 for later use; followed by a frame checksum and an end of frame.

It should be noted that, during initialization of the welding system, the digital power wheel sends a first type query command for Frame0, Frame1, Frame2, and Frame3 to each digital welding device in turn, and each digital welding device responds to Frame0, that is, the first type response information is Frame 0. The preset number is a self-defined polling number, which may be 10 times, or may be set to another value, which is not limited in this embodiment. And the digital power supply sends the first type inquiry command to each digital welding device for 10 times in turn, and when the digital power supply receives the correct response of the Frame0 of each digital welding device for 10 times in a receiving time slot and the equipment states of the digital power supply and each digital welding device are normal, the digital power supply and each digital welding device enter a standby state, otherwise, the digital power supply and each digital welding device enter an alarm state.

In this embodiment, after the step S70, the method further includes:

s80: the digital power supply sends a first preset type inquiry instruction to each digital welding device in turn in the standby state;

it should be appreciated that in the standby state, the digital power supply alternately sends a first preset type of query to each digital welding device: frame0, Frame1, Frame2, and Frame 3.

S90: and the digital welding equipment receives a first preset type inquiry instruction sent by the digital power supply and sends second type response information to the digital power supply in the standby state.

It will be appreciated that, in the standby state, the digital welding device receives a first preset type of query command sent by the digital power supply: frame0, Frame1, Frame2, and Frame3, and when JOB NUMBER is equal to 0, transmits second type response information: frame1, Frame2, Frame3, Frame4, Frame5, Frame6 and Frame7 to the digital power source, when the JOB NUMBER is not equal to 0, the second type of response information is sent: frame1, Frame2, Frame3 to the digital power supply.

S100: and the digital power supply receives second type response information sent by each digital welding device, and enters a welding state when the second type response information comprises a welding machine starting signal.

It is understood that when the JOB NUMBER of the communication system of the digital power source and the plurality of digital welding devices is equal to 0, the parameters of the communication system are given by each digital welding device, and the second type of response information that each digital welding device responds to is Frame1, Frame2, Frame3, Frame4, Frame5, Frame6, and Frame 7. When the JOB NUMBER is not equal to 0, the parameters of the communication system are given by various JOBs set by the digital power supply and are called by JOB NUMBER in Frame 3in the response information of each digital welding device. The digital power supply sends Frame0, Frame1, Frame2 and Frame3 to each digital welding device in turn, and at the moment, the second type response information is as follows: frame1, Frame2, Frame 3.

It should be understood that when the torch switch of the Frame1 received by the digital power supply in the response message of each digital welding device in the receiving time slot is 1, the digital power supply and each digital welding device enter the welding state, and enter the alarm state if an abnormality occurs.

In this embodiment, the digital power supply is further configured to enter a test state when each switch signal in the received second type response information is first preset data in the standby state.

It is to be understood that when the digital power source receives, at a receive time slot, one and only one of the respective switch signals in the BYTE2 of the Frame2 in the reply message for each digital welding device is a 1, the digital power source and each digital welding device enter a test state. The customized first preset data is that one and only one of the switch signals in the BYTE2 of the Frame2 is 1.

In the embodiment, by designing the structure and the communication rule of the communication data between the welding power supply and each digital welding device, when the preset rule is met, the digital power supply and each digital welding device exit from the test state and enter the corresponding standby state or welding state, so that the effective communication between the welding power supply and each digital welding device is realized, and the communication is convenient and fast and has high reliability.

Referring to fig. 8, a third embodiment of a method for communicating a digital power source with a plurality of digital welding devices of the present invention is presented based on the second embodiment of the method for communicating a digital power source with a plurality of digital welding devices described above.

In this embodiment, after the step S100, the method further includes:

step S110: the digital power supply sends a second preset type inquiry instruction to each digital welding device in turn in the welding state;

it should be appreciated that in the welding state, the digital power supply alternately sends a second preset type of query command to each digital welding device: frame 0.

Step S120: the digital welding equipment receives a second preset type inquiry instruction sent by the digital power supply in the welding state and sends third type response information to the digital power supply;

it should be noted that, in the welding state, the digital welding device receives a second preset type query command sent by the digital power supply: frame0, a third type of response message is sent to each digital welding device': frame 1.

Step S130: and the digital power supply receives third type response information sent by each digital welding device, and enters a standby state when the third type response information comprises a welding machine closing signal.

It will be appreciated that the third type of response message for each digital welding device is: frame 1. When the digital power supply receives that the torch switch in the response information Frame1 of each digital welding device is 0 in the receiving time slot, that is, receives a welding machine closing signal, the digital power supply and each digital welding device exit the testing state, exit the welding state and enter the standby state. And if the abnormity occurs, entering an alarm state.

In the embodiment, by designing the structure and the communication rule of the communication data between the welding power supply and each digital welding device, when the preset rule is met, the digital power supply and each digital welding device quit the welding state and enter the corresponding standby state, so that the effective communication between the welding power supply and each digital welding device is realized, and the communication is convenient and fast and has high reliability.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or system. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or system that comprises the element.

The above-mentioned serial numbers of the embodiments of the present invention are merely for description and do not represent the merits of the embodiments.

The usage of the words first, second, third, etcetera herein does not indicate any ordering. These words may be interpreted as names.

Through the above description of the embodiments, those skilled in the art will clearly understand that the method of the above embodiments can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware, but in many cases, the former is a better implementation manner. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium (e.g., ROM/RAM, magnetic disk, optical disk) as described above and includes instructions for enabling a terminal device (e.g., a mobile phone, a computer, a server, an air conditioner, or a network device) to execute the method according to the embodiment of the present invention.

The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the information in the specification and drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.