CN110936070B

CN110936070B - Welding line double-clamp switching control method

Info

Publication number: CN110936070B
Application number: CN201911219769.1A
Authority: CN
Inventors: 吕长亮; 汉俊梅; 杜俭状; 王晓峰; 李超
Original assignee: FAW Group Corp; Faw Tooling Die Manufacturing Co Ltd
Current assignee: FAW Group Corp; Faw Tooling Die Manufacturing Co Ltd
Priority date: 2019-12-03
Filing date: 2019-12-03
Publication date: 2021-06-11
Anticipated expiration: 2039-12-03
Also published as: CN110936070A

Abstract

The invention belongs to the technical field of automobile body-in-white welding, and relates to a double-clamp switching control method of a welding line; the core module of the hardware system is formed by depending on related hardware of a Siemens SINAMICS S120 drive system, the connection of more network types and wider application range are realized by changing some parts in the core component, and a function block suitable for programming software Step7 is developed corresponding to the core component of the hardware system, so that the function of the dual-clamp switching control system is realized; the method comprises the following steps: 1. judging whether the connection communication between the core module and the external network is normal or not; 2. judging whether the external operation condition is met; 3. judging whether the related status word is received normally; 4. selecting a mode; selecting a positioning mode and an adjusting mode; 5. judging whether the operation conditions are met; 6. starting operation; the invention can meet the switching drive requirement of all clamps from the splitting line to the main welding line of the welding production line; the software control standardization is realized, and the software development period is reduced.

Description

Welding line double-clamp switching control method

Technical Field

The invention belongs to the technical field of automobile body-in-white welding, and relates to a double-clamp switching control method for a welding line.

Background

At present, the double-clamp switching control system of the white automobile body welding production line is increasingly widely applied, and a plurality of related control technologies are derived. However, although various control technologies can achieve the same function, there is no software and hardware modularization development, resulting in a similar control mode of the clamp switching system, which is a five-door, and brings great pressure on the aspects of maintenance, spare part management and the like of the production line in the later period.

In the field of welding and manufacturing of automobile bodies in white, only one type of automobile can be produced by one welding line, and the history is already available, and the flexible production of multiple types of automobiles in the production line is already the mainstream. In order to meet the flexible production of various vehicle types of welding lines, the application of the same-station double-clamp and even multi-clamp switching system is increasingly wide, and a plurality of related control technologies are derived.

At present, a double-clamp switching control system of a white automobile body welding production line has a similar scheme.

The welding equipment is a standardized hardware and software module similar to that developed by mass automobiles for various driving systems of a welding production line, wherein related function blocks suitable for the popular welding VASS standard are developed in the aspect of software through the use of SEW series frequency converters and motors in the hardware system, and the driving functions of clamps or other equipment are realized. However, the standardized development of the hardware and the software aims at the VASS standard of the popular welding shop, and the hardware and the software cannot be used in other standard welding shops or nonstandard welding shops.

One is a welding workshop of other host factories with imperfect standards or no standards, no standards exist in hardware integration and software development, and the realization of related functions depends on hardware purchase and program writing of technicians of various suppliers. However, in terms of cost in hardware, the brand models and the interface types of each component are all five-door, and in terms of software, the function can be realized by writing program statements, the form is also strange, great challenges are brought to maintenance and spare part management of later-stage related equipment of a wire body, and the possibility of large-scale popularization and use is certainly not provided.

Disclosure of Invention

The invention provides a welding line double-clamp switching control method for solving the problems in the prior art. The invention provides a hardware modularization and software modularization scheme of the double-clamp switching system, thereby realizing the standardized development of the double-clamp switching system. The hardware aspect is modularly constructed, and the software aspect is developed for related functional blocks, so that modularization and standardization of the double-clamp switching control system are realized.

In order to solve the technical problems, the invention is realized by adopting the following technical scheme, which is described by combining the accompanying drawings as follows:

the invention relies on the relevant hardware of the Siemens SINAMICS S120 drive system to form a core module of a hardware system, realizes more network type connection and wider application range by changing some parts in the core component, develops a function block suitable for programming software Step7 corresponding to the core component of the hardware system, and realizes the function of a double-clamp switching control system.

A welding line double-clamp switching control method comprises the following steps:

the method comprises the following steps: judging whether the connection communication between the core module and the external network is normal or not; inputting an external network monitoring signal, and judging whether the connection between the external network and the core module is normal or not; if the connection communication is normal, the external PLC starts to send the corresponding bit of the relevant control word to the internal core module, namely: selecting an external PLC for control, selecting a continuous receiving set value and selecting a connecting motor;

step two: judging whether the external operation condition is met; whether the external communication equipment is suddenly stopped or other alarms are carried out, whether a core module has error reporting information feedback is carried out, if yes, corresponding positions of related control words are immediately output, quick stopping is realized, a frequency converter is forbidden, program operation is cancelled, operation performance is closed, quick stopping of a driving unit is realized, and related alarm information is output so as to quickly lock a fault position;

step three: judging whether the related status word is received normally; after the network connection is normal, no external and internal alarm exists, and the external PLC sends out the corresponding control word, the external PLC receives the corresponding bit of the relevant status word sent by the core module under normal conditions, that is: the core module is ready to be switched on, and the frequency converter has no alarm error;

step four: selecting a mode; there are two kinds of external mode input, namely positioning mode and adjustment mode selection; the positioning mode is a control operation mode, and the adjusting mode is a manual adjusting operation mode;

step five: judging whether the operation conditions are met; and starting to judge the operation conditions under the selection condition of the positioning mode, wherein the operation conditions comprise that a reference point is set, a soft limit position is not reached, a safety distance switch is not triggered, a target position is not reached, and the target position is not occupied.

Step six: starting operation; the manual or automatic control mode of the external PLC is selected, and the PLC can operate by starting a button command. Note that the manual mode is selected and the direction of travel of the clamp needs to be selected prior to activation.

And step five, the target position reaches the data processing and operation needing to be processed by the position code value, and the details are as follows:

"leftward movement target position input value": according to the actually required working position, adjusting the position code value of the leftwards moving target tested by the mode;

"rightward movement target position input value": reference value, i.e. point 0;

"error allowance value"; when a certain position is reached, the allowed difference value of the target code value and the actual code value is obtained;

"actual position value": feeding back the actual code value of the driving mechanism of the external PLC through the state word;

"target position difference": an absolute value of "leftward movement target position input value" - "actual position value" or "rightward movement target position input value" - "actual position value";

when { ("actual position value" - "leftward movement target position input value") < "error allowance value" } and ("target position difference" < "error allowance value") — move leftward into position;

when { ("actual position value" - "rightward movement target position input value") < "error allowance value" } and ("target position difference" < "error allowance value") —) -moving rightward to a position;

the target position of the other drive mechanism is exactly opposite, namely:

"rightward movement target position input value": according to the actually required working position, adjusting the position code value of the leftwards moving target tested by the mode;

"leftward movement target position input value": reference value, i.e. point 0.

Compared with the prior art, the invention has the beneficial effects that:

compared with the prior art, the power and current coverage of the hardware power supply module and the control module is wide, and the switching driving requirements of all clamps from the split line to the main welding line of the welding production line can be met; in the aspect of software, complex logic writing is avoided through development of corresponding function blocks, a user only needs to fill in corresponding pins, software control standardization is achieved, non-standardization of software development is avoided, and the period of software development is greatly reduced.

Drawings

The invention is further described with reference to the accompanying drawings in which:

fig. 1 is a schematic diagram of hardware connections.

FIG. 2 is a flow diagram of program function blocks.

Detailed Description

The invention is described in detail below with reference to the attached drawing figures:

the invention realizes the function of the welding line double-clamp switching control system through hardware design and software programming and through the standardized development of the software and the hardware, and the specific contents are as follows:

hardware modularization: the Siemens SINAMICS S120 drive system relevant hardware is taken as a basic component, and the Siemens 89120 drive system relevant hardware comprises five core components such as a control module, a power supply module, a double-motor control module, a brake module and a motor. Referring to fig. 1, the core module is a hardware component for hardware standardization. The functions of each core module are as follows:

1. a control module: the brain of the drive system is responsible for controlling and coordinating all modules in the whole system.

2. A power supply module: the rectifier module rectifies the three-phase alternating current into direct current to be supplied to the motor module. It is divided into basic type, intelligent type and active type.

3. The double-motor module: the inverter unit is used for inverting 540V or 600V direct current into three-phase alternating current and can simultaneously drive two motors to operate.

4. A brake module: i.e. a braking resistor, for absorbing energy during braking.

5. A motor: the driving device and the power source for the movement of the mechanical system.

In order to use the hardware module more widely, hardware selection can be carried out on part of the modules according to actual use requirements. The method comprises the following steps: the control module supports two bus communication protocols of PROFIBUS and PROFINET; the power of the power supply module ranges from 5KW to 120 KW; the rated current range of the dual-motor control module is 2 multiplied by 3A to 2 multiplied by 18A, so the application range of the hardware system is wider, and the load requirements of all dual-clamp switching systems of a welding line can be almost met.

Besides the core module, other auxiliary equipment and cables are provided, and the user can select the auxiliary equipment and the cables according to actual use conditions.

Secondly, software modularization: the software modularization mainly comprises three parts:

1. fixed message structure: appropriate control word and status word transmission forms-111 messages;

2. a data structure (UDT) and a network communication function block (FB283 block) based on the fixed message structure;

3. on the basis of the above two conditions, a program function block and a corresponding function method suitable for step7 software are developed to satisfy the dual-clamp switching operation.

The first two items have mature developed products, and the software modularization is mainly used for developing the third item on the basis of the first two items. FIG. 2 is a flow diagram of program function blocks. Referring to fig. 2, the functions and method contents of the program function block mainly include the following steps:

1. judging whether the connection communication between the core module and the external network is normal: here, the external network monitoring signal is required to be input to determine whether the connection between the external network and the core module is normal. If the connection communication is normal, the external PLC starts to send the corresponding bit of the relevant control word to the internal core module, namely: selecting an external PLC for control, selecting a continuous receiving set value and selecting a connecting motor.

2. Judging whether the external operation conditions are met: whether the external communication equipment is suddenly stopped or other alarms or not, whether the core module has error reporting information feedback or not are mainly included, if yes, the corresponding position of the related control word is immediately output, quick stopping is realized, the frequency converter is forbidden, program operation is cancelled, operation performance is closed, quick stopping of the driving unit is realized, and meanwhile, related alarm information is output so that the fault position can be quickly locked.

3. Judging whether the relevant state word is received normally: after the network connection is normal, no external and internal alarm exists, and the external PLC sends out the corresponding control word, the external PLC receives the corresponding bit of the relevant status word sent by the core module under normal conditions, that is: the core module is ready to be switched on, and the frequency converter has no errors such as alarm and the like.

The above stages complete the basic communication and signal interaction between the external PLC and the core module, and lay the foundation for the following actual drive.

4. A mode selection section: this step is mainly input by 2 external modes, namely, a positioning mode and an adjustment mode. The positioning mode is a control operation mode, and the adjusting mode is a manual adjusting operation mode. After the adjustment mode is selected, the manual mode is correspondingly selected and the motion button is activated, so that the device can freely move under the safe condition that positive and negative soft limit is not reached, and the device is usually used for selection and setting of various positions in the early debugging process, position test of interference and the like.

5. Judging whether the operation conditions are met: and starting to judge the running conditions under the selection condition of the positioning mode, wherein the running conditions comprise conditions of whether a reference point is set, whether a soft limit position is judged, whether a safe distance switch is triggered, whether a target position is reached, whether a target position occupies the space and the like, after the conditions all meet the requirements, the MDI mode (the running mode for realizing the positioning function through the control of an external PLC) is started, the enabling is switched on, all the preconditions for the running of the driver are met at the moment, the driving unit is powered on, and only the external PLC mode is waited and the running command is started.

The data processing and operation that the target position reaches and needs to pass through the position code value are detailed as follows:

"rightward movement target position input value": reference value, i.e. point 0.

"error allowance value"; when a certain position is reached, the target code value and the actual code value are allowed to be different.

"target position difference": the absolute value of the "leftward movement target position input value" - "actual position value" or the "rightward movement target position input value" - "actual position value".

When { ("actual position value" - "leftward movement target position input value") < "error allowance value" } and ("target position difference" < "error allowance value") — move leftward into position.

When { ("actual position value" - "rightward movement target position input value") < "error allowance value" } and ("target position difference" < "error allowance value") -moving right to place.

The target position of the other drive mechanism is exactly opposite, namely:

"leftward movement target position input value": reference value, i.e. point 0.

6. Starting and operating: the step can select the manual or automatic control mode of the external PLC, and in the manual mode, the running direction needs to be selected,

and the operation can be realized by selecting the starting button.

On the premise of building the hardware module, a 111 message structure of a Siemens S120 driving system and two function blocks developed based on step7 software are used, the two function blocks internally contain contents such as logic operation, alarm and function display, external condition input and the like in the motion process of the double-clamp switching system, the switching function standardization of the double-clamp system can be realized, and the high-practicability system has high practical value.

The method meets the flow and function requirements of the double-clamp switching system, and can be suitable for the logic operation requirements of the double-clamp switching system.

Claims

1. A welding line double-clamp switching control method is characterized by comprising the following steps:

step two: judging whether the external operation condition is met; whether the external communication equipment is suddenly stopped or other alarms are carried out, whether a core module has error reporting information feedback is carried out, if yes, corresponding positions of related control words are immediately output, quick stopping, forbidding of a frequency converter and program operation cancellation are realized, operation performance is closed, quick stopping of a driving unit is realized, and related alarm information is output simultaneously so as to quickly lock a fault position;

step five: judging whether the operation conditions are met; under the selection condition of the positioning mode, starting to judge the operation conditions, wherein the operation conditions comprise that a reference point is set, a soft limit position is not reached, a safe distance switch is not triggered, a target position is not reached, and the target position is not occupied;

step six: starting operation; the manual or automatic control mode of the external PLC is selected, and the PLC can run by starting a button command; it should be noted that the manual mode is selected, and before starting, the running direction of the clamp needs to be selected;

the target position of the other drive mechanism is exactly opposite, namely:

"leftward movement target position input value": reference value, i.e. point 0.