JP7296115B2 - Resistance welding system and its control method and control program - Google Patents

Description

The present invention relates to a resistance welding system, its control method, and control program.

A resistance welder sandwiches metals to be welded (hereinafter referred to as "work") between welding electrodes (hereinafter referred to as "electrodes"), and applies current from the electrodes while applying pressure. A resistance welder melts a workpiece to be welded by resistance heat (Joule heat) generated by the application of electric current to form a point-like weld (hereinafter referred to as a "nugget") at the welding location.

In resistance welding, welding conditions are selected according to the type of workpiece to be welded (for example, the type of metal, thickness, etc.) so that an appropriate nugget can be formed. For example, in resistance welding, the conditions such as the pressure applied to the workpiece by the electrode, the current waveform, the current value, or the current application time are selected according to the workpiece. In a conventional resistance welder, for example, a current waveform such as a rectangular waveform, an upslope waveform, or a downslope waveform can be selected as a welding waveform (see, for example, Patent Document 1).

Further, in the conventional resistance welder, it was possible to select the pressure applied to the work as the welding condition. Resistance welders maintain a constant applied force during welding at a selected force. The pressurizing force can be kept constant by adjusting the driving force of air pressure or a motor, for example.

Japanese Patent Application Laid-Open No. 2007-210006

However, in recent years, welding of ultra-high-strength steel sheets of 1180 MPa or higher, steel sheets formed by hot pressing, non-ferrous metals such as aluminum alloy sheets, magnesium alloy sheets, titanium alloy sheets, or steel sheets with various platings has been introduced. The types of target workpieces are increasing. Therefore, in some cases, optimum welding cannot be performed only with the welding conditions that can be set in the conventional resistance welder.

The present invention has been made in view of the above circumstances, and aims to provide a resistance welding system, its control method, and a control program that can easily set suitable welding conditions according to the types of various workpieces. one purpose.

(1) In order to solve the above problems, the resistance welding system includes a UI providing unit that provides a user interface (UI) for the user to input drawing data, and a UI provided in the UI providing unit. a drawing data acquisition unit that acquires drawing data input by a user through the drawing data acquisition unit; a waveform generation unit that generates waveform data used in resistance welding based on the drawing data acquired by the drawing data acquisition unit; and an output unit for outputting the generated waveform data.

(2) In addition, in the resistance welding system of the embodiment, the waveform generation unit generates current waveform data of the current applied to the workpiece in resistance welding based on the drawing data as the waveform data, and the output unit generates the waveform. The current waveform data generated in the part may be output to the resistance welding part where resistance welding is performed.

(3) In addition, in the resistance welding system of the embodiment, the waveform generation unit generates pressure waveform data of the pressure applied to the workpiece in resistance welding based on the drawing data as the waveform data, and the output unit The pressurizing force waveform data generated by the waveform generator may be output to the pressurizer that presses the workpiece.

(4) In addition, in the resistance welding system of the embodiment, when the user inputs drawing data, the UI providing unit displays the waveform data generated by the waveform generating unit according to the input of the drawing data. may be provided.

(5) In addition, the resistance welding system of the embodiment further includes a waveform value acquisition unit that acquires waveform values suitable for welding, and the waveform generation unit calculates the effective value of the generated waveform data, and further calculates the effective value of the calculated waveform data. A conversion ratio is calculated for conversion so that the effective value and the waveform value acquired by the waveform value acquisition unit are equal, and the output unit outputs the conversion ratio calculated by the waveform generation unit. good.

(6) Moreover, the resistance welding system of the embodiment may further include a communication control unit that controls communication with a server connected via a network.

(7) Further, in the resistance welding system of the embodiment, the communication control section may provide the waveform data generated by the waveform generation section to the server.

(8) Further, in the resistance welding system of the embodiment, the communication control unit obtains waveform data stored in the server from the server, and the UI providing unit edits the waveform data obtained from the server and generates drawing data. It may provide a UI for input.

(9) In addition, in the resistance welding system of the embodiment, the UI providing unit displays a coordinate system in which a plurality of points can be plotted, and plots the plurality of points plotted against the displayed coordinate system by the user as drawing data. and the waveform generator may generate waveform data obtained by smoothing a plurality of points of the drawing data obtained by the drawing data obtaining unit.

(10) Further, in the resistance welding system of the embodiment, the UI providing unit movably displays at least one of the plurality of points within the coordinate axes, and the waveform generating unit displays the point moved by the user. The waveform data may be regenerated based on.

(11) In order to solve the above problems, the resistance welding system control method is a resistance welding system control method, which provides a user interface (UI) for the user to input drawing data. a drawing data obtaining step of obtaining drawing data input by a user via the UI provided in the UI providing step; and a waveform used in resistance welding based on the drawing data obtained in the drawing data obtaining step. It includes a waveform generation step of generating data and an output step of outputting the waveform data generated in the waveform generation step.

(12) In order to solve the above problems, the control program of the resistance welding system includes a UI providing function for providing a user interface (UI) for the user to input drawing data to the computer, and a UI providing function A drawing data acquisition function that acquires drawing data input by the user via the provided UI, and a waveform generation function that generates waveform data used in resistance welding based on the drawing data acquired by the drawing data acquisition function. and an output function for outputting the waveform data generated by the waveform generation function.

According to one embodiment of the present invention, a user interface (UI) is provided for a user to input drawing data, and the drawing data input by the user is obtained through the provided UI. By generating waveform data used in resistance welding based on the drawn data and outputting the generated waveform data, it is possible to easily set appropriate welding conditions for various types of workpieces. .

It is a block diagram showing an example of software composition of a resistance welding system in an embodiment. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows an example of the outline|summary of the resistance welding system in embodiment. It is a flow chart which shows an example of operation of a resistance welding system in an embodiment. It is a figure which shows an example of the current drawing data input in UI which the resistance welding system in embodiment provides. It is a figure which shows an example of the current waveform data display in UI which the resistance welding system in embodiment provides. It is a figure which shows an example of (A) current waveform data and (B) conversion ratio which the resistance welding system in embodiment outputs. It is a figure which shows another example of the current waveform data which the resistance welding system in embodiment outputs. It is a figure which shows an example of the welding current of the resistance welding system in embodiment, and the characteristic of a nugget diameter. FIG. 7 is a diagram showing another example of the characteristics of the welding current and nugget diameter of the resistance welding system in the embodiment; It is a figure which shows an example of the weld lobe of the resistance welding system in embodiment. It is a figure which shows an example of the (A) current waveform data (there is no pressurization force waveform data), (B) current waveform data, and the pressurization force waveform data which the resistance welding system in embodiment outputs. FIG. 4 is a diagram showing an example of (A) a nugget based on current waveform data (no pressure waveform data) and (B) a nugget based on current waveform and pressure waveform data of the resistance welding system in the embodiment. FIG. 5 is a diagram showing another example of a nugget based on (A) output current waveform data (no pressure waveform data) and (B) output current waveform data (no pressure waveform data) of the resistance welding system in the embodiment. FIG. 5 is a diagram showing another example of a nugget based on (A) output current waveform data and applied pressure waveform data and (B) current waveform data and applied pressure waveform data of the resistance welding system in the embodiment; It is a block diagram showing an example of hardware constitutions of an information processor of a resistance welding system in an embodiment.

Hereinafter, a resistance welding system, its control method, and a control program according to an embodiment of the present invention will be described in detail with reference to the drawings.

First, the function of the resistance welding system will be described with reference to FIG. Drawing 1 is a block diagram showing an example of software composition of a resistance welding system in an embodiment.

In FIG. 1 , a resistance welding system 1 includes an information processing device 10 . The resistance welding system 1 may include a resistance weld section 20 or a pressure section 30 . For example, the resistance welding system 1 may include the information processing device 10, and the resistance welding section 20 and the pressure section 30 may be separate systems. Moreover, the resistance welding system 1 may include the information processing device 10 and the resistance welding section 20, and the pressure section 30 may be a separate system. Moreover, the resistance welding system 1 may include the information processing device 10 , the resistance welding section 20 and the pressure section 30 . The information processing device 10 is communicably connected to the server 4 via the network 9 . Resistance welding system 1 may include server 4 . Although FIG. 1 illustrates a system configuration in which the resistance welding system 1 includes one information processing device 10, one resistance welding unit 20, one pressure unit 30, and one server 4, the system configuration is limited to this. not a thing For example, in the resistance welding system 1, a plurality of resistance welding units 20, a pressure unit 30, or a server 4 are connected to a single information processing device 10, and the single information processing device 10 is connected to a plurality of resistance welding units 20, It may be connected to the pressurizing unit 30 or the server 4 .

The information processing apparatus 10 includes functional units of a UI providing unit 11 , drawing data acquisition unit 12 , waveform value acquisition unit 13 , waveform generation unit 14 , output unit 15 , communication control unit 16 and storage unit 17 . The waveform generator 14 has functional units of a current waveform generator 141 and a pressure waveform generator 142 . Each functional unit of the information processing apparatus 10 according to the present embodiment will be described as a functional module realized by a control program (software) of the resistance welding system according to the present embodiment.

The UI providing unit 11 provides a user interface (UI: User Interface) for a user to input drawing data. The UI is a point of contact between the user and the information processing apparatus 10, and has, for example, an output function for displaying or reporting information to the user or an input function for receiving instructions from the user. For example, the UI has an output function for a display device or speaker, or an input function for a keyboard, mouse, or the like. The UI in the present embodiment exemplifies a case where it has a function of outputting display data to a display and a function of acquiring input data from a keyboard or mouse.

Drawing data is data for generating waveforms, and is data input by the user via the UI. The UI displays a screen for inputting drawing data and enables drawing data to be input to the displayed screen. For example, the UI displays a coordinate system in which multiple points can be plotted, and allows the user to input multiple points plotted with respect to the displayed coordinate system as drawing data. A coordinate system is a two-dimensional space composed of two-dimensional coordinate axes such as an x-axis and a y-axis. The user plots the drawing data specifying the x-axis value and the y-axis value with respect to the coordinate system of the displayed input screen. The number of plots of drawing data is one or two or more points. Also, the UI may allow drawing data to be input by, for example, inputting numerical values from a keyboard. A specific example of drawing data input via the UI will be illustrated and described later.

Drawing data in the present embodiment refers to at least one of current drawing data for generating current waveform data and pressure drawing data for generating pressure waveform data.

The drawing data acquisition unit 12 acquires drawing data input by the user via the UI provided by the UI providing unit 11 . For example, if the drawing data is information of points plotted in the coordinate system, the drawing data acquisition unit 12 acquires point data (eg, x, y data) of the coordinate axes in the coordinate system. In the coordinate system displayed on the UI, the drawing data acquisition unit 12 acquires data each time one point is plotted by the user, when a plurality of points are plotted, or when there is an explicit instruction from the user. Get drawing data when As described above, the drawing data in this embodiment is at least one of the current drawing data and the pressure drawing data, and the drawing data acquisition unit 12 acquires the current drawing data or the pressure drawing data.

The waveform value acquisition unit 13 acquires waveform values suitable for welding. Waveform values suitable for welding are, for example, appropriate current waveform values or pressure waveform values for a given workpiece. In resistance welding, the relationship between welding current (kA) and nugget diameter for a given workpiece has been conventionally understood. Also, the relationship between the applied pressure and the life of the electrode has been grasped. By acquiring waveform values suitable for welding, the waveform value acquiring unit 13 can acquire current waveform values or pressure waveform values suitable for welding, which have been conventionally understood.

For example, the waveform value acquisition unit 13 acquires current waveform values stored in the welding control unit 21 of the resistance welding unit 20 or pressure waveform values stored in the pressure control unit 31 of the pressure unit 30 . Also, the waveform value acquiring unit 13 may acquire waveform values from the server 4 .

The waveform generation unit 14 generates waveform data used in resistance welding based on the drawing data acquired by the drawing data acquisition unit 12 . The waveform generator 14 has a current waveform generator 141 and a pressure waveform generator 142 . The current waveform generation unit 141 generates current waveform data when the drawing data acquired by the drawing data acquisition unit 12 is current drawing data. The pressure waveform generation unit 142 generates pressure waveform data when the drawing data acquired by the drawing data acquisition unit 12 is pressure drawing data.

The current waveform data is data that defines the waveform of the current that is passed from the electrode 22 to the work to be welded (not shown) in resistance welding. The current waveform data is, for example, data that defines a current value that changes over time. The current waveform data may be an upslope where the current value increases over time, a downslope where the current value decreases over time, or a constant current where the current value does not change over time. Also, the current waveform data may be a sinusoidal waveform or a pulse waveform.

The pressurizing force waveform data is data that defines the pressurizing force waveform when the works are brought into pressure contact with each other via the actuator 32 during resistance welding. The pressurizing force waveform data is, for example, data that defines the pressurizing force that changes with the lapse of time. The applied force waveform data may be data in which the applied force changes stepwise with the lapse of time.

For example, when the drawing data acquired by the drawing data acquiring unit 12 is drawing data for one point, the waveform generating unit 14 generates a constant current value or pressure based on the acquired drawing data for one point. generates the waveform data shown. Further, when the drawing data acquired by the drawing data acquiring unit 12 is the drawing data of two points, the waveform generation unit 14 generates a waveform representing a line segment connecting the two points based on the acquired drawing data of the two points. data may be generated. Further, when the drawing data acquired by the drawing data acquisition unit 12 is drawing data of three or more points, the waveform generation unit 14 indicates a polygonal line connecting each point based on the acquired drawing data of three or more points. Generate waveform data or approximation curve. Approximate curves can be generated by, for example, an optimum function using the least squares method.

The waveform generator 14 also calculates the effective value of the generated waveform data. Calculation of the effective value of the current waveform data can be performed by calculating the effective value of the current value during the current supply time. That is, the effective value of the current value can be calculated by calculating the amount of current during the current supply time and taking the power amount as the average value of the current during the current supply time. Similarly, the calculation of the effective value of the pressurizing force waveform data can be performed by calculating the effective value of the pressurizing force during the pressurizing time.

The waveform generation unit 14 may calculate a conversion ratio for conversion so that the calculated effective value and the waveform value acquired by the waveform value acquisition unit 13 are equal. By multiplying the calculated effective value of the waveform data by the conversion ratio, the waveform value obtained by the waveform value obtaining unit 13 and the effective value become the same value. By making the effective value of the waveform data the same as the waveform value suitable for welding, even if the user plots multiple points from the UI with only the shape (profile) of the waveform in mind, the conversion ratio It is possible to automatically adjust the y-axis value of the waveform data. As a result, it is possible to reduce the input load of the drawing data input by the input person, and prevent generation of waveform data greatly deviating from waveform values suitable for welding. In addition, since the effective value of the waveform data is the same as the waveform value suitable for welding, the user can set the welding current or the applied pressure in the same manner as the conventional waveform value input. In the present embodiment, as will be described later, the waveform data and the conversion ratio are output from the output unit 15, but the waveform generation unit 14 outputs the waveform data to which the conversion ratio is applied (multiplied). may be generated.

The output section 15 outputs the waveform data generated by the waveform generation section 14 . For example, the output section 15 outputs the current waveform data generated by the current waveform generation section 141 to the resistance welding section 20 . The output unit 15 also outputs the pressure waveform data generated by the pressure waveform generation unit 142 to the pressure unit 30 . The output section 15 may output the pressure waveform data generated by the pressure waveform generation section 142 to the pressure section 30 via the resistance welding section 20 . Further, the output unit 15 may output the current waveform data and the pressure waveform data to the resistance welding unit 20, and the resistance welding unit 20 may output the pressure waveform data to the pressure unit 30. .

Also, the output unit 15 may output the conversion ratio calculated by the waveform generation unit 14 . For example, the output section 15 outputs the current waveform data and the conversion ratio to the resistance welding section 20 . Also, the output unit 15 may output the pressure waveform data and the conversion ratio to the pressure unit 30 . Calculation of the conversion ratio in the waveform generator 14 is performed arbitrarily. Therefore, the output unit 15 may output the waveform data generated by the waveform generation unit 14 as it is.

The communication control unit 16 controls communication with the server 4 connected via the network 9 . The network 9 is a wired or wireless communication path, and any communication means such as a communication protocol can be used. The communication control unit 16 transmits data to the server 4 or receives data from the server 4 .

The communication control unit 16 provides the waveform data generated by the waveform generation unit 14 to the server 4 . The server 4 stores the waveform data acquired from the communication control section 16 . The server 4 may provide stored waveform data. For example, it may be difficult to obtain optimal values for welding conditions including current waveform data or pressure waveform data depending on the workpiece. If the waveform data generated by the information processing device 10 contains the optimum welding conditions for a given workpiece, the waveform data acquired from the information processing device 10 may contain know-how and have value in itself. For example, know-how can be shared by sharing the waveform data stored in the server 4 with other resistance welding systems. For example, by sharing waveform data within the same company via the server 4, it is possible to reduce the cost of examining welding conditions. The server 4 may perform login authentication and provide waveform data to another authenticated information processing apparatus. Also, the server 4 may charge for providing the waveform data. Server 4 may also be able to provide waveform data for a particular resistance welding system. For example, by allowing a person who has placed an order to weld a workpiece to provide waveform data with a limited period of use, etc. to the resistance welding system of the ordering party, it is possible to prevent leakage of welding know-how to the ordering party. Welding at the supplier can be made possible.

Further, the communication control unit 16 may acquire waveform data stored in the server 4 from the server 4 . The waveform data acquired from the server 4 is output via the output unit 15 and used for resistance welding. The UI providing unit 11 may edit the waveform data acquired from the server 4 via the UI and input drawing data. For example, the user may want to modify part of the waveform data acquired from the server 4 via the communication control unit 16 according to welding conditions. The UI providing unit 11 makes it possible to generate waveform data more easily than generating new waveform data by enabling editing of the waveform data acquired via the UI.

The storage unit 17 stores data. For example, the storage unit 17 stores drawing data acquired by the drawing data acquisition unit 12, waveform values acquired by the waveform value acquisition unit 13, waveform data generated by the waveform generation unit 14, or waveform data acquired from the server 4. Store waveform data. The stored data may be read from each functional unit described above.

Resistance welding section 20 has welding control section 21 and electrode 22 . Welding control unit 21 controls the welding current applied to electrode 22 . Based on the current waveform data acquired from the output unit 15, the welding control unit 21 calculates the current value and the energization time of the welding current to be applied to the electrode 22, and energizes at a predetermined timing. For example, the welding control unit 21 acquires from the pressure unit 30 a signal indicating that the pressure of the workpiece by the pressure unit 30 has been completed, and starts supplying the welding current. Also, the welding control unit 21 may output a signal to the pressurizing unit 30 indicating that the application of the welding current has ended.

The pressure unit 30 has a pressure control unit 31 and an actuator 32 . The pressure controller 31 controls driving of the actuator 32 . The pressure unit 30 may be included in the resistance welding system 1 or may be an external device not included in the resistance welding system 1 . For example, the pressure unit 30 may be a robot system, and the pressure control unit 31 may be a robot control device.

The pressurization control unit 31 calculates the driving amount or the driving force of the actuator 32 based on the pressurizing force waveform data acquired from the output unit 15, and drives the actuator 32 at a predetermined timing. For example, the pressurization control unit 31 detects that the work is set at the welding position, starts pressurization, and outputs a signal indicating that the pressurization is completed to the welding control unit 21 . The pressurization control section 31 may acquire a signal indicating that the application of the welding current has ended from the welding control section 21 and terminate the pressurization.

The actuator 32 moves the electrode 22 to pressurize the workpiece. Actuator 32 may be implemented, for example, by a servomotor and ball spline combination. The servomotor rotates the ball screw based on the control signal output from the pressure control unit 31 to move the electrode 22 attached to the ball spline.

It should be noted that the above-described functional units of the resistance welding system 1 are examples of the functional units of the resistance welding system 1, and the functions of the resistance welding system 1 are not limited. For example, the resistance welding system 1 does not need to have all the functional units described above, and may have some functional units. Also, the resistance welding system 1 may have functions other than those described above. For example, the resistance welding system 1 may have an input function for inputting information, and an output function for informing the operating state of the device using an LED lamp or the like.

Moreover, as described above, each of the functional units of the resistance welding system 1 has been described as being realized by software (excluding the electrode 22 and the actuator 32). However, at least one or more of the functional units included in the resistance welding system 1 may be realized by hardware.

Moreover, one of the functional units included in the resistance welding system 1 may be implemented by dividing one functional unit into a plurality of functional units. Also, any two or more of the functional units of the resistance welding system 1 may be integrated into one functional unit. That is, FIG. 1 expresses the functions of the resistance welding system 1 by functional blocks, and does not indicate that each functional unit is configured by a separate program file or the like, for example.

Moreover, the resistance welding system 1 may be a device realized by one housing or a system realized by a plurality of devices connected via a network or the like. For example, the resistance welding system 1 may implement some or all of its functions by other virtual devices such as cloud services provided by a cloud computing system. That is, the resistance welding system 1 may implement at least one or more of the above functional units in another device. Moreover, the resistance welding system 1 may be a general-purpose computer such as a desktop PC, or may be a dedicated device with limited functions.

Next, an overview of the resistance welding system 1 will be described with reference to FIG. Drawing 2 is a figure showing an example of an outline of resistance welding system 1 in an embodiment.

In FIG. 2 , the resistance welding system 1 has an information processing device 10 . The information processing device 10 outputs current waveform data and pressure waveform data to the welding control unit 21 . The welding control unit 21 transmits the pressure waveform data acquired from the information processing device 10 to the pressure control unit 31 . The welding control unit 21 and the pressurization control unit 31 may have a communication path for communicating signals such as completion of pressurization of the workpiece 5 as described above. The illustrated resistance welding system 1 sends current waveform data and applied force waveform data to the welding control unit 21. Therefore, if the information processing device 10 and the welding control unit 21 are communicatively connected, the information processing device 10 and The connection with the pressurization control section 31 can be dispensed with. This makes it possible to simplify the output of waveform data from the information processing apparatus 10 . The information processing device 10 may directly output the pressure waveform data to the pressure control unit 31 (illustrated by a dashed line).

Resistance welding in the resistance welding system 1 is performed by applying pressure to the workpiece 5 by the electrode 22 and applying welding current from the electrode 22 . First, the pressurization control unit 31 sends a control signal to the actuator 32 to move the electrode 22 in the vertical direction so that the work 5 is sandwiched between the electrodes 22 and pressurized. When the pressurization to the work 5 is completed, the welding control unit 21 starts applying the welding current to the electrode 22 to form the nugget 51 on the work 5 and terminates the application. After the energization is finished, the pressurization control unit 31 moves the electrode 22 to finish pressurizing the workpiece 5 .

Welding controller 21 applies a welding current to electrode 22 based on the current waveform data. The welding control unit 21 calculates the temporal transition of the current value from the start of the current application to the end of the current application based on the current waveform data, for example, and controls the welding current applied to the electrode 22 based on the calculated current value. The welding control unit 21 forms a nugget 51 by applying a controlled welding current from the electrode 22 to the workpiece 5 .

The nugget 51 is a melted metal portion of the workpiece formed at the portion pressed by the electrode 22 . The welding strength in resistance welding is determined by the tensile shear strength, the nugget diameter, etc., but the reference diameter of the appropriate nugget diameter is the plate thickness t if the plate thickness of the workpieces to be welded is the same plate thickness t, and the different plate In the case of thickness, the plate thickness t on the thin plate side is used, and if the reference nugget diameter satisfies 4√t or more, it is considered acceptable. In some cases, if the ISO standard nugget diameter is 5√t or more, it is accepted.

The pressure controller 31 outputs a control signal to the actuator 32 based on the pressure waveform data. The pressurization control unit 31 calculates, for example, the temporal transition of the pressurization force from the start of pressurization to the end of pressurization based on the pressurization force waveform data, and outputs a control signal based on the calculated pressurization force. The actuator 32 controls the pressing force that presses the workpiece 5 based on the control signal.

Although FIG. 2 shows a case where the current value and the applied force are controlled based on the waveform data, for example, the applied force is not controlled based on the waveform data, and only the current value is controlled based on the current waveform data. You may do so. Also, the current value may not be controlled based on the waveform data, and only the pressure may be controlled based on the pressure waveform data.

Next, operation of the resistance welding system 1 will be described with reference to FIG. FIG. 3 is a flow chart showing an example of the operation of the resistance welding system in the embodiment. In addition, although the operation|movement demonstrated here demonstrates the case where it is performed mainly by the resistance welding system 1, it may be implement|achieved in each function which the resistance welding system 1 demonstrated in FIG. 1 has.

In FIG. 3, the resistance welding system 1 starts UI (step S11). Activation of the UI can be executed, for example, by activating the UI program in a PC in which a control program for the resistance welding system is installed. The UI, for example, allows the user to input plotting data in the displayed coordinate system.

After executing the process of step S11, the resistance welding system 1 determines whether or not the current drawing data has been acquired (step S12). Whether or not the current drawing data has been acquired can be determined, for example, by whether or not the user has input the current drawing data via the UI.

When determining that the current drawing data has been acquired (step S12: YES), the resistance welding system 1 generates current waveform data and displays the generated current waveform data on the UI (step S13). By displaying the generated current waveform data on the UI, the user can immediately confirm the current waveform data generated for the input current drawing data.

On the other hand, when determining that the current drawing data has not been acquired (step S12: NO), the resistance welding system 1 determines whether or not the applied force drawing data has been acquired (step S14). Whether or not the pressure drawing data has been acquired can be determined by, for example, whether or not the user has input the pressure drawing data via the UI.

When it is determined that the applied force drawing data has been acquired (step S14: YES), the resistance welding system 1 generates applied force waveform data and displays the generated applied force waveform data on the UI (step S15). By displaying the generated pressure waveform data on the UI, the user can immediately check the pressure waveform data generated for the input pressure drawing data.

When it is determined that the pressure drawing data has not been acquired (step S14: NO), the resistance welding system 1 repeats the processes of steps S12 and S14 and waits for acquisition of current drawing data or pressure drawing data.

After executing the process of step S13 or after executing the process of step S15, the resistance welding system 1 determines whether or not to end the editing (step S16). Whether or not to end editing can be determined, for example, by whether or not the user has performed an explicit operation to end editing.

When it is determined not to end editing (step S16: NO), the resistance welding system 1 returns to the process of step S12 and waits for acquisition of current drawing data or pressure drawing data. Thereby, the resistance welding system 1 enables correction of drawing data once input. The resistance welding system 1 generates and displays waveform data each time drawing data is corrected in the processing of steps S12 to S16.

When it is determined to end the editing (step S16: YES), the resistance welding system 1 outputs the last generated waveform data (step S17), and ends the operation shown in the flowchart. In the process of step S17, the resistance welding system 1 outputs the waveform data generated in the process of step S13 or the process of step S15. The current waveform data is output to welding control section 21 , and the pressure waveform data is output to pressure control section 31 . For example, when the current waveform data is generated in the process of step S13 and the applied force waveform data is not generated, the resistance welding system 1 outputs only the current waveform data. Further, when the applied force waveform data is generated in the processing of step S15 and the current waveform data is not generated, the resistance welding system 1 may output only the applied force waveform data.

Although FIG. 3 illustrates the case of outputting the last generated waveform data, for example, a plurality of generated waveform data may be output. For example, in resistance welding, when welding a plurality of locations on a workpiece, the resistance welding system 1 may output different waveform data for each welding location.

Next, generation of current waveform data using the UI will be described with reference to FIGS. 4 to 6. FIG. 4 to 6 show display screens displayed by the UI. The user generates waveform data while checking the display screen. 4 to 6 exemplify the case of generating the current waveform data, the same display screen is used to generate the pressure waveform data as well.

FIG. 4 is a diagram showing an example of current drawing data input on the UI provided by the resistance welding system in the embodiment. FIG. 5 is a diagram showing an example of current waveform data display on the UI provided by the resistance welding system in the embodiment. FIG. 6 is a diagram showing an example of (A) current waveform data and (B) conversion ratio output by the resistance welding system in the embodiment.

FIG. 4 shows an example of an xy coordinate system in which the x-axis is the current application time (cycle: cyc) and the y-axis is the welding current (kA). The user can plot the current drawing data against the xy coordinate system displayed by the UI. For example, the user can plot the current drawing data by operating the mouse to move the cursor to the desired plotting position and clicking. The figure shows the result of plotting current values at 8 points from 0 cyc to 17.5 cyc as current drawing data. The number of current drawing data that the user can plot is arbitrary. For example, if you want to generate current waveform data with a complicated waveform, you can increase the number of plots, and you can also generate current waveform data with a simple waveform (e.g., linear waveform). You can reduce the number of plots if you want them to be generated. Also, the number of plots may be increased in portions where the current value is desired to be specified in detail.

The user completes the plotting of the current drawing data and ends the input of the current drawing data. Completion of plotting may be executed, for example, by pressing a completion button (not shown).

FIG. 5 is a display example in which current waveform data generated based on the current drawing data input in FIG. 4 is displayed by UI. The illustrated current waveform data is generated as a polygonal line in which the current drawing data are connected by line segments. Also, the current waveform data may be generated as a smoothed approximation curve based on the current drawing data.

Here, the user can modify the plotted current drawing data. For example, the p point can be moved by dragging the p point with the energization time of 4 cyc with the mouse. By moving and correcting the p-point, the current waveform data is regenerated and displayed.

FIG. 6A shows current waveform data output to the welding control section 21. FIG. FIG. 6B shows conversion ratios output to the welding control unit 21. As shown in FIG. As described above, the conversion ratio is a coefficient for converting the effective value of the current waveform data to the waveform value suitable for welding acquired by the waveform value acquisition unit 13 . The y-axis indicates the conversion ratio (magnification) to the effective value of the current waveform data.

As illustrated in FIGS. 4 to 6, the UI allows the user to freely set the current waveform data or pressure waveform data used in resistance welding as if drawing a diagram with a CAD (Computer Aided Design) program. and This enables current waveform control or pressurizing force waveform control that smoothly changes the waveform. In resistance welding, the temperature of the work and the formation of nuggets are closely related, so detailed temperature control is effective in order to form good nuggets.

For example, depending on the material of the work, it may be possible to form a good nugget by rapidly increasing the temperature of the work exponentially. By generating exponentially increasing current waveform data in the UI, the welding control unit 21 can control the welding current so that the temperature of the work increases exponentially. This makes it possible to form a nugget suitable for the material of the work.

Also, depending on the material of the work, it may be possible to form a good nugget by increasing the temperature of the work smoothly logarithmically. Even in this case, by generating current waveform data that increases logarithmically in the UI, it is possible to logarithmically increase the workpiece temperature information and form a nugget suitable for the workpiece material.

Next, results of resistance welding using current waveform data will be described with reference to FIGS. 7 to 10. FIG. FIG. 7 is a diagram showing another example of current waveform data output by the resistance welding system in the embodiment. FIG. 8 is a diagram showing an example of the characteristics of the welding current and nugget diameter of the resistance welding system in the embodiment. FIG. 9 is a diagram showing another example of the characteristics of the welding current and nugget diameter of the resistance welding system in the embodiment. FIG. 10 is a diagram showing an example of the weld lobe of the resistance welding system in the embodiment.

In FIG. 7, the solid line indicates current waveform data at 20 cyc generated in the UI. A dashed line indicates a constant current (8 kA) at 20 cyc. The current waveform data has a smoother rising speed (slope of the graph) at the start of energization compared to the constant current, but the peak current value is larger (11.3 kA). In addition, the current waveform data shows that the current value is gradually decreased from 3 cyc to about 6.8 kA, and then the current value is gradually increased until the end of welding.

FIG. 8 shows JAC270D (0.6 mm ) side nugget diameter (mm). The solid line indicates the case of energization with the current waveform data described in FIG. 7, and the dashed line indicates the case of energization with the constant current described with reference to FIG. In FIG. 8, with a constant current, expulsion occurred at a welding current of about 8.4 kA, and the nugget diameter did not reach about 6.1 mm or more. On the other hand, when the welding current was controlled based on the current waveform data, the nugget diameter increased to approximately 6.8 mm. Also, the welding current at which expulsion occurs increased to about 8.7 kA. That is, it was confirmed that under the welding conditions shown in FIG. 8, a larger nugget diameter can be formed by controlling the welding current based on the current waveform data as compared to the constant current. It was also confirmed that the welding current at which expulsion occurs can be increased. 4√t is 3.10 mm, which satisfies the standard value under any conditions.

FIG. 9 shows JSC980Y (1.6 mm) when energized under the welding conditions of JAC270D (0.6 mm), JSC980Y (1.4 mm), and JSC980Y (1.6 mm) with the applied pressure fixed at 4500 N. ) side nugget diameter (mm). The solid line indicates the case where the current waveform data explained in FIG. 7 is applied, and the dashed line shows the case where the constant current explained in FIG. 7 is applied. In FIG. 9, with a constant current, expulsion occurred at a welding current of about 7.6 kA, and the nugget diameter did not reach about 7.6 mm or more. On the other hand, when the welding current was controlled based on the current waveform data, the nugget diameter increased to approximately 8.0 mm. Also, the welding current at which expulsion occurs increased to about 9.2 kA. That is, it was confirmed that even under the welding conditions shown in FIG. 9, a larger nugget diameter can be formed than when the constant current is used by controlling the welding current based on the current waveform data. It was also confirmed that the welding current at which expulsion occurs can be increased. 4√t is 5.06 mm, which satisfies the reference value under any conditions.

In FIG. 10, the left figure shows the weld lobe at a constant current, and the right figure shows the weld lobe when the welding current is controlled based on the current waveform data. Weld lobe indicates the appropriate range of current welding conditions from the current that produces a nugget diameter of 4√t or more to the occurrence of expulsion. A wider weld lobe indicates a wider range of welding conditions. Weld lobes at constant current ranged from 7.2 to 7.6 kA. On the other hand, the weld lobe when controlling the welding current based on the current waveform data was in the range of 7.2 to 8.6 kA. That is, it is possible to widen the range of welding conditions by controlling the welding current based on the current waveform data. That is, in the present embodiment, by controlling the welding current based on the current waveform data in the above workpiece (three-layered thick plate and thin plate), the setting of the optimum welding conditions is likely to be simplified. I was able to confirm that.

Next, results of resistance welding using current waveform data and applied force waveform data will be described with reference to FIGS. 11 and 12. FIG. FIG. 11 is a diagram showing an example of (A) current waveform data (without pressure waveform data) and (B) current waveform data and pressure waveform data output by the resistance welding system in the embodiment. FIG. 12 is a diagram showing an example of (A) a nugget based on current waveform data (no pressure waveform data) and (B) a nugget based on current waveform and pressure waveform data of the resistance welding system in the embodiment.

In FIG. 11A, the applied pressure is a constant value of 3600N. In FIG. 11B, the applied force varies from 3600N to 2100N when the welding current is stopped, based on the applied force waveform data. The workpieces to be welded are JAC270D (0.5 mm), JAC980DU (1.6 mm), and JAC980DU (1.6 mm).

In FIGS. 11A and 11B, the welding current is applied twice. The maximum value is about 7000 kA for the first energization and about 8500 kA for the second energization.

FIG. 12(A) shows the shape of the nugget under the welding conditions of FIG. 11(A). Here, the nugget diameter of JAC270D (0.5 mm) on the thin plate side was 1.7 mm, which was less than the nugget diameter standard of 4√t (2.83 mm). The nugget diameter of JAC980DU (1.6 mm) on the thick plate side was 6.5 mm, which was equal to or larger than the nugget diameter standard of 4√t (5.06 mm). That is, when the pressing force was set to a constant value of 3600 N, the nugget diameter on the thick plate side satisfied the standard value, but the nugget diameter on the thin plate side could not satisfy the standard value.

FIG. 12(B) shows the shape of the nugget under the welding conditions of FIG. 11(B). Here, the nugget diameter of JAC270D (0.5 mm) on the thin plate side was 4.0 mm, which was equal to or larger than the nugget diameter standard of 4√t (2.83 mm). The nugget diameter of JAC980DU (1.6 mm) on the thick plate side was 6.5 mm, which was equal to or larger than the nugget diameter standard of 4√t (5.06 mm). That is, when the applied force was controlled by the applied force waveform data, both the thick plate side and the thin plate side could satisfy the reference value of the nugget diameter. That is, in the present embodiment, it can be confirmed that the optimum welding conditions can be set by controlling the applied pressure based on the applied pressure waveform data in the above work (three sheets of thick plate and thin plate). rice field.

Next, another implementation result of resistance welding using current waveform data and applied force waveform data will be described with reference to FIGS. 13 and 14. FIG. FIG. 13 shows another example of a nugget based on (A) output current waveform data (no pressure waveform data) and (B) current waveform data (no pressure waveform data) of the resistance welding system according to the embodiment. It is a diagram. FIG. 14 is a diagram showing another example of a nugget based on (A) output current waveform data and pressure waveform data and (B) current waveform data and pressure waveform data of the resistance welding system according to the embodiment. The work to be welded in this embodiment is made of A6022, which is a 6000 series aluminum alloy, and has a thickness of 1.6 mm.

In FIG. 13A, the applied pressure is a constant value of 5600N. The welding current is a constant value of 35 kA, and the welding time is 133 msec. In FIG. 13B, the formed nugget diameter was 7.2 mm. The photograph is a cross-sectional view of the nugget.

In FIG. 14A, the pressure is 4600N in the first approximately 65 msec, and is controlled by the pressure waveform data from 70 msec to 6600N. The welding current is a constant value of 35 kA, and the welding time is 133 msec. In FIG. 14B, the formed nugget diameter was 7.6 mm. In this embodiment, the nugget diameter could be increased by controlling the pressure based on the pressure waveform data. That is, in this embodiment, it was confirmed that the optimum welding conditions can be set by controlling the applied pressure using the applied pressure waveform data even when the work is an aluminum alloy.

Next, the hardware configuration of the information processing device 10 will be described with reference to FIG. 15 . FIG. 15 is a block diagram showing an example of the hardware configuration of the information processing device 10 according to the embodiment.

The information processing apparatus 10 has a CPU (Central Processing Unit) 101 , a RAM (Random Access Memory) 102 , a ROM (Read Only Memory) 103 , an I/O device 104 and a communication I/F (Interface) 105 . The information processing device 10 is a device that executes a control program for the resistance welding system 1 described with reference to FIG.

The CPU 101 controls the user terminal by executing an information processing program stored in the RAM 102 or ROM 103 . The information processing program is acquired, for example, from a recording medium recording the program or from a program distribution server via a network, installed in ROM 103, read out by CPU 101, and executed.

The I/O device 104 has an operation input function and a display function (operation display function). The I/O device 104 is, for example, a touch panel. The touch panel enables the user of the information processing device 10 to perform operation input using a fingertip, a touch pen, or the like. The I/O device 104 in this embodiment uses a touch panel having an operation display function. may have. In that case, the display screen of the touch panel can be implemented as the display screen of the display device, and the operation of the touch panel can be implemented as the operation of the operation input device. Note that the I/O device 104 may be implemented in various forms such as a head-mounted type, glasses type, wristwatch type display, and the like.

Communication I/F 105 is an I/F for communication. The communication I/F 105 executes short-range wireless communication such as wireless LAN, wired LAN, and infrared. Although the drawing shows only the communication I/F 105 as a communication I/F, the information processing apparatus 10 may have respective communication I/Fs in a plurality of communication methods.

It should be noted that a program for realizing the functions constituting the apparatus described in this embodiment may be recorded in a computer-readable recording medium, and the program recorded in the recording medium may be read into a computer system and executed. , the above-described various processes of the present embodiment may be performed. Note that the “computer system” referred to here may include hardware such as an OS and peripheral devices. The "computer system" also includes the home page providing environment (or display environment) if the WWW system is used. In addition, "computer-readable recording medium" means writable non-volatile memory such as flexible disk, magneto-optical disk, ROM, flash memory, etc., portable medium such as CD-ROM, hard disk built in computer system, etc. storage device.

Furthermore, "computer-readable recording medium" means a volatile memory (e.g., DRAM (Dynamic Random Access Memory)), which holds a program for a certain period of time. Further, the above program may be transmitted from a computer system storing this program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in a transmission medium. Here, the "transmission medium" for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line. Further, the program may be for realizing part of the functions described above. Furthermore, a so-called difference file (difference program), which realizes the functions described above in combination with a program already recorded in the computer system, may be used.

Although the embodiments of the present invention have been described above with reference to the drawings, the specific configuration is not limited to these embodiments, and various modifications are possible without departing from the scope of the present invention. be

1 resistance welding system 10 information processing device 11 UI providing unit 12 drawing data acquisition unit 13 waveform value acquisition unit 14 waveform generation unit 141 current waveform generation unit 142 pressure waveform generation unit 15 output unit 16 communication control unit 17 storage unit 20 resistance welding Part 21 Welding control part 22 Electrode 30 Pressure part 31 Pressure control part 32 Actuator 4 Server 5 Work 51 Nugget 9 Network 101 CPU
102 RAMs
103 ROMs
104 I/O device 105 Communication I/F

Claims (11)

a UI providing unit that provides a user interface (UI) for a user to input drawing data;
a drawing data acquisition unit that acquires drawing data input by a user via the UI provided by the UI providing unit;
a waveform value acquisition unit that acquires a waveform value that is a numerical value including a current value or a pressure value suitable for welding;
a waveform generation unit that generates waveform data used in resistance welding based on the drawing data acquired by the drawing data acquisition unit;
an output unit that outputs the waveform data generated in the waveform generation unit,
The waveform generation unit calculates an effective value of the generated waveform data, and further sets a conversion ratio for conversion so that the calculated effective value and the waveform value obtained by the waveform value obtaining unit are equal. calculate,
The resistance welding system , wherein the output unit outputs the conversion ratio calculated by the waveform generation unit . The waveform generator generates, as the waveform data, current waveform data of a current applied to a workpiece in resistance welding based on the drawing data,
2. The resistance welding system according to claim 1, wherein said output section outputs said current waveform data generated in said waveform generation section to a resistance welding section that performs resistance welding. The waveform generator generates, as the waveform data, pressurizing force waveform data of the pressurizing force applied to the workpiece in resistance welding based on the drawing data,
The resistance welding system according to claim 1 or 2, wherein said output unit outputs said pressurizing force waveform data generated in said waveform generation unit to a pressurizing unit that presses a workpiece. 2. The UI providing unit provides the UI for displaying the waveform data generated by the waveform generating unit according to the input of the drawing data when a user inputs the drawing data. 4. The resistance welding system according to any one of 3. The resistance welding system according to any one of claims 1 to 4 , further comprising a communication control unit that controls communication with a server connected via a network. The resistance welding system according to claim 5 , wherein said communication control section provides said waveform data generated in said waveform generation section to said server. The communication control unit acquires waveform data stored in the server from the server,
The resistance welding system according to claim 5 or 6 , wherein said UI providing unit edits the waveform data acquired from said server and provides a UI for inputting said drawing data. The UI providing unit displays a coordinate system capable of plotting a plurality of points, and provides a UI for a user to input a plurality of points plotted on the displayed coordinate system as the drawing data,
The resistance welding system according to any one of claims 1 to 7 , wherein the waveform generation section generates the waveform data obtained by smoothing the plurality of points as the drawing data acquired by the drawing data acquisition section. . The UI providing unit displays at least one of the plurality of points movably within the coordinate system,
9. The resistance welding system of claim 8, wherein the waveform generator regenerates waveform data based on points moved by the user. A method of controlling a resistance welding system, comprising:
a UI providing step of providing a user interface (UI) for a user to input drawing data;
a drawing data obtaining step of obtaining drawing data input by a user via the UI provided in the UI providing step;
a waveform value acquisition step of acquiring a waveform value, which is a numerical value including a current value or an applied pressure value suitable for welding;
a waveform generation step of generating waveform data used in resistance welding based on the drawing data acquired in the drawing data acquisition step;
an output step of outputting the waveform data generated in the waveform generation step;
calculating the effective value of the generated waveform data in the waveform generating step, and calculating a conversion ratio for converting such that the calculated effective value and the waveform value obtained in the waveform value obtaining step are equal to each other; calculate,
A method of controlling a resistance welding system , wherein, in the output step, the conversion ratio calculated in the waveform generation step is output . to the computer,
a UI providing function for providing a user interface (UI) for the user to input drawing data;
a drawing data acquisition function for acquiring drawing data input by a user via the UI provided by the UI providing function;
A waveform value acquisition function for acquiring waveform values, which are numerical values including current values or pressure values suitable for welding;
a waveform generation function for generating waveform data used in resistance welding based on the drawing data acquired by the drawing data acquisition function;
realizing an output function for outputting the waveform data generated by the waveform generation function,
In the waveform generation function, the effective value of the generated waveform data is calculated, and further, a conversion ratio for conversion so that the calculated effective value and the waveform value obtained in the waveform value obtaining function are equal calculate,
In the output function, outputting the conversion ratio calculated in the waveform generation function
Control program for the resistance welding system to realize the function .

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