Patent ID: 12235630

DETAILED DESCRIPTION

(Introduction to Present Disclosure)

According to JP-A-2017-102548, a production management device can manage traceability data for each workpiece. However, in the configuration of JP-A-2017-102548, different identifiers are newly assigned each time the same workpiece is located in a plurality of different production machines. In other words, each time one workpiece is sequentially located on another production machine in a production line, the one workpiece has a plurality of different identifiers. Therefore, for example, when a plurality of workpieces are joined and another workpiece is produced as in a welding process, if a new identifier is assigned to the produced workpiece in accordance with JP-A-2017-102548, a relationship between an identifier of the workpiece used in the welding process and an identifier of the produced workpiece may be complicated, and thus it may be difficult to use traceability related to the produced workpiece. That is, management of the identifier of the workpiece is complicated, and work efficiency of a system administrator is deteriorated.

Therefore, in the following embodiments, examples of an identifier management method and a reading device which support more efficient management of the identifier of the workpiece produced in a process such as welding will be described.

Hereinafter, embodiments specifically disclosing an identifier management method and a reading device according to the present disclosure will be described in detail with reference to the drawings as appropriate. However, an unnecessarily detailed description may be omitted. For example, a detailed description of a well-known matter or a repeated description of substantially the same configuration may be omitted. This is to avoid unnecessary redundancy in the following description and to facilitate understanding of those skilled in the art. It should be noted that the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the range of the claims.

First Embodiment

The welding system according to the first embodiment acquires information on identifiers of a plurality of original workpieces, and selects an identifier to be adopted as an identifier of a produced welded workpiece according to a predetermined rule based on completion of execution of a welding process using the plurality of original workpieces. The welding system sets the selected identifier as the identifier of the welded workpiece produced in the welding process. Hereinafter, the workpiece used in the welding process is defined as an “original workpiece”, and the workpiece produced in the welding process is defined as a “welded workpiece”. The “welded workpiece” may be referred to as a “secondary workpiece” or an “n-th workpiece” (n: an integer of 2 or more).

(Configuration of Welding System)

FIG.1is a schematic diagram showing a system configuration example of a welding system100. The welding system100includes a host device1connected to each of an external storage ST, an input interface UI1, and a monitor MN1, a plurality of robot control devices (for example, robot control devices2aand2b), a plurality of main welding robots (for example, main welding robots MC1aand MC1b), and a reading device3. The robot control device2ais provided corresponding to the main welding robot MC1a, the robot control device2bis provided corresponding to the main welding robot MC1b, and the same number of robot control devices are similarly provided corresponding to one main welding robot.

The host device1integrally controls the execution of the main welding (so-called welding process) executed by the corresponding main welding robots MC1a, MC1b, and so on via each of the plurality of robot control devices2a,2b, and so on. For example, the host device1reads, from the external storage ST, welding-related information input or set in advance by the user business operator (for example, a welding operator or a system administrator. The same applies hereinafter.), generates a welding process execution command including a part of contents of the welding-related information based on the welding-related information, and transmits the generated execution command to the corresponding robot control device (for example, the robot control device2a). The execution command of the main welding described above is not limited to being generated by the host device1, and may be generated by, for example, an operation panel (for example, a programmable logic controller (PLC)) of equipment in a factory or the like in which the main welding is performed, or an operation panel (for example, a teach Pendant (TP)) of the robot control devices2a,2b, and so on. The teach pendant (TP) is a device for operating the main welding robots MC1a, MC1b, and so on connected to the robot control devices2a,2b, and so on.

Here, the welding-related information is information indicating the content of the welding process executed for each main welding robot, and is created in advance for each welding process and registered in the external storage ST. The welding-related information includes, for example, the number of original workpieces required for the welding process, an identifier (hereinafter, abbreviated as “ID”) of the original workpiece used in the welding process, workpiece information including a name and welding of the original workpiece, an execution scheduled date on which the welding process is scheduled to be executed, the number of welded workpieces, and various welding conditions at the time of the welding process. The welding-related information is not limited to data of items described above. The robot control device (for example, the robot control device2a) causes the main welding robot (for example, the main welding robot MC1a) to perform the welding process using the plurality of original workpieces designated by the execution command based on the execution command transmitted from the host device1. In the present specification, the type of the welding process is not limited, but in order to make the description easy to understand, a process of joining each of the plurality of original workpieces will be described as an example (seeFIGS.3and5).

The host device1is connected to the monitor MN1, the input interface UI1, the reading device3, and the external storage ST so as to be able to input and output data, and is further connected to each of the plurality of robot control devices2a,2b, and so on so as to be able to communicate data. The host device1may include a terminal device P1integrally including the monitor MN1and the input interface UI1, and may further integrally include the external storage ST. In this case, the terminal device P1is a personal computer (PC) used by a user business operator prior to execution of a welding process (for example, main welding). The terminal device P1is not limited to the PC described above, and may be a computer device having a communication function, such as a smartphone or a tablet terminal.

The host device1acquires the above-described welding-related information from the external storage ST, generates the welding process execution command using the plurality of original workpieces based on the welding-related information, and transmits the execution command to the corresponding robot control devices2a,2b, and so on. When the host device1is notified of the completion of the welding process of each of the plurality of the original workpieces from the corresponding robot control devices2a,2b, and so on after the completion of the welding process by each of the main welding robots MC1a, MC1b, and so on, the host device1sets the ID of a welded workpiece (for example, a secondary workpiece) produced by the welding process to an ID selected in advance according to a predetermined rule. Further, the host device1generates the welding process logical data (seeFIGS.3and5) corresponding to the set welded workpiece.

The host device1stores, in the external storage ST, the information on the identification sign that can be assigned to each original workpiece and that can read the information on the ID set in the original workpiece and the ID set in the original workpiece in association with each other. Further, when the ID is set for the welded workpiece, the host device1stores the ID of the welded workpiece and the welding process logical data in the external storage ST in association with the information on the identification signs of the plurality of original workpieces. At this time, the host device1does not overwrite and store the set IDs of the welded workpieces to the IDs of the plurality of original workpieces used for producing the welded workpieces, and stores the IDs as the IDs to be output to the reading device3. The information (data) stored in association with the identification sign is not limited to the information on the ID set for the plurality of original workpieces or welded workpieces and the welding process logical data, and may include, for example, welding-related information stored in association with the ID, and a management ID (seeFIG.6). Accordingly, the host device1can appropriately manage the IDs of the welded workpieces produced by the welding process by various main welding robots, and can similarly manage the IDs of the plurality of original workpieces used for producing the welded workpieces. Details of an operation of the host device1will be described later with reference to the drawings. The host device1may display the welding process logical data including the ID of the welded workpiece on the monitor MN1.

The host device1receives information on the identification sign read by the reading device3from the reading device3capable of reading the identification sign arranged for each of the workpiece. Based on the received information on the identification sign, the host device1acquires information on the ID set for the plurality of original workpieces or the welded workpiece read by the reading device3from the external storage ST, and transmits the information to the reading device3. Here, the information acquired by the host device1is not limited to the information on the IDs set for the plurality of original workpieces or welded workpieces, and may include, for example, welding-related information, welding process logical data, and management IDs (seeFIG.6) stored in association with the IDs.

Here, the identification sign is an identification sign on which the ID set for the original workpiece or the welded workpiece is readable, and is, for example, a two-dimensional barcode, a QR code (registered trademark), a barcode, an IC tag, or an RF tag. The identification sign may be directly assigned (that is, marked) to the original workpiece by a laser, or may be assigned by attaching the IC tag or the RF tag.

The monitor MN1may be configured with a display device such as a liquid crystal display (LED) or an organic electroluminescence (EL). The monitor MN1may display, for example, a screen indicating the welding process logical data including the ID of the welded workpiece, which is output from the host device1. Instead of the monitor MN1or together with the monitor MN1, a speaker (not shown) may be connected to the host device1, and the host device1may output the ID included in the welding process logical data by voice via the speaker.

The input interface UI1is a user interface that detects an input operation of the user business operator and outputs the input operation to the host device1, and may be configured using, for example, a mouse, a keyboard, or a touch panel. The input interface UI1receives, for example, an input operation when the user business operator creates the welding-related information, or an input operation when a welding process execution command is transmitted to the robot control device2a.

The reading device3is a device that reads the identification sign arranged on each workpiece and outputs information on the ID set for the original workpiece or the welded workpiece, and may include, for example, a camera, a charge coupled device (CCD) sensor, or a laser. The reading device3may be a terminal device capable of reading the identification sign by the operation of the user business operator, or may be a device that is provided in a robot that executes the welding process or a robot that executes an inspection of the welding portion and is capable of reading the identification sign based on a control command of the host device1before and after the welding process or the inspection process. The reading device3transmits the information on the read identification sign to the host device1. The reading device3displays (outputs) the ID of the original workpiece or the welded workpiece received from the host device1. The reading device3may output the ID of the original workpiece or the welded workpiece by voice.

The external storage ST is configured using, for example, a hard disk drive (HDD) or a solid state drive (SSD). The external storage ST stores, for example, information on the identification sign arranged on each workpiece, data of welding-related information created for each welding process, and welding process logical data (seeFIGS.3and5) including the ID of the welded workpiece produced by the welding process.

The robot control devices2a,2b, and so on are connected so as to be able to communicate data with the host device1, and are connected so as to be able to communicate data with each of the main welding robots MC1a, MC1b, and so on. When the robot control devices2a,2b, and so on receive the welding process execution command sent from the host device1, the robot control devices2a,2b, and so on control the corresponding main welding robots MC1a, MC1b, and so on based on the execution command to execute the welding process. When detecting the completion of the welding process, the robot control devices2a,2b, and so on generate a welding completion notification indicating the completion of the welding process and transmit the welding completion notification to the host device1. Accordingly, the host device1can appropriately detect the completion of the welding process based on each of the robot control devices2a,2b, and so on. The method of detecting the completion of the welding process by the robot control devices2a,2b, and so on may be a method of determining the completion of the welding process based on a signal indicating the completion of the welding process from a sensor (not shown) included in, for example, a wire feeding device300, or may be a known method, and a content of the method of detecting the completion of the welding process is not limited.

The main welding robots MC1a, MC1b, and so on as an example of the welding robot are connected to the robot control devices2a,2b, and so on so as to be able to communicate data with the robot control devices2a,2b, and so on. The main welding robots MC1a, MC1b, and so on execute the welding process instructed by the host device1under the control of the corresponding robot control devices2a,2b, and so on.

FIG.2is a diagram showing an internal configuration example of the host device1, the robot control device2a, and the reading device3according to the first embodiment. In order to make the description easy to understand, the monitor MN1and the input interface UI1are not shown inFIG.2, the main welding robot MC1aamong the main welding robots MC1a, MC1b, and so on is exemplified, and further, the robot control device2aamong the robot control devices2a,2b, and so on is exemplified.

The main welding robot MC1aexecutes the welding process instructed from the host device1under the control of the robot control device2a. The main welding robot MC1aperforms, for example, arc welding in the welding process. However, the main welding robot MC1amay perform welding (for example, laser welding) other than the arc welding. In this case, although not shown, a laser head may be connected to a laser oscillator via an optical fiber instead of a welding torch400. The main welding robot MC1aincludes at least a manipulator200, the wire feeding device300, a welding wire301, and the welding torch400.

The manipulator200includes an articulated arm, and moves each arm based on a control signal from a robot control unit25(see the following description) of the robot control device2a. Accordingly, the manipulator200can change a positional relationship between a workpiece Wk and the welding torch400(for example, an angle of the welding torch400with respect to the workpiece Wk) by the movement of the arm.

The wire feeding device300controls a feeding speed of the welding wire301based on a control signal (see the following description) from the robot control device2a. The wire feeding device300may include a sensor capable of detecting a remaining amount of the welding wire301.

The welding wire301is held by the welding torch400. When electric power is supplied from a power supply device4to the welding torch400, an arc is generated between a tip end of the welding wire301and the workpiece Wk, and the arc welding is performed. The illustration and description of a configuration and the like for supplying shielding gas to the welding torch400are omitted for the convenience of description.

The host device1generates the welding process execution command using each of the plurality of original workpieces by using the welding-related information input or set in advance by the user business operator, and transmits the execution command to the robot control device2a. The host device1includes at least a communication unit10, a processor11, and a memory12.

The communication unit10is connected to the robot control device2and the external storage ST so that data can be communicated among the communication unit10, the robot control device2a, and the external storage ST. The communication unit10transmits a welding process execution command (see the above description) generated by the processor11to the robot control device2a. The communication unit10receives the ID of the welded work transmitted from the robot control device2aand outputs the ID to the processor11. The welding process execution command may include, for example, a control signal for controlling each of the manipulator200, the wire feeding device300, and the power supply device4included in the main welding robot MC1a.

The processor11is configured using, for example, a central processing unit (CPU) or a field programmable gate array (FPGA), and performs various processing and control in cooperation with the memory12. Specifically, the processor11functionally implements a cell control unit13, an ID setting management unit14, a logical data generation unit15, and an ID selection unit16by referring to a program held in the memory12and executing the program.

The memory12includes, for example, a random access memory (RAM) as a workpiece memory used when processing of the processor11is executed, and a read only memory (ROM) for storing a program defining processing of the processor11. The RAM temporarily stores data generated or acquired by the processor11. A program that defines processing of the processor11is written into the ROM. The memory12stores the data of the welding-related information read from the external storage ST, data of secondary workpiece information (see the following description) including the ID of the selected welded workpiece (secondary workpiece), and the welding process logical data (seeFIGS.3and5) of the secondary workpiece generated by the processor11.

The cell control unit13generates the execution command for executing the welding process using the plurality of original workpieces defined (in other words, set) in the welding-related information based on the welding-related information stored in the external storage ST. The cell control unit13may generate a different welding process execution command for each welding process executed by each of the main welding robots MC1a, MC1b, and so on. The welding process execution command generated by the cell control unit13is transmitted to the corresponding robot control devices2a,2b, and so on via the communication unit10.

The ID setting management unit14sets the ID of the welded workpiece (secondary workpiece) output from the ID selection unit16as the ID of the welded workpiece (secondary workpiece) produced by the welding process using each of the plurality of original workpieces, and stores the ID in the memory12. The ID setting management unit14may store the ID of the welded workpiece (secondary workpiece) and the welding process logical data (see the following description) in the external storage ST in association with the information on the identification sign Q.

The logical data generation unit15uses the secondary workpiece information including the ID of the welded workpiece (secondary workpiece) transmitted from the robot control device (for example, the robot control device2a) to generate the welding process logical data indicating a relationship between the ID of the secondary workpiece and the ID of each of the plurality of original workpieces used in the welding process (for example, a temporal order in which the welding process is performed on each of the plurality of original workpieces) (seeFIGS.3and5). Details of the welding process logical data will be described later with reference toFIGS.3and5. The logical data generation unit15may store the ID of the welded workpiece (secondary workpiece) and the welding process logical data (seeFIG.3) in the external storage ST in association with the information on the identification sign Q.

After the welding process using the plurality of original workpieces is completed, the ID selection unit16sets, according to a predetermined rule, the ID of the welded workpiece (secondary workpiece) selected in advance before the welding process is performed. Here, the ID and the predetermined rule will be described. In the present specification, the predetermined rule used for the selection of the ID is a rule to be selected by the ID strength (that is, the ID is strong and the ID is weak), a rule to be randomly selected from the IDs set for the plurality of original workpieces used for the production of the welded workpiece, and a rule to generate a new ID different from the IDs of the plurality of original workpieces. The ID selection unit16selects or generates the ID of the welded workpiece based on any one of the rules set by the user business operator, and sets the ID.

In the present specification, the ID is constituted by, for example, a combination of a plurality of types of character codes. The types are, for example, alphabets and numbers, and are not limited thereto. For example, “ABC001XYZ999” is indicated as the ID of the original workpiece. Here, in order to make the description easy to understand, the ID is shown as a 12-digit character code formed of “three digits of alphabets”, “three digits of numerals”, “three digits of alphabets”, and “three digits of numerals”, whereas the ID is not limited to the configuration examples. Among the 12-digit character codes, for example, the upper three digits of alphabets may indicate codes of a company or a customer (for example, a supplier or a shipping destination), and other “three digits of numerals”, “three digits of alphabets”, and “three digits of numerals” may indicate serial numbers. The numbers of digits of numbers and alphabets are not limited to the same number of digits, and for example, different numbers of digits such as “TA001” and “RA001” shown inFIG.4may be set. Hereinafter, the rules for selecting or generating the ID of the welded workpiece will be described.

A rule for selecting the ID of the welded workpiece (secondary workpiece) according to ID strength will be described. As for the ID, the following two strength rules are defined as rules indicating the ID strength (that is, the ID is strong and the ID is weak). Hereinafter, the two strength rules will be described.

In a first strength rule, the ID selection unit16sets a division between an alphabet and a number for the ID of the original workpiece, and compares the strength of each part of the division. In a second strength rule, the ID selection unit16determines that, in one division between the alphabet or the number, the strength is stronger as the order of the alphabets is earlier and the strength is stronger as the number is larger. For example, it is determined that “A” is stronger than “B” in the alphabet and “2” is stronger than “1” in the number.

As a modification of the second strength rule, the ID selection unit27may determine that, in one division between the alphabet or the number, the strength is stronger as the order of the alphabets is later and the strength is stronger as the number is smaller. For example, it may be determined that “B” is stronger than “A” in the alphabet and “1” is stronger than “2” in the number.

Here, “ABC001XYZ999” and “ABD002XYW998” are shown as the IDs of the original workpieces to be compared. For example, the ID selection unit16provides divisions “ABC”, “001”, “XYZ”, and “999” for the ID “ABC001XYZ999”, and similarly provides divisions “ABD”, “002”, “XYW”, and “998” for the ID “ABD002XYW998”.

For example, the ID selection unit16compares the IDs of the segment parts provided in order from upper digits of the ID at any time, and determines that “ABC” is stronger than “ABD”, “001” is weaker than “002”, “XYZ” is weaker than “XYW”, and “999” is stronger than “998”. Furthermore, the ID selection unit16gives priority to the one with the stronger ID in the division of the upper digits and determines that the ID as a whole is strong. This is because, for example, the “alphabet” used in the upper digit of the ID does not often define the type of the original workpiece. Therefore, the ID selection unit16determines that the ID “ABC001XYZ999” is stronger than the ID “ABD002XYW998”. The above described strength rule is merely an example, and is not limited to the above described example, and it is needless to say that a rule for determining the ID strength may be provided.

Next, the rule for randomly selecting any of the IDs of the plurality of original workpieces and determining the selected ID as the ID of the welded workpiece (secondary workpiece) will be described. In other words, when the IDs of the plurality of original workpieces are “A” and “B” (seeFIG.3), the ID selection unit16randomly selects “A” or “B” as the ID of the welded workpiece (for example, the secondary workpiece). “Random” means that probability that the ID “A” is selected and probability that the ID “B” is selected at the time of selection may be equal (for example, 50% each) or may not be equal. A fact that the probabilities are not equal indicates that, for example, one of the IDs may be selected more unevenly or preferentially than other IDs.

Next, the rule for selecting or generating the new ID different from any ID among the IDs of the plurality of original workpieces and determining the ID as the ID of the welded workpiece (secondary workpiece) will be described. In other words, when the IDs of the plurality of original workpieces are “A” and “B”, the ID selection unit16generates a new ID such as “X” as the ID of the welded workpiece (for example, the secondary workpiece). Here, the original workpiece and the welded workpiece include a final weldment (for example, an n-th workpiece) produced by completing all the welding processes (for example, n welding processes (n is an integer of 3 or more)). The ID selection unit16may generate different new IDs for a plurality of welded workpieces to which the same welding process is completed. For example, the ID selection unit16may generate the ID of each of the three welded workpieces (secondary workpieces) produced by the execution of the secondary welding process, as “X”, “Y”, and “Z”.

The robot control device2acontrols the processing of the corresponding main welding robot MC1a(specifically, the manipulator200, the wire feeding device300, and the power supply device4) based on the welding process execution command sent from the host device1. The robot control device2aincludes at least a communication unit20, a processor21, and a memory22.

The communication unit20is connected to enable data communication between the host device1and the main welding robot MC1a. Although illustration is simplified inFIG.2, data is transmitted and received between the robot control unit25and the manipulator200, between the robot control unit25and the wire feeding device300, and between a power supply control unit26and the power supply device4via the communication unit20. The communication unit20receives the welding process execution command transmitted from the host device1. The communication unit20transmits the secondary workpiece information including the ID of the welded workpiece (the secondary workpiece) produced by the welding process to the host device1.

Here, the secondary workpiece information includes, in addition to the ID of the welded workpiece (the secondary workpiece), at least workpiece information (for example, the ID and name of the original workpiece, the welding portion of the original workpiece) including the IDs of the plurality of original workpieces used in the welding process, and welding conditions at the time of execution of the welding process. The welding conditions include, for example, a material and a thickness of the original workpiece, a material and a wire diameter of the welding wire301, a type of the shielding gas, a flow rate of the shielding gas, a set average value of a welding current, a set average value of a welding voltage, a feeding speed and a feeding amount of the welding wire301, the number of times of welding, and a welding time. In addition to these, for example, information indicating a type of welding process (for example, TIG welding, MAG welding, or pulse welding), and a moving speed and a moving time of the manipulator200may be included.

The processor21is configured with, for example, a CPU or an FPGA, and executes various processing and controls in cooperation with the memory22. Specifically, the processor21functionally implements a program generation unit23, a calculation unit24, the robot control unit25, and the power supply control unit26by referring to a program held in the memory22and executing the program.

The memory22includes, for example, a RAM as a workpiece memory used when the processing of the processor21is executed, and a ROM that stores a program defining the processing of the processor21. The RAM temporarily stores data generated or acquired by the processor21. The program that defines processing of the processor21is written in the ROM. The memory22stores data of the welding process execution command transmitted from the host device1, data of the secondary workpiece information including the ID of the welded workpiece (the secondary workpiece) generated by the welding process, and data of welding process logical data (seeFIGS.3and4) of the secondary workpiece generated by the processor21. The memory22stores a welding process program executed by the main welding robots MC1a, MC1b, and so on. The welding process program is a program that defines a specific procedure (process) of the welding process of joining the plurality of original workpieces using the welding conditions in the welding process. The program may be created in the robot control device2a, or may be created by the host device1, transmitted in advance, and stored in the robot control device2a.

The program generation unit23generates a welding process program to be executed by the main welding robot (for example, the main welding robot MC1a) using the workpiece information (for example, the ID, the name, and the welding portion of the original workpiece) of each of the plurality of original workpieces included in the execution command based on the welding process execution command transmitted from the host device1via the communication unit20. The program may include various parameters such as the welding current, the welding voltage, an offset amount, a welding speed, and a posture of the welding torch400for controlling the power supply device4, the manipulator200, the wire feeding device300, the welding torch400, and the like during the execution of the welding process. The generated program may be stored in the processor21or may be stored in the RAM in the memory22.

The calculation unit24performs various calculations. For example, the calculation unit24performs calculation or the like for controlling the main welding robot MC1a(specifically, each of the manipulator200, the wire feeding device300, and the power supply device4) controlled by the robot control unit25based on a welding process program generated by the program generation unit23.

The robot control unit25drives the main welding robot MC1a(specifically, each of the manipulator200, the wire feeding device300, and the power supply device4) based on the welding process program generated by the program generation unit23.

The power supply control unit26drives the power supply device4based on the welding process program generated by the program generation unit23and a calculation result of the calculation unit24.

The reading device3reads the identification sign Q assigned to the original workpiece used for the execution of the welding process or the welded workpiece produced by the execution of the welding process, and outputs the ID of the read workpiece. The reading device3is used by the user business operator. The reading device3includes at least a communication unit30, a processor31, a memory32, a reading unit33, and an operation unit35. A monitor34may or may not be included in the reading device3. When the monitor34is implemented as a configuration that is not included in the reading device3, the monitor34is connected to the reading device3so as to be capable of wireless or wired communication. The reading device3may include a speaker (not shown) when the reading device3outputs information on the ID of the workpiece by voice.

The communication unit30is connected to the host device1so as to be able to communicate data with the host device1. The communication unit30transmits, to the host device1, a command for requesting information on the ID of the workpiece to which the read identification sign Q is assigned, based on a reading result of the identification sign Q by the processor31. The communication unit30receives the ID of the welded workpiece transmitted from the host device1, and outputs the ID to the processor31.

The processor31is configured with, for example, a CPU or an FPGA, and executes various processing and controls in cooperation with the memory32. Specifically, the processor31implements functions of the processor31by referring to a program held in the memory32and executing the program.

The memory32includes, for example, a RAM as a workpiece memory used when the processing of the processor31is executed, and a ROM that stores a program defining the processing of the processor31. The RAM temporarily stores data generated or acquired by the processor31. The program that defines processing of the processor31is written in the ROM. Further, the memory32stores the information on the identification sign Q read from the reading unit33, the ID of the workpiece associated with the information on the identification sign Q transmitted from the host device1, and the like.

The reading unit33includes, for example, a camera for reading a two-dimensional barcode or a laser for reading a barcode. The reading unit33reads the identification sign Q assigned to the workpiece, and outputs information (data) read from the identification sign Q to the processor31.

The reading unit33implemented by using the camera is capable of reading, for example, the two-dimensional barcode, and includes at least a lens (not shown) and an image sensor (not shown). The image sensor is, for example, a solid-state imaging element of a charged-coupled device (CCD) or a complementary metal oxide semiconductor (CMOS), and converts an optical image formed on an imaging surface into an electric signal. The reading unit33implemented by the camera captures an image of the identification sign Q and performs image analysis on the captured identification sign Q. The reading unit33outputs information (data) on the identification sign Q acquired as a result of the image analysis to the processor31.

The reading unit33implemented by using the laser can optically read the identification sign Q (for example, the bar code, the IC tag, or the RF tag), and specifically, receives reflected light reflected by the identification sign Q by using the laser, and replaces a color included in the reflected light with a binary digital signal to acquire the information on the identification sign Q. The reading unit33includes a laser and a CCD reader capable of receiving the reflected light of the laser, or a laser and radio frequency identification (RFID). The reading unit33outputs information (data) on the barcode read by the CCD reader or information (data) on the IC tag, the RF tag, and the like read by the RFID to the processor31. When the reading unit33is implemented by the RFID, the reading unit33can read each of a plurality of IC tags or RF tags located in a range where radio waves reach at a time.

The monitor34serving as an example of an output unit is configured using, for example, a liquid crystal display (LCD) or an organic electroluminescence (EL). The monitor34outputs the ID of the workpiece received from the host device1. The monitor34may be a touch interface configured by a touch panel. In such a case, the monitor34has a function as an operation unit35, receives the input operation of the user business operator, generates a control signal based on the input operation, and outputs the control signal to the processor31.

The operation unit35receives the input operation by the user business operator and outputs the input operation to the processor31. The operation unit35generates the control signal based on the input operation by the user business operator and outputs the control signal to the processor31. The operation unit35may be implemented as a touch panel of the monitor34described above.

FIG.3is an explanatory diagram showing an example of an operation outline at the time of welding using a workpiece with an ID “A” and a workpiece with an ID “B”. In the example ofFIG.3, a process in which a welded workpiece (that is, the secondary workpiece Wk3) is produced by joining a circular workpiece Wk1(original workpiece) having the ID “A” and a square workpiece Wk2(original workpiece) having the ID “B” in one welding process is shown. As described above, the IDs “A” and “B” are, for example, 12-digit alphabets and numerals, but are collectively represented by one alphabetic character in order to make the description ofFIG.3easy to understand.

InFIG.3, the ID selection unit16selects the ID “A” as an ID read from each of the plurality of identification signs Q1and Q2assigned to the welded workpiece (that is, the secondary workpiece Wk3). Here, when the ID selection unit16determines that the ID “A” is stronger than the ID “B” based on strength information on the set ID, the ID selection unit16adopts and selects the stronger ID “A” as it is (that is, without changing) as the ID of the welded workpiece (that is, the secondary workpiece Wk3). The ID selection unit16may randomly adopt one of the ID strength or the ID “A” and the ID “B” (see the above description), and select the ID “A” as the ID of the welded workpiece (that is, the secondary workpiece Wk3). As described above, it is needless to say that the ID selection unit16may generate and adopt a new ID different from the ID of each of the workpieces Wk1and Wk2(original workpieces).

The ID setting management unit14sets the ID of the secondary workpiece Wk3selected by the ID selection unit16to the ID “A”. The ID setting management unit14associates the ID “A” set for the secondary workpiece Wk3with the identification sign Q1assigned to the workpiece Wk1(original workpiece) and the identification sign Q2assigned to the workpiece Wk2(original workpiece) as an ID to be output to the reading device3, and stores the ID “A” in the external storage ST.

When the reading device3reads the identification sign Q1assigned to the workpiece Wk1(original workpiece) before the first welding process, the reading device3receives the ID “A” of the workpiece Wk1(original workpiece) from the host device1, and outputs (displays) the ID “A” to a display screen R11. Similarly, when the reading device3reads the identification sign Q2assigned to the workpiece Wk2(original workpiece) before the first welding process, the reading device3receives the ID “B” of the workpiece Wk2(original workpiece) from the host device1, and outputs (displays) the ID “B” to a display screen R21. Further, the reading device3reads a plurality of identification signs Q1and Q2assigned to the secondary workpiece Wk3(welded workpiece) after the first welding process. At this time, the ID “A” of the secondary workpiece Wk3is set as the ID output to the reading device3by the plurality of identification signs Q1and Q2. Therefore, after the first welding process, the reading device3outputs (displays) the ID “A” on the display screen even when any of the plurality of identification signs Q1and Q2assigned to the secondary workpiece Wk3is read. Specifically, the reading device3outputs (displays) the ID “A” to the display screen R12when the identification sign Q1is read, and similarly outputs (displays) the ID “A” to the display screen R22when the identification sign Q2is read. In the display screen shown inFIG.3, only the information on the ID displayed for easy understanding of the description ofFIG.3is shown in a simplified manner. In the description ofFIG.3, an output example of the reading device3is described for all the identification signs assigned to each workpiece. However, since the ID set in each welding process is set to be unified into one ID, the reading device3may read at least one identification sign among the plurality of identification sign assigned to each workpiece.

Accordingly, in the welding system100according to the first embodiment, even if the ID of the workpiece (that is, the secondary workpiece Wk3) is randomly selected as the ID, if the ID “A” of the workpiece Wk1(original workpiece) and the ID “A” of the welded workpiece (that is, the secondary workpiece Wk3) are the same, it may be complicated to manage whether the ID “A” is the ID of the workpiece Wk1(original workpiece) or the secondary workpiece Wk3. Therefore, in the welding system100according to the first embodiment, for example, in the welding process using the workpiece Wk1(original workpiece) having the ID “A” and the workpiece Wk2(original workpiece) having the ID “B”, the logical data generation unit15in the host device1generates welding process logical data “A-B” logically indicating a mutual relationship between the ID “A” of the workpiece Wk1(original workpiece), the ID “B” of the workpiece Wk2(original workpiece), and the ID “A” of the secondary workpiece Wk3. The logical data generation unit15stores the generated welding process logical data “A-B” in association with the ID of each of the plurality of workpieces Wk1and Wk2(original workpieces) stored in the external storage ST.

The welding process logical data “A-B” shown inFIG.3is data having a logical structure in which the ID “A” is located at a higher level and the ID “B” is located at a lower level than the ID “A”. That is, the welding process logical data indicates, as viewed from the ID “A” of the secondary workpiece Wk3, which ID the original workpiece having is used and the secondary workpiece Wk3is produced by the welding process, and also indicates a list of IDs of the plurality of original workpieces used in the welding process and a temporal order in which the welding processes are executed when the plurality of welding processes exist. Accordingly, even after the welding process is completed, the user business operator can comprehensively grasp the data related to each of the original workpieces used for the production of the secondary workpiece Wk3without losing the information on the workpiece Wk2(original workpiece).

Further, the host device1generates a record TB1in which the ID “A” of the secondary workpiece Wk3and the welding process logical data “A-B” are associated with each other, and stores the record TB1in the external storage ST in association with each of the IDs of the plurality of workpieces Wk1and Wk2(original workpieces). The host device1may display, on the reading device3or the monitor MN1, a display screen showing the relationship between the ID “A” of the secondary workpiece Wk3and the welding process logical data “A-B”, or a display screen showing the relationship between the ID “B” of the secondary workpiece Wk3and the welding process logical data “A-B”. Accordingly, the user business operator can intuitively grasp details of the welding process that reaches the production of the secondary workpiece Wk3. Accordingly, even after the welding process is completed, the user business operator can comprehensively grasp the data related to each of the original workpieces used for the production of the secondary workpiece Wk3without losing the information on the workpiece Wk1(original workpiece).

The welding process logical data “A-B” is data having a logical structure in which the ID “B” is located at a higher level and the ID “A” is located at a lower level than the ID “B”. That is, the welding process logical data “A-B” indicates, as viewed from the ID “A” of the secondary workpiece Wk3, which ID the original workpiece having is used and the secondary workpiece Wk3is produced by the welding process, and also indicates a list of IDs of the plurality of original workpieces used in the welding process and a temporal order in which the welding processes are executed when the plurality of welding processes exist.

FIG.4is an explanatory diagram showing an example of display of a reading result of an ID during welding using the workpiece with the ID “A” and the workpiece with the ID “B”. The first welding process shown inFIG.4is the same process as the first welding process described with reference toFIG.3. InFIG.4, an ID output to the reading device3when the ID of each workpiece before and after the first welding process is read will be described. A timing at which the reading device3reads the ID of the workpiece may be only before the first welding process or only after the first welding process.

InFIG.4, the host device1sets a management ID “TA001” that is set and used when actually managed in a user business operator (see the following description) for the ID “A” of the workpiece Wk1(original workpiece) shown inFIG.3, and sets the management ID “RA001” for the ID “B” of the workpiece Wk2(original workpiece). The host device1further associates the management ID “TA001” set for the workpiece Wk1(original workpiece) with the identification sign Q1, and stores the management ID “TA001” in the external storage ST. Similarly, the host device1further associates the management ID “RA001” set for the workpiece Wk2(original workpiece) with the identification sign Q2, and stores the management ID “RA001” in the external storage ST.

InFIG.4, the reading device3reads the ID of the workpiece before and after the first welding process. Before the first welding process, the reading device3reads the identification sign Q1assigned to the workpiece Wk1(original workpiece) having the ID “A” and the identification sign Q2assigned to the workpiece Wk2(original workpiece) having the ID “B” before the first welding process.

When the reading device3reads the identification sign Q1assigned to the workpiece Wk1(original workpiece) before the first welding process, the reading device3receives the ID “A” of the workpiece Wk1(original workpiece) from the host device1, and displays the management ID “TA001” on the display screen SR11. The display screen SR11includes a plurality of buttons “Detail” and “Back”, and when the button “Detail” is selected (input) by the user business operator operation, the display screen SR11displays various kinds of information stored in association with the information on the identification sign Q1(data of the welding-related information related to the first welding process read from the external storage ST, customer (supplier) information on the workpiece Wk1(the original workpiece), and the like). When the button “Back” is selected (input), the reading device3shifts to a screen (not shown) for reading the identification sign.

Similarly, when the reading device3reads the identification sign Q2assigned to the workpiece Wk2(original workpiece) before the first welding process, the reading device3receives the ID “B” of the workpiece Wk2(original workpiece) from the host device1, and displays the ID “RA001” to the display screen SR21. The display screen SR21includes a plurality of buttons “Detail” and “Back”, and when the button “Detail” is selected (input) by the user business operator operation, the display screen SR21displays various kinds of information stored in association with the information on the identification sign Q2(data of the welding-related information related to the first welding process read from the external storage ST, customer (supplier) information on the workpiece Wk2(the original workpiece), and the like).

The host device1selects and sets the ID “TA001” as the ID of the secondary workpiece Wk3. The host device1associates the set ID “TA001” with the identification signs Q1and Q2assigned to each of the workpieces Wk1and Wk2(original workpieces) used for the production of the secondary workpiece Wk3as an ID to be output to the reading device3, and stores the ID “TA001” in the external storage ST. When the reading device3reads the identification sign Q1assigned to the secondary workpiece Wk3after the first welding process, the reading device3receives the ID “TA001” set in the secondary workpiece Wk3from the host device1, and when the identification sign Q2is read, the reading device3receives the ID “TA001” set in the secondary workpiece Wk3from the host device1. The reading device3displays the received ID “TA001”.

The display screen SR12when the identification sign Q1of the secondary workpiece Wk3is read includes the ID “TA001” of the secondary workpiece Wk3and the plurality of buttons “Detail” and “Back”, and when the button “Detail” is selected (input) by the user business operator, the display screen SR12displays the welding process logical data of the secondary workpiece Wk3stored in association with the information on the identification sign Q1, the various kinds of information stored in association with the information on the identification sign Q1(data of the welding-related information related to the first welding process read from the external storage ST, the customer (supplier) information on the workpiece Wk1(the original workpiece), and the like). Similarly, the display screen SR22when the identification sign Q2of the secondary workpiece Wk3is read includes the ID “TA001” of the secondary workpiece Wk3and the plurality of buttons “Detail” and “Back”, and when the button “Detail” is selected (input) by the user business operator, the display screen SR22displays the welding process logical data of the secondary workpiece Wk3stored in association with the information on the identification sign Q2, the various kinds of information stored in association with the information on the identification sign Q1(data of the welding-related information related to the first welding process read from the external storage ST, the customer (supplier) information on the workpiece Wk1(the original workpiece), and the like). When the button “Back” is selected (input), the reading device3shifts to a screen (not shown) for reading the identification sign.

Accordingly, the reading device3according to the first embodiment can visualize the IDs of the workpieces and the welding process logical data before and after the welding process without losing the information on each of the workpieces Wk1and Wk2(original workpieces). As described above, even when any of the plurality of identification signs assigned to the n-th workpiece is read, the host device1according to the first embodiment uniformly sets the same ID so that the same ID is output (displayed). Therefore, it is possible to reduce the possibility that all the identification signs assigned to the n-th workpiece are unreadable due to, for example, dirt, or breakage. Further, the user business operator can comprehensively grasp the information on the plurality of workpieces Wk1and Wk2(original workpiece) or the secondary workpiece Wk3(for example, the ID or the management ID for each workpiece, the welding-related information for each welding process, and the welding process logical data in the n-th workpiece) from the information displayed on the reading device3.

FIG.5is an explanatory diagram showing an example of an operation outline at the time of welding using the workpiece with the ID “A”, the workpiece with the ID “B”, the workpiece with the ID “C”, and the workpiece with the ID “D”. In the example ofFIG.5, a triangular parallelepiped workpiece Wk4(original workpiece) having the ID “C” and a pentagonal workpiece Wk5(original workpiece) having the ID “D” are joined together in a first welding process to produce a welded workpiece (that is, a secondary workpiece Wk6), a circular workpiece Wk1(original workpiece) having the ID “A” and a rectangular workpiece Wk2(original workpiece) having the ID “B” are joined together in a second welding process to produce a welded workpiece (that is, a secondary workpiece Wk3), and the secondary workpiece Wk3having the ID “A” and the secondary workpiece Wk6having the ID “C” are joined together in a third welding process to produce a welded workpiece (that is, a tertiary workpiece Wk7). Similarly, the IDs “A”, “B”, “C”, and “D” are formed of, for example, 12-digit alphabets and numerals, but are collectively represented by one alphabetic character in order to make the description ofFIG.5easy to understand.

The ID selection unit16inFIG.5selects an ID to be adopted for each of the secondary workpiece Wk6, the secondary workpiece Wk3, and the tertiary workpiece Wk7based on the ID strength rule. It is needless to say that the rule for selecting the ID is not limited thereto. In the example shown inFIG.5, it is assumed that the ID selection unit16determines that the ID “A” is stronger than the ID “B”. In this case, the ID selection unit16adopts and selects the stronger ID “A” as it is (that is, without changing) as the ID of the welded workpiece (that is, the secondary workpiece Wk3) which is a product of the first welding process. Similarly, it is assumed that the ID selection unit16determines that the ID “C” is stronger than the ID “D”. In this case, the ID selection unit16adopts and selects the stronger ID “C” as it is (that is, without changing) as the ID of the welded workpiece (that is, the secondary workpiece Wk6) which is the product of the second welding process. Furthermore, it is assumed that the ID selection unit16determines that the ID “A” is stronger than the ID “C”. In this case, the ID selection unit16adopts and selects the stronger ID “A” as it is (that is, without changing) as the ID of the welded workpiece (that is, the tertiary workpiece Wk7) which is the product of the third welding process.

However, if the ID “A” of the workpiece Wk1(original workpiece), the ID “A” of the welded workpiece (that is, the secondary workpiece Wk3), and the ID “A” of the tertiary workpiece Wk7are all the same, it may be complicated to manage which ID “A” is the workpiece Wk1(original workpiece), the secondary workpiece Wk3, or the tertiary workpiece Wk7. Therefore, in the welding system100according to the first embodiment, for example, in the first welding process to the third welding process, the host device1generates the welding process logical data (seeFIG.5) logically indicating a mutual relationship between the strongest ID “A” and other weak IDs “B”, “C”, and “D”, generates a record TB2in which the ID “A” of the tertiary workpiece Wk7and the welding process logical data are associated with each other, and stores the record TB2in the external storage ST.

The welding process logical data indicates, as viewed from the ID “A” of the tertiary workpiece Wk7, which ID the original workpiece having which ID is used in which the welding process the tertiary workpiece Wk7is used and produced, and also indicates a strength relationship of the IDs of the plurality of original workpieces used in each of the welding processes, and a temporal order in which each process is executed. For example, the welding process logical data indicates that the tertiary workpiece Wk7having the ID “A” is produced through three welding processes (the first welding process to the third welding process). In the second welding process, the workpiece Wk1(original workpiece) having the ID “A” and the workpiece Wk2(original workpiece) having the ID “B” are welded to each other, and since the ID “A” is stronger than the ID “B”, the ID “A” is selected as the ID of the secondary workpiece Wk3. In the first welding process, the workpiece Wk4(original workpiece) having the ID “C” and the workpiece Wk5(original workpiece) having the ID “D” are welded, and since the ID “C” is stronger than the ID “D”, the ID “D” is selected as the ID of the secondary workpiece Wk6. In the third welding process, the secondary workpiece Wk3having the ID “A” and the secondary workpiece Wk6having the ID “C” are welded to each other, and since the ID “A” is strong, the ID “A” is selected as the ID of the tertiary workpiece Wk7. In the welding process logical data, when viewed from the ID “A” of the tertiary workpiece Wk7, a position closer to the ID “A” indicates that a time at which the workpiece Wk1(original workpiece) or the secondary workpiece Wk3of the ID “A” is welded is older, and a position farther from the ID “A” indicates that the time at which the workpiece Wk1(original workpiece) or the secondary workpiece Wk3of the ID “A” is welded is newer. Accordingly, even after all of the plurality of welding processes are completed, the user business operator can comprehensively grasp the data on each of the plurality of original workpieces used for the production of the tertiary workpiece Wk7without losing the information on the original workpiece or the secondary workpiece of the weak ID in each welding process.

The ID of each workpiece displayed by reading each of the plurality of identification signs Q1to Q4assigned to each workpiece in the first welding process to the third welding process shown inFIG.5will be described. Before the first welding process, the reading device3transmits the information on the identification sign Q1assigned to the workpiece Wk1(original workpiece) to the host device1, reads the ID “A” of the workpiece Wk1(original workpiece), and displays the display screen R11including the read ID “A”. The reading device3transmits the information on the identification sign Q2assigned to the workpiece Wk2(original workpiece) to the host device1, reads the ID “B” of the workpiece Wk2(original workpiece), and displays the display screen R21including the read ID “B”. In the first welding process, the host device1selects (sets) the ID “A” as the ID of the secondary workpiece Wk3based on the ID strength rule. Therefore, the reading device3reads the same ID “A” even when any information on the plurality of identification signs Q1and Q2assigned to the secondary workpiece Wk3is transmitted to the host device1. The reading device3displays the display screen R12including the ID “A” when the identification sign Q1assigned to the secondary workpiece Wk3is read, and displays the display screen R22including the ID “A” when the identification sign Q2is read.

Before the second welding process, the reading device3transmits the information on the identification sign Q3assigned to the workpiece Wk4(original workpiece) to the host device1, reads the ID “C” of the workpiece Wk4(original workpiece), and displays the display screen R31including the read ID “C”. The reading device3transmits the information on the identification sign Q4assigned to the workpiece Wk5(original workpiece) to the host device1, reads the ID “D” of the workpiece Wk4(original workpiece), and displays the display screen R41including the read ID “D”. In the second welding process, the host device1selects (sets) the ID “C” as the ID of the secondary workpiece Wk6based on the ID strength rule. Therefore, the reading device3reads the same ID “C” even when any information on the plurality of identification signs Q1and Q2assigned to the secondary workpiece Wk6is transmitted to the host device1. The reading device3displays the display screen R32including the ID “C” when the identification sign Q3assigned to the secondary workpiece Wk6is read, and displays the display screen R42including the ID “C” when the identification sign Q4is read.

In the third welding process, the host device1selects (sets) the ID “A” as the ID of the tertiary workpiece Wk7based on the ID strength rule. After the third welding process, the reading device3transmits the information on the identification sign Q1assigned to the tertiary workpiece Wk7to the host device1, reads the ID “A” of the tertiary workpiece Wk7, and displays the display screen R13including the read ID “A”. Similarly, the reading device3displays the display screen R23including the ID “A” read from the identification sign Q2assigned to the tertiary workpiece Wk7, displays the display screen R33including the ID “A” read from the identification sign Q3, and displays the display screen R43including the ID “A” read from the identification sign Q4.

In the description ofFIG.5, an output example of the reading device3is described for all the identification signs assigned to each workpiece. However, since the ID set in each welding process is set to be unified into one ID, the reading device3may read at least one identification sign among the plurality of identification sign assigned to the welded workpiece in each of the welded workpieces (the secondary workpiece Wk6, the secondary workpiece Wk3, and the tertiary workpiece Wk7).

As described above, the reading device3according to the first embodiment can visualize the IDs of the workpieces and the welding process logical data before and after the welding process without losing information on the workpieces Wk1, Wk2, Wk4, and Wk5(original workpieces) and the plurality of secondary workpieces Wk3and Wk6(welded workpieces). As described above, even when any of the plurality of identification signs assigned to the n-th workpiece is read, the host device1according to the first embodiment uniformly sets the same ID so that the same ID is output (displayed). Therefore, it is possible to reduce the possibility that all the identification signs assigned to the n-th workpiece are unreadable due to, for example, dirt, or breakage. Further, the user business operator can comprehensively grasp the information related to each welding process (for example, the ID or the management ID for each workpiece, the welding-related information for each welding process, and the welding process logical data for the n-th workpiece) from the information displayed on the reading device3.

FIG.6is a diagram showing an example of a correspondence table XTB1between a selection ID and a management ID. When a business operator (hereinafter, referred to as the “user business operator”) who executes the welding process starts the welding process, an original workpiece such as a steel material used in the welding process may be supplied (in other words, may be outsourced) from the supplier in advance. For this reason, when the user business operator outsources the original workpiece such as the steel material, an ID is often assigned to the original workpiece in advance at an outsource destination. In the following description, the ID of the original workpiece assigned in advance in the outsource destination as described above is referred to as a “selection ID”. When the supplied original workpiece is assigned a selection ID unique to the outsource destination, the use of the selection ID may not be suitable in terms of the management of the user business operator.

Therefore, as shown inFIG.6, in the welding system100according to the first embodiment, when the selection ID is assigned to each of one or more original workpieces to be supplied from the outsource destination, the correspondence table XTB1(an example of the management table) indicating a relationship between the selection ID and the management ID of the user business operator is created by the user business operator and stored in the external storage ST. The correspondence table XTB1may be stored in the memory12of the host device1.

For example, in the correspondence table XTB1ofFIG.6, it is assumed that the user business operator supplies a plurality of original workpieces of the same type (for example, the same material supplied from the same supplier) from the outsource destination, and the management IDs “AAA001”, “BBB001”, “DDD001”, and the like corresponding to the selection IDs “RX85-1001”, “RX85-1002”, “RR90-0001”, and the like unique to the outsource destination are defined. “RX85-1001”, “RX85-1002”, “RR90-0001”, and so on are of the same type because “RX85” before hyphen in the ID is common, and are different from each other in branch number of “RX85” (number after the hyphen in the ID), so that the original workpieces (parts) are different.

(Operation of Welding System)

Next, an operation procedure of the ID management by the welding system100according to the first embodiment will be described with reference toFIG.7.FIG.7is a sequence diagram showing an operation procedure example of the ID management in the welding system100according to the first embodiment. In the description ofFIG.7, an operation procedure performed among the host device1, the robot control device2a, and the reading device3with respect to the welding process using the plurality of workpieces Wk1and Wk2(original workpieces) shown inFIG.3will be described as an example, and an operation procedure performed among other robot control devices2bwill be omitted. The workpiece A shown inFIG.7is the workpiece Wk1(original workpiece) having the ID “A”. Similarly, the workpiece B shown inFIG.7is the workpiece Wk2(original workpiece) having the ID “B”.

InFIG.7, the host device1acquires workpiece information (for example, the ID, the name, and the welding position of the original workpiece) including an ID of the plurality of workpieces Wk1and Wk2(original workpieces) to be subjected to the welding process (main welding) (St1), and selects (generates) an ID adopted as an ID of the secondary workpiece Wk3(that is, the welded workpiece) after the welding process based on the predetermined rule (St2). The ID of the secondary workpiece Wk3(the welded workpiece) selected (generated) here may be stored in the memory12of the host device1. The host device1transmits a welding process execution command including the workpiece information on the workpiece Wk1(original workpiece) and the workpiece information on the workpiece Wk2(original workpiece) to the robot control device2a(St3). Here, in the processing of step St2, it is assumed that, for example, the ID “A” of the workpiece Wk1(original workpiece) is selected as the ID of the secondary workpiece Wk3(welded workpiece).

When the robot control device2areceives the welding process execution command transmitted from the host device1, the robot control device2agenerates a welding process program executed by the main welding robot MC1ausing the workpiece information on each of the plurality of workpieces Wk1and Wk2(original workpieces) included in the execution command, and causes the main welding robot MC1ato execute the main welding according to the program (St4). The robot control device2adetermines the completion of the main welding (welding process) by the main welding robot MC1aby various known methods (St5), generates a main welding completion notification indicating the completion of the main welding every time the main welding of each of the plurality of workpieces Wk1and Wk2(original workpieces) is completed, and transmits the notification to the host device1(St6).

When the main welding completion notification indicating that the main welding is completed is received from the robot control device2a, the host device1sets the ID “A” selected (generated) in the processing of step St2to be output to the reading device3as the ID “A” of the secondary workpiece Wk3(welded workpiece), and generates the welding process logical data (seeFIGS.3and5) related to the secondary workpiece Wk3(welded workpiece) (St7). The host device1stores the ID “A” of the secondary workpiece Wk3(the welded workpiece) and the welding process logical data on the secondary workpiece Wk3(the welded workpiece) in association with each other in the external storage ST (St8).

The reading device3reads one of the identification signs Q1and Q2assigned to the secondary workpiece Wk3(welded workpiece) produced by the completion of the main welding (St9), and transmits the information on the read identification sign to the host device1(St10). Here, the read identification sign is referred to as the identification sign Q2.

The host device1refers to the external storage ST based on the information on the identification sign Q2received from the reading device3, and acquires the information on the ID “A” as the ID of the secondary workpiece Wk3(welded workpiece) associated with the information on the identification sign Q2(St11). The host device1transmits the acquired ID “A” of the secondary workpiece Wk3(welded workpiece) to the reading device3(St12).

The reading device3outputs (displays) the ID “A” of the secondary workpiece Wk3(welded workpiece) which is received from the host device1and is associated with the identification sign Q2read in the processing of step St9(St13).

As described above, the welding system100according to the first embodiment acquires the information on the IDs of the plurality of original workpieces to which the identification signs are assigned, respectively, the identification signs being assigned such that the information on the IDs (identifiers) are readable; selects, from the IDs of the plurality of original workpieces according to the predetermined rule, the ID to be set for the welded workpiece to be produced by the welding process using the plurality of original workpieces; and after the selection, in a case in which any identification sign among the identification signs assigned to the plurality of original workpieces is read by the reading device, outputs, as the ID of the welded workpiece, the information on the selected ID to the reading device.

Accordingly, the welding system100according to the first embodiment can support more efficient management by uniformly setting the IDs of the workpieces (in other words, the welded workpieces) produced in the welding process in which the plurality of original workpieces are joined or the like and outputting the IDs to the reading device3.

In the welding system100according to the first embodiment, identification signs of the plurality of original workpieces are assigned to the welded workpiece so as to be readable by the reading device3. Accordingly, the welding system100according to the first embodiment can acquire information on the plurality of original workpieces used in the production of the workpiece by reading at least one of the plurality of identification signs assigned to the workpiece even when the identification sign assigned in the welding process is contaminated, damaged, or the like, by assigning the plurality of identification signs in which the unified ID is set to the welded workpiece.

In the welding system100according to the first embodiment, each of the IDs includes a combination of a plurality of character codes, and is selected according to an ID strength rule defined for each type of character code. Specifically, the ID strength rule is defined for adopting an ID having a strong character code based on a comparison of strength among character codes constituting the IDs of the plurality of original workpieces included in the workpiece. The character codes include, for example, an alphabet and a number. Accordingly, the welding system100according to the first embodiment can easily set and manage the ID of the welded workpiece (for example, the secondary workpiece).

In the welding system100according to the first embodiment, each of the IDs includes a combination of a plurality of character codes. The predetermined rule includes randomly employing any one of the IDs of the plurality of original workpieces included in the welded workpiece in the selection of the ID to be set for the welded workpiece. Accordingly, the welding system100according to the first embodiment can easily set and manage the ID of the welded workpiece (for example, the secondary workpiece).

In the welding system100according to the first embodiment, each of the IDs includes a combination of a plurality of character codes. The predetermined rule includes adopting another ID different from the IDs of the plurality of original workpieces included in the welded workpiece in the selection of the ID to be set for the welded workpiece to be adopted. Accordingly, the welding system100according to the first embodiment can easily set and manage an ID different from any of the IDs of the plurality of original workpieces used for the production of the welded workpiece (for example, the secondary workpiece).

The reading device3according to the first embodiment is configured to read the identification signs assigned to the plurality of original workpieces to be used in the welding process performed by the welding system100, and includes the reading unit33configured to read the identification signs capable of outputting the information on the respective identifiers of the plurality of original workpieces, the processor31configured to acquire, based on an identification sign that has been read, the information on the identifier associated with the identification sign from the welding system, and the output unit (for example, the monitor34) configured to output the information on the identifier that has been acquired.

Accordingly, the reading device3according to the first embodiment can output the ID of the welded workpiece by reading the identification sign assigned to each workpiece. Therefore, the user business operator can easily confirm the ID of the welded workpiece.

Second Embodiment

In the welding system100according to the first embodiment, the example in which the identification sign Q is read by the reading device3(that is, the example in which the ID of the workpiece is read by the reading device3) is described. In the welding system100according to the second embodiment, an example will be described in which the main welding robot further includes a reading unit capable of reading information on the identification sign Q assigned to the workpiece, and the robot control device has an ID reading function.

FIG.8is a diagram showing an internal configuration example of the host device1and the robot control device2baccording to the second embodiment. The welding system100according to the second embodiment has substantially the same configuration as the welding system100according to the first embodiment. Therefore, the same components as those of the first embodiment are denoted by the same reference numerals, and a description thereof will be omitted. In the description ofFIG.8, in order to make the description easy to understand, illustration of the monitor MN1and the input interface UI1is omitted, the main welding robot MC1bamong the main welding robots MC1a, MC1b, and so on is exemplified, and further, the robot control device2bamong the robot control devices2a,2b, and so on is exemplified and described.

In the welding system100according to the second embodiment, the robot control device and the main welding robot having the function of reading the identification sign may be a part of the robot control device and the main welding robot selected by the user business operator. That is, in the welding system100according to the second embodiment, all of the robot control devices2a,2b, and so on and the main welding robots MC1a, MC1b, and so on do not have to have the function of reading the identification sign.

The main welding robot MC1bexecutes the welding process and the reading of the identification sign Q instructed from the host device1under the control of the robot control device2b. Before the welding process, the main welding robot MC1bexecutes reading of the identification sign Q assigned to each of the plurality of original workpieces using a reading unit33b, and transmits information on the read identification sign Q to the robot control device2b. After reading the identification sign Q, the main welding robot MC1bproceeds to the welding process, and performs, for example, arc welding in the welding process. The main welding robot MC1bmay perform welding (for example, laser welding) other than the arc welding.

The manipulator200includes an articulated arm, and moves each arm based on a control signal from the robot control unit25of the robot control device2b. Accordingly, the manipulator200can change the positional relationship between the reading unit33band the identification sign Q assigned to the workpiece Wk and the positional relationship between the workpiece Wk and the welding torch400by the movement of the arm.

The host device1generates an execution command for executing reading of the identification sign Q of each of the plurality of original workpieces based on the position information on the identification sign Q assigned to each of the plurality of original workpieces used in the welding process, and transmits the execution command to the robot control device2b. The host device1generates a welding process execution command using each of the plurality of original workpieces by using the welding-related information input or set in advance by the user business operator, and transmits the execution command to the robot control device2b.

The processor11in the host device1according to the second embodiment refers to the external storage ST based on a reading result of the identification sign Q read by the reading unit33b, and acquires the information on the ID of the workpiece to which the read identification sign Q is assigned. The processor11outputs the acquired workpiece ID to the monitor MN1. The processor11may transmit the acquired workpiece ID to the reading device3and cause the reading device3to display the acquired workpiece ID.

The reading unit33bincludes, for example, a camera for reading a two-dimensional barcode or a laser for reading a barcode. The reading unit33breads the identification sign Q assigned to the workpiece, and outputs information (data) read from the identification sign Q to the processor21.

As described above, the welding system100according to the second embodiment can not only read the identification sign Q using the reading device3but also read the identification sign Q using the main welding robot MC1b. Accordingly, the welding system100according to the second embodiment can read the IDs of a plurality of original workpieces or welded workpieces from the identification sign Q assigned to the workpiece Wk, for example, before, after, or both before and after the welding process, can display the read IDs of the workpieces on the reading device3owned by the user business operator, and can more efficiently read the IDs of the workpieces.

Since the ID of the workpiece can be read by the robot control device2band the reading device3, the user business operator can select which of the robot control device2band the reading device3reads the ID of the workpiece in accordance with a production process of the welded workpiece, such as a case where there are a plurality of welding processes or a case where the welding process is executed in a different cell.

Although the various embodiments are described above with reference to the drawings, it is needless to say that the present disclosure is not limited to such examples. It will be apparent to those skilled in the art that various alterations, modifications, substitutions, additions, deletions, and equivalents can be conceived within the scope of the claims, and it should be understood that such changes also belong to the technical scope of the present disclosure. Further, components in the various embodiments described above may be combined optionally in the range without deviating from the spirit of the invention.

The present application is based on Japanese Patent Application (Japanese Patent Application No. 2019-188157) filed on Oct. 11, 2019, and contents thereof are incorporated herein by reference.

The present disclosure is useful as an identifier management method and a reading device which support more efficient management of an identifier of a workpiece produced in a process such as welding.