JP5531870B2 - Robot system - Google Patents

Description

  The present invention relates to a robot system that processes a workpiece and assembles parts in each process while conveying the workpiece.

  This type of robot system includes a plurality of machine tools and robots, and in each process, machining and assembly of parts are performed on the workpiece by the machine tools and robot.

  In each process, the information of the previous process is referred to when performing the work of the own process. In general, equipment in each process is connected by a signal line, and information is transmitted by a PLC (Program Logic Controller) or a PC in conjunction with the movement of a workpiece. That is, the work information is shared by connecting the equipment of all the processes with the signal line.

  For example, in a robot system that includes a plurality of robots and performs work on a workpiece in cooperation with each other, correction data relating to the position of the workpiece is communicated from one robot to another robot via a communication cable ( Patent Document 1).

Japanese Patent Laid-Open No. 7-24765

  By the way, at the present time when high-mix low-volume production is becoming mainstream, equipment such as machine tools and robots are frequently removed from or added to the production line due to changes in processing content and process order. To do. Each time, it is necessary to disconnect or connect the signal lines connecting the facilities in each process, which requires a lot of work and may reduce the production efficiency of the product.

  The present invention has been made in view of such circumstances, and a main object of the present invention is to reduce equipment removal and additional labor in a robot system that performs work on a work in each process while transporting the work. Is.

  The present invention employs the following means in order to solve the above problems.

  1st invention is a robot system which works with respect to the said work at each process, conveying a work, Comprising: The delivery part which receives the work from a previous process, and delivers the work to a back process, The delivery A robot that delivers the workpiece from a section to a subsequent process, a working device that performs work on the workpiece in the delivery section, a storage medium that is provided in the robot and can read and write information wirelessly, and the robot in the previous process When delivering the workpiece to the delivery unit, a reading unit that wirelessly reads information stored in the storage medium in a previous process, and when the robot delivers the workpiece from the delivery unit, to the storage medium A writing unit for wirelessly writing information, and necessary information is added to the information read by the reading unit, and the information is read by the writing unit. Characterized in that it comprises a control unit for writing into the storage medium.

  According to the above configuration, in the robot system, work is performed on the workpiece in each process while the workpiece is being conveyed. At this time, the workpiece is delivered from the previous process to the delivery unit by the robot, and the work is performed on the workpiece by the work device in the delivery unit. In the delivery unit, the workpiece is delivered to the subsequent process by the robot. For this reason, it is possible to receive the workpiece from the previous process and deliver the workpiece to the subsequent process after performing operations such as processing and assembly of parts.

  Here, a storage medium capable of reading and writing information wirelessly is provided in the robot in the previous process, and when the robot in the previous process transfers the workpiece to the delivery unit, the information stored in the storage medium by the reading unit is stored. Read wirelessly. For this reason, the information (information regarding a workpiece | work) memorize | stored in the storage medium with the workpiece | work can be passed by radio | wireless from a previous process to an own process. In addition, a storage medium capable of reading and writing information wirelessly is provided in the robot of its own process, and when the robot of its own process delivers a work from the delivery unit, information is written to the storage medium by the writing unit wirelessly. For this reason, the information memorize | stored in the storage medium with the workpiece | work can be handed over wirelessly from a self process to a post process.

  At this time, necessary information is added to the information read from the storage medium of the previous process by the reading unit, and the information is written to the storage medium of the own process by the writing unit. For this reason, information can be moved from the previous process to the own process and to the subsequent process in the order of the storage medium of the previous process, the reading unit, the control unit, the writing unit, and the storage medium of the own process. Therefore, since information can be moved together with the workpiece wirelessly between the processes, there is no need to connect the processes with signal lines. As a result, it is not necessary to remove or connect the signal line when removing or adding equipment in each process, and the labor of the work can be reduced.

  Note that the reading unit and the writing unit may be constituted by a single read / write unit having both functions.

  In a second invention, in the first invention, the robot includes a hand unit for gripping and releasing the workpiece, the storage medium is provided in the hand unit, and the reading unit and the writing unit include the hand unit. It is provided in the vicinity of the delivery unit.

  According to the above configuration, in the robot, the storage medium is provided in the hand unit that holds and releases the workpiece. For this reason, when the hand part of the robot grips and moves the workpiece, the movement of the workpiece and the movement of the storage medium can be matched. Therefore, it becomes easy to move information together with the workpiece, and the integrity of the workpiece and the information related to the workpiece can be improved. As a result, it is possible to suppress the occurrence of a deviation in the correspondence between the workpiece and the information related to the workpiece.

  Further, the reading unit and the writing unit are provided in the vicinity of the delivery unit. For this reason, when the robot's hand unit grips the workpiece and transfers it to the delivery unit, the storage medium is brought closer to the delivery unit together with the workpiece. And the information memorize | stored in the storage medium as it is can be read wirelessly with the reading part provided in the delivery part vicinity. Further, when the hand portion of the robot grips the workpiece and delivers it from the delivery portion, the storage medium is brought close to the delivery portion together with the workpiece. Then, information can be written wirelessly to the storage medium as it is by a writing unit provided in the vicinity of the delivery unit. Accordingly, it is possible to further enhance the linkage between the robot's delivery operation and delivery operation and the reading and writing of information, and the efficiency of reading and writing information can be further improved. In short, as a basic operation in the robot system, the same function as the information transmission by the signal line can be achieved by the operation of moving the workpiece with respect to the delivery unit by the robot.

  In a third invention, in the first or second invention, the delivery unit includes a workpiece detection sensor that detects the presence of the workpiece, and the reading unit includes the workpiece in the delivery unit. When the robot in the previous process delivers the workpiece to the delivery unit, the information stored in the storage medium in the previous process is read wirelessly when it is detected by the workpiece detection sensor. And

  According to the said structure, it is detected by a workpiece | work detection sensor that a workpiece | work exists in a delivery part. Then, on condition that the workpiece is detected in the delivery unit, when the robot in the previous process delivers the workpiece to the delivery unit, information stored in the storage medium is read wirelessly. For this reason, when it is not detected that the workpiece exists in the delivery unit, even if the robot performs an operation of delivering the workpiece to the delivery unit, the information stored in the storage medium is not read. Therefore, only when the workpiece is actually delivered to the delivery unit, the information stored in the storage medium is read, and it is possible to suppress only the information from the previous process to the own process. . As a result, it is possible to suppress the occurrence of a deviation in the correspondence between the workpiece and the information related to the workpiece.

  In a fourth invention, in any one of the first to third inventions, the delivery unit includes a workpiece detection sensor that detects the presence of the workpiece, and the writing unit includes the workpiece in the delivery unit. On the condition that this is detected by the workpiece detection sensor, when the robot delivers the workpiece from the delivery unit, information is wirelessly written into the storage medium.

  According to the said structure, it is detected by a workpiece | work detection sensor that a workpiece | work exists in a delivery part. Then, on condition that it is detected that a workpiece exists in the delivery unit, information is wirelessly written in the storage medium when the robot delivers the workpiece from the delivery unit. For this reason, when it is not detected that the workpiece exists in the delivery unit, even if the robot performs an operation of delivering the workpiece from the delivery unit, information is not written in the storage medium. Therefore, only when the workpiece is actually delivered from the delivery unit, information is written to the storage medium, and it is possible to suppress only information from being delivered from the own process to the subsequent process. As a result, it is possible to suppress the occurrence of a deviation in the correspondence between the workpiece and the information related to the workpiece.

In a fifth invention, in any one of the first to fourth inventions, a robot detection sensor that detects that the robot in the previous process has approached the delivery unit,
When the robot in the previous process delivers the workpiece to the delivery unit on the condition that the robot detection sensor detects that the robot in the previous process has approached the delivery unit, Information stored in the storage medium in the previous process is read wirelessly.

  According to the above configuration, the robot detection sensor detects that the robot in the previous process has approached the delivery unit. Then, on condition that it is detected that the robot in the previous process has approached the delivery unit, the information stored in the storage medium is wirelessly read when the robot in the previous process delivers the workpiece to the delivery unit. . For this reason, when it is not detected that the robot in the previous process has approached the delivery unit, the information stored in the storage medium is not read. Therefore, the information stored in the storage medium is read only when the robot in the previous process actually approaches the delivery unit, and the reading accuracy by the reading unit can be improved. As a result, it is possible to prevent the process from being interrupted due to a failure in reading the information stored in the storage medium, and the correspondence between the workpiece and the information related to the workpiece from being shifted.

  According to a sixth invention, in any one of the first to fifth inventions, a robot detection sensor is provided for detecting that the robot has approached the delivery unit, and the writing unit is approached by the robot to the delivery unit. On the condition that this is detected by the robot detection sensor, when the robot delivers the workpiece from the delivery unit, information is written to the storage medium wirelessly.

  According to the above configuration, the robot detection sensor detects that the robot has approached the delivery unit. Then, on condition that it is detected that the robot has approached the delivery unit, information is wirelessly written to the storage medium when the robot delivers the work from the delivery unit. For this reason, when it is not detected that the robot has approached the delivery unit, information is not written to the storage medium. Therefore, information is written to the storage medium only when the robot actually approaches the delivery unit, and the writing accuracy by the writing unit can be improved. As a result, it is possible to prevent the process from being interrupted due to a failure in writing information to the storage medium and the correspondence between the workpiece and the information related to the workpiece from being shifted.

  In a seventh invention, in any one of the first to sixth inventions, the reading unit is stored in the storage medium in the previous process when the robot in the previous process delivers the workpiece to the delivery unit. The information stored in the storage medium is invalidated wirelessly after the information being read wirelessly.

  According to the above configuration, when the robot in the previous process transfers the workpiece to the transfer unit, the information stored in the storage medium in the previous process is read wirelessly by the reading unit and then stored in the storage medium. Information is invalidated wirelessly. For this reason, when writing information to the storage medium in the previous process fails next time, it is possible to prevent the information remaining in the storage medium from being delivered as information related to the workpiece. As a result, it is possible to suppress the occurrence of a deviation in the correspondence between the workpiece and the information related to the workpiece.

  In an eighth invention according to any one of the first to seventh inventions, the writing unit is configured to write information to the storage medium wirelessly when the robot delivers the workpiece from the delivery unit. The information stored in the storage medium is invalidated wirelessly.

  According to the above configuration, when the robot delivers the workpiece from the delivery unit, the information stored in the storage medium is invalidated wirelessly before the writing unit wirelessly writes the information on the storage medium. For this reason, when information writing to a storage medium fails next, it can suppress that the information which remained in the storage medium is handed over as information regarding a workpiece | work. As a result, it is possible to suppress the occurrence of a deviation in the correspondence between the workpiece and the information related to the workpiece.

  In a ninth invention, in any one of the first to seventh inventions, the writing unit is configured to write information in the storage medium wirelessly when the robot delivers the workpiece from the delivery unit. The information stored in the storage medium is wirelessly read, and the information is wirelessly written on the condition that the read information is invalid.

  According to the above configuration, when the robot delivers the workpiece from the delivery unit, the information stored in the storage medium is read wirelessly by the writing unit before the information is written to the storage medium wirelessly. Information is then written to the storage medium wirelessly on condition that the read information is invalid. For this reason, if the information stored in the storage medium has not yet been invalidated, that is, is valid, the information is not written to the storage medium even if the robot performs an operation of transferring the workpiece from the transfer unit. . Therefore, information is written to the storage medium only when the information stored in the storage medium is invalid. Therefore, when writing information into the storage medium fails, it is possible to prevent the information remaining in the storage medium from being delivered as information about the work. As a result, it is possible to suppress the occurrence of a deviation in the correspondence between the workpiece and the information related to the workpiece.

The top view of an assembly line provided with a some robot system. The enlarged side view which shows the mounting base of a workpiece | work, and its periphery structure. The block diagram which shows the electric constitution of the control system of a robot system. The flowchart which shows the process sequence of robot control, writing control, and reading control. The top view which shows the delivery aspect of a workpiece | work. The enlarged side view which shows the writing aspect of the information to a RFID tag. The top view which shows the delivery aspect of a workpiece | work. The enlarged side view which shows the reading aspect of the information from a RFID tag.

  Hereinafter, an embodiment embodied in an assembly line for processing a workpiece and assembling parts will be described with reference to the drawings.

  FIG. 1 is a plan view of an assembly line including a plurality of robot systems. As shown in the figure, the assembly line 10 includes a plurality of robot systems, that is, robot systems 20F, 20A, and 20B. These robot systems 20F, 20A, 20B are arranged in series at a predetermined interval, and are arranged from the upstream side along the flow of the workpiece W in this order.

  The robot system 20F includes a work device 21F, a reader / writer head 25F (controller 24F), a mounting table 22F, and a robot 30F. The work device 21F picks up the workpieces W stacked on the pallet one by one and places them on the mounting table 22F. The mounting table 22F (delivery unit) has a horizontal mounting surface, and the mounting surface is formed to have a size on which the workpiece W can be mounted. The operation of the work device 21F is controlled according to a predetermined program. For example, when the workpiece W on the mounting table 22F is transferred to the robot system 20A (post-process equipment), the next workpiece W is picked up from the pallet and Place on the mounting surface. The reader / writer head 25F is provided in the vicinity of the mounting table 22F. Specifically, the reader / writer head 25F is provided between the pallet on which the workpieces W are stacked and the mounting table 22F on the side of the mounting table 22F. Yes.

  Since the robot systems 20A and 20B basically have the same configuration, the robot system 20A will be described as an example here. In the robot system 20B, the subscript “B” is attached to the configuration corresponding to the robot system 20A instead of the subscript “A”. Also, the robot 30F of the robot system 20F has the same configuration as the robot 30A of the robot system 20A.

  The robot system 20A includes a work device 21A, a mounting table 22A, a reader / writer head 25A (controller 24A), a program logic controller (PLC) 50A, and a robot 30A (robot controller).

  The mounting table 22A (delivery unit) has the same configuration as the mounting table 22F described above in the robot system 20F. The mounting table 22A is disposed on the side of the robot system 20A. The mounting table 22A is a receiving position for receiving the work W from the robot system 20F (pre-process equipment) and a delivery position for delivering the work W to the robot system 20B (post-process equipment). Further, the mounting table 22A is a work table for performing work on the workpiece W in the robot system 20A (own process equipment).

  The work device 21A performs operations such as machining and assembly of parts on the workpiece W in the mounting table 22A. The working device 21A includes a processing unit that performs machining, a pallet in which components are stacked, a supply unit that supplies components, a robot unit that assembles components, and the like. Then, machining and assembly of parts are performed on the work W placed on the mounting table 22A as an operation of its own process.

  The reader / writer head 25A is provided in the vicinity of the mounting table 22A. Specifically, the reader / writer head 25A is provided on the side of the mounting table 22A on the opposite side of the robot 30A with the mounting table 22A interposed therebetween. The reader / writer head 25A is connected to the controller 24A and is a part that performs contacted communication with the wireless tag. The reader / writer head 25A includes a carrier transmitter, an amplifier, a transmission unit filter, an encoding unit, a modulation unit, a matching circuit, and the like as a transmission side circuit. As a circuit on the receiving side, a receiving unit filter, an amplifier, a demodulating unit, a binarization processing unit, a compounding unit, and the like are provided.

  The robot 30A is provided on the side near the mounting table 22A in the robot system 20A. The robot 30A is an articulated robot, and includes a hand portion 31A that chucks (grips) and unchucks (releases) the workpiece W. Then, the robot 30A picks up the workpiece W placed on the placement table 22A (delivery unit) of the robot system 20A and places it on the placement table 22B (delivery unit) of the robot system 20B. That is, the robot 30A delivers the workpiece W from the delivery unit of the robot system 20A (own process equipment) to the delivery unit of the robot system 20B (post process equipment). As described above, the robot system 20B basically has the same configuration as the robot system 20A. Then, the robot 30 </ b> B delivers the workpiece W from the delivery unit of the robot system 20 </ b> B (own process facility) to the reception unit of the post process facility.

  The robots 30F, 30A, and 30B are controlled by a robot controller (not shown). The robot controller includes a CPU, a ROM, a RAM, a control circuit, a communication interface, and the like. Timings at which the robot controller operates the robots 30F, 30A, and 30B are controlled by the PLCs 50F, 50A, and 50B, respectively.

  In such a configuration, when the workpiece W is placed on the placement surface of the placement table 22A, the PLC 50A causes the work device 21A to perform work on the workpiece W in conjunction therewith. Thereafter, the PLC 50A operates the robot 30A to deliver the workpiece W to the robot system 20B. Similarly, in the robot system 20B, the work is performed on the workpiece W, and the workpiece W is delivered to the post-process equipment.

  FIG. 2 is an enlarged side view showing a workpiece mounting table and its peripheral configuration. Here, from the standpoint of the robot system 20A, the relationship between these configurations and the robot 30A will be described.

  As shown in the figure, a work confirmation sensor 42A (work detection sensor) is provided on the mounting table 22A. The sensor 42A is a photoelectric sensor that emits visible light, infrared light, or the like as signal light from a light projecting unit and detects light reflected by a detection object by a light receiving unit, or a proximity sensor that uses electromagnetic induction, capacitance change, or the like. It is comprised by. The sensor 42A detects that the workpiece W has been placed on the placement table 22A.

  A chuck confirmation sensor 44A (robot detection sensor) is provided in the vicinity of the mounting table 22A. Specifically, when the robot 30F places the workpiece W on the placement table 22A, and when the robot 30A picks up the workpiece W from the placement table 22A, it can detect the hand portions 31F and 31A of the robots 30F and 30A. Sensors 44A are provided at various positions. The sensor 44A is configured by a photoelectric sensor or a proximity sensor, similarly to the workpiece confirmation sensor 42A. The sensor 44A detects that the hand units 31F and 31A of the robots 30F and 30A have approached the mounting table 22A.

  As described above, the reader / writer head 25A (reading unit, writing unit) is provided in the vicinity of the mounting table 22A. Specifically, when the robot 30F places the workpiece W on the placement table 22A and when the robot 30A picks up the workpiece W from the placement table 22A, the robot 30F faces the hand portions 31F and 31A of the robots 30F and 30A. A reader / writer head 25A is provided at the position. The reader / writer head 25A is supported by the housing of the controller 24A.

  In the hand portion 31A of the robot 30A, when the robot 30A picks up the workpiece W from the mounting table 22A, an RFID (Radio Frequency Identification) tag 33A is provided at a portion facing the reader / writer head 25A. The RFID tag 33A (storage medium) includes an antenna and an IC chip. The IC chip includes a power generation unit, a demodulation unit, a modulation unit, a memory unit, a control unit, and the like. The RFID tag 33A is provided on the side surface of the hand portion 31A, and when the robot 30A picks up the workpiece W from the mounting table 22A, the RFID tag 33A is positioned at substantially the same height as the reader / writer head 25A. At this time, the RFID tag 33A and the reader / writer head 25A have a distance at which data communication can be performed wirelessly.

  Also in the robot systems 20F and 20B, the workpiece mounting table and its peripheral configuration are the same as those of the robot system 20A.

  FIG. 3 is a block diagram showing an electrical configuration of a control system of the robot system 20A. Since the robot systems 20A and 20B basically have the same configuration, the robot system 20A will be described as an example here. The control systems of the robot systems 20F, 20A, and 20B are not connected to each other and have independent configurations.

  As shown in the figure, the reader / writer head 25A is connected to the controller 24A. The controller 24A includes a control unit, a data buffer, a memory, a data processing unit, and the like. The controller 24A causes the RFID tags 33F and 33A to read and write data by the reader / writer head 25A.

  The PLC 50A includes a CPU 51A, a memory 52A, a communication interface (I / O) 53A, and the like. A controller 24A, a chuck confirmation sensor 44A, a workpiece confirmation sensor 42A, and a robot controller 34A are connected to the I / O 53A. The PLC 50A (control unit) controls reading and writing of data by the reader / writer head 25A through the controller 24A based on signals input from the controller 24A, the chuck confirmation sensor 44A, and the workpiece confirmation sensor 42A. Further, the PLC 50A controls the robot 30A through the robot controller 34A based on these signals.

  In the present embodiment, the PLC 50A wirelessly reads information recorded on the RFID tag 33F by the reader / writer head 25A (reading unit) when the robot 30F of the robot system 20F delivers the workpiece W to the mounting table 22A. When the robot 30A delivers the workpiece W from the mounting table 22A, information is wirelessly written to the RFID tag 33A by the reader / writer head 25A (writing unit). In the RFID tag 33A, the product number, serial number, completion process information, pass / fail, etc. are recorded. In the robot system 20B, similar processing is executed by the PLC 50B.

  FIG. 4 is a flowchart showing processing procedures for robot control, write control, and read control. As shown in the figure, after the robot control and the writing control are executed in parallel, the robot control and the reading control are executed in parallel. Since the robot systems 20F, 20A, and 20B basically have the same configuration, the transfer of the workpiece W between the robot systems 20A and 20B will be described as an example here. The robot control is executed by the robot controller 34A of the robot 30A, the writing control is executed by the PLC 50A of the robot system 20A (own process equipment), and the read control is executed by the PLC 50B of the robot system 20B (post process equipment). Similar processing is executed between the robot systems 20F and 20A.

  First, the robot controller 34A starts to move the hand unit 31A of the robot 30A to the reader / writer head 25A of the robot system 20A based on the start signal from the PLC 50A (S11), and the hand unit 31A arrives at the reader / writer head 25A. (S12).

  In parallel with this, the PLC 50A confirms that the hand portion 31A of the robot 30A is in a state of chucking the workpiece W on the mounting table 22A (S51). Specifically, based on the detection signal of the chuck confirmation sensor 44A, it is detected that the hand unit 31A has approached the mounting table 22A, and the work W is placed on the mounting table 22A based on the detection signal of the work confirmation sensor 42A. Is detected.

  When it is confirmed that the hand unit 31A is in the state of chucking the workpiece W, the PLC 50A outputs an information disclosure command from the reader / writer head 25A to the RFID tag 33A through the controller 24A (S52). In other words, when it cannot be confirmed that the hand unit 31A is in a state of chucking the workpiece W, that is, when it is not detected that the hand unit 31A approaches the mounting table 22A, or the workpiece W is mounted on the mounting table 22A. If it is not detected, the PLC 50A does not output an information disclosure command from the reader / writer head 25A to the RFID tag 33A, and does not execute information writing processing to the RFID tag 33A thereafter.

  In parallel with this, the robot controller 34A chucks the workpiece W by the hand portion 31A of the robot 30A (S13), and activates a timer that measures the time until the chucking operation is stabilized (S14). During the operation of the timer, control for stabilizing the chuck operation in the robot 30A is executed. At this time, the RFID tag 33A provided in the hand portion 31A is in a state of facing the reader / writer head 25A. During the operation of the timer, data communication is executed between the RFID tag 33A and the reader / writer head 25A. Specifically, the RFID tag 33A discloses the recorded information in response to the information disclosure command from the reader / writer head 25A (S15).

  Subsequently, in response to the disclosure of information from the RFID tag 33A, the PLC 50A reads information recorded on the RFID tag 33A through the controller 24A (S53). Then, the PLC 50A determines whether or not unnecessary information remains in the RFID tag 33A (S54). Specifically, it is determined whether information read from the RFID tag 33A is invalid, that is, whether unnecessary information is invalidated in the RFID tag 33A. Specifically, when the information read from the RFID tag 33A includes a product number, serial number, completion process information, pass / fail, etc., it is determined that unnecessary information has not yet been invalidated and read. If the information does not exist or is a specific code, it is determined that unnecessary information is invalidated.

  In the above determination, when it is determined that unnecessary information remains in the RFID tag 33A (S54: NO), the PLC 50A stops the work device 21A and the robot 30A and notifies that (S58). On the other hand, when it is determined that unnecessary information does not remain in the RFID tag 33A (S54: YES), the PLC 50A causes the reader / writer head 25A to write and confirm information to the RFID tag 33A through the controller 24A. (S55). Specifically, information corresponding to the work W for which work in the robot system 20A has been completed is written to the RFID tag 33A by the reader / writer head 25A. This information is information obtained by adding information related to the work in the robot system 20A to the information corresponding to the work W for which the work in the robot system 20F has been completed.

  At this time, the timer is operating in the robot controller, and the information is written to the RFID tag 33A facing the reader / writer head 25A by the reader / writer head 25A (S16). In this data communication, an information disclosure command is transmitted from the reader / writer head 25A, and the RFID tag 33A discloses the written information (S17).

  Subsequently, in response to the disclosure of information from the RFID tag 33A, the PLC 50A reads the information recorded on the RFID tag 33A through the controller 24A, and confirms the read information (S55). Specifically, the controller 24A stores the read information.

  After the information is thus written and confirmed in the RFID tag 33A, the robot controller 34A stops the timer after the measurement time of the timer has elapsed (S18). That is, the control for stabilizing the chucking operation in the robot 30A ends. Subsequently, the robot controller 34A starts to move the hand portion 31A of the robot 30A to the reader / writer head 25B of the robot system 20B (S19).

  In parallel with this, the PLC 50A confirms that the hand portion 31A of the robot 30A picks up the workpiece W on the mounting table 22A (S56). Specifically, based on the detection signal of the chuck confirmation sensor 44A, it is detected that the hand unit 31A is in the state of approaching the mounting table 22A, and the workpiece W is loaded based on the detection signal of the workpiece confirmation sensor 42A. It detects that it is not mounted on the mounting base 22A.

  When it is confirmed that the hand unit 31A picks up the workpiece W, the PLC 50A determines whether the information written in the RFID tag 33A is normal (S57). In other words, when it cannot be confirmed that the hand unit 31A picks up the workpiece W, that is, when it is not detected that the hand unit 31A is close to the mounting table 22A, or the workpiece W is mounted on the mounting table 22A. If it is not detected that the error has not occurred, the PLC 50A does not execute the subsequent processing.

  In the above determination, when it is determined that the information written in the RFID tag 33A is not normal (S57: NO), the PLC 50A stops the work device 21A and the robot 30A and notifies that (S58). On the other hand, when it is determined that the information written in the RFID tag 33A is normal (S57: YES), the PLC 50A ends this series of writing control.

  Next, the robot control by the robot controller 34A and the reading control by the PLC 50B of the robot system 20B are executed in parallel.

  The robot controller 34A starts moving the hand portion 31A of the robot 30A to the reader / writer head 25B of the robot system 20B, and then arrives at the hand portion 31A to the reader / writer head 25B (S21).

  In parallel with this, the PLC 50B confirms that the hand unit 31A of the robot 30A has placed the workpiece W on the mounting table 22B (S61). Specifically, based on the detection signal of the chuck confirmation sensor 44B, it is detected that the hand unit 31A has approached the mounting table 22B, and the work W is placed on the mounting table 22B based on the detection signal of the work confirmation sensor 42B. Is detected.

  When it is confirmed that the hand unit 31A has placed the workpiece W, the PLC 50B outputs an information disclosure command from the reader / writer head 25B to the RFID tag 33A through the controller 24B (S62). In other words, when it cannot be confirmed that the hand unit 31A has placed the workpiece W, that is, when it is not detected that the hand unit 31A has approached the mounting table 22B, or the workpiece W is mounted on the mounting table 22B. If this is not detected, the PLC 50B does not output the information disclosure command from the reader / writer head 25B to the RFID tag 33A, and does not execute the subsequent information reading process from the RFID tag 33A.

  In parallel with this, the robot controller 34A unchucks the workpiece W by the hand portion 31A of the robot 30A (S22), and activates a timer that measures the time until the unchucking operation is stabilized (S23). During the operation of the timer, control for stabilizing the unchuck operation in the robot 30A is executed. At this time, the RFID tag 33A provided in the hand portion 31A is in a state of facing the reader / writer head 25B. During the operation of the timer, data communication is executed between the RFID tag 33A and the reader / writer head 25B. Specifically, the RFID tag 33A discloses the recorded information in response to the information disclosure command from the reader / writer head 25B (S24).

  Subsequently, in response to the disclosure of information from the RFID tag 33A, the PLC 50B reads information recorded on the RFID tag 33A through the controller 24B (S63). Specifically, information such as the product number, serial number, completion process information, and quality recorded in the RFID tag 33A is read.

  Subsequently, the PLC 50B causes the reader / writer head 25B to clear and confirm information of the RFID tag 33A through the controller 24B (S64). Specifically, the information recorded on the RFID tag 33A is cleared (erased) by the reader / writer head 25B. That is, the product number, serial number, completion process information, pass / fail information, etc. recorded on the RFID tag 33A is invalidated.

  At this time, the timer is operating in the robot controller 34A, and the above information is cleared by the reader / writer head 25B to the RFID tag 33A facing the reader / writer head 25B (S25). In this data communication, an information disclosure command is transmitted from the reader / writer head 25B, and the RFID tag 33A discloses the cleared information (S26).

  Subsequently, in response to the disclosure of information from the RFID tag 33A, the PLC 50B reads the information recorded on the RFID tag 33A through the controller 24B and confirms the read information (S64). Specifically, the controller 24B stores the read information.

  Thus, after the information of the RFID tag 33A is cleared and confirmed, the robot controller 34A stops the timer after the measurement time of the timer has elapsed (S27). That is, the control for stabilizing the unchucking operation in the robot 30A ends. Subsequently, the robot controller 34A moves the hand portion 31A of the robot 30A to a standby position between the mounting table 22A of the robot system 20A and the mounting table 22B of the robot system 20B (S28). Then, the robot controller 34A ends this series of robot control.

  In parallel with this, the PLC 50B confirms that the hand portion 31A of the robot 30A has delivered the workpiece W onto the mounting table 22B (S65). Specifically, based on the detection signal of the chuck confirmation sensor 44B, it is detected that the hand unit 31A is not in a state of approaching the mounting table 22B, and the workpiece W is mounted on the mounting table based on the detection signal of the work confirmation sensor 42B. It detects that it is mounted on 22B.

  After confirming that the hand unit 31A has delivered the workpiece W, the PLC 50B determines whether the information read from the RFID tag 33A and the cleared information are normal (S66).

  In the above determination, when it is determined that the information read from the RFID tag 33A is not normal or the cleared information is not normal (S66: NO), the PLC 50B stops the work device 21B and the robot 30B, A message to that effect is sent (S67). On the other hand, when it is determined that the information read from the RFID tag 33A and the cleared information are normal (S66: YES), the PLC 50B ends this series of reading control.

  FIG. 5 is a plan view showing a workpiece delivery mode. Since the robot systems 20F, 20A, and 20B basically have the same configuration, the transfer of the workpiece W between the robot systems 20A and 20B will be described as an example here.

  As shown in the figure, work is performed on the workpiece W by the work device 21A of the robot system 20A on the mounting table 22A. Based on the start signal from the PLC 50A, the robot 30A moves the hand portion 31A to the mounting table 22A and picks up the workpiece W. At this time, the RFID tag 33A provided on the hand unit 31A approaches the reader / writer head 25A to a communicable distance, and the information about the workpiece W is stored in the RFID tag 33A while the hand unit 31A chucks the workpiece W. Written. Thereafter, the information written in the RFID tag 33A is conveyed together with the workpiece W to the mounting table 22B of the robot system 20B.

  FIG. 6 is an enlarged side view showing a mode of writing information to the RFID tag. Here, a case where the workpiece W is delivered from the mounting table 22A of the robot system 20A will be described as an example.

  As shown in FIG. 6A, the workpiece W placed on the placement table 22A is detected by the workpiece confirmation sensor 42A. When the hand portion 31A moves to the mounting table 22A, the hand portion 31A is detected by the chuck confirmation sensor 44A. In this state, the workpiece W is chucked by the hand unit 31A, the timer is activated, and control for stabilizing the chucking operation is executed.

  If it can be confirmed that the hand unit 31A is in a state of chucking the workpiece W during the operation of the timer, data communication is performed between the reader / writer head 25A and the RFID tag 33A facing the reader / writer head 25A. That is, during the operation in which the hand unit 31A chucks the workpiece W, information regarding the workpiece W is written to the RFID tag 33A as it is.

  As shown in FIG. 6B, the operation of the timer is subsequently stopped, and the work W is picked up from the mounting table 22A by the hand unit 31A. In this state, the workpiece confirmation sensor 42A does not detect the workpiece W, and the chuck confirmation sensor 44A detects the hand portion 31A. When the hand unit 31A confirms that the workpiece W has been picked up from the mounting table 22A, data communication is performed between the reader / writer head 25A and the RFID tag 33A while facing each other. That is, it is determined whether or not the information written in the RFID tag 33A is normal. When the information is not normal, the work device 21A and the robot 30A are stopped, and when normal, the write control is terminated.

  FIG. 7 is a plan view showing a workpiece receiving mode. Since the robot systems 20F, 20A, 20B, and 20C basically have the same configuration, here, description will be given by taking as an example the reception of the workpiece W between the robot systems 20A and 20B.

  As shown in the figure, the workpiece 30 is transferred from the mounting table 22A of the robot system 20A to the mounting table 22B of the robot system 20B by the robot 30A. The robot 30A moves the hand unit 31A to the mounting table 22B and places the workpiece W thereon. At this time, the RFID tag 33A provided in the hand unit 31A approaches the reader / writer head 25B to a communicable distance, and the information about the workpiece W is received from the RFID tag 33A while the hand unit 31A is unchucking the workpiece W. Is read. Thereafter, work is performed on the work W by the work device 21B.

  FIG. 8 is an enlarged side view showing how information is read from the RFID tag. Here, a case where the workpiece W is delivered to the mounting table 22B of the robot system 20B will be described as an example.

  As shown to Fig.8 (a), the workpiece | work W mounted on the mounting base 22B is detected by the workpiece | work confirmation sensor 42B. When the hand portion 31A moves to the mounting table 22B, the hand portion 31A is detected by the chuck confirmation sensor 44B. In this state, the workpiece W is unchucked by the hand unit 31A, the timer is activated, and control for stabilizing the unchucking operation is executed.

  If it can be confirmed that the hand unit 31A is in the state of unchucking the workpiece W during the operation of the timer, data communication is performed between the reader / writer head 25B and the RFID tag 33A facing the reader / writer head 25B. That is, during the operation in which the hand unit 31A unchucks the workpiece W, information regarding the workpiece W is read from the RFID tag 33A as it is.

  As shown in FIG. 8B, the operation of the timer is subsequently stopped, and the work W is placed on the placement table 22B by the hand unit 31A. In this state, the workpiece W is detected by the workpiece confirmation sensor 42B, and the hand portion 31A is not detected by the chuck confirmation sensor 44B. When the hand unit 31A confirms that the workpiece W has been placed on the placing table 22B, data communication is performed between the reader / writer head 25B and the RFID tag 33A while facing each other. . That is, after the information recorded on the RFID tag 33A is read, the recorded information is cleared. Thereafter, it is determined whether the read information and the cleared information are normal. If the information is not normal, the work device 21B and the robot 30B are stopped. If the information is normal, the read control is terminated.

  The embodiment described above has the following advantages.

  An RFID tag 33F capable of reading and writing information wirelessly is provided in the robot 30F of the robot system 20F. When the robot 30F of the robot system 20F delivers the workpiece W to the mounting table 22A of the robot system 20A, the reader / writer head The information stored in the RFID tag 33F is read wirelessly by 25A. For this reason, the information stored in the RFID tag 33F together with the workpiece W can be transferred wirelessly from the robot system 20F to the robot system 20A. Further, an RFID tag 33A capable of reading and writing information wirelessly is provided in the robot 30A of the robot system 20A. When the robot 30A of the robot system 20A delivers the workpiece W from the mounting table 22A, the RFID tag is read by the reader / writer head 25A. Information is written to 33A wirelessly. For this reason, the information stored in the RFID tag 33A together with the workpiece W can be transferred wirelessly from the robot system 20A to the robot system 20B.

  At this time, necessary information is added to the information read from the RFID tag 33F of the robot system 20F by the reader / writer head 25A, and the information is written to the RFID tag 33A of the robot system 20A by the reader / writer head 25A. Therefore, information can be moved from the robot system 20F to the robot system 20A and then to the robot system 20B in the order of the RFID tag 33F of the robot system 20F, the reader / writer head 25A, the PLC 50A, and the RFID tag 33A of the robot system 20A. Accordingly, since information can be moved wirelessly together with the workpiece W between the robot systems, there is no need to connect the robot systems with signal lines. As a result, when removing or adding each robot system, it is not necessary to disconnect or connect the signal line, and the work can be reduced.

  According to the above configuration, the RFID tag 33A is provided in the hand portion 31A for chucking and unchucking the workpiece W in the robot 30A. For this reason, when the hand part 31A of the robot 30A chucks and moves the workpiece W, the movement of the workpiece W and the movement of the RFID tag 33A can be matched. Therefore, it becomes easy to move information together with the workpiece W, and the integrity of the workpiece W and the information related to the workpiece W can be improved. As a result, it is possible to suppress a deviation in the correspondence between the workpiece W and the information related to the workpiece W.

  Further, the reader / writer heads 25A and 25B are provided in the vicinity of the mounting tables 22A and 22B, respectively. For this reason, when the hand portion 31A of the robot 30A chucks the workpiece W and transfers it to the mounting table 22B, the RFID tag 33A is brought close to the mounting table 22B together with the workpiece W. Then, the information stored in the RFID tag 33A can be read wirelessly by the reader / writer head 25B provided in the vicinity of the mounting table 22B. Further, when the hand unit 31A of the robot 30A grips the workpiece W and delivers it from the mounting table 22A, the RFID tag 33A is brought close to the mounting table 22A together with the workpiece W. Then, information can be wirelessly written to the RFID tag 33A as it is by the reader / writer head 25A provided in the vicinity of the mounting table 22A. Therefore, it is possible to further enhance the linkage between the delivery operation and delivery operation of the robot 30A and the reading and writing of information, and the efficiency of reading and writing information can be further improved. In short, as a basic operation in the robot systems 20A and 20B, a function similar to information transmission by signal lines can be achieved by an operation of moving the workpiece W with respect to the mounting tables 22A and 22B by the robots 30A and 30B.

  The presence of the workpiece W on the mounting table 22B is detected by the workpiece confirmation sensor 42B. When the robot 30A of the robot system 20A delivers the workpiece W to the mounting table 22B on the condition that the workpiece W is detected on the mounting table 22B, information stored in the RFID tag 33A is stored. Read wirelessly. For this reason, when it is not detected that the workpiece W exists on the mounting table 22B, even if the robot 30A performs an operation of transferring the workpiece W to the mounting table 22B, the information stored in the RFID tag 33A is read. I can't. Therefore, only when the workpiece W is actually delivered to the mounting table 22B, the information stored in the RFID tag 33A is read, and only the information is delivered from the robot system 20A to the robot system 20B. Can be suppressed. As a result, it is possible to suppress a deviation in the correspondence between the workpiece W and the information related to the workpiece W.

  The presence of the workpiece W on the mounting table 22A is detected by the workpiece confirmation sensor 42A. Then, on condition that the workpiece W is detected on the mounting table 22A, when the robot 30A delivers the workpiece W from the mounting table 22A, information is written to the RFID tag 33A wirelessly. For this reason, when it is not detected that the workpiece W exists on the mounting table 22A, even if the robot 30A performs an operation of delivering the workpiece W from the mounting table 22A, information is not written to the RFID tag 33A. Therefore, only when the workpiece W is actually delivered from the mounting table 22A, information is written to the RFID tag 33A, and it is possible to suppress only the information from being delivered from the robot system 20A to the robot system 20B. As a result, it is possible to suppress a deviation in the correspondence between the workpiece W and the information related to the workpiece W.

  The chuck confirmation sensor 44B detects that the hand portion 31A of the robot 30A has approached the mounting table 22B. When the hand unit 31A of the robot 30A delivers the workpiece W to the mounting table 22B on the condition that it has been detected that the hand unit 31A of the robot 30A has approached the mounting table 22B, it is stored in the RFID tag 33A. Information is read wirelessly. For this reason, when it is not detected that the hand unit 31A of the robot 30A has approached the mounting table 22B, the information stored in the RFID tag 33A is not read. Therefore, the information stored in the RFID tag 33A is read only when the hand unit 31A of the robot 30A actually approaches the mounting table 22B, and the reading accuracy by the reader / writer head 25B can be improved. . As a result, it is possible to prevent the process from being interrupted due to a failure in reading the information stored in the RFID tag 33A, and the correspondence between the workpiece W and the information about the workpiece W from being shifted.

  The chuck confirmation sensor 44A detects that the hand portion 31A of the robot 30A has approached the mounting table 22A. Then, on condition that the hand unit 31A of the robot 30A has approached the mounting table 22B, when the hand unit 31A of the robot 30A delivers the workpiece W from the mounting table 22A, information is wirelessly transmitted to the RFID tag 33A. Written in. For this reason, when it is not detected that the hand unit 31A of the robot 30A approaches the mounting table 22A, information is not written to the RFID tag 33A. Therefore, information is written to the RFID tag 33A only when the hand portion 31A of the robot 30A actually approaches the mounting table 22A, and the writing accuracy by the reader / writer head 25A can be improved. As a result, it is possible to prevent the process from being interrupted due to a failure in writing information to the RFID tag 33A and the correspondence between the workpiece W and the information related to the workpiece W from being shifted.

  When the robot 30A of the robot system 20A delivers the workpiece W to the mounting table 22B, after the information stored in the RFID tag 33A of the robot system 20A is read wirelessly by the reader / writer head 25B, the RFID tag The information stored in 33A is invalidated wirelessly. For this reason, when information writing to the RFID tag 33A of the robot system 20A fails next time, it is possible to prevent information remaining on the RFID tag 33A from being delivered as information on the workpiece W. As a result, it is possible to suppress a deviation in the correspondence between the workpiece W and the information related to the workpiece W.

  When the robot 30A delivers the workpiece W from the mounting table 22A, the information stored in the RFID tag 33A is read wirelessly by the reader / writer head 25A before the information is written to the RFID tag 33A wirelessly. Then, information is written to the RFID tag 33A wirelessly on condition that the read information is invalid. For this reason, even if the information stored in the RFID tag 33A has not yet been invalidated, that is, is valid, even if the robot 30A performs the operation of delivering the workpiece W from the mounting table 22A, the RFID tag 33A Information is not written. Therefore, information is written into the RFID tag 33A only when the information stored in the RFID tag 33A is invalid. Therefore, when the information writing to the RFID tag 33A fails, it is possible to prevent the information remaining in the RFID tag 33A from being delivered as information on the workpiece W. As a result, it is possible to suppress a deviation in the correspondence between the workpiece W and the information related to the workpiece W.

  It is not limited to said embodiment, For example, it can also implement as follows. Note that the configuration described using one robot system as an example can be applied to other robot systems.

  In the case where only the product number and serial number are recorded on the RFID tag 33A, and the completion process information, quality or the like is not recorded, the robot system 20A does not add new information to the information read from the RFID tag 33F. The read information may be written in the RFID tag 33A as it is.

  When the information is not normally cleared, the information may be cleared and confirmed again while the reader / writer head 25B and the RFID tag 33A are facing each other. Similarly, when the information read after writing is not normal, the information may be written and confirmed again while the reader / writer head 25A and the RFID tag 33A are facing each other.

  In the above embodiment, the information recorded prior to the writing of information is read and the information is written on condition that the read information is invalidated. However, this condition may be omitted. it can. Even in that case, it is possible to prevent the accuracy of the information from being lowered by determining whether or not the information read after writing is normal.

  In the above embodiment, the information recorded in the RFID tag 33A is invalidated after reading the information. However, the information is recorded in the RFID tag 33A prior to the writing of the information when the work W is delivered. Information may be invalidated. Even in this case, the same effects as in the above embodiment can be obtained. Further, both invalidation processes may be executed.

  In the above embodiment, information is written to the RFID tag 33A on condition that the chuck confirmation sensor 44A detects that the hand unit 31A of the robot 30A has approached the mounting table 22A. In the above embodiment, information is written to the RFID tag 33A on condition that the work confirmation sensor 42A detects that the work W is placed on the placement table 22A. However, information may be written to the RFID tag 33A on condition that communication between the reader / writer head 25A and the RFID tag 33A is possible.

  In the above embodiment, the information recorded in the RFID tag 33A is read on condition that the chuck confirmation sensor 44B detects that the hand unit 31A of the robot 30A has approached the mounting table 22B. In the above embodiment, the information recorded on the RFID tag 33A is read on condition that the work confirmation sensor 42B detects that the work W is placed on the placement table 22B. However, information may be read from the RFID tag 33A on condition that communication between the reader / writer head 25B and the RFID tag 33A is possible.

  When the RFID tag 33A is provided in a portion other than the hand portion 31A in the arm of the robot 30A, in addition to the operation of chucking and unchucking the workpiece W by the mounting table 22A and the mounting table 22B, the RFID tag 33A It is preferable to carry out the operation over the reader / writer heads 25A and 25B. During the operation, information can be written to and read from the RFID tag 33A. Even with this configuration, when the robot 30A delivers the workpiece W from the mounting table 22A, information can be written to the RFID tag 33A by the reader / writer head 25A, and the robot 30A delivers the workpiece W to the mounting table 22B. At this time, information can be read from the RFID tag 33A by the reader / writer head 25B.

  The storage medium capable of wireless data communication with the reader / writer heads 25A and 25B is not limited to the RFID tag 33A, and other storage media that read and write information wirelessly, such as a non-contact IC card, may be employed.

  The robot system 20A is not limited to the configuration including the single work device 21A, and may be configured to include a plurality of work devices.

  The robot system 20A is not limited to the configuration including one mounting table 22A, but may be configured to include a plurality of mounting tables 22A. In that case, a reader / writer head 25A may be provided on each mounting table 22A, and the robot 30A may transport the workpiece W between the mounting tables 22A.

  The robot 30A only needs to be capable of transporting the workpiece W by chucking and unchucking, and any type of robot such as a vertical articulated robot or a horizontal articulated robot can be adopted. .

  DESCRIPTION OF SYMBOLS 10 ... Assembly line, 20A, 20B, 20F ... Robot system, 21A, 21B, 21F ... Working device, 22A, 22B, 22F ... Mounting table (delivery part), 25A, 25B, 25F ... Reader / writer head (reading part, writing) Part), 30A, 30B, 30F ... robot, 31A, 31B, 31F ... hand part, 33A, 33B, 33F ... RFID tag, 42A, 42B, 42F ... work confirmation sensor (work detection sensor), 44A, 44B, 44F ... Chuck confirmation sensor (robot detection sensor), 50A, 50B, 50F... PLC (control unit).

Claims (9)

A robot system that performs work on the workpiece in each process while conveying the workpiece,
A delivery unit that receives the workpiece from the previous process and delivers the workpiece to the subsequent process;
A robot that delivers the workpiece from the delivery unit to a subsequent process;
A working device for performing work on the workpiece in the delivery unit;
A storage medium provided in the robot and capable of reading and writing information wirelessly;
A reading unit that wirelessly reads information stored in the storage medium of the previous process when the robot of the previous process transfers the workpiece to the transfer unit;
A writing unit that wirelessly writes information to the storage medium when the robot delivers the workpiece from the delivery unit;
A control unit for adding necessary information to the information read by the reading unit and writing the information to the storage medium by the writing unit;
A robot system comprising: The robot includes a hand unit for gripping and releasing the workpiece,
The storage medium is provided in the hand unit,
The robot system according to claim 1, wherein the reading unit and the writing unit are provided in the vicinity of the delivery unit. A workpiece detection sensor that detects the presence of the workpiece in the delivery unit;
When the robot in the previous process delivers the workpiece to the delivery unit on the condition that the workpiece detection sensor detects that the workpiece is present in the delivery unit, The robot system according to claim 1 or 2, wherein the information stored in the storage medium is read wirelessly. A workpiece detection sensor that detects the presence of the workpiece in the delivery unit;
The writing unit wirelessly transmits information to the storage medium when the robot delivers the workpiece from the delivery unit on condition that the workpiece detection sensor detects that the workpiece exists in the delivery unit. The robot system according to any one of claims 1 to 3, wherein the robot system is written. A robot detection sensor for detecting that the robot in the previous process has approached the delivery unit;
When the robot in the previous process delivers the workpiece to the delivery unit on the condition that the robot detection sensor detects that the robot in the previous process has approached the delivery unit, The robot system according to any one of claims 1 to 4, wherein information stored in the storage medium in a previous process is read wirelessly. A robot detection sensor for detecting that the robot has approached the delivery unit;
The writing unit wirelessly transmits information to the storage medium when the robot delivers the workpiece from the delivery unit on condition that the robot detection sensor detects that the robot has approached the delivery unit. The robot system according to any one of claims 1 to 5, wherein the robot system is written.   The reading unit stores information stored in the storage medium in the previous process wirelessly when the robot in the previous process transfers the workpiece to the delivery unit, and then stores the information in the storage medium. The robot system according to claim 1, wherein the information is invalidated wirelessly.   The writing unit wirelessly invalidates information stored in the storage medium prior to wirelessly writing information to the storage medium when the robot delivers the workpiece from the delivery unit. The robot system according to any one of claims 1 to 7.   The writing unit wirelessly reads the information stored in the storage medium prior to writing the information to the storage medium wirelessly when the robot delivers the workpiece from the delivery unit, and the read The robot system according to any one of claims 1 to 7, wherein information is written to the storage medium wirelessly on condition that the information is invalid.

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