Control system, control method, control program, and transport device

Abstract

The present invention provides a control system, control method, control program, and conveying device that can reduce the possibility of machine tool and conveying device failures while continuing the machining schedules of multiple machine tools to the extent possible. [Solution] The control system comprises multiple machine tools and a conveying device for loading and unloading workpieces to and from the multiple machine tools. The conveying device loads and unloads workpieces to and from the multiple machine tools according to the processing schedule. The conveying device detects an abnormality occurring in any of the multiple machine tools (S11). The conveying device determines the open / closed state of the shutter in the machine tool where the abnormality was detected (S17, S27). If the shutter is open, the conveying device stops the drive processing for the multiple machine tools (S35). If the conveying device determines that the shutter is closed, it stops the drive processing for one machine tool and continues the drive processing for the other machine tools (S19, S29).

Description

Technical Field

[0001] The present invention relates to a control system, a control method, a control program, and a transfer device for controlling a plurality of machine tools and a transfer device that transfers workpieces to and from the plurality of machine tools.

Background Art

[0002] A transfer device for transferring workpieces to and from a plurality of machine tools is known. When a failure occurs in one of the plurality of machine tools in the machining line described in Patent Document 1, the process that the failed machine tool is in charge of is executed by another machine tool.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] It is desirable that the machining schedules of a plurality of machine tools be continued as much as possible even when machining at one machine tool is interrupted. For this reason, it is also desirable that the transfer device that transfers workpieces to and from the plurality of machine tools be driven so that machining continues at other machine tools excluding the one machine tool where machining has been interrupted. On the other hand, depending on the type of abnormality that causes the interruption of machining, it may be desirable to stop the driving of the transfer device to stop all machining of the plurality of machine tools.

[0005] For example, the loading and unloading of workpieces by a conveying device may be performed by opening a shutter installed at the loading / unloading entrance of a machine tool. In this case, an abnormality detected with the shutter open may be an abnormality caused by the conveying device during workpiece loading or unloading. If machining is interrupted on one machine tool due to such an abnormality, there is a problem that the machine tool and the conveying device may malfunction if the conveying device is driven to continue machining on another machine tool.

[0006] The object of the present invention is to provide a control system, control method, control program, and conveying device that can reduce the possibility of machine tool and conveying device failure while continuing the machining schedules of multiple machine tools to the extent possible. [Means for solving the problem]

[0007] A control system according to a first aspect of the present invention is a control system that controls a plurality of machine tools that perform processing on workpieces brought in through an entrance / exit with a shutter for opening and closing an entrance / exit for loading and unloading workpieces, and a transport device for loading and unloading workpieces to the plurality of machine tools, and is characterized by executing a drive process for loading and unloading the workpieces to the plurality of machine tools by the transport device according to a predetermined processing schedule, a detection process for detecting an abnormality that has occurred in any of the plurality of machine tools, a first determination process for determining the open / closed state of the shutter in the machine tool in which the abnormality was detected by the detection process, a first control process for stopping the drive process to the plurality of machine tools if the first determination process determines that the shutter is in an open state, and a second control process for stopping the drive process to the one machine tool and continuing the drive process to the other machine tools if the first determination process determines that the shutter is in a closed state.

[0008] The control system stops the drive process for multiple machine tools if the shutter of one machine tool where an abnormality has been detected is open. This reduces the possibility of failure of multiple machine tools and conveying equipment. On the other hand, if the shutter of one machine tool where an abnormality has been detected is closed, the control system continues the drive process for the other machine tools. This allows the control system to continue the machining schedule as much as possible.

[0009] In the present invention, the detection process may detect a machining abnormality that occurred during the machining of the workpiece in any of the plurality of machine tools as the abnormality. In this case, if a machining abnormality occurs in any of the plurality of machine tools, the control system can control the plurality of machine tools according to the state of the shutter.

[0010] In the present invention, the detection process may detect a reset stop that stops the machining of the workpiece by one machine tool as the abnormality. In this case, if a reset stop occurs in multiple machine tools, the control system can drive the multiple machine tools according to the state of the shutters.

[0011] In the present invention, a second determination process may be performed to determine whether an operation to emergency stop the conveying device or one machine tool has been performed, and a third control process may be performed to stop the drive process for the multiple machine tools, regardless of the determination result of the first determination process, if the second determination process determines that the operation has been performed. If an operation to emergency stop the conveying device or one machine tool has been performed, it is highly likely that it will be difficult to continue the machining schedule with the multiple machine tools. Therefore, the control system stops the drive process for the multiple machine tools in such a case. This allows the control system to quickly stop the machining schedule.

[0012] A control method according to a second aspect of the present invention is a control method for controlling a plurality of machine tools that perform processing on workpieces brought in through an entrance / exit with a shutter for opening and closing an entrance / exit for loading and unloading workpieces, and a conveying device for loading and unloading workpieces to the plurality of machine tools, the method comprising: a drive step for loading and unloading the workpieces to the plurality of machine tools by the conveying device according to a predetermined processing schedule; a detection step for detecting an abnormality occurring in any of the plurality of machine tools; a first determination step for determining the open / closed state of the shutter in the machine tool in which the abnormality was detected by the detection step; a first control step for stopping the drive step for the plurality of machine tools if it is determined in the first determination step that the shutter is in an open state; and a second control step for stopping the drive step for the one machine tool and continuing the drive step for the other machine tools if it is determined in the first determination step that the shutter is in a closed state. According to the second aspect, the same effects as the first aspect can be achieved.

[0013] A control program according to a third aspect of the present invention causes a computer that controls a plurality of machine tools equipped with shutters for opening and closing an entrance / exit for loading and unloading workpieces, and which perform processing on the workpieces loaded through the entrance / exit, and a transport device for loading and unloading the workpieces to and from the plurality of machine tools, to execute a drive process for loading and unloading the workpieces to and from the plurality of machine tools by the transport device, according to a predetermined processing schedule, a detection process for detecting an abnormality occurring in any of the plurality of machine tools, a first determination process for determining the open / closed state of the shutter in the machine tool in which the abnormality was detected by the detection process, a first control process for stopping the drive process for the plurality of machine tools if the first determination process determines that the shutter is in an open state, and a second control process for stopping the drive process for the one machine tool and continuing the drive process for the other machine tools if the first determination process determines that the shutter is in a closed state. According to the third aspect, the same effects as the first aspect can be achieved.

[0014] A fourth aspect of the present invention is a conveying device that includes a shutter for opening and closing an entrance / exit for loading and unloading workpieces, and is a conveying device that loads and unloads workpieces to a plurality of machine tools that process the workpieces loaded through the entrance / exit, and is characterized by performing the following: a drive process for loading and unloading the workpieces to the plurality of machine tools according to a predetermined processing schedule; a detection process for detecting an abnormality occurring in any of the plurality of machine tools; a first determination process for determining the open / closed state of the shutter in the machine tool in which the abnormality was detected by the detection process; a first control process for stopping the drive process to the plurality of machine tools if the first determination process determines that the shutter is in an open state; and a second control process for stopping the drive process to the one machine tool and continuing the drive process to the other machine tools if the first determination process determines that the shutter is in a closed state. The fourth aspect can achieve the same effects as the first aspect. [Brief explanation of the drawing]

[0015] [Figure 1] This is a perspective view showing control system 1. [Figure 2] This is a perspective view showing the conveying device 1C. [Figure 3] This is a block diagram showing the electrical configuration of machine tools 1A and 1B and conveying device 1C. [Figure 4] This is a diagram showing the drive process. [Figure 5] This is a flowchart of the monitoring process. [Modes for carrying out the invention]

[0016] A control system 1 according to an embodiment of the present invention will be described. The drawings to be referred to are used to explain the technical features that can be adopted by the present invention. The configurations, controls, etc. described in the drawings are not intended to be limited thereto, but are merely illustrative examples. In the following description, the left and right, front and back, and up and down indicated by arrows in the drawings are used. The left and right directions, up and down directions, and front and back directions are the X-axis direction, Z-axis direction, and Y-axis direction of the machine tools 1A and 1B, respectively.

[0017] <Overview of the control system 1> As shown in FIG. 1, the control system 1 includes machine tools 1A and 1B, and a transfer device 1C. The machine tools 1A and 1B perform various machining operations on the workpiece. The various machining operations include hole drilling using a drill, tap, etc., and side surface machining using an end mill, milling cutter, etc. The operation of the machine tools 1A and 1B performing various machining operations on the workpiece is referred to as a "machining operation". The transfer device 1C transfers the workpiece in and out of the machine tools 1A and 1B.

[0018] The machine tool 1A is located to the left of the transfer device 1C. The machine tool 1B is located to the right of the transfer device 1C. The machine tools 1A and 1B, and the transfer device 1C are arranged side by side in the left and right direction.

[0019] The machine tool 1A has a main body 20 and a housing 30.

[0020] The main body 20 includes a base 21, a column 22, a Z-axis movement mechanism, a spindle head 23, a spindle 24, a table device 25, a tool changer 26, and a control box 27. The base 21 is a substantially rectangular parallelepiped-shaped metal base. The column 22 is fixed to the upper rear of the base 21. The Z-axis movement mechanism is arranged on the front surface of the column 22. The Z-axis movement mechanism moves the spindle head 23 in the Z-axis direction in response to the drive of the Z-axis motor.

[0021] The spindle 24 is arranged inside the spindle head 23. The spindle 24 has a mounting hole at its lower end. The spindle 24 mounts a tool holder in the mounting hole and rotates in response to the drive of the spindle motor. The tool holder holds the tool 29.

[0022] The table device 25 includes a Y-axis moving mechanism, a Y-axis table 25A, a table 25B, an X-axis moving mechanism, etc. The Y-axis moving mechanism is arranged on the upper surface of the base 21. The Y-axis moving mechanism moves the Y-axis table 25A in the Y-axis direction according to the drive of the Y-axis motor.

[0023] The X-axis moving mechanism is arranged on the upper surface of the Y-axis table 25A. The X-axis moving mechanism moves the table 25B in the X-axis direction according to the drive of the X-axis motor. Therefore, the table 25B can be moved in the X-axis direction and the Y-axis direction on the base 21 by the X-axis moving mechanism and the Y-axis moving mechanism.

[0024] Three pallet clamps 250 are fixed to the table 25B. The pallet clamp 250 fixes the pallet P shown in FIG. 2 on the table 25B. In the state where the pallet P is fixed on the table 25B, the three pallet clamps 250 are inserted into each of the three holes on the bottom surface of the pallet P.

[0025] The tool changer 26 is arranged on the front side of the spindle head 23 and includes a tool magazine 26A. The tool magazine 26A has a plurality of grip arms 260 arranged in a circular shape on its outer periphery. The grip arm 260 grips the tool holder. The tool changer 26 has a magazine motor at the upper part. The magazine motor rotates the tool magazine 26A. [[ID=一三]]

[0026] The control box 27 is fixed to the rear side of the column 22 and houses the numerical control device 10 shown in FIG. 3. The numerical control device 10 controls the Z-axis motor, the spindle motor, the X-axis motor, the Y-axis motor, the magazine motor, and an opening / closing motor described later respectively. The numerical control device 10 relatively moves the workpiece attached to the pallet P held on the table 25B and the tool 29 attached to the spindle 24 to perform various processes on the workpiece.

[0027] The housing 30 prevents chips generated during machining by the machine tool 1A and the scattering of the cleaning liquid of the machine tool 1A. The housing 30 has a cover 31 and a shutter 32.

[0028] The cover 31 has a box shape and surrounds the main body 20. An entrance / exit 310 is formed in the wall 31N of the cover 31 that is close to the conveying device 1C. Wall 31N is the right wall of the cover 31.

[0029] The shutter 32 is installed in the wall 31N. The shutter 32 moves vertically by an opening / closing motor. By moving vertically, the shutter 32 can open and close the loading / unloading entrance 310.

[0030] The state in which the shutter 32 opens the loading / unloading entrance 310 is called the "open state". The state in which the shutter 32 closes the loading / unloading entrance 310 is called the "closed state".

[0031] The configuration of machine tool 1B is the same as that of machine tool 1A. Of the housing 30 of machine tool 1B, the wall 31N adjacent to the conveying device 1C is the left wall of cover 31.

[0032] As shown in Figure 2, the transport device 1C has a robot arm 40 and a housing 50.

[0033] The robot arm 40 is a known articulated industrial robot. The robot arm 40 includes a base 41, a plurality of rotary joints 42, a plurality of links 43, a ball joint 44, and an end effector 45. The plurality of rotary joints 42 and the plurality of links 43 are referred to as the "arm section 4A".

[0034] The arm section 4A rotates around the base 41. Multiple links 43 extending from the base 41 are connected by multiple rotary joints 42. As each of the rotary joints 42 rotates, the multiple links 43 move freely. An end effector 45 is connected to the tip of the arm section 4A via a ball joint 44. The end effector 45 is detachable from the pallet P.

[0035] The housing 50 has a cover 51 and a support base 52.

[0036] The cover 51 has a box shape and surrounds the robot arm 40. An entrance 56L is formed in the left wall 51L of the cover 51. The entrance 56L is located to the right of the entrance 310 of the machine tool 1A. An entrance 56R is formed in the right wall 51R of the cover 51. The entrance 56R is located to the left of the entrance 310 of the machine tool 1B.

[0037] A control panel 57 is positioned on the front of the front wall 51F of the cover 51. The control panel 57 includes a display 57A and an operating unit 57B. Various screens are displayed on the display 57A. Various inputs, instructions, settings, etc., are input to the operating unit 57B.

[0038] The support base 52 includes a front support base 52F and a rear support base 52B. The front support base 52F is fixed to the rear surface of the front wall 51F of the cover 51. The rear support base 52B is fixed to the front surface of the rear wall 51B of the cover 51.

[0039] The front support base 52F and the rear support base 52B each consist of five plates arranged vertically. Multiple pallets P are placed on the top surface of the five plates of the front support base 52F and the rear support base 52B. The front support base 52F and the rear support base 52B function as shelves for the pallets P. The pallets P, while placed on the front support base 52F and the rear support base 52B, are housed inside the cover 51.

[0040] <Electrical Configuration> Referring to Figure 3, the electrical configurations of machine tools 1A and 1B, and conveying device 1C will be described.

[0041] The transport device 1C includes a control unit 60, a display 57A, an operating unit 57B, communication interfaces 63 and 64, and a motor assembly 40A. The motor assembly 40A includes various motors that drive the base 41, rotary joint 42, ball joint 44, and end effector 45 of the robot arm 40. Hereinafter, the interface will be referred to as "I / F".

[0042] The control unit 60, display 57A, operation unit 57B, communication I / F 63, 64, and motor assembly 40A are electrically connected.

[0043] The control unit 60 includes a CPU 61 and a memory 62. The CPU 61 provides overall control of the transport device 1C. The memory 62 stores the drive program, processing schedule, monitoring program, set values, various parameters, etc., for which the CPU 61 executes processing. The drive program is a program for executing the drive processing shown in Figure 4. The monitoring program is a program for executing the monitoring processing shown in Figure 5.

[0044] Communication I / F63 is a connection device for communicating with machine tool 1A. Communication I / F64 is a connection device for communicating with machine tool 1B.

[0045] Each numerical control device 10 of machine tools 1A and 1B includes a control unit 70, a display 73, an operating unit 74, a communication interface 75, and a motor assembly 76. The motor assembly 76 includes an X-axis motor, a Y-axis motor, a Z-axis motor, a spindle motor, a magazine motor, an opening / closing motor, etc.

[0046] The control unit 70, display 73, operation unit 74, communication interface 75, and motor assembly 76 are electrically connected.

[0047] The control unit 70 includes a CPU 71 and a memory 72. The CPU 71 provides overall control of the numerical control device 10. The memory 72 stores processing programs, NC programs, setting values, various parameters, etc., for which the CPU 71 executes processing. The NC program describes the machining operations of the machine tools 1A and 1B using multiple control commands in a predetermined programming language.

[0048] The display 73 is a device that displays various screens. Various inputs, instructions, settings, etc., are input to the operation unit 74. The communication I / F 75 is a connection device for communicating with the transport device 1C.

[0049] <Drive Processing> Referring to Figure 4, the drive process will be explained. The drive process is performed by the CPU 61 of the conveying device 1C. The machining process starts when the CPU 61 reads and executes the drive program.

[0050] In the drive process, the transport device 1C controls the machine tools 1A and 1B. Then, according to the machining schedule, the workpiece is loaded and unloaded, and the machining operation is performed. Let's take the example of a machining schedule in which the machining operation is performed in the order of machine tools 1A, 1B, 1A, ...

[0051] The CPU 61 outputs an instruction signal to the machine tool 1A to open the shutter 32. The CPU 71 of the machine tool 1A detects the instruction signal and opens the shutter 32.

[0052] The CPU 61 controls the robot arm 40. The robot arm 40 holds the pallet P with the workpiece attached in the end effector 45 and removes the pallet P from the support base 52. The robot arm 40 passes its arm section 4A through the entrance / exit 56L of the transport device 1C and the entrance / exit 310 of the machine tool 1A. As a result, the pallet P is brought into the housing 30 of the machine tool 1A. The brought-in pallet P is fixed to the table 25B of the machine tool 1A.

[0053] After the pallet P is fixed to the table 25B, the robot arm 40 houses the arm section 4A, ball joint 44, and end effector 45 into the housing 50. This completes the loading of the workpiece into the machine tool 1A (T11).

[0054] The CPU 61 outputs an instruction signal to the machine tool 1A to close the shutter 32. The CPU 71 of the machine tool 1A detects the instruction signal and closes the shutter 32.

[0055] CPU 61 outputs an instruction signal to machine tool 1A to select the NC program with identification code "001" (T13). CPU 71 of machine tool 1A detects the instruction signal. CPU 71 of machine tool 1A reads the NC program with identification code "001" from memory 72.

[0056] CPU 61 outputs an instruction signal to machine tool 1A to mount the specified tool 29 onto the spindle 24 (T15). CPU 71 of machine tool 1A detects the instruction signal. CPU 71 of machine tool 1A drives the tool changer 26 to mount the specified tool 29 onto the spindle 24 (U11). After mounting the tool 29, CPU 71 of machine tool 1A outputs a notification signal to the transport device 1C to indicate that mounting is complete. CPU 61 detects the notification signal (T17).

[0057] The CPU 61 outputs a start signal to the machine tool 1A to initiate the machining operation (T19). The CPU 71 of the machine tool 1A detects the start signal. The CPU 71 of the machine tool 1A executes the machining operation based on the NC program read from memory 72 (U13). As a result, machining is performed on the workpiece mounted on the pallet P.

[0058] The CPU 71 of machine tool 1A outputs a notification signal to the transport device 1C to indicate the completion of the machining operation after the machining operation is finished. The CPU 61 detects the notification signal (T21).

[0059] The CPU 61 outputs an instruction signal to the machine tool 1A to open the shutter 32. The CPU 71 of the machine tool 1A detects the instruction signal and opens the shutter 32.

[0060] The CPU 61 controls the robot arm 40. The robot arm 40 passes its arm section 4A through the entrance / exit 56L of the transport device 1C and the entrance / exit 310 of the machine tool 1A. The robot arm 40 holds the pallet P, which is fixed to the table 25B of the machine tool 1A, with the end effector 45 and detaches it from the table 25B. The robot arm 40 houses the arm section 4A, the ball joint 44, and the end effector 45 into the housing 50. As a result, the pallet P is discharged from inside the housing 30 of the machine tool 1A.

[0061] The robot arm 40 places the pallet P, on which the processed workpiece is attached, onto the support base 52. This completes the removal of the workpiece from the machine tool 1A (T23).

[0062] The CPU 61 outputs an instruction signal to the machine tool 1A to close the shutter 32. The CPU 71 of the machine tool 1A detects the instruction signal and closes the shutter 32.

[0063] The processes T31-T43 in which CPU 61 causes machine tool 1B to execute machining operations correspond to the processes T11-T23 in which CPU 61 causes machine tool 1A to execute machining operations. The CPU 71 of machine tool 1B mounts the specified tool 29 onto the spindle 24 (U31). The CPU 71 of machine tool 1B executes machining operations based on the NC program with identification code "002" (U33).

[0064] The processes T51 to T63 in which the CPU 61 causes the machine tool 1A to execute a machining operation correspond to the processes T11 to T23 in which the CPU 61 causes the machine tool 1A to execute a machining operation. The CPU 71 of the machine tool 1A mounts the specified tool 29 onto the spindle 24 (U51). The CPU 71 of the machine tool 1A executes a machining operation based on the NC program with identification code "003" (U53).

[0065] However, the operation of the control system 1 based on the machining schedule is not limited to the above. For example, the timing of the machining operations of machine tools 1A and 1B may overlap. In this case, for example, after the loading of the workpiece into machine tool 1A is completed at T11, and before the unloading of the workpiece is completed at T27, the loading of the workpiece into machine tool 1A may occur at T31.

[0066] <Monitoring process> Referring to Figure 5, the monitoring process performed by the CPU 61 of the transport device 1C will be described. The monitoring process is executed in parallel with the drive process while the drive process is running. The monitoring process is started when the CPU 61 reads and executes the monitoring program.

[0067] CPU 61 outputs a request signal to machine tools 1A and 1B, respectively, to request a status. The CPU 71 in machine tools 1A and 1B detects the request signal. The CPU 71 in machine tools 1A and 1B then identifies the following status. (1) Whether or not an abnormality occurred (2) Opening and closing state of shutter 32

[0068] Furthermore, (1) whether or not an abnormality has occurred includes whether or not the following abnormalities have occurred. (a) Any abnormality that occurs during a machining operation and is caused by the machining operation. (b) Reset stop abnormality in which an operation to stop the machining operation and reset is performed on the operating unit 74 (c) An emergency stop malfunction occurred when an operation to stop machine tools 1A and 1B was performed on the operating section 74 of machine tools 1A and 1B.

[0069] Machining abnormalities include motor abnormalities occurring in the motor assemblies 76 of machine tools 1A and 1B. Machining abnormalities also include clamp abnormalities occurring in the mechanism that secures the pallet P to the three pallet clamps 250 of table 25B.

[0070] The CPUs 71 of machine tools 1A and 1B each output a notification signal to the transport device 1C indicating the specified state.

[0071] The CPU 61 detects notification signals output from machine tools 1A and 1B. Based on the detected notification signals, the CPU 61 detects the respective states of machine tools 1A and 1B (S11).

[0072] Based on the status of machine tool 1A detected in S11, CPU 61 determines whether an abnormality has occurred in machine tool 1A (S13). If CPU 61 determines that no abnormality has occurred (S13: NO), it proceeds to S23.

[0073] If the CPU 61 determines that an abnormality has occurred in machine tool 1A (S13: YES), it proceeds to S15. The CPU 61 determines that the type of abnormality is (a) an emergency stop abnormality (S15). If the CPU 61 determines that it is an emergency stop abnormality (S15: YES), it proceeds to S35. The CPU 61 stops the drive processing for machine tools 1A and 1B (S35). The CPU 61 terminates the monitoring process.

[0074] When the drive process for machine tools 1A and 1B is completed, the output of various signals from the transport device 1C to machine tools 1A and 1B is stopped. Also, the loading and unloading of workpieces between machine tools 1A and 1B and the transport device 1C is stopped. As a result, the drive of machine tools 1A and 1B is stopped. For example, if machining operations are currently being performed on machine tools 1A and 1B, the drive of machine tools 1A and 1B will be stopped after the completion of the ongoing machining operations.

[0075] If CPU 61 determines that the type of abnormality is not an emergency stop abnormality (S15: NO), it proceeds to S17. In this case, (b) a machining abnormality or (c) a reset stop abnormality has occurred in machine tool 1A.

[0076] Based on the state of the machine tool 1A detected in S11, the CPU 61 determines whether the shutter 32 of the machine tool 1A is closed (S17). If the CPU 61 determines that the shutter 32 of the machine tool 1A is open (S17: NO), the process proceeds to S35. The CPU 61 stops the drive processing for machine tools 1A and 1B (S35). The CPU 61 terminates the monitoring process.

[0077] If the CPU 61 determines that the shutter 32 of the machine tool 1A is closed (S17: YES), it proceeds to S19. The CPU 61 stops the drive process for the machine tool 1A (S19). On the other hand, the CPU 61 continues the drive process for the machine tool 1B (S19). The CPU 61 then proceeds to S23.

[0078] When the drive process for machine tool 1A is completed, the drive of machine tool 1A is stopped. On the other hand, the drive process for machine tool 1B is not terminated. Therefore, the output of various signals from the transport device 1C to machine tool 1B, and the loading and unloading of workpieces between machine tool 1B and the transport device 1C are not stopped. As a result, machining operations based on the machining schedule continue in machine tool 1B.

[0079] In S23-S29, the same processing as in S11-S17 is performed. In S21-S27, machine tool 1A, which was the subject of the decision in S13-S19, is changed to machine tool 1B.

[0080] If the CPU 61 determines that an emergency stop abnormality has occurred in machine tool 1B (S25: YES), it proceeds to S35. If the CPU 61 determines that the shutter 32 of machine tool 1B is open (S27: NO), it proceeds to S35. The CPU 61 stops the drive processing for machine tools 1A and 1B (S35).

[0081] If the CPU 61 determines that the shutter 32 of the machine tool 1B is closed (S27: YES), it stops the drive process for the machine tool 1B (S29). On the other hand, the CPU 61 continues the drive process for the machine tool 1A (S29). The CPU 61 then proceeds to S31.

[0082] The CPU 61 determines whether an emergency stop operation for the transport device 1C has been performed on the control unit 57B of the transport device 1C (S31). If the CPU 61 determines that an emergency stop operation has been performed (S31: YES), it proceeds to S35. The CPU 61 stops the drive processing for the machine tools 1A and 1B (S35). The CPU 61 terminates the monitoring process.

[0083] If the CPU 61 determines that no emergency stop operation has been performed (S31: NO), it proceeds to S33. The CPU 61 determines that the drive processes for both machine tools 1A and 1B have stopped (S33). If the CPU 61 determines that the drive process for at least one of machine tools 1A and 1B has not stopped (S33: NO), it returns to S11.

[0084] If CPU 61 determines that the drive processes for both machine tools 1A and 1B have stopped (S33: YES), it terminates the monitoring process.

[0085] <Operation and effects of this embodiment> Any abnormalities occurring in machine tools 1A and 1B with the shutter 32 open may be caused by the transport device 1C during workpiece loading and unloading. For example, if the transport device 1C fails to position the pallet P and cannot secure the pallet P to the pallet clamp 250 on the table 25B, a clamping abnormality may occur in machine tools 1A and 1B. Also, if the end effector 45 of the transport device 1C comes into contact with the table 25B, a motor abnormality may occur in machine tools 1A and 1B. Furthermore, if the arm portion 4A of the transport device 1C is inserted into machine tools 1A and 1B while machining is in progress, the user may operate the control unit 74 to trigger a reset stop abnormality.

[0086] If an abnormality is detected in the open machine tool 1A, and the transport device 1C is driven to allow the machining operation to continue in the machine tool 1B, there is a possibility that the machine tools 1A, 1B, and the transport device 1C may malfunction. This malfunction may occur, for example, when the arm portion 4A comes into contact with the main body 20 or housing 30 of the machine tools 1A and 1B due to a malfunction of the transport device 1C.

[0087] In contrast, in the control system 1, if the shutter 32 of machine tool 1A, where an abnormality has been detected, is open (S17: NO), the drive processing for both machine tools 1A and 1B is stopped (S35). The same applies if an abnormality is detected in machine tool 1B (S27: NO → S35).

[0088] This allows the control system 1 to reduce the possibility of failure of the machine tools 1A and 1B and the conveying device 1C.

[0089] On the other hand, in the control system 1, if the shutter 32 of the machine tool 1A where an abnormality has been detected is in the closed state (S17: YES), the drive process of the machine tool 1B is continued (S19). This allows the control system 1 to continue the machining schedule as much as possible.

[0090] The abnormalities detected by machine tools 1A and 1B include machining abnormalities that occur during machining operations. When a machining abnormality occurs in machine tools 1A and 1B, the control system 1 can control machine tools 1A and 1B according to the state of the shutter 32.

[0091] The abnormalities detected in machine tools 1A and 1B include reset stop abnormalities that stop the machining operation and reset the machine. When a reset stop abnormality occurs in machine tools 1A or 1B, the control system 1 can control machine tools 1A and 1B according to the state of the shutter 32.

[0092] If an operation is performed to emergency stop a machine tool 1A, 1B, or a conveying device 1C, it is highly likely that it will be difficult to continue the machining schedule. In contrast, in the control system 1, if an operation is performed to emergency stop a conveying device 1C, or machine tools 1A, 1B, the drive processing for machine tools 1A, 1B is stopped regardless of the state of the shutter 32 (S35). As a result, the control system 1 can quickly stop the machining schedule when it is necessary to emergency stop a conveying device 1C, or machine tools 1A, 1B.

[0093] <Variation> The present invention is not limited to the above embodiments, and various modifications are possible. In the control system 1, the number of machine tools is not limited to two, but may be three or more. If there are three or more machine tools, the drive processing for all machine tools is stopped in S35 of the monitoring process.

[0094] The mechanism by which the transport device 1C loads and unloads workpieces into and out of machine tools 1A and 1B is not limited to the robot arm 40, but may be any other mechanism.

[0095] The drive and monitoring processes do not need to be performed by the CPU 61 of the transport device 1C. For example, the control system 1 may include a control device that controls the machine tools 1A and 1B to perform machining operations according to a machining schedule. The control device may be a PC, for example.

[0096] The abnormalities identified by machine tools 1A and 1B are not limited to (a) machining abnormalities, (b) reset stop abnormalities, or (c) emergency stop abnormalities. For example, machine tools 1A and 1B may identify tool change abnormalities that occur when changing tools, opening / closing abnormalities that occur when opening and closing the shutter 32, or communication error abnormalities that result in failure of communication with the conveying device 1C.

[0097] If an emergency stop malfunction occurs in machine tools 1A or 1B, the transport device 1C may output an emergency stop signal to machine tools 1A or 1B. If machine tools 1A or 1B are in the middle of a machining operation when they detect the emergency stop signal, they may stop the machining operation.

[0098] In the monitoring process, the S31 process does not need to be executed.

[0099] <Other> T11 to T63 are examples of the "driving process" and "driving steps" of the present invention. The process in S11 is an example of the "detection process" and "detection steps" of the present invention. The processes in S13 and S23 are examples of the "first decision process" and "first decision steps" of the present invention. The process in S35 is an example of the "first control process" and "first control steps" of the present invention. The processes in S19 and S29 are examples of the "second control process" and "second control steps" of the present invention. The processes in S15, S25, and S33 are examples of the "second decision process" of the present invention. [Explanation of Symbols]

[0100] 1: Control System 1A, 1B: Machine tools 1C: Conveyor device 32: Shutter 61: CPU 74:Operation section 310: Loading / unloading entrance

Claims

1. A control system for controlling a plurality of machine tools that perform processing on workpieces brought in through an entrance / exit with a shutter for opening and closing an entrance / exit for loading and unloading workpieces, and a conveying device for loading and unloading workpieces to and from the plurality of machine tools, A drive process that, according to a predetermined processing schedule, loads and unloads the workpieces from the transport device to the plurality of machine tools, A detection process for detecting an abnormality that has occurred in any of the aforementioned machine tools, A first determination process for determining the open / closed state of the shutter in a machine tool in which the abnormality was detected by the above detection process, In the first determination process, if it is determined that the shutter is in the open state, a first control process is performed to stop the drive process for the plurality of machine tools, In the first determination process, if it is determined that the shutter is in a closed state, a second control process is performed to stop the drive process for one machine tool and continue the drive process for the other machine tool. A control system characterized by performing the following.

2. The aforementioned detection process is: The control system according to claim 1, characterized in that it detects a machining abnormality that occurs during the machining of the workpiece in any of the aforementioned plurality of machine tools as the abnormality.

3. The aforementioned detection process is: The control system according to claim 1, characterized in that it detects a reset stop that stops the machining of the workpiece by the machine tool as an abnormality.

4. A second determination process for determining whether an operation to emergency stop the transport device or the machine tool has been performed, If the second decision process determines that the operation has been performed, a third control process is performed to stop the drive process for the plurality of machine tools, regardless of the result of the first decision process. The control system according to claim 1, further characterized by performing the following:

5. A control method for controlling a plurality of machine tools that perform processing on workpieces brought in through an entrance / exit with a shutter for opening and closing an entrance / exit for loading and unloading workpieces, and a conveying device that loads and unloads the workpieces to and from the plurality of machine tools, A drive process in which the workpiece is loaded and unloaded by the conveying device to the plurality of machine tools according to a predetermined processing schedule, A detection step for detecting an abnormality that has occurred in any of the aforementioned multiple machine tools, A first determination step of determining the open / closed state of the shutter in a machine tool in which the abnormality was detected by the above detection step, In the first determination step, if it is determined that the shutter is in the open state, a first control step is performed to stop the drive process for the plurality of machine tools, In the first determination step, if it is determined that the shutter is in a closed state, the second control step stops the drive process for one machine tool and continues the drive process for the other machine tool. A control method characterized by comprising:

6. A computer controls a plurality of machine tools that perform processing on the workpieces brought in through the loading / unloading entrances, which are equipped with shutters for opening and closing loading / unloading entrances for loading and unloading workpieces, and a transport device that loads and unloads the workpieces to and from the plurality of machine tools, A drive process that, according to a predetermined processing schedule, loads and unloads the workpieces from the transport device to the plurality of machine tools, A detection process for detecting an abnormality that has occurred in any of the aforementioned machine tools, A first determination process for determining the open / closed state of the shutter in a machine tool in which the abnormality was detected by the above detection process, In the first determination process, if it is determined that the shutter is in the open state, a first control process is performed to stop the drive process for the plurality of machine tools, In the first determination process, if it is determined that the shutter is in a closed state, a second control process is performed to stop the drive process for one machine tool and continue the drive process for the other machine tool. A control program to execute the program.

7. A conveying device that includes a shutter for opening and closing an entrance for loading and unloading workpieces, and for loading and unloading workpieces into and out of a plurality of machine tools that process the workpieces loaded through the entrance, A drive process that loads and unloads the workpiece to and from the multiple machine tools according to a predetermined processing schedule, A detection process for detecting an abnormality that has occurred in any of the aforementioned machine tools, A first determination process for determining the open / closed state of the shutter in a machine tool in which the abnormality was detected by the above detection process, In the first determination process, if it is determined that the shutter is in the open state, a first control process is performed to stop the drive process for the plurality of machine tools, In the first determination process, if it is determined that the shutter is in a closed state, a second control process is performed to stop the drive process for one machine tool and continue the drive process for the other machine tool. A transport device characterized by performing the following actions.

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