Control system, control method, program, and conveyance device

Abstract

Provided are a control system, a control method, a program, and a conveyance device that are each capable of suppressing a decrease in productivity. A control unit of a control system according to the present invention includes a control unit for performing a processing step multiple times. In the processing step, a workpiece is loaded into a machine tool with a conveyance device, the workpiece which has been loaded into is processed with the machine tool, and the processed workpiece is unloaded from the machine tool with the conveyance device. The control unit determines the presence or absence of an abnormality for each processing step (S101, S105). The control unit determines to skip a processing step which has been determined to have an abnormality (S125). The control unit determines to perform a processing step that is later than the processing step which has been determined to be skipped and that has been determined to have no abnormality (S107).

Description

Control System, Control Method, Program, and Transfer Device

[0001] The present invention relates to a control system, a control method, a program, and a transfer device.

[0002] The machine tool system of Patent Document 1 includes a loader device and a processing unit. The loader device transports a workpiece to the processing unit. The processing unit processes the workpiece transported by the loader device with a tool. The processed workpiece is carried out of the processing unit by the loader device. When it is determined that, for example, the tool has reached its lifespan, the machine tool system stops the loading of the workpiece into the processing unit by the loader device.

[0003] International Publication No. 2023 / 047857

[0004] In the above machine tool system, when an abnormality such as the tool reaching its lifespan occurs, for example, the next workpiece is not loaded into the processing unit, so the subsequent workpiece processing steps are not executed and productivity decreases.

[0005] An object of the present invention is to provide a control system, a control method, a program, and a transfer device that can suppress a decrease in productivity.

[0006] In a control system including a control unit that repeatedly executes a processing step of loading a workpiece into a machine tool by a transfer device, processing the loaded workpiece in the machine tool, and unloading the processed workpiece from the machine tool by the transfer device, the control unit executes a first determination process for determining the presence or absence of an abnormality for each processing step, a first determination process for determining to skip the processing step determined to have the abnormality in the first determination process, and a second determination process for determining to execute the processing step after the processing step determined to be skipped in the first determination process and determined to have no abnormality in the first determination process.

[0007] The above control system skips a processing step determined to have an abnormality and executes a processing step without an abnormality. Since there is no need to stop the machine tool, the control system can suppress a decrease in productivity.

[0008] In the present invention, the control system may determine that there is an abnormality in the machining process if there is an abnormality in the NC program executed for each machining process. The control system cannot properly machine the workpiece if there is an abnormality in the NC program of the machining process. The control system can suppress the decrease in productivity by skipping the machining process in which there is an abnormality in the NC program.

[0009] In the present invention, the control system may determine in the first decision process that there is an abnormality in the machining process if the workpiece, which has been transported to the machine tool by the transport device, is not clamped to the table of the machine tool. The control system cannot properly machine the workpiece if it is not clamped to the table. The control system can suppress a decrease in productivity by skipping the machining process in which there is an abnormality in the clamping.

[0010] In the present invention, the control system may be characterized in that the machine tool is equipped with a detection unit that detects whether the workpiece is clamped to the table, and the first decision process determines whether or not there is an abnormality based on the detection result of the detection unit. The control system can accurately detect clamping abnormalities by checking the detection result of the detection unit.

[0011] In the present invention, the control system further includes maintenance of the machine tool in the machining process, and the control unit may perform, for each machining process, a second decision process to determine whether or not there is an abnormality in the maintenance program for performing the maintenance; a third decision process to decide to skip only the maintenance among the machining processes if the second decision process determines that there is an abnormality in the maintenance program; and a fourth decision process to decide to execute the machining process after the machining process that was skipped in the third decision process, which the first decision process determined to be free of abnormalities. If there is an abnormality in the maintenance program, the control system will skip only the maintenance among the machining processes and perform the machining. Even if the maintenance is not performed, the control system will execute the next machining process without stopping the machine tool. Therefore, the control system can suppress a decrease in productivity.

[0012] In the present invention, the control system may include a setting process which sets the execution of the first decision process to be enabled or disabled, and a fifth decision process which determines to stop the machine tool if the execution of the first decision process is disabled in the setting process and the first judgment process determines that there is an abnormality in the machining process. The user can choose to skip the abnormal machining process and continue with the machining processes without abnormalities, or to stop the machine tool, if there is an abnormality in the machining process.

[0013] In the present invention, the control system may perform the first decision process before the conveying device loads the workpiece into the machine tool. The control system can prevent the conveying device from loading the workpiece into the machine tool if there is an abnormality in the machining process and machining is not possible.

[0014] In the present invention, the control unit of the control system may perform a notification process to notify the existence of the machining process that was decided to be skipped in the first decision process. The user can then recognize the existence of the skipped machining process.

[0015] A control method according to a second aspect of the present invention is a control method for a control system that performs a processing step of transporting a workpiece into a machine tool by a transport device, processing the transported workpiece in the machine tool, and transporting the processed workpiece out of the machine tool by the transport device, multiple times, characterized in that it performs a first determination step of determining whether or not there is an abnormality in each of the processing steps; a first decision step of deciding to skip the processing step for which an abnormality was determined in the first determination step; and a second decision step of deciding to execute the processing step after the processing step for which it was decided to skip in the first decision step, for which no abnormality was determined in the first determination step. The above control method obtains the same effects as the control system according to the first aspect.

[0016] A third aspect of the present invention provides a control system computer that performs a machining process multiple times, in which a workpiece is transported to a machine tool by a transport device, the transported workpiece is machined in the machine tool, and the machined workpiece is transported out of the machine tool by the transport device. The computer computer is configured to function as a first determination unit that determines whether or not there is an abnormality in each machining process, a first decision unit that decides to skip the machining process in which the first determination unit determines there is an abnormality, and a second decision unit that decides to execute the machining process after the machining process that the first decision unit decided to skip, in which the first determination unit determines there is no abnormality. The above program achieves the same effects as the control system of the first aspect.

[0017] A transport device according to a fourth aspect of the present invention is a transport device comprising a control unit that executes a processing step of transporting a workpiece into a machine tool, processing the transported workpiece in the machine tool, and transporting the processed workpiece out of the machine tool multiple times, wherein the control unit executes a first determination process that determines whether or not there is an abnormality in each of the processing steps, a first decision process that decides to skip the processing step for which the first determination process determines there is an abnormality, and a second decision process that decides to execute the processing step after the processing step for which the first decision process decided to skip, for which the first determination process determined there is no abnormality. The transport device obtains the same effects as the control system according to the first aspect.

[0018] This is a perspective view showing the control system 1. This is a perspective view showing the conveying device 1C. This is a diagram showing the electrical configuration of the machine tools 1A and 1B and the conveying device 1C. This is a diagram showing the machining schedule executed by the control system 1. This is a diagram showing the machining process. This is a diagram showing the main process. This is a diagram showing the machining process. This is a diagram showing the machining process, a continuation of Figure 7. This is a diagram showing the execution result of the machining schedule. This is a diagram showing the machining history screen. This is a diagram showing the status screen.

[0019] A control system 1 according to one embodiment of the present invention will be described. The referenced drawings are used to illustrate the technical features that the present invention may adopt. The configurations, controls, etc., shown in the drawings are not intended to be the sole limiting factors, but are merely illustrative examples. In the following description, the left / right, front / back, and up / down directions indicated by arrows in the drawings will be used. The left / right direction, up / down direction, and front / back direction are the X-axis direction, Z-axis direction, and Y-axis direction of the machine tools 1A and 1B, respectively.

[0020] <Overview of Control System 1> As shown in Figure 1, the control system 1 includes machine tools 1A and 1B, and a transport device 1C. Machine tools 1A and 1B perform various machining operations on workpieces. The operations in which machine tools 1A and 1B perform various machining operations on workpieces are called "machining operations". The transport device 1C handles the loading and unloading of workpieces to and from machine tools 1A and 1B.

[0021] Machine tool 1A is located to the left of conveying device 1C. Machine tool 1B is located to the right of conveying device 1C. Machine tools 1A, 1B, and conveying device 1C are arranged in a left-to-right direction.

[0022] The machine tool 1A has a main body 20 and a housing 30.

[0023] The main body 20 comprises 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 roughly rectangular metal base. The column 22 is fixed to the upper rear of the base 21. The Z-axis movement mechanism is positioned in front 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.

[0024] The spindle 24 is located inside the spindle head 23. The spindle 24 has a mounting hole at its lower end. The spindle 24 rotates in response to the drive of the spindle motor, with a tool holder mounted in the mounting hole. The tool holder holds the tool 29.

[0025] The table device 25 includes a Y-axis movement mechanism, a Y-axis table 25A, a table 25B, an X-axis movement mechanism, and the like. The Y-axis movement mechanism is positioned on the upper surface of the base 21. The Y-axis movement mechanism moves the Y-axis table 25A in the Y-axis direction in response to the drive of the Y-axis motor.

[0026] The X-axis movement mechanism is positioned on the upper surface of the Y-axis table 25A. The X-axis movement mechanism moves the table 25B in the X-axis direction in response to the drive of the X-axis motor. Therefore, the table 25B can move in both the X-axis and Y-axis directions on the base 21 by the X-axis movement mechanism and the Y-axis movement mechanism.

[0027] Three pallet clamps 250 are fixed to the table 25B. The pallet clamps 250 secure the pallet P shown in Figure 2 to the table 25B. With the pallet P placed on the table 25B, the three pallet clamps 250 are inserted into the three holes on the bottom surface of the pallet P.

[0028] The tool changer 26 is located in front 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 circle on its outer circumference. The grip arms 260 grip the tool holder. The tool changer 26 has a magazine motor at its top. The magazine motor rotates the tool magazine 26A.

[0029] The control box 27 is fixed to the rear of the column 22 and houses the numerical control device 10 shown in Figure 3. The numerical control device 10 controls the Z-axis motor, spindle motor, X-axis motor, Y-axis motor, magazine motor, and the opening / closing motor described later. The numerical control device 10 performs various machining operations on the workpiece by moving the workpiece attached to the pallet P held on the table 25B and the tool 29 attached to the spindle 24 relative to each other. These various machining operations include drilling using drills and taps, and side machining using end mills and milling cutters.

[0030] The housing 30 prevents chips generated during machining by the machine tool 1A and the scattering of cleaning fluid from the machine tool 1A. The housing 30 has a cover 31 and a shutter 32.

[0031] 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 transport device 1C. Wall 31N is the right wall of the cover 31. A shutter 32 is provided on wall 31N. The shutter 32 moves vertically by an opening / closing motor. By moving vertically, the shutter 32 can open and close the entrance / exit 310.

[0032] 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".

[0033] 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.

[0034] As shown in Figure 2, the transport device 1C has a robot arm 40 and a housing 50.

[0035] 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, a plurality of links 43, a ball joint 44, and an end effector 45 are referred to as the "arm section 4A".

[0036] 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 multiple rotary joints 42 rotates, the multiple links 43 move freely. End effectors 45 are connected to the ends of the multiple links 43 via ball joints 44. The end effectors 45 can be fitted with a detachable pallet P.

[0037] The housing 50 has a cover 51 and a support base 52.

[0038] The cover 51 has a box shape and surrounds the robot arm 40. An entrance / exit 56L is formed in the left wall 51L of the cover 51. An entrance / exit 56R is formed in the right wall 51R of the cover 51.

[0039] An operation panel 57 is positioned on the front of the front wall 51F of the cover 51. The operation panel 57 includes a display unit 57A and an operation unit 57B. Various screens are displayed on the display unit 57A. Various inputs, instructions, settings, etc., are input to the operation unit 57B.

[0040] 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.

[0041] 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 pallets P, while placed on the front support base 52F and the rear support base 52B, are housed inside the cover 51. The front support base 52F functions as a front stocker for the pallets P. The rear support base 52B functions as a rear stocker for the pallets P.

[0042] <Electrical Configuration> Referring to FIG. 3, the electrical configurations of the transfer device 1C and the machine tools 1A and 1B will be described.

[0043] The transfer device 1C includes a control unit 60, a display unit 57A, an operation unit 57B, communication I / Fs 63 and 64, and a motor assembly 40A. The motor assembly 40A includes various motors that drive the base 41, the rotary joint 42, the ball joint 44, and the end effector 45 of the robot arm 40. Hereinafter, the interface will be denoted as "I / F".

[0044] The control unit 60, the display unit 57A, the operation unit 57B, the communication I / Fs 63 and 64, and the motor assembly 40A are electrically connected.

[0045] The control unit 60 includes a CPU 61 and a memory 62. The CPU 61 performs overall control of the transfer device 1C. The memory 62 stores a processing program, set values, various parameters, etc. for the CPU 61 to execute processing. The processing program is a program for causing the machine tools 1A and 1B to sequentially execute machining operations according to a predetermined machining schedule.

[0046] The communication I / F 63 is a connection device for communicating with the machine tool 1A. The communication I / F 64 is a connection device for communicating with the machine tool 1B.

[0047] Each numerical control device 10 of the machine tools 1A and 1B includes a control unit 70, a display unit 73, an operation unit 74, a communication I / F 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.

[0048] The control unit 70, the display unit 73, the operation unit 74, the communication I / F 75, the motor assembly 76, and the sensor 77 are electrically connected.

[0049] 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 NC programs, cleaning programs, set values, various parameters, etc. The NC program describes the machining operations of the machine tools 1A and 1B using multiple control commands in a predetermined programming language. The cleaning program describes the cleaning operations inside the housing 30 performed by the machine tools 1A and 1B.

[0050] The display unit 73 is a device that displays various screens. Various inputs, instructions, settings, etc., are input to the operation unit 74. The communication interface 75 is a connection device for communicating with the transport device 1C.

[0051] Sensor 77 detects whether the pallet P is clamped to the table 25B. For example, sensor 77 detects air pressure. If the clamping is done correctly, the air pressure will be high, and if there is a problem with the clamping, the air pressure will be low.

[0052] Referring to Figure 4, the machining schedule will be explained. The schedule is set by the operator's operation of the control unit 57B. According to the machining schedule set by the operator, the transport device 1C causes the machine tools 1A and 1B to perform machining on the workpiece.

[0053] The machining schedule for machine tools 1A and 1B consists of, for example, multiple machining processes B1 to B5. The scheduled machining processes B1 to B5 are executed sequentially. In each machining process B1 to B5, the machining process specified by the operator is executed. In other words, within a single machining schedule, the control unit 60 executes the machining processes multiple times.

[0054] In machining processes B1 to B5, the workpiece is machined using machine tool 1A. In machining processes B1 to B5, the workpiece is machined using machine tool 1B.

[0055] In each schedule, machining processes B1 to B5 may execute the same NC program, or different NC programs may be executed.

[0056] Referring to Figure 5, the machining processes ST1 to ST6 will be described. Machining processes ST1 to ST5 are executed by commands from the control unit 60. In machining process ST1, machine tool 1A or machine tool 1B identifies an NC program based on the commands from the control unit 60. In machining process ST2, based on the commands from the control unit 60, the robot arm 40 loads the workpiece into machine tool 1A or machine tool 1B.

[0057] In machining process ST3, machine tool 1A or machine tool 1B executes an NC program to machine the workpiece on the pallet P that has been brought in.

[0058] In machining process ST4, the robot arm 40 removes the machined workpiece from the machine tool 1A based on a command from the control unit 60.

[0059] In machining step ST5, the machine tool 1A or machine tool 1B identifies a cleaning program based on a command from the control unit 60. In machining step ST6, the machine tools 1A and 1B execute the identified cleaning program to clean the inside of machine tool 1A.

[0060] <Main Processing> The main processing will be explained with reference to Figure 6. The main processing is performed by the control unit 60 of the transport device 1C. The operator turns on the power to the transport device 1C and the machine tools 1A and 1B. When the power is turned on, the control unit 60 of the transport device 1C reads and executes the processing program. After executing the processing program, the control unit 60 performs the main processing.

[0061] The control unit 60 determines whether it has received the workpiece processing schedule (S1). The operator operates the operation unit 57B to create the workpiece processing schedule. The processing schedule created by the operator is then executed.

[0062] If the control unit 60 determines that it has not received a processing schedule (S1: NO), it returns the process to S1. If it determines that it has received a processing schedule (S1: YES), the control unit 60 executes the process to set a skip for the processing steps (S3). Skipping a processing step means that if an abnormality is detected in the process of S101 or S105 described later, the corresponding processing step is not executed, and the next processing step is executed instead.

[0063] The control unit 60 transmits machining schedule information to the machine tools 1A and 1B (S5). The machining schedule information includes NC program and cleaning program information for each machining process.

[0064] The control unit 60 executes the machining process (S7). The control unit 60 executes the machining process targeting machine tool 1A. Independently, the control unit 60 executes the machining process targeting machine tool 1B. For the sake of clarity, the machining process targeting machine tool 1A will be described in detail below.

[0065] When a machining process is executed, the control unit 60 determines whether there is an abnormality in the NC program used in the target machining process (S101). The control unit 60 causes the machine tool 1A to analyze for abnormalities in the NC program executed, for example, in machining process B1. When the analysis is completed, the machine tool 1A transmits the analysis results of the NC program to the transport device 1C. The control unit 60 receives the analysis results from the machine tool 1A and determines whether there is an abnormality in the NC program.

[0066] This section explains NC program abnormalities. NC program abnormalities include tool abnormality errors, program errors, program selection abnormalities, etc.

[0067] Tool malfunction errors include, for example, tool count overload, T-code range error, no tool in magazine, and end of tool life.

[0068] Tool count overload refers to a situation where, for example, the number of tools 29 used in the NC program is greater than the number of tools 29 loaded in the tool magazine 26A. T-code range error refers to a situation where the range of the T-code in the NC program is specified outside the normal range. No tool 29 in tool magazine 26A refers to a situation where the tool 29 specified in the NC program is not loaded in the tool magazine 26A. End of tool life refers to a determination that the tool 29 has reached the end of its lifespan based on its usage time in the machine tool 1A.

[0069] Program errors include, for example, the absence of an NC program, the inability to issue interrupt-type macro commands, subprogram number errors, unset G-code macro programs, and exceeding the number of operating subprograms.

[0070] "No NC program" means, for example, that the NC program specified in the machining process of the machining schedule is not stored in the machine tool 1A. "Interrupt-type macro command unavailable" means that the macro command that interrupts the execution of the NC program cannot be executed.

[0071] A subprogram number error means that there is no subprogram corresponding to the number. A G-code macro program not set means that the G-code macro program has not been set. An over-operation subprogram count means that the number of subprograms required for the machining process is insufficient on the machine tool 1A side.

[0072] Program selection errors include external program selection number errors and external program selection folder name errors. An external program selection number error occurs, for example, when there is no external program with the specified number for machine tool 1A. An external program selection folder name error occurs when there is no folder with the specified name.

[0073] The machine tool 1A checks each of these items one by one and sends the check results to the pallet P transport device 1C. The machine tool 1A may send the check results to the transport device 1C all at once, or it may send the check results each time it checks an item.

[0074] If the control unit determines that there is no abnormality in the NC program (S101: NO), the control unit 60 executes the unloading process (S103). In the unloading process, the control unit 60 controls the robot arm 40, the unloading entrance 56R, and the shutter 32 of the machine tool 1A to unload the symmetrical pallet P from the transport device 1C to the machine tool 1A.

[0075] Once the unloading to machine tool 1A is complete, the unloaded pallet P is clamped to the table 25B of machine tool 1A.

[0076] The control unit 60 determines whether or not there was an abnormality in the clamping of the pallet P to the table 25B (S105). The control unit 60 requests the status of the clamp from the machine tool 1A.

[0077] The machine tool 1A detects the air pressure from the sensor 77 and determines if there is a clamping abnormality. If the air pressure is higher than the threshold, it indicates that the clamping was performed correctly. If the air pressure from the sensor 77 is lower than the threshold, it indicates that there is a clamping abnormality. The machine tool 1A notifies the conveying device 1C of the result.

[0078] If it is determined that there is no abnormality in the clamping of pallet P to table 25B (S105: NO), the machining of the workpiece on pallet P is performed based on the target machining process (S107).

[0079] The control unit 60 determines whether or not the workpiece processing is complete (S109). For example, if the processing is complete, the machine tool 1A notifies the transfer device 1C that the processing is complete. The control unit 60 determines whether or not a notification has been made and determines that the workpiece processing is complete.

[0080] If the control unit determines that the workpiece processing is not complete (S109: NO), that is, if it has not received notification from the machine tool 1A, the control unit 60 returns to the previous state and waits.

[0081] When the control unit 60 determines that the workpiece processing is complete (S109: YES), that is, when it receives notification from the machine tool 1A, it executes the loading process (S111).

[0082] During the loading process, the control unit 60 sends a command to the machine tool 1A to open the shutter 32 of the machine tool 1A. The machine tool 1A opens the shutter 32. At the same time, the control unit 60 sends a command to the machine tool 1A to release the clamp on the table 25B of the pallet P. The machine tool 1A releases the clamp on the table 25B of the pallet P.

[0083] At the command of the control unit 60, the robot arm 40 transports the processed pallet P to the transport device 1C. The robot arm 40 places the pallet P back to its original position, i.e., the position before the processing step was performed. The control unit 60 sends a command to the machine tool 1A to close the shutter 32 of the machine tool 1A. The machine tool 1A closes the shutter 32.

[0084] The control unit 60 determines whether there is an abnormality in the cleaning program in the symmetrical machining process (S113). The control unit 60 instructs the machine tool 1A to check for abnormalities in the cleaning program. If the machine tool 1A has, for example, the target cleaning program stored, it determines that there is no abnormality in the cleaning program. If the machine tool 1A does not have, for example, the target cleaning program stored, it determines that there is an abnormality. The machine tool 1A notifies the transport device 1C of the confirmation result.

[0085] If the control unit 60 determines that there is no abnormality in the cleaning program (S113: NO), it instructs the machine tool 1A to perform internal cleaning (S114). The machine tool 1A starts the cleaning program and performs cleaning. The control unit 60 proceeds to S117.

[0086] On the other hand, if the control unit 60 determines that there is an abnormality in the cleaning program (S113: YES), it skips the execution of the cleaning program for the relevant processing step (S115). The control unit 60 proceeds to S117 without stopping the machine.

[0087] The following describes what happens when an abnormality is detected in S101 and S105. If an abnormality is detected in the NC program during the process in S105 (S105: YES), the control unit 60 determines whether or not to set a skip for the machining process (S119).

[0088] If the control unit 60 determines that there is no setting to skip a machining process (S119: NO), it stops the machine tool 1A (S121). The control unit 60 notifies that the machine has stopped (S123). The control unit 60 returns to the main process S1. In this case, the operator recognizes the abnormality in the NC program and takes actions such as changing the machining schedule or checking the NC program of the machine tool 1A.

[0089] On the other hand, if the control unit 60 determines that there is no setting for skipping a processing step (S119: YES), it decides to skip the processing step (S125). In other words, the control unit 60 proceeds with processing without executing the processing step and without stopping the machine. The control unit 60 notifies the user that the processing step has been skipped (S127). The user can recognize that the processing step has been skipped. The control unit 60 proceeds to S117.

[0090] If the control unit determines that there is an abnormality in the clamping of the pallet P to the table 25B (S105: YES), the control unit 60 determines whether or not to set a skip for the machining process (S129).

[0091] If the control unit 60 determines that there is no setting to skip a machining process (S129: NO), it stops the machine tool 1A (S131). The control unit 60 notifies the user (S133). The user can recognize that there was an abnormality in the clamp. The control unit 60 returns to the main process S1.

[0092] On the other hand, if it determines that there is a setting to skip a processing step (S129: YES), the control unit 60 decides to skip the processing step (S135). The control unit 60 notifies the user (S137). The user can recognize that the processing step has been skipped. The control unit 60 executes the loading process in the same way as the process in S111 (S139). The control unit 60 proceeds to process S117.

[0093] The control unit 60 executes the process of loading the pallet P from the machine tool 1A to the transport device 1C (S111). In other words, the control unit 60 loads the pallet P from the machine tool 1A to the transport device 1C without having the machine tool 1A process the workpiece.

[0094] The control unit 60 determines whether all processing schedules have been completed (S117). If it determines that the processing schedules have not been completed (S117: NO), the control unit 60 returns to process S101 and executes the next target processing step.

[0095] On the other hand, if the control unit 60 determines that the processing schedule is complete (S117: YES), it returns the processing to the main process.

[0096] For example, as shown in Figure 9, a machining schedule is set up for machining processes B1 to B5. In this case, machining processes B1, B2, and B3 are executed normally. On the other hand, machining processes B3 and B5 are skipped. In machining process B3, for example, an abnormality occurs in the NC program (S101: YES), and the machining process is skipped (S125). In machining process B3, for example, an abnormality occurs in the clamp (S105: YES), and the machining process is skipped (S135).

[0097] When processing returns to the main process, the control unit 60 displays the processing history screen and the status screen on the display unit 57A (S9).

[0098] Referring to Figure 10, the processing history screen will be explained. For example, the control unit 60 displays the results when the processing schedule set by the operator is executed. The execution results of the processing steps are displayed in order from the newest to the oldest processing steps. The time each processing step was executed, the model of the machine tools 1A and 1B, the stocker address, the product number, the product name, the lot number, the continuous operation status, and the operating time can be visually confirmed.

[0099] Machine tool 1A is executing machining processes ST1 and ST2. For example, machining processes ST1 and ST2 can be seen as having been completed without any program errors or clamping errors.

[0100] Meanwhile, machine tool 1B is executing machining process ST1. Machining process ST1 occurs when there is an abnormality in the cleaning program. Although not shown in the diagram, machine tool 1B is executing the next machining process ST2 without executing the cleaning program.

[0101] Machine tool 1A is executing machining processes ST3 to ST5. It can be seen that machining process ST3 was skipped, for example, due to an abnormality in the NC program. It can be seen that machining process ST4 was skipped, for example, due to a clamping abnormality. It can be seen that machining process ST5 was completed without any program abnormalities or clamping abnormalities.

[0102] The status screen will be explained with reference to Figure 11. The status screen is displayed on the display unit 57A by the operator's operation unit 57B. The status screen displays the status of the pallets P placed on the front stocker and rear stocker. On the status screen, the triangle pointing to the left corresponds to machine tool 1A, and the triangle pointing to the right corresponds to machine tool 1B.

[0103] The front stocker displays the status of stockers No. 1 through No. 15. Stockers No. 1 through No. 5 indicate that the workpiece has been processed by machine tool 1A. Stockers No. 1 through No. 5 are displayed, for example, as a left-facing triangle and in green. Stocker No. 6 indicates, for example, a workpiece that has been stopped by the machine during NC program execution. Stocker No. 6 is displayed, for example, as a left-facing triangle and in red.

[0104] Stocker No. 7 indicates, for example, a state where no workpiece is placed on pallet P. Stocker No. 7 is represented, for example, by a gray circle. Stockers No. 8 to No. 12 indicate pallets P to be used in the machining process of the upcoming machining schedule. Stockers No. 8 to No. 12 are represented by left-facing triangles and are in orange.

[0105] Stocker No. 13 and No. 14 indicate that there is no palette P. Stocker No. 13 and No. 14 are, for example, blank and nothing is displayed. Stocker No. 15 indicates that the status of palette P cannot be determined. For example, the display for stocker No. 15 is a left-facing triangle and is displayed in light blue.

[0106] The rear stocker displays stocker numbers 16 through 40. Stocker numbers 16 through 18 indicate the workpieces to be processed. Stocker numbers 16 through 18 are displayed as left-facing triangles in orange. Stocker numbers 19 and 20 indicate that no workpieces are placed on the pallet. Stocker numbers 19 and 20 are displayed as gray circles.

[0107] Stockers No. 21-26, No. 29, and No. 30 indicate that the workpieces have been processed by machine tool 1B. Stockers No. 21-26 are displayed as right-facing triangles in green. Stockers No. 27 and No. 28 indicate that the machine stopped while the NC program was running on machine tool 1B. Stockers No. 27 and No. 28 are displayed as right-facing triangles in red. Stockers No. 29 and No. 30 are in the same state as stockers No. 21-26.

[0108] Stockers No. 31 to No. 35 indicate workpieces that are scheduled to be machined by machine tool 1B. Stockers No. 36 to No. 38 indicate that pallet P is not placed on them. Nothing is displayed in the columns for stockers No. 36 to No. 38. Stockers No. 39 and No. 40 indicate that they are to be machined by machine tool 1B, but the condition of pallet P cannot be determined.

[0109] The operator can check the status of the pallet P on the conveying device 1C. The display can be updated as needed. For example, the display can be updated when each processing step is completed.

[0110] Once the display process in S9 is complete, the control unit 60 returns to processing S1 and waits.

[0111] <Effects of this embodiment> As described above, the control unit 60 determines whether or not there is an abnormality in each processing step. The control unit 60 decides to skip the processing step in which an abnormality is determined to exist. The control unit 60 decides to execute the processing steps after the processing step that was decided to be skipped, in which no abnormality is determined to exist.

[0112] The control system 1 described above skips machining processes that are judged to have abnormalities and executes machining processes that do not have abnormalities. Since there is no need to stop the machine tools 1A and 1B, the control system 1 can suppress a decrease in productivity.

[0113] The control unit 60 determines that there is an abnormality in the machining process if there is an abnormality in the NC program executed for each machining process. The control system 1 cannot properly machine the workpiece if there is an abnormality in the NC program of the machining process. The control system 1 can suppress the decrease in productivity by skipping the machining process in which there is an abnormality in the NC program.

[0114] The control unit 60 determines that there is an abnormality in the machining process if the workpiece, which has been loaded into the machine tools 1A and 1B by the robot arm 40, is not clamped to the table 25B of the machine tools 1A and 1B. The control system 1 cannot properly machine the workpiece if it is not clamped to the table 25B. The control system 1 can suppress the decrease in productivity by skipping the machining process in which there is an abnormality in the clamping.

[0115] Machine tools 1A and 1B are equipped with sensors 77. Sensors 77 detect whether a workpiece is clamped to the table 25B. The control unit 60 determines whether there is an abnormality based on the detection result of the sensors 77. The control system 1 can accurately detect clamping abnormalities by checking the detection result of the sensors 77.

[0116] The machining process further includes cleaning the machine tools 1A and 1B. The control unit 60 determines, for each machining process, whether there is an abnormality in the cleaning program for cleaning the machine tools 1A and 1B. If the control unit 60 determines that there is an abnormality in the cleaning program, it decides to skip only the cleaning of machine tools 1A and 1B from the machining process. The control unit 60 then decides to execute the machining process that follows the skipped machining process and is determined to be free of abnormalities. If there is an abnormality in the cleaning program, the control system 1 skips only the cleaning of machine tools 1A and 1B from the machining process and executes the machining. Even if the cleaning of machine tools 1A and 1B is not performed, the control system 1 does not stop machine tools 1A and 1B and executes the next machining process. Therefore, the control system 1 can suppress a decrease in productivity.

[0117] The control unit 60 sets the skipping of machining processes to be enabled or disabled. If the skipping of machining processes is disabled and the control unit 60 determines that there is an abnormality in the machining process, it decides to stop the machine tools 1A and 1B. The user can choose to either skip the abnormal machining process and continue with the machining processes without abnormalities, or stop the machine tools 1A and 1B if there is an abnormality in the machining process.

[0118] The control unit 60 is executed before the robot arm 40 loads the workpiece into the machine tools 1A and 1B. The control system 1 can prevent the robot arm 40 from loading the workpiece into the machine tools 1A and 1B if there is an abnormality in the machining process and machining is not possible.

[0119] The control unit 60 notifies the user of the existence of a processing step that has been decided to be skipped. The user can then recognize the existence of the skipped processing step.

[0120] <Modifications> The present invention is not limited to the above embodiments and can be modified in various ways. The technologies disclosed in the above embodiments and modifications can be combined to the extent that they do not contradict each other. Machine tools 1A and 1B were vertical machine tools in which the Z-axis of the spindle 24 extends in the vertical direction, but are not limited to this. Machine tools 1A and 1B may also be horizontal machine tools in which the spindle 24 extends in the horizontal direction.

[0121] In the above embodiment, the control unit 60 of the transport device 1C controlled the entire system of the control system 1, but this is not limited to this. For example, the control system 1 may be controlled by the control unit 70 of the machine tool 1A, or by the control unit 70 of the machine tool 1B. Control may also be distributed among the control units 60, 70, 70. Furthermore, for example, a control device that controls the transport device 1C and the machine tools 1A and 1B according to a processing schedule may be included in the control system 1. The control device may be, for example, a PC, smartphone, tablet, etc.

[0122] In the above embodiment, the machine tools 1A and 1B were controlled by numerical control devices 10, 10, but this is not limited to this. The operation of the machine tools 1A and 1B may also be operated by a user.

[0123] In the above embodiment, the conveying device 1C delivered pallets P to machine tools 1A and 1B, but it is not limited to this. For example, the conveying device 1C may supply pallets P only to machine tool 1A, or it may supply pallets P only to machine tool 1B. In this case, either machine tool 1A or 1B may not be provided.

[0124] In the above embodiment, the processing schedule consisted of processing steps B1 to B6, but it is not limited to this. The processing steps in the processing schedule can be edited as appropriate.

[0125] In the above embodiment, a cleaning program was executed during the machining process, but this is not limited to that. Alternatively, a maintenance program other than the cleaning program may be executed to perform maintenance on the machine tools 1A and 1B. For example, the machine tools 1A and 1B do not necessarily have to execute the cleaning program.

[0126] In the above embodiment, abnormalities in the clamp were confirmed by the air pressure of the air sensor, but this is not limited to that. A sensor 77 for detecting the clamp may be provided in addition to the air sensor. For example, abnormalities may be confirmed from the clamping and unclamping signals to the clamping mechanism.

[0127] In the above embodiment, processing history information and status information are displayed, but the embodiment is not limited to this. For example, only one of them may be displayed. Processing history information and status information may be displayed on machine tools 1A and 1B. The display method of processing history information and status information may be changed as appropriate.

[0128] In the above embodiment, the presence or absence of abnormalities in the NC program and clamping was checked in real time, but this is not limited to this. For example, all NC programs may be checked for abnormalities once the machining schedule is finalized. Even in this case, however, it is necessary to check for unclamping abnormalities for each machining process.

[0129] In the above embodiment, the machine tools 1A and 1B determined the abnormality of the NC program one by one, but the transport device 1C may also perform this determination. The machine tools 1A and 1B only need to transmit the information necessary for determining the abnormality to the transport device 1C. The same applies to determining the abnormality of the clamp. In other words, the control unit 60 may directly analyze the signal from the sensor 77.

[0130] In the above embodiment, the conveying device 1C was capable of accommodating pallets P, but it is not limited to this. For example, the conveying device 1C does not need to accommodate pallets P. For example, the conveying device 1C may be configured to load and unload pallets P into and out of a storage device.

[0131] Instead of the control unit 60, an ASIC, FPGA (Field Programmable Gate Array), etc., may be used as the processor. Each process may be distributed among multiple processors. The numerical control device 10 may include other non-temporary storage media, such as an HDD. The non-temporary storage media can be any storage medium capable of retaining information regardless of the storage period. The non-temporary storage media does not have to include temporary storage media (e.g., transmitted signals).

[0132] Various programs may be downloaded (i.e., transmitted as a transmission signal) from a server connected to a network not shown in the diagram, and stored in memory such as an HDD. In this case, it is sufficient for the various programs to be stored on a non-temporary storage medium such as an HDD provided on the server.

[0133] <Other> In the above description, the sensor 77 is an example of the "detection unit" of the present invention. The CPU 61 that executes the processes in S101 and S105 is an example of the "first decision process" of the present invention. The CPU 61 that executes the processes in S125 and S135 is an example of the "first determination process" of the present invention. The CPU 61 that executes the process in S107 is an example of the "second determination process" of the present invention. The CPU 61 that executes the process in S113 is an example of the "second decision process" of the present invention.

[0134] The CPU 61 that executes the process in S115 is an example of the "third decision process" of the present invention. The CPU 61 that executes the process in S107 is an example of the "fourth decision process" of the present invention. The CPU 61 that executes the process in S3 is an example of the "setting process" of the present invention. The CPU 61 that executes the processes in S121 and S131 is an example of the "fifth decision process" of the present invention. The CPU 61 that executes the processes in S127 and S137 is an example of the "notification process" of the present invention.

[0135] The control of the control unit 60, which executes the main processing and the processing, is an example of the "control method" of the present invention. The processing program is an example of the "program" of the present invention. The control unit 60 is an example of the "computer" of the present invention. The transport device 1C is an example of the "transport device" of the present invention.

[0136] 1: Control system 1A, 1B: Machine tool 1C: Conveying device

Claims

1. A control system comprising a control unit that performs a processing step of transporting a workpiece into a machine tool by a transport device, processing the transported workpiece in the machine tool, and transporting the processed workpiece out of the machine tool by the transport device, multiple times, wherein the control unit performs: a first determination process that determines whether or not there is an abnormality in each of the processing steps; a first decision process that decides to skip the processing step for which the first determination process determined to have an abnormality; and a second decision process that decides to execute the processing step after the processing step for which the first decision process decided to skip, for which the first determination process determined to have no abnormality.

2. The control system according to claim 1, characterized in that the first determination process determines that there is an abnormality in the machining process if there is an abnormality in the NC program executed for each machining process.

3. The control system according to claim 1, characterized in that the first determination process determines that there is an abnormality in the machining process if the workpiece that has been transported to the machine tool by the transport device is not clamped to the table of the machine tool.

4. The control system according to claim 3, wherein the machine tool is equipped with a detection unit that detects whether the workpiece is clamped to the table, and the first determination process determines whether or not there is an abnormality based on the detection result of the detection unit.

5. The control system according to claim 1, wherein the processing step further includes maintenance of the machine tool, and the control unit performs, for each processing step, a second decision process to determine whether or not there is an abnormality in the maintenance program for performing the maintenance; a third decision process to decide to skip only the maintenance among the processing steps if the second decision process determines that there is an abnormality in the maintenance program; and a fourth decision process to decide to execute the processing step after the processing step that was skipped in the third decision process, which the first decision process determined to be free of abnormalities.

6. The control system according to claim 1, characterized in that the control unit performs a setting process to enable or disable the execution of the first decision process, and a fifth decision process to stop the machine tool if the setting process has disabled the execution of the first decision process and the first judgment process has determined that there is an abnormality in the machining process.

7. The control system according to claim 1, characterized in that the first decision process is performed before the workpiece is transported to the machine tool by the transport device.

8. The control system according to claim 1, characterized in that the control unit performs a notification process to notify the existence of the processing step that was decided to be skipped in the first decision process.

9. A control method for a control system that performs a processing step of transporting a workpiece into a machine tool by a transport device, processing the transported workpiece in the machine tool, and transporting the processed workpiece out of the machine tool by the transport device, multiple times, characterized by performing: a first determination step of determining whether or not there is an abnormality in each of the processing steps; a first decision step of deciding to skip the processing step for which an abnormality was determined in the first determination step; and a second decision step of deciding to execute a processing step after the processing step for which it was decided to skip in the first decision step, for which no abnormality was determined in the first determination step.

10. A program characterized in that the computer of a control system that executes a machining process multiple times, which involves transporting a workpiece into a machine tool using a transport device, machining the transported workpiece in the machine tool, and transporting the machined workpiece out of the machine tool using the transport device, functions as: a first determination unit that determines whether or not there is an abnormality in each of the machining processes; a first decision unit that decides to skip the machining process for which the first determination unit has determined there is an abnormality; and a second decision unit that decides to execute the machining process after the machining process for which the first decision unit has decided to skip, for which the first determination unit has determined there is no abnormality.

11. A conveying device comprising a control unit that performs a processing step of loading a workpiece into a machine tool, having the machine tool process the loaded workpiece, and loading the processed workpiece from the machine tool, multiple times, wherein the control unit performs: a first determination process that determines whether or not there is an abnormality in each of the processing steps; a first decision process that decides to skip the processing step for which the first determination process determines there is an abnormality; and a second decision process that decides to execute the processing step after the processing step for which the first decision process decided to skip, for which the first determination process determined there is no abnormality.

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