JP6626165B2 - Machining system with a machine tool and a robot for attaching and detaching workpieces - Google Patents

Description

  The present invention relates to a machining system including a machine tool and a robot for attaching and detaching a workpiece.

  In recent years, a processing system provided with a robot for attaching and detaching a workpiece to and from a machine tool has been used. In this processing system, a robot carries a workpiece into a machine tool, and the machine tool processes the workpiece. After the machine tool processes the work, the robot carries the work out of the machine tool.

  Japanese Patent Laying-Open No. 61-125752 discloses that an actuator is operated by a hydraulic cylinder or a rotary cylinder incorporated in a chuck device of a machine tool. It is disclosed that when the actuator is operated, a plurality of liners are moved to automatically attach and detach the workpiece to and from the chuck device.

JP-A-61-125752

  When a work is attached or detached using a robot, a system that automatically operates without human intervention can be constructed by controlling the fixing device that fixes the work to the machine tool with the control device. In a conventional processing system, a fixing device for fixing a work to a machine tool is driven by hydraulic pressure or pneumatic pressure.

  In a hydraulic or pneumatic fixing device, a piston for driving a claw portion is arranged, and the piston is driven by hydraulic or pneumatic pressure. However, in the case of a hydraulic or pneumatic fixing device, it takes time to hold or release the work without finely adjusting the position of the piston. For example, in the case of a hydraulic or pneumatic fixing device, a claw for holding a work is most open when the work is mounted. Since the robot was stopped during the period in which the claw portion was driven, the robot required a waiting time to carry in the work.

The processing system of the present invention includes a machine tool including a fixing device for fixing a work, a robot for attaching a work before processing to the fixing device, and removing a work after processing from the fixing device, and a robot attached to a tip of an arm of the robot. A hand, a machine tool, a robot, and a control device that controls the hand, and a detector that detects the position and orientation of the robot . The fixing device includes a plurality of moving holding members that hold the work, and a holding member drive motor that moves the moving holding member, and holds or releases the work by moving the moving holding member. The moving holding member includes a first moving holding member that presses a region other than the region where the work is processed, and a second moving holding member that presses a region where the work is processed. When the region pressed by the second moving holding member is processed by the machine tool, the control device causes the second moving holding member to be retracted from the work during the processing period of the work, and then performs the second movement. The machine tool is controlled so as to process an area pressed by the holding member. When the work is fixed to the fixing device while being held by the hand, the work moves by being pressed by the moving holding member. The control device changes the position and posture of the robot so as to follow the movement of the work, calculates the position of the hand based on the position and posture of the robot, and controls the hand before and after the work is held by the fixing device. Based on the position, the amount of movement of the work when the robot follows the robot is calculated, and based on the amount of movement of the work, the relative position of the tool with respect to the work at the time of processing is corrected. The machine tool is controlled so as to perform the machining.

  In the above invention, the hand can include a gripping member that grips the work, and a gripping member drive motor that drives the gripping member.

  In the above invention, the control device includes a robot control device that controls the robot, and a machine tool control device that controls a drive motor of a moving axis of the machine tool, and the fixing device is controlled by the robot control device. it can.

In the above invention, the fixing device comprises a detector for detecting the position of the movable holding member, the control device, based on the position of the movable holding member when holding the workpiece with the movable holding member is held in the workpiece Can be calculated.

  In the above invention, the hand includes a detector that detects a driving state of the gripping member, and the control device controls the gripping member of the workpiece based on the driving state of the gripping member when gripping the workpiece with the gripping member. The dimensions of the portion to be gripped can be calculated.

  In the above invention, the control device corrects the relative position of the tool with respect to the workpiece when performing the processing based on the calculated dimension of the workpiece, and performs the processing of the workpiece at the corrected relative position. Can be controlled.

In the above invention, the fixing device includes a plurality of holding member drive motors that individually drive the plurality of moving holding members, and the control device drives the plurality of holding member drive motors in synchronization, so that the fixing device includes: The position of the work can be changed.

  According to the present invention, it is possible to provide a machining system that includes a machine tool and a robot that attaches and detaches a work to and from the machine tool, and that can perform attachment and detachment of the work in a short time.

It is a schematic perspective view of the processing system provided with the 1st fixing device in an embodiment. It is a block diagram of a processing system in an embodiment. It is another schematic perspective view of the processing system provided with the 1st fixing device in embodiment. FIG. 4 is an enlarged plan view when a work is fixed to a first fixing device. 5 is a flowchart illustrating control of the processing system according to the embodiment. It is a flowchart following the flowchart of FIG. It is a schematic front view explaining movement of a work at the time of fixing a work to a 1st fixing device. It is a schematic perspective view of the 2nd fixing device in an embodiment. It is another schematic perspective view of the 2nd fixing device in embodiment. It is a schematic perspective view of the 3rd fixing device in an embodiment. It is a perspective view of the work processed using a 3rd fixing device. It is a front view of the work processed using a 3rd fixing device. FIG. 11 is a schematic front view showing a first state when a work is fixed by a third fixing device. FIG. 11 is a schematic front view showing a second state when a work is fixed by a third fixing device.

  The processing system according to the embodiment will be described with reference to FIGS. The processing system according to the present embodiment includes a machine tool that processes a workpiece with a predetermined tool, and a robot that attaches and detaches the workpiece to and from the machine tool.

  FIG. 1 shows a schematic perspective view of a processing system in the present embodiment. In the processing system 100 of the present embodiment, the work 9 to be processed by the machine tool is replaced by the robot 2. The machine tool according to the present embodiment is a numerical control type. That is, the machine tool can automatically process the work 9 based on a processing program created in advance. The machine tool according to the present embodiment includes first fixing device 4 fixed to table 11. The work 9 is fixed to the table 11 via the fixing device 4.

  The processing system 100 includes the robot 2 that attaches the work 9 before processing to the fixing device 4 and removes the work 9 after processing from the fixing device 4. The processing system 100 includes the hand 3 attached to the tip of the arm 21 of the robot 2. The hand 3 is fixed to the wrist 22 of the arm 21. The robot 2 in the present embodiment is an articulated robot. The articulated robot of the present embodiment can freely change the position and posture of the wrist 22 of the arm 21. The robot 2 in the present embodiment can arrange the work 9 at a predetermined position and posture.

  The fixing device 4 includes a frame 41 fixed to the table 11. The frame 41 of the present embodiment is formed in a box shape. The frame 41 has a cavity inside. The fixing device 4 includes a plurality of holding members that hold the work 9. The holding member includes a fixed holding member 47 fixed to the frame 41 and immovable with respect to the frame 41, and a movable holding member 42 moving with respect to the frame 41. The work 9 of the present embodiment is formed such that the planar shape becomes a quadrangle.

  The movable holding member 42 is arranged at a position where the work 9 can be sandwiched together with the fixed holding member 47. In this embodiment, two fixed holding members 47 and one moving holding member 42 sandwich the work 9 in one direction of the work 9. In addition, one fixed holding member 47 and one moving holding member 42 sandwich the work 9 in a direction perpendicular to one direction of the work 9.

  The fixing device 4 includes a first drive motor 43 as a holding member drive motor that moves the moving holding member 42. A guide portion 46 is formed on the movable holding member 42. The guide 46 is inserted into a groove formed in the frame 41. The groove extends in the movement direction of the movement holding member 42. The movement holding member 42 moves along the groove. The movement holding member 42 in the present embodiment is driven by a rack and pinion mechanism. The torque of the first drive motor 43 is amplified by the speed reducer 45. When the first drive motor 43 is driven, the movement holding member 42 moves in a direction toward the work 9 and in a direction away from the work as indicated by an arrow 101.

  The hand 3 includes a hand body 31 and a claw portion 32 as a gripping member for gripping a work. The hand main body 31 includes a second drive motor as a gripping member drive motor that drives the gripping member. When the hand drive motor is driven, the claw portion 32 opens and closes. In the example shown in FIG. 1, the hand 3 can grip the work 9 by opening the claw 32 and release the work 9 by closing the claw 32. The work 9 of the present embodiment includes a hole 91 having a substantially circular planar shape. The hole 91 corresponds to a portion gripped by the claw 32. The work 9 is gripped by the engagement of the claws 32 with the inner surface of the hole 91 of the work 9. Note that the hand is not limited to this form, and can grip and release the work in any form.

  FIG. 2 shows a block diagram of a processing system according to the present embodiment. Referring to FIGS. 1 and 2, processing system 100 in the present embodiment includes a control device that controls machine tool 1, robot 2, and hand 3. The control device according to the present embodiment includes a machine tool control device 7 that controls the machine tool 1 and a robot control device 6 that controls the robot 2 and the hand 3. The machine tool controller 7 and the robot controller 6 are connected to each other by a communication device including a communication line 15. The communication device can perform communication by, for example, Ethernet (registered trademark).

  The machine tool control device 7 includes an operation control unit 71 and a storage unit 73. The operation control unit 71 controls the drive motor 12 attached to each moving axis of the machine tool 1 such as the X axis, the Y axis, and the Z axis. In the machine tool 1, the relative position of the tool with respect to the table 11 changes when the drive motor 12 of the moving shaft is driven. That is, the machine tool 1 can process the work 9 while changing the relative position of the tool with respect to the work 9. The storage unit 73 stores a processing program for processing the work 9 and the like.

  The robot control device 6 includes an operation control unit 61 and a storage unit 63. The operation control section 61 controls the arm drive motor 23 of the robot 2. When the arm drive motor 23 is driven, the position and the posture of the robot 2 change. Further, the operation control section 61 controls the second drive motor 33 that drives the claw section 32 of the hand 3. The operation control section 61 adjusts the opening angle of the claw section 32 of the hand 3 by controlling the second drive motor 33.

  Further, the robot control device 6 according to the present embodiment controls the fixing device 4. The operation control section 61 controls the first drive motor 43 of the fixing device 4. The operation control section 61 controls the position of the movable holding member 42. The storage unit 63 stores an operation program for operating the robot, information detected by the detector, calculated information, and the like.

  The robot control device 6 includes a position detection unit 62. The fixing device 4 includes a detector that detects the position of the holding member. The fixing device 4 in the present embodiment includes a rotation angle detector 44 that detects the rotation angle of the first drive motor 43. In the present embodiment, a rotation angle detector 44 is disposed at an end of the first drive motor 43. The rotation angle detector can be constituted by an encoder or the like. The rotation angle of the first drive motor 43 can be detected from the output of the rotation angle detector 44. The position detecting section 62 can detect the position of the moving holding member 42 based on the detected rotation angle. The position of the movable holding member 42 may be, for example, a coordinate value of a predetermined point of the movable holding member 42 in a predetermined coordinate system of the machine tool.

  The robot 2 includes a detector that detects a position and a posture of the robot 2. The robot 2 in the present embodiment includes a rotation angle detector 24 that detects a rotation angle of the arm drive motor 23. From the output of the rotation angle detector 24, the rotation angle of the arm drive motor 23 can be detected. The position detection unit 62 of the robot control device 6 can detect the position and the posture of the robot 2 based on the detected rotation angle. Alternatively, the position detection unit 62 can calculate the position and the posture of the hand 3 based on the position and the posture of the robot 2.

  The hand 3 includes a detector that detects a driving state of the claw 32 as a gripping member. The hand 3 in the present embodiment includes a rotation angle detector 34 that detects the rotation angle of the second drive motor 33. The position detector 62 of the robot controller 6 can detect the driving state of the claw 32, that is, the opening angle of the claw 32, based on the output of the rotation angle detector 34.

  FIG. 1 shows a state before the work is arranged on the fixing device. The movement holding member 42 is arranged at a position away from the region where the work 9 is arranged so as not to contact the work 9. In this state, the robot 2 arranges the work 9 in a region surrounded by the movable holding member 42 and the fixed holding member 47, as shown by the arrow 110. The robot 2 arranges the work 9 such that the work 9 contacts the mounting surface 41a of the frame 41.

  FIG. 3 shows a schematic perspective view when the work is fixed to the first fixing device of the present embodiment. After the robot 2 arranges the work 9 on the mounting surface 41a of the frame 41, the plurality of moving holding members 42 move toward the work 9 as shown by the arrow 103.

  When the work 9 is held by the fixing device 4, the work 9 moves by being pressed by the moving holding member 42 while being held by the hand 3. The robot control device 6 according to the present embodiment has a function of changing the position and posture of the robot 2 so as to follow the movement of the work 9. The robot control device 6 detects the magnitude of the external force applied to the robot 2 and the direction of the external force based on the current supplied to the arm drive motor 23 and the position and orientation of the robot 2 output by the rotation angle detector 24. I do. The operation control unit 61 drives the arm drive motor 23 so as to change the position and the posture of the robot 2 in a direction in which an external force is applied. The robot control device 6 can make this function effective when the work is pressed by the movement holding member 42. With this control, the work can be pressed by the movable holding member 42 and the work 9 can be brought into close contact with the fixed holding member 47.

  By moving the plurality of movable holding members 42 toward the work 9, the work 9 is held by the movable holding member 42 and the fixed holding member 47 in a plurality of directions. Then, while the work 9 is being held, a current is continuously supplied to the first drive motor 43. For this reason, during the period of holding the work 9, a force for moving the moving holding member 42 toward the work 9 is applied.

  The robot 2 retracts after the fixing device 4 fixes the work 9. The hand 3 closes the claw portion 32 when the second drive motor 33 is driven. The engagement of the claw portion 32 is released. Next, as shown by an arrow 102, the arm 3 of the robot 2 moves in a direction away from the work 9, so that the hand 3 separates from the work 9.

  Thus, the robot 2 can attach the workpiece 9 before processing to the fixing device 4. Next, the machine tool 1 processes the work 9. After the processing of the work 9 is completed, the robot 2 removes the processed work 9 from the fixing device 4. At this time, the work 9 can be removed from the fixing device 4 in a procedure reverse to the procedure for attaching the work 9.

  That is, the machine tool control device 7 moves the table 11 and arranges the fixing device 4 at a predetermined position. Next, the robot control device 6 sets the claw portion 32 of the hand 3 in a closed state. The robot controller 6 inserts the claw 32 into the hole 91 of the work 9 by driving the robot 2. Next, the robot control device 6 opens the claw portion 32 of the hand 3 and holds the workpiece 9 with the hand 3. Next, the robot controller 6 releases the holding of the work 9 by moving the plurality of movable holding members 42 in a direction away from the work 9. With the work 9 held by the robot 2, the fixing of the work 9 by the fixing device 4 can be released. Thereafter, the robot 2 is driven to separate the work 9 from the fixing device 4. Then, the robot 2 transports the work 9 to a place where the processed work 9 is arranged.

  The fixing device 4 in the present embodiment can move the movement holding member 42 by the first drive motor 43. Although the moving distance of the holding member is not adjusted in the hydraulic or pneumatic fixing device, the fixing device in the present embodiment can control the position of the holding member to an arbitrary position. When attaching and detaching a workpiece to and from the fixing device, the fixing device can minimize the moving distance of the holding member. For example, the minimum moving distance of the holding member can be determined according to a predetermined work size. For this reason, the time for attaching and detaching the work can be shortened. As a result, the processing time for processing the work can be reduced.

  The fixing device 4 of the present embodiment is fixed to the table 11 of the machine tool 1, but is controlled by the robot control device 6. By employing this configuration, the time required for communication between the machine tool controller 7 and the robot controller 6 can be reduced. The time for attaching and detaching the work 9 to and from the fixing device 4 can be shortened. For example, the robot control device 6 does not need to transmit to the machine tool control device 7 that the work 9 is arranged at a predetermined position on the fixing device 4, and can reduce the waiting time of the robot 2 and the machine tool 1. .

  The fixing device may be controlled by a machine tool control device. Alternatively, the control device for controlling the fixing device can be configured by an independent control device, and can be formed to communicate with the robot control device and the machine tool control device.

  In the fixing device according to the present embodiment, since the movable holding member can be arranged at an arbitrary position, it is possible to process a workpiece having a different shape. That is, the fixing device can fix a plurality of types of works. For example, the fixing device can process works having different sizes. Alternatively, the fixing device can fix a work of any shape that can be fixed by the holding member. For example, the fixing device can fix a workpiece having different vertical dimensions and horizontal dimensions in a planar shape.

  Furthermore, the fixing device of the present embodiment can adjust the force with which the holding member presses the work. In the present embodiment, the operation control unit 61 of the robot control device 6 adjusts the current supplied to the first drive motor 43. By increasing the current supplied to the first drive motor 43, the force for fixing the work 9 can be increased. The current supplied to the first drive motor 43 can be predetermined in the operation program of the robot 2 so as to be adjusted based on the signal received from the machine tool control device 7.

  For example, when machining a workpiece with the machine tool 1, when performing heavy cutting with a large cutting amount, a large force is applied to the workpiece 9. By increasing the current supplied to the first drive motor 43, the operation control unit 61 can firmly fix the work 9 and perform stable processing. On the other hand, in a finishing process or the like for finishing the surface of the work 9, if the work 9 is fixed with a large force, the work 9 may be deformed. When the work 9 is deformed, the processing accuracy is deteriorated. At the time of finishing, since the cut amount is small, the force for holding the work 9 can be reduced. For this reason, at the time of finishing processing, the operation control unit 61 can reduce the current supplied to the first drive motor 43. By reducing the force for fixing the work 9, it is possible to suppress deterioration of the processing accuracy of the work 9.

  Incidentally, a rotation angle detector 44 is attached to the first drive motor 43 of the fixing device 4. The position of the movable holding member 42 can be detected by the rotation angle detector 44. The robot control device 6 of the present embodiment calculates the size of a portion of the work 9 held by the holding member based on the position of the holding member when the work 9 is held by the holding member. In the present embodiment, the robot control device 6 calculates the size of the portion where the workpiece 9 is held based on the position of the moving holding member 42.

  In addition, the hand 3 includes a rotation angle detector 34 that detects a driving state of the second drive motor 33. Based on the rotation angle detected by the rotation angle detector 34, the position of the claw 32, that is, the opening angle of the claw 32 can be calculated. The robot control device 6 calculates the size of the portion of the work 9 gripped by the claw 32 based on the position of the claw 32 when the work 9 is gripped by the claw 32. For example, when the inside diameter of the hole portion 91 of the work 9 is large, the claw portion 32 is in a largely open state. On the other hand, when the inner diameter of the hole portion 91 is small, the claw portion 32 is in a small open state. Thus, the inner diameter of the hole 91 can be calculated by detecting the degree of opening of the claw 32. Further, the robot control device 6 can detect the position and the posture of the robot 2 based on the output of the rotation angle detector 24 of the robot 2.

  Then, the machine tool control device 7 performs machining based on the dimensions of the portion of the work 9 held by the fixing device 4, the size of the portion of the work 9 gripped by the hand 3, and the position and posture of the hand 3. The relative position of the tool with respect to the work 9 when the work 9 is machined by the machine 1 is corrected. Then, the machine tool 1 processes the work 9 at the corrected relative position.

  FIG. 4 shows an enlarged front view of the work when the work is fixed by the first fixing device of the present embodiment. In FIG. 4, an X direction and a Y direction of a machine coordinate system having a predetermined fixed point of the machine tool as an origin are set. The two moving holding members 42 press the work 9 by the first drive motor 43 as shown by an arrow 103. The work 9 includes a dimensional error.

  In the example shown in FIG. 4, a cut portion 93 is formed at the end of the hole 91 of the work 9. An area 94 including the cutting portion 93 is defined. Other parts are inserted into the cutting portion 93 in a later step. In this processing, the cutting portion 93 is formed such that the region 94 is arranged substantially at the center of the width direction of the work 9 in the X direction. In the area 94, a point-symmetric reference point 95 is set. In this example, the reference point 95 is shifted in the X direction from the center point 92 of the hole 91, but this shift may be present. In the Y direction, the cutting portion 93 is formed such that the distance HA between the top of the cutting portion 93 and the top of the hole 91 in the region 94 becomes a predetermined value.

  FIG. 5 shows a flowchart of the control of the robot system when performing the cutting according to the present embodiment. Referring to FIGS. 2, 4 and 5, in step 121, hand 3 grasps work 9 before processing. In step 122, the dimension X1 of the portion of the work 9 gripped by the hand 3 is calculated from the position information (rotation angle) of the second drive motor 33. The robot control device 6 calculates the dimension X1 of the gripped portion based on the opening angle of the claw portion 32. The diameter D of the hole 91 corresponds to the dimension X1.

  Next, in step 123, the robot control device 6 determines whether or not the dimension X1 is within an allowable range. The robot control device 6 includes a determination unit 64, and the determination unit 64 makes a determination. That is, the determination unit 64 determines whether the diameter D of the hole 91 is too large or too small. The permissible range at this time is predetermined. If it is determined in step 123 that the dimension X1 is out of the allowable range, the process proceeds to step 138.

  In step 138, the robot controller 6 determines that the shape of the work 9 is defective. Then, in step 139, the robot control device 6 pays out the work 9. For example, the robot control device 6 releases the grip of the work 9 by the hand 3. Then, the robot control device 6 controls the robot 2 so as to transfer the work 9 to the defective storage location. If it is determined in step 123 that the dimension X1 is within the allowable range, the process proceeds to step 124.

  In step 124, the robot 2 arranges the work 9 on the mounting surface 41a of the fixing device 4. In step 125, the fixing device 4 moves the movable holding member 42 to hold the work 9.

  Next, in step 126, the robot controller 6 calculates a dimension X2 of a portion where the work 9 is held by the holding member based on the position information (rotation angle) of the first drive motor 43. In the present embodiment, the robot control device 6 detects the position of the movement holding member 42 based on the output of the rotation angle detector 44. Then, based on the position of the movable holding member 42 and the position of the fixed holding member 47, the width W of the work 9 is calculated as the dimension X2.

  Next, in step 127, the robot control device 6 detects the position and the posture of the hand 3 based on the position and the posture of the robot 2 detected by the rotation angle detector 24 of the robot 2. Then, the robot control device 6 can calculate the position of the center point 92 of the hole 91 based on the position and posture of the hand 3.

  Next, in step 128, the position difference X3 between the position of the workpiece 9 gripped by the robot 2 and the position fixed to the fixing device 4 is calculated. The robot control device 6 of the present embodiment calculates the distance DX between the center point 92 and the surface held by the fixed holding member 47 in the X direction as the position difference X3. Further, the robot control device 6 calculates the distance DY between the center point 92 and the surface held by the fixed holding member 47 in the Y direction as the position difference X3.

  In step 129, the determination unit 64 of the robot control device 6 determines whether the dimension X2 and the position difference X3 are within the respective allowable ranges. These tolerances are predetermined. If at least one of the dimension X2 and the position difference X3 is out of the allowable range, the process proceeds to step 138. Then, it is determined that the shape of the work 9 is defective, and the work 9 is paid out in step 139. In this way, a defect in the shape of the work 9 can be confirmed before processing.

  In step 129, if the dimension X2 and the position difference X3 are within the respective allowable ranges, the process proceeds to step 130. In step 130, the hand 3 releases the work 9. Then, in step 131, the robot 2 retreats from the work 9. The robot controller 6 sends a signal to the machine tool controller 7 that the fixing of the workpiece 9 by the fixing device 4 is completed.

  FIG. 6 is another flowchart illustrating control of the processing system according to the present embodiment. The flowchart of FIG. 6 continues from the flowchart of FIG. After the work 9 is paid out in step 139 of FIG. 5 because the size X1, X2 or the difference X3 of the position of the work 9 is out of the allowable range, the process proceeds to step 137. Then, in step 137, the determination section 64 determines whether or not the work before processing remains. In step 137, if there is a work before machining, the process returns to step 121 in FIG. 5 and the machining of the work 9 is repeated.

  When the retreat of the robot 2 is completed in step 131 of FIG. 5, the process proceeds to step 132 of FIG. In step 132, a correction amount of the position at the time of processing by the machine tool is calculated based on the dimensions X1, X2 and the difference X3 between the positions. The robot controller 6 sends the actually calculated dimensions X1 and X2 and the position difference X3 to the machine tool controller 7. The machine tool control device 7 includes a correction unit 72. The correction unit 72 corrects the relative position of the tool with respect to the workpiece 9 based on the dimensions X1 and X2 and the position difference X3.

  FIG. 4 shows a reference point 95 of the area 94 when the cutting portion 93 is formed at a desired position. The position of the reference point 95 in the X direction is set at the middle point of the width W of the work 9. The length HL of the region 94 in the Y direction, that is, the length of the cutting portion 93 in the Y direction can be set based on the diameter D of the hole and the predetermined length HA. The width of the region 94 can be set to a predetermined length.

  The relative position of the tool with respect to the workpiece 9 when machining each cutting portion 93, that is, the tool path is set in advance by a machining program of the machine tool. Then, the machine tool control device 7 calculates the correction amount of the tool path based on the position and the length HL of the reference point 95 in the area 94. In the present embodiment, the correction unit 72 calculates the correction amount of the position of the tool with respect to the work 9 in the X direction and the correction amount of the position of the tool with respect to the work 9 in the Y direction. The correction unit 72 generates a corrected tool path based on the correction amount.

  Next, in step 133, the machine tool 1 processes the work 9 using the corrected tool path. Since the tool path is corrected based on the individual difference of the work 9, machining can be performed at a desired position of the work 9. That is, the machine tool 1 can perform processing by correcting a shape error of the work 9. When the machining of the workpiece 9 is completed, the machine tool controller 7 sends a signal indicating that the machining is completed to the robot controller 6.

  Next, in step 134, the robot control device 6 calculates the position and the posture of the robot 2 that grips the processed work 9 with the hand 3. The robot control device 6 can calculate the position of the hole 91 of the work 9 after processing based on the dimensions X1 and X2 and the difference X3 between the positions. For example, the position of the center point 92 of the hole 91 can be calculated. The position and orientation of the robot when the grip of the work 9 is released are stored in the storage unit 63, and the position and orientation of the robot when gripping the processed work are stored based on the stored position and orientation. The posture may be set. With this control, the robot 2 can grip the work 9 by correcting an error in the shape of the work 9.

  Further, in step 134, the robot control device 6 may calculate the dimensions of the portion to be gripped by the work 9 based on the dimensions X1, X2 and the difference X3 between the positions. For example, the robot control device 6 may calculate the dimensions of the hole 91 after processing. Then, the robot control device 6 can calculate the opening angle of the claw portion 32 of the hand 3. By this control, the hand 3 can reliably hold the work 9 after processing.

  Next, in step 135, the robot control device 6 controls the position and the posture of the robot 2 so that the hand 3 can grip the processed work 9. Then, the hand 3 holds the work 9. In step 136, the robot 2 carries out the processed work 9 to a predetermined place.

  Next, in step 137, the robot control device 6 determines whether or not the work before processing remains. In step 137, if there is a work before machining, the process returns to step 121 in FIG. 5 and the machining of the work 9 is repeated. As described above, the processing system 100 of the present embodiment can repeat the processing of the work 9. Multiple workpieces can be processed automatically.

  In the above embodiment, the shape of the work 9 is determined, the tool path of the machine tool is corrected, and the position and orientation of the robot 2 when the work 9 is removed are determined based on the dimensions X1 and X2 and the difference X3 between the positions. Although the correction is performed, the present invention is not limited to this mode, and the determination and the correction may be performed using a part of the dimension X1, X2 and the position difference X3.

  By the way, with reference to FIG. 4, in the above embodiment, the robot control device 6 calculates the size of the portion where the work 9 is held by the holding member based on the position of the moving holding member 42. In particular, the robot control device 6 calculates the width W of the work 9. The calculation of the dimensions of the work 9 is not limited to this mode, and can be calculated based on the amount of movement of the work 9 when the work 9 is held by the movement holding member 42.

  FIG. 7 is a schematic plan view of a portion of the work when the work is fixed by the fixing device. When arranging the work 9 on the mounting surface 41 a of the frame 41, the robot 2 arranges the work 9 inside a region surrounded by the movable holding member 42 and the fixed holding member 47. For example, the work 9 is arranged at the position 90a. In this case, a gap is formed between the work 9 and the movable holding member 42 and between the work 9 and the fixed holding member 47. Then, the robot controller 6 moves the movable holding member 42 as shown by the arrow 103 to bring the work 9 into close contact with the fixed holding member 47. At this time, the robot 2 is driven to follow the external force as described above.

  The work 9 is arranged at a position 90b in close contact with the fixed holding member 47. The center point 92 a of the hole 91 of the work 9 moves in the direction indicated by the arrow 106. Then, the center point moves to a position indicated by the center point 92b of the hole 91.

  The robot control device 6 can calculate the position of the center point 92a and the position of the center point 92b of the hole 91 based on the position information of the hand 3 when the work 9 is mounted. That is, the robot control device 6 can calculate the position of the hand 3 before and after the work 9 is held by the fixing device 4. Then, the robot control device 6 can calculate the moving direction and the moving amount of the center point 92 of the hole 91 indicated by the arrow 106. The movement amount here includes the movement amount in the X direction and the movement amount in the Y direction.

  A reference size serving as a reference for the size of the work 9 and a reference movement amount of the center point 92 of the hole 91 with respect to the work having the reference size are predetermined. Then, the robot control device 6 can correct the dimension of the work 9 based on the reference movement amount and the actual movement amount. For example, when the work 9 is larger than the reference dimension, the movement amount indicated by the arrow 106 is small. On the other hand, when the work 9 is smaller than the reference size, the movement amount indicated by the arrow 106 becomes large. For this reason, the robot control device 6 can calculate the predetermined dimension of the work 9 based on the actually detected movement amount. For example, the robot control device 6 can calculate the distance from the fixed holding member 47 to the center point 92 of the hole 91 based on the movement amount. In particular, the position in the Y direction of the center point 92 of the hole 91 can be calculated based on the amount of movement in the Y direction.

  As described above, the robot control device 6 may calculate the size of the work 9 based on the movement amount of the work 9 when the robot 2 follows the holding of the work 9. Then, the correction unit 72 of the machine tool control device 7 corrects the relative position of the tool with respect to the work 9 when performing the processing. For example, the correction unit 72 can determine the position in the Y direction of the reference point 95 of the area 94 including the cutting unit 93 based on the position of the center point 92 of the hole 91 in the Y direction. Then, the correction unit 72 can correct the relative position of the tool with respect to the workpiece 9 for cutting the cutting unit 93. The operation control unit 71 can control the machine tool 1 to process the work 9 at the corrected relative position.

  FIG. 8 shows a schematic perspective view of the second fixing device in the present embodiment. The second fixing device 5 includes a movable holding member 42 and a fixed holding member 47 that hold the side surface of the work 9, similarly to the first fixing device 4. Further, the second fixing device 5 includes a movable holding member 53 that holds the upper surface of the work 9. The movement holding member 53 presses the work 9 at one end. The frame body 41 includes an overhang portion 54 protruding from the mounting surface 41a. The movement holding member 53 is rotatably supported by the overhang portion 54.

  The second fixing device 5 includes a first drive motor 48 that drives the movement holding member 53. The first drive motor 48 is fixed to an overhang 50 protruding from the side surface of the frame 41. A rotation angle detector 49 for detecting a rotation angle of the first drive motor 48 is attached to the first drive motor 48. The first drive motor 48 is controlled by the robot control device 6.

  A rotating member 51 that rotates together with the output shaft is fixed to the output shaft of the first drive motor 48. One end of a connecting member 52 is connected to the rotating member 51. The other end of the connecting member 52 is formed so as to press the other end of the movable holding member 53.

  FIG. 9 shows a schematic perspective view when the work is fixed by the second fixing device in the present embodiment. Referring to FIGS. 8 and 9, one end of movement holding member 53 moves in the direction indicated by arrow 107 by a mechanism including rotating member 51 and connecting member 52. When the first drive motor 48 is driven, the rotating member 51 rotates. When the rotating member 51 rotates, the connecting member 52 moves. Then, the movable holding member 53 supported by the overhang portion 54 presses the upper surface of the work 9 by rotating. The work 9 is held by the movement holding member 53 pressing the work 9. Then, during the period of holding the work 9, current is supplied to the first drive motor 48, and the movement holding member 53 presses the work 9 as indicated by an arrow 108.

  When processing the work 9, there is a case where a part where the holding member presses the work is processed. For example, referring to FIG. 9, work 9 may be processed in a region where movable holding member 53 is in contact with work 9. In the second fixing device 5 of the present embodiment, the holding member can be moved while the work 9 is being processed. The holding of some of the holding members can be temporarily released.

  For example, when forming a concave portion in a region where the movable holding member 53 is in contact with the work 9, the robot control device 6 drives the first drive motor 48 to move the movable holding member 53 away from the work 9. I do. By retracting the movable holding member 53 from the work 9, the machine tool 1 can process an area where the movable holding member 53 has been in contact with the work 9. After the machining by the machine tool is completed, the robot controller 6 can drive the first drive motor 48 to hold the workpiece 9 with the moving holding member 53.

  As described above, in the processing system including the second fixing device, the moving holding member 53 can be moved while the work 9 is being processed. It is not necessary to change the direction in which the work is fixed or use another fixing device to process the area where the work is held by the moving holding member, and it is possible to perform continuous processing with the same fixing device. it can. As a result, the processing time of the work can be shortened. Further, the third fixing device can change the method of holding the work during the processing period. For example, the part holding the work can be changed according to the part to be processed of the work.

  The holding member that moves during the processing of the work is not limited to the holding member that presses the work from above, and any holding member can be moved. For example, referring to FIG. 9, the moving holding member 42 holding the side surface of the work 9 may be retracted from the work 9 during the processing.

  In some cases, the movable holding member is retracted, and after processing the retracted portion, the processed portion is pressed by the movable holding member. In this case, the operation control unit of the robot control device can correct the dimension of the processed portion of the workpiece by controlling the above-described correction. Then, the operation control unit can drive the movable holding member according to the dimension of the work after the correction.

  Other configurations, operations, and effects of the processing system including the second fixing device are the same as those of the processing system including the first fixing device.

  FIG. 10 is a schematic perspective view of a third fixing device according to the present embodiment. Third fixing device 8 in the present embodiment is arranged on a lathe as a machine tool. The third fixing device 8 is a chuck device that holds the work 10. FIG. 10 shows a state in which the work 10 to be processed is attached to the third fixing device 8. The work 10 is attached to the fixing device 8 by a robot or removed from the fixing device 8 in the same manner as in the machine tool described above. In the lathe according to the present embodiment, the work 10 is attached to or detached from the fixing device 8 by moving the work 10 in the direction in which the rotation shaft 99 extends.

  The fixing device 8 includes a base material 81 formed in a disk shape. The lathe includes a substrate driving motor that rotates the substrate 81 around the rotation shaft 99. When the substrate driving motor is driven, the substrate 81 rotates in the direction indicated by the arrow 109. In the lathe according to the present embodiment, the workpiece 10 rotates around the rotation axis 99 without changing its position during the machining period. The lathe is provided with a cutting tool as a tool. The lathe according to the present embodiment includes a drive motor that moves a cutting tool along a predetermined movement axis. When the drive motor of the moving shaft is driven, the relative position of the tool with respect to the base material 81 changes. That is, the relative position of the tool with respect to the workpiece 10 changes when the drive motor of the moving shaft is driven. The operation control unit of the machine tool control device controls the drive motor of each moving axis and the base material drive motor in the same manner as the above-described machine tool.

  The fixing device 8 includes a moving holding member 82 as a chuck claw that holds the work 10. In the fixing device 8, a plurality of moving holding members 82 are arranged. The movement holding member 82 moves along a guide portion 83 which is a groove formed in the base material 81. The movement holding member 82 moves in the radial direction of the base material 81 as shown by an arrow 101. The work 10 is fixed to the intervening member 84. The intervening member 84 is held by the moving holding member 82. That is, the work 10 is held by the moving holding member 82 via the intervening member 84.

  FIG. 11 is a perspective view of a work held by the third fixing device. FIG. 12 shows a front view of the work held by the third fixing device. Referring to FIGS. 11 and 12, the work 10 is a camshaft of a predetermined device. The work 10 includes a rod-shaped shaft 96 and a circular cam 97 having a circular cross section. Each circular cam 97 is disposed so as to be eccentric with respect to a center axis 98 of the shaft 96.

  Referring to FIG. 10, third fixing device 8 of the present embodiment includes a first drive motor as a holding member drive motor that drives movement holding member 82. The fixing device 8 includes a plurality of first drive motors corresponding to the plurality of moving holding members 82. Each of the first drive motors individually drives the movable holding member 82. In addition, each first drive motor is individually controlled by the operation control unit 61 of the robot control device 6. That is, the position of the movable holding member 82 is independently controlled by the plurality of first drive motors.

  The control device is formed so as to change the position of the work 10 in the fixing device 8 by synchronously driving the plurality of first drive motors. The fixing device 8 changes the relative position of the interposition member 84 with respect to the base material 81, that is, the relative position of the work 10 with respect to the base material 81, while the work 10 is being processed. The position of the work 10 is changed by moving the plurality of moving holding members 82 at the same time.

  FIG. 13 is a schematic front view of the third fixing device and the work in the first state when the work is being processed. FIG. 13 is a diagram when the surface of the shaft 96 is being cut. The work 10 is arranged so that the central axis 98 of the shaft 96 coincides with the rotation axis 99 of the base material 81. In the first state, the plurality of moving holding members 82 are arranged so that the distance from the rotation shaft 99 in the radial direction of the base material 81 is the same. Since the work 10 rotates around the central axis of the shaft 96, the work 10 can be processed so that the cross-sectional shape of the shaft 96 becomes circular.

  FIG. 14 is a schematic front view of the third fixing device and the work in the second state when the work is being processed. When the machining of the shaft 96 is completed, the operation control unit 61 of the robot control device 6 drives the plurality of first drive motors in synchronization. Each moving holding member 82 moves. The operation control unit 61 controls the plurality of first drive motors so as to move the work 10 in parallel while maintaining the state in which the plurality of movement holding members 82 hold the work 10.

  In the second state, the moving holding member 82 is arranged such that the center axis of one circular cam 97 coincides with the rotation axis 99 of the base 81. The intervening member 84 has moved upward in FIG. 14 from the first state shown in FIG.

  In the second state, the center axis of one circular cam 97 and the rotation axis 99 of the base material 81 match. For this reason, the surface of the circular cam 97 can be processed so that the cross-sectional shape of one circular cam 97 becomes circular.

  As described above, in the processing system including the third fixing device, the control device changes the position of the work in the fixing device by synchronously driving the plurality of holding member drive motors. The processing system including the third fixing device can change the position of the work in the fixing device during the period of processing the work. By using the third fixing device, when processing a plurality of portions having different central axes, it is not necessary to replace the intervening member or replace the holding member with a holding member having a different shape. It can be carried out. As a result, the processing time of the work can be shortened.

  Other configurations, operations, and effects of the processing system including the third fixing device are the same as those of the processing system including the first fixing device and the processing system including the second fixing device.

  In each of the above-described controls, the order of the steps can be appropriately changed as long as the function and the action are not changed. The above embodiments can be combined as appropriate.

  In each of the drawings described above, the same or equivalent parts are denoted by the same reference numerals. The above embodiment is an exemplification and does not limit the invention. Further, the embodiments include modifications of the embodiments described in the claims.

DESCRIPTION OF SYMBOLS 1 Machine tool 2 Robot 3 Hand 4,5,8 Fixing device 6 Robot controller 7 Machine tool controller 9,10 Work 15 Communication line 21 Arm 23 Arm drive motor 24 Rotation angle detector 32 Claw 33 Second drive motor 34 Rotation angle detector 41 Frame 41a Mounting surface 42 Moving and holding member 43, 48 First drive motor 44, 49 Rotation angle detector 53 Moving and holding member 62 Position detecting unit 64 Judging unit 72 Correcting unit 82 Moving and holding member 100 Processing system

Claims (7)

A machine tool including a fixing device for fixing a work,
Attaching the workpiece before processing to the fixing device, and removing the workpiece after processing from the fixing device,
A hand attached to the tip of the robot arm,
A control device for controlling the machine tool, the robot and the hand ,
A detector for detecting the position and posture of the robot ,
The fixing device includes a plurality of moving holding members that hold the work, and a holding member drive motor that moves the moving holding member, and holds or releases the work by moving the moving holding member,
The moving holding member includes a first moving holding member that presses a region other than a region where the work is processed, and a second moving holding member that presses a region where the work is processed,
When processing the area pressed by the second movable holding member with the machine tool, the control device may move the second movable holding member away from the workpiece during the processing period of the workpiece, and then perform the second Controlling the machine tool to process the area pressed by the moving holding member ,
When the work is fixed to the fixing device while being held by the hand, the work moves by being pressed by the moving holding member,
The control device changes the position and the posture of the robot so as to follow the movement of the work, calculates the position of the hand based on the position and the posture of the robot, and before the work is held by the fixing device. Based on the position of the hand and the position of the hand after that, the amount of movement of the work when the robot follows the robot is calculated, and based on the amount of movement of the work, the relative position of the tool with respect to the work when performing machining is corrected and corrected. A machining system that controls the machine tool so as to machine a workpiece at a later relative position .   The processing system according to claim 1, wherein the hand includes a gripping member that grips a workpiece, and a gripping member drive motor that drives the gripping member. The control device includes a robot control device that controls the robot, and a machine tool control device that controls a drive motor of a moving axis of the machine tool,
The processing system according to claim 1, wherein the fixing device is controlled by the robot control device. The fixing device includes a detector that detects a position of the moving holding member,
4. The control device according to claim 1, wherein the control device calculates a dimension of a portion where the workpiece is held based on a position of the movable holding member when the workpiece is held by the movable holding member. 5. The processing system described. The hand includes a detector for detecting the driving state of the gripping member,
Wherein the control device, based on the driving state of the gripping member when gripping the workpiece by the gripping member, to calculate the size of the part which is gripped by the gripping members of the workpiece, machining according to claim 2 system.   The control device corrects the relative position of the tool with respect to the workpiece when performing the processing based on the calculated dimension of the workpiece, and controls the machine tool to perform the processing of the workpiece at the corrected relative position. The processing system according to claim 4 or 5. The fixing device includes a plurality of holding member drive motors that individually drive the plurality of moving holding members,
Wherein the control device, the processing system according by synchronously driving a plurality of holding member drive motor to change the position of the workpiece in the fixing device, in any one of claims 1 to 6.

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