JP2020023357A - Box opening apparatus and box opening method - Google Patents

Abstract

To provide a box opening apparatus and a box opening method capable of reducing a box opening failure caused by a tape cutting error.SOLUTION: An opening apparatus 11 cuts tapes 17 and 18 affixed to an opening surface of a box 12 to open the box 12. The opening apparatus includes a height detection device 30 for detecting a position of the tape in an intersecting direction that intersects the opening surface of the box 12 to which the tape is affixed, and a robot 40. A camera 50 and a cutter 53 are attached to a head 44 mounted on a tip of an arm 43 of the robot 40. The camera 50 captures an image of an opening surface 13 from the intersecting direction to obtain a captured image including the opening surface 13. The cutter 53 moves relative to the box 12 and cuts the tapes 17 and 18. A control unit controls a position of the cutter 53 to cut the tapes 17 and 18 along a cutting path of the tapes 17 and 18 determined according to the position in a height direction Z of the tapes 17 and 18 detected by the height detection device 30, and the position of contour of the opening surface in the captured image.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a box opening apparatus and a box opening method for opening a box by cutting a tape attached to the box.

  For example, Patent Literatures 1 to 3 disclose box opening devices that cut a tape stuck along the periphery of a closed flap of a box and open the box. The box opening device (opening device) described in Patent Literature 1 cuts an adhesive tape stuck to an abutting portion of a flap of a cardboard box with a cutter to open the box.

  Further, the box opening devices described in Patent Documents 2 and 3 include a guide plate horizontally supported and a cutter erected on the guide plate, and the guide plate is inserted inside the flap of the box. With the flap lifted slightly, the box is conveyed on a conveyor to cut the tape with a cutter and the box is opened.

JP-A-9-124015 JP-A-59-152133 JP-A-11-91746

  However, in the opening devices described in Patent Literatures 1 to 3, when the insertion depth of the cutter with respect to the tape becomes shallow or the cutter separates from the tape due to variations in the height of the top surface (opening surface) of the box. In addition, the tape is not partially cut, resulting in poor opening of the box. Conversely, if the cutter is inserted too deeply, the contents of the box may be damaged. For this reason, there is a demand for a box unsealing apparatus capable of reducing the unsuccessful opening of the box caused by a mistake in cutting the tape even if the height of the top surface (unsealing surface) of the box slightly varies.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a box opening device and a box opening method that can reduce the unsuccessful opening of a box due to an error in cutting the tape.

Hereinafter, means for solving the above-described problems and the effects thereof will be described.
A box opening device that solves the above-mentioned problem is a box opening device that cuts a tape attached along a peripheral edge of a flap that closes an opening of the box and opens the box, wherein the tape in the box is attached. A position detection unit that detects the position of the tape in an intersecting direction intersecting the opened surface, and an imaging unit that images the unsealing surface from an imaging position separated in the intersecting direction to obtain an image including the unsealing surface. A cutter that moves relative to the box and cuts the tape, a position of the tape in the cross direction detected by the position detection unit, and a position of an outer shape of the opening surface in the captured image. A control unit that controls the position of the cutter along a cutting path of the tape in a control coordinate system determined based on the cutting path of the tape in an image coordinate system and cuts the tape. In addition, the position of the outer shape of the opening surface in the captured image is not limited to the position on the entire circumference of the outer shape, and may be at least a part of the outer shape where the cutting path of the tape can be specified. For example, if the outer shape is a polygon, the position may be at least two vertices of the outer shape.

  According to this configuration, since the cutting path is determined based on the position of the tape in the cross direction intersecting the opening surface and the position of the outer shape of the opening surface in the captured image of the opening surface, the tape position is in the cross direction. The position of the cutter can be properly controlled with respect to the tape even if there is some variation. Therefore, it is possible to reduce the opening failure of the box caused by a mistake in cutting the tape attached to the opening surface of the box.

  In the box opening device, the position detection unit includes a sensor unit movable in the cross direction while emitting detection light in a direction parallel to the opening surface with respect to the box, and the sensor unit moves the sensor unit in the cross direction. And a second moving mechanism for moving the sensor unit in the cross direction to detect the position of the tape in the cross direction, and moving the imaging unit to the imaging position. May be provided.

  According to this configuration, the position detection in the cross direction of the tape and the imaging of the unsealing surface can be performed in parallel by an independent moving mechanism. Compared to a configuration in which the position detection unit and the imaging unit are position-controlled by the same moving mechanism, the cutting path of the cutter can be determined earlier, and the tape cutting operation can be realized at high speed.

  In the box opening device, a distance sensor that measures a distance to the tape in the cross direction is provided, and the control unit detects a plurality of distances to the tape along the cutting path of the tape by the distance sensor. The position of the cutter may be controlled along the cutting path and the position of the cutter may be controlled in the cross direction in accordance with a change in the distance to the tape in a process of cutting the tape.

According to this configuration, the tape can be cut following the dent of the opening surface of the box.
In the box opening device, the second moving mechanism is an articulated robot controlled by the control unit while having an arm to which the imaging unit and the cutter are attached to a tip end, and the distance sensor includes: The arm may be attached to a tip of the arm.

  According to this configuration, since the distance sensor is also attached to the arm of the robot that controls the position of the cutter, a change in the distance to the tape in the cross direction can be measured along the cutting path. Therefore, the tape can be cut following the dent of the opening surface of the box.

  In the box opening device, the position detecting unit is a distance sensor that measures a distance to the tape in the cross direction to detect the position of the tape in the cross direction, and the control unit includes the distance sensor. A plurality of distances to the tape are detected along the cutting path of the tape by a sensor, and the position of the cutter is controlled along the cutting path to cut the tape. The position of the cutter may be controlled in the cross direction accordingly.

According to this configuration, the tape can be cut following the dent of the opening surface of the box.
In the box opening device, the imaging unit is fixed at a predetermined height position at which the opening surface of the box can be imaged, has an arm to which the cutter is attached to a tip end, and is controlled by the control unit. An articulated robot and an elevating mechanism that raises or lowers the box until the opening surface of the box reaches a height position that is the focus of the imaging unit may be provided.

  According to this configuration, there is no need to move the imaging unit. In addition, if the opening and closing mechanism of the box is set so that the opening surface of the box has the opening area of the box at a height where the movable area of the arm with the cutter attached to the tip is wide, the cutter can be taped. The maximum size of the box that can be cut can be increased.

  In the box opening device, further comprising a transport mechanism for horizontally transporting the box along the longitudinal direction of the tape, the control unit, a part of the tape is in the movable area of the cutter, the tape If the other part of the tape is not in the movable area, the cutter cuts the part of the tape and the box until the other part of the tape is located at the cut position in the movable area. And the other part of the tape may be cut by the cutter with a transport operation of transporting the tape horizontally.

  According to this configuration, a part of the tape is in the movable area of the cutter attached to the tip of the arm, and the other part of the tape is also in a box large enough to be out of the movable area of the cutter. The tape can be cut by transporting the box horizontally. It is possible to increase the maximum size of the box from which the tape can be cut for the movable area of the robot arm.

  In the box opening device, the control unit may be configured such that, in a process in which the cutter cuts the tape, an inclination angle of the cutter with respect to a surface of the tape falls within an allowable range according to a change in a distance to the tape. May be controlled.

  According to this configuration, since the position of the cutter is controlled along the cutting path and the inclination angle of the cutter with respect to the surface of the tape is controlled to be within an allowable range in the process of cutting the tape, the cutter is cut when the tape is cut. The load can be reduced. For example, breakage of the cutter is reduced, and the life of the cutter can be extended.

  In the box opening device, a first tape attached to a boundary between the two flaps on an opening surface of the box, and a second tape attached along a boundary between the two flaps and a side surface of the box. And the control unit, the first tape from the position in the cross direction and the position coordinates of a plurality of image coordinate systems including two or more vertices in the outer shape of the unsealing surface in the captured image The cutting path is determined, and the position of the cutter is controlled along the determined cutting path to cut the first tape, the position in the cross direction, and the unsealing surface and the adjacent surface in the captured image. May be determined from the image coordinate system edge line that intersects, and the second tape may be cut by controlling the position of the cutter along a cutting path along the determined edge line.

  According to this configuration, since the position of the cutter is controlled along the cutting path along the edge line where the opening surface and the side surface of the box intersect, even if the side surface of the box is deformed, the cutter follows the curved edge line due to the deformation. To cut the second tape.

  A method of opening a box that solves the above problem is a method of opening a box that cuts a tape stuck along a periphery of a flap that closes an opening of the box and opens the box, wherein the tape in the box is stuck. A position detecting step of detecting a position of the tape in a crossing direction intersecting the opened surface, an imaging step of imaging the opened surface of the box to obtain a captured image, and the tape detected in the position detecting step The cutter along the cutting path of the tape determined based on the position in the cross direction and the cutting path of the tape image coordinate system determined from the outer shape position of the unsealing surface in the captured image obtained in the imaging step. Controlling the position and cutting the tape. According to this method, as in the case of the box opening device, it is possible to reduce the box opening failure caused by a mistake in cutting the tape.

  ADVANTAGE OF THE INVENTION According to this invention, the poor opening of the box resulting from the cutting mistake of a tape can be reduced.

FIG. 2 is a schematic side view showing the box opening system in the first embodiment. FIG. 1 is a schematic front view showing a box opening system. FIG. 4 is a perspective view showing the box positioned at the work position. FIG. 2 is a block diagram showing an electrical configuration of the box opening system. FIG. 4 is a schematic diagram illustrating a method of obtaining a cutting path from the outer shape of the opening surface of the box. FIG. 4 is a schematic diagram illustrating a method for obtaining a cutting path of a second tape. FIG. 4 is a schematic plan view illustrating the operation of a cutter for cutting a second tape. 9 is a flowchart illustrating tape cutting control. (A) is a schematic front view showing a modified example of the height detecting device, and (b) is a schematic front view showing a portion attached to a flap of the first tape. FIG. 9 is a schematic front view illustrating tape cutting control according to a second embodiment. 9 is a flowchart illustrating tape cutting control. The front view showing the box opening system in a 3rd embodiment. The side view which shows the opening device when opening a large-sized box. The side view which shows the opening device when opening a small size box. FIG. 4 is a partially cut-away schematic side view showing a head mounted on an arm. FIG. 2 is a schematic front view showing a head mounted on an arm. The schematic front view which shows a mode that the distance of the vertical direction Z is measured with a distance sensor. FIG. 2 is a schematic front view showing a state of cutting a first tape. FIG. 4 is a schematic front view illustrating the operation of a cutter for cutting a second tape from a large-sized box. 9 is a flowchart illustrating tape cutting control. FIG. 13 is a schematic front view showing a tape cutting control by a head of a comparative example in a modified example. FIG. 3 is a schematic front view illustrating tape cutting control by the head according to the embodiment.

  Hereinafter, an embodiment of a box opening system 10 including a box opening device 11 will be described with reference to the drawings. In the box opening system 10 shown in FIGS. 1 and 2, the height direction of the box 12 is the Z direction, and the direction parallel to the transport direction in which the box 12 is transported is the X direction. The width direction orthogonal to the direction is defined as a Y direction. In the X direction, the direction in which the box 12 is transported is also referred to as the transport direction X1, the two directions Y and Z are also referred to as the width direction Y and the height direction Z.

  A box opening system 10 shown in FIG. 1 and FIG. 2 cuts tapes 17 and 18 from a transport device 20 having a conveyor 21 for transporting the box 12 and the box 12 positioned at a work position SP on the conveyor 21. And a box opening device 11 for performing an opening operation for opening the box 12. In the example shown in FIG. 1, the box 12 is conveyed on the conveyor 21 with the opening surface 13 to be opened facing the top. The opening device 11 cuts the tapes 17 and 18 stuck on the opening surface 13 of the box 12 with the cutter 53 to open the box 12.

  As shown in FIGS. 1 and 2, the transfer device 20 includes a positioning device 22 that positions the box 12 on the conveyor 21 at the work position SP. The positioning device 22 has a stopper device 23 for positioning the box 12 in the transport direction X1, and a pair of guide devices 24 for positioning the box 12 in the width direction Y intersecting the transport direction X1. The stopper device 23 includes a cylinder 25 and a stopper 26 fixed to a tip of a piston rod of the cylinder 25. When the cylinder 25 is in the contracted state, the stopper 26 is disposed at the retreat position below the conveyor 21, and when the cylinder 25 is driven to extend, the stopper 26 projects above the conveyor 21 to move the box 12 in the transport direction X1. The box 12 is located at a regulated position for regulating the box 12 in the transport direction X1.

  As shown in FIGS. 1 and 2, the pair of guide devices 24 are disposed on both sides in the width direction Y sandwiching the working position SP on the conveyor 21, and are fixed to the pair of cylinders 27 and the distal ends of the piston rods of the cylinders 27. And a guide member 28. When the pair of cylinders 27 are driven to extend, the pair of guide members 28 position the box 12 in the width direction Y with the box 12 sandwiched from both sides. The pair of guide devices 24 are driven when the sensor 29 shown in FIG. 2 detects the box 12 positioned in the transport direction X1 by the stopper device 23, and positions the box 12 in the width direction Y.

  As shown in FIG. 1, the opening device 11 includes a height detection device 30 that detects the height position of the opening surface 13 of the box 12 positioned at the work position SP, and an opening surface 13 that is located at the detected height position. And a robot 40 for performing a cutting operation for cutting the tapes 17 and 18 attached to the robot.

  The height detection device 30 detects the height position of the opening surface 13 which is the top surface of the box 12. The height detecting device 30 includes an elevating mechanism 31 and a sensor unit 32 supported by the elevating mechanism 31 so as to be movable (elevated) in the height direction Z. The sensor unit 32 emits the detection light HL indicated by a broken line in FIG. 1 in a horizontal direction toward the upper side of the work position SP, and receives the detection light HL reflected on the object on the light emission path. And a detection unit 33 having: The elevating mechanism 31 includes a rail 34 having a predetermined length extending in the height direction Z, and a motor 35 serving as a power source for moving the sensor unit 32 up and down along the rail 34 in the height direction Z. The sensor unit 32 moves in the height direction Z along the rail 34 by transmitting the power of the motor 35 via a power transmission mechanism (not shown). The power transmission mechanism is, for example, one of a belt type, a wire type, and a ball screw type. The power source of the elevating mechanism 31 may be an electric cylinder instead of the motor 35.

  As shown in FIG. 1, the sensor unit 32 of the height detecting device 30 moves (elevates) in the height direction Z while emitting the detection light HL in a direction parallel to the opening surface 13 of the box 12. The sensor unit 32 is, for example, a laser scanner that emits a laser beam as the detection light HL. The sensor unit 32 detects a switching position between a state in which the detection unit 33 does not detect an object and a state in which the object is detected in the process of moving in the height direction Z as a position in the height direction of the opening surface 13 of the box 12. I do. That is, the height detection device 30 detects the height position of the opening surface 13 of the box 12 based on the presence or absence of reflected light of the detection light HL emitted from the sensor unit 32 that moves in the height direction Z. For example, the sensor unit 32 emits the detection light HL in the horizontal direction while descending at a predetermined speed from a predetermined detection start position higher than the assumed height of the box 12, and receives the reflected light from the box 12. Then, the height position at that time is detected as the height position of the opening surface 13. Thus, the height detection device 30 detects the height position of the unsealing surface 13 of the box 12 to be unsealed by the robot 40. If the opening surface 13 is a horizontal surface, the height position of the opening surface is the height position of the tapes 17 and 18 attached to the opening surface 13. The height direction Z is a direction that intersects (for example, is orthogonal to) the opening surface 13. At this point, the height detecting device 30 detects the positions of the tapes 17 and 18 in a direction intersecting the opening surface 13 on which the tapes 17 and 18 of the box 12 are stuck. The height detection method of the height detection device 30 is not limited to the light detection method of emitting the detection light HL and detecting the reflected light, and may be a method of detecting the height of the opening surface 13 using a sound wave. .

  As shown in FIG. 1, the robot 40 includes a table 41 installed on the floor, a turntable 42 rotatable about a vertical axis with respect to the table 41, and a multi-joint supported by the turntable 42. This is an articulated industrial robot provided with an arm 43 and a head 44 supported at the tip of the arm 43. The arm 43 rotates with the turntable 42 by the power of a power source 45 disposed on the base 41. Further, the arm 43 is configured by a plurality of arm portions 43A to 43D connected so as to be able to change the angle. The angles of the plurality of arm portions 43A to 43D are adjusted via a drive link or the like (not shown) when the drive mechanism 46 is driven. The drive mechanism 46 includes a power source (not shown) such as an electric motor or an electric cylinder. The head 44 is supported by a rotating unit 48 provided with an arm 43D, which is the tip of the arm 43, rotatably provided with a motor (not shown) as a power source. The head 44 is detachably attached to the rotating part 48 of the arm 43D. As described above, the robot 40 of the present example is a six-axis or seven-axis multi-joint robot including six or seven joints including the turntable 42 and the plurality of arm portions 43A to 43D.

  As shown in FIGS. 1 and 2, the head 44 has a supporting portion 49 supported by the rotating portion 48. A camera 50 as an example of an imaging unit and a cutter unit 51 are assembled to the support unit 49. The robot 40 moves the camera 50 to the imaging position shown in FIGS. 1 and 2 where the height is focused on the height position detected by the sensor unit 32, and images the opening surface 13 of the box 12 with the camera 50. The imaging position is set at a position above the opening surface 13 by a predetermined height in a height direction Z orthogonal to the opening surface 13 of the box 12 positioned at the work position SP. The camera 50 captures an image of the opening surface 13 of the box 12 to obtain a captured image including the opening surface 13. Image data captured by the camera 50 is transmitted to the control unit 60 (see FIG. 4). The robot 40 performs an opening operation in which the tapes 17 and 18 attached to the opening surface 13 of the box 12 are cut by the cutter unit 51 attached to the head 44.

As shown in FIGS. 1 and 2, a columnar vibrator 52 constituting the cutter unit 51 is attached to the support 49. A cutter 53 is fixed to the tip of the output shaft of the vibrator 52. The vibrator 52 and the cutter 53 are held in a predetermined posture in which their axes are parallel to the optical axis direction of the camera 50, for example. The cutter unit 51 vibrates the cutter 53 with the ultrasonic waves generated by the vibrator 52, and cuts the tapes 17 and 18 with the vibrating cutter 53. The vibrator 52 is electrically connected to an oscillator (not shown) via a power line (not shown) that passes through the inside or outside of the vibrator along the arm 43, and the ultrasonic wave is generated by a periodically changing voltage supplied from the oscillator. Vibrate. The cutter 53 is moved relative to the box 12 and cuts the tapes 17 and 18 attached to the opening surface 13 by controlling the position and the posture of the cutter 53 by the movement of the arm 43 of the robot 40. That is,
By controlling the posture of the arm 43 of the robot 40 and moving the cutter 53 in the X direction along the opening surface 13, the first tape 17 attached to the opening surface 13 is cut. Further, the robot 40 controls the arm 43 so that the cutter 53 shown by the two-dot chain line in FIG. 2 is tilted, for example, at about 45 degrees, and moves the cutter 53 in the Y direction along the side edge of the opening surface 13. Thereby, the second tape 18 attached to the side edge of the opening surface 13 is cut. The box 12 opened by the robot 40 by cutting the tapes 17 and 18 is carried out by the conveyor 21. The unloaded box 12 is sent to an unillustrated unpacking device arranged downstream of the unsealing system 10 in the transport direction X1. In addition, the unpacking device pushes a plurality of flaps to the outside of the box 12 after the tapes 17 and 18 have been cut to open the box 12 so that the contents can be taken out. Or take out the contents.

  Next, with reference to FIG. 3, the positioning of the box 12 at the work position SP where the box 12 is opened and the tapes 17 and 18 stuck on the opening surface 13 will be described. As shown in FIG. 3, the box 12 is, for example, a cardboard box, and includes a first tape 17 attached along a center line of the opening surface 13 and two of the opening surface 13 intersecting with the first tape 17. It is closed by a so-called "H application" by the second tape 18 attached to the side edge over the opening surface and the side surface. The tapes 17 and 18 are, for example, adhesive tapes.

  Here, the box 12 to be opened will be described with reference to FIG. FIG. 3 shows the unopened box 12 positioned at the working position SP on the conveyor 21. In the example shown in FIG. 3, the box 12 is positioned in the transport direction X1 by being restricted by the stopper 26 in the transport direction X1, and the pair of guide members 28 sandwich the box 12 from both side surfaces 12A so as to have a width. It is positioned in the direction Y. The box 12 has a box body 15 and four flaps 16 (only two outer flaps are shown in FIG. 3) which are folded so as to close the upper opening 12K of the box body 15. Tapes 17 and 18 are applied along the peripheral edges of the pair of upper flaps 16. A first tape 17 (central tape) is adhered so as to extend in the X direction along a boundary between the pair of flaps 16. The first tape 17 is attached along a center line extending in the X direction through the center of the width of the opening surface 13 of the box 12. A second tape 18 (side edge tape) is attached to the box 12 so as to extend in the Y direction along a boundary between both side edges of the pair of flaps 16 and the side surface 12B of the box 12. The opening device 11 includes a first tape 17 attached to the boundary between the two flaps 16 on the opening surface 13 of the box 12, the side of the opening surface 13 along the boundary between the two flaps 16 and the side surface 12 </ b> B of the box 12. The second tape 18 attached to the edge is to be cut.

  As shown in FIG. 3, the first tape 17 attached to the opening surface 13 of the box 12 is cut along a first cutting path L1 shown by a dashed line in FIG. In addition, the second tape 18 attached to the side edge of the opening surface 13 of the box 12 is cut along a second cutting path L2 indicated by a dashed line in FIG. Note that the first cutting path L1 is not at the center of the width of the first tape 17 but at a position corresponding to the boundary between the pair of flaps 16. The second cutting path L2 is not at the center of the width of the second tape 18 but at a position corresponding to the boundary between the side edges of the pair of flaps 16 and the side surface 12B.

  Note that, for example, a depalletizer for taking out the boxes 12 one by one from the group of boxes stacked on the pallet and placing the boxes 12 on the conveyor 21 is disposed upstream of the opening system 10. The depalletizer reads the two-dimensional code written on the box 12 with a reading unit to obtain box specifying information. The control unit 60 of the opening system 10 shown in FIG. 4 receives the box identification information from the depalletizer in advance. The control unit 60 controls the driving of the cylinder 27 in accordance with the size of the box 12 acquired based on the box specifying information to control the position of the pair of guide members 28. Boxes 12 of various sizes are carried on the conveyor 21 shown in FIG. 1 and FIG. 2, but the projecting amount of the cylinder 27 is controlled according to the box specifying information, so that the boxes 12 of any size Y can be positioned.

  Next, an electrical configuration of the opening system 10 will be described with reference to FIG. An operation panel 70 is electrically connected to the control unit 60 of the opening system 10. The operation panel 70 includes a display unit 71. The operator uses the operation panel 70 when the operator performs an operation of inputting various setting data and giving an instruction to start and stop the operation to the opening system 10. The control unit 60 causes the display unit 71 of the operation panel 70 to display a setting screen, a notification screen for notifying an operator of an error, and the like.

  The conveyor 21, the positioning device 22, and the sensor 29, which constitute the transport device 20, are electrically connected to the control unit 60. The robot 40, the camera 50, and the cutter unit 51, which constitute the opening device 11, are electrically connected to the control unit 60. The control unit 60 controls the positioning device 22 based on the detection signal of the sensor 29 to position the box 12 carried in by the conveyor 21 to the work position SP. Further, the control unit 60 controls the height detection device 30 to detect the height positions of the tapes 17 and 18 on the opening surface 13 by the sensor unit 32. The control unit 60 controls the robot 40 to move the camera 50 to the imaging position. The control unit 60 acquires an image captured by the camera 50. The control unit 60 controls the cutter unit 51 to ultrasonically vibrate the cutter 53.

  Further, the control unit 60 includes an image processing unit 61, a calculation unit 62, and a memory 63. The memory 63 stores a cutting control program PR shown in the flowchart of FIG. The control unit 60 has a built-in computer such as a microprocessor. The image processing unit 61 and the calculation unit 62 are configured by software configured by executing a program PR stored in the memory 63 by a computer. The image processing unit 61 and the arithmetic unit 62 may be configured by hardware using an electronic circuit in the control unit 60. Further, the control unit 60 may be configured to be divided into a robot controller that controls the robot 40 and a controller of an opening control system that controls the camera 50 and the cutter unit 51.

  The control unit 60 controls the height positions of the tapes 17 and 18 attached to the opening surface 13 of the box 12 detected by the height detection device 30 and the image CI of the opening surface 13 captured by the camera 50 from the imaging position (FIG. 5). ) Is calculated on the basis of the above. The image processing unit 61 obtains an image CI including the opening surface 13g illustrated in FIG. 5 in which the camera 50 captures the opening surface 13 and performs predetermined image processing on the image CI to obtain the opening surface 13 illustrated in FIG. Get the outline of. The calculation unit 62 performs a geometric calculation from the coordinates of a plurality of points on the outer shape of the opening surface 13, and the first cutting path L <b> 1 and the second cutting path L <b> 1 for the robot 40 to control the position of the cutter 53 by controlling the arm 43. The two cutting paths L2 are obtained. The control unit 60 controls the robot 40 and controls the position of the cutter 53 along the first cutting path L1 and the second cutting path L2.

  Next, the operation of the opening system 10 will be described. The operator operates the operation panel 70 to give an operation start instruction. When receiving the operation start instruction, the control unit 60 starts the operation of the opening system 10. The control unit 60 reads the program PR shown in the flowchart of FIG.

  Note that the control unit 60 receives box specifying information on the boxes 12 carried into the conveyor 21 from the palletizer that performs the unstacking operation of the boxes on the upstream side of the opening system 10. The box identification information includes information such as the product number, shape, and size of the box 12. When a sensor (not shown) detects that the box 12 has been carried into the conveyor 21, the control unit 60 drives the cylinder 25 to move the stopper 26 from the retracted position to the regulating position shown in FIGS. When the box 12 is positioned in the transport direction X1 and the sensor 29 detects the box 12, the pair of cylinders 27 are driven to position the box 12 in the width direction Y with the pair of guide members 28 sandwiching the box. Thus, the box 12 is positioned at the work position SP.

Hereinafter, the opening control in which the control unit 60 executes the program PR shown in the flowchart of FIG.
First, in step S11, the control unit 60 detects the position of the tapes 17 and 18 in the cross direction. That is, the control unit 60 detects the positions (height positions) of the tapes 17 and 18 affixed to the opening surface 13 in the height direction Z which is the cross direction intersecting with the opening surface 13 of the box 12. Specifically, the control unit 60 controls the height detection device 30 to lower the sensor unit 32 from the detection start position, and detects the height position of the opening surface 13. The height position of the opening surface 13 detected at this time corresponds to the position of the first tape 17 applied along the boundary between the two flaps 16 on the opening surface. In the present embodiment, the processing in step S11 is an example of a “position detection step” in which the positions of the tapes 17 and 18 in the intersecting direction intersecting with the unsealing surface 13 on which the tapes 17 and 18 of the box 12 are stuck. Is equivalent to

  In step S12, the control unit 60 moves the camera 50 to the imaging position. That is, the control unit 60 controls the arm 43 of the robot 40 and arranges the camera 50 at an imaging position shown in FIGS. 1 and 2 at a predetermined height above the opening surface 13. The imaging position of the camera 50 is a position above the opening surface 13 of the box 12 by a distance corresponding to the focal length of the camera 50 in the height direction Z. When the camera 50 captures an image of the lower side from this imaging position, the opening surface 13 is focused.

  In step S13, the control unit 60 causes the camera 50 to image the opening surface 13 of the box 12. Specifically, the control unit 60 outputs an imaging command signal to the camera 50. The camera 50 performs an imaging operation when an imaging instruction signal is input. As a result, the camera 50 images the opening surface 13 of the box 12. Image data CI (hereinafter, simply referred to as “image CI”) obtained by capturing the opening surface 13 by the camera 50 is sent to the control unit 60. In the present embodiment, the processing in step S13 corresponds to an example of an “imaging step” for imaging the unsealing surface 13 to which the tapes 17 and 18 of the box 12 are attached.

  In the present embodiment, the camera 50 of the robot 40 and the sensor unit 32 of the height detection device 30 are driven by independent moving systems. In steps S11 and S12, the robot 40 and the height detection device 30 are separately driven based on separately issued instructions from the control unit 60. For this reason, the detection of the position of the tapes 17 and 18 in the cross direction by the sensor unit 32, that is, the detection of the height position of the tapes 17 and 18 in the present example where the cross direction is the height direction Z, The imaging of the opening surface 13 is performed in parallel.

  In step S14, the control unit 60 performs image processing on the image CI including the opening surface 13g. The control unit 60 performs, for example, binarization processing as image processing on the image CI including the opening surface 13g, and generates an image in which the outer shape of the opening surface 13g can be easily grasped. Note that the image processing may be omitted as long as the outer shape of the opening surface of the box can be grasped.

  In step S15, the control unit 60 calculates a tape cutting path. Specifically, the control unit 60 obtains a cutting height for controlling the height of the cutter 53 from the height positions of the tapes 17 and 18 detected by the height detection device 30. In addition, the control unit 60 measures the distance from the height position of the tapes 17 and 18 detected by the height detection device 30 to the tape 17 on the opening surface 13 from the camera 50 at the imaging position (also referred to as “imaging distance”). Ask for. Based on the position of the outer shape of the opening surface 13g in the image CI subjected to the image processing in the image coordinate system, the imaging distance, and the optical parameters of the camera 50, the controller 60 geometrically converts the outer shape of the opening surface 13g in the image CI. The cutting path of the cutter 53 on the XY plane of the camera coordinate system of the opening surface 13 is obtained by logical calculation. That is, the control unit 60 obtains the tape cutting path in the camera coordinate system from the imaging distance when the camera 50 captures the opening surface 13 and the position and size of the opening surface 13g included in the captured image CI. Further, the control unit 60 converts the coordinates of the tape cutting path in the camera coordinate system into the control coordinate system of the robot control.

  Here, by using the outer shape of the opening surface 13g, the first cutting path L1, which is the cutting path of the first tape 17, is not at the width center line of the first tape 17, but at the upper side that closes the opening 12K of the box 12. The position of the boundary between the pair of flaps 16 is determined. The second cutting path L2, which is the cutting path of the second tape 18, is not at the width center line of the second tape 18, but at each boundary between the pair of flaps 16 and the side surfaces 12B on both sides of the box 12 facing each other in the X direction. Determined as the position of the line. The calculation of the first cutting path L1 and the second cutting path L2 is performed by the calculation unit 62 of the control unit 60 as follows.

  As shown in FIG. 5, the calculation unit 62 calculates the coordinates (x1, y1), (x2, y2) of the vertices A, B, C, and D from the outer shape of the opening surface 13g of the box 12g in the image CI after the image processing. , (X3, y3), (x4, y4). Next, the control unit 60 determines the middle point E ((x1 + x2) / 2, (y1 + y2) / 2) of a pair of vertices A and B facing each other in the width direction Y intersecting the longitudinal direction of the first tape 17 and the other. Of the pair of vertices C and D ((x3 + x4) / 2, (y3 + y4) / 2). A line segment EF connecting these midpoints E and F is obtained as a cutting path Ta1 on the xy plane. The arithmetic unit 62 converts the cutting path Ta1 on the xy plane from the image coordinate system to the camera coordinate system, converts the coordinate to the control coordinate system for robot control, and cuts the cutting path Ta1 on the XY plane of the control coordinate system. Find T1. As the coordinates of the cutting position (cutting height) in the Z direction, the coordinates Hz of the height position of the tape 17 detected by the height detecting device 30 are used. Therefore, the first cutting path L1 is defined by the cutting path T1 (line segment EF of the control coordinate system) on the XY plane and the Z coordinate value Hz. Note that the control unit 60 calculates the first cutting path L1 from a plurality of position coordinates including two or more vertices in the outer shape of the opening surface 13g in the captured image CI. As the two or more vertices in the outer shape of the opening face 13g, any vertices may be used as long as the first cutting path L1 is obtained, and the calculation method may be appropriately selected.

  In FIG. 5, the calculation unit 62 sets a line segment AB connecting the vertices A and B and a line segment CD connecting the vertices C and D as a cutting path Ta2 on the xy plane of the two second tapes 18, respectively. Ask. Then, the arithmetic unit 62 converts the cutting path Ta2 on the xy plane from the image coordinate system to the camera coordinate system and further to the control coordinate system to obtain a cutting path T2 on the XY plane of the control coordinate system. As the coordinates of the cutting position (cutting height) in the Z direction, the coordinates Hz of the height position of the tape 17 detected by the height detecting device 30 are used. Therefore, the second cutting path L2 is defined by the cutting path T2 (the line segment AB and the line segment CD in the control coordinate system) on the XY plane and the Z coordinate value Hz.

  The second cutting path L2 can also be determined in consideration of the curvature of the edge line EL on the side edge of the opening surface 13g as shown in FIG. As shown in FIG. 6, a plurality of points are taken at an almost constant pitch on the edge line EL between the vertices AB, and the calculation unit 62 converts the xy coordinates of these point groups from the image coordinate system to the camera coordinate system, The coordinate is converted into the control coordinate system of the control, and the second cutting path L2 on the left side in FIG. 6 is obtained from the XY coordinates of the obtained point group in the control coordinate system and the Z coordinate value Hz. The arithmetic unit 62 converts the xy coordinates of the point group on the edge line EL between the vertices CD in FIG. 6 from the image coordinate system to the camera coordinate system and further to the control coordinate system, and obtains the obtained control coordinates. The second cutting path L2 on the right side in FIG. 6 is obtained from the XY coordinates of the point cloud of the system and the Z coordinate value Hz. Note that the method of calculating the cutting paths L1 and L2 using the coordinates of the outer shape of the opening surface 13g in the image coordinate system can be changed as appropriate.

  In step S16, the control unit 60 controls the robot 40 to control the position of the cutter 53 along the cutting paths L1 and L2 of the tapes 17 and 18, and cuts the tapes 17 and 18. That is, the control unit 60 controls the robot 40 to control the position of the cutter 53 of the cutter unit 51 fixed to the head 44 at the distal end of the arm 43 along the cutting paths L1 and L2 calculated in step S15, The tapes 17 and 18 are cut. More specifically, the control unit 60 moves the cutter 53 to the starting point of the first cutting path L1, controls the angle of the cutter 53 to a first posture angle when cutting the first tape 17, and moves the cutter 53 along the first cutting path L1. The first tape 17 is cut by moving to the end point while controlling the position. Accordingly, the cutter 53 moves along the cutting path L1 in FIG. 3 and cuts the first tape 17 along the boundary between the pair of flaps 16.

  Further, when cutting the second tape 18, the control unit 60 moves the cutter 53 to the starting point of the second cutting path L <b> 2 and moves the cutter 53 by a two-dot chain line in FIG. 2 when cutting the second tape 18. The angle is controlled to the second posture angle shown, and the robot is moved to the end point while controlling the position along the second cutting path L2, and the second tape 18 is cut. The second tape 18 is cut by the movement of the cutter 53 along the cutting path L2 in FIG.

  When the second cutting path L2 is obtained from the point group on the edge line EL shown in FIG. 6, the position of the cutter 53 is controlled as shown in FIG. As shown in FIG. 7, the cutter 53 first moves along the first cutting path L <b> 1 and cuts the first tape 17 as indicated by a dashed-dotted arrow (1) in FIG. 7. Next, the cutter 53 moves along the curved second cutting path L2 as shown by the dashed-dotted arrow (2) in FIG. 7, and cuts one of the second tapes 18. Further, the cutter 53 moves along the curved second cutting path L2 as shown by a dashed-dotted arrow (3) in FIG. 7, and cuts the other second tape 18. As shown in FIG. 7, even if the side surface 12B of the box 12 is curved, the second tape 18 is cut by the cutter 53 moving along the curve of the edge line EL of the unsealing surface 13. In the present embodiment, the processing in step S16 is based on the cutting height based on the height position of the opening surface and the cutting path of the tape geometrically determined from the outer shape of the opening surface 13g in the captured image CI. This corresponds to an example of a “control step” for controlling the position of the cutter 53 and cutting the tapes 17 and 18.

  For this reason, the cutter 53 moves along the cutting path L1 shown in FIG. 3 in a state where the cutter 53 is inserted into the first tape 17 at a predetermined depth. Therefore, even if the opening surface 13 is slightly deformed, the first tape 17 is reliably cut at the boundary between the pair of flaps 16. The cutter 53 does not excessively enter the box 12 while penetrating slightly deeper than the thickness of the first tape 17. For this reason, the first tape 17 can be reliably cut by the cutter 53 and the cutter 53 can be prevented from damaging the contents in the box 12. Further, as shown in FIG. 3, the two second tapes 18 pasted on the two side edges of the box 12 are cut by the cutter 53 moving along the second cutting path L2.

  As shown in FIG. 9A, the height detecting device 30 may be configured to be movable in the X direction in addition to the height direction Z, which is an intersecting direction intersecting the opening surface 13. In the example of FIG. 9A, the height detection device 30 includes a traveling platform 36 at the bottom, and the traveling platform 36 is guided by the rail 37 and moves in the X direction. The sensor unit 32 of the height detection device 30 emits detection light from the detection unit 33 toward the Y direction (the back side in the direction orthogonal to the paper surface in FIG. 9) from the position facing the side surface 12B of the box 12. The height detection device 30 is capable of moving up and down in the height direction Z by driving the motor 35 while emitting detection light in the Y direction from the detection unit 33 and driving the motor 38 disposed on the traveling platform 36. Can also be moved in the X direction. As illustrated in FIG. 9B, when the sensor unit 32 moves in the height direction Z while emitting the detection light from the detection unit 33 and detects the height position P as the height position of the first tape 17, Further, by moving in the height direction Z while moving in the X direction while emitting the detection light, the height position Q higher than the height position P of the first tape 17 can be detected. As shown in FIG. 9B, when the pair of flaps 16 are floating, the height position of the first tape 17 detected by the sensor unit 32 changes due to a slight difference in the X direction. Also, since the first tape 17 is very thin, if the height of the cutter 53 is slightly shifted, a cutting error of the first tape 17 occurs. However, in the height detecting device 30 shown in FIG. 9A, the sensor unit 32 emits the detection light in the Y direction, and is in the width direction of the first tape 17 in addition to the height direction Z (intersecting direction). Since the scanning can also be performed in the X direction, the highest position appropriate as the cutting position in the height direction Z of the first tape 17 can be detected more accurately. For this reason, as shown in FIG. 9B, even if the flap 16 is floating and inclined, the height position of the cutting path of the first tape 17 is properly detected and the first tape 17 is securely cut without mistake. Can be cut into

As described in detail above, according to the first embodiment, the following effects can be obtained.
(1) The box 12 is provided with an opening device 11 for opening the box 12 by cutting the attached tapes 17 and 18. The opening device 11 includes a height detection device 30 that detects the position of the tapes 17 and 18 in the height direction Z that intersects the opening surface 13 on which the tapes 17 and 18 of the box 12 are stuck. A camera 50 that captures an image from Z and obtains a captured image CI including the opening surface 13g. In addition, the opening device 11 includes a cutter 53 that moves relative to the box 12 and cuts the tapes 17 and 18. Further, the opening device 11 cuts the tapes 17 and 18 based on the positions in the height direction Z of the tapes 17 and 18 detected by the height detection device 30 and the position of the outer shape of the opening surface 13g in the captured image CI. The control unit 60 controls the position of the cutter 53 along L1 and L2 to cut the tapes 17 and 18. Therefore, the cutting paths L1 and L2 are determined based on the positions of the tapes 17 and 18 in the height direction Z intersecting the opening surface 13 and the position of the outer shape of the opening surface 13g in the captured image CI obtained by imaging the opening surface 13. Even if the positions of the tapes 17 and 18 vary somewhat in the height direction Z, the position of the cutter 53 with respect to the tapes 17 and 18 can be controlled appropriately. Therefore, it is possible to reduce unsuccessful opening of the box 12 due to a mistake in cutting the tapes 17 and 18 stuck on the opening surface 13 of the box 12.

  (2) The height detecting device 30 includes a sensor unit 32 that is movable in the height direction Z while emitting detection light in a direction parallel to the opening surface 13 with respect to the box 12, and the sensor unit 32 is connected to the height direction Z. And an elevating mechanism 31 for moving to The sensor unit 32 is moved in the height direction Z to detect the positions of the tapes 17 and 18 in the height direction Z. The elevating mechanism 31 as an example of the first moving mechanism and the robot 40 as an example of the second moving mechanism for moving the camera 50 to the imaging position are provided separately. Therefore, the position detection in the height direction Z of the tapes 17 and 18 and the imaging of the unsealing surface 13 can be performed in parallel by an independent moving mechanism. The cutting paths L1 and L2 of the cutter 53 are determined earlier, and the cutting work of the tapes 17 and 18 can be realized at a higher speed than in a configuration in which the height detection device 30 and the camera 50 are position-controlled by the same moving mechanism.

  (3) A first tape 17 affixed to the boundary between the two flaps 16 on the opening surface 13 of the box 12, a second tape 18 affixed along the boundary between the two flaps 16 and the side surface 12 </ b> B of the box 12. And are to be cut. The control unit 60 determines the first cutting path L1 of the first tape 17 from a plurality of position coordinates including two or more vertices in the outer shape of the opening surface 13g in the captured image CI, and along the determined first cutting path L1. The first tape 17 is cut by controlling the position of the cutter 53. In addition, the control unit 60 calculates an edge line EL that intersects the side surface 12B which is an adjacent surface in the opening surface 13 from the outer peripheral line of the opening surface 13g in the captured image CI of the camera 50, and along the determined edge line EL. The position of the cutter 53 is controlled along the second cutting path L2 to cut the second tape 18. Accordingly, since the position of the cutter 53 is controlled in the second cutting path L2 along the edge line where the opening surface 13 and the side surface 12B of the box 12 intersect, even if the side surface 12B of the box 12 is deformed, the bending is caused by the deformation. The second tape 18 can be cut along the formed edge line.

  (4) The box 12 is opened by cutting off the tapes 17 and 18 applied along the periphery of the flap 16 that closes the opening 12K of the box 12. A position detecting step (S11) for detecting the positions of the tapes 17 and 18 in the height direction Z intersecting with the unsealing surface 13 where the tapes 17 and 18 of the box 12 are stuck, and imaging the unsealing surface 13 of the box 12 An imaging step (S12, S13) for acquiring an image CI. Cutting paths L1 and L2 of the tapes 17 and 18 determined based on the positions in the height direction Z of the tapes 17 and 18 detected by the position detection step and the position of the outer shape of the opening surface 13g in the captured image CI acquired in the imaging step. (S15, S16) for controlling the position of the cutter 53 along the line and cutting the tapes 17, 18. Therefore, similarly to the unsealing device 11, unsuccessful opening of the box 12 due to a mistake in cutting the tapes 17 and 18 can be reduced.

  (5) By the way, when the image of the tape 17 can be recognized from the captured image CI, a method of cutting along the width center line of the first tape 17 can be considered. However, if the width center of the first tape 17 is shifted in the width direction from the boundary between the two flaps 16, the flaps 16 are cut and the box 12 cannot be opened. In the present embodiment, since the first cutting path L1 is determined from the outer shape of the opening surface 13g in the captured image CI, the first tape 17 can be cut along the boundary between the pair of flaps 16. Therefore, the first tape 17 is cut along the border of the flap 16, and the unsealing mistake of the box 12 can be further reduced.

(2nd Embodiment)
Next, a second embodiment will be described with reference to FIGS. 1, 10, and 11. FIG. In this embodiment, the height detecting device 30 is not provided.

  As shown in FIG. 1, a head 44 attached to the distal end of the arm 43 of the robot 40 has a camera 50 and a cutter unit 51, and is indicated by a two-dot chain line in FIG. A distance sensor 55 is provided. The distance sensor 55 measures the distance to the opening surface 13 in order to obtain the height position of the opening surface 13 instead of the height detection device 30 in the first embodiment. As shown in FIG. 10, the distance sensor 55 is attached to the support 49 of the head 44 such that the angle can be changed. When the cutter 53 is in the posture at the time of cutting, it faces the unsealing surface 13 of the box 12 and the distance LZ to the unsealing surface 13 can be measured. For example, the distance sensor 55 is provided so as to be disposed at a position ahead of the traveling direction when the cutter 53 cuts the tapes 17 and 18 in the support portion 49. During the movement of the cutter 53 for cutting the tapes 17 and 18, the distance LZ is measured at a position on the opening surface 13 where the cutter 53 reaches after a predetermined time elapses and becomes a cutting position. In a state where the head 44 is inclined to the posture when the cutter 53 cuts the tapes 17 and 18, the distance sensor 55 is disposed at a position where the detection light HL is directed in the height direction Z and faces the unsealing surface 13.

  As shown in FIG. 1, when the camera 50 captures an image of the opening surface 13 from the imaging position, the distance sensor 55 measures the distance to the opening surface 13 and determines the height position Hz of the opening surface 13 from the measured distance. To detect. That is, the distance sensor 55 detects the height position Hz of the opening surface 13 of the box 12 instead of the height detection device 30 in the first embodiment.

Further, the control unit 60 controls the position of the cutter 53 in the height direction Z according to a change in the distance LZ to the opening surface 13 detected by the distance sensor 55.
The program PR shown in the flowchart of FIG. 11 is stored in the memory 63 of the control unit 60. The computer in the control unit 60 controls the disconnection of the opening device 11 by executing the program PR shown in FIG. Hereinafter, the cutting control of the opening device 11 performed by the control unit 60 executing the program PR shown in FIG. 11 will be described.

  First, in step S21, the control unit 60 moves the camera 50 to the imaging position. That is, the control unit 60 controls the robot 40 to move the camera 50 to an imaging position, which is a position above the opening surface 13. The imaging position may be a fixed position. For example, the height of the box 12 is obtained from the box identification information, and the position above the height position of the opening surface 13 of the box 12 by the focal length of the camera 50 is set as the imaging position. The camera 50 may be moved to this imaging position. Further, based on the distance to the opening surface 13 measured by the distance sensor 55, the moving distance from the camera 50 to the position at which the distance from the opening surface 13 becomes the focal length is obtained, and the camera 50 is moved by the moving distance. It may be arranged at the imaging position.

  In step S22, the control unit 60 causes the camera 50 to image the opening surface 13 of the box 12. Image data CI obtained by capturing the opening surface 13 by the camera 50 is sent to the control unit 60. In the present embodiment, the process in step S22 corresponds to an example of an “imaging step” in which the opening surface 13 of the box 12 is imaged to acquire the captured image CI.

  In step S23, the control unit 60 measures the distance to the tapes 17 and 18 attached to the opening surface 13 of the box 12 with the distance sensor 55. As shown in FIG. 1, when the camera 50 is at the imaging position when imaging the opening surface 13, the distance sensor 55 measures the distance Hs to the tapes 17 and 18 attached to the opening surface 13. Since the distance ΔH in the height direction between the camera 50 and the distance sensor 55 is known, the distance Ha (= Hs−ΔH) from the camera 50 to the opening surface 13 to which the tapes 17 and 18 are attached can be calculated. In the example of FIG. 1, since the opening surface 13 is the top surface of the box 12, the imaging position of the camera 50 is right above the opening surface 13. On the other hand, for example, when the opening surface 13 is in the horizontal direction, the control unit 60 controls the robot 40 to set the head 44 in the horizontal direction facing the opening surface 13, and captures an image of the horizontal opening surface 13 with the camera 50 from right beside. At the same time, the distance sensor 55 may measure the distance to the opening surface 13.

  In step S24, the control unit 60 performs image processing on the image CI including the opening surface 13g. The control unit 60 performs, for example, a binarization process on the image CI including the opening surface 13g, and acquires an image CI in which the outer shape of the opening surface 13g can be easily grasped.

  In step S25, the control unit 60 calculates the cutting paths of the tapes 17 and 18. More specifically, the control unit 60 obtains the distance Ha from the camera 50 to the tapes 17 and 18 attached to the opening surface 13 of the box 12 using the distance Hs measured by the distance sensor 55, and will be described with reference to FIGS. As described above, the first cutting path L1 shown in FIG. 5 and the second cutting path L2 shown in FIG. 5 or FIG. 6 are obtained by geometric calculation from the outer shape of the opening face 13g after the image processing.

In step S26, the control unit 60 cuts the tapes 17 and 18 while controlling the height of the cutter 53 according to the detection distance of the distance sensor 55.
As shown in FIG. 10, the control unit 60 cuts the first tape 17 by moving the cutter 53 while controlling the position thereof along the first cutting path L1 under the control of the robot 40, and cuts the cutter 53 in this moving process. The distance sensor 55 measures the distance LZ to the first tape 17 in the height direction Z (intersecting direction) at the position ahead of the traveling direction. The control unit 60 controls the position of the cutter 53 in the height direction (intersecting direction) according to a change in the distance LZ to the first tape 17 measured by the distance sensor 55 at a position ahead of the cutter 53 in the traveling direction. As a result, as shown in FIG. 10, even if the opening surface 13 of the box 12 is curved, such as concave, the height of the cutter 53 is controlled according to the surface shape of the curved first tape 17, so that The first tape 17 stuck on the opened surface 13 can also be appropriately cut. Similarly, the second tape 18 is cut while controlling the height of the cutter 53 in accordance with the detection distance of the distance sensor 55. Even if the unsealing surface 13 of the box 12 is curved, such as being concave, the second tape 18 can be cut by the cutter 53 following the curved surface shape of the second tape 18. Further, even if the side surface 12B of the box 12 is deformed and the edge line EL of the side edge of the unsealing surface 13 is curved, the position of the cutter 53 is controlled by following the curved edge line EL so that the second tape 18 can be secured. And the cutter 53 can be prevented from damaging the contents in the box 12.

As described above, according to the second embodiment, the following effects can be obtained.
(6) The position detector is a distance sensor 55 that measures the distance to the tapes 17 and 18 in the height direction Z and detects the positions of the tapes 17 and 18 in the height direction Z. The control unit 60 causes the distance sensor 55 to detect the distance to the surface on which the tapes 17 and 18 are attached, and controls the position of the cutter 53 in the height direction Z according to the change in the distance to the tapes 17 and 18. Therefore, the tapes 17 and 18 can be cut following the depression of the opening surface 13 in the box 12.

  (7) The method of opening the box 12 is to cut the tapes 17 and 18 attached along the periphery of the flap 16 that closes the opening 12K of the box 12 and open the box 12. A position detecting step (S23) for detecting the positions of the tapes 17 and 18 in the height direction Z intersecting the opening surface 13 where the tapes 17 and 18 of the box 12 are stuck, and an imaging step for imaging the opening surface 13 of the box 12 (S21, S22). The cutters are cut along the cutting paths L1 and L2 of the tapes 17 and 18 determined by the positions in the height direction Z of the tapes 17 and 18 detected by the position detection step and the outer shape of the unsealing surface 13 in the captured image CI acquired by the imaging step. A control step (S25, S26) of cutting the tapes 17 and 18 by controlling the position of the tape 53. Therefore, similarly to the opening device 11, defective opening of the box 12 due to a mistake in cutting the tapes 17 and 18 can be reduced.

(Third embodiment)
Next, a third embodiment will be described with reference to FIGS. In this embodiment, similarly to the second embodiment, the robot 40 includes a distance sensor 55 as an example of a position detection unit, and the camera 50 as an example of an imaging unit is fixed at a predetermined height and located below. The opening surface 13 of the box 12 is imaged.

  As shown in FIGS. 12 and 13, the opening device 11 for the box 12 includes an articulated robot 40 as in the first and second embodiments. The robot 40 has arm portions 43A, 43C, and 43D constituting the arm 43, as in the first embodiment. In the robot, for example, a six-axis or seven-axis head 44 is detachably mounted to the arm 43D. The head 44 is supported by a rotating part 48 that is rotatable at the distal end of an arm 43 by using a motor (not shown) as a power source.

  The box opening system 10 shown in FIG. 12 includes a carry-in conveyor 81 that carries the box 12 into the opening device 11 and a carry-out conveyor 82 that carries out the box 12 after opening from the opening device 11. The opening device 11 of the present embodiment includes an elevating conveyor 83 as an example of a transport mechanism. The elevating conveyor 83 is disposed between the carry-in conveyor 81 and the carry-out conveyor 82. The carry-in conveyor 81 and the carry-out conveyor 82 are arranged at the same height, and are, for example, a roller conveyor having a plurality of rollers 81A and 82A, respectively. The opening device 11 receives the unopened box 12 carried from the carry-in conveyor 81 onto the conveyor 83, and transfers the opened box 12 opened by the robot 40 to the carry-out conveyor 82.

  As shown in FIGS. 12 and 13, the conveyor 83 is, for example, a belt conveyor. The conveyor 83 includes a pair of rollers 84, a support base 83A that supports the rollers 84, a transport belt 85 wound around the pair of rollers 84, and a motor 83M that drives one of the rollers 84. The opening device 11 includes a control unit 60 (see FIG. 4) substantially the same as that of the first embodiment. When the control unit 60 drives the motor 83M to rotate forward, the conveyor 83 is driven in a direction to transport the box 12 in the first direction X1, and when the control unit 60 drives the motor 83M to rotate in the reverse direction, the conveyor 83 It is driven in a direction in which it is transported in a second direction X2, which is a direction opposite to the first direction X1.

  In the present embodiment, the stop of the loaded box 12 at the work position is performed by stopping the driving of the conveyor 83. The conveyor 83 is provided with a plurality of first sensors 29 that detect the box 12 that has reached the work position SP on the conveyor belt 85 at positions on both sides of the conveyor belt 85 in the width direction. The plurality of first sensors 29 detect boxes 12 of different sizes, and can stop the boxes 12 of any size at a predetermined work position on the transport belt 85. In this embodiment, the box 12 may be transported in the second direction X2 in the process of the robot 40 cutting the tapes 17 and 18, and in this case, the box 12 transported in the second direction X2 is stopped by a predetermined stop. The conveyor 83 is provided with a second sensor 72 capable of detecting the box 12 to stop at the position. The first sensor 29 and the second sensor 72 are, for example, optical sensors. The optical sensor includes a light emitter and a light receiver, and detects the box 12 by blocking light from the light emitter to the light receiver. Note that the first sensor 29 and the second sensor 72 may be non-contact sensors other than optical sensors or contact sensors.

  The assembly 110 that surrounds the elevating mechanism 86 and the robot 40 includes a plurality of pillars 111 and a beam 112 that is suspended between upper ends of the pillars 111. A camera 50 as an example of an imaging unit is fixed to one beam 112 extending in the transport direction X at a position directly above a central portion of the upper surface of the transport belt 85 by a predetermined distance. The camera 50 captures an image of the opening surface 13 of the box 12 placed at the work position SP on the conveyor 83 from a height position separated by a predetermined distance in the cross direction.

  Further, an assembly 120 that supports the robot 40 is disposed inside the assembly 110. The assembly 120 includes a plurality of pillars 121, a plurality of beams 122 laid between the pillars 121, and a support plate 123 laid between the pillars 121 at a predetermined height. The robot 40 is installed on the support plate 123.

  The elevating conveyor 83 is at a standby position H0 (down position) indicated by a two-dot chain line in FIG. 12 when the box 12 is loaded and unloaded, and when the robot 40 opens the box 12, the standby position H0 is set. To the working height position H1 indicated by the solid line in FIG. FIG. 12 shows the working height position H1 of the conveyor 83 when the box 12 is the maximum size. The robot 40 performs an opening operation in which the tapes 17 and 18 attached to the opening surface 13 of the box 12 are cut by the cutter unit 51 attached to the head 44.

  As shown in FIGS. 12 and 13, the opening device 11 includes an elevating mechanism 86 that elevates and lowers the box 12 together with the conveyor 83. The lifting mechanism 86 includes a conveyor 83 and a lifting unit 87. The elevating unit 87 includes a pair of guide rods 88, a pair of elevating sliders 89 movable along the pair of guide rods 88, and a support table 90 fixed to the pair of sliders 89. The conveyor 83 is supported on a support table 90 via a plurality of support rods 91.

  As shown in FIGS. 12 and 13, the elevating unit 87 converts the elevating motor 92 serving as a driving source and the rotational power of the motor 92 into a linear motion in the vertical direction Z for elevating the conveyor 83. And a power transmission mechanism 93. The power transmission mechanism 93 is, for example, a belt-type power transmission mechanism. The power transmission mechanism 93 includes a drive belt 97 wound around a pulley 94 fitted on the output shaft of the motor 92, a pulley 96 fitted on the rotating shaft 95, and a rotating shaft common to the pulley 96. A timing belt 100 is wound around a pulley 98 fitted on the pulley 95 and a pulley 99 located above the pulley 98 at a predetermined distance in the vertical direction Z with respect to the pulley 98. The rotating shaft 95 is supported rotatably in a horizontal state at a lower position near the bottom plate where the guide rod 88 is erected. Two pairs of pulleys 98 and 99 are provided in pairs at the top and bottom, and the two timing belts 100 wound around the two pairs of pulleys 98 and 99 extend vertically at predetermined intervals in the transport direction X. The motor 92 is, for example, a servomotor.

  A part of the two timing belts 100 is fixed to the support table 90. When the control unit 60 drives the motor 92 to rotate forward, the conveyor 83 moves up, and when the control unit 60 drives the motor 92 to rotate backward, the conveyor 83 moves down. A flexible cable 101 for guiding a power line and a signal line for supplying electric power to the motor 83 </ b> M provided on the conveyor 83 and the sensors 29 and 72 and the like is provided in a state of hanging from the support table 90. The power transmission mechanism 93 is not limited to the belt-type power transmission mechanism, and may be another type.

  The elevating mechanism 86 moves the conveyor 83 up and down to adjust the height position of the box 12, thereby disposing the opening surface 13 of the box 12 at the focal position of the camera 50. That is, by controlling the motor 92, the opening surface 13 can be arranged at the focal position regardless of the size of the box 12 of any size. The elevating mechanism 86 includes a height sensor (not shown) that detects that the opening surface 13 of the box 12 has reached the working height position H1 that is the focal position of the camera 50. When the height sensor detects the opening surface 13 of the box 12, the control unit 60 stops driving the motor 92. The control unit 60 obtains the height of the box 12 from the box specifying information received from the control system on the upstream side, and controls the motor 92 by a driving amount corresponding to the height, thereby obtaining the opening surface 13. May be controlled to raise the conveyor 83 until the camera reaches the focal position of the camera 50.

  In FIG. 13, an alternate long and short dash line indicates an operation range WS of the robot 40. The operation range WS of the robot 40 is a P-point operation range when the rotation center of the bending axis of the wrist in the arm 43 of the robot 40 is set to the P point. If the cutting path (cutting line) of the box 12 to be worked is within the operating range WS, the cutting of the tapes 17 and 18 along the cutting path is guaranteed regardless of the posture of the robot 40 at the time of cutting. .

  As shown in FIG. 13, the operation range WS has an arc-like shape in which the width in the width direction Y when viewed from the transport direction X is narrow between the upper position and the lower position of the operation range WS and wide at the height therebetween. Draw a line. At a height near the base end of the arm 43A corresponding to the upper arm of the arms 43, the operating range WS becomes the largest in the width direction Y. The lower the distance from the height near the base end of the arm portion 43A, the narrower the operating range WS is in the width direction Y, and at a position below a predetermined position below the installation surface of the robot 40 by a predetermined distance, Departs from the operating range WS. If the position of the conveyor 83 at the time of performing the tape cutting operation is the standby position H0, the opening surface 13 of the box 12 of the maximum size is arranged in a relatively wide area within the operation range WS. However, on the opening surface 13 of the box 12 having the minimum size, a portion outside the operating range WS occurs. That is, there is a possibility that the tapes 17 and 18 cannot be cut in the box 12 having the minimum size.

  When the robot 40 performs the tape cutting operation, the head 44 takes a posture hanging down from the tip of the arm 43 or a posture in which it is lowered at a predetermined angle. Taking into account the length of the head 44 in the vertical direction Z when taking this cutting posture, the box 12 is set so that the arm 43 can perform the tape cutting operation using the cutter 53 at the height position where the operation range WS is the widest. The working height HF is set. The working height HF at which the unsealing surface 13 is arranged is set to a height at which the operating range WS of the arm 43 can be as wide as possible when the cutter 53 is at that height. That is, the height of the opening surface 13 at the time of the tape cutting operation is set to a height that is lower than the height at which the operation range WS of the arm 43 can be ensured the widest by the height of the head 44. .

  Here, the working height HF indicates a height position where the opening surface 13 to which the tapes 17 and 18 are attached is located. The conveyor 83 is raised by the lifting mechanism 86 from the standby position H0 until the opening surface 13 of the box 12 reaches the working height HF. For this reason, the height of the conveyor 83 is adjusted by the elevating mechanism 86 such that the opening surface 13 of the box 12 of any size from the minimum size to the maximum size is always located at the working height HF.

  The camera 50 is fixed at a height position where the opening surface 13 located at the working height HF in the box 12 is the focal point. That is, when the box 12 is at the working height HF, the camera 50 is fixed at a height position where the distance between the camera 50 and the opening surface 13 is the focal length. Therefore, the camera 50 captures a clear and focused image including the entire opening surface 13 when the box 12 is viewed from almost right above.

  The imaging position of the camera 50 is set at a position above the opening surface 13 by a predetermined height in a cross direction (vertical direction Z) orthogonal to the opening surface 13 at the working height HF. The camera 50 acquires a captured image including the opening surface 13. Image data captured by the camera 50 is transmitted to the control unit 60 (see FIG. 4).

  The opening device 11 includes a control unit 60 having the configuration shown in FIG. 4 as in the first embodiment. However, in the third embodiment, an elevation type conveyor 83 is electrically connected to the control unit 60 instead of the conveyor 21 in FIG. 4, and the height detection device 30 is used to detect the height position of the opening surface 13. , The distance sensor 55 is electrically connected. Further, in the third embodiment, the sensor 29 electrically connected to the control unit 60 controls the positioning of the box 12 to the working position by controlling the stop of the conveyor 83. Provided. When one sensor 29 corresponding to the size of the box 12 determined from the box specifying information among the plurality of sensors 29 detects the box 12 and turns on, the control unit 60 stops the conveyor 83, thereby causing the conveyor 12 to stop. Stop at the upper working position SP. In a state where the box 12 is in the working position SP, for example, the optical axis of the camera 50 matches the center of the opening surface 13.

  The control unit 60 has received the box specifying information from the depalletizer in advance. The control unit 60 controls the elevating unit 87 based on the information on the size and the height dimension of the box 12 obtained based on the box specifying information, raises the conveyor 83 from the standby position H0, and controls the box 12 on the conveyor 83. Is raised to a position where the opening surface 13 reaches the working height HF. For this reason, the box 12 of the maximum size is placed at a position where the conveyor 83 rises from the standby position H0 shown by a two-dot chain line in FIG. 12, and the opening surface 13 reaches the working height HF as shown in FIGS. Is done. In the minimum-size box 12, the conveyor 83 rises from the standby position H0 indicated by a two-dot chain line in FIG. 14 to a working height position H2 corresponding to the height of the minimum-size box 12, and is indicated by a solid line in FIG. The opening surface 13 of the box 12 shown is arranged at a position reaching the working height HF.

Next, the head 44 will be described with reference to FIGS.
As shown in FIGS. 15 and 16, the head 44 is detachably attached to the rotating unit 48 of the robot 40 as in the first embodiment. The head 44 includes a support portion 49, a cutter unit 51, a distance sensor 55, and a roller 56 as an example of a pair of rolling elements. The cutter unit 51, the distance sensor 55, and the pair of rollers 56 are assembled to the support 49, respectively. The support portion 49 is configured such that a base end, which is an end opposite to the cutter 53 in the longitudinal direction, can be attached to the rotating portion 48.

  As shown in FIGS. 15 and 16, the cutter unit 51 has the same configuration as that of the first embodiment, and is detachably fixed to a columnar vibrator 52 and a distal end portion of an output shaft of the vibrator 52. And a cutter 53 provided. The columnar vibrator 52 is fixed to the bottom portion 49A of the columnar vibrator 52 via a connecting member 57 by fastening using a bolt (not shown) in a state housed in the concave portion of the support portion 49. A power line 52A extending from the base end of the cutter unit 51 is electrically connected to an oscillator (not shown), and the vibrator 52 applies ultrasonic vibration to an output shaft by a periodically changing voltage supplied from the oscillator through the power line 52A. This causes the cutter 53 fixed to the output shaft to ultrasonically vibrate.

  As shown in FIGS. 15 and 16, the distance sensor 55 is mounted on the support 49 at the opposite surface of the bottom 49A where the cutter unit 51 is mounted. The distance sensor 55 outputs an output wave OW such as an electromagnetic wave (including light) or a sound wave toward the distal end where the cutter 53 is located, detects the reflected wave as an electric signal, and thereby detects the distance to the reflecting surface. Is measured. As long as the distance sensor 55 can detect the distance, the detection method can be appropriately selected.

  The pair of rollers 56 shown in FIGS. 15 and 16 are disposed at both sides of the cutter 53 in the moving direction when the cutter 53 cuts the tapes 17 and 18, and are positioned at the bottom of the support 49. It is pivoted on. The distal end of the cutter 53 protrudes by a predetermined amount to the distal end side from a common tangent at a portion where the pair of rollers 56 comes into contact when rolling on the box 12. The predetermined amount corresponds to a cutting depth when the cutter 53 cuts the tapes 17 and 18. When the robot 40 cuts the tapes 17 and 18, the pair of rollers 56 rolls on the tapes 17 and 18, so that the cutting depth of the cutter 53 into the tapes 17 and 18 becomes substantially constant. Do not damage the contents. Further, even if the opening surface 13 of the box 12 is curved due to a dent or the like, the cutting depth of the cutter 53 becomes substantially constant by rolling the pair of rollers 56 along the curved surface. For this reason, the occurrence of a portion that cannot be cut into the tapes 17 and 18 due to the insufficient cutting depth of the cutter 53 is avoided.

Next, the operation of the box opening device 11 will be described.
Boxes 12 of various heights from the minimum size to the maximum size are carried from the carry-in conveyor 81 to the conveyor 83 at the standby position H0. The control unit 60 acquires information on the size and height of the box 12 based on the box identification information acquired in advance. The conveyor 83 conveys the box 12 received from the carry-in conveyor 81 in the first direction X1. When one first sensor 29 corresponding to the size of the box 12 to which the conveyor 83 is transported detects the box 12, the control unit 60 stops driving the conveyor 83. As a result, the box 12 stops at the work position SP on the conveyor 83.

Hereinafter, the control unit 60 controls the opening device 11 according to the flowchart shown in FIG. 20, and performs opening control for cutting the tapes 17 and 18 attached to the box 12 and opening the box 12.
First, in step S31, the control unit 60 moves the box 12 to the focal position of the camera 50. The control unit 60 drives the motor 92 to rotate in the normal direction to raise the conveyor 83. The control unit 60 stops driving the motor 92 when the height sensor detects the box 12. Thereby, the opening surface 13 of the box 12 is arranged at the working height HF located at the focal position of the camera 50.

The following steps S32 to S34 are the same as the processing of steps S13 to S15 in FIG. 8 in the first embodiment.
In step S32, the control unit 60 causes the camera 50 to capture an image of the opening surface 13 of the box 12. The camera 50 acquires an image CI (see FIG. 5) including the opening surface 13g. The control unit 60 acquires the image CI captured by the camera 50. When the camera 50 captures an image, the robot 40 has retracted the arm 43 to a standby position that does not interfere with the imaging of the box 12. The robot 40 stands by, for example, with the arm 43 facing either the upstream or the downstream in the transport direction X with respect to the front.

  In step S33, the control unit 60 performs image processing on the image including the opening surface 13g. The control unit 60 performs, for example, binarization processing as image processing on the image CI including the opening surface 13g, and generates an image in which the outer shape of the opening surface 13g can be easily grasped. Note that the image processing may be omitted as long as the outer shape of the opening surface 13g can be grasped.

  In step S34, the control unit 60 calculates a cutting path on the opening surface 13. The control unit 60 acquires the coordinates of the four points A to D, which are the vertices of the square, which is the outer shape of the opening surface 13g, in the image CI after the image processing illustrated in FIG. The two points in the longitudinal direction of the four points A to D, that is, the midpoints E and F of the points A and B and the points C and D, respectively, are obtained. Is determined as the measurement path. The control unit 60 uses the image system coordinates of the measurement path of the first tape 17 (hereinafter, also referred to as “first measurement path”), the focal length between the camera 50 and the opening surface 13, and the like, 1. One measurement path is obtained by XYZ coordinates of the control coordinate system. In addition, the control unit 60 sets the left and right two points each, that is, a line connecting the points A and B and the points C and D as a measurement path of the second tape 18 (hereinafter, also referred to as a “second measurement path”). Ask. The control unit 60 acquires the second measurement path in the XYZ coordinates of the control coordinate system using the image system coordinates of the second measurement path, the focal length between the camera 50 and the opening surface 13, and the like. In each control system coordinate of the first measurement path and the second measurement path, the Z coordinate value is a constant value.

  In step S35, the control unit 60 determines whether or not the cutting path L1 is within the operation range WS of the robot 40. The controller 60 stores, in the memory 63, table data in which information as to whether or not the cutting path of the box 12 is within the operation range WS of the robot 40 and the box size are associated. The control unit 60 determines whether or not the cutting path L1 is within the operation range WS by referring to the table data based on the box size information of the target box 12 at that time. The control unit 60 proceeds to step S36 if the cutting path L1 is within the operating range WS, and proceeds to step S37 if the cutting path L1 is not within the operating range WS.

  Here, in the present embodiment, with respect to the first cutting path L1, it is determined that the box 12 at the work position SP has all sizes and the cutting path is within the operation range WS of the robot 40. In addition, as for the second cutting path L2, for the box 12 belonging to the small size included in the range equal to or larger than the minimum size and smaller than the predetermined threshold size, it is determined that the second cutting path is within the operation range WS of the robot 40. . Further, it is determined that the box 12 belonging to the large size included in the range equal to or larger than the predetermined threshold size and equal to or smaller than the maximum size does not have the second cutting path L2 within the operation range WS of the robot 40. As described above, the control of cutting the tapes 17 and 18 is different between the box 12 belonging to the large size and the box 12 belonging to the small size. When the first cutting path L1 is within the operation range WS of the robot 40 in all box sizes, the determination processing in step S35 can be omitted for the first cutting path L1.

<Cut the tape in a large box>
Hereinafter, an example of the box 12 belonging to the large size will be described first. Since the first cutting path L1 of the largest-sized box 12 is within the operation range WS of the robot 40, the control unit 60 proceeds to step S36.

  In step S36, the control unit 60 measures the distance to the tape 17 with the distance sensor 55 along the cutting path. The control unit 60 drives the arm 43 of the robot 40, and holds the head 44 upright while keeping the distance sensor 55 at a height position (coordinate Z1) separated from the opening surface 13 by a predetermined distance as shown in FIG. By setting the posture, the distance sensor 55 is arranged so that the cutting path L1 (see FIGS. 3 and 7) on the opening surface 13 can be directed to the measurement target. The control unit 60 moves the head 44 in the vertical posture along the first measurement path (XY coordinates). In this movement process, the distance sensor 55 measures the distance LZ in the vertical direction Z to the first tape 17 at a plurality of points along the cutting path L1. The distance LZ of the plurality of points in the vertical direction Z indicates a change in the position of the first cutting path L1 in the vertical direction Z. The control unit 60 stores information on the first measurement path (XY coordinates), the position coordinate Z1 in the vertical direction Z at the time of measurement by the distance sensor 55, and the distance LZ in the vertical direction Z of a plurality of points, which is the measurement result of the distance sensor 55. Based on the above, a cutting path (XYZ coordinates) represented by the control system coordinates of the first tape 17 is obtained. The control system coordinates (XYZ coordinates) of this cutting path reflect changes in the position of the cutting path of the first tape 17 in the vertical direction Z. After finishing the measurement by the distance sensor 55, the control unit 60 proceeds to the next step S38.

  In step S38, the control unit 60 cuts the tape 17 while controlling the height of the cutter 53 according to the detection distance of the distance sensor 55. That is, the control unit 60 controls the position of the cutter 53 along the cutting path (XYZ coordinates) of the first tape 17 represented by the control system coordinates. At this time, the position of the cutter 53 is also controlled in the vertical direction Z during the cutting process of the first tape 17.

  As shown in FIG. 18, even when the opening surface 13 of the box 12 is concave and the first tape 17 is curved, the position of the cutter 53 is controlled in the vertical direction Z. It moves along the cutting path on the curved first tape 17 along the path indicated by the dashed line arrow. As a result, the cutting depth required for the cutter 53 is secured over the entire area of the first tape 17 in the longitudinal direction, and the first tape 17 is reliably cut.

  When the first cutting path is not within the operation range WS, the control unit 60 measures the distance to the tape 17 with the distance sensor 55 along the cutting path in step S37 with the transport operation of the box 12. . Then, after the measurement by the distance sensor 55 is completed in step S37, the process proceeds to the next step S39. In step S39, the control unit 60 cuts the tape 17 while controlling the height of the cutter 53 in accordance with the detection distance of the distance sensor 55 with the transport operation of the box 12. For example, when even a part of the first cutting path of the large-sized box 12 is not within the operation range WS, the first tape 17 is cut by any one of the following three methods. First, the box 12 is transported on the conveyor 83 in the transport direction X, and the first tape 17 is cut into two parts in the longitudinal direction at different positions before and after the transport, and the first tape 17 is cut by two. Cut in several times. Second, the first tape 17 is cut by controlling the position of the cutter 53 in the width direction Y and the vertical direction Z while transporting the box 12 at a constant speed. Third, while the box 12 is being conveyed at a constant speed, the cutter 53 is moved in the direction opposite to the conveying direction of the box 12 based on the XY coordinates of the first cutting path, and the cutter 53 is position-controlled in the vertical direction Z. Then, the first tape 17 is cut. In step S36, the measurement by the distance sensor 55 is performed by the above three methods.

  In step S40, the control unit 60 determines whether the box 12 has been opened. When the first tape 17 has been cut, the box 12 has not been opened since the second tape 18 has not yet been cut. Therefore, the control unit 60 proceeds to the process of step S41.

  In step S41, the control unit 60 switches to the next cutting path. In this example, when the cutting of the first tape 17 is completed, the cutting path is switched to the cutting path of one of the two second tapes 18 to be cut first. After switching the cutting path, the control unit 60 returns to the process of step S35. In this way, the control unit 60 repeatedly executes the processing of steps S35 to S39 for each cutting path until the opening of the box 12 is completed in step S40. In this example, since the tape is H-attached and has three cutting paths for cutting the three tapes 17 and 18, the control unit 60 repeats the processing of steps S35 to S39 three times.

In the large-size box 12, a part of the opening surface 13 protrudes outside the operating range WS at the work position SP on the conveyor 83.
In step S35, the control unit 60 determines whether or not one of the cutting paths L2 is within the operation range WS of the robot 40. The control unit 60 determines whether or not one of the cutting paths L2 is within the operation range WS by referring to the table data based on the box size information of the target box 12 at that time. If it is a large-sized box 12, the control unit 60 proceeds to step S37 to determine that one of the cutting paths L2 is not within the operation range WS.

  In step S37, the control unit 60 measures the distance to one of the second tapes 18 by the distance sensor 55 along the cutting path L2 with the transport operation of the box 12. First, the control unit 60 drives the conveyor 83 to move the box 12 in the transport direction X until one of the second cutting paths L2 enters the operation range WS of the robot 40. In this example, the box 12 is moved from the work position SP in the second direction X2. As a result, the box 12 is placed at the first transport position shown by the solid line in FIG. At the first transport position, the second tape 18 on the right side of the box 12 in FIG. Then, the control unit 60 drives the arm 43 of the robot 40 to bring the head 44 into the vertical position while keeping the distance sensor 55 at a height position (coordinate Z1) separated from the opening surface 13 by a predetermined distance. The distance sensor 55 is arranged in a direction in which the cutting path L2 on the opening surface 13 (see FIGS. 3 and 7) can be directed as a measurement target. The control unit 60 moves the head 44 in the upright posture along the second measurement path (XY coordinates) in the width direction Y different from the traveling direction in FIG.

  During this movement process, the distance sensor 55 measures the distance LZ in the vertical direction Z to the second tape 18 at a plurality of points along the cutting path L2. The distance LZ of the plurality of points in the vertical direction Z indicates a change in the position of the second cutting path L2 in the vertical direction Z. The control unit 60 stores information on the second measurement path (XY coordinates), the position coordinate Z1 in the vertical direction Z at the time of measurement by the distance sensor 55, and the distance LZ in the vertical direction Z of a plurality of points, which is the measurement result of the distance sensor 55. Then, a cutting path (XYZ coordinates) represented by the control system coordinates of the second tape 18 is obtained based on the above. The control system coordinates (XYZ coordinates) of the cutting path reflect changes in the position of the second tape 18 in the vertical direction Z. In addition, it is preferable that the second measurement path is measured along a position that allows a predetermined margin inside the edge of the box 12. As a result, even if the box 12 is deformed, the opening surface 13 of the box 12 can be measured unless the box 12 is deformed excessively.

  In the next step S39, the control unit 60 cuts one of the second tapes 18 while controlling the height of the cutter 53 according to the detection distance of the distance sensor 55 in conjunction with the transport operation of the box 12. That is, the control unit 60 controls the position of the cutter 53 along the cutting path (XYZ coordinates) of the one second tape 18 represented by the control system coordinates. At this time, the position of the cutter 53 is also controlled in the vertical direction Z during the cutting process of the second tape 18. In this step S39 for the second cutting path, the carrying operation is performed in the previous step S37, and the carrying operation is omitted because the entire second cutting path is already within the operation range WS of the robot 40.

  The position of the head 44 indicated by a solid line in FIG. 19 is controlled along a cutting path L2 represented by control system coordinates in a posture obliquely inclined with respect to one of the second tapes 18. At this time, even if the second tape 18 is curved because the opening surface 13 of the box 12 is concave, since the position of the cutter 53 is controlled in the vertical direction Z, the cutter 53 is placed on the curved second tape 18. Along the cutting path L2. As a result, the cutting depth necessary for the cutter 53 is secured in the entire area in the longitudinal direction of the second tape 18, and the second tape 18 is reliably cut.

  In step S40, the control unit 60 switches to the next cutting path in step S41 to determine that the box 12 has not been opened. That is, switching to the cutting path L2 of the other second tape 18 is performed. Then, control unit 60 returns to the process of step S35.

  In step S35, the control unit 60 determines whether or not the other cutting path L2 is within the operating range WS of the robot 40. The control unit 60 refers to the table data based on the information on the box size of the target box 12 at that time, and determines that the other cutting path L2 is not within the operation range WS, and thus proceeds to step S37.

  In step S37, the control unit 60 measures the distance to the other second tape 18 by the distance sensor 55 along the cutting path L2 with the transport operation of the box 12. First, the control unit 60 drives the conveyor 83 to move the box 12 in the transport direction X until the other second cutting path L2 enters the operation range WS of the robot 40. In this example, the box 12 is moved from the first transport position in the first direction X1. As a result, the box 12 is placed at the second transport position shown by the two-dot chain line in FIG. At the second transport position, the second tape 18 on the left side of the box 12 in FIG. Then, the control unit 60 drives the arm 43 of the robot 40 to bring the head 44 into the vertical position while keeping the distance sensor 55 at a height position (coordinate Z1) separated from the opening surface 13 by a predetermined distance. The distance sensor 55 is arranged in a direction in which the cutting path L2 on the opening surface 13 (see FIGS. 3 and 7) can be directed as a measurement target. The control unit 60 moves the head 44 in the upright posture along the second measurement path (XY coordinates) in the width direction Y different from the traveling direction in FIG.

  In this movement process, the distance sensor 55 measures the distance LZ in the vertical direction Z to the other second tape 18 at a plurality of points along the cutting path L2. The control unit 60 uses the information of the distance LZ in the vertical direction Z of the plurality of points, which is the measurement result of the distance sensor 55, as in the case of the above-described one second cutting path, to control the coordinate system of the second tape 18. A cutting path (XYZ coordinates) represented by The control system coordinates of the cutting path reflect changes in the position of the second tape 18 in the vertical direction Z.

  In the next step S39, the control section 60 cuts the other second tape 18 while controlling the height of the cutter 53 according to the detection distance of the distance sensor 55. That is, the control unit 60 controls the position of the cutter 53 along the cutting path (XYZ coordinates) of the other second tape 18 represented by the control system coordinates. At this time, the position of the cutter 53 is also controlled in the vertical direction Z during the cutting process of the second tape 18.

  The position of the head 44 indicated by a two-dot chain line in FIG. 19 is controlled along a cutting path L2 represented by control system coordinates in a posture obliquely inclined with respect to the other second tape 18. At this time, even if the second tape 18 is curved because the opening surface 13 of the box 12 is concave, since the position of the cutter 53 is controlled in the vertical direction Z, the cutter 53 is placed on the curved second tape 18. Along the cutting path L2. As a result, the cutting depth necessary for the cutter 53 is secured in the entire area in the longitudinal direction of the second tape 18, and the second tape 18 is reliably cut.

  In addition, when targeting the second cutting path L2, in step S37, the distance sensor 55 determines the distance in the transport direction X to the portion of the second tape 18 affixed to the side surface 12B of the box 12, and the distance in the vertical direction Z. Alternatively, the measurement may be performed, and the measurement result may be used to obtain the cutting path L2 represented by the control system coordinates reflecting the change in the position of the second tape 18 in the transport direction X. By controlling the position of the cutter 53 along the cutting path L2, even if the side surface 12B of the box 12 is concave or bulging, the cutter 53 is positioned in the transport direction X even if the second tape 18 is curved. Since the cutter 53 is controlled, the cutter 53 moves along the cutting path L2 on the curved second tape 18. As a result, even if the side surface 12B of the box 12 is curved, the cutting depth required for the cutter 53 is secured over the entire length of the second tape 18 in the longitudinal direction, and the second tape 18 is reliably cut.

  When the three tapes 17 and 18 are cut in this way, the large-sized box 12 is opened. Therefore, in step S40, the control unit 60 determines that the box 12 has been opened, and ends the tape cutting control.

<Cutting of tape in small size box>
Next, an example of the box 12 belonging to the small size will be described. As shown in FIG. 14, in the case of the small-sized box 12, the box 12 at the work position SP on the conveyor 83 at the work height position H2 is such that the entire opening surface 13 is within the operation range WS of the robot 40. I do. In step S35 in FIG. 20, the control unit 60 proceeds to step S36 to determine that the cutting path L1 is within the operating range WS of the robot 40.

  In step S36, the control unit 60 sequentially measures the distance to the first tape 17 using the distance sensor 55 along the cutting path L1. This measuring method is the same as that for the large-sized box 12. The control unit 60 drives the arm 43 of the robot 40, and in the case of the small-sized box 12, the distance sensor 55 is moved from the opening surface 13 to a predetermined position. The measurement target is moved along the first measurement path (XY coordinates) in a posture pointing downward, while maintaining the height position (coordinates Z1) separated by a distance. The control unit 60 stores information on the first measurement path (XY coordinates), the position coordinate Z1 in the vertical direction Z at the time of measurement by the distance sensor 55, and the distance LZ in the vertical direction Z of a plurality of points, which is the measurement result of the distance sensor 55. Then, a cutting path (XYZ coordinates) represented by the control system coordinates that reflects the change in the position of the cutting path of the first tape 17 in the vertical direction Z is determined.

  In the next step S38, the control unit 60 cuts the tape 17 while controlling the height of the cutter 53 according to the detection distance of the distance sensor 55. That is, the control unit 60 controls the position of the cutter 53 along the cutting path (XYZ coordinates) of the first tape 17 represented by the control system coordinates. At this time, the position of the cutter 53 is also controlled in the vertical direction Z during the cutting process of the first tape 17.

  As in the case of the large-sized box 12 shown in FIG. 18, even in the case of the small-sized box 12, even if the first tape 17 is curved because the opening surface 13 of the box 12 is concave, the cutter 53 Is controlled in the vertical direction Z, the cutter 53 moves along the cutting path on the curved first tape 17 along the path indicated by the dashed line arrow in FIG. As a result, the cutting depth required for the cutter 53 is secured over the entire area of the first tape 17 in the longitudinal direction, and the first tape 17 is reliably cut.

  Next, after switching the target to the second cutting path (step S41), in step S35, the control unit 60 determines that the second cutting path L2 is within the operation range WS of the robot 40. Therefore, in step S36, the control unit 60 measures the distance to the one second tape 18 by the distance sensor 55 along the cutting path L2. The control unit 60 drives the arm 43 of the robot 40 while the box 12 is at the working position SP on the conveyor 83, and keeps the distance sensor 55 at a height position (coordinate Z1) separated from the opening surface 13 by a predetermined distance. While the head 44 is in the upright posture, the distance sensor 55 is arranged in a direction capable of directing the measurement object below. The control unit 60 moves the head 44 in the vertical posture along the second measurement path (XY coordinates) in the width direction Y different from the traveling direction in FIG.

  In this movement process, the distance sensor 55 measures a plurality of points LZ in the vertical direction Z to one of the second tapes 18 along the cutting path L2. The control unit 60 controls the second tape 18 in which the change in the position of the second tape 18 in the vertical direction Z is reflected by using information on the distance LZ in the vertical direction Z of a plurality of points, which is the measurement result of the distance sensor 55. A cutting path (XYZ coordinates) represented by system coordinates is obtained.

  In the next step S38, the control unit 60 cuts one of the second tapes 18 while controlling the height of the cutter 53 according to the detection distance of the distance sensor 55. That is, the control unit 60 controls the position of the cutter 53 along the cutting path (XYZ coordinates) of the one second tape 18 represented by the control system coordinates. At this time, the position of the cutter 53 is also controlled in the vertical direction Z during the cutting process of the second tape 18.

  In the example of the large-sized box 12 shown in FIG. 19, the box 12 cuts the two second tapes 18 at two transport positions different in the transport direction X, but in the small-sized box 12, two second tapes 18 are cut. The tapes 18 are both located within the operating range WS of the robot 40. For this reason, while remaining at the work position SP on the conveyor 83, the head 44 is controlled in position along the cutting path L2 represented by the control system coordinates in a posture obliquely inclined with respect to the one second tape 18. Is done. At this time, even if the second tape 18 is curved because the opening surface 13 of the box 12 is concave, the position of the cutter 53 is controlled in the vertical direction Z, and the cutter 53 is moved along the cutting path L2 on the curved second tape 18. Move along. As a result, the cutting depth necessary for the cutter 53 is secured in the entire area in the longitudinal direction of the second tape 18, and the second tape 18 is reliably cut.

  Then, for the other second tape 18 as well, it is determined that the other second cutting path is within the operation range WS of the robot 40 (Yes in step S35). In step S36, the control unit 60 measures the distance to the second tape 18 with the distance sensor 55 along the cutting path L2. In the next step S38, the control unit 60 cuts the other second tape 18 while controlling the height of the cutter 53 according to the detection distance of the distance sensor 55.

  When all the tapes 17 and 18 of the box 12 are cut and the box 12 is opened, the control unit 60 drives the motor 92 of the elevating unit 87 to lower the conveyor 83 from the working height position to the standby position H0. . When the conveyors 81 to 83 are driven, the opened box 12 is unloaded from the conveyor 83 to the unloading conveyor 82, and the next box 12 to be unsealed is loaded onto the conveyor 83 from the carry-in conveyor 81. . Hereinafter, similarly, the boxes 12 carried on the conveyor 83 are opened one by one.

According to the third embodiment, the following effects can be obtained in addition to the corresponding effects in the first embodiment.
(8) The opening device 11 includes a camera 50 (an example of an imaging unit), an articulated robot 40 having an arm 43 to which a cutter 53 is attached at a distal end thereof and controlled by a control unit 60, and a box 12 And a raising / lowering mechanism 86 that raises the box 12 until the opening surface 13 reaches a height position where the camera 50 is focused. The camera 50 is fixed at a predetermined height position where the opening surface 13 of the box 12 can be imaged. Therefore, there is no need to move the camera 50 when imaging the opening surface 13. In addition, if the opening / closing surface 13 is located at a position where the movable area of the arm 43 to which the cutter 53 is attached at the distal end is wide is located, the elevation mechanism 86 is set so that the camera 50 is focused on the opening surface 13. The maximum size of the box 12 in which the cutter 53 can cut the tapes 17 and 18 can be increased.

  (9) The opening device 11 includes a conveyor 83 (an example of a transport mechanism) that horizontally transports the box 12 along the longitudinal direction of the tapes 17 and 18. If a part of the tapes 17 and 18 is in the movable area of the cutter 53 determined by the operation range WS of the robot 40 and the other part of the tapes 17 and 18 is not in the movable area, the control unit 60 performs the next cutting. Perform control. That is, the cutter 53 involves cutting the tapes 17 and 18 by a part and transporting the box 12 horizontally until the other part of the tapes 17 and 18 is within the operation range WS of the robot 40. The other parts of the tapes 17 and 18 are cut off by 53. For example, when a part of the first cutting path L1 is out of the operation range WS of the robot 40, the first tape 17 is transported in the transport direction X of the box 12 which is also the longitudinal direction of the first tape 17, and the first tape 17 is moved by the cutter 53. Cut 17 Further, for example, when a part of the second cutting path L2 is out of the operation range WS of the robot 40, the box 12 is transported by the conveyor 83, and the box 12 is moved to two different positions between the first transport position and the second transport position. Is cut, the two second tapes 18 are cut. Therefore, the tapes 17 and 18 can be cut by transporting the box 12 horizontally even to a large-sized box 12 in which a part of the tapes 17 and 18 is out of the movable area of the cutter 53. The maximum size of the box 12 from which the tapes 17 and 18 can be cut can be increased for the movable area of the arm 43 of the robot 40. In other words, the opening device 11 can be made compact for the maximum size of the box that can be opened.

  (10) In the case of a large-sized box 12 larger than the size threshold, when cutting the first tape 17, the control unit 60 conveys the box 12 by the conveyor 83 in the conveyance direction X which is the longitudinal direction of the first tape 17. . The maximum size of the box 12 that can be opened by cutting the tapes 17 and 18 can be increased for the movable area of the arm 43 of the robot 40.

  (11) One first tape 17 and two second tapes 18 are affixed to the opening surface 13 in a direction in which the directions intersecting each other are the longitudinal directions. In the case of a large-sized box 12 larger than the size threshold, the control unit 60 arranges the box 12 at two different transfer positions with the transfer by the conveyor 83, and at the two different transfer positions, the cutter 53 uses two second tapes. 18 are each cut. The maximum size of the box 12 that can be opened by cutting the tapes 17 and 18 can be increased for the movable area of the arm 43 of the robot 40.

The embodiment is not limited to the above, but may be modified as follows.
As shown in FIG. 22, in the configuration of the head 44 having no rollers, the control unit 60 controls the cutter 53 so that the axis of the cutter 53 forms an angle with the tape surface in the process of cutting the tapes 17 and 18. The inclination angle of 53 may be controlled. The inclination angle of the tape surface with respect to the horizontal plane is determined based on a change in the position of the tape surface in the vertical direction Z according to the distance to the tape surface measured by the distance sensor 55 moving along the cutting path of the tapes 17 and 18, and In accordance with the inclination angle of the tape surface, the inclination angle of the cutter 53 is controlled such that the inclination angle of the cutter 53 with respect to the tape surface falls within an appropriate allowable range. The control of the tilt angle of the cutter 53 is performed by the control unit 60 controlling the arm 43 of the robot 40 and controlling the tilt angle of the head 44. Further, an actuator for changing the tilt angle of the cutter 53 may be provided in the head 44, and the control unit 60 may control the actuator to control the tilt angle of the cutter 53. In addition, the inclination angle of the cutter 53 may be controlled so that the angle between the cutter 53 and the tape surface is always constant, or if the angle of the cutter 53 with the tape surface is out of the allowable range, the cutter 53 may be controlled within the allowable range. The inclination angle of the cutter 53 may be controlled so as to fall within the range.

  FIG. 21 is a comparative example in which the controller cuts the tapes 17 and 18 while keeping the inclination angle θh of the cutter 53 with respect to the horizontal plane constant. As shown in FIG. 21, when the inclination angle θh of the cutter 53 is constant, the tapes 17 and 18 are greatly inclined with respect to the horizontal plane due to the curvature of the opening surface 13 to which the tape 17 is attached as shown in FIG. In such a portion, the angle θt between the cutter 53 and the tape surface 17A becomes too smaller than an appropriate range, and there is a fear that a large load is applied to the cutter 53 when cutting the tape. In this case, the cutting performance of the tapes 17 and 18 by the cutter 53 is reduced, and the life of the cutter 53 due to the early wear and breakage is feared.

  On the other hand, in the embodiment shown in FIG. 22, the control unit 60 controls the tape surface in accordance with a change in the distance to the tapes 17 and 18 detected by the distance sensor 55 while the cutter 53 cuts the tapes 17 and 18. The inclination angle θc of the cutter 53 with respect to 17A and 18A is controlled to be within an allowable range. The control unit 60 changes the angle θh between the cutter 53 and the horizontal plane, so that the tapes 17 and 18 are large with respect to the horizontal plane due to the curvature of the opening surface 13 to which the tape 17 is attached as shown in FIG. Even at the inclined portion, the inclination angle θc between the cutter 53 and the tape surfaces 17A and 18A falls within an appropriate allowable range. Therefore, a large load is hardly applied to the cutter 53 when cutting the tape. For this reason, the cutting properties of the tapes 17 and 18 are improved, and at the same time, early wear and breakage of the cutter 53 are avoided, leading to a longer life of the cutter 53.

  The position detection unit is not limited to the elevation type height detection device 30 in which the sensor unit 32 moves in the height direction Z, but may be a mobile detection device in which the sensor unit 32 moves in the X direction or the Y direction. By arranging the boxes horizontally, the position of the tape in the cross direction intersecting with the opening surface 13 can be detected.

  In the first embodiment, both the height detection device 30 as an example of the position detection unit and the distance sensor 55 may be provided. The cutting paths L1 and L2 are obtained using the position in the cross direction of the opening surface 13 detected by the height detection device 30. The distance sensor 55 detects the distance to the tapes 17 and 18 and controls the position of the cutter 53 in the cross direction when cutting the tapes 17 and 18. As a result, the opening operation for opening the box 12 by cutting the tapes 17 and 18 can be performed at high speed, and the tapes 17 and 18 that are curved due to the opening surface 13 being dented can be reliably cut.

  The present invention is not limited to the configuration in which the box 12 is opened with the opening surface 13 of the box 12 facing upward. The box 12 may be opened with the opening surface 13 facing sideways, or the box 12 may be opened with the opening surface 13 facing down. Even in such a posture of the box 12, the position of the tapes 17, 18 in the cross direction intersecting (for example, orthogonally) with the unsealing surface 13 on which the tapes 17, 18 of the box 12 are stuck is detected by the position detection unit, and A cutting path on the opening surface 13 is obtained from an image of the opening surface 13g in the image from an image of the opening surface 13 to which the tapes 17 and 18 are attached by the camera 50. Thereby, the position of the tapes 17 and 18 in the cross direction (for example, the X direction or the Y direction) and the cutting path on the unsealing surface 13 can appropriately control the position of the cutter 53 to cut the tapes 17 and 18 appropriately. .

  For example, the robot 40 grips the box 12 with the arm 43, controls the direction of the box 12 with the arm 43, directs the opening surface 13 to the fixed camera 50, and causes the camera 50 to image the opening surface. Further, the direction of the box is controlled by the robot 40, the box is turned in a direction in which the position in the cross direction of the tape can be detected with respect to the detection light from the position detection unit, and the position detection unit faces the opening surface 13 of the box 12. The position in the cross direction of the tapes 17 and 18 stuck may be detected. Furthermore, the robot 40 may hold the box 12 and move the box 12 relative to the fixed cutter 53 so that the cutter 53 cuts the tapes 17 and 18 attached to the opening surface 13.

  The height position of the camera 50, that is, the distance from the camera 50 to the opening surface 13 is obtained from the size of the opening surface 13g when the image is taken from the height of the predetermined imaging position based on the box identification information such as the box number. You may. In this case, the height detection device 30 or the distance sensor 55 can be made unnecessary. In this configuration, the camera 50 and the calculation unit 62 that calculates the distance from the camera 50 to the opening surface 13 using the captured image of the camera 50 and the box identification information that defines the size of the opening surface 13 of the box 12. An example of the position detection unit is configured.

  In the second embodiment, in the cutting process in which the cutter 53 cuts the second tape 18, the distance sensor 55 detects the distance to the second tape 18 on the side surface 12B of the box 12 or the side surface 12B instead of the opening surface 13. May be. According to this configuration, the position of the cutter 53 can be controlled by following the curvature of the side surface 12B, and the second tape 18 can be appropriately cut even if the side surface 12B is curved. In addition, a plurality of distance sensors are provided, and in the cutting process of cutting the second tape 18, the distance to the unsealing surface 13 and the distance to the side surface 12B are measured by the two distance sensors 55, and the cutter 53 is moved in the height direction. The second tape 18 may be cut by moving in the width direction Y while controlling the position in the Z and X directions. According to this configuration, the second tape 18 can be more appropriately cut by following the curve such as the dent of the opening surface 13 and the curve of the dent of the side surface 12B.

  In the second embodiment, before cutting the tape, the distance sensor 55 is first moved along the cutting path L1 while the cutter 53 is separated from the tape, and the distance between the position in the X direction and the distance LZ to the tape 17 is determined. Get the information of correspondence. Then, the tape 17 may be cut by moving the cutter 53 along the cutting path L1 while controlling the position of the cutter 53 in the cross direction (the height direction Z) based on the acquired information.

  In each of the above embodiments, the cutter unit 51 is supported by an air cylinder, and a roller as an example of a rolling element is pressed against the opening surface 13 or the side surface 12B while being urged by a small air pressure applied to the air cylinder. The tapes 17 and 18 may be cut by controlling the position of the tape 53 while following the surface shape of the opening surface 13 or the side surface 12B. According to this configuration, even if there is a dent in the opening surface 13 or the side surface 12B of the box 12, the tapes 17, 18 can be cut while the cutter 53 follows the dent in the opening surface 13 or the side surface 12B. As an example of the rolling element, a ball or a roller may be used instead of the roller.

  In the second and third embodiments, the distance in the vertical direction Z is measured by the distance sensor 55 along the longitudinal direction of the first tape 17, but the first tape 17 is also measured in the vertical direction Z in the width direction. May be measured. For example, when the tape 17 is stuck in a state where the pair of flaps 16 overlap, a step may be formed in the width direction of the tape 17. By measuring the distance in the vertical direction Z along the width direction of the tape, the step between the overlapping flaps 16 is detected. Since the tape 17 is raised from the lower flap 16 at the step, the tape 17 is cut at the raised portion. In this case, since the cutter 53 cuts the tape 17 and does not cut the flap 16 very much, a cutting load is hardly applied to the cutter 53, which can contribute to a longer life of the cutter 53.

  According to the method of determining the four corners of the outer shape from the outer shape of the opening surface 13 as four vertices, if the ends of the tapes 17 and 18 extend out of the box 12, the ends of the tapes 17 and 18 will be processed by image processing. May be erroneously detected as the vertex at the tip of In this case, if the cutting path is determined from the erroneously detected vertex, it may cause a measurement error of the distance by the distance sensor 55 or a cutting error of the tapes 17 and 18. In particular, the cutting error of the second tape 18 is more likely to occur than the first tape 17. Further, the first tape 17 can be opened even when cut using a straight line connecting the midpoints as a cutting path, but the second tape may not be cut due to deformation of the box. In other words, since the I-paste is only the first tape, it can be cut even with a straight cutting path, but the H-paste can be cut into a square when the box 12 is deformed and the side of the opening surface 13 is curved. If the straight line connecting the vertices is used as the cutting path, the second tape 18 may not be cut in some cases. Therefore, a straight line connecting two midpoints of each of the four vertices is used as a cutting path, and in the case of H-pasting, an extension of an extension of a part of a straight part such as the center of four sides forming the outer shape of the unsealing surface. Find the intersection as the vertex.

  In this case, the method of obtaining the outer shape of the unsealing surface 13 may be switched between H sticking including the second tape 18 and I sticking not including the second tape 18. For this reason, in the I-pasting, the four corners of the outer shape of the opening surface 13 are defined as four vertices, and the respective midpoints of two vertices of the four vertices facing in the direction intersecting with the first tape 17 are connected. The straight line is used as a cutting path, and the point of intersection of an extension line extending a part of a straight line portion such as the center of four sides forming the outer shape of the opening surface 13 is determined as a vertex in the H bonding.

  In the third embodiment, an example of the transport mechanism may be a conveyor 83 having no elevating function instead of the elevating conveyor 83. For example, the conveyor 83 is located at a height position where the opening surface 13 of the largest box 12 is located near the height position where the operation range WS of the robot 40 is sufficiently large compared to the box size, or near the maximum position of the operation range WS of the robot 40. Or the like, the tapes 17 and 18 of the box 12 can be cut without having the elevating function.

  In the third embodiment, the opening surface 13 of the box 12 is arranged at the focal position of the camera 50 by raising the conveyor 83 from the standby position H0 by the elevating mechanism 86. However, the conveyor 83 is moved by the elevating mechanism 86 to the standby position H0. The opening surface 13 of the box 12 may be arranged at the focal position of the camera 50 by lowering the box. In this case, if the unsealing surface 13 can be arranged at a height position where the operation range WS of the robot 40 is wider than when the robot is at the standby position H0, the movement from the standby position to the work height position will be ascending and descending. Either may be used.

  -A dynamic sensor may be provided. A load cell or the like can be given as a dynamic sensor. A roller for measurement is provided in the cutter unit at a location different from the pair of rollers for limiting the amount of insertion of the cutter. Rolling the opening on the opening surface while pressing the roller against the opening surface and moving the roller while adjusting the height of the roller with the arm while keeping the pressure or distortion received by the roller arm constant, in the longitudinal direction of the tape on the opening surface Measure the shape along. The tape shape may be measured by such a contact-type sensor.

  In the third embodiment, the operation range WS, which is the P-point operation range of the robot 40, is regarded as the movable area of the cutter 53 when the head 44 is mounted on the arm. The actual movable range of the cutter 53 derived from the posture of the robot 40 at the time of cutting may be used as the movable area of the cutter 53. In this case, since the movable area of the cutter 53 is wider than the operation range WS, the box size in which the tape cutting operation is performed without accompanying the transport of the box 12 can be increased.

  In the third embodiment, as in the second embodiment, in the process of cutting the tapes 17 and 18, the distance sensor 55 measures a distance to a position in front of the cutter 53 in the traveling direction and uses the measured distance as a basis. The position of the cutter 53 may be controlled in the vertical direction Z along the cutting path.

In the first and second embodiments, the camera 50 as an example of the imaging unit may be fixed at a predetermined height above the working position higher than the opening surface 13.
The second tape 18 may be cut before the first tape 17.

・ The box is not limited to a rectangular prism such as a rectangular parallelepiped, but may be another polygonal prism such as a triangular prism.
The height detecting unit is not limited to the height detecting device separate from the robot, and may be attached to the arm 43 or the head 44 of the robot 40. In this case, a detection light or a sound wave is irradiated onto the opening surface 13 from above the opening surface 13, the reflected light or sound wave is detected, the distance to the opening surface 13 is detected, and the height position of the opening surface 13 is detected. May be used as a non-contact type detection unit for detecting the detection.

  The robot 40 is not limited to an articulated robot such as a vertical articulated type or a horizontal articulated type, and is an industrial robot using other mechanisms such as a rectangular coordinate type, a cylindrical coordinate type, a polar coordinate type, and a parallel link type. May be.

  The opening device of each of the above embodiments may be configured without the robot 40. For example, a position detecting unit that detects the positions of the tapes 17 and 18 in an intersecting direction (for example, orthogonally) intersecting (for example, orthogonally) to the opening surface 13 of the box 12, an imaging unit that images the opening surface of the box, and an actuator that moves the cutter 53 are provided. The opening device 11 may be provided with a cutting mechanism having the control unit 60. Further, for example, the opening device 11 may be configured to cut the tapes 17 and 18 attached to the opening surface 13 of the box 12 by moving the fixed cutter 53 and the box 12 with respect to the cutter 53.

-The cutter is not limited to the ultrasonic vibration type cutter, but may be a cutter that is physically cut with a blade.
The box 12 may be closed by a so-called “vertical application” by the first tape 17 attached along the center line of the opening surface 13. In addition, the box 12 has a first tape attached along a first central line extending vertically on the opening surface 13 and a second central line extending laterally on the opening surface 13 in a state of intersecting with the first tape. The second tape may be closed with a so-called “cross paste”.

The tapes 17 and 18 are not limited to the adhesive tapes, but may be tapes attached to the box 12 with glue or an adhesive. Further, the tapes 17 and 18 may be welded to the box 12.
An inspection unit that images the cutter 53 with the camera 50 or another camera and inspects the cutter for damage based on the captured image may be provided. For example, the camera 50 is attached to the head 44 via a tilting mechanism so that the imaging direction can be changed, and the camera 50 images the cutter 53 regularly or irregularly. The inspection unit inspects the cutter 53 for damage and wear based on the image of the cutter 53. According to this configuration, breakage and wear of the cutter 53 can be found at an early stage.

  -The box is not limited to the cardboard box made of paper, but may be a cardboard box made of plastic.

  10: Box opening system, 11: Box opening device, 12: Box, 12B: Side surface as an example of an adjacent surface, 12K: Opening, 12g: Box in image, 13: Opening surface, 13g: Image Opening surface, 16 flap, 17 first tape as an example of tape, 18 second tape as an example of tape, 20 transport device, 21 conveyor, 22 positioning device, 23 stopper device, 24 Guide device, 26 stopper, 28 guide member, 29 sensor, 30 height detecting device as an example of a position detecting unit, 31 lifting mechanism as an example of a first moving mechanism, 32 sensor unit, 40 ... Robot as an example of a second elevating mechanism, 43... Arm, 44... Head, 50... Camera as an example of an imaging unit, 51... Cutter unit, 53. ... Image processing unit, 62 ... Calculation unit, 63 ... Memory, 70 ... Operation panel, 71 ... Display unit, 83 ... Conveyor as an example of a transport mechanism, 83M ... Motor, 85 ... Transport belt, 86 ... Elevating mechanism, 87 ... Elevating unit, 88 guide rod, 89 slider, 90 support table, 92 motor, 93 power transmission mechanism, 97 drive belt, 100 timing belt, HL detection light, CI image (captured image), A, B, C, D: vertex, E, F: midpoint, L1: first cutting path as an example of a cutting path, L2: second cutting path as an example of a cutting path, EL: edge line, LZ ... Distance, H0: Standby position, H1: Working height position, WS: Operating range, X: Transport direction, X1: Transport direction, Y: Y direction (width direction), Z: Z direction (an example of cross direction) Direction).

Claims (10)

A box opening device for cutting the tape attached along the periphery of the flap closing the opening of the box and opening the box,
A position detection unit that detects the position of the tape in an intersecting direction that intersects the unsealing surface on which the tape is pasted in the box,
An imaging unit that captures the opening surface from an imaging position separated in the cross direction to obtain a captured image including the opening surface,
A cutter that moves relative to the box and cuts the tape;
The position of the tape in the cross direction detected by the position detection unit, and the tape of the control coordinate system determined based on the cutting path of the tape in the image coordinate system determined from the position of the outer shape of the unsealing surface in the captured image A control unit for controlling the position of the cutter along the cutting path to cut the tape,
A box opening device comprising: The position detection unit is a sensor unit that can move in the cross direction while emitting detection light to the box in a direction parallel to the opening surface, and a first movement mechanism that moves the sensor unit in the cross direction. Having a position in the cross direction of the tape by moving the sensor unit in the cross direction,
The box opening device according to claim 1, further comprising a second moving mechanism that moves the imaging unit to the imaging position. A distance sensor that measures a distance to the tape in the cross direction,
The control unit causes the distance sensor to detect a plurality of distances to the tape along the cutting path of the tape, and controls the position of the cutter along the cutting path to cut the tape. 3. The box opening device according to claim 2, wherein the position of the cutter is controlled in the cross direction according to a change in the distance to the box. The second moving mechanism is an articulated robot that has an arm to which the imaging unit and the cutter are attached to a distal end and is controlled by the control unit,
The box opening device according to claim 3, wherein the distance sensor is attached to a tip portion of the arm. The position detection unit is a distance sensor that measures the distance to the tape in the cross direction to detect the position of the tape in the cross direction,
The control unit causes the distance sensor to detect a plurality of distances to the tape along the cutting path of the tape, and controls the position of the cutter along the cutting path to cut the tape. The box opening device according to claim 1, wherein the position of the cutter is controlled in the cross direction in accordance with a change in the distance to the box. The imaging unit is fixed at a predetermined height position capable of imaging the opening surface of the box,
An articulated robot controlled by the control unit and having an arm to which the cutter is attached at a tip end,
An elevating mechanism that raises or lowers the box until the opening surface of the box reaches a height position that is the focus of the imaging unit,
The box opening device according to claim 5, further comprising: Further comprising a transport mechanism for transporting the box horizontally along the longitudinal direction of the tape,
The control unit, when a part of the tape is in the movable area of the cutter and another part of the tape is not in the movable area, cutting the part of the tape by the cutter, Cutting the other part of the tape by the cutter with a transport operation of horizontally transporting the box until the other part of the tape is located at the cut position in the movable area, The box opening device according to claim 4 or 6, wherein   The controller, in the process of cutting the tape by the cutter, controls the inclination angle of the cutter with respect to the surface of the tape to be within an allowable range according to a change in the distance to the tape. The box opening device according to any one of claims 3 to 7. A first tape affixed to the boundary between the two flaps on the opening surface of the box, and a second tape affixed along the boundary between the two flaps and the side surface of the box, to be cut,
The control unit calculates the cutting path of the first tape from the position in the cross direction and the position coordinates of a plurality of image coordinate systems including two or more vertices in the outline of the opening surface in the captured image. Cutting the first tape by controlling the position of the cutter along the determined cutting path;
An edge line is determined from the position in the cross direction and an image coordinate system edge line at which the unsealing surface and the adjacent surface in the captured image intersect, and the cutter is cut along the determined cutting path along the edge line. The box opening device according to any one of claims 1 to 8, wherein the second tape is cut by controlling the position of the box. A box opening method for cutting a tape stuck along a peripheral edge of a flap closing an opening of a box and opening the box,
A position detection step of detecting a position of the tape in an intersecting direction intersecting an opening surface of the box on which the tape is stuck;
An imaging step of imaging the opening surface of the box to obtain a captured image,
The position determined in the cross direction of the tape detected in the position detecting step and the cutting path determined in the image coordinate system of the tape determined from the outer shape position of the unsealing surface in the captured image acquired in the imaging step. Controlling the position of the cutter along the cutting path of the tape to cut the tape,
A method for opening a box, comprising: