Unpacking device, cutter hand, unpacking method

Abstract

To provide a technology that can reduce the time required to unpack packaging and also reduce the amount of swarf produced when cutting packaging.SOLUTION: The unpacking device is configure to unpack a packing body and is equipped with: a robot; and a cutter hand attached to a tip of the robot. The cutter hand has: a blade section including a blade for cutting the packing body; and a blade holding section that holds the blade section. The blade holding section moves through a space around a first surface of the packing body while bringing the blade section into contact with the packing body, wherein the first surface extends in both: a second direction non-parallel to a first direction being an axial direction of a first shaft of the blade holding section; and a third direction orthogonal to the second direction. A distance, of when the blade holding portion moves around a corner of the first surface, between a cutting edge of blade portion and a position where the cutting edge is inserted into the packing body, is longer than a distance, of when the blade holding portion moves along a side of the first surface, between the cutting edge of the blade portion and the position where the cutting edge is inserted into the packing body.SELECTED DRAWING: Figure 8

Description

Technical Field

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[0001] The present invention relates to an apparatus and a method for unpacking a package.

Background Art

[0002] In today's production sites, articles such as products, semi-finished products, and parts are transported to their destinations in a state of being packed with packing materials such as cardboard boxes and various cushioning materials in order to prevent accidents during transportation and transport them safely. At that time, a substantially box-shaped object in which an article, which is an object to be transported, is stored inside the packing material is referred to as a package. When the package arrives at the destination, it is unpacked to take out the article inside.

[0003] As a means for unpacking this package, for example, the technique of Patent Document 1 is known. Patent Document 1 discloses a cutting cutter that cuts the package while moving on the corners of the package.

Prior Art Documents

Patent Documents

[0004] <​​​​​​​​​​​​​​​​ In view of the above problems, the present invention aims to provide a technology that can shorten the time required to unpack a package and reduce the amount of chips generated when cutting a package. [Means for solving the problem]

[0007] The unpacking device according to the present invention unpacks a package and comprises a robot and a cutter hand attached to the tip of the robot. The cutter hand has a blade portion including a blade for cutting the package and a blade holder portion for holding the blade portion. The blade holder portion moves in the space around the first surface of the package, extending in both a second direction non-parallel to the first direction which is the axial direction of the first shaft portion of the blade holder portion, and a third direction perpendicular to the second direction, while keeping the blade portion in contact with the package. When the blade holder moves around the corner where one side of the packaging body meets another side, the distance between the blade tip and the insertion point of the blade tip into the packaging body is longer than the distance between the blade tip and the insertion point of the blade tip into the packaging body when moving along one side or the other side. The blade tip rotates as it is inserted from one side to the other side.

[0008] Furthermore, the unpacking method according to the present invention is a method of unpacking a package using the unpacking device described above. [Effects of the Invention]

[0009] According to the present invention, the time required to unpack the packaging can be reduced, and the amount of chips generated when cutting the packaging can be reduced. [Brief explanation of the drawing]

[0010] [Figure 1] A schematic diagram of an unpacking device according to one embodiment of the present invention. [Figure 2] A rear view showing an example of the structure of the cutter hand of an unpacking device according to one embodiment of the present invention. [Figure 3] A front view showing an example of the structure of the cutter hand of an unpacking device according to one embodiment of the present invention. [Figure 4] A top view showing an example of the structure of the cutter hand of an unpacking device according to one embodiment of the present invention. [Figure 5] A right-side view showing an example of the structure of the cutter hand of an unpacking device according to one embodiment of the present invention. [Figure 6] A right-side view showing an example of the structure of the blade portion of a cutter hand. [Figure 7] A schematic diagram illustrating the direction of the blade tip when cutting packaging materials. [Figure 8] A schematic diagram illustrating the trajectory of the blade tip when cutting packaging material. [Modes for carrying out the invention]

[0011] The following describes this embodiment in detail. In each figure used to illustrate the embodiment, the same components will be given the same names and reference numerals as much as possible, and repeated explanations will be omitted. The following explanation assumes that the three coordinate axis directions in the three-dimensional Cartesian coordinate system are the first direction, the second direction, and the third direction, respectively. In the following explanation, the first direction is assumed to be the vertical direction, and unless otherwise noted, the vertical direction is assumed to be the direction of the vertical line (hereinafter referred to as the "vertical direction"). That is, in the following explanation, the first direction is assumed to be perpendicular to both the second and third directions, and the first and second directions are assumed to be non-parallel. Furthermore, in the following explanation, both the second and third directions are assumed to be horizontal directions, and the second and third directions are assumed to be perpendicular. In the following explanation of this embodiment, the second direction is the longitudinal direction of the packaging body, which will be described later. The third direction is the width direction of the packaging body. The longitudinal direction of the packaging body is the direction of the longer side of the top surface of the rectangular parallelepiped packaging body, and the width direction is the direction of the shorter side of the top surface. Of course, the second and third directions are interchangeable, and the second direction may be the width direction of the packaging, or the third direction may be the longitudinal direction of the packaging. Thus, in the following description of this embodiment, the second and third directions represent the directions of two types of edges on the top surface (first surface) of the packaging, respectively.

[0012] Figure 1 is a schematic diagram of an unpacking device 1 according to one embodiment of the present invention. The unpacking device 1 shown in Figure 1 is a device that is installed, for example, on a production line in a factory and unpacks packages 80 that are sequentially transported at predetermined intervals. As shown in Figure 1, the unpacking device 1 generally comprises a robot 10 and a cutter hand 20 attached to the tip of the robot 10.

[0013] The robot 10 in this embodiment is a six-degree-of-freedom vertical articulated robot, with six rotary joints (hereinafter sometimes referred to as "links") on its manipulator. A cutter hand 20 for unpacking the package 80 is attached to the tip of the robot 10. This cutter hand 20 is a type of tool called an end effector, and mainly consists of a blade 60 and a blade holder 40 that holds the blade 60 (details will be described later).

[0014] The operation of the unpacking device 1 is controlled by the position control of the robot 10, which uses an arbitrary point on the tip of the blade attached to the blade portion 60 of the cutter hand 20 (hereinafter referred to as the "blade tip") as a reference point and specifies the position in a three-dimensional Cartesian coordinate system where this reference point will move. When the motion control unit (not shown) of the robot 10 receives an input operation specifying the position in a three-dimensional Cartesian coordinate system as the destination of the blade tip, it determines the amount of rotation of each of the six rotary joints according to the input and transmits a control signal to each rotary joint that conveys the amount of rotation. Each rotary joint is equipped with an actuator, which is controlled by the received control signal by the rotation angle, amount of rotation, rotation speed, rotation acceleration, rotation angular velocity, etc. Then, when each rotary joint rotates according to the received control signal, the robot 10 changes its posture. The robot 10 performs the necessary actions based on this change in posture and moves the blade holding portion 40 of the cutter hand 20 in a substantially horizontal direction, thereby moving the blade tip of the blade portion 60 connected to the blade holding portion 40 to the specified position. In other words, the blade holder 40 is connected to the robot 10 and moves according to the movements of the robot 10 performed in accordance with the control signals of the motion control unit. The operator who sets the operation of the unpacking device 1 can specify the path the blade will take (hereinafter also referred to as the "trajectory") by specifying multiple positions in a three-dimensional Cartesian coordinate system, along with the order in which they will pass, when specifying the destination position of the blade. The trajectory is not limited to the blade, but can also be set as the position where the guide 65 and the packaged body 80 come into contact. In this case, the trajectory can be set based on the shape of the packaged body 80, making it easy to create the trajectory. As long as the positional relationship between the trajectory and the blade 62 can be determined, other positions can be used as the trajectory, and are not limited to these. The robot 10 of this embodiment can cut from any side of the packaged body 80 shown in Figure 1, but the side that is cut first is the side that is not visible in the Y-axis direction as shown in Figure 1, which is referred to as the first side 80a, and the side that is cut after the first side 80a is cut is referred to as the second side 80b that is visible in the X-axis direction.As will be explained in more detail later, when transitioning from the cutting process of the first side surface 80a to the cutting process of the second side surface 80b, the cutter hand 20 rotates around the edge where the first side surface 80a and the first side surface 80b are connected, and continues cutting in accordance with the second side surface 80b.

[0015] The upper surface (hereinafter also referred to as the "placement surface") 90 of the conveyor belt of the belt conveyor device that transports the packaged bodies 80 is made of a material with a high coefficient of friction and has an anti-slip effect. In addition, two fixed stoppers (hereinafter referred to as "fixed stoppers") 91 and one movable stopper (hereinafter referred to as "movable stopper") 92 are provided on this placement surface 90. Furthermore, the fixed stoppers 91 and the movable stopper 92 that face the sides of the packaged bodies 80 are each provided with a sheet-like anti-slip material made of a material such as rubber with a high coefficient of friction. Each packaged body 80 is, for example, in the shape of a rectangular parallelepiped and is fixed on the placement surface 90 with its lower sides clamped by the fixed stoppers 91 and the movable stopper 92. Of each packaged body 80, the surface that contacts the placement surface 90 is called the bottom surface, and the surface that faces the bottom surface is called the top surface or upper surface. The top surface is the surface that can be seen when looking from a high position to a low position in the first direction described above. The surface visible in the top view is the top surface. The top surface of the packaging body 80 and the four surfaces connected to the top surface are called the sides. In this state, taking into account the dimensions and position of the packaging body 80, multiple destinations for the cutting edge in a three-dimensional Cartesian coordinate system are set along with the order in which they move. Then, the motion control unit of the robot 10 operates the robot 10 according to the settings. As a result of this operation of the robot 10, the cutter hand 20 moves approximately horizontally in the second or third direction along the side surface where the cutting edge 63 is inserted, with the cutting edge inserted into the side surface of the packaging body 80, and the side surface of the packaging body 80 is cut approximately horizontally. When the cutter hand 20 completes one full rotation around the packaging body 80, all sides of the packaging body 80 are cut approximately horizontally, the top surface of the packaging body 80 becomes removable, and the packaging body 80 is opened (details will be described later in relation to Figure 8). The top surface of the packaging body 80 may also be removed by attaching a suction member to the robot 10 and using suction. In this case, one robot 10 can perform both the cutting and removal of the top surface, and if the robot 10 removes the cut top surface and transports it to another area before the next package 80 to be cut is transported, the overall production efficiency of the production line will be improved. Alternatively, the removal may be performed by a separate robot or by human hands.

[0016] In the present embodiment, the robot 10 has been described as an articulated vertical robot having six links. However, the number and arrangement of the robot's links can be appropriately changed. Also, the robot may be of a serial link type, and may be another type of robot such as a scalar robot, but is preferably an articulated vertical robot.

[0017] Next, an overview of the cutter hand 20 will be described with reference to FIGS. 2 to 5. FIGS. 2 to 5 are diagrams showing an example of the structure of the cutter hand 20. Among these, FIG. 2 is a front view, FIG. 3 is a rear view, FIG. 4 is a top view, and FIG. 5 is a right side view. As described above, the cutter hand 20 mainly includes a blade portion 60 and a blade holding portion 40 that holds the blade portion 60. That is, the cutter hand 20 has a blade portion 60 and a blade holding portion 40.

[0018] The blade holding portion 40 is a member for fixing and holding the blade portion 60 of the cutter hand 20 to the tip of the robot 10. This blade holding portion 40 is generally composed of a structure (hereinafter referred to as a "laminated structure") 44 formed by laminating two metal plate-like members arranged substantially horizontally in the vertical Z-axis direction, and a substantially cylindrical first shaft portion 42 provided vertically at one end side in the longitudinal direction of the laminated structure 44. A substantially rectangular opening 45 that connects the upper and lower surfaces is provided in one of the two plate-like members constituting the laminated structure 44, and inside the opening 45, a first elastic body 41 that expands and contracts in the width direction of this plate-like member and compresses and tries to expand in the Y-axis direction is arranged. The other end side in the longitudinal direction of the laminated structure 44 is connected to the blade portion 60 disposed below it, that is, at a lower position in the Z-axis direction.

[0019] The first elastic body 41 is a substantially cylindrical metal coil spring with the horizontal direction as the axial direction. One end side of the first elastic body 41 is fixed to the laminated structure 44 of the blade holding portion 40 by being locked to a fixing portion provided at one end side in the longitudinal direction, which is the Y-axis direction, of the substantially rectangular opening 45. On the other hand, the other end side of the first elastic body 41 is fixed to the blade portion 60. That is, the blade holding portion 40 is connected by the blade portion 60 and the first elastic body 41.

[0020] The first shaft portion 42 has a rotation axis substantially parallel to the vertical line, penetrates through two plate-like members constituting the laminated structure 44 in the vertical direction, and is installed so as to extend upward from the upper surface side of the upper plate-like member. The upper end of the first shaft portion 42 is connected to the tip of the robot 10. The first shaft portion 42 is rotatable in the horizontal direction within the range illustrated by the white arc-shaped arrow in FIG. 4, and as a link provided in the blade holding portion 40 of the cutter hand 20 separately from the six links of the robot 10, it provides an additional degree of freedom to the operation of the unpacking device 1. Thereby, the blade portion 60 can rotate around the rotation axis of the first shaft portion 42 of the blade holding portion 40 provided in the vertical direction. That is, when the side surface portion 65b of the guide 65 contacts the side surface of the package 80, the blade 62 can be brought into contact so as to rotate toward the side surface of the package 80. Thus, when the cutter hand 20 is operated along a locus assuming that the side surface of the package 80 is flat, even if there is a distortion such as a convex portion protruding outward from the plane of the side surface or a concave portion facing the inside of the package 80 on the side surface of the package 80, the force with which the extended first elastic body 41 tries to return is applied, so that the side surface portion 65b is pressed against the side surface of the package 80. Thereby, since the blade 62 is pressed without leaving the side surface portion of the package 80, the blade 62 can cut the side surface portion of the package 80. That is, even when the locus is set with the X-axis or Y-axis fixed, the first elastic body 41 can cut the side surface of the package 80 by pressing the blade tip 63 against the inside of the package 80. Thereby, since the side surface can be cut without strictly setting the locus to the shape of the side surface of the package 80, the work of the operator setting the locus becomes easy.

[0021] Furthermore, a second elastic body 43, whose direction of expansion and contraction is vertical, is attached coaxially to the first shaft portion 42, on the outer side of its side surface. In other words, the second elastic body 43, compressed in the first direction which is the Z-axis direction, is wound around the first shaft portion 42. This second elastic body 43 is a roughly cylindrical metal coil spring with its axial direction being vertical. That is, the elastic body 43 is attached to the blade holding portion 40 in the vertical direction. This allows the cutting of the packaging 80 to be stabilized by appropriately following the vertical distortion of the shape of the packaging 80 when cutting it. In other words, the upper surface portion 65a of the guide 65 is pressed against the top surface of the packaging 80 by the second elastic body 43. When the cutter hand 20 is operated along a trajectory that assumes the top surface of the packaging body 80 is flat, even if the top surface of the packaging body 80 is not flat and has distortion, the compressed second elastic body 43 exerts a force that tries to expand, so that even if the top surface of the packaging body 80 has distortion including a recessed part that is concave towards the bottom surface and a convex part in the height direction, the top surface portion 65a is pressed towards the top surface. As a result, when the cutter hand 20 scans the sides and top surface of the packaging body 80, the blade 62 scans in accordance with the distortion of the top surface, making it possible to cut the sides of the packaging body 80 while maintaining a constant distance from the top surface. Therefore, it is possible to cut the sides of the packaging body 80 at a constant distance from the top surface without creating a trajectory that precisely sets the state of the top surface.

[0022] Thus, the blade holder 40 is connected to the robot 10 at the upper end of the first shaft portion 42. In addition, the other end of the blade holder 40 in the longitudinal direction of the laminated structure 44 is connected to the blade portion 60.

[0023] The blade section 60 is a component that includes a blade 62 for unpacking the package 80. The outline of this blade section 60 will be described with reference to Figures 2-5, and further to Figure 6. Figure 6 is a right-side view showing an example of the structure of the blade section 60 of the cutter hand 20. As shown in Figures 2-6, the blade section 60 is composed of a second shaft section 61, a blade 62, a cutter holder 64, and a guide 65.

[0024] The second shaft portion 61 is a substantially cylindrical member having a rotation axis substantially parallel to the vertical line, and its upper end is connected to the laminated structure 44 of the blade holding portion 40. In this description of the embodiment, for the sake of explanation, the second shaft portion 61 is organized as a component of the blade portion 60, but naturally, the second shaft portion 61 may also be described as being included in other components, such as the blade holding portion 40. The same applies to the other components.

[0025] The second shaft portion 61 is rotatable in the horizontal direction, i.e., in the XY plane, and, separate from the six links of the robot 10, is a link provided on the blade portion 60 of the cutter hand 20, providing further freedom of movement to the unpacking device 1.

[0026] In other words, the unpacking device 1 of this embodiment is configured as an eight-degree-of-freedom device by including, in addition to the six links provided on the robot 10, a first shaft portion 42 provided on the blade holding portion 40 of the cutter hand 20 and a second shaft portion 61 provided on the blade portion 60 of the cutter hand 20. Of these, the six links provided on the manipulator of the robot 10 can each have their rotation amount controlled according to the control signal of the robot 10. On the other hand, the first shaft portion 42 and the second shaft portion 61 rotate mainly in response to the reaction force received from the contact point between the blade portion 60 of the cutter hand 20 and the packaged body 80 when cutting the side of the packaged body 80. However, the first shaft portion 42 and the second shaft portion 61 may be configured to have their rotation amount controlled according to the control signal of the robot 10, similar to the six links of the robot 10, by incorporating motors that control the amount of rotation according to the control signal of the robot 10.

[0027] The blade 62 is for cutting the side of the packaging 80. In the unpacking device 1 of this embodiment, the blade 62 is an ultrasonic cutter. When cutting the packaging 80, the blade 62 is inserted into the side of the packaging 80, and the blade tip 63 penetrates the side of the packaging 80. In this state, the blade tip 63 moves substantially horizontally along the side of the packaging 80, thereby cutting the side of the packaging 80. On the other hand, the base end of the blade 62 is protected by a substantially cylindrical cutter holder 64 that is arranged coaxially with the blade 62.

[0028] When the robot 10 starts moving with the blade tip 63 penetrating the side of the packaging 80, the blade holder 40 fixed to the tip of the robot 10 moves approximately horizontally along the side of the packaging 80. At this time, the blade 60 moves in accordance with the blade holder 40. As a result, the blade tip 63 moves approximately horizontally while penetrating the side of the packaging 80, cutting the side of the packaging 80 in an approximately horizontal direction. The positional relationship will be explained below, but since the robot 10 moves in accordance with the side of the packaging 80, the positional relationship of the XY axes will change. For this reason, the explanation will use the state in which the cutting of the first side 80a, which is the first side of the packaging 80 to be cut, begins.

[0029] Furthermore, the blade portion 60 is equipped with a guide 65 positioned around the cutting edge 63. This guide 65 moves along the side surface of the packaging 80 together with the blade 62 when cutting the packaging 80, stabilizing the cutting of the packaging 80. In other words, the unpacking device 1 includes a guide 65 that is movable along the surface of the packaging 80. This guide 65 has a roughly L-shaped cross-section. The two inner surfaces of the roughly L-shaped guide 65 are positioned such that, when cutting the packaging 80, an upper surface portion 65a contacts the upper surface of the packaging 80 and a side surface portion 65b contacts the side surface to be cut. That is, the longitudinal direction of the guide 65, which is the X-axis direction as shown in Figure 5, is the direction of travel of the blade 62. Furthermore, of the two roughly L-shaped inner surfaces of the guide 65, the side portion 65b, which is positioned to follow the side of the packaging body 80 to be cut (hereinafter also simply referred to as the "cutting surface") when the packaging body 80 is cut, is divided into two by a groove that connects both sides of the side wall, which has the side of the packaging body 80 as one of its main surfaces, in the longitudinal direction of the X-axis, and extends in the vertical direction of the Z-axis.The side portion 65b, which is the side wall of the guide 65 that is divided into two in the longitudinal direction of the X-axis, is formed such that the longitudinal dimension a1 of the side wall in the X-axis direction, which is the destination side of the blade 62, is longer than the longitudinal dimension a2 of the side wall on the source side of the blade 62.In other words, the guide 65 is longer in the direction of movement during cutting.The length of the guide 65 is such that the side of the packaging body 80 being cut is longer on the side where the cutting edge 63 is located than on the side where the cutting edge is located. The blade holder 40 moves while the guide 65 provided on the blade 60 comes into contact with each side and top surface of the packaging 80. Because the guide on the direction of travel is long, even if distortion occurs on the top surface of the packaging 80, the upper surface 65a of the guide 65 has a large contact area, which can absorb the distortion, and the blade tip 63 can stabilize the cutting of the packaging 80. As a result, when the packaging 80 is cut, the packaging 80 is held between the contact surface of the guide 65 with the packaging 80 and the contact surface of the fixed stopper 91 or movable stopper 92 facing the contact surface with the packaging 80, which reduces the effect of distortion on the cut surface of the packaging 80 and allows for stable cutting of the sides of the packaging 80.Furthermore, depending on the shape of the packaging 80 and the surrounding environment of the robot 10, it is also possible to reverse the direction of travel of the blade 62. In other words, preferably the blade tip 63 cuts the side of the packaging 80 toward the a1 side, but depending on the surrounding environment, the blade tip 63 may cut the side of the packaging 80 toward the a2 side.

[0030] As described above, the side of the packaging body 80 is cut as the blade tip 63 moves while it is inserted into the side of the packaging body 80. That is, the blade 60 is inserted into the interior of the packaging body 80 from the side of the packaging body 80, which is the other surface that connects to the top surface of the packaging body 80. Figure 7 shows the orientation of the blade tip 63 to the side of the packaging body 80 at this time. Figure 7 is a schematic diagram illustrating the orientation of the blade tip 63 when the packaging body 80 is cut. As shown in Figure 7, the blade tip 63 is inserted diagonally from below toward upward. That is, the unpacking device 1 inserts the blade tip 63 into the interior of the packaging body 80 from the upper side of the side of the packaging body 80 at an angle. The insertion angle θ of the blade tip 63 at this time is approximately 45 degrees with respect to the horizontal direction, which is the reference. Then, with the blade tip 63 facing toward the top surface of the packaging body 80 inside the packaging body 80, the blade 60 cuts the upper side of the side of the packaging body 80 in a horizontal direction. At this time, the cutting edge 63 inserted from the side of the packaging body 80 faces the upper surface of the packaging body 80 inside the packaging body 80, so it does not damage the articles contained inside the packaging body 80.

[0031] In this embodiment of the unpacking device 1, the insertion angle θ of the blade tip 63 into the side of the packaging body 80 was described as approximately 45 degrees. However, the insertion angle θ of the blade tip 63 into the side of the packaging body 80 can be changed as appropriate, as long as the above-mentioned effects are achieved. For example, as shown in Figure 6, the insertion angle θ of the blade tip 63 into the side of the packaging body 80 can be appropriately adjusted between 0 and 45 degrees by providing a rail 66 on the blade portion 60 for changing the installation angle of the blade 62. The angle of the blade tip 63 can also be changed at any time during cutting of the side, corresponding to the positional relationship of the items stored in the packaging body 80.

[0032] Furthermore, in the unpacking device 1 of this embodiment, the length to which the blade tip 63 is inserted into the side of the packaging body 80, that is, the amount of insertion of the blade tip 63 into the side of the packaging body 80, can be appropriately changed. As described above, the insertion amount of the blade tip 63 can also be changed in accordance with the positional relationship of the articles stored in the packaging body 80. In this case, the insertion amount can be reduced in areas of the packaging body 80 where damage to the articles is not desired, and increased to make it easier to cut the sides, thereby adjusting the efficiency of removing the stored articles and the top surface of the packaging body 80.

[0033] As mentioned above, the blade portion 60 is connected to the blade holder portion 40 by the first elastic body 41. The blade portion 60 can also rotate horizontally around the rotation axis of the first shaft portion 42 of the blade holder portion 40. Therefore, when the blade portion 60 rotates around the first shaft portion 42 of the blade holder portion 40 due to the reaction force when the guide 65 contacts the side surface of the packaging body 80, the blade portion 60 is biased by the first elastic body 41 and tilts in a direction perpendicular to the direction of movement. That is, the cutting edge 63 tilts due to the first elastic body 41. This reduces the load on the blade 62 and can reduce or suppress wear on the blade 62. In addition, this can reduce the amount of chips generated when cutting the side surface of the packaging body 80.

[0034] As described above, when the robot 10 operates with the blade tip 63 penetrating the side of the packaging 80, the blade holder 40 fixed to the tip of the robot 10 moves in a substantially horizontal direction along the corners of the packaging 80, which are the connection points between the top surface of the packaging 80 and each side of the packaging 80. That is, the blade holder 40 moves along each side of the top surface of the packaging 80, in other words, along the outer edge of the top surface, in the space around the top surface of the packaging 80, and also moves in a substantially horizontal direction along each side of the packaging 80. At this time, the blade 60 follows the blade holder 40 and moves in a substantially horizontal direction. As a result, the blade tip 63 moves in a substantially horizontal direction with the blade tip 63 penetrating the side of the packaging 80, and cuts the side of the packaging 80 in a substantially horizontal direction. The course of movement of the blade tip 63 at this time, that is, the trajectory of the blade tip 63, is shown in Figure 8. Figure 8 is a schematic diagram illustrating the trajectory of the blade tip 63 when cutting the packaging 80. As mentioned above, the cutting edge 63 moves in a specified order to multiple points in the three-dimensional Cartesian coordinate system that are set as the destination. The trajectory in Figure 8 shows the cutting edge 63 moving from the state in Figure 1 towards the cutting start point 200. In doing so, the cutting edge 63 passes through the trajectory point 210 before reaching the cutting start point 200. After passing the cutting start point 200, the cutting edge 63 moves towards the trajectory point 220a while cutting the first side surface 80a. After passing the trajectory point 220a, the cutting edge 63 moves in a circular arc towards the next trajectory point 220b, inserting itself from the first side surface 80a to the second side surface 80b. After that, the cutting edge 63 cuts the other sides, and when it reaches the trajectory point 230 of the fourth side surface 80d, it passes through the cutting start point 200 while drawing a circular arc from the fourth side surface 80d towards the first side surface 80a, cutting the edge where the fourth side surface 80d and the first side surface 80a are connected. The four sides of the packaging 80 are cut by scanning the cutting edge 63 so that the cutting start point 200 serves as both the start and end point. Before cutting the packaging 80 in this way, the trajectory that the cutting edge 63 will pass through is set. That is, multiple points set as destinations for the cutting edge 63 in a three-dimensional Cartesian coordinate system become the points that the cutting edge 63 will pass through. As shown in Figure 8, all of these points are set inside the side walls of the packaging 80.Furthermore, when the blade holder 40 moves around the corners of the upper surface of the packaging body 80, that is, when it moves around the corners where the sides of the packaging body 80 meet, the distance between the cutting edge 63 of the blade 60 and the insertion point of the cutting edge 63 into the packaging body 80 is longer than the distance between the cutting edge 63 of the blade 60 and the insertion point of the cutting edge 63 into the packaging body 80 when it moves along the edges of the upper surface of the packaging body 80, that is, when it moves along the sides of the packaging body. In other words, at the corners of the packaging body 80, the blade 62 passes further inside the packaging body 80. As a result, when the unpacking device 1 rotates to cut the corners of the packaging body 80, it is possible to cut the corners by passing the blade 60 as if pushing it inward. As a result, the cutting time of the packaging body 80 is shortened, and the amount of chips generated when cutting the packaging body 80 can be reduced. Furthermore, when the cutting edge 63 moves in an arc shape and switches the cutting surface from the first side 80a to the second side 80b, the upper surface 65a of the guide 65 scans while in contact with the upper surface of the packaging 80, allowing for a smooth switch of the cutting surface. In other words, the cutting edge 63 can be scanned without needing to adjust the height each time the cutting surface is switched. Moreover, when setting the trajectory for the cutting edge 63 to pass through, the trajectory may be set so that the side surface 65b of the guide 65 contacts the side of the packaging 80. As a result, the force applied by the stretched first elastic body 41 trying to return to its original position presses the side surface 65b toward the side of the packaging 80. As a result, the blade 62 is pressed against the side of the packaging 80 without leaving it, making it possible for the blade 62 to cut the side of the packaging 80.

[0035] Furthermore, the blade holder 40 moves around the space surrounding the first surface (top surface) of the packaging body 80 so that the blade 60 continues to contact the packaging body 80 until it reaches the cutting start position again. In other words, the unpacking device 1 cuts the packaging body 80 in a single continuous line, as shown in Figure 8. This makes it possible to cut the corners where the sides of the packaging body 80 are joined together. As a result, the unpacking device 1 is able to cut the packaging body 80 in a single continuous line, and the cutting start position is completed in one step, thus shortening the cutting time compared to cutting each of the four sides of the packaging body 80 one by one. In other words, for example, when cutting one side at a time, it is necessary to align the cutting edge 63 so that the position where the cutting edge 63 is away from the first side surface 80a is aligned with the position where cutting of the second side surface 80b begins. However, in the present invention, the cutting edge 63 is continuously inserted when the surface being cut changes from the first side surface 80a to the second side surface 80b, thus reducing the step of adjusting the insertion position of the cutting edge 63 each time the side being cut changes. Since the cutting edge 63 is not removed or inserted, and the insertion position of the cutting edge 63 is not adjusted for each cut surface, the generation of chips can also be reduced.

[0036] The preferred order for cutting the sides of the packaging 80 is as shown in Figure 8, starting from the end of the side facing the robot 10, in the direction upstream of the conveyor belt of the belt conveyor device on which the packaging 80 is placed, in other words, the end in the direction of the conveyor source of the packaging 80, cutting toward the first side 80a of the packaging 80 in the X-axis direction, and when a corner is reached, the corner where the sides are joined is cut while rotating around the corner in the manner described above, cutting the next side, and so on, until the entire circumference of the packaging 80 is completed, and the sides of the packaging 80 are cut in a nearly horizontal direction back to the starting position, thereby cutting the sides of the packaging 80 in a single continuous line as described above. Alternatively, the end where the surfaces of the packaging 80 are joined may be selected as the starting position for cutting. This can suppress distortion and damage to the packaging 80 caused by contact between the guide 65 and the joining part of the surface of the packaging 80 that may occur during cutting.

[0037] According to the embodiments of the present invention described above, the following effects and advantages are achieved.

[0038] (1) The unpacking device 1 is a device for unpacking a package 80 and comprises a robot 10 and a cutter hand 20 attached to the tip of the robot 10. The cutter hand 20 has a blade portion 60 including a blade 62 for cutting the package 80 and a blade holder portion 40 for holding the blade portion 60. The blade holder portion 40 moves in the space around the first surface (top surface) of the package 80, extending in both a second direction that is not parallel to the first direction (vertical direction), which is the axial direction of the first shaft portion 42 of the blade holder portion 40, and a third direction that is perpendicular to the second direction, while keeping the blade portion 60 in contact with the package 80. The distance between the cutting edge 63 of the blade portion 60 and the insertion position of the cutting edge 63 into the package 80 when the blade holder portion 40 moves along a corner of the first surface is longer than the distance between the cutting edge 63 of the blade portion 60 and the insertion position of the cutting edge 63 into the package 80 when it moves along an edge of the first surface. In other words, at the corners of the packaging 80, the blade 62 passes further inside the packaging 80. In this way, when the unpacking device 1 rotates to cut the corners of the packaging 80, it pushes the blade 60 inward as it passes, enabling it to cut the corners. As a result, the cutting time for the packaging 80 is shortened, and the amount of chips generated when cutting the packaging 80 is reduced.

[0039] (2) The blade portion 60 is equipped with a guide 65 that is movable along the surface of the packaging body 80. The blade portion 60 is also connected to the blade holder portion 40 by a first elastic body 41. Furthermore, the blade portion 60 is rotatable around the first shaft portion 42 of the blade holder portion 40, with the first direction as its axial direction. The blade holder portion 40 moves while the guide 65 is in contact with the packaging body 80. In this way, the blade portion 60 rotates around the axis of the blade holder portion 40 due to the reaction force when the guide 65 contacts the side surface of the packaging body 80, causing the blade portion 60 to tilt in a direction perpendicular to the direction of movement. That is, the elastic body 41 causes the cutting edge 63 to tilt. In this way, the unpacking device 1 can reduce the load on the blade 62 and suppress wear of the blade 62. In addition, the unpacking device 1 can reduce the amount of chips generated when cutting the side surface of the packaging body 80.

[0040] (3) The guide 65 is formed to be long in the direction of movement during cutting. This reduces the effect of distortion on the cut surface of the packaging 80 when the packaging 80 is cut. As a result, the unpacking device 1 can stably cut the side of the packaging 80.

[0041] (4) The blade holder 40 moves around the space surrounding the first surface (top surface) of the packaging body 80 so that the blade 60 continues to contact the packaging body 80 until the blade 60 reaches the cutting start position again. In other words, the unpacking device 1 cuts the packaging body 80 in a single continuous line. In this way, it becomes possible to cut the corners where the sides of the packaging body 80 are joined together. As a result, the unpacking device 1 is able to cut the packaging body 80 in a single continuous line, and the cutting start position is completed in one step, so the cutting time can be shortened compared to when the four sides of the packaging body 80 are cut one by one.

[0042] (5) The blade portion 60 is inserted from another side (side) of the packaging body 80 that is connected to the first surface (top surface), and the cutting edge 63 of the blade portion 60 cuts the packaging body 80 with the cutting edge facing the first surface. That is, the unpacking device 1 inserts the cutting edge 63 into the inside of the packaging body 80 from the side of the packaging body 80 at an angle. At this time, the cutting edge 63 inserted from the side of the packaging body 80 is facing the top surface of the packaging body 80 inside the packaging body 80, so the unpacking device 1 does not damage the articles contained inside the packaging body 80.

[0043] (6) The blade holder 40 is equipped with a second elastic body 43 that is mounted so as to be extendable and retractable in the vertical direction. That is, the blade holder 40 has the elastic body 43 mounted in the vertical direction. In this way, the unpacking device 1 can appropriately follow the vertical distortion of the shape of the packaging body 80 when cutting the packaging body 80, thereby stabilizing the cutting of the packaging body 80.

[0044] (7) The blade 62 is an ultrasonic cutter. In this way, the unpacking device 1 experiences less wear on the blade 62 when cutting the package 80. Also, the unpacking device 1 generates less chips when cutting the sides of the package 80.

[0045] (8) The blade holder 40 is connected to the robot 10 and moves with the operation of the robot 10. That is, the blade holder 40 is connected to the robot 10 and operates. In this way, the unpacking device 1 can automatically unpack the packaged body 80 without human intervention.

[0046] It should be noted that the present invention is not limited to the embodiments described above, and can be implemented using any components without departing from the spirit of the invention.

[0047] For example, to further automate the unpacking process, sensors may be attached to the unpacking device 1 to detect the size of the package 80 and the position of its corners.

[0048] Furthermore, for example, a belt conveyor device or workbench on which the packaged body 80 is placed during the unpacking process may also be controlled integrally with the unpacking device 1. In that case, for example, the operation of the movable stopper 92 may also be subject to control. Also, for example, in order to absorb the distortion of the packaged body 80, the height of the cutting position on the side of the packaged body 80 may be appropriately adjusted by raising and lowering the placement surface 90 of the packaged body 80 on the belt conveyor device or workbench, thereby enabling the side of the packaged body 80 to be cut stably in a substantially horizontal direction without moving the position of the blade 62 in the vertical direction.

[0049] The embodiments and modifications described above are merely examples, and the present invention is not limited to these, as long as the features of the invention are not impaired. Furthermore, although various embodiments and modifications have been described above, the present invention is not limited to these. Other embodiments conceivable within the scope of the technical idea of ​​the present invention are also included within the scope of the present invention. [Explanation of Symbols]

[0050] 1: Unpacking device 10: Robots 20: Cutter Hand 40:Blade holding part 41: First elastic body 42: First shaft 43: Second elastic body 60: Blade part 61: Second shaft 62: Blade (ultrasonic cutter) 63: Blade tip 64: Cutter holder 65: Guide 80: Packaging (cardboard box) 90: Mounting surface 91: Fixed stopper 92: Movable stopper

Claims

1. An unpacking device for unpacking a package, The system comprises a robot and a cutter hand attached to the tip of the robot, The cutter hand has a blade portion including a blade for cutting the packaging body, and a blade holding portion for holding the blade portion. The blade holder moves in the space around the first surface of the packaging body, extending in both a second direction that is non-parallel to the first direction which is the axial direction of the first shaft of the blade holder, and a third direction that is perpendicular to the second direction, while the blade portion is in contact with the packaging body. When the blade holding portion moves around the corner where one side of the packaging body and another side different from the first side join, the distance between the cutting edge of the blade portion and the position where the cutting edge is inserted into the packaging body is longer than the distance between the cutting edge of the blade portion and the position where the cutting edge is inserted into the packaging body when moving along the first side or the other side. The cutting edge rotates as it is inserted from one side to the other side and moves forward. Unpacking device.

2. In the unpacking device according to claim 1, The aforementioned blade portion is The package is equipped with a guide that is movable along the surface of the package, The blade holding portion is connected to the first elastic body, The blade holding portion is rotatable around the first shaft portion with the first direction as the axial direction, The blade holding portion moves while the guide is in contact with the packaging body. Unpacking device.

3. In the unpacking device according to claim 2, The aforementioned guide is formed to have a long length in the direction of movement during cutting in the unpacking device.

4. In the unpacking device according to claim 1, The blade holding portion moves in the space surrounding the first surface of the packaging body so that the blade portion continues to contact the packaging body until the blade portion reaches the cutting start position again.

5. In the unpacking device according to claim 1, An unpacking device wherein the blade portion is inserted from another side of the packaging body connected to the first surface, and cuts the packaging body with the cutting edge of the blade portion facing the first surface.

6. In the unpacking device according to claim 1, The unpacking device comprises a blade holder equipped with a second elastic body that is vertically expandable and contractible.

7. In the unpacking device according to claim 1, The aforementioned blade is an ultrasonic cutter, in the unpacking device.

8. In the unpacking device according to claim 1, The blade holder is connected to the robot and moves in accordance with the robot's movements, forming an unpacking device.

9. A cutter hand having the blade portion and blade holder portion as described in claim 2.

10. An unpacking method for unpacking a package using an unpacking device comprising a robot and a cutter hand attached to the tip of the robot, The cutter hand has a blade portion including a blade for cutting the packaging body, and a blade holding portion for holding the blade portion. The blade holder moves in the space around the first surface of the packaging body, extending in both a second direction that is non-parallel to the first direction which is the axial direction of the first shaft of the blade holder, and a third direction that is perpendicular to the second direction, while the blade portion is in contact with the packaging body. When the blade holding portion moves around the corner where one side of the packaging body and another side different from the first side join, the distance between the cutting edge of the blade portion and the position where the cutting edge is inserted into the packaging body is longer than the distance between the cutting edge of the blade portion and the position where the cutting edge is inserted into the packaging body when moving along the first side or the other side. The cutting edge rotates as it is inserted from one side to the other side and moves forward. Unpacking instructions.

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