Sheet holding down system

Abstract

To automate the operation to hold down an article received in a box by a sheet.SOLUTION: A sheet holding down system 1 comprises a hand 20, a sensor 30 and a controller 40. The hand 20 holds a sheet 70 to cover from an upper side Z1 in an up-down direction Z an article 60 received in a box 50 opening at a top end 51 on the upper side Z1 in the up-down direction Z and moves the sheet 70 to a lower side Z2 in the up-down direction Z, thereby holding down the sheet 70 onto the article 60. The sensor 30 detects a reaction force Rz toward the upper side Z1 in the up-down direction Z which the hand 20 undergoes from the article 60 through the sheet 70. The controller 40 controls the movement in the up-down direction Z of the hand 20 based on the reaction force Rz.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a sheet hold-down system. [Background technology]

[0002] A method is known in which a cushioning material is filled in the gap between the box and the object to prevent the object from moving inside the box and being damaged. Patent Document 1 also discloses a method of holding down the object with a sheet to prevent the object from moving inside the box and being damaged. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-115741 A Summary of the Invention [Problem to be solved by the invention]

[0004] The sheet according to Patent Document 1 is basically intended to be used manually, and therefore the task of pressing down the items contained in the box with the sheet is performed manually by a worker.

[0005] From the viewpoint of labor saving, it is desirable to automate the task of pressing down the items contained in the box with a sheet. However, since the shape and size of the items change each time, it is difficult to automate the task of pressing down the items contained in the box with a sheet.

[0006] The present disclosure has been made in consideration of the above points, and has an object to automate the task of pressing down items contained in a box with a sheet. [Means for solving the problem]

[0007] The sheet holding system of the present disclosure includes a hand that holds a sheet covering an object contained in a box having an open end in a first direction from one side in the first direction and holds the sheet against the object by moving the sheet in the other side in the first direction, a sensor that detects a reaction force in one side of the first direction that the hand receives from the object via the sheet, and a controller that controls the movement of the hand in the first direction based on the reaction force.

[0008] According to this sheet holding down system, the controller controls the movement of the hand in the first direction based on a reaction force in one of the first directions that the hand receives from the object via the sheet. Therefore, even if the shape or size of the object inside the box changes from time to time, the hand can hold the sheet against the object inside the box with an appropriate force.

[0009] According to this sheet pressing system, the task of pressing down items contained in a box with a sheet can be automated.

[0010] In one embodiment, the controller stops or slows down the movement of the hand in the other of the first directions when the reaction force becomes equal to or greater than a first predetermined value.

[0011] This configuration can prevent the hand from pressing the sheet against the article with too much force.

[0012] In one embodiment, the hand is rotatable about an axis in a second direction according to a reaction moment about an axis in a second direction intersecting the first direction that the hand receives from the article via the sheet.

[0013] According to this configuration, the sheet conforms to the shape of the article, which is advantageous in reducing the gap between the article and the sheet.

[0014] In one embodiment, the sensor senses the reaction moment.

[0015] This configuration is advantageous in controlling the rotation of the hand based on the reaction moment about the axis in the second direction.

[0016] In one embodiment, the controller stops rotation of the hand about the axis in the second direction when the reaction moment becomes equal to or less than a second predetermined value.

[0017] This configuration is advantageous in preventing the hand from rotating too much about the axis in the second direction, which would otherwise cause the sheet to be pushed excessively against the article.

[0018] In one embodiment, the sheet holding down system includes a multi-axis robot arm that moves the hand, the multi-axis robot arm moving the hand in the first direction and rotating the hand about an axis in the second direction.

[0019] According to this configuration, the multi-axis robot arm can suitably move the hand in the first direction and can suitably rotate the hand about an axis in the second direction.

[0020] In one embodiment, the hand holds a surface of the sheet facing one side in the first direction.

[0021] This configuration is advantageous in preventing the hand from coming into contact with the inner wall of the box, as compared to a case in which the hand holds the peripheral edge of the sheet.

[0022] In one embodiment, the hand adheres to a surface of the sheet facing one side in the first direction by negative pressure.

[0023] This configuration makes it easy to hold the sheet with the hand.

[0024] In one embodiment, the controller is switchable between a first control mode in which the hand is moved in the other direction of the first direction without based on the reaction force, and a second control mode in which the hand is moved in the other direction of the first direction based on the reaction force.

[0025] With this configuration, the first control mode allows the hand to be quickly moved in the other first direction without being based on a reaction force in one side of the first direction, and the second control mode allows the hand to be carefully moved in the other first direction based on a reaction force in one side of the first direction.

[0026] In one embodiment, the controller uses the first control mode to move the hand in the other direction of the first direction without using the reaction force before the hand reaches a predetermined position in the first direction, and uses the second control mode to move the hand in the other direction of the first direction based on the reaction force after the hand reaches the predetermined position.

[0027] According to this configuration, in the second control mode after the hand reaches a predetermined position, the hand must be moved based on a reaction force, and therefore the hand can only be moved at a low speed. On the other hand, in the first control mode before the hand reaches a predetermined position, the hand can be moved at high speed, since it can be moved without being based on a reaction force. By quickly moving the hand in the first control mode and then switching to the second control mode, the hand movement time can be shortened overall.

[0028] In one embodiment, a printed material insertion mechanism is provided that inserts a printed material indicating information about the item into the sheet from one of the first directions after the sheet is pressed against the item by the hand.

[0029] With this configuration, the printed matter is less likely to be lost, compared to when cushioning material is filled into the gap between the box and the article.

[0030] In one embodiment, the article comprises a pharmaceutical agent.

[0031] This configuration is advantageous in avoiding damage to the medicine.

[0032] In one embodiment, the first directions are vertical directions, one of the first directions being upward and the other of the first directions being downward.

[0033] According to this configuration, it is easier to handle than when the first direction is the horizontal direction. Effect of the Invention

[0034] According to the present disclosure, it is possible to automate the task of pressing down items contained in a box with a sheet. [Brief description of the drawings]

[0035] [Figure 1] FIG. 1 shows a box, an article, and a sheet according to the first embodiment. [Diagram 2] FIG. 2 shows a seat according to the first embodiment. [Diagram 3] FIG. 3 shows the sheet pressing system according to the first embodiment. [Figure 4] FIG. 4 shows the control of the vertical movement of the hand in the first embodiment. [Diagram 5] FIG. 5 shows the control of rotation of the hand around a horizontal axis in the first embodiment. [Figure 6] FIG. 6 shows a control flow for the movement and rotation of the hand in the first embodiment. [Figure 7] FIG. 7 shows the control of the hand in the second embodiment. [Figure 8] FIG. 8 shows a printed material input mechanism according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0036] Hereinafter, the embodiments of the present disclosure will be described in detail with reference to the drawings. The following description of the preferred embodiments is merely illustrative in nature and is not intended to limit the present disclosure, its application, or its uses.

[0037] First Embodiment (Box, item and sheet) 1 shows a box 50, an article 60, and a sheet 70 according to the first embodiment. The box 50 has a rectangular parallelepiped shape. The box 50 is a packaging box. The box 50 is made of, for example, cardboard, thick paper, or resin.

[0038] The box body 50 extends in a vertical direction Z as a first direction. The box body 50 extends in a horizontal direction H as a second direction. The horizontal direction H intersects (more specifically, is perpendicular to) the vertical direction Z. The horizontal direction H is made up of a front-rear direction X and a left-right direction Y that intersect (more specifically, are perpendicular to) each other.

[0039] The box body 50 has an upper end 51 that is open on the upper side Z1, which is one side of the vertical direction Z. In other words, an opening 51a is provided at the upper end 51 of the box body 50. A lid 53 is provided at the upper end 51 of the box body 50. The lid 53 covers the opening 51a. The box body 50 is placed on a foundation on a lower side Z2, which is the other side of the vertical direction Z.

[0040] The box 50 contains an article 60. The article 60 is placed on the inner bottom surface of the box 50. The article 60 includes a medicine 61 and a medicine bag 62. The medicine 61 is placed in the medicine bag 62.

[0041] 2 shows the sheet 70. The sheet 70 is made of cardboard or resin. The sheet 70 includes a main body 71 and four locking pieces 72. The main body 71 is rectangular. The four locking pieces 72 are connected to the four peripheral edges of the main body 71 via fold lines 73. The locking pieces 72 extend outward in the horizontal direction H from the peripheral edges of the main body 71.

[0042] Two holes 74 are formed in the main body 71. The holes 74 are provided for an operator to hook his / her fingers. As will be described later, in this embodiment, the operation of holding down the article 60 contained in the box 50 with the sheet 70 is automated, so the holes 74 are not used in principle.

[0043] The locking piece 72 is composed of a plurality of flaps 72a. The plurality of flaps 72a are arranged at intervals along the periphery of the main body portion 71. The flaps 72a are folded independently of each other.

[0044] 1, the outer dimensions of the entire sheet 70, which is the combination of the main body 71 and the locking pieces 72, are larger than the inner dimensions of the box 50. The outer dimensions of the main body 71 alone are smaller than the inner dimensions of the box 50.

[0045] The sheet 70 covers the article 60 from above Z1 in the up-down direction Z inside the box 50. When the sheet 70 is placed inside the box 50, the locking pieces 72 bend upward Z1 at the fold line 73 relative to the main body 71 and stand up. The locking pieces 72 are locked to the inner wall 52 of the box 50, so that the sheet 70 is fixed inside the box 50. The sheet 70 restricts movement of the article 60 inside the box 50, and fixes the article 60 inside the box 50.

[0046] (Sheet holding system) 3 shows the sheet pressing system 1 according to the first embodiment. The sheet pressing system 1 includes a multi-axis robot arm 10, a hand 20, a sensor 30, and a controller 40.

[0047] The multi-axis robot arm 10 is a six-axis articulated robot arm. The multi-axis robot arm 10 moves the hand 20 in six directions. The multi-axis robot arm 10 moves the hand 20 in a total of three directions, the up-down direction Z and the horizontal direction H (the front-back direction X and the left-right direction Y). The multi-axis robot arm 10 rotates the hand 20 in a total of three directions, around an axis in the up-down direction Z and around an axis θh in the horizontal direction H (the front-back direction X and the left-right direction Y).

[0048] The hand 20 is connected to the tip of the multi-axis robot arm 10. The hand 20 includes a frame 21, a connector 22, and four suction pads 23. The frame 21 is in the shape of a rectangular plate. The connector 22 is provided on the upper surface of the frame 21. The upper surface of the frame 21 faces upward Z1 in the vertical direction Z. The connector 22 is connected to the tip of the multi-axis robot arm 10.

[0049] The four suction pads 23 are provided at the four corners of the lower surface of the frame 21. The lower surface of the frame 21 faces downward Z2 in the up-down direction Z. A vacuum pump (not shown) is connected to the suction pads 23.

[0050] The hand 20 holds the sheet 70. The hand 20 holds an upper surface 71a of a main body portion 71 of the sheet 70. The upper surface 71a of the sheet 70 is the surface of the sheet 70 facing upward Z1 in the vertical direction Z. The suction pad 23 of the hand 20 adsorbs the upper surface 71a of the sheet 70 by negative pressure. In detail, the suction pad 23 of the hand 20 adsorbs portions of the upper surface 71a of the main body portion 71 of the sheet 70 that are slightly inward from the four corners by negative pressure.

[0051] The negative pressure refers to a pressure lower than the pressure in the space (for example, a room) in which the sheet pressing system 1 exists, or a pressure lower than atmospheric pressure.

[0052] The connector 22 of the hand 20 is connected to the tip of the multi-axis robot arm 10 so as to be rotatable in a total of three directions: around an axis in the up-down direction Z and around an axis θh in the horizontal direction H (front-back direction X and left-right direction Y). The hand 20 can freely rotate with respect to the multi-axis robot arm 10. The orientation of the hand 20 with respect to the multi-axis robot arm 10 can freely be changed.

[0053] The hand 20 moves the held sheet 70 downward Z2 in the vertical direction Z, thereby inserting the sheet 70 into the box 50 through the opening 51a at the upper end 51 of the box 50. The hand 20 presses the sheet 70 against the article 60 by moving the sheet 70 downward Z2 in the vertical direction Z.

[0054] Here, the top surface of the article 60 does not extend straight in the horizontal direction H, but extends obliquely relative to the horizontal direction H. When the sheet 70 comes into contact with the upper end 60a of the article 60 in the box 50, the hand 20 receives a reaction force Rz from the article 60 via the sheet 70 in the upward / downward direction Z1.

[0055] When the sheet 70 comes into contact with the upper end 60a of the article 60 in the box 50, the hand 20 may receive a reaction force in the horizontal direction H (the front-back direction X and the left-right direction Y) from the article 60 via the sheet 70.

[0056] When the sheet 70 comes into contact with the upper end 60a of the article 60 in the box 50, the hand 20 may receive a reaction moment from the article 60 through the sheet 70 about an axis in the vertical direction Z. When the sheet 70 comes into contact with the upper end 60a of the article 60 in the box 50, the hand 20 receives a reaction moment Mθh from the article 60 through the sheet 70 about an axis θh in the horizontal direction H.

[0057] As described above, the hand 20 can freely rotate (wrist free) with respect to the multi-axis robot arm 10. Therefore, the hand 20 can rotate around the axis θh in the horizontal direction H in accordance with the reaction moment Mθh around the axis θh in the horizontal direction H that the hand 20 receives from the article 60 via the sheet 70.

[0058] The sensor 30 is a known six-axis force sensor. The sensor 30 is provided between the multi-axis robot arm 10 and the hand 20. The sensor 30 is, for example, a strain gauge type, a piezoelectric type, an optical type, or a capacitance type. The sensor 30 detects a reaction force Rz in the upward direction Z1 in the vertical direction Z that the hand 20 receives from the article 60 via the sheet 70. The sensor 30 also detects a reaction force in the horizontal direction H (front-back direction X and left-right direction Y) that the hand 20 receives from the article 60 via the sheet 70.

[0059] The sensor 30 detects a reaction moment about an axis in the vertical direction Z that the hand 20 receives from the article 60 via the sheet 70. The sensor 30 also detects a reaction moment Mθh about an axis θh in the horizontal direction H that the hand 20 receives from the article 60 via the sheet 70.

[0060] The controller 40 is configured with, for example, a CPU (Central Processing Unit) or an MCU (Micro Controller Unit). The controller 40 executes a predetermined program in the CPU or MCU. The program is stored in a memory.

[0061] The controller 40 controls the movement of the hand 20 by the multi-axis robot arm 10, the rotation of the hand 20 by the multi-axis robot arm 10, and the suction of the sheet 70 by the suction pad 23 of the hand 20, etc.

[0062] The controller 40 controls the movement of the hand 20 in the vertical direction Z based on a reaction force Rz in the upward direction Z1 in the vertical direction Z that the hand 20 receives from the article 60 via the sheet 70. The controller 40 controls the rotation of the hand 20 about an axis θh in the horizontal direction H based on a reaction moment Mθh about an axis θh in the horizontal direction H that the hand 20 receives from the article 60 via the sheet 70.

[0063] (Control of hand movement up and down) FIG. 4 shows the control of the up-and-down movement in the Z direction of the hand 20. For simplicity, the case where the upper surface of the article 60 extends straight in the horizontal direction H is illustrated. By the controller 40 controlling the suction pad 23, the hand 20 sucks and holds the upper surface 71a of the sheet 70.

[0064] By the controller 40 controlling the multi-axis robot arm 10, the hand 20 holding the sheet 70 moves downward in the Z direction to Z2 and is inserted into the box body 50 through the opening 51a at the upper end 51 of the box body 50.

[0065] When the hand 20 holding the sheet 70 moves further downward to Z2, the sheet 70 comes into contact with the upper surface of the article 60 inside the box body 50. When the sheet 70 comes into contact with the upper surface of the article 60 inside the box body 50, the sensor 30 detects the reaction force Rz in the upward Z1 direction in the Z direction that the hand 20 receives from the article 60 through the sheet 70.

[0066] The hand 20 presses the sheet 70 against the article 60 by moving the sheet 70 downward in the Z direction to Z2.

[0067] When the reaction force Rz in the upward Z1 direction in the Z direction that the hand 20 receives from the article 60 through the sheet 70 becomes equal to or greater than the first predetermined value A1, the controller 40 stops or decelerates the downward movement of the hand 20 in the Z direction to Z2. The speed Vb of the hand 20 moving downward to Z2 when the reaction force Rz in the upward Z1 direction is equal to or greater than the first predetermined value A1 is smaller than the speed Va of the hand 20 moving downward to Z2 when the reaction force Rz in the upward Z1 direction is less than the first predetermined value A1 (Vb < Va). Alternatively, the speed Vb of the hand 20 moving downward to Z2 when the reaction force Rz in the upward Z1 direction is equal to or greater than the first predetermined value A1 is zero (Vb = 0). As an example, the first predetermined value A1 is, for example, 10 [N].

[0068] In this example, since the top surface of the article 60 extends straight in the horizontal direction H, even if the sheet 70 comes into contact with the top surface of the article 60 inside the box body 50, the hand 20 does not receive a reaction moment Mθh of θh around the axis of the horizontal direction H from the article 60 via the sheet 70.

[0069] The controller 40 controls the suction pad 23, whereby the hand 20 releases the hold on the upper surface 71a of the sheet 70. The controller 40 controls the multi-axis robot arm 10, whereby the hand 20 moves upward Z1 in the vertical direction Z and goes out from inside the box 50 to the outside through the opening 51a at the upper end 51 of the box 50.

[0070] (Control of hand rotation around horizontal axis) 5 shows control of rotation θh around an axis in the horizontal direction H of the hand 20 in the first embodiment. Note that this illustrates a case where the top surface of the article 60 does not extend straight in the horizontal direction H, but extends obliquely relative to the horizontal direction H. In the following description of FIG. 5, matters similar to those in the description of FIG. 4 may be omitted.

[0071] As described above, when the reaction force Rz in the upward direction Z1 that the hand 20 receives from the article 60 via the sheet 70 becomes equal to or greater than the first predetermined value A1, the movement of the hand 20 in the downward direction Z2 is stopped or decelerated.

[0072] When the sheet 70 comes into contact with the upper end 60a of the article 60 in the box 50, the hand 20 receives a reaction moment Mθh of θh around an axis in the horizontal direction H from the upper end 60a of the article 60 via the sheet 70.

[0073] The hand 20 can freely rotate with respect to the multi-axis robot arm 10. Therefore, the hand 20 rotates around the axis θh in the horizontal direction H so as to follow the shape of the upper surface of the article 60 in accordance with a reaction moment Mθh around the axis θh in the horizontal direction H that the hand 20 receives from the upper end portion 60a of the article 60 via the sheet 70.

[0074] In particular, when the hand 20 is moving downward Z2, the rotation of the hand 20 about the axis θh in the horizontal direction H is promoted.

[0075] A reaction moment Mθh about an axis θh in the horizontal direction H that the hand 20 receives from the upper end 60a of the article 60 via the sheet 70 becomes smaller as the hand 20 rotates about the axis θh in the horizontal direction H. In addition, as the hand 20 rotates about the axis θh in the horizontal direction H (as the reaction moment Mθh about the axis θh in the horizontal direction H becomes smaller), the gap C between the upper surface of the article 60 and the lower surface of the sheet 70 becomes smaller.

[0076] The controller 40 stops the rotation of the hand 20 about the axis θh in the horizontal direction H when the reaction moment Mθh about the axis θh in the horizontal direction H that the hand 20 receives from the article 60 via the sheet 70 becomes equal to or less than the second predetermined value A2. For example, the rotation of the hand 20 about the axis θh in the horizontal direction H is stopped by a chuck mechanism provided in the multi-axis robot arm 10. As an example, the second predetermined value A2 is an arbitrary value between 0.1 [N·m] and 1 [N·m].

[0077] (Hand movement and rotation control flow) 6 shows a control flow of the movement and rotation of the hand 20 by the controller 40. Starting from the start, in a first step S1, the controller 40 controls the suction pad 23 to cause the hand 20 to suction and hold the upper surface 71a of the sheet 70 by negative pressure.

[0078] Next, in a second step S2, the controller 40 controls the multi-axis robot arm 10 so that the hand 20 holding the sheet 70 moves downward Z2 in the vertical direction Z and is inserted into the box 50 through the opening 51a of the upper end 51 of the box 50. Then, the hand 20 presses the sheet 70 against the article 60 inside the box 50.

[0079] Next, in the third step S3, by the controller 40 monitoring the sensor 30, the sensor 30 detects the reaction force Rz in the upward direction Z1 of the vertical direction Z that the hand 20 receives from the article 60 via the sheet 70. The reaction force Rz detected by the sensor 30 is input to the controller 40.

[0080] Next, in the fourth step S4, the controller 40 determines whether the reaction force Rz detected by the sensor 30 is equal to or greater than a first predetermined value A1 (Rz≧A1?). If it is determined that the reaction force Rz is equal to or greater than the first predetermined value A1 (Rz≧A1), the process proceeds to the fifth step S5. If it is determined that the reaction force Rz is less than the first predetermined value A1 (Rz<A1), the process returns to the third step S3.

[0081] In the fifth step S5, by the controller 40 controlling the multi-axis robot arm 10, the downward movement of the hand 20 in the vertical direction Z to Z2 is stopped or decelerated.

[0082] Next, in the sixth step S6, by the controller 40 monitoring the sensor 30, the sensor 30 detects the reaction moment Mθh about the axis of the horizontal direction H that the hand 20 receives from the article 60 via the sheet 70. The reaction moment Mθh detected by the sensor 30 is input to the controller 40.

[0083] Next, in the seventh step S7, the controller 40 determines whether the reaction moment Mθh detected by the sensor 30 is equal to or less than a second predetermined value A2 (Mθh≦A2?). If it is determined that the reaction moment Mθh is equal to or less than the second predetermined value A2 (Mθh≦A2), the process proceeds to the eighth step S8. If it is determined that the reaction moment Mθh is greater than the second predetermined value A2 (Mθh>A2), the process returns to the sixth step S6.

[0084] In the eighth step S8, by the controller 40 controlling the multi-axis robot arm 10, the rotation of the hand 20 about the axis of the horizontal direction H by θh is stopped.

[0085] Next, in a ninth step S9, the controller 40 controls the suction pads 23 so that the hand 20 releases the suction hold on the upper surface 71a of the sheet 70.

[0086] Next, in a tenth step S10, the controller 40 controls the multi-axis robot arm 10 to move the hand 20 upward Z1 in the vertical direction Z, and moves from inside the box 50 to the outside through the opening 51a of the upper end 51 of the box 50. Then, the hand 20 reaches the end.

[0087] (Action and effect) According to the sheet holding system 1 of this embodiment, the controller 40 controls the movement of the hand 20 in the vertical direction Z based on the reaction force Rz acting in the upward direction Z1 in the vertical direction Z on the hand 20 from the article 60 via the sheet 70.

[0088] Therefore, even if the shape and size of the article 60 inside the container 50 change from time to time, the hand 20 can press the sheet 70 against the article 60 inside the container 50 with an appropriate force.

[0089] According to the sheet pressing system 1 of this embodiment, the task of pressing down the article 60 contained in the box 50 with the sheet 70 can be automated.

[0090] When the reaction force Rz in the upward direction Z1 in the vertical direction Z that the hand 20 receives from the article 60 via the sheet 70 becomes equal to or greater than a first predetermined value A1, the controller 40 stops or decelerates the movement of the hand 20 in the downward direction Z2 in the vertical direction Z. This makes it possible to prevent the hand 20 from pressing the sheet 70 against the article 60 with too much force, which is advantageous in preventing damage to the article 60.

[0091] The hand 20 is rotatable around an axis θh in the horizontal direction H in accordance with a reaction moment Mθh around an axis θh in the horizontal direction H that the hand 20 receives from the article 60 via the sheet 70. This allows the sheet 70 to follow the shape of the article 60, which is advantageous in reducing the gap C between the article 60 and the sheet 70.

[0092] The sensor 30 detects a reaction moment Mθh of θh around an axis in the horizontal direction H that the hand 20 receives from the article 60 via the sheet 70. This is advantageous in controlling the rotation of the hand 20 based on the reaction moment Mθh of θh around the axis in the horizontal direction H.

[0093] When the reaction moment Mθh about the axis θh in the horizontal direction H that the hand 20 receives from the article 60 via the sheet 70 becomes equal to or less than the second predetermined value A2, the controller 40 stops the rotation of the hand 20 about the axis θh in the horizontal direction H. This is advantageous in preventing the hand 20 from rotating too much about the axis θh in the horizontal direction H, which would cause the sheet 70 to be pushed excessively into the article 60.

[0094] The multi-axis robot arm 10 allows the hand 20 to be suitably moved in the vertical direction Z, and also to be suitably rotated about an axis θh in the horizontal direction H.

[0095] Since the hand 20 holds the upper surface 71 a of the sheet 70 , this is advantageous in preventing the hand 20 from coming into contact with the inner wall 52 of the box 50 , compared to when the hand 20 holds the peripheral edge of the sheet 70 .

[0096] Since the suction pad 23 of the hand 20 suctions the upper surface 71a of the sheet 70 by negative pressure, the hand 20 can easily hold the sheet 70.

[0097] The article 60 includes a medicine 61. The medicine 61 is easily broken if pressed with too much force. The sheet pressing system 1 according to the present embodiment is advantageous in preventing the medicine 61 from being broken. In addition, the system is particularly effective in the field of home medical care, where the medicine 61 is delivered to a home.

[0098] Since the upper end 51 of the box 50 on the upper side Z1 is open and the sheet 70 covers the item 60 from the upper side Z1 inside the box 50, handling is easier than when the end of the box 50 in the horizontal direction H is open and the sheet 70 covers the item 60 from the horizontal direction H inside the box 50.

[0099] Suppose that the pressing device presses the sheet 70 against the article 60 up to a preset pressure. In this case, if the shape or size of the article 60 changes from time to time, the sheet 70 may be pressed against the article 60 with too much force, or conversely, the pressing force of the sheet 70 against the article 60 may not be enough.

[0100] As described above, in the sheet pressing system 1 according to this embodiment, the movement of the hand 20 in the vertical direction Z is controlled based on the reaction force Rz in the upward direction Z1 that the hand 20 receives from the article 60 via the sheet 70, so that the sheet 70 can be pressed with an appropriate force against the article 60. Therefore, the sheet pressing system 1 according to this embodiment is advantageous over the pressing device described above.

[0101] <Second embodiment> A sheet pressing system 1 according to the second embodiment will be described. In the following description, the same components as those in the above embodiment will be denoted by the same reference numerals, and detailed description thereof may be omitted. Figure 7 shows the control of the hand 20 in the second embodiment.

[0102] The controller 40 is switchable between a first control mode T1 and a second control mode T2. In the first control mode T1, the controller 40 moves the hand 20 downward Z2 in the vertical direction Z, not based on a reaction force Rz in the upward direction Z1 of the vertical direction Z. In the second control mode T2, the controller 40 moves the hand 20 downward Z2 in the vertical direction Z based on a reaction force Rz in the upward direction Z1 of the vertical direction Z.

[0103] The speed Vc of the hand 20 moving downward Z2 in the first control mode T1 is greater than the speed Vd of the hand 20 moving downward Z2 in the second control mode T2 (Vc>Vd).

[0104] Before the hand 20 reaches a predetermined position P in the vertical direction Z, the controller 40 moves the hand 20 downward Z2 in the vertical direction Z in the first control mode T1, not based on a reaction force Rz toward the upward direction Z1 in the vertical direction Z.

[0105] After the hand 20 reaches a predetermined position P in the vertical direction Z, the controller 40 moves the hand 20 downward Z2 in the vertical direction Z based on a reaction force Rz toward the upward direction Z1 in the vertical direction Z in the second control mode T2.

[0106] In the first control mode T1, for example, the sensor 30 does not detect the reaction force Rz, or even if the sensor 30 detects the reaction force Rz, the reaction force Rz is not input to the controller 40, or the controller 40 does not compare the reaction force Rz with the first predetermined value A1.

[0107] The other configurations are similar to those of the first embodiment.

[0108] According to this embodiment, the first control mode T1 allows the hand 20 to be quickly moved downward Z2 in the vertical direction Z without being based on the reaction force Rz toward the upward direction Z1 in the vertical direction Z, and the second control mode T2 allows the hand 20 to be carefully moved downward Z2 in the vertical direction Z based on the reaction force Rz toward the upward direction Z1 in the vertical direction Z.

[0109] In the second control mode T2 after the hand 20 has reached the predetermined position P, the hand 20 must be moved based on the reaction force Rz, and therefore the hand 20 can only be moved at a low speed. On the other hand, in the first control mode T1 before the hand 20 has reached the predetermined position P, the hand 20 can be moved without being based on the reaction force Rz, and therefore the hand 20 can be moved at high speed. By quickly moving the hand 20 in the first control mode T1 and then switching to the second control mode T2, the movement time of the hand 20 can be shortened overall.

[0110] <Third embodiment> A sheet pressing system 1 according to the third embodiment will be described. In the following description, the same components as those in the above embodiment will be denoted by the same reference numerals, and detailed description thereof may be omitted. FIG. 8 shows a printed matter feed mechanism 80 according to the third embodiment.

[0111] The sheet holding system 1 includes a printed material insertion mechanism 80. After the sheet 70 is held against the article 60 by the hand 20 inside the box 50, the printed material insertion mechanism 80 inserts a printed material 81 into the box 50 from above Z1 in the vertical direction Z relative to the sheet 70 inside the box 50.

[0112] The printed matter 81 is paper. The printed matter 81 shows information 82 about the item 60. For example, the printed matter 81 shows information 82 about the medicine 61 (such as type, usage, and quantity). The printed matter 81 may also show information 82 (such as a delivery slip) for the customer (user) who will receive the item 60. The printed matter 81 may be folded in half, for example.

[0113] The other configurations are similar to those of the first and second embodiments.

[0114] According to this embodiment, the printed matter 81 is less likely to be lost, compared to when a cushioning material is filled in the gap between the box 50 and the article 60.

[0115] <Other embodiments> Although the present disclosure has been described above with reference to the preferred embodiments, such description is not limiting, and it goes without saying that various modifications, substitutions, or combinations are possible.

[0116] In the hand 20, the suction pads 23 may be provided in the center of the lower surface of the frame 21, rather than at the four corners. That is, the suction pads 23 may suction and hold the center of the upper surface 71a of the sheet 70, rather than at the four corners. The frame 21 does not have to be rectangular, and may be, for example, circular. The number of suction pads 23 does not have to be four, and may be, for example, one to three, or five or more.

[0117] In the above embodiment, the hand 20 suction-holds the upper surface 71a of the sheet 70 by using the suction pad 23, but this is not limited thereto. For example, the hand 20 may adhesively hold the sheet 70 by using an adhesive material or the like. The hand 20 may grip the holes 74 provided in the sheet 70. The hand 20 may grip the periphery of the sheet 70.

[0118] The multi-axis robot arm 10 may be omitted.

[0119] The sensor 30 does not need to detect the reaction moment Mθh about the axis θh in the horizontal direction H that the hand 20 receives from the article 60 via the sheet 70. The hand 20 does not need to be able to rotate about the axis θh in the horizontal direction H. Conversely, the hand 20 may be actively rotated about the axis θh in the horizontal direction H by the multi-axis robot arm 10.

[0120] In the horizontal direction H, X may be the left-right direction and Y may be the front-back direction.

[0121] The first direction may be the horizontal direction H, and the second direction may be the up-down direction Z. In this case, the end of the box 50 in the horizontal direction H is open, and the sheet 70 covers the article 60 inside the box 50 from the horizontal direction H.

[0122] The hand 20 is required to be able to move at least in the first direction, and the sensor 30 is required to be able to detect a reaction force in at least one direction of the first direction Z.

[0123] The box 50 and the sheet 70 may be circular.

[0124] The article 60 may not include the drug 61 . [Industrial Applicability]

[0125] The present disclosure is applicable to sheet holding down systems and is therefore extremely useful and has high industrial applicability. [Explanation of symbols]

[0126] Z Vertical direction (first direction) Z1 Upper (one side) Z2 Downward (other side) H Horizontal direction (second direction) X Anteroposterior direction Y left / right direction θh axis rotation Rz reaction force Mθh Reaction moment A1 First predetermined value A2 Second predetermined value A3 Third specified value Va speed Vb speed Vc speed Vd speed C Gap T1 First control mode T2 Second control mode P Predetermined position 1 Sheet holding system 10 Multi-axis robot arm 20 Hands 21 Frame 22 Connectors 23 Suction pad 30 Sensors 40 Controller 50 box body 51 Upper end 51a opening 52 Inner wall 60 Goods 60a Upper end 61 Drugs 62 Medicine Bag 70 sheets 71 Main body 71a Top side 72 Locking piece 72a Flap 73 Fold line 74 holes 80 Print material input mechanism 81 Printed matter 82 Information

Claims

1. a hand that holds a sheet covering an object housed in a box having an open end in a first direction from one side in the first direction and that moves the sheet in the other side in the first direction to press the sheet against the object; a sensor that detects a reaction force in one of the first directions that the hand receives from the object via the sheet; a controller that controls the movement of the hand in the first direction based on the reaction force.

2. The sheet pressing system according to claim 1 , wherein the controller stops or decelerates the movement of the hand in the other of the first directions when the reaction force becomes equal to or greater than a first predetermined value.

3. The sheet pressing system according to claim 1 or 2, wherein the hand is rotatable about an axis in the second direction in accordance with a reaction moment about an axis in the second direction intersecting the first direction that the hand receives from the article via the sheet.

4. The sheet hold-down system of claim 3 , wherein the sensor detects the reaction moment.

5. The sheet pressing system according to claim 4 , wherein the controller stops the rotation of the hand about the axis in the second direction when the reaction moment becomes equal to or less than a second predetermined value.

6. A multi-axis robot arm for moving the hand is provided, The sheet pressing system according to claim 3 , wherein the multi-axis robot arm moves the hand in the first direction and rotates the hand about an axis in the second direction.

7. The sheet pressing system according to claim 1 , wherein the hand holds a surface of the sheet facing one side in the first direction.

8. The sheet pressing system according to claim 7 , wherein the hand attracts a surface of the sheet facing one side in the first direction by negative pressure.

9. 3. The sheet holding system according to claim 1, wherein the controller is switchable between a first control mode in which the hand is moved in the other direction of the first direction without being based on the reaction force, and a second control mode in which the hand is moved in the other direction of the first direction based on the reaction force.

10. 10. The sheet holding system of claim 9, wherein the controller uses the first control mode to move the hand in the other direction of the first direction without using the reaction force before the hand reaches a predetermined position in the first direction, and uses the second control mode to move the hand in the other direction of the first direction based on the reaction force after the hand reaches the predetermined position.

11. The sheet holding system of claim 1 or 2, further comprising a printed material insertion mechanism that inserts a printed material indicating information about the item from one of the first directions relative to the sheet after the sheet is pressed against the item by the hand.

12. The sheet retention system of claim 1 or 2, wherein the article includes a medicine.

13. The first direction is an up-down direction, One of the first directions is upward, The sheet holding down system according to claim 1 or 2, wherein the other of the first directions is a downward direction.

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