Method for opening a box and facility for implementing the opening method

Abstract

The invention relates to a method for opening a box, wherein: a box is placed at the input (12a) of a main conveyor (12), the box (100) is transferred to the cutting station (30) by means of the main conveyor (12); a cut is made in the upper wall (102) of the box (100) along a cutting path by means of the cutting device (34), the cutting path (C) forming an open continuous loop comprising a continuous cutting line and at least one first uncut zone (x1) so as to obtain a cut-out wall part (110) which is connected to the body of the box (100) by at least a first connecting portion (112, 114); then the cut-out box is transferred to the discharge station (40) (12); then the cut-out wall part (110) is grasped by means of the gripping device (44) and the cut-out wall part (110) is detached from the body (101) of the box (100) by breaking the first connecting portion; then the cut-out wall part (110) is discharged by means of the gripping device (44).

Description

[0001] Title of the invention: Method for opening a box and installation for implementing said opening method.

[0002] Technical field

[0003] This presentation relates to the field of box opening, in particular cardboard packaging boxes. In particular, it relates to a method for the automated opening of boxes and the corresponding installation found, for example, in logistics centers or warehouses.

[0004] Prior art

[0005] In the past, boxes were opened manually to extract the items and products being transported. Since this manual work was time-consuming, sometimes dangerous, and likely to damage the products inside the boxes, logistics centers have gradually been equipped with automated systems to automatically open boxes.

[0006] These installations implement opening processes in which a cutting tool, generally comprising a blade, makes continuous cuts or pre-cuts in the box.

[0007] Document EP 2 894 017 describes a can opening installation in which the can to be opened is first tilted. Then a suction cup holds one wall of the can while a blade mounted on an articulated arm makes a cut around the suction cup. After cutting the wall of the can, the suction cup is moved so as to open the wall of the can.

[0008] In this installation, the box face is cut and the opening is performed simultaneously. Although this type of arrangement may have an advantage in terms of space requirements, it nevertheless has several disadvantages. In particular, maintenance operations are complex and time-consuming due to the accumulation of actuators and tools in a small volume.

[0009] In addition, this installation requires tilting the box before cutting, which could create a risk of breakage, for example if the box contains fragile products.

[0010] Statement of the invention

[0011] One aim of the presentation is to propose a method for opening a box which overcomes the aforementioned drawbacks and offers greater ease of maintenance.

[0012] The aim is achieved by a method for opening a box, in which: an installation is provided comprising a main conveyor extending in a longitudinal direction and having a direction of advance and, considered according to the direction of advance, the installation successively comprises: a cutting station comprising a cutting robot equipped with a cutting device having a blade, and a discharge station, located downstream of the cutting device, the discharge station comprising a gripping robot equipped with a gripping device; the opening method comprising the following steps: a box is placed at the inlet of the main conveyor, the box having a body closed by an upper wall; the box is brought into the cutting station using the main conveyor;a cut is made in the upper wall of the box along a cutting path using the cutting device, said cutting path forming an open continuous loop which comprises at least a first continuous cutting line and at least a first uncut zone so as to obtain a cut wall part which is connected to the body of the box by at least a first connecting portion; then the cut box is brought into the discharge station using the main conveyor; then the cut wall part is grasped using the gripping device and the gripping device is moved in order to detach the cut wall part from the body of the box by breaking the first connecting portion;then the cut wall portion is evacuated using the gripping device. It is understood that the cutting and evacuation steps are carried out sequentially in two different stations which are distant from each other in the longitudinal direction, the two stations being arranged one downstream of the other according to the direction of advance of the boxes on the main conveyor. The cut wall portion is held to the rest of the box by the first connecting portion during the transfer to the evacuation station.;

[0013] The cutting robot and the gripping robot comprise multi-axis robotic arms, known elsewhere, which are controlled by a control device.

[0014] For the purposes of the disclosure, the top wall is the upper wall of the box which is generally horizontal.

[0015] The main conveyor is preferably a roller conveyor. It could also be a belt conveyor, as these types of conveyors are known elsewhere.

[0016] It is also understood that the main conveyor includes a moving device for moving the boxes in the direction of travel.

[0017] According to the description, the box is preferably made of cardboard, or any other material of the same type. It has the general shape of a parallelepiped.

[0018] The cutting path is preferably recorded in a memory, for example a memory of a PLC or the cutting robot control device.

[0019] Without departing from the scope of the present invention, the cutting device may comprise several blades.

[0020] It is further understood that the first connecting portion is made up of the material of the first uncut area of ​​the upper wall which is not cut. This first connecting portion constitutes a first breakable fastener which holds the cut wall portion to the rest of the box during its transfer to the evacuation station.

[0021] Preferably, the cutting path has a generally rectangular shape whose edges are substantially parallel to the edges of the upper wall of the box. It is understood that the gripping device grasps and then pulls on the cut wall portion in order to tear the fastener, or fasteners, constituted by the first uncut area, and where appropriate by the second uncut area.

[0022] The gripping device preferably comprises suction cups connected to a suction device. The suction cups define a suction zone whose surface can be modified depending on the size of the part of the cut wall to be gripped and evacuated.

[0023] The dimensions of the uncut areas will be chosen to ensure easy detachment of the cut-out wall section.

[0024] In some embodiments, the length of the first uncut area is at most equal to 10% of the length of the first continuous cutting line. More preferably, the length of the first uncut area is at most equal to 5% of the length of the first continuous cutting line. More preferably, the length of the first uncut area represents less than 10% of the length of the cutting path. It is understood that the length of the cutting path is equal to the sum of the length of the first continuous cutting line and the length of the first uncut area when the open loop comprises a single first uncut area. Preferably, the length of the first continuous cutting line represents at least 95% of the length of the cutting path.

[0025] In some embodiments, the cutting is performed such that the open continuous loop further comprises a second continuous cutting line and a second uncut area, such that the cut wall portion is connected to the body of the box by the first connecting portion and by a second connecting portion, the first and second continuous cutting lines being separated from each other by the first and second connecting portions.

[0026] We understand that the continuous loop is open in two zones which correspond to the first and second uncut zones.

[0027] The cutting path, forming the open continuous loop, is therefore in this variant made up of the first and second continuous cutting lines, and the first and second uncut areas. The length of the second uncut area is at most equal to 10% of the length of the second continuous cutting line. More preferably, the length of the second uncut area is at most equal to 5% of the length of the second continuous cutting line.

[0028] In this embodiment, the length of the cutting path is equal to the sum of the lengths of the first and second continuous cutting lines and the lengths of the first and second uncut areas. The sum of the lengths of the first and second continuous cutting lines represents at least 95% of the length of the cutting path.

[0029] It is understood that the second connecting portion constitutes a second breakable fastener; the first and second breakable fasteners hold the cut wall portion. Thanks to the presence of the second connecting portion, the cut wall portion is better held and remains substantially horizontal before the evacuation step.

[0030] Preferably, the first and second connecting portions are made so as to be positioned at two opposite edges of the cut-out wall portion.

[0031] In certain embodiments, the installation further comprises a measuring station located upstream of the cutting station, the measuring station comprising at least one measuring device, and in which the dimensions of the box are measured using the measuring device, and the cutting path is determined from the dimensions measured by the measuring device.

[0032] The box is preferably measured in three dimensions: its height, length and width. Preferably, the height of the box, and the length and width of the top wall are measured.

[0033] According to a preferred implementation mode, the coordinates of the cutting path are calculated from the dimensions of the box measured by the measuring device.

[0034] Preferably, the coordinates of the cutting path are calculated using a calculator so that the distance between the longitudinal edge and / or the transverse edge of the upper wall to be cut and the cutting path is equal to a predetermined value. This value is previously entered and / or recorded in the calculator. This value can be a constant or a percentage of the measured length of one of the edges of the box. Preferably, the distance between the cutting path and the longitudinal edge is identical to the distance between the cutting path and the transverse edge of the upper wall. Without departing from the scope of the present invention, different distances can be chosen by setting different predetermined values ​​for the longitudinal and transverse edges of the box.

[0035] The measuring device preferably includes a laser profilometer.

[0036] Preferably, the position of the box in a horizontal plane is corrected before the measuring step. One advantage is to improve the accuracy of the measurement but also to correct the position of the box before it is brought into the cutting station.

[0037] The position correction is carried out so that one of the edges of the box is parallel to the direction of travel of the main conveyor.

[0038] In some implementations, the position of the box in a horizontal plane is corrected in the cutting station before the top wall cutting step. This step allows for better positioning of the cut in the top wall and ensures the reproducibility of the cut.

[0039] In certain embodiments, the installation further comprises a secondary conveyor, and the cut wall portion is evacuated onto the secondary conveyor using the gripping device.

[0040] It is understood that the gripping device detaches the cut wall part and then brings it onto the secondary conveyor. The secondary conveyor can, for example, be associated with a receptacle to receive the cut wall parts from the boxes.

[0041] According to a preferred embodiment, between two successive cuts of two boxes, an image of the blade is acquired using an image acquisition device mounted on the cutting device and the wear or breakage of the blade is determined from said image.

[0042] The image acquisition device preferably comprises a camera. The image acquisition device is preferably connected to an analysis device configured to determine the wear or breakage of the blade from the image acquired by the image acquisition device. When the blade has several cutting edges, the image acquisition device can also be configured to acquire an image of the cutting edges and the wear of each of the cutting edges of the blade is determined. The wear or breakage of the blade and / or the cutting edges may be determined by an automated process implementing a comparison step between the image of the blade, or its shadow, and an image of an unworn blade.

[0043] In an exemplary implementation, the blade has a first cutting edge and a second cutting edge opposite the first cutting edge. The cutting is first carried out with the first cutting edge. When the first cutting edge exhibits significant wear, for example exceeding a predetermined threshold such as a consumed blade surface threshold, determined by a computer from the image of the blade, the cutting device is pivoted 180° so as to continue the cutting using the second cutting edge. It is understood that the 180° pivoting of the cutting device makes it possible to bring the second cutting edge into the cutting position.

[0044] In certain embodiments, the installation further comprises a store of replacement blades which is arranged in a drawer adjacent to the cutting robot, and the worn or broken blade is replaced with a replacement blade in the event of breakage or if the determined wear is greater than a predetermined threshold.

[0045] The blade magazine holds several replacement blades. It also holds used blades.

[0046] The drawer is arranged so that only the cutting robot can access the spare blade magazine when the drawer is closed, while only the operator can access the magazine when the drawer is open, for example to insert new blades and remove worn blades. This advantageous arrangement improves operator safety.

[0047] In some embodiments, the cutting device has two cutting depths, and a thickness datum that is representative of the thickness of the upper wall is transmitted to the cutting robot, and the cutting depth is selected from the thickness datum.

[0048] The thickness data is preferably but not exclusively transmitted to the cutting robot control device by a control signal from a control unit external to the installation.

[0049] Without departing from the scope of this disclosure, the cutting device could have more cutting depths, in order to accommodate different wall thicknesses.

[0050] The disclosure further relates to an installation for implementing the method according to the disclosure, comprising a main conveyor extending in a longitudinal direction and having a direction of advance and, considered in the direction of advance, the installation successively comprises: a cutting station comprising a cutting robot equipped with a cutting device having a blade, and a discharge station, located downstream of the cutting station, the discharge station comprising a gripping robot equipped with a gripping device.

[0051] In some embodiments, the blade has a triangular shape having a first cutting edge and a second cutting edge opposite the first cutting edge.

[0052] In certain embodiments, the installation according to the disclosure further comprises a measuring station arranged for example in the cutting station, the measuring station comprising a measuring device for measuring the dimensions of the box.

[0053] The measuring device preferably includes a laser profilometer that allows the dimensions of the box to be determined, namely the length, width and height. The profilometer allows the length and width of the top wall of the box to be determined.

[0054] The installation further comprises a calculator for calculating the coordinates of the cutting path. As shown below, the coordinates of the cutting path are a function of the width and length of the upper wall and also of at least one predetermined value for setting the distance between the cutting path and the longitudinal and transverse edges of the upper wall.

[0055] According to certain embodiments, the installation further comprises a secondary conveyor, parallel to the main conveyor, and in which the gripping robot is arranged between the main conveyor and the secondary conveyor. The secondary conveyor preferably comprises an adhesive or non-slip strip, for example made of PVC, making it possible to ensure that the cut wall parts do not fall off the secondary conveyor.

[0056] The secondary conveyor preferably, but not exclusively, has a direction of movement opposite to the direction of advance of the main conveyor.

[0057] The secondary conveyor can be associated with a waste conveyor.

[0058] In some embodiments, the cutting device has two cutting depths.

[0059] The cutting device therefore makes it possible to adapt to the thickness of the upper wall to be cut. Preferably, the cutting device comprises a support member configured to come into contact with the upper face of the box to be cut, the blade being movable relative to the support member so as to modify the cutting depth.

[0060] Preferably, the cutting device includes an image acquisition device for acquiring an image of the blade. More preferably, the installation includes an analysis device for determining the wear of the blade from the image acquired by the image acquisition device. For example, the acquired image is compared to an image of a new blade so as to identify, by comparison, a breakage or a worn part. The comparison may in particular consist of determining, with a calculator, the consumed surface area of ​​the worn blade compared to an image of a new blade. A predetermined wear threshold may be chosen in order to determine from when the blade must be replaced.

[0061] Advantageously, and for safety reasons, the installation according to the disclosure further comprises an enclosure in which the cutting station and the gripping station are arranged, and a store of spare blades arranged in a drawer sliding in an opening made in the enclosure. It is understood that the enclosure is preferably crossed by the main conveyor.

[0062] Preferably, the gripping device comprises suction members. The suction members define a suction surface and are separately operable so as to modulate the suction surface as a function of the surface area of ​​the cut wall portion to be removed.

[0063] Description of the drawings

[0064] The invention will be better understood on reading the following description of an embodiment of the disclosure given as a non-limiting example, with reference to the appended drawings, in which:

[0065] [Fig. 1] Figure 1 is a perspective view of an embodiment of the can opening installation according to the disclosure implementing the method according to the disclosure;

[0066] [Fig. 2] Figure 2 is a detail view of a measuring station of the installation of Figure 1;

[0067] [Fig. 3] Figure 3 is a detail view of the cutting station of the installation of Figure 1;

[0068] [Fig. 4] Figure 4 illustrates in top view and schematically a device for correcting the position of the boxes in the cutting station;

[0069] [Fig. 5] Figure 5 illustrates a top view of the upper face of the box after the cutting operation;

[0070] [Fig. 6] Figure 6 is a detail view of the spare blade magazine;

[0071] [Fig. 7] Figure 7 illustrates the transfer of the cut box between the cutting station and the discharge station;

[0072] [Fig. 8] Figure 8 is a detail view of the evacuation station;

[0073] [Fig. 9] Figure 9 illustrates in top view and schematically the box cut on the main conveyor and the portion of wall which has been evacuated on the secondary conveyor; and

[0074] [Fig. 10] Figure 10 is a detail view of the slide image acquisition device.

[0075] Detailed description

[0076] With the aid of figures 1 to 10, an installation 10 for opening boxes, in particular cardboard boxes containing articles, and the method of opening a box which is implemented by this installation will be described. In this example, the boxes are cardboard boxes, having a generally parallelepiped shape, known elsewhere and which are traditionally used for transporting articles. The installation 10 has the function of automatically opening such boxes, and more precisely an upper face 102 of the box. The installation 10 receives at the input a box 100 provides at the output a box whose upper face 102 has an opening 104.

[0077] The installation 10 comprises a main conveyor 12, in this example a roller conveyor 14, which extends in a longitudinal direction D and which has a direction of advance S between an upstream part 12a and a downstream part 12b of the main conveyor 12.

[0078] In several of the figures, an XYZ coordinate system is shown. The longitudinal direction D is parallel to the X axis, the width of the main conveyor extends along the Y axis and the Z axis is vertical.

[0079] The rollers 14 of the main conveyor 12 are driven in rotation by drive means, known elsewhere and not illustrated here.

[0080] In the following description, the terms upstream and downstream will be considered with reference to the direction of advance S.

[0081] Considered in the direction of advance S, from upstream to downstream, the installation 10 according to the exemplary embodiment comprises successively: a measuring station 20, a cutting station 30 and an evacuation station 40. It is understood that the box is initially deposited in the upstream part 12a of the main conveyor 12, that is to say upstream of the measuring station 20. The open box leaves via the downstream part 12a of the evacuation station 40.

[0082] It is further understood that the measuring station 20 is arranged upstream of the cutting station 30, while the evacuation station 40 is located downstream of the cutting device 30. Referring to FIG. 1, it is understood that the evacuation station is arranged at a distance from the cutting station, considered in the direction of advance S.

[0083] The installation 10 comprises, in this exemplary embodiment, at least one device 50 for correcting the position of the box on the main conveyor 12. Such a position correction device 50 can be placed at several locations on the main conveyor, for example in the cutting station and / or in the discharge station.

[0084] With the aid of FIG. 2, the measuring station 20 will be described. This measuring station 20 comprises a measuring device 22 for measuring the dimensions of the box 100, namely the length and width of the upper wall, and the height of the box.

[0085] To do this, in this example, the measuring device 22 comprises a laser profilometer 24 mounted at the upper end of an arm 26. The laser beam is shown diagrammatically by the line 28 while the grayed-out surface 29 illustrates the surface scanned by the laser beam.

[0086] The measuring device 22 is connected to a controller of the installation.

[0087] Arranged downstream of the measuring station, the cutting station 30 comprises a cutting robot 32 equipped with a cutting device 34 comprising a blade 35. In this example, the blade 35 has a triangular shape and comprises a first cutting edge and a second cutting edge opposite the first cutting edge.

[0088] The cutting robot 32 is in this example a multi-axis Fanuc brand robot, which makes it possible to move the cutting device 34 in space in the X, Y and Z directions. The cutting device 34 has in this example two cutting depths, in order to adapt to the thickness of the upper wall 102. It is specified that, in this example, the information relating to the thickness of the upper wall is provided to the control device of the installation, for example via an external signal.

[0089] According to the method described, the box is brought into the cutting station 30 using the main conveyor 12. In this example, the position of the box 100 is first corrected using a position correction device 50 illustrated in FIG. 4.

[0090] The position correction device 50 comprises a first retractable stop 52 which extends along the width of the main conveyor 12, oriented along the Y axis. This first stop 52 has the function of stopping the movement of the box 100 in the direction of advance S. The position correction device further comprises an actuator 54 provided with a plate 56 which is movable along the Y axis so as to push the box 100 against an edge 13 of the main conveyor 12 and which extends parallel to the longitudinal direction of the conveyor. It is understood that the position correction device makes it possible to align one of the side walls 104 of the box parallel to the X axis, and a second side wall, perpendicular to the first side wall 104 parallel to the Y axis.

[0091] After correction of the position, a cut is made in the upper wall 102 of the box 100 along a cutting path B using the cutting device 34. Referring to FIG. 5, it can be seen that the cutting path B forms an open continuous loop comprising a first continuous cutting line LC1 and a second continuous cutting line LC2. The open continuous loop also comprises a first uncut zone Z1 and a second uncut zone Z2, the first and second uncut zones Z1, Z2 separating the first and second continuous lines LC1, LC2.

[0092] With the aid of Figure 5, it is understood that the cutting path B delimits a cut wall portion 104 from the rest of the body 101 of the box 100. More precisely, the cut wall portion 104 remains connected to the body 101 of the box 100 by a first connecting portion 106 formed by the first uncut zone Z1, and by a second connecting portion 108 which is formed by the second uncut zone Z2. The first and second connecting portions constitute breakable fasteners which have the function of keeping the cut wall portion integral with the rest of the box during the transfer from the cutting station to the evacuation station.

[0093] It should be noted that the thickness of the cutting path B illustrated in figure 5 is deliberately exaggerated in order to facilitate understanding.

[0094] In this example, the cutting path B has a generally rectangular shape whose longitudinal and transverse edges are substantially parallel to the side walls 104 and 106 of the box. The cutting path B has a length U and a width V.

[0095] The cutting path B forms an open loop which, in this example, consists of two continuous cutting lines, namely a first continuous cutting line LC1 and a second continuous cutting line portion LC2 which are separated from each other by the first and second connecting portions 112, 114. In the example of FIG. 5, the first and second connecting portions 112, 114 are located in the transverse edges of the cutting path. Without departing from the scope of the present invention, the first and second connecting portions could be produced in other locations, provided that they make it possible to keep the cut wall portion 110 sufficiently horizontal to facilitate the subsequent evacuation operation.

[0096] Furthermore, the sum of the lengths of the first and second continuous cutting lines LC1, LC2, namely 2*(U+V)-dl-d2, represents at least 90% of the length of the length of the cutting path B, namely 2*(U+V).

[0097] The length dl of the first uncut area ZI is, in this example, less than 10% of the length of the first continuous cutting line LC1. In addition, the sum of the lengths dl,d2 of the first and second uncut areas Z1,Z2 is less than 10% of the sum of the lengths of the first and second continuous cutting lines LC1, LC2.

[0098] It can also be seen that the cut-out wall portion 110 has two longitudinal edges 120a, 120b, and two transverse edges 120c, 120d.

[0099] It can be seen that the longitudinal edge 120a of the cutting path is arranged at a distance a from the longitudinal edge 104 of the upper wall, while the transverse edge 120c of the cutting path is located at the distance b from the transverse edge 106 of the upper wall. The distances a and b are set in the control device of the cutting device. It can be a constant value, for example of the order of a few centimeters, or a value which is calculated from the length L or the width f of the box measured by the measuring station.

[0100] It is specified that the method according to the invention makes it possible to make openings in the upper wall of boxes without knowing a priori the dimensions of the box to be cut, insofar as the cutting path is determined from the dimensions measured by the measuring device. In other words, the box opening method adapts to the dimensions of the box entering the installation.

[0101] After the cutting operation, the stop 52 is retracted after which the box 100 continues its movement on the main conveyor 12 in the direction of advance S towards the evacuation station 40 which is located downstream of the cutting device, as shown diagrammatically in FIG. 7.

[0102] Referring to Figure 8, the discharge station 40 will be described in more detail.

[0103] The discharge station 40 comprises a gripping robot 42, in this example similar to the cutting robot, the gripping robot 42 being provided with a gripping device 44.

[0104] The gripping device 44 comprises suction members 46 in the form of suction cups which are carried by a frame 48. The frame 48 carries several suction members 46 so as to be able to grip parts of cut walls having different sizes.

[0105] According to the invention, the cut-out wall portion 110 is grasped using the gripping device 44, by actuating the suction members, and the gripping device is moved in order to detach the cut-out wall portion from the body 101 of the box 100 by breaking or tearing the first and second breakable fasteners constituted by the first and second connecting portions 112, 114.

[0106] To do this, after gripping the cut wall portion 110, the gripping device 44 is moved upwards so as to tear the first and second connecting portions, after which the cut wall portion 110 is separated from the rest of the box. Then, the cut wall portion 110 is evacuated using the gripping device 44 onto a secondary conveyor 60 using the gripping device 44.

[0107] In this example, the secondary conveyor 60, illustrated in FIG. 9, extends parallel to the longitudinal direction D of the main conveyor 12. It has a direction of advance S' which is opposite to the direction of advance S of the main conveyor 12. The secondary conveyor is a belt conveyor which in this example comprises an adhesive strip, for example made of PVC, so as to prevent the cut wall parts from falling from the secondary conveyor.

[0108] The secondary conveyor 60 can also be associated with a waste conveyor, arranged downstream of the secondary conveyor S'.

[0109] Furthermore, the gripping robot 42 is arranged between the main conveyor 12 and the secondary conveyor 60, which makes it easier to remove the cut wall portion while limiting the transverse size of the installation.

[0110] According to the disclosure, the installation further includes an image acquisition device 39 for acquiring an image of the blade 35.

[0111] This image acquisition device 39 is, in this example of FIG. 10, arranged in the cutting station and associated with a backlighting device 41. The cutting device is brought between the image acquisition device 39 and the backlighting device 41 during the acquisition of the image of the slide.

[0112] The images taken by the image acquisition device 39 are transmitted to a breakage or wear detection device comprising a computer which compares the image of the blade 35, or its shadow, with a profile of a new blade so as to determine, by comparison of shapes, the state of wear or breakage of the blade. The acquisition of the image of the blade and the analysis of the level of wear or the detection of breakage is preferably but not necessarily carried out between two successive cuts of two boxes.

[0113] The comparative analysis therefore makes it possible to determine the level of wear of the blade 35 or its breakage.

[0114] The blade will be replaced if its wear level exceeds a predetermined threshold. The wear level can, for example, be a wear rate corresponding to a ratio between the shape of the worn blade, determined by imaging, and the shape of a new blade.

[0115] The installation 10 further comprises an enclosure 70 in which are arranged at least the cutting station 30 and the evacuation station 40 and a spare blade magazine 72 which is housed in a drawer mounted to slide in an opening 76 provided in the enclosure 70.

[0116] The magazine 72 includes replacement blades 78 as well as locations for receiving worn blades. When the drawer is open, as illustrated in FIG. 6, the operator can place replacement blades 78 in the drawer and remove worn blades replaced by the cutting robot.

[0117] When the drawer is closed, the spare blade magazine is located inside the enclosure and the cutting device can remove a used blade and pick up a new blade. To do this, the cutting device has a controllable jaw for picking up the blades.

[0118] Preferably, the detection of blade wear or breakage is carried out while the cutting device 34 is located above the spare blade magazine 72. One advantage is to be able to quickly change the blade if the breakage or wear detection device detects significant breakage or wear requiring the blade to be replaced with a new blade.

[0119] As illustrated in Figure 10, the installation also includes a blade presence sensor 37, mounted on the cutting head, the function of which is to ensure the presence of a replacement blade in the replacement blade magazine.

[0120] The detection of the presence of a new blade in the magazine is carried out by the blade presence sensor 37 when the cutting device 34 is located above the spare blade magazine 72.

Claims

DEMANDS 1. A method for opening a box, in which: an installation (10) is provided comprising a main conveyor extending in a longitudinal direction and having a direction of travel, and, considered in the direction of travel, the installation comprises successively: a cutting station (30) comprising a cutting robot (32) equipped with a cutting device (34) having a blade (35), and an evacuation station (40), located downstream of the cutting station, the evacuation station (40) comprising a gripping robot (42) equipped with a gripping device (44); the opening method comprising the following steps: a box is placed at the inlet (12a) of the main conveyor (12), the box having a body provided with an upper wall (102); the box (100) is brought into the cutting station (30) by means of the main conveyor (12);a cut is made in the upper wall (102) of the box (100) along a cutting path using the cutting device (34), said cutting path (C) forming a continuous open loop comprising at least a first continuous cutting line (LC1) and at least a first uncut zone (xl) so as to obtain a cut wall portion (110) which is connected to the body of the box (100) by at least a first connecting portion (112); then the cut box is brought to the discharge station (40) using the main conveyor (12); then the cut wall portion (110) is grasped using the gripping device (44) and the gripping device is moved in order to detach the cut wall portion (110) from the body (101) of the box (100) by breaking the first connecting portion; then the cut-out section of wall (110) is removed using the gripping device (44).

2. Method according to claim 1, wherein the length of the first uncut zone is at most equal to 10% of the length of said first continuous cutting line (LC1).

3. Method according to claim 1 or 2, wherein the cutting is carried out so that the continuous open loop further comprises a second continuous cutting line (LC2) and a second uncut zone (Z2), such that the cut wall portion is connected to the body of the box by the first connecting portion (112) and by a second connecting portion (114), the first and second continuous cutting lines (LC1,LC2) being separated from each other by the first and second connecting portions (112,114).

4. A method according to any one of claims 1 to 3, wherein the installation further comprises a measuring station located upstream of the cutting station, the measuring station (20) comprising at least one measuring device (22), and wherein the dimensions (L, W, H) of the box are measured using the measuring device, and the cutting path (C) is determined from the dimensions measured by the measuring device.

5. A method according to any one of the preceding claims, wherein the position of the box (100) is corrected in a horizontal plane (P) before the cutting step of the upper wall.

6. A method according to any one of the preceding claims, wherein the installation further comprises a secondary conveyor, and wherein the cut wall portion (110) is evacuated onto the secondary conveyor (60) using the gripping device.

7. A method according to any one of the preceding claims, wherein, between two successive cuts of two boxes, an image of the blade is acquired using an image acquisition device (37) mounted on the cutting device (34) and the wear or breakage of the blade (35) is determined from said image.

8. A method according to claim 7, wherein the installation further comprises a spare blade magazine disposed in a drawer adjacent to the cutting robot, and the worn blade or broken by a replacement blade in case of breakage or if the determined wear is greater than a predetermined threshold.

9. A method according to any one of the preceding claims, wherein the cutting device has two cutting depths, wherein a thickness data is transmitted to the cutting robot which is representative of the thickness of the upper wall, and the cutting depth is selected from the thickness data.

10. Installation (10) for implementing the process according to any one of the preceding claims, comprising a main conveyor (12) extending in a longitudinal direction (D) and having a direction of travel (S) and, considered in the direction of travel, the installation comprises successively: a cutting station (30) comprising a cutting robot (32) equipped with a cutting device (34) having a blade (35), and an evacuation station (40), located downstream of the cutting device (30), the evacuation station comprising a gripper robot equipped with a gripper device.

11. Installation according to claim 10, further comprising a measuring station (20) disposed in the cutting station (30), the measuring station comprising a measuring device (22) for measuring the dimensions (L, W, H) of the box (100).

12. Installation according to claim 10 or 11, further comprising a secondary conveyor (60), parallel to the main conveyor, and in which the gripping robot (42) is arranged between the main conveyor (12) and the secondary conveyor (60).

13. Installation according to any one of claims 10 to 12, wherein the cutting device (34) has two cutting depths.

14. Installation according to any one of claims 10 to 13, wherein the cutting device (34) includes an image acquisition device (37) for acquiring an image of the blade (35).

15. Installation according to any one of claims 10 to 14, further comprising an enclosure in which are arranged the cutting station (30) and the evacuation station (40), and a spare blade magazine (72) arranged in a drawer which is mounted to slide in an opening provided in the enclosure.

16. Installation according to any one of claims 10 to 15, in which the gripping device (44) includes suction members (46).

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