GRIPPING TOOL FOR WIRE MESH CONTAINERS AND TRANSFER SYSTEM INCLUDING IT

Abstract

GRIPPING TOOL FOR WIRE MESH CONTAINERS AND TRANSFER SYSTEM COMPRISING THEREOF The invention relates to a gripping tool (1) for wire mesh containers comprising a frame (2) which carries a support assembly (3) defining a support plane and configured to be able to come into contact with an underside of a bottom wire mesh of the container, characterized in that the gripping tool (1) further comprises a clamping assembly (4) carried by the frame (2) and comprising at least one pair (7G, 7D) of gripper members (70, 71) and an actuation mechanism (8) able to move the gripper members (70, 71) relative to each other so as to move, in use, the clamping assembly (4) between an inactive unlocked position in which the gripper members (70, 71) are separated from each other so as to allow movement of a container relative to the support assembly (3) on which it rests,and an active locking position in which the gripper-forming elements (70, 71) are capable of gripping a wire or similar element of the bottom grid so as to hold the container in position on the support assembly (3). The present invention also relates to a transfer system comprising a robotic arm carrying such a gripping tool (1). Figure to be published with the abbreviation: Figure 2.

Description

Title of the invention: GRIPPING TOOL FOR WIRE MESH CONTAINER AND TRANSFER SYSTEM INCLUDING THEM

[0001] The present invention relates to the field of gripping containers for the purpose of transferring them, in particular, gripping wire mesh containers for the purpose of unloading and loading them.

[0002] The present invention relates to a gripping tool for a wire mesh container and a transfer system comprising it.

[0003] A wire mesh container is defined as any container or receptacle having at least one bottom wall made of wire or largely perforated, in other words, a bottom through which a plurality of openings or meshes pass, regardless of the material of said container. For example, such a container may be a metal tray having a bottom wall made of wire and a lateral peripheral wall made of wire.

[0004] The gripping tool and transfer system according to the present invention are particularly, but not exclusively, suited for use in the poultry industry, and more specifically, for handling an egg tray. Such an egg tray, constructed of wire mesh, generally comprises a wire mesh base on which the small end of each egg rests and a wire mesh support positioned above and connected to the base. The base and the support are made of transverse and longitudinal wires. The mesh of the support has larger openings than the mesh of the base, thus allowing the eggs to pass only through the openings of the wire mesh support, and between which the eggs can be placed individually. The gripping tool according to the present invention could, however, be used with other configurations of egg trays, and more generally with wire mesh containers.A plurality of egg trays are stored one above the other in a sliding trolley, each tray resting on the trolley's slides.

[0005] Another area of ​​application for the present invention is, among others, the field of baking. Indeed, during their production, bakery, pastry, or viennoiserie products are often supported on a wire mesh support tray. Such a tray generally consists of a grid formed by a plurality of parallel metal wires. Similar to egg trays, a plurality of support trays are stored one above the other in a sliding trolley, each tray resting on the trolley's slides.

[0006] It is emphasized that the application of the present invention is not limited to a particular type of content. In other words, the wire mesh container intended to be handled by the gripping tool and the transfer system according to the present invention could contain both fragile items, such as eggs, and any other item, whether or not it is entirely contained within the volume of the container.

[0007] Currently, the handling of such containers, particularly between a container storage area and a machine, is often done manually. An operator manually picks up each container and places them at a workstation or on a dedicated conveyor that moves the containers to the workstation.

[0008] However, such handling requires manpower and results in wasted time. Furthermore, if each container is placed directly by an operator at the workstation, this handling carries a risk of containers falling during transport between the storage area and the workstation. If each container is placed on a dedicated conveyor, such an installation requires a significant amount of space.

[0009] The handling of such containers can also be automated, using a transfer system employing a robot to load and unload the containers. Such a robot is equipped with a gripper arranged to come into contact with a container, grasp it, then move it to an unloading area and unload it.

[0010] Grippers comprising a set of suction cups are known. However, such grippers are not suitable for wire mesh containers.

[0011] Grippers equipped with a means for grasping a container from below, and therefore suitable for wire mesh containers, are also known. For example, French patent FR2797507 describes a grasping and transport means for a three-axis robot comprising an elongated pallet. In practice, the elongated pallet is simply slid under the container to be grasped and then slightly lifts the container to move it between its storage area and a desired unloading area.

[0012] However, with such a gripper, the container being held on the pallet by its own weight only, there is a significant risk of the container falling during its movement.

[0013] The applicant company therefore sought to propose an automated gripping solution, applicable to a wire mesh container as defined above which can be grasped from below and not grasped by means of suction cups, and which avoids any risk of the container falling during its movement between its storage area and its unloading area, particularly in the event of a sudden stop of the system.

[0014] The present invention relates to a gripping tool intended to be mounted on a robotic arm and arranged for handling a wire mesh container comprising at least one wire mesh base or similar material, the lower face of which is at least partially accessible. The gripping tool comprises a frame which carries, on one side thereof, a support assembly defining a support plane for a container and configured to be able to come into contact with a lower face of a bottom grid and to support a container, characterized in that the gripping tool further comprises a clamping assembly carried by the frame, on the first side thereof, and comprising at least one pair of clamping members and an actuation mechanism capable of moving the clamping members relative to each other so as to move, in use, the clamping assembly between an inactive unlocking position in which the clamping members are separated from each other so as to allow movement of a container relative to the support assembly on which it rests, and an active locking position in which the clamping members are capable of gripping a wire or similar of the bottom grid so as to allow the container to be held in position on the support assembly.

[0015] Thus, a container resting on the support assembly is reliably held in position on the support assembly by simply moving the clamping assembly into the active locking position, in other words, by simply tightening the bottom grid of the container. The clamping assembly according to the present invention therefore prevents a container supported by said support assembly from moving relative to the support assembly, and thus prevents the container from falling from the support assembly.

[0016] It will be easily understood that, in the case where the wire mesh container has a widely perforated bottom, the clamping elements are arranged and configured so as to be able, in the active locking position, to clamp a region of a part delimiting an opening or separating two openings of the bottom of a container resting on the support assembly.

[0017] In a particular embodiment, for each pair of clamping elements, the two elements are mounted to rotate only, relative to the frame, at the level of the support plane, around axes of rotation perpendicular to the support plane, such that they are able to be brought closer together or further apart by the actuation mechanism. In use, bringing the clamping elements closer together brings the clamping assembly into the active locking position in which the clamping elements are able to clamp the wire on the frame side or similar of the bottom grid resting on the support assembly, referred to as the rearmost wire, and the element intended to come into contact against a face directed opposite the frame of the rearmost wire, referred to as the front element.is also mounted movably between a retracted position in which the front element is tucked under the support plane and an extended position in which the front element protrudes beyond the support plane.

[0018] The front element or elements is therefore dimensioned and configured to be able to pass through the bottom grid, in other words to be able to move from its retracted position to its extended position through a mesh or an opening in the bottom grid.

[0019] It will be easily understood that, in the case where the wire mesh container has a widely openwork base, the clamping elements are arranged and configured so as to be able, in the active locking position of the clamping assembly, to clamp an area of ​​the base located between the edge on the chassis side, called the rear edge, and an opening adjacent to this rear edge of the base of a container resting on the support assembly, which area is called the extreme rear area.

[0020] Preferably, for the or each pair of gripper members, the front member comprises at least one ratcheting finger having a front stop face, the or each finger being mounted pivoting about a pivot axis located in the plane of the support assembly and parallel to the plane of the front stop face, and the or each finger being stressed by a tension spring tending to maintain it in the extended position in which the front stop face is orthogonal to the support plane, the or each finger further has an inclined face which is inclined in the opposite direction to the support plane and directed in the opposite direction to the chassis when the finger is in the extended position, such that the finger is able to pivot about the pivot axis against the spring towards its retracted position when a container moves towards the chassis and passes over the finger.

[0021] Preferably, for the or each pair of clamping elements, the element intended to come into contact against a face directed towards the chassis of the rearmost wire, called the rear element, has a rear stop face which extends in a plane perpendicular to the support plane and beyond the support plane.

[0022] Advantageously, for the or each pair of clamping members, the rear member also has a high stop face which protrudes beyond the rear stop face and extends, in use, in a plane arranged above the support plane and above a plane containing the upper end of the opposite member.

[0023] Thus, a wire mesh container resting horizontally on the support assembly and coming into contact with the rear member of the or each pair of members forming a clamp is blocked vertically on one side by the support assembly and on the other side by the or each face forming a top stop.

[0024] Preferably, the rear stop face is a flat face and the upper stop face is a flat face forming an angle between 90 and 135 degrees with the rear stop face.

[0025] Alternatively, the rear member or members could include a concave face complementary to the convex shape of a wire intended to be pinched by the pair of members forming a clamp, which concave face serves both as a rear stop and as a top stop.

[0026] It will be understood that the face forming a rear stop or any other face serving as a rear stop makes it possible to reference the positioning of a wire mesh container coming into contact with the rear member, despite positioning variations of such a container. container on the trolley on which it is stored, and therefore to facilitate the placement of this container, particularly in a machine.

[0027] Advantageously, the rear member or members further comprise a lower stop face extending from the rear stop face, the upper stop face and the lower stop face being arranged symmetrically with respect to the plane of the support assembly, and the front member or members comprise two ratchet fingers mounted around the same pivot axis and arranged symmetrically with respect to each other with respect to the plane of the support assembly. Thus, if the gripping tool is rotated 180 degrees, the roles of the upper stop face and the lower stop face can be reversed, and the front stop face of either of the two fingers is used.

[0028] Preferably, the clamping assembly comprises two pairs of clamping elements, the two pairs being spaced apart along the chassis.

[0029] In a particular embodiment, the actuation mechanism comprises, for each member, a lever supporting the member and mounted for rotational movement, the lever supporting the member of one or both pairs intended to come into contact with the face directed towards the chassis of the rearmost wire, referred to as the rear member, being connected to a first axis of rotation and the lever supporting the other member, referred to as the front member, of said pair being connected to a second axis of rotation, in the case of two pairs of members forming a clamp, the lever supporting the front member of the other pair being rotationally fixed to the lever connected to said first axis of rotation and the lever supporting the rear member of said other pair being rotationally fixed to the lever connected to said second axis of rotation, the two axes of rotation being coupled to each other by two pinions each mounted around an axis of rotation and meshing with each other,The actuation mechanism further comprises a linear actuator whose direction of action is perpendicular to the axes of rotation, the linear actuator being connected on one side to the chassis and on the other side to one of the levers.

[0030] Thus, a single linear actuator makes it possible to drive in synchronized rotation all the organs of the pair or pairs of organs forming the gripper.

[0031] In a particular embodiment, the linear actuator is a cylinder, in particular a double-acting cylinder.

[0032] Alternatively, the actuator of the actuation mechanism could be a non-linear actuator.

[0033] Each lever supporting a front member can be an angled lever having an opening turned towards the rear member of the same pair.

[0034] Advantageously, the support assembly comprises at least two support arms fixed to the chassis, parallel to each other and arranged on either side of the clamping assembly. In other words, the clamping assembly is arranged between the two arms of support.

[0035] Advantageously, each support arm can be extended by means of an extension attached removably to the free end of the arm and along its longitudinal axis, the face of the extension intended to be turned towards the container during use being level with the support surface. These extensions allow adaptation to wire mesh containers of different dimensions, in particular different widths.

[0036] Alternatively, each support arm could be a telescopic arm.

[0037] Furthermore, an extension forming an angle of less than 90 degrees with the longitudinal axis An extension can be attached to the side of the frame adjacent to the support assembly. This extension extends in the plane of the support arms, allowing it to cooperate, during use, with the underside of a bottom grid resting on the support arms. This extension may be cylindrical. It allows the container to be adapted to different dimensions and lengths of gridded containers.

[0038] In a particular embodiment, the gripping tool further comprises a detection unit carried by the chassis and arranged to detect a container located on the chassis support assembly side, the detection unit preferably comprising a camera equipped with a lens and a light source, the optical axis of the lens being located in the plane of the support assembly.

[0039] Thus, the camera can, for example, detect the presence of a container stored on a trolley and also identify the position of this stored container. The light source facilitates the detection of the container by illuminating it.

[0040] Preferably, the lighting source is configured to provide peripheral lighting around the camera lens, for example in the form of a ring of light.

[0041] The present invention also relates to a system for transferring a wire mesh or similar container comprising at least a wire mesh or similar bottom of which an underside face is at least partially accessible, which system is characterized by the fact that it comprises a robotic arm carrying a gripping tool as defined above, the robotic arm being capable of moving the gripping tool in three dimensions of space.

[0042] Preferably, the gripper tool is connected to the robotic arm via a pivoting base configured to allow the gripper tool to be turned around 180 degrees.

[0043] To better illustrate the object of the present invention, a particular embodiment thereof will be described below, with reference to the accompanying drawings. In these drawings:

[0044] [Fig. 1] is a perspective view of an example of a wire mesh container that the tool gripper according to the present invention is capable of manipulating;

[0045] [Fig.2] is a front perspective view of the gripping tool according to the present invention;

[0046] [Fig.3] is a top view of the gripper tool of [Fig.2];

[0047] [Fig.4] is a side view of the gripper tool support assembly of [Fig.2];

[0048] [Fig.5] is a top view of the clamping assembly alone of the gripper tool of the [Fig.2], which clamping assembly is in the inactive unlocking position;

[0049] [Fig.6] is a front perspective view of the clamping assembly of [Fig.5];

[0050] [Fig.7] is a top view, in section at the level of the median plane of the assembly support, showing a pair of organs forming a clamp in the active locking position;

[0051] [Fig.8] is a front perspective view of one of the organs of a pair of organs forming clamp, called rear organ, of the clamping assembly of the [Fig.5];

[0052] [Fig.9] is a perspective view of the other organ of a pair of organs forming clamp, called front member, of the clamping assembly of the [Fig.5], which front member is in extended position;

[0053] [Fig. 10] is a view in use of the gripping tool of [Fig. 3], an egg tray similar to that of [Fig. 1] being supported by the support assembly but not being locked in position on it by the clamping assembly; and

[0054] [Fig.11] is a view in use of the gripping tool of [Fig.10], the clamping assembly being in active locking position, only the rear pinched region of a bottom of a wire mesh container being shown for clarity.

[0055] In the description that follows, the terms "front" and "back" are to be considered in relation to the direction of advance of a gripping tool 1 equipping a transfer system according to the invention and moved towards a wire mesh container C to be handled.

[0056] Furthermore, in the description that follows, the terms "left" and "right", "high" and "low", "upper" and "lower" are used with reference to the orientation of the gripping tool 1 in use as shown in the Figures and considering a horizontal support plane; it is understood that depending on the orientation of the gripping tool 1 these terms may be interchanged.

[0057] The gripping tool 1 according to the present invention is intended to be mounted on a robotic arm (not shown) and arranged for handling a wire mesh container C comprising at least one bottom mesh C0 made of wire or similar material.

[0058] As can be seen in [Fig. 1], such a wire-mesh container C could be an egg tray-type container. Such an egg tray is a receptacle made of metal or plastic wires and intended to hold a plurality of eggs. This tray C includes a bottom mesh C0 intended to support the eggs. This bottom mesh C0 is delimited by a rectangular frame between which extend A plurality of transverse and longitudinal wires. This cage C also includes a wire mesh support Cl positioned above the base mesh CO, at a certain distance from it, whose rectangular frame is superimposed on the frame of the base mesh CO and which includes a plurality of transverse and longitudinal wires extending in the plane of the frame. The distance between the base mesh CO and the wire mesh support Cl is such that the eggs supported by the base mesh CO protrude above the wire mesh support Cl. The base mesh CO and the wire mesh support Cl are connected to each other by V-shaped wires welded to each of the two frames, as well as by V-shaped wires formed from one of the longitudinal wires of the base mesh CO and welded to a longitudinal wire of the wire mesh support CL. The meshes delimited by the longitudinal and transverse wires of the wire mesh support Cl have dimensions larger than those of the base mesh CO.These meshes are sized to receive each egg individually. Typically, such an egg tray C is stored on a sliding trolley (not shown), with the underside of the transverse end regions of the bottom grid CO resting on the trolley's slides. Thus, when stored, the egg tray C is accessible from below, at least in the area between the two transverse end regions.

[0059] Referring to Figures 2 to 4 and 10 and 11, it can be seen that the gripping tool 1 according to the preferred embodiment of the present invention comprises a chassis 2, a support assembly 3, a clamping assembly 4 and a detection unit 5.

[0060] The chassis 2 carries the support assembly 3, the clamping assembly 4 and the detection unit 5 and is intended to be connected to a robotic arm.

[0061] This chassis 2 comprises, on one side, a front wall 20, and on a second side, opposite the first side, a rear wall 21, two side walls 22 connecting the front wall 20 and rear wall 21 at their ends, an upper wall 23, and a lower wall 24 opposite the upper wall 23. One of the two side walls 22 is intended to be connected to a robotic arm, in particular the side wall 22 on the side of the detection unit 5. As previously stated, the upper wall 23 could be located below the lower wall 24 in the event of a 180-degree rotation of the gripper tool 1. The rear wall 21 is a flat wall which supports a portion of the feed passage 6 on its outer face directed opposite the front wall 20.The feed passage part 6 may include an angle bracket 60 fixed by screws to the rear wall 21 and a pivoting base 61 integral with the angle bracket 60 and suitable for allowing the passage of a robot harness, i.e. the set of cables and / or pipes ensuring the control and supply of the gripper tool 1. The pivoting base 61 is configured to allow a 180-degree rotation of the gripper tool 1. The front wall 20 may include several flat wall sections, including a first section extending. parallel to the rear wall 21 and a second section forming an angle with the rear wall 21. Several spacers 25 can extend between the inner face of the front wall 20 and the inner face of the rear wall 21, which inner faces are directed towards each other. The front wall 20 has cutouts at the support assembly 3, the clamping assembly 4, and the detection unit 5.

[0062] The support assembly 3 is intended to support a wire mesh container C from below.

[0063] In the illustrated embodiment, the support assembly 3 comprises two support arms 30 which are fixedly connected to the chassis 2. Each support arm 30 is in the form of a perforated rectangular plate having a free front longitudinal end and a rear longitudinal end fixed to the chassis 2. An extension 31, in the form of a solid plate of the same width and height as the arm 30, can be attached to the front end of each arm 30. The rear end of each arm 30 is fixed, in particular by screwing, to the rear wall 21 of the chassis 2. Thus, each arm 30 passes through a cutout made in the front wall 20 of the chassis 2. Each arm 30 is further fixed to the front wall 20 of the chassis 2 by means of fixing plates screwed on one side to the front wall 20 and on the other side to the arm 30.The two arms 30 are spaced apart by a desired distance. For example, one arm 30 is positioned at the end of the second section of the front wall 20 opposite the end on the side of the first section, and the other arm 30 is positioned at the first section. The two support arms 30 extend in the same plane, so that their upper and lower support faces, intended to cooperate with a container C to be handled, define a support plane. This support plane is perpendicular to the planes of the front wall 20 and rear wall 21 and is intended to be horizontal when a container C supported by the support assembly 3 is moved. The front end edges of the two arms 30 are arranged in the same plane, which is perpendicular to the support plane.

[0064] Alternatively, it would be possible to provide movable support arms between a retracted position and a deployed position in which the support arms define a support plane.

[0065] The clamping assembly 4 is capable of retaining, by clamping, a container C supported by the support assembly 3 so as to maintain it in position relative to the support assembly 3 in a simple and reliable manner.

[0066] In the embodiment shown, the clamping assembly 4 comprises two pairs 7G, ​​7D of clamping elements 70, 71 and an actuation mechanism 8 for these pairs 7G, ​​7D of clamping elements 70, 71. It should be emphasized that the number of pairs is not limited to two, so that the clamping assembly 4 could comprise a single pair of clamping elements, for example arranged at equal distances from each support arm 30, or more than two pairs of clamping elements.

[0067] As can be seen in Figures 5 to 7, each pair 7G, 7D of clamping elements 70, 71 comprises a rear element 70 and a front element 71 mounted so as to be able to be brought closer together or moved further apart. The rear elements 70 and front elements 71 are arranged and configured to each come into contact with a face of the peripheral wire on the frame side F of the bottom grid C0 of a container C supported by the support assembly 3, in particular with a face of the wire F forming the frame of the bottom grid C0 and positioned on the frame side 2, referred to as the extreme rear wire, in the case of an egg tray C as shown in [Fig. 1].

[0068] With particular reference to [Fig. 8], it can be seen that each rear member 70 is in the form of a single-piece block, having a rear stop face 70a, an upper stop face 70b, and a lower stop face 70c, all of which are oriented on the same side of the block, referred to as the front side (AV). The rear stop face 70a is a flat rectangular face extending in a plane orthogonal to the support plane. The rear stop face 70a projects on both sides of the support plane. Thus, if a support plane is placed horizontally, the rear stop face 70a projects above and below the support plane. In other words, if we consider a container C supported horizontally by the support arms 3, the rear stop face 70a is able to prevent a movement of the container C in this horizontal support plane and in the direction of the chassis 2.The rear stop face 70a is bounded at its upper end by the upper stop face 70b and at its lower end by the lower stop face 70c. These faces are flat, facing each other on either side of the support plane, and form an angle slightly greater than 90 degrees with the rear stop face 70a. In particular, these faces are inclined away from the support plane. The upper stop face 70b and the lower stop face 70c are arranged symmetrically with respect to the plane of the support arms 30. Thus, if we consider a support plane placed horizontally, the upper stop face 70b, which is the face that is above the support plane in the Figures representing the tool 1 in a given orientation, is able to prevent a movement of a container C supported horizontally by the support arms 30 in a vertical direction and opposite to the support arms 30.As previously stated, depending on the orientation of the tool 1, the lower stop face 70c can become the face that is above the support plane, namely the upper stop face in case of a 180-degree turn of the tool 1, and therefore become the face capable of preventing the container C from moving in a vertical direction and away from the support arms 30. In other words, depending on the orientation of the tool 1, either of the upper stop face 70b and the lower stop face 70c is capable of forming a vertical stop, with the container C being blocked vertically between the stop face. high and support arms 3.

[0069] Referring now to [Fig. 9], it can be seen that each front member 71 comprises two ratcheting fingers 710. Each finger 710 has a stop portion having a front stop face 710a and an inclined face 710b connected to each other and forming an angle of approximately 45 degrees. This stop portion is supported by a mounting portion. The mounting portion has, at its end opposite the stop portion, a hook to which one end of a tension spring 711 is connected. The other end of the spring 711 is connected to a finger support 712 located opposite the front stop face 710a. The mounting portion also has a through hole arranged between the hook and the stop portion. A pivot axis is received in the orifice of each of the two fingers 710, which orifices are coaxial, and is supported by two bearings integral with the finger support 712 and extending on either side of the fingers 710.The pivot axis extends in the plane of the support arms 30. Thus, the two fingers 710 are able to pivot about the pivot axis. More precisely, under the action of the tension springs 711, the two fingers 710 are placed in an extended position, in which the front stop faces 710a of the two fingers 710 extend in the same plane, which is orthogonal to the support plane and parallel to the plane of the rear stop face 70a, with one finger 710 protruding on one side of the support plane and the other finger 710 protruding on the other side of the support plane. Thus, in the extended position, the front stop faces 710a of a front member 71 are in a plane parallel to the plane of the rear stop face 70a of a rear member 70 of the same pair.When a container C slides along the support arms 30, towards the rear stop face 70a, it passes over the inclined face 710b of the finger 710, which protrudes beyond the support plane and thus above the support arms 30, assuming the support arms 30 are horizontal. The force applied by the container C on the inclined face 710b then opposes the force of the spring 711 and causes the finger 710 to pivot around its pivot axis into a retracted position. In this retracted position, the finger 710 of each pair of components 7G, ​​7D disappears below the support plane, specifically at the thickness of the support arms 30.

[0070] Each pair of gripper elements 7G, ​​7D is arranged near one of the support arms 30, the two pairs 7G, ​​7D being mounted between the two support arms 30. In other words, each rear element 70 is arranged in the space between a support arm 30, the front wall 20 of the frame 2, and the associated front element 71. For each pair 7G, 7D, the maximum spacing between the front element 71 and the rear element 70 of the same pair is limited by an indexing stop 32 integral with the associated support arm 30. This indexing stop 32 extends in the plane of the support arm 30 and has a surface oriented towards the frame 2 suitable for cooperating with the support of fingers 712. Upper and lower guides 33 can be fixed on either side of each indexing stop 32 so that the finger support 712 can be received between these guides 33. The two indexing stops 32 are arranged at an equal distance from the front end AV of each support arm 30.

[0071] The presence, on each rear member 70, of an upper stop face 70b and a lower stop face 70c arranged on either side of the rear stop face 70a and projecting on either side of the plane of the support arms 30, as well as the presence, on each front member 71, of two front stop surfaces 710a, each projecting on one side of the plane of the support arms 30 in the position extended from the fingers 710, makes it possible to grasp and move a container C by orienting the gripper tool 1 with either the upper wall 23 of the frame 2 facing upwards or the lower wall 24 of the frame 2 facing upwards, the frame 2 being able to pivot around its connection to the robotic arm at its side wall 22. In other words, a pair of gripper members 7G, ​​7D can constitute either a left pair than a right pair depending on the orientation of the gripping tool 1.Similarly, a face located in a high position in a first orientation of tool 1 can be in a low position in a second orientation of tool 1, and vice versa.

[0072] As can be seen in Figures 5 to 7, the actuation mechanism 8 of the two pairs of gripper members 7G, ​​7D comprises a single linear actuator 80, levers 81G, 81D, 82G, 82D, two rotation axes 83G, 83D and a pinion 85G, 85D.

[0073] Each rear component 70 and each front component 71 is carried by a lever. The levers 81G, 81D, 82G, 82D therefore comprise two rear levers 81G, 81D attached to the rear side (AR) of the block of each rear component 70 and two front levers 82G, 82D attached to the finger support 712 of each front component 71. Each front lever 82G, 82D is attached, at its end opposite to that carrying the associated component 71, to the rear lever 81D, 81G of the other pair of components. The four levers 81G, 81D, 82G, 82D extend in planes that are parallel to each other. Each front lever 82G, 82D is an angled lever with one elbow whose concavity faces the associated rear lever 81D, 81G, and whose two arms form an angle greater than 90 degrees with each other. Each rear lever 81G, 81D is an angled lever with two elbows, the first elbow at the rotation axes 83G, 83D, and the second elbow between the first elbow and the rear component 70.The concavity of the first elbow is turned towards the anterior organ 71 and the branches of this first elbow are oriented so as to circumvent the right axis of rotation 83D. The concavity of the second elbow is turned towards the rear AR, the two branches of the second elbow forming an angle greater than 90 degrees with each other.

[0074] Each of the two rear levers 81G, 81D has a through hole, with an axis orthogonal to the plane of the lever, at its end opposite the rear member 70. A rotation axis 83G, 83D is received in each of these holes, so that each rear lever 81G, 81D is fixed in motion to a rotation axis 83G, 83D. The two rotation axes 83G, 83D are carried by the chassis 2 by means of two support plates 84, namely a lower plate and an upper plate, fixed to the outer face of the front wall 20 of the chassis 2 and extending parallel to each other on the side of the support assembly 3 of the chassis 2. The ends of the rotation axes 83G, 83D pass through these plates 84 and are connected to these plates 84 by means of washers and nuts, ball bearings being mounted between each rotation axis 83G, 83D and the associated hole of each plate.Thus, the two rotation axes 83G, 83D are mounted to rotate freely around their axes, which are parallel to each other and perpendicular to the support plane.

[0075] With particular reference to [Fig. 6], it can be seen that a first pinion 85G is mounted around one of the rotation axes, called the left rotation axis 83G. This first pinion 85G is arranged between the lower support plate 84 and the rear lever 81D of one of the pairs of gripper components, called the right pair 7D. A second pinion 85D is mounted around a second rotation axis, called the right rotation axis 83D. This second pinion 85D is arranged between the upper support plate 84 and the rear lever 81G of the other pair of gripper components, called the left pair 7G. The first and second pinions 85G and 85D mesh with each other.

[0076] The single linear actuator 80 is a cylinder whose body 80a is received inside the frame 2 and whose rod 80b protrudes beyond the front wall 20 of the frame 2. This cylinder 80 is articulated between the frame 2 and one of the rear levers 81G, 81D. In particular, the body 80a of the cylinder 80 is connected to the inner face of the rear wall 21 of the frame 2 and the rod 80b is connected to the rear lever 81G of the left pair of gripper elements 7G.

[0077] Thus, due to the configuration of the levers 81G, 81D, 82G, 82D and the connection between the rear lever 81G, 81D of one pair and the front lever 82G, 82D of the other pair, an extension of the rod 80b of the cylinder 80 causes a displacement of the rear left lever 81G and therefore of the rear member 70 of the left pair 7G towards the front member 71 of the left pair 7G, as well as a displacement of the front right lever 82D, connected to the rear left lever 81G, towards the rear member 70 of the right pair 7D. Simultaneously, due to the gears 85G, 85D mounted on the rotation axes 83G, 83D and the connection of each rear lever 81G, 81D with one of the rotation axes 83G, 83D, the rotation of the right rotation axis 83D in a first direction of rotation, under the effect of the movement of the left rear lever 81G, causes the rotation of the left rotation axis 83G in a second direction of rotation, opposite to the first direction of rotation. This rotation of the left axis of rotation 83G in turn causes a displacement of the right rear lever 81D, which is attached to it, towards the front member 71 of the right pair 7D, as well as a displacement of the left front lever 82G, attached to the right rear lever 81D, towards the rear member 70 of the left pair 7G. In other words, an extension of the rod 80b of the cylinder 80 causes the clamping members 70 and 71 of the two pairs 7G and 7D to move together simultaneously and identically. The stroke of the cylinder 80 is adjusted so that the approach of the clamping elements 70, 71 allows the container C, in particular the rearmost wire F of the bottom grid C0 of the container C, to be clamped between the clamping elements 70, 71. Such an approach for clamping purposes is called the active locking position (Figures 7 and H).

[0078] Conversely, a retraction of the rod 80b of the cylinder 80 causes a separation between the clamping elements 70, 71 of the two pairs 7G, ​​7D simultaneously and identically, until the front elements 71 come to a stop against their indexing stop 32, as seen in Figures 2 and 3. This position of the clamping elements 70, 71, in which the front elements 71 and rear elements 70 of each pair 7G, 7D do not allow the clamping of a wire F of the container C is called the inactive unlocking position.

[0079] The detection unit 5 allows the position of the container C to be manipulated to be determined, in particular the position of the lower face of this container C. The detection unit 5 includes a camera 50 and a light source 51.

[0080] As can be seen in [Fig. 3], the camera 50 is mounted in the interior space of the chassis 2, near one of the side walls 22. In particular, the camera 50 is attached to the front of a camera support plate fixed to the inner faces of the rear wall 21 and the left side wall 22. The camera 50 is directed towards the space located at the front AV of the front wall 20 of the chassis 2, and therefore, during use, towards a container C to be handled. As can be seen in [Fig. 4], the optical axis A0 of the lens of the camera 50 lies in the plane of the support arms 30 and extends substantially parallel to the longitudinal axis of each support arm 30. The light source 51 is fixed to the camera support plate. The light source 51 is arranged around the lens of the camera 50.

[0081] Regarding the dimensions of the gripping tool 1, these are linked to the dimensions of the containers C that will be handled. By way of non-limiting example, if the gripping tool 1 is intended to handle containers C with a length strictly greater than 510 mm, the gripping tool 1 could have the following dimensions: a maximum depth (between the free end of a support arm 30 and the feed passage 6) of 549 mm, a length of 782 mm, a maximum height of 184 mm, with a chassis 2 having a maximum depth (between the side of support arm 30 of chassis 2 and the opposite side thereof) of 115 mm, and with a support assembly 3 having a distance between the two support arms 30 of 370 mm and a width of each support arm 30 of 70 mm. It is understood that these dimensions could be reduced or increased.

[0082] In use, the gripping tool 1 is carried by a robotic arm of a transfer system, which robotic arm, well known per se, is capable of moving the gripping tool 1 in three dimensions. The gripping tool 1 is also capable of being pivoted relative to the robotic arm, so that the support plane is defined by one or the other of the support faces of the support arms 30. The gripping tool 1 is implemented according to a method as described below in order to transfer a wire mesh container C from a first zone, for example a storage zone, such as a sliding trolley on which one or more containers C are stored, to a second, desired receiving zone.

[0083] The method according to the invention comprises a first step of determining the position of the container C to be handled, a second step of positioning the gripping tool 1 relative to the lower face of the bottom grid C0 of the container C to be handled, a third step comprising ensuring the support of the container C by the support assembly 3 ([Fig. 10]), and a fourth step comprising ensuring the holding in position of the container C on the support assembly 3 using the clamping assembly 4 ([Fig. 11]).

[0084] More specifically, during the first step, in the case where the position of the container C is not known in advance, the detection unit 5 is used, in a manner known per se and which it is therefore not necessary to describe here in detail, to determine the position of the container C.

[0085] During the second step, once the position of container C has been determined, the gripping tool 1 is positioned relative to the detected container C, using the robotic arm, such that the support faces of the two support arms 30 are aligned with the accessible lower face of the bottom grid C0 of the container C to be gripped. At this step, the clamping assembly 4 is in the inactive release position.

[0086] During the third step, as can be seen in [Fig. 10], the support arms 30 are moved, by movement of the robotic arm, under the bottom grid C0 so as to slide the container C along the support arms 30 until the container C rests on both support arms 30 with the rearmost wire F of the bottom grid C0 interposed between the rear member 70 and the front member 71 of each of the two pairs of gripper members 7G, ​​7D. During the movement of the container C along the support arms 30 towards the front wall 20 of the frame 2, for each pair 7G, 7D of gripper members 70, 71, the finger 710 which is Initially in the extended position above the support plane, the container C is pushed towards its retracted position by the application of the weight of the container C against the inclined face 710b of the finger 710 as the rearmost wire F passes over said inclined face 710b. Once the rearmost wire F of the container C is interposed between the front stop face 710a of said finger 710 and the rear stop face 70a of the associated rear member 70, the finger 710 returns to the extended position under the effect of the spring 711, thus preventing any forward movement of the container C. In other words, the rearmost wire F is located between the pairs 7G, ​​7D of the clamping members 70, 71.

[0087] Then, during the fourth step, as can be seen in [Fig. 1 1], the cylinder 80 is actuated in such a way that the clamping members 70, 71 of each pair 7G, 7D are moved towards each other until they clamp the rearmost wire F between the rear stop face 70a of the rear member 70 and the front stop face 710a of the associated front member 71. In this active locking position of the clamping assembly 4, the container C rests on the support arms 30 and the wire F of the bottom grid C0 tightened by the clamping elements 70, 71 is locked between the support arms 30, the upper stop face 70b of the rear elements 70, the rear stop face 70a of the rear elements 70 and the front stop face 710a of the front elements 71. Thus, considering a horizontal support plane, the container C is locked both vertically and horizontally.The transfer of container C between the two zones can therefore be carried out safely.

[0088] It is readily understood that placing the container C in the desired receiving area is equally simple, since it is enough to place the container C on a suitable support in the desired receiving area, then move the clamping assembly 4 to its inactive release position by retracting the rod 80b of the cylinder 80, and finally move the arms 30 vertically downwards so as to disengage them from the container C and thus prevent the fingers 710 from obstructing the withdrawal of the arms 30 from the receiving area. Once the container C has been placed in the desired receiving area, the gripping tool 1 can be repositioned in the storage area for handling another container C.

[0089] It is understood that the particular embodiment just described has been given by way of example and not limitation, and that modifications may be made without departing from the scope of the present invention.

Claims

1.

2. Demands A gripping tool (1) intended to be mounted on a robotic arm and arranged for handling a wire mesh container (C) comprising at least one wire mesh base (CO) or similar material, the lower face of which is at least partially accessible, the gripping tool (1) comprising a frame (2) which carries, on a first side thereof, a support assembly (3) defining a support plane for a container (C) and configured to be able to come into contact with an underside of a wire mesh base (CO) and to support a container (C), characterized in that the gripping tool (1) further comprises a clamping assembly (4) carried by the frame (2), on the first side thereof, and comprising at least one pair (7G, 7D) of gripper members (70, 71) and an actuation mechanism (8) able to move the gripper members (70, 71) relative to each other so as to move, in use,the clamping assembly (4) between an inactive unlocking position in which the clamping members (70, 71) are separated from each other so as to allow movement of a container (C) relative to the support assembly (3) on which it rests, and an active locking position in which the clamping members (70, 71) are able to clamp a wire (F) or similar element of the bottom grid (CO) so as to allow the container (C) to be held in position on the support assembly (3). Gripping tool (1) according to claim 1, characterized in that, for one or each pair (7G, 7D) of gripper members (70, 71), the two members (70, 71) are mounted to rotate only relative to the frame (2), at the level of the support plane, about axes of rotation (83G, 83D) perpendicular to the support plane, such that they can be brought closer together or further apart by the actuation mechanism (8). In use, bringing the gripper members (70, 71) closer together brings the clamping assembly (4) into the active locking position in which the gripper members (70, 71) are able to grip the wire (F) on the frame side (2) or similar wire of the bottom grid (C0) resting on the support assembly (3), referred to as the rearmost wire (F), and the member (71) intended to come into contact against a face directed opposite to the chassis (2) of the extreme rear wire (F), called the front element (71),is also mounted mobile between a retracted position in which the front organ (71) is hidden beneath the, support plane and an exit position in which the front member (71) protrudes beyond the support plane.

3. Gripping tool (1) according to claim 2, characterized in that, for one or each pair (7G, 7D) of gripper members (70, 71), the front member (71) comprises at least one ratcheting finger (710) having a front stop face (710a), the finger or fingers (710) being pivotally mounted about a pivot axis located in the plane of the support assembly (3) and parallel to the plane of the front stop face (710a), and the finger or fingers (710) being tensioned by a tension spring (711) tending to maintain it in the extended position in which the front stop face (710a) is orthogonal to the support plane, the finger or fingers (710) further having an inclined face (710b) which is inclined away from the support plane and directed away from the frame (2) when the finger (710) is in the out position,such that the finger (710) is able to pivot around the pivot axis against the spring (711) towards its retracted position when a container (C) moves towards the chassis (2) and passes over the finger (710).

4. Gripping tool (1) according to any one of claims 2 and 3, characterized in that, for the or each pair (7G, 7D) of gripper members (70, 71), the member (70) intended to come into contact against a face directed towards the frame (2) of the rearmost wire (F), referred to as the rear member (70), has a rear stop face (70a) which extends in a plane perpendicular to the support plane and beyond the support plane.

5. Gripping tool (1) according to claim 4, characterized in that, for the or each pair (7G, 7D) of gripper members (70, 71), the rear member (70) also has a high stop face (70b) which protrudes beyond the rear stop face (70a) and extends, in use, in a plane arranged above the support plane and above a plane containing the upper end of the opposite member (71).

6. Gripping tool (1) according to any one of claims 1 to 5, characterized in that the clamping assembly (4) comprises two pairs (7G, 7D) of gripper-forming elements (70, 71), the two pairs (7G, 7D) being spaced apart along the frame (2).

7. Gripping tool (1) according to claim 2, characterized in that the actuation mechanism (8) comprises, for each member (70, 71), a lever (81G, 81D, 82G, 82D) supporting the member (70, 71) andmounted movable for rotation, the lever (81G; 81D) supporting the member (70) of one or more pairs (7G, 7D) intended to come into contact against the face facing the chassis (2) of the rearmost wire (F), called the rear member (70), being connected to a first axis of rotation (83G; 83D) and the lever (82G; 82D) supporting the other member (71), called the front member (71), of said pair being connected to a second axis of rotation (83G; 83D), in the case of two pairs (7G, 7D) of members forming a clamp (70, 71), the lever (82G; 82D) supporting the front member (71) of the other pair being rotationally fixed to the lever (81G; 81D) connected to said first axis of rotation (83G; 83D) and the lever (81G; 81D) supporting the rear organ (70) of said other pair being rotationally fixed to the lever (82G; 82D) connected to said second axis of rotation (83G;83D), the two axes of rotation (83G, 83D) being coupled to each other by two pinions (85G, 85D) each mounted around an axis of rotation (83G, 83D) and meshing with each other, the actuation mechanism (8) further comprising a linear actuator (80) whose direction of action is perpendicular to the axes of rotation (83G, 83D), the linear actuator being connected on one side to the chassis (2) and on the other side to one of the levers (81G, 81D, 82G, 82D).;

8. Gripping tool (1) according to any one of claims 1 to 7, characterized in that the support assembly (3) comprises at least two support arms (30) attached to the frame (2), parallel to each other and arranged on either side of the clamping assembly (4).

9. Gripping tool (1) according to any one of claims 1 to 8, characterized in that it further comprises a detection unit (5) carried by the chassis (2) and arranged to detect a container (C) located on the support assembly (3) side of the chassis (2), the detection unit (5) preferably comprising a camera (50) equipped with a lens and a light source (51), the optical axis (A0) of the lens being located in the plane of the support assembly (3).

10. A system for transferring a wire mesh container (C) or the like comprising at least one bottom wire mesh (C0) or the like, the lower face of which is at least partially accessible, which system is characterized in that it comprises a robotic arm carrying a gripping tool (1) according to any one of claims 1 to 9, the robotic arm being capable of moving the gripping tool (1) in three dimensions of space.

Images