METHOD FOR ATTACHING A TOOL TO A ROBOT ARM AND ASSOCIATED ARRANGEMENT

Description

TECHNICAL FIELD OF THE INVENTION

[0001] The invention relates, in general, to the technical field of attaching a tool to a robot arm.

[0002] The invention relates more specifically to a method of fixing a tool onto a robot arm and to an assembly. PREVIOUS STATE OF THE ART

[0003] In robotics, it's common to need several different tools to perform a series of tasks. However, it's often necessary to limit the number of tools at the end of the robot arm to reduce weight, size, or the risk of collision, for example. This limitation may lead to the use of a single tool carried by the robot arm, making a tool changer essential.

[0004] As is well known, most industrial tool changers are either automatic or manual.

[0005] In the first case, it is generally necessary to use a power source, very often pneumatic, and to install an actuator at the tool changer to ensure secure tool engagement. These constraints impose an increase in weight, control complexity, wiring, etc.

[0006] In the case of a manual tool changer, it becomes necessary to call upon a qualified operator, often equipped with a specific tool, to lock and unlock the tool on the changer. This reduces the level of automation and implies the use of labor for additional, low-value-added tasks.

[0007] Documents CN 111 618 897 A and WO 2011 / 019742 A1 describe a method of fixing a tool on a robot arm, known from the prior art. DESCRIPTION OF THE INVENTION

[0008] The invention aims to remedy all or part of the disadvantages of the prior art by proposing in particular a solution enabling a robot to change its tool quickly so as to provide a time saving in the production chain, automatically so as to gain autonomy, and passively so as not to depend on additional wiring or energy.

[0009] To achieve this, according to a first aspect of the invention, a method for attaching a tool to a robot arm is proposed, comprising at least the following steps: a transition from a relative approach position to a relative fixed position by relative translational movement between the tool and the robot arm parallel to a reference axis of the robot arm such that the reference axis of the robot arm is coaxial with a reference axis of the tool, and such that tenons are inserted into associated notches, each notch being associated with a sub-assembly of the tool and the robot arm and with one of the tenons attached to the other sub-assembly of the tool and the robot arm, then a transition from the relative fixed position to a relative assembly position by relative rotational movement between the tool and the robot arm around the axis of rotation such that each of the tenons fits into a circumferential extension of the associated notch and is held axially therein,then a locking in relative assembly position by relative translational movement parallel to the reference axis of the robot arm, between the assembly formed by the tool and the robot arm in the relative assembly position and at least one locking piece such that shims attached to the locking piece enter the notches and lock the tenons in the locked position.

[0010] Thanks to this combination of features, attaching the tool arm to the robot arm is a very simple mechanical process. This continuous movement of successive translation and rotation is indeed easy and quick to implement.

[0011] In one embodiment, during the transition from the relative position of the fixed part to the relative position of the assembled part, each tenon fits snugly into a circumferential extension of its associated notch. This feature allows for a tight fit of the assembled parts, particularly the tool relative to the robot arm.

[0012] In one embodiment, the transition from the relative approach position to the relative fixed position is achieved by motorized movement of the robot arm, with the tool held in a support. A simple movement of the robot arm controlled by the robot thus allows this simple movement to be implemented.

[0013] According to one embodiment, the transition from the relative position of embedding to the relative position of assembly is achieved by motorized movement of the robot arm, the tool being held in the support.

[0014] According to one embodiment, the locking in the relative assembly position is done by motorized movement of the robot arm, the locking piece being held in the support.

[0015] These successive movements can thus be carried out by the robot itself while the tool is held on a support positioned within the robot's operating range. Multiple tools, each held in a dedicated support, allow the same robot to attach the necessary tool, or even change tools when needed.

[0016] In one embodiment, the fastening process includes an operation to release the locked assembly consisting of the robot arm and the tool in the assembly position, and the locking piece in the locked position, by translating the robot arm relative to the support in a direction perpendicular to the reference axis. Again, this movement is achieved by motorized movement of the robot arm, successively to the steps that enabled the tool to be fixed to the robot arm. Indeed, the motorized movement of the robot arm directly drives the tool in the movement to which it is fixed, the tool being thus displaced from its support, which is held fixed relative to a frame.

[0017] According to one embodiment, the locking piece includes a ring.

[0018] In one embodiment, the support has the shape of a fork with two retaining fingers. This allows for a better distribution of forces between the support and the tool.

[0019] According to one embodiment, the tenons are all attached to the same sub-assembly among the robot arm and the tool.

[0020] In one embodiment, the tenons are equidistant. This characteristic allows for a tool that is not indexed.

[0021] Alternatively, and according to one embodiment, the tenons are not equidistant. In such a configuration, this allows the tool to be indexed in an angular position.

[0022] According to another aspect of the invention, it relates to an assembly of a tool on a robot arm characterized in that the robot arm and the tool are mobile between: a relative approach position and a relative fixed position by relative translational movement between the tool and the robot arm parallel to a reference axis of the robot arm such that, in the relative fixed position, the reference axis of the robot arm is coaxial with a reference axis of the tool, and tenons penetrate associated notches, each of the notches being associated with a subset of the tool and the robot arm and with one of the tenons integral with the other subset of the tool and the robot arm, the relative fixed position and a relative assembly position by relative rotational movement between the tool and the robot arm around the axis of rotation such that, in the relative assembly position, each of the tenons is housed in a circumferential extension of the associated notch with respect to the relative fixed position and is axially retained therein, the assembly further comprising at least one locking piece configured to ensure locking in relative assembly position by relative translational movement parallel to the reference axis of the robot arm, between the assembly formed by the tool and the robot arm in the relative assembly position and the locking piece so that, in a locking position, wedges attached to the locking piece penetrate the notches and lock the tenons in position.

[0023] According to one embodiment, at least part of the tenons and / or notches has an inclined wall having at least one axial component so as to allow adjustment of the tenons housed in a circumferential extension of the associated notch when passing from the relative position of embedment to the relative position of assembly.

[0024] According to one embodiment, the tenons are all attached to the same sub-assembly among the robot arm and the tool, preferably the robot arm, and the notches are all attached to the same other sub-sub-assembly among the robot arm and the tool, preferably the tool.

[0025] According to one embodiment, the locking piece is mounted securely in a sliding connection to one of the sub-assemblies among the robot arm and the tool, preferably the sub-assembly to which the tenons are attached.

[0026] According to one embodiment, the locking piece includes a ring, the shims preferably being radially projecting with respect to a reference axis of the locking piece.

[0027] In one embodiment, the assembly includes at least one means for axially elastic locking the locking piece in the configured locking position such that the locking piece is released from the locking position if an axial force exceeding a predetermined threshold axial force is applied relative to the assembly formed by the tool and the robot arm in the relative assembly position and the locking piece. In this way, the locking piece is held in the locked position until a predetermined force is applied to it relative to the assembly formed by the tool and the robot arm in the relative assembly position.

[0028] According to one embodiment, the axial elastic locking means for the locking piece in the locked position comprises at least one ball elastically constrained by a spring. BRIEF DESCRIPTION OF THE FIGURES

[0029] Other features and advantages of the invention will become apparent from the following description, with reference to the attached figures, which illustrate: figure 1 : a view of a cobot equipped with a robot arm according to an embodiment of the invention; figure 2 : a view of an end portion of a robot arm and assembly according to an embodiment, in a position in which a tool is held in a support; figure 3 : a view of the end portion of the robot arm and the assembly according to the embodiment of the figure 2 , in a position in which the tool is free from the support; figure 4 : an isometric perspective view of a relative approach position between the tool and the robot arm; figure 5 : a front view of the figure 4 ; figure 6 : an isometric perspective view of a relative position of embedding between the tool and the robot arm; figure 7: a front view of the figure 6 ; figure 8 : an isometric perspective view of a relative assembly position between the tool and the robot arm; figure 9 : a front view of the figure 8 ; Figure 10 : an isometric perspective view of a locking position of the tenons in notches; figure 11 : a front view of the Figure 10 ; figure 12 : an axial cross-sectional view of the Figure 10 ; figure 13 : an exploded view of the assembly according to this embodiment; figure 14 : an axial cross-sectional view of the figure 13 .

[0030] For clarity, identical or similar elements are identified by identical reference symbols across all figures. DETAILED DESCRIPTION OF A METHOD OF IMPLEMENTATION

[0031] There figure 1 illustrates a view of a robot 1, in particular here of a cobot equipped with an arm 10 robot 1.In other words, this implementation involves a so-called "collaborative" robot, meaning one that works in a shared space and is configured to interact with a person. The cobot is generally dependent on the operator's movements. In an application to an automated production line, for example, several cobots may work alongside human operators, or in their immediate vicinity.

[0032] The robot 1 present, at a distal end of his arm 10 articulated, an interface 10' configured to secure a tool 20. Its characteristics, particularly its dimensions, may vary depending on the shape and dimensions of the tools. 20 Don't miss out.

[0033] The tools 20 are arranged in a zone or workspace of the robot 1or cobot. In particular, to limit the number of tools 20 carried by the arm 10 robot 1, several tools 20 intended to be used alternately by the arm 10 robot 1 are each stored on a medium 60 fixedly mounted relative to a frame (see for example the figures 2 and 3 In this way, the arm 10 robot 1 carries a single tool 20 dedicated to a specific task and changes tools 20 before moving on to a different task. Alternating tools 20 It therefore depends on the alternation of tasks to be performed.

[0034] The tool 20 includes an interface 20' configured to cooperate with the interface 10' arm 10 robot 1. Each of the interfaces 10' And 20' arm 10 robot 1 and the tool 20,respectively, may be a single unit with them or may also have the form of a piece specifically attached to said arm 10 robot 1 and / or the tool 20. With reference to the figures described here, we will speak interchangeably of interfaces 10' And 20' or the arm 10 robot 1 and the tool 20.

[0035] The tool 20 and the arm 10 robot 1, or at least their interfaces 10' And 20' associated assembly components are thus configured to form an assembly together. 100 adapted to be able to be assembled and disassembled easily and quickly while presenting a simple structure, by following a sequence of adapted movements.

[0036] In particular, the assembly includes a plurality of tenons 30 configured to cooperate with notches 40 associated. Each of the tenons30 is integral to one of the subsets within the tool 20 and the arm 10 robot 1 while the notches are carried by the other sub-assembly within the tool 20 and the arm 10 robot 1. In this way, the cooperation of each of the tenons 30 with a notch 40 The associated interface allows the assembly of the two interfaces. 10' And 20' one with the other, and therefore the assembly of the tool 20 on the arm 10 robot 1.

[0037] The cooperation of the tenons 30 with the notches 40 The associated components ensure at least one axial locking of the assembly. 100, The rotational locking mechanism is ensured by a locking piece. 50.

[0038] In particular, the interface 20' of the tool 20 includes a body 21exhibiting an overall cylindrical shape of reference axis A2. The interface 20' of the tool 20 also includes a plurality of tenons 30, four in this mode of embodiment, distributed circumferentially around the body 21 cylindrical interface 20'. In particular, the tenons 30 are here equally distributed, that is to say, distributed homogeneously around the circumference of the body 21 generally cylindrical.

[0039] The tenons 30 are formed by radial projections relative to the reference axis A2 extending outwards, in the direction of a move away from the reference axis A2, from the body 21 of the interface 20'.These projections extend circumferentially over a predetermined angular sector, here of 45 degrees. Each projection is circumferentially spaced from another adjacent projection by a space extending over an angular sector also of 45 degrees.

[0040] In such a configuration, the tenons 30 are all part of the same subset within the arm 10 robot 1 and the tool 20, namely, the tool 20, and in particular here of the interface 20' of the tool 20.

[0041] The interface 10' arm 10 robot 1 It includes a body with notches. 40, There are four of them here. The assembly has the same number of tenons. 30 how many notches 40, each tenon 30 being associated with a notch 40. The interface 10' arm 10 robot 1 includes a base11 generally cylindrical with a reference axis A1, itself located in the extension of the arm 10 robot 1 arm 10 robot 1 which carries said interface 10'.

[0042] Each notch 40 presents an "L" shape: a first part 401 of the notch 40 extends parallel to the reference axis A1 arm 10 robot 1, and a second part 402 of the notch 40 extending circumferentially with respect to the reference axis A1 arm 10 robot 1 from the first part.

[0043] In such a configuration, the notches 40 are all part of the same subset within the arm 10 robot 1 and the tool 20, different here from the one bearing the tenons 30, namely the arm 10 robot 1,and in particular the interface 10' arm 10 robot 1.

[0044] The notches 40 are delimited by brackets 45 extending circumferentially over a predetermined angular sector, here approximately 45 degrees or slightly less. Each bracket 45 is spaced circumferentially from another hook 45 adjacent by a circumferential space or gap extending over an angular sector also of approximately 45 degrees, or slightly greater.

[0045] Each hook 45 includes a base 46 extending axially with respect to the reference axis A1 from the base 11 of the interface 10' arm 10 robot 1. Each hook 45 also includes a head 47 extending radially from the base 46associated inwards, that is to say in the direction of a move towards the reference axis A1, from the base 46 associated with the interface 10'.

[0046] The first parts 401 axial notches 40, extending parallel to the reference axis A1 arm 10 robot 1, are circumferentially delimited by the brackets 45 themselves. In this way, the circumferential spaces between each of the brackets circumferentially delimit the first parts 401 axial notches 40.

[0047] The second parts 402 circumferential notches 40, which extend circumferentially with respect to the reference axis A1 arm 10 robot 1 from the first part 401 associated, are delimited by brackets 45.The axial distance taken between the base 11 of the interface 10' arm 10 robot 1 and the head 47 of each hook 45 is at least equal to, or even slightly greater than, the thickness of the tenon 30 associated so that each hook 45 delimits, with the base 11 of the interface 10', the second part 402 circumferential of one of the notches 40.

[0048] Assembling the tool 20 and the arm 10 robot 1 will be better understood with the following description of the tool fixing process 20 on the arm 10 robot 1.

[0049] In the first step of the tool fixing process 20 on the arm 10 robot 1,The transition from a relative approach position to a relative fixed position is achieved by relative translational movement. M1 between the tool 20 and the arm 10 robot 1 parallel to the reference axis A1 arm 10 robot 1 so that the reference axis A1 arm 10 robot 1 either coaxial with the reference axis A2 of the tool 20, and in such a way as to allow tenons to penetrate 30 in the notches 40 associated. As described previously, each of the notches 40 is associated; on the one hand, with a subset of the tool 20 and the arm 10 robot 1, namely, here, the arm 10 robot 1 and, on the other hand, to one of the tenons 30 in solidarity with the other subset within the tool 20 and the arm 10 robot 1,namely, the tool 20.

[0050] The relative position of approach between the tool 20 and the arm 10 robot 1 and more specifically illustrated on the Figures 4 and 5 The relative position of the tool's embedment 20 and the arm 10 robot 1 is illustrated in detail on the Figures 6 and 7 .

[0051] In these positions, the reference axes A1 And A2 are coaxial and correspond to a reference axis A of the assembly 100.

[0052] During the relative translational motion M1 between the tool 20 and the arm 10 robot 1 the tenons 30 enter the notches 40 associated, that is to say in particular that each tenon 30 comes to translate into one of the first parts 401 axial notches 40.

[0053] During this first stage, the transition from the relative approach position to the relative fixed position is achieved by motorized movement of the arm 10 robot 1, the tool 20 being held in the support 60. In this way, the control of the arm's movement alone 10 robot 1 allows this step to be implemented. The robot thus controls the movement of its interface in space. 10' by a combination of translational and / or rotational movements.

[0054] In a second step, following the first step, the relative fixed position is moved to a relative assembled position by relative rotational movement. M2 between the tool 20 and the arm 10 robot 1 around the axis of rotation so that each of the tenons 30 come to be housed in a circumferential extension41 of the notch 40 associated and is held axially there. Each circumferential extension is here constituted by the second part 402 from one of the notches 40.

[0055] The relative assembly position between the tool 20 and the arm 10 robot 1 is illustrated in detail on the figures 8 and 9 .

[0056] During this step, the transition from the relative position of embedding to the relative position of assembly is achieved by motorized movement of the arm 10 robot 1, successively and in the continuity of the translational movement M1 from the first step, the tool 20 being still held in the support 60. In this way, the control of the arm's movement alone 10 robot 1 This allows this step to be implemented. The robot then controls the movement of its interface. 10'by a rotation around its reference axis A1, coaxial here with the reference axis A of the assembly 100. The tool 20 being held fixed in its support 60, the movement of the interface 10' is therefore a rotation of the interface 10' relatively compared to the tool 20.

[0057] During this relative rotational movement M2 between the tool 20 and the arm 10 robot 1, during the transition from the relative fixed position to the relative assembly position, the assembly 100 is configured so that each of the tenons 30 fits snugly into a circumferential extension 41 of the notch 40 associated. For this, at least one of the tenons 30, preferably all the tenons 30,As illustrated in the figures, they exhibit a thickness, taken axially, that increases from a distal end to a proximal end, such that as the relative rotational movement M2 between the tool 20 and the arm 10 robot 1 unfolds, each tenon 30 penetrates into circumferential extension 41 of the notch 40 until it is axially clamped within it. In other words, it shrinks in the circumferential direction of rotation towards the relative assembly position. In this embodiment, the tenons each have a wall 31 axial end opposite the base 11 of the interface 10' arm 10 robot 1, this wall 31 being inclined with respect to the reference axis A1.

[0058] Alternatively or in addition, the circumferential extension41 of the notch 40 associated, in particular here the second part 402 of each of the notches 40 presents a shape whose radial thickness decreases in the circumferential direction of rotation towards the relative assembly position.

[0059] The cooperation of the tenons 30 with the notches 40 The associated components allow for axial locking of the assembly. 100, between the tool 20 and the arm 10 robot 1. The tenons 30 are indeed blocked, in a sense by the head 47 of each of the hooks 45 partially defining the notch 40 associated and in the other direction by the base the base 11 of the interface 10' arm 10 robot 1 partially defining the notch 40 associated. Of course, such a configuration can vary, the base 11for example, it can be replaced by axially offset projections on each of the heads. 47 hooks 45 partners.

[0060] The assembly 100 it also includes at least one locking piece 50, unique in the illustrated embodiment, and configured to ensure locking in the relative assembly position by relative translational movement M3 parallel to the reference axis A1 arm 10 robot 1. This translational movement M3 is relative here between, on the one hand, the set formed by the tool 20 and the arm 10 robot 1 in the relative assembly position and, on the other hand, the locking piece 50 so that, in a locked position, the wedges 51 attached to the locking piece 50 enter the notches 40and lock the tenons into position 30.

[0061] During this translation M3, the wedges 51 delve more specifically into the first part 401 of the notch 40, the tenons 30 being then housed in the second part 402 of the notch 40. Preferably, each wedge 51 extends circumferentially over a predetermined angular sector, here approximately equal to that of the first part 401 of the notch 40 associated, namely approximately 45 degrees or slightly less. Each wedge 51 is spaced circumferentially from another wedge 51 adjacent by a space extending over an angular sector also of 45 degrees or slightly greater.

[0062] This third step ensures that rotation is blocked thanks to the locking piece. 50, of the tool 20 in relation to the arm 10robot 1 in the relative assembly position, that is, when each of the tenons 30 is housed in the circumferential extension 41 of the notch 40 associate.

[0063] The tool's locking position 20 with the arm 10 robot 1 by the locking piece 50 is illustrated in detail on the figures 10, 11 And 12 .

[0064] During this step, the locking piece 50 is translated according to the translational movement M3 parallel to the reference axis A1 arm 10 robot 1. In this embodiment, the locking piece 50 is mounted in conjunction with the tool, in particular here in conjunction with the interface 20' of the tool 20. In particular, the locking piece 50 is mounted securely in a sliding connection relative to the tool20.

[0065] The locking piece 50 presents a shape delimiting a closed contour surrounding the interface 20' of the tool 20 around its reference axis A2. The locking piece 50 includes a ring 52 defining an annular base, the wedges 51 being radially salient with respect to a reference axis A5 of the locking piece 50, coaxial to the reference axis A2 of the interface 20' of the tool 20. The radial projection of each of the wedges 51 is directed from the ring 52 inwards, that is to say in a direction of moving towards the reference axis A2.

[0066] Locking in the relative assembly position is also achieved by motorized movement of the arm. 10 robot 1, successively and in continuity with the rotational movementM2 of the second step, the tool 20 being still held in the support 60. In this way, the control of the arm's movement alone 10 robot 1 This allows this step to be implemented. The robot then controls the movement of its interface. 10' by a translation along its reference axis A1, coaxial here with the reference axis A of the assembly 100.

[0067] In particular, the tool 20 is held fixed in its support 60 at the locking piece 50 herself. The support 60 has the shape of a fork with two retaining fingers 61. Each of the restraining fingers 61 presents a form of open rails placed opposite each other in which the locking piece is mounted in a sliding connection 50 along an axis radial to the reference axis A2 of the interface 20'of the tool 20. The locking piece 50 is supported 60 and can be mobile relative to the support only along this radial axis relative to the reference axis A of the assembly 100.

[0068] Thus, in a fourth step, an operation is carried out to release the locked assembly consisting of the arm 10 robot 1 and the tool 20 in the assembled position, and the locking piece 50 in the locked position. This release operation is achieved by translation of the arm 10 robot 1 compared to the support 60 in one direction M4 perpendicular to the reference axis.

[0069] This direction M4 corresponds to the degree of freedom of the sliding joint between the locking piece 50 and the restraining fingers 61 support 60.The operation to release the locked assembly from its support is also carried out by motorized movement of the arm. 10 robot 1, successively and in the continuity of the translational movement M3 of the third step, the tool 20 being then moved in translation, driven by the arm 10 robot 1, and guided at the same time by the support 60. In this way, the control of the arm's movement alone 10 robot 1 This allows this step to be implemented. The robot then controls the movement of its interface. 10' by a translation along an axis radial to the reference axis A1, of the interface 10' arm 10 robot 1.

[0070] The locking piece 50 is axially mobile along the body 21 between two positions: a distant position in which it is away from the tenons30 and a locking position in which the wedges are 51 are housed at least partially in the notches 40 and lock the tenons into position 30.

[0071] Each of the wedges 51 presents a distal end opposite a proximal end attached to the ring 52, the surfaces supported by the distal ends of each of the wedges 51 being contained within a virtual cylindrical envelope of diameter approximately equal to, or slightly less than, that of the body 21 cylindrical interface 20' of the tool 20. Being slightly lower allows the wedges 51 to penetrate radially slightly into grooves 23 extending parallel to the reference axis A2 to guide the translation of the locking piece 50 in relation to the body 21 of the interface 20' of the tool20.

[0072] The assembly 100 includes at least one means of axial elastic blocking 70 of the locking piece 50 in the locked position configured so that unlocking the locking part 50 The locking position occurs if an axial force greater than a predetermined threshold axial force is applied relative to the assembly formed by the tool. 20 and the arm 10 robot 1 in the relative assembly position and the locking piece 50.

[0073] Similarly, in the distant position, at least one means of axial elastic blocking 70' of the locking piece 50 in a position axially distant from the locking position is configured so that a release of the locking part 50from the distant position occurs if an axial force greater than a predetermined threshold axial force is applied relative to the assembly formed by the tool 20 and the arm 10 robot 1 in the relative assembly position and the locking piece 50.

[0074] In this embodiment, the axial elastic blocking means 70, 70' of the locking piece 50 in the locked position includes at least one ball 73, The ball is held elastically by a spring. 73 is housed in a dedicated opening in the locking piece 50 forming a cage inside which it is mounted freely for rotation and protruding radially with respect to a radial wall of the locking piece 50, here an inner wall radially defining an inner contour of the locking piece 50. One of the wedges 51at least thus presents such an opening inside which the ball 73 is carried. More precisely, each cage houses a ball 73 of the locking piece 50 is supported by a screw 72 configured to screw into a threaded hole 74 extending radially with respect to the reference axis A. The marble 73 is located at an opposite end of the screw 72 relative to a screw head 72. The assembly 100 is equipped here with two balls 73 mounted diametrically opposed to each other. The surface carried by the distal end of the body 21 of the interface 20' of the tool 20 the corresponding one has recesses 71, 71' in which the ball 73 can cooperate at least in part.

[0075] Each marble 73can be elastically constrained radially inside the locking piece 50 so as to come into contact with the surface supported by the body 21 of the interface 20' of the tool 20. When locking piece 50 The ball 73 is moved axially until it is positioned opposite one of the recesses. 71, 71' then the marble 73 is pushed elastically into the associated recess carried by the body 21 of the interface 20' of the tool 20 when it comes into contact with the ball 73.

[0076] The axial elastic locking mechanism 70' of the locking piece 50 in a position axially distant from the locking position is shared with the axial elastic locking means 70 of the locking piece 50 in the locked position, these are distinguished from each other only by their recess.71, 71' the marble 73 and the means to retain it being shared.

[0077] Each marble 73 is associated here with a hollowing out 71 for the locking position and a recess 71' in a position axially distant from the locking position, being situated together on the same path extending along an axis parallel to the reference axis A.

[0078] In another particular embodiment not illustrated, the ball 73 corresponding can be worn by the body 21 of the interface 20' of the tool 20 and the corresponding recesses 71, 71' can be carried by the locking piece 50.

[0079] Alternatively or in addition, the means of axial elastic blocking 70, 70' of the locking piece 50These mechanisms can involve the use of an elastically deformable pin within a recess. The use of such an elastically deformable material, such as plastic, simplifies the locking mechanisms.

[0080] It should be noted that the fixing method requires coaxiality of the reference axis. A1 of the interface 10' arm 10 robot 1 with the reference axis A2 of the interface 20' the tool 20. To help the arm 10 robot 1 particularly during the transition from the relative fixed position to the relative assembled position, the body 21 of the interface 20' of the tool 20 features a hollow interior space 22 of a generally frustoconical shape with a reference axis A2 within which a male part can come to cooperate axially 12 overall frustoconical with a reference axis A1. The notches40 are arranged to surround the male part 12, the hooks 45 being open towards the male part 12. In this way, the male part 12 comes to cooperate progressively during the transition from the relative fixed position to the relative assembled position and allows self-centering of the male part 12 of the interface 10' arm 10 robot 1 in the hollow interior space 22 of the interface 20' of the tool 20 as the movement progresses M1 towards the relative assembly position. These characteristics are particularly visible in section figures 12 and 14.

[0081] Disassembling the interface 20' of the tool 20 compared to the interface 10' arm 10 robot 1follows the same steps in reverse order as the fastening process. In other words, the tool disassembly process 20 arm 10 robot 1, including: a positioning operation in the support 60 of the locked assembly formed by the arm 10 robot 1 and the tool 20 in the assembled position, and the locking piece 50 in the locked position by translation of the arm 10 robot 1 compared to the support 60 in the direction M4' perpendicular to the reference axis, then unlocking in the relative assembly position by relative translational movement M3' parallel to the reference axis A1 arm 10 robot 1, between the set formed by the tool 20 and the arm 10 robot 1in the relative assembly position and at least one locking piece 50 so that wedges 51 attached to the locking piece 50 move away into the notches 40 at least until they are dislodged and thus unlock the tenons in position 30, then a transition from the relative assembly position to a relative fixed position by relative rotational movement M2' between the tool 20 and the arm 10 robot 1 around the axis of rotation so that each of the tenons 30 come to dislodge itself from the circumferential extension 41 of the notch 40 associated, then a transition from a relative fixed position to a relative detached position by relative translational movement M1' between the tool 20 and the arm 10 robot 1 parallel to a reference axis A1 arm10 robot 1 in order to extract the tenons 30 notches 40 associated.

[0082] In the same way as for the fastening process, each step of the dismantling process is carried out by motorized movement of the arm. 10 robot 1. the tool 20 being held in a support 60 after the positioning operation in the support 60 of the locked assembly.

[0083] Attaching the tool, as well as removing it from the tool 20, are implemented through a simple series of steps controlled directly by the robot 1 making operations autonomous, the tool 20 always following the trajectory followed by the robot 1.

[0084] With such a solution, a connection is achieved between an interface 20' of a tool 20 and an interface 10' arm 10 robot1 It is particularly simple in both its structure and construction, as well as in its use and the implementation of an associated fixing and dismantling process. Furthermore, this fixing is ensured by the simple controlled movement of the arm. 10 robot 1 without requiring any external energy source or relying on other means such as cables. Its implementation is therefore both simple and quick.

[0085] Furthermore, the use of the tool 20 by the arm 10 robot 1 is particularly safe and secure thanks in particular to the locking of the assembled position or the relative assembly position.

[0086] Each of the interfaces 10', 20' arm 10 robot 1 and the tool 20,respectively, can be manufactured using an additive manufacturing process, also known as "3D printing". For this, interfaces are preferably chosen. 10', 20' that can be reported on their associated whole, whether it be the arm 10 robot 1 or the tool 20, and each one made from a single piece.

[0087] Naturally, the invention described above is by way of example. It is understood that a person skilled in the art is able to carry out various embodiments of the invention within the scope of the claims.

[0088] For example, the tenons 30 and the notches 40 can be on either interface 10', 20'. Assembly 100 can also be configured so that each of the interfaces 10', 20' includes both tenons 30 notches 40.

[0089] The shape of the notches can also vary without changing their function.

[0090] The assembly can also be modified so that the radial orientations of the tenons 30 and notches 40 or reversed. For example, the notches can be open outwards, that is, in the direction of a move away from the reference axis A and the tenons protruding inwards, that is to say in the direction of a move towards the reference axis A.

[0091] It is emphasized that all features, as they are apparent to a person skilled in the art from this description, the drawings and the attached claims, even if in practice they have only been described in relation to other specific features, both individually and in any combinations, may be combined with other features or groups of features disclosed herein, provided that this has not been expressly excluded or that technical circumstances render such combinations impossible or meaningless.

Claims

1. A method for attaching a tool (20) to an arm (10) of a robot (1), the method comprising at least the following steps: - transitioning from a relative approach position to a relative embedding position by relative translational movement (M1) between the tool (20) and the arm (10) of the robot (1) parallel to a reference axis (A1) of the arm (10) of the robot (1), so that the reference axis (A1) of the arm (10) of the robot (1) is coaxial with a reference axis (A2) of the tool (20), and so as to cause tenons (30) to penetrate associated notches (40), each of the notches (40) being associated with one subunit from the tool (20) and the arm (10) of the robot (1), and with one of the tenons (30) rigidly connected to the other subunit from the tool (20) and the arm (10) of the robot (1), then - transitioning from the relative embedding position to a relative assembly position by relative rotational movement (M2) between the tool (20) and the arm (10) of the robot (1) about the axis of rotation, in such a way that each of the tenons (30) is housed in a circumferential extension (41) of the associated notch (40) and is axially retained therein, then - locking in the relative assembly position by relative translational movement (M3) parallel to the reference axis (A1) of the arm (10) of the robot (1), between the unit formed by the tool (20) and the arm (10) of the robot (1) in the relative assembly position and at least one locking part (50), the method being characterized in that wedges (51) rigidly connected to the locking part (50) penetrate the notches (40) and lock the tenons (30) in position in the locking position.

2. The attachment method according to claim 1, characterized in that during the transition from the relative embedding position to the relative assembly position, each of the tenons (30) is housed snugly in a circumferential extension (41) of the associated notch (40).

3. The attachment method according to claim 1 or 2, characterized in that the transition from the relative approach position to the relative embedding position is effected by motorized movement of the arm (10) of the robot (1), the tool (20) being retained in a support (60).

4. The attachment method according to any of the preceding claims, characterized in that the transition from the relative embedding position to the relative assembly position is effected by motorized movement of the arm (10) of the robot (1), the tool (20) being retained in the support (60).

5. The attachment method according to any of the preceding claims, characterized in that the locking in the relative assembly position is effected by motorized movement of the arm (10) of the robot (1), the locking part (50) being retained in the support (60).

6. The attachment method according to the preceding claim, characterized in that it comprises an operation of releasing the locked unit constituted by the arm (10) of the robot (1) and the tool (20) in the assembly position, and the locking part (50) in the locking position by translation of the arm (10) of the robot (1) in relation to the support (60) in a direction (M4) perpendicular to the reference axis.

7. The attachment method according to any of the preceding claims, characterized in that the locking part (50) comprises a ring (52).

8. The attachment method according to any of the preceding claims, characterized in that the support (60) is in the form of a fork provided with two retaining fingers (61).

9. The attachment method according to any of the preceding claims, characterized in that the tenons (30) are all rigidly connected to the same subunit from the arm (10) of the robot (1) and the tool (20).

10. The attachment method according to any of the preceding claims, characterized in that the tenons (30) are equally distributed.

11. The attachment method according to any of claims 1 to 9, characterized in that the tenons (30) are not equally distributed.

12. An assembly (100) of a tool (20) to an arm (10) of a robot (1), the arm (10) of the robot (1) and the tool (20) being movable between: - a relative approach position and a relative embedding position by relative translational movement (M1) between the tool (20) and the arm (10) of the robot (1) parallel to a reference axis (A1) of the arm (10) of the robot (1) so that, in the relative embedding position, the reference axis (A1) of the arm (10) of the robot (1) is coaxial with a reference axis (A2) of the tool, and tenons (30) penetrate associated notches (30), each of the notches (30) being associated with a subunit from the tool (20) and the arm (10) of the robot (1) and with one of the tenons (30) rigidly connected to the other subunit from the tool (20) and the arm (10) of the robot (1), - the relative embedding position and a relative assembly position by relative rotational movement (M2) between the tool (20) and the arm (10) of the robot (1) about the axis of rotation in such a way that, in the relative assembly position, each of the tenons (30) is housed in a circumferential extension (41) of the associated notch (40) in relation to the relative embedding position and is axially retained therein, the assembly (100) further comprising at least one locking part (50) configured to ensure locking in the relative assembly position by relative translational movement (M3) parallel to the reference axis (A1) of the arm (10) of the robot (1), between the unit formed by the tool (20) and the arm (10) of the robot (1) in the relative assembly position and the locking part (50), characterized in that, in a locking position, wedges (51) rigidly connected to the locking part (50) penetrate the notches (40) and lock the tenons (30) in position.

13. The assembly (100) according to claim 12, characterized in that at least some of the tenons (30) and / or notches (40) have an inclined wall (31) having at least one axial component so as to allow adjustment of the tenons (30) housed in a circumferential extension (41) of the associated notch (40) during the transition from the relative embedding position to the relative assembly position.

14. The assembly (100) according to claim 12 or 13, characterized in that the tenons (30) are all rigidly connected to the same subunit from the arm (10) of the robot (1) and the tool (20), preferably to the arm (10) of the robot (1), and the notches (40) are all rigidly connected to the same other sub-subunit from the arm (10) of the robot (1) and the tool (20), preferably to the tool (20).

15. The assembly (100) according to claim 14, characterized in that the locking part (50) is rigidly mounted in a sliding connection with one of the subunits from the arm (10) of the robot (1) and the tool (20), preferably with the subunit to which the tenons (30) are rigidly connected.

16. The assembly (100) according to any of claims 12 to 15, characterized in that the locking part (50) comprises a ring (52), the wedges (51) preferably projecting radially in relation to a reference axis (A5) of the locking part (50).

17. The assembly (100) according to any of claims 12 to 16, dependent at least on claim 15, characterized in that it comprises at least one axial elastic blocking means (70) of the locking part (50) in the locking position, configured so that an unblocking of the locking part (50) from the locking position occurs if an axial force greater than a predetermined threshold axial force is applied relatively between the unit formed by the tool (20) and the arm (10) of the robot (1) in the relative assembly position and the locking part (50).

18. The assembly (100) according to the preceding claim, characterized in that the axial elastic blocking means (70) of the locking part (50) in the locking position comprises at least one ball (71) elastically stressed by a spring.