FR2676955A1 - Cartesian handling robot incorporating belt-driven transmission means - Google Patents

Abstract

The invention is of the field of handling devices and its subject is a handler, of the "cartesian robot" type. This handler, of the sort of those comprising fixed elements (8) supporting at least one mobile assembly (1, 2), itself supporting a doing member (30, 31), the mobile assembly (1, 2) comprising a plurality of carriages (3, 23 and 4, 22) in stages, each carriage, on the one hand, supporting a guide path (20, 21) for the displacement of the carriage succeeding it and, on the other hand, being connected to a driving member (12, 13, 14, 15) by transmission means, is mainly characterised in that the transmission means are belts (10, 11 and 26, 27) in a closed loop, each of the ends of the guide paths (20, 21) including return pulleys (16, 17 and 28, 29) and the driving members being drive wheels (12, 13 and 24, 25) supported by the said fixed elements (8).

Description

 The invention is in the field of handling devices, called manipulators with programmed control, and more particularly relates to a manipulator of the so-called "Cartesian robot" type capable of moving one or more effector organs in at least two directions in space .

 It will be recalled that the Cartesian robots are in particular intended for automated handling for applications such as palletizing, storage, and the feeding or unloading of machines.

These robots mainly consist of a set of fixed elements forming a framework and supporting mobile assemblies and sub-assemblies, the mobile sub-assemblies moving relative to the mobile assemblies, which themselves move relative to the frame.

 Each of the movements of the mobile assemblies and sub-assemblies are generated by motor members which can be controlled by means of automation or programming. One of these motor members is generally located on the frame and generates the movement of a mobile assembly, said mobile assembly supporting at least one motor member generating the movement of a mobile sub-assembly. The displacements of the moving assemblies and sub-assemblies are generally rectilinear along axes perpendicular to each other.

 To know the technological environment of the present invention, reference may be made to the manipulators described by the patent publications FR2639572 (RENAULT and EVOLUTECH) and FR2606313 (THIERON SA).

 The performance of these robots is directly linked to their dynamic capacities, that is to say to the speeds and accelerations of the moving elements, which they can develop. These capacities are limited by the inertia of the masses of the mobile elements.

 The aim of the present invention is to provide a Cartesian robot with increased dynamic capacities, said robot being able to work not only for routine operations such as palletizing or storage, but also in hostile environments, and / or at high speed and / or for operations requiring great flexibility or a double operation, such as nailing or welding.

 According to the invention, a Cartesian robot, of the type of manipulator robots equipped with programming means and / or automation means, comprising fixed elements forming a framework supporting at least one mobile assembly itself supporting a mobile effector member, said movable assembly comprising a plurality of trolleys in stages supporting each other successively up to the last trolley, said end, which supports said effector member, each of the trolleys, on the one hand supporting a path for guiding the movement of another trolley succeeding it, and on the other hand being connected to a drive member by transmission means, the first carriage moving along an axis X along a first guide path, the latter being able to be supported by one of said elements fixed forming the framework, the drive members being located at a so-called first end of the first guide path and implemented by means of coordinati movements that they generate, the transmission means connected to each of said successive carriages, on the one hand each extending over at least the cumulative length of the guide path of the carriage to which they are connected and the guide paths of carriages preceding it, and on the other hand comprising means for returning the movement generated by the motor member to which they are connected, from the axis X of movement of the first carriage and successively along the axes of movement of the carriages preceding that to which they are connected, is mainly characterized in that the transmission means are loop belts assigned to and engaged each on a carriage, the return means being return pulleys located at each end of the guide tracks, and the members motors being drive wheels. I1 results from these provisions on the one hand that the dynamic capacities of the robot are increased by the fact that the masses in movement are reduced, and on the other hand that the robot can work in hostile medium by the fact that motors generating the movement drive wheels can be moved away from the efective organs.

 Said coordination means advantageously comprise at least one controllable differential inducing the displacement on the one hand in the same mobile assembly, of any one of the carriages along its axis as a function of the movement of another any carriage along its axis, and on the other hand of at least one movable assembly, the means for controlling the differential at least being a means of the group of means comprising the hydraulic means, the electrical means, and the mechanical means incorporating a clutch and a brake, so that the differential at least coordinates, as a function of the position assigned to the effector members, the displacements of the successive movable carriages between them and the displacements of the movable assembly at least.

 As a result, the robot has great flexibility in maneuvering, on the one hand that the transmission means are belts and on the other hand the possibility of managing the movement of the effector members by controlled combinations of the implementation. of these.

 According to a preferred embodiment, said first carriage supports at least one, said second, guide path of at least one second carriage guided in displacement along a Z axis converging with the X axis and connected to a second driving wheel by second belts.

 According to a first embodiment, the robot comprises at least two mobile assemblies each supporting an effector member, so that the two effector members can together form a clamp by the combined movement of the two mobile assemblies.

 According to a second embodiment, the robot comprises at least two so-called second carriages, each supporting a similar effector member, such as a plate, the two said second carriages moving along the first path along two parallel axes Z and Z ′, so that two effector members together form a clamp by the combined movement of the two second carriages each supporting one of them.

 It follows from said first and second embodiments, not only that the robot integrates a gripper function with a large opening capacity, the tightening of which can be symmetrical or not, but also that the robot can constitute a support for a plurality of tools for carrying out successive operations.

 According to an advantageous embodiment, the robot comprises at least two so-called second carriages each moving along a guide path along two converging axes Z and Y.

 According to another advantageous embodiment, at least the second carriage supports a so-called third guide path along which moves, along a Y axis converging with said Z axis, two so-called third carriages connected to a third drive wheel generating their displacements by third transmission means, the third transmission means from the Z axis to the Y axis being formed by a ball screw operated from the X axis by means of third belts, the two third carriages being assembled with said ball screws for their displacement each along one of its ends; where it follows that the effector members supported by each of the two said third carriages together form a clamp, the two said third carriages moving simultaneously to get closer or move away.

 Advantageously, the belts are toothed belts and, preferably, equipped with preload tensioners.

 The frame is preferably a frame from the group of those comprising the brackets, these being able to be articulated, the gantries comprising two posts, the gantries comprising four posts in order to allow the robot to cover a large work surface.

 The guide means are advantageously means of the group of those implementing the ball recirculation devices and the roller devices traveling along rails, from which it follows that the robot can move precisely and at a speed important.

 Each of the mobile elements is preferably equipped with a stroke limiting device and shock absorbers for an industrial approach to the use of the robot.

The present invention will be better understood and details will be apparent from the description which will be given of a preferred embodiment, in relation to the figures of the appended plates, in which
FIG. 1 is a partial schematic representation of a robot according to a first embodiment of the invention,
FIG. 2 is a diagram showing the means of motorization and coordination implemented in the robot of FIG. 1,
FIGS. 3 and 4 respectively illustrate a second example of embodiment of a robot, and the connections between its motor members,
FIGS. 5 and 6 respectively illustrate a third example of embodiment of a robot, and the connections between its motor members,
- Fig.7 to 10 are each a schematic representation of other embodiments of a robot according to the invention corresponding to different applications.

 In fig.l, a robot according to the invention comprises two mobile assemblies 1 and 2. The base of each of them is formed by two first carriages 3 and 4 traveling along a first guide path 6 which is supported by a fixed element 8 forming the framework of the robot. First belts 10 and 11 connect each of the first carriages 3 and 4 to first drive wheels 12 and 13 located at one end 14, called the first end, of the first guide path 6. The first belts 10 and 12 in a loop are affected and each engaged on a carriage 3 and 4 and each extend along the length of the first guide path 6. These belts 3 and 4 are oriented along an axis X of movement of the first carriages by first pulleys of returns 16 and 17 located opposite the first drive wheels 12 and 13 at the other end 18 of the first guide path 6.

 Each of the mobile assemblies 1 and 2 supports a second guide path 20 and 21 along which a second carriage 22 and 23 flows. Each of these second carriages is connected to a second drive wheel 24 and 25 located at the end 14 known as the first , from the first guide path by second loop belts 26 and 27 which extend over the cumulative lengths of the first guide path 6 and the second guide path 20 or 21. These belts 26 and 27 are oriented from the axis X towards an axis Z of movement of the second carriage 22 or 23 by second return pulleys 28 and 29 situated at each of the ends of each of the guide tracks 6 and 20 or 21.

 Each of the second carriages 22 and 23 supports an effector member 30 and 31. By the combined movement of the first carriages 3 and 4, the effector members 30 and 31 together form a clamp 32.

 In FIG. 2, the driving wheels 12, 13, 24 and 25 are interconnected by differentials 34, 35, 36 which can be controlled in order to coordinate the movements, on the one hand of the second carriages 22 and 23 between them, and on the other hand, the first carriages 3 and 4 with the second carriages 22 and 23.

 It will be recalled that differentials, such as 34,35,36 essentially comprise an input shaft, an output shaft and a rotary cage arranged in a known manner.

 The simultaneous and identical movements of the first carriages 3 and 4, the second carriages 22 and 23 being stationary relative to the first carriages 3 and 4, are generated by the first drive wheels 12 and 13 by means of a first motor 38. This motor 38 drives the drive wheel 12, said first, of one of the first carriages 4. This drive wheel 12 is mounted on the input shaft of a first differential 34, and the drive wheel 13 said second, of the another first carriage 3 is mounted on the output shaft of this same differential 34.

 The opening or closing of the clamp 32 is obtained, on the one hand by a differentiated and coordinated movement of each of the first carriages 3 and 4 and on the other hand by a control of the immobility of the second carriages 22 and 23 by compared to the first carriages 3 and 4.

 The differentiated and coordinated movement of each of the first carriages 3 and 4 is obtained by the implementation of a second motor 40 which rotates the rotary cage of the first differential 34. The immobility of the second carriages 22 and 23 is obtained at by means of a set of two differentials 35 and 36.

The input shaft of one of these 35, called the second, is connected to the first driving wheel 12; the driving wheel 24 said third, driving a first second carriage 4 is mounted on the output shaft of said second differential 35. The input shaft of the other differential 36, said third, of said set of differential is connected to the second drive wheel 13; the driving wheel 25, called the fourth, for driving the second of the said second carriages 23, is mounted on the output shaft of the third differential 36.

 The simultaneous and identical movements of the first 22 and second 23 second carriages, the first carriages 3 and 4 being stationary, are generated by said third 24 and fourth 25 drive wheels by means of a third motor 42 which drives each of the rotary cages of the second 35 and third 36 differentials.

 In fig.3, the first carriage 4 supports a second guide path 22 along which circulates two said second carriages 44 and 45 each supporting an effector 46 and 47. The combined movement of one of the second carriages 46 along a axis Z, and on the other 47 of the second carriages along an axis Z ′ parallel to the axis Z gives the effector members 46 and 47 a gripper function 48.

 In FIG. 4, the driving wheel 12, called the first one, of the first carriage 4 is driven in rotation by a first motor 30.

 The output shaft of a differential 50, said first, is connected to the drive wheel 24 of one 44, said first, of said second carriages; the output shaft of a second differential 52 is connected to the other, said second 45 of said second carriages; the output shaft of the first differential 50 is connected to the input shaft of the second differential 52. A second motor 54 rotates the rotary cage of the two differentials 50 and 52. A connection device 56 comprising a clutch and a brake, is placed in the connection zone between the so-called second motor 54 and the rotary cage of the second differential 52.

 The displacements of the first carriage 4 are obtained by using the first motor 38 and the brake of the connection device 56, said brake ensuring the immobility of the second carriages 44 and 45 relative to the first carriage 4.

 The opening or closing of the clamp 48 is obtained by using the second motor 54 and the clutch of the connecting device 56.

 In fig.5, the second carriage 44 supports a third guide path 60 along which move, along an axis Y, two carriages 58 and 59 said third connected to a third drive wheel 61 by means of third transmission means.

 The third transmission means are composed, on the one hand of a belt 63 extending over the cumulative lengths of the first 6 and second 22 guide paths, and on the other hand of a ball screw 64 extending along the length of the third guide path 60. The third carriages 58 and 59 each support an effector 46 and 47 and are assembled with the ball screw 64 to move each along one of its ends .

 In FIG. 6, the mounting of the motorization and movement coordination means is identical to that described in FIG. 4.

 The displacements of the first carriage 4 are obtained by the use of the first motor 38 and the brake of the connection device 56.

 The displacements of the second carriage 44 are obtained by the use of the second motor 54 and of the clutch of the connection device 56.

 The opening and closing of the clamp 48 are obtained by the use of the second motor 54 and the brake of the connection device 56.

 The device 56 is called a "link" because of the fact that it controls the relationship between the output shaft of the motor 54 and the differential 52.

 In Fig.7, the frame is a gantry comprising two posts 66 and 67 and the effector 46,47 are tools, such as nailers.

 In fig.8, the frame is a bracket 68 which can be articulated along an axis G of rotation.

 In fig. 9, the robot comprises a plurality of first carriages, each comprising a conveyor belt driven by a belt 26, the carriages remaining equidistant from each other but able to be moved together by a belt 11.

 In Fig. 10, the framework is a portico comprising four posts 70,71,72,73.

 On fig.7 to 10, we have designated by the same references as in fig.l the bodies performing similar functions; in these figures, programming means 74 manage the implementations of the different motors and, consequently, the movements of the different carriages.

 Although a preferred embodiment has been described and shown, it should be understood that the scope of the present invention is not limited to this form but that it extends to any device comprising the characteristics set out above. .

Claims (2)

1.- Cartesian robot, of the kind of robot manipulator equi  of programming means (74) and / or means  automation, comprising fixed elements forming  a frame supporting at least one mobile assembly  (1 and 2) itself supporting an effector member (30  and 31) mobile, said mobile assembly (1 and 2) comprising  a plurality of carriages (3.23 and 4.22) on the floor are  supporting successively until the last carriage,  said end, which supports said effector member  (30 and 31) each of the carriages, on the one hand supporting  a guide path (20,21) of the displacement of another  trolley succeeding it, and on the other hand being connected  to a drive member (12,13,24,25) by means of  transmission, the first carriage moving next  an X axis along a first guide path (6),  it can be supported by one of said elements  fixed (8) forming the framework, the driving members (12,  13,24,25) being located at a so-called first end  (14) of the first guide path (6) and implemented  by means of movement coordination  that they generate, the means of transmission linked  to each of said successive carriages, on the one hand  each stretching over at least the cumulative lengths  the guide path of the carriages preceding it, and  on the other hand comprising return means (16,17,  28,29) of the movement generated by the motor member to which  they are connected, from the X axis of displacement of the pre  mier carriage (4,3) and successively along the axes  of movement of the carriages preceding that at which  they are connected, towards the axis of movement of the carriage  to which they are connected, characterized  in that the means of trans  mission are belts (10,11 and 26,27) loop  assigned to and engaged each on, a cart, (4.3  and 22,23),  in that the referral means  are pulleys (16,17 and 28,29) located at each  the ends of the guide tracks (6 and 20,21),  and  in that the driving organs  are driving wheels (12,13 and 24,25) 2.- Robot according to claim 2 characterized  in that the belts (10,11)  and (26,27) are moved by said means  which include at least one differential  (34,35,36) controllable inducing displacement,  - in the same mobile unit  (1,2) of any of the carriages (3,4 and 22,23)  along its axis as a function of the displacement of a  any other carriage along its axis,  - a mobile assembly (1,2  at least,  so that the differen  tiel at least coordinates according to the position  assigned to the effector organs, the displacements of  successive mobile carts between them, and moves them  the mobile assembly at least 3. Robot according to claim 2 characterized  in that the steering means  differential at least (34,35,36) is a means of  group of means including hydraulic means,  the electrical means (38, 40, 42 and 54) and the means  mechanical (56) incorporating a clutch and a brake 4. Robot according to claim 1 characterized  in that said first carriage  (3 and 4) supports at least one guide path, (21  and 20), said second, of at least one second carriage  (22 and 23) guided in movement along a converging Z axis  gent with the X axis and connected to a second drive wheel  (24 and 25) by second belts 5.- Robot according to claim 1 characterized  in that it includes at least  two mobile assemblies (1 and 2) each supporting one  effector organ (30,31)  so that both  effectors can together form a forceps  (32) by the combined displacement of the two sets  6.- robot according to claim (4) characterized  in that it includes at least  two so-called second carriages (44,45) each supporting  a similar effector member (46,47), such as a plate,  the two so-called second carts moving along  of the second path (22) along two axes Z and Z 'paral  the the,  so that two organs  effectors together form a clamp by displacement  first two carriages supporting each  one two 7.- robot according to claim 4 characterized  - in that it includes at least  two so-called second carts each moving the  along a guide path along two axes Z and  Converging Y 8. Robot according to claim 1 characterized  in that the second carriage  at least (44) supports a guide path (60) said  third along which moves along an axis  Y 'converge with said axis Z, two carriages (58,59)  so-called thirds connected to a third driving wheel  (61) generating their displacements by thirds  means of transmission,  in that the third means  transmission from the Z axis to the Y 'axis are formed  a ball screw (64) operated from the X axis to  by means of third belts (63),  in that the two thirds  carriages (58 and 59) assemble with said screw  ball (64) in order to circulate each along one  ends of it,  so that the organs  effectors (46, 47) supported by each of the two so-called  third carriages (58, 59) together form a clamp,  (48) the two so-called third carriages moving  simultaneously to approach or move away 9.- Robot according to claim 1 characterized  in that the belts  (10,11,16,27 and 63) are toothed belts and equi  preload tensioner blocks 10.- Robot according to claim 1 characterized  in that the framework is a  framework of the group of those including the gallows  (68), which can be articulated (6), the por  ticks comprising two poles (66,67), porticoes  comprising four posts (70 to 73) 11.- Robot according to claim 1 characterized  in that the guide means  are group means of those implementing  ball recirculation devices and their availability  pebbles running along rails. 12.- Robot according to claim 1 characterized  in that each of the elements  mobile is equipped with a stroke limiting device  and shock absorbers.