Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
  • B23Q1/00—Members which are comprised in the general build-up of a form of machine, particularly relatively large fixed members
  • B23Q1/25—Movable or adjustable work or tool supports
  • B23Q1/44—Movable or adjustable work or tool supports using particular mechanisms
  • B23Q1/48—Movable or adjustable work or tool supports using particular mechanisms with sliding pairs and rotating pairs
  • B23Q1/4876—Movable or adjustable work or tool supports using particular mechanisms with sliding pairs and rotating pairs a single sliding pair followed parallelly by a single rotating pair
  • B23Q1/4885—Movable or adjustable work or tool supports using particular mechanisms with sliding pairs and rotating pairs a single sliding pair followed parallelly by a single rotating pair followed parallelly by a single rotating pair
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
  • B23Q1/00—Members which are comprised in the general build-up of a form of machine, particularly relatively large fixed members
  • B23Q1/25—Movable or adjustable work or tool supports
  • B23Q1/44—Movable or adjustable work or tool supports using particular mechanisms
  • B23Q1/50—Movable or adjustable work or tool supports using particular mechanisms with rotating pairs only, the rotating pairs being the first two elements of the mechanism
  • B23Q1/54—Movable or adjustable work or tool supports using particular mechanisms with rotating pairs only, the rotating pairs being the first two elements of the mechanism two rotating pairs only
  • B23Q1/5406—Movable or adjustable work or tool supports using particular mechanisms with rotating pairs only, the rotating pairs being the first two elements of the mechanism two rotating pairs only a single rotating pair followed perpendicularly by a single rotating pair
  • B23Q1/5412—Movable or adjustable work or tool supports using particular mechanisms with rotating pairs only, the rotating pairs being the first two elements of the mechanism two rotating pairs only a single rotating pair followed perpendicularly by a single rotating pair followed perpendicularly by a single rotating pair
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
  • B23Q1/00—Members which are comprised in the general build-up of a form of machine, particularly relatively large fixed members
  • B23Q1/25—Movable or adjustable work or tool supports
  • B23Q1/44—Movable or adjustable work or tool supports using particular mechanisms
  • B23Q1/50—Movable or adjustable work or tool supports using particular mechanisms with rotating pairs only, the rotating pairs being the first two elements of the mechanism
  • B23Q1/54—Movable or adjustable work or tool supports using particular mechanisms with rotating pairs only, the rotating pairs being the first two elements of the mechanism two rotating pairs only
  • B23Q1/5468—Movable or adjustable work or tool supports using particular mechanisms with rotating pairs only, the rotating pairs being the first two elements of the mechanism two rotating pairs only a single rotating pair followed parallelly by a single rotating pair
  • B23Q1/5475—Movable or adjustable work or tool supports using particular mechanisms with rotating pairs only, the rotating pairs being the first two elements of the mechanism two rotating pairs only a single rotating pair followed parallelly by a single rotating pair followed perpendicularly by a single rotating pair
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
  • B23Q5/00—Driving or feeding mechanisms; Control arrangements therefor
  • B23Q5/02—Driving main working members
  • B23Q5/04—Driving main working members rotary shafts, e.g. working-spindles
  • B23Q5/10—Driving main working members rotary shafts, e.g. working-spindles driven essentially by electrical means
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
  • B23Q5/00—Driving or feeding mechanisms; Control arrangements therefor
  • B23Q5/02—Driving main working members
  • B23Q5/04—Driving main working members rotary shafts, e.g. working-spindles
  • B23Q5/20—Adjusting or stopping working-spindles in a predetermined position
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
  • B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
  • B25J11/00—Manipulators not otherwise provided for
  • B25J11/005—Manipulators for mechanical processing tasks
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
  • B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
  • B25J13/00—Controls for manipulators
  • B25J13/08—Controls for manipulators by means of sensing devices, e.g. viewing or touching devices
  • B25J13/088—Controls for manipulators by means of sensing devices, e.g. viewing or touching devices with position, velocity or acceleration sensors
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
  • B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
  • B25J19/00—Accessories fitted to manipulators, e.g. for monitoring, for viewing; Safety devices combined with or specially adapted for use in connection with manipulators
  • B25J19/0025—Means for supplying energy to the end effector
  • B25J19/0029—Means for supplying energy to the end effector arranged within the different robot elements
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
  • B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
  • B25J5/00—Manipulators mounted on wheels or on carriages
  • B25J5/02—Manipulators mounted on wheels or on carriages travelling along a guideway
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
  • B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
  • B25J9/00—Program-controlled manipulators
  • B25J9/02—Program-controlled manipulators characterised by movement of the arms, e.g. cartesian coordinate type
  • B25J9/04—Program-controlled manipulators characterised by movement of the arms, e.g. cartesian coordinate type by rotating at least one arm, excluding the head movement itself, e.g. cylindrical coordinate type or polar coordinate type
  • B25J9/046—Revolute coordinate type

Definitions

• the present invention relates to the field of machine tools, particularly machining ones, and more particularly to adaptations of the kinematic structures of machine tools implemented for operations requiring great rigidity.
• articulated arms that are very well known in the field of robotics.
• document CN110802465 proposes automatic deburring equipment with seven axes of movement whose rigidity and precision performances do not allow machining operations of prismatic parts to be considered within the tolerances and qualities required by these parts.
• This machine tool architecture is particularly advantageous in that it offers an articulated structure with two arms to implement the movements of the electro-spindle according to the plane perpendicular to the axis of rotation of the electro-spindle.
• An articulated structure formed by two pivoting arms is simpler and less expensive to implement than conventional stacked structures.
• This plunging movement is implemented either by a movement module associated with the part-carrying module, and then the plate is fixed in translation, or by a movement module associated with the plate and then the part is fixed in translation during machining.
• the invention thus constituted the result not only of a reduction in the number of axes of movement of multi-axis articulated structures of the robot type but also of a selection and distribution between positioning axes implemented by the articulated structure and a working axis implemented by the translational movement.
• the proposed kinematic structure therefore did not present any redundant movements.
• an articulated structure also made it possible to enlarge the window in which machining can be carried out.
• an articulated structure can carry out movements outside said window and makes a plurality of operations easier such as:
• Another document EP3310528 describes a machine tool for machining a part, comprising a spindle arm having a spindle for receiving a tool or the workpiece, the spindle arm being movably fixed to an arm receiving part of the workpiece.
• the spindle arm comprises; a first spindle arm section, which is designed as a longitudinal member and can be rotated around a first axis of rotation relative to the spindle arm receiving section and is hinged to the spindle arm receiving section ; a second spindle arm section, designed as a longitudinal member and rotatable relative to the first spindle arm section around a second axis of rotation, which is connected to the first spindle arm section;
• the spindle arm receiving section comprising: a first subsection and a second subsection spaced on the machine frame to receive the spindle arm, the first subsection of the spindle arm receiving section having a first drive biased to transmit a first torque to the first spindle arm section;
• the first spindle arm section includes: a first subsection and a second subsection spaced over the spindle arm receiving section for receiving the second spindle arm section, the first subsection of the first spindle arm section having a second drive for transmitting a second torque to the
• the machine tool includes a machine frame, a clamping section provided on the machine frame for clamping a workpiece on the machine tool, a swing arm receiving section provided on the machine frame, a first swing arm pivotally mounted on the receiving section so as to be pivotable about a first axis of rotation, a second pivot arm pivotally mounted about a second axis of rotation, a spindle support arm mounted on the second pivot arm so that it can rotate around a third axis of rotation, a milling head mounted on the spindle support arm so that it can rotate around a fourth axis of rotation, and a working spindle held on the milling head for receiving a tool, the third axis of rotation being oriented perpendicular or transverse to the fourth axis of rotation, [0033] Although less limited in its movement possibilities, it appears that the arrangement of the different subass
• the applicant has carried out research aimed at proposing a machine tool, in particular a machining tool with an articulated arm presenting optimized characteristics.
• the machine tool of the invention comprises a frame and at least one module for positioning a rotating work spindle, said positioning module ensuring the movement of the rotating work spindle relative to the fixed frame in implementing the following connections;
• the rotating work spindle ensuring the rotational movement of a tool along a sixth axis perpendicular to the fifth axis.
• This machine tool is remarkable in that the pivot connections on the second axis, the third axis and the fifth axis are implemented by two bearings each: a main bearing and a secondary recovery bearing distant from one of the other,
• the fourth axis of the third pivot link is positioned in a median plane defined between the two bearings guiding the rotation of the pivot link along the third axis
• pivot connections each being the subject of a motorization integrating a geared motor composed of a motor and a reduction gear
• the machine tool being controlled by a control unit associated, for each axis of the pivot links, with a variator for processing control loops operating in a closed loop,
• each axis of the pivot connections comprising two measuring systems with a first encoder arranged before the gearbox ensuring speed measurement for speed regulation purposes and a second encoder arranged after the gearbox ensuring position measurement for the closed loop of position control,
• the different subassemblies are dimensioned to achieve a static stiffness greater than 10 N/ ⁇ m (static holding stiffness between the rotating work spindle and the frame).
• the static stiffness of a robot including articulated serial kinematics is less than 1 N/ ⁇ m.
• [0061] provide a dynamic transmission between the motor and the moving parts on the second and third axes such that position regulation can be ensured with a position feedback measured by a second encoder, directly and only on the moving part after the gearbox, by providing a margin of stability which allows a sufficiently high position gain to achieve optimum trajectory tracking.
• Such a machine tool design also makes it possible to achieve a high jerk (derived from the acceleration vector with respect to time - i.e. the third derivative with respect to the time of the position vector) on the positioning trajectory, namely 100 m /s 3 .
• the integration of the second encoder into the positioning loop, associated with a high jerk, is made possible by the high stiffness obtained by the structure, imperative characteristic to achieve high quality and precision for the operation to be carried out.
• the significant kinematic stiffness makes it possible to position the encoder of the position control loop on the moving part after the reducer.
• the orientation of the arms in the work zone is designed to generate a preload on the gearbox associated with the first pivot connection that is all the stronger, and thus increase its rigidity, as the inertia relative to the axis is significant. This has the effect of maintaining a constant and high ratio between rigidity and inertia, which ensures optimal performance of the position control throughout the entire working area. Indeed, thanks to this rigidity, a sufficiently high natural frequency is obtained on the first pivot link, which allows position regulation on the second encoder and more dynamic behavior.
• the position information from the second encoder returns directly to the variator for regulation purposes (and not to the digital control) in the position control loop.
• the first encoder only measures the speed.
• the machine tool comprises cables and pipes for supplying the necessary energies to the rotating work spindle, the second arm and the wrist being provided with a core hollow to accommodate them.
• the machine tool comprises on the fourth axis and the fifth axis of rotation, means for winding the cables and pipes preventing them from twisting during movements so that they They only work in flexion, thus improving their durability.
• the subassembly called wrist forms an assembly with the rotating work spindle, an assembly which, comprising your motors and your reduction gears associated with the fourth, fifth and sixth axes, comes introduce and fix in the second arm by means of an interface flange so that said assembly can be easily assembled, disassembled and extracted from the rest of the machine reducing the duration of maintenance operations.
• This wrist function also includes the cables and pipes for supplying energy from the cable carrying chain of the carriage movable in translation along the first axis.
• This second arm has a sufficient section to contain the cable winding system and allow the diameter of said cable windings to change.
• the hollow core of the second arm accommodates a winding shaft and a concentric jacket defining a winding volume of a single sheath grouping together cables and pipes, the radius of curvature of the cables and pipes in the winding volume changing according to the angle of rotation of the wrist along the fourth axis.
• the wrist sub-assembly is equipped with two bearings to implement the pivot connection along the fifth axis and between which the rotating working spindle moves in rotation, a first bearing accommodating a gear motor crossed axially by a rotating joint, for supplying hydraulic and pneumatic energy to the rotating work spindle.
• the hydraulic cables used are high pressure cables.
• the second bearing of the wrist sub-assembly guides in rotation a rotating part secured to the rotating work spindle and equipped with a winding device for the necessary cables and pipes for the supply of electrical energy and for lubrication so that the radius of curvature of said cables and pipes varies as a function of the angular position of the rotating work spindle along the fifth axis,
• the first arm comprises between the second axis and the third axis of rotation a concave volume allowing an increased angular travel of the second arm which can be housed in this concavity in the folded position .
• This design provides great compactness to the positioning module in the folded position, thus freeing up the space available for loading/unloading/transferring parts and optimizing the footprint of the machine (reduced floor space).
• said first arm comprises two ends, a first end crossed by the second axis of rotation and a second end crossed by the third axis of rotation, the concave volume starting from the low end and being defined so that in the folded position, this concave volume prevents the rear part of the rotating work spindle from abutting against the first arm.
• the rotating spindle can project backwards relative to the fifth axis of rotation without rotation along this axis being hindered in the folded position.
• the bearings supporting the second axis and the third axis are symmetrical.
• This design allows the gear motors of these axes to be installed either on the right or on the left. It has the advantage of reducing the bulk on one of the side faces of the positioning module. It is thus possible to choose the versions of the positioning modules (reduced space requirement on one or other of the side faces) according to the installation constraints of the machine.
• This advantage is particularly interesting in a machine tool configuration with two work units, sharing the same slide. It allows a minimum distance on the first axis between the two units, thanks to the "external" installation of the gear motors.
• This symmetrical design can also make it possible to integrate a complementary motorization or a balancing system opposite the main motorization of the axis, with the aim of increasing the machining capacities, reducing energy consumption or increase the lifespan of components (such as gearboxes).
• the second arm is preformed so that the fourth axis of rotation intersects perpendicularly with the fifth axis of rotation and does not intersect with the third axis of rotation.
• the size of the positioning module in the folded position is optimized.
• the rigidity of the two arms is improved by avoiding too large a recess in the first arm while retaining a large second arm to integrate the cable winding system.
• said first arm comprises two ends, a first end crossed by the second axis of rotation and a second end crossed by the third axis of rotation, said second end being equipped with two bearings to guide the second arm in rotation along the third axis,
• said second arm comprises two ends, a first end crossed by the third axis of rotation and a second end accommodating the so-called wrist sub-assembly,
• the first end of the second arm being preformed to be accommodated between the two bearings fitted to the second end of the first arm.
• said first arm comprises two ends, a first end crossed by the second axis of rotation and a second end crossed by the third axis of rotation
• said second arm comprises two ends, a first end crossed by the third axis of rotation and a second end accommodating the so-called wrist subassembly
• the first end of the second arm being equipped with two bearings for guiding the second arm in rotation along the third axis, said two bearings being spaced apart so as to come on either side of the second end of the first arm.
• the translation along the first axis is motorized according to one of the following technologies:
• said frame is preformed so as to accommodate two horizontal rails arranged parallel to the first axis of movement in translation and offset in height, said carriage being preformed to cooperate with said rails.
• the translation along the first axis is motorized by means of a linear motor and said frame comprises a vertical flat surface with a longitudinal axis parallel to the rails and intended to accommodate the part secondary of the linear motor, said flat surface being arranged higher than said rails and offset laterally,
• the frame accommodates guiding and motorization elements along the first axis and is designed in juxtaposable and removable length units so as to
• the position of the support of the workpiece relative to the frame is configurable.
• the geometry of the frame channels the chips/effluents in the front part, facilitating their extraction.
• the machine tool of the invention has a reduction in environmental impact due to:
• machining by chip removal constitutes the application first envisaged and preferred for the implementation of the machine tool of the invention, it can also be used for other operations, such as:
• Figure 1 is a schematic drawing of a general perspective view of an embodiment of a machining machine tool according to the invention.
• Figure 2 is a kinematic diagram of the machine tool of the invention
• Figure 3 is a schematic drawing of a perspective view of the positioning module in a deployed position
• Figure 4 is a schematic drawing of a side perspective view of the positioning module in a folded position
• Figure 4a is a schematic drawing of a bottom perspective view of the positioning module in a folded position
• Figure 5 is a schematic drawing of a sectional view along a cutting plane passing through the second and third axes of the first arm
• Figure 6 is an explanatory diagram of the operation of a position control implemented by the machine tool of the invention.
• Figure 7 is a schematic drawing of a top sectional view of the second arm
• Figure 8 is a schematic drawing of a perspective view of the wrist assembly and rotating work spindle
• Figure 9 is a schematic drawing of a detailed sectional view along a sectional plane passing through the fifth and sixth axes of the free end of the positioning module;
• Figure 10 is a schematic drawing of a perspective view of a variant of the second arm
• Figure 11 is a schematic drawing of a perspective view of a motorization variant of the first arm
• Figure 12 is a schematic drawing of a perspective view of a machine tool configuration comprising several positioning modules on the same frame
• the machining machine tool referenced M as a whole comprises a frame 100 and a positioning module P of a rotating work spindle here constituted by an electro-spindle 200 carrying a tool 210.
• a workpiece holder subassembly B is positioned in front of the frame 100 and is associated with a chip recovery and evacuation subassembly C.
• An operator O can interact with the workpiece holder subassembly,
• Figure 2 illustrates the kinematic connections implemented by the machine tool M.
• Figures 3 and 4 illustrate the positioning module P alone.
• said positioning module P is an articulated structure which ensures the movement of the tool 210 relative to the fixed frame 100 in implementing a plurality of connections on only six axes numbered from A1 to A6.
• the positioning module P comprises a carriage 300 supporting articulated arms 400 and 500 at the end of which evolves a sub-assembly forming a wrist 600 housing the electro-spindle 200.
• the positioning module P implements the connections described below.
• the carriage 300 is in sliding connection with the frame 100 for movement in horizontal translation along a first axis Al.
• the movement is motorized by means of a 110 linear motor.
• the frame 100 is preformed so as to accommodate two horizontal rails 120 and 130 arranged parallel to the first translational movement axis A1 and offset in height.
• Said carriage 300 is preformed and equipped with guide pads 310 to cooperate with said rails 120 and 130 in order to implement the slide connection along axis A1.
• the frame 100 comprises a vertical flat surface 140 with a longitudinal axis parallel to the rails 120 and 130 and intended to accommodate the secondary part 112 of the linear motor 110.
• Said flat surface 140 is arranged higher than said rails 120 and 130 and is offset laterally .
• Said carriage 300 is preformed to accommodate the primary part 111 (see fig. 4a) of the linear motor 110,
• Such an offset and raised arrangement has the advantage of bringing the motor 110 closer to the center of gravity of the positioning module P,
• the carriage 300 is preformed to guide the first arm 400 in rotation along an axis A2 parallel to the axis A1. To do this, it comprises two symmetrical bearings 320 and 330 between which a first end 410 of the first arm 400 rotates. .
• the first arm 400 is itself preformed at its second end 420 with two symmetrical bearings 430 and 440 to guide the second arm 500 in rotation along an axis A3 parallel to the axes A1 and A2.
• a first end 510 of said second arm 500 is inserted between the two bearings. 430 and 440.
• This first arm 400 comprises between the axis A2 and the axis A3, a volume concave 450 allowing an increased angular stroke of the second arm 500 which can be housed in this concavity in the folded position illustrated in Figure 4.
• the concave volume 450 starts from the lower end 410 and is defined so that in the folded position, this concave volume prevents the rear part of the electro-spindle 200 from abutting against the first arm 400 when in the folded position the electro-spindle 200 is oriented with its axis A6 intersecting the longitudinal axis of the arm 400 as illustrated by Figure 4a,
• the second arm 500 adopts a hollow tubular body and accommodates at its second end 520 a sub-assembly forming a wrist 600 which implements:
• a third motorized pivot connection for rotational movement along an axis A4 perpendicular to the axes A1, A2 and A3, and
• the electro-spindle 200 ensures the rotational movement of the tool 210 along an axis A6 perpendicular to the axis A5.
• the axis A6 of rotation of the tool 210 moves in a plane of movement passing through the axis A4 of the third pivot link
• the axis A4 of the third pivot connection merges with the axis of the tubular body constituting the second arm 500 and is positioned in the median plane defined between the two bearings 430 and 440 guiding the rotation of the pivot connection according to the axis A3 and in that confused with the first defined between the two bearings 320 and 330 proposed by the carriage 300.
• the second arm 500 is preformed so that the axis A4 is intersecting perpendicularly with the axis A5 and not intersecting with the axis A3 thanks to an offset created by the geometry of the end 510 which offsets the axis A4 corresponding to the axis of the tubular body of the second arm 500,
• All the pivot connections are motorized incorporating a geared motor composed of a motor and a reduction gear
• the pivot connections on the axes A2, A3 and A5 are implemented by two bearings each: a main bearing and a secondary bearing.
• the pivot connection implemented along the axis A2 between the lower end 410 of the arm 400 and the carriage 300 is guided by the two bearings 320 and 330.
• the drive in rotation is implemented by means of a motor 321 associated with a reducer 322.
• This motor 321 is also associated with a first encoder 323 ensuring measurement of the speed only
• the part driven in rotation of the reduction gear 322 is fixed to one side of the end 410 of the first arm 400 to transmit the rotational movement.
• the bearing 320 providing guidance on this side is called main because it is closest to the motor 321.
• the second side of the end 410 is equipped with an axial extension 331 which is guided in rotation by the second so-called secondary or recovery bearing 330 and is associated with a second encoder 332 ensuring measurement of the position,
• the part driven in rotation of the reduction gear 432 is fixed to one side of the end 510 of the second arm 500 to transmit the rotational movement.
• the bearing 430 providing guidance on this side is called main because it is closest to the motor 431.
• the second side of the end 510 is equipped with an axial extension 441 which is guided in rotation by the second so-called secondary or recovery bearing 440 and is associated with a second encoder 442 ensuring position measurement.
• the part driven in rotation of the gear motor 61 is fixed to one side of the sheath 220 housing the electro-spindle 200 to transmit the rotational movement along the axis A5.
• the bearing 610 providing guidance on this side is called main because it is closest to the gear motor 611.
• the sheath 220 on its portion arranged in opposition to that cooperating with the geared motor 611 is preformed to be guided in rotation by the second so-called secondary or recovery bearing 620 and is associated with a second encoder 622 ensuring measurement measurement of the position,
• the machine tool is controlled by a control unit 700 called CNC processing with instructions for each axis of the pivot connections with two bearings (but also that implemented with a single bearing for the axis A4) described above, a control loop:
• Each loop is equipped with a regulator designated PID (proportional, integral, derivative).
• PID is associated with a data input module including the parameter setpoint and the data returning from the loop.
• the PIDs associated with their respective input form a subset called a drive.
• the pivot link comprises a motor M associated with a gearbox kinematics G and two encoders El and E2.
• the first El encoder is a speed encoder only.
• the second encoder E2 is a position encoder symbolizing the encoders 332, 442, and 622 described above. It is located after the kinematics G of the gearboxes and allows precise feedback of the measured positions for closed loop operation of said servo.
• the position information coming from the second encoder located downstream of the gearbox returns thanks to the loop 710 downstream of the digital control unit 700 upstream of the PID processing the position setpoint.
• the motor speed is therefore directly regulated to obtain the desired position without going through the digital control unit.
• the masses of the different components are defined and distributed so that, due to the overhang formed, the reduction gears of the motors of the first and second pivot connections respectively on the axes A2 and A3 are in preload. According to a preferred embodiment, these reducers are cycloidal without clearance.
• the reduction gears of the motors of the third and fourth pivot links respectively on the axes A4 and A5 are harmonic driven.
• the machine tool M comprises a plurality of cables and pipes for supplying energy and transmitting orders and information necessary for the operation of the axes and the electro-spindle 200. These cables and pipes are arranged under the winding shape so that, during rotational movements, they are subject to bending stresses more than to torsional stresses.
• the tubular body constituting the second arm 500 is provided with a hollow core 530 in order to accommodate such a winding 540 (see Figure 8) which takes into account the rotation according to the A4 axis.
• the hollow core 530 of the second arm 500 accommodates a winding shaft 550 and a concentric sleeve 560 defining a winding volume of a single sheath grouping together cables and pipes, the radius of curvature of the cables and pipes in the winding volume changing according to the angle of rotation of the wrist 600 along the fourth axis A4.
• the jacket 560 limits the expansion of the winding in said volume.
• the winding shaft 550 is itself provided with a hollow core 551 into which a rotating joint 552 opens for the purpose of supplying hydraulic energy for the clamping and unclamping of the tool 210 .
• pivot connection along axis A5 also accommodates a slightly different winding device 630 in that each pipe or cable has a dedicated winding roller.
• the second bearing 620 of the wrist subassembly 600 guides in rotation a rotating part secured to the sheath 220 housing the electro-spindle 200.
• This rotating part is equipped with the winding device 630 for the necessary cables and pipes for the supply of electrical energy and for lubrication so that the radius of curvature of said cables and pipes varies according to the angular position of the electro-spindle along axis A5.
• gear motor 611 is crossed axially by a rotating joint 614 (seven-way according to the illustrated embodiment), for supplying hydraulic and pneumatic energy to the electro-spindle 200.
• the subassembly called wrist 600 forms an independent assembly with the electro-spindle 200 and with the winding shaft 550 and the winding 540.
• This assembly comes together introduce and fix in the second arm 500 by means of an interface flange 570 which is fixed on a fixing flange 580 fitted to the end 520 of the second arm 500.
• said assembly comprising in particular the different motors and reducers dedicated to axes 4, 5 and 6 can be easily assembled, disassembled and removed from the rest of the machine.
• a second encoder 571 (in addition to that fitted to motor 572) also equips this pivot connection along axis A4.
• the first end 510 of the second arm 500 was preformed to be accommodated between the two bearings 430 and 440 equipping the second end 420 of the first arm 400.
• FIG. 10 illustrates a different configuration with regard to the implementation of the pivot connection on the axis A3.
• said second arm 500' comprises two ends, a first end 510' crossed by the third axis of rotation A3 and a second end 520* accommodating the subassembly called wrist 600'. The difference is located at the first end 510' which is equipped with two bearings 611' and 512' to guide the second arm 500' in rotation along the third axis A3. Said two bearings 511' and 512' are in fact spaced apart. so as to come from either side of the second end 420' of the first arm 400'.
• the second end 420' crossed by the third axis of rotation A3 of the first arm 400' is equipped with two bearings 430' and 440' to guide the second arm 500' and the gear motor 431' in rotation along the third axis A3. is here arranged between the two bearings 430' and 440' of the second end 420' of the first arm 400'.
• Figure 12 illustrates such a configuration where the two positioning modules P and P’ can approach each other without their respective motorization coming into conflict. Another characteristic illustrated by this figure concerns the frame which is here designed in juxtaposable and removable length units 100a and 100b, allowing the accommodation of a plurality of positioning modules.
• Said symmetrical design can also make it possible to integrate a complementary motorization or a balancing system opposite the main motorization of the axis, with the aim of increasing machining capacities, reducing energy consumption or increasing the lifespan of components (such as reducers) as illustrated in Figure 11 or a second gear motor M2 is arranged opposite the first M1 on the symmetrical bearing 330 ensuring guidance in rotation along the axis A2,

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Robotics (AREA)
• Human Computer Interaction (AREA)
• Machine Tool Units (AREA)
• Manipulator (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=83594292

Family Applications (1)

Country Status (5)

Families Citing this family (1)

Family Cites Families (15)

• 2022
  • 2022-07-29 FR FR2207851A patent/FR3138337B1/fr active Active
• 2023
  • 2023-07-27 WO PCT/FR2023/051198 patent/WO2024023463A1/fr not_active Ceased
  • 2023-07-27 CN CN202380063911.6A patent/CN120187556A/zh active Pending
  • 2023-07-27 EP EP23776421.2A patent/EP4568807A1/de active Pending
  • 2023-07-27 JP JP2025505382A patent/JP2025524225A/ja active Pending

Also Published As

Similar Documents

Legal Events