DE102013219576B4 - Deburring tool for removing a burr from a workpiece - Google Patents

Abstract

Deburring tool (8) comprising a rotationally fixed in a drive axis of rotation (8a), two spaced apart in the longitudinal direction of the axis of rotation and extending transversely to this mounting plates (8c, 8d), each with outer peripheral edges, of which at least one longitudinally displaceable on the axis of rotation ( 8a) is arranged, between the Aufspanntellern (8c, 8d) arranged compression spring for the realization of a defined bias between the Aufspanntellern (8c, 8d), and at least one between the Aufspanntellern (8c, 8d) extending cable, thereby marked, DASS the tensioning plates (8c, 8d) deflecting elements are provided, and that the rope is formed in one piece (8b) which extends around the deflection points between the tensioning plates (8c, 8d), that the deflection elements comprise deflection rollers (8f) and that the deflection rollers (8) 8f) comprise brakes or position fixing means for the cable (8b) are provided.

Description

The invention relates to a deburring tool according to the preamble of claim 1 for carrying out a method for deburring workpieces, in particular injection-molded parts.

State of the art

Such a deburring tool comprises a rotational axis which can be connected to a rotating drive and has a longitudinal axis, two clamping plates arranged spaced apart from one another along the rotational axis and extending transversely thereto, each having outer peripheral edges. A mounting plate is longitudinally displaceable and another fixedly arranged on the axis of rotation. A coil spring arranged between the tensioning plates realizes a defined pretension between the tensioning plates for clamping a plurality of wires extending at the peripheral edges between the tensioning plates. Driven by a spindle drive, the wires form a body of revolution, which is guided to remove the burr along the workpiece.

A generic device is from the DE 296 15 629 U1 known.

The deburring tool disclosed in this publication comprises a central axis of rotation which can be clamped in a rotating drive and two clamping plates which are spaced apart from one another and extend transversely thereto, which are arranged longitudinally displaceably on the axis of rotation and spaced from one another by a compression spring. At the outer circumferential edges of the spaced-apart chuck plates, a plurality of individual individual wires are arranged to extend between the plates, which extend substantially collinear with the axis of rotation. During the rotation of the axis of rotation, these wires extending between the clamping plates bulge outwards due to the centrifugal force and form a rotationally curved body which bulges outward in a convex manner, the pressure spring acting between the clamping plates realizing a defined pretensioning. The rotating deburring tool is moved to carry out the deburring process with the rotary rotary body along the workpiece, ie with the axis of rotation extending substantially transversely to the longitudinal direction of the ridge to be removed.

This deburring tool is used in particular for removing edges on objects, in particular of plastic parts, particularly preferably of mold release burrs, which arise along the location of the tool separation (separation between the two mold halves) at the joints of the two parts of an injection mold.

Another device of this kind is from the DE 44 45 592 A1 known. The DE 201 08 446 U1 discloses a generic device for a similar purpose.

Disadvantages of the prior art

This known method and the deburring tool used for its implementation have the disadvantage that the individual wires extending parallel to the axis of rotation between the plates have relatively rigid or even irreversible properties, so that a deformed individual wire no longer returns to its original shape. It thus often comes to damage the desired nominal contour of the object, because the individual wires can lose too much material uncontrolled. In this respect, the known method is by no means applicable to the removal of mold release burrs at points of the workpiece or injection-molded part which are visible to the outside in the later installed state. The known method is far too inaccurate for the processing of visible, high-quality parts.

When an edge of a workpiece for removing the burr is inserted into the rotating tool or the deburring tool is guided along the workpiece, the individual wires are pressed inwards by the workpiece. Due to the material properties of the individual wires and the spring force, although these try to return to the original position, but they can not fully recover. In addition, the spring force is too low to stretch the individual wires again as possible in a straight alignment. This leads to process inaccuracies, since the desired defined curve of the individual wires can not be taken in each case. In addition, this leads to unclean edge curves, so that no process sequences with desired product qualities can be realized. For this reason, the known from the prior art deburring tools are not used for workpieces with visible edges, ie edges that are visible to a viewer in the installed state and at a later date possibly still refined (painted, chrome, etc.).

This is also because the single-wire or bundle clamping promotes inaccuracies in the form of different voltages between the individual wires with each other, which can cause a forward or backward standing of the individual wires. This results in inaccuracies that are reflected negatively in the deburring image. A constant distance of the individual wires to one another does not allow the clamping concept known from the prior art.

Finally, damage or even tearing of individual wires for the time being unnoticed remain, as fewer individual wires withstand the compressive stress of the spring. The deburring on the workpieces can therefore be unnoticed worse. The process capability for the mass production is conditional or not at all given. In addition, an imbalance can be noticeable if only certain individual wires break.

In summary, with the existing deburring methods for injection-molded parts for the automotive industry, only a maximum of machining of "Class B" surfaces is possible, that is to say surfaces which are not visible to a viewer from the normal perspective and the supporting structure of an object.

task

Based on this prior art, the present invention seeks to at least partially avoid these disadvantages and in particular to provide a deburring, the deburring of "Class A" -surfaces, namely visible free-form surfaces in the exterior and interior area (visible places on the end product), without any later surface defects being visible on the finished (lacquered, chrome-plated, etc.) articles. Because refined plastic parts assume a shiny shape, on which surface defects are directly visible and do not appear in an unfinished plastic part, a particularly delicate deburring process or a deburring process for the production of workpieces of special quality is desired.

Invention / Technical Solution

This object is achieved by a deburring tool with the features of claim 1. According to the invention, the object is achieved in a deburring tool of the type mentioned essentially already in that the Aufspannteller each have a plurality of deflection, around which a one-piece rope meandering, ie to the deflection points extending continuously back and forth between the mounting plates extends, that the deflection elements comprise deflection rollers and that the deflection rollers comprise brakes or position fixing means are provided for the rope. The rope is preferably designed as a steel wire rope, but can also be made of another tough material, eg. As a plastic such as KEVLAR exist. During the rotation of this deburring tool with a drive, preferably by means of a compact stepper or servo motor, the rope produces a rotating jacket surface which is self-tolerant due to the material properties and / or the structure of the cable matched to the material of the workpiece and thus only the Burr away, but no unwanted material removal of the target contour of the workpiece makes. The deflection points are preferably formed as pins which protrude radially outward from the deflecting plates, sometimes with a groove, notch or the like, through which the circulating cable is fixed in position.

Increased service life can be achieved by increasing the radii of the deflection points, with a radius of at least 4 mm has proven to be particularly useful.

Due to the pulleys, particularly long service life can be achieved at the deflection points. It has been shown that these pulleys to achieve the desired life of the steel wire rope must have a certain minimum effective diameter. Particularly advantageous is a minimum effective diameter of 8 mm for the pulleys has proven. Incidentally, 8 mm is almost the smallest size of the special pulleys on the market. Reducing the diameters would drastically reduce the service life of the ropes so that they would break after the shortest possible use time. Larger diameters would unnecessarily increase the tool in its overall diameter, so that complex geometries with narrow radii or geometry gradients could no longer be deburred.

For the precise alignment, an axially parallel extension of the cables from one holding plate to the opposite has proven to be the most suitable arrangement, since in this arrangement no transverse forces acting on the cable occur, which cause a movement ("turning") of the cable. One would also like to take advantage of the endless rope to be able to replace the tool quickly and easily, if a rope should wear or tear. Because changing a rope, which only needs to be placed around the individual deflection points, is of course much easier to implement than re-clamping several individual cables between the tensioning plates.

The material of the deflection roller is made of plastic, preferably of polyamide (PA), and the deflection rollers preferably comprise precision ball bearings, particularly preferred are closed ball bearings to reduce contamination. Ball bearings have certain advantages over plain bearings, which tend to become soiled very quickly. An increased friction would be the result.

Due to this minimum effective diameter of the deflection rollers, however, they must have a certain distance from each other (so-called division) in the case of two adjoining deflection rollers on a mounting plate, which by the minimum distance of two almost adjacent deflection rollers is limited to a chuck, but is preferably designed so that in each case two on a first Aufspannteller on the lateral surface adjacent pulleys are spaced from each other about the diameter of a guide roller and the pulleys on the second Aufspannteller have the same pitch, but the Aufspannteller to a Angle or a measure are offset from each other, which corresponds to the diameter of a deflection roller. Thus, when the rope is stretched, the tread of a first deflection roller on the first tensioning plate is followed by a circling strand of a second deflection roller on the - opposite - second tensioning plate whose running surface then merges again into a circling strand of a third deflection roller on the in turn first tensioning plate, etc. Through this Training the rope extends collinear to the axis of rotation, whereby lateral forces on the rope during the deburring process are completely avoided and thus no rotation of the rope occurs.

This division, ie the number of pulleys and the distance between two adjacent pulleys on a mounting plate can be adjusted as needed. Preferably, the pulleys on the same effective diameter. But it is also conceivable in principle to use pulleys of different diameters.

In the development of the invention, it has been shown that the process sequence and the product quality are dependent on the pitch (distance from a center of a deflection point to the next on the lateral surface of a mounting plate). Generally, the smaller the pitch, the fewer ropes are engaged per revolution at the same speed and feed rate. By changing these two parameters, the desired result can be achieved at different pitches. It has been shown, for example, that a division of 8 has the advantage that several cable sections are loaded during the deburring process, which has a positive effect on the life of the rope and also reduces the speed, but the tool diameter must be designed so large that the Rope sections are arranged parallel to each other. For this reason, this tool is no longer in a position, depending on deburring narrow geometry curves such as an S-curve deburring. Thus, a smaller pitch is used, preferably a 6 pitch, which causes the tool to assume the smallest possible diameter. A reduction of the diameter is not possible without negative influences, since the individual sections of the rope must have a certain clearance to the interior of the tool in the direction of the axis of rotation, which is exhausted as the article to be deburred article geometry in the direction of the axis of rotation. During deburring the bulbous arrangement of the rope is lifted by centrifugal forces and pressed the rope in the direction of the tool axis. On the one hand, there is the effect that the cable with large delivery far around the area to be deburred and nestles, on the other hand, this delivery are also limits, since the desired result can be achieved only in a certain Zustellbereich. This allows for variable or controllable results if desired, because the forces arising during deburring vary depending on the delivery and, to a certain extent, adapt independently.

A arranged between the mounting plates compression spring with linear characteristic aims at a nearly constant increase in force over the entire delivery area, wherein the workpiece counteracting force per millimeter delivery increases by a certain amount. The resulting characteristic can be varied by selecting the compression spring used.

One embodiment provides for such an arrangement of the deflection rollers on the mounting plates, that in each case two deflection rollers lying opposite one another form a pair of rollers, wherein the second deflection roller of the second mounting plate begins where the deflection roller of the first opposing mounting plate ends. Thus, the stretched between such Umlenkrollenpaar rope extends substantially parallel to the axis of rotation. The offset to the next Umlenkrollenpaar is then distanced from an adjacent Umlenkrollenpaar, so that the cable extends obliquely after the circulation of a Umlenkrollenpaars to the next Umlenkrollenpaar. Just this oblique arrangement causes the "dipping" of the workpiece in the tool shear forces that rotate the rope around the pulleys or "run". It is more suitable to adapt the diameter of the mounting plates to the utilized pitch and deflection roller size. By this vote all cable sections can be aligned parallel to each other. Transverse forces are thus effectively avoided.

By using ball-bearing pulleys with a corresponding minimum diameter, the service life can be significantly increased, so this is a particularly preferred embodiment.

But the pulleys are also required in an ideally stationary, so not rotating rope, because when immersing the workpiece in the tool, the stress on the rope at the deflection points is reduced by the pulleys. Without the pulleys would be the Stress on the rope too strong and thus the service life too low.

Particularly good results can be achieved with a stationary, thus position-fixed rope, for which purpose either one or more brakes can be provided to prevent rotation of the rope. The brake can z. B. comprise one or more O-rings at the deflection points, which clamp the elastically extending around the deflection points rope. Another way to fix the position is the provision of Seilendverbindungen on the rope, z. As balls, rope thimbles or the like, which are pushed onto the ends of the rope and then compressed or sprayed to connect the ends or captively connected by means of a laser or known welding methods with the rope. This Seilendverbindungen are then used in receiving openings, preferably provided in the mounting plates. Finally, it is also possible to use a closed rope in the form of a closed loop. These two last embodiments have the advantage that the rope is particularly easy replaceable or exchangeable, which simplifies maintenance.

The use of pulleys made braking or securing the rope unnecessary in the course of development. It has been found that with orthogonal orientation (90 °) of the deburring tool to the highest point of the ridge on the article, all occurring lateral forces could be significantly minimized or almost avoided, so that the rope has barely the desire for movement. By this training, therefore, no abnormally high forces arise more in the deflection, which can lead to a tear of the rope in other embodiments.

The article or workpiece to be machined is clamped horizontally in its article receptacle, which already represents an inclined position to the tool demolding during injection molding. The highest point of the deburring burr thus points horizontally away from the article and can therefore be achieved and deburred in the best possible way with a vertically aligned deburring tool. Furthermore, this concept simplifies the teach-in of the robot, which guides the deburring tool, since for the most part the tool only has to be moved in two levels (horizontal, vertical). Although both concepts are conceivable - firstly moving the article by means of a robot with a fixed deburring tool and secondly moving the deburring tool by means of a robot while the article is stationary - the latter is recommended due to various advantages in terms of process technology. Adjusting the tool at a certain angle to the article is almost insignificant, as long as the parting ridge does not "jump" out of position due to the design of the article. Only areas on articles that are not in the direction of removal of the injection mold can only be reached by moving several axes of the robot with the deburring tool. The principle is maintained, however, that the tool is at best aligned always orthogonal to the highest point of the mold parting ridge. With workpieces that require a consistently horizontal alignment, it is also possible to move with linear systems instead of a 6-axis robot. These are usually cheaper to buy.

The use of a steel wire rope, preferably made of stainless steel achieved particularly good results. Deburring on and on visible surfaces is only possible by means of a rope that is as flexible as possible, without causing an undesirable change in the article design (nominal contour). By changing the compression spring force, preload and distance between the mounting plates (effective length of the cable sections), the cuddly effect of the deburring tool can be fine-tuned as required.

Ropes according to the invention, that is to say closed ropes in the form of a loop and yet relatively small diameters, in particular wire ropes, have hitherto not existed on the market, so that such a closed wire rope only had to be developed in the context of the invention. The joining of the free ends of the steel wire rope can be done in different ways; either by using rope end connectors or by splicing.

Through the use of pulleys to reduce friction and / or the parallel clamping of the cables, lateral forces acting on the rope during the process are avoided to the extent that even a tightly clamped rope can be used. This solution is better for this reason, since there is no connection point of the wire rope, which can irregularly engage during deburring. Consequently, prefabricated cables with cable end connections, also termed terminals, can be used by this design. These are z. B. hung in a sink on the mounting plates and avoid jumping out of the rope when tensioned. These are now ropes of a certain length, which have on both sides at their ends Seilendverbindungen (primarily bullets). These terminals are either pressed or sprayed on according to the prior art. Ropes of a certain length are particularly suitable for the production and can be used optionally. As an "endless rope" is referred to in the context of the invention, a taken from a roll rope, which is taken from the roll, cut to length and the Finally, ends are joined together to form a closed loop, which z. B. by means of nodes, splices, lasers, squeezing, etc. can take place. Prefabricated ropes are ropes that have already been cut to length by the manufacturer and are equipped with rope end connections (rope end terminals). Prefabricated ropes are preferably used for the invention. Closed rope loops are, according to experience, cheaper to buy, but pre-fabricated ropes can be clamped into the deburring tool faster and easier.

A position fixation of the steel wire rope can z. B. via attaching the Seilendverbindung within one of the two Aufspannteller or alternatively in both Aufspanntellern. For this purpose, in a mounting plate or in both mounting plates laterally a slot may be provided with a subsequent depression, in which the Seilendverbindung, primarily a ball is inserted.

To realize a simple captive use of the rope on the deburring a quick-release system is preferably used. In addition or alternatively, a locking ring, such as a clamping ring with quick release as cover protection can be used. This measure prevents jumping out of the rope end including terminals (Seilendverbindung) with possible relief of the tool. Clamping is then no longer necessary because the rope has no way to solve. Relief occurs, for example, when tearing the rope. A wandering of a broken rope is thus avoided.

In deburring tools known from the prior art, only a small area in the middle of the individual wires (about 4 mm in length) could always be used for deburring. The remaining length of the wires was used only for clamping at the top and bottom of the mounting plate. In order to realize the economic utilization of the rope according to the invention, the deburring tool may comprise a transport device for the rope, z. B. with a rotatable coil. This transport device is preferably designed to move the cable either automatically or manually after a certain number of operations, so that the worn cable regions (eg 12 pieces in a 2 × 6 parting) leave the engagement region in the center of the tool be moved and engage unused unused cable lengths. By this approach, a multiple utilization of the rope is realized and the setup operations are also further reduced by this training, which improves the economy. The closed rope or the rope loop is placed crosswise around the reel plate in a designated groove provided around the outer surface of the mounting plate and the rope thimbles at the ends of the cable loop are in sinks, z. B. formed in the end face of the mounting plate, inserted. By means of a gear acting between the coil and the rotatably connected to the axle chuck toothing, the coil can be moved clocked depending on the rotation. The number of teeth dictates the path of a bar. The rope can thus be further clocked by a full effective length of the rope spanned between two pulleys, so that each area of the rope is used for deburring. The indexing can also be done manually.

The rope is guided laterally crossing on the fixed mounting plate below the coil so that pulled at the rotation of the coil at the one end of the rope and given in at the other end of the rope to realize the cycled rope circulation. By forming certain numbers of teeth between the ratchet and coil a linear movement of the rope is realized to the desired extent during rotation of the coil and can also be adjusted as needed by changing the number of teeth or ratchet training. By means of a switching lever, the direction of the ratchet and thus the rope circulation is changeable and can be operated by the worker also for the rope exchange.

Preferably, a rotation of the mounting plate is also provided on the axis of rotation, z. B. in the form of a positive shaft-hub connection or by means of a feather key. In this way, a rear-hemming movement of the at least one movable clamping plate is compensated by different mass moments of inertia. The lack of anti-rotation has sometimes led in the prior art to a twist and thus to a higher stress on the individual wires. Due to the proposed rotation, this problem is effectively excluded, so that the deburring tool is thus dependent on the rotational speed of the tool and the workpiece contour dipping during operation. For this reason, the wires take depending on the speed of an undefined oblique position with respect to the tool axis. The deburring result can therefore vary greatly.

In a generic deburring method, the object mentioned at the outset is already achieved by detecting forces occurring during the deburring process or process for realizing a permanently uniform contact force. In this way, occurring in the prior art too high contact forces, which can cause an undesirable change in the desired contour on the workpiece, effectively avoided.

Preferably, forces and moments are detected via a force-moment sensor. A particularly accurate process design is by means of a 6-axis force-torque sensor feasible. It can be provided interface compatibility for a variety of applications through the existing interfaces, such as Ethernet, Ethernet / IP, DeviceNet and a CAN bus interface, etc. The sensors can also be used for various machining tasks such as deburring, grinding and polishing. These sensors can detect very small forces and moments. With these, it is even possible to automate difficult assembly, machining and finishing tasks that previously could only be performed by hand or by complex special machines, because these sensors can detect both forces and moments in all six degrees of freedom. The signal output is preferably via high-speed outputs via Ethernet or CAN, so that even highly dynamic control concepts can be realized. For remote monitoring, such a sensor can easily be connected to the existing network. The system settings can be configured, displayed and set via a web interface. A visualization of the six-axis measurements is possible in real time. Cable break detection, overload protection and temperature compensation are also typical features of such a sensor. The system preferably consists of the sensor, shielded robotic (towable) DeviceNet cables and a net box with an interface, in particular Ethernet and DeviceNet / Can-Bus interface. Due to the 6-axis force-moment sensor, a crack of the rope is immediately recognizable. In such a case, the force goes to zero, the robot increases up to a certain range and registers no further force increase. The robot then switches off and issues an error message. Preferably, a software limit switch is programmed, otherwise the non-ending correction would lead to a collision. When programming the curve shape of the target contour for machining (teaching), striking, freely selected points along the contour to be machined are manually traversed with the robot. The sensor detects manual pulling and pushing on the robot head and moving the robot by hand. However, the robot can also be moved as usual via the commonly used joystick of the teach panel. Once the coarse teach points have been set, the course of the learn run begins. This is part of the software. Thus, the exact trajectory of the desired contour is programmed precisely and the predetermined force is maintained on the system side during the deburring process. During deburring, the robot then moves with power. If the force deviates, the orbit is corrected. Component and position tolerances can henceforth be neglected. Furthermore, a speed option can be added to the robot program. This functionality maintains a constant machining pressure of the robot by changing the robot speed. If the burr changes along a machining path, a controlled removal rate can be achieved on the component. The deburring tool, which is already tolerant due to the elastic structure, thus moves a "clean" path, which creates a safe process.

When deburring, so formed by the rotation of the rope rotating surface with the workpiece, charge differences can arise, which can cause a charge of the component and thus cause dust and dirt adhesion. These adhesions are visible in the form of surface ripples, specks or pimples after the painting process. Since these surface defects can be seen not only on the deburred surface, but also in their vicinity, it has been shown that dust or removed material deposited on and on the machined surface. This effect often occurs due to differences in the charge of plastic articles. In the preferred method implementation, these adhesions of dust and dirt, by carrying out charge-reducing measures can be prevented, such. As the ionization, the charge dissipation by means of brushes, preferably using carbon brushes, ostrich feathers or the forward or lagging by means of antistatic materials, or those that derive or neutralize charges. Thus, if the disturbances are caused only by dust and dirt, by integrating one of the previously described methods a further post-processing - a finish process - can be omitted.

Particularly well can be processed with the Entgratwerkzeug invention complex radii in the form of curves or surface curves, of which a burr is to be removed. The proposed device just enough material is removed to remove a fine burr, but in no way changed the design of the article, so the target contour or even damaged.

For driving the axis of rotation of the deburring tool, any commercially available drive unit can be used. Elements such as reversing switches, inverters or alternative components or control elements within the process control / regulation, keep open the possibility to also change the speed, direction of rotation, acceleration and deceleration ramps, etc. of the deburring tool. The use of a deburring spindle or a drive (electric, pneumatic, etc.) flanged to the robot is also possible. Preferably, a 6-axis force-torque sensor between the robot flange and the drive unit (spindle, motor, etc.) or the workpiece holder is used, so that, depending on the process design - either the workpiece or the article or the tool guided by the robot - occurring component tolerances considered and deburring track corrections can be made. Component tolerances between multiple batches, positional tolerances within article fixtures, etc. can be detected and compensated in real time during the deburring process. The force sensor, preferably designed as a 6-axis force-moment sensor, communicates with the robot controller, which consequently makes a path correction. A consistent delivery or a resulting force is thus guaranteed.

The teaching process of the robot (teach-in and programming of the deburring track) is also greatly simplified. The delivery of the ropes of the deburring tool into the contour of the workpiece can be carried out in a simplified manner. The force sensor can be ordered to indicate when a certain counterforce is generated by the delivery, so that for the first time a continuous and consistent Entgratprozess is feasible. Preferably, a special sensor system (eg in the form of an optoelectronic sensor or using optical fiber technology, etc.) is provided for checking defects on the cable, which z. B. stops the deburring and possibly reports a fault. From this point on, the deburring tool can compensate and eliminate automatically due to its "cuddly" and thus self-tolerant property occurring tolerances.

Particularly good deburring results are achieved with a synchronous deburring on the workpiece. In this case, the rope of the rotating tool moves in the engagement region in the direction of the vector of the workpiece feed direction. In contrast to counter-run deburring during synchronized deburring, the force is greatest immediately at the cable entry, but then decreases continuously. The material removal becomes thinner towards the rope outlet until it is finally peeled off, which results in a smoother surface in relation to the mating operation.

The deburring process can be carried out either alone or in combination with other, for example, deburring, cutting, grinding or polishing processes. Thus, with a workpiece clamping on a robot-guided workpiece device, the workpiece can optionally be guided along one or more processing stations. In addition to the robot-assisted guiding of the deburring tool along a stationary workpiece, a movement of the workpiece can therefore also or alternatively take place, which preferably also takes place in a robot-assisted manner. To minimize the need for machining centers, up to four robots can be controlled at the same time, with the robots working together to work on complex coordinated patterns. Furthermore, the dynamic switching between independent and coordinated movements is also possible. For example, during the deburring movement by a robot, the workpiece is moved by an opposing robot, so that the sum of both movements gives the desired feed rate. In this way, complex geometry curves can be processed particularly efficiently.

Naturally, tool stations, service stations and cleaning stations can be used in the process sequence. While the deburring process is running, further deburring tools can be cleaned and fitted with new ropes. The already mentioned combination methods, such as the use of ionizers, wipes, polishing wheels, brushes, ostrich feathers, heating elements, and also other known combination methods can optionally be added.

Particularly good results can be achieved by combining the deburring with other methods, for example by using a further upstream or downstream processing step with an axis of rotation in the longitudinal direction enclosing and can be filled via compressed air, flexible hollow cylinder which is rotatably connected to the axis of rotation and similar cuddly behaves and with the help of a pre-deburring or finishing process can be made with fine grinding / polishing material. On this various sliding and polishing rollers can be postponed. The amount of air in the elastic hollow cylinder can, for. B. be changed by means of a commercial ball pump, resulting in a rudimentary comparable "cuddly" effect. With only light delivery of the article in this tool, this process can also be used as a finish process. Optionally, a suitable abrasive can also be "slipped over" via this air bellows. The deburring process can therefore be used individually, in combination with other deburring or as a finish process.

Furthermore, interfaces can be created that allow the robot to change the direction of rotation of the deburring tool, depending on the position of the article on the deburring tool. Tangential approach and retraction from the geometry to be deburred can be achieved without producing visible parts on the workpiece. Because it is always possible to deburr while maintaining synchronous operation, regardless of the feed direction, a particularly fast process with a short cycle time can be achieved.

Preferably, in the tool-guided deburring, so if the deburring tool together Drive unit is moved, for example, with a 6-axis robot or an alternative positioning unit, the workpiece or the article firmly clamped in an article recording and thus statically positioned. If required, fixed or slidable contour pieces attached to the article holder can be used, which cause the deburring tool not to "hook" at the end of a contour or during a contour jump because of its direction of rotation, thus causing damage to the cable. By this procedure, the deburring tool can therefore be carried out paragraph-free over the end of a contour and moved on the contour piece away from the article. Depending on the article geometry, a displaceable contour piece, moved, for example, by a lifting cylinder, go back and realize the further deburring with the tool in a different direction.

By using coded workpiece or article recordings, the deposited deburring program can be called up directly when plugging it onto the robot and, by using a suitable suction device, for example with C-bracket support for concentricity support of the deburring tool, a virtually dirt-free deburring can be realized, so that accumulating dust is sucked directly after deburring and thus surface defects are effectively prevented. Further process and product optimization can be achieved by using an ionizer, which is preferably mounted on the C-bracket, which fixes the deburring tool with the axis of rotation at the top and bottom. This ionizer on the one hand causes the neutralization of charge differences and on the other hand, the air flow causes a targeted direction of the Entgratstaubs in the direction of the suction unit.

In a preferred further development, the removal of material from the workpiece is improved by heating, wherein this heating can take place either on the workpiece or on the tool. Heated material is easier to remove and heating of the already processed surface realizes significantly better surface qualities with considerably smoother surfaces.

For heating, the known heating methods and heating elements used for this purpose can be used. To heat the rope, a plasma flame has been found to be particularly useful.

The heating of the workpiece can be done for example by means of hot air or a flame. The preferred embodiment for heating the workpiece uses as a heating element a radiant heater, which is arranged next to workpiece / or tool prior to engagement with the counterpart. The hitherto customary and hitherto described method comprises heating before deburring. For finishing, ie the finishing of the product, the heating after deburring is particularly advantageous, because thus the surfaces of special quality described above are achieved.

Another embodiment provides an induction device which heats the plates and thus the steel wire rope. This may for example comprise an induction coil or induction collar, which surrounds the outer peripheral surfaces of the plates, but without touching them. The advantage of this solution is that this induction device is independent of the tool, so it does not have to rotate with it; this simplifies the construction considerably.

Decisive for the smooth process is the correct programming or teaching (so-called teaching) of the robot, in which the trajectory of the target contour to be traveled with the tool is taught on the workpiece and always - depending on the location of the ridge in the room - a possible vertical position of the axis of rotation of the deburring tool to Scheiteilpunkt the ridge is realized. Basically, there are two possibilities: On the one hand teaching (teaching) by hand, in which a programmer along the robot Entgratvorrichtung (sensor, holder, drive unit, deburring tool, ionizer, etc.) moves in the desired position in relation to the workpiece and so striking Programmed points. In this case, certain axes of the robot can be locked, so that z. B. only a movement of the deburring tool in the horizontal and / or vertical plane is possible. And on the other hand, the programming of the desired trajectory with the help of a teach panel or the like. Then, the robot moves this target contour after command input alone, this detected by means of the force sensor itself that always a defined contact force is applied to avoid damage to the workpiece or a change in the desired contour beyond the desired decrease of the ridge, which also along the Target contour different pressing forces of the tool can be realized as needed. As a result, the system detects due to the force sensor during later processing any deviation from the target path and / or target contact force, so that correction movements to achieve the always optimal target contact force depending on the target contour can be realized.

An auxiliary device for the maintenance and clamping of the rope in the deburring tool allows the effortless clamping of such a prefabricated rope by one or both Aufspannteller in the opposite direction pushes together. The rope can thus be used without tension. Only when hanging the last rope end connection, the rope tension is applied by the spring. After all components have been fastened, the auxiliary device is unlocked again, wherein, for example, a ball catch prevents the debarking tool and thus the rope from jumping out of the holding device before, during and after the cable assembly / disassembly. In the relaxed state, the tool is under a predetermined preload.

A particularly accurate process control can be realized by clamping or rotatable fixing of the deburring tool in the deburring device, preferably via a C-bracket.

Further details, advantages and features of the invention can be taken from the following part of the description, in which an embodiment of the device according to the invention is explained in more detail with reference to 16 drawings. Show it:

1 a perspective view of a deburring robot according to the invention, comprising a 6-axis robot and a deburring device attached thereto with a deburring tool;

2 an enlarged perspective view of the deburring at the end of the free arm of the robot of the processing unit;

3 an enlarged perspective view of the deburring device;

4 a perspective enlarged side view of the deburring tool without rope;

5 a plan view of the upper end of the deburring tool with a 6-pitch;

6 a side view of the deburring tool to illustrate the parallelism of the rope in the installed position;

7 a perspective view of the quick release device for the deburring tool;

8th an alternative deburring tool, which develops a cuddly property depending on the air pressure;

9 a plan view of the suction hopper of the deburring device;

10 a schematic structure of a processing cell;

11 an enlarged view of a deburring device with a transport spool for the rope;

12 a perspective view of an article device with workpiece without an attached contour piece;

13 a perspective view of the article device with workpiece according to 12 with attached contour piece;

14 a perspective enlarged plan view of the top of a mounting plate;

15 a perspective view of a deburring tool with a transport device for the rope; and

16 a perspective view of an alternative transport device for the rope.

Accordingly, the deburring robot consists of a 6-axis articulated robot 2 and deburring device 4 at the free processing end of the articulated arm robot 2 , Between that in its entirety with 4 characterized deburring device 4 and the articulated arm robot 2 is a force sensor 6 arranged. In the present case, this force sensor is designed as a 6-axis force-moment sensor, which thus can detect and respond to continuously occurring forces and moments in six axes during the deburring process.

The deburring device 4 itself consists of a servomotor 4a , in the installation position lower end, on its upper side an annular suction funnel 4b the drive axle 4c is formed enclosing. The drive axle 4c drives the axis of rotation 8a of the deburring tool 8th at. Laterally offset from the axis of rotation 8a towards the robot flange, extends parallel to the axis of rotation 8a a C-bracket bracket 4d with ball bearing, which is the upper free end of the axis of rotation 8a of the deburring tool 8th rotatably fixed in position. The robot flange is also a wall-like, arcuately curved splash guard 4e about the length of the C-bracket bracket 4d arranged to cause contamination of the force sensor 6 and the robot flange.

On top of the horizontal holding section of the C-bracket bracket 4d are two ionizing spray nozzles 4f . 4g arranged, which in installation position at the upper end of the deburring tool 8th , laterally offset downwards. These ionizing spray nozzles 4f . 4g prevent buildup of charge on the tool and / or workpiece during the deburring process.

The suction funnel 4b also has two radially extending to the right and to the left suction nozzle 4h . 4i on, to which a suction hose can be connected to suck off the abrasion arising during deburring.

The 3 shows an enlarged perspective view of the upper end of the deburring device 4 without the servomotor.

4 shows a perspective view of the deburring tool 8th itself, so taken from the deburring device 4 but without clamped rope 8b ,

The deburring device 4 includes in the installation position lower end a servomotor 4a for driving the central axis of rotation 8a of the deburring tool 8th ,

The deburring tool 8th further includes two along the axis of rotation 8a spaced apart and extending transversely to this plate-like mounting plate 8c . 8d each defining outer peripheral edges. From these mounting plates 8c . 8d is a first and in mounting position in the deburring below arranged Aufspannteller 8c fixed, so not axially displaceable and torsionally rigid with the axis of rotation 8a connected, whereas the second and in the installed position located above Aufspannteller 8d while rotatably with the axis of rotation 8a is connected, but longitudinally displaceable along this axis of rotation 8a is mobile. Between the lower mounting plate 8c and the upper mounting plate 8d the axis of rotation coaxially enclosing a compression spring is arranged, which rests in installation position against two attachment pieces with Anlagebündern and thus the upper Aufspannteller 8d from the lower mounting plate 8c pushes.

The axial adjustment of the upper clamping plate 8d is limited by a clamp-like quick release 8e which is on the axis of rotation 8a above the upper mounting plate 8d can be placed and consists of a the outer diameter of the upper clamping plate 8d corresponding clamping body with a radially to an inner passage opening for the axis of rotation 8a extending slot. The tensioning body, which is elastic to some extent through the slot, is in a relative position on the axis of rotation via a clamping screw which extends transversely to the direction of extension of the slot and can be actuated via an eccentric 8a In the set position, it can be fixed in position so that it can be placed in the installation position on the deburring tool 8th stretched rope 8b to apply the required clamping force.

At the outer peripheral edges of the mounting plate 8c . 8d are equidistantly spaced from one another radially projecting pins provided on which a plurality of ball-mounted pulleys 8f are rotatably arranged. These pulleys 8f are equally spaced both on the lower chuck 8c as well as on the upper mounting plate 8d provided, in the present case, each with six pulleys 8f , resulting in a six-division. According to the 6 which is a plan view of the deburring tool 8th represents are the spaghetti 8c . 8d at such an angle relative to the axis of rotation 8a offset from each other, that the pulleys 8f of the lower clamping plate 8c always between two adjacent pulleys 8f of the upper mounting plate 8b lie and vice versa. By this arrangement, in the 7 illustrated axially parallel alignment of the rope 8b ensured in the installed position, which means that that around the pulleys 8f tight rope 8b always parallel to the axis of rotation when installed 8a extends. By this training, effective lateral forces are on the rope when deburring 8b avoided causing an unwanted rotation of the rope 8b at the deburring tool 8th would cause.

The 7 shows a perspective view of the quick release device for clamping the rope 8b on the pulleys 8f of the deburring tool 8th , This quick release device 10 includes a bow-shaped holder 10a comprising a horizontal bottom portion and two integrally formed at this end and this transversely to this bottom portion parallel to each other upwardly extending retaining legs 10b . 10c aligned with insertion openings for insertion of the axis of rotation 8a of the deburring tool 8th ,

8th shows an alternative deburring tool 20 with a central axis of rotation 20a concentrically enclosing, elastic hollow cylinder 20b , On this hollow cylinder 20b can a ring-cylindrical Abriebmantel 20c rotatably attached. The hollow cylinder 20b can be filled as needed with air or other fluid to realize more or less pressure when deburring. Even with this deburring tool, the inventive self-adjusting material removal can be realized on the workpiece, which has enough contact pressure for removing a Formtrenngrats, but does not make a change in the desired contour on the workpiece. For exact Proessführung the tool is preferably fixed on both sides, but this need not be the case. The axis of rotation may be hollow, so that the air pressure can be regulated. The compressed air can also be drained via a drain valve.

10 shows the schematic structure of a Entgrat cell with the deburring robot. During machining, a central articulated robot engages 12 the workpiece. Instead of this on two downstream polishing wheels 14 . 16 It passes rigidly to the article and presents it to the user Entgratroboter 18 , which is equipped with in the manner described above with a sensitive 6-axis force-moment sensor and thus can detect and process even the smallest forces below 1 N. The deburring device with the compact stepper or servo motor, which drives the deburring tool, is mounted on this sensor. Occurring tolerances (robot tolerance, component tolerances, position tolerances, etc.) are detected by the sensor and corrected in the overall process. The article can also be added to the polishing pads without additional storing and picking up 14 . 16 be passed.

Optionally, another 6-axis force / torque sensor can also be connected to the central articulated robot if required 12 the Entatz cell be mounted to enlarge the manufacturing window of the polishing process. The robot can adjust when the discs wear.

If the workpiece has already been completely processed after deburring, then both processes (deburring by means of a deburring robot) can be performed 18 and polishing 14 . 16 be separated from each other. The net machining time can be drastically reduced by deburring since polishing wheels take much longer to remove a burr than the proposed deburring process. These can optionally be used effectively for polishing after deburring.

11 shows an enlarged side view of the deburring tool 8th or the upper mounting plate 8d with a built-in top coil for clocked transport of the rope 8b ,

The 12 and 13 show perspective views of the front end of a workpiece 24 with a target contour to be machined 24a , where at the 13 a contour piece 22 on the end of the workpiece 24 is attached. This contour piece 22 avoids the hooking of the rope of the deburring tool, if this along the desired contour 24a drives and reaches the end, here the front end. The contour piece 22 extends so to speak, the target contour such that at the front edge 24b Generally, at the end of the workpiece, there is no sudden tear which could damage the edge. It has also been found that particularly good product qualities are achievable in that the rotation of the deburring tool and the feed direction are in synchronism, in the present case, when the deburring tool from the rear end of 12 and 13 to the front end of the workpiece 24 moves while doing a levorotatory rotation. The block-shaped contour piece 22 is preferably made of a cured rubber material, which adjoins the edge of the workpiece as seamless as possible or can be pressed. The contour piece 22 can either be screwed on or mechanically pressed or driven off.

The 14 shows a perspective enlarged top view of the top of an upper clamping plate 8d with two provided in the upper face sinks 8g . 8h for receiving the widened rope end terminals at the ends of the rope (without rope). The rope is over in the lateral surface of the cylindrical clamping plate 8d trained introduction slots 8i . 8j guided down to the opposite mounting plate.

The 15 shows a perspective view of a Entgratwerkzeugs with a transport device for clocked moving the rope, also not shown. This transport device comprises a top cap arranged 26 , one through this cap 26 Coverable cable reel 28 with a cylindrical rope wrapping area for wrapping with the rope. Preferably, the cable length is chosen to be the distance between two on the opposite mounting plates 8c . 8d lying pulleys 8f to bridge. This rope reel 28 indicates at her the cap 26 facing a radially opposite to the nominal diameter of the cable reel 28 enlarged pinion 30 on. For fixing the position of the rope on the rope reel 28 has these on the lateral surface at two diametrically opposite sides insertion eyelets 32 for attaching the rope terminals. The rope becomes after wrapping the rope coil 28 through openings in the middle of the cable reel down and laterally into the eyelets 32 introduced.

The 16 shows a perspective view of a deburring device 4 with an alternative cable transport device.

Between the over the drive axis of the servomotor 4s driven axis of rotation 8a the deburring device 8th is below the rotation with the axis of rotation 8a connected lower clamping plate 8c the rotatable on the axis of rotation 8a attached cable reel 28 arranged, which two radially radially projecting from the cylindrical bobbin cable holders 28a . 28b for the rope end connections (rope thimbles) of the rope 8b (not shown). That around this rope coil 28 and with the rope end connections in the rope mounts 28a . 28b used rope 8b is then attached to the side of the rotationally fixed to the axis of rotation, cylindrical cable guide element 33 3 times crossed at the pin 33a . 33b passed and on the pulleys 8f the mounting plate 8c . 8d guided, with a 2-fold crossing is also possible. Between the bottom of this cable reel 28 is a switch lever 35 the ratchet enclosing ratchet housing 34 formed, to which the cable reel 28 adjacent to the realization of a clocked rope circulation.

The subject matter of the present invention results not only from the subject matter of the individual claims, but also from the combination of the individual claims with one another. All information and features disclosed in the documents - including the abstract - in particular the spatial design shown in the drawings are claimed as essential to the invention, as far as they are new individually or in combination with respect to the prior art.

LIST OF REFERENCE NUMBERS

2

6-axis articulated robot

4

deburring

4a

servomotor

4b

suction funnel

4c

drive axle

4d

C-frame support

4e

splash guard

4f

Ionisiersprühdüse

4g

Ionisiersprühdüse

4h

suction

4i

suction

6

force sensor

8th

deburring

8a

axis of rotation

8b

rope

8c

(lower) mounting plate

8d

(upper) mounting plates

8e

Quick release

8f

idler pulley

8g

depression

8h

depression

8i

insertion slot

8j

insertion slot

10

Quick clamping device

10a

holder

10b

holding leg

10c

holding leg

12

central articulated robot

14

buff

16

buff

18

Entgratroboter

20

deburring

20a

axis of rotation

20b

hollow cylinder

20c

wear coat

22

contour piece

24

workpiece

24a

target contour

24b

edge

26

cap

28

cable reel

28a

cable holder

28b

cable holder

30

pinion

32

Einsatzöse

33

Rope guiding element

33a

spigot

33b

spigot

34

ratchet housing

35

Switching lever

36

ratchet

Claims (3)

Deburring tool ( 8th ) comprising a rotatable in a drive rotation axis ( 8a ), two spaced apart in the longitudinal direction at the rotational axis and spaced transversely extending therefrom ( 8c . 8d ) each having outer peripheral edges, of which at least one longitudinally displaceable on the axis of rotation ( 8a ), one between the mounting plates ( 8c . 8d ) arranged compression spring for realizing a defined bias between the mounting plates ( 8c . 8d ), and at least one between the mounting plates ( 8c . 8d Rope, which is marked on the mounting plates ( 8c . 8d ) Deflecting elements are provided, and that the rope is in one piece ( 8b ), which is formed around the deflection points between the mounting plates ( 8c . 8d ) extends, that the deflecting pulleys ( 8f ) and that the pulleys ( 8f ) Comprise brakes or position fixings for the rope ( 8b ) are provided. Deburring tool ( 8th ) according to claim 1, characterized in that the position fixing means comprise cable end connections, also termed terminals. Deburring tool ( 8th ) according to one of the preceding claims, characterized in that it comprises a quick-release device.

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