End effector with optimised tracking of a tool and method for machining a workpiece surface

Abstract

The invention relates to an end effector for attaching to a robotic or positioning device. The end effector comprises a first end effector sub-section having a fastener configured to be fastened to the robotic or positioning device. Furthermore, the end effector comprises at least one first pivot bearing, which is attached to the first end effector sub-section, and a second end effector sub-section, which is connected to the first end effector sub-section via the at least one first pivot bearing such that the second end effector sub-section can be pivoted relative to the first end effector sub-section about a first axis of rotation. The second end effector sub-section has a tool holder and a tool held by the tool holder, wherein the tool is designed to machine a surface of a workpiece. The at least one first pivot bearing is designed such that, when the end effector is placed on a workpiece, the first axis of rotation extends at the workpiece surface or on the side of the workpiece surface facing the workpiece at a distance of less than (10) mm from the workpiece surface or extends on the side of the workpiece surface facing away from the workpiece at a distance of less than (50) mm from the workpiece surface, in each case as viewed in the normal direction to the workpiece surface.

Description

[0001] End effector with optimized tracking of a tool and method for machining a workpiece surface

[0002] Description

[0003] Field of the invention

[0004] The invention relates to an end effector for attachment to a robot or positioning device. Furthermore, the invention relates to a machining device comprising a robot or positioning device and an end effector. Furthermore, the invention relates to a method for machining a workpiece surface using an end effector attached to a robot or positioning device.

[0005] Problem underlying the invention

[0006] It is an object of the invention to provide an end effector and a method for machining a workpiece surface by means of an end effector, which enables optimal tracking of a tool resting on a workpiece surface during machining of the workpiece surface.

[0007] Inventive solution

[0008] The stated object is achieved by an end effector for attachment to a robot or positioning device. The end effector comprises a first end effector section having a fastening element designed to be fastened to the robot or positioning device. In addition, the end effector comprises at least one first pivot bearing attached to the first end effector section, and a second end effector section connected to the first end effector section via the at least one first pivot bearing such that the second end effector section can be pivoted relative to the first end effector section about a first axis of rotation. The second end effector section has a tool holder and a tool held by the tool holder, wherein the tool is designed to machine a surface of a workpiece.The at least one first pivot bearing is designed such that, when the end effector is placed on a workpiece, the first axis of rotation runs on the workpiece surface or on the side of the workpiece surface facing the workpiece at a distance of less than 10 mm from the workpiece surface or on the side of the workpiece surface facing away from the workpiece at a distance of less than 50 mm from the workpiece surface, in each case viewed in the normal direction to the workpiece surface.

[0009] According to the embodiments of the present invention, the first axis of rotation, when the tool is placed on the workpiece, is positioned such that it is within a distance range from the workpiece surface. The distance between the first axis of rotation and the workpiece surface is to be understood in the normal direction to the workpiece surface. By arranging the first axis of rotation at a comparatively small distance from the workpiece surface, it is achieved in particular that the tool rests stably on the workpiece surface. When the tool is moved over the workpiece, tilting moments act on the tool as a result of the frictional force. Due to the comparatively small distance between the first axis of rotation and the workpiece surface, these tilting moments can be kept so small that tilting of the tool, which could, for example, lead to damage to the workpiece surface, can be avoided.By positioning the first rotation axis close to the workpiece surface, a stable tool support can be ensured, even when machining complex workpiece topologies at higher speeds. This makes it possible to achieve stable guidance of the tool over the workpiece when machining the workpiece surface, for example, during grinding.

[0010] The invention further relates to an end effector for attachment to a robot or positioning device. The end effector comprises a first end effector section having a fastening element designed to be attached to the robot or positioning device. Furthermore, the end effector comprises at least one first pivot bearing attached to the first end effector section, and a second end effector section connected to the first end effector section via the at least one first pivot bearing such that the second end effector section is pivotable relative to the first end effector section about a first axis of rotation. The second end effector section has a tool holder and a tool held by the tool holder, wherein the tool is designed to machine a surface of a workpiece.The at least one first pivot bearing comprises at least one segmented rolling bearing or at least one segmented plain bearing.

[0011] The design of the first pivot bearings as segmented roller bearings or segmented plain bearings has the particular advantage that the position of the first rotational axis can be determined by the respective geometric design of the segmented roller bearings or segmented plain bearings. For example, the position of the first rotational axis, about which the second section can be pivoted relative to the first section, depends, for example, on the radius of the roller or plain bearing guides. Therefore, the use of segmented roller bearings or segmented plain bearings makes it possible, for example, to move the first rotational axis close to the workpiece surface to enable stable guidance of the tool on the workpiece surface.

[0012] The invention further relates to an end effector for attachment to a robot or positioning device, in particular to a robot arm. The end effector comprises a first end effector section having a fastening element designed to be attached to the robot or positioning device, in particular to the robot arm. Furthermore, the end effector comprises at least one first pivot bearing attached to the first end effector section, as well as an end effector center section connected to the first end effector section via the at least one first pivot bearing such that the end effector center section is pivotable relative to the first end effector section about a first axis of rotation.Furthermore, the end effector comprises at least one second pivot bearing mounted on the end effector center section, as well as an end effector end section connected to the end effector center section via the at least one second pivot bearing such that the end effector end section is pivotable relative to the end effector center section about a second rotation axis. The end effector end section has a tool holder and a tool held by the tool holder, wherein the tool is configured for machining a surface of a workpiece.The at least one first pivot bearing is designed such that, when the end effector is placed on a workpiece, the first axis of rotation runs on the workpiece surface or on the side of the workpiece surface facing the workpiece at a distance of less than 10 mm from the workpiece surface or on the side of the workpiece surface facing away from the workpiece at a distance of less than 50 mm from the workpiece surface, in each case viewed in the normal direction to the workpiece surface.The at least one second pivot bearing is designed such that, when the end effector is placed on the workpiece, the second axis of rotation runs on the workpiece surface or on the side of the workpiece surface facing the workpiece at a distance of less than 10 mm from the workpiece surface or on the side of the workpiece surface facing away from the workpiece at a distance of less than 50 mm from the workpiece surface, in each case viewed in the normal direction to the workpiece surface.

[0013] The invention also relates to a processing device comprising a robot or positioning device and an end effector as described above, wherein the end effector is attached to the robot or positioning device by means of the fastening element.

[0014] The invention further relates to a method for machining a workpiece surface using an end effector that is attached to a robot or positioning device. The end effector comprises a first end effector section having a fastening element with which the end effector is attached to the robot or positioning device. Furthermore, the end effector comprises at least one first pivot bearing attached to the first end effector section, and a second end effector section that is connected to the first end effector section via the at least one first pivot bearing such that the second end effector section is pivotable relative to the first end effector section about a first axis of rotation. The second end effector section has a tool holder and a tool held by the tool holder, wherein the tool is designed to machine a surface of a workpiece.The method comprises placing the end effector on a workpiece surface. When the end effector is placed on the workpiece, the first axis of rotation runs on the workpiece surface or on the side of the workpiece surface facing the workpiece at a distance of less than 10 mm from the workpiece surface or on the side of the workpiece surface facing away from the workpiece at a distance of less than 50 mm from the workpiece surface, in each case viewed in the normal direction to the workpiece surface, wherein the orientation of the tool holder and the tool automatically adapts to the workpiece surface by pivoting the second end effector section about the first axis of rotation. Preferred embodiments of the invention.

[0015] Advantageous training and further developments, which can be used individually or in combination with one another, are the subject of the dependent claims and the following description.

[0016] Preferably, the at least one first pivot bearing is designed such that the first axis of rotation on the side of the workpiece surface facing the tool runs at a distance of less than 7 mm, more preferably less than 5 mm, more preferably less than 3 mm, more preferably less than 2 mm, more preferably less than 1 mm, more preferably less than 0.5 mm from the workpiece surface.

[0017] Further preferably, the at least one first pivot bearing is designed such that the first axis of rotation on the side of the workpiece surface facing away from the tool runs at a distance of less than 50 mm, further preferably less than 30 mm, further preferably less than 20 mm, further preferably less than 10 mm, further preferably less than 7 mm, further preferably less than 5 mm, further preferably less than 3 mm, further preferably less than 2 mm, further preferably less than 1 mm from the workpiece surface.

[0018] According to an advantageous embodiment, the at least one first pivot bearing is designed such that, when the end effector is placed on a workpiece, the distance between the first axis of rotation and the workpiece surface, viewed in the normal direction to the workpiece surface, is less than a quarter of the smallest lateral extent of the effective machining surface of the tool intended for machining the workpiece surface.

[0019] According to an advantageous embodiment, the at least one first pivot bearing comprises at least one segmented rolling bearing or at least one segmented sliding bearing.

[0020] Preferably, each first pivot bearing is designed as a segmented roller bearing or a segmented plain bearing. It is advantageous if the at least one first pivot bearing is designed such that the first rotation axis extends outside the tool holder.

[0021] Preferably, the second end effector section comprises:

[0022] - an end effector center section, which is connected to the first end effector section via the at least one first pivot bearing such that the end effector center section (and thus the entire second end effector section) can be pivoted relative to the first end effector section about the first axis of rotation,

[0023] - at least one second pivot bearing mounted on the end effector center section,

[0024] - an end effector end section which is connected to the end effector center section via the at least one second pivot bearing such that the end effector end section is pivotable relative to the end effector center section about a second rotation axis, wherein the end effector end section comprises the tool holder and the tool,

[0025] - wherein the at least one second pivot bearing is designed such that, when the end effector is placed on the workpiece, the second axis of rotation runs on the workpiece surface or on the side of the workpiece surface facing the workpiece at a distance of less than 10 mm from the workpiece surface or runs on the side of the workpiece surface facing away from the workpiece at a distance of less than 50 mm from the workpiece surface, in each case viewed in the normal direction to the workpiece surface.

[0026] It is advantageous if the at least one second pivot bearing is designed such that the second axis of rotation on the side of the workpiece surface facing the tool runs at a distance of less than 7 mm, more preferably less than 5 mm, more preferably less than 3 mm, more preferably less than 2 mm, more preferably less than 1 mm, more preferably less than 0.5 mm from the workpiece surface.

[0027] Preferably, the at least one second pivot bearing is designed such that the second axis of rotation on the side of the workpiece surface facing away from the tool runs at a distance of less than 50 mm, more preferably less than 30 mm, more preferably less than 20 mm, more preferably less than 10 mm, more preferably less than 7 mm, more preferably less than 5 mm, more preferably less than 3 mm, more preferably less than 2 mm, more preferably less than 1 mm from the workpiece surface.According to an advantageous embodiment, the at least one second pivot bearing is designed such that, when the end effector is placed on a workpiece, the distance between the second axis of rotation and the workpiece surface, viewed in the normal direction to the workpiece surface, is less than a quarter of the smallest lateral extent of the effective machining surface of the tool intended for machining the workpiece surface.

[0028] Preferably, the at least one second pivot bearing comprises at least one segmented rolling bearing or at least one segmented plain bearing.

[0029] It is advantageous if each of the second pivot bearings is designed as a segmented rolling bearing or as a segmented plain bearing.

[0030] Preferably, the at least one second pivot bearing is designed such that the second axis of rotation runs outside the tool holder.

[0031] According to an advantageous embodiment, the second axis of rotation runs, viewed in the normal direction to the workpiece surface, at an angle in the range of 50° to 130°, more preferably at an angle between 80° and 100°, more preferably approximately at a right angle to the first axis of rotation.

[0032] Preferably, the second axis of rotation intersects the first axis of rotation.

[0033] Preferably, the second axis of rotation intersects the first axis of rotation at a pole.

[0034] Preferably, the tool is an active tool or a passive tool.

[0035] Preferably, the tool is an active tool, in particular one of the following: rotary sander, eccentric sander, orbital sander, belt sander, or polisher. According to an advantageous embodiment, the tool is a passive tool, in particular one of the following: a grinding stone, a sanding block covered with sandpaper, or a honing stone.

[0036] According to an advantageous embodiment, the tool is designed for machining with an indeterminate cutting edge.

[0037] Preferably, the tool is a grindstone or the tool comprises a grindstone.

[0038] It is advantageous if the grindstone is essentially cuboid-shaped.

[0039] Preferably, the grindstone has a smallest lateral dimension of more than 1 mm, more preferably more than 5 mm, more preferably more than 10 mm.

[0040] Preferably, the grindstone has a largest lateral dimension of less than 50 mm, more preferably less than 40 mm, more preferably less than 30 mm.

[0041] Further preferably, the grindstone has a longitudinal extent of more than 1 mm, further preferably of more than 5 mm, further preferably of more than 10 mm.

[0042] Further preferably, the grindstone has a longitudinal extent of less than 200 mm, further preferably less than 150 mm, further preferably less than 130 mm.

[0043] It is advantageous if the end effector is designed so that when the tool holder and the tool are placed on the workpiece surface, the tool holder and the tool align themselves automatically relative to the workpiece surface.

[0044] According to an advantageous embodiment, the at least one first pivot bearing comprises a pair of segmented roller bearings or segmented plain bearings arranged opposite one another in a mirror-symmetrical manner. Preferably, the at least one first pivot bearing comprises a pair of segmented roller bearings or segmented plain bearings arranged opposite one another in a mirror-symmetrical manner, forming an adjusted bearing arrangement.

[0045] Preferably, the at least one first pivot bearing is designed to be pivoted about the first axis of rotation by a predetermined angular range.

[0046] According to an advantageous embodiment, the end effector has at least one spring element which is designed to return the tool holder with the tool to a home position by means of spring force when the end effector is not resting on a workpiece surface.

[0047] Preferably, the end effector is designed to be detachably attached to the robot or positioning device by means of the fastening element.

[0048] Preferably, the first end effector section comprises at least one intermediate member.

[0049] Preferably, the second end effector section comprises at least one intermediate member.

[0050] Preferably, the second end effector section has an end effector center section which comprises at least one intermediate member.

[0051] Preferably, the second end effector section has an end effector end section comprising at least one intermediate member.

[0052] According to an advantageous embodiment, the intermediate member comprises at least one of the following:

[0053] - a translational adjustment device;

[0054] - a wing;

[0055] - a damping device.

[0056] Preferably, the intermediate member comprises a translational adjustment device, wherein the translational adjustment device comprises at least one of the following:

[0057] - a pneumatic cylinder;

[0058] - a hydraulic cylinder; - an electric linear actuator;

[0059] - a linear guide.

[0060] According to an advantageous embodiment, the intermediate member comprises a translatory adjusting device which is designed to press the tool against the workpiece surface with a predetermined contact force or predetermined contact pressure.

[0061] It is advantageous if the translational adjustment device comprises a pressure sensor for detecting the contact pressure with which the tool is pressed against the workpiece surface.

[0062] Preferably, the translational adjustment device comprises a control system which is designed to regulate the contact pressure to a predetermined target value.

[0063] According to an advantageous embodiment, the translational adjustment device comprises a force sensor for detecting the contact force with which the tool is pressed against the workpiece surface.

[0064] Preferably, the translational adjustment device comprises a control system which is designed to regulate the contact pressure to a predetermined target value.

[0065] According to an advantageous embodiment, the robot or positioning device comprises a robot flange, wherein the end effector is attached to the robot flange by means of the fastening element.

[0066] Preferably, the robot or positioning device comprises a robot arm to which the end effector is attached by means of the fastening element.

[0067] According to an advantageous embodiment, the second end effector section comprises:

[0068] - an end effector center section, which is connected to the first end effector section via the at least one first pivot bearing such that the end effector center section (and thus the entire second end effector section) can be pivoted relative to the first end effector section about the first axis of rotation,

[0069] - at least one second pivot bearing mounted on the end effector center section, - an end effector end section connected to the end effector center section via the at least one second pivot bearing such that the end effector end section is pivotable relative to the end effector center section about a second rotation axis, wherein the end effector end section comprises the tool holder and the tool,

[0070] - wherein the at least one second pivot bearing comprises at least one segmented rolling bearing or at least one segmented plain bearing.

[0071] Brief description of the drawings

[0072] Further advantageous embodiments are described in more detail below with reference to several exemplary embodiments shown in the drawings, to which the invention is not limited, however.

[0073] It shows schematically:

[0074] Figure 1 shows an embodiment of an end effector with a tool that can be pivoted about two axes of rotation;

[0075] Figure 2 shows a further embodiment of an end effector with a tool pivotable about a rotation axis;

[0076] Figure 3 shows a detailed view of an end effector;

[0077] Figure 4 shows a robot device to whose robot flange an end effector can be attached;

[0078] Figure 5 shows an oblique view of a segment ball bearing;

[0079] Figure 6A shows a cross-section through a segment ball bearing designed as a deep groove ball bearing;

[0080] Figure 6B shows a cross-section through a segment ball bearing whose outer and inner segments have square guide grooves; Figure 6C shows a cross-section through a segment ball bearing designed as an angular contact ball bearing;

[0081] Figure 7 shows a schematic representation of an adjusted bearing arrangement comprising two angular contact ball bearings axially clamped against each other;

[0082] Figure 8A shows a side view of the tool holder with the tool, with the rotation axis of the pivot bearing arranged above the workpiece surface;

[0083] Figure 8B shows a side view of the tool holder with the tool, wherein the rotation axis of the pivot bearing is arranged on the workpiece surface;

[0084] Figure 8C shows a side view of the tool holder with the tool, with the rotation axis of the pivot bearing arranged below the workpiece surface;

[0085] Figure 9A shows an embodiment of an end effector whose first end effector section comprises an intermediate member;

[0086] Figure 9B shows an embodiment of an end effector whose end effector center section comprises an intermediate member; and

[0087] Figure 9C shows an embodiment of an end effector whose end effector end section comprises an intermediate member.

[0088] Detailed description of embodiments of the invention

[0089] In the following description of preferred embodiments of the present invention, like reference numerals designate like or comparable components.

[0090] Figure 1 schematically illustrates the structure of an end effector 2 according to a first exemplary embodiment. The end effector 2 is designed to be attached to a robot or positioning device. For this purpose, the end effector 2 comprises a fastening element 4, with which the end effector 2 can be fastened, for example, to a robot flange of the robot or positioning device, for example to the robot flange of a robot arm. The end effector 2 is used to machine the surface of a workpiece, for example to grind or polish the workpiece. The workpiece can be, for example, a body part of a vehicle, but also a pressing tool or an injection molding tool, whereby the desired surface quality is achieved through grinding.

[0091] The end effector 2 according to the first embodiment of the invention comprises a first end effector section 6, which can be attached to the robot flange of the robot or positioning device via the fastening element 4 belonging to the first end effector section 6. In addition, the end effector 2 comprises a pair of first pivot bearings 8, 10 and a second end effector section 12. The first pivot bearing 10, which is concealed by the end effector, is shown in dashed lines in Figure 1. The second end effector section 12 is pivotally connected to the first end effector section 6 via the first pivot bearings 8, 10. The second end effector section 12 can be pivoted relative to the first end effector section 6 about a first rotation axis 14, as illustrated in Figure 1 by the double arrow 15.The first rotation axis 14 runs, as shown in Figure 1, along the workpiece surface or at a short distance from the workpiece surface. The first pivot bearings 8, 10 can be designed, for example, as segmented roller bearings or as segmented plain bearings.

[0092] The second end effector section 12, in turn, comprises an end effector center section 16, a pair of second pivot bearings 18, 20, and an end effector end section 22. The end effector end section 22 is pivotally connected to the end effector center section 16 via the two second pivot bearings 18, 20, wherein the end effector end section 22 can be pivoted relative to the end effector center section 16 about a second axis of rotation 24, as illustrated in Figure 1 by the double arrow 25. The second pivot bearings 18, 20 can also be designed as segmented roller bearings or segmented plain bearings. The two second pivot bearings 18, 20 are arranged at a right angle relative to the first pivot bearings 8, 10, so that the second axis of rotation 24 runs essentially at a right angle to the first axis of rotation 14. The second rotation axis 24 also runs on the surface of the workpiece or at a short distance from the surface of the workpiece.The end effector end section 22 comprises a tool holder 26 and a tool 28 held in the tool holder 26, which is designed to machine the workpiece surface. A passive tool can be used to machine the surface of the workpiece, for example a grindstone, a sanding block covered with sandpaper, or a honing stone that is guided over the surface of the workpiece by the robot or positioning device. Alternatively, an active tool can be used, in particular a tool driven by a motor, for example a rotary sander, an eccentric sander, an orbital sander, a belt sander, a polisher, etc. In the example shown in Figure 1, the tool holder 26 is designed as a grindstone clamping device, in which a grindstone is clamped as the tool 28.

[0093] When the end effector 2 is moved towards the surface of the workpiece to be machined, the tool 28 clamped in the tool holder 26 is placed onto the workpiece surface. Since the tool 28 can be pivoted about both the first rotation axis 14 and the second rotation axis 24, the angular position of the tool 28 automatically adapts to the workpiece surface to be machined, so that the underside of the tool 28 rests optimally on the respective support area of ​​the workpiece surface. As a result of this automatic alignment of the angular position of the tool 28 depending on the topology of the workpiece surface when the end effector 2 is pressed against the workpiece, tilting of the tool 28 relative to the workpiece surface is prevented, so that damage to the workpiece surface caused by a tilted tool 28 can be avoided.When the tool 28 is then guided over the workpiece surface by the robot or positioning device, the angular position of the end effector adapts dynamically to the topology of the respective support area.

[0094] Figure 2 schematically shows an end effector 30 according to a second exemplary embodiment, the second exemplary embodiment being significantly simplified compared to the first exemplary embodiment shown in Figure 1. The end effector 30 according to the second exemplary embodiment comprises a first end effector section 32 with a fastening element 34 with which the end effector 30 can be fastened to a robot or positioning device. In addition, the end effector 30 comprises a pair of first pivot bearings 36, 38 and a second end effector section 40. The first pivot bearing 38, which is concealed by the end effector, is shown in dashed lines in Figure 2. The second end effector section 40 is pivotally connected to the first end effector section 32 via the first pivot bearings 36, 38.The second end effector section 40 can be pivoted relative to the first end effector section 32 about a first rotation axis 42, as illustrated in Figure 2 by the double arrow 43. The first pivot bearings 36, 38 can again be designed as segmented roller bearings or as segmented plain bearings. The second end effector section 40 comprises a tool holder 44 and a tool 46 held in the tool holder 44. In the example shown in Figure 2, the tool holder 44 is designed as a grindstone clamping device, in which a grindstone is clamped as the tool 46.

[0095] Figure 3 shows a detailed illustration of an end effector 48 according to the first embodiment of the invention. Therefore, the reference numerals introduced in the description of the end effector 2 according to the first embodiment are used in the description of Figure 3.

[0096] The end effector 48 shown in Figure 3 comprises a first end effector section 6, which is fastened to a member 50 of a robot arm via the fastening element 4. As can be seen in Figure 3, the first end effector section 6 comprises a translational adjustment device 52, which is designed to generate a translational movement of the tool 28 relative to the member 50 of the robot arm. For this purpose, the translational adjustment device 52 can, for example, comprise a cylinder and a guide for a translational movement. The translational movement that can be generated by the translational adjustment device 52 is illustrated in Figure 3 by the double arrow 54. The cylinder can, for example, be a pneumatic cylinder.

[0097] The first end effector section 6 is pivotally connected to the end effector center section 16 via the pair of first pivot bearings 8, 10, whereby only the first pivot bearing 8 can be seen in Figure 3. The first pivot bearings 8, 10 enable the end effector center section 16 to pivot relative to the first end effector section 6 about the first axis of rotation 14. The first pivot bearings 8, 10 can be designed, for example, in the form of segment ball bearings. In Figure 3, the first pivot bearing 8 is shown in a partially broken away view. The end effector center section 16 is pivotally connected to the end effector end section 22 via the pair of second pivot bearings 18, 20, whereby only the second pivot bearing 18 can be seen in Figure 3. By means of the second pivot bearings 18, 20, the end effector end section 22 can be pivoted relative to the end effector center section 16 about the second rotation axis 24.The second pivot bearings 18, 20 can also be designed, for example, as segmented ball bearings. Figure 3 shows the second pivot bearing 18 in a partially cutaway view. The end effector end section 22 comprises the tool holder 26 and the tool 28 held in the tool holder 26. In the embodiment shown in Figure 3, a grindstone is used as the tool 28, which is clamped in the tool holder 26, which is designed as a grindstone clamping device.

[0098] In the end effector 48 shown in Figure 3, the first pivot bearings 8, 10 are configured orthogonally to the second pivot bearings 18, 20. Therefore, viewed in the normal direction to the support surface of the tool 28 on the workpiece, the first axis of rotation 14 is arranged at a right angle to the second axis of rotation 24. The first pivot bearings 8, 10 and the second pivot bearings 18, 20 are configured such that the first axis of rotation 14 and the second axis of rotation 24 lie on or near the workpiece surface. The arrangement of the axes of rotation 14, 24 in the workpiece surface or at a short distance from the workpiece surface offers the advantage that the tilting moments acting on the tool 28 can be kept low or completely avoided. In the embodiment shown in Figure 3, the first pivot bearings 8, 10 and the second pivot bearings 18, 20 are designed such that the first axis of rotation 14 intersects the second axis of rotation 24.In this case, a pole 56, also referred to as the instantaneous pole, is created at the intersection of the two rotational axes 14 and 24. As an alternative to the embodiment of the end effector 48 shown in Figure 3, embodiments with non-intersecting rotational axes may also be useful. The rotational axes should always be located at or near the workpiece surface to avoid large tilting moments acting on the tool 28.

[0099] The end effector 48 shown in Figure 3 is provided with springs 58 which are designed to hold the joint mechanism in a central position when the tool 28 is not placed on the workpiece. For example, the first end of the spring 58 can be attached to the first end effector section 6, while the second end of the spring 58 is attached to the end effector end section 22. To hold the joint mechanism in the central position, a total of two to four springs can be provided, for example. Furthermore, Figure 3 shows an extraction device which comprises an extraction nozzle 60 arranged near the grinding dust generation, preferably in front of and behind the tool 28, as well as an extraction hose 62 for extracting grinding dust. The extraction hose 62 can in particular be designed as a corrugated hose.Preferably, both the extraction nozzle 60 and the extraction hose 62 for extracting grinding dust are arranged within a dust protection sleeve 64, which encapsulates the dirt-sensitive system, in particular the first pivot bearings 8, 10 and the second pivot bearings 18, 20, from the outside. The upper end of the dust protection sleeve 64 can be fastened, for example, to the fastening element 4 or to the first end effector section 6, while the lower end of the dust protection sleeve 64 can be attached to the end effector end section 22. Preferably, the extraction nozzle 60 and the extraction hose 62 of the extraction device are arranged within the dust protection sleeve 64 in order to keep the environmental exposure to grinding dust as low as possible. The interior of the dust protection sleeve 64 is preferably ventilated via a filter element.

[0100] Figure 4 shows a robot device 66 to which an end effector, in particular an end effector according to one of the previously described embodiments, can be attached. The robot device 66 comprises a platform 68, a plurality of links 70a to 70g, a robot flange 72, and joints 74. The links 70a to 70g and the robot flange 72 are connected to one another via the joints 74. The robot flange 72 is articulated to the last link 70g. An end effector according to one of the previously described embodiments can be attached to the robot flange 72 by means of its fastening element, for example by means of one or more screw connections. For example, the end effector 48 shown in Figure 3 can be attached to the robot flange 72 by means of its fastening element 4.By means of the robot device 66, the tool 28 clamped in the end effector 48 can then be guided over the workpiece surface according to predeterminable machining trajectories.

[0101] The pivot bearings described so far can be designed, for example, as segmented ball bearings. Figure 5 shows an embodiment of such a segmented ball bearing 76. The segmented ball bearing 76 comprises an inner segment 78 and an outer segment 80, which can be pivoted relative to the inner segment 78 within a predetermined pivot angle range about the rotation axis 82. Between the inner segment 78 and the outer segment 80, a plurality of balls 84 are provided, which are rotatably mounted in a ball cage 86.

[0102] Figure 6A shows a first embodiment of the segment ball bearing 76 in cross-section. The balls 84 and the ball cage 86 can be seen in Figure 6A. The profile of the inner segment 78 has a round groove 88 for guiding the balls 84. The outer segment 80 of the segment ball bearing 76 also has a round groove 90 for receiving and guiding the balls 84.

[0103] Figure 6B shows an alternative embodiment of the segment ball bearing 76 in cross-section. In contrast to the embodiment shown in Figure 6A, the profile of the inner segment 78 has a groove 92 with inclined guide surfaces. The profile of the outer segment 80 also has a square groove 94 with inclined guide surfaces for the balls 84.

[0104] Figure 6C shows a further embodiment of the segment ball bearing 76 in cross-section, wherein the segment ball bearing 76 is designed here as an angular contact ball bearing. In such an angular contact ball bearing, both the end face 95 of the inner segment 78 and the end face 96 of the outer segment 80 are tilted by an angle α relative to the vertical, resulting in a parallel arrangement of the two inclined end faces 95 and 96. The profile of the inner segment 78 has a round groove 98 for guiding the balls 84. The outer segment 80 of the segment ball bearing 76 also has a round groove 99 for receiving and guiding the balls 84. Such angular contact ball bearings are particularly suitable for absorbing axial forces in addition to radial forces. A force flow line 100 of the angular contact ball bearing is also shown in Figure 6C.

[0105] Angular contact ball bearings or, more generally, angular contact roller bearings of the type shown in Figure 6C are particularly suitable for the implementation of a so-called adjusted bearing arrangement. Such an adjusted bearing arrangement is shown schematically in Figure 7. An adjusted bearing arrangement is generally formed from two angular contact bearings arranged in a mirror image of one another, whereby, for example, angular contact ball bearings, tapered roller bearings, or deep groove ball bearings can be used. The adjusted bearing arrangement shown in Figure 7 comprises two angular contact ball bearings 102-1, 102-2 arranged in a mirror-symmetrical manner to one another. Each of the two angular contact ball bearings 102-1, 102-2 comprises an inner segment 104-1 or 104-2, an outer segment 106-1 or 106-2, balls 108-1 or 108-2, and a ball cage 110-1 or 110-2. The inner segments 104-1 and 104-2 are mechanically firmly connected to the first support unit 112. A clamping element 116 is attached to the second support unit 114 by means of at least one screw connection 115.By screwing the clamping element 116 to the second carrier unit 114, the outer segments 106-1 and 106-2 of the two angular contact ball bearings 102-1, 102-2 are clamped and thereby mechanically firmly connected to the second carrier unit 114. This enables pivoting of the second carrier unit 114 relative to the first carrier unit 112. By screwing the clamping element 116 to the second carrier unit 114, the two outer segments 106-1 and 106-2 of the angular contact ball bearings 102-1, 102-2 are each subjected to an inwardly directed axial preload force 117-1 and 117-2, respectively. The process of applying these preload forces 117-1, 117-2 is referred to as "adjusting," hence the term "adjusted bearing."

[0106] Let us now assume that a force 118 acts on the first support unit 112. In an end effector of the type described so far, such an upward force 118 acts on the respective bearings, for example, as a result of the tool being pressed against the workpiece. The force is transmitted from the inner segments 104-1, 104-2 according to the dashed force flow lines 120-1 and 120-2 to the outer segments 106-1, 106-2 and absorbed by the second support unit 114.

[0107] With adjusted bearings, the play of the two angular contact ball bearings 102-1 and 102-2 can be regulated and, in particular, reduced by appropriately adjusting the axial preload forces 117-1 and 117-2. Adjusted bearings are therefore particularly suitable when precise guidance is required. It is therefore advantageous to implement the pairs of oppositely arranged pivot bearings used in the end effector embodiments discussed so far using adjusted bearings, because this allows precise and play-free guidance of the tool 28 or 46. In particular, the pair of first pivot bearings 8, 10, which enables pivoting of the second end effector section 12 relative to the first end effector section 6, can preferably be implemented in the form of an adjusted bearing.Alternatively or additionally, the pair of second pivot bearings 18, 20, which enables pivoting of the end effector end section 22 relative to the end effector center section 16, can also be implemented in the form of an adjusted bearing.

[0108] In the second embodiment shown in Figure 2, the pivot bearings 36, 38 can also be implemented in the form of an adjusted bearing. The segment bearings can be designed, for example, as angular contact ball bearings, tapered roller bearings, or deep groove ball bearings.

[0109] Figures 8A to 8C show various ways in which a rotational axis of the tool can be positioned relative to the workpiece surface. For this purpose, Figures 8A to 8C each show a side view of the tool 28 clamped in the tool holder 26, wherein the tool 28 is preferably a grindstone for grinding the workpiece surface 122. The tool holder 26 is part of an end effector according to one of the embodiments described so far and can be pivoted about the rotational axis 82 by means of the segment ball bearing 76. The cut-away view of the segment ball bearing 76 shows the inner segment 78, the outer segment 80, the balls 84 and the ball cage 86. The double arrow 124 illustrates how the tool holder 26 with the tool 28 can be pivoted about the rotational axis 82.

[0110] The rotation axis 82 is shown in Figures 8A, 8B, and 8C in three different positions relative to the workpiece surface 122. In Figure 8A, the rotation axis is arranged on the side of the workpiece surface 122 facing the tool 28 at a distance a>0 from the workpiece surface 122. In Figure 8B, the rotation axis 82 is arranged on the workpiece surface 122, and in Figure 8C, the rotation axis 82 is arranged on the side of the workpiece facing away from the workpiece surface 122 at a distance a from the workpiece surface 122, wherein the distance a in this case is negative according to the sign convention used here.

[0111] In all cases shown, the tool 28 rests with its machining surface 126 on the workpiece surface 122. The width b of the machining surface 126 is shown in Figures 8A to 8C. By appropriately controlling the robot device 66, the tool holder 26 with the tool 28 is guided in a direction of movement 128 over the workpiece surface 122. In doing so, the tool 28 is pressed against the workpiece surface 122 with a predetermined contact force or a predetermined contact pressure.

[0112] As a result of the tool 28 being pressed against the workpiece surface 122, an upwardly directed normal force 130 acts on the machining surface 126 of the tool 28. The frictional force 132, which acts on the tool 28 in a direction opposite to the direction of movement 128, is proportional to this normal force 130. The frictional force 132 creates a tilting moment M=a*FR acting on the tool 28 in a counterclockwise direction, the magnitude of which depends on the distance a of the rotational axis 82 from the workpiece surface 122. This tilting moment M should, if possible, be kept as small as possible to prevent tilting of the tool 28. Therefore, according to embodiments of the present invention, it is provided to keep the distance a between the rotational axis 82 and the workpiece surface 122 small.

[0113] Preferably, the first rotation axis 82 is arranged on the side of the workpiece surface 122 facing the workpiece at a distance from the workpiece surface 122 of less than 10 mm, more preferably less than 7 mm, more preferably less than 5 mm, more preferably less than 3 mm, more preferably less than 2 mm, more preferably less than 1 mm, more preferably less than 0.5 mm. The distance of the first rotation axis 82 from the workpiece surface 122 is considered in the normal direction to the workpiece surface 122.

[0114] According to a further criterion, the distance a between the rotation axis 82 and the workpiece surface 122 in the normal direction to the workpiece surface 122 should preferably be less than a quarter of the smallest lateral extent of the machining surface 126 of the tool 28. In the example shown in Figures 8A to 8C, the length of the tool 28 is greater than the width b of the tool 28, so that the width b is the smallest lateral extent of the machining surface 126. The distance a of the rotation axis 82 to the workpiece surface 122 should therefore be less than a quarter of the width b.

[0115] Due to the small distance a between the rotation axis 82 and the workpiece surface 122, the tool 28 can be guided stably over the workpiece surface 122 and adapt to the topology of the workpiece surface 122 without tilting. In the case shown in Figure 8B, the rotation axis 82 runs directly along the workpiece surface 122, so that the resulting tilting moment M=FR*a is zero or at least approximately zero. In the case shown in Figure 8B, there is therefore no risk of the tool 28 tilting.

[0116] In the case shown in Figure 8C, the rotation axis 82 is arranged on the side of the workpiece surface 122 facing away from the tool 28, wherein the distance a between the rotation axis 82 and the workpiece surface 122 is less than zero according to the sign convention used here. In the case shown in Figure 8C, too, a frictional force 132 directed opposite to the direction of movement 128 arises as a result of the tool 28 being pressed against the workpiece surface 122. Since the rotation axis 82 is located below the workpiece surface 122, the frictional force 132 exerts a clockwise torque M=a*FR on the tool 28. This tilting moment M should, if possible, be kept as low as possible to prevent tilting of the tool 28. To prevent tilting of the tool 28, the rotation axis 82 should therefore also be positioned at the shortest possible distance from the workpiece surface 122.

[0117] Preferably, the first rotation axis 82 is arranged on the side of the workpiece surface 122 facing away from the workpiece at a distance from the workpiece surface 122 of less than 50 mm, more preferably less than 30 mm, more preferably less than 20 mm, more preferably less than 10 mm, more preferably less than 7 mm, more preferably less than 5 mm, more preferably less than 3 mm. The distance of the first rotation axis 82 from the workpiece surface 122 is considered in the normal direction to the workpiece surface 122.

[0118] According to a further criterion, the distance between the rotation axis 82 and the workpiece surface 122, viewed in the normal direction to the workpiece surface 122, should preferably be less than a quarter of the smallest lateral extent of the machining surface 126 of the tool 28. In the example shown in Figure 8C, the distance between the rotation axis 82 and the workpiece surface 122 should therefore be less than a quarter of the width b, since the width b represents the smallest lateral extent of the machining surface 126. Preferably, the segment ball bearing 76 is suitably designed to achieve positioning of the rotation axis 82 at a short distance from the workpiece surface 122. In particular, the segment ball bearing 76 can, for example, have a suitably curved ball guide in order to ensure that the rotation axis 82 runs at a short distance from the workpiece surface 122.

[0119] Figures 9A to 9C show three further embodiments of end effectors. The end effector 134 shown in Figure 9A comprises the first end effector section 6 with the fastening element 4 and the second end effector section 12, which is pivotally connected to the first end effector section 6 via the first pivot bearings 8, 10. The first pivot bearing 10, which is concealed by the end effector, is shown in dashed lines in Figure 9A. The second end effector section 12 comprises the end effector center section 16 and the end effector end section 22, which is pivotally connected to the end effector center section 16 via the second pivot bearings 18, 20. The end effector end section 22 comprises the tool holder 26 and the tool 28 held in the tool holder 28, wherein the tool 28 may be, for example, a grindstone.As a result of the described design of the end effector 134, the tool 28 can be pivoted about the first rotation axis 14 and about the second rotation axis 24 and thus adapt to the topology of the workpiece surface 122.

[0120] In the embodiment shown in Figure 9A, the first end effector section 6 has a first intermediate member 136. The first intermediate member 136 can, for example, comprise a translational adjustment device designed to move the tool holder 26 with the tool 28 in the axial direction away from the fastening element 4 or towards the fastening element 4. For this purpose, the translational adjustment device can, for example, comprise a cylinder, for example a pneumatic or hydraulic cylinder, and a guide device, as already shown in Figure 3. Such a translational adjustment device can, in particular, be designed to press the tool 28 against the surface of a workpiece. Preferably, the tool 28 is pressed by the translational adjustment device in the normal direction to the workpiece against the workpiece surface 122 with a predeterminable contact pressure or a predeterminable contact force.The translational adjustment device can, for example, comprise a force sensor or a pressure sensor designed to detect the contact pressure or contact force with which the tool 28 is pressed against the workpiece surface 122. Furthermore, the translational adjustment device can comprise a control system that adjusts the contact pressure or contact force with which the tool 28 is pressed against the workpiece surface 122 to a predetermined target value.

[0121] Alternatively or additionally, the first intermediate member 136 may comprise a two-armed rocker, wherein the first rocker arm of the rocker is rigidly connected to the upper part 138 of the first end effector section 6, and the second rocker arm is mechanically rigidly connected to the lower part 140 of the first end effector section 6. The two rocker arms of the rocker are connected via a pivot axis that extends transversely to the axial direction of the end effector 134, i.e., in the horizontal direction in Figure 9A. Just like the translational adjustment device described above, such a rocker also enables adjustment of the longitudinal position of the tool 28 relative to the fastening element 4.

[0122] Furthermore, the first intermediate member 136 shown in Figure 9A can comprise a damping device. Such a damping device can be provided to dampen vibrations arising during the movement of the tool 28 along the workpiece surface 122. For this purpose, the damping device can comprise, for example, a spring element and a shock absorber, for example a hydraulic damper, to dampen the vibrations that occur.

[0123] The first intermediate member 136 may comprise the three units described above, i.e. a translatory adjustment device, a rocker and a damping device, in any combination.

[0124] Figure 9B shows a further embodiment of an end effector 142, in which the end effector center section 16 has a second intermediate member 144. For a description of the various components of the end effector 142, reference is made to Figure 9A. The second intermediate member 144 can comprise a translatory adjustment device. The translatory adjustment device can, in particular, have a control system with which the contact pressure or the contact force of the tool 28 against the workpiece can be set to a predetermined target value. The second intermediate member 144 can also comprise a rocker as described above. Furthermore, the second intermediate member 144 can comprise a damping device. It is possible for the second intermediate member 144 to comprise the aforementioned units in any combination.

[0125] Figure 9C shows a further embodiment of an end effector 146 in which the end effector end section 22 has a third intermediate member 148. The third intermediate member 148 can comprise the three units described above: translational adjustment device, rocker, and damping device, in any combination.

[0126] Furthermore, embodiments of the end effector are also possible in which any combination of the intermediate members 136, 144, 148 shown in Figures 9A to 9C are provided.

[0127] The features disclosed in the above description, the claims and the drawings may be important both individually and in any combination for the realization of the invention in its various forms.

[0128] List of reference symbols

[0129] 2 End effector

[0130] 4 Fastening element

[0131] 6 first end effector section

[0132] 8, 10 pairs of first pivot bearings

[0133] 12 second end effector section

[0134] 14 first rotation axis

[0135] 15 Double arrow

[0136] 16 End effector center section

[0137] 18, 20 pairs of second pivot bearings

[0138] 22 End effector end section

[0139] 24 second rotation axis

[0140] 25 double arrow

[0141] 26 tool holders

[0142] 28 tools

[0143] 30 End effector

[0144] 32 first end effector section

[0145] 34 Fastening element

[0146] 36, 38 Pair of first pivot bearings

[0147] 40 second end effector section

[0148] 42 first rotation axis

[0149] 43 Double arrow

[0150] 44 tool holders

[0151] 46 tools

[0152] 48 End effector

[0153] 50 link of the robot device

[0154] 52 translational adjustment device

[0155] 54 Double arrow

[0156] 56 pole

[0157] 58 spring

[0158] 60 suction nozzles

[0159] 62 Suction hose

[0160] 64 Dust protection sleeve

[0161] 66 Robot device

[0162] 68 Platform

[0163] 70a to 70g links of the robot device

[0164] 72 Robot flange

[0165] 74 joints

[0166] 76 segment ball bearings

[0167] 78 inner segment

[0168] 80 outer segment

[0169] 82 Rotation axis

[0170] 84 balls

[0171] 86 Ball cage Round groove Round groove Square groove Square groove End face of the inner segment End face of the outer segment Round groove Round groove Force flow line -1 , 102-2 Angular contact ball bearing -1 , 104-2 Inner segment -1, 106-2 Outer segment-1 , 108-2 Ball -1 , 110-2 Ball cage First support unit Second support unit Screw connection Clamping element -1 , 117-2 Axial preload force Acting force -1 , 120-2 Force flow line Workpiece surface Double arrow Machining surface Direction of movement Normal force Frictional force End effector First intermediate link First part Second part End effector Second intermediate link End effector Third intermediate link

Claims

PATENT CLAIMS 1. An end effector for attachment to a robot or positioning device (66), the end effector comprising: - a first end effector section (6, 32) having a fastening element (4, 34) designed to be fastened to the robot or positioning device (66), - at least one first pivot bearing (8, 10, 36, 38) mounted on the first end effector section (6, 32), - a second end effector section (12, 40) which is connected to the first end effector section (6, 32) via the at least one first pivot bearing (8, 10, 36, 38) such that the second end effector section (12, 40) is pivotable relative to the first end effector section (6, 32) about a first axis of rotation (14, 42), - wherein the second end effector section (12, 40) comprises a tool holder (26, 44) and a tool (28, 46) held by the tool holder, wherein the tool (28, 46) is designed to machine a surface of a workpiece, - wherein the at least one first pivot bearing (8, 10, 36, 38) is designed such that, when the end effector (2, 30) is placed on a workpiece, the first axis of rotation (14, 42) runs on the workpiece surface (122) or on the side of the workpiece surface (122) facing the workpiece at a distance of less than 10 mm from the workpiece surface (122) or runs on the side of the workpiece surface (122) facing away from the workpiece at a distance of less than 50 mm from the workpiece surface (122), in each case viewed in the normal direction to the workpiece surface.

2. End effector according to claim 1, characterized in that the at least one first pivot bearing is designed such that when the end effector is placed on a workpiece, the distance between the first axis of rotation and the workpiece surface, viewed in the normal direction to the workpiece surface, is less than a quarter of the smallest lateral extent of the effective machining surface of the tool intended for machining the workpiece surface.

3. End effector according to claim 1 or claim 2, characterized in that the at least one first pivot bearing comprises at least one segmented rolling bearing or at least one segmented sliding bearing.

4. End effector according to one of the preceding claims, characterized in that the second end effector section comprises: - an end effector center section, which is connected to the first end effector section via the at least one first pivot bearing such that the end effector center section (and thus the entire second end effector section) can be pivoted relative to the first end effector section about the first axis of rotation, - at least one second pivot bearing mounted on the end effector center section, - an end effector end section which is connected to the end effector center section via the at least one second pivot bearing such that the end effector end section is pivotable relative to the end effector center section about a second rotation axis, wherein the end effector end section comprises the tool holder and the tool, - wherein the at least one second pivot bearing is designed such that, when the end effector is placed on the workpiece, the second axis of rotation runs on the workpiece surface or on the side of the workpiece surface facing the workpiece at a distance of less than 10 mm from the workpiece surface or runs on the side of the workpiece surface facing away from the workpiece at a distance of less than 50 mm from the workpiece surface, in each case viewed in the normal direction to the workpiece surface.

5. End effector according to claim 4, characterized in that the at least one second pivot bearing is designed such that when the end effector is placed on a workpiece, the distance between the second axis of rotation and the workpiece surface, viewed in the normal direction to the workpiece surface, is less than a quarter of the smallest lateral extent of the effective machining surface of the tool intended for machining the workpiece surface.

6. End effector according to claim 4 or claim 5, characterized in that the at least one second pivot bearing comprises at least one segmented rolling bearing or at least one segmented sliding bearing.

7. End effector according to one of the preceding claims, characterized in that the tool is an active tool, in particular one of the following: rotary sander, eccentric sander, orbital sander, belt sander, polishing device.

8. End effector according to one of claims 1 to 6, characterized in that the tool is a passive tool, in particular one of the following: a grindstone, a grinding block covered with sandpaper, a whetstone.

9. End effector according to claim 8, characterized in that the tool is a grindstone or the tool comprises a grindstone.

10. End effector according to one of the preceding claims, characterized in that the end effector is designed so that when the tool holder and the tool are placed on the workpiece surface, the tool holder and the tool align themselves automatically relative to the workpiece surface.

11. End effector according to one of the preceding claims, characterized in that the at least one first pivot bearing comprises a pair of segmented rolling bearings or segmented sliding bearings arranged opposite one another in a mirror image, which form an adjusted bearing.

12. End effector for attachment to a robot or positioning device, the end effector comprising: - a first end effector section having a fastening element adapted to be attached to the robot or positioning device, - at least one first pivot bearing attached to the first end effector section, - a second end effector section which is connected to the first end effector section via the at least one first pivot bearing such that the second end effector section can be pivoted relative to the first end effector section about a first axis of rotation, - wherein the second end effector section comprises a tool holder and a tool held by the tool holder, wherein the tool is designed to machine a surface of a workpiece, - wherein the at least one first pivot bearing comprises at least one segmented rolling bearing or at least one segmented plain bearing.

13. End effector according to claim 12, characterized in that the second end effector section comprises: - an end effector center section, which is connected to the first end effector section via the at least one first pivot bearing such that the end effector center section (and thus the entire second end effector section) can be pivoted relative to the first end effector section about the first axis of rotation, - at least one second pivot bearing mounted on the end effector center section, - an end effector end section which is connected to the end effector center section via the at least one second pivot bearing such that the end effector end section is pivotable relative to the end effector center section about a second rotation axis, wherein the end effector end section comprises the tool holder and the tool, - wherein the at least one second pivot bearing comprises at least one segmented rolling bearing or at least one segmented plain bearing.

14. A processing device comprising: a robot or positioning device, an end effector according to any one of claims 1 to 13, which is attached to the robot or positioning device by means of the fastening element.

15. A method for machining a workpiece surface by means of an end effector attached to a robot or positioning device, the end effector comprising: - a first end effector section having a fastening element with which the end effector is attached to the robot or positioning device, - at least one first pivot bearing attached to the first end effector section, - a second end effector section, which is connected to the first end effector section via the at least one first pivot bearing such that the second end effector section can be pivoted relative to the first end effector section about a first axis of rotation, wherein the second end effector section has a tool holder and a tool held by the tool holder, wherein the tool is designed to machine a surface of a workpiece, the method comprising: - Placing the end effector on a workpiece surface, wherein, when the end effector is placed on the workpiece, the first axis of rotation runs on the workpiece surface or on the side of the workpiece surface facing the workpiece at a distance of less than 10 mm from the workpiece surface or on the side of the workpiece surface facing away from the workpiece at a distance of less than 50 mm from the workpiece surface, in each case viewed in the normal direction to the workpiece surface, wherein the orientation of the tool holder and the tool adapts automatically to the workpiece surface by pivoting the second end effector section about the first axis of rotation.

Images