DE102012008122B4 - Device for multiaxial orientation and / or positioning of a tool - Google Patents

Abstract

Apparatus for multiaxial orientation and / or positioning of a tool (500), comprising a bearing assembly for holding a machining unit (502), the tool (510), and a plurality of movably arranged members for supporting and positioning the tool (510) in space wherein the links comprise a support structure connected via a universal joint (511) to the tool (510) at a first point and two struts (512; 513) acting in two other points of the tool, and the struts (512; 513) respectively along a sliding axis (519; 519a) are movably mounted, characterized in that the bearing arrangement as a portal-like, along two orthogonal successive linear axes (503; 504) movable movement unit (501) is designed, and the support structure as a linear guide system (550) at least biaxial serial displacement kinematics is performed, the minde a displacement of the universal joint (511) at least two mutually perpendicular displacement directions (505; 506), the universal joint (511) having a characteristic point positioned over the linear guide system (550) and only the struts (512; 513) determining the orientation of the tool (510) in space, and the sliding axes (519; 519a) of the struts (512; 513) are arranged so as to enclose an angle of 45 ° to 60 ° with each other and the plane spanned by the sliding shafts (519; 519a) is tilted at an angle of 30 ° to 40 ° to one another of the displacement corrections (506).

Description

The present invention relates to a device for multi-axial orientation and / or positioning of a tool, comprising a bearing assembly for holding a processing unit, which comprises the tool, and a plurality of movably arranged members for storage and positioning of the tool in space, wherein the members via a a universal joint with the tool in a first point connected support structure and two acting in two other points of the tool struts comprise, and the struts are each movably mounted along a sliding axis.

Typical fields of application of such orientation and positioning devices are the welding, cutting, joining or marking of workpieces. As tools, for example, laser, welding or cutting torch to call.

State of the art

For the orientation of rotationally symmetric acting on the material to be processed tools, such as milling heads, oxy-fuel or plasma and laser cutting torches, water jet cutting tools and cameras two rotational axes of motion are sufficient. Pivoting unit, chamfering unit, swivel head or wrist are in the German-speaking countries typical names for such facilities.

The type of arrangement of these axes of motion relative to the tool axis distinguishes two basic principles, which are referred to as polar and gimbal and in the English-speaking world as roll pitch and pitch yaw (Rosheim, ME, Robot Wrist Actuator, John Wiley & Sons New York, Chichester, Brisbane, Toronto, Singapore, 1989). On pivoting units of the pitch-yaw type, the two axes of movement with the burner axis of symmetry form a right angle in the basic or middle position; At such of the principle roll pitch is in this position, a rotation axis with the burner axis of symmetry identical.

Cables and hoses leading to the tool must be guided and guided by the swivel unit in such a way that their function is not impaired and a long service life is ensured. This is especially the case when, as in laser beam cutting with the aid of a solid-state laser, the media transfer from the laser source to the machining head is done by a light guide cable. This is expensive and is immediately destroyed by kinking or drilling stress. In DE 60 2005 006 178 T2 a technical solution is proposed which is based on arranging an optical fiber in a hollow robot arm. The robot arm with the arranged at its end swivel head is assigned to the type roll pitch. It is proposed to compensate for the drastic load acting thereon on the optical fiber by means of a rotary joint which connects a distal and a proximal part of a light guide cable. Frictional and other residual moments continue to affect the fiber optic cable and burden this. Clamping the rotary joint should not be completely ruled out, at least for large swivel angles. Due to the guidance of the optical fiber cable in the hollow robot arm, while the same is well protected against mechanical damage from the outside, there is no longer any visual control possibility.

More suitable technical solutions that lead the fiber optic cable or other hose package exposed and have a cardanic action principle seem better. The protection and gentle treatment of cables and hoses during thermal cutting is the focus of the EP 1 116 543 A2 cited solution. There, a spatial coupling mechanism of the basic structure Pitch-Yaw is described as interlocking arrangement of two planar parallel crank gear. By using this special gear structure, the burner head can be swiveled around its burner tip, the so-called TCP (Tool Center Point). To change the orientation of the burner head no further machine movements are required. It is also proposed to spatially separate the drive and the guide gear with the aim of keeping the moving mass low and increasing the dynamics of the burner movement. The burner is located in front of the mechanism and pivots about its burner tip. Naturally, the collision space of the burner forms a cone and the mechanism must be arranged so that it is outside this cone. The range of motion of the solution, starting from its zero position, is not the same in all directions and is particularly limited when the burner moves in the direction of the mechanism. At the same time, due to its operating principle, the swivel unit must be located very close to the component, which increases the risk of collision. An extremely large number of joints (> 20) is required for the function of the solution described, which at the same time implies that a large number of kinematic dimensions (lengths, angles) must be observed very accurately in order to ensure the required positioning accuracy.

The orientation of a "soul", a torsionally stiff, flexible element in space is dedicated DD 292 170 A5 , This "soul" becomes the core of a spatial coupling gear-like structure that develops and builds around it, ensuring that the "soul" is only curved but not drilled. The structure is no Mechanism in the sense of the definition of such, since the movement of the structure depends on the inner and outer force field. Consequently, it is expected that the stiffness on the one hand, the positioning accuracy of the other hand, this solution are low and the solution is not suitable for precise guidance of a tool.

A similar solution, without the torsionally stiff, elastic "soul" contains DD 295 118 A5 , Here is a true mechanism described, consisting of a very large number of limbs and joints. Several universal joints are arranged in succession, the mechanism serves to translate the total swing on partial pivoting at the successively arranged universal joints. A fundamental limitation of the swivel angle does not exist, by adding more "sub-gearbox" could theoretically increase the achievable swivel angle, but this also further increases the number of links and joints. Links and joints are always subject to play and tolerance. The structure principle described owns a high transmission ratio, ie small movements on the drive lead to relatively large movements on the output. Play and tolerance translate nonlinearly into positioning errors and lead to the result that even with this solution no high-precision positioning of a tool can be realized.

A simpler structure consisting only of a universal joint is in DE 20 2008 013 727 described. Two "... projecting protruding sections ..." are determined by two drives in their position, are preferably perpendicular to each other and determine in their interaction the direction of an output member. The drives, referred to as "power sources", act on the mechanism with "transmission rods" and can be arranged largely freely relative to the structure. The output member forms with the "... curved projecting portions (s) ..." each have a spherical loop joint with the joint degree of freedom f = 2 and has a line contact with these. As a result, it is to be expected that, on the one hand, large forces can not be transmitted and, on the other hand, an approximately backlash-free mobility, if at all, can only be realized with very high production outlay. The structure builds around the universal joint, it seems hardly possible to integrate a burner head in the structure, but the burner head should be located outside the structure. Thus, the axis of symmetry of the burner head can cross the axes of the universal joint at only a small distance, which is very unfavorable for kinematic and collision reasons.

It also seems obvious to realize the movement of the burner head with a parallel structure, commonly known as platform. Three-axis solutions, driven by slides, rockers or loops, are well known (Müglitz, J .; Schönherr, J., Weidermann: Design and construction of a parallel manipulator with the degree of freedom F = 3. Camshaft, linkage, controlled drive solutions in motion technology. VDI Transmission Conference 1996, Veitshöchheim, 17./18.9.1996, VDI Reports No. 1281, VDI-Verlag Dusseldorf, 1996). Their pivot angle is limited, but can be increased by several platform elements are arranged one behind the other, as in DE 196 38 765 A1 is described. The result is a proboscisike movement behavior, which leads to large compensating movements at the proximal end of the mechanism in the case of pivotal movements fixed at one point.

These are undesirable because they lower the possible orientation speed, reduce the unrestricted orientation workspace, and generally reduce positioning accuracy.

Platforms with six (hexapod) or five (pentapod) legs and thus a degree of freedom of F = 6 or F = 5 allow pivoting movements around a fixed point in space.

Hexapods of the STEWART type (Stewart, D .: A platform with six degrees of freedom, Proc. Of the Inst. Of Mech. Eng. 180 (1965) 1, pp. 371-386) or GOUGH (Gough, VE: Contribution to In a study of automotive stability and control in tire performance, by Cornell Staff, Proc. Auto., Inst. Mech. Eng (1956), pp. 392-395) are - in all directions - in their achievable swivel angle limited to about +/- 30 degrees. A typical example of a hexapod-based machine is FANUC robot F200iB (Prospectus Materials, ^© 2005 FANUC Robotics America, Inc. FANUC ROBOTICS LITHO IN USA FRA-6/05).

Easier to handle and equipped with the ability to achieve a greater swing angle are pentapods, ie machines with parallel structure, which have five legs or struts between frame and platform, four of which are identical and each have a ball and a universal joint and a leg is connected on both sides with a universal joint with the frame and with the platform. The use of a pentapod to build a five-axis milling machine describes EP 1 439 934 B1 , Five struts move and orient a slide in space. The struts are preferably designed as spindles, ie, the length of the individual platform legs is variable. However, an embodiment with movable articulation points is set forth. The Joints of the struts are described both as such with intersecting axes and as intersecting axes. The dimensioning is made so that in a preferred direction, a very large tilt angle is reached, at the expense of other directions. A closed, frame-shaped frame based on an icosahedron would give the solution a very high rigidity, which is also required to qualify the solution for the purpose of milling. The limited swing angle in all other than the preferred direction is compensated by a turntable on which the part to be machined is clamped.

EP 1 863 734 B1 describes a tripod, ie the guidance of a point in space with three drives. The output member is fixed in a universal joint by a parallel guide and is moved by three drive arms, which are designed as rockers in space. All drives are fixed to the frame, which is why only small masses have to be moved and a very high dynamic range can be achieved. The tool head is fixed in its relative position to the frame by various solutions, which ultimately can all be attributed to a parallel crank.

In US 2007/0248428 described is a mechanism with the degree of freedom F = 3. Three parallel thrust axes are connected to the frame by being preferably arranged symmetrically on the inside of a cylindrical housing. Connected to the three thrust axes via slides is a first, largely rotationally symmetrical, annular holding member, which consequently can only be moved in the direction of the thrust axes. With two first, on the holding member opposite pins arranged pivotally connected to this is a second, again annular member, which connects with two further pins, whose axial direction is perpendicular to the first pin, a connection to the spindle head, the working member. The axes of the pins intersect at right angles. The holding members, in cooperation with the slides, form a movable structure supporting the spindle head. The succession arrangement of the holding members describes, in cooperation with the pins, a universal joint movable along the push axes. Are hinged to the spindle head three, only normally loaded members that are connected in any way with the frame. The document describes coupling rods that are moved with three sliders on the push axes, also gimbal connected to the frame thrust cylinders or cranks. The advantage of this solution is a stiff, compact design, well suited for comparatively small tools and small tilt angles with high reaction forces arising from the technological process. The disadvantage of the solution consists in limited by the cylindrical housing with the thrust axes arranged in it collision space, so long projecting tools, such as plasma or laser cutting heads, which must be simultaneously pivoted by a high, amounting to 45 degrees swing angle, collide with the coupling rods would.

A generic prior art is known from EP 2 174 742 B1 known, which describes a "cutting device ...". It is a mechanism with the degree of freedom 2 ie two drives move one output member around or along two axes. A tool is encompassed by a "... annular insert ..." and rotatable relative thereto about a first axis, whereas the annular insert about a second, crossed or skewed to the first axis about a second axis in a ".. "Recording ..." is movable. From a kinematic point of view, this arrangement is a simple universal joint. By two linear drives, which are firmly connected to the "... receptacle ...", the tool is pivoted about the axes of the universal joint. However, such a structure has long been known and used for many purposes in industrial practice. So z. For example, it is described how two working cylinders pivot a link mounted around a frame (Volmer, J .: Industrial Robots - Function and Design, Verlag Technik GmbH Berlin, Munich, 1992, pp. 113, 114). DE 199 82 943 describes a similar arrangement of special construction vehicles, so-called Motorgradern, by means of a dozer blade rotated relative to a vehicle frame by a "... shield sub-assembly ..." and the "... shield sub-assembly ..." about two axes, a cross and a pitch, to the vehicle frame by means of two hinged to the vehicle frame hydraulic cylinder can be oriented.

In EP 2 174 742 would have, unlike the description given, to the function of the mechanism of each of the two pairs of hinges that attack on the "... bars ...", designed as a ball joint.

From the DE 199 52 423 A1 is a processing machine for multi-axis moving a tool known, with the position and orientation of the tool via three parallel kinematic linear actuators are adjustable. The linear actuators are each connected via a ball or universal joint with a holder for the tool.

The publication DE 102 16 571 A1 discloses a device for moving a working head in space. The device comprises a platform which is two-dimensionally movable in a plane and which carries a rotary element on which the working head is movably supported by means of displaceable rods.

Technical task

The invention has for its object to provide a device that is simple and inexpensive to manufacture and at the same time allows precise movement, positioning and / or orientation of a tool in space in high quality of motion, high dynamics and the greatest possible collision distance to the workpiece and is capable of performing small Cartesian movements.

Brief description of the invention

This object is achieved on the basis of a device of the type mentioned in the present invention, that the bearing assembly is designed as a portal-like, along two orthogonal successive linear axes movable movement unit, and the support structure is designed as a linear guide system with at least biaxial serial displacement kinematics, which is a displacement of the universal joint in at least two mutually perpendicular displacements allowed, wherein the universal joint has a characteristic point which is positioned over the linear guide system and only the struts determine the orientation of the tool in space, and the sliding axes of the struts are arranged so that they are at an angle of 45 ° to 60 °, and the plane spanned by the sliding axes plane tilted by an angle of 30 ° to 40 ° to one of the displacement directions of the linear guide system.

The device according to the invention comprises a processing unit and a bearing arrangement. It is preferably suitable for multiaxial orientation and / or positioning of a rotationally symmetrical tool. The bearing assembly is designed like a portal and is used to connect the processing unit. This includes the machining tool and a plurality of movably arranged members for storage and positioning of the tool in space. A bearing arrangement in the form of a portal-like movement unit allows a quick and easy positioning of the processing unit and thus also of the tool in the room. The portal-like movement unit is movable in two spatial directions along two orthogonal linear axes. The movement is done with serial kinematics. The portal-like movement unit is particularly suitable for virtually unlimited translational movements of the processing unit.

The members of the processing unit engage the tool directly or indirectly via intermediate elements, such as on a tool carrier, on or in which the tool is held. A tool carrier facilitates assembly and allows easy replacement of the tool. In this case, the tool is attached to the tool carrier during the intended use of the device such that the movement of the tool carrier is transferred to the tool and thus a movement of the tool carrier thus consecutively causes a movement of the tool. Unless expressly stated otherwise, both the direct and indirect action of the links on the tool shall be included in the following explanations, even if a tool carrier is not expressly mentioned.

For storage and in particular for positioning of the tool in space, the invention provides that the support structure connected via a universal joint to the tool at a first point is designed as a linear guide system with at least biaxial serial displacement kinematics. Such a linear guide system allows a movement of the universal joint and thus of the tool in at least two spatial directions.

Each universal joint has a so-called "characteristic point", which defines its position in space and which is determined for example by the intersection of the two axes of rotation of the universal joint. The displacement kinematics connected to the tool via the universal joint enable positioning of the characteristic point of the universal joint and thus positioning of the tool in at least one spatial plane. The movable struts acting on at least two other points of the tool determine the position of the tool body in space and are thus provided for adjusting the orientation of the tool in space. Only the struts determine the orientation of the tool in space.

Characterized in that the connection of the tool with the linear guide system via a universal joint, the tool is initially arranged to be movable about the two axes of the universal joint. This mobility is prevented on the one hand by the struts acting in two other points of the tool, on the other hand it determines the orientation of the tool in space. The struts are parallel kinematic connected to the processing unit. As a result, only a comparatively small mass has to be moved by the struts, so that the orientation can be adjusted with high dynamics and accuracy.

According to the invention, it is further provided that the sliding axes of the struts are arranged such that they enclose an angle of 45 ° to 60 ° with each other. Such an arrangement the sliding axes allows a high-quality motion transmission in the entire range of deflection and movement of the tool.

Also, the fact that the plane spanned by the sliding axes plane tilted by an angle of 30 ° to 40 ° to one of the displacement directions of the linear guide system, the motion quality is improved. At an inclination angle of the plane with respect to the displacement direction of the linear guide system of less than 30 °, the effect loses on the improvement of the motion quality. With an angle of inclination of more than 40 °, small movements along the sliding axes only lead to a comparatively slight change in position of the tool, as a result of which rapid positioning of the tool is impaired. Due to the structure of the links, in particular the linear guide system, the center of gravity of the entire device changes only slightly during the positioning and orientation of the tool. As a result, the elastic deformation of the device remains approximately constant and it is a precise guidance of the tool supported even with pivoted tool. This results in a simple design and high dynamics of the processing device precise movement, positioning and / or orientation of the tool.

In a first advantageous embodiment of the device according to the invention it is provided that the linear guide system for displacement in one of the displacement directions a lifting axis, and that the universal joint has a proximal and a distal pivot axis, wherein a rotatable about the distal hinge axis and acting on the tool U-shaped yoke is provided, on which the tool is rotatably mounted about the proximal hinge axis of rotation, and wherein a connecting web of the yoke between a tool axis of symmetry and the lifting axis is arranged.

The tool includes a tool head and a tool shank. The "tool symmetry axis" is the longitudinal axis running through a tool tip of the tool head and the tool shank.

The lifting axis refers to an axis along which the processing unit can be raised or lowered by means of the linear guide system and which enables a height adjustment for the tool. It corresponds to a displacement direction of the linear guide system.

A yoke comprises at least two interconnected via a connecting web, free leg. The universal joint has a proximal and a distal joint axis of rotation. According to the invention a U-shaped yoke is provided on the linear guide system, which is rotatably mounted about the distal pivot axis. The yoke further has a proximal pivot axis of rotation on which the tool is rotatably mounted.

According to the invention it is provided that the connecting web of the yoke between the tool axis of symmetry and the lifting axis is arranged. Such an arrangement of the connecting web, in addition to a simple assembly of the tool, a quick tool change and short set-up times possible.

In a further likewise preferred modification of the device according to the invention, it is provided that the distal joint rotational axis runs between the tool axis of symmetry and the lifting axis, wherein the distal joint axis does not intersect the tool axis of symmetry.

According to the invention, the distal joint rotational axis of the universal joint extends between the tool axis of symmetry and the lifting axis. The fact that the distal joint axis does not intersect the tool axis of symmetry increases the quality of movement.

It has proven useful if the struts are attached to the linear guide system.

The fact that the struts are attached to the linear guide system, they are moved in a movement of the linear guide system. They are therefore dimensioned correspondingly smaller and have a lower mass, so that a more compact design of the device according to the invention is made possible. Since adjustment of the orientation means that less masses have to be moved, a higher guidance accuracy and a higher dynamics of the device are also ensured.

It has proven to be advantageous if the tool has a tool head, and the tool head against a vertical position by at least 40 °, preferably at least 45 °, more preferably at least 50 °, in all directions is pivotally, with the proviso that the Struts are connected in each case via a ball joint with the tool and in each case with a slide driving them, wherein the range of motion of the ball joints with respect to the zero position is at most ± 30 °.

A ball joint comprises two joint elements, a ball head and a ball socket; it allows for a rotational movement about all three axes but translationally fixed. A strut, which is connected to a ball joint, is thus translatorily bound and suitable for determining the orientation of the tool. At the same time, however, the ball joint also allows a rotational movement of the strut about the three axes of rotation of the ball joint, wherein a coupling rod along its longitudinal axis has an isolated freedom. For ball joints, the working angle (deflection angle) is limited by the ball socket. The inventive arrangement of the links allows pivoting of the tool head by at least 40 °, preferably by at least 45 °, more preferably by at least 50 °, wherein the ball joint are deflected at most ± 30 ° relative to the zero position.

It has proven useful if the tool has a tool center point whose position in the space is variable, with the proviso that when changing the orientation of the tool in space the tool center point is spatially fixed with the help of the linear guide system.

The tool center point of the tool is a calculated, freely selectable reference point, for example, the machining point on the workpiece, such as the focus on a laser tool. The position of the tool center point is variable in space, so that it is moved, for example, during the positioning of the tool, that is, for example, during a displacement by means of the linear guide system or the portal-like movement unit. According to the invention, the tool center point is characterized in that it remains fixed in space with a change in the orientation of the tool in cooperation with the linear guide system. This allows easier control of the tool as the position and orientation of the tool can be considered separately in the control. In addition, a separate consideration of the position and orientation of the tool is also kinematically advantageous, since only relatively small masses have to be moved during orientation changes. As a result, quick orientation changes of the tool are possible. Preferably, the tool center point is spaced from the characteristic point of the universal joint.

In an alternative embodiment of the device according to the invention it is provided that the bearing mounted on the bearing assembly linear guide system has a biaxial-serial displacement kinematics, which allows a displacement of the universal joint in a first displacement direction and in a direction perpendicular to the first direction of displacement, second displacement direction, wherein the first displacement direction of the linear guide system is perpendicular to the two linear axes of the movement unit and the second displacement direction of the linear guide system is redundant to a linear axis of the movement unit.

The displacement directions of the biaxial-serial displacement kinematics are perpendicular to each other; they span a plane of movement. In order to enable a movement of the tool in all three spatial directions when using a two-axis linear guide system, the linear guide system is connected to the portal-like movement unit such that the first displacement direction of the linear guide system is perpendicular to the two linear axes of the movement unit. This can be avoided in the linear guide system, the third displacement axis and the associated design and control effort.

Advantageously, moreover, it is provided that the second displacement direction of the linear guide system is redundant to a frame-proximal linear axis of the movement unit. Due to the redundancy of these two axes, movements along the redundant axis can take place both via the portal-like movement unit and via the linear guidance system. With only small movements in the direction of the redundant axis, it is advisable to carry out this movement by means of the linear guide system. For in a movement of the linear guide system must be compared to a movement of the portal-like movement unit lower masses move. A movement in the direction of the redundant axis by the linear guide system therefore leads compared to a movement on the portal-like movement unit to a higher dynamics of the device and has the consequence that with small movements high accuracy of the tool can be achieved.

It has proved to be advantageous if, for a movement along one of the axes of the displacement kinematics of the linear guide system, a cylindrical telescope unit with an inner cylinder and outer cylinder is provided.

In a cylindrical telescopic unit with a non-circular cylinder cross-section rotation of the inner cylinder is prevented about its longitudinal axis.

A cylindrical telescopic unit with a non-circular cylinder cross-section allows the setting of the smallest possible distance between the tool and the bearing assembly. The telescopic unit also leads to an increase in the range of movement of the tool.

Preferably, the universal joint is at the tool facing the distal end of the Inner cylinder attached. Both the outer cylinder and the inner cylinder of the telescope unit have a distal end facing away from the tool and a proximal end facing away from the tool. By a mounted at the distal end of the inner cylinder universal joint a compact design of the linear guide system is made possible. The inner cylinder has compared to the outer cylinder usually due to its smaller footprint on a lower weight. The fact that the universal joint is mounted on the inner cylinder, a relatively small mass must be moved during extension of the telescopic unit, so that a device with a higher dynamics is obtained.

In a preferred embodiment of the device according to the invention it is provided that for setting the relative position of the inner cylinder and outer cylinder a translatory or a rotary drive is provided, which is connected to the inner cylinder and / or the outer cylinder via a clamp, and that a sensor is provided, which detects the movement of the Gehemmes.

In order to avoid machine damage during collisions of the tool with its surroundings, for example, a workpiece to be machined, the inner cylinder and / or the outer cylinder is connected to the drive via a clamp, on which a sensor for detecting a movement of the Gehemmes is provided. The measured variable determined by means of a sensor can be used, for example, as a basis for a collision calculation.

It has proven useful when the telescopic unit is designed in the manner of a drawer by a remote from the tool, proximal, a closed frame forming frame enclosing a distal, the tool facing, box-shaped slide.

A telescopic unit in the form of a drawer with a frame and a box-shaped slide is easy to manufacture and allows through the flat outer surfaces easy mounting of the telescope unit.

It has proved to be advantageous if the proximal, frame-shaped frame and the distal box-shaped slider are determined in their relative position by a translational or rotary drive, the frame-near and the frame remote part of the drive not direct, but a guided over a connection either connection have to the proximal, frame-shaped frame or the distal, box-shaped slide and relative movements of Gehemmes be detected by a sensor.

The clamp serves to avoid collisions of the tool with the environment and is in operative connection with a sensor. The sensor is suitable for determining a path measurement.

A further advantageous embodiment of the device according to the invention is characterized in that the processing unit has a center of gravity, which is approximately fixed in space with a change in the orientation of the tool in space.

Due to the fact that, when the orientation of the tool changes, the center of gravity of the mass is approximately fixed in space, the center of gravity of the device changes only slightly. Due to the approximately constant center of gravity a precise guidance of the tool is also possible with swiveled tool.

In an advantageous embodiment of the device according to the invention, it is provided that the tool comprises a laser head with a laser head symmetry axis, a beam feed with a beam feed axis and a beam deflection unit for feeding the laser beam to the laser head, the laser head symmetry axis and the beam feed axis being offset from one another in such a way that the beam feed axis Seen in the distal direction of the linear guide system is arranged behind the laser head axis of symmetry.

The linear guide system has a distal direction, which extends from the bearing assembly along one of the displacement axes of the linear guide system in the direction of the tool. The opposite direction to the distal direction is called the proximal direction. The beam feed axis and the laser head symmetry axis are offset and preferably in parallel planes. The staggered arrangement leads to a lower height of the laser head in the direction of the laser head axis of symmetry. Due to the smaller space required by the laser head, the laser head can be tilted at a greater angle during the tilting in the proximal direction without the laser head colliding with the linear guide system or the bearing arrangement, so that a large working range is obtained.

It has proved to be advantageous if the tool comprises a tool head facing front and a rear end, wherein the universal joint is connected to the front end of the tool. The arrangement of the universal joint at the front end of the tool results in a small distance between the tool tip and the axes of movement of the Universal joint, which allows high accuracy of the tool and precise machining of the workpiece. The front end of the tool is understood to be the longitudinal section between the frontal end and the middle between the two ends.

In a zero position, the tool preferably has a longitudinal side facing the bearing arrangement and a longitudinal side facing away from the bearing arrangement, wherein all the links are connected to the longitudinal side of the tool facing the bearing arrangement.

The zero position is the initial setting that the processing unit usually occupies when switching off the device and allows a generally equal displacement of the tool in both directions.

The links are on the one hand with the bearing assembly and on the other hand with the tool in operative connection. Since the tool is a three-dimensional body, it has, in the zero position, a longitudinal side facing the bearing arrangement and facing away from the bearing arrangement. All members of the processing unit engage on a common longitudinal side of the tool, namely on the bearing assembly of the facing longitudinal side of the tool. The opposite longitudinal side is thus free of links, which reduces the risk of collisions between the processing device with a workpiece to be machined. In addition, the bearing assembly does not surround the tool and can be made simple and compact.

The movable support of the struts along a sliding axis contributes to adjustment of the orientation of the tool. The direction and length of the sliding axis determines the mobility of the struts. To move the struts a provided with a drive slide is provided, which is fixed to the linear displacement unit. In contrast to a fixation of the drive to the bearing assembly whose attachment to the linear guide system has the advantage that the drive of the struts is moved with the linear guide system, whereby a more compact design of the processing unit is made possible. In a particularly preferred modification of the device is provided that the logical arrangement of the links and joints with each other in model representation results in several self-contained mesh and the tool head is part of exactly two mesh.

The transmission of the inventive arrangement of the limbs and joints in a two-dimensional representation shows a network of edges (limbs) and nodes (joints). The edges and nodes form the meshes of the network. A mesh is the shortest possible closed train of edges and knots; it starts from a node and leads back to the same node. It is inventively provided that the tool head is part of exactly two stitches.

Preferably, the tool has two spaced apart hinge elements which are permanently connected to the tool and which are each part of different meshes.

A joint has several joint elements. Joint elements are in the case of a ball joint, for example, the ball socket or the ball head or in the case of a universal joint, for example, a bracket of the universal joint. At least two hinge elements are permanently connected at different points with the tool, so that they are part of different meshes.

The tool is for example a laser or a burner for the thermal processing of workpieces, such as cutting or welding torches, in particular autogenous or plasma torches. The tool has a tool head and a tool shank. In the shaft, a connection element for a universal joint is integrated. The connection element is designed, for example, in the form of a connecting piece, a flange or a joint element which is part of the universal joint. The joint element is for example a joint fork of the universal joint. Characterized in that a connecting element of the universal joint is integrated into the tool shaft, a predetermined, defined geometric association between the tool and the above-described processing unit is ensured, which is reproducible even when changing and replacing the tool without further action. This also makes the tool change faster.

Preferably, at least one joint element, which is provided for connecting the tool to a strut, is integrated in the tool shank.

The connection of the movable struts to the tool, for example via a ball joint or a universal joint. The joints have several joint elements. In the case of a ball joint, a joint element is, for example, the ball socket or the ball head. The joint elements integrated in the tool shank contribute to the reproducibility of the mutual arrangement of tool and machining unit as well as the possibility of a quick and reproducible tool change. In addition, the additionally provided on the tool shaft joint elements increase the stability of the connection of the Tool. Preferably, exactly two further joint elements are integrated in the tool shank, which are provided for connecting the tool to a strut.

embodiment

The invention will be described in more detail with reference to embodiments and a drawing. It shows in a schematic representation:

1 an abstracted, two-dimensional representation of the links and joints of the device according to the invention for orientation and / or positioning of a tool,

2 an embodiment of the device according to the invention, in which the bearing arrangement for holding a processing unit is designed as a portal-like, serially movable movement unit,

3 a processing unit according to 1 in an enlarged view, and

4 an embodiment of a burner for use as a tool in the device.

1 shows in diagram A a two-dimensional, abstracted representation of an arrangement of the links and joints of a device according to the invention indicated, the total reference numeral 300 assigned. The device has a bearing arrangement 310 on. It comprises two struts acting on the tool 301 . 302 , each on the one hand via a ball joint 303 . 304 with the tool and on the other hand via a universal joint 305 . 306 with the bearing arrangement 310 are connected. At the bearing arrangement 310 is also a linear guide system 307 arranged with a three-axis-serial displacement kinematics, via a universal joint 308 connected to the tool.

Diagram B shows a two-dimensional, abstracted representation of an alternative device according to the invention, the overall reference number 400 assigned. The device includes a bearing assembly 401 connected linear guide system 402 with three-axis serial displacement kinematics, via a universal joint 403 connected to the tool. On the linear guide system grab two struts 404 . 405 on the one hand via a ball joint 406 . 407 with the linear guide system and on the other hand also via a ball joint 408 . 409 connected to the tool. The distal direction is in the direction of the arrow 410 ,

2 shows a first embodiment of the device according to the invention, the total reference numeral 500 assigned. The device 500 includes a portal-like serial motion unit 501 and a processing unit 502 with a laser cutting torch 510 attached to the movement unit 501 is held.

The movement unit 501 is along the two orthogonal linear axes 503 . 504 movable. The laser cutting torch 510 is through the linear guide system with a sliding kinematics along the displacement axes 505 . 506 (represented by arrows) movable in two spatial directions. Along the displacement axis 505 the processing unit can be raised or lowered. It serves to adjust the height of the tool and is also referred to as the lifting axis. The displacement axis 506 runs parallel to the linear axis 503 the movement unit 501 and is therefore redundant to this. Both displacement axes 505 . 506 run perpendicular to the linear axis 504 , Small movements of the laser cutting torch 510 in the direction of the redundant axes 503 . 506 done by the linear guide system via a displacement along the displacement axis 506 , large movements of the laser cutting torch 510 be from the portal-like, serial motion unit 501 accepted.

In 3 is the linear guide system 550 the processing unit 502 shown enlarged. The linear guide system 550 has a biaxial-serial displacement kinematics, which is a displacement along the displacement axes 505 and 506 allows. For a movement along the displacement axis 506 is a telescope unit 522 provided, which is designed in the manner of a drawer. The drawer includes a laser cutting torch 510 remote frame 523 and a laser cutting torch 510 facing box-shaped slide 524 , For adjusting the relative position of the frame 523 and box-shaped slider 524 is a translatory drive 580 intended. The box-shaped slide 524 is via a clamp with a sensor (not shown) with the translatory drive 580 connected. At its distal end is the box-shaped slider 524 fork-shaped. The joint fork 596 forms with the box-shaped slide 524 around the distal pivot axis 597 a swivel joint 596 includes two free legs 596b . 596c , which have a connecting bridge 596a connected to each other. At the connecting bridge 596a is the tool around a proximal hinge axis 594 rotatably mounted. The connecting bridge 596a is arranged to be between the displacement axis 505 (Stroke axis) and the tool axis of symmetry 590 of the laser cutting head 514 runs. Also the distal joint axis 597 runs between the lifting axis and the tool axis of symmetry 590 , Tool axis of symmetry 590 and distal pivot axis 597 thus do not cut.

The laser cutting torch 510 includes a laser head 514 with a tool axis of symmetry 590 , a beam deflecting unit 571 and a beam feed 570 with a beam delivery axis 570a , The universal joint is with the front end of the laser head 514 connected. In addition, with the laser head 514 two length-invariable struts 512 . 513 connected. For movable connection of the struts 512 . 513 to the laser head 514 are ball joints 516 intended. The aspiration 512 . 513 are along the sliding axes 519 . 519a movably mounted. To move the struts 512 . 513 along the sliding axes 519 . 519a are sliders 520 provided, on the one hand, with the struts 512 . 513 over a ball joint 521 and on the other hand with a drive 580 are connected. The sliding axes 519 . 519a are arranged so as to enclose an angle of 53 °. They span a plane that tilts at an angle of 36 ° to the direction of movement 506 runs. Due to the tilted arrangement of the plane is between the laser head 514 and the sliding axes 519 . 519a a bulge 560 receive.

At a tilt of the laser cutting head 514 in the direction of the bearing assembly 501 a collision with the linear guide system and in particular with the sliding axes 519 . 519a to avoid, points the laser cutting torch 510 a beam deflecting unit 571 on, the laser beam to the laser head 514 leads. Through the beam deflection unit 571 the beam feed axis run 571 and the tool axis of symmetry 590 (Laser head symmetry axis) offset from each other. This staggered arrangement leads to a smaller extension of the laser head 514 in the direction of the laser head symmetry axis. Due to the smaller space requirement of the laser head 514 the laser head can tilt against the distal direction 565 in the bulge 560 and thus be tilted at a greater angle without the laser head 514 with the sliding axes 519 . 519a collided. As a result, a large work area of the laser head 514 receive.

In zero position points the laser cutting torch 510 one of the bearing assembly facing side 517 and a side facing away from the bearing assembly 518 on. Both the aspiration 512 . 513 as well as the linear guide system are with the bearing assembly facing side 517 of the laser cutting torch 510 connected. By the arrangement of the struts 512 . 513 and the universal joint 511 is the tool head relative to the vertical position by 50 ° in all directions pivotally, the ball joints 516 . 521 be deflected by a maximum of 30 °. The orientation of the laser cutting torch 510 is through the struts 512 . 513 established. When changing the orientation of the laser cutting torch 510 is the center of mass of the processing unit approximately space fixed.

The tool center point is the focus of the laser, which usually lies on the surface of the workpiece to be machined. When changing the orientation of the laser cutting torch 510 With the help of the linear guidance system, the Tool Center Point can be held in a fixed space.

In 4 is an embodiment of a tool in the form of a laser cutting torch 100 shown for use in the device according to the invention. The laser cutting torch 100 has a shaft 101 and a laser cutting head 102 on. In the shaft 101 is a connection element for a universal joint in the form of a nozzle 105 integrated, which can be connected via a flange with the universal joint (not shown in the figure). The stub 105 is stuck to the shaft 101 connected. A connection of the neck 105 with the processing unit takes place along the second axis of rotation 107 of the universal joint. In addition, in the shaft 101 two joint elements 108 . 109 integrated for connecting the laser cutting torch 100 are provided on the above-mentioned movable struts of a processing unit according to the invention. The joint elements 108 . 109 are ball heads of a ball joint. They are above the joint element holders 103 . 104 with the shaft 101 connected.

Claims (14)

Device for multiaxial orientation and / or positioning of a tool ( 500 ), comprising a bearing arrangement for holding a processing unit ( 502 ), which is the tool ( 510 ), and a plurality of movably arranged members for the storage and positioning of the tool ( 510 ) in the space, the links being connected via a universal joint ( 511 ) with the tool ( 510 ) supporting structure connected in a first point and two struts acting in two other points of the tool ( 512 ; 513 ), and the aspirations ( 512 ; 513 ) each along a sliding axis ( 519 ; 519a ) are movably mounted, characterized in that the bearing arrangement as a portal-like, serially along two orthogonal successive linear axes ( 503 ; 504 ) movable movement unit ( 501 ), and the support structure as a linear guide system ( 550 ) with at least two-axis serial displacement kinematics, which is a displacement of the universal joint ( 511 ) in at least two mutually perpendicular displacement directions ( 505 ; 506 ), the universal joint ( 511 ) has a characteristic point which, via the linear guide system ( 550 ) and only the struts ( 512 ; 513 ) the orientation of the tool ( 510 ) in the room, and the sliding axes ( 519 ; 519a ) of aspiration ( 512 ; 513 ) are arranged so that they enclose an angle of 45 ° to 60 ° with each other, and by the sliding axes ( 519 ; 519a ) plane spanned by an angle of 30 ° to 40 ° tilted to one of the displacement directions ( 506 ) runs. Apparatus according to claim 1, characterized in that the linear guide system ( 550 ) for shifting in one of the displacement directions ( 505 ; 506 ) a Hubachse, and that the universal joint ( 511 ) a proximal ( 594 ) and a distal pivot axis ( 597 ), one around the distal pivot axis ( 597 ) rotatable and on the tool ( 510 ) attacking U-shaped yoke ( 596 ) is provided, on which the tool ( 510 ) about the proximal pivot axis ( 594 ) are rotatably mounted, and wherein a connecting web ( 596a ) the yoke ( 596 ) between a tool axis of symmetry ( 590 ) and the lifting axis is arranged. Device according to claim 2, characterized in that the distal pivot axis ( 597 ) between the tool axis of symmetry ( 590 ) and the stroke axis, wherein the distal universal joint axis ( 597 ) the tool symmetry axis ( 590 ) does not cut. Device according to one of the preceding claims, characterized in that the struts ( 512 ; 513 ) on the linear guide system ( 550 ) are attached. Device according to one of the preceding claims, characterized in that the tool ( 510 ) has a tool head and the tool head with respect to a vertical position by at least 40 °, preferably by at least 45 °, more preferably by at least 50 °, is pivotable in all directions, with the proviso that the struts ( 512 ; 513 ) each via a ball joint ( 516 ; 521 ) with the tool ( 510 ) and each with a driving them slide ( 520 ), wherein the range of motion of the ball joints ( 516 ; 521 ) is at most ± 30 ° with respect to the zero position. Device according to one of the preceding claims, characterized in that the tool ( 510 ) has a tool center point whose position in space is variable, with the proviso that when changing the orientation of the tool ( 510 ) in the space of the tool center point with the assistance of the linear guidance system ( 550 ) is fixed in space. Device according to one of the preceding claims, characterized in that the mounted on the bearing assembly linear guide system ( 550 ) has a biaxial-serial displacement kinematics, which is a displacement of the universal joint ( 511 ) in a first direction of displacement ( 505 ) and in a direction perpendicular to the first direction of displacement ( 505 ), second shift direction ( 506 ), the first direction of displacement ( 505 ) of the linear guide system ( 550 ) perpendicular to the two linear axes ( 503 ; 504 ) of the moving unit ( 501 ) and the second shift direction ( 506 ) of the linear guide system ( 550 ) redundant to a linear axis ( 503 ) of the moving unit ( 501 ). Device according to one of the preceding claims, characterized in that for movement along one of the axes ( 505 ; 506 ) of the sliding kinematics of the linear guide system ( 550 ) a cylindrical telescope unit ( 522 ) with an inner cylinder ( 524 ) and outer cylinder ( 523 ) is provided. Device according to claim 8, characterized in that the universal joint ( 511 ) on which the tool ( 510 ) facing, distal end of the inner cylinder ( 524 ) is attached. Device according to one of claims 8 or 9, characterized in that for adjusting the relative position of inner cylinder ( 524 ) and outer cylinder ( 523 ) a translatory or a rotary drive is provided, which with the inner cylinder ( 524 ) and / or the outer cylinder ( 523 ) is connected via a clamp, and that a sensor is provided which detects the movement of the Gehemmes. Device according to one of the preceding claims 8 to 10, characterized in that the telescopic unit ( 522 ) is designed in the manner of a drawer by a tool ( 510 ) facing away, proximal, a closed frame forming frame enclosing a distal, the tool facing, box-shaped slide. Apparatus according to claim 11, characterized in that the proximal, frame-shaped frame and the distal box-shaped slide are determined in their relative position by a translational or rotary drive, wherein the frame near and the frame remote part of the drive not direct, but a guided over a terminal connection have either the proximal, frame-shaped frame or the distal, box-shaped slide and relative movements of the Gehemmes be detected by a sensor. Device according to one of the preceding claims, characterized in that the processing unit ( 502 ) has a center of gravity which, upon a change in the orientation of the tool ( 510 ) is approximately spatially fixed in space. Device according to one of the preceding claims, characterized in that the tool ( 510 ) a laser head ( 514 ) with a laser head symmetry axis, a beam feed ( 570 ) with a beam feed axis ( 570a ) and a beam deflecting unit ( 571 ) for the supply of the laser beam to the laser head ( 514 ), wherein the laser head symmetry axis and the beam feed axis ( 570 ) offset from one another in such a way that the beam feed axis ( 570 ) in the distal direction of the linear guide system ( 550 ) is arranged behind the laser head axis of symmetry.

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