Joint arrangement

Abstract

Joint arrangement comprising a first joint body (2) and a second joint body (3) which is pivotable about a pivot center (7) with respect to the first joint body (2) by performing a working swivel movement (6) and which can be positioned in different working swivel positions, wherein the first joint body (2) has a ball socket (9) in which the second joint body (3) is rotatably mounted with a ball head (8) about the pivot center (7) to enable the working swivel movement (6), and wherein the second joint body (3) has an imaginary principal axis (12) which intersects the pivot center (7), - wherein two rotatable drive units (4, 5) are arranged on the first joint body (2), wherein a first drive unit (4) of the two drive units (4, 5) can be driven to a first drive rotary movement (47) about a first axis of rotation (42) by force being introduced into a first actuating section (45), and wherein a second drive unit (5) of the two drive units (4, 5) can be driven to a second drive rotary movement (48) about a second axis of rotation (43) by force being introduced into a second actuating section (46), - wherein the first drive unit (4) has a first drive gear (55) with a first drive ring gear (55a) lying in a first ring gear plane (55b) extending transversely to the first axis of rotation (42) and wherein the second drive unit (5) has a second drive gear (56) with a second drive ring gear (56a) lying in a second ring gear plane (56b) extending transversely to the second axis of rotation (43), - wherein the ball head (8) of the second joint body (3) has on its outer circumferential surface (32) an output toothing (33) with which the drive tooth rings (55a, 56a) of the drive gears (55, 56) of both drive units (4, 5) are in positive-locking tooth engagement, characterized in that the two drive units (4, 5) are rotatable independently of each other, wherein the second axis of rotation (43) is perpendicular to the first axis of rotation (42), so that the second joint body (3) can be driven to the working swivel movement (6) by selectively rotating one or both drive units (4, 5) such that its main axis (12) is pivoted within a conical working area (62) about the pivoting center (7).

Description

[0001] The invention relates to a joint arrangement comprising a first joint body and a second joint body which is pivotable about a pivot center with respect to the first joint body in a working swivel movement and which can be positioned in different working swivel positions, wherein the first joint body has a ball socket in which the second joint body is rotatably mounted with a ball head about the pivot center to enable the working swivel movement, and wherein the second joint body has an imaginary principal axis which intersects the pivot center. - wherein two rotatable drive units are arranged on the first joint body, wherein a first drive unit of the two drive units can be driven to a first drive rotary movement about a first axis of rotation by force being introduced into a first actuating section, and wherein a second drive unit of the two drive units can be driven to a second drive rotary movement about a second axis of rotation by force being introduced into a second actuating section, - wherein the first drive unit has a first drive gear with a first drive ring gear lying in a first ring gear plane extending transversely to the first axis of rotation, and wherein the second drive unit has a second drive gear with a second drive ring gear lying in a second ring gear plane extending transversely to the second axis of rotation, - wherein the ball head of the second joint body has an output toothing on its outer circumferential surface with which the drive tooth rings of the drive gears of both drive units are in positive-locking tooth engagement.

[0002] A joint arrangement of this type, known from DE 10 2009 045 290 A1, is designed as a wobble ball joint and has a ball stud that is rotatable about the longitudinal axis of a housing. A spherical socket is formed in the housing, in which the ball stud is mounted with a ball bearing. The ball stud has a longitudinal axis that is inclined with respect to the longitudinal axis of the housing. A gear plate is formed on the ball bearing, with which two ball gears mesh, and with which a further gear plate also meshes. The further gear plate can be driven rotationally to introduce a torque into the ball stud via the two ball gears, causing the ball bearing to rotate and the ball stud to perform a wobbling motion.

[0003] A joint arrangement known from WO 2016 / 023568 A1 serves to articulate two device parts. A special feature of this known joint arrangement is that the second joint body is mounted without contact in a ball socket of the first joint body by means of a ball head. A superconductor is used to achieve this contactless mounting.

[0004] Joint assemblies are frequently used in robotics. An example of this is provided in DE 10 2010 013 617 B4. There, a joint assembly is integrated into a robot arm, for instance, to connect device components in the form of two arm sections of the robot arm. The known joint assembly also includes a drive unit that enables the two joint bodies to be driven into a relative rotational movement.

[0005] The invention is based on the objective of creating a simple and cost-effective joint arrangement with which a wide variety of relative movements between the joint bodies articulated to one another can be realized.

[0006] To solve this problem, in a joint arrangement of the type mentioned above, it is provided that the two drive units are rotatable independently of each other, with the second axis of rotation being perpendicular to the first axis of rotation, so that the second joint body can be driven to the working swiveling movement by selectively rotating one or both drive units in such a way that its main axis is swivelled within a conical working area around the swivel center.

[0007] This joint arrangement allows for a highly variable active pivoting and positioning of a second joint body, which is pivotally mounted on a first joint body. An actuating force can be introduced into each of the two drive units to produce a working pivoting movement of the second joint body through the interaction of the drive gears with the output teeth of the ball head. Each drive unit can produce a pivoting movement of the second joint body relative to the first joint body through the interaction of its drive gear with the output teeth of the ball head. This pivoting movement is directly the working pivoting movement when one drive unit is actuated individually, without simultaneously actuating the other drive unit.Simultaneous rotary actuation of both drive units generates a working swivel motion of the second joint body, composed of the two swivel movements that can be generated by each of the two drive units and which superimpose simultaneously. The two drive units can be actuated sequentially or simultaneously. They can also be actuated sequentially or simultaneously with different or identical rotational speeds and / or with different or identical directions of rotation. Effective and slip-free power transmission for generating the working swivel motion is ensured by the ball head's external circumferential surface, which features a toothed output shaft. Each drive unit engages with this shaft via its corresponding drive gear in a positive-locking mesh.The second joint body has an imaginary main axis that intersects the pivot center of the second joint body and can be pivoted within a conical working area around the pivot center during the working swivel movement. Accordingly, the second joint body can be positioned in different working swivel positions by means of a correspondingly controlled rotary actuation of the two drive units, in which the main axis lies within the aforementioned conical working area.

[0008] The joint arrangement can be used in any technical application where two device parts need to be connected by a joint and driven into a relative pivoting motion. A preferred application is robotics, where the joint arrangement is integrated, for example, once or multiple times, into a robot that has robot components capable of pivoting relative to each other.

[0009] Advantageous further developments of the invention are set out in the dependent claims.

[0010] Preferably, the joint arrangement is kinematically designed such that the main axis of the second joint body intersects an imaginary drive plane, regardless of the working swivel position of the second joint body. This imaginary drive plane is defined by the two rotation axes of the two drive units, which are arranged perpendicular to each other. Preferably, the pivot center for the working swivel movement lies directly in this drive plane.

[0011] Advantageously, each of the two drive units has a drive shaft passing through its associated drive gear. The longitudinal axis of each drive shaft coincides with the axis of rotation of its associated drive unit. Each drive shaft is coupled to its corresponding drive gear in a manner that enables torque transmission. Each drive gear is pivotally mounted on its associated drive shaft via a ball joint such that its gear plane can assume different inclinations with respect to the axis of rotation of the drive shaft, thereby enabling it to follow the changing inclination of the output gear teeth during the execution of the working swivel movement. In particular, the drive gear is pivotally mounted on its associated drive shaft in a manner similar to a swashplate.The mobility of the drive gear ensures low-wear and stress-free power transmission between the drive units and the ball head.

[0012] In each of the two drive units, the drive shaft expediently has a spherical bearing section with a spherical outer bearing surface on which the drive gear is pivotably mounted with a concave inner bearing surface, which is shaped in particular like a spherical zone. In this way, the drive gear can, in principle, perform any wobbling motion on the spherical bearing section. However, the relative movement between the drive gear and the drive shaft in the circumferential direction of the axis of rotation is restricted in order to enable torque transmission. For this purpose, at least one drive groove is formed in the outer bearing surface, extending in a plane coincident with the longitudinal axis of the drive shaft and preferably curved in its longitudinal direction. A drive projection of the drive gear, extending beyond the inner bearing surface, engages in this groove in a sliding and rotatable manner.This allows the drive gear to be pivoted variably relative to the drive shaft in order to adapt to the current working swivel position of the output gear formed on the ball head.

[0013] Preferably, the drive groove and the drive projection are present in pairs, being located in areas diametrically opposite each other with respect to the axis of rotation.

[0014] The arrangement of the drive groove and the drive projection with respect to the bearing section and the drive gear can also be reversed. In this case, at least one drive projection is located radially extending from the spherical bearing section, while a cooperating drive groove is formed in the preferably spherically zoned concave inner bearing surface of the drive gear.

[0015] Particularly for ease of assembly, it is advantageous if each drive gear consists of two gear halves mounted on the spherical bearing section from axially opposite sides and axially joined together, each forming a portion of the concave inner bearing surface. The two gear halves can be firmly connected to each other by any fasteners. For example, they can be snapped together, welded together, and / or bonded together.

[0016] The second joint body advantageously has an output shaft projecting radially from the ball head, the longitudinal axis of which coincides with the main axis of the second joint body. Such an output shaft is particularly well suited for connection to one of two device parts to be articulated together.

[0017] For the easy attachment of jointed device components, such as two robot components, it is advantageous to have a first mounting interface on the first joint body and a second mounting interface on the second joint body. The mounting interfaces allow for a secure mechanical connection. At least one, and preferably each, mounting interface is designed for external attachment of the associated joint body to a device component, particularly for screw fastening. However, each mounting interface can also be structured differently, for example, as a detachable clamping device.

[0018] To define a preferred configuration of the output gearing, it is advantageous to refer to a so-called great circle of the ball head that coincides with the main axis. The ball head has a plurality of such great circles, each lying within the region of a maximum diameter of the ball head. The spherical outer circumferential surface of the ball head has a circumferential direction, designated for clarity as the principal circumferential direction, which follows the circumference of such a great circle. The output gearing of the ball head has a plurality of teeth arranged successively in the principal circumferential direction, each with a longitudinal shape corresponding to the curvature of the ball head.

[0019] The teeth of the output gear can be designed so that they extend only over a partial circumference of the ball head. The essential aspect is an arrangement such that, regardless of the working swivel position, there is a gear mesh with the drive ring gears of both drive units.

[0020] It is considered particularly advantageous if the output toothing of the ball head is designed coaxially to the main axis, having a plurality of ring-shaped teeth which are arranged successively in an orientation coaxial to the main axis in the axial direction of the main axis.

[0021] Adjacent ring-shaped teeth of the output gear advantageously have different diameters. In particular, the diameter corresponds at least substantially to the outer diameter of the ball head in the plane in which the respective ring-shaped tooth extends. Each ring-shaped tooth is specifically designed as a circular ring. Between adjacent teeth, there is a ring-shaped interspace formed like an annular groove.

[0022] Preferably, the first joint body is designed in multiple parts, comprising a housing with two shell-shaped housing sections attached to and fastened against each other in the axial direction of an imaginary central longitudinal axis. The two shell-shaped housing sections are joined in a plane perpendicular to the central longitudinal axis and each forms a section of the ball socket. During assembly of the joint arrangement, the two shell-shaped housing sections can be attached to the ball head of the second joint body from opposite sides and connected to each other. The two housing sections are fastened to each other, for example, by a screw connection, particularly in a detachable manner.

[0023] If the joint assembly is intended for manual operation, for example as an articulated mounting base for workpieces, the actuating sections are designed for manual rotary force application. In this case, each actuating section can, for example, be equipped with a hand-operated and rotatable rotary knob.

[0024] A joint arrangement is considered particularly advantageous in which the actuating sections of the two drive units are designed for rotational force transmission by an electrically and / or fluid-driven drive unit of the joint arrangement. For example, a separate drive unit with its housing can be attached to the first joint body for each drive unit and coupled to the actuating section via an output shaft. The drive unit can be, for example, an electric motor, such as a servo motor or a stepper motor. The drive unit can also operate, for example, according to an electromagnetic principle.Another usable, fluid-powered drive device includes, for example, a pneumatically or hydraulically actuated working cylinder or at least one contraction drive that has a contraction hose which contracts axially when pressurized internally. The applicant markets such contraction drives under the name "Fluidic Muscle". This can be described as a pneumatic muscle.

[0025] The joint assembly preferably includes an electronic control unit to which the drive units are connected for operational electrical control. The electronic control unit can control the drive units to position the second joint body as desired.

[0026] It is advantageous if the second joint body not only has the degrees of freedom required to perform the working swivel movement, but is also rotatable relative to the first joint body about an axis of rotation coinciding with the main axis, referred to as the working axis of rotation. This rotational capability exists, in particular, independently of the working swivel movement and the currently assumed working swivel position. When the first joint body performs a rotational movement, its output teeth can slide off the two drive teeth without losing mesh.

[0027] Preferably, the joint arrangement includes a third drive unit by which the second joint body can be driven to a working rotary movement about the working axis of rotation.

[0028] Advantageously, the third drive unit is rotatably mounted on the first joint body about a third axis of rotation and has a third actuating section into which a drive force can be introduced to drive the third drive unit to a third drive rotation about the third axis of rotation. The third drive unit is connected to the second joint body via a linkage such that the third drive rotation of the third drive unit results in the desired working rotation of the second joint body about the working axis, which coincides with the main axis.

[0029] In this way, torque transmission for generating the working rotary motion of the second joint body is ensured regardless of which working swivel position the second joint body is currently assuming.

[0030] To generate the third drive rotary motion, the third actuation section is expediently designed in a comparable manner to the first and second actuation sections for manual rotary force application or for rotary force application by an electrically and / or fluid-driven drive device.

[0031] Preferably, the third drive unit is designed and arranged such that its third axis of rotation is aligned perpendicularly to a drive plane spanned by the first axis of rotation of the first drive unit and the second axis of rotation of the second drive unit.

[0032] A suitable embodiment of the third drive unit provides for a drive shaft with a third actuating section, which is rotatably mounted on the first joint body such that it can rotate about the third axis of rotation. The drive shaft, with a drive section, extends into a cavity of the ball head, and two coupling arms of the coupling mechanism are arranged on this drive section. These coupling arms are diametrically opposed to each other with respect to the third axis of rotation and project radially outwards in opposite directions. Each coupling arm has a coupling head on its end face facing away from the drive shaft, with which it engages in one of two coupling slots of the coupling mechanism. These slots are diametrically opposed with respect to the main axis and open into the cavity of the ball head.When the third drive unit rotates, the slot flanks of the coupling slots are acted upon by the coupling heads of the coupling arms, resulting in a torque transmission that generates the working rotary motion. Independently of this, the ball head is constantly tiltable, and particularly during the working swivel motion of the second joint body, about two mutually perpendicular first and second tilting axes. The first tilting axis is formed by the mutually coaxial longitudinal axes of the two coupling arms, and the second tilting axis runs perpendicular to a slot plane containing the two coupling slots.

[0033] The invention will now be explained in more detail with reference to the accompanying drawing. This drawing shows: Fig. 1 an isometric representation of a preferred embodiment of the joint arrangement according to the invention, Fig. 2 the joint arrangement Fig. 1 from a different perspective, Fig. 3 an isometric exploded view of the joint arrangement Fig. 1 and Fig. 2, Fig. 4 the joint arrangement according to Fig. 1 to 3 without illustration of the first joint body, Fig. 5 the arrangement from Fig. 4, wherein the second joint body and the third drive unit interacting with it are shown in longitudinal section, Fig. 6 a section of the joint arrangement according to section line VI-VI, wherein the section plane lies in a drive plane spanned by the perpendicularly aligned axes of rotation of the first and second drive unit, Fig. 7 a top view of the joint arrangement with viewing direction according to arrow VII from Fig. 8, where the first joint body is only partially shown, Fig. 8 the arrangement from Fig. 7 in a section according to section line VIII-VIII from Fig. 7, wherein the in Fig. 7. The component of the first joint body not shown is indicated by a dotted line, and Fig. 9 an isometric single view of the first drive unit in the from Fig. 7 evident operating phase with the first gear plane of the first drive gear inclined with respect to the first axis of rotation.

[0034] The joint arrangement, designated in its entirety by reference numeral 1, has a first joint body 2 and a second joint body 3 that is pivotable relative to the first joint body 2.

[0035] The joint assembly 1 has a first drive unit 4 and a separate second drive unit 5. Both drive units 4 and 5 are arranged on the first joint body 2. By actuating them, the second joint body 3 can be driven to a working swivel movement 6 relative to the first joint body 2, indicated by double arrows. The working swivel movement 6 has a swivel center 7.

[0036] As part of the working swivel movement 6, the second joint body 3 can be positioned in different swivel positions relative to the first joint body 2, which are referred to as working swivel positions.

[0037] To enable the working swivel movement 6, the second joint body 3 has a ball head 8 which is rotatably mounted in a ball socket 9 formed by the first joint body 2. The pivot point of the ball head 8, which is stationary with respect to the first joint body 2, lies at the pivot center 7, which is fixed with respect to the first joint body 2.

[0038] The second joint body 3 has an imaginary principal axis 12. The principal axis 12 intersects the pivot center 7 independently of the instantaneous working pivot position of the second joint body 3. Preferably, the principal axis 12 defines a longitudinal axis of the second joint body 3.

[0039] The first joint body 2 has an imaginary central longitudinal axis 13. Preferably, the first joint body 2 comprises a housing 11 with two shell-shaped first and second housing parts 14, 15, which are joined to one another in the axial direction of the central longitudinal axis 13 and together enclose a housing interior 16. The inner surfaces of the housing parts 14, 15, which are each shaped like a spherical cap and define the spherical socket 9, which is shaped according to the inner contour of a hollow sphere.

[0040] Each of the two shell-shaped housing parts 14, 15 has a spherical recess. These two spherical recesses form the housing interior 16 when the housing parts 14, 15 are positioned against each other with the openings of the housing recesses facing forward. The two housing parts 14, 15 abut each other in a joining plane 17 that is perpendicular to the central longitudinal axis. The two housing parts 14, 15 are firmly connected to each other by fastening screws or other fastening means.

[0041] The first housing part 14 has a first housing opening 18 that opens into the housing interior 16. The longitudinal axis of this first housing opening 18 coincides with the central longitudinal axis 13 of the first joint body 2.

[0042] The second joint body 3 advantageously has an output shaft 22 projecting radially from the ball head 8 and aligned coaxially with the main axis 12. It is exemplarily designed as a hollow cylinder, but can also consist at least partially of solid material. The output shaft 22 has a longitudinal axis 23 that coincides with the main axis 12.

[0043] The second joint body 3 is preferably designed in two parts. This applies to the illustrated embodiment. Here, the second joint body 3 consists of the ball head 8 and a T-shaped profiled output body 24, which is attached to the ball head 8 and has the output nozzle 22.

[0044] The second joint body 3 protrudes from the first joint body 2 through the first housing opening 18 with its output nozzle 22. The cross-section of the first housing opening 18 is significantly larger than that of the output nozzle 22. Thus, an annular clearance remains between the outer circumference of the output nozzle 22 and the boundary surface of the first housing opening 18, enabling the working swivel movement 6.

[0045] The ball head 8 expediently has a cavity 25. For example, the ball head 8 is penetrated by the cavity 25 in the axial direction of the main axis 12. The two resulting outlet openings of the cavity 25 are designated as the first and second ball openings 26 and 27. The first ball opening 26 is associated with the first housing opening 18.

[0046] As an example, the output body 24 is inserted into the first ball opening 26 with an annular mounting section 28 that projects radially beyond the output nozzle 22 and is fastened to the ball head 8 by suitable means. For example, a snap-fit ​​connection or a welded connection is used.

[0047] The second ball opening 27 faces the first housing part 14.

[0048] The ball head 8 has a toothed output 33 on its spherical outer circumferential surface 32. This toothed output 33 is arranged coaxially with the main axis 12. It has a plurality of ring-shaped teeth 34, which are arranged successively in an orientation coaxial with the main axis 12 and in the axial direction of the main axis 12. For the sake of simplicity, the axial direction of the main axis 12 will in the following also be referred to as the main axis direction 12.

[0049] Between teeth 34 that are immediately consecutive in the main axis direction 12, there is an annular tooth gap 35 that is also coaxial with the main axis 12. Each annular tooth gap 35 has the form of an annular groove.

[0050] If the spherical head 8 is conceptually cut in a plane coinciding with the principal axis 12, the cross-sectional area is bounded by a so-called great circle 36 of the sphere, which is in Fig. 8 is indicated by a dashed line. For the purposes of this analysis, the openings in the outer contour of the ball head 8 resulting from the spherical openings 26, 27 are disregarded. A circumferential direction that follows the circumference of the great circle 36 shall be referred to below as the principal circumferential direction 37 of the ball head 8. In this principal circumferential direction 37, the teeth 34 and the interspaces 35 are formed alternately on the outer circumferential surface 32 of the ball head 8.

[0051] The ring-shaped teeth 34 and the interdental spaces 35 are each preferably designed in a circular shape.

[0052] Each ring-shaped tooth 34 extends in a tooth plane perpendicular to the main axis 12. Each tooth 34 has a curved longitudinal shape in the tooth plane, the curvature corresponding to the radius of the ring shape of the respective tooth 34.

[0053] The ring-shaped teeth 34 have their smallest diameter in the region of the two spherical openings 26, 27. From there, the ring diameter of the teeth 34 becomes increasingly larger and reaches a maximum in the equatorial region of the spherical head 8.

[0054] The two drive units 4 and 5 mentioned above are mounted on the first joint body 2 in an independently rotatable manner. For example, they are rotatably mounted on the housing 11. The first drive unit 4 is rotatable about a first axis of rotation 42, and the second drive unit 5 is rotatable about a second axis of rotation 43. The two axes of rotation 42 and 43 are perpendicular to each other and run approximately tangentially to the outer circumferential surface 32 of the ball head 8. Together, the two axes of rotation 42 and 43 define a plane, designated as the drive plane 44, which is perpendicular to the central longitudinal axis 13. This drive plane 44 is transversely intersected by the main axis 12 of the second joint body 3, regardless of the current working swivel position of the second joint body 3.

[0055] The first drive unit 4 has a first actuating section 45 and the second drive unit 5 has a second actuating section 46. Both actuating sections 45, 46 are located outside the first joint body 2 and allow force to be applied to generate a torque to drive the first drive unit 4 to a first drive rotary movement 47 about the first axis of rotation 42 and to drive the second drive unit 5 to a second drive rotary movement 48 about the second axis of rotation 43.

[0056] Advantageously, each drive unit 4, 5 has a drive shaft 52 which is rotatably mounted on the first joint body 2 about its longitudinal axis 54 by means of rotary bearing means 53, wherein the respective longitudinal axis 54 defines the associated axis of rotation 42, 43. Preferably, the end section of each drive shaft 52 located outside the first joint body 2 functions as an actuating section 45, 46.

[0057] The first drive unit 4 has a first gear 55 with a peripheral first drive ring gear 55a. The second drive unit 5 has a second drive gear 56 with a peripheral second drive ring gear 56a. The drive ring gears 55a, 56a are formed radially outside the respective drive gears 55, 56. The first drive ring gear 55a lies in an imaginary first ring gear plane 55b, while the second drive ring gear 56a lies in a second ring gear plane 56b.

[0058] The first drive gear 55 is fixedly mounted on the drive shaft 52 of the first drive unit 4. The second drive gear 56 is fixedly mounted on the drive shaft 52 of the second drive unit 5. Both drive gears 55 and 56, with their drive teeth 55a and 56a, mesh with the output teeth 33 of the ball head 8. The meshing areas are offset from each other by 90° in the circumferential direction of the main axis 12.

[0059] The joint assembly 1 expediently has a first drive unit 57 that acts on the first actuating section 45, and it also has a second drive unit 58 that acts on the second actuating section 46. By means of the drive units 57, 58, each drive shaft 52, and thus each drive unit 4, 5, can be driven either clockwise or counterclockwise to the associated first or second drive rotary motion 47, 48.

[0060] The drive devices 57, 58 are, for example, electric drive devices 57, 58, preferably based on an electromechanical or electromagnetic drive principle. Alternatively, they can also be of a fluid-actuated design. In all these cases, it is advantageous if the joint arrangement also includes an electronic control unit (not illustrated) to which the drive devices 57, 58 are connected to receive control signals in order to generate the drive rotary movements 47, 48.

[0061] Additionally or alternatively, the actuation sections 45, 46 can also be designed for manual force application.

[0062] For example, a hand knob that can be rotated with one hand can be fixed in a rotationally fixed manner on each actuation section 45, 46.

[0063] Due to the described gear engagement, the second joint body 3 can be driven to the working swivel movement 6 by selectively rotating one or both drive units 4, 5. Selective rotation includes rotating only one of the two drive units at a given time or rotating both drive units simultaneously. Furthermore, selective rotation encompasses optional clockwise or counterclockwise rotation, as well as rotation at different speeds.

[0064] When a drive unit 4, 5 is rotated, its drive gear 55, 56 rotates accordingly, whereby the gear mesh with the output gear 33 results in a torque being introduced into the ball head 8, which causes the first joint body 2 to pivot about the pivot center 7. The output gear 33 passes by the currently rotating drive gear 55, 56.

[0065] The working swivel motion 6 can be generated by a correspondingly coordinated rotation of the two drive units 4, 5, whereby the main axis 12 moves within a Fig. 1. The conical working area 62, indicated by a dash, is pivoted around the pivoting center 7.

[0066] Preferably, the drive gears 55, 56 are mounted such that they are pivotable relative to the first joint body 2 in such a way that their gear rim planes 55b, 56b can assume different inclinations relative to the associated axis of rotation 42, 43. This allows the drive gears 55, 56 to automatically adjust their orientation to the instantaneous inclination of the output gear 33. The mounting can be compared to that of a swashplate. This automatic adjustability of the meshing gears reduces wear and prevents jamming. Furthermore, this ensures a relatively large contact area between the adjacent tooth flanks, which minimizes the specific stress.

[0067] To enable the aforementioned tilt adjustment, it is advantageous if each drive gear 55, 56 has a central axial opening 63 with which it is mounted on the associated drive shaft 52. This allows the drive gear 55, 56 to pass through the associated drive shaft 52. To facilitate the aforementioned tilt adjustment, the drive gear 55, 56 is mounted on the drive shaft via a ball joint 64.

[0068] Advantageously, to form each ball joint 64, each drive shaft 52 is provided with a spherical bearing section 65 on which the drive gear 55, 56 is pivotably mounted with an inner bearing surface 66 that radially defines the axial opening 63 on the outside, wherein this inner bearing surface 66 is concave and shaped like the spherical zone of a hollow sphere. The spherical bearing section 65 has a spherical outer bearing surface 61 that is complementary to the inner bearing surface 66.

[0069] For ease of assembly, each drive gear 55, 56 expediently consists of two axially joined and fastened annular gear halves 67a, 67b, which, during assembly of the drive unit 4, 5, are placed onto the drive shaft 52 from axially opposite sides and attached to the spherical bearing section 65. Each of the two gear halves 67a, 67b defines a portion of the concave inner bearing surface 66.

[0070] Preferably, the two gear halves 67a, 67b are provided with a centering device 68 which prevents the joined gear halves 67a, 67b from rotating relative to each other by means of a positive fit. The centering device 68 consists, for example, of several centering pins engaging in centering recesses.

[0071] The two gear halves 67a, 67b are held together axially by suitable fastening measures, for example by locking, by gluing or by welding.

[0072] For the aforementioned torque transmission between the drive shaft 52 and the drive gear 55, 56, two drive grooves 72 are provided in the outer bearing surface 61 of the spherical bearing section 65. The drive grooves 72 are diametrically opposed to each other with respect to the longitudinal axis 54 and extend in a plane that coincides with the longitudinal axis 54 of the drive shaft 52. The longitudinal groove opening of each drive groove 72 follows the curvature of the spherical outer bearing surface 61. Accordingly, each drive groove 72 is preferably curved in its longitudinal direction.

[0073] Each drive gear 55, 56 has two diametrically opposed drive projections 73, which extend radially inwards into the central axial opening 63. One of these two drive projections 73 engages in each of the two drive grooves 72. The engagement is both sliding and rotational.

[0074] When a drive rotary movement 47, 48 is executed, the drive projections 73 are acted upon by the groove flanks of the drive groove 72, so that a rotary drive of the associated drive gear 55, 56 takes place. Independently of this, each drive gear 55, 56 is able to pivot by changing the inclination of the gear plane 55b, 56b, whereby the preferably circularly contoured drive projections 73 slide along in the drive groove 72 or are rotated in this respect.

[0075] To change the inclination of the gear ring plane 55b, 56b, each drive gear 55, 56 can be rotated about an axis of rotation defined by the coaxial longitudinal axes of the two drive projections 73. Furthermore, each drive gear 55, 56 can be pivoted about an axis of rotation perpendicular to this axis of rotation. Since the pivoting movements can be superimposed, each drive gear 55, 56 can perform a change in the inclination of the gear ring plane 55b, 56b similar to a swashplate.

[0076] It is understood that the arrangement of the drive slots 72 and the drive projections 73 with respect to the drive shaft 52 and the drive gears 55, 56 can also be reversed. Furthermore, the drive slots 72 and drive projections 73 could also be present only once per ball joint 64.

[0077] The two drive units 4, 5 expediently extend within a drive chamber 74 defined by the first joint body 2 or by the housing 11. Accordingly, two such drive chambers 74 are provided. Each drive chamber 74 intersects the ball socket 9, so that a housing window 75 is provided through which a respective drive gear 55, 56 can engage with the output gear 33.

[0078] The walls of the drive chambers 74 are expediently formed partially by one of the two housing parts 14, 15, which for this purpose have shell-shaped wall sections.

[0079] The joint arrangement 1 is expediently provided with means that enable independent external mechanical fastening of the two joint bodies 2, 3.

[0080] In this context, the first joint body 2 is provided with a first fastening interface 76 and the second joint body 3 with a second fastening interface 77. Both fastening interfaces 76 and 77 are designed to enable a screw connection with an external device component (not shown), for example, a section of a robot arm. The first fastening interface 76 consists of fastening holes formed in the first joint body 2, while the second fastening interface 77 consists of an internal thread formed in the output nozzle 22.

[0081] It is understood that the fastening interfaces 76, 77 which enable a mechanical connection with external device parts can be designed according to the respective requirements.

[0082] Advantageously, the second joint body 3 has an additional degree of freedom relative to the first joint body 2. This additional degree of freedom consists of a rotational movement about an axis of rotation coinciding with the main axis 12, which, for clarity, is referred to as the working axis of rotation 78. The second joint body 3 can perform a rotational movement about the working axis of rotation 78, regardless of its working pivot position and even during the execution of a working pivot movement 6. This rotational movement is referred to below, for clarity, as the working rotational movement 82. The working rotational movement 82 is possible in both clockwise and counterclockwise directions.

[0083] The two drive gear rings 55a, 56a are in meshing with the output gear 33 in every operating state of the joint arrangement 1, and thus also during a working rotary movement 82. During this working rotary movement 82, the output gear 33, which follows this working rotary movement 82, can slide off the gear ring sections of the two drive gear rings 55a, 56a with which it is currently in meshing.

[0084] It is advantageous if the working rotary motion 82 can be initiated and controlled as required. For this purpose, the joint arrangement 1 is preferably equipped with a third drive unit 83, which is rotaryally coupled to the second joint body 3. The third drive unit 83 is not only capable of generating the working rotary motion 82, but can also hold the second joint body 3 rotationally fixed in any rotational position with respect to the working axis of rotation 78.

[0085] The third drive unit 83, like the first and second drive units 4, 5, is rotatably mounted on the first joint body 2 about a third axis of rotation 84, which preferably coincides with the central longitudinal axis 13 of the first joint body 2. Accordingly, in the exemplary embodiment, the third axis of rotation 84 is perpendicular to the drive plane 44.

[0086] The third drive unit 83 has a third actuating section 85 accessible from outside the first joint body 2, into which an actuating force suitable for generating a torque can be introduced, by which the third drive unit 83 can be driven to a third drive rotary movement 86 about the third axis of rotation 84, indicated by a double arrow.

[0087] The third drive unit 83 is coupled to the first joint body 2 via a coupling gear 87 in such a way that the third drive rotary movement 86 of the third drive unit 83 results in the working rotary movement 82 of the second joint body 3 about the working axis 78.

[0088] Advantageously, the joint arrangement 1 is equipped with a third drive unit 88, shown only schematically, which is coupled to the third actuating section 85 and is capable of generating the third drive rotary movement 86. Preferably, the third drive unit 88, like the other two drive units 57 and 58, is mounted externally on the first joint body 2. The descriptions of the third drive unit 88 given above for the other two drive units 57 and 58 apply accordingly.

[0089] The third drive unit 88 is also expediently connected to an optional electronic control unit that controls the operation of the third drive unit 88. It is also possible to additionally or alternatively design the third actuation section 85 for manual rotary force application and, for example, to equip it with a manually operated rotary knob.

[0090] The third actuating section 85 is advantageously formed on a drive shaft 92, which is rotatably mounted on the first joint body 2 about the third axis of rotation 84, with the third actuating section 85 lying outside the first joint body 2. The shell-shaped second housing part 15 has a second housing opening 19 opposite the first housing opening 18 of the first housing part 14 in the axial direction of the central longitudinal axis 13, which is rotatably traversed by the drive shaft 92. An inner end section of the drive shaft 92, which is designated as the drive section 93, projects into the interior of the housing 16 and also into the cavity 25 of the ball head 8.

[0091] The coupling gear 87 has two coupling arms 94 arranged on the drive section 93, diametrically opposed to each other with respect to the third axis of rotation 84, each ending with a coupling head 95.

[0092] The coupling mechanism 87 also includes two coupling slots 96, which are formed on the inner circumference of the wall of the ball head 8 enclosing the cavity 25 and open into this cavity 25 with a slot-like longitudinal opening. The two coupling slots 96 are diametrically opposed to each other with respect to the main axis 12 and each extends in the direction of the main axis 12, lying in a common slot plane 97 containing the main axis 12. As can be seen in particular from Fig. As can be clearly seen in Figure 5, the coupling slots 96 expediently have a concavely curved slot base 98, so that they each have a groove-like structure and could also be referred to as coupling grooves. The curvature of the slot base 98 preferably corresponds to the curvature of the outer circumferential surface 32 of the ball head 8.

[0093] The two coupling arms 94 have coaxial longitudinal axes 94a. Each coupling arm 94, with its coupling head 95, engages in one of the two coupling slots 96 and rests against both groove flanks of the respective coupling slot 96. Furthermore, each coupling head 95 is slidably mounted in its associated coupling slot 96, allowing it to slide along the longitudinal direction of the slot.

[0094] The drive torque for generating the working rotary motion 82 is transmitted by the coupling gear 87 from the third drive unit 83 to the second joint body 3 by the coupling heads 95 pressing on the slot flanks of the coupling slots 96 in the circumferential direction of the main axis 12.

[0095] The coupling heads 95 are also designed such that the second joint body 2 can be tilted relative to the third drive unit 83 about a first tilting axis 99, this first tilting axis 99 coinciding with the two coaxial longitudinal axes 94a of the two coupling arms 94. The tilting mobility is facilitated by the fact that the coupling heads 95 are spherically rounded in the contact area with the support flanks of the coupling slots 96. Preferably, the coupling heads 95 are entirely spherical.

[0096] If the coupling heads 95 are separate elements of the coupling arms 94, the tilting mobility about the first tilting axis 99 can also be facilitated by the coupling heads 95 being rotatably mounted with respect to the longitudinal axes 94a on the arm section of the associated coupling arm 94 connected to the drive section 93. Particularly in such a rotatable configuration, the coupling heads 95 can also be provided with a circular cylindrical contour on the outside.

[0097] Due to the described design, the second articulated body 3 is able to tilt about the first tilting axis 99 relative to the third drive unit 83 during the execution of the working swivel movement 6. The tilting movement 99a that takes place is indicated by a double arrow.

[0098] In addition, the first joint body 2 can also tilt about a second tilting axis 100 by performing a second tilting movement 100a. This second tilting axis 100 is perpendicular to the first tilting axis 99 and intersects both the first tilting axis 99 and the central longitudinal axis 13. The point of intersection is advantageously located at the pivot center 7.

[0099] During the second tilting movement 100a, the coupling slots 96 move along the coupling heads 95, sliding off them with their slot flanks.

[0100] The two tilting movements 99a, 100a can occur simultaneously. The tilting mobility allows the second joint body 3 to perform the working swivel movement 6 and to be continuously coupled to the third drive unit 83.

Claims

[1] Joint arrangement comprising a first joint body (2) and a second joint body (3) which is pivotable about a pivot center (7) with respect to the first joint body (2) by performing a working swivel movement (6) and which can be positioned in different working swivel positions, wherein the first joint body (2) has a ball socket (9) in which the second joint body (3) is rotatably mounted with a ball head (8) about the pivot center (7) to enable the working swivel movement (6), and wherein the second joint body (3) has an imaginary principal axis (12) which intersects the pivot center (7), - wherein two rotatable drive units (4, 5) are arranged on the first joint body (2), wherein a first drive unit (4) of the two drive units (4, 5) can be driven to a first drive rotary movement (47) about a first axis of rotation (42) by force being introduced into a first actuating section (45), and wherein a second drive unit (5) of the two drive units (4, 5) can be driven to a second drive rotary movement (48) about a second axis of rotation (43) by force being introduced into a second actuating section (46), - wherein the first drive unit (4) has a first drive gear (55) with a first drive ring gear (55a) lying in a first ring gear plane (55b) extending transversely to the first axis of rotation (42) and wherein the second drive unit (5) has a second drive gear (56) with a second drive ring gear (56a) lying in a second ring gear plane (56b) extending transversely to the second axis of rotation (43), - wherein the ball head (8) of the second joint body (3) has on its outer circumferential surface (32) an output toothing (33) with which the drive toothing rings (55a, 56a) of the drive gears (55, 56) of both drive units (4, 5) are in positive tooth engagement, characterized by, that the two drive units (4, 5) are rotatable independently of each other, wherein the second axis of rotation (43) is perpendicular to the first axis of rotation (42), so that the second articulated body (3) can be driven to the working swivel movement (6) by selectively rotating one or both drive units (4, 5) such that its main axis (12) is swivelled within a conical working area (62) around the swivel center (7). [2] Joint arrangement according to claim 1, characterized by , that the main axis (12) of the second joint body (3) intersects a drive plane (44) spanned by the mutually perpendicular rotation axes (42, 43) of the two drive units (4, 5), regardless of the respective working swivel position. [3] Joint arrangement according to claim 1 or 2, characterized by, that each of the two drive units (4, 5) has a drive shaft (52) passing through the associated drive gear (55, 56), the longitudinal axis (54) of which coincides with the associated axis of rotation (42, 43) and which is coupled to the drive gear (55, 56) in a torque-transmitting manner, wherein the drive gear (55, 56) is pivotably mounted on the drive shaft (52) via a ball joint (64) such that its gear plane (55b, 56b) can assume different inclinations with respect to the axis of rotation (42, 43) and can thereby follow the output gear (33) which changes in inclination during the working swivel movement (6). [4] Joint arrangement according to claim 3, characterized by, that each drive shaft (52) has a spherical bearing section (65) with a spherical outer bearing surface (61) on which the drive gear (55, 56) is pivotably mounted with a spherically zoned concave inner bearing surface (66), wherein at least one curved drive groove (72) extending in a plane coinciding with the longitudinal axis (54) of the drive shaft (52) is formed in the outer bearing surface (61), into which a drive projection (73) of the drive gear (55, 56) projecting beyond the inner bearing surface (66) engages in a sliding and rotatable manner, or vice versa. [5] Joint arrangement according to claim 4, characterized by , that each drive gear (55, 56) consists of two gear halves (67a, 67b) placed on the spherical bearing section (65) from axially opposite sides and axially joined together, each forming a part of the concave inner bearing surface (66). [6] Joint arrangement according to any one of claims 1 to 5, characterized by , that the second joint body (3) has an output nozzle (22) projecting radially from the ball head (8) and coaxial with the main axis (12). [7] Joint arrangement according to any one of claims 1 to 6, characterized by , that a first fastening interface (76) for external fastening of the first joint body (2) is formed on the first joint body (2), wherein a second fastening interface (77) for external fastening of the second joint body (3) is formed on the second joint body (3). [8] Joint arrangement according to any one of claims 1 to 7, characterized by, that the outer circumferential surface (32) of the ball head (8) has a principal circumferential direction (37) which follows the circle of a great circle (36) of the ball head (8) which coincides with the principal axis (12), wherein the output toothing (33) of the ball head (8) has a plurality of teeth (34) which are arranged successively in the principal circumferential direction (37) and each have a curved longitudinal shape transverse to it. [9] Joint arrangement according to any one of claims 1 to 8, characterized by , that the output toothing (33) of the ball head (8) is designed coaxially to the main axis (12), having a plurality of ring-shaped teeth (34) which are arranged successively in an orientation coaxial to the main axis (12) in the axial direction of the main axis (12). [10] Joint arrangement according to any one of claims 1 to 9, characterized by, that the first joint body (2) has an imaginary central longitudinal axis (13) and has two shell-shaped housing parts (14, 15) attached to one another, which are joined in a joining plane (17) perpendicular to the central longitudinal axis (13) and each form a section of the ball socket (9). [11] Joint arrangement according to any one of claims 1 to 10, characterized by , that the actuating sections (45, 46) of the two drive units (4, 5) are each designed for manual rotary force application and / or for rotary force application by an electrically and / or fluid force operated drive device (57, 58) of the joint arrangement (1). [12] Joint arrangement according to any one of claims 1 to 11, characterized by, that the second joint body (3) is rotatable relative to the first joint body (2) about a working axis of rotation (78) that coincides with the main axis (12), independently of the working swivel movement (6) and its instantaneous working swivel position, wherein the output toothing (33) can slide on the two drive tooth rings (55a, 56a). [13] Joint arrangement according to claim 12, characterized by , that it has a third drive unit (83) rotatably mounted on the first joint body (2) about a third axis of rotation (84), which can be driven by force being introduced into a third actuating section (85) to a third drive rotary movement (86) about the third axis of rotation (84) and which is in drive connection with the second joint body (3) via a linkage (87) such that the third drive rotary movement (86) of the third drive unit (83) results in a working rotary movement (82) of the second joint body (3) about the working axis of rotation (78). [14] Joint arrangement according to claim 13, characterized by , that the third actuation section (85) of the third drive unit (83) is designed for manual rotary force application and / or for rotary force application by an electrically and / or fluid force operated drive device (88) of the joint arrangement (1). [15] Joint arrangement according to claim 13 or 14, characterized by , that the third axis of rotation (84) of the third drive unit (83) is aligned perpendicularly to a drive plane (44) spanned by the first axis of rotation (42) of the first drive unit (4) and the second axis of rotation (43) of the second drive unit (5), [16] Joint arrangement according to any one of claims 13 to 15, characterized by, that the third drive unit (83) has a drive shaft (92) having the third actuating section (85), rotatably mounted on the first joint body (2) about the third axis of rotation (84), which with a drive section (93) immerses into a cavity (25) of the ball head (8), wherein on the drive section (93) two coupling arms (94) of the coupling mechanism (87) are arranged diametrically opposite to each other with respect to the third axis of rotation (84) and projecting radially outwards in opposite directions, each of which with a coupling head (95) immerses into one of two coupling slots (96) of the coupling mechanism (87) which are diametrically opposite to each other with respect to the main axis (12) and open into the cavity (25) of the ball head (8),wherein the coupling heads (95) of the coupling arms (94) cooperate with the slot flanks of the coupling slots (96) for torque transmission between the third drive unit (83) and the second joint body (3), and wherein the ball head (8) of the second joint body (3) is tiltable about two mutually perpendicular first and second tilting axes (99, 100) during the working swivel movement (6) of the second joint body (3), wherein the first tilting axis (99) is formed by the mutually coaxial longitudinal axes (94a) of the two coupling arms (94), and the second tilting axis (100) is perpendicular to a slot plane (97) containing the two coupling slots (96).

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