Three-legged joint and inner joint part of three-legged joint

Abstract

The invention relates to a tripod joint (1) which at least comprises an outer joint part (2), an inner joint part (3) and a plurality of rotating bodies (4), wherein the outer joint part (2) has a receptacle (6) for the inner joint part (3), which receptacle extends along a first axis of rotation (5), and three guide rails (9), which guide rails extend along the first axis of rotation (5) and are arranged distributed in the circumferential direction (7, 8), the inner joint part (3) has a central body (11) extending along the second rotational axis (10) and three journals (14) extending from the central body (11) in the radial direction (12), each having a journal axis (13) and arranged distributed in the circumferential direction (7, 8); wherein one of the rotating bodies (4) is arranged on each journal (14), the inner peripheral surface (15) of which is in contact with the journal (14) and the outer peripheral surface (16) of which is in contact with the respective guide rail (9). The invention further relates to an inner joint part (3).

Description

Technical Field

[0001] The present invention relates to a tripod joint and an inner joint component of the tripod joint, and in particular to an inner joint component of the tripod joint. Background Art

[0002] The tripod joint usually comprises at least one outer joint part with a first rotation axis and an inner joint part with a second rotation axis. The inner joint part comprises a central body with three molded journals. Rotating bodies are arranged on the journals accordingly. The inner joint part can be displaced along the first rotation axis in particular relative to the outer joint part. Further, the inner joint part can be deflected relative to the outer joint part, that is to say, the first rotation axis and the second rotation axis can be arranged relative to each other at a so-called deflection angle.

[0003] Such a joint is known, for example, from WO 2009 / 052857 A1. The outer joint part comprises a longitudinal axis (first rotation axis) and a hollow space (receiving portion) with at least one open end extending along the longitudinal axis, wherein three recesses (guide rails) extending parallel to the longitudinal axis are constructed in the outer joint part. The inner joint part comprises a (own) longitudinal axis (second rotation axis) and a central body, on which three journals are molded, each of which has a journal axis extending radially from the longitudinal axis. A rotating body is arranged on each journal. Each rotating body is longitudinally movably accommodated in a corresponding recess of the outer joint part. The rotating body can be arranged at the journal by a supporting body (rolling body) or by an additional inner ring. The rotating body in particular comprises at least one outer ring and a supporting body, and if possible, an inner ring, wherein a supporting body is arranged between the outer ring and the inner ring.

[0004] The applicant has been manufacturing and selling tripod joints for a long time, for example under the name of AAR tripod joint. The AAR tripod joint is used in particular on the sideshafts of motor vehicles, which serve for the drive connection between the differential and the drive wheels. In this case, a so-called constant velocity ball joint is usually used on the wheel side and the AAR tripod joint cited here is used as a sliding joint at the differential. The AAR tripod joint is designed in particular for deflection angles of 23 to 26 degrees (or less) in size.

[0005] The journal contacts the inner ring of the bearing or rotating body via a so-called sliding surface (contact surface), which is in particular designed in the form of a spherical segment. The sliding surface is oriented in the circumferential direction, so that the torque acting about the longitudinal axis of the joint is transmitted via the sliding surface of the journal to the rotating body and from the rotating body to the recess (or vice versa).

[0006] In traction operation of the motor vehicle, that is, when the motor vehicle is driven by the drive unit, the journal contacts the rotor with one of the sliding surfaces and the rotor contacts only one side of the recess. In coasting operation or cruising operation of the motor vehicle, that is, when the drive torque is introduced from the wheel and the drive unit is further engaged (coasting) or disengaged (coasting), the journal contacts the rotor with the other sliding surface and the rotor contacts only the other side of the recess. In coasting operation or cruising operation, the direction of the introduced torque and the direction of rotation of the joint are opposite to each other, while in traction operation they are in the same direction.

[0007] In order to achieve particularly advantageous guiding properties, an offset is provided between a first pitch circle radius of the sliding surface of the journal and a second pitch circle radius of the recess.

[0008] The pitch radius of the journal is the so-called effective radius. In the case of elongated joints, it is defined, that is, the longitudinal axis or the axis of rotation is arranged coaxially relative to one another. The effective radius defines the lever arm of the object that generates the force when transmitting torque. In other words, the pitch radius of the journal is the radius, starting from the longitudinal axis of the inner joint part, on which, in the case of elongated joints, for example, the center point of the spherical segment-shaped sliding surface of the journal is arranged.

[0009] The pitch radius of the outer joint part or the recess is also the so-called effective radius, which in the case of an elongated joint is defined, that is, the longitudinal axis or the axis of rotation is arranged coaxially relative to one another. The effective radius defines the lever arm of the object that generates the force when transmitting the torque.

[0010] The definition of the pitch circle radius (also referred to as pitch circle radius—PCR) is generally known, in particular also for tripod joints.

[0011] That is to say, the deviation of the pitch circle radii is the difference between the pitch circle radii.

[0012] The performance of a tripod joint is defined in particular by the so-called ACFG value (Axial Cyclic Force Generation, i.e. the undesired axial forces generated by the joint). The value is specified as the root mean square value of the force in Newton root mean square [Nrms]. The value varies depending on the deflection angle of the joint, wherein the course of the value can be defined or determined depending on the deflection angle for each joint. The area of ​​use of the joint is thus limited to the maximum deflection angle at which the ACFG value does not exceed a value that is still considered permissible. Summary of the invention

[0013] The object of the present invention is to at least partially solve the problems described with respect to the prior art. In particular, a tripod joint or an inner joint part of a tripod joint should be proposed, which has particularly advantageous properties with respect to the ACFG value.

[0014] A tripod joint with the features according to patent claim 1 and an inner joint part with the features according to patent claim 10 contribute to achieving this object. Advantageous developments are the subject matter of the dependent patent claims. The features cited individually in the patent claims can be combined with one another in a technically meaningful manner and can be supplemented by details of the facts explained in the description and / or the drawings, wherein further embodiments of the invention are explained.

[0015] A tripod joint (also referred to as joint below) is proposed, which comprises at least an outer joint part and an inner joint part and a plurality of rotating bodies. The tripod joint is in particular a sliding joint, wherein the inner joint part can slide relative to the outer joint part along a first rotation axis.

[0016] The outer joint part has a receptacle for the inner joint part extending along the first rotational axis and three guide rails extending along the first rotational axis and arranged (uniformly) distributed in the circumferential direction.

[0017] The inner joint part has a central body extending along the second rotational axis and three journals extending in the radial direction from the central body, each having a journal axis and arranged (uniformly) distributed in the circumferential direction.

[0018] A rotating body is arranged on each journal, which contacts the journal with its inner peripheral surface and contacts the corresponding guide rail with its outer peripheral surface. Each journal has a contact surface for contacting the inner peripheral surface, wherein the first contact surface is oriented at least in a first peripheral direction and the second contact surface is oriented at least in a second peripheral direction pointing opposite to the first peripheral direction. When the rotation axes are arranged coaxially relative to each other, the first contact surface has a first pitch circle radius, the second contact surface has a second pitch circle radius, and the guide rail has a third pitch circle radius, wherein at least the first pitch circle radius and the second pitch circle radius have different values ​​from each other.

[0019] The outer peripheral surface of the rotating body can be twisted in particular relative to the inner peripheral surface of the rotating body. The inner peripheral surface can be formed, for example, by an inner ring or by rolling bodies, which are in contact with the journal or the contact surface. If the inner peripheral surface is formed by an inner ring, rolling bodies are arranged between the inner ring and the outer peripheral surface so that relative twisting is possible.

[0020] The twisting of the inner peripheral surface relative to the outer peripheral surface enables the rotating body to slide down along the guide rail, so that the inner joint part can slide relative to the outer joint part along the first rotation axis.

[0021] When the inner joint part is pivoted, the rotating body is further guided via the guide rail, wherein at least the bearing journal pivots relative to the rotating body.

[0022] In this case, the rotating body is guided in particular by means of the guide rail in such a way that the rotating body cannot pivot relative to the guide rail.

[0023] Alternatively, in the event of a pivoting of the inner joint part, the rotary body also pivots relative to the guide rail.

[0024] In particular, the inner circumferential surface and the outer circumferential surface do not execute any further relative movements relative to one another, apart from a relative rotation.

[0025] The pitch radius of the journal, as defined above, is in particular the so-called effective radius. This is defined in the case of an elongated joint, that is, the axes of rotation are arranged coaxially relative to one another. The effective radius defines the lever arm of the object that generates the force when transmitting the torque. In other words, the pitch radius of the journal is the radius, starting from the second axis of rotation, on which, in the case of an elongated joint, the center point of the spherical segment-shaped sliding surface of the journal is arranged, for example.

[0026] The pitch radius of the outer joint part or guide rail, as defined above, is the so-called effective radius, which in the case of an elongated joint is defined, that is, the longitudinal axis or the axis of rotation is arranged coaxially relative to one another. The effective radius defines the lever arm of the object that generates the force when transmitting the torque.

[0027] In this case, the pitch circle radius defines in particular a spherical surface (of a journal or an outer joint part). If there are deviations from sphericity (for example when the relevant surface or its contour is formed by an ellipse or has a free-form curve contour or a torus contour), the actual contact point of the force-generating body can also be close to the surface.

[0028] There is a deviation provided in the known joints between the first pitch circle radius of the sliding surface of the journal and the second pitch circle radius of the recess. It has been found that the ACFG value or its course over the deflection angle is different when the joint is used in coasting / cruising operation or in traction operation. However, the deviation can only be adjusted to the best possible compromise value in the joint, so that there is an ACFG value that is equally suitable for both coasting / cruising operation and traction operation.

[0029] The proposed tripod joint with different pitch circle radii at the contact surface now allows adaptation to the coasting operation or cruising operation on the one hand and adaptation to the traction operation on the other hand. That is, the contact surfaces oriented in different peripheral directions have different properties and even different pitch circle radii from one another. Accordingly, the ACFG value of the joint can be designed specifically for the coasting operation or cruising operation by adapting one (for example, the first) pitch circle radius, and the ACFG value can be designed specifically for the traction operation by adapting the other (that is, in this case, the second) pitch circle radius.

[0030] The first pitch circle radius and the second pitch circle radius differ from one another in particular by a factor of at least 1.001, preferably by a factor of at least 1.005, particularly preferably by a factor of at least 1.01.

[0031] In particular, the first pitch circle radius is smaller or larger than the third pitch circle radius.

[0032] In particular, the second pitch circle radius is smaller or larger than the third pitch circle radius.

[0033] In particular, the value of the first pitch circle radius or the second pitch circle radius corresponds to the value of the third pitch circle radius.

[0034] In particular, the third pitch circle radius is larger or smaller than the first pitch circle radius and the second pitch circle radius.

[0035] That is to say, in particular, all relationships between the pitch circle radii are possible, wherein the first pitch circle radius and the second pitch circle radius always have values ​​that are different from one another or of different magnitude.

[0036] In particular, the contact surface is spherical. However, contours of the contact surface that differ from a spherical shape are also possible. For example, the corresponding contact surface can be formed by a plurality of radii of curvature that differ from one another. The radius starting point can (but not necessarily) be arranged on the corresponding journal axis. The contact surface can also be elliptical or toroidal.

[0037] In particular, the inner peripheral surface contacts the surface of the corresponding contact surface at only one point in a cross section which extends transversely to the second axis of rotation.

[0038] The guide rail is designed to be curved, in particular in a cross section extending transversely to the first axis of rotation. The guide rail's direction in the cross section is formed in particular by a radius or by a plurality of radii. The curvature relative to the outer peripheral surface of the rotating body is designed to be concave. The curvature is designed in particular in the manner of a pointed arch (also known as Gothic). The outer peripheral surface contacts the surface of the guide rail, in particular in the cross section, at only one point or at two points or along a line.

[0039] The contact between the corresponding surfaces described above is described only ideally. If, for example, a convexly curved surface contacts a cylindrical surface, then in an ideally viewed situation, contact only exists at one point, wherein in reality, due to the elastic deformation of the corresponding surfaces, linear contact can exist completely.

[0040] In particular, each rotating body includes an inner ring having an inner peripheral surface, an outer ring having an outer peripheral surface, and a plurality of rolling elements between the inner ring and the outer ring.

[0041] In particular, the outer peripheral surface has a shape which is convex relative to the guide rail.

[0042] In particular, the inner peripheral surface is cylindrical.

[0043] In particular, the inner peripheral surface is designed to be concave relative to the contact surface. In this context, “concave” means that the inner peripheral surface has a central region that is set back relative to the contact surface and has an outer region adjacent to the central region that protrudes toward the contact surface.

[0044] The middle region can be cylindrical or convexly curved. The convex curvature in the middle region can extend in particular with a constant or also changing radius into the outer region. The outer region can have a conical course starting from the middle region (curved or cylindrical).

[0045] The concave embodiment of the inner peripheral surface enables the rotating body or the inner ring to be fixed on the journal during the operation of the tripod joint. Thus, the fixing of the inner ring relative to the outer ring is particularly unnecessary.

[0046] Typically, such a fixation is provided, for example, in such a way that the inner ring can only perform a rotation relative to the outer ring. However, such a fixation (typically a fixing ring at the outer ring or at the inner ring) generates friction losses, since only the outer ring performs a rotational movement about the journal axis when the inner joint part is displaced along the first rotational axis.

[0047] The concave embodiment of the inner peripheral surface now serves to fix the inner ring on the corresponding journal, while the outer peripheral surface is guided in the guide or fixed by the guide (for example with respect to the peripheral direction about the first rotation axis and with respect to the radial direction).

[0048] In particular, each contact surface extends over an angular region extending about the respective journal axis and having an angle of less than 180°, in particular less than 150°, preferably less than 130°.

[0049] The inner joint part has in particular a middle cross section which extends transversely to the second axis of rotation and intersects the center of gravity of the inner joint part. In said cross section, the inner joint part has a minimum thickness (i.e. the sum of the first thickness and the second thickness) in the radial direction or along the corresponding journal axis between the central body and the contact surface. Here, the first thickness (which extends from the journal axis to the first surface of the inner joint part arranged adjacent to the first contact surface) is smaller or larger than the second thickness (which extends from the journal axis to the second surface of the inner joint part arranged adjacent to the second contact surface). The difference between the first thickness and the second thickness is at least one percent of the larger thickness, preferably at least five percent.

[0050] In addition, an inner joint part is proposed, which is used for a tripod joint, in particular for the tripod joint described above. In particular, the inner joint part has at least one central body extending along the second rotation axis and three journals extending from the central body in the radial direction, each having a journal axis and arranged distributed in the peripheral direction. Each journal has a contact surface, which is used to contact the rotating body of the tripod joint. The first contact surface is oriented at least in a first peripheral direction, and the second contact surface is oriented at least in a second peripheral direction pointing opposite to the first peripheral direction. The first contact surface has a first pitch circle radius, and the second contact surface has a second pitch circle radius, wherein the first pitch circle radius and the second pitch circle radius have different values ​​from each other.

[0051] The inner joint part or at least the contact surface can be produced by a machining method (for example turning, milling, grinding) or a forming method (for example forging).

[0052] In particular, explanations concerning the tripod joint can be transferred to the inner joint part and vice versa.

[0053] The tripod joint described or the tripod joint with the inner joint part described can be used in particular at the side shaft of a motor vehicle. The side shaft is in particular connected to the drive unit of the motor vehicle, so that the torque of the drive unit can be transmitted to the wheels of the motor vehicle via the tripod joint.

[0054] The use of the indefinite article ("a"), especially in patent claims and the specification reciting them, should be understood as "this" rather than a numeral. The concepts or components introduced accordingly should be understood as follows, that is, there is at least one and, in particular, there can also be a plurality of them.

[0055] It should be noted as a precaution that the numerals used here ("first", "second", ...) serve primarily (only) to distinguish between a plurality of similar objects, variables or processes, i.e., in particular, no mandatory presupposition is given to a correlation and / or sequence of the objects, variables or processes with respect to one another. If such a correlation and / or sequence is necessary, this is explicitly stated here or can be clearly inferred by a person skilled in the art when studying the specifically described design. As long as a component can occur multiple times ("at least one"), the description of one of the components can also apply to all of the components or a portion of a plurality of the components, but this is not mandatory. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] The invention and the technical field are explained in more detail below with reference to the drawings. It should be noted that the invention should not be limited to the embodiments listed. In particular, it should be noted that the drawings and the size relationships shown in particular are only schematic. Among them:

[0057] Figure 1 A side axle of a motor vehicle is shown in traction operation;

[0058] Figure 2 Shows the basis for inertia or cruise operation Figure 1 The lateral axis;

[0059] Figure 3 A known tripod joint is shown in a view along the coaxially arranged rotation axes;

[0060] Figure 4 A tripod connector according to DE 41 30 183 A1 is shown;

[0061] Figure 5 showing a first graph;

[0062] Figure 6 showing a second graph;

[0063] Figure 7 The invention shows a method of having a driven outer joint component according to Figure 3 Three-pin connector;

[0064] Figure 8 A tripod joint with a driven outer joint part is shown in a view along a coaxially arranged rotation axis;

[0065] Fig. 9 The invention shows a method of having a driven inner joint part according to Figure 3 and 7 Three-pin connector;

[0066] Fig.10 The invention shows a method of having a driven inner joint part according to Figure 8 Three-pin connector;

[0067] Fig.11 Show according to Figure 3 , 4 as well as Figures 7 to 10 The outer joint part of the tripod joint;

[0068] Fig.12 A first embodiment variant of the inner joint part is shown in a view along the second axis of rotation;

[0069] Fig.13 A second embodiment variant of the inner joint part is shown in a view along the second axis of rotation;

[0070] Fig.14 A third graph is shown;

[0071] Fig.15 A fourth graph is shown;

[0072] Fig.16 A view along a second axis of rotation shows a portion of an inner joint part in a third embodiment variant;

[0073] Fig.17 A view along the second axis of rotation shows a portion of the inner joint part in a fourth embodiment variant;

[0074] Fig.18 showing the inner joint part in a view along a second axis of rotation;

[0075] Fig.19 The view along the journal axis shows the Fig.18 The inner joint parts;

[0076] Fig. 20 A side view showing Fig.18 and 19 The inner joint parts;

[0077] Fig.21The tripod joint is shown partially in section in a view along the axis of rotation, with a Figures 18 to 20 The inner joint parts;

[0078] Fig. 22 The view along the journal axis shows the Fig.21 The inner joint part of the rotating body;

[0079] Fig.23 The view along the second rotation axis shows partly in section the Fig. 22 The inner joint part of the rotating body;

[0080] Fig.24 A side view is shown in section according to Fig.21 Three-pin connector;

[0081] Fig.25 A third embodiment variant of the inner joint part is shown in a view along the second axis of rotation;

[0082] Fig.26 The view along the second rotation axis shows the Fig.26 Details of the inner joint parts; and

[0083] Fig. 27 A fourth embodiment variant of the inner joint part is shown in detail in a view along the second axis of rotation. DETAILED DESCRIPTION

[0084] Figure 1 The sideshaft 26 of a motor vehicle 27 is shown in traction operation. The sideshaft 26 connects the wheel 30 of the motor vehicle 27 to a drive unit 28 or a gear mechanism 38. The sideshaft 26 comprises a tripod joint 1 towards the drive unit 28 or towards the gear mechanism 38 and a further joint 29 towards the wheel 30. In traction operation, the direction of the introduced torque 31 and the direction of rotation of the sideshaft 26 are in the same direction (see arrow).

[0085] Figure 2 Show according to Figure 1 Sideshaft 26 in coasting or cruise operation. Figure 1 In coasting or cruising operation, the direction of the introduced torque 31 and the direction of rotation of the side shaft 26 are opposite to each other.

[0086] Figure 3 The known tripod joint 1 is shown in a view along coaxially arranged rotation axes 5 , 10 . Figure 4 A tripod connector 1 according to DE 41 30 183 A1 is shown. Figure 3 and 4 They are described together below. Figure 1 and2 implementation plan.

[0087] The tripod joint 1 comprises an outer joint part 2 and an inner joint part 3 and a plurality of rotating bodies 4. The tripod joint 1 is a sliding joint, wherein the inner joint part 3 can slide relative to the outer joint part 2 along a first rotation axis 5. The outer joint part 2 has a receptacle 6 for the inner joint part 3 extending along the first rotation axis 5, and has three guide rails 9 extending along the first rotation axis 5 and arranged evenly distributed in the peripheral directions 7, 8. The inner joint part 3 has a central body 11 extending along a second rotation axis 10, and has three journals 14 extending from the central body 11 in a radial direction 12, each having a journal axis 13 and arranged evenly distributed in the peripheral directions 7, 8.

[0088] A rotating body 4 is arranged on each journal 14, which contacts the journal 14 with its inner peripheral surface 15 and contacts the corresponding guide rail 9 with its outer peripheral surface 16. Each journal 14 has a contact surface 17, 18 for contacting the inner peripheral surface 15, wherein the first contact surface 17 is oriented at least in a first peripheral direction 7 and the second contact surface 18 is oriented at least in a second peripheral direction 8 pointing opposite to the first peripheral direction 7. When the axes of rotation 5, 10 are arranged coaxially relative to each other, the first and second contact surfaces 17, 18 have a first pitch circle radius 19 and the guide rail 9 has a third pitch circle radius 21.

[0089] In order to achieve particularly advantageous guiding properties, an offset 32 ​​is provided between the first pitch circle radius 19 of the contact surfaces 17 , 18 of the journal 14 and the third pitch circle radius 21 of the guide rail 9 .

[0090] Each rotating body 4 includes an inner ring 22 having an inner peripheral surface 15 , an outer ring 23 having an outer peripheral surface 16 , and a plurality of rolling elements 24 between the inner ring 22 and the outer ring 23 .

[0091] In traction operation of the motor vehicle 27, that is, when the motor vehicle 27 is driven by the drive unit 28, the journal 14 is in contact with the rotor 4 with one of the contact surfaces 17, 18, and the rotor 4 is in contact with only one side of the guide rail 9. In coasting operation or in coasting operation (coasting) of the motor vehicle 27, that is, when the drive torque is introduced from the wheel 30 and the drive unit 28 is further engaged (i.e. coasting operation) or disengaged (i.e. coasting operation), the journal 14 is in contact with the rotor 4 with the other of the contact surfaces 18, 17, and the rotor 4 is in contact with only the other side of the guide rail 9.

[0092] Figure 5 A first graph is shown. Figure 6 A second graph is shown. Figure 5 and6 The ACFG value 34 is plotted on the corresponding vertical axis in [Nrms], and the deflection angle 33 of the tripod joint 1 is plotted on the horizontal axis in [degree].

[0093] The ACFG value 34 varies depending on the deflection angle 33 of the tripod joint 1, wherein the course 35 of the value is defined and can be determined depending on the deflection angle 33 for each tripod joint 1. The area of ​​use of the tripod joint 1 is thus limited by the maximum deflection angle 33, at which the ACFG value 34 exceeds a maximum value 36 which is still considered permissible.

[0094] Figure 5 Shows the Figure 3 and 4 The traction operation direction of the tripod joint 1 is 35. Figure 6 The curve 35 for the coasting / cruising mode of the tripod joint 1 is shown. It can be seen that the use range of the tripod joint 1 is limited by the swivel angle 33 which is exceeded during the coasting / cruising mode at the maximum value 36 of the ACFG value 34 which is still considered permissible.

[0095] Figure 7 The invention shows a method of using a driven outer joint part 2 according to Figure 3 The arrow shows the resultant torque 31 acting on the effective radius of the outer joint part 2 .

[0096] Figure 8 A tripod joint 1 is shown in a view along coaxially arranged rotation axes 5, 10, which has a driven outer joint part 2. The tripod joint 1 comprises an outer joint part 2 and an inner joint part 3 as well as a plurality of rotating bodies 4. The tripod joint 1 is a sliding joint, wherein the inner joint part 3 can slide relative to the outer joint part 2 along a first rotation axis 5. The outer joint part 2 has a receptacle 6 for the inner joint part 3 extending along the first rotation axis 5, and has three guide rails 9 extending along the first rotation axis 5 and arranged evenly distributed in the peripheral directions 7, 8. The inner joint part 3 has a central body 11 extending along a second rotation axis 10, and has three journals 14 extending from the central body 11 in a radial direction 12, each with a journal axis 13 and arranged evenly distributed in the peripheral directions 7, 8.

[0097] A rotating body 4 is arranged on each journal 14, which contacts the journal 14 with its inner peripheral surface 15 and contacts the corresponding guide rail 9 with its outer peripheral surface 16. Each journal 14 has a contact surface 17, 18, which is used to contact the inner peripheral surface 15, wherein the first contact surface 17 is oriented at least in the first peripheral direction 7, and the second contact surface 18 is oriented at least in the second peripheral direction 8 pointing opposite to the first peripheral direction 7.

[0098] Each rotating body 4 includes an inner ring 22 having an inner peripheral surface 15 , an outer ring 23 having an outer peripheral surface 16 , and a plurality of rolling elements 24 between the inner ring 22 and the outer ring 23 .

[0099] When the rotation axes 5 , 10 are arranged coaxially relative to each other, the first contact surface 17 has a first pitch circle radius 19 , the second contact surface 18 has a second pitch circle radius 20 , and the guide rail 9 has a third pitch circle radius 21 , wherein at least the first pitch circle radius 19 and the second pitch circle radius 20 have different values ​​from each other.

[0100] The outer peripheral surface 16 of the rotating body 4 can be rotated relative to the inner peripheral surface 15 of the rotating body 4. The inner peripheral surface 15 is formed by an inner ring 22, which contacts the journal 14 or the contact surfaces 17, 18. Rolling bodies 24 are arranged between the inner ring 22 and the outer peripheral surface 16 so that they can rotate relative to each other.

[0101] The twisting of the inner circumferential surface 15 relative to the outer circumferential surface 16 enables the rotating body 4 to roll down along the guide rail 9 , so that the inner joint part 3 can slide relative to the outer joint part 2 along the first axis of rotation 5 .

[0102] When the inner joint part 3 is pivoted, the rotating body 4 is guided further via the guide rail 9 , wherein the journal 14 pivots relative to the rotating body 4 .

[0103] Apart from the relative rotation, the inner circumferential surface 15 and the outer circumferential surface 16 do not perform any further relative movements relative to one another.

[0104] The pitch circle radii 19, 20 of the journal 14 are so-called effective radii. In the case of an elongated tripod joint 1, they are defined, that is, the axes of rotation 5, 10 are arranged coaxially relative to one another. The effective radius defines the lever arm of the object that generates the force when transmitting the torque 31 (see Figure 8 ). That is, the pitch circle radii 19, 20 of the journal 14 are the radii on which, starting from the second rotation axis 10, the midpoints of the spherical segment-shaped contact surfaces 17, 18 of the journal 14 are arranged in the case of an elongated tripod joint 1.

[0105] The proposed tripod joint 1 with different pitch circle radii 19, 20 at the contact surfaces 17, 18 now allows adaptation to the coasting operation or the cruising operation and adaptation to the traction operation. That is, the contact surfaces 17, 18 oriented in different peripheral directions 7, 8 have different properties from one another and even have different pitch circle radii 19, 20 from one another. Accordingly, the ACFG value 34 of the tripod joint 1 can be designed specifically for the coasting operation or the cruising operation by means of the adaptation of the first pitch circle radius 19, and the ACFG value 34 can be designed specifically for the traction operation by means of the adaptation of the second pitch circle radius 20.

[0106] In this case, second pitch circle radius 20 is smaller than third pitch circle radius 21 , and first pitch circle radius 19 is larger than third pitch circle radius 21 .

[0107] Fig. 9 The invention shows a method of having a driven inner joint part 3 according to Figure 3 and 7 Tripod connector 1. Reference Figure 7 The arrows show the resultant torque 31 acting on the effective radius of the outer joint part 2 , ie the third pitch circle radius 21 .

[0108] Fig.10 The invention shows a method of having a driven inner joint part 3 according to Figure 8 Tripod connector 1. Reference Figure 8 The arrows show the resultant torque 31 acting on the effective radius of the outer joint part 2 , ie the third pitch circle radius 21 .

[0109] Fig.11 Show according to Figure 3 , 4 as well as Figures 7 to 10 The outer joint part 2 of the tripod joint 1 has a receptacle 6 for the inner joint part 3 extending along the first rotation axis 5 and three guide rails 9 extending along the first rotation axis 5 and arranged evenly distributed in the peripheral directions 7 , 8 .

[0110] The guide rail 9 is designed to be curved in the cross section shown, which runs transversely to the first axis of rotation 5. The course of the guide rail 9 in the cross section is formed by a plurality of radii. The curvature is designed to be concave relative to the outer peripheral surface 16 of the rotating body 4. The course of the curvature is designed in the manner of a pointed arch (also referred to as Gothic). The outer peripheral surface 16 contacts the surface of the guide rail 9 at two points in the cross section (see also FIG. 1 ). Figures 7 to 10 ).

[0111] The outer joint part 2 has a guide path 9 which is arranged on a third pitch circle radius 21 .

[0112] Fig.12A first embodiment variant of the inner joint part 3 is shown in a view along the second rotation axis 10. Fig.10 and the inner joint part 3 shown here.

[0113] Each journal 14 has a contact surface 17, 18 for contacting the inner peripheral surface 15, wherein the first contact surface 17 is oriented at least in a first peripheral direction 7 and the second contact surface 18 is oriented at least in a second peripheral direction 8 pointing opposite to the first peripheral direction 7. The first contact surface 17 has a first pitch circle radius 19 and the second contact surface 18 has a second pitch circle radius 20, wherein the first pitch circle radius 19 is greater than the second pitch circle radius 20.

[0114] Fig.13 A second embodiment variant of the inner joint part 3 is shown in a view along the second rotation axis 10. Fig.12 implementation plan.

[0115] In contrast to the first embodiment variant, here the first pitch circle radius 19 is smaller than the second pitch circle radius 20 .

[0116] Fig.14 A third graph is shown. Fig.15 A fourth diagram is shown. Figure 5 and 6 implementation plan. Fig.14 and 15 Describe together.

[0117] The ACFG value 34 is plotted on the corresponding vertical axis in [Nrms] and the deflection angle 33 of the tripod joint 1 is plotted on the horizontal axis in [degrees].

[0118] The ACFG value 34 varies depending on the deflection angle 33 of the tripod joint 1, wherein the course 35 of the value is defined and can be determined depending on the deflection angle 33 for each tripod joint 1. The use range of the tripod joint 1 is thus limited by the maximum bending angle 33, at which the ACFG value 34 exceeds a maximum value 36 which is still considered permissible.

[0119] Fig.14 Shows the Figure 8 and Figures 10 to 13 The traction operation direction of the tripod joint 1 is 35. Fig.15 The curve 35 for the coasting / cruise operation of the tripod joint 1 is shown. It can be seen that the use range of the tripod joint 1 is initially limited by very large values ​​of the yaw angle 33, which is exceeded in both operating modes at the still permissible maximum value 36 of the ACFG value 34.

[0120] Fig.16 A portion of the inner joint part 3 according to a third embodiment variant is shown in a view along the second rotation axis 10. In this case, the journal 14 is produced by a machining-type production method. The rotation axis 37 of the journal geometry for the production process can be seen.

[0121] Fig.17 A section of the inner joint part 3 according to a fourth embodiment variant is shown in a view along the second rotation axis 10. In this case, the journal 14 is produced by a forging process.

[0122] Fig.18 The inner joint part 3 is shown in a view along the second rotation axis 10 . Fig.19 The view along the journal axis 13 shows the Fig.18 The inner joint part 3. Fig. 20 A side view showing Fig.18 and 19 The inner joint part 3. Figures 18 to 20 They are described together below. Figure 8 and Figures 10 to 17 implementation plan.

[0123] Each journal 14 has a contact surface 17 , 18 for contacting the inner peripheral surface 15 , wherein the first contact surface 17 is oriented at least in a first peripheral direction 7 and the second contact surface 18 is oriented at least in a second peripheral direction 8 pointing opposite to the first peripheral direction 7 .

[0124] Each contact surface 17 , 18 extends over an angular region 25 extending about the respective journal axis 13 and having an angle of less than 150°.

[0125] The inner joint part 3 has a central cross section 41 which extends transversely to the second axis of rotation 10 and intersects the center of gravity 42 of the inner joint part 3. In the central cross section 41, the inner joint part 3 has a minimum thickness (i.e. the sum of the first thickness 43 and the second thickness 45) along the radial direction 12 or along the respective journal axis 13 between the central body 11 and the contact surfaces 17, 18. In this case, the first thickness 43, which extends from the journal axis 13 to a first surface 44 of the inner joint part 3 arranged adjacent to the first contact surface 17, is smaller than the second thickness 45, which extends from the journal axis 13 to a second surface 46 of the inner joint part 3 arranged adjacent to the second contact surface 18.

[0126] Fig.21 The tripod joint 1 is shown partially in section in a view along the rotation axes 5, 10, and has a Figures 18 to 20 The inner joint part 3. Fig. 22 The view along the journal axis 13 shows the Fig.21The inner joint part 3 of the rotating body 4. Fig.23 The view along the second rotation axis 10 shows partially in section the Fig. 22 The inner joint part 3 of the rotating body 4. Fig.24 A side view is shown in section according to Fig.21 Three-pin connector 1. Figures 21 to 24 They are described together below. Figure 8 and Figures 10 to 20 implementation plan.

[0127] The tripod joint 1 comprises an outer joint part 2 and an inner joint part 3 and a plurality of rotating bodies 4. The tripod joint 1 is a sliding joint, wherein the inner joint part 3 can slide relative to the outer joint part 2 along a first rotation axis 5. The outer joint part 2 has a receptacle 6 for the inner joint part 3 extending along the first rotation axis 5 and three guide rails 9 extending along the first rotation axis 5 and arranged evenly distributed in the peripheral directions 7, 8. The inner joint part 3 has a central body 11 extending along a second rotation axis 10 and three journals 14 extending from the central body 11 in a radial direction 12, each having a journal axis 13 and arranged evenly distributed in the peripheral directions 7, 8.

[0128] A rotating body 4 is arranged on each journal 14, which contacts the journal 14 with its inner peripheral surface 15 and contacts the corresponding guide rail 9 with its outer peripheral surface 16. Figures 18 to 20 The contact surfaces 17 , 18 described serve for contacting the inner peripheral surface 15 , wherein the first contact surface 17 is oriented at least in a first peripheral direction 7 and the second contact surface 18 is oriented at least in a second peripheral direction 8 pointing opposite to the first peripheral direction 7 .

[0129] The outer peripheral surface 16 of the rotating body 4 can be rotated relative to the inner peripheral surface 15 of the rotating body 4. The inner peripheral surface 15 is formed by an inner ring 22, which contacts the journal 14 or the contact surfaces 17, 18. Rolling bodies 24 are arranged between the inner ring 22 and the outer peripheral surface 16 so that they can rotate relative to each other.

[0130] The twisting of the inner circumferential surface 15 relative to the outer circumferential surface 16 enables the rotating body 4 to roll down along the guide rail 9 , so that the inner joint part 3 can slide relative to the outer joint part 2 along the first axis of rotation 5 .

[0131] When the inner joint part 3 is pivoted, the rotating body 4 is guided further by the guide rail 9, wherein the journal 14 pivots relative to the rotating body 4. The pivot angle 33 is Fig.24 , it is shown that the deflection angle occurs here between the first rotational axis 5 and the second rotational axis 10 .

[0132] Apart from the relative rotation, the inner circumferential surface 15 and the outer circumferential surface 16 do not perform any further relative movements relative to one another.

[0133] The proposed tripod joint 1 with different pitch circle radii 19 , 20 at the contact surfaces 17 , 18 now allows, on the one hand, an adaptation to the coasting or cruising mode and on the other hand an adaptation to the towing mode.

[0134] In this case, second pitch circle radius 20 is smaller than third pitch circle radius 21 , and first pitch circle radius 19 is larger than third pitch circle radius 21 .

[0135] Each rotor 4 comprises an inner ring 22 with an inner peripheral surface 15, an outer ring 23 with an outer peripheral surface 16, and a plurality of rolling bodies 24 between the inner ring 22 and the outer ring 23. The outer peripheral surface 16 has a convex shape relative to the guide rail 9. The inner peripheral surface 15 is cylindrical.

[0136] Fig.25 A third embodiment variant of the inner joint part 3 is shown in a view along the second axis of rotation 10 . Fig.26 The view along the second rotation axis 10 shows the Fig.26 Detail of the inner joint part 3. Fig. 27 A detail of a fourth embodiment variant of the inner joint part 3 is shown in a view along the second axis of rotation 10 .

[0137] Unlike the first and second embodiment variants, the inner peripheral surface 15 is concave relative to the contact surfaces 17, 18. In this context, "concave" means that the inner peripheral surface 15 has a middle area 39 set back relative to the contact surfaces 17, 18 and adjacent to the middle area 39 has an outer area 40 protruding toward the contact surfaces 17, 18.

[0138] The middle region 39 is cylindrical in the third and fourth embodiment variants. In the third embodiment variant, the outer region 40 has a curved course (see Fig.26 ) In a fourth embodiment variant, the outer region 40 has at least partially a conical course starting from the cylindrical middle region 39 .

[0139] The concave embodiment of the inner peripheral surface 15 enables the rotor 4 or the inner ring 22 to be fixed on the journal 14 during operation of the tripod joint 1. As a result, fixing of the inner ring 22 relative to the outer ring 23 is not necessary.

[0140] Typically, such a fixation is provided, for example, in such a way that the inner ring 22 can only perform a rotation relative to the outer ring 23. However, such a fixation (typically a fixing ring on the outer ring 23 or the inner ring 22) generates friction losses, since only the outer ring 23 performs a rotational movement about the journal axis 13 when the inner joint part 3 is displaced along the first rotational axis 5.

[0141] The concave embodiment of the inner peripheral surface 15 now serves to fix the inner ring 22 on the corresponding journal 14 , while the outer peripheral surface 16 is guided in the guide rail 9 or fixed by the guide rail 9 (for example with respect to the peripheral directions 7 , 8 about the first rotation axis 5 and with respect to the radial direction 12 ).

[0142] Reference numerals list

[0143] 1 Tripod connector

[0144] 2 External connector parts

[0145] 3 Inner joint parts

[0146] 4 Rotating body

[0147] 5 First axis of rotation

[0148] 6. Accommodation

[0149] 7 First peripheral direction

[0150] 8 Second peripheral direction

[0151] 9 Guide Rail

[0152] 10 Second axis of rotation

[0153] 11 Centrosome

[0154] 12 Radial direction

[0155] 13 Journal axis

[0156] 14 Journal

[0157] 15 Inner peripheral surface

[0158] 16 Outer peripheral surface

[0159] 17 First contact surface

[0160] 18 Second contact surface

[0161] 19 Radius of the first pitch circle

[0162] 20 Radius of the second pitch circle

[0163] 21 Radius of the third pitch circle

[0164] 22 Inner ring

[0165] 23 External ring

[0166] 24 Rolling elements

[0167] 25 angular area

[0168] 26 Side shaft

[0169] 27 Motor Vehicles

[0170] 28 Drivers

[0171] 29 Connectors

[0172] 30 rounds

[0173] 31 Torque

[0174] 32 Deviation

[0175] 33 Deflection Angle

[0176] 34ACFG value

[0177] 35 Direction

[0178] 36 Highest value

[0179] 37 Rotation axis

[0180] 38 Transmission mechanism

[0181] 39 Middle Area

[0182] 40 External Area

[0183] 41 Middle cross section

[0184] 42 Center of Gravity

[0185] 43 First Thickness

[0186] 44 First Surface

[0187] 45 Second Thickness

[0188] 46 Second surface.

Claims

1. A tripod joint (1), comprising at least an outer joint part (2), an inner joint part (3) and a plurality of rotating bodies (4); wherein: The outer joint part (2) has a receiving portion (6) for the inner joint part (3) extending along a first rotation axis (5) and three guide rails (9) extending along the first rotation axis (5) and arranged distributed in the peripheral direction (7, 8), wherein the inner joint part (3) has a central body (11) extending along a second rotation axis (10) and three journals (14) extending from the central body (11) in a radial direction (12), each having a journal axis (13) and arranged distributed in the peripheral direction (7, 8); wherein one of the rotating bodies (4) is arranged on each journal (14), the rotating body being in contact with the journal (14) with an inner peripheral surface (15) and in contact with the journal (14) with an outer peripheral surface (16) Contact with a corresponding guide rail (9), wherein each journal (14) has a contact surface (17, 18) for contacting the inner peripheral surface (15), wherein the first contact surface (17) is oriented at least in a first peripheral direction (7), and the second contact surface (18) is oriented at least in a second peripheral direction (8) pointing opposite to the first peripheral direction (7); wherein, when the rotation axes (5, 10) are arranged coaxially relative to each other, the first contact surface (17) has a first pitch circle radius (19), the second contact surface (18) has a second pitch circle radius (20), and the guide rail (9) has a third pitch circle radius (21), wherein at least the first pitch circle radius (19) and the second pitch circle radius (20) have different values ​​from each other.

2. The tripod joint (1) according to claim 1, wherein: The first pitch circle radius (19) is smaller than or larger than the third pitch circle radius (21).

3. A tripod joint (1) according to any one of the preceding patent claims, wherein: The second pitch circle radius (20) is greater than or less than the third pitch circle radius (21).

4. A tripod joint (1) according to any one of the preceding patent claims, wherein: The value of the first pitch circle radius (19) or the second pitch circle radius (20) corresponds to the value of the third pitch circle radius (21).

5. The tripod joint (1) according to claim 1, wherein: The third pitch circle radius (21) is larger than or smaller than the first pitch circle radius (19) and the second pitch circle radius (20).

6. A tripod joint (1) according to any one of the preceding patent claims, wherein: Each rotating body (4) comprises an inner ring (22) having the inner peripheral surface (15), an outer ring (23) having the outer peripheral surface (16), and a plurality of rolling bodies (24) between the inner ring (22) and the outer ring (23).

7. A tripod joint (1) according to any one of the preceding patent claims, wherein: The outer peripheral surface (16) has a convex shape relative to the guide rail (9).

8. A tripod joint (1) according to any one of the preceding patent claims, wherein: The inner peripheral surface (15) is cylindrical.

9. The tripod joint (1) according to any one of claims 1 to 7, wherein: The inner peripheral surface (15) is designed to be concave relative to the contact surfaces (17, 18).

10. A tripod joint (1) according to any one of the preceding patent claims, wherein: Each contact surface (17, 18) extends over an angular region (25) extending about the respective journal axis (13) and having an angle of less than 180 degrees.

11. An inner joint part (3) for a tripod joint (1), comprising at least a central body (11) extending along a second axis of rotation (10) and three journals (14) extending from the central body (11) in a radial direction (12), each having a journal axis (13) and arranged distributed along the circumferential direction (7, 8), wherein: Each journal (14) has a contact surface (17, 18) for contacting a rotating body (4) of the tripod joint (1) which can be arranged on each journal (14), wherein the first contact surface (17) is oriented at least in a first peripheral direction (7) and the second contact surface (18) is oriented at least in a second peripheral direction (8) pointing opposite to the first peripheral direction (7); wherein the first contact surface (17) has a first pitch circle radius (19) and the second contact surface (18) has a second pitch circle radius (20), wherein the first pitch circle radius (19) and the second pitch circle radius (20) have different values ​​from each other.

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