Clamping device for steering column and steering column of motor vehicle

Abstract

This invention relates to a clamping device (4) for a steering column (1) of a motor vehicle, comprising a clamping bolt (41) extending axially along a clamping axis (S), and a clamping rod (5) connected to the clamping bolt (41) in a torsionally anti-torsional manner via a coupling element (7) and a connecting element (8), wherein the coupling element (7) has an axially projecting first protrusion (71) and an axially projecting second protrusion (72), the second protrusion being radially opposite to the first protrusion relative to the clamping axis (41), and the connecting element (8) having a first orifice (81) for axial engagement of the first protrusion (71), and a second orifice (82) for axial engagement of the second protrusion (72) and designed to be radially outwardly open. To achieve a more compact structure and a more optimized manufacturing process, this invention proposes that the radial second protrusion width (V2) of the second protrusion (72) is greater than the radial first orifice width (O1) of the first orifice (81), and greater than the radial second orifice width (O2) of the second orifice (82).

Description

Existing technology

[0001] This invention relates to a clamping device for a steering column of a motor vehicle, comprising a clamping bolt extending axially along a clamping axis, and a clamping rod to which the clamping bolt is torsionally connected in a coupling element and a connecting element, wherein the coupling element has an axially projecting first protrusion and an axially projecting second protrusion, the second protrusion being radially opposite to the first protrusion relative to the clamping axis, and the connecting element having a first orifice for axial engagement of the first protrusion and a second orifice for axial engagement of the second protrusion and designed to be radially outwardly open. Furthermore, steering columns having such clamping devices are also the subject of this invention.

[0002] To accommodate the driver's seating position in the case of an adjustable steering column, one known approach is to adjust the position of the servo unit mounted on the steering shaft relative to a support unit fixed to the vehicle body.

[0003] By employing a universal clamping device that can selectively switch to a fixed position (clamped position) or a disengaged position, the servo unit can be detachably wedge-locked relative to the support unit. In normal driving mode, the servo unit is fixed relative to the support unit in the fixed position; in the disengaged position, the servo unit can be adjusted relative to the support unit to set the steering wheel position. To switch between the disengaged and fixed positions, the clamping bolt, which interacts with the reciprocating mechanism in the clamping device, can be rotated about its own axis by operating the clamping rod, which is torsionally connected to the clamping bolt. Preferably, this operation can be performed manually.

[0004] To achieve a torsional connection between the clamping rod and the clamping bolt, EP 3 272 623 B1 discloses a scheme for torsional coupling of a connecting element and a coupling element. The connecting element can be connected to the clamping rod, and the coupling element can be connected to the clamping bolt, or vice versa. These two alternatives will be covered below, although only the connection of the connecting element to the clamping rod will be mentioned.

[0005] To form a torsional connection, the coupling element has an axially projecting first protrusion and a second protrusion, also axially projecting and parallel to the first protrusion, which is radially opposite to the first protrusion relative to the axis. These two protrusions are arranged in a cam-like configuration on the front side facing the clamping rod connecting element. The connecting element has a first axial orifice on its front side facing the coupling element, into which the first protrusion is inserted to form an effective circumferential form-locking engagement; the connecting element also has a second axial orifice, into which the second protrusion engages to form an effective circumferential form-locking engagement.

[0006] To compensate for the tolerances between the two protrusions and their corresponding orifices, EP 3 272 623 B1 proposes that the width of the second orifice, measured radially, is greater than the width of the second protrusion, also measured radially. This allows for reliable form-locking of the two protrusions through relatively simple assembly. However, this approach has drawbacks: achieving the increased orifice width requires a larger connecting element. Furthermore, since the connecting element can form-lock with the coupling element in two assembly positions rotated 180°, manufacturing difficulty is increased, necessitating meticulous monitoring of proper assembly.

[0007] Therefore, the purpose of this invention is to achieve a more compact structure and a more optimized manufacturing process. Summary of the Invention

[0008] According to the present invention, the above-mentioned objective is achieved by a clamping device having the features of claim 1 and a steering column of claim 10 equipped with the clamping device. Preferred improvements are given in the dependent claims.

[0009] A clamping device for a steering column of a motor vehicle includes a clamping bolt extending axially along a clamping axis and a clamping rod connected to the clamping bolt in a torsion-resistant manner via a coupling element and a connecting element. The coupling element has a first axially projecting protrusion and a second axially projecting protrusion radially opposite the first protrusion relative to the clamping axis. The connecting element has a first orifice for axial engagement of the first protrusion and a second orifice for axial engagement of the second protrusion and designed to be radially outwardly open. According to the invention, the radial width of the second protrusion is greater than the radial width of the first orifice and greater than the radial width of the second orifice.

[0010] The term "radial second protrusion width" refers to the radial dimension of the second protrusion, in other words, the dimension of the cross-section of the second protrusion measured radially relative to the axis.

[0011] The first orifice is designed to be closed—meaning its cross-section is defined by a closed annular inner wall along the entire circumference. The term "radial first orifice width" refers to the radial dimension of the first orifice's cross-section measured radially.

[0012] The second orifice opens radially outward—meaning its cross-section closes only radially inward and circumferentially relative to the axis through its inner wall. In other words, the second orifice is in the form of a groove or notch, radially introduced into the outer periphery of the connecting element from the outside. The term "radial second orifice width" refers to the radial dimension of the orifice's cross-section. This cross-sectional dimension is measured radially, starting from the radially inward inner wall of the orifice, up to the circumferential outer edge of the radially outward-opening orifice cross-section. The edge refers to the transition between the radially inward and circumferentially closed inner wall of the second orifice and the outer circumference of the connecting element. In other words, the radial second orifice width corresponds to the depth of the second orifice, introduced into the outer periphery of the connecting element from the outside as a groove or notch, measured radially inward. Accordingly, this depth, or radial second protrusion width, extends radially in the same direction as the radial second orifice width.

[0013] The second opening is preferably in the form of a groove or cut—for example, a basic U-shaped groove or cut—to radially introduce the connecting element from the outside.

[0014] One advantage of this invention is that the second protrusion always extends beyond the open circumferential portion of the second aperture, radially outward beyond the outer circumference of the connecting element. Because the radial width of the protrusion is greater than the depth of the aperture, a reliable engagement that effectively forms a circumferential locking mechanism is ensured. This radially outward protrusion of the second protrusion from the second aperture allows for easy and reliable external detection and monitoring of assembly correctness. This is particularly useful in automated assembly inspections (e.g., via image recognition), as such inspections rely on clearly discernible optical patterns and / or contours.

[0015] Another advantage is that, due to its larger radial dimension, the second protrusion cannot be inserted into the relatively smaller radial opening of the first orifice. The first protrusion can be inserted into the first orifice, while the second protrusion can only be inserted into the second orifice. This clearly defines the positioning direction of the connecting element relative to the coupling element, and consequently determines the positioning direction of the clamping rod relative to the clamping bolt. Correspondingly, this eliminates incorrect assembly and simplifies the manufacturing process.

[0016] To apply manual operating force, the clamping bar—depending on the design of the connecting or coupling elements—may have radially protruding gripping portions for manual oscillation around the axis. Alternatively, the oscillation of the clamping bar around the axis can also be achieved via a motor drive.

[0017] Preferably, the radial width of the second protrusion is greater than the radial width of the first protrusion. The radial width of the first protrusion is preferably adapted to the width of the first orifice, while the second protrusion is adapted to the width of the second orifice accordingly. This makes the axial direction easy to identify and simplifies precise alignment during assembly.

[0018] Advantageously, the radial width of the second protrusion is greater than its circumferential width. The term "circumferential width of the second protrusion," also simply "second circumferential width," refers to the circumferential dimension of the second protrusion's cross-section. Due to its larger radial dimension, the second protrusion has a non-circular cross-section extending radially. One advantage of this configuration is that a larger radial clearance can be specified when both protrusions simultaneously engage with corresponding orifices—for example, to compensate for tolerances or simplify assembly—while still ensuring reliable engagement of the second protrusion in the outwardly open second orifice under various conditions. Furthermore, the elongated radial cross-section is advantageous for reliably identifying the position and alignment of assembled components in automated assembly inspection assisted by image recognition.

[0019] It can be specified that the radial width of the second orifice is less than or equal to its circumferential width. In this case, the circumferential dimension of the second orifice is equal to or less than its radial depth or radial orifice width. This reduces the radial dimensions of the connecting elements on the clamping rod, achieving a more compact structure.

[0020] Advantageously, the radial width of the first protrusion is less than or equal to its circumferential width. The term "circumferential width of the first protrusion," also simply "first circumferential width," refers to the dimension of the cross-section of the first protrusion measured in the circumferential direction. This dimension may preferably correspond to the radial dimension of the protrusion, thus the first protrusion may preferably have a rotationally symmetric cross-section, such as a circular or polygonal cross-section.

[0021] In the above design, preferably, the radial width of the first orifice is less than or equal to its circumferential width. The orifice cross-section is preferably adapted to the cross-section of the first protrusion so that the latter can be inserted into the orifice with a predetermined gap. For example, the orifice may be adapted to a preferably rotationally symmetric protrusion and may be configured as circular or polygonal. This allows for a space-saving structure, and the form-locking tolerance can be defined by the radial and circumferential gaps.

[0022] Preferably, the clamping rod includes the connecting element. In this case, first and second orifices are introduced into the clamping rod, corresponding to first and second protrusions on the coupling element connected to the clamping axis.

[0023] An advantageous improvement to the above design is that the connecting element and the clamping rod are integrally formed. This can be achieved by integrally forming the orifice and the gripping element.

[0024] Advantageously, the clamping rod comprises a sheet metal forming part. This sheet metal forming part can be efficiently manufactured through stamping, bending, and / or pressing processes, including connecting elements, and is preferably integrally formed, and preferably made of steel sheet.

[0025] In an advantageous improvement, the reciprocating device operatively connected to the clamping bolt may include the coupling element. This reciprocating device is designed to convert the rotation of the clamping bolt about its axis into an axial clamping stroke and may include, for example, a wedge, a ball ramp, or a tilting pin mechanism. Such structures have functional components—such as wedges, support flanges for the tilting pin, etc.—that are torsionally connected to the clamping bolt. Therefore, the coupling element according to the invention is preferably integrally formed with this functional component, preferably as a single unit. This allows for an advantageously compact construction.

[0026] Furthermore, the present invention also covers a steering column for a motor vehicle, comprising: a support unit for adjustingly holding a servo unit; and a clamping device including a clamping bolt rotatable about its clamping axis, the clamping bolt interacting with a reciprocating device designed to disengage the support unit from the servo unit by rotating the clamping bolt, wherein the clamping bolt is torsionally connected to a clamping rod via coupling elements and connecting elements. According to the present invention, the clamping device is constructed using any of the above-described designs or combinations thereof.

[0027] The reciprocating mechanism can be designed to convert the rotation of the clamping bolt about its axis into an axial clamping stroke in a known manner, and may include structures such as wedges, ball ramps, or tilting pin mechanisms. Through this clamping stroke, for example, the side plates of the support unit can be pressed together and locked to the servo unit by force locking. In normal driving mode, the servo unit is fixed relative to the support unit because the clamping device is in a fixed or clamped position, thus determining the steering wheel position. To set the steering wheel position, the clamping device can be switched to the disengaged position by operating the clamping lever, thereby releasing the lock and allowing the servo unit to be adjusted relative to the support unit to the desired steering wheel position. The set position can be locked again by reversing the operation of the clamping lever.

[0028] To achieve height adjustment, the servo unit can swing relative to the support unit around a horizontal height adjustment axis perpendicular to the longitudinal axis. Alternatively, or in combination with the above, longitudinal adjustment can be achieved by extending or retracting the servo unit relative to the support unit in the longitudinal direction. Attached Figure Description

[0029] Advantageous embodiments of the present invention will now be described in more detail with reference to the accompanying drawings.

[0030] Figure 1 The steering column according to the invention is shown in a schematic perspective view;

[0031] Figure 2 Showing according to Figure 1 A magnified detail view of the steering column;

[0032] Figure 3 Showing according to Figure 2 Enlarged detail view of the clamping device according to the present invention;

[0033] Figure 4 Showing according to Figure 3 A partial view of the clamping device;

[0034] Figure 5 Showing according to Figures 2 to 4 An enlarged axial view of the clamping device. Embodiments of the present invention

[0035] In all the accompanying drawings, the same parts are always referred to by the same reference numerals.

[0036] Figure 1 The steering column 1, shown in perspective at a left rearward angle relative to the vehicle's direction of travel (not shown), is equipped with a support unit 2. The latter contains fastening devices 21 for connecting to the vehicle body (not shown), such as the mounting holes illustrated. The support unit 2 extends downward along the longitudinal axis L, with two opposing side plates 22.

[0037] The sleeve unit 23, also known as the housing or guide box, is housed between the two side plates 22.

[0038] The servo unit 3 is housed within the sleeve unit 23. The servo unit has a steering spindle 32, which is mounted to be rotatable about its longitudinal axis L, which extends longitudinally. At the rear, driver's side, end relative to the direction of travel, the steering spindle 32 is provided with a fastening section 33 for mounting a steering wheel (not shown).

[0039] The servo unit 3 is housed within the housing unit 23, enabling it to move longitudinally—that is, in the direction of the longitudinal axis L—as indicated by the double-headed arrow.

[0040] The sleeve unit 23 is mounted on the support unit 2 in a manner that allows it to swing about a swing axis 24 perpendicular to the longitudinal axis L. Therefore, by swinging about the swing axis 24, the sleeve unit, together with the servo unit 3, can move up and down relative to the support unit 2 in the height direction H between the two side plates 22 to set the height position of the steering wheel, as shown by the double arrows.

[0041] The clamping device 4 according to the invention is designed to selectively enter a fixed position (clamping position) or a disengaged position (release position). In the fixed position, the sleeve unit 23 is wedged between the two side plates 22 and fixed to the support unit 2, while the servo unit 3 is clamped within the sleeve unit 23 by a clamping force applied via the side plates 22, thereby being fixed longitudinally. In the disengaged position, the sleeve unit 23 can be adjusted in the height direction H relative to the support unit 2, and the servo unit 3 can be adjusted longitudinally relative to the sleeve unit 23 and therefore also relative to the support unit 2.

[0042] The clamping device 4 includes a clamping bolt 41 extending along a clamping axis S perpendicular to the longitudinal axis L, passing through elongated holes 25 extending in the height direction on both side plates 22 and through holes on the sleeve unit 23. Figure 2 In the middle, the steering column 1 is shown in the clamping device 4 area in a selectively enlarged manner, and the servo unit 3 and the sleeve unit 23 are not shown; Figure 3 The clamping device in the released state is shown in a separate view.

[0043] The clamping rod 5 is connected to the clamping bolt 41 at one end in an anti-torsional manner. The reciprocating device 6 is disposed between the clamping rod 5 and the side plate 22 facing the clamping rod. At the other side plate 22, the clamping bolt 41 is supported from the outside in the longitudinal axis L direction by a stop 42 (e.g., a threaded nut).

[0044] In this example, the clamping device 4 takes the form of a cam-type linkage disc device or a wedge-shaped disc device, and includes a cam disc 70 connected to the clamping bolt 41 in an anti-torsional manner, the cam disc being integrally formed with the coupling element 7 according to the invention.

[0045] The cam disk 70 of the coupling element 7 interacts with a linkage disk 61 rotatable relative to the clamping bolt 41, which is axially supported externally against the side plate 22. The cam disk has cams that project axially and abut against the linkage disk 61, these cams partially abutting axially against a linkage track that rises in the circumferential direction and partially extends in the axial direction. Thus, a reciprocating mechanism is formed in a known manner, which generates an axial stroke pointing in the direction of the clamping axis S as the coupling element 7 rotates together with the cam disk and the clamping bolt 41, through which the two side plates 22 can move relative to each other, thereby locking the fastening unit 3 and the support unit 2 in a disengaged manner in a fixed position.

[0046] Alternatively, the clamping device 4 can generate another mechanism for producing axial clamping stroke by rotating the clamping bolt 41—such as a tilting pin or ball ramp arrangement. In this case, the functional element that can rotate with the clamping bolt is also in the form of a coupling element 7.

[0047] The clamping rod 5 includes a connecting element 8, which interacts with the coupling element 7 according to the invention. The following will be combined with... Figures 3 to 5 The enlarged detail diagram shown illustrates its function.

[0048] The coupling element 7 is torsionally connected to the outer end of the clamping bolt 41 and includes an axially projecting first protrusion 71 and a second protrusion 72 arranged radially opposite to the first protrusion relative to the clamping axis S. The first protrusion 71 has a substantially circular or at least rotationally symmetric cross-section, with a radial first protrusion width V1 measured radially along the clamping axis S and a first circumferential width B1 measured circumferentially. As shown in the example, V1 is preferably equal to B1. The second protrusion 72 is radially elongated, with a radial second protrusion width V2 and a second circumferential width B2 measured circumferentially, preferably satisfying V2 > B2, as shown in the example. This is in Figure 5 It can be seen in the magnified view.

[0049] The connecting element 8 has a first orifice 81 into which a first protrusion 71 is axially inserted. The first orifice 81 has an orifice cross-section adapted to the cross-section of the first protrusion 71, and its radial first orifice width is O1. The first orifice 81 is designed to be fully enclosed—that is, it circumferentially surrounds the entire circumference of the first protrusion 71.

[0050] The connecting element 8 has a second orifice 82 into which a second protrusion 72 is axially inserted. The second orifice 82 is in the form of a generally U-shaped groove or cutout, extending radially outward into the outer circumference of the connecting element 8. Accordingly, the second orifice 82 is open in its radially outward circumferential direction. The second orifice has a radial second orifice width O2. This width is measured radially from the radially inner wall of the orifice to the circumferentially outer edge 83 of the radially outwardly open cross-section of the orifice. Edge 83 refers to the transition between the radially inner and circumferentially closed inner wall of the second orifice 82 and the outer circumference of the connecting element 8. In other words, the radial second orifice width O2 corresponds to the depth measured radially inward from the second orifice 82, which is introduced as a groove or cutout into the outer circumference of the connecting element 8 from the outside. Accordingly, this depth, or radial second orifice width O2, extends radially in the same direction as the width V2 of the second protrusion.

[0051] The circumferential width of the second orifice 82, measured in the circumferential direction, is adapted to the second circumferential width B2 of the second protrusion 72, thus forming a relatively small gap in the circumferential direction, which preferably corresponds approximately to the circumferential gap between the first protrusion 71 and the first orifice 81.

[0052] According to the present invention, the radial second protrusion width V2 of the second protrusion 72 is greater than the radial first orifice width O1 of the first orifice 81, and is also greater than the radial second orifice width O2 of the second orifice 82. List of reference numerals 1. Steering column 2 Support Unit 21 Fastening device 22 Side panels 23 Casing Units 24. Swing axis 25 Slender holes 3 Servo Units 32 Steering Axle 33 Fastening Section 4. Clamping device 41 Clamping bolts 42 Stop components 5. Clamping rod 6. Reciprocating device 61 Linkage Panel 7. Coupling element 70 Cam Disc 71 First protrusion 72 Second protrusion 8 Connecting elements 81 First Orifice 82 Second Orifice 83 Edge L longitudinal axis H (height direction) S clamping axis V1 Radial First Protrusion Width V2 Radial second protrusion width B1 First circumferential width B2 Second Circumferential Width O1 Radial first orifice width O2 Radial second orifice width

Claims

1. A clamping device (4) for a steering column (1) of a motor vehicle, comprising a clamping bolt (41) extending axially along a clamping axis (S) and a clamping rod (5) connected to the clamping bolt (41) in a torsion-resistant manner via a coupling element (7) and a connecting element (8). in, The coupling element (7) has an axially protruding first protrusion (71) and an axially protruding second protrusion (72), the second protrusion being radially opposite to the first protrusion relative to the clamping axis (41), and the connecting element (8) having a first orifice (81) for axial engagement of the first protrusion (71) and a second orifice (82) for axial engagement of the second protrusion (72) and designed to be radially outwardly open. Its features are, The radial second protrusion width (V2) of the second protrusion (72) is greater than the radial first orifice width (O1) of the first orifice (81) and greater than the radial second orifice width (O2) of the second orifice (82).

2. The clamping device according to claim 1, characterized in that, The radial second protrusion width (V2) of the second protrusion (72) is greater than the radial first protrusion width (V1) of the first protrusion (71).

3. The clamping device according to any one of the preceding claims, characterized in that, The radial width (V2) of the second protrusion (72) is greater than its circumferential width (B2).

4. The clamping device according to any one of the preceding claims, characterized in that, The radial second orifice width (O2) of the second orifice (82) is less than or equal to its circumferential width (B2).

5. The clamping device according to any one of the preceding claims, characterized in that, The radial width (V1) of the first protrusion (71) is less than or equal to its circumferential width (B1).

6. The clamping device according to any one of the preceding claims, characterized in that, The radial width (O1) of the first orifice (81) is less than or equal to its circumferential width (B1).

7. The clamping device according to any one of the preceding claims, characterized in that, The clamping rod (5) includes the connecting element (8).

8. The clamping device according to claim 7, characterized in that, The connecting element (8) is integrally formed with the clamping rod (5).

9. The clamping device according to any one of claims 7 and 8, characterized in that, The clamping rod (5) comprises a sheet metal forming part.

10. The clamping device according to any one of the preceding claims, characterized in that, The reciprocating device (6) operatively connected to the clamping bolt (41) includes the coupling element (7).

11. A steering column (1) for a motor vehicle, comprising: Support unit (2) is used to hold servo unit (3) in an adjustable manner; And a clamping device (4) comprising a clamping bolt (41) rotatable about its clamping axis (S), the clamping bolt interacting with a reciprocating device designed to disengage the support unit (2) from the servo unit (3) by rotating the clamping bolt (41), wherein the clamping bolt (41) is torsionally connected to the clamping rod (5) via a coupling element (7) and a connecting element (8). Its features are, The clamping device (4) is designed according to any one of claims 1 to 9.

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