Clamping device for a steering column and steering column for a motor vehicle

Abstract

The present invention relates to a clamping device (4) for a steering column (1) of a motor vehicle, comprising a clamping bolt (41) extending axially in the direction of a clamping axis (S) and a clamping lever (5) which is rotationally connected to the clamping bolt (41) via a coupling element (7) and a connecting element (8), wherein the coupling element (7) has an axially projecting first projection (71) and an axially projecting second projection (72) radially opposite the first projection with respect to the clamping axis (41), and the connecting element (8) has a first opening (81) into which the first projection (71) engages axially, and a second opening (82) into which the second projection (72) engages axially, and which is designed to be open radially outwards.In order to enable a more compact design and improved manufacturing, the invention proposes that the second projection (72) has a radial second projection width (V2) which is greater than a radial first opening width (O1) of the first opening (81) and which is greater than a radial second opening width (O2) of the second opening (82).

Description

State of the art

[0001] The invention relates to a clamping device for a steering column of a motor vehicle, comprising a clamping bolt extending axially in the direction of a clamping axis and a clamping lever which is rotationally connected to the clamping bolt via a coupling element and a connecting element, wherein the coupling element has an axially projecting first projection and an axially projecting second projection radially opposite the first projection with respect to the clamping axis, and the connecting element has a first opening into which the first projection axially engages, and a second opening into which the second projection axially engages, and which is open radially outwards. A steering column according to the preamble of patent claim 11 with such a clamping device is also the subject of the invention.

[0002] In the case of an adjustable steering column, in order to adapt the steering wheel position of the steering wheel attached to the rear end of the steering spindle with respect to the direction of travel to the driver's position, it is known to adjust the actuating unit in which the steering spindle is mounted relative to the body-mounted support unit.

[0003] By means of a generic clamping device, which can be moved into either a fixed position (clamping position) or a released position, the actuating unit can be releasably clamped relative to the support unit. In the fixed position, the actuating unit is fixed relative to the support unit during normal driving operation, and in the released position, the actuating unit can be adjusted relative to the support unit to adjust the steering wheel position. To switch between the released and fixed positions, a clamping bolt of the clamping device, which interacts with a lifting device, can be rotated about its axis by actuating a clamping lever connected to it in a rotationally locked manner. Operation can preferably be carried out manually.

[0004] For the rotationally locked connection of the clamping lever to the clamping bolt, EP 3 272 623 B1 discloses coupling a connecting element to a coupling element. The connecting element can be connected to the clamping lever, and the coupling element to the clamping bolt, or vice versa. These two alternatives are included below, even if only the attachment of the connecting element to the clamping lever is mentioned.

[0005] To create the rotationally locked connection, the coupling element has an axially protruding first projection and a second projection located radially opposite the first projection with respect to the axis and parallel to the first projection, also axially protruding. The two projections are arranged in a cam-like manner on the end face facing the connecting element of the clamping lever. On its end face facing the coupling element, the connecting element has a first axial opening into which the first projection engages to form a positive connection effective in the circumferential direction, and a second axial opening into which the second projection engages to form a positive connection effective in the circumferential direction.

[0006] In order to enable compensation of tolerances between the two projections and the associated openings, the aforementioned EP 3 272 623 B1 proposes that the second opening have a second opening width, measured in the radial direction, which is greater than a second projection width of the second projection, also measured in the radial direction. This makes it possible to ensure secure, positive engagement of both projections through relatively simple assembly. However, it is considered disadvantageous that the realization of the increased opening width requires a relatively large dimension of the connecting element. Furthermore, the manufacturing effort is increased by the fact that the connecting element can be positively connected to the coupling element in two assembly positions rotated by 180°, so that complex monitoring of correct assembly is necessary.

[0007] In view of this, it is an object of the present invention to enable a more compact design and improved manufacturing. Description of the invention

[0008] This object is achieved according to the invention by the clamping device having the features of claim 1 and the steering column equipped therewith according to claim 11. Advantageous further developments emerge from the subclaims.

[0009] In a clamping device for a steering column of a motor vehicle, comprising a clamping bolt extending axially in the direction of a clamping axis and a clamping lever which is rotationally connected to the clamping bolt via a coupling element and a connecting element, wherein the coupling element has an axially projecting first projection and an axially projecting second projection radially opposite said first projection with respect to the clamping axis, and the connecting element has a first opening into which the first projection axially engages, and a second opening into which the second projection axially engages, and which is open radially outwards, it is provided according to the invention that the second projection has a radial second projection width which is greater than a radial first opening width of the first opening, and which is greater than a radial second opening width of the second opening.

[0010] The radial second projection width refers to the radial dimension of the second projection, or in other words the dimension of the cross-section of the second projection measured in the radial direction with respect to the axis.

[0011] The first opening is designed to be closed, i.e., it has an opening cross-section defined around its entire circumference by a continuous, closed inner wall. The radial first opening width refers to the radial dimension of the opening cross-section of the first opening, measured in the radial direction.

[0012] The second opening opens radially outwards, i.e. its opening cross-section is closed by its inner wall only radially inwards and in the circumferential direction with respect to the axis. In other words, the second opening is designed as a cutout or recess which is made radially from the outside into the outer circumference of the connecting element. The radial second opening width refers to the radial dimension of the opening cross-section of the second opening. This is measured in the radial direction from the radially inner inner wall of the opening to the circumferential outer edges of the radially outwardly open opening cross-section. The edges refer to the transition between the radially inwardly and circumferentially closed inner wall of the second opening and the outer circumference of the connecting element.In other words, the radial second opening width corresponds to the depth, measured radially inward, of the second opening introduced from the outside as a recess or cutout into the outer circumference of the connecting element. Accordingly, this depth or the radial second opening width extends radially in the same direction as the radial second projection width.

[0013] The second opening can preferably be formed as a recess or cutout introduced radially from the outside into the connecting element, for example a substantially U-shaped cutout or recess.

[0014] An advantage of the invention is that the second projection always projects radially outwards beyond the open circumferential section of the second opening beyond the outer circumference of the connecting element. The greater radial width of the projection relative to the depth of the opening ensures secure engagement to create the positive locking effective in the circumferential direction. Correct assembly can be easily and reliably detected and monitored from the outside by the second projection protruding radially outwards from the second opening. This applies in particular to automated assembly control, e.g. via image recognition, which depends on clearly recognizable optical patterns and / or silhouettes.

[0015] A further advantage is that the second projection, due to its larger radial dimension, cannot be inserted into the relatively smaller first opening. The first projection can be inserted into the first opening, and the second projection can only be inserted into the second opening. This ensures a clearly defined orientation of the connecting element relative to the coupling element, and thus of the clamping lever relative to the clamping bolt. Accordingly, incorrect assembly is eliminated and production is simplified.

[0016] To apply a manual actuation force, the clamping lever can have a radially protruding handle—depending on the design of the connecting element or the coupling element—which can be pivoted manually about the axis. Alternatively, it is conceivable and possible for the clamping lever to be pivoted about the axis by a motorized drive device.

[0017] It is preferred that the radial second projection width of the second projection be greater than the radial first projection width of the first projection. The radial projection width of the first projection can preferably be adapted to the opening width of the first opening, and the radial projection width of the second projection can be adapted to the second opening. This makes the orientation relative to the axis easily recognizable, simplifying unambiguous assignment during assembly.

[0018] It is advantageous for the second projection to have a radial second projection width that is greater than its circumferential width. The circumferential width of the second projection, also called the second circumferential width for short, refers to the dimension of the cross-section of the second projection measured in the circumferential direction. Due to its relatively larger radial dimension, the second projection has a non-circular cross-section that is elongated in the radial direction. One advantage of this design is that a relatively large radial play can be specified with regard to the simultaneous positive engagement of the two projections in the associated openings, for example to compensate for tolerances or for simplified assembly, and yet secure engagement of the second projection in the outwardly open second opening can still be guaranteed in every case.Furthermore, the radially elongated cross-section is also an advantage with regard to the reliable detection of the position and orientation of the assembled parts through automated assembly control via image recognition.

[0019] It can be provided that the radial second opening width of the second opening is smaller than or equal to its circumferential width. The dimension of the second opening measured in the circumferential direction is equal to or smaller than its depth or radial opening width measured in the radial direction. This makes it possible to reduce the radial dimension of the connecting element on the clamping lever and realize an advantageously compact design.

[0020] It is advantageous for the first projection to have a radial first projection width that is less than or equal to its circumferential width. The circumferential width of the first projection, also referred to as the first circumferential width for short, refers to the dimension of the cross-section of the first projection measured in the circumferential direction. This can preferably correspond to its radial dimension, so that the first projection can preferably have a rotationally symmetrical cross-section, for example, circular or polygonal.

[0021] In the aforementioned embodiment, it is preferred that the radial first opening width of the first opening be less than or equal to its circumferential width. The opening cross-section can preferably be adapted to the cross-section of the first projection, so that the latter can be fitted into the opening with a predetermined clearance. For example, the opening can be adapted to the preferably rotationally symmetrical projection and can be designed, for example, circular or polygonal. This enables a space-saving design, and the tolerance of the positive engagement can be defined by the clearance in the radial and circumferential directions.

[0022] Preferably, the clamping lever may include the connecting element. The first and second openings are formed in the clamping lever and correspond to the first and second projections on the coupling element connected to the clamping axis.

[0023] An advantageous development of the aforementioned embodiment is that the connecting element is formed integrally with the clamping lever. This can be achieved by integrating the openings with a handle element.

[0024] It is advantageous for the clamping lever to comprise a sheet metal part. The sheet metal part can be efficiently manufactured by punching, bending, and / or pressing, including the connecting element, preferably in one piece, preferably from sheet steel.

[0025] In an advantageous development, it can be provided that a lifting device operatively connected to the clamping bolt comprises the coupling element. The lifting device is designed to convert a rotation of the clamping bolt about its axis into an axial clamping stroke and can, for example, comprise a wedge-disk, ball-ramp, or tilt-pin mechanism or the like. Such arrangements comprise a functional part that is non-rotatably connected to the clamping bolt, for example, a wedge-disk, a support flange for tilt pins, or the like. Thus, the coupling element according to the invention can preferably be formed together, preferably in a one-piece design. This allows for an advantageously compact construction.

[0026] The invention further comprises a steering column for a motor vehicle, comprising a support unit, by which an actuating unit is adjustably held, and comprising a clamping device which has a clamping bolt which is rotatable about its clamping axis and which cooperates with a lifting device which is designed for the releasable clamping of the support unit to the actuating unit by rotating the clamping bolt which is rotationally connected to a clamping lever via a coupling element and a connecting element, wherein the invention provides that the clamping device is designed according to one of the previously described embodiments or combinations thereof.

[0027] The lifting device can be designed in a manner known per se to convert a rotation of the clamping bolt about its axis into an axial clamping stroke and can, for example, have a wedge disk, ball ramp or tilt pin mechanism or the like. The clamping stroke can, for example, press the side walls of a support unit against each other and clamp them force-fittingly against the actuating unit. During normal driving, the actuating unit is fixed relative to the support unit because the clamping device is in the fixing or clamping position, thus determining the steering wheel position. To adjust the steering wheel position, the clamping device can be moved to the release position by operating the clamping lever, which removes the clamping and allows the actuating unit to be adjusted to the desired steering wheel position relative to the holding unit. The setting can be fixed again by operating the clamping lever in the opposite direction.

[0028] For height adjustment, the adjusting unit can be pivoted relative to the support unit about a height adjustment axis located horizontally perpendicular to the longitudinal axis. Alternatively, or in combination, longitudinal adjustment can be provided by telescopically adjusting the adjusting unit in the longitudinal direction relative to the support unit. Description of the drawings

[0029] Advantageous embodiments of the invention are explained in more detail below with reference to the drawings. In detail: Fig. 1 a steering column according to the invention in a schematic perspective view, Fig. 2 an enlarged detailed view of the steering column according to Fig. 1, Fig. 3 an enlarged detailed view of the clamping device according to the invention according to Fig. 2, Fig. 4 a partial view of the clamping device according to Fig. 3, Fig. 5 an enlarged axial view of the clamping device according to Fig. 2 to 4. Embodiments of the invention

[0030] In the various figures, identical parts are always provided with the same reference symbols and are therefore usually named or mentioned only once.

[0031] Fig. Figure 1 shows a perspective view—obliquely from the rear left relative to the direction of travel of a motor vehicle (not shown here)—of a steering column 1 having a support unit 2. This comprises fastening means 21 for connection to the body of the motor vehicle (not shown), for example, fastening openings as shown. Two side walls 22 extend downward from the support unit 2, opposite one another with respect to a longitudinal axis L.

[0032] A casing unit 23, which is also referred to as outer casing or guide box, is accommodated between the side walls 22.

[0033] An actuating unit 3 is accommodated in the casing unit 23, which has a steering spindle 32 rotatably mounted about its longitudinal axis L extending in the longitudinal direction. At the rear, driver-side end, relative to the direction of travel, the steering spindle 32 has a fastening section 33 for attaching a steering wheel (not shown).

[0034] The actuating unit 3 is accommodated in the casing unit 23 so as to be longitudinally displaceable in the longitudinal direction, i.e. in the direction of the longitudinal axis L, as is schematically indicated by a double arrow.

[0035] The casing unit 23 is pivotally mounted on the support unit 2 about a pivot axis 24 located transversely to the longitudinal axis L. Thus, together with the adjusting unit 3 for adjusting the height position of the steering wheel between the side walls 22, it can be moved up and down relative to the support unit 2 in the height direction H by pivoting it about the pivot axis 24, as indicated by a double arrow.

[0036] A clamping device 4 according to the invention is designed to be selectively moved into a fixing position (clamping position) or a release position (release position). In the fixing position, the casing unit 23 is clamped between the side cheeks 22 and fixed to the support unit 2, and the adjusting unit 3 is clamped in the casing unit 23 by the clamping applied via the side cheeks 22, and is thereby fixed in the longitudinal direction. In the release position, the casing unit 23 can be adjusted in the vertical direction H relative to the support unit 2, and the adjusting unit 3 can be adjusted relative to the casing unit 23 and thus also relative to the support unit 2 in the longitudinal direction.

[0037] The clamping device 4 has a clamping bolt 41 which extends along a clamping axis S lying transversely to the longitudinal axis L through vertically extended elongated holes 25 in both side walls 22 and through openings of the casing unit 23. In Fig. 2, the steering column 1 is shown in an enlarged section in the area of ​​the clamping device 4 without the adjusting unit 3 and the casing unit 23, and in Fig. 3 the clamping device is shown in a separate view.

[0038] A clamping lever 5 is connected to the clamping bolt 41 at one end in a rotationally fixed manner. A lifting device 6 is arranged between the clamping lever 5 and the side wall 22 facing it. The clamping bolt 41 is supported on the other side wall 22 from the outside with respect to the longitudinal axis L via an abutment 42, for example, a screwed-on nut.

[0039] In the example, the clamping device 4 is designed as a cam-link disc or wedge disc device and has a cam disc 70 which is mounted on the clamping bolt 41 in a rotationally fixed manner and which is formed in one piece with the coupling element 7 according to the invention.

[0040] The cam disc 70 of the coupling element 7 interacts with a link disc 61 that is rotatably mounted relative to the clamping bolt 41 and axially supported from the outside against the side cheek 22. The cam disc has cams that project axially against the link disc 61 and that axially bear against a link track that rises axially in sections in the circumferential direction. This forms a lifting mechanism in a conventional manner that, upon rotation of the coupling element 7 with the cam disc, together with the clamping bolt 41, generates a stroke directed axially in the direction of the clamping axis S. By means of this stroke, the two side cheeks 22 can be moved relative to one another in order to releasably clamp the clamping unit 3 to the support unit 2 in the fixing position.

[0041] Alternatively, the clamping device 4 can comprise another mechanism for generating an axial clamping stroke by rotating the clamping bolt 41, for example, a tilting pin or ball ramp arrangement or the like. In this case, a functional element that can rotate together with the clamping bolt is also designed as the coupling element 7.

[0042] The clamping lever 5 has a connecting element 8, which cooperates with the coupling element 7 according to the invention. The function is explained below using the enlarged detailed illustrations in Figs. 3 to 5.

[0043] The coupling element 7 is attached in a rotationally fixed manner to the outer end of the clamping bolt 41 and has an axially projecting first projection 71 and a second projection 72 arranged radially opposite the latter with respect to the clamping axis S. The first projection 71 has a substantially circular or at least rotationally symmetrical cross-section with a radial first projection width V1 measured from the clamping axis S in the radial direction, and a first circumferential width B1 measured in the circumferential direction. Preferably, as in the example shown, V1 is equal to B1. The second projection 72 is elongated in the radial direction with a radial second projection width V2 and a second circumferential width B2 measured in the circumferential direction, wherein preferably, as in the example, V2 > B2 can apply. This is shown in the enlarged view of Fig. 5 recognizable.

[0044] The connecting element 8 has a first opening 81 into which the first projection 71 is axially inserted. The first opening 81 has an opening cross-section adapted to the cross-section of the first projection 71 and a radial first opening width O1. The first opening 81 is closed on all sides, i.e., it encloses the first projection 71 circumferentially over its entire circumference.

[0045] The connecting element 8 has a second opening 82 into which the second projection 72 is axially inserted. The second opening 82 is formed as a substantially U-shaped recess or cutout that is radially introduced from the outside into the outer circumference of the connecting element 8. Accordingly, the second opening 82 is open along its radially outwardly directed circumference. It has a radial second opening width O2. This is measured in the radial direction from the radially inward inner wall of the opening to the circumferential outer edges 83 of the radially outwardly open opening cross-section. The edges 83 denote the transition between the radially inwardly and circumferentially closed inner wall of the second opening 82 and the outer circumference of the connecting element 8.In other words, the radial second opening width O2 corresponds to the depth, measured in the radially inward direction, of the second opening 82 introduced from the outside as a recess or cutout into the outer circumference of the connecting element 8. Accordingly, this depth or the radial second opening width O2 extends radially in the same direction as the second projection width V2.

[0046] The circumferential width of the second opening 82 measured in the circumferential direction is adapted to the second circumferential width B2 of the second projection 72, so that a relatively small play is formed in the circumferential direction, which can preferably correspond approximately to the play in the circumferential direction between the first projection 71 and the first opening 81.

[0047] According to the invention, the radial second projection width V2 of the second projection 72 is larger than the radial first opening width O1 of the first opening 81, and also larger than the radial second opening width O2 of the second opening 82. List of reference symbols 1 steering column 2 carrying unit 21 Fasteners 22 side panels 23 Jacket unit 24 swivel axis 25 slot 3 Actuator 32 steering spindle 33 Fastening section 4 clamping device 41 clamping bolts 42 abutments 5 clamping levers 6 Lifting device 61 Link disc 7 Coupling element 70 cam disc 71 first lead 72 second lead 8 Connecting element 81 first opening 82 second opening 83 Rand L Longitudinal axis H Altitude direction S clamping axis V1 radial first projection width V2 radial second projection width B1 first circumference width B2 second circumference width O1 radial first opening width O2 radial second opening width

Claims

[1] A clamping device (4) for a steering column (1) of a motor vehicle, comprising a clamping bolt (41) extending axially in the direction of a clamping axis (S) and a clamping lever (5) which is rotationally connected to the clamping bolt (41) via a coupling element (7) and a connecting element (8), wherein the coupling element (7) has an axially projecting first projection (71) and an axially projecting second projection (72) radially opposite the first projection (71) with respect to the clamping axis (41), and the connecting element (8) has a first opening (81) into which the first projection (71) engages axially, and a second opening (82) into which the second projection (72) engages axially, and which is open radially outwards, characterized bythat the second projection (72) has a radial second projection width (V2) which is greater than a radial first opening width (O1) of the first opening (81), and which is greater than a radial second opening width (O2) of the second opening (82). [2] Clamping device according to claim 1, characterized by that the radial second projection width (V2) of the second projection (72) is greater than a radial first projection width (V1) of the first projection (71). [3] Clamping device according to one of the preceding claims, characterized by that the second projection (72) has a radial second projection width (V2) which is greater than its circumferential width (B2). [4] Clamping device according to one of the preceding claims, characterized by that the radial second opening width (O2) of the second opening (82) is less than or equal to its circumferential width (B2). [5] Clamping device according to one of the preceding claims, characterized bythat the first projection (71) has a radial first projection width (V1) which is less than or equal to its circumferential width (B1). [6] Clamping device according to one of the preceding claims, characterized by that the radial first opening width (O1) of the first opening (81) is less than or equal to its circumferential width (B1). [7] Clamping device according to one of the preceding claims, characterized by that the clamping lever (5) has the connecting element (8). [8] Clamping device according to claim 7, characterized by that the connecting element (8) is formed integrally with the clamping lever (5). [9] Clamping device according to one of the preceding claims 7 or 8, characterized by that the clamping lever (5) has a sheet metal part. [10] Clamping device according to one of the preceding claims, characterized by that a lifting device (6) operatively connected to the clamping bolt (41) has the coupling element (7). [11] Steering column (1) for a motor vehicle, comprising a support unit (2) by which an actuating unit (3) is adjustably held, and comprising a clamping device (4) which has a clamping bolt (41) which is rotatable about its clamping axis (S) and which cooperates with a lifting device which is designed for the releasable clamping of the support unit (2) to the actuating unit (3) by rotating the clamping bolt (41), which is connected in a rotationally locked manner to a clamping lever (5) via a coupling element (7) and a connecting element (8), characterized by that the clamping device (4) is designed according to one of claims 1 to 10.

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