Adjustable steering column for a motor vehicle

Abstract

The invention relates to an adjustable steering column (1) for a motor vehicle, comprising: a steering column body (10) for supporting a rotatable steering shaft (12), a sleeve (14) arranged longitudinally movably in an opening (10a) of the steering column body (10), a collision tube (16) arranged longitudinally movably in the opening (14a) of the sleeve (14), a plurality of first guide components (18, 20) for guiding the sleeve (14) in the steering column body (10) so that the sleeve (14) moves in the axial direction of the steering column body (10), a plurality of second guide components (30, 32) for guiding the collision tube (16) in the sleeve (14) so ​​that the collision tube (16) moves in the axial direction of the steering column body (10), a drive (56) for adjusting the steering column (1), and a transmission mechanism (48) configured to convert an axial movement of the sleeve (14) into an axial movement of the collision tube (16).

Description

Technical Field

[0001] The invention relates to an adjustable steering column for a motor vehicle. Background Art

[0002] Usually, the steering column in a passenger car can be adjusted in height and length manually or electrically. In particular, longitudinal adjustment is often implemented as a telescopic device between a housing and a telescopic tube (often referred to as a crash tube or guide tube) that implements a pivoting movement for height adjustment.

[0003] Furthermore, some steering columns have a so-called easy entry function, which enables the steering column body of the steering column to be retracted to a depth permitted by the adjustment range of the steering column, which typically has a travel of 25 mm to 35 mm.

[0004] DE 10 2008 060 225 B4 discloses an adjustable steering column for a motor vehicle, comprising a steering column body for supporting a rotatable steering shaft, a clamping device for achieving stepless adjustability of the steering shaft along the longitudinal direction of the steering column body, and an energy absorption device for energy-absorbing displacement of the steering shaft in an accident.

[0005] However, within the scope of autonomous driving of the vehicle, it is desirable to allow a greater adjustment range of the steering column so that the steering column and the steering device mounted thereon can be sunk to the greatest extent possible into the dashboard or interior lining of the vehicle during autonomous driving of the vehicle.

[0006] Conventional steering columns are usually adjusted via a spindle drive coupled to an electric motor, wherein a spindle nut of the spindle drive is coupled to an energy absorption element which in turn has a direct connection to the crash tube.

[0007] It is therefore an object of the present invention to provide an improved adjustable steering column for a motor vehicle which allows a wider adjustability of the telescopic mechanism relative to the steering column body.

[0008] This object is achieved by an adjustable steering column for a motor vehicle according to the invention. Summary of the invention

[0009] The invention provides an adjustable steering column for a motor vehicle, which comprises a steering column body for supporting a rotatable steering shaft, a sleeve arranged in an opening of the steering column body in a longitudinally movable manner, and a crash tube arranged in the opening of the sleeve in a longitudinally movable manner.

[0010] The adjustable steering column further comprises a plurality of first guide assemblies guiding the sleeve in the steering column body for moving the sleeve in the axial direction of the steering column body and a plurality of second guide assemblies guiding the collision tube in the sleeve for moving the collision tube in the axial direction of the steering column body.

[0011] The adjustable steering column further comprises a drive for adjusting the steering column and a transmission mechanism which is designed to convert an axial movement of the sleeve into an axial movement of the crash tube.

[0012] The idea of ​​the present invention is to provide a telescopic mechanism consisting of a sleeve and a crash tube by setting a transmission mechanism, wherein the transmission mechanism is configured to convert the axial movement of the sleeve into the axial movement of the crash tube, and the sleeve and the crash tube are coupled via the transmission mechanism. Therefore, the adjustment path of the steering column is advantageously larger.

[0013] Furthermore, the joint adjustment movement of the sleeve and the crash tube increases the adjustment speed, which is advantageous for the intended application within the scope of autonomous driving operation, since the change from manual driving operation to autonomous driving operation and vice versa can be completed more quickly.

[0014] Advantageous embodiments and developments result from the overall content of the disclosure and from the description with reference to the figures.

[0015] According to a preferred improvement, the transmission mechanism is constructed as a rack transmission mechanism, wherein the transmission mechanism has a first rack axially arranged in the opening of the steering column body, a second rack arranged adjacent to the first rack on the outer circumference of the collision tube, and a gear, the gear meshing with the first rack and the second rack.

[0016] By providing a transmission mechanism, a mechanically stable connection can be provided between the steering column body and the crash tube in an advantageous manner, while at the same time the crash tube and the sleeve can be telescopic.

[0017] According to another preferred improvement, the gear has a central half shaft, wherein a first half shaft section protruding on a first side of the gear is supported in a first needle roller bearing accommodated in the sleeve, and wherein a second half shaft section protruding on a second side of the gear is supported in a second needle roller bearing accommodated in the sleeve.

[0018] Since the gear is accommodated in the first and second needle bearings, the gear is supported in the sleeve when the gear moves along the first and second racks. Therefore, during the axial movement of the sleeve caused by the spindle drive, the gear is advantageously placed in motion.

[0019] Therefore, by rolling of the gear on the first rack and the second rack, a torque transmission is achieved from the sleeve via the gear to the crash tube, so that the crash tube also performs an axial movement.

[0020] According to another preferred improvement, the transmission mechanism has a transmission ratio of 2:1, wherein the transmission mechanism is configured to convert axial adjustment of a sleeve of a first length into axial adjustment of a collision tube of a second length, wherein the value of the second length is twice the value of the first length, that is, the adjustment path of the collision tube is twice the adjustment path of the sleeve.

[0021] Advantageously, the transmission ratio is achieved by the rolling of the gearwheel on the teeth of the first and second racks, wherein the resulting axial movement of the crash tube corresponds to a doubled adjustment path of the sleeve.

[0022] According to another preferred improvement, the first rack and the second rack have a constant toothing along their rolling curves. Thus, the transmission can be provided cost-effectively with structurally simple means.

[0023] According to another preferred refinement, the first toothed rack is fixed in an opening of the steering column body by means of first fixing means, in particular screws, and the second toothed rack is fixed, in particular welded, to the outer circumference of the crash tube. Thus, the first toothed rack and the second toothed rack can be easily assembled to the corresponding fixing components of the steering column in an advantageous manner.

[0024] According to a further preferred development, it is provided that the steering column body has an axial recess for accommodating the first gear rack.

[0025] The first toothed rack can therefore be arranged in a space-saving manner in a recess of the steering column body. As a result, the required structural height of the sleeve is advantageously reduced and the overall structural height of the adjustable steering column is therefore necessarily reduced.

[0026] According to another preferred development, the drive has a motor and a spindle transmission connected to the motor, wherein a spindle nut of the spindle transmission has a rigid connection to a belt, in particular a steel belt, fixed to the sleeve, wherein the spindle nut is designed for axial adjustment of the sleeve by a movement along the spindle.

[0027] The spindle nut of the spindle drive, via its connection to the belt, thus advantageously adjusts the sleeve, which in turn is connected to the crash tube via the transmission.

[0028] According to another preferred improvement, the axial adjustment range of the steering column from the first driving position to the second driving position is at least 70 mm, preferably at least 100 mm. The telescopic mechanism of the steering column thus advantageously enables the steering wheel or steering device to be fully lowered in the dashboard or interior lining of the motor vehicle in the second driving position.

[0029] According to another preferred development, the adjustment speed of the steering column, in particular the combination of the sleeve and the crash tube, is between 10 and 100 mm / s, preferably between 40 and 100 mm / s, particularly preferably between 70 and 100 mm / s. Thus, compared to conventional solutions, an increased adjustment speed of the steering column can be advantageously achieved, which is advantageous for the intended use within the autonomous driving operation of the motor vehicle, since this allows a quick change between manual driving operation and autonomous driving operation and vice versa.

[0030] According to another preferred improvement, a plurality of first guide components have a substantially concave section on the inner circumference of the steering column body, a substantially concave section on the outer circumference of the sleeve, and a plurality of balls, which are arranged in a cavity between the substantially concave section on the inner circumference of the steering column body and the substantially concave section on the outer circumference of the sleeve.

[0031] Since a tube-in-tube type telescopic tube mechanism is provided, the telescopic tube mechanism includes a sleeve arranged longitudinally movably in the opening of the steering column body and a collision tube arranged longitudinally movably in the opening of the sleeve, which is supported by corresponding guide assembly balls, so that a compact adjustment mechanism for adjusting the steering column can be advantageously provided.

[0032] According to another preferred improvement, a plurality of second guide components have a substantially concave section on the inner circumference of the sleeve, a substantially concave section on the outer circumference of the collision tube, and a plurality of balls, which are arranged in a cavity between the substantially concave section on the inner circumference of the sleeve and the substantially concave section on the outer circumference of the collision tube.

[0033] In addition to the advantageously compact adjustment mechanism for adjusting the steering column, this arrangement also has the advantage that the adjustment mechanism can be installed in the steering column in a simple manner. In addition, the guide assembly with multiple balls has the advantage of low friction and low noise adjustability of the tube.

[0034] The described embodiments and developments can be combined with one another as desired.

[0035] Further possible configurations, improvements and embodiments of the invention also include combinations of features of the invention described above or below with reference to the exemplary embodiments that are not explicitly mentioned. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings should facilitate a further understanding of the embodiments of the present invention. The accompanying drawings illustrate the embodiments and, together with the description, serve to explain the principles and schemes of the present invention.

[0037] Further embodiments and many of the advantages mentioned are derived with reference to the drawings. The elements shown in the drawings are not necessarily shown to scale with respect to one another. It is shown in the drawings:

[0038] Figure 1 A schematic diagram showing an adjustable steering column for a motor vehicle according to a preferred embodiment of the present invention;

[0039] Figure 2 A cross-sectional view of an adjustable steering column for a motor vehicle according to a preferred embodiment of the present invention is shown;

[0040] Figure 3 shows a longitudinal section through an adjustable steering column for a motor vehicle in a second driving position according to a preferred embodiment of the present invention; and

[0041] Figure 4 A longitudinal section through an adjustable steering column for a motor vehicle according to a preferred embodiment of the present invention is shown in a first driving position.

[0042] In the figures of the drawings, identical reference signs denote identical or functionally identical elements, components or assemblies, unless otherwise indicated. DETAILED DESCRIPTION

[0043] Figure 1 A schematic diagram of an adjustable steering column for a motor vehicle according to a preferred specific embodiment of the present invention is shown.

[0044] An adjustable steering column 1 for a motor vehicle has a steering column body 10 for supporting a rotatable steering shaft 12. The adjustable steering column 1 also has a sleeve 14 which is arranged longitudinally displaceably in an opening 10a of the steering column body 10. The adjustable steering column 1 also has a crash tube 16 which is arranged longitudinally displaceably in an opening 14a of the sleeve 14.

[0045] Furthermore, the steering column has a spindle gear 52 which is connected to the electric motor 50 . A spindle nut 54 of the spindle gear 52 is connected to the sleeve 14 .

[0046] The spindle drive 52 is configured to axially adjust the sleeve 14 by movement of the spindle nut 54. In order to allow axial adjustability of the sleeve 14 by the spindle nut 54, the steering column body 10 has a slot ( Figure 1 The spindle nut 54 can move relative to the steering column body 10 along the long hole in combination with the sleeve 14 (not shown).

[0047] Figure 2 A cross-sectional view of an adjustable steering column for a motor vehicle is shown according to a preferred embodiment of the present invention.

[0048] The adjustable steering column 1 also has a plurality of first guide assemblies 18, 20 for guiding the sleeve 14 in the steering column body 10, and for moving the sleeve 14 in the axial direction of the steering column body 10. In addition, the adjustable steering column 1 has a plurality of second guide assemblies 30, 32 for guiding the impact tube 16 in the sleeve 14, and for moving the impact tube 16 in the axial direction of the steering column body 10.

[0049] The plurality of first guide assemblies 18, 20 have substantially concave sections 22a, 22b on the inner circumference 10b of the steering column body 10, substantially concave sections 24a, 24b on the outer circumference 14b of the sleeve 14, and a plurality of balls 26, 27, which are arranged in cavities 28a, 28b between the substantially concave sections 22a, 22b on the inner circumference 10b of the steering column body 10 and the substantially concave sections 24a, 24b on the outer circumference 14b of the sleeve 14.

[0050] The plurality of second guide assemblies 30, 32 have substantially concave sections 34a, 34b on the inner circumference 14c of the sleeve 14, substantially concave sections 36a, 36b on the outer circumference 16a of the collision tube 16, and a plurality of balls 38, 39, which are arranged in cavities 40a, 40b between the substantially concave sections 34a, 34b on the inner circumference 14c of the sleeve 14 and the substantially concave sections 36a, 36b on the outer circumference 16a of the collision tube 16.

[0051] The transmission 48 is designed as a rack and pinion transmission. Alternatively, the transmission 48 can be designed in another suitable manner, such as, for example, by an axial transmission, such as a spur gear transmission or a planetary gear transmission.

[0052] The transmission mechanism 48 has a first rack 58 axially arranged in the opening 10a of the steering column body 10. In addition, the transmission mechanism 48 has a second rack 60 arranged on the outer circumference 16a of the collision tube 16 adjacent to the first rack 58. In addition, the transmission mechanism 48 has a gear 62 meshing with the first rack 58 and the second rack 60.

[0053] The gear 62 has a central half shaft 64 . A first half shaft section 64 a of the central half shaft 64 , which protrudes on a first side of the gear 62 , is supported in a first needle bearing 66 accommodated in the sleeve 14 .

[0054] A second half-shaft section 64 b of the central half-shaft 64 , which protrudes on the second side of the gearwheel 62 , is supported in a second needle roller bearing 68 which is accommodated in the sleeve 14 .

[0055] The steering column body 10 also has an axial recess 72 for accommodating the first rack 58 .

[0056] The spindle nut 54 of the spindle drive 52 has a rigid connection to a belt 74 which is fixed to the sleeve 14. The belt 74 is preferably designed as a steel belt and forms an energy absorption element.

[0057] The spindle nut 54 is configured to axially adjust the sleeve 14 by movement along the spindle 53 of the spindle drive 52 .

[0058] Figure 3 A longitudinal section through an adjustable steering column for a motor vehicle according to a preferred embodiment of the present invention is shown in a second driving position.

[0059] exist Figure 3 , the steering column 1 is shown in a second driving position P2 . The second driving position P2 is a steering column position for autonomous driving, in which the steering column 1 , ie the sleeve 14 and the crash tube 16 , are completely sunk into the steering column body 10 .

[0060] The first rack 58 and the second rack 60 have a constant toothing along their rolling curves. Alternatively, the first rack 58 and the second rack 60 may have a variable toothing, for example.

[0061] The first rack 58 is fixed in the opening 10a of the steering column body 10 by means of first fixing means 70a, 70b. The first fixing means 70a, 70b are preferably formed by bolts. The second rack 60 is preferably welded to the outer circumference of the collision tube. Alternatively, the second rack 60 can be connected to the collision tube, for example, by other suitable connecting parts, such as shape-fitting connecting parts.

[0062] Figure 4A longitudinal section through an adjustable steering column for a motor vehicle according to a preferred embodiment of the present invention is shown in a first driving position.

[0063] exist Figure 4 1 shows the steering column 1 in the first driving position P1. The first driving position P1 is a steering column position for manual driving, in which the sleeve 14 and the crash tube 16 are completely moved out. Figure 4 The axial adjustment range V of the second driving position P2 shown in FIG. 1 is at least 70 mm, preferably at least 100 mm.

[0064] The transmission mechanism 48 preferably has a transmission ratio of 2:1. In this case, the transmission mechanism is configured to convert the axial adjustment of the sleeve 14 of the first length L1 into the axial adjustment of the crash tube 16 of the second length L2. The value of the second length L2 is twice the value of the first length L1. Alternatively, other suitable transmission ratios can also be set by matching the toothing of, for example, a rack and / or a gear.

[0065] The adjustment speed of the steering column 1 , ie the combination of the sleeve 14 and the crash tube 16 , is 10-100 mm / s, preferably 40-100 mm / s, particularly preferably 70-100 mm / s.

Claims

1. An adjustable steering column (1) for a motor vehicle, the steering column comprising: A steering column body (10) for supporting a rotatable steering shaft (12); a sleeve (14) arranged in the opening (10a) of the steering column body (10) in a longitudinally movable manner; a collision tube (16) arranged in the opening (14a) of the sleeve (14) in a longitudinally movable manner; a plurality of first guide assemblies (18, 20) for guiding the sleeve (14) in the steering column body (10), the plurality of first guide assemblies enabling the sleeve (14) to move in an axial direction of the steering column body (10); a plurality of second guide assemblies (30, 32) for guiding the collision tube (16) in the sleeve (14), the plurality of second guide assemblies enabling the collision tube (16) to move in the axial direction of the steering column body (10); a drive (56) for axially adjusting the steering column (1); and A transmission mechanism (48) is configured to convert the axial movement of the sleeve (14) into the axial movement of the impact tube (16), wherein: The transmission mechanism (48) is constructed as a rack transmission mechanism, wherein the transmission mechanism (48) has a first rack (58) axially arranged in an opening (10a) of the steering column body (10), a second rack (60) arranged adjacent to the first rack (58) on the outer circumference (16a) of the collision tube (16), and a gear (62) meshing with the first rack (58) and the second rack (60).

2. The adjustable steering column according to claim 1, characterized in that The gear (62) has a central half shaft (64), wherein a first half shaft section (64a) protruding on a first side of the gear (62) is supported in a first needle bearing (66) accommodated in the sleeve (14), and wherein a second half shaft section (64b) protruding on a second side of the gear (62) is supported in a second needle bearing (68) accommodated in the sleeve (14).

3. The adjustable steering column according to claim 1, characterized in that The transmission mechanism (48) has a transmission ratio of 2:1, wherein the transmission mechanism (48) is designed to convert an axial adjustment of a sleeve (14) of a first length (L1) into an axial adjustment of a crash tube (16) of a second length (L2), wherein the value of the second length (L2) is twice the value of the first length (L1).

4. An adjustable steering column according to any one of claims 1 to 3, characterized in that The first rack (58) and the second rack (60) have a constant toothing along their rolling curves.

5. The adjustable steering column according to claim 1, characterized in that The first rack (58) is fixed in the opening (10a) of the steering column body (10) by means of first fixing means (70a, 70b), and the second rack (60) is fixed on the outer circumference of the crash tube.

6. The adjustable steering column according to claim 1, characterized in that The first rack (58) is fixed in the opening (10a) of the steering column body (10) by means of bolts, and the second rack (60) is welded to the outer circumference of the collision tube.

7. An adjustable steering column according to claim 5 or 6, characterized in that The steering column body (10) has an axial recess (72) for accommodating the first rack (58).

8. An adjustable steering column according to any one of claims 1 to 3, characterized in that The drive (56) has a motor (50) and a spindle drive (52) connected to the motor (50), wherein a spindle nut (54) of the spindle drive (52) has a rigid connection to a belt (74) fixed to the sleeve (14), wherein the spindle nut (54) is designed to axially adjust the sleeve (14) by movement along the spindle (53).

9. An adjustable steering column according to any one of claims 1 to 3, characterized in that The drive (56) has a motor (50) and a spindle transmission (52) connected to the motor (50), wherein a spindle nut (54) of the spindle transmission (52) has a rigid connection to a steel belt fixed to the sleeve (14), wherein the spindle nut (54) is designed to axially adjust the sleeve (14) by movement along the spindle (53).

10. An adjustable steering column according to any one of claims 1 to 3, characterized in that The axial adjustment range (V) of the steering column (1) from the first driving position (P1) to the second driving position (P2) is at least 70 mm.

11. An adjustable steering column according to any one of claims 1 to 3, characterized in that The axial adjustment range (V) of the steering column (1) from the first driving position (P1) to the second driving position (P2) is at least 100 mm.

12. An adjustable steering column according to any one of claims 1 to 3, characterized in that The adjustment speed of the steering column (1) or the combination of the sleeve (14) and the crash tube (16) is between 10 and 100 mm / s.

13. An adjustable steering column according to any one of claims 1 to 3, characterized in that The adjustment speed of the steering column (1) or the combination of the sleeve (14) and the crash tube (16) is between 40 and 100 mm / s.

14. An adjustable steering column according to any one of claims 1 to 3, characterized in that The adjustment speed of the steering column (1) or the combination of the sleeve (14) and the crash tube (16) is between 70 and 100 mm / s.

15. An adjustable steering column according to any one of claims 1 to 3, characterized in that The plurality of first guide assemblies (18, 20) include a substantially concave section (22a, 22b) on the inner circumference (10b) of the steering column body (10), a substantially concave section (24a, 24b) on the outer circumference (14b) of the sleeve (14), and a plurality of balls (26, 27), the balls being arranged in a cavity (28a, 28b) between the substantially concave section (22a, 22b) on the inner circumference (10b) of the steering column body (10) and the substantially concave section (24a, 24b) on the outer circumference (14b) of the sleeve (14).

16. An adjustable steering column according to any one of claims 1 to 3, characterized in that The plurality of second guide components (30, 32) have a substantially concave section (34a, 34b) on the inner circumference (14c) of the sleeve (14), a substantially concave section (36a, 36b) on the outer circumference (16a) of the collision tube (16), and a plurality of balls (38, 39), the balls being arranged in a cavity (40a, 40b) between the substantially concave section (34a, 34b) on the inner circumference (14c) of the sleeve (14) and the substantially concave section (36a, 36b) on the outer circumference (16a) of the collision tube (16).

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