CN117985094A - Steering column for a motor vehicle - Google Patents

Abstract

The invention relates to a steering column (1) for a motor vehicle, comprising a sleeve (22) in which a steering spindle (3) is rotatably mounted about a longitudinal axis (L) extending in the longitudinal direction and which can be accommodated in a telescopic manner in an outer jacket (21) in the longitudinal direction, wherein a roller guide (6) has at least one roller (61) which is rotatably mounted on the outer jacket (21) about a roller (62) transversely to the longitudinal axis (L) on a radially movable bearing support (63) and which can roll in the longitudinal direction with its outer circumference on the sleeve (22), wherein a pretensioning device (7) cooperates with the bearing support (63) in order to pretension the roller (61) toward the sleeve (22). In order to be able to better match the existing installation space and to optimize the bearing effect, the invention proposes that the roller guide (6) has at least two rollers (61) which are supported on a bearing support (63) and are spaced apart in the circumferential direction and whose rollers (62) are arranged at an angle to one another.

Description

Steering column for a motor vehicle

Technical Field

The invention relates to a steering column for a motor vehicle, comprising a sleeve in which a steering spindle is rotatably supported about a longitudinal axis extending in a longitudinal direction and which can be accommodated in a telescopic manner in an outer jacket in the longitudinal direction, wherein the roller guide has at least one roller which is rotatably supported on the outer jacket about a roller axis transverse to the longitudinal axis on a radially movable bearing support and which can roll in the longitudinal direction with its outer circumference on the sleeve, wherein a pretensioning device cooperates with the bearing support in order to pretension the roller toward the sleeve.

Background

For the input of a manual steering command, a steering wheel or other manual steering handle is mounted on the end of a steering spindle which is located behind the direction of travel and faces the driver and is rotatably supported about its longitudinal axis in the sheath unit. The sheath unit described above comprises a sleeve which is accommodated telescopically in an outer sheath, which may also be referred to as a guide box or a box rocker arm, in a longitudinal direction given by the longitudinal axis. The outer sheath is held to the vehicle body by a carrier unit. By pushing in or pulling out the sleeve relative to the outer sheath, the steering column can be adjusted longitudinally to adjust the position of the steering wheel.

Simple telescopic assemblies comprising an outer sheath and a sleeve as telescopic elements are known, as well as three-or multi-layer telescopic assemblies in which one or more other sleeves or inner sheaths are telescopically received in the sleeve.

In order to smooth the adjustment and to have little play, it is known to provide a linear roller guide between the outer jacket and the sleeve, as described for example in DE 10 2022 201 101 B1. The guide means has a roller which is rotatably supported relative to the outer jacket about a roller axis transverse to the longitudinal axis, the roller being capable of rolling longitudinally on the outside of the sleeve. In order to ensure play-free rolling, the rollers are supported on a bearing support which can be displaced in a radial manner relative to the outer jacket, i.e. can be displaced toward the longitudinal axis. The bearing support is preloaded radially inwards by a pretensioning device, which may for example comprise spring elements or the like supported on the outer jacket. Thereby allowing the rollers to maintain gapless rolling contact with the outside of the sleeve. In a pretensioning plane transverse to the longitudinal axis, the pretensionable rollers can be opposite one or more support rollers in the fixed bearing, which support rollers are supported on the outer jacket.

The above known telescopic assembly allows a smooth, play-free adjustment while having a high degree of rigidity. However, the arrangement of the pretensioning rollers protrudes radially relatively far in one direction. This makes it difficult to adapt to the available installation space. Furthermore, the support effect achievable by a single pretensioning roller is limited.

In view of the above, it is an object of the present invention to be able to adapt to existing construction space in an improved manner and to optimize the supporting effect.

Disclosure of Invention

According to the invention, this problem is solved by a steering column having the features of claim 1. Advantageous developments can also be found in the dependent claims.

In a steering column for a motor vehicle, comprising a sleeve in which a steering spindle is rotatably supported about a longitudinal axis extending in a longitudinal direction and which is telescopically received in an outer jacket, wherein a roller guide has at least one roller which is rotatably supported on the outer jacket about a roller axis transverse to the longitudinal axis on a radially movable bearing bracket and which can roll in the longitudinal direction with its outer circumference on the sleeve, wherein a pretensioning device cooperates with the bearing bracket in order to pretension the rollers against the sleeve, it is provided according to the invention that the roller guide has at least two rollers which are supported on the bearing bracket, which rollers are spaced apart in the circumferential direction and whose rollers are arranged at an angle to one another.

According to the invention, a paired arrangement is achieved with at least two (preferably exactly two) pretensioning rollers, which are arranged in a pretensioning plane transverse to the longitudinal axis. The rollers are arranged on circumferential sections of a circumferential circle coaxial with the longitudinal axis, which sections lie in the pretensioning plane and are spaced apart from each other in the circumferential direction, wherein the individual rollers are oriented tangentially with respect to the circumferential circle and are tangential to the circumferential circle at contact points. Accordingly, the contact points are offset from each other by an angle α >0 ° about the longitudinal axis, and the rollers are arranged at an angle β=180° - α, i.e. β <180 °, to each other.

Preferably, the rollers are arranged at an angle α relative to each other, wherein: 30 ° < α <90 °. Particularly preferably, α may be about 60 °, so that an optimal support of the sleeve within a semicircle is achieved.

In the present invention, instead of one pretensioning roller in the prior art, two pretensioning rollers are arranged offset in the circumferential direction, whereby the radial height can be reduced, so that the available installation space can be better utilized. The transverse forces acting on the sleeve are supported in different angular directions by the at least two offset rollers, whereby the supporting effect and the natural frequency of the steering column are advantageously increased.

It may be provided that at least two bearing supports are provided, each bearing support supporting at least one roller, and that the bearing supports are preferably movable independently of one another relative to the outer jacket. This allows for a reliable rolling contact of the rollers and improved guidance and support of the roller guide.

Preferably, it can be provided that the two bearing supports are arranged at a distance from one another in the circumferential direction. Preferably, the bearing supports are radially movable independently of each other. The bearing support is also said to be floatingly supported. The pretensioning force can thus be applied to the rollers separately, so that an optimal rolling contact of all rollers with the sleeve can be ensured in each operating situation, in particular in the event of large lateral forces.

Preferably, one bearing support extends in the circumferential direction over one circumferential portion section, and particularly preferably, together with two bearing supports arranged next to one another in the circumferential direction, also only extends over one circumferential portion section in total. The circumferential part-section extends in any case over an angular section of less than 180 °.

Advantageously, the bearing support is guided on a guide surface of the outer jacket. Preferably, all bearing supports are guided in such a way, for example, that the bearing supports are allowed to slide along the guide surface with at least one radial movement component of the guide. Thereby, a defined displacement of the one or more bearing brackets described above relative to the sleeve along the guide rail is preset. In this way, a positive guide, for example a sliding guide, can be realized in order to introduce the preload radially into the roller in the direction defined by the guide.

It may be provided that the bearing support is arranged in an opening of the outer jacket. The openings can preferably be designed as outwardly penetrating openings or as radially inwardly open recesses. The openings or recesses may have guide surfaces on which one or more bearing supports can be guided in radial direction. This has the advantage of easy accessibility for mounting the roller guide, wherein the bearing bracket together with the rollers and the pretensioning device can be inserted from the outside into the outer jacket. In the circumferential direction, the opening preferably extends over an angular section of less than 180 °.

Advantageously, at least one spring element is effectively arranged between the outer jacket and the bearing support. The spring element is an integral part of the aforementioned pretensioning device and exerts an elastic pretensioning force on the bearing bracket, by means of which the rollers mounted therein are pretensioned towards the outside of the sleeve.

The bearing support may be mounted on a support element. The support member is coupled to the outer jacket to support the one or more bearing supports radially outwardly. The pretension may be exerted by the support element radially inwards on the bearing bracket, for example by means of a spring element which is effectively interposed between the support element and the bearing bracket or brackets. The support element may for example have a cover plate mounted on the outside of the outer sheath and at least partially covering the aperture, which cover plate is fixed to the outer sheath, preferably on the outside of the outer sheath, for example by a detachable or non-detachable connection. The use of a common support element for the two bearing supports designed and arranged according to the invention simplifies assembly, reduces installation space requirements and achieves a high level of functional and operational safety.

Advantageously, the bearing holders are elastically supported by the pretensioning device relative to one another and/or relative to the common support element. For example, the two bearing supports can be supported on the support element by a common spring element or by two spring elements. It is also possible to arrange a pretensioning device, for example a spring element, between the two bearing brackets and to load them against each other. The bearing support can be preloaded against the sleeve by means of the guide. One advantage of this is that a simple and robust configuration is possible.

It may be provided that the pretensioning device has a spring-loaded wedge assembly. The wedge assembly may be realized by pressing a wedge element with a flat converging wedge surface in the wedge direction between one or more bearing brackets and the outer jacket, for example by a spring element. The bearing support may also have one or more wedge surfaces that are supported directly or indirectly on the outer jacket. By means of the wedge effect, a force transmission and/or a force deflection can be achieved, so that a sufficiently large preload can be reliably applied to the bearing support in the desired preload direction without effort by means of relatively small force-generating elements (e.g. spring elements or the like) acting on the wedge element.

It may be provided that the rollers are arranged on a pre-tensioning plane perpendicular to the longitudinal axis, in which pre-tensioning plane at least one stationary support roller is arranged opposite the rollers with respect to the longitudinal axis. In a pretensioning plane, two pretensioning rollers mounted on the movable bearing support and at least one support roller mounted in a radial fixed bearing are thus distributed over the circumference. The sleeve is pressed against the support roller by a preload force introduced by the roller. Preferably, exactly two support rollers spaced apart in the circumferential direction can be arranged in the circumferential region opposite the pretensioning roller with respect to the longitudinal axis. In this way, a four-roller bearing is achieved in a pretensioning plane, which bearing is advantageous in terms of high rigidity and functional safety.

Preferably, a mirror-symmetrical arrangement of the rollers and the supporting rollers can be achieved with respect to an imaginary radial plane between the rollers. In an advantageous development, it can be provided that the rollers are angularly offset relative to one another about the longitudinal axis, which is different from the relative angular offset of the supporting rollers.

It can be provided that the two rollers are arranged in axially spaced pretension planes. In this way, two longitudinally spaced roller guides are constructed, each of which is designed according to the invention with at least two pre-tensioning rollers. Thus, a guiding device is provided for the sleeve which can absorb bending rigidity of high transverse force. It is particularly advantageous if two pretensioning rollers and two support rollers are provided on each pretensioning plane, so that the sleeve is guided over a total of eight rollers.

It is possible that the rollers are rotatably supported in a plain bearing in a bearing carrier. Each roller is rotatably supported on a shaft, such as a bearing pin, such as a pin or the like, which is received in a bearing bracket. The advantage of a plain bearing is the high stiffness and natural frequency of the bearing assembly.

Alternatively, it is possible for the rollers to be rotatably mounted in the rolling bearing in the bearing carrier. In this case, each roller is rotatably mounted by means of a surrounding, rotatable rolling element (e.g., a needle ring) on a shaft which is accommodated in a bearing support, for example a bearing pin or the like. The rolling bearing has the advantage of small bearing friction, thereby being convenient for adjustment.

It can be provided that the sleeve has a polygonal hollow profile. The sleeve may be designed as a polygonal tube, for example a quadrangular tube, a hexagonal tube, an octagonal tube, a decade tube or a dodecade tube, having a polygonal cross section and at least one polygonal outer contour. The passage cross section of the outer sheath corresponds to its polygonal outer contour, in which the sleeve is telescopically received. The rollers can roll between edges on the preferably flat side surfaces of the polygonal profile, wherein the rolling contact between the rollers and the sleeve is wider than in the case of a circular cross section, which is advantageous in terms of high rigidity and low surface pressure. Another advantage is a clear and well-defined anti-twist arrangement of the sleeve in the outer sheath.

It may also be provided that at least one inner sheath is telescopically received in the above-mentioned sleeve. In this way, a multi-layered telescopic assembly with at least three telescopic elements, namely an outer sheath, a sleeve and at least one inner sheath, may be provided. Other cannulas and/or inner sheaths may be interposed therebetween, if desired. The multi-layered telescoping assembly may allow a greater ratio between the maximum shortening and maximum extension adjustment conditions of the steering column.

Drawings

Advantageous embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

Figure 1 shows in detail a steering column according to the invention in a schematic perspective view,

Figure 2 shows in detail the steering column according to figure 1 described above in another perspective view,

Figure 3 shows in detail the steering column according to figure 1 described above in a top view from above,

Figure 4 shows in detail a section A-A through the steering column according to figure 3 described above,

Figure 5 shows in detail a section B-B through the steering column according to figure 3 described above,

Figure 6 shows in detail an alternative partial view of the roller guide arrangement of the steering column according to figure 1,

Figure 7 shows in detail an alternative partial view of the pretensioning device of the steering column according to figure 1,

Fig. 8 shows in detail a further view of the pretensioning device according to fig. 7.

Detailed Description

In the different figures, identical components are provided with identical reference numerals throughout the various views and are therefore also generally named or referred to only once, respectively.

Fig. 1 and 2 show perspective views of a steering column 1, and fig. 3 shows a top view.

The steering column 1 has a sheath unit 2 that includes an outer sheath 21 and a sleeve 22 telescopically accommodated in the outer sheath 21 in the longitudinal direction of the longitudinal axis L, and an inner sheath 23 also telescopically accommodated in the sleeve 22 in the longitudinal direction, as indicated by double arrows. The sleeve 22 and the inner sheath 23 may also be referred to together as telescoping elements 21, 22, 23.

In the example shown, the sleeve 22 is designed as a polygonal hollow profile, in particular as a 12-sided tube.

The steering spindle 3 is rotatably supported in the sheath unit 2 about a longitudinal axis L. On a rear end section which is located in relation to the direction of travel and which points in the installed position into the driver's position, the steering spindle 3 has a connecting section 31 for connecting a manual steering handle, for example a steering wheel, which is not shown here.

The sheath unit 2, in particular the outer sheath 21, is held by a carrier unit 4, which can be connected to the vehicle body, not shown here.

An electrically actuated drive 5, in this case a linear spindle drive known per se, is engaged in the longitudinal direction between the outer jacket 21 and the inner jacket 23. This comprises a drive unit 51 which is fastened to the outer jacket 23 and has a spindle nut (not explicitly shown here) which can be driven rotationally about its threaded axis by a motor and in which a threaded spindle 52 engages. The threaded spindle 52 is connected with its free end to the inner jacket 23 in a rotationally fixed and longitudinally fixed manner. By rotationally driving the spindle nut, the threaded spindle 52 can be moved forward or backward relative to the drive unit 51, as indicated by the double arrow in fig. 1, depending on the direction of rotation. Thereby, the inner sheath 23 and the sleeve 22 can be retracted or extended telescopically with respect to the outer sheath 21 in order to adjust the position of the steering wheel in the longitudinal direction.

The cross sections A-A and B-B shown in fig. 3 are arranged on two pretensioning planes through the steering column 1 transverse to the longitudinal axis L, as shown in fig. 4 and 5. In the two pretensioning planes A-A and B-B, respectively, roller guides 6 according to the invention are arranged, which are in principle constructed in the same way, so that in the following, components acting in the same way will be given the same reference numerals.

Each roller guide 6 has two pre-tension rollers 61, each rotatably supported in a bearing bracket 63 about a roller 62 transverse to the longitudinal axis L.

In the radially outwardly extending opening 24 of the outer jacket 22, two bearing supports 63 are displaceably guided parallel to the radial direction (i.e. in the direction of the longitudinal axis L) on guide surfaces 25 located in said opening 24. As indicated by the vertically downward arrow in fig. 4 and 5.

Outside each opening 24, in the upper part in fig. 4 and 5, a support plate 26 is firmly connected to the outer jacket 21 as a support element in the sense of the invention, respectively, for example by means of screws as shown in the example.

A pretensioning device 7 is effectively arranged between the bearing bracket 63 and the bottom surface of the support plate 26 radially inwards (downwards in the figure). The function will be described below with reference to the separate schematic diagrams in fig. 7 and 8.

The pretensioning device 7 has an elastic element in the form of a compression spring 71, which, as shown in fig. 7 and 8, is arranged symmetrically to the two wedge elements 72 supported on the bottom surface of the support plate 26 parallel to the support plate 26, i.e. tangentially with respect to the longitudinal axis L, spring-loaded and forced apart, as indicated by the arrows in fig. 7 and 8.

The wedge elements 72 each rest slidingly against a corresponding wedge surface 64 on the bearing support 63 that is inclined opposite to the circumferential direction. The wedge elements 72 are pressed into between the support plate 26 and one of the bearing brackets 63 by the spring force of the compression springs 71. In the process, the guide surface 25 is loaded parallel to the radial direction towards the longitudinal axis L by a wedge-shaped effect, i.e. pressed downwards in the mounted position, as indicated by the downwards arrow in fig. 7 and 8. Thereby, the rollers 61, which are disposed obliquely thereto, are each preloaded radially inward with a preload force F into rolling contact with the outside of the sleeve 22, as indicated by the dashed arrows in fig. 7 and 8.

As shown in fig. 4 and 5, the support roller 65 is supported on the lower side of the outer sheath 21 arranged opposite to the roller 61 about a shaft 66 fixed with respect to the outer sheath 21. The support rollers may also roll longitudinally on the outside of the sleeve 22. By means of the radial pretensioning force exerted by the rollers 61, the sleeve 22 is pretensioned against the support rollers 65 during rolling contact. Thus, as shown in FIG. 4 or FIG. 5, a four roller bearing is implemented on each of the two preload planes A-A or B-B.

By means of the rollers 62 inclined relative to each other according to the invention, the contact points of the rollers 61 on the circumference of the sleeve 22 are offset relative to each other by an angle α about the longitudinal axis L, as schematically shown in fig. 6. Since the roller 61 rolls on both side surfaces of the uniform 12 sides connected on both sides of the intermediate side surface, α=60° in the illustrated example.

Since the four-roller bearing according to the invention is formed in each of the two pretensioning planes A-A and B-B, which are axially spaced in the longitudinal direction, the sleeve 22 is mounted telescopically in an 8-roller guide which is rigid in bending and can be subjected to high loads under the action of transverse forces.

Description of the reference numerals

1. Steering system

2. Sheath unit

21. Outer sheath

22. Casing pipe

23. Inner sheath

24. Perforating the hole

25. Guide surface

26. Supporting plate

3. Steering main shaft

31. Connection section

4. Bearing unit

5. Adjusting drive

6. Roller guide device

61. Roller

62. Roller shaft

63. Bearing support

64. Wedge-shaped surface

65. Support roller

66. Shaft

7. Pretensioning device

71. Compression spring

72. Wedge element

L longitudinal axis

F pretightening force

A-a pretightening plane

B-B pretension plane

Claims (14)

1. Steering column (1) for a motor vehicle, comprising a sleeve (22) in which a steering spindle (31) is rotatably mounted about a longitudinal axis (L) extending in a longitudinal direction and which is telescopically received in an outer jacket (21) in the longitudinal direction, wherein the roller guide (6) has at least one roller (61) which is rotatably mounted on the outer jacket (21) about a roller (62) transverse to the longitudinal axis (L) on a radially movable bearing support (63) and which is rotatable in the longitudinal direction about its periphery on the sleeve (22), wherein a pretensioning device (7) cooperates with the bearing support (63) in order to pretension the roller (61) against the sleeve (22),

It is characterized in that the method comprises the steps of,

The roller guide (6) has at least two rollers (61) which are supported on a bearing support (63) and are spaced apart in the circumferential direction and whose rollers (62) are arranged at an angle to one another.

2. Steering column according to claim 1, characterized in that the two bearing brackets (63) are arranged at a distance from each other in the circumferential direction.

3. Steering column according to any one of the preceding claims, characterized in that the bearing bracket (63) is guided on a guide surface (25) of the outer jacket (21).

4. Steering column according to any one of the preceding claims, characterized in that the bearing bracket (63) is arranged in an opening (24) of the outer jacket (21).

5. Steering column according to any one of the preceding claims, characterized in that at least one spring element (71) is arranged effectively between the outer jacket (21) and the bearing bracket (63).

6. Steering column according to any one of the preceding claims, characterized in that the two bearing brackets (63) are mounted on a common support element (26).

7. Steering column according to any one of the preceding claims, characterized in that the bearing brackets (63) are elastically supported by pretensioning means (7) against each other and/or against a common support element (26).

8. Steering column according to any one of the preceding claims, characterized in that the pretensioning device (7) has a spring-loaded wedge assembly (64, 72).

9. Steering column according to any one of the preceding claims, characterized in that the rollers (61) are arranged in a pretensioning plane (A-A, B-B) perpendicular to the longitudinal axis (L), in which pretensioning plane at least one stationary supporting roller (65) is arranged opposite the rollers (61) with respect to the longitudinal axis (L).

10. Steering column according to any one of the preceding claims, characterized in that two rollers (61) are arranged in axially spaced pretension planes (A-A, B-B).

11. Steering column according to any one of the preceding claims, characterized in that the rollers (61) are rotatably supported in a plain bearing in a bearing bracket (63).

12. Steering column according to any one of the preceding claims, characterized in that the rollers (61) are rotatably supported in rolling bearings in bearing brackets (63).

13. Steering column according to any one of the preceding claims, characterized in that the sleeve (22) has a polygonal hollow profile.

14. Steering column according to any one of the preceding claims, characterized in that at least one inner jacket (23) is telescopically received in the sleeve (22).