GB2624939A

GB2624939A - A connector for a steering column assembly

Info

Publication number: GB2624939A
Application number: GB2219455.9A
Authority: GB
Inventors: Uchyla Damian; Ponikiewski Pawel; Brzoska Marcin; Gola Wojciech
Original assignee: Zf Steering Systems Poland Sp zoo
Current assignee: Zf Steering Systems Poland Sp zoo
Priority date: 2022-12-01
Filing date: 2022-12-21
Publication date: 2024-06-05
Also published as: GB202219455D0

Abstract

A connector 36 is provided for attaching a linear actuator to a steering column (10, Figure 1) of a vehicle. Connector 36 comprises a mount 52 securable to a tube of the steering column, a housing 38 attached to mount 52 and a threaded aperture 64 for receipt of a leadscrew 26 of a linear actuator. The position of aperture 64 is displaceable translationally and/or rotationally with respect to mount 52. Aperture 64 may be provided by a rotatable bushing in housing 38 and a bearing may be provided between the housing and the bushing. Housing 38 may be movable relative to mount 52, for example by a hinge or other pivot or alternatively may be fixed, an interference fit or moveable within a mounting frame, for example with a guide pin and a slot. A steering column and a vehicle are also provided.

Description

A CONNECTOR FOR A STEERING COLUMN ASSEMBLY

This invention relates generally to connectors for steering column assemblies. More specifically, although not exclusively, this invention relates to connectors for attaching actuators, and in particular linear actuators, to steering column assemblies of vehicles, to steering column assemblies comprising such connectors and to vehicles comprising such steering column assemblies.

Adjustable steering column assemblies often comprise a plurality of telescopically mounted io tubular members and an actuator controllable to move the tubular members relative to one another in order to adjust the overall length of the assembly, and therefore the position of a steering wheel attached at one end of the assembly. It has been found that manufacturing imperfections in the tubular members can lead to range of issues in the final assembly if not addressed during manufacture or prior to assembly.

Some of the issues that may arise include excess friction between components or excessive levels of stress between components in the final assembly. This may be the result of the actuator, which is normally a linear actuator, having an adjustment axis that is offset from that of the tubular members. This often results in excessive noise and vibration during adjustment, unpredictable or intermittent motion during adjustment or, in some extreme cases, failure of components of the assembly. Further, excess friction can cause high peak forces required to be overcome in order to adjust the assembly which may either prevent motion or overload the actuator configured to provide the adjustment.

Furthermore, during a vehicle crash event it is important for the steering column to collapse with minimal resistance, such that the steering wheel provides minimal impact to an occupant of the vehicle. Excess friction between tubular members, as a result of manufacturing imperfections, may result in an undesirable response in a crash event.

It has been found that the aforementioned issues may be overcome by providing one or more degrees of freedom to the connection between the actuator and the tubular members of the assembly. This can compensate for the offset of the respective adjustment axes.

In accordance with the present invention, a connector for attaching a linear actuator to a steering column of a vehicle, comprises: a mounting means configured to be secured to a tube of a steering column; a housing attached to the mounting means and comprising a threaded aperture for receipt of a leadscrew of a linear actuator; wherein the position of the aperture is displaceable translationally and/or rotationally with respect to the mounting means.

The connector allows the leadscrew longitudinal axis to displace laterally relative to the adjustment axis of the steering column and to rotate relative to the adjustment axis.

Therefore, if a component (e.g. tube) of the steering column is misaligned, the connector io can compensate for the misalignment by allowing for adjustment of the axis of the leadscrew as the steering column assembly is adjusted. This can reduce frictional forces and reduce stress applied through the leadscrew.

Furthermore, the translation/rotation of the axis of the leadscrew also allows for a more reliable collapse of the steering column assembly in the event of an impact, e.g. during a crash. Misalignment between one or more relatively movable components (e.g. telescopically arranged tubes) forming part of the steering column which may cause excess friction between components, and therefore an unpredictable collapse, can be compensated for by the connector.

Finally, the connector can provide compensation for manufacturing intolerances between one or more relatively movable components (e.g. telescopically arranged tubes) of the steering column, thereby facilitating faster construction/assembly of the steering column assembly.

The connector may comprise a bushing. The bushing may be received within the housing. The bushing may comprise the aperture e.g. for receipt of a lead screw of a linear actuator.

The bushing may be rotatable within the housing e.g. to allow the position of the aperture to be displaced relative to the mounting means.

The bushing may be rotatable about an axis normal to a longitudinal axis of the aperture.

The connector may comprise a bearing. The bearing may be located between the bushing and the housing.

The bearing may be rotationally fixed with respect to the housing or the bushing.

The bearing may comprise two parts located between the bushing and the housing. The bearing may comprise an outer part and an inner part. A first bearing or outer bearing may be rotationally fixed with respect to the housing. A second bearing or inner bearing may be rotationally fixed with respect to the bushing. A first bearing or outer bearing may be rotationally fixed with respect to a second bearing or inner bearing. At least a portion of the first bearing or outer bearing may surround at least a portion of the second bearing or inner bearing.

The bearing may comprise a part-spherical outer surface and/or a part-spherical inner surface.

An outer surface of the first bearing or outer bearing may contact an inner surface of the housing. An inner surface of the first bearing or outer bearing may contact an outer surface of the second bearing or inner bearing. An inner surface of the second bearing or inner bearing may contact an outer surface of the bushing.

The bushing may be displaceable translafionally relative to the mounting means and/or housing e.g. to allow the position of the aperture to be displaced translationally with respect to the mounting means.

The bushing, bearing or first bearing may comprise a protrusion. The protrusion may be received in a recess, aperture or opening e.g. to limit the rotational displacement of the bushing with respect to the housing.

The protrusion may be rotationally fixed with respect to the bushing, bearing or first bearing. The recess, aperture or opening may be provided in the bearing or second bearing. The recess, aperture or opening may be provided in the housing. A, e.g. corresponding, recess, aperture or opening may be provided in each of the housing and the bearing or second bearing.

The recess, aperture or opening may comprise an elongate slot.

The elongate slot may extend substantially parallel with a longitudinal axis of the aperture.

The housing may be movable relative to the mounting means e.g. so as to displace the position of the aperture translationally and/or rotationally relative thereto.

The housing may be pivotably attached to the mounting means.

The housing may be attached to the mounting means via a hinge. The hinge may comprise a first aperture extending through the housing. The hinge may comprise a second aperture extending through the mounting means. The hinge may comprise a pin extending through each of the first aperture and second aperture. The second aperture may have diameter io greater than the first aperture. The axis of the pin may be offset e.g. in order to provide an eccentric mounting.

The mounting means may comprise a mounting frame. The mounting frame may have a pair of longitudinally spaced flanges. The housing may be located between the flanges and is displaceable with respect thereto. The housing may be displaceable relative to the mounting frame.

The housing may comprise a slot. The mounting frame may comprise a guide pin extending between the longitudinally spaced flanges. The guide pin may be received within the slot and may be configured to move radially therealong as the housing is displaced relative to the mounting frame. The slot may be a longitudinally extending slot.

The housing may be fixedly attached to the mounting means.

The housing may be attached to the mounting means in an interference fit.

The housing may define or describe a two-part construction, formed as a pair of connected parts.

The mounting means may comprise a mounting bracket.

The steering column may comprise a plurality of telescopic tubes. The linear actuator may comprise a rotatable leadscrew. The steering column may be adjustable in length along an adjustment axis by operation of the linear actuator.

A further aspect of the invention provides a steering column assembly for a vehicle, comprising: a plurality of telescopic tubes mounted so as to be moveable relative to one another along an adjustment axis; a linear actuator comprising a rotatable leadscrew configured to move the telescopic tubes relative to one another; wherein the steering column is adjustable in length along the adjustment axis by operation of the linear actuator; and a connector attaching the linear actuator to one of the plurality of telescopic tubes, io the connector comprising: a mounting means secured to one of the plurality of telescopic tubes; a housing attached to the mounting means and comprising a threaded aperture, wherein the leadscrew of the linear actuator is received within the threaded aperture; wherein the position of the aperture is displaceable translationally and/or rotationally with the respect to the adjustment axis so as to displace a longitudinal axis of the leadscrew with respect to the adjustment axis.

A further aspect of the invention provides a vehicle comprising a connector as described above or a steering column assembly as described above.

For the avoidance of doubt, any of the features described herein apply equally to any aspect of the invention.

Another aspect of the invention provides a computer program element comprising and/or describing and/or defining a three-dimensional design for use with a simulation means or a three-dimensional additive or subtractive manufacturing means or device, e.g. a three-dimensional printer or CNC machine, the three-dimensional design comprising an embodiment of the connector described above.

For purposes of this disclosure, and notwithstanding the above, it is to be understood that any controller(s), control units and/or control modules described herein may each comprise a control unit or computational device having one or more electronic processors. The controller may comprise a single control unit or electronic controller or alternatively different functions of the control of the system or apparatus may be embodied in, or hosted in, different control units or controllers or control modules. As used herein, the terms "control unit" and "controller" will be understood to include both a single control unit or controller and a plurality of control units or controllers collectively operating to provide the required control functionality. A set of instructions could be provided which, when executed, cause said controller(s) or control unit(s) or control module(s) to implement the control techniques described herein (including the method(s) described herein). The set of instructions may be embedded in one or more electronic processors, or alternatively, may be provided as software to be executed by one or more electronic processor(s). For example, a first controller may be implemented in software run on one or more electronic processors, and one or more other controllers may also be implemented in software run on or more io electronic processors, optionally the same one or more processors as the first controller. It will be appreciated, however, that other arrangements are also useful, and therefore, the present invention is not intended to be limited to any particular arrangement. In any event, the set of instructions described herein may be embedded in a computer-readable storage medium (e.g., a non-transitory storage medium) that may comprise any mechanism for is storing information in a form readable by a machine or electronic processors/computational device, including, without limitation: a magnetic storage medium (e.g., floppy diskette); optical storage medium (e.g., CD-ROM); magneto optical storage medium; read only memory (ROM); random access memory (RAM); erasable programmable memory (e.g., EPROM ad EEPROM); flash memory; or electrical or other types of medium for storing such information/instructions.

Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and/or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and/or features of any embodiment can be combined in any way and/or combination, unless such features are incompatible. For the avoidance of doubt, the terms "may", "and/or', "e.g.", "for example" and any similar term as used herein should be interpreted as non-limiting such that any feature so-described need not be present. Indeed, any combination of optional features is expressly envisaged without departing from the scope of the invention, whether or not these are expressly claimed. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner.

Embodiments of the invention will now be described by way of example only with reference to the accompanying drawings in which: Figure 1 is a perspective view of an embodiment of a steering column assembly in accordance with the present invention; Figure 2 is a perspective view of a first variant of a connector for attaching a linear actuator to a steering column in accordance with the present invention, and which forms part of the steering column assembly of Figure 1; Figure 3 is a front view, partially cut away, of the connector of Figure 2; Figure 4 is a longitudinal sectional view of the connector of Figure 2 taken through vertical plane B-B of Figure 3; Figure 5A is a front view of the connector of Figure 2 with the leadscrew longitudinal axis in a first position; Figure 5B is a front view of the connector of Figure 2 with the leadscrew longitudinal axis in a second position; Figure 6A is a detail view of the connection between the housing and the mounting means of Figure 5A; Figure 6B is a detail view of the connection between the housing and the mounting means of Figure 5B; Figure 7 is a schematic of a steering column assembly showing the position of the leadscrew when the leadscrew longitudinal axis is in the first position of Figure 5A and the second position of Figure 5B; Figure 8A is a plan view of the connector of Figure 2 with the leadscrew longitudinal axis in a first rotational position; Figure 83 is a plan view of the connector of Figure 2 with the leadscrew longitudinal axis in a second rotational position; Figure 9 is a schematic of a steering column assembly showing the position of the leadscrew when the leadscrew longitudinal axis is in the first rotational position of Figure 8A and the second rotational position of Figure 8B; Figure 10 is a perspective view of a second variant of a connector for attaching a linear actuator to a steering column in accordance with the present invention, and io which can form part of the steering column assembly of Figure 1; Figure 11 is a front view, partially cut away, of the connector of Figure 10; Figure 12 is a longitudinal sectional view of the connector of Figure 10 taken through vertical plane C-C of Figure 11; Figure 13 is a front view of the connector of Figure 10; Figure 14 is a sectional view taken through vertical plane D-D of Figure 13; Figure 15 is a detail view of region E of Figure 14; Figure 16A is a front view of the connector of Figure 10 with the leadscrew longitudinal axis in a first position; Figure 16B is a front view of the connector of Figure 10 with the leadscrew longitudinal axis in a second position Figure 17 is a schematic of a steering column assembly showing the position of the leadscrew when the leadscrew longitudinal axis is in the first position of Figure 16A and the second position of Figure 16B; Figure 18A is a plan view showing of the connector of Figure 10 with the leadscrew longitudinal axis in a first rotational position; Figure 18B is a plan view through of the connector of Figure 10 with the leadscrew longitudinal axis in a second rotational position; and Figure 19 is a schematic of a steering column assembly showing the position of the leadscrew when the leadscrew longitudinal axis is in the first rotational position of Figure 18A and the second rotational position of Figure 18B; Figure 1 illustrates a steering column assembly 10 in accordance with present invention, for a vehicle. The steering column assembly 10 is telescopically adjustable along an io adjustment axis A-A which is coincident with the rotational axis of an elongate steering column 12, to the outer end 14 of which a steering wheel (omitted from the drawings for clarity) is attached, in use.

The steering column assembly 10 includes an outermost elongate housing portion ("tube") 16 which slidably and telescopically receives an intermediate elongate housing portion ("tube") 18 which, in turn, slidably and telescopically receives an innermost elongate housing portion ("tube") 20. In use, the outermost elongate tube 16 is secured to a vehicle into which the steering column assembly 10 is to be installed. The elongate steering column 12 is rotatably mounted within the innermost elongate tube 20 and the relative positions of the outermost, intermediate and innermost tubes 16, 18, 20, and therefore the position of the steering wheel attached to the end 14 of the steering column 12, can be adjusted by displacing the tubes with respect to one another along the adjustment axis A-A.

The mechanism 24 for displacing the outermost, intermediate and innermost tubes 16, 18, 20 includes an elongate, straight leadscrew 26 having a rear end 26a and a front end 26b and whose exterior is provided with a helical screw thread. The leadscrew 26 has a longitudinal axis L that extends substantially parallel to the adjustment axis A-A. Annular rear and front stops 28a, 28b, made from rubber in this embodiment, are mounted at the rear and front ends 26a, 26b respectively of the leadscrew 26. The leadscrew 26 is rotatably mounted in a securing lug 30 at the rear end 26b. The securing lug 30 is attached to the outermost elongate tube 16 and is rotationally and translationally fixed relative thereto. The leadscrew 26 is also received within an internally threaded bore of a gearbox housing 32, which is secured to the intermediate elongate tube 18. The leadscrew 26 is rotatably mounted in a connector 36; 136 at the rear end 26a, wherein the connector 36; 136 is mounted to the innermost column tube 20 through an elongate slot 37 in the side wall of the intermediate tube 18, arranged parallel to the axis A-A, to allow longitudinal movement. The gearbox housing 32 includes an electric motor 34 secured thereto, and arranged to move the innermost, intermediate and outermost tubes 16, 18, 20 relative to one another along the adjustment axis A-A by driving the leadscrew 26.

As will described in greater detail below, the connector 36; 136 is configured to allow for translational and/or rotational adjustment of the leadscrew longitudinal axis L relative to the adjustment axis A-A.

io Figures 2 to 4 illustrate a first variant of connector 36 which forms part of steering column assembly 10 (Figure 1) in accordance with the invention. The connector 36 has a housing 38 formed in two parts 38a, 38b connected together by three bolts 40 each having a head comprising a hexagonal recess. The housing 38 is formed of metal and has a generally triangular cross-section when viewed in a plane transverse to the leadscrew longitudinal axis L, as shown in in Figure 3 in particular, wherein each of the vertices is rounded. Two lateral sides of the housing, an inner side 42a, and an outer side 42b are convex, whilst the third side 42c is concave in this embodiment. The inner side 42a is arranged so as to be located laterally inwardly of the leadscrew longitudinal axis L, in use, and the outer side 42b is arranged so as to be located laterally outwardly of the leadscrew longitudinal axis L. Each part of the housing 38a, 38b has a respective identical circular aperture 44 extending therethrough, the respective axes of which are coincident and parallel with the leadscrew longitudinal axis L. The circular apertures 44 are concentric and of equal diameter in this embodiment.

Each part of the housing 38a, 38b has a respective mounting flange 46 extending parallel to each other from the inner side of the housing 42a. The mounting flanges 46 are longitudinally spaced from one another in the direction of the leadscrew longitudinal axis L and are each integrally formed with the respective housing part 38a, 38b. Further, each mounting flange 46 includes an identical circular aperture 48 for receipt of an eccentric mounting screw 50. The apertures 48 are concentric and of equal diameter in this embodiment, and their respective axes extend parallel with the leadscrew longitudinal axis L. A mounting means, in the form of a mounting bracket 52, is configured to secure the housing 38 to a column tube of a steering column assembly 10 (Figure 1). The mounting bracket 52 is formed of metal and includes a pair of flanges 54a, 54b, each having a respective aperture 56a, 56b extending therethrough. Each respective aperture 56a, 56b is configured to receive a means for securing the mounting bracket 52 to a steering column assembly 10 (Figure 1). The mounting bracket 52 is configured to be translationally and rotationally fixed relative to a steering column assembly 10 (Figure 1). The longitudinal axis of each of the apertures 56a, 56b extends normal to the leadscrew longitudinal axis L. A mounting lug 58 having a width equal to the spacing of the mounting flanges 46 of the housing 38 interconnects the flanges 54a, 54b and extends normal therefrom to a rounded free end 58a and is received between the mounting flanges 46. The mounting lug 58 has an elongate circular aperture 60 extending parallel with the leadscrew longitudinal axis L. The apertures 48, 60 at least partially overlap such that the eccentric mounting screw 50 can extend therethrough so as to define a hinge to pivotably attach the housing 38 to the mounting bracket 52.

As is shown in Figures 3 and 4 in particular, the apertures 48 in the housing 38 have a smaller diameter than aperture 60 in the mounting lug 58. Therefore, in use, with eccentric mounting screw 50 extending through apertures 48, 60, pivotal and translational movement is permitted between the housing 38 and mounting bracket 52 so as to translationally and rotationally displace the leadscrew longitudinal axis L relative to the adjustment axis A-A (Figure 1) and the mounting bracket 52, as will be described in greater detail below in relation to Figures 5A to 7. The housing 38 is attached to the mounting bracket 52 such that it is rotationally fixed relative thereto about an axis normal to the leadscrew longitudinal axis L. An elongate elastomeric bushing 62 is located within the housing 38 and has an internally threaded aperture 64. The aperture 64 is concentric with, and has a smaller diameter than, apertures 44 of the housing 38. The internally threaded aperture 64 is configured to receive, and engage with, the external thread of the rear end 26a of leadscrew 26 (Figure 1), in use.

A bearing 66 is located between an internal surface of the housing 38 and an external surface of the elastomeric bushing 62 and is configured to facilitate smooth movement therebetween. The bearing 66 has a part-spherical inner surface 67 and is formed of a metal in this embodiment. The elastomeric bushing 62 is rotationally mounted within the bearing 66 which is, in turn, is fixedly mounted within the housing 38.

A protrusion, in the form of pin 68 extends from the outer surface of the elastomeric bushing 62 through an elongate, longitudinally extending slot 70 in the bearing 66. The elongate slot has its major axis substantially parallel with the leadscrew longitudinal axis L. The pin 68 is rotationally fixed relative to the elastomeric bushing 62 and together with the elongate slot 70 in the bearing 66 is configured to constrain the rotation of the elastomeric bushing 62 about an axis normal to the leadscrew longitudinal axis L, in the manner of a yawing io movement with respect to the axis L. The pin 68 and elongate slot 70 are also configured to prevent rotation of the bearing 66 and bushing 62 about the leadscrew longitudinal axis L (i.e. prevents a rolling movement with respect to the axis L), e.g. as the leadscrew 26 (Figure 1) is rotated when engaged with threads of the bushing 62, in use.

The bearing 66 and pin 68 allow for rotational displacement of the leadscrew longitudinal axis L relative to the adjustment axis A-A, as will be described in greater detail below in relation to Figures 8A to 9.

Figures 5A to 7 illustrate the translational displacement of the leadscrew longitudinal axis L between a first lateral position P and a second lateral position P. As is described above, the apertures 48, 60 at least partially overlap such that the eccentric mounting screw 50 extends therethrough so as to pivotably attach the housing 38 to the mounting bracket 52. The eccentric pivotal attachment, in addition to apertures 48 having a smaller diameter than longitudinally extending aperture 60, also results in lateral translational displacement of the leadscrew longitudinal axis L as the housing 38 pivots.

In Figures 5A and 6A, the centre of each aperture 48 is located proximate the 12 o'clock position of the longitudinally extending aperture 60 such that the leadscrew longitudinal axis L is located in the first lateral position P. As the housing 38 is pivoted relative to the mounting bracket 52 the eccentric pivot causes the centre of each aperture 48 to move towards the 3 o'clock position of the longitudinally extending aperture 60. The leadscrew longitudinal axis L is further away from the mounting bracket 52 when in the second lateral position P' relative to the first lateral position P. In use, the mounting bracket 52 is fixed relative to an adjustment axis A-A (Figure 7) of a steering column assembly 10 (Figure 7). Therefore, the leadscrew longitudinal axis L is displaced laterally relative to the adjustment axis A-A (Figure 7) when moved from the first lateral position P to the second lateral position P. Figures 8A to 9 illustrate the rotational displacement of the leadscrew longitudinal axis L between a first rotational position R, parallel with the adjustment axis A-A (Figure 9) and a second rotational position R' rotationally offset from, the first rotational position R. As is described above, elastomeric bushing 62 is rotationally mounted in the bearing 66 which is, in turn, fixedly mounted within the housing 38.

The leadscrew longitudinal axis L moves from the first rotational position R to the second rotational position R' as the elastomeric busing 62 is rotated within the bearing 66. In use, the mounting bracket 52 is fixed relative to an adjustment axis A-A (Figure 7) of a steering column assembly 10 (Figure 7) and the housing 38 is mounted on the bracket 52 by the eccentric pivot arrangement 48, 50, 60 and is prevented from rotating relative to the mounting bracket 52 about an axis normal to the leadscrew longitudinal axis L. Therefore, the leadscrew longitudinal axis L is rotated relative to the adjustment axis A-A (Figure 7) when the bushing 62 moves from the first rotational position R to the second rotational position R'.

As is described above, the connector 36 allows the leadscrew longitudinal axis L to displace laterally relative to the adjustment axis A-A and to rotate relative to the adjustment axis AA.

Therefore, in the case that one or more of the outermost, intermediate and innermost tubes 16, 18,20 (Figure 1) are misaligned, the connector 36 can compensate for the misalignment by allowing for adjustment of the axis of the leadscrew as the steering column assembly 10 (Figure 1) is telescopically adjusted. This can reduce frictional forces between the tubes 16, 18, 20 and reduce stress applied through the leadscrew.

Furthermore, the translation/rotation of the axis of the leadscrew also allows for a more reliable collapse of the steering column assembly 10 in the event of an impact, e.g. during a crash. Misalignment between one or more of the outermost, intermediate and innermost tubes 16, 18, 20 which may cause excess friction between components, and therefore an unpredictable collapse, can be compensated for by the connector 36.

Finally, the connector 36 can provide compensation for manufacturing intolerances between in one or more of the outermost, intermediate and innermost tubes 16, 18, 20 (Figure 1), thereby facilitating faster construction/assembly of the steering column assembly 10 (Figure 1).

Figures 10 to 12 illustrate a second variant of connector 136 which forms part of steering column assembly 10 (Figure 1) in accordance with the invention. Many features of the connector 136 are similar to corresponding features of the connector 36, wherein like features will be denoted by like reference numerals incremented by '100', where possible.

The connector 136 has a housing 138 formed in two parts 138a, 138b connected together by an adhesive in this embodiment and retained within a mounting frame 137. The housing 138 is formed of a plastic and has a generally teardrop shaped cross-section when viewed in a plane transverse to the leadscrew longitudinal axis L, as shown in in Figure 11 in particular. The housing 138 has a substantially cylindrical portion 139a having a radially projecting lobed portion 139b extending therefrom. The lobed portion 139b is arranged so as to be located on the opposite side of the leadscrew longitudinal axis L from the adjustment axis A-A (Figure 1).

Each part of the housing 138a, 138b has a respective identical circular aperture 144 extending therethrough, the respective axes of which are coincident and parallel with the leadscrew longitudinal axis L. The circular apertures 144 are concentric and of equal diameter in this embodiment.

The housing 138 is retained within a mounting frame 137 and is rotationally fixed relative thereto. The mounting frame 137 is formed of a metal and has a pair of mounting flanges 137a, 137b spaced from one another along the leadscrew longitudinal axis L such that the housing 138 is located therebetween. The mounting flanges 137a, 137b each have a generally teardrop shaped cross-section when viewed in a plane transverse to the leadscrew longitudinal axis L, matching the shape of the housing 138, but with a respective mounting portion 146a, 146b for attachment to the steering column, as will be explained.

The mounting portions 146a, 146b of the mounting flanges 137a, 137b are interconnected by an integrally formed connector plate 143 having a first lengthwise extending slot 143a in its radially outer face remote from the axis L and extending substantially parallel with the leadscrew longitudinal axis L and a second slot 143b in its face remote from the axis L and extending normal to and intersecting the first longitudinally extending slot 143a. Each mounting flange 137a, 137b has a respective identical circular aperture 141 extending therethrough. The circular apertures 139 are concentric and of equal diameter in this embodiment, and are also concentric with and of substantially the same diameter as circular apertures 144 of the housing 138.

Each mounting flange 137a, 137b also includes a further aperture 145 extending through the protrusion part of the teardrop cross-sectional shape. The apertures 145 are concentric o and of equal diameter in this embodiment and their respective axes extend parallel with the leadscrew longitudinal axis L. The lobed portion 139b of the housing 138 has a lengthwise extending slot 147 having a substantially oblong cross-sectional shape. In order to retain the housing 138 within the mounting frame 137, a guide pin, in the form of screw 140 having a head comprising a hexagonal recess extends through each of the apertures 145 and is received within the lengthwise extending slot 147 in the lobed portion 139b of the housing 138.

A mounting means, in the form of a mounting bracket 152 is configured to secure the housing 138 to a column tube of a steering column assembly 10 (Figure 1). The mounting bracket 152 is formed of a metal and is configured to be translationally and rotationally fixed relative to a steering column assembly 10 (Figure 1) and includes a mounting plate 154 having a first lengthwise extending projection 154a and a second projection 154b extending normal to and intersecting the first lengthwise extending projection 154a. The first and second projections 154a, 154b are received within respective first and second slots 143a, 143b in the connector plate 143 of the mounting frame 137 so as to locate the mounting frame 137 relative to the mounting bracket 152. In the present embodiment, an interference fit is provided between the first and second slots 143a, 143b and respective first and second projections 154a, 154b.

An aperture 156 extends through each of the connector plate 143 and the mounting bracket 152, proximate the intersection of the first and second slots 143a, 143b / first and second projections 154a, 154b and receives a mounting pin 149 for securing the connector 136 to a steering column assembly 10 (Figure 1). The aperture 156 extends substantially normal to the leadscrew longitudinal axis L. When the mounting pin 149 is received within the aperture 156, the mounting frame 137 is translationally and rotationally fixed relative to the mounting bracket 152.

As shown in Figure 14 in particular, the mounting bracket 152 includes a lug 157 extending forwardly from its front end having an aperture 157a extending substantially normal to the leadscrew longitudinal axis L. The respective centres of apertures 156 and 157a are aligned, and aperture 157a is configured to receive a mounting means for securing the connector 136 to a steering column assembly 10 (Figure 1).

As is shown in Figure 11 in particular, the depth of the slot 147 in the lobed portion 139b of the housing 138 is greater than the diameter of the screw 140 and the width of the slot 147 is the same as the diameter of the screw 140. Therefore, in use, with screw 140 extending through apertures 145 and engaged with slot 147 translational movement is permitted between the housing 138 and the mounting frame 137 as the screw 140 is moved radially along the slot 147. Further, as the mounting frame 137 is attached to the mounting bracket 152 such that it is translationally and rotationally fixed relative thereto, translational movement between the housing 138 and the mounting frame 137 results in translational displacement of the leadscrew longitudinal axis L relative to the adjustment axis A-A (Figure 1), as will be described in greater detail below in relation to Figures 16A to 17.

An elastomeric bushing 162 is located within the housing 138 and has an internally threaded aperture 164. The aperture 164 is concentric with, and has a smaller diameter than, apertures 144 of the housing 138. The internally threaded aperture 164 is configured to receive, and engage with, the external thread of the rear end 26a of leadscrew 26 (Figure 1), in use.

A bearing 166 is located between an internal surface of the housing 138 and an external surface of the elastomeric bushing 162. The bearing 166 is fixed with respect to the housing 138 and has an internal part-spherical bearing surface 167 which is complementarily shaped with an external part-spherical outer surface of the bushing 162, so that the bushing is rotatably mounted in the bearing.

A protrusion, in the form of pin 168, extends from the outer surface of the bushing 162 through an opening, in the form of an elongate slot 170 in the wall of the bearing 166. The bearing 166 and pin 168 allow for rotational displacement of the leadscrew longitudinal axis L relative to the adjustment axis A-A in the manner of a yawing movement, as will be described in greater detail below in relation to Figures 18A to 19.

The pin 168 and elongate slot 170 interact and function in a similar manner to the pin 68 and elongate slot 70 of the first variant, to prevent rotation of the axis L in a pitching or rolling movement and restricting the movement to a yawing movement, and in the interests of brevity will not be described further.

Figures 13 to 15 illustrate the arrangement of the housing 138, mounting frame 137 and bearing 166. As is shown in Figure 15, the housing 138 is in contact with the mounting flange 137a of the mounting frame 137. It will be appreciated that the housing 138 is also in contact with the other mounting flange 137b of the mounting frame. The housing 138 extends beyond both the bushing 162 and the bearing 166 along the longitudinal axis L, such that those components are out of contact with the mounting flange 137a and spaced therefrom by gap G. This arrangement can help reduce noise and vibration during normal operation as the plastic housing 138 can better absorb noise and vibration than the metal bearing 166, and the transmission path through the bearing 166 is removed.

Figures 16A to 17 illustrate the translational displacement of the leadscrew longitudinal axis L between a first position P (Figure 16A) and a second position P (Figure 16B). As is described above, the depth of the slot 147 is greater than the diameter of the screw 140 such that translational movement is permitted between the housing 138 and the mounting frame 137 as the screw 140 is moved along the slot 147, facilitating translational displacement of the leadscrew longitudinal axis L. In Figure 16A, the centre of each aperture 145 and the screw 140 is located proximate the open end of the longitudinally extending slot 147 such that the leadscrew longitudinal axis L is located in the first position P. If the housing 138 is displaced relative to the mounting frame 157 and mounting bracket 152 such that the centre of each aperture 145 and the screw is located proximate the base of the longitudinally extending slot 147 (Figure 16B), the leadscrew longitudinal axis L is consequently displaced from the first position P to the second position P. The leadscrew longitudinal axis L is further away from the mounting bracket 152 when in the second position P' relative to the first position P. In use, the mounting bracket 152 is fixed relative to an adjustment axis A-A (Figure 17) of a steering column assembly 10 (Figure 17). Therefore, the leadscrew longitudinal axis L is displaced relative to the adjustment axis AA (Figure 17) when moved from the first position P to the second position P. Figures 18A to 19 illustrate the rotational displacement of the leadscrew longitudinal axis L between a first rotational position R (Figure 18A), parallel with the adjustment axis A-A (Figure 19) and a second rotational position R' (Figure 18B) rotationally offset from, the first rotational position R. As is described above in respect of the first variant, elastomeric bushing 162 is rotationally mounted in the bearing 166 which is, in turn, is fixedly mounted within the housing 138.

If the elastomeric busing 162 is rotated within the housing 138, the leadscrew longitudinal axis L is consequently displaced from the first rotational position R to the second rotational position R'.. In use, the mounting bracket 152 is fixed relative to an adjustment axis A-A (Figure 19) of a steering column assembly 10 (Figure 19) and the housing 138 is rotationally fixed relative to the mounting bracket 152, via the mounting frame 157, about an axis normal to the leadscrew longitudinal axis L. Therefore, the leadscrew longitudinal axis L is rotated relative to the adjustment axis A-A (Figure 19) when moved from the first rotational position R to the second rotational position R'.

As is described above, the connector 136 allows the leadscrew longitudinal axis L to displace laterally relative to the adjustment axis A-A and to rotate relative to the adjustment axis A-A. The connector 136 also provides similar advantages to those of connector 36, described above.

Therefore, in the case that one or more of the outermost, intermediate and innermost tubes 16, 18, 20 (Figure 1) are misaligned, the connector 136 can compensate for the misalignment by allowing for adjustment of the axis of the leadscrew as the steering column assembly 10 (Figure 1) is telescopically adjusted. This can reduce frictional forces between the tubes 16, 18, 20 and reduce stress applied through the leadscrew.

Furthermore, the translation/rotation of the axis of the leadscrew also allows for a more reliable collapse of the steering column assembly 10 in the event of an impact, e.g. during a crash. Misalignment between one or more of the outermost, intermediate and innermost tubes 16, 18, 20 which may cause excess friction between components, and therefore an unpredictable collapse, can be compensated for by the connector 136.

Finally, the connector 136 can provide compensation for manufacturing intolerances between in one or more of the outermost, intermediate and innermost tubes 16, 18, 20 (Figure 1), thereby facilitating faster construction/assembly of the steering column assembly 10 (Figure 1).

The invention is not restricted to the details of the foregoing embodiments.

It will be appreciated by those skilled in the art that several variations to the aforementioned embodiments are envisaged without departing from the scope of the invention.

It will also be appreciated by those skilled in the art that any number of combinations of the aforementioned features and/or those shown in the appended drawings provide clear advantages over the prior art and are therefore within the scope of the invention described herein.

Claims

CLAIMSA connector for attaching a linear actuator to a steering column of a vehicle, the connector comprising: a mounting means configured to be secured to a tube of a steering column; a housing attached to the mounting means and comprising a threaded aperture for receipt of a leadscrew of a linear actuator; wherein the position of the aperture is displaceable translationally and/or rotationally with respect to the mounting means.
2. A connector according to claim 1, comprising a bushing received within the housing, wherein the bushing comprises the aperture for receipt of a lead screw of a linear actuator.
3. A connector according to claim 2, wherein the bushing is rotatable within the housing to allow the position of the aperture to be displaced relative to the mounting means.
A connector according to claim 3, wherein the bushing is rotatable about an axis normal to a longitudinal axis of the aperture.
5. A connector according to any one of claims 2 to 4, comprising a bearing located between the bushing and the housing.
A connector according to claim 5, wherein the bearing is rotationally fixed with respect to the housing.
A connector according to any one of claims 2 to 6, wherein the bushing is displaceable translationally relative to the mounting means and/or housing to allow the position of the aperture to be displaced translationally with respect to the mounting means.
8. A connector according to any one of claims 2 to 7, wherein the bushing comprises a protrusion received in a recess to limit the rotational displacement of the bushing with respect to the housing
9. A connector according to claim 8 when appendant to claim 5, wherein the recess is provided in the bearing.
10.
11.
12.
13.
14.A connector according to claim 8 or claim 9, wherein the recess comprises an elongate slot.A connector according to claim 10, wherein the elongate slot extends substantially parallel with a longitudinal axis of the aperture.A connector according to any preceding claim, wherein the housing is movable relative to the mounting means so as to displace the position of the aperture translationally and/or rotationally relative thereto.A connector according to any preceding claim, wherein the housing is pivotably attached to the mounting means.A connector according to claim 13, wherein the housing is attached to the mounting means via a hinge, wherein the hinge comprises a first aperture extending through the housing, a second aperture extending through the mounting means and a pin extending through each of the first aperture and second aperture, wherein the second aperture has a diameter greater than the first aperture.
15. A connector according to any preceding claim, wherein the mounting means comprises a mounting frame having a pair of longitudinally spaced flanges, wherein the housing is located between the flanges and is displaceable with respect thereto.
16. A connector according to claim 15, wherein the housing comprises a slot and the mounting frame comprises a guide pin extending between the longitudinally spaced flanges, wherein the guide pin is received within the slot and is configured to move radially therealong as the housing is displaced relative to the mounting frame.
17. A connector according to any one of claims 1 to 11, wherein the housing is fixedly attached to the mounting means.
18. A connector according to claim 17, wherein the housing is attached to the mounting means in an interference fit.
19. A connector according to any preceding claim, wherein the housing defines a two-part construction, formed as a pair of connected parts.
20. A connector according to any preceding claim, wherein the steering column comprises a plurality of telescopic tubes, the linear actuator comprises a rotatable leadscrew and the steering column is adjustable in length along an adjustment axis by operation of the linear actuator.
21 A steering column assembly for a vehicle, comprising: io a plurality of telescopic tubes mounted so as to be moveable relative to one another along an adjustment axis; a linear actuator comprising a rotatable leadscrew configured to move the telescopic tubes relative to one another; wherein the steering column is adjustable in length along the adjustment axis by operation of the linear actuator; and a connector attaching the linear actuator to one of the plurality of telescopic tubes, the connector comprising: a mounting means secured to one of the plurality of telescopic tubes; a housing attached to the mounting means and comprising a threaded aperture, wherein the leadscrew of the linear actuator is received within the threaded aperture; wherein the position of the aperture is displaceable translationally and/or rotationally with the respect to the adjustment axis so as to displace a longitudinal axis of the leadscrew with respect to the adjustment axis.
22. A vehicle comprising a connector according to any one of claims 1 to 20 or a steering column assembly according to claim 21.