The present invention relates to an adjustable steering column for a motor vehicle, the steering column comprising at least two structural parts and at least one securement device. The structural parts, in an opened position of the securement device, are displaceable in their position relative to one another along a displacement path and, in a closed position of the securement device, are secured in position relative to one another. At least on a first of the structural parts, a stop element is disposed which delimits the displacement path and, upon a force value being exceeded, is detachable from the first of the structural parts.
Such adjustable steering columns are known within prior art. The displaceability of the two structural parts relative to one another serves, for example, for the purpose of enabling adapting the position of the steering wheel to a particular driver. Within prior art height and/or length-adjustable steering columns are known. If the structural parts of the steering column are to be displaced relative to one another, the securement device is moved into its opened position. When the desired setting or position relative to one another has been reached, the securement device is moved into the closed position in which the two structural parts of the adjustable steering column are secured in position relative to one another.
To exclude faulty operation and to delimit the displacement path in the opened securement device, it is known to provide on one of the two structural parts a stop element delimiting the displacement path. In order to abolish this delimitation in the event of a motor vehicle collision, thus in the event of a crash, it is known to implement this stop element such that it is detachable when a force value is exceeded. In prior art the term break-away elements is also frequently used.
A steering column of said type is disclosed, for example, in U.S. Pat. No. 7,703,804 B2. This publication discloses an adjustable steering column in which the displacement path is carried along a displacement region in the form of an elongated hole. In the event of a motor vehicle crash upon a predefinable force value being exceeded, a stop element is disengaged which, initially, had been secured on a steering column bearing unit, such that the steering column is displaceable along an expanded path which adjoins the displacement path. Such a solution is complex since the stop element must be suitably secured and the break-away force must be set. A further significant disadvantage comprises that a corresponding securement pin must be broken off which leads to a relatively high force peak at the beginning of the crash sequence. In the event of a crash this force peak can have a negative effect on the driver of the motor vehicle.
Another generic adjustable steering column is disclosed in DE 10 2007 002 091 A1. Here a stop element is also provided for delimiting the displacement path, which, when a predefined force value is exceeded, breaks off in the form of a break-away element and enables the path for a further axial dislocation of the steering spindle bearing unit relative to the chassis-stationary bracket unit. Here there is also the disadvantage that the break-away element, since it must withstand the occurring forces even in the case of faulty operation, at the beginning of the crash generates a relatively high force peak which is undesirable since it can lead to unnecessary injuries of the driver of the motor vehicle.
The invention addresses the problem of improving the generic adjustable steering column to the extent that the force peaks occurring during the detachment of the stop element are avoided or at least decreased.
This problem is resolved through an adjustable steering column according as described herein. The dependent claims describe features of preferred physical forms of the invention.
Consequently, there is provided that the adjustable steering column comprises a tool which for detaching the stop element at least regionally can be introduced between the stop element and the first of the structural parts. A fundamental concept is thus that the stop element no longer must, as is the case in prior art, be broken off via a blunt stop which leads to the undesired force peak, but rather this force peak is markedly reduced or avoided thereby that the tool is introduced, preferably slid in between the stop element and the first structural part, on which the stop element is initially secured. It can herein be provided that the tool during the introduction between the stop element and the first of the structural part pries and/or shears the stop element off the first of the structural parts. It is furthermore advantageous if on the tool and/or in the proximity of the stop element, onto which the tool impinges during the detachment of the stop element, a preferably wedge-shaped oblique face or oblique surface area or face or point is disposed. As is also the case in generic adjustable steering columns, it is herein provided that the stop element upon actuation below a preferably predefinable force value delimits the displacement path between the two structural parts and only upon reaching or exceeding the preferably predefinable force path, in particular in the event of a crash, a detachment of the stop element from the first of the structural parts takes place.
Preferred physical forms of the invention provide that the tool, at least during the detachment of the stop element from the first of the structural parts, is braced or supported, preferably is secured, on the other of the structural parts. The tool does not need to be herein absolutely supported directly on the other of the structural parts. It can also be provided that the tool is supported via a further structural part, for example an intermediate piece between the two structural parts, on the other structural part. It is generally feasible that the tool, relative to the other of the structural parts, is permanently nonmovably supported on the other of the structural parts, preferably is secured, thus fixed on the other of the structural parts. However, it is equally well feasible that the tool is supported only temporarily nonmovably, preferably secured, with respect to the other structural part on the latter. It can thus be provided that the tool relative to the other of the structural parts in only one engagement position of an engagement element is nonmovably supported, preferably secured, on the other of the structural parts, with the engagement element also comprising a detached position in which the tool is movable relative to the other of the structural parts.
The stop element advantageously comprises at least one stop face with which, upon reaching an end of the displacement path, it abuts on the other of the structural parts or a further structural part connected therewith.
On the stop face can be disposed at least one, preferably elastic, buffer or cushion for dampening the abutment. These cushions can be laid out in particular such that during an improper faulty operation at opened securement device, in which the two structural parts of the steering column are unusually forcefully moved relative to one another such that a vigorous abutment on the stop element occurs, they can cushion without a detachment of the stop element from the first of the structural parts occurring.
It is furthermore advantageous if the tool for detaching the stop element from the first of the structural parts does not act on the stop faces onto the stop element. This can be attained, for example, thereby that the tool for detaching the stop element from the first of the structural parts can be introduced in a region outside of the stop face between the stop element and the first of the structural parts.
The stop element can be a synthetic material part. It can be produced using an injection molding method. The synthetic material part can be comprised of a single material, but also of a combination of several materials. These can be produced, for example, in single- or multi-component injection molding. It is for example conceivable to implement the cushions of the stop element of another, in particular softer, material than the remaining stop element.
The stop element can be anchored by means of at least one peg on or in the first of the structural parts. The pegs can be fixedly disposed on the stop element and engage into corresponding openings in the first of the structural parts or conversely. It can also be provided for the peg or pegs to be formed integrally onto the stop element or the first of the structural parts, which, at least in the case of the stop element, can also be produced using single- or multi-component injection molding.
However, alternatively it is also conceivable and feasible to produce the stop element of metal, for example using an aluminum pressure die casting method. Due to the technology according to the invention, a high force peak at the beginning of the crash is nevertheless avoided herein.
Preferred physical forms of the invention provide that the tool is preferably a tab which is a part of an energy absorption device of the adjustable steering column, and the energy absorption device, at least in the event of a motor vehicle crash, connects at least the two structural parts of the steering for the absorption of energy. The energy absorption device and the securement device can herein be implemented such that they are integrated, however, they can also be implemented separately from one another. In its closed position, the securement device can, as is known per se, establish a connection under friction and/or under form closure between the two structural parts of the adjustable steering column.
Technically especially simply realizable physical forms of the invention provide that the stop element is disposed outwardly projecting on an outer surface of the first of the structural parts and the tool for detaching the stop element can be introduced between the stop element and the outer surface of the first of the structural parts. This comprises in particular also the case that the stop element is disposed entirely outside of an elongated hole.
Preferred physical forms of adjustable steering columns according to the invention provide that at least one of the structural parts is a bracket unit intended for the chassis-stationary fixing on the motor vehicle and the second of the structural parts is a steering spindle bearing unit held by the bracket unit for the rotatable bearing of a steering spindle. The steering spindle bearing unit in the opened position of the securement device is displaceable with respect to the bracket unit and, in the closed position of the securement device, is secured in its position relative to the bracket unit. Herein, the first of the structural parts on which the stop element is disposed can be the bracket unit and the other of the structural parts can be the steering spindle bearing unit. The converse implementation is also conceivable, in which the first of the structural parts is the steering spindle bearing unit and the other of the structural parts is the bracket unit.
The connection with the bracket unit can be established indirectly, for example via a clamp bolt known within prior art.
Further features and details of preferred physical forms of the invention will be explained in conjunction with embodiments selected as examples and depicted in the Figures, in which:
Like or identically acting elements are denoted in the Figures by the same reference numbers.
The depicted steering column 1 is in any case height-adjustable in the opened position of the securement device 4 in the direction 36 as well as also length-adjustable in the direction 35. It is understood that there are also embodiments of the invention in which the steering column 1 is only height-adjustable or only length-adjustable.
Apart from the securement device 4, the depicted embodiment of the steering column 1 according to
In the depicted embodiment, the energy absorption device 10 is thus integrated into the securement device 4. This does not absolutely need to be the case. All other energy absorption mechanisms known within the prior art can also be applied in steering columns implemented according to the invention. These can be integrated into the securement device 4. However, they can also be implemented separately therefrom.
According to the invention in the steering column 1 discussed up to now, a stop element 5 is provided for delimiting the displacement path between structural part 2 and 3 and a tool 6, the tool 6 of the steering column 1 in the event of a crash being introduced between the stop element 5 and the first structural part 2, in order to detach the stop element 5 from the first structural part 2 under avoidance or at least marked reduction of force peaks. In the depicted variant according to the first embodiment the tool 6 is implemented as a portion of a tab, namely of the tearing flex tab 9. The tab, of which the tool 6 forms a portion, can alternatively be a flex tab 8 or a pure tearing tab. In the first embodiment the tool 6 specifically is the end of the tearing flex tab 9 oriented toward the steering wheel connection 16. In terms of avoidance of force peaks, it is advantageous if, as is the case in the depicted embodiment, the tool 6 is implemented as a wedge-shaped or, viewed with respect to the direction 35, oblique surface area or face 27a or point. In addition, or alternatively, a corresponding oblique face 27b can also be disposed in that region on the stop element 5 in which in the event of a crash the tool 6 impacts on the stop element 5. In the specifically depicted embodiment, as is provided in general in advantageous implementations, the stop element 5 is disposed outwardly projecting on an outer surface 12 of the first structural part 2 and the tool 6 for the detachment of the stop element 5 is introducible between the stop element 5 and the outer surface 12 of the first structural part 2. Through this introduction or sliding-in of the tool 6 between stop element 5 and first structural part 2, the stop element 5 is pried and/or sheared off from the first structural part 2 whereby the undesired force peaks during the detachment of the stop element 5 from structural part 2 are avoided or at least markedly reduced. It is to be preferred that the stop element 5 is pried off from the first structural part 2, especially preferred under avoidance of a shearing or breaking operation, for further lowering of the undesired force peaks during the detachment.
In the case of a crash according to
In
In terms of form and material selection, the cushions 14 can be implemented differently. They can be elastic hollow bodies as in the depicted embodiment. Other suitable elastic materials, however, can also be employed. Preferred implementations provide that the stop element 5 as well as the cushions comprise synthetic material. In order for the cushions 14 to be made correspondingly softer than the remaining stop element 5, a softer synthetic material, for example, can be utilized. Such parts can be readily produced using known injection molding methods; in particular, multi-component injection molding. In the depicted embodiment, the cushions are each provided with a correspondingly thin wall thickness such that they can yield elastically.
If the driver displaces the structural part 2 of the steering column 1 so far that the cushions 14 on the stop element 5 abut the further structural part 29 or structural part 3 without exerting any excessive force for the displacement, the cushions 14 are maintained in their full resilient length. If, in the event of a crash, the effect of a higher force occurs, the cushions 14 are compressed and simultaneously the tool 6 is pushed in the direction of the steering wheel connection 16 such that the stop element 5, as shown in
In
In the fourth embodiment, the tool 6 is also implemented as a portion of a tab. In the specifically shown case this is a flex tab 8. One end of the tab 8 is fixed on the second structural part 2 by means of a fixing fastener 33. The flex tab 8 comprises a deflection or recurvature 11. The tool 6 is located at another end of the tab 8 opposite the fixing fastener 33. A holding-down device 34 is secured on structural part 2 and ensures that the flex tab 8 is at least in the proximity of the tool 6 in contact on the outer surface 12 of structural part 2.
The fourth embodiment is a variant according to the invention in which the tool 6 is connected interactively preferably with a bent over region of a tab. The tool 6, at least during the detaching of the stop element 5 from the first of the structural parts 2, is supported (preferably secured) by means of the recurvature 11 on the other of the structural parts 3.
In the embodiment depicted in
For the sake of completeness reference is made to the fact that the corresponding recurvature 11 with the transmission function can also be attained through a traction cable or the like.
It is also in principle conceivable and feasible in the fourth embodiment to lower the force peak during the prying-out through corresponding cushion elements 14 as illustrated in the embodiment according to
To the extent applicable or implementable all of the different individual features of the several examples can be interchanged and/or combined without leaving the scope of the invention.
Number | Date | Country | Kind |
---|---|---|---|
10 2010 017 622 | Jun 2010 | DE | national |
10 2010 036 891 | Aug 2010 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/EP2011/002676 | 5/31/2011 | WO | 00 | 12/27/2012 |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2012/000593 | 1/5/2012 | WO | A |
Number | Name | Date | Kind |
---|---|---|---|
4793204 | Kubasiak | Dec 1988 | A |
4900178 | Haldric et al. | Feb 1990 | A |
5029489 | Burmeister et al. | Jul 1991 | A |
5320384 | Arnold et al. | Jun 1994 | A |
5524927 | Toussaint | Jun 1996 | A |
5547221 | Tomaru et al. | Aug 1996 | A |
5580091 | Doty | Dec 1996 | A |
5606892 | Hedderly | Mar 1997 | A |
6095012 | Lutz | Aug 2000 | A |
6139057 | Olgren et al. | Oct 2000 | A |
6276719 | Gärtner | Aug 2001 | B1 |
6378903 | Yabutsuka et al. | Apr 2002 | B1 |
6394241 | Desjardins et al. | May 2002 | B1 |
6592148 | Byers et al. | Jul 2003 | B2 |
7422239 | Ishibashi et al. | Sep 2008 | B2 |
7685903 | Streng et al. | Mar 2010 | B2 |
7703804 | Cymbal et al. | Apr 2010 | B2 |
7721620 | Matsui et al. | May 2010 | B2 |
7866699 | Levin et al. | Jan 2011 | B2 |
7891268 | Park | Feb 2011 | B2 |
7896395 | Cymbal et al. | Mar 2011 | B2 |
8408089 | Oshita et al. | Apr 2013 | B2 |
20010019205 | Ikeda et al. | Sep 2001 | A1 |
20030000330 | Murakami et al. | Jan 2003 | A1 |
20040232685 | Gatti et al. | Nov 2004 | A1 |
20060090586 | Lee | May 2006 | A1 |
20060181070 | Imamura et al. | Aug 2006 | A1 |
20060243089 | Cymbal et al. | Nov 2006 | A1 |
20060290128 | Ridgway et al. | Dec 2006 | A1 |
20070137377 | Kamei | Jun 2007 | A1 |
20070252372 | Spano et al. | Nov 2007 | A1 |
20080191457 | Ridgway et al. | Aug 2008 | A1 |
20080229867 | Waibel et al. | Sep 2008 | A1 |
20080257097 | Graf | Oct 2008 | A1 |
20080284150 | Yamada | Nov 2008 | A1 |
20090013817 | Schnitzer et al. | Jan 2009 | A1 |
20090031843 | Marable et al. | Feb 2009 | A1 |
20090145258 | Davies et al. | Jun 2009 | A1 |
20100018340 | Schnitzer et al. | Jan 2010 | A1 |
20100031768 | Oshita et al. | Feb 2010 | A1 |
20100275721 | Davies et al. | Nov 2010 | A1 |
20100282016 | Oehri et al. | Nov 2010 | A1 |
20100300236 | Goulay et al. | Dec 2010 | A1 |
20100300237 | Ridgway et al. | Dec 2010 | A1 |
20100300238 | Ridgway et al. | Dec 2010 | A1 |
20110041642 | Havlicek | Feb 2011 | A1 |
20110115206 | Sulser et al. | May 2011 | A1 |
20110174028 | Bahr et al. | Jul 2011 | A1 |
20110210537 | Uesaka | Sep 2011 | A1 |
20110271787 | Marable et al. | Nov 2011 | A1 |
20120024101 | Schnitzer et al. | Feb 2012 | A1 |
20120125139 | Tinnin et al. | May 2012 | A1 |
20120266716 | Sulser et al. | Oct 2012 | A1 |
20130074641 | Schnitzer et al. | Mar 2013 | A1 |
20130327176 | Domig et al. | Dec 2013 | A1 |
Number | Date | Country |
---|---|---|
28 21 707 | Nov 1978 | DE |
39 14 608 | Oct 1990 | DE |
10 2005 052 123 | Jan 2007 | DE |
10 2007 002 091 | Jul 2008 | DE |
10 2007 003 091 | Aug 2008 | DE |
60 2004 012 021 | Mar 2009 | DE |
10 2008 007 094 | Sep 2009 | DE |
10 2008 007 093 | Nov 2009 | DE |
10 2010 061 268 | Jun 2012 | DE |
0 179 690 | Apr 1986 | EP |
0 323 298 | Jul 1989 | EP |
0 537 454 | Nov 1995 | EP |
0 641 705 | Jan 1997 | EP |
0 802 104 | Oct 1997 | EP |
1 464 560 | Oct 2004 | EP |
10 2004 051 060 | Jan 2006 | EP |
1 125 820 | Mar 2008 | EP |
1 955 921 | Aug 2008 | EP |
1 975 036 | Oct 2008 | EP |
2 022 699 | Feb 2009 | EP |
2 781 748 | Feb 2000 | FR |
2 840 869 | Dec 2003 | FR |
2 881 707 | Aug 2006 | FR |
1 584 984 | Feb 1981 | GB |
2 288 154 | Oct 1995 | GB |
2 291 840 | Feb 1996 | GB |
2 311 839 | Oct 1997 | GB |
2 454 345 | May 2009 | GB |
62-161081 | Oct 1987 | JP |
07-117685 | May 1995 | JP |
9-2294 | Jan 1997 | JP |
2004-67012 | Mar 2004 | JP |
2006-096120 | Apr 2006 | JP |
2008071306 | Jun 2008 | WO |
2008083811 | Jul 2008 | WO |
2008142312 | Nov 2008 | WO |
2009147325 | Dec 2009 | WO |
2010000980 | Jan 2010 | WO |
WO 2010009486 | Jan 2010 | WO |
Entry |
---|
International Search Report issued Dec. 15, 2011 in International (PCT) Application No. PCT/EP2011/002676. |
German Search Report dated Mar. 15, 2011 in German Application No. DE 10 2010 017 622.2. |
German Search Report dated Mar. 18, 2011 in German Application No. DE 10 2010 036 891.1. |
U.S. Office Action dated Apr. 11, 2014 issued in U.S Appl. No. 13/994,213. |
Number | Date | Country | |
---|---|---|---|
20130118292 A1 | May 2013 | US |