Title: Steering column with a locking device
Abstract: A steering column includes a locking device for securing a jacket tube in a predetermined and adjustment position and having a first locking member with an engagement member received in an at least one hole provided in the first locking member and displaceable between a first position in which it projects beyond the first locking member by a predetermined length, and a second position in which it is displaced into the at least one hole against a biasing force of a spring located in the hole, and a second locking member having a plurality of receiving holes associated with the at least one engaging member and spaced from the first locking member, in opened and closed positions of the locking device, respectively, by a distance which is grater or smaller than the predetermined length by which the engaging member projects in its first position beyond the first locking member.
Patent Number: 6,848,716 Issued on 02/01/2005 to Lutz
| Inventors:
|
Lutz; Christian (Nuziders, AT)
|
| Assignee:
|
ThyssenKrupp Presta Aktiengesellschaft (Eschen, LI)
|
| Appl. No.:
|
618815 |
| Filed:
|
July 14, 2003 |
Foreign Application Priority Data
| Jul 16, 2002[DE] | 102 32 041 |
| Current U.S. Class: |
280/775; 74/493 |
| Intern'l Class: |
B62D 001/18 |
| Field of Search: |
280/775,777,779
74/493
|
References Cited [Referenced By]
U.S. Patent Documents
| 5606891 | Mar., 1997 | Tisell et al.
| |
| 5787759 | Aug., 1998 | Olgren | 74/493.
|
| 5988679 | Nov., 1999 | Schelling et al.
| |
| 6092957 | Jul., 2000 | Fevre et al. | 403/373.
|
| 6095012 | Aug., 2000 | Lutz.
| |
| 6450531 | Sep., 2002 | Rinker et al. | 280/775.
|
| 6623036 | Sep., 2003 | Yamamura et al. | 280/775.
|
| 6659504 | Dec., 2003 | Riefeet al. | 280/777.
|
| Foreign Patent Documents |
| 0121506 | Oct., 1984 | EP.
| |
| 0440698 | Sep., 1991 | EP.
| |
Primary Examiner: Dickson; Paul N.
Assistant Examiner: To; Toan C
Attorney, Agent or Firm: Sidley Austin Brown & Wood, LLP
Claims
What is claimed is:
1. A steering column comprising:
a steering gear shaft;
a jacket tube for receiving at least section of the steering gear shaft;
a locking device having a closed position in which the jacket tube is
fixedly secured to a bracket member, and an open position in which the
jacket tube is displaceable, within predetermined limits, relative to the
bracket member; and
a pull device for opening and closing the locking device,
wherein the locking device has a first locking member having at least one
hole, an engagement member displaceably received in the at least one hole
and displaceable between a first position in which it projects beyond the
first locking member by a predetermined length, and a second position in
which it is displaced into the at least one hole against a biasing force
of a spring located in the hole, and a second locking member having a
plurality of receiving holes associated with the at least one engaging
member, and
wherein in the open and closed positions of the locking device, a distance
between the first and second locking members is, respectively, greater and
smaller than the predetermined length by which the engaging member
projects, in the first position thereof, beyond the first locking member.
2. A steering column as set forth in claim 1, wherein the first and second
locking members are pressed against each other in the closed position of
the locking device.
3. A steering column as set forth in claim 1, wherein the first locking
member has at least two engaging members, and the second locking member
has receiving holes associated with each of the at least two engaging
members.
4. A steering column as set forth in claim 1, further comprising a locking
bolt that extends through at least one opening in the bracket member and
at least one opening in the jacket tube, and that cooperates with the pull
device.
5. A steering column as set forth in claim 4, wherein at least one of the
at least one opening of the bracket member and the at least one opening of
the jacket tube is formed as an elongate opening.
6. A steering column as set forth in claim 5, wherein the receiving holes
of the second locking members are arranged in a row one after another and
have centers thereof located on al straight line extending parallel to a
longitudinal extent of the elongate opening.
7. A steering column as set forth in claim 6, wherein the second locking
member has at least two rows of receiving holes associated with the at
least one engaging member and located, respectively, on opposite sides of
the elongate opening.
8. A steering column as set forth in claim 7, wherein the second locking
member has at least two rows of receiving holes located on each side of
the elongate opening.
9. The steering column as set forth in claim 1, further comprising at least
one spring for retaining the first and second locking members in a spaced
relationship to each other in the open position of the locking device.
10. The steering column as set forth in claim 9, wherein the first locking
member has at least one projection projecting into an elongate opening
formed in the second locking member, and wherein the at least one
retaining spring is arranged in the at least one projection.
11. A steering column as set forth in claim 1, wherein the at least one
engaging member has a bevel at a free end thereof.
12. A steering column as set forth in claim 1, wherein the first locking
member has a body and the at least one hole is provided in the body, and
wherein the locking device further comprises a cover plate located on a
side of the body remote from the second locking member for closing the at
least one hole.
13. A steering column as set forth in claim 12, wherein the at least one
hole has, in a region adjacent to the second locking member, a section
with a smaller diameter and forming a stop shoulder, and wherein the at
least one engaging member has an annular flange cooperating with the stop
shoulder for retaining the at least one engaging member in the at least
one hole.
14. A locking device for a steering column having a jacket tube for
receiving at a least a section of a steering gear shaft, and a bracket
member for securing the steering column to a body of a motor vehicle, the
locking device having a closed position in which the jacket tube is
fixedly secured to the bracket member, and an open position in which the
jacket tube is displaceable, within predetermined limits, relative to the
bracket member, the locking device comprising:
a first locking member having at least one hole and an engagement member
displaceably received in the at least one hole and displaceable between a
first position in which it projects beyond the first locking member by a
predetermined length, and a second position in which it is displaced into
the at least one hole against a biasing force of a spring located in the
hole; and a second locking member having a plurality of receiving holes
associated with the at least one engaging member,
wherein in the open and closed positions of the locking device, a distance
between the first and second locking members is, respectively, greater and
smaller than the predetermined length by which the engaging member
projects in the first position thereof beyond the first locking member.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a steering column including a jacket tube
for receiving at least a section of a steering gear shaft, a bracket
member for securing the steering column to a body of a motor vehicle, and
a locking device having a closed position in which the jacket tube is
fixedly secured to the bracket member, and an open position in which the
jacket tube is displaceable, within predetermined limits, relative to the
bracket member.
2. Description of the Prior Art
Different embodiments of a steering column, which is described above, are
well known. Usually, in the open position of the locking device, both the
length of the steering column and its inclination or height can be
adjusted. For fixing the jacket tube in the closed position of the locking
device, crossing each other, packs of lamellas are provided one of which
is secured to the bracket tube and another of which is secured on the
bracket member. The lamella packs are pierced by a locking bolt which is
tensioned by a pull device. A steering column of the type described above
is disclosed, e.g., in European Publication EP 0 802 104 B1. For effecting
the necessary adjustment, crossing each other elongate openings are
provided in the lamella packs, in the jacket tube, and in the bracket
member, with the locking bolt extending through the elongate openings.
Locking devices with lamellas or lamella-like elements are discloses,
e.g., in European Publications EP 121 506 B1; EP-0 440 698 B1 and U.S.
Pat. No. 5,606,891. The drawback of the steering columns, which including
locking devices with lamellas, consists in that for obtaining a high
retaining force in the closed position of the locking device, a relatively
large number of lamellas is required. This results in that for adjusting
the steering column in the open position of the locking device, a
relatively large friction force has to be overcome.
European Publication EP-0 836 981 B1 discloses an adjustable steering
column the locking device of which has toothed members the teeth of which
engage each other in the closed position of the locking device. With this
locking device, the adjustment of the steering column in the open position
of the locking device can be effected rather easily. However, with the
locking device of this type, there can be cases when the tips of opposite
teeth are located directly opposite each other, and upon closing of the
device, it cannot be properly closed. In case of a crash, an uncontrolled
displacement of the steering column can take place. Furthermore, in case
the tips of the teeth are located directly opposite each other, the device
cannot be closed at all or is closed incompletely, and/or requires
application of a substantial force for closing.
Accordingly, an object of the present invention is a steering column of the
type discussed above and that can be easily adjusted in the open position
of the locking device.
Another object of the present invention is a steering column of the type
described above and the locking device of which can be easily closed in
any of adjustment positions of the steering column.
SUMMARY OF THE INVENTION
These and other objects of the present invention, which will become
apparent hereinafter, are achieved by providing a steering column the
locking device of which includes a first locking member having at least
one hole, an engagement member displaceably received in the at least one
hole and displaceable between a first position in which it projects beyond
the first locking member by a predetermined length, and a second position
in which it is displaced into the at least one hole against a biasing
force of a spring located in the hole, and a second locking member having
a plurality of receiving holes associated with the at least one engaging
member and wherein in the opened and closed positioned of the locking
device a distance between the first and second locking members is,
respectively, greater and smaller than the predetermined length by which
the engaging member projects in its first position beyond the first
locking member.
With the inventive locking device, in the closed position of the device,
the at least one engaging member of the first locking member engages in an
opposite receiving hole of the second locking member corresponding to a
selected adjustment position of the locking device. If in the selected
adjustment position, no receiving hole is located opposite the engaging
member, the pull device can still be closed, as the engaging member is
pushed further in its hole in the first locking member, with its free end
abutting the surface of the second locking member between the receiving
holes. When later, a force is applied to the steering gear shaft of the
steering column, whether during a normal operation or in case of a crash,
the force would lead to a small displacement of the two locking members
relative to each other so that the engaging member would be able to engage
in a respective receiving hole of the second locking member as soon as it
finds itself opposite the respective receiving hole, whereby a further
change of the position of the steering column is prevented.
According to an advantageous embodiment of the present invention, the first
locking member includes a plurality of engaging members to each of which a
plurality of receiving holes in the second locking members is assigned.
Thereby, the length of the path between two adjustment positions of a
steering column, in which a respective engagement member engages in a
respective hole, can be made very short.
The novel features of the present invention, which are considered as
characteristic for the invention, are set forth in the appended claims.
The invention itself, however both as to its construction and its mode of
operation, together with additional advantages and objects thereof, will
be best understood from the following detailed description of preferred
embodiments, when read with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The drawings show:
FIG. 1 a side view of a section of a steering column according to the
present invention illustrating the inventive parts of the column;
FIG. 2 a side view of another side of the inventive steering column;
FIG. 3 a cross-sectional view along line 3--3 in FIG. 1;
FIG. 4 a cross-sectional view of a portion of the view shown in FIG. 3 at
an increased scale;
FIG. 5 a bottom partially cross sectional view along line 5--5 in FIG. 2;
FIG. 6 a view showing a section of the view shown in FIG. 5 at an increased
scale;
FIG. 7 a view showing a section of a steering column shown in FIG. 6 in a
closed position of the locking device;
FIG. 8 an exploded view showing first and second locking members; and
FIG. 9 a partial cross-sectional view showing first and second locking
members in the locking position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A steering column according to the present invention, which is shown in
FIGS. 1-7, has a bracket member 1 which is secured to a section of a
vehicle body. The bracket member 1 has two legs 2 projecting downward and
between which a jacket tube 3, which has parallel side sections, lies. A
section of a steering gear shaft 4 is received in the jacket tube 3 and is
rotatably supported therein. A steering wheel is secured on a front end 5
of the steering gear shaft 4. The opposite end of the steering gear shaft
4 is connected with other sections of the steering column (not shown in
the drawings) in per se know manner. The sections of the steering column,
which are not shown in the drawings, can be formed in a conventional
manner and would not be described in detail.
The jacket tube 3 has two, downwardly projecting cheeks 6 which, e.g., are
formed integrally with the jacket tube and, as shown in FIG. 4, are
located between the legs 2 of the bracket member 1. The cheeks 6 have
elongate openings 7 which extend parallel to the steering gear shaft 4 and
at an angle to elongate openings 8 formed in the legs 2. The elongate
openings 7 form, with the respective openings 8, an of angle at least
45.degree.. The elongate openings 7 serve for adjusting the steering
column in the longitudinal direction of the steering gear shaft 4 which is
formed as a telescopic part. The elongate openings 8 serve for an
inclination or height adjustment of the steering column. In the embodiment
shown in the drawings, the pivot axis of the inclination adjustment is
formed by a bolt 9 secured on the bracket member 1 and extending through
an elongate opening 10 which is formed in the jacket tube 3 and extends
parallel to the elongate openings 7 formed in the cheeks 6 of the jacket
tube 3. However, the pivot axis of the inclination adjustment of the
steering column could also be formed by a universal joint of the steering
gear shaft itself.
A locking bolt 11 extends through the elongate openings 7, 8 which are
formed in the jacket tube 8 and/or the bracket member 1. The locking bolt
11 can be displaced to the right (in FIG. 3) with a pull device 12, with
the steering column being locked with a locking device. The pull device 12
can include a cam element fixedly connected with a clamping lever 13. The
cam element has a plurality of circumferentially arranged cams 14 which
cooperate with inclined surfaces 15 of a pressure member. Other pull
devices, e.g., those according to the state of the art described in the
introductory part of the specification, also can be used.
The locking device of the steering column includes first and second locking
members 16, 17 which cooperate with each other in the locking condition of
the locking device. As particularly shown in FIGS. 8-9, the first locking
member 16 has a body 18 with a plurality of holes 19 an inner diameter of
which is reduced at the side facing the second locking member 17, whereby
a stop shoulder is formed. Pin-shaped engaging members 20 are inserted
into the holes 19 from the side of the holes remote from the second
locking member 17. The engaging members 20 have an outwardly projecting
annular flange 21. Springs 23 are arranged between the engaging members 20
and a cover plate 22 provided on a side of the body 18 remote from the
second locking member and which is screwed to the body 18. In an unloaded
condition, the flanges 21 of the engaging members 20 abut the stop
shoulders of the respective holes 19 under the action of the springs 23,
and the engaging members 20 themselves project beyond the side of the body
18 facing the second locking member 17 by a distance d (FIG. 4). The first
locking member 16 also has a through-bore 24 through which the locking
bolt 11 extends. Further, the body 18 has, on its side facing the second
locking member 17 projections 25 provided with blind bores in which
springs 26 are received. The springs 26 are formed as helical springs.
Slide elements 27 are inserted into respective springs 26 from an end of
the springs 26 remote from the body 18.
The second locking member 17 is plate-shaped and has a plurality of rows of
receiving holes 28 and an elongate opening 29, with two rows of the
receiving holes 28 being provided on each side of the elongate opening 29.
Each row of receiving holes 28 includes a plurality of spaced from each
other holes 28 the centers of which lie on an imaginary straight line
extending parallel to the longitudinal extent of the elongate opening 29.
The engaging members 20 are associated with a respective row of receiving
holes 28. At that, a single receiving hole 28 can be associated with
several engaging members 20 and vice versa. During the adjustment of the
steering column, with the locking device being in an open position,
several receiving holes 28, which are associated with a respective
engaging member 20 are brought alternatively in a position opposite the
respective engaging member 20. The closing of the locking device is
effected in a position of the first locking member 16 in which a
respective engaging member 20 is located opposite an associated receiving
hole 28, engaging therein in the locking position of the locking device
(see FIG. 9 where respective engaging members 20 engage in respective
receiving hole 28). In case an engaging element 20 does not have an
associated receiving hole 28, it would be pressed into its hole 19 in the
body 18 against the biasing force of a respective spring 23.
When the locking device becomes closed in a position of the first locking
member 16 in which no receiving hole 28 is located opposite any of the
engaging members 20, all of the engaging members 20 are pressed into the
body 18. In case a load is applied to the steering column (during a normal
operation or in case of al crash) which would cause displacement of the
first locking member 16 relative to the second locking member 17, after a
very short displacement, a position is reached in which a respective
engaging member 20 engages in a respective receiving hole 28. With the
embodiment of the locking device shown in FIGS. 8-9, the arrangement of
eight engaging members 20 and of four rows of receiving holes 28 are so
selected that simultaneously always two engaging members 20 engage in
respective receiving holes 28.
For a steering column shown in FIGS. 1-7, the first and second locking
members 16, 17 are used for both longitudinal adjustment and inclination
adjustment. The first locking member 16 is secured, for setting the height
position of the steering column, on the locking bolt 11 on an outer side
of the leg 2 remote from the pull device 12. The locking member 16 is
secured with a nut 30 which is screwed on the locking bolt 11. The second
member 17 is secured to the outer side of the leg 2 so that the elongate
opening 29, which is formed in the locking member 17, overlaps with the
elongate opening 8 formed in the leg 2. Basically, the second locking
member 17 can be formed integrally with the leg 2 as part of the bracket
member 1. In this case, the elongate openings 29 and 8 coincide.
FIGS. 1 through 6 show an open position of the locking device. In this
position of the locking device, the ends of the engaging members 20, which
project beyond the first locking member 16 are spaced from the second
locking member 17. The projections 25 extend through the elongate opening
29 in the second locking member 17 and/or through the elongate opening 8
in the leg 2, whereby rotation of the first locking member 16 relative to
the second locking member 17 is prevented. The springs 26, together with
the slide elements 27 likewise extend through the elongate opening 29
and/or the elongate opening 8 and are supported against the outer side of
the jacket tube 3, which provides for spacing of the first locking member
16 from the second locking member 17.
Similarly, for setting the height of the steering column, a first locking
member 16 of another locking device is secured on the locking bolt 11 in
the region between the cheeks 6 of the jacket tube 3. This first locking
member 16 is supported against a shoulder of the locking bolt 11, which
prevents its displacement leftwardly (FIG. 3). The second locking member
17 of the another locking device is secured to the inner side of the cheek
6 of the jacket tube 3 which is located on the right in FIGS. 3-4. The
elongate opening 29 of the second locking member 17 of the another locking
device and through the elongate opening 7 in the cheek 6, with the slide
elements 27 being supported against the leg 2.
When from an open position of the locking device shown in FIGS. 1-6, the
clamping lever 13 is pivoted in the direction of arrow 31 (FIG. 1), the
first locking member is pulled, in views shown in FIGS. 3-4, to the right
toward the second locking member 17. The locking position of the locking
members 16 and 17, for the case of the longitudinal adjustment, is shown
in FIG. 7 in which an engaging member 20 engages in a receiving opening
28.
In the embodiment shown in the drawings, in the closed position of the
locking device, the first and second locking members 16 and 17 are pressed
against each other, whereby the two locking members become frictionally
connected with each other in addition to a formlocking connection that
results from engagement of the engaging member(s) 20 in the receiving
hole(s) 28. The frictional connection is amplified by the pressure applied
by the engaging members 20, which do not engage in the receiving holes
(28) against the outer surface of the second locking member 17.
Though frictional engagement of the first and second locking members 16 and
17 in the closed position of the locking device is preferred, it is also
contemplated and possible that the first locking member 16 would not be
pressed against the second locking member 17 in the closed position of the
locking device. Rather, the first locking member 16, in the later case,
would be spaced from the second locking member 17 by a small distance
smaller than the portion d by which the engaging member 20 projects beyond
the first locking member 16. In this case, in the closed position of the
locking device, only a reduced frictional connection is obtained, which
results from pressure applied by the engaging members 20, which are not
engaged in the holes 28, to the surface of the second locking member 17.
The fixed connection of the first second member 16 with the second locking
member 17 is insured by the formlocking connection formed as a result of
engagement of the engaging member(s) 20 in the receiving hole(s) 28.
In order to facilitate the engagement of the engaging members 20 in the
receiving holes 28, advantageously, the engaging members 20 are provided,
in the region of the free end, with bevels 32 (FIG. 8). Generally, the
engaging members 20 can have different profiles. However, advantageously,
the engaging members 20 are formed as pin-shaped members. The receiving
holes 28 can have a cross-sectional profile different from al circular
profile shown in the drawings, e.g., they can have a rectangular profile.
To compensate for the manufacturing tolerances, a corresponding play can
be provided between the engaging members 16 and the receiving holes 28. In
order to facilitate the engagement of the engaging members 20 in the
receiving holes 28 upon displacement of the first locking member 16
relative to the second locking member 17m, e.g., in the case of a crash, a
greater play can be provided between the diameters of the engaging member
20 and the receiving hole 28 in the displacement direction than in a
direction perpendicular to the displacement direction.
It is to be pointed out that different modification of the present
invention are contemplated and possible within the scope of the present
invention. Thus, the bracket member and the steering column can have a
construction different from that shown in the drawings. The possible
constructions can be those disclosed in the stand of the art discussed in
the introductory part of the specification, e.g., in addition to the
bracket member and a jacket tube, a guide member can be provided relative
to which the jacket tube can be displaced in the longitudinal direction of
the steering gear shaft and which would support the locking bolt for
displacement in the axial direction. The guide member can be arranged
between the bracket member and the jacket tube. With such a construction,
a locking bolt can be provided that would not completely extent through
the jacket tube as in the embodiment shown in the drawings but would only
project into the jacket tube.
Accordingly, though the present invention was shown and described with
references to the preferred embodiments, such are merely illustrative of
the present invention and are not to be construed as a limitation thereof
and various modifications of the present invention will be apparent to
those skilled in the art. It is therefore not intended that the present
invention be limited to the disclosed embodiments or details thereof, and
the present invention includes all variations and/or alternative
embodiments within the spirit and scope of the present invention as
defined by the append claims.
*
