# Patent

## Title
Horizontal hybrid collapsing steering column

## Abstract

The invention provides a steering column assembly having a steering column extending between a pivot end and a steering wheel supporting end. The steering wheel supporting end is operable to engage a steering wheel. The steering column is moveable along a collapse path in response to an impacting force acting on the steering wheel supporting end. The steering column includes a cam-follower surface in fixed relation to the steering wheel supporting end. The steering column assembly also includes a cam surface spaced from the steering column and slidably engaging the cam-follower surface. The cam surface and the cam-follower surface cooperate during movement of the steering column along the collapse path to guide the steering column in rotation upwardly about the pivot end.

## Background
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/567,108 for a HORIZONTAL HYBRID COLLAPSING STEERING COLUMN, filed on Apr. 30, 2004, which is hereby incorporated by reference in its entirety.


FIELD OF THE INVENTION
The invention relates to a steering column and more particularly to a steering column operable to collapse in response to an impacting force.
BACKGROUND OF THE INVENTION
Automotive steering column assemblies often include translating and/or deformable members that, in the event of a frontal collision, absorb the driver's energy, thus reducing the forces experienced by the driver. To optimize the column assembly's energy absorption performance, column manufacturers have developed two primary methods of allowing the column assembly to translate during a frontal collision. The first method is to allow the column assembly to collapse along the center line of the steering shaft, best shown in FIG. 1. A steering column assembly 10 includes first and second members 12, 14 telescopically engaged with respect to one another. The first and second members 12, 14 support a steering wheel 16. The first and second members 12, 14 telescopically collapse along the longitudinal axis of the column assembly in response to an impacting force 18 acting on the steering column 16. The steering wheel 16 moves from a first position 20 to a second position 20 (shown in phantom) in response to the impacting force 18, traveling a distance 24.
Typically, the steering shaft is at a 18-22 degree angle from horizontal. This has been the industry standard since it is easily packaged and allows for an internally collapsing column structure. Although column assemblies that collapse along the center line of the steering shaft offer certain benefits, there are disadvantages. One of the major disadvantages is that the relative position between the driver's chest and the airbag changes as the column collapses. Another disadvantage is that the collapse resistance of the column assembly is at an angle relative to the driver's input load.
The second method for allowing the column assembly to translate during a frontal collision is to allow the column assembly to horizontally translate, best shown in FIG. 2. A steering column assembly 110 includes first and second members 112, 114. The first and second members 112, 114 are slidably engaged with respect to one another and support a steering wheel 116. In response to an impacting force 118, the first member 112 and steering wheel 116 move relative to the second member 114. The steering wheel 116 moves from a first position 120 to a second position 122, traveling a distance 124. This allows the driver's input load and the column collapse resistance to be aligned. However, the major disadvantage of the horizontally collapsing column assembly is the inability to internally collapse the steering column structure. This means that the vehicle manufacturer must leave space available for the column assembly to translate during collision.
SUMMARY OF THE INVENTION
The invention provides a steering column assembly having a steering column extending between a pivot end and a steering wheel supporting end. The steering wheel supporting end is operable to engage a steering wheel. The steering column is moveable along a collapse path in response to an impacting force acting on the steering wheel supporting end. The steering column includes a cam-follower surface in fixed relation to the steering wheel supporting end. The steering column assembly also includes a cam surface spaced from the steering column and slidably engaging the cam-follower surface. The cam surface and the cam-follower surface cooperate during movement of the steering column along the collapse path to guide the steering column in rotation upwardly about the pivot end.



BRIEF DESCRIPTION OF THE DRAWINGS
Advantages of the exemplary embodiments of the invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
FIG. 1 is a steering column assembly disclosed in the prior art and collapsible along a center line of a steering shaft;
FIG. 2 is a steering column assembly disclosed in the prior art and operable to horizontally translate in response to a frontal collision, wherein the steering column assembly is shown prior to the frontal collision;
FIG. 3 is the steering column assembly shown in FIG. 2 after the frontal collision;
FIG. 4 is a schematic view of a steering column assembly according to a first exemplary embodiment of the invention before a frontal collision according to the exemplary embodiment of the invention;
FIG. 5 is the steering column assembly shown in FIG. 4 after the frontal collision;
FIG. 6 is a graph illustrating the relationship between vertical displacement of a rake bolt and angular rotation of the steering column assembly about a lower bracket during telescopic collapse of the exemplary steering column assembly;
FIG. 7 is a graph illustrating the relationship between the vertical displacement of the rake bolt and horizontal displacement of the rake bolt during telescopic collapse of the exemplary steering column assembly;
FIG. 8 is a graph illustrating the relationship between the vertical displacement of the rake bolt and horizontal displacement of a steering wheel during telescopic collapse of the exemplary steering column assembly;
FIG. 9 is a schematic view of a guide according to a second exemplary embodiment of the invention;
FIG. 10 is a schematic view of a steering column assembly according to a third exemplary embodiment of the invention before a frontal collision according to the exemplary embodiment of the invention; and
FIG. 11 a schematic view of a steering column assembly according to a fourth exemplary embodiment of the invention before a frontal collision according to the exemplary embodiment of the invention shown in solid line and shown after a frontal collision in phantom.



DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A plurality of different embodiments of the invention are shown in the Figures of the application. Similar features are shown in the various embodiments of the invention. Similar features have been numbered with a common two-digit reference numeral and have been differentiated by a third digit placed before the two common digits. Also, to enhance consistency, features in any particular drawing share the same third digit designation even if the feature is shown in less than all embodiments. Similar features are structured similarly, operate similarly, and/or have the same function unless otherwise indicated by the drawings or this specification. Furthermore, particular features of one embodiment can replace corresponding features in another embodiment unless otherwise indicated by the drawings or this specification.
Referring now to FIGS. 4 and 5, in a first exemplary embodiment of the invention, a steering column assembly 26 includes a steering column 74 with first and second members 28, 30 telescopically engaged with one another. The first member 28 defines a steering wheel supporting end 32 for supporting a steering wheel 34. The second member 30 defines a pivot end 76 with a pivot point 36. The steering column assembly 26 defines an axis 38 rotatable about the pivot point 36. The steering column assembly 26 telescopically collapses along the axis 38 in response to an impacting force 64 acting on the steering wheel 34. The axis 38 defines a collapse path.
The invention also includes a guide 40 for guiding movement of the steering column assembly 26 during telescopic collapse. The guide 40 guides the steering column assembly 26 in rotation upwardly about the pivot point 36 in response to telescopic collapse along the axis 38. In the first exemplary embodiment of the invention, the guide 40 is attachable to the vehicle and defines a slot 42, the slot 42 defining a cam surface 80. The first member includes a second portion 44 that is received in the slot 42. The second portion 44 can be pin-like and fixedly associated with the first member 28 and defines a cam-follower surface 78. In alternative embodiments of the invention, the guide 40 could define a single cam surface that guides movement of the first member 28 during telescopic collapse rather than a closed slot.
In FIGS. 4 and 5 of the exemplary embodiment, the slot 42 appears straight and the invention can be practiced with a perfectly straight slot 42. However, in the preferred embodiment of the invention, slot 42 is arcuate. In FIG. 9, in a second exemplary embodiment of the invention, a guide 140 is shown in exaggerated form, having an arcuate slot 142. The shape of slot 142 can be selected based on the operating environment of the steering column assembly 26 to enhance the likelihood that the path of travel of the steering column assembly is aligned with the impact force. It can be desirable to guide the steering wheel supporting end 32 along an arcuate path of movement or a straight path of movement. For example, when the driver is wearing a seat belt during an impact situation, the path of movement for the driver may define an arc about the seat belt. In other vehicles, the path of movement for the driver may define an arc over a first distance of movement and be substantially straight over a second distance of movement. The guide slot 142 can be designed in response to the expected path of movement for the driver in an impact situation and the expected path may be different in different operating environments.
In reference to FIG. 5 and charts 1 and 2 provided immediately below, data corresponding to the shape of the exemplary slot 42 is provided. In chart 1, the value A represents the distance in millimeters between the pivot point 36 and the second portion 44 prior to an impacting force acting on the steering wheel 34. The value B represents the vertical distance in millimeters between a horizontal plane 46 and a horizontal plane 48. The pivot point 36 is disposed in the horizontal plane 46 and the steering wheel supporting end 32 is disposed in the horizontal plane 48. The value C represents the horizontal distance in millimeters between the pivot point 36 and the steering wheel supporting end 32. The value D represents the distance in millimeters between the second portion 44 and the steering wheel supporting end 32 along the axis 38. In chart 2, the value X represents an arbitrary change in position of the steering column assembly 26. Theta (rad) and Theta 1 (deg) correspond to one another and represent the angle between the axis 38 and the horizontal plane 48. Theta 2 (deg) represents the angle between the horizontal plane 46 and the axis 38. The value Z represents the horizontal distance of travel in millimeters by the second portion 44 from a starting position in the direction of the pivot point 36. The value V represents the vertical distance of travel in millimeters by the second portion 44 from a starting point in the direction of the pivot point 36. The value Y represents the amount of telescopic collapse in millimeters of the first and second members 28, 30 relative to one another.










TABLE 1









A
300



B
150



C
370.81



D
100























TABLE 2






Theta
Theta1
Theta2





X
(rad)
(deg)
(deg)
Z
V
Y





















0
0.384
22.026
67.974
0.000
0.000
0.000


1
0.385
22.080
67.920
0.965
0.087
0.927


2
0.386
22.134
67.866
1.929
0.175
1.853


3
0.387
22.188
67.812
2.893
0.262
2.779


4
0.388
22.243
67.757
3.857
0.351
3.705


5
0.389
22.298
67.702
4.821
0.439
4.631


6
0.390
22.353
67.647
5.785
0.528
5.556


7
0.391
22.408
67.592
6.748
0.618
6.480


8
0.392
22.464
67.536
7.711
0.707
7.405


9
0.393
22.520
67.480
8.673
0.797
8.329


10
0.394
22.576
67.424
9.636
0.888
9.252


11
0.395
22.632
67.368
10.598
0.979
10.175


12
0.396
22.689
67.311
11.560
1.070
11.098


13
0.397
22.746
67.254
12.521
1.162
12.021


14
0.398
22.803
67.197
13.483
1.254
12.943


15
0.399
22.861
67.139
14.444
1.346
13.864


16
0.400
22.918
67.082
15.405
1.439
14.786


17
0.401
22.977
67.023
16.365
1.533
15.707


18
0.402
23.035
66.965
17.325
1.626
16.627


19
0.403
23.093
66.907
18.285
1.721
17.547


20
0.404
23.152
66.848
19.245
1.815
18.467


21
0.405
23.212
66.788
20.204
1.910
19.386


22
0.406
23.271
66.729
21.163
2.005
20.305


23
0.407
23.331
66.669
22.122
2.101
21.223


24
0.408
23.391
66.609
23.081
2.197
22.141


25
0.409
23.451
66.549
24.039
2.294
23.059


26
0.410
23.512
66.488
24.996
2.391
23.976


27
0.411
23.573
66.427
25.954
2.489
24.893


28
0.412
23.634
66.366
26.911
2.587
25.809


29
0.414
23.696
66.304
27.868
2.685
26.725


30
0.415
23.757
66.243
28.825
2.784
27.641


31
0.416
23.820
66.180
29.781
2.883
28.556


32
0.417
23.882
66.118
30.737
2.983
29.470


33
0.418
23.945
66.055
31.692
3.083
30.385


34
0.419
24.008
65.992
32.648
3.183
31.298


35
0.420
24.071
65.929
33.603
3.284
32.212


36
0.421
24.135
65.865
34.557
3.386
33.124


37
0.422
24.199
65.801
35.512
3.488
34.037


38
0.423
24.263
65.737
36.466
3.590
34.949


39
0.425
24.328
65.672
37.419
3.693
35.860


40
0.426
24.393
65.607
38.372
3.796
36.771


41
0.427
24.458
65.542
39.325
3.900
37.682


42
0.428
24.524
65.476
40.278
4.004
38.592


43
0.429
24.590
65.410
41.230
4.109
39.501


44
0.430
24.656
65.344
42.182
4.214
40.410


45
0.431
24.723
65.277
43.133
4.320
41.319


46
0.433
24.790
65.210
44.084
4.426
42.227


47
0.434
24.857
65.143
45.035
4.533
43.135


48
0.435
24.925
65.075
45.985
4.640
44.042


49
0.436
24.993
65.007
46.935
4.747
44.948


50
0.437
25.061
64.939
47.885
4.855
45.855


51
0.439
25.130
64.870
48.834
4.964
46.760


52
0.440
25.199
64.801
49.782
5.073
47.665


53
0.441
25.268
64.732
50.731
5.183
48.570


54
0.442
25.338
64.662
51.679
5.293
49.474


55
0.443
25.408
64.592
52.626
5.403
50.377


56
0.445
25.479
64.521
53.573
5.515
51.281


57
0.446
25.550
64.450
54.520
5.626
52.183


58
0.447
25.621
64.379
55.467
5.738
53.085


59
0.448
25.692
64.308
56.412
5.851
53.986


60
0.450
25.764
64.236
57.358
5.964
54.887


61
0.451
25.837
64.163
58.303
6.078
55.788


62
0.452
25.909
64.091
59.248
6.192
56.687


63
0.453
25.983
64.017
60.192
6.307
57.587


64
0.455
26.056
63.944
61.135
6.422
58.485


65
0.456
26.130
63.870
62.079
6.538
59.383


66
0.457
26.204
63.796
63.022
6.654
60.281


67
0.459
26.279
63.721
63.964
6.771
61.178


68
0.460
26.354
63.646
64.906
6.888
62.074


69
0.461
26.429
63.571
65.847
7.006
62.970


70
0.463
26.505
63.495
66.788
7.125
63.865


71
0.464
26.582
63.418
67.729
7.244
64.760


72
0.465
26.658
63.342
68.669
7.364
65.654


73
0.467
26.735
63.265
69.608
7.484
66.547


74
0.468
26.813
63.187
70.548
7.605
67.440


75
0.469
26.891
63.109
71.486
7.726
68.332


76
0.471
26.969
63.031
72.424
7.848
69.224


77
0.472
27.048
62.952
73.362
7.970
70.115


78
0.473
27.127
62.873
74.299
8.093
71.005


79
0.475
27.207
62.793
75.235
8.217
71.895


80
0.476
27.287
62.713
76.171
8.341
72.784


81
0.478
27.367
62.633
77.107
8.466
73.672


82
0.479
27.448
62.552
78.042
8.591
74.560


83
0.480
27.530
62.470
78.976
8.717
75.447


84
0.482
27.611
62.389
79.910
8.844
76.334


85
0.483
27.694
62.306
80.844
8.971
77.219


86
0.485
27.776
62.224
81.777
9.099
78.105


87
0.486
27.860
62.140
82.709
9.227
78.989


88
0.488
27.943
62.057
83.640
9.356
79.873


89
0.489
28.027
61.973
84.572
9.486
80.756


90
0.491
28.112
61.888
85.502
9.616
81.638


91
0.492
28.197
61.803
86.432
9.747
82.520


92
0.494
28.282
61.718
87.362
9.879
83.401


93
0.495
28.368
61.632
88.290
10.011
84.281


94
0.497
28.455
61.545
89.219
10.143
85.161


95
0.498
28.542
61.458
90.146
10.277
86.040


96
0.500
28.629
61.371
91.073
10.411
86.918


97
0.501
28.717
61.283
92.000
10.545
87.795


98
0.503
28.806
61.194
92.925
10.681
88.672


99
0.504
28.895
61.105
93.850
10.817
89.548


100
0.506
28.984
61.016
94.775
10.953
90.423









In addition to the tables provided above, FIGS. 6-8 provide charts detailing exemplary dimensional data. In FIG. 6, the graph plots the horizontal displacement of the second portion 44 or rake bolt in millimeters along the Y axis and the angular rotation of the steering column assembly 26 about the pivot point 36 or lower bracket in millimeters along the X axis. The line 50 is a straight reference line and the line 52 represents the exemplary dimensional data. FIG. 6 illustrates that a rate of horizontal displacement of the second portion 44 decreases as the angle between the horizontal plane 46 and the axis 38 increases. FIG. 7 illustrates the movement of the second portion 44 in a vertical direction relative to the movement of the second portion 44 in the horizontal direction. The line 54 is a straight reference line and the line 56 represents the exemplary dimensional data. FIG. 8 illustrates the relationship between the movement of the second portion 44 and the vertical direction and the movement of the steering wheel supporting end 32 in the horizontal direction. The line 58 is a straight reference line and the line 60 represents exemplary dimensional data. The data in the tables and the charts demonstrates that the steering wheel supporting end 32 moves substantially along the horizontal plane 48 as the steering column assembly 26 rotates about the pivot point 36, whereby the vertical distance traveled, shown as delta d, by steering wheel 34 is minimized.
Referring now to FIGS. 4 and 5, in operation, the steering wheel supporting end 32 and associated steering wheel 34 are disposed at a first position 62 prior to the impacting force 64 being directed to the steering wheel 34. In response to the impacting force 64, the first and second members 28, 30 telescopically collapse with respect to one another and the steering column assembly 26 rotates about the pivot point 36 in the angular direction 66. The first member 28 is guided in movement by the cooperation between the second portion 44 and the slot 42. The first member 28 is also guided in movement by being telescopically engaged with the second member 30. During movement of the steering column assembly 26, the steering wheel supporting end 32 moves substantially horizontal along a second path 82, such as along the horizontal plane 48. As a result, the impacting force 44 and the path of travel of the steering wheel 34 are substantially aligned. The steering wheel supporting end 32 moves along the horizontal plane 48 from the first position 62 to a second position 68 in response to the impacting force 64.
In alternative embodiments of the invention, a position along the axis 38 further from pivot point 36 than the steering wheel supporting end 32 may move along a horizontal path and the steering wheel supporting end 32 may move along a path that is at an angle to the horizontal plane 48. For example, it can be desirable to move an air bag, or inflatable restraint, associated with the steering wheel along a horizontal path. The inflatable restraint would be disposed at a position along the axis 38 further from pivot point 36 than the steering wheel supporting end 32. As used in the application relative to the first exemplary embodiment of the invention, the steering wheel supporting end is the position along the axis 38 that is desired to move in a horizontal plane. In the third exemplary embodiment of the invention discussed below, the steering wheel supporting end is moved along a path that is at an angle to the horizontal plane and a inflatable restraint is moved along a horizontal path.
The invention can also include a knee bolster 70 associated with the first member 28. The knee bolster 70 moves with the first member 28 along a horizontal third path 84 in response to the impacting force 64. Also, an energy absorbing (“E/A”) device 72 may be coupled to the steering column assembly 26, as schematically shown in FIGS. 4 and 5, which is operative in response to the collapse to absorb all or part of the energy of impact to dissipate the energy in a controlled manner. Any E/A device suitable for usage with a collapsing first and second steering column members 28, 30 could be used and is contemplated with the scope of the present invention. The knee bolster 70 could employ the same or different E/A device as that of device 72.
Referring now to FIG. 10, in a third exemplary embodiment of the invention, a steering column assembly 226 having a steering column 274 extending between a pivot end 276 and a steering wheel supporting end 232. The steering wheel supporting end 232 is operable to engage a steering wheel 234. The steering column 274 is moveable along a collapse path in response to an impacting force 264 acting on the steering wheel supporting end 232. The steering column 274 includes a cam-follower surface 278 in fixed relation to the steering wheel supporting end 232. The steering column assembly 226 also includes a cam surface 280 spaced from the steering column 274 and slidably engaging the cam-follower surface 278. The cam surface 280 and the cam-follower surface 278 cooperate during movement of the steering column 274 along the collapse path to guide the steering column 274 in rotation upwardly about the pivot end 276.
The cam surface 280 is a rake bolt 244. The cam-follower surface 278 is a first arcuate slot 242 receiving the rake bolt 244. The cam surface 280 and the cam-follower surface 278 cooperate during movement of the steering column 274 along the collapse path to move the steering wheel supporting end 232 along a second path 282 extending substantially parallel to the impacting force 264.
The steering column assembly 226 is adjustable in raking movement 292. A rake bracket 286 (shown in phantom) having a second arcuate slot 288 receives the rake bolt 244. The rake bolt 244 and the second arcuate slot 288 cooperate to guide the steering column 274 in raking adjustment and are fixed relative to one another during movement of the steering column 274 along the collapse path. The steering column assembly 226 can also include a locking mechanism to selectively lock the steering column 274 relative to the rake bracket 286, such as shown in U.S. Pat. Nos. 6,616,185 and 6,659,504, which are hereby incorporated by reference.
Referring now to FIG. 11, in a fourth exemplary embodiment of the invention, a steering column assembly 326 having a steering column 374 extending between a pivot end 376 and a steering wheel supporting end 332. The steering wheel supporting end 332 is operable to engage a steering wheel (not shown). The steering column 374 is moveable along a collapse path in response to an impacting force 364 acting on the steering wheel supporting end 332. The steering column 374 includes a cam-follower surface 378 in fixed relation to the steering wheel supporting end 332. The steering column assembly 326 also includes a cam surface 380 spaced from the steering column 374 and slidably engaging the cam-follower surface 378. The cam surface 380 and the cam-follower surface 378 cooperate during movement of the steering column 374 along the collapse path to guide the steering column 374 in rotation upwardly about the pivot end 376.
The cam surface 380 is a an instrument panel support structure 390 sloping downwardly along the collapse path toward the pivot end 376. The cam-follower surface 278 is defined by a rake bracket 386. The rake bracket 386 selectively fixedly engageable with the steering column 374. The cam surface 380 and the cam-follower surface 378 cooperate during movement of the steering column 374 along the collapse path to move the steering wheel supporting end 332 along a second path 382 extending substantially parallel to the impacting force 364. In alternative embodiments of the invention, the cam surface 380 could be defined by any structure that is fixed relative to the vehicle while the rake bracket 386 moves during telescopic collapse of the steering column assembly 326. For example, the cam surface 380 could be defined by a bracket fixed to the steering column assembly 326 during normal vehicle handling and fixed to the vehicle during normal vehicle handling and during an impact situation.
The steering column assembly 326 is adjustable in raking movement 392 and adjustable in telescoping movement 394. The steering column assembly 326 can also include a locking mechanism to selectively lock the steering column 274 relative to the rake bracket 286, such as shown in U.S. Pat. Nos. 6,616,185 and 6,659,504, which are hereby incorporated by reference. FIG. 11 also shows a fourth path 396 of movement of a centerline of an inflatable restraint (not shown). The impacting force 364 is spaced from the steering wheel supporting end 332, striking the inflatable restraint. A first position 98 along the path 396 corresponds to the position of the inflatable restraint prior to application of the impacting force 364. A second position 100 along the path 396 corresponds to the position of the inflatable restraint subsequent to application of the impacting force 364.
The exemplary embodiments of the invention offer a safety and packaging improvement over the prior art. The exemplary embodiments includes a column assembly that translates generally horizontally along a collapse path different than that of the longitudinal axis of the column assembly and also internally collapses. This allows the relative position of the airbag to be maintained, as well as allows the driver's input force and the column collapse resistance to be more closely aligned in the same plane. Also, the invention allows the column assembly to be more easily packaged. In the exemplary embodiments of the invention, a column assembly rotates about a lower mounting bracket as it internally collapses. The collapse of the column assembly is guided such that as the column collapses the center line of the airbag remains in the same generally horizontal plane. Another advantage of the exemplary embodiments is that the column assembly is prevented from dropping and injuring the driver after the application of the impacting force. The column assembly according to the invention may advantageously be used in combination with any suitable energy absorbing device to manage the dissipation of energy through controlled collapse of the column. In other operating environments and in other forms, the invention can provided different and/or additional advantages.
While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.

## Claims

1. A steering column assembly comprising:
a steering column extending along an axis and including a first member having a steering wheel supporting end operable to engage a steering wheel and a second member telescopically engaged with said first member and having a pivot end defining a pivot point about which said steering column is rotatable, wherein said first member is telescopically moveable along a first predetermined collapse path relative to said second member in response to an impacting force acting on said steering wheel supporting end, and wherein said first predetermined collapse path is collinear with said axis;
said steering column including a cam follower surface in fixed relation to said steering wheel supporting end; and
a cam surface defining a guide slot that is spaced from said steering column and slidably engaging said cam-follower surface to define a second predetermined collapse path of said steering column in continuous fixed relation to said first predetermined collapse path, wherein said guide slot and said cam-follower surface cooperate during said telescopic movement of said steering column along said first predetermined collapse path to guide said first member and said second member of said steering column in rotation upwardly about said pivot point and to guide said steering wheel supporting end along said second predetermined collapse path.

2. The steering column assembly of claim 1, wherein said steering column has an angle θ1 relative to a horizontal plane between the range of 22 degrees and 29 degrees and said guide slot is angled relative to said horizontal plane.

3. The steering column assembly of claim 1, wherein said cam surface and said cam-follower surface are further defined as cooperating during movement of said steering column along said first collapse path to move said steering wheel supporting end along said second collapse path extending in a substantially horizontal plane.

4. The steering column assembly of claim 1, wherein said cam surface and said cam-follower surface are further defined as cooperating during movement of said steering column along said first collapse path to simultaneously move said steering wheel supporting end along said second collapse path.

5. The steering column assembly of claim 1, wherein said cam surface and said cam-follower surface are further defined as cooperating during movement of said steering column along said first collapse path to move said steering wheel supporting end along said second collapse path extending substantially parallel to the impacting force.

6. The steering column assembly of claim 5, wherein a substantially horizontal distance between said pivot end and said steering wheel supporting end decreases during movement of said steering column along said first collapse path and a substantially vertical distance between said pivot end and said steering wheel supporting end is substantially constant during movement of said steering wheel supporting end along said second collapse path.

7. The steering column assembly of claim 5, further comprising: a knee bolster fixedly engaged with said steering column and moveable along a third collapse path extending substantially parallel to the impacting force during movement of said steering column along said first collapse path.

8. The steering column assembly of claim 1, where said guide slot is arcuate.

9. A steering column assembly comprising:
a steering column including a first member having a steering wheel supporting end operable to engage a steering wheel and a second member telescopically engaged with said first member, said first member is telescopically moveable along a first collapse path relative to said second member in response to an impacting force acting on said steering wheel supporting end;
said steering column including a cam-follower surface fixed to said steering wheel supporting end; and
a cam surface defining a guide slot that is spaced from said steering column and slidably engaging said cam-follower surface to define a second collapse path of said steering column in continuous fixed relation to said first collapse path, said guide slot and said cam-follower surface cooperate during said telescopic movement of said steering column along said first collapse path to simultaneously guide said steering wheel supporting end along said second collapse path.

10. A steering column assembly comprising:
a steering column including a first member having a steering wheel supporting end operable to engage a steering wheel and a second member telescopically engaged with said first member, said first member being telescopically moveable along a predefined first collapse path relative to said second member in response to an impacting force acting on said steering wheel supporting end;
said steering column including a cam-follower surface fixed to said steering wheel supporting end; and
a cam surface defining a guide slot that is spaced from said steering column and slidably engaging said cam-follower surface to define a second collapse path of said steering column having a continuous predefined fixed relation to said first collapse path, said guide slot and said cam-follower surface cooperate during said telescopic movement of said steering column along said first collapse path to simultaneously guide said steering wheel supporting end along said second collapse path, and wherein said steering column has an angle θ, relative to a horizontal plane greater than 22 degrees and said guide slot is angled relative to said horizontal plane.