Steering column support bracket

A steering column support bracket for a vehicle that is attached to HVAC ducts extending transversely across the vehicle that are located between the dashboard and the front of dashboard cowl. The steering column support bracket is attached to the hinge pillar, the front of dashboard cowl and is connected by a brace to the compartment pan of the vehicle. Several embodiments of steering column support brackets are disclosed that are designed to engage the HVAC ducts. The steering column support bracket may be formed as a C-shaped structure, an under duct configuration, or in a clam shell structure. In addition to supporting the steering column of the vehicle, the steering column support bracket may support brake switches, a power steering motor, and a cruise control system.

TECHNICAL FIELD
 The present invention relates to a steering column support bracket for a
 vehicle.
 BACKGROUND ART
 The dashboard portion of a vehicle is a complex multifunction assembly that
 presents considerable challenges for a vehicle design. Systems that are
 incorporated into the dashboard include the instrument panel, heating
 ventilation and air conditioning (HVAC) ducts, stereo systems, power
 steering systems, cruise control systems, and vehicle system wiring. All
 of these systems and components must be housed within the dashboard behind
 the instrument panel in a compact and attractive package. To maximize
 vehicle interior space, the amount of space available to house all of the
 components and systems of a vehicle dashboard must be minimized.
 Pressure to improve fuel economy translates into a need to reduce the
 weight of vehicles. The dashboard of a vehicle is one of the areas that
 can be focused on for weight savings and could ultimately lead to improved
 fuel economy. Conventional dashboards have included a steel cross-car
 support that extends transversely across the car. It has been proposed to
 eliminate the steel cross-car support and provide instead structural HVAC
 ducts that support and reinforce the car body. One problem presented by
 this approach is that it is necessary to support the steering column that
 may weigh as much as 30 lbs. Another problem is the need to limit
 vibration frequencies in the column to 35 hertz. Steering columns must
 also be designed to meet FMVSS 201 and FMVSS 208 standards as well as OBD
 and DSI requirements.
 Generally, the space enclosed by the dashboard between the instrument panel
 and the front of the dashboard cowl is relatively limited especially in
 view of the large number of vehicle components and systems that are housed
 within the dashboard. HVAC ducts, instrument panel wiring harnesses, audio
 systems, air bag systems, break pedal sleds, brake switches, power
 steering components, cruise control and other systems are preferably
 housed within the dashboard. In addition, a tilt steering wheel
 necessitates accommodating a steering column tilt joint and clearance for
 adjustment of the steering column tilt angle. All of these components must
 be securely retained within the dashboard so that parts do not vibrate or
 rattle beneath the dashboard.
 One problem encountered by the prior art is the amount of clearance
 required for brake pedals, brake pedal sleds and brake switches.
 Automotive manufacturers require a "big foot" zone around the brake pedal
 that assures the ample clearance regardless of the size of a driver's
 foot. When brake switches are provided on the brake sled a large hole is
 required in the sound dampening panel or "hush panel" that can adversely
 affect the effectiveness of the sound dampening panel.
 Finally, it is important that any vehicle system or subsystem such as a
 steering column support bracket be easily manufactured and assembled
 during the vehicle assembly process. Access must be provided for welding
 components together or securing components with fasteners. It is also
 important to save tooling expense and reduce operation cycle times to keep
 costs to a minimum while meeting all applicable standards and
 requirements.
 The above problems and challenges are addressed by the Applicant's
 invention as summarized below.
 DISCLOSURE OF INVENTION
 The present invention relates to a steering column support bracket for a
 vehicle. The vehicle has a steering column, a dashboard, a cowl located in
 front of the dashboard, and HVAC ducts extending transversely across the
 vehicle between the dashboard and the cowl. The steering column support
 bracket is attached to the cowl, a hinge pillar; and a compartment pan of
 the vehicle. The steering column support bracket is preferably formed as
 an integral body comprising a bottom wall, a rear wall contiguous with and
 extending upwardly from the bottom wall, and a top wall that is contiguous
 with and extends forward to the rear wall. The bottom wall, rear wall, and
 top wall are assembled around the HVAC ducts. A hinge pillar bracket is
 formed on one lateral end of the steering column support bracket and is
 attached to the hinge pillar. A front of dashboard cowl bracket is formed
 on the forward edge of the top wall that is adapted to be attached to the
 cowl. A brace is connected to the other lateral end (relative to the
 lateral end on which the hinge pillar bracket is formed) of the steering
 column support bracket and to the compartment pan of the vehicle.
 Several alternative embodiments are disclosed of the steering column
 support bracket for a vehicle having components as described above that
 cooperate with the steering column support bracket. One alternative
 embodiment, includes a bottom wall and a front wall that extends upwardly
 from the bottom wall to the front of dashboard cowl. The bottom wall and
 front wall are assembled to multi-part HVAC ducts after they are fully
 assembled and is connected to the hinge pillar, front of dashboard cowl,
 and brace as described.
 According to another alternative embodiment the invention, a steering
 column support bracket is provided for a vehicle having the same
 components described above that function with the steering column support
 bracket. Another alternative embodiment includes a lower clam shell panel
 and an upper clam shell panel that are assembled around the HVAC ducts.
 The steering column support bracket is connected to the hinge pillar, the
 dashboard cowl and brace as previously described.
 According to other aspects of the present invention, the steering column
 support bracket is adapted to have the brake pedal and brake switches
 attached thereto as well as other components such as the power steering
 motor and cruise control module. In the clam shell embodiment, the upper
 and lower clam shell panels are secured together by fasteners. The clam
 shell panels may also be provided with interlocking elements in addition
 to fasteners to allow interlocking connection of the upper and lower clam
 shell panels on one edge while other portions of the clam shell panels are
 secured together by fasteners.

BEST MODE FOR CARRYING OUT THE INVENTION
 Referring now to FIG. 1, a molded plastic cross-car beam 10 is shown to be
 comprised of a first panel 12, a second panel 14, and a third panel 16.
 The cross-car beam 10 defines heating, ventilation and air conditioning
 (HVAC) ducting within the dashboard of a vehicle. The cross-car beam 10 is
 a structural plastic member formed by a series of layers to provide a
 cross-car beam that can replace a steel cross-car beam that was formerly
 provided as part of the dashboard of a vehicle.
 One embodiment of a steering column support bracket 18 is shown in FIG. 1.
 The first panel 12 and second panel 14 are assembled together prior to
 assembly of the steering column support bracket 18. The steering column
 support bracket 18 has a generally C-shaped configuration and is received
 around three sides of the assembled first and second panels 12, 14. A
 brake sled 20 is adapted to be assembled to the steering column support
 bracket 18 either before or after assembly of the third panel 16 over the
 steering column support bracket 18.
 As shown in FIG. 1, a defroster duct 24 is ported to the first panel 12 for
 directing heated air from the HVAC ducts to impinge upon the windshield
 (not shown). A plurality of knee crush brackets 26 are provided to support
 the lower portion of the third panel 16. A pencil brace 28 is provided to
 connect the steering column support bracket 18 to the tunnel bracket 30 or
 tunnel 32 of the vehicle compartment pan 34.
 A hinge pillar 38 of a vehicle is partially shown in FIG. 1. A hinge pillar
 bracket 40 is formed on one end of the steering column support bracket 18
 and is fastened to the hinge pillar 38. A cowl bracket 42 extends
 forwardly from the steering column support bracket 18 and is adapted to be
 secured to the front of dash cowl 46, as shown in FIG. 2. The front of
 dash cowl 46 corresponds to what was formerly referred to as the firewall
 of the vehicle. The steering column support bracket 18 is supported by
 means of the pencil brace 28, hinge pillar bracket 40, and cowl bracket 42
 in such a way that it minimizes vibration and provides a durable
 high-strength support for the steering column of the vehicle.
 Referring now to FIG. 2, the construction of the steering column support
 bracket 18 is shown and its relationship to the first and second panels
 12, 14 of the cross-car beam 10 and the front of dash cowl 46 is
 illustrated schematically. The steering column support bracket 18 includes
 a bottom wall 50, a rear wall 52, and a top wall 54. Note, as used herein,
 the terms "front" and "rear" refer to the directions corresponding to the
 front and rear of the vehicle. The bottom wall 50, rear wall 52, and top
 wall 54 partially encircle the first and second panels 12, 14. The
 steering column support bracket 18 is preferably formed as a molded
 magnesium part for high strength and ridigity. However, it is possible
 that the steering column support bracket 18 could be formed of a
 fiber-reinforced molded plastic material.
 Referring now to FIG. 3, the steering column support bracket 18 is shown
 from the point of view of the front of dash cowl 46, that is, from the
 front of the vehicle looking rearwardly from inside the dashboard. A
 steering column 58 is partially shown. A brake pedal 60 is pivotably
 secured to the brake pedal pivot arm 62. Brake switches 64 are provided
 adjacent to the top of the pedal 60 so that when the pedal 60 pivots on
 the brake pedal pivot arm 62, the brake switch 64 may be actuated. A
 cruise control module 68 is shown to be secured to the lower portion of
 the steering column support bracket 18. In addition, an electronic power
 steering motor (not shown) could also be secured to the steering column
 58. It will be readily appreciated that the addition of the cruise control
 module 68 and electronic power steering motor in addition to the steering
 column substantially increases the weight that must be supported by the
 steering column support bracket 18. Since these relatively heavy modules
 and components are supported by the steering column support bracket 18,
 less weight must be carried by the cross-car beam 10. By locating the
 brake pedal switches on the steering column support bracket 18 adjacent
 the top of the pedal 60, it is possible to eliminate some of the material
 of the brake pedal sled of the prior art. This should result in additional
 weight reduction.
 Referring now to FIG. 4, assembly of the steering column support bracket 18
 is illustrated wherein the first panel 12 and second panel 14 are
 initially assembled together to form part of the cross-car beam 10. The
 steering column support bracket 18 is then assembled to the first and
 second panels 12, 14 with the hinge pillar bracket 40 and cowl bracket 42
 extending beyond the cross-car beam 10 to be secured to the hinge pillar
 38 and front of dash cowl 46, respectively. The third panel 16 is then
 assembled over the steering column support bracket 18 and the first and
 second panels 12, 14.
 Referring now to FIG. 5, an alternative embodiment of the present invention
 is shown that is referred to as the under duct mount steering column
 support bracket 70. The under duct mount steering column support bracket
 70 includes a bottom wall 72 and a forward wall 74. A cowl bracket 76
 extends forwardly of the forward wall 74 for attachment to the front of
 dash cowl 46.
 Referring to FIG. 6, the arrangement of the under duct mount alternative is
 shown wherein the cross-car beam 10 including the first, second, and third
 panels 12, 14, and 16 are initially secured together. The under duct mount
 steering column support bracket 70 may then be assembled to the cross-car
 beam 10 from below and secured to the front of dash cowl 46 by means of
 the cowl bracket 76. An advantage of this alternative is that the
 cross-car beam 10 may be fully assembled and welded together as a unitary
 piece before the steering column support bracket 70 is assembled as part
 of the dashboard to the front of dash cowl 46. The under duct mount
 steering column support bracket 70 is preferably formed of molded
 magnesium but may also be manufactured from other structural fiber
 reinforced plastic materials as discussed above with reference to the
 steering column support bracket 18. Alternatively, this embodiment could
 be formed of sheet molding compound (SMC), if desired.
 Referring now to FIGS. 7 and 8, another embodiment of the present invention
 referred to as the clam shell embodiment is shown schematically. An upper
 clam shell 80 and lower clam shell 82 each include threaded openings 84 in
 which bolts 86 are received to secure the upper and lower clam shells 80,
 82 together. While the threaded openings 84 and bolts 86 are shown on only
 one flange of the upper and lower clam shell 80, 82, other fasteners could
 be used to secure the panels together or an interlocking flange could be
 used to hold one or more flanges of the upper clam shell 80 and lower clam
 shell 82 together. When assembled as shown in FIG. 8, the cross-car beam
 10 is received within the opening defined by the upper clam shell 80 and
 lower clam shell 82. The clam shell could be manufactured from
 polypropylene reinforced with fiberglass or another appropriate structural
 polymer material.
 While embodiments of the invention have been illustrated and described, it
 is not intended that these embodiments illustrate and describe all
 possible forms of the invention. Rather, the words used in the
 specification are words of description rather than limitation, and it is
 understood that various changes may be made without departing from the
 spirit and scope of the invention.