Vehicle structural air duct

A vehicle body structure includes spaced roof rails and a structural air duct. The air duct has at least two bows connecting between the roof rails and defining first and second channels. An interconnecting member is connected between the bows and defines a third channel connecting the first and second channels in fluid communication with each other. At least one of the bows defines an outlet port configured to supply air to a cabin.

TECHNICAL FIELD

The present disclosure relates to a heating, ventilation, and air conditioning (HVAC) system having a structural air duct integrated into a roof structure of a vehicle.

BACKGROUND

Automotive vehicles include HVAC systems for heating and cooling the passenger cabin of the vehicle. Larger sport-utility vehicles (SUV) typically include an overhead air duct disposed above the second and third rows of seats. The air ducts are not part of the roof structure and are typically located under the cross members of the roof structure and above the headliner. The air ducts include outlet ports that supply air into the passenger cabin.

SUMMARY

According to one embodiment, a vehicle body structure includes spaced roof rails and a structural air duct. The air duct has at least two bows connecting between the roof rails and defining first and second channels. An interconnecting member is connected between the bows and defines a third channel connecting the first and second channels in fluid communication with each other. At least one of the bows defines an outlet port configured to supply air to a cabin.

According to another embodiment, a vehicle includes roof rails, a rear header extending between the rails, and a structural air duct located forward of the rear header. The air duct has a structural body defining an open channel and having first and second portions each connected to one of the rails. A component is sealed to flanges of the body and covers over the body to define a plenum.

According to yet another embodiment, a vehicle includes roof rails and a structural air duct having a structural body with at least four mounting portions each attached to one of the roof rails. An outlet port is defined in a bottom of the body. An air shutter is disposed in the outlet port. A component is sealed to a top of the body such that the body and the component cooperate to define a plenum.

DETAILED DESCRIPTION

Referring toFIGS. 1 and 2, a vehicle20, such as an SUV, has a pair of longitudinal body sides22formed on opposing sides of the vehicle. A pair of spaced apart roof rails24extend longitudinally along the vehicle and are located at an upper portion of the body sides22. The body structure includes pillars such as A-pillars25, B-pillars26, C-pillars27, and D-pillars28that extend downwardly from the roof rails24and terminate at a side sill (not shown). The body structure may include a plurality of cross members, such as a windshield header30, a roof bow32, and a rear header34that each extend between the roof rails24. The body structure defines a passenger cabin36configured to house occupants of the vehicle20.

The vehicle20includes an HVAC system for heating and cooling the passenger cabin36. Many three-row SUVs include vents in the dashboard as well as overhead vents above the second and third rows of seats. The dashboard vents may be part of a main HVAC system and the overhead vents may be part of an auxiliary HVAC system. Each of the HVAC systems may include a dedicated HVAC housing and blower motor and may be capable of operating independently of each other.

The vehicle20includes an auxiliary HVAC housing40connected to a body panel38near the rear wheel well. The housing40may be hidden behind the trim components of the passenger cabin36. A blower42is disposed within the housing40and powers the auxiliary HVAC system. A supply duct44supplies air to a structural air duct50that is disposed overhead of the passenger cabin36. The air duct50is arranged to blow air at the second and third rows of seats.

Typically, vehicles include structural cross member, e.g., roof bows extending between the roof rails and a separate air-duct assembly supported under the cross members. By making the air duct50structural, the cross members and the air duct can be integrated into a single, multipurpose component that replaces the multiple separate components. This integration can increase headroom, reduce the number of parts, reduce costs, and improve manufacturing efficiencies. The term “structural,” as used herein, means that the particular component or components are load bearing or otherwise provide support for the vehicle body. By making the air duct structural, the number of roof bows may be reduced.

Referring toFIGS. 1 and 3, the structural air duct50has a structural body52extending between the roof rails24and located between the rear header34and the roof bow32to be positioned above the second and third rows of seats. In one or more embodiments, the body52includes a first bow54, a second bow56, and a third bow58each extending between the roof rails24. The first bow54may include a first mounting portion64attached to the passenger-side roof rail and a second mounting portion67attached to the driver-side roof rail. The second bow56and the third bow58may have similar mounting portions attached to the roof rails24. The structural body52may be made of metal alloy, such as steel or aluminum, plastic, composite, or other suitable material. The air duct50may be attached to the roof rails24by welding, fasteners, adhesive, or any other joining technique known in the art.

Each bow may have an open top, opposing sidewalls66, and a bottom wall68that cooperate to define an open channel70. The bows may have a U-shaped, C-shaped, or tubular cross-section. A flange74may extend outwardly from a top72of each of the sidewalls. The flanges74allow the structural body52to be connected to a component such as a roof panel or a cap as will be described in more detail below. The bows54,56, and58are structural members that provide lateral support between the roof rails24to reduce lateral deflection of the vehicle sides22. The bows of the air duct50replace traditional cross members that are typically located in that area of the vehicle.

The first bow54may be interconnected with the second bow56by a front interconnecting member60, and the second bow56may be interconnected with the third bow58by a rear interconnecting member62. The interconnecting members60,62may have a U-shaped, C-shaped, or tubular cross-section. The interconnecting members may have the same cross section as the bows. The interconnecting members60,62also define open channels82that allow air to flow between the first, second, and third bows. In addition to connecting the bows in fluid communication, the interconnecting members may also add strength to the roof structure.

A roof panel84may be attached to the flanges74to cover the open top of the structural body52. Mastic, or other adhesive or sealing compound may be applied continuously along the flanges74to form an airtight seal between the roof panel84and the structural body52. The roof panel84and the structural body52cooperate to define a plenum86of the structural air duct50. The structural body52defines the sides92and bottom94of the plenum86and a bottom surface of the roof panel84defines a top90of the plenum86.

An inlet port78is defined in the structural body52and is connected to the supply duct44to connect the plenum86in fluid communication with the HVAC housing40. In the illustrated embodiment, the inlet port78is defined in the bottom wall68of the third bow58, but may be located in other locations in other embodiments. The structural body52defines at least one outlet port76allowing air to flow from the plenum86and into the passenger cabin36. In one or more embodiments, a pair of outlet ports are defined in the bottom wall68of the first bow54, and a pair of outlet ports are defined in the bottom wall68of the third bow58. The specific placement of the outlet ports may vary depending upon the layout of the passenger cabin36.

An air shutter96is disposed in each of the outlet ports76. The air shutter96may include a tubular portion received in the outlet port76and extending downwardly through a hole in the headliner98. A bezel may be formed around a perimeter of the tubular body to hide the hole in the headliner98. The air shutter96may include a plurality of blades97allowing a user to aim the air stream in a desired direction and to close the air shutter96.

The open channels70,82of the roof bows and the interconnecting members, respectively, may form individual passageways88of the plenum86. In the illustrated embodiment, all of the channels are interconnected in fluid communication with each other and all form passageways of the plenum despite outlet ports not being located on the second bow56. In other embodiments, channels not servicing outlet ports may be separated from the plenum by a blocking member or a wall. For example, the channel of bow56may be separated from the plenum86since the channel does not service an outlet port. An example of this is shown inFIG. 6and will be described in more detail below.

Referring toFIGS. 4 and 5, a vehicle100has a pair of spaced apart roof rails112and a structural air duct114connected between the roof rails112. The structural air duct114includes a structural body116having a first bow118, a second bow120, a third bow122, and interconnecting members123and125similar or identical to body52. The bows and the interconnecting members may define open channels124. The bows and interconnecting members may also include flanges126for connecting the top of the structural body116to a cap128. The cap128has a bottom side130sealed to the flanges126by mastic134or other sealing compound. The cap128cooperates with the structural body116to define a plenum136configured to distribute air to the passenger cabin. The cap128defines a top138of the plenum and the structural body116defines the sides140and the bottom142of the plenum. The cap128may be shaped to conform with the shape of the structural body116. For example, the cap128may include three transverse sections148disposed over the bows118,120,122and a pair of longitudinal sections150disposed over the interconnecting members123,125. The cap128may be a structural component or a nonstructural component, and may be formed of any suitable material such as metal alloy, plastic, or composite. A roof panel144extends between the roof rails112and is disposed over the cap128. Mastic146, or other sealing compound, joins a top side132of the cap128to a bottom side of the roof panel144.

FIG. 6illustrates structural air duct151, which is a modified version of the air duct114. Here, channels152of a second bow154are not part of a plenum160of air duct151. The channels152are separated from channel156of an interconnecting member157by a separator158. The separator158may be a wall of the interconnecting member or may be a separate blocking element, e.g., a plate, attached to interconnecting member157. The channels152are separated from the plenum160because they do not service outlet ports.

The cap162is shaped to only cover channels that form passageways of the plenum160. Thus, the plenum160includes a pair of transverse passageways164defined by a front bow172and a rear bow174, and a longitudinal passageway166defined by the interconnecting member157. Mastic168may be applied to the cap162to connect the cap162to a roof panel. Mastic170may be applied to flanges of the second bow154to connect the second bow154directly to the roof panel.

Referring toFIG. 7, the shape and configuration of the structural air duct may vary according to packaging constraints, structural constraints, and cabin layout. Vehicle180has an X-shaped structural air duct182that connects between a pair of spaced apart roof rails184. The air duct182may include transverse sections186each connected to one of the roof rails184and angled sections188that connect between the transverse sections186. The angled sections188connect with each other at a central portion to connect each of the sections in fluid communication with each other. Outlet ports190may be defined in bottom walls of the transverse sections186. The air duct182may be connected to a roof panel to seal the air duct or may include a cap that seals the air duct as described above in the previous embodiments.