Active vehicle hood system and method

A novel active hood system is disclosed. The active hood system is designed such that in the event of a pedestrian/vehicle accident, the active hood system will soften the impact between the pedestrian and the vehicle by moving the vehicle hood into an elevated position. In some embodiments, the active hood system is constructed such that during a pedestrian/vehicle collision, the active hood system will raise the vehicle hood into an elevated position by having the hood move through a first travel distance and a second travel distance. The active hood system includes an actuator and a hinge. The actuator may be attached to the hinge. The actuator is designed such that if it is deployed, the actuator will raise the hood into the elevated position. Additional embodiments may also be made in which the actuator is vented during deployment. A dampener is also added to the active hood system. The dampener is designed to dampen the movement of the hood as the hood is moved through the second travel distance.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a novel active hood system. More specifically, the present invention relates to a novel active hood system that softens the impact between the pedestrian and the vehicle hood during a pedestrian/vehicle collision.

2. Description of Related Art

Accidents in which a motor vehicle strikes a pedestrian present a serious health risk to pedestrians. In pedestrian/vehicle accidents, the heavier and larger motor vehicle impacts the smaller and lighter pedestrian with a significant amount of force. Depending on the speed and nature of the pedestrian/vehicle accident, this forcible impact between the pedestrian and the vehicle can seriously injure the pedestrian.

One type of pedestrian/vehicle accident that is particularly harmful occurs when the vehicle's front bumper or other frontal portion impacts the pedestrian's knee, leg, and/or abdominal region. Of course, this frontal impact harms the pedestrian's knee, leg, and/or abdominal region. Usually however, this frontal impact also elevates and/or flips the pedestrian such that the pedestrian's head strikes the vehicle's hood or windshield.

This second impact—the blow to the pedestrian's head—is particularly dangerous and can cause the pedestrian severe injury or trauma.

Unfortunately, the design of many currently motor vehicles can operate to heighten the severity of the impact between the pedestrian's head against the vehicle hood. For example, in vehicles such as low profile vehicles, the portion of the vehicle hood that is adjacent to the vehicle windshield is often made to be a very hard and rigid surface. Thus, if the pedestrian's head impacts this hard surface during an accident, the likelihood that the pedestrian will be injured is substantially increased.

Moreover, in order to improve the aerodynamics and visual aesthetics of the model, many vehicles are designed such that there is little or no gap between the vehicle hood and the engine that is covered by the hood. This is especially true in low profile or compact vehicle models. While this vehicle design may improve appearance, the fact that there is little or no gap between the hood and the engine means that there is little room for the hood to deform and dissipate some of the energy of the impact of the pedestrian torso and/or head. Rather, this vehicle design can actually intensify and/or focus the energy of the impact onto the pedestrian such that the likelihood of pedestrian injury is significantly increased.

Concerned about these and other safety hazards, many groups have lobbied to have additional regulations be placed upon vehicle manufacturers. Such regulations would require that all new vehicles include a safety system that is designed to protect and/or cushion the impact of a pedestrian during a pedestrian/vehicle collision. As a result of these lobbying efforts, there is now pending legislation in Korea, Japan, and Europe that would require that all new vehicles have some sort of pedestrian protection capability. The current schedule will have this legislation take effect some time between 2005 and 2010.

In order to prepare for this pending legislation, vehicle manufacturers have begun to research various safety systems and methods for protecting pedestrians during a pedestrian/vehicle collision. One type of safety system that has been particularly studied is the so-called “active hood system” which is designed such that in the event of a pedestrian/vehicle accident, the active hood system will raise all or a portion of the hood into an elevated position. By elevating the hood, the active hood system allows the hood to undergo greater deformation during the collision. In turn, this increased hood deformation allows the hood to dissipate a larger portion of the collision energy and reduces the overall severity of the impact between the pedestrian and the vehicle.

Further development indicates that in order to effectively position the hood during a collision, the active hood system must be configured to raise the hood into the elevated position within about 15 to 30 milliseconds. While such rapid movement of the hood may be achieved, such rapid movement of the hood may cause the hood to undesirably bounce or vibrate when the hood reaches the elevated position. Such bouncing of the hood is especially prone to occur in those active hood systems that do not include a dampener or other mechanism for slowing the movement of the hood.

Accordingly, there is a need in the art for a novel active hood system that addresses and/or solves one or more of the above-listed problems. Such a system and method is disclosed herein.

BRIEF SUMMARY OF THE INVENTION

The apparatus of the present invention has been developed in response to the present state of the art, and in particular, in response to the problems and needs in the art that have not yet been fully solved by currently available active hood systems. Thus, the present invention comprises an active hood system that may be positioned on a vehicle and attached to a vehicle hood. The active hood system is designed such that during a pedestrian/vehicle collision, the active hood system will soften the impact between the pedestrian and the vehicle by raising the vehicle hood into a second, elevated position. More specifically, the active hood system is constructed such that during a pedestrian/vehicle collision, the active hood system will raise the vehicle hood into an elevated position by having the hood move through a first travel distance and a second travel distance.

The active hood system includes an actuator and a hinge. The hinge may be made of metal or other similar materials. The actuator is attachable to a portion of the vehicle and may also be attached to the hinge. In some embodiments, the actuator is constructed such that it may fit within an opening on the hinge.

The actuator may be a pyrotechnic linear actuator of the type known in the art. In some embodiments, the actuator includes one or more stages. Additional embodiments may also be made in which the actuator includes one or more vent holes that are added to the stages. The actuator is constructed to have a pre-expanded configuration and an expanded configuration. Deployment of the actuator causes the actuator to expand from the pre-expanded configuration into the expanded configuration. The active hood system is designed such that when the actuator is deployed into the expanded configuration, the actuator will move the vehicle hood into an elevated position. In some embodiments, the active hood system will move the vehicle hood into an elevated position in about 30 milliseconds.

The hinge may additionally include a rotation pin. The rotation pin is configured such that a user may open the vehicle hood. More specifically, the pin is designed such that if the hinge is attached to the hood, the pin allows a user to raise a front portion of the hood so that the user may access the vehicle's engine and engine compartment that are stored beneath the vehicle hood.

The hinge may additionally include one or more linkages. The linkages are bars or other similar features that are attached to the vehicle hood and the pin. Like the actuator, the linkages have a contracted position and an extended position. The active hood system is constructed such that the deployment of the actuator causes the linkages to expand into the extended position.

The hinge may additionally comprise a holding member. The holding member is designed to hold the linkages in a contracted position. In some embodiments, the holding member is a metal plate that is attached to the hinge. However, other embodiments may also be constructed in which the holding member comprises a spring, a clip, or another similar feature that is capable of holding the linkages in a contracted position.

A locking member may also be added to the hinge. The locking member is designed to ensure that the holding member holds the linkages in a contracted position. In some embodiments, the locking member comprises a shear pin. Of course, other embodiments may also be made in which the locking member comprises a fastener or another similar feature that is capable of contacting and/or engaging the holding member.

The active hood system also includes a dampener that is constructed to dampen the movement of the vehicle hood into the elevated position. Various different types of devices or systems may be used as the dampener. In some embodiments, the active hood system is constructed such that the dampener does not dampen the movement of the vehicle hood through the first travel distance. Rather, the active hood system is designed such that the dampener operates to dampen the movement of the vehicle hood only when the hood is moved through the second travel distance.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now toFIG. 1, a perspective view of an active hood system20according to the present invention is provided. The active hood system20may be attached to a portion of a vehicle11and then positioned under a vehicle hood22. The hood22is a part of the portion of the vehicle11. The active hood system20is designed such that during a pedestrian/vehicle collision, the active hood system20will soften the impact between the pedestrian (not shown inFIG. 1) and the vehicle11by raising the vehicle hood22into a second, elevated position24(shown in phantom lines). More specifically, the active hood system20is constructed such that during a pedestrian/vehicle collision, the active hood system20will raise the vehicle hood22into an elevated position24by having the hood22move through a first travel distance26and a second travel distance28.

Like other active hood systems, the active hood system20is constructed such that during a collision, the active hood system20will rapidly raise the hood22into the elevated position. In particular, the active hood system20may be constructed such that during a collision, the hood22will be moved into the elevated position within about 15 to 30 milliseconds.

The active hood system20includes an actuator34and a hinge36. The hinge36is connected to or positioned proximate the actuator34and is designed to extend when the hood22is moved into the elevated position24. The actuator34is attachable to the vehicle11. Specifically, in the embodiment shown inFIG. 1, the hinge36is made of metal or other similar materials and comprises an actuator supporting member37that is attached to the actuator34. As shown inFIG. 1, the actuator34extends through a portion of the supporting member37. The supporting member37is made of metal or the like and is especially constructed to support and receive the actuator34. However, other embodiments may also be made in which the actuator34is attached to a different portion of the hinge36. Yet further embodiments may also be constructed in which the actuator34is not attached to the hinge36.

The hinge36may further be constructed such that the bottom of the supporting member37is attached to and/or positioned adjacent to a spring38. In turn, this spring38is attached to a base40. The base40is a metal sheet or plate that is designed to support and/or hold the active hood system20. In some embodiments, the base40is a portion of the vehicle11. Other embodiments may also be made in which the base40is a separate element that is mounted to the vehicle11via welding, fasteners, or other methods. In yet further embodiments, the actuator34and/or the actuator supporting member37may be directly mounted to the vehicle11.

The actuator34may be a pyrotechnic linear actuator of the type known in the art. One example of a pyrotechnic linear actuator that may be used as the actuator34is disclosed in U.S. Patent Application Publication No. 2004/0006979, which is owned by the assignee of the present application and is incorporated herein by reference. However, embodiments may also be made in which other types of devices and/or actuators are used as the actuator34.

The actuator34has a pre-expanded configuration and an expanded configuration. As shown inFIG. 1, the actuator34is in the pre-expanded configuration. Deployment of the actuator34causes the actuator34to expand from the pre-expanded configuration into the expanded configuration. Specifically, the active hood system20is designed such that when the actuator34is deployed into the expanded configuration, the actuator34will move the vehicle hood22into an elevated position24.

Referring still toFIG. 1, the hinge36may additionally include a rotation pin42. The rotation pin42is configured such that a user (not shown) may open the vehicle hood22. More specifically, the pin42is designed such that if the hinge36is attached to the hood22, the pin42allows a user to raise a front portion of the hood22so that the user may access the vehicle's engine and engine compartment that are stored beneath the vehicle hood22.

The hinge36may additionally include one or more linkages44. The linkages44are bars or other similar features that are attached to the vehicle hood22and the pin42. Specifically, the linkages44are attached to an extension35, which in turn, is attached to the vehicle hood22. Like the actuator34, the linkages44have a contracted position and an extended position. As illustrated inFIG. 1, the linkages44are in the contracted position. The active hood system20is constructed such that the deployment of the actuator34causes the linkages44to expand into the extended position (shown inFIG. 4).

The hinge36may additionally comprise a holding member46. The holding member46is designed to hold the linkages44in a contracted position. As illustrated inFIG. 1, the holding member46is a metal plate that is attached to the hinge36via a locking rotation pin45. Of course, other embodiments may also be made in which the holding member46comprises a spring, a clip, or another similar feature that is capable of holding the linkages in a contracted position.

A locking member48may also be added to ensure that the holding member46holds the linkages44in a contracted position. In the embodiment shown inFIG. 1, the locking member48comprises a shear pin50. However, other embodiments may also be made in which the locking member48comprises a fastener or another similar feature that is capable of contacting and/or engaging the holding member46.

The active hood system20also includes a dampener60. The dampener60includes a retention bracket62that houses a crushing flange64and a deformable material66. The flange64is positioned below the deformable material66. In some embodiments, the deformable material66comprises a block of aluminum honeycomb of the type disclosed in U.S. Pat. No. 6,237,955, which patent is incorporated herein by reference. However, embodiments may also be made in which other materials or features that are capable of being crushed and/or deformed are used as the deformable material66.

A cable70is also added to the dampener60. The cable70includes a first end72and a second end74. The first end72is attached to the crushing flange64whereas the second end74is attached to an eyelet76positioned on the vehicle hood22.

The dampener60is constructed such that during a portion of the deployment of the actuator34, the dampener60operates to dampen the movement of the vehicle hood22into the elevated position24. As will be discussed in greater detail below, this dampening occurs by crushing the dampening material66between the flange64and the retention bracket62.

Referring now toFIG. 2, the operation of the active hood system20will be described in greater detail. In the event that a sensor (not shown) detects a collision or accident between a pedestrian and the vehicle11, a signal will be sent to the actuator34. This signal causes the actuator34to produce a volume of inflation gas (not shown) and deploy.

As the actuator34begins to deploy, the actuator34applies a load or force onto the locking member48. Such loading of the locking member48will break and/or unlock the locking member48. In the embodiment shown inFIG. 2in which the locking member48comprises the shear pin50, the application of the load to the shear pin50operates to break the shear pin50.

Once the locking member48has been broken or unlocked, the deployment of the actuator34rotates the holding member46about the locking rotation pin45such that all or a portion of the holding member moves towards the actuator34. In turn, such movement of the holding member46disengages the holding member46from the pin42and unlocks the linkages44.

In the embodiment shown inFIG. 2, the active hood system10is further designed such that deployment of the actuator34also moves a bottom portion80of the actuator34towards the base40and/or away from the hinge36. However, such a feature is not limiting. Other embodiments may also be made in which the deployment of the actuator34also moves a bottom portion80of the actuator34away from the base40and/or towards the hinge36. Yet further embodiments may be made in which the position of the bottom portion80remains constant throughout the deployment of the actuator14.

Referring still toFIG. 2, the actuator34includes one or more telescoping stages82. The stages82are positioned on the interior of the actuator34when the actuator34is in the pre-expanded configuration. However, as illustrated inFIG. 2, when the actuator34is deployed into the expanded configuration, the stages82extend from a top portion84of the actuator34. In some embodiments, the actuator34is constructed such that the stage82with the largest diameter has a diameter that is equal to about two inches.

Referring now toFIG. 3, the movement of the vehicle hood22through the first travel distance26is depicted. As can be seen inFIG. 3, as the actuator34is deployed the stages82exert an upward force (represented graphically by an arrow88) upon the vehicle hood22. It is this application of the upwardly directed force88that causes the vehicle hood22to move through the first travel distance26.

In the embodiment depicted inFIG. 3, the first travel distance26is shown as being more than (i.e. greater than) the second travel distance28. However, other embodiments may also be made in which the first travel distance26is less than (i.e. smaller than) the second travel distance28. Still additional embodiments may also be made in which the first travel distance26is equal to the second travel distance28

The active hood system20shown inFIG. 3is further constructed such that the dampener60does not dampen or otherwise affect the movement of the vehicle hood22through the first travel distance26. Rather, the active hood system20is constructed such that the movement of the vehicle hood22through the first travel distance26removes the slack from the cable70. However, other embodiments may also be made in which the dampener60operates to dampen the movement of the vehicle hood22through the first travel distance26.

FIG. 3also illustrates the movement of the linkages44as the actuator34is being deployed. As described above in greater detail, the deployment of the actuator34unlocks the linkages44by disengaging the holding member46from the pin42. Once the linkages44have been unlocked, the active hood system20is designed such that the movement of the vehicle hood22through the first travel distance26also operates to upwardly move the linkages44out of the contracted position.

Referring now toFIG. 4, the movement of the vehicle hood22through the second travel distance28and into the elevated position24is depicted.FIG. 4also shows a pedestrian94. (Note that the system20is not deployed while the pedestrian is on the hood22. Rather, the system20deploys prior to the pedestrian94contacting the hood22). The movement of the hood22by the system20softens the impact of the pedestrian94with the hood22. More specifically, such movement of the hood22softens the impact of the pedestrian's head94aand/or torso94bwith the hood22. As withFIG. 3, the movement of the vehicle hood22through the second travel distance28is caused by the stages82being extended from of the actuator34. More specifically, as the stages82are being extended from the actuator34, the stages82exert an upward force88on the vehicle hood22that pushes and/or moves the vehicle hood22through the second travel distance28.

As illustrated inFIG. 4, the movement of the vehicle hood22through the second travel distance28also moves the linkages44into a fully extended position. One or more tabs89,89amay also be added to the hinge36and/or the linkages44to ensure that the movement of the vehicle hood22through the second travel distance28does not over-extend the linkages44.

In the embodiment shown inFIG. 4, the active hood system20is constructed such that as the vehicle hood22moves through the second travel distance28, the movement of the hood22is dampened by the dampener60. This dampening may be accomplished by crushing the deformable material66between the flange64and the retention bracket62. More particularly, as the vehicle hood22moves through the second travel distance28, the upward movement of the hood22tensions the cable70. In turn, the tensioned cable70pulls the flange64such that the flange64moves and crushes the deformable material66between the retention bracket62and the flange64. This crushing of the deformable material66dissipates a portion of the energy of the hood22and dampens the movement of the vehicle hood22.

The system20may additionally be constructed such that when the hood22is impacted by the pedestrian94, the force of the impact will compress a portion of the actuator34and/or the stages82. In some embodiments, such compression of the actuator34and/or stages operates to further dissipate some of the energy of the impact.

FIG. 5is a perspective view that illustrates additional features that may be added to the actuator34and/or the hinge36. As shown inFIG. 5, the actuator supporting member37may include at least one slot93that extends into a central aperture95. The central aperture95is sized and configured to receive and hold the actuator34. Additionally, the actuator34may additionally comprise a cylindrical groove97with one or more mating flats98that have been machined into the groove97. The groove97is a depression in the exterior of the actuator34whereas the mating flats98are sections of the groove97that have a perpendicular cross-section.

FIG. 5also illustrates a method by which the actuator34may be attached and/or mounted to the hinge36. Specifically, such attachment occurs by aligning the flats97on the actuator34with the slot93on the supporting member37. When the flats98have been aligned, the actuator34may then be slid into the central aperture95as illustrated by the arrow99. Once the actuator34has been positioned within the aperture95, the actuator34may then be rotated so that the flats98are no longer aligned with the slot93. Such rotation of the actuator34allows the actuator34to be tightly retained within the aperture95.

The above-recited method for attaching the actuator34to the hinge36also provides an easy mechanism for removing the actuator34from the hinge36. Such removal of the actuator34after deployment of the actuator34and/or during routine maintenance of the active hood system20. In order to remove the actuator34, the actuator34within the aperture95, the actuator34is first rotated so that the flats98are aligned with the slot93. When the flats98are aligned, the actuator34may then be removed from the supporting member by having the actuator34slide through the slot93in the direction opposite the arrow99. Once the actuator34has been removed, a new actuator34may then be installed into the active hood system20, and system20may be used again. The locking member48may also be re-installed onto the system20to ensure that the holding member46holds the linkages44in a contracted position.

WhileFIG. 5shows one easy method for attaching the actuator34to the hinge36, those of skill in the art will recognize that other embodiments may also be made in which the actuator34is not attached to the hinge36. Further embodiments may be made in which the actuator34is attached to the hinge36through methods and/or systems that differ from that which is illustrated inFIG. 5. For example, embodiments may also be made in which the actuator34is held within the aperture95by a spring clip, a cinch nut, or another similar feature. Additional embodiments may have the actuator34include a threaded nut that will engage a threaded actuator post positioned within the aperture95. Yet further embodiments may attach the actuator34to the hinge36and/or the aperture95via fasteners, welding, or other similar methods.

Referring now toFIG. 6, an additional embodiment of the present invention is depicted.FIG. 6shows an active hood system120in its undeployed, pre-expanded configuration. The active hood system120is similar to the active hood system20discussed in conjunction withFIGS. 1-5. In fact, the only difference between the embodiment shown inFIG. 6and the embodiment shown inFIGS. 1-5is that inFIG. 6, the active hood system120includes a dampener160as opposed to the dampener60discussed above.

The dampener160is constructed such that during a portion of the deployment of the actuator34, the dampener160operates to dampen the movement of the vehicle hood22into the elevated position24. In some embodiments, the dampener160is similar to and/or based upon the technology disclosed in one or more of the following patents: U.S. Pat. No. 5,235,734, U.S. Pat. No. 4,867,003, U.S. Pat. No. 3,788,148, and U.S. Pat. No. 3,392,599, which patents are expressly incorporated herein by reference.

Specifically, the dampener160includes a deformable tube162that is connected to the base40and/or a portion of the vehicle (not shown). The dampener160also includes a cable170having first end172and a second end174. The first end172is positioned within the deformable tube162whereas the second end174is attached to an eyelet176that is positioned on the vehicle hood22.

A deforming ball178is also added to the dampener160. The deforming ball178is attached to the first end172and is positioned within the deformable tube162. As will be discussed in greater detail below, the deforming ball178is constructed such that it may dampen the movement of the actuator34by deforming and/or crushing the deformable tube162.

Referring now toFIG. 7, the active hood system20is illustrated after the actuator34has moved the vehicle hood22through the first travel distance26. Specifically, as the actuator34is deployed, the stages82exert an upward force (represented graphically by an arrow88) upon the vehicle hood22. It is this application of the upwardly directed force88that causes the vehicle hood22to move through the first travel distance26.

In the embodiment shown inFIG. 7, the active hood system120is constructed such that the dampener160does not dampen or otherwise affect the movement of the vehicle hood22through the first travel distance26. Rather, the active hood system120is constructed such that the movement through the first travel distance26removes the slack from the cable170. However, other embodiments may also be made in which the dampener160operates to dampen the movement of the vehicle hood22through the first travel distance26.

Referring now toFIG. 8, the active hood system120is illustrated after the vehicle hood22has been moved through the second travel distance28into the elevated position24. As withFIG. 7, the movement of the vehicle hood22through the second travel distance28is caused by the stages82being extended from the actuator34. More specifically, as the stages82are being extended from the actuator34, the stages82exert an upward force88on the vehicle hood22that pushes and/or moves the vehicle hood22through the second travel distance28.

Like the embodiment shown inFIGS. 1-5, the active hood system120is constructed such that as the vehicle hood22moves through the second travel distance28, the dampener160dampens the movement of the hood22. This dampening may be accomplished by deforming the deformable tube162. More particularly, as the vehicle hood22moves through the second travel distance28, the upward movement of the hood22tensions the cable170. This tensioned cable170then pulls the deforming ball178upwards and causes the deforming ball178to deform all or a portion of the deformable tube162. In turn, this deforming of the deformable tube162dissipates a portion of the energy of the hood22and dampens the movement of the vehicle hood22.

Referring now toFIG. 9, a further embodiment of the present invention is depicted.FIG. 9shows an active hood system220in its undeployed, pre-expanded configuration. The active hood system220is similar to the active hood systems20,120described above in conjunction withFIGS. 1-8. In fact, the only differences between the embodiment shown inFIG. 9and the embodiments shown inFIGS. 1-8is that inFIG. 9, the vehicle hood22has been replaced with a new hood222and the dampener60,160has been replaced with a new dampener260.

The vehicle hood222that is used as part of the active hood system220is similar to the vehicle hood22that is discussed above. Accordingly, the vehicle hood222is capable of being raised into the elevated position24(shown in phantom lines) in order to soften the impact between the pedestrian94(not shown inFIG. 9) and the vehicle (not shown). More specifically, the active hood system220is constructed such that during a pedestrian/vehicle collision, the active hood system220will deploy the actuator34and raise the hood222into an elevated position24(shown in phantom) by having the hood222move through the first travel distance26and the second travel distance28.

The actuator34may also include a retention stake34aand the hood222may also include a receiving area34bthat is designed to receive the stake34a. Specifically, the system220is designed such that when the actuator34is deployed, the actuator34will engage the hood222by having the stake34aengage and/or be inserted into the receiving area34b.

Like the embodiments described above, the embodiment shown inFIG. 9has been constructed such that the first travel distance26is greater than the second travel distance28. However, other embodiments may also be constructed in which the first travel distance26is less than the second travel distance28. Still further embodiments may be constructed in which the first travel distance26is equal to the second travel distance28.

Like the embodiments described above, the dampener260is constructed such that during a portion of the deployment of the actuator34, the dampener260operates to dampen the movement of the vehicle hood222into the elevated position24. However, unlike the previously described dampeners60,160, the dampener260includes a dampening bellows262that has an upper surface264and a lower surface266. The upper surface264is attached to the vehicle hood222whereas the lower surface266is attached to the top portion84of the actuator34. Of course in other embodiments, the lower surface266may be attached to one or more of the stages82(not shown inFIG. 9) and/or another portion of the actuator34.

Referring now toFIG. 10, the active hood system220is illustrated after the actuator34has moved the vehicle hood222through the first travel distance26. Specifically, as the actuator34is deployed, the stages82exert an upward force (represented graphically by an arrow88) upon the vehicle hood222. It is this application of the upwardly directed force88that causes the vehicle hood222to move through the first travel distance26.

In the embodiment shown inFIG. 10, the active hood system220is constructed such that the dampener260does not dampen or otherwise affect the movement of the vehicle hood222through the first travel distance26. However, other embodiments may also be made in which the dampener260operates to dampen the movement of the vehicle hood222through the first travel distance26.

Referring now toFIG. 11, the active hood system220is illustrated after the vehicle hood222has been moved through the second travel distance28into the elevated position24. As withFIG. 10, the movement of the vehicle hood222through the second travel distance28is caused by the stages82being extended from the actuator34. More specifically, as the stages82are being extended from the actuator34, the stages82exert an upward force88on the vehicle hood222that pushes and/or moves the vehicle hood222through the second travel distance28.

Like the embodiments discussed above, the active hood system220is constructed such that as the vehicle hood222moves through the second travel distance28, the dampener260dampens the movement of the hood222. Such dampening may be accomplished by opening the bellows262. More particularly, as the vehicle hood222moves through the second travel distance28, the kinetic energy and/or the inertia of the hood222causes the bellows262to open into an expanded configuration270. This expansion of the bellows262dissipates some of the kinetic energy of the hood222and operates to dampen the movement of the hood222.

Referring now toFIG. 12, a further embodiment of the present invention is depicted.FIG. 12shows an active hood system320in its undeployed, pre-expanded configuration. The active hood system320is similar to the active hood systems20,120,220described above in conjunction withFIGS. 1-11. In fact, the only differences between the embodiment shown inFIG. 12and the embodiments shown inFIGS. 1-11is that inFIG. 12, the vehicle hoods22,222have been replaced with a new hood322, the actuator34has been replaced by a new actuator334, and the dampeners60,160,260have been replaced with a new dampener360.

The vehicle hood322that is used as part of the active hood system320is similar to the vehicle hoods22,222discussed above. Accordingly, the vehicle hood322is capable of being raised into the elevated position24(shown in phantom lines) in order to soften the impact between the pedestrian94(not shown inFIG. 12) and the vehicle (not shown). More specifically, the active hood system320is constructed such that during a pedestrian/vehicle collision, the active hood system320will deploy the actuator334and raise the hood322into an elevated position24(shown in phantom) by having the hood322move through the first travel distance26and the second travel distance28.

Furthermore, the actuator334that is used as part of the active hood system320is similar to the actuator34discussed above. The actuator has a top portion384and a bottom portion380. The actuator334includes one or more telescoping stages382(shown inFIG. 13) that are positioned on the interior of the actuator334when the actuator334is in the pre-expanded configuration. The actuator334is designed such that when the actuator334is deployed, the stages382will extend from a top portion384of the actuator334and move the vehicle hood322through the first travel distance26and the second travel distance28(seeFIGS. 13 and 14).

Like the embodiments described above, the dampener360is constructed such that during a portion of the deployment of the actuator334, the dampener360operates to dampen the movement of the vehicle hood322into the elevated position24. However, unlike the previously described dampeners60,160,260, the dampener360comprises a retention stake362. The retention stake362is connected to and/or positioned on the top portion384. Of course, other embodiments may also be made in which the retention stake362is attached to one or more of the stages382and/or another portion of the actuator334.

A stake retention hole364that is designed to receive the retention stake362is also added to the active hood system320. The stake retention hole364is added to the vehicle hood322. Specifically, the stake retention hole364is added to the vehicle hood322and is configured such that the position of the stake retention hole364corresponds to the position of the retention stake362.

Referring now toFIG. 13the active hood system320is illustrated after the actuator334has moved the vehicle hood322through the first travel distance26. Specifically, as the actuator334is deployed, the stages382exert an upward force (represented graphically by an arrow388) upon the vehicle hood322. It is this application of the upwardly directed force388that causes the vehicle hood322to move through the first travel distance26.

In the embodiment shown inFIG. 13, the active hood system320is constructed such that the dampener360does not dampen or otherwise affect the movement of the vehicle hood322through the first travel distance26. Rather, as shown inFIG. 13, the deployment of the actuator334and/or the movement of the vehicle hood322through the first travel distance26does not affect the stake362or the stake retention hole364. Of course, other embodiments may also be made in which the movement of the vehicle hood322through the first travel distance26operates to lockingly engage the retention stake362within the stake retention hole364. Still further embodiments may be made in which the dampener360dampens the movement of the vehicle hood322through the first travel distance26.

Referring now toFIG. 14, the active hood system320is illustrated after the vehicle hood322has been moved through the second travel distance28into the elevated position24. As withFIG. 13, the movement of the vehicle hood322through the second travel distance28is caused by the stages382being extended from the actuator334. More specifically, as the stages382are being extended from the actuator334, the stages382exert an upward force388on the vehicle hood322that pushes and/or moves the vehicle hood322through the second travel distance28.

The active hood system320is constructed such that as the vehicle hood322moves through the second travel distance28, the dampener360dampens the movement of the hood322. Such dampening may be accomplished by the engagement between the retention stake362and the stake retention hole364. More specifically, the engagement between the retention stake362and the stake retention hole364operates to connect the vehicle hood322with the actuator334. Accordingly, when the vehicle hood322is moved through the second travel distance28, the kinetic energy and/or inertia of the moving vehicle hood322expands the actuator334an additional distance (represented graphically by the arrows391). It is this additional expansion391of the actuator334that operates to dampen the movement of the vehicle hood322.

Referring now toFIG. 15, a perspective view of a hinge436is illustrated. The hinge436is similar to the hinge36discussed above. The hinge436is specifically designed such that it may be used as part of the active hood systems20,120,220,320. The hinge436shown inFIG. 15has been attached to the actuator34and is constructed to extend when a vehicle hood22(not shown inFIG. 15) is moved into an extended position24(not shown inFIG. 15). Of course, those of skill in the art will recognize that other embodiments may be made in which the hinge436is separate from the actuator34. Still further embodiments may be made in which the hinge436is attached to and/or used in conjunction with a different type of actuator, such as the actuator334.

As with the hinge36, the hinge436is also attachable to a vehicle hood22and may include an actuator supporting member437. The supporting member437is a plate or other similar feature that is designed to support and receive the actuator34. A spring38(not shown inFIG. 15) may also be added to the hinge436. The spring is attached to the bottom of the supporting member437. In turn, this spring may be is attached to a base440. The base440is a metal sheet or plate that is designed to support and/or hold the active hood system20,120,220,320. In some embodiments, the base440is a portion of the vehicle. Other embodiments may also be made in which the base440is a separate element that is mounted to the vehicle via welding, fasteners, or other methods.

The hinge436may additionally include a rotation pin442. The rotation pin442is configured such that a user (not shown) may open the vehicle hood22. More specifically, the pin442is designed such that if the hinge436is attached to the hood22, the pin442allows a user to raise a front portion of the hood22so that the user may access the vehicle's engine and engine compartment that are stored beneath the vehicle hood22.

The hinge436may additionally include one or more linkages444. The linkages444are bars or other similar features that are attached to the vehicle hood22and the pin442. Like the embodiment described above, the linkages444have a contracted position and an extended position. As illustrated inFIG. 15, the linkages444are in the contracted position.

Referring still toFIG. 15, the hinge436may additionally comprise a holding member446. The holding member446is designed to hold the linkages444in a contracted position. However, unlike the hinge36described above, the hinge436has been designed such that the holding member446comprises a clip447. The clip447is made of plastic or other similar materials and is designed such that when the linkages444are in the contracted position, the clip447will cover all or a portion of the linkages444.

The clip447is further designed such that when the actuator34is deployed, the actuator34causes the clip447to disengage from the linkages444. Once the clip447is disengaged, the linkages444are free to move into the extended position in the manner described above. In some embodiments, this disengagement of the clip447may be accomplished by configuring the hinge436such that the deployment of the actuator34operates to break the clip447. In other embodiments, this disengagement of the clip447may be accomplished by configuring the hinge436such that the deployment of the actuator34removes and/or prevents the clip447from covering the linkages444.

Referring now toFIG. 16, a perspective view of a hinge536is illustrated. The hinge536is similar to the hinge36,436discussed above. The hinge536is specifically designed such that it may be used as part of the active hood systems20,120,220,320. The hinge536shown inFIG. 16has been attached to the actuator34and is constructed to extend when a vehicle hood22(not shown inFIG. 16) is moved into an extended position24(not shown inFIG. 16). Of course, those of skill in the art will recognize that other embodiments may be made in which the hinge536is separate from the actuator34. Still further embodiments may be made in which the hinge536is attached to and/or used in conjunction with another type of actuator, such as the actuator334.

As with the hinge36,436, the hinge536is attachable to a vehicle hood22and may include an actuator supporting member537. The supporting member537is a plate or other similar feature that is designed to support and receive the actuator34. A spring38(not shown inFIG. 16) may also be added to the hinge536. The spring is attached to the bottom of the supporting member537. In turn, this spring may be is attached to a base540. The base540is a metal sheet or plate that is designed to support and/or hold the active hood system20,120,220,320. In some embodiments, the base540is a portion of the vehicle. Other embodiments may also be made in which the base540is a separate element that is mounted to the vehicle via welding, fasteners, or other methods.

The hinge536may additionally include a rotation pin542. The rotation pin542is configured such that a user (not shown) may open the vehicle hood22. More specifically, the pin542is designed such that if the hinge536is attached to the hood22, the pin542allows a user to raise a front portion of the hood22so that the user may access the vehicle's engine and engine compartment that are stored beneath the vehicle hood22.

The hinge536may additionally include one or more linkages544. The linkages544are bars or other similar features that are attached to the vehicle hood22and the pin542. Like the embodiments described above, the linkages544have a contracted position and an extended position. As illustrated inFIG. 16, the linkages544are in the contracted position.

Referring still toFIG. 16, the hinge536may additionally comprise a holding member546. The holding member546is designed to hold the linkages544in a contracted position. A locking member548may also be added to ensure that the holding member546holds the linkages544. As illustrated inFIG. 16, the locking member548comprises a shear pin550. However, other embodiments may also be made in which the locking member548comprises a fastener or another similar feature that is capable of contacting and/or engaging the holding member546.

As with the hinge436described above, the hinge536has been designed such that the holding member546comprises a clip547. Unlike the clip447however, the clip547is made of metal and is designed such that when the linkages544are in the contracted position, the clip547will engages the sides of the linkages544.

The clip547is further designed such that when the actuator34is deployed, the actuator34causes the clip547to disengage from the linkages544. Once the clip547is disengaged, the linkages544are free to move into the extended position in the manner described above. In some embodiments, this disengagement of the clip547may be accomplished by configuring the hinge536such that the deployment of the actuator34operates to break the clip547. In other embodiments, this disengagement of the clip547may be accomplished by configuring the hinge536such that the deployment of the actuator34removes and/or prevents the clip547from contacting the linkages544. An additional feature of the clip547is that after deployment of the hood lifting system (especially in the case of a “false” deployment) and removal of actuator34, the linkages544can be snapped back into place, and the vehicle in which the system is used could be driven again.

Referring now toFIG. 17, a cross-sectional view illustrates an additional embodiment of an actuator634. The actuator634is similar to the actuator34,334described in conjunction withFIGS. 1-16. In fact all or the features or elements found in the actuators34,334, may be added to the actuator634. Likewise all of the features or elements found in the actuators described in U.S. Patent Application Publication No. 2004/0006979 (which application, as noted above, is incorporated herein by reference) may similarly be added to the actuator634. For purposes of clarity however, such features and elements are not illustrated inFIG. 17.

As with the actuators34,334, the actuator634comprises one or more stages telescoping682. The stages682may be in either a pre-expanded configuration or an extended configuration. As shown inFIG. 17, the stages682are in the pre-expanded configuration. However, the actuator634is constructed such that when the actuator634is deployed, the stages682will convert into the extended configuration by expanding or extending through a top portion684of the actuator634.

Like the actuator disclosed U.S. Patent Application Publication No. 2004/0006979, the stages682may be deployed via an initiator639and a supply of gas generant641. More specifically, the actuator634is designed such that when the appropriate signal is given, the initiator639will ignite the gas generant641. In turn, this ignition of the gas generant641produces a large volume of inflation gas (not shown). The inflation gas then pushes against the stages682and causes the stages to extent from the top portion684of the actuator634.

Referring still toFIG. 17, the actuator634may additionally comprise one or more vent holes690. The vent holes690are apertures or openings in the stages682. In the embodiment shown inFIG. 17, two vent holes690have been added to the stages682. However, other embodiments may also be made in which three, four, or even more than four vent holes690are added to the actuator634.

The actuator634may further comprise one or more integral flanges691that seal and/or cover the vent holes690. For purposes of clarity, one of the flanges691has been removed fromFIG. 17so that the vent hole690may be illustrated. The flanges691may be made of plastic, metal, nylon, or other similar materials that are capable of sealing the vent holes690. Additional embodiments may also be made in which other methods are used for sealing the vent holes690. For example, embodiments may also be made in which the vent holes690are sealed by burst disks, plugs, or any other member that engages and/or fits into the vent holes690.

Referring now toFIG. 18, the actuator634is shown as part of an active hood system620. The active hood system620is shown in its undeployed, pre-expanded configuration and includes the hinge36. The active hood system620is similar to the active hood systems20,120,220,320described in conjunction withFIGS. 1-14. The actuator634may also be used in conjunction with the hinges436,536discussed inFIGS. 15 and 16.

The active hood system620includes a vehicle hood622. The vehicle hood622is similar to the vehicle hoods22,222,322that discussed above. Accordingly, the vehicle hood322is capable of being raised into the elevated position24(shown in phantom lines) in order to soften the impact between the pedestrian94(not shown inFIG. 18) and the vehicle (not shown). More specifically, the active hood system620is constructed such that during a pedestrian/vehicle collision, the active hood system620will deploy the actuator634and raise the hood622into an elevated position24(shown in phantom) by having the hood622move through the first travel distance26and the second travel distance28.

The active hood system620also includes a dampener660. The dampener660is constructed such that during a portion of the deployment of the actuator634, the dampener660operates to dampen the movement of the vehicle hood622into the elevated position24. The dampener660is similar and/or identical to the dampener60shown inFIGS. 9-11. Accordingly, the dampener660includes a retention bracket662that houses a crushing flange64and a deformable material666. The flange664is positioned below the deformable material666. A cable670is also added to the dampener660. The cable670includes a first end672and a second end674. The first end672is attached to the crushing flange664whereas the second end674is attached to an eyelet676positioned on the vehicle hood622.

Although the embodiment shown inFIG. 18shows the actuator634used in conjunction with the dampener660, other embodiments may also be made in which the actuator634is used with other types of dampeners. For example, embodiments may also be made in which the actuator634is attached to and/or used in conjunction with the dampeners60,160,260,360discussed above in conjunction withFIGS. 1-14. Of course, yet further types of dampeners may also be used.

Referring now toFIG. 19, the active hood system620is illustrated after the actuator634has moved the vehicle hood622through the first travel distance26. Specifically, as the actuator634is deployed, the stages682exert an upward force (represented graphically by an arrow688) upon the vehicle hood622. It is this application of the upwardly directed force688that causes the vehicle hood622to move through the first travel distance26.

In the embodiment shown inFIG. 19, the active hood system620is constructed such that the dampener660does not dampen or otherwise affect the movement of the vehicle hood622through the first travel distance26. However, other embodiments may also be made in which the dampener660does dampen the movement of the vehicle hood622through the first travel distance26.

Referring now toFIG. 20, the active hood system620is illustrated after the vehicle hood622has been moved through the second travel distance28into the elevated position24. As withFIG. 19, the movement of the vehicle hood622through the second travel distance28is caused by the stages682being extended from of the actuator34. More specifically, as the stages682are being extended from the actuator34, the stages682exert an upward force688on the vehicle hood622that pushes and/or moves the vehicle hood622through the second travel distance28.

Like the embodiments discussed above, the active hood system620is constructed such that as the vehicle hood622moves through the second travel distance28, the dampener660dampens the movement of the hood622. Such dampening may be accomplished by crushing the dampening material666. More particularly, as the vehicle hood622moves through the second travel distance28, the kinetic energy and/or the inertia of the hood622causes the flange664to move and crush the dampening material666. Such crushing of the dampening material666dissipates some of the kinetic energy of the hood622and operates to dampen the movement of the hood622.

As can be seen inFIG. 20, when the actuator634is deployed, the stages682are extended upwards a first distance686and a second distance687. In some embodiments, the actuator634is further constructed such that when the stages682are extended out the first distance686, the actuator634is sealed whereas when the stages682are extended out the second distance687, the actuator634is unsealed. In the embodiment shown inFIG. 20, such sealing and unsealing of the actuator634may be accomplished via the vent holes690. Specifically, the actuator634is configured such that when the stages682are extended out the first distance686, the vent holes690are sealed by the flanges691(shown inFIG. 17). However, when the stages682are extended out the second distance687, the flanges691disengage from the vent holes690. This disengagement of the plug691from the vent holes690unseals the actuator634. In turn, this unsealing of the vent holes690allow pressurized gas (illustrated graphically by arrow692) to bleed out from the interior of the actuator634until the pressure on the interior of the actuator634is equal or substantially equal to the pressure on the exterior of the actuator634.

In the embodiment shown inFIG. 20, the active hood system620is constructed such that the stages682will extend out the second distance687as the hood622is moved through the second travel distance28. More specifically, the active hood system620is constructed such that the stages682will extend the second distance687while the hood622is moved through the second travel distance28and after the hood622as moved a distance that is equal to about 90 percent of the total distance traveled by the vehicle hood622. Of course, other embodiments may also be constructed in which the stages682extend the second distance687before the vehicle hood622has moved a distance that is equal to about 90 percent of the total distance traveled by the vehicle hood622. Still further embodiments may be made in which the stages682extend the second distance687after the vehicle hood622has moved a distance that is equal to about 90 percent of the total distance traveled by the vehicle hood622. Yet further embodiments may be made in which the stages682extend the second distance687as the movement of the vehicle hood622is being dampened by the dampener660. Other embodiments may also be constructed in which the stages682extend the second distance as the hood622is moved through the first distance26.

Although the embodiment shown inFIG. 20has been constructed such that the actuator634is unsealed by removing the flanges691from the vent holes690, other methods of unsealing the actuator634may also be used. For example, embodiments may be used in which the actuator634is unsealed via puncturing. In some embodiments, this puncturing of the actuator634may be accomplished by rupturing a burst disk and/or a plug that is used to cover and/or seal one or more of the vent holes690. Such puncturing of the actuator634may occur while the hood622is moved through the first travel distance26and/or the second travel distance28. Still additional embodiments may be made such that when the actuator634is unsealed, the actuator634looses its ability to move the hood622.

By constructing the actuator634such that the gas692may be vented out as the actuator634is being deployed, additional advantages and/or cushioning to the pedestrian94may be achieved during a during a pedestrian/vehicle collision. Specifically, when the pedestrian94impacts the vehicle hood622during a pedestrian/vehicle collision, the pedestrian94will impart a compressive load (represented graphically by an arrow696) onto the vehicle hood622. Since the actuator634has been de-pressurized through the venting of the gas692through the vent holes690, this load696will compress the actuator634by forcing the stages682into the interior of the actuator634. In turn, this compression of the stages682dampens a portion of the energy of the collision and softens the impact between the pedestrian94and the vehicle hood622. Additional attenuation of energy may be achieved by configuring the active hood system620such that the momentum of the moving hood622pulls the stages682out some distance from the top portion684of the actuator634.

In summary, the present invention provides a novel active hood system that reduces the severity of a pedestrian/vehicle collision. As such, many of the limitations associated with known active hood systems may be effectively eliminated.