Patent Publication Number: US-6655733-B2

Title: Variable movement headrest arrangement

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. provisional application Ser. Nos. 60/302,016; 60/302,024; and 60/302,019, all filed on Jun. 29, 2001. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a variable movement headrest arrangement for providing support to the head of an occupant of a vehicle upon vehicle impact. 
     2. Background Art 
     Improvements in safety mechanisms in the automotive industry continue to be made year after year. Such safety mechanisms include safety headrests. An example of safety seat headrests can be found in Viano et al., U.S. Pat. No. 5,378,043, which is incorporated herein by reference. Such safety headrest mechanisms provide support to the head of a vehicle occupant during crash situations. 
     More specifically, upon rear impact of a vehicle, the occupant of the vehicle compresses into the vehicle seatback, as the head, neck, and torso move substantially in unison. There typically is greater compression in the torso and buttocks regions than in the shoulder region of the occupant. Thus, it has been a concern that the seatback may possibly deflect under the torso and buttocks load before the head and neck of the occupant contacts the headrest attached to the seatback. 
     Upon front impact of a vehicle, an occupant of the vehicle moves forward relative to the vehicle seatback. Upon contact with a front interior panel or a deployed airbag from the front panel, the occupant experiences rebound movement in a rearward direction. Similar to a rear impact situation as described above, the occupant in such a situation would then provide a rearward load into the seatback and compress into the vehicle seatback, as the head, neck, torso, and buttocks move substantially in unison. Thus, in a front impact it is also a concern that the seatback may possibly deflect under the torso load prior to the head and neck of the occupant contacting the headrest. 
     As a result, safety headrest mechanisms have been designed such that, upon impact having rearward movement of a seat occupant, the occupant&#39;s torso contacts an impact target of a vehicle seat with a rearward load or force. The impact target is operatively connected to a headrest or such that, upon the rearward load on the impact target, the headrest portion moves forward toward the head of the occupant. The forward movement of the headrest portion in the crash situation lessens the gap which may exist between the occupant&#39;s head and the headrest portion, preventing or lessening the risk of whiplash to the occupant. 
     However, it is desirable to have the headrest arrangement move forward at a high initial velocity in order to decrease the gap between the occupant&#39;s head and headrest portion more quickly, but without contacting the occupant&#39;s head while moving at the high initial velocity. 
     SUMMARY OF THE INVENTION 
     It is thus an object of the present invention to provide a cost effective mechanism to support the head of an occupant of a vehicle upon front and rear vehicle impact. 
     In carrying out the above object, and other objects and features of this invention, a new vehicle seat and headrest arrangement for use with a seat having a seatback in a vehicle is provided. The vehicle seat and headrest arrangement comprises a headrest arrangement having a headrest, the headrest arrangement having one of a guide member and a follower. The seatback has the other one of a guide member and follower. The guide member has a guideway and the follower engaging the guideway of the guide member such that upon impact to the vehicle, forward inertia of the headrest will cause the follower to engage the guideway in such a manner to cause the headrest to move in a manner to support the head of an occupant irrespective of whether occupant is in contact with the seatback. 
     In a more specific embodiment, the engagement of the follower and the guideway of the guide member together with the forward inertia of the headrest cause the headrest to move in a first manner and a second manner so as to support the head of an occupant. 
     In another more specific embodiment, the vehicle seat and headrest arrangement further includes a damper connected between the headrest arrangement and the seatback so as to retard movement of the headrest after it has moved in a manner so as to support the head of an occupant. 
     In another more specific embodiment, the guideway member is a bushing having a cam configuration and the follower is a cam such that engagement of the cam and cam configuration together with the forward inertia of the headrest cause the headrest to move in a first manner and a second manner. 
     In another more specific embodiment, the guideway of the guide member has a first guideway wall and a second guideway wall and the follower has a first follower portion and a second follower portion which engage the first guideway wall and second guideway wall respectively to cause the headrest to move in a first manner and a second manners so as to support the head of an occupant. The second guideway wall may have a first contact portion and a second contact portion and the second follower portion may have a first surface portion and a second surface portion such that upon impact to the vehicle, the first surface portion slidingly engages the first contact portion while the first follower portion slidingly engages the first guideway wall so as to cause the headrest to move in a first manner before the second surface portion slidingly engages the second contact portion as first follower portion continues to slidingly engage the first guideway wall so as to cause the headrest to move in a second manner. The first and second contact portions and the first and second surface portions may have relatively curved surface configurations and the first guideway wall and first follower portion may have relatively flat configurations substantially parallel to each other and inclined so as to facilitate sliding between the first guideway wall and first follower portion and movement in the first manner. 
     In another more specific embodiment, the headrest arrangement includes a headrest extension having one of a guideway member and a follower. 
     In another more specific embodiment, the vehicle seat and headrest arrangement further includes a movement-allowing connector connected between the headrest arrangement and the seatback. 
     In another more specific embodiment, the vehicle seat and headrest arrangement further includes a biasing member operatively associated with the seatback and the headrest arrangement which tends to bias the headrest against movement in a manner so as to support the head of an occupant. 
     The vehicle seat and headrest arrangement for use with a seat having a seatback in a vehicle may also comprise a headrest arrangement including a headrest, the headrest arrangement having at least one impact target and at least one of a guide member and a follower. The seatback has the other at least one of a guide member and follower. The guide member has a guideway and the follower engaging the guideway of the guide member such that upon impact to the vehicle one of a rearward load by the occupant upon the impact target and the forward inertia of the headrest irrespective of whether occupant is in contact with the seatback will cause the follower to engage the guideway in such a manner to cause the headrest to move in a manner to support the head of an occupant. 
     In a more,specific embodiment, the follower engages the guideway of the guide member such that upon impact to the vehicle the headrest may be moved in a first manner and a second manner so as to support the head of an occupant by one of a rearward load by the occupant upon the impact target and the forward inertia of the headrest irrespective of whether occupant is in contact with the seatback. 
     In another more specific embodiment, the vehicle seat and headrest arrangement further includes a damper connected between the headrest arrangement and the seatback so as to retard movement of the headrest after it has moved so as to support the head of an occupant. 
     In another more specific embodiment, the guide member is a bushing having a cam configuration and the follower is a cam such that engagement of the cam and cam configuration together with the forward inertia of the headrest cause the headrest to move in a first manner and a second manner. 
     In another more specific embodiment, the guideway has a first guideway wall and a second guideway wall and the follower has a first follower portion and a second follower portion which engages the first guideway wall and second guideway wall respectively to cause the headrest to move in a first manner and a second manners so as to support the head of an occupant. The second guideway wall may have a first contact portion and a second contact portion and the second follower portion may have a first surface portion and a second surface portion such that upon impact to the vehicle, the first surface portion slidingly engages the first contact portion while the first follower portion slidingly engages the first guideway wall so as to cause the headrest to move in a first manner before the second surface portion slidingly engages the second contact portion as first follower portion continues to slidingly engage the first guideway wall so as to cause the headrest to move in a second manner. The first and second contact portions and the first and second surface portions may have relatively curved surface configurations and the first guideway wall and first follower portion may have relatively flat configurations substantially parallel to each other and inclined so as to facilitate sliding between the first guideway wall and first follower portion and movement in the first manner. 
     In another more specific embodiment, the vehicle seat and headrest arrangement further includes a movement-allowing connector connected between the headrest arrangement and the seatback. 
     In another more specific embodiment, the vehicle seat and headrest arrangement further includes a biasing member operatively associated with the seatback and the headrest arrangement which tends to bias the headrest against movement in a manner so as to support the head of an occupant. 
     The vehicle seat and headrest arrangement may also comprise a headrest arrangement including a headrest and a headrest extension, the headrest extension having at least one of a guide member and a follower and an impact target located below the at least one of a guide member and a follower. A seatback frame of the seatback has the other at least one of a guide member and follower, the guide member having a guideway and the follower slidingly engaging the guideway of the guide member such that upon impact to the vehicle one of a rearward load by the occupant upon the impact target and the forward inertia of the headrest irrespective of whether occupant is in contact with the seatback will cause the follower to be slidably guided by the guideway such that the headrest is moved in a first and second manner. 
     In another more specific embodiment, the vehicle seat and headrest arrangement further includes a movement-allowing connector connected between the headrest arrangement and the seatback and a biasing member operatively associated with the seatback and the headrest arrangement which tends to bias the headrest against movement in a manner so as to support the head of an occupant. 
     The vehicle seat and headrest arrangement further includes a damper connected between the headrest arrangement and the seatback so as to retard movement of the headrest after it has moved so as to support the head of an occupant. 
     In another more specific embodiment, the guide member is fixedly attached to the seatback frame and has a first guideway wall and a second guideway wall and the follower is fixedly attached to the headrest extension and has a first follower portion and a second follower portion which slidingly engage the first guideway wall and second guideway wall respectively. The second guideway wall may have first and second contact portions having relatively curved surface configurations, the second follower portion may have first and second surface portions having relatively curved surface configurations, and the first guideway wall and first follower portion may have relatively flat configurations substantially parallel to each other and inclined relative to the headrest extension such that upon impact to the vehicle, the first surface portion slidingly engages the first contact portion while the first follower portion slidingly engages the first guideway wall so as to cause the headrest to move in a first manner before the second surface portion slidingly engages the second contact portion as the first follower portion continues to slidingly engage the first guideway wall so as to cause the headrest to move in a second manner. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a vehicle seat and headrest arrangement in accordance with the present invention; 
     FIG. 2 is a perspective view of a variable pivot mechanism for a headrest on a seatback frame in accordance with the present invention; 
     FIG. 3 is a cross-sectional view of a variable pivot mechanism for the headrest of FIG. 2 taken along lines  3 — 3 ; 
     FIG. 4 is a side view of movement of the headrest upon impact in accordance with the present invention; 
     FIG. 5 is a perspective view of another embodiment of the variable pivot mechanism in accordance with the present invention; 
     FIG. 6 is a cross-sectional view of the embodiment in FIG. 4 taken along lines  6 — 6 ; 
     FIG. 7 is a flow chart of one method of providing head support with a movable headrest of a vehicle seat to a vehicle occupant during rebound from a front impact of the vehicle. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S) 
     FIG. 1 illustrates a vehicle seat and headrest arrangement  10  having seat bottom  11  with fore end  11   a  and aft end  11   b,  seatback  12  with seatback frame  13  joined to seat bottom  11  adjacent aft end  11   b,  and headrest arrangement  14  pivotally and slidably attached to seatback frame  13 . Headrest arrangement  14  includes moveable headrest  22  which, in this and in most typical embodiments, is cushioned. As will be described in greater detail below, headrest  22  moves variably upon vehicle impact. In the embodiment shown, such variable movement occurs in first and second manners wherein the first and second manners relate to first and second forward velocities respectively, those being the velocities of the headrest  22  forward toward the occupant or the front of the vehicle, and first and second trajectories respectively, those being the trajectories or paths of headrest  22 . Such variable movement could be along any suitable combination of trajectories and velocities. As long as at least one of the first forward velocity and first trajectory is different than one of a second forward velocity and second trajectory, movement in first and second manners, variable movement, has been achieved. However, as will be explained in more detail, in the event of a vehicle impact, it is preferable that the headrest move in a first manner so as to more quickly lessen the gap between the head of an occupant and the headrest  22  and move in a second manner so as to decrease the forward velocity and provide support upon contact with the occupant&#39;s head. 
     As will be also described in greater detail below, headrest  22  is guidedly or cammingly moved from the normal position to the actuated position upon impact and irrespective of, or prior to, the occupant being in contact with the seatback  12 . 
     FIG. 2 depicts headrest arrangement  14  movable with respect to seatback frame  13 . As shown, seatback frame  13  includes upper cross member  16  having ends  17 , each of which have a side member  18  integrally attached thereto and extending downwardly therefrom. Lower cross member  20  extends across seatback frame  13  to connect side members  18 . Lower cross member  20  may be attached to side members  18  by any suitable means, such as by bolts (not shown). 
     In this embodiment, the upper cross member  16  includes at least one guide member, in this embodiment bushings  21 . Such bushings may be attached to the cross member  16  or formed within the cross member  16 . While not shown, the guide members could also be connected to any part of the seatback frame. Furthermore, the guide members, such as the bushings  21  shown, may be fixedly, rotatably, or otherwise movably connected to seatback frame  13  by any suitable means. In this embodiment, bushings  21  are welded to upper cross member  16 . 
     As shown, headrest arrangement  14  includes headrest  22  having cushion frame  23 , headrest extension  24  extending downwardly therefrom, and impact target  26  to which extension  24  extends. The impact target  26  may have any suitable configuration or shape and may be made from any suitable material. In this embodiment, impact target  26  is disposed within seatback frame  13  and between side members  18 . The headrest  22  and impact target  26  are operatively associated as the headrest arrangement  14  moves variably with respect to the seat back frame  13 . As described in greater detail below, headrest arrangement  14  cooperates with seatback frame  13  to define shifting axes about which headrest arrangement  14  pivots. 
     As depicted in FIGS. 2 and 3, headrest extension  24  extends downwardly from cushion frame  23  through each guide member, in this embodiment bushings  21 , to an impact target  26 . Each guide member defines a guideway, in this embodiment guideway  25 . As shown, the headrest extension  24  in this embodiment constitutes two posts. However, a single post or any other suitable extension may be utilized. Likewise, a single guide member or any other suitable number of guide members may be utilized. Furthermore, while not shown the headrest extension of the headrest arrangement could include or constitute an upper portion or part of the seatback frame such that the upper portion or part could move variably. 
     As shown in this embodiment, one or more movement-allowing connectors  28 , such as links or hinges shown, may be used to pivotally or otherwise suitably attach impact target  26  to side members  18 . Such movement-allowing connectors  28  may be connected at each end to the impact target  26  and side member  18  respectively, in a pivotal, fixed, or otherwise suitable manner. More specifically, as shown in the embodiment depicted, each of the movement-allowing connectors  28  may be pivotally attached to the seatback frame  13  on pivot axis A generally perpendicular to the fore and aft direction. The other end of the movement-allowing connector may also be pivotally attached to the impact target  26 . As shown in FIGS. 2 and 4, the pivot axis A is offset relative to the impact target  26  such that a rearward force applied to the impact target  26  will tend to cause the movement-allowing connector  28  to pivot about the pivot axis A and the impact target to move in a generally rearward and upward direction. Of course, any other suitable movement-allowing connector  28  between the impact target  26  and the side member  18 , or between any suitable portion of the headrest arrangement  14  and the seatback frame  13 , could be used, such as multiple linkages for example, such that the impact target pivots about a fixed or variable (instantaneous) pivot axis. 
     Rearward loading of impact target  26  will cause headrest  22  to pivot toward the head of the occupant. Preferably, a suitable biasing member is operatively associated with the seatback frame  13  and headrest arrangement  14  in order to bias headrest arrangement  14  against such movement. As shown in this embodiment, such biasing member may consist of springs  29  attached between the lower cross member  20  and each link  28 . However, such biasing member may be operatively associated with or between the seatback frame  13  and headrest arrangement  14  in any suitable manner. Furthermore, while in this embodiment, spring  29  is a metallic coil, any suitable biasing member, such as an elastic tube, may be used. 
     As shown in this embodiment, a damper  27  may be connected to the impact target  26  and the seatback frame  13  for retarding rearward movement of headrest  22  as will be described in further detail. The damper  27  may be any suitable dampening or biasing material, device, or mechanism which lengthens, expands, or extends under a relatively light or suitable tensile load while suitably retarding, which may include preventing, movement under a compressive load. If one or more dampers  27  are employed, they may be disposed at any suitable location , and be connected between the seatback frame  13  or any other suitable component, and the impact target  26 , the headrest extension  24 , the headrest  22 , or any other suitable component in any suitable manner and at any suitable location in order to retard rearward movement of headrest  22 . For example, and without limitation, dampers  27  may be disposed between the lower cross member  20  and links  28 . 
     As shown in FIG. 3, in one embodiment of the present invention the guide member, in this embodiment the bushing  21 , includes a guideway  25 , which in this embodiment includes a cam configuration  31  having a first movement portion and a second movement portion, the operation of which is described in paragraphs below. While the guideway  25  in this embodiment has a first movement portion and a second movement portion, the guideway  25  is not limited to such a configuration but may have any suitable configuration. Furthermore, the guide member could utilize a slot or any other suitable configuration in guiding the follower as will be explained. 
     The cam configuration  31  in this embodiment includes a first guideway wall  32  and a second guideway wall  34 . As shown, second guideway wall  34  may have first contact portion  36  and second contact portion  38  formed vertically adjacent each other and integrally connected. In this embodiment the first guideway wall  32  has a relatively flat surface configuration inclined at an angle relative to the adjacent portion of the extension  24 . The first contact portion  36  and second contact portion  38  of the second guideway wall  34  both have relatively curved or arcuate surface configurations. Of course, any other suitable configuration of the first and second guideway walls  32 ,  34  may be used. Likewise, any suitable configuration of first and second contact portions  36 ,  38 , may be used 
     As illustrated in FIG. 3, the follower  39 , in this embodiment a cam  40 , may be disposed on extension  24 . Cam  40  may be disposed on extension  24  by any suitable means such as by welding or molding. The follower  39 , in this embodiment cam  40 , cooperates with the guideway  25  of the guide member, in this embodiment the bushing  21  having a cam configuration  31  with a first guideway wall  32  and second guideway wall  34 . While the follower in this embodiment is a cam, any other suitable follower configuration could be utilized, such as a projection projecting laterally from the extension  24  and engaging a slot or other suitable configuration of the guide member. Furthermore, while in this embodiment the follower is connected to the extension  24  and the guide member is connected to the seatback frame  13 , the follower could also be connected to the seatback frame  13  and the guide member could be connected to the extension  24 . 
     The follower, in this embodiment the cam  40 , has a first follower portion  41  and a second follower portion  43 . The second follower portion  43  includes a first surface portion  42  and a second surface portion  44  formed vertically adjacent each other and integrally connected. As shown in this embodiment, first and second surface portions  42 ,  44  may have similar arcuate or curved surface configurations. However, any other suitable configurations of the first and second surface portions  42 , 44  may be used and the configurations of the first and second surface portions may be mirror images of each other or different. In the embodiment shown, while extending the first surface portion  42  initially at approximately 30 degrees from the extension  24  to cooperate with the first contact portion  36  of the second passageway wall  34  has been found to be satisfactory, any suitable angle may be used. 
     As shown, and as discussed in further detail below, in this embodiment the first and second surface portions  42 ,  44  slidably contact first and second contact portions  36 ,  38 , respectively, to provide improved head support to the occupant upon vehicle impact. Of course, first surface portion  42  may also slidably contact second contact portion  38  and second surface portion  44  may also slidably contact first contact portion  36  without departing from the spirit or scope of the present invention. 
     As shown in FIGS. 1-4, in this embodiment the first follower portion  41  extends from extension  24  opposite first and second surface portions  42 ,  44 , and has a first follower end  47  to slidably contact the first guideway wall  32 . While the first follower end  47  of the first follower portion  41  has been shown in this embodiment to have a relatively flat surface configuration, inclined relative to the extension  24  so as to slidably cooperate with the first passageway wall, any other suitable configuration may be used. During normal use of the vehicle seat and headrest arrangement  10 , the first follower portion  41  serves to prevent the extension  24  from shifting back and forth, and to provide a substantially snug fit within the guide member, in this embodiment the bushing  21 . 
     However, upon vehicle impact, first and second follower portions  41 ,  43  and first and second guideway walls  32 ,  34 , are configured to cooperate together to move headrest  22  in first and second manners, e.g., first and second forward velocities and first and second trajectories of headrest  22 . More specifically, upon impact of the vehicle, an occupant of the vehicle provides rearward load on impact target  26 . In turn, connectors  28  pivot about axis A and the impact target  26  moves in a generally rearward and upward direction. As a result, extension  24  slides upwardly through the guideway  25  of the guide member, in this embodiment the bushing  21 , and first surface portion  42  slides along first contact portion  36 , and first follower portion  41  slides along first guideway wall  32 . This movement, movement in the first manner, defines the first forward velocity and first trajectory of headrest  22  toward and relative to the occupant&#39;s head. This movement also defines the first movement portion. More specifically, this movement in the first manner causes the headrest  22  of the headrest arrangement  14  to pivot with respect to the seatback frame  13  along a first trajectory about and above a constant or shifting axis. The first trajectory and the force of the impact define a first forward velocity of the headrest  22  toward the head of the seat occupant. 
     Then, the second surface portion  44  slides along second contact portion  38 , as follower portion  41  continues to slide along and past first guideway wall  32 . This movement, movement in the second manner, defines the second velocity and second trajectory of headrest  22  toward and relative to the occupant&#39;s head. This movement also defines the second movement portion. More specifically, this movement in the second manner causes the headrest  22  of the headrest arrangement  10  to pivot with respect to the seatback frame  13  along a second trajectory about and above a constant or shifting axis. The second trajectory and the force of the impact define a second forward velocity of the headrest  22  toward the head of the seat occupant. 
     Each of the constant or shifting axes is the pivot axis, also called the instant center axis, instantaneous pivot axis, or instantaneous axis, about which the headrest  22  pivots at any given time during movement along a particular trajectory. 
     In the embodiments shown, the pivot axis, also called the instant center axis, instantaneous pivot axis, or instantaneous axis, about which the headrest portion pivots shifts throughout the trajectories of the headrest  22  during a rearward loading of the impact target. Shifting the instantaneous axis downwardly allows the headrest  22  to move in a more forwardly direction toward the occupant&#39;s head upon a rearward force to the impact target. Preferably, the vehicle seat and headrest arrangement is such that the instantaneous axis shifts within a relatively lower range of positions during camming between the first surface portion  42  and the first contact portion  36 . The resulting trajectory is such that the headrest  22  will move in a direction more directed toward the occupant&#39;s head during the course of the first trajectory. Shifting the instantaneous axis upwardly, within a relatively higher range of positions, after the movement in the first manner has been accomplished, allows the headrest  22  to move more upwardly, and support the occupant&#39;s head, during movement in the second manner. In the embodiments shown, the cam is formed such that the instantaneous axis shifts upwardly upon contact of the second surface portion with the second contact portion  38 . 
     In summary, upon vehicle impact, the headrest  22  moves forwardly and upwardly in first and second manners, along first and the second trajectories, and at first and second forward velocities. The greater the crash acceleration, the greater the velocity of headrest  22  in the first and second manners. 
     Although both trajectories provide for both forward and upward movement of the headrest  22 , the first trajectory allows the headrest  22  to move more forwardly and the second trajectory allows the headrest  22  to move more upwardly. The first forward velocity is preferably greater than the second forward velocity. The first forward velocity allows the headrest  22  to quickly move a predetermined distance to lessen the gap between the occupant&#39;s head and the headrest  22 . The second velocity allows the headrest  22  to further lessen the gap and to slow down or stop relative to the seat occupant&#39;s head for supporting the occupant&#39;s head upon contact. 
     In this particular embodiment, headrest  22  moves in a forward and upward direction for a predetermined distance toward the occupant&#39;s head in order to lessen the gap therebetween. More specifically, during movement of the headrest  22  in the first and second trajectories, the headrest  22  is configured to move forward a predetermined distance. While a distance range between 2 and 25 centimeters may be suitable, any suitable distance may be used and will be dependent, at least in part, on the interior design parameters of the particular vehicle. 
     In the particular embodiment shown, due to the configuration of the first surface portion  42  and the first contact portion  36 , the headrest  22  moves more forwardly than upwardly to define the first trajectory, providing the first forward velocity. Due to the configuration of the second surface portion  44  and the second contact portion  38 , the headrest  22  moves more upwardly than forwardly to define the second trajectory, providing the second forward velocity. Thus, in this embodiment, the first forward velocity is greater then the second forward velocity in the direction toward the head of the vehicle occupant. Accordingly, surface portions  44 ,  46  and contact portions  36 ,  38  are designed to reduce headrest  22  movement directly toward the occupant&#39;s head after movement in the first manner. 
     In normal vehicle seat and headrest arrangements, during the initial stages of an impact, the occupant&#39;s torso is in contact with the seatback while the occupant&#39;s head is several inches forward of the headrest  22 . This condition is consistent with the body being reclined at about 20-25 degrees from vertical with the neck being approximately vertical. In contrast, the seat is usually at a reclined angle of approximately 20-25 degrees from vertical, with the headrest either following the inclination of the seatback or curving slightly forward. In any event, for seating comfort, the head is usually not in contact with the headrest while driving. 
     As the occupant loads the seatback in an impact, force builds up behind the torso and buttocks of the seat occupant as the head, neck, torso, and buttocks move in unison. Typically, there is a greater compression in the torso and buttocks regions of the seat, with a gradual reduction up to the shoulder level as the body remains upright. The more severe the crash, the greater the compression of the occupant into the seatback. As this action is occurring, the initial load of the occupant tends to deflect the seatback rearwardly. The amount of deflection is related to the bending stiffness of the seatback. The seatback may possibly deflect under the torso load prior to the head and neck of the occupant contacting the headrest. The current invention reduces this “whiplash” effect by bringing the headrest forward into a head supporting position. 
     In a front impact of the vehicle, the occupant initially moves forward relative to the vehicle seatback. Upon contact with a front interior panel or a deployed airbag from the front panel of the vehicle, the occupant experiences rebound movement in a rearward direction. As the occupant loads the seatback in a rebound during the front impact, force builds up behind the torso and buttocks of the occupant. Like a rear impact, depending upon the compliance of the seatback, the occupant compresses into the cushion as the head, neck, and torso move in unison. In this situation, like in a rear impact situation, there is a greater compression in the buttocks region than in the shoulder region of the occupant. Thus, there is a potential that the seatback deflects under the torso load prior to the head and neck of the occupant contacting the headrest, resulting in a gap between the head and the headrest in a front crash situation and the potential for a “whiplash” effect. 
     With the present invention and in the event of a front impact, the sudden substantial deceleration in forward velocity will cause the headrest  22  to move forward from the normal position, independent of the occupant contacting the seatback  12  or impact plate  26 . Upon front impact of the vehicle, when the occupant is initially thrown forward, the forward inertia of the headrest  22  will cause the follower  39  to follow the guideway  25  such that the first follower end  47  will slidably engage the first guideway wall  32  while the first surface portion  42  slidably engages the first contact portion  36 . This allows headrest  22  to move at least in the first manner, at the first forward velocity and along the first trajectory. Then, similar to a rear impact situation described above, the second surface portion  44  will slidably engage the second contact portion  38 . This allows the headrest  22  to move in the second manner, at the second forward velocity and along the second trajectory. As in a rear impact situation, the headrest  22  will then have moved in a forward direction for a predetermined distance toward the occupant&#39;s head in order to lessen the gap between the headrest and the occupant&#39;s head. The damper  27  serves to retard, which may include preventing, movement of the headrest back from the actuated or forward position back to the non-actuated or normal position before and after contact between the occupant&#39;s head and the headrest. 
     FIGS. 5 and 6 depict another embodiment which operates similar to the embodiment described above. This embodiment includes components similar to components of vehicle seat and headrest arrangement  10  above. Similar components will be referred to by the same reference characters used to identify like components in the first embodiment. However, in this embodiment, a different guide member, bushing  121 , is disposed on seatback frame  113  and includes a first guideway wall  132  and second guideway wall  134  having a pair of first and second contact portions  136 ,  138 . A follower, in this embodiment a cam  140 , is disposed on extension  124  and includes a pair of first and second surface portions  142 ,  144  formed to cooperate with the pair of first and second contact portions  136 ,  138 , respectively. As shown, the first guideway wall  132  includes a planar surface upon which a first follower portion  141  slides during movement of the headrest arrangement  114 . Similar to the embodiment described above, the first and second surface portions  142 ,  144  slidably contact the first and second contact portions  136 ,  138 , respectively, to define first and second forward velocities and first and second trajectories of the headrest  22  during vehicle impact and to accordingly provide improved head support to the occupant upon vehicle impact. 
     While not shown, as a further alternative example embodiment, the invention may be constructed such that the impact target  26  is not connected to the side member  18 . In such an embodiment, the impact target could be supported in the non-impact position via a guide member and follower for example. 
     It is to be noted that the embodiments described above may be made by any conventional means using any conventional materials known in the vehicle seating art. 
     FIG. 7 depicts one method  310  of supporting the head of a vehicle occupant in a vehicle seat having a seatback and a headrest arrangement movable with respect to the seatback. Method  310  includes providing the headrest adapted to be spaced from the head of the occupant in the seat to define a normal or rest position of the headrest arrangement in block  312 . In the normal position, an instant center of the headrest arrangement is designed or configured substantially lower relative to the center of gravity of the headrest arrangement. Thus, upon front impact of the vehicle in block  314 , the headrest arrangement independently moves from the normal position toward contact with the occupant&#39;s head in a first manner and a second manner to define an actuated position of the headrest, irrespective of the occupant being in contact with the seatback of the vehicle seat. The configuration of the guideway and the follower allows the headrest to independently move forward to support the occupant&#39;s head upon a front impact in a first manner and second manner. As described above, the first manner involves the headrest moving along a first trajectory at a first forward velocity. The second manner involves the headrest moving along a second trajectory at a second forward velocity. In block  316 , the method includes retarding movement of the headrest arrangement back from the actuated position to the normal position, before and after contact with the head. The damper retards such movement. This provides improved support to the occupant&#39;s head from rebound toward the seatback in the case of a front impact. 
     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.