Head restraint follower

Reclining seat mounted on a foundation through first and second slides. The seat cushion is mounted on the first slide, and the seat back is mounted on the second slide. The slides, the seat cushion and the seat back are arranged to move together as one unit to have the seat recline. A head restraint is mounted at a top side of the seat back to follow and move with the back during movement of the back. The second slide has a non-linear curved shape to rotate the head restraint when the seat back moves. The curved shape rotates the headrest in a backward and downward direction when the seat back moves downward and the seat cushion moves forward, and vice versa. From the different seat positions, the head restraint follows the motion of the occupant as they move to the different seat positions.

FIELD OF THE INVENTION

The present invention relates to a head restraint for a seat, and in particular for a head restraint that follows a seat back, as the seat is movable into upright and reclining positions.

BACKGROUND OF THE INVENTION

It is often desirable for a seat to have a head restraint, especially when the seat is mounted in a motor vehicle that is subject to relatively large accelerations. The head restraint can prevent the head of the occupant from being thrown backwards and possibly causing injury to the occupant. Also the head restraint can provide resting support to the head of the occupant providing a more comfortable sitting experience. To further increase the comfort of the occupant, it is often desirable to have the seat recline, and to have the parts of the seat, especially to have the seat formed of very cushioning material.

Because of the amount of cushioning on the seat back, is often difficult to mount a head restraint directly to a seat back, especially to provide sufficient support to the head during accelerations of the seat/vehicle. Because of the reclining arrangements, mounting a head restraint directly to a foundation, is often disadvantageous, in that the head restraint will not follow the reclining seat and not be in an optimal position when the seat is reclined. Even if the head restraint is directly mounted to the seat back, the reclining arrangements often still do not position the head restraint in optimal position for the different reclined positions of the seat.

SUMMARY OF THE INVENTION

A reclining seat is mounted on a foundation through at least first and second slides which are spaced from each other. The seat has a seat cushion which has a generally horizontal top surface for providing mostly vertical support for a lower portion of the occupant/passenger. The seat cushion has a front side and a back side defining a forward/backward direction. The front side of the seat cushion being the side closest to the lower legs of the occupant/passenger, and the back side of the seat cushion being the side closest to the back of the occupant/passenger. The seat cushion is mounted on the first slide, and through the first slide, the seat cushion is slidably mountable on the foundation in the forward/backward direction.

The first slide can be a single unit movably connecting the seat cushion to the foundation. Alternatively, the first slide can be divided into two units positioned on the right and left, or lateral, sides of the seat cushion. Generally when the first slide is divided into two units, each unit is formed of upper and lower rails which slide relative to each other in the forward/backward direction.

The seat has a seat back with a generally vertical surface for providing horizontal support to an upper portion of the occupant/passenger. The seat back has a bottom side and a top side defining a lengthwise direction of the seat back, and the lengthwise direction extends back and forth between the top side and the bottom side of the seat back.

The bottom side of the seat back can be pivotally connected to the seat cushion, either directly to the back side of the seat cushion, or through a link arm to another portion of the seat cushion. The seat back is mounted on the second slide through which the seat back is slidably mountable on the foundation in generally the lengthwise direction. The slides, the seat cushion and the seat back are arranged to have the seat cushion and the seat back move together as one unit while the seat cushion generally moves in the forward/backward direction and the seat back moves in the lengthwise direction. A head restraint is mounted at the top side of the seat back to follow and move with the seat back during movement of the seat back in the lengthwise direction.

The second slide is mounted so that the seat back can follow the seat cushion as the seat cushion moves forward and back on the first slide. As the seat back follows the seat cushion during sliding of the seat cushion from back to front, the second slide slides the seat back in a downward and forward motion. This is done, to allow the occupant/passenger to be in more of a horizontal/resting position than in an upright position when the seat cushion is in the most rearward position. Very often, especially during long vehicle trips, the occupant/passenger prefers to change his or her seating position between a more upright position to a more horizontal/resting position, or to any of the practically infinite positions in between the upright and horizontal/resting position.

In order to help facilitate moving the occupant/passenger from the upright position to the resting position, the sliding motion of the seat cushion preferably has a vertical component. This can be accomplished by having the first slide mounted on an angle with respect to the horizontal. The first slide is then to be mounted so that when the slide is in the most forward position, the seat is in a higher position than when the slide is in the rearmost position. By moving the seat cushion in an upward direction as the seat cushion slides forward, the seat back does not need to move as far down in order to place the occupant/passenger in the horizontal/resting position. This reduces the amount of movement required between the upright and horizontal/resting position, and also reduces the amount of structure needed to perform the corresponding movement.

The second slide has a non-linear curved shape to rotate the head restraint when the seat back moves in the lengthwise direction. The curved shape rotates the headrest in a backward and downward direction when the seat back moves downward and the seat cushion moves forward, from the upright position to the horizontal/resting position. Likewise, the curved shape rotates the headrest in a forward and upward direction when the seat back moves upward and the seat cushion moves backward, from the horizontal/resting position to the upright position. From these different seat positions, and all the positions inbetween, the head restraint follows the motion of the occupant in the seat as they move to the different seat positions.

The second slide includes a first rail/track and a second rail/track slidably connected to each other along a curved path. The seat back is pivotally connected to the first rail to increase the amount that the seat back can rotate between the upright and rest positions, beyond just the rotation provided by the curved path. The second rail is to be mounted on the foundation. An attachment bracket connects the head restraint to the first rail of the second slide. The attachment bracket has a first end arranged below the top side of the seat back, and fixed to the first rail, preferably to be non-rotational. The attachment bracket has a second end arranged above the top side of the seat back and connected to the head restraint.

This arrangement allows the head restraint to move with the occupant as he/she moves to any of the practically infinite positions between the upright and rest position in the seat system. This type of seat that moves between such positions is often called a recliner/slouch seat system, and is a sliding system that moves with the natural kinematics of the occupant as he/she slouches. One advantage of this seat slide system is that it allows the occupant to recline (slouch) in a fluid motion that does not cause any shirt shear (back of shirt pulled from pants while reclining), or sheer in the head area of the occupant/passenger.

For this to happen, the head restraint and seat back must follow the seat cushion without the head restraint, seat cushion and the seat back changing positions relative to the occupant/passenger. The head restraint, seat cushion and the seat back must significantly follow the occupant/passenger through all of the practically infinite positions between the upright and resting position in order to avoid discomfort of the occupant/passenger as the occupant/passenger moves through all the positions between the upright position and the resting position, and vice versa. This slide system of the present invention offers infinite adjustment while still being strong enough to support an occupant/passenger in a motor vehicle, and while still being light enough and small enough to be practically incorporated into a motor vehicle.

A linear locking mechanism is provided next to each of the first and second slides, so that each slide can be locked into the exact position that the occupant desires. A possible linear locking mechanism is manufactured by Porter Systems LLC having an address at 28700 Cabot Drive, Suite 800 Novi, Mich. 48377. This locking mechanism offers infinite adjustment because it uses the forces created from two torsional springs working in tandem with two bushings to lock on a solid shaft. These linear locking devices are described further in U.S. Pat. Nos. 5,157,826, 5,794,470, 8,038,220, 5,794,470, 5,441,129, 5,219,045, 5,157,826, 5,15,0771, 4,880,084, 4,577,730, 4,457,406, 4,425,987, 4,411,339, 3,874,480, 5,568,843, which are herein incorporated by reference. Other linear and rotational locking mechanism could be used.

The design offers low release and sliding efforts with infinite adjustment. The head restraint, and its connection to the slide offers additional kinematics that allow the head restraint to follow the motion of the occupant during recline (slouch). This provides improved comfort and satisfaction for the occupant since the head restraint follows occupant motion, maintains smooth, low sliding efforts and low release efforts, maintains infinite adjustment, and maintains low cost due to simplified manufacturing and assembly process (no complex linkage systems or additional locking mechanisms added to get head restraint to follow seat back motion).

The head restraint can be made with movable portions to adjust the position of the head and to control lateral movement as disclosed in PCT Patent Publication WO 2015 175 655 A1, and Applicant's copending PCT Patent Application PCT/US17/43620 corresponding to U.S. Provisional Application 62/377,093, all of which are incorporated herein by reference in their entirety.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the drawings in particular,FIG. 1shows a seat10mounted on a foundation12. The seat10includes a seat cushion14and a seat back16. The seat back16is pivotally connected to the seat base14. This pivotal connection can be a connection through a link arm20, or the seat back16can be pivotally connected to the seat base14through a connection such as disclosed in U.S. Pat. No. 9,346,376, which is hereby incorporated by reference in its entirety.

The seat10can be arranged to be a type of seat as indicated by the term “slouch seat”. Such a slouch seat has the seat cushion14, the seat back16, the foundation12, and structure connecting all of these parts to form a seat10that moves from an upright position as shown inFIG. 4, to a more horizontal/rest position as shown inFIG. 5. The degree to which the slouch seat becomes horizontal, depends on the application where the seat will be mounted. In applications where the seat has sufficient legroom, the slouch seat can become very horizontal. In other applications, such as economy class or in the driver's seat of a vehicle, less movement into a horizontal position is desired.

The arrangement of such a slouch seat is described in Applicant's copending PCT patent applications PCT/US17/29073 (corresponding to U.S. Provisional Patent Application 62/329,551), PCT/US17/41151 (corresponding to U.S. Provisional Patent Application 62/362,241), and PCT/US17/41105 (corresponding to U.S. Provisional Patent Application 62/367,903), all of which are incorporated herein by reference in their entirety.

A head restraint18is arranged above the seat back16to provide a support for the head of the occupant of the seat10. This support can be as minor as a place for the head to rest and provide comfort to the occupant/passenger. The support provided is often desired to be more significant, such as providing support to the head when the seat10undergoes large accelerations, especially in the forward direction, such as when the seat10is mounted in a vehicle.

Large forward accelerations of the vehicle push the seat against the occupant/passenger, and if sufficient support is not provided to the head of the occupant/passenger, then the head will be forced backward during the forward acceleration. In order to avoid/minimize injury to the occupant, the head restraint needs to provide the same support/force/push to the head that the rest of the seat applies to the body of the occupants/passenger.

The head restraint18can also have wings19which rotate about a centrally positioned vertical axis to provide lateral support to the head of the occupant, during lateral accelerations, such as during turning motions of the vehicle, and especially at high speed turning motions. The arrangement of the head restraint18, specifically with regard to the wings19is described in Applicant's copending PCT Patent Application PCT/US17/43620, which has been previously cited.

The seat10is overall a recliner type seat, and preferably where the reclining motion is formed by both the seat cushion14and the seat back16sliding in a front to back or lengthwise direction.FIGS. 3 through 5show the different positions of the slouch seat.FIG. 3shows the seat10in a position called a design position, a neutral position, and/or basic position. This position is chosen to be somewhere between a fully upright position, and a fully reclined/rest position. The fully reclined/rest position depending of course on the application for which the seat is to be applied.

The seat base14is slidably connected to the foundation12through a first slide22. The seat back16is a slidably connected to the foundation12through a second slide24. The seat back16is connected to the second slide24by a pivot connection36. This allows the seat back16to better follow the seat cushion14in the movement between the fully upright position and the reclined position, and keep the parts of the seat10in a relatively fixed contact with the respective parts of the occupant/passenger during movement between the positions. Further details regarding the structure of the first and second slide22,24and their connections between the seat base14, seat back16, and foundation12are disclosed in Applicant's co-pending U.S. patent application Ser. No. 62/362,241 which has been previously cited.

FIG. 4shows the seat10in the full upright position. The seat base14has been moved rearward, or to the right inFIG. 4, relative toFIG. 3. The seat back16has moved higher, and in a slightly counter clockwise direction inFIG. 4, relative toFIG. 3. Depending on the occupant/passenger, this position may be more desirable than the neutral or design position shown inFIG. 3.FIG. 5shows the seat10in the full recline position. The seat base14has been moved to its full extent forward, or to the left inFIG. 5, relative toFIGS. 3 and 4. Likewise, the seat back16has been moved to its lowest position relative toFIGS. 3 and 4.

It is desirable for the head restraint18to move with the rest of the seat10so that the head restraint18can provide the support to the head for both comfort reasons, and to prevent injury during large accelerations, both forward and lateral, at all the positions of the seat10between the fully upright position as shown inFIG. 4, and the fully reclined position, for example as shown inFIG. 5.

For many reasons, it is sometimes disadvantageous for the head restraint18to be directly connected to the seat back16, such as being mounted directly to the top21of the seat back16. One reason being that the seats for vehicles are often desired to be light weight to increase the fuel economy of the vehicle, and the seats are desired to be made to take up as little space as possible, in order to provide room for more desirable uses for the space. As such, the top21of the seat back16is preferably designed to just provide support for the upper back of the occupant/passenger. This then does not provide sufficient support on the seat back16for a head restraint18, especially when significant support is needed for the safety of the head of the occupant during large accelerations of the vehicle in which the seat10is mounted.

The head restraint18is therefore mounted in the present invention more directly to the second slide24, than to the seat back16. This is preferably done through an attachment bracket30. In a particular type of slouch seat, the seat base14is connected to the seat back16by a link arm20. The link arm20is pivotally connected to the seat back16through a pivot connection36, which also preferably connects the seat back16to the second slide24. The link arm20is connected to the seat base14through a pivot point32.

The seat10has lateral sides which correspond to the right and left sides of the occupant/passenger. These lateral sides are arranged perpendicularly spaced from the forward/backward direction and the lengthwise direction. The second slide24is preferably arranged as a single slide in the lateral center or lateral middle area of the seat back16. In the preferred embodiment, there is a link arm20arranged on each of the right and left, or lateral sides, of the seat10.

The first slide22preferably is formed from two subassemblies23, where only the left subassembly23is visible in the drawings. Each subassembly23is arranged at the lateral sides of the seat cushion14. The lateral sides of the seat cushion14corresponding to the right and left sides of the occupant/passenger. The two subassemblies23of the first slide22being arranged closer to the lateral sides and than to a lateral center or lateral middle of the seat cushion14. Each of the link arms20being connected to a different one of the two subassemblies23of the first slide22.

Because of the pivoting connections36and32between the seat back16, and the seat cushion14, especially through the link arm20, and the pivoting connection36between the seat back16, link arm20and the second slide24, a direct straight sliding of the head restraint18to the slide24will not necessarily always have the head restraint18desirably follow the movement of the seat back16. By curving the second slide24so that the second slide24follows a curved, nonlinear, path, the head restraint18can more desirably follow the seat back16during movements of the seat10between the full recline and full upright positions.

As shown inFIGS. 6-8, the second slide24has a first rail/track26which is slidably connected to a second rail/track28. In the embodiment ofFIGS. 6-8, the first rail26slides inside the second rail28, however this could be reversed, and other slidable connections between the first rail26and the second rail28are possible. For example PCT patent application PCT/US17/41105, previously cited, discloses a type of slide. The first rail26and the second rail28are connected to slide along a curved path similar to the arrows34shown inFIGS. 6-8.

The seat back16is connected to the first rail26at the pivoting connection36, which is preferably also a pivotal connection for the link arm20. The head restraint18is connected to the first rail26through an attachment bracket30having an elongated shape. One end38of the attachment bracket30is connected to the first rail26, and another axially opposite end is connected to the head restraint18. The attachment bracket30has a sufficient axial length in order to position the entire head restraint18above the top21of the seat back16, and in a position to support the head of the occupant/passenger. The attachment bracket30can have adjustment structure to just the axial length of the attachment bracket30in order to adjust the position of the head restraint18to provide comfort and support to occupant/passengers of different sizes. In the alternative, the head restraint18can be adjustable in the generally vertical direction by means of its own structure, which is separate from the attachment bracket30. Such structure is disclosed in PCT/US17/43620, which has been previously cited.

The second rail28of second slide24is mounted on the foundation12. The one end38of the attachment bracket30is fixed to the first rail26at a bracket point that is spaced from the connection pivot point36along a lengthwise direction of the first rail26. The spacing is preferably chosen so that the connection pivot point36is at one axial end of the second rail28, and the one end38of the attachment bracket30is at another axially opposite end of the second rail28. This spreads the load of the headrest18and the seat back16across the entire length of the second rail28. This also places the attachment bracket30and the head restraint18at a different position on the curved path of the second slide24. In particular, the attachment bracket30will always be in a more vertical direction of the second slide24, which puts the headrest18in a more favorable position to support the occupant/passenger.

In the alternative, the end38of the attachment bracket30could be directly connected to the connection pivot point36and the attachment bracket30could have a curved shape to properly position the head restraint18to support the head of the occupant/passenger. Still furthermore, the attachment bracket30could both have a curved shape, and the end38spaced from the connection pivot point36, so that the combination properly positions the head restraint18in all positions of the seat10between the full upright position, and the recline position.

The connections and the curved path are arranged to have the head restraint18rotate when the seat back16moves in the lengthwise direction. The curved path rotates the headrest18in a backward and downward direction when the seat back16moves downward and the seat cushion14moves forward. The curved path/shape rotates the headrest18in a forward and upward direction when the seat back16moves upward and the seat cushion14moves backward. The degree of curvature, the spacing between the connection pivot point36and the one end38of the attachment bracket30, and optionally any curve in the attachment bracket30are chosen to keep the head restraint18and the seat back16always in fixed contact with their respective parts of the occupant, and to avoid having the head restraint18, or the seat back16slide against the occupant as the seat moves between the full upright position and the recline position.

This is one method for linking a head restraint18to the motion of the seat10. There could be other methods or additional mechanisms/links added to the seat10to get the head restraint18to follow the motion of the occupant as he/she changes positions

LIST OF REFERENCE CHARACTERS

21seat back top

23subassembly of first slide

38one end of attachment bracket

40another end of attachment bracket