| JP2699269 | HEAD REST |
| JP2005067329 | HEADREST AUTOMATIC STORAGE ADJUSTING DEVICE |
| WO/2006/046719 | CUSHION PLATE WITH PRESSURE REGULATING MECHANISM OF VEHICLE SEAT |
HSU, Chi-Fan (45463 Irvine Drive, Novi, MI, 48374, US)
| WHAT IS CLAIMED IS: 1 . A head restraint for a vehicle seat comprising: a connecting member; an insert secured to the connecting member, wherein the insert is formed using a natural oil-based polymer; and an inner cushion layer covering the insert and a portion of the connecting member. 2. The head restraint of claim 1 wherein the natural oil-based polymer is an open cell, polyurethane foam having a plant oil based polyol portion. 3. The head restraint of claim 1 , wherein the natural oil-based polymer is mixed with a rigid or semi-rigid polyurethane polymer to form the insert. 4. The head restraint of claim 1 wherein the inner layer is formed from a flexible polyurethane polymer. 5. The head restraint of claim 1 wherein the insert formed using a natural oil-based polymer foam mixture that exhibits hardness properties at least that of an insert formed using a petroleum-based foam mixture. 6. A headrest for a vehicle seat comprising: an insert formed using a natural oil-based polymer, wherein the natural oil-based polymer is an open cell, polyurethane foam having a plant oil based polyol portion; and a cushion layer covering the insert to form the head rest. 7. The headrest of claim 6, wherein the natural oil-based polymer is mixed with a rigid or semi-rigid polyurethane polymer to form the insert. 8. The headrest of claim 6 wherein the inner layer is formed from a flexible polyurethane polymer. 9. The headrest of claim 6 wherein the insert is formed using a natural oil-based polymer foam mixture exhibits hardness properties at least that of an insert formed using a petroleum-based foam mixture. 10. The headrest of claim 6 further including an outer cover surrounding the inner cushion layer. 1 1 . A method of forming a head restraint for a vehicle seat, said method comprising the steps of: forming a connecting member; forming an insert using a natural oil-based polymer foam material; securing the insert to the connecting member; and molding an inner cushion layer covering the insert and a portion of the connecting member. 12. The method of claim 1 1 , further including the step of mixing the natural oil-based polymer with a rigid or semi-rigid polyurethane polymer to form the insert. 13. The method of claim 1 1 further including the step of using a flexible polyurethane polymer to form the inner cushion layer. 14. The method of claim 1 1 wherein the insert is formed using a natural oil-based polymer foam mixture exhibits hardness properties at least that of an insert formed using a petroleum-based foam mixture. 15. The method of claim 1 1 further including the step of forming an outer cover surrounding the inner cushion layer. 16. The method of claim 1 1 wherein the natural oil-based polymer is an open cell, polyurethane foam having a plant oil based polyol portion. !7. The method of claim 16 wherein the plant based polyol is one of soybean oil, castor oil, palm oil, canola oil or rapeseed oil. 18. The method of claim 1 1 wherein the natural oil-based polymer is an open cell, polyurethane foam material comprising the reaction product of a base polyol including a plant oil-based polyol of between 5 and 30 parts per hundred polyol, an isocyanate, water, a surfactant, and a crosslinker, wherein the polyol has a functionality of 2.3 to 2.9. |
BACKGROUND
[0001] The present disclosure relates generally to a headrest for a vehicle, and more particularly to an insert for a headrest formed using a bio-based material.
DESCRIPTION OF THE RELATED ART
[0002] Vehicles include a seat having a frame and a cover and cushion covering the frame. The cushion provides structure to the seat and offers comfort to an occupant of a seat. The cushion is usually a foam material formulated from petroleum initiated, oil-based polyurethane materials that are reacted with other products to make a foam cushion product. Petroleum-based foam polymers, such as expandable polypropylene
(EPP), are not biodegradable. This characteristic furthers an undesirable reliance on fossil fuels.
[0003] Foam formulation may come from renewable sources such as soybean, castor, and canola oils. However, there remains a lack of a commercially viable foam product, including for use in seating applications, utilizing any meaningful amount of sustainable, plant oil-based source materials, instead of petroleum oil-based materials. Such a foam product will have to meet current petroleum-based performance specifications, including mechanical properties such as hardness and rigidity, tensile, tear, elongation, compression set, stress, strain [hysteresis loss]) and comfort requirements for such seating applications. [0004] Accordingly, there is a need in the art to provide a sustainable, natural plant oil-based polyol foam that can meet the same specification requirements as a petroleum-based foam polymer and replace the use of such material.
SUMMARY
[0005] The present disclosure relates to a head restraint for a vehicle seat and method of forming the same is provided. The head restraint includes a connecting member. An insert formed using a natural oil-based polymer is secured to the
connecting member. An inner cushion layer covers the insert and a portion of the connecting member. The method includes the steps of forming a connecting member, forming the insert using the natural oil-based polymer foam material and securing the insert to the connecting member. An inner cushion layer is molded over the insert and a portion of the connecting member.
[0006] An advantage of the present disclosure is that a headrest is provided with increased bio-content material. Another advantage is that an insert portion of the headrest is formed using a natural or bio-based polymer, resulting in reduced reliance on petroleum-based products. A further advantage of the present disclosure is that a headrest insert is provided that is less dense and less costly. Still a further advantage is that the insert made using a natural oil having similar or better properties compared to current headrest inserts. Still a further advantage is that the bio-based polymer foam can replace the use of a petroleum based foam product and increases the recyclable content of the vehicle.
[0007] Other features and advantages of the present disclosure will be readily appreciated, as the same becomes better understood after reading the subsequent description taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a perspective view of a vehicle.
[0009] FIG. 2 is an elevational view of a vehicle seat.
[0010] FIG. 3 is an elevational view of an inner layer of an headrest.
[0011] FIG. 4 is a rear elevational view of a insert.
[0012] FIG. 5 is a front elevational view of a insert.
[0013] FIG. 6 is a side elevational view of a insert.
[0014] FIG. 7 is a flowchart of a method of forming a head restraint.
DESCRIPTION
[0015] Referring generally to the figures and in particular to FIG. 1 , a vehicle 10 is shown according an exemplary embodiment. The vehicle 10 of this example is an automotive vehicle, although any type of vehicle that includes a seat 12 may be contemplated, such as an airplane, boat or the like.
[0016] Referring to FIGS. 2-6, the vehicle seat 12 includes a seat base 16 and a seat back 14 connected thereto. The vehicle seat 12 also includes a head restraint 18 located and connected thereto an upper end of the seat back 14. Generally, the head restraint 18 extends upwardly from the seat back 14 and is configured to support the head of a seated occupant (not shown) as well as to restrain the head of an occupant due to the application of a sudden force. The seat back 14 can be pivotally coupled to the seat base 16 and the seat assembly 12 can also include a recliner mechanism 22 for selectively adjusting the seat back 14 relative to the seat base 16. The seat base portion 16 may be configured to allow the seat 12 to be selectively adjusted and positioned relative to the vehicle interior, such as via a track assembly 24. Each of the seat base, seat back includes an outer layer or seat trim cover 26 that may be fabricated from a decorative material such as upholstery, leather, fabric, etc. Each of the seat base and seat back includes an inner layer that assists in defining the contours of the seat assembly as well as providing support. An example of an inner layer is a foam material 20.
[0017] The head restraint 18 includes a headrest portion 28 and a connecting member 32 that connects the headrest 28 to the seat back 14. The position of the headrest 28 with respect to the connecting member 32 may be variable. In an example, the inclination of the headrest 28 may be fixed, while in another example the inclination may be adjusted.
[0018] Further, the headrest 28 for a vehicle seat 12 may include a displaceable subsection which faces the head of the seat occupant, and may be displaced, because of an accident, from a use position towards the head of the seat occupant into a safety position under the action of a drive device. For example, the headrest may include a first subsection facing the head of the seat occupant, a second subsection located substantially between the first subsection and a third subsection. The second subsection may be displaced from a use position towards the head of the seat occupant in a direction of displacement into a safety position. The first subsection may be a padded element against which the head of the seat occupant may rest and/or be supported. The third subsection of the head restraint is a base body for the head restraint. Inside the head restraint, a drive device causes the displacement of the first subsection in a direction of movement towards the head of the seat occupant.
[0019] The headrest 28 includes an outer layer or trim cover 26 that may be fabricated from a decorative material such as upholstery, leather, fabric, etc. The headrest 28 also includes an inner layer 30 that assists in defining the contours of the seat assembly as well as providing support. An example of an inner layer 30 is a flexible or semi-flexible polyol shell, such as polyurethane ("PU") material as shown in FIG. 3. This shell provides a cushion feel for a passenger or driver.
[0020] The headrest connecting member 32 may be accomplished using various techniques, such as by a tubular member in this example. However, alternatively other fastening options (not shown) may be provided between the seat back 14 and the headrest 28. The connecting member 32 may provide for a rigid connection of the headrest 28 to the seat back 14, or height-adjustable connection, and/or an inclination- adjustable manner, or the like.
[0021] The headrest 28 also includes an insert 34 disposed between the connecting member 32 and headrest inner layer 30. The headrest insert 34 is a generally planar member having a shape conforming to the overall shape of the headrest 28. The headrest insert 34 may include other features, such as an attachment feature for securing the connecting member 32 to the headrest insert 34.
[0022] The headrest insert 34 is molded from a rigid or semi-rigid natural oil polyol-based polymer (NOP). An example of a process for forming natural oil polyol- based polymer foam material for use in a vehicle seat 12 is disclosed in commonly assigned patent application PCT/US2009/062767 (which claims priority to U.S. provisional application Nos. 61 /109,773, filed October 30, 2008, and 61 /1 10,258, filed October 31 , 2008, both to McEvoy et al.), which is incorporated by reference herein. The process produces an open cell, polyurethane foam having non-petroleum based or initiated polyol materials. In an example, NOP's include natural plant oils such as soybean oil, castor oil, palm oil, canola oil and rapeseed oil or the like that are sustainable and recyclable. The open cell, polyurethane foam material may be provided from the reaction products of a polyol material including a natural oil-based polyol (with approximately 10% to approximately 90%, and or from approximately 22% to approximately 70%, bio-content) present in the polyol in an amount of between 1 and 30 parts per hundred polyol, an isocyanate, a blowing agent, a cell opener, water, and a cross linker(s), to provide a foam material. In another example, the open cell, polyurethane foam material comprises the reaction product of a base polyol including a plant oil-based polyol of between 5 and 30 parts per hundred polyol; an isocyanate; water; a surfactant; and a crosslinker, wherein the polyol has a functionality of 2.3 to 2.9. In an example, a polyurethane-based foam material, of both the soft and firm variety can be formed according to a "one shot" process in which, essentially, a first (typically a polyol) stream and a second (typically an isocyanate) stream are mixed and allowed to cure in a mold to form a foam product. The polyurethane-based foam product may be composed of polyurethane-based base polyol resin, a polyurethane- based copolymer polyol (co-polyol) resin, water, a cross-linker(s), a catalyst (or catalyst package), a surfactant, a cell opener / regulator, and an isocyanate such as, for instance, TDI, MDI or blends thereof (generally, such blends are not less than 5% of either TDI or MDI ; e.g., TM20, a blend of 80% TDI and 20% MDI) reacted according to a system 10 as shown in FIG. 1 . Various additives can, as known, also be employed to provide different properties.
[0023] The NOP based foam material used for the insert 34 can be made to achieve hardness and density regulations set forth by the automobile industry. All front row headrests must pass a United States performance test, FMVSS 202A with respect to performance of an insert inside the headrest. For example, an insert material having a density of at least 2.8 kg/ m3 can be used for a foam insert to achieve the hardness and compression strengths designated for safety. These properties can be characterized as rigidity of the polymer material. In an example, a bio-based foam insert 34 advantageously replaces a petroleum based foam material insert, like an EPP or styrene foam insert. The bio-based foam insert can achieve the hardness and compression strength properties set forth by industry regulations. In a further example, the bio-based foam insert achieves sufficient rigidity properties (i.e., hardness and strength), while being less dense than a EPP foam insert. In yet a further example, the bio-based foam insert is less costly than an EPP or other plastic insert. In an example, the bio-based foam insert can be a NOP-based polyurethane foam. The foam is a mixture NOP with rigid or semi-rigid polyurethane (PU). The mixture foam can further be used as a replacement for various polyol-based materials throughout the vehicle including but not limited to, seat cushions, instrument panel, head liner, doors, etc.
[0024] For example, a longer carbon chained polymer may yield a flexible or semi-flexible material, which may be used for a cushion or the softer, inner shell on the headrest 28 or the like. A shorter carbon chain polymer, like EPP can have a lower molecular weight and be rigid or semi-rigid. Polyurethane can also be fabricated to be shorter, i.e., rigid or semi-rigid, or longer, i.e., flexible or semi-flexible, carbon chain polymer. The NOP polyol can likewise be formed as a short carbon chain polymers and therefore can provide similar properties with expandable polypropylene (EPP). Particularly, in an example, when NOP is mixed with rigid or semi-rigid PU, a foam insert can be made that expresses sufficient rigidity (i.e., hardness) and strength properties. The content of the insert 34 can vary in amount of bio-based material depending on desired properties and densities.
[0025] NOP are generally polar molecules and thus form sufficient adhesion with PU. An NOP-based PU foam insert can provide sufficient rigidity and strength properties needed for a headrest insert 34 while providing a less dense material and at a lower cost. Moreover, the bio-content increases while lowering reliance on petroleum products. The NOP-based PU foam insert 34 can similarly be at least partially biodegradable as a result of its bio-content. [0026] Advantageously, the insert 34 made from an NOP-based polyol can be fabricated to be lighter weight than traditional foam or plastic inserts made from petroleum based products. In a further example, the NOP-based polyol insert 34 can express better adhesion properties as compared to traditional inserts. In an example, the composition of the NOP-based insert 34 can be modified or adjusted to achieve desired properties.
[0027] An insert 34 made using an NOP-based polyol can withstand a broad transition glass temperature ("T g ") range, such as -30C to + 100C. If the insert material is exposed to too high of temperatures, it may become softer. Similarly, if exposed to too cold of temperatures, it may become brittle. By modifying or adjusting the composition of the insert, the T g range can be broadened and thus the insert is functional across a greater temperature range. The T g range of a particular insert 34 can be adjusted according to desired properties. Moreover, energy management associated with the safety regulations, may also be improved as a result of a broader T g range. For example, if the T g range is broader, the material can be fabricated to provide suitable and desired energy distribution throughout the insert, such as due to the application of a force. Thus, when the head restraint experiences a sudden impact from a passenger's head, the insert 34 will maintain desired energy distribution properties over a broader temperature range.
[0028] Referring to FIG. 5, a method of forming a head restraint 18 is provided. The method begins in block 100 and includes the step forming an insert 34 from a NOP polyol material. For example, the insert 34 may be molded to achieve a predetermined shape using an available molding technique. The methodology advances to block 1 10 and a connecting member 32, such as a tubular member, is formed,. The methodology advances to block 120 and the insert 34 is secured to the connecting member 32 using a suitable connecting technique, such as a fastener, an interference or snap fit connection, welding, and adhesive, or the like. The methodology advances to block 130 and the connecting member with an NOP-based polyol insert 32 secured thereto is placed in a mold to form the headrest inner layer. The methodology advances to block 140 and a foam material is poured into the headrest inner layer mold using a technique such as pour in place, or injection molding or the like. The foam cures to form a unitary head restraint 18 having an inner layer 30, insert 34 and connecting member 32. The methodology advances to block 150 and the head restraint 18 is demolded from the mold and finished. For example, a decorative outer cover 26 may be placed over the head restraint.
[0029] Many modifications and variations of the present disclosure are possible in light of the above teachings. Therefore, within the scope of the appended claim, the present disclosure may be practiced other than as specifically described.