Field of the Invention
This invention pertains generally to seat bottoms and seat bottom construction, but may have more general applicability to overall seat construction design and techniques. More specifically, the invention pertains to a molded seat bottom which incorporates and has been molded around an insert or inserts shaped in particular ways, having particular characteristics, comprised of particular materials chosen to impart desirable characteristics to the seat, including heating elements, and/or methods and systems for producing seats of this type.
Description of the Related Art
Polyurethane, produced by combining monomers including isocyanate functional groups and hydroxyl groups, is a known material for forming resilient seating of all types, including motorcycle seats. The combination process typically requires a catalyst and, for applications similar to those of interest in the instant invention, a mold of some type. In this process, liquid isocyanate and resin are blended at a specific ratio, and the reacting liquid is dispensed into the mold and allowed to cure, then the finished part is demolded. Typically, in high volume manufacturing applications, a dispensing unit is used to combine and dispense the reacting liquid into the mold used in forming the finished piece in a process commonly known as reaction injection molding (“RIM”).
Examples of prior art patents that may be found to have teachings relevant to the invention are:
However, there is a continuing need for devices providing new and improved features in the field of the invention. Further, there are no prior art devices possessing the unique features and advantages inherent in my invention.
The instant invention teaches a seat having insert(s) or “mat(s)” incorporated therein intermediate its upper and lower surfaces so as, in most cases, to be generally parallel to the upper surface of the seat (i.e., the surface on which the posterior of the user will rest). The primary embodiments of an insert/mat described herein are comprised of material that conforms to the contours of the user's body over a period of time, has certain “rebound” properties (or spring-like performance), and features areas adapted to underlie the perineum and/or ischiums of a user seated on the seat, which areas are softer than the rest of the insert either by virtue of included gap(s) in the insert or by virtue of a softer material filling said gap(s). In another embodiment of the invention, the insert(s) is/are adapted and shaped to underly, e.g., the perineum or ischiums of a user and is/are comprised of a softer material than the surrounding foam. Other insert embodiments may include heating elements. Materials for use in forming such inserts may include a variety of materials including gel-like materials, gel packets, air packets (which may be made adjustable in terms of pressure), and foams.
In the preferred embodiments taught herein the aforesaid inserts are completely encapsulated and enclosed by the foam materials making up the seat with this being advantageously accomplished by molding the seat around the inserts. This is made possible, in accordance with the teachings of the invention, by providing means for suspending inserts within the mold used in forming the seat so as to be in proper spaced relationship to the upper surface of the seat (on which the user will be seated) and the lower surface of the seat (facing away from the seated user) when formed in the mold. Thus, my invention is enabled to provide a more comfortable seat for the user with—even in the most basic embodiments discussed—enhanced abilities to conform to the user's body and enhanced springiness, while limiting pressure on the perineum. In addition, the “integrated or molded in” aspect of the invention maintains the integrity of the exterior foam seat surfaces, in particular the upper surface of the seat/foam. In this manner, the essential “mechanics” or “workings” of my invention (as provided by said insert(s)) are “hidden” inside the foam making up the seat; protected thereby from wear, weather and the elements; and creating little or no interruption of the top surface in terms of aesthetics or the look/feel of upholstery fit, etc. Further, carefully selecting and designing the properties of the various foams, gels and/or other materials involved, i.e., insert materials, perineal gap materials, ischial gap materials, heating insert materials, and surrounding foam, provides the ability to control the overall suspension effect with zone density control, to better adapt the final composite to the human anatomy and pressures for various applications, and to provide a heated seat with elements hidden from view and protected from wear and weather.
Thus, as opposed to simply adding the same (or a similar) pad on top of the molded foam (which might be an obvious approach), “embedding” or “in-molding” creates a subtle transition between the generally firm areas of the foam and the softer pressure relief areas. It creates soft spots and/or springy areas deep within the foam. Also, simply adding a foam pad on top (consisting of soft, springy and/or firm sections), would result in too abrupt a transition between areas of varying characteristics and density, as opposed to the more “blended” transitions achieved by the instant invention. Another potential problem that adding a pad on top would create (consisting of presumably bonded foam composite of varying densities), is the potential for delamination of the pad composite due to wear and sheer forces. By molding foam around the pad, all of the above issues are solved, and we have created a foam cushion composite with incredibly strong construction and gentle transitions between areas of firm support and soft areas.
These goals and others are all accomplished in an efficient and economical manner using the method I have developed for molding the seat around an insert or inserts including and providing the characteristics described.
The process, construction and apparatus used in the instant invention can best be understood by careful and ordered review of the above-referenced drawing figures, beginning with
With the background previously provided, especially in regard to
In the embodiments having larger inserts 10, it is sometimes advantageous to include openings 11 so that reacting liquid 30 can freely move through and around the seat inserts 10 so that there are no unfilled gaps left in the molded seat 20. These holes/openings 11 may be of varying size, frequency of distribution or not included at all, depending on the flow characteristics and/or requirements of each particular mold/insert/seat. Thus, they are not shown in all illustrations, particularly those where open perineal openings 13 and/or ischium openings 19 provide alternate means of distribution which have been found sufficient by themselves for the aforesaid purpose without the inclusion of openings 11. However, the primary purpose of perineal openings 13 and/or ischium openings 19 is to create, include and incorporate a softer area or cushion below the perineum and/or ischiums of the person seated on seat 20.
Perineum/perineal openings 13 are provided as the perineum is more sensitive than surrounding areas for many people. By leaving the perineal opening 13 unfilled (as illustrated in
As will be appreciated from the drawing figures (and in accordance with their anatomical purpose of underlying the perineal regions of a user), perineal opening 13 and perineal inserts 14 are preferably elongate, which shape defines a long axis that will be aligned with the bilateral axis of the user when seated on seat 20, and serve to separate seat 20 and/or mat/insert 10 into two halves, each of which would support, anatomically, respective buttocks/thighs of the user.
Insert 10 is preferably formed from closed cell foam with characteristics important to the purposes of my invention, though other materials having similar characteristics or other chosen characteristics can be used for this purpose. One such characteristic is “Compression Set”, a property that describes the fact that a permanent foam setting or deformation is achieved when a load is place on the seat insert 10 over a period of time. In the instant application this is advantageous because it allows the insert to form itself to the contours of the user's body over a period of time, adapting itself to the particular shape and configuration of the user for added user comfort. Vinyl nitrile foam has been found ideal for these purposes. Another important property of any such insert 10 is “rebound” (or spring-like performance), which is a property of vinyl nitrite foam by virtue of its closed cell construction. The inclusion and incorporation of insert 10 in molded seat 20 results in a final molded foam composite (seat 20) that is enhanced with these added properties derived from insert 10. However, as previously mentioned. other materials may be useful for this purpose, particularly other closed cell foam materials.
Review of
As will be noted, pegs 3 can be advantageously formed with a base portion 3A (adapted for insertion in a registering opening provided in mold base portion 3A), support portion 3B (which holds the insert 10 in place within the mold 1 in spaced relationship to the upper mold portion 1A and lower mold portion 1B when the mold 1 is closed), a ledge portion 3C (with a substantially conical shape providing direct support of the insert 10 from below while allowing the seat 20 to be withdrawn—due to its sloped portion—from the mold 1 when it is formed), a barrel section 3D (dimensioned in terms of diameter and length to fit the width of mounting peg openings 12 and the thickness of insert 10), and a substantially conical head 3E (adapted to push through the somewhat flexible material of insert 10 while holding the insert 10 in place from above). Thus, insert 10 can be pressed onto the pegs 2 in mold 1 (as illustrated in
However, as a practical matter, it has also been found that the addition of a flexible elastic band 31 (typically in the form of a fairly large circular “rubber” band) can assist and facilitate the molding process and that the pegs 3 of the invention are ideally shaped and structured for this purpose. The need for such facilitation arises from the fact that the reacting liquid 30 can churn and grow inside the mold in such a manner that it generates enough force to occasionally dislodge element(s) placed on pegs 3 (e.g., heatable insert 16 and/or seat insert 10) and cause it/them to float off of pegs 3 despite the pegs enlarged head 3E. This can be remedied by stretching an elastic band 31 around pegs 3 intermediate inserts 10, 16 and peg heads 3E as illustrated in
A problem to be dealt with in this context is that the heatable insert 16 may become too rigid when traditional heating pad technology is used. Such heating pads utilize cloth carrier sheets to form the body of the heating pad sandwiching the resistive wire (which in this case would be analogous to, respectively, heatable insert 16 and wires 17). However, the reacting/pressurized liquid 30 forms foam that saturates/plugs such cloth heating pad carrier sheets, creating a very rigid end product that sticks to the material of seat 20, which is counterproductive to comfortable seating. Consequently, in the invention it has been found beneficial to form the heatable insert 16 from a substance that cannot be saturated in this manner. Thus, a preferred embodiment of the invention uses heatable inserts 16 formed using a material that repels reacting liquid 30 such as conformable PTFE, vinyl, or silicone carrier sheets with the right strength, conformability (flex), and temperature rating. By not bonding/sticking to the reacting foam while it is forming, the heatable insert 16 creates its own individual “cell” and is allowed to “float” independently inside this cell in the foam comprising seat 20, thus allowing movement (flexibility) within the final foam part. Another way to avoid the problems set forth above is to replace the carrier sheets discussed above in reference to heatable insert 16 with a “conformable adhesive film” and weaving/placing wires 17 onto the adhesive surface 32 of said film, which is oriented so as to face the foam insert 10 and then sticking the heatable insert 16 formed in this manner to the foam insert 10 before molding it in (s illustrated in
The ischium openings 19 illustrated for both seat insert 10 and heatable insert 16 in
Alternatively, particularly with regard to the heatable insert 16, the size of the seat ischium openings 19 can be left open, but minimized as illustrated in
1 Mold
2 Dispenser
3 Pegs
10 Seat Insert
11 Insert openings
12 Mounting peg openings
13 Perineal opening
14 Perineal insert
15 Ischium insert
16 Heatable insert
17 Embedded heating elements/wires
18 Lead wires for heating element
19 Ischium opening
20 Seat
21 Openings left in seat 20 by part 3B
30 Reacting liquid
31 Elastic Band
32 Adhesive Surface
In view of the foregoing, it should be clear that numerous chances and variations can be made without exceeding the scope of the inventive concept outlined. Thus, though the preferred embodiment is illustrated in the context of a motorcycle seat, the teachings of the invention are not necessarily restricted to such seats. Indeed, potential applications range from seats for all kinds of riders (horseback/motorcycle/ATV) to more mundane chairs and seats used in other applications. Further, though the preferred materials comprising the seat are specified, other materials with similar support and/or molding characteristics may certainly be substituted. In addition, though single layer mats/inserts are shown, the inventive concept does not preclude multiple mat/insert layers or further subdivision of the mat/insert in terms of its constituent materials than those shown. Accordingly, it is to be understood that the embodiment(s) of the invention herein described is/are merely illustrative of the application of the principles of the invention. Reference herein to details of the illustrated embodiment(s) is not intended to limit the scope of the claims, which will themselves recite those features regarded as essential to the invention
This application is a continuation-in-part of parent application Ser. No. 13/775,111 titled “Molded Seat” filed Feb. 22, 2013, which was a continuation-in-part of parent application Ser. No. 13/624,905 titled “Molded Seat” filed Sep. 22, 2012 the same being incorporated herein by reference and claiming priority thereto.