The present invention relates to body support assemblies, and more particularly, to a load bearing assembly creating a body support assembly over an opening defined by a support structure, such as the seat or back of a chair or bench, or a support surface of a bed, cot or other similar structure.
There are continuing efforts to develop new and improved load bearing assemblies. One of the objectives of these assemblies is to create a durable and inexpensive body support assembly that is relatively easy to manufacture and that can be easily attached to a support structure. For example, the load bearing assemblies can be configured with a suspension member, such as a membrane, or series of straps, which support the body of the user.
Load bearing support surfaces that currently exist generally have a linear force/deflection profile, which gives the body support assembly the feel of a drum or trampoline. In seating or other support-based applications, this may result in an uncomfortable and sometimes ergonomically unacceptable body support assembly. In some applications, the body support assembly is encapsulated by a foam or embedded in another structure to compensate for these deficiencies. However, the ability to tune the physical characteristics of a conventional molded seat is relatively limited and difficult to predict. Different materials and different material thicknesses can be used to add a limited degree of control over the characteristics of the seat, but this nominal level of control may not be adequate in many applications.
Conventional attachment mechanisms such as screws, adhesives, or the like may be utilized to attach the suspension members to the support structure. However, such mechanisms may be problematic because of the extra costs and time associated with additional materials and manufacturing steps. Accordingly, there continues to be a desire for providing a secure attachment mechanism for attaching the suspension member, or other support surfaces, to the support structure.
In one embodiment a body support assembly includes a pair of spaced a pair of spaced apart frame members defining an opening therebetween, where at least one of the frame members comprises a plurality of loops spaced along the frame, where each of the loops defines an aperture and an elastomeric member extending across the opening between the pair of spaced apart members, where the elastomer member comprises a retention portion disposed through the aperture.
In another embodiment the load bearing structure includes a pair of spaced apart frame members defining an opening therebetween where the pair of frame members comprises a plurality of continuous loops spaced along each frame member, where each of the loops defines an aperture and an elastomeric member extending across the opening between the pair of spaced apart frame members, where the elastomeric member comprises a first end having a first retention portion forming part thereof, the first retention portion being disposed through one of the plurality of loops on one of the pair of spaced apart frame members, and a second end having a second retention portion forming part thereof, the second retention portion being disposed through one of the plurality of loops on the other of the pair of spaced apart frame members.
A method of manufacturing a body support assembly includes providing a pair of spaced apart frame members, which defines an opening, at least one loop, and an elastomeric member, attaching the elastomeric member to one of the spaced apart frame members by inserting a retention portion of the elastomeric member through the at least one loop, stretching the elastomeric member across the opening, and attaching the elastomeric member to the other of the spaced apart frame members.
In another embodiment, a method of use of a body support assembly includes providing an elastomeric member stretched across a pair of spaced apart frame members, where the elastomeric members have a retention portion coupled to one of a plurality of loops spaced along the frame, applying a load to the elastomeric member, stretching the elastomeric member, and rotating the retention portion with respect to the frame members without decoupling the retention portion from the loop.
In yet another embodiment, a body support assembly comprises a pair of spaced apart frame members defining an opening therebetween, an elastomeric member extending across the opening between the pair of spaced apart members, where the elastomeric member is connected to the frame members, a cushion material configured to at least partially encapsulate the elastomeric member, and a relief channel formed within the cushion material.
In yet another embodiment, a method of manufacturing a body support comprises providing a pair of spaced apart frame members which define an opening and an elastomeric member, encapsulating the elastomeric member with a cushion material, forming at least one relief channel within the cushion material, and securing the elastomeric member across the opening between the pair of spaced apart frame members.
The foregoing paragraphs have been provided by way of introduction, and are not intended to limit the scope of the following claims. The various preferred embodiments, together with further advantages, will be best understood by reference to the following detailed description taken in conjunction with the accompanying drawings.
The invention is described with reference to the drawings in which like elements are referred to by like numerals. The relationship and functioning of the various elements of this invention are better understood by the following detailed description. However, the embodiments of this invention as described below are by way of example only, and the invention is not limited to the embodiments illustrated in the drawings.
A body support assembly 10 according to one embodiment of the present invention is illustrated in
For example, as shown in
Similarly, as shown in
Referring back to
In one embodiment, the support structure 12 has a first frame member 18 which is substantially parallel to a second frame member 20, and a third frame member 22 substantially parallel to a fourth frame member 24. The first and second frame members 18, 20 are generally perpendicular to the third and fourth frame members 22, 24. However, the number and orientation of the frame members 14 with respect to one another is application dependent. The frame members 14 may be attached to one another through conventional attachment devices, including without limitation, welding, adhesives, mechanical fasteners, or the like, and combinations thereof.
As further shown in
Referring back to
As shown in
In one embodiment, as shown in
It is important to note that the respective heights, as measured from the longitudinal axis A, need not be equivalent, or consistent, along the length of the first and second frame members 18, 20, so long as the shape of the wire 28 generally defines at least one opening, or aperture 30, between the frame member 14 and the wire 28. In this embodiment, the shape of the wire 28 forms a series of openings 30 along the length of the first and second members 18, 20, as shown in
A strap 38 is disposed across the opening 16, and between the first and second frame members 18, 20. The strap 38, as better shown in
The apertures 46 formed within the strap 38 also facilitate the process of encapsulating the straps 38 with a cushion material 72. For example, and without limitation, foam openings, or apertures 46, also can be sized and positioned to optimize the stretch and flexibility properties of the straps 38, individually and collectively. The size, location and overall configuration of the apertures 46 can be optimized to allow the cushion material 72 to be disposed through the apertures 46 to encase, and secure, the strap 38, or membrane 11, on both faces of the strap 38, or membrane 11. In one embodiment, straps 38 may have an aperture 46 with a minimum gap for foam encapsulation of 0.250 inches wide by 1.50 to 2.75 inches long. The cushion material 72 functions to lock the crystalline structure, fibers, or filament of the membrane 11, or strap 38, together to provide for the desired distribution of seating loads throughout the membrane 11 and to avoid areas of stress concentration. The cushion material 72 also functions to shrink the membrane 11 to further induce tension in the membrane 11 and insure its ability to comfortably resist seating loads. The cushion material 72 can be of any suitable foam material such as a urethane foam.
The cushion material 72 may encapsulate, and form part of, the seat 15 as shown in
Similarly, the cushion material 72 may also encapsulate, and form part of, the back 17 as shown in
In an alternative embodiment, as shown in
The relief channels 74 may be positioned anywhere along the cushion material and may be placed in locations requiring greater deflection to provide enhanced comfort. For example, in one embodiment, as shown in
The relief channels 74 may be disposed in any direction with respect to the longitudinal axis A, and may be connected to one another to form a relief zone. For example, as further shown in
The dimensions of the relief channels 74 may vary; however in one embodiment, the relief channels 74 have a width of approximately 7 mm, with the upper relief channels 76 each having a length of approximately 155 mm and are located approximately 90 mm away from the longitudinal axis A in the X direction. The center relief channel 78, located along the longitudinal axis A, may have a width of approximately 7 mm and a length of approximately 310 mm. The area of the rectangle 80 formed by the relief channels 72 may have an approximate width of 105 mm and an approximate height of 151 mm along the longitudinal axis A. The depth of the relief channels 74 is such that there is approximately 12 mm of foam between the bottom of the channel 74 and the membrane 11. Additionally, the depth of the relief channels 74 may further vary such that there is anywhere between 5 to 20 mm of foam between the bottom of the channel 74 and the membrane 11. In another embodiment, the depth of the relief channel 74 may range from 10 to 15 mm of foam between the bottom of the channel 74 and the membrane 11. Alternatively, the depth of the relief channels 74 may also be equal of the thickness of the cushion material 72, and therefore may form an aperture completely through the cushion material 72, or may be equal to half of the thickness of the cushion material 72 and therefore may form an aperture up to the membrane 11.
The apertures 46 permit a specific amount of extension of the strap 38, or membrane 11, in the desired direction without significant stretching of the strap 38, or membrane 11. The apertures 46 may be elongated as shown in
In the embodiment shown in
The straps 38, in the embodiment shown in
In the illustrated embodiment, the straps 38 of the membrane 11 are molded from a thermoplastic polyether ester elastomer block copolymer. Suitable materials of this type include that available from DuPont under the Hytrel® trademark, and that are available from DSM under the Arnitel® trademark. A variety of alternative elastomers may be suitable for use in the present invention. The thickness of the molded membrane 11 will vary from application to application, depending primarily on the anticipated load and the desired stiffness of the surface. In standard seating applications, the support portion of the membrane 11 may have an average thickness prior to any desired orientating of approximately 20-40 mils. In one embodiment, the strap(s) 38 forming the molded membrane 11 is orientated in one direction (i.e. the X direction) to provide creep resistance and elasticity in the direction of orientation. For ease of reference, it is contemplated that the term “membrane” 11 may mean an individual strap 38 or plurality of straps 38 which can be orientated in different arrangements. The membrane 11 is orientated by increasing the alignment of the crystalline structure of the elastomeric membrane 11 on a molecular level so that its support and other load baring characteristics are altered. Typically, the membrane 11 is orientated to such a degree that the orientated membrane 11 has a materially different load bearing characteristics in the orientated direction than in other directions.
One method for orientating the membrane 11 is through stretching. The amount of stretch required to obtain the desired alignment will vary from application to application, but in most applications the desired degree of alignment will occur when the membrane 11 is stretched to roughly two times its original dimension. Although the elastomeric membrane 11 may be orientated by stretching the membrane 11, it may be possible in some applications to orient the membrane 11 using other processes. For example, it may be possible to orient certain material by hammering or other forms of compressions rather than stretching the membrane 11. It should be noted that many elastomeric materials, including molded Hytrel®, have essentially no elasticity and are susceptible to a high degree of creep when in a molded form. The orientation process of the present invention causes a significant change in the properties of the elastomeric material. For example, orientation of the membrane 11 increases the elasticity of the material and decreases its inherent susceptibility to creep.
As noted above, the elastomeric membrane 11, or each strap 38, is molded using conventional techniques and apparatus. For example, the elastomeric membrane 11 may be injection molded using a conventional injection molding apparatus having a die that is configured to provide a membrane with the desired shape and features. In this embodiment, the elastomeric membrane 11 is manufactured by injecting the desired material into the die cavity. The die is designed to provide a molded blank that will take on the desired shape once any desired orientation has taken place. For example, the dies are configured to form a part that will have the desired shape and dimensions after the orientation step is complete. After molded, the membrane 11, or each individual strap 38, may be stretched or otherwise orientated in one direction. If orientation is achieved through stretching, the precise amount of stretch to be applied to a given membrane 11, or strap 38, will depend on the configuration of the membrane 11 and the desired support characteristics. In many applications, it will be necessary to stretch the membrane to at least twice its original length to achieve the desired alignment. The membrane 11 may be stretched using conventional techniques and apparatuses. As a result of the increase in alignment of the crystalline structure, the membrane 11, or each strap 38, will not fully return to its original length after being released from the stretching equipment. Rather, the orientated membrane 11 will be elongated a certain portion of the stretched distance, with the precise amount of elongation being dependent in part on the material characteristics of the membrane material. Once any desired orientation has taken place, the membrane 11 can be mounted directly to the support structure as described herein. Various aligned materials and structures are disclosed in U.S. Publication No. 2005/0279591, published Dec. 22, 2005, U.S. Publication No. 2006/0267258, published Nov. 30, 2006, and U.S. Publication No. 2006/0286359, published Dec. 21, 2006, the entire disclosures of which are hereby incorporated by reference.
As an alternative to stretching, the membrane 11 may be orientated by compression. In one embodiment, the membrane 11, or each strap 38, is placed in a die or other structure that constrains the membrane 1I1 on all sides other than at least one side that corresponds with the desired direction of orientation. Opposed sides may be unconstrained to permit the material of the membrane 11 to flow from both sides along the direction of orientation. Alternatively, only a single side may be constrained, thereby limiting material flow to a single side. A compressive force is then applied to the membrane 11. For example, a press can be used to compress the membrane 11 within the die. Sufficient compressive force is applied so that the material begins to flow in the unconstrained direction. This, in effect, causes the membrane 11 to extend and its crystalline structure to become increasing aligned in the direction of orientation. The amount of force applied to the membrane 11 may vary from application depending on the desired degree of alignment or orientation. Each individual strap 38 forming the membrane 11, if more than one strap 38 exists, may be individually orientated. Moreover, in some applications, it may be desirable to orient only select peripheral portions of the membrane 11 or strap 38. When desirable, this may be achieved by applying localized stretching or localized compression of the membrane 11 or each strap 38.
In one embodiment, the straps 38 each have a generally rectangular cross-section as shown in
As shown in
As shown in the embodiment in
As explained above, the wire 28 may be located on the top, bottom, interior, or exterior sides 32, 34, 36, 37 of the member 14. Accordingly, the ends 40, 42 of the strap 38 must have a conforming geometry. For example, the first end 40 is configured to couple with the wire 18 coupled to the bottom side 36 of the frame member 14, and the second end 42 of the strap 38 is configured to couple with a wire 28 which is located on the top 32 of the member 14. Of course, the location of the recessed portion 44 of the strap 38 is also application dependent.
Although the present invention has been described with reference to preferred embodiments, those skilled in the art will recognize that changes may be made and formed in detail without departing from the spirit and scope of the invention. It is therefore intended that the foregoing detailed description be regarded as illustrative rather than limiting, and that it be understood that it is the following claims, including all equivalents, that are intended to define the scope of this invention.
This application claims the benefit of U.S. Provisional Application No. 61/101,423, filed Sep. 30, 2008 and U.S. Provisional Application No. 61/058,783, filed Jun. 4, 2008, the entire disclosures of which are hereby incorporated herein by reference.
Number | Date | Country | |
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61101423 | Sep 2008 | US | |
61058783 | Jun 2008 | US |