Foam is commonly used as a cushioning material in a variety of applications. For example, mattresses are commonly formed of memory foam due to its ability to mold to the body to provide even support. However, memory foam also has various undesirable properties. Many individuals complain that memory foam feels dead, meaning that it tends to absorb force as opposed to springing back as would a traditional spring mattress or a conventional polyurethane non-memory foam. It can also be difficult to roll over on a memory foam mattress due to the indentation that is formed around the body. Additionally, memory foam has minimal breathability and is therefore too hot for many individuals.
To address such disadvantages of foam, and particularly memory foam, other materials have been used for mattresses and other cushioning articles. For example, mattresses, such as those marketed under the Purple trademark, have been formed of a gelatinous material having an adjoining hollow column shape. Mattresses made of this gelatinous material provide local instability and general stability due to the columns' ability to buckle where needed such as under an individual's hip. However, such mattresses are extremely heavy and require specialized manufacturing.
The present invention extends to foam cushions having an orthogonal alternating structure and to cushioning articles formed of or containing such foam cushions. The orthogonal alternating structure can be formed by bonding together layers of foam where the layers are formed from at least two types or stiffnesses of foam. The layered arrangement of foam can be cut, if necessary, to create a foam cushion where the layers extend along a length or width of the foam cushion, or orthogonal to the direction of the force that the foam cushion is intended to support. Foam cushion components having bases and layers that emanate from the bases could be used to form the foam cushion.
In some embodiments, the present invention may be implemented as a foam cushion that includes layers of foam that are arranged along a length of the foam cushion.
In some embodiments, the present invention may be implemented as a cushioning article that includes a first foam cushion. The first foam cushion may include layers of foam that are arranged along a length of the foam cushion.
In some embodiments, the present invention may be implemented as a method for manufacturing a mattress. Sheets of foam can be stacked along an axis to form a layered foam block. The layered foam block can be cut along the axis to form a foam cushion comprising layers of foam. The foam cushion can be oriented within the mattress to cause layers of foam to be arranged along a length of the mattress.
In some embodiments, the present invention may be implemented as a method for manufacturing a foam cushion. A first piece of foam and a second piece of foam can be created in a desired shape. The first piece of foam and the second piece of foam can be cut into corresponding layers. Alternating layers of the first piece of foam and the second piece of foam can be bonded together to form the desired shape.
In some embodiments, the present invention may be implemented as a method for assembling a foam cushion. A first foam cushion component that includes a base and layers that emanate from the base can be obtained. A second foam cushion component that includes a base and layers that emanate from the base can be obtained. The layers of the first foam cushion component can be inserted between the layers of the second foam cushion component to form the foam cushion.
This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter.
Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:
In this specification and the claims, the term “cushioning article” is intended to encompass mattresses, pillows, couches, car seats, aircraft seats, after-market seat cushions, and other furniture or articles that provide cushioning to an individual. A cushioning article may include one or more foam cushions configured in accordance with one or more embodiments of the present invention. A foam cushion configured in accordance with embodiments of the present invention may also be separate and/or independent from a cushioning article and may be covered with a fabric or plastic film or other pliable covering. The term “approximately” means within 10% of the stated value.
In accordance with embodiments of the present invention, a foam cushion can be formed of layers of foam that have an orthogonal alternating structure. In this context, the term “orthogonal” is intended to represent that the layers are arranged along an axis that is orthogonal to the force that the foam cushion is intended to support. The term “alternating” is intended to represent that the layers are formed from alternating types or stiffnesses of foam.
The thickness (LT) of each layer 101, 102 (i.e., the dimension of the layer along the length of foam cushion 100) can be less than the height of each layer to thereby create local instability. In other words, this smaller thickness can cause each layer 101, 102 to collapse more easily under a downward force such as from an individual's hip or shoulder when lying on foam cushion 100. However, the combination of layers 101 and 102 can still provide general stability across foam cushion 100. For example, if foam cushion 100 is a mattress, individual layers 101 and 102 can collapse under localized pressure from an individual's hip and shoulder while the combination of layers 101 and 102 extending across a broader portion of the body such as the torso can exhibit general stability to provide back support.
Because layers 101 can be formed of a different type of foam from layers 102, foam cushion 100 can exhibit synergistic benefits relative to the use of a single type of foam or a different structural arrangement of foams. Stated another way, the type of foam for layers 101 can have a first set of properties and the type of foam for layers 102 can have a second set of properties, and the orthogonal alternating structure of these layers can cause the first and second set of properties to yield synergistic benefits. For example, layers 101 could be formed of a relatively stiff foam and layers 102 could be formed of a relatively soft foam such that each layer will collapse/compress differently from the adjacent layer. As other examples, layers 101 and 102 could have different breathability, bounce-back, and/or softness.
The ratio between the height of each layer (LH) and the thickness of each layer (LT) can be selected to achieve a desired instability of the layers under significant pressure (e.g., due to the hips or shoulders when an individual lies on a mattress). In some embodiments, this ratio may be at least 2.5, at least 3.0, at least 3.5, at least 4.0, at least 4.5, or higher. A higher ratio may cause the layers to exhibit greater instability, or in other words, to collapse under pressure to better form to an individual's body.
The IFD of the foams used for each layer may also be selected to achieve a desired instability. For example, alternating layers of higher IFD foam with layers of lower IFD foam may make it easier for the layers of higher IFD foam to buckle because the layers of lower IFD foam do not provide significant resistance to such buckling (i.e., the layers of lower IFD foam may compress to accommodate the buckling of the layers of higher IFD foam).
The layered structure of a foam cushion configured in accordance with embodiments of the present invention allow this instability to occur only in response to sufficient loading/pressure. Accordingly, a mattress configured in accordance with embodiments of the present invention may be giving only under the hips or shoulders while remaining firm under the other parts of the body.
As one particular example, foam cushion 100 could represent a mattress or a portion of a mattress, and layers 101 could be formed of latex foam (or latex foam rubber) while layers 102 could be formed of memory foam. In such cases, the latex foam can give the mattress some properties desired in a mattress, such as breathability, bounce-back when shifting places on the mattress, and softness. Memory foam lacks these properties. It is known for feeling ‘dead’ when lying down or doing other activities on a mattress. It is also known for making it hard to roll over on the mattress since it creates a body shaped depression that takes some time to return to original shape. It is also known for not being very breathable, so that the person lying on the mattress gets hot from body heat or vapor that cannot escape. It does not have the amazing softness of latex foam (e.g., talalay latex foam rubber). Memory foam can also lack back support, since when the body heats up the memory foam, it becomes softer, and a body's heavy torso can sag into that softness. Memory foam does have positive properties, however, that latex foam lacks, the most significant of which is that memory foam is known for molding itself to the shape of the body over time, giving a more even support to the body (relief from pressure points). So, alternating layers of memory foam with layers of latex foam can be synergistic. The latex foam instantly tends to spring to shape, which would hasten the memory foam's return to shape after deformation, and would feel much more lively (as opposed to memory foam's deadness). Latex foam is more breathable, and the body's heat and vapors can escape through the intermittent latex foam layers. The softness of latex foam gives the mattress a much softer ‘hand feel’ to the mattress, and overcomes memory foam's initial hard feel which exists during the time when the memory foam is heating up to body temperature and slowly forming to the body. The latex foam's springy nature will help to offset the loss of support when the memory foam heats up and becomes softer. The alternating layers of memory foam add to the synergy by enhancing the shape-to-fit properties which reduces pressure points. These synergistic benefits combined with the benefit of local instability and general stability can yield a highly-desirable mattress or other foam cushion.
In some embodiments, a foam cushion can have more than two types of foams arranged in layers. Using the above example, layers of reticulated foam could be used with layers of memory foam and layers of latex foam to provide higher breathability. As another example, if more firmness is desired or if the spring-back to shape of the adjacent memory foam needs to be faster, a soft talalay latex in the above example can be replaced with a stiffer latex, generally made by the dunlop process rather than the talalay process. Although each layer 101 and 102 is represented as being formed from a single piece of foam, in some embodiments, a layer 101 or layer 102 could be formed from multiple pieces of the same foam.
A wide variety of foams could be used in embodiments of the present invention. The foams include, but are not limited to: quick-rebound polyurethane foam (selected from the group comprising conventional polyurethane foam, high resiliency polyurethane foam, and reticulated polyurethane foam), slow-rebound polyurethane foam (selected from the group comprising slower-rebound memory foam, quicker-rebound memory foam, and gel memory foam), latex foam (selected from the group comprising natural latex foam, organic natural latex foam, synthetic latex foam, and part natural part synthetic latex foam), expanded polyolefin foam, EVA foam, silicone foam, melamine foam, PVDF foam, polyethylene foam, shredded and then rebonded foam (comprising any shredded flexible foam types), Energex® foam (a unique foam made by Elite Comfort Solutions which is a highly breathable, somewhat viscoelastic foam that changes when warmed to body temperature from its original viscoelastic [memory] foam to a bouncy foam with resilience similar to latex), etc. Foams with different stiffnesses are intended to encompass, but not be limited to, using conventional polyurethane open-cell cushioning foams with stiffnesses of IFD (Indentation Force Deflection) 8, IFD 13, IFD 18, IFD 24, IFD 32, IFD 36, IFD 44, IFD 55, and IFD 60 or equivalents thereto. In embodiments of the present invention, either the type of foam may be different in one layer adjacent to the next, or the stiffness of the foam is different in one layer adjacent to the next, or both. Two or more types of foam can be selected for synergy of properties with the adjacent layer, and the two or more stiffnesses of foam may be selected to create stability under broad areas of the body or other cushioned object and instability under the pointy areas of the body or other cushioned object. Results can be more pronounced if the adjacent foams differ in both type and stiffness.
In both foam cushion 200 and foam cushion 300, gaps 103 form air pockets that can provide more breathability, less overall stiffness, less initial stiffness during the initial descent of the body or other cushioned object into the foam cushion, and reduced foam cost.
Non-rectangular foam cushions could also be created using the technique represented in
In foam cushion 1002, gaps 103 are only formed between layers 101 and base 102a. This may be accomplished by configuring layers 102 to have a greater height than layers 101 such that, even with layers 101 fully inserted between layers 102, gaps 103 will still be formed.
Foam cushion 1003 is similar to foam cushion 1002 except that gaps 103 are formed between layers 102 and base 101a. This may be accomplished by configuring layers 101 to have a greater height than layers 102 such that, even with layers 102 fully inserted between layers 101, gaps 103 will still be formed.
With each of the foam cushions formed of opposing foam cushion components, the type of foam for the top foam cushion component and for the bottom foam cushion component can be selected to provide one or more desired benefits. For example, the top foam cushion component can be formed of a more breathable foam than the bottom foam cushion component to enhance breathability. In contrast, the top foam cushion component could be formed of memory foam, which is less breathable, while the bottom foam cushion component could be formed of a more breathable foam. In such cases, the more breathable foam of the bottom foam cushion component can enhance the breathability of the less breathable foam of the top foam cushion component. This may be because the layers of the bottom foam cushion component extend up towards and are positioned close to the base of the top foam cushion component, so that heat does not need to convect very far through the less breathable foam to reach the more breathable foam.
Although
In some embodiments, a lubricant may be used during the process of assembling foam cushion components. For example, the ends (whether or not rounded) of layers 101 and 102 may be coated with a lubricant to facilitate insertion of the layers between one another. In embodiments where an adhesive is used, the lubricant could be added to the adhesive and then the mixture of adhesive and lubricant can be applied to the ends of the layers 101 and 102. In some embodiments, the adhesive could be water based (e.g., Simalfa 350) and the lubricant could also be water based (e.g., KY Jelly). In some embodiments, the mixture adhesive and lubricant could include 10% lubricant by volume, 20% lubricant by volume, or 50% lubricant by volume. In some embodiments, the lubricant may reduce the rate of evaporation of the adhesive and may therefore prolong the working time of the adhesive (i.e., the lubricant may slow the drying of the adhesive). This may particularly beneficial for assembling foam cushion components, such as foam cushion components 1511 and 1521, which can require a substantial amount of time to perform the zippering.
In embodiments in which glue (or other adhesive) is used to couple layers together, instability of the layers may be controlled by applying glue only at or near the tops and/or bottoms of the layers as opposed to along the full interface between the layers. In this way, layers that are intended to be unstable (e.g., those with higher IFDs) can more easily collapse due to the reduced length along which they are coupled to the adjacent layer. As described above, this designed instability can cause a mattress (or other cushioning article) to give in response to substantial pressure (e.g., at the hip or shoulder) while the remainder of the mattress provides firm support.
Various experiments were performed on the different types of foam cushions described herein and different configurations of such foam cushions. The results of these experiments are summarized below.
Various foam cushions matching the configuration shown in
Various foam cushions generally corresponding to the configurations shown in
Various mattresses generally corresponding to the configurations shown in
Various pillows generally corresponding to the configurations shown in
The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description.
This application claims the benefit of U.S. Provisional Appl. No. 63/342,223 which was filed on May 16, 2022.
Number | Date | Country | |
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63342223 | May 2022 | US |