MODULAR FOOTBED ASSEMBLIES AND METHOD OF MANUFACTURING SAME

An arch cookie includes a heel portion, a pair of arch supports extending from the heel portion toward a toe region, the pair of arch supports being of unequal length, the heel portion and the pair of arch supports being continuous, and at least one window disposed in at least one of the heel portion and the pair of arch supports.

FIELD OF THE DISCLOSURE

The present disclosure generally relates to footbeds used in footwear and used with footwear of all types including casual, dress, work, and athletic footwear. More specifically, the present disclosure relates to modular footbeds that provide superior comfort and performance and methods of manufacturing same.

BACKGROUND OF THE DISCLOSURE

Footbeds (also commonly referred to as sockliners or insoles) are a common component of many types of footwear with a large variation in design, shape, materials, cost, and overall quality. Much of this variation exists between footwear categories and footwear brands to adapt the design of the footbed into the design of the shoe, the intended consumer (athlete, casual, etc.), and price point of the footwear product.

Footbeds are a primary source of comfort and function in footwear as they are in direct contact with the plantar surface of the foot where high loads and pressures are realized. Typically, footbeds are made from a relatively thin (3.0-5.0 mm) layer of foam topped by a thin polyester fabric (top cover) that is adhered to the foam.

The footbed is often a flat piece of foam that does not provide sufficient cushioning, pressure reduction, and support for the foot. Footbeds that are molded only from inexpensive foam will quickly breakdown and take a compression set. This compression set changes the shape of the footbed and reduces the cushioning capability by as much as 75%, thus effecting overall comfort and support for the foot. Additionally, standard insoles provide inferior performance due to variance in foot shapes and sizes. Conversely, co-molded insoles are often expensive to manufacture.

SUMMARY OF THE DISCLOSURE

In at least some examples, an arch cookie includes a heel portion, a pair of arch supports extending from the heel portion toward a toe region, the pair of arch supports being of unequal length, the heel portion and the pair of arch supports being continuous, and at least one window disposed in at least one of the heel portion and the pair of arch supports.

Various embodiments of the present invention will now be described with reference the appended drawings. It is to be appreciated that these drawings depict only some embodiments of the invention and are therefore not to be considered limiting of its scope.

DETAILED DESCRIPTION

Despite the various improvements that have been made to footwear and their methods of manufacture, conventional devices suffer from some shortcomings as described above.

Footbeds may include a shape in the top surface that attempts to match the contours of the foot. These footbeds can be made with more durable materials such as polyurethane foams and support structures made with composite materials such as injected plastics and carbon fiber so the footbed shape is maintained. Footbeds from corporations such as Spenco Medical Corp. and Superfeet Worldwide are examples.

Higher quality materials may be used to produce such footbeds, including materials that are more durable, stiffer, and shaped to match the foot. It should be understood that using more durable, higher quality materials will reduce the breakdown of materials and maintain the like-new performance.

A footbed for an article of footwear that demonstrates an ideal geometry for comfort, foot control and stability, and ambulatory efficiency is disclosed in U.S. Pat. No. 10,653,204, the disclosure of which is hereby incorporated by reference in its entirety. The footbed described in the '204 patent is the result of extensive research, development, and mathematical modeling of thousands of human feet. Footbeds using the geometry disclosed in the '204 patent provide excellent performance in stability and comfort, and the use of a large number of human subjects contributing to the scanned data ensure that footbed represents an ideal geometry for the majority of the population.

Conventional footbeds including certain one disclosed in the '204 patent are typically co-molded composites of foam and semi-rigid plastic. The co-molding process of joining foams and semi-rigid plastics are produced at a price point that might be too expensive for certain shoe models. Specifically, each size of footbed in a size run requires separate molds for the semi-rigid plastic and the mating foam. The cost of these molds is then passed to the consumer in the cost of the footbed. Co-molding of footbeds similar to footbeds described in the '204 patent also adds cost and complexity to the footwear manufacturer. An article of footwear with an expensive footbed requires a certain cost structure for the entire shoe and predisposes a price point, sales volume requirement, and capital allocation for molds.

Conversely, less expensive articles of footwear utilize inexpensive components such as the footbed. This often means that the footbed is made from a single sheet of non-molded foam typically known as sheet stock foam. Sheet stock foams are usually homogeneous with a constant thickness. While they are less expensive, they do not provide the comfort and stability produced when using a molded footbed made from composite materials.

Thus, it would be beneficial to provide a footbed that delivers the comfort and stability features of footbeds created with co-molded methods as described in the '204 patent, but at lower price points and/or with greater flexibility in supply planning and mold cost allocation. Such products may allow for even greater flexibility of comfort, stability, cost, supply planning, and mold cost allocation by allowing the footwear manufacture to choose the final selection of footbed features and costs when the shoe manufacturing is close to completion and with flexible product supply planning.

Therefore, there is a need for further improvements to the devices, systems, and methods of forming footbeds. Among other advantages, the present disclosure may address one or more of these needs.

In some embodiments, a footbed10includes a foam layer20that runs the length of the footbed10from toe to heel, with a rigid or semi-rigid heel plate30attached to the full-length foam20and extending from the rear part of the footbed10to a point in the midfoot R2as shown inFIGS. 1 and 2. The midfoot R2point may be proximal to the position of first and fifth metatarsal heads of the foot. The heel plate30has a geometry designed to provide support and comfort to the heel and midfoot R2region of the foot by improving cushioning and reducing pressure on the plantar foot surface.

The shape resembles the shape of the plantar surface of the foot. The rigidity of the heel plate30helps maintain the shape of the geometry. In the forefoot R3and toe region of the footbed10a non-slip material50is adhered to the lower portion of the full-length foam20to add rigidity to the foam to keep the foam from wrinkling during use. Additionally, the non-slip material50keeps the footbed10from slipping forward in the shoe by adding friction between the footbed10and lasting board of the shoe. Ideally, the heel plate30includes a cutout80on the bottom of the heel plate that allows the full-length foam to protrude70through the semi-rigid heel plate such that the foam is in contact with the shoe's lasting board providing shock absorption. Additionally, the foam protruding70through the heel plate will add friction between the shoe's lasting board and the footbed10providing additional friction and aid in keeping the footbed10from moving during use. The protruding foam70, due to its compliance, also supplies additional shock absorption as the foam70compresses during loading prior to the semi-rigid heel plate30contacting the lasting board.

Some of the components of a footbed according to this disclosure are shown inFIGS. 1 and 2, and the following nomenclature may be used throughout the specification to describe some of these components:

The footbed base20may be made from a resilient foam material produced with techniques such as injection or compression molding and made from materials such as foamed polyurethane or foamed ethylvinyl acetate (EVA). Additional and less common foams known to the industry such as foamed rubber or Polyethelene (PE) foam may also be used. The foam is typically of a specific gravity (SG) ranging from 0.15-0.40 with a material hardness between 15 & 50 on the asker C scale. These types of foams are common in the footwear industry and known to provide quality cushioning and comfort characteristics to the wearer. The footbed base20is of a relatively consistent thickness throughout the footbed10with thicker sections in the midfoot R2to accommodate the arch area40and shaped to match the plantar foot surface. The heel plate30is made from a material that is more rigid than the foam20used for the footbed base20and is commonly made from a plastic material that is produced via injection or compression molding techniques. Plastics used for the heel plate30may include nylon, polyurethane, EVA, polycarbonate, and peebax. These plastics have a specific gravity in the range of 1.0-1.2 and when molded with the above techniques have a hardness of 50-90 on the shore A scale. Composites such as carbon fiber may also be used with physical characteristics similar to the plastics mentioned above.

The heel plate30is adhered to the bottom surface of the footbed base20in the heel region R3and the non-slip material50is adhered to the bottom surface of the footbed base20in the forefoot R1region of the footbed10. The materials may be adhered to each other using adhesives known in the industry or by co-molding the materials via heat and pressure that effectively melts the outer layer of each material to the other.

The heel plate30provides the primary shape of the footbed10with a stiffness and materials that resists long term deformation. The heel plate30is attached to the footbed base foam20using standard adhesives known in the industry. With the footbed base20foam adhered to the heel plate30, the foam takes the shape of the heel plate30and thus has the optimized geometry to match the plantar foot surface. The heel plate is adhered to and positioned on the footbed base20from a point furthest in the heel to a point in the midfoot R2that is proximal to the 1stand 5thmetatarsal heads of the foot to ensure comfort and compliance at the bending joints of the foot.

The contours of the heel plate30that provide the primary shape of the footbed10are critical for comfort and support of the foot. Areas within this shape that are significant to the function of the footbed10include the heel cup depth, heel cup diameter, medial heel cup wall angle, lateral heel cup wall angle, rear heel cup wall angle, medial heel cup wall height, lateral heel cup wall height, rear heel cup wall height, arch height, and arch spring.

In at least some examples, a modular system may be used to form the footbed and improve product planning, costs, and configurability. Such footbeds may enable the manufacturer to delay the supply planning of footbeds and selectively choose the footbed configuration for the appropriate article of footwear (and its price point) without making changes to the cost structure and manufacturing methods of the footbed. This allows manufacturers to utilize one component stream of footbeds for multiple shoes styles and price points, thereby, enhancing supply efficiencies and component flexibility when creating an article of footwear.

In at least some examples, the efficiencies described in the above paragraph are created by utilizing two separate manufacturing streams. A first stream of manufacturing may be used to create an arch cookie including a semi-rigid heel cup and arch of various shapes and/or sizes using, for example, the techniques described in the '204 patent. The term “arch cookie” may be used herein to include a semi-rigid component. The term “semi-rigid” may include suitable materials that are tested for flexural modulus through ASTM D790. In at least some examples, “semi-rigid” includes materials having a flexural modulus in the range of 0.01 to 4.50 GPa. The arch cookie may include at least a portion of the heel cup and at least a portion of an arch. A second stream of manufacturing creates the molded foam that forms the top portion of the footbed. One familiar with the art of footwear manufacturing will understand that selectively choosing to include or exclude the semi-rigid heel cup and arch of a footbed will vary the overall cost of the footbed. Specifically, excluding a material from a footbed will reduce the total volume of material, thereby affecting the volume of the footbed and the fit of the interior portion of the shoes that accepts a user's foot. Described below are the unique methods and features that allow this footbed to be constructed with or without a semi-rigid arch and heel cup without having a negative effect on overall fit and comfort. The option of including a heel cup and arch support can be made at any point during the design, development, or supply planning steps. The choice can also be made by the consumer at the time of purchase or during use by coupling and decoupling the arch cookie from the footbed foam to meet their desired comfort needs.

A semi-rigid arch cookie may be made from common molding materials and techniques such as carbon fiber, plastics, and other composites and combined with foam polymers such as EVA or polyurethane to form a footbed structure that may enhance the comfort, ambulatory efficiency, and stability of a user when the footbed assembly is used in an article of footwear.

Those skilled in the art of footwear manufacturing, biomechanics, orthopedic medicine, and podiatry may agree on the optimal materials and geometry of a footbed included in an article of footwear. However, the marketplace may have concerns and constraints with cost, materials, and features and benefits of shoes for different brands. For this reason, a flexible process that allows for variations in quality and construction of components would be beneficial. Moreover, individual tastes, styles, price to quality, and functional requirements can vary widely with consumers.

FIGS. 3-7show examples of modular footbeds according to embodiments of the present disclosure. Said footbed assemblies provide flexible features, benefits, and cost by allowing the coupling and decoupling of a semi-rigid arch cookie from a foam layer. The main body of the footbed is designed to accept a detachable, semi-rigid arch cookie such that it works effectively if the semi-rigid arch cookie is coupled to the footbed main body or if the arch cookie is removed. One skilled in the art will appreciate that certain measurements, volumes, and tolerances may be achieved in order for the footbed to work effectively. These specific geometries and tolerances may be achieved whether or not the semi-rigid arch and heel cup is included.

FIG. 3is a view of the dorsal surface of the footbed and, therefore, shows the surface that interacts with the lasting board of an article of footwear. The opposing surface (not shown) interacts with the foot and generally follows the shape of the plantar surface of the foot. The footwear assembly300shows a footbed with a full-length elastomeric foam330and a semi-rigid arch cookie360. Arch cookie360may include arch portions362a,362band a heel cup364. Arch portions362a,362bmay be in the form of lateral branches that extend from the heel cup toward the toes. In the example shown, arch portion362ais longer than arch portion362b. The three components (i.e., heel cup and two arch portions) may be continuous, but it will be understood that the three components may also be discontinuous and that the three components may be separately attached to a foam layer. In some examples, the arch cookie is configured and arranged to support the first metatarsal, extend down toward the longitudinal arch, curve to provide an extended heel support designed to wrap around the calcaneus pad.

In one example, semi-rigid arch cookie360is positioned under the medial arch and wraps around the heel to the lateral side of the footbed300. The arch cookie360may include one or more voids or windows350that allow the elastomeric foam330to protrude through the window. The size and position of the cut-out thru-window350can be designed to provide different levels of comfort and support. It also provides visual appeal for the user and reduces the weight of footbed assembly300. One can appreciate that one skilled in the art may determine different configurations where the size, shape, and position of the cut out thru-window350is varied to achieve different results. A semi-rigid guitar pick feature370may also be disposed adjacent the heel, the arch cookie360being configured to wrap around the guitar pick feature.

FIG. 4is a detailed bottom view of a semi-rigid arch cookie360with a single cutout thru-window350. The single cut out thru-window350in the area of the medial arch allows for the polymer elastomeric footbed foam330to protrude through the cutout thru-window350. The semi-rigid arch cookie360may be manufactured from various plastics and composites that can be molded via injection molding or heat forming. In at least some examples, the arch cookie may be formed using additive manufacturing techniques (e.g., 3D printing or the like). In at least some examples, the arch cookie is bespoke (i.e., it is custom produced and tailored to a particular individual). Alternatively, the geometry of the arch cookie is formed based on a selection of scans from a population, and the shape (e.g., length, width, thickness, profile, curvatures, etc.) is selected at least partly based on the methods and techniques of U.S. Pat. No. 10,653,204, which are incorporated by reference herein. For example, the arch cookie geometry may be based at least partly on one or more of the seven representative measurements described in the '204 patent.

The semi-rigid arch cookie360may have the same or a higher modulus/stiffness than the polymer elastomeric foam330. Specifically, foam330may have an ASKER C Hardness in the range of 8 to 50, while arch cookie360may have a flexural modulus in the range of 0.01 to 4.5 GPa per ASTM D790.

The semi-rigid arch cookie360and footbed polymer elastomeric foam330components may be permanently molded together with various co-molding processes. If it is desired, a non-permanent attachment may be achieved by using a non-permanent method such as an adhesive sticker (peel-and-stick) or hook-and-loop attachment. A permanent attachment may also be achieved by using a permanent adhesive, such as cement.

FIG. 5is a footbed assembly500constructed from a polymer and elastomeric foam530and a semi-rigid arch cookie560. Arch cookie560is similar to arch cookie360and includes a pair of arch portions562a,562band a heel portion564, but it includes a large number of cut-outs or windows550. As shown, the windows550are disposed in both arch portions562a,562band heel portion564. It will be understood, however, that the windows may be limited to any one or two of the three portions, or to none of them.

The multiple cut-out thru windows550may allow the footbed to be used in two different configurations. In the first configuration the polymer elastomeric footbed foam is joined together with the semi-rigid arch cookie560. The arch cookie560may provide additional structure, support, and comfort to the wearer. The two components can be joined with common non-permanent adhesives commonly used with “peel-and-stick” applications. This “peel-and-stick” mechanism allows for either the user or manufacturer to choose the desired configuration depending on factors such as cost and personal preference. If the wearer or manufacturer decides to omit the semi-rigid arch cookie560the footbed consisting of only the polymer elastomeric foam530is placed in the article of footwear. The multiple cut-out thru-windows550of the arch cookie560associated design of the polymer elastomeric footbed foam530make it possible for the footbed to fit properly into the article of footwear without changing the internal volume of the article of footwear and thereby keeping the fit consistent. In some examples, the foam530has a number of complementary protrusions531that align with windows550of arch cookie460. Each of protrusions531may be complementary to one of the windows. That is, each of the protrusions may have a shape and/or size that is equal or similar to one of the windows, and that aligns with that window. When the protrusions531extend through the complementary windows550they provide interlocking between the two components to better secure them together. In at least some examples, the length of the protrusions is equal to the length of the window so that the bottom of the secured assembly sits flush with the bottom of a shoe.

FIG. 6is a bottom view of the arch cookie560having windows550. This component may be manufactured using various materials and manufacturing processes commonly used to mold shapes into semi-rigid forms. Molding processes include injection molding, heat forming, carbon fiber layup, and 3D printing. Numerous plastics and composite materials may be used including polymer plastics such as polyurethane, EVA, Nylon, carbon fibers, and other materials suited for this construction. The multiple cut-out thru-windows550are positioned to allow the footbeds polymer, elastomeric foam530to pass through as protrusions531via the cutout thru-windows550. This configuration allows for a consistent positioning and fit into the shoe cavity. Including the semi-rigid arch cookie via adhesive (permanent or non-permanent) may provide additional support and comfort but will not alter the position and, therefore, fit of the footbed in the shoe cavity.

FIG. 7is a lateral view of the footbed assembly500having an arch cookie560and a foam530. Arch cookie560includes multiple windows550as previously described. The multiple thru windows550allow the polymer elastomeric foam530to protrude through at certain protrusions531and interact with the shoe's lasting board. This feature means that the footbed may be positioned consistently in the shoe cavity with or without the presence of the arch cookie.

FIG. 8is a schematic illustration of one example of a footbed assembly800having an arch cookie860with windows850, and a foam830having protrusions831. As shown in the cross-sectional views ofFIGS. 9A-Ccertain techniques may be used to couple the foam to the arch cookie. Specifically, a mechanical interlock may be formed between the foam and the plastic/composite arch cookie. In the embodiment shown inFIG. 9A, the interlocking is shown between the foam930and the arch cookie930. In some variations, the foam pillars930athat protrude through the arch cookie960may have a shape to enhance the locking of the two components. This may be used in addition to, or instead of, a semi-permanent adhesive and/or hook-and-loop attachment.

InFIG. 9B, the foam pillar930aof the foam may have a negative draft angle that keeps the arch cookie960aup against the base of the footbed. Alternatively, as shown inFIG. 9C, the pillar930bincludes a notch with a widened base so that the arch cookie960bsnaps in to once it has been pushed on to the pillars. The plastic arch cookie would be molded accordingly to fit the foam pillar and enhance the mechanical lock. In some examples, the mechanical lock may be installed and/or replaced by the user. In some examples, a kit is sold including a foam base and a plurality of arch cookies of different stiffnesses, and the user may select the arch cookie that provides them with the desired performance (e.g., comfort, support, etc.). In at least some examples, the user may choose the appropriate arch cookie or no arch cookie at all to obtain the performance and/or stiffness they desire. In these examples, it will be understood that the arch cookies may be of similar shapes, sizes and/or geometries may vary, for example, only in stiffness. Additionally, due to the geometry of the foam, the fit and/or volume of the footbed inside a shoe may be kept substantially similar or constant with any of the available arch cookies or without an arch cookie at all.

Described above is a design and method of creating flexible manufacturing and wearer options for footbeds similar to ones described in the '204 patent. This flexible configuration allows for the user or manufacturer to selectively choose to use a semi-rigid arch and heel cup. The arch cookie may be joined to the polymer footbed foam via adhesives similar to ones used in “peel-and-stick” situations and give footwear brands and consumers more choices when deciding on final footbed configurations without altering manufacturing processes or internal shoe fit.