Classifications

• • A—HUMAN NECESSITIES
  • A43—FOOTWEAR
  • A43B—CHARACTERISTIC FEATURES OF FOOTWEAR; PARTS OF FOOTWEAR
  • A43B13/00—Soles; Sole-and-heel integral units
  • A43B13/38—Built-in insoles joined to uppers during the manufacturing process, e.g. structural insoles; Insoles glued to shoes during the manufacturing process
• • A—HUMAN NECESSITIES
  • A43—FOOTWEAR
  • A43B—CHARACTERISTIC FEATURES OF FOOTWEAR; PARTS OF FOOTWEAR
  • A43B13/00—Soles; Sole-and-heel integral units
  • A43B13/14—Soles; Sole-and-heel integral units characterised by the constructive form
  • A43B13/18—Resilient soles
  • A43B13/187—Resiliency achieved by the features of the material, e.g. foam, non liquid materials
  • A43B13/188—Differential cushioning regions
• • A—HUMAN NECESSITIES
  • A43—FOOTWEAR
  • A43B—CHARACTERISTIC FEATURES OF FOOTWEAR; PARTS OF FOOTWEAR
  • A43B13/00—Soles; Sole-and-heel integral units
  • A43B13/02—Soles; Sole-and-heel integral units characterised by the material
  • A43B13/04—Plastics, rubber or vulcanised fibre
• • A—HUMAN NECESSITIES
  • A43—FOOTWEAR
  • A43B—CHARACTERISTIC FEATURES OF FOOTWEAR; PARTS OF FOOTWEAR
  • A43B13/00—Soles; Sole-and-heel integral units
  • A43B13/02—Soles; Sole-and-heel integral units characterised by the material
  • A43B13/12—Soles with several layers of different materials
• • A—HUMAN NECESSITIES
  • A43—FOOTWEAR
  • A43B—CHARACTERISTIC FEATURES OF FOOTWEAR; PARTS OF FOOTWEAR
  • A43B13/00—Soles; Sole-and-heel integral units
  • A43B13/14—Soles; Sole-and-heel integral units characterised by the constructive form
  • A43B13/18—Resilient soles
  • A43B13/181—Resiliency achieved by the structure of the sole
  • A43B13/186—Differential cushioning region, e.g. cushioning located under the ball of the foot
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
  • B29C44/02—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles for articles of definite length, i.e. discrete articles
  • B29C44/12—Incorporating or moulding on preformed parts, e.g. inserts or reinforcements
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
  • B29D35/00—Producing footwear
  • B29D35/0054—Producing footwear by compression moulding, vulcanising or the like; Apparatus therefor
  • B29D35/0063—Moulds
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
  • B29D35/00—Producing footwear
  • B29D35/12—Producing parts thereof, e.g. soles, heels, uppers, by a moulding technique
  • B29D35/122—Soles

Definitions

• Embodiments herein relate generally to the field of footwear, and more particularly to components of performance footwear, such as midsoles, as well as methods of making midsoles.
• the sole assembly of athletic footwear generally has a layered
• the midsole imparts cushioning and helps control foot motion.
• the midsole may be formed from a single-layer polymer foam that extends throughout the length and width of the footwear. With the exception of a difference in thickness between the heel and forefoot areas of the footwear, such a unitary midsole has substantially uniform properties.
• some conventional midsoles incorporate dual- or multi-density or multi-durometer polymer foams.
• the lateral side of the midsole may be formed from one foam material, and the medial side of the midsole may be formed from a second, less- compressible, denser foam material.
• the layers of foam are cut, placed, and glued together using a vertical or angled seam.
• This results in an undesirable lever effect during a footstrike as the weight of the foot travels over the abrupt transition point between foam densities or durometers.
• the sudden transition from firmer foam to softer foam (or visa versa) can result in instabilities in the footstrike, such as over-rapid pronation of the foot.
• this method of construction can require the use of glues that may contain volatile organic compounds (VOCs), which may have undesirable environmental and health impacts, both for the manufacturer of the footwear and the wearer.
• VOCs volatile organic compounds
• the use of a glued seam creates a potential site of physical failure, and the midsole layers may separate with use.
• Figures 1A, 1 B, 1C, 1 D, 1 E, and 1 F illustrate examples of multiple response property midsoles in accordance with various embodiments
• Figures 2A and 2B illustrate a method of making a multiple response property midsole, in accordance with various embodiments
• Figures 3A and 3B illustrate another method of making a multiple response property midsole, in accordance with various embodiments
• Figure 4 illustrates another method of making a multiple response property midsole, in accordance with various embodiments.
• Figure 5 illustrates another method of making a multiple response property midsole, in accordance with various embodiments.
• the description may use perspective-based descriptions such as up/down, back/front, and top/bottom. Such descriptions are merely used to facilitate the discussion and are not intended to restrict the application of disclosed embodiments.
• Coupled may mean that two or more elements are in direct physical contact. However, “coupled” may also mean that two or more elements are not in direct contact with each other, but yet still cooperate or interact with each other.
• a phrase in the form "A/B” or in the form “A and/or B” means (A), (B), or (A and B).
• a phrase in the form "at least one of A, B, and C” means (A), (B), (C), (A and B), (A and C), (B and C), or (A, B and C).
• a phrase in the form "(A)B” means (B) or (AB) that is, A is an optional element.
• Embodiments of the present disclosure are directed to performance footwear having portions that may help facilitate a more fluid foot movement, improve manufacturing and production techniques, and prevent injury to the foot, ankle, and/or legs during exercise, such as running, hiking, walking, and other impact-generating activities.
• multiple response property midsoles and/or portions of footwear are provided that may include strategically arranged multiple response property areas having blended transition zones disposed there between.
• the multiple response property areas (and the differences between them) may be characterized as having various properties, such as density, durometer, specific gravity, and other footwear design characteristics.
• the blended transition zones between adjacent response property areas may allow for a variety of biomechanical improvements, including, but not limited to, improved impact cushioning, support, and stability, as well as a more fluid footstrike motion.
• the term blended transition zone and any variation thereof may generally refer to the interlocking, intermingling, and/or intermixing of materials (e.g., foams) having different response properties (e.g., densities or durometers), such that there is not a definite, clearly defined linear or planar path between the materials with different response properties, but rather a gradual transition from one defined material/property to another.
• blending the transition zones in the midsole may help avoid the lever effect that is common when materials having different response properties are glued together, for instance with a vertical or angled seam.
• a denser or a higher durometer material is positioned directly against a less dense or lower durometer foam without a blended transition region, the foot may undergo an undesirably rapid and sudden pronation when it travels over the abrupt transition between densities.
• the blended transitions in the multiple response property midsoles disclosed herein may provide a gradual transition between the portions with different material response properties, which in-turn may help to ensure a more fluid footstrike motion.
• embodiments of the midsole may use a glueless construction method that effectively eliminates the VOCs present in the glues typically used to couple the different materials in a traditional midsole.
• Figure 1 A illustrates an example of a midsole with blended transitions between areas of differing (e.g., multiple) material response properties (e.g., density or durometer) in accordance with various embodiments.
• materials of different response properties have been strategically positioned in a posted configuration that may be useful in, for example, athletic shoes, to help control the rate of pronation.
• Midsole 100a may include different response property areas arranged from medial to lateral, with, for example, a higher density or durometer material disposed in the medial arch region, and transitioning to a less dense or softer material toward the lateral side of the midsole.
• a first response property material 10 may be located in the immediate arch area, with a second response property material 12 disposed immediately adjacent to (e.g., on the lateral side of) the first response property material 10.
• a blended transition 16 may be disposed between the first and second response property materials.
• a third response property material 14 may be positioned adjacent to the second response property material 12, and may generally comprise the rest of the midsole 100a.
• a blended transition area 18 may be disposed between the second and third response property materials.
• first response property material 10 may have a higher density or durometer, with second response property material 12 having a density or durometer that is less than that of first response property material 10, but greater than that of third response property material 14.
• Such a configuration may provide support and stability for a user who over-pronates during a stride, for example.
• the strategic alignment of the different material response properties and resulting blended transition zones may provide a midsole that may be useful in providing a combination of impact absorption, flexibility, and stability, for instance, for walking, jogging, comfort, cross-training, such as in running shoes, hiking boots, or trail shoes.
• Figure 1 B illustrates another example of a multiple response property midsole with blended transitions in accordance with various embodiments.
• a first response property material 10 may be located at the sides of the midfoot region of the midsole 100b, for instance generally in the medial arch region and opposite the arch region near the lateral edge of the foot.
• second response property material 12 may generally surround first response property material 10, with the remainder of the midsole comprising third response property material 14.
• blended transition zones 16 and 18 may be disposed between the different response property materials, 10, 12, and 14, and may contribute to the fluid motion, strength, and mechanics of midsole 100b.
• first response property material 10 may have a higher density or durometer than second response property material 12, which in turn may have a higher density or durometer than third response property material 14.
• this configuration may provide lateral stability, which may be useful, for instance, on rocky or uneven terrain, or for a user who is prone to either over-pronation or over- supination.
• this configuration also may provide enhanced flexibility, cushioning, and comfort in the heel and forefoot portions of the midsole.
• the strategic alignment of the different material response properties and resulting blended transition zones may provide a midsole that may be useful in providing a combination of impact absorption, flexibility, and stability, for instance, for jogging or running shoes, hiking boots, or trail shoes.
• Figure 1C illustrates another example of a multiple response property midsole with blended transitions in accordance with various embodiments.
• first response property material 10 may be located at the lateral and medial sides of the midfoot and the heel of midsole 100c, for instance generally in a
• second response property material 12 may generally surround first response property material 10
• third response property material 14 may comprise the rest of the midsole.
• blended transition zones 16 and 18 may be disposed between the different response property materials, and may contribute to the fluid motion, strength, and mechanics of the midsole.
• first response property material 10 may be of a higher density or durometer than second response property material 12 and third response property material 14, which may provide stability in the side and rear areas of the foot. This may be useful, for instance, on rocky or uneven terrain, while providing enhanced pronation/supination prevention, enhanced flexibility, and cushioning and comfort in the central and forefoot regions of the midsole.
• the strategic alignment of the different response property materials and resulting blended transition zones may provide a midsole that may be useful in providing stability, for instance, for hiking boots or trail shoes.
• Figure 1 D illustrates yet another multiple response property midsole 100d with blended transitions in accordance with various embodiments.
• the strategic placement of the different response property material areas may include arranging a first response property material 10 in the heel region, a second response property material 12 in the mid-foot region, and a third response property material 14 in the toe region, with blended transition zones 16 and 18 formed between the different response property material areas.
• Such an embodiment may be useful, for instance, in sandals where a higher density or durometer material may be used as the first response property material 10, for instance to improve impact absorbance of the heel region, support, and durability.
• the second response property material 12 may have a density or durometer less than that of the first response property, and may be positioned to provide additional support and cushioning for the midfoot area.
• the third response property material 14 may be the least dense of the three response property materials, and may be placed to provide enhanced comfort and flexibility in the forefoot region.
• Figure 1 E illustrates still another multiple response property midsole with blended transitions in accordance with various embodiments.
• different response property material areas may be arranged or layered vertically within the midsole 100e, from bottom to top.
• a layer of second response property material 12 may be sandwiched between first response property material 10 and third response property material 14.
• first blended transition 16 may be disposed between first response property layer 10 and second response property layer 12
• second blended transition zone 18 may be disposed between second response property layer 12 and third response property layer 14.
• the response properties may be selected such that a less dense or lower durometer (e.g., softer) third response property material 14 may be used as the upper layer to provide comfort, whereas second 12 and first 10 response property materials may have higher densities or durometers, for instance to provide durability, support and resilience.
• a less dense or lower durometer e.g., softer
• third response property material 14 may be used as the upper layer to provide comfort
• second 12 and first 10 response property materials may have higher densities or durometers, for instance to provide durability, support and resilience.
• Such an embodiment may be particularly useful in comfort shoes, work shoes, etc.
• Figure 1 F illustrates another example of a multiple response property midsole with blended transitions in accordance with various embodiments.
• midsole 100f may have multiple response property materials arranged to enhance lateral stability.
• lateral stability bars of first response property material 10 may be disposed at the medial and lateral edges of the midsole.
• the center portion of the midsole may include a third response property material 14, and second response property material 12 may be disposed there between.
• blended transition 16 may be disposed between first response property material 10 and second response property material 12, and second blended transition 18 may be disposed between second response property material 12 and third response property material 14.
• such an arrangement may provide a balance of cushioning (e.g., where third response property material 14 is a lower density or durometer foam) and stability (e.g., where first response property material 10 is a higher density or durometer foam).
• any number of response property areas may be used, for instance 2, 3, 4, 5, 6, or even more response property areas.
• Such different response property areas may be arranged in a number of strategic configurations.
• a low density or durometer material may be used wherever extra softness or cushioning is needed, such as in the forefoot area, heel layer, or upper layer of the midsole, or for use when the user has an injury or otherwise requires more cushioning.
• a higher density or durometer material may be included in any area requiring firm support, extra stability, or extra durability, such as in the arch region, the midfoot region, the heel region, or the lower portions of the midsole.
• the specific configuration of the midsole may be customized to suit the needs, footstrike pattern, or running style of an individual user.
• the blended transitions of the midsole may allow the shoe to respond to the individual needs of a particular user or the particular terrain conditions.
• the response property areas are referred to herein as low, medium, and high (e.g., as it relates to a material response property that is density or durometer), one of skill in the art will appreciate that these terms are relative.
• the material response property is durometer
• the low, medium, and high identifiers may correspond to 55, 60, and 65 Asker C; or 55, 65, and 75 Asker C. In other embodiments, greater or lower response property materials also may be used to suit the desired application.
• changing the material hardness of the midsole may change the activity in various lower extremity muscles, such as rectus femoris, biceps femoris, medial gastrocnemius, and tibialis anterior.
• the tibialis anterior muscle may exert significantly more force before the heel strike and less force following the heel strike than when running on a medium midsole.
• using shoes with a denser midsole may reduce the energy dissipated at the metatarsophalangeal joints and aid in improving jumping performances and economy of foot movement.
• the response may be varied in particular regions of the midsole and/or other portions of the footwear for a variety of reasons.
• Figures 1G and 1 H illustrate a multiple response property article of footwear in accordance with various embodiments, where the multiple response property materials comprise not only the midsole, but also portions of, for example, the heel cup 70 and/or upper 80.
• midsole 100g may also extend upward around the heel cup region 70, which may provide greater heel stability and/or protection.
• the strategic placement of the different response property material areas may include arranging a first response property material 10 in the heel region of the midsole, a second response property material 12 in the foot bed region of the midsole, and a third response property material 14 in heel cup region, with blended transition zones 16 and 18 formed between the different response property material areas.
• the multiple response property materials may extend to encompass all or a portion of the vamp or upper 80, such as the toe box, the instep, the tongue, or the ankle collar, or all or part of the insole or, outsole (not shown).
• the midsole material may extend around and/or over the instep, for instance to provide greater protection and stability through the midfoot region. In still other embodiments, the midsole material may extend around and/or over the forefoot region, for instance to provide protection to the toes. In some embodiments, the midsole material may extend around the entire foot and may form a part of or all of the footwear upper, for instance in boots or shoes that provide extra ankle support or foot protection. In some embodiments, the portion of the midsole material that extends past the midsole may include a less dense material, such as an extra soft response property material.
• methods of making a multiple response property midsoles and other footwear portions are provided.
• Conventional multiple response property midsoles are typically constructed by stock-fitting or gluing together individual material components prior to final molding or after final molding. This leaves a distinct line and a generally solid border between the different response property materials, which border is often delineated by a glue seam.
• the disclosed methods may allow the different response property material areas to have blended transition zones, which again may produce a more fluid, gradual change in the midsole response property as detected by the foot.
• the different response properties may be achieved by a variety of materials suitable for midsole construction. In some embodiments, the different response properties may be achieved by a variety of materials suitable for midsole construction. In some embodiments, the materials suitable for midsole construction.
• polymer foam pellets may be arranged such that compression molding of the pellets may result in blending of the different response properties in the transition zones, as illustrated in the examples shown in Figures 1A-1 H.
• the polymer foam pellets may be ethylene vinyl acetate (EVA) pellets.
• EVA is a polymer that may approach elastomeric materials in softness and flexibility, yet may be processed like other thermoplastics. The material has good clarity and gloss, barrier properties, low-temperature toughness, stress-crack resistance, hot-melt adhesive waterproof properties, and resistance to UV radiation.
• the midsole may include one or more other types of material, such as rubberized EVA, polyurethane, and/or any other midsole/footwear construction material known to those of skill in the art.
• the midsole may include only two different response property materials, whereas other embodiments may include four, five, six, or even more response property materials.
• these materials may be distributed about the midsole wherever a particular response property is desired.
• more or less of the midsole may comprise higher density or durometer foams than in the illustrated examples.
• lower or higher density or durometer materials may be incorporated under the metatarsals, for instance, to form crash pads.
• multiple response property midsoles with blended transition areas may be formed in a number of ways, for example using known midsole forming techniques, such as pre-form and compression molding, injection molding, pellet pour, and the like.
• the midsole may be formed by arranging foam pellets of different response properties in a specifically designed jig.
• a jig 200 having one or more compartments may be positioned within a midsole mold 50.
• EVA or other midsole forming pellets may be poured into the compartments 20, 21 of jig 200, as well as into a space 22 created between jig 200 and mold 50.
• a jig with two different compartments may allow for the midsole to be formed using pellets 24, 26, 28 of three different response properties, although other jig configurations are contemplated that have more or fewer compartments.
• the different response properties of pellets 24, 26, 28 may be color-coded for visual determination and placement in the proper compartments 20, 21 , 22 of the jig 200.
• the jig 200 may then be removed by lifting in a vertical direction, thereby allowing the pellets 24, 26, 28 to intermingle, or at least providing the potential to intermingle during the midsole formation process.
• the strategically positioned pellets 24, 26, 28 in the mold may then be subjected to a pre-form process, which includes addition of heat and temperature to activate the blowing agent in, for example, the EVA to induce the intended properties.
• blended transition zones are formed by virtue of contiguity between the different pellets, which allows for some flow or migration of the differing response property materials between strategic response property zones.
• the blocker or pre-form may then be compression molded, giving the midsole its final dimensions.
• blended transition zones formed during the preform and molding process may result in a mechanical coupling of the different response property areas without using an adhesive.
• the absence of harsh, inflexible lines/seams between traditional multi-density midsoles may provide a more fluid and gradual tactile feel as the foot naturally pronates during the running or walking motion.
• different colors may be chosen for the different response property pellets 24, 26, 28, which may allow for the blended transition zones to be visually distinguishable, and which may also give the final midsole a unique look.
• FIGS 3A and 3B illustrate side and top views of an example of another method for forming midsoles in accordance with various embodiments.
• a cage 300 may be inserted into mold 50, and may be configured to separate different response property pellets.
• cage 300 may surround second response property pellets 36, and may separate them from first response property pellets 34 and third response property pellets 38.
• cage 300 may be generally shaped like jig 200 in the previous
• the cage may be configured to melt during the pre-form formation stage, thereby allowing the cage material to integrate with and become part of the midsole.
• the melting of cage 300 may allow different response property pellets 34, 36, 38 to intermingle at the cage borders and form blended transition zones between differing response property material areas.
• the blocker or pre-form may then be compression molded, giving the midsole its final dimensions.
• Figure 4 illustrates an example of another method for forming midsoles in accordance with various embodiments.
• a quantity of pellets of each desired response property may be lightly molded prior to the pre-form stage, thereby forming one or more pre-molds 44, 46, 48, of a material that will achieve a desired response property.
• One or more different pre-molds 44, 46, 48 may then be placed within the mold 50 in the desired configuration.
• the pre-mold does not significantly change the pellet characteristics, but only temporarily holds like response property pellets in a desired configuration for placement in the mold, during the pre-form process the pellets/materials may still flow into adjacent response property materials, and thereby form the blended transition zones.
• the pre-molds 44, 46, 48 may be formed in a variety of ways.
• the pre-mold may include gently and briefly heating certain response property foam pellets in an individual mold such that that the pellets adhere to one another to form the desired pre-form shape.
• the pellets may be heated to approximately 130 ° C for about 4 minutes, and then cooled prior to placement in the pre-form mold.
• slight pressure may be added to ensure that a one-piece formation of the pre-form is achieved.
• a binder may be used to hold the response property material pellets together for strategic placement in the mold. The binder may be selected such that it may mix with the multiple response property materials during the pre-form process, similar to the aforementioned cage embodiments where the cage material is selected to melt and integrate with the pre-form.
• the pre-molds 44, 46, 48 may be placed in the preform mold, for instance, with a higher response property pre-mold 44 in the medial arch position, and with a medium response property pre-mold 46 sandwiched between the higher response property pre-mold 44 and the low response property pre-mold 48, which may be placed in the lateral position.
• the pre-molds 44, 46, 48 may then undergo the pre-form treatment and allow the different response property materials to intermingle and form the blended transition zones.
• the blocker or pre-form may then be compression molded, giving the midsole its final dimensions.
• Figure 5 illustrates yet another example method for forming midsoles in accordance with various embodiments.
• a single pre-mold 46 may be positioned within the pre-form mold in order to control placement of other lose pellets 54 and 58 having different response properties.
• the pre-mold 46 may be made from a second or a medium- response property pellet, and may be positioned within the pre-form mold such that it creates one or more partitions within the pre-form mold.
• Pellets 54 and 58 of different response properties may be disposed in the areas adjacent to the pre-mold.
• the different response property materials may intermingle to thereby form a blended transition zone.
• the blocker or pre-form may then be compression molded, giving the midsole its final dimensions.
• midsoles having three distinct response property materials illustrate methods of making midsoles having three distinct response property materials
• the methods may be adapted for making midsoles that may include only two different response property materials, or midsoles that may include four, five, six, or even more response property materials.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• Footwear And Its Accessory, Manufacturing Method And Apparatuses (AREA)

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• 2011
  • 2011-05-18 CA CA2800346A patent/CA2800346A1/en not_active Abandoned
  • 2011-05-18 JP JP2013511346A patent/JP5490316B2/ja not_active Expired - Fee Related
  • 2011-05-18 EP EP11784204A patent/EP2571389A2/en not_active Withdrawn
  • 2011-05-18 WO PCT/US2011/037062 patent/WO2011146665A2/en active Application Filing
  • 2011-05-18 CN CN201180024197.7A patent/CN102970891B/zh not_active Expired - Fee Related
  • 2011-05-18 US US13/110,876 patent/US20110283560A1/en not_active Abandoned
  • 2011-05-18 KR KR1020127032896A patent/KR101482833B1/ko not_active IP Right Cessation

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