Spring-backed footwear insole
Patent Information
- Application Number
- PCT/US2026/015688
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2026-02-18
- Filing Date
- 2026-02-18
- Publication Date
- 2026-08-27
Smart Images
Figure US2026015688_27082026_PF_FP_ABST
Abstract
Description
SPRING-BACKED FOOTWEAR INSOLEINVENTORS MATTHEW GOOCH DANIEL WAKELAND LISA COLLANDER NICHOLAUS PERRYPRIORITY CL IM
[0001] This application claims benefit of U.S. Provisional Application No.63 / 760,034 entitled SPRING-BACKED FOOTWEAR INSOLE filed February 18, 2025. The entire content of which is incorporated herein by reference in its entirety.FIELD OF THE INVENTION
[0002] This application relates to insoles for footwear and, more particularly, to insoles to improve performance for various sports shoe applications.BACKGROUND OF THE INVENTION
[0003] Footwear insoles and orthotics may be used to improve comfort and support for a wearer. Insoles and orthotics may also be used to improve performance through arch and heel support, torsional stability, and comfort. An insole or orthotic may address foot shape including arch geometry, heel cupping, and even custom foot anomalies. These insoles may also provide extra padding for various activities. Such features can increase both comfort and performance by holding, cupping, and padding the foot. While conventional insoles often provide cushioning and / or support, they might not provide a spring response and stability specifically adapted for different users, footwear applications, and activities.SUMMARY OF THE INVENTION
[0004] In accordance with examples of the present disclosure, an insole for footwear includes a support structure and a cushion structure extending along the length of the insole, and further includes a spring plate secured beneath at least a portion of the cushion and / or support structure. The spring plate may be formed of a composite material and may be shaped to provide energy return and stability while permitting desired flexion in selected regions of the foot, including differential flex at the toe region. In some examples, the spring plate includes one or more slots that define regions of variable stiffness, such as a slot that permits differential flexing of a big-toe region relative to a remainder of the toe region. In some examples, a heel region of the spring plate is truncated or otherwise shaped to modify heel strike response, and may include a medial extension, a recess, or a forked heel configuration. In some examples, the insole further includes a cupping support member in the heel and archregions that overlaps a rearward end of the spring plate and may include an opening to receive a supplemental pad.
[0005] In one preferred embodiment The insole includes a top portion, a metatarsal portion, a mid-portion, and a heel portion. A cushion extends from the top portion of the insole to the heel portion. The cushion has a top surface and a bottom surface. A spring plate is preferably secured below the top surface of the cushion. The spring plate may extend from the top portion of the insult to at least the mid portion of the insole. The spring plate has at least one slot providing additional flex to portions of the spring plate and adjacent to the slot.
[0006] In one preferred embodiment the slot is disposed in a top portion of the spring plate, the slot separating the support provided by the top plate under the big toe region of a top portion of the plate from a remainder of the top portion of the plate. The plate may also include a rear end with a medial finger or flange on the medial side of the insole in the heel portion of the insole. The medial finger is preferably narrower than the remainder of the plate in the heel portion of the insole. The plate may also include a heel recess at the rear root end of the heel portion of the plate. The heel recess forms an inwardly curved shape in a lateral mid portion of the heel portion of the plate. In one preferred embodiment the big toe region of the plate is angled upwardly relative to a portion of the plate in the metatarsal region of the insole. The angle of the remaining top portion of the plate may also be likewise angled. In some embodiments the big toe region of the plate is angled between 5 and 20° relative to the metatarsal portion of the plate. However, the toe region in some embodiments may be flat or have other angles, depending on the user, the footwear, and the application. Preferably for a running shoe, for example, 10 degrees of ramp angle is preferred.25315
[0007] In another preferred aspect of the embodiments herein, the spring plate corresponding to a mid-portion of the insole includes positive camber as it extends along a portion of the longitudinal axis of the plate.
[0008] In another preferred embodiment one or more slots may be included along a lateral side of the spring plate in a metatarsal portion of the plate. These slots may extend laterally into the plate thus creating fingers that extend outwardly from the mid, continuous portion of the plate. In one embodiment A rearward end of the spring plate terminates at a midportion of the insole, forward of a heel portion of the insole.
[0009] In some such embodiments, a cupping support member may be provided that extends from the heel portion of the insole to the mid portion of the insole. The cupping support member preferably overlaps the rearward end of the spring plate in this embodiment. The cupping support member may include an opening under a mid-portion of the heel region of the insole. A supplemental pad may be secured within the opening.
[0010] In other preferred embodiments a slot may be provided in a heel portion of the spring plate, the slot creating a forked heel portion of the spring plate with a rarely extending medial arm and a rarely extending lateral arm. The spring plate may also include slots extending into the lateral side of the spring plate in the metatarsal portion of the spring plate, the slots creating at least one laterally extending finger. Slots may also be provided extending into the medial side of the spring plate in the metatarsal region of the spring plate, the slots creating at least one medially extending finger. The slot in the heel portion of the spring plate may extend at least to a mid-portion of the insole.
[0011] The disclosure herein also provides for an insole for placement in footwear above the midsole of the footwear. The insole includes toe metatarsal mid and heel regions. A25315cushion layer extends from the toe region of the insole to the heel region of the insole. The cushion layer has a top surface and a bottom surface. A spring plate is secured below the top surface of the cushion layer. The spring plate may be on the bottom of the cushion layer, within a recess in the cushion layer or nested within the cushion layer. The spring plate has a generally longitudinally extending slot in the toe region. The slot separates at least a portion of the big toe region of the spring plate from the remainder of the toe region of the spring plate.
[0012] Tn one embodiment disclosed herein, the spring plate secured below the top surface of the cushion layer extends from the toe region through the arch region of the insole. A cupping support member extends longitudinally across the heel region and the arch region of the insole. The cupping support member overlaps with the rearward end of the spring plate.
[0013] Each of these various preferred embodiments provides advantages for differing users applying the insole with the spring plate to differing footwear for differing applications. Thus, both comfort and performance advantages can be obtained through padding, cupping, support, stability, and energy return.25315 <BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Preferred and alternative examples of the present invention are described in detail below with reference to the following drawings:
[0015] Figure 1A shows a running shoe with a corresponding insole removed;
[0016] Figure IB show s a bottom view of the insole of Figure 1A;
[0017] Figure 1C show s the spring plate isolated from the insole of Figure IB;
[0018] Figures ID and IE show bottom and side cross-sectional views of the insole of Figure 1A;
[0019] Figures IF through one Figure II show an exploded view of the parts that make up the preferred insole of Figure 1 A;
[0020] Figure 1J shows a cross section of the spring plate used on the bottom of the insole of Figure 1A;
[0021] Figure IK sho s a side elevational cross-sectional view of the insole;
[0022] Figures 2A and 2B show bottom and perspective views of an alternate insole;
[0023] Figure 3A illustrates a court shoe with a corresponding insole removed;
[0024] Figure 3B shows the insole by itself with a closer view of the features thereof;
[0025] Figures 3C through Figure 3G show an exploded view of the various parts of the insole of Figure 3 A;
[0026] Figure 4A shows a cleat footwear article with its corresponding insole removed:25315
[0027] Figure 4B is a bottom view of the insole of Figure 4A showing more detail; and
[0028] Figures 4C through 4 E show an exploded view of the insole of Figure 4A.DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] The following description is provided to illustrate examples of the invention and is not intended to limit the invention to the described examples. The terms “including,” “comprising,” and similar terms are used in an open-ended sense. For clarity, not all routine features of implementations are described. Applicant has numbered the figures and elements in the drawings such that those in the 100s are generally directed to a first embodiment, those in the 200s are directed to a second embodiment, etc. Like element / feature numbers in the 10s spot and the Is spot are like elements, although they might not be identical. Certainly, the features of the embodiments can be borrowed from one to another for other examples of devices that may fall within the disclosure and invention herein.
[0030] One preferred embodiment of the disclosure herein is shown in Figures 1 A through IK. A running shoe 100 is shown as an example of the athletic footwear that this particular insole 102 is adapted for. The running shoe 100 may include an outsole 104, a midsole 106, and an upper 108. The preferred embodiment discussed here applies to a standard running shoe but may be any shoe for such activities or related activities such as walking, jogging, or performance-oriented athletic training or competitive events. The insole provides improved comfort and performance for generally straight-line movement, while providing stability and impact protection at the heel and lateral sides of the insole. The insole is designed to complement the fit and performance characteristics of the running-type shoe. Such shoesmay have a thick midsole for shock absorption, minimal outer tread to keep weight to a minimum, average internal volume, and some stability support without heavy upper material. The insole 102 includes a toe portion 110, an arch portion 112, and a heel portion 114. These “portions” may be generally considered to be regions of the overall insole.
[0031] The insole includes a cushion layer 116 that extends from the front of the insole to the rear of the insole. A thin fabric layer 118 may be sandwiched on top of the cushion layer. Fabric layer 118 may include a breathable fabric or a non-breathable fabric. Fabric layer 118 may include a low friction surface in portions thereof for ease of insertion of the foot. Fabric layer 118 may also include an area of the top of the fabric with gripping portions such as a silicone material. Thus, the mid-portion of the fabric layer can slide while a metatarsal head portion can grip.
[0032] A spring plate 120 is secured preferably to the bottom of cushion 116 and does not extend the full length of cushion 116 in the preferred embodiments. Spring plate 120 is preferably a carbon composite plate, such as those provided by Carbitex®. Alternatively, spring plate 120 may be any other spring material that provides increased resistance as it bends, including metals, plastics, or other composites. In one preferred embodiment, the spring rate of spring plate 120 is constant in bending stiffness, while in other examples it may be nonconstant such as a progressive spring rate. The rate may also be decreasing. Preferably the plate stiffens as it bends upwardly, either at a constant rate or a progressive rate.
[0033] Figures IB and 1C provide further clarifying details of run insole 102. In this embodiment, spring 120 includes a heel portion 122, a mid-foot portion 124, a metatarsal head portion 126, and a toe portion 128. Toe portion 128 includes a separated big-toe portion 130. Big-toe portion 130 is separated from the remainder of toe portion 128 by a slot 132. Slot25315132 runs from a forward end of spring plate 120 to approximately the pivot joint of the wearer’s big toe. This configuration allows independent flexion of the first metatarsal joint. Spring plate 120 is wider in the metatarsal head portion 126 and the toe portion 128 than it is in the midfoot portion 124. Thus, the midfoot portion 124 allows some torsional flex while still providing some bending stiffness and arch camber support. As noted further herein, the lay-up angles of the fibers in the composite greatly affect the torsional and bending stiffnesses of the spring plate 120.
[0034] The cushion layer 116 is preferably formed with thermoplastic polyurethane (TPU). More specifically, a supercritical expanded TPU (ETPU) foam is preferable. The ETPU is a versatile material that provides excellent cushioning properties. It can also withstand high levels of wear and tear. The ETPU includes supercritical polyurethane beads that are injected into the mold with the TPU. These beads allow a thin-to-moderate overall thickness of the cushion layer while still providing good cushion. The use of these beads can be varied depending on the specific requirements of the user and the intended use of the footwear. Other materials with similar properties, such as silicone, latex, or other advanced polymers and supercritical foams, could also be used to form the cushion layer. The matrix that holds it together is preferably a poured polyurethane (PU). The preferred minimum thickness of the cushion layer 116 with supercritical beads is about 4mm. The beads in the matrix provide a textured surface that can project somewhat through the fabric layer 118. This texture can be advantageous for a run shoe application, providing a tactile feel to the runner.
[0035] The spring heel portion 122 of spring 120 preferably includes a heel strike extension or flange 134 that projects rearwardly on a medial side of the spring plate 120 from a wider portion of the spring heel portion 122. This flange 134 is specifically designed and25315intended to wrap around the base of the calcaneus (heel bone) to aid in the provision of stability and a smooth heel to toe transition. Thus, the heel strike extension 134 provides stability and impact absorption to the runner as heel strike occurs and the foot / shoe typically moves from slight supination to pronation with the lateral side of the heel striking and the foot slightly pronating as the stride continues onto the metatarsal head of the foot and to the final toe push where the exit force is mostly on the big toe (medial side of the foot). In preferred embodiments, a heel recess 136 is provided adjacent to the heel strike extension 134 along a central portion of the heel region 122 of the insole. This heel recess 136 is filled with additional cushion material from insole cushion 116 or from a separate inserted cushion plug to provide impact protection as well as shaping the heel region of plate 120 for stability as the heel strike and pronation occurs.
[0036] Figures ID and IE clarify additional details of the construction of run insole 102. The cross-sectional view in Figure IE shows the cushion recess 138 that is preferably provided at the bottom of cushion 116. Spring plate 120 is secured within cushion recess 138. In other embodiments, plate 120 could be secured to the bottom of cushion 116 without a recess. In other embodiments, spring plate 120 could be inserted and encapsulated, at least partially, within cushion 116. Also shown in Figure ID is the extra cushion material in the heel region 114 of run insole 102.
[0037] Figures IF through II illustrate an exploded view of the various preferred layers of run insole 102. Fabric layer 118 is a thin, preferably breathable material that extends the entire length and width of the top surface of run insole 102. A sub-foam layer 140 is disposed just beneath fabric layer 118. The sub-foam layer 140 may be a supercritical Expanded Thermoplastic Polyester Elastomer (ETPEE) foam. It is preferably laminated thereto25315but could alternatively be co-molded or otherwise secured. Sub-foam layer 140 may be an open-cell soft foam material to provide cushion and comfort to the foot of the user. A more rigid or more substantial base foam layer 142 is secured to the bottom of sub-foam layer 140, such as by lamination with an adhesive. Base foam layer 142 may be a closed-cell foam to provide more support for the arch and heel while supplying progressive cushioning for the foot of the wearer. In the preferred embodiment, base foam layer 142 is an ETPU, as noted above. Various levels of support can be provided depending on the foam used. For example, an insole for a heavier user may advantageously be provided with a denser foam (or at least stiffer foam) for adequate heel and arch support whereas a lighter user may benefit from lighter density or at least less-stiff foam. Spring plate 120 is secured to the bottom of base foam layer 142 and is configured as discussed above.
[0038] Figures 1 J and IK show a preferred side profile of spring plate 120 that may be employed with run in sold 102. A toe ramp 144 may be provided under the toe portion 110 of run insole 102. Toe ramp 144 may primarily be provided by the angle of the toe portion or toe region 110 of spring 120. This angle may be anywhere from 0° to 25° in preferred embodiments. In one preferred embodiment, ramp angle 146 is 10° for a running shoe. The angle can be varied in different applications to provide differing flexural stiffening of the spring plate as it is flexed. A lesser initial angle, thus, will be stiffer at any given angle of flex. An insole can tune a shoe to provide progressive stiffness levels earlier or later in the flex depending on the initial ramp angle. This ramp angle 146 allows a natural stride for the runner as the shoe rockers forward onto the toe of the user. As the big toe portion 130 of the toe ramp 144 further flexes the user is assisted by the flex loading of spring 120 and providing an energy return at as the user goes through the stride. The flex of toe ramp 144 is preferably progressive25315such that it substantially limits the total toe flex to a point at which the big toe of the user is fully engaged but not over flexed. The engagement of the big toe in dorsiflexion provides the final foot-engaged push at the end of a runner’s stride. Thus, toe ramp 144 provides an extra lengthening of the support in the footwear for higher speeds with a longer lever-arm of the foot being assisted by the progressive stiffness of toe ramp 144. Such an extra leverage at the end of the stride essentially provides a higher gear at toe exit for increased performance of the runner.
[0039] The cross-sectional view of Figure IK shows the spring plate 120 held close to the top of the insole 102. Keeping the spring plate 120 near the sole of the foot provides a low amount of differential movement between the foot and the plate and high energy return to the foot. It also decreases any loss at the foot joints and serves as a dynamic shank for the insole 102 and the shoe 100. In preferred embodiments, the distance between the bottom of the spring plate 120 and the top of the run insole 102 is between 4mm and 7mm. Thus, the plate increases the performance of the footwear overall and can be tailored to differing specific footwear applications. The spring plate 120 can also provide some of the overall support that the insole provides to the foot of the wearer.
[0040] Arch camber 148 is also show n in Figures 1 J and IK. Arch camber 148 also provides additional comfort and energy returned as the runner flexes through the mid portion of run insole 102. The camber may match the anatomical medial longitudinal arch of the foot. The stiffness and energy return of spring plate 120 can be modified by changing the thickness of the plate, changing the spring plate 120 materials, or changing the geometry of the plate such as cutouts in the plate or extra camber, for example. The plate thickness and / or materials may25315change over the length and / or width of the plate to reach desired characteristics. For example, a particular use might benefit from a stiffer toe portion than the arch portion.
[0041] The cushion 116 may be formed of a semi-rigid foam compression molded and formed with recess 138 to secure the spring plate 120 therein. Alternatively, the foam can be injection molded to shape. The spring plate 120 may be placed in the mold prior to foam injection or compression molding or may be post-applied with an adhesive or mechanical fixation. Ideally spring plate 120 moves with the foam material of cushion 116 as it flexes rather than the foam sliding relative to the spring plate. Thus, the preferred construction allows the plate to move dynamically in conjunction with the cushion layer and any other support layers.
[0042] Figures 2A and 2B show a slightly different embodiment of run insole 202. In this embodiment, the heel extension 134 is omitted. Also note in this embodiment the supercritical beaded thermoplastic polyurethane (TPU) material used for cushion 216. Various dimensions angles and geometries can change depending on the desired characteristics for insole 202. Thus, for example, a lesser or greater ramp angle 146 / 246 or arch camber 148 / 248 may be used.
[0043] Turning now to Figure 3A, a court shoe 300 with a court insole 302 is illustrated. Court shoe 300 includes a different outsole 304, midsole 306, and upper 308 than would be used with a running shoe. A court shoe needs to provide agility, stability, and performance for jumps and changes in direction, more so than a running shoe. Court insole 302 compliments the court shoe 300 to amplify performance and stability for the types of uses court shoes encounter, whether a basketball shoe, a tennis shoe, volleyball shoe, racquetball shoe,25315pickleball shoe, or any other shoe for use on a hard-court surface where direction changes are important.
[0044] In one preferred embodiment, court insole 302 includes a toe portion 310, an arch portion 312, and a heel portion 314. A cushion 316 extends from front to back with a spring 320 secured on the bottom of the cushion, or at least below the top surface of the cushion. This particular insole is somewhat different than the run insole in many ways. A truncated heel portion 322 is provided in which the spring plate 320 does not extend much or at all past the spring midfoot portion 324. Preferably, a supplemental heel cushion 350 is provided rearward of the spring midfoot portion 324. A more significant difference in this preferred court insole is a support member 352 that provides a more structural heel cup 354. Support member 352 extends from the heel where it forms a heel cup around the supplemental heel cushion 350 and forward to the arch portion 312 of the court insole 302. Thus, arch support portion 356 and lateral support portion 358 are provided on the medial and lateral sides of court in sole 302 as shown in Figures 3A and 3B.
[0045] Figure 3B also shows the detail of relief slots 360 in the lateral side of the metatarsal head portion 326 of spring plate 320. These relief slots form fingers 362 that extend outwardly and allow a bit more flex on the lateral side of insole 302. Such additional flex can be advantageous for some decoupling when landing from a jump. The fingers provide a slight bit of additional flex along the lateral side of the metatarsal midfoot portion 324 while still dynamically guiding the foot to a stable position on the court floor. The depth of the relief slots can vary but is preferably about 5 to 7mm width.
[0046] As can be ascertained from Figure 3B and Figures 3C through 3G, support member 352 overlaps with spring plate 320, at least along the spring midfoot portion 324. The25315support member 352 can extend forward on both sides of plate 320 even up to near the metatarsal head portion 326 of spring plate 320. As is illustrated in the exploded view of Figures 3C through 3G, support member 352 includes a support bridge 364 that extends betw een the medial and lateral sides of support member 352. This bridge also forms an opening 366 in the preferred embodiment positioned at the middle of the heel portion 314. Spring midfoot portion 324 interfaces, preferably, with the underside of support bridge 364. The underside of support bridge 364 preferably includes a slight recess therein relative to the medial and lateral sides of support member 352 into which the spring midfoot portion 324 can nest. As seen in Figure 3G supplemental heel cushion 350 nests within support opening 366. Alternatively, supplemental heel cushion 350 may simply be a downward projection of cushion 316 in the region of the support opening 366. In the preferred embodiment, supplemental heel cushion 350 is a different type of foam that provides good impact attenuation. A preferred material is a supercritical TPU matrix as discussed above in connection with the run insole 102.
[0047] Also adding court performance, printed silicone overlays 374 on the top of fabnc layer 318 at least in the metatarsal head portion 326 provide increased internal traction for more instant response in directional changes. In some preferred embodiments, the overlays run from the heel all along the lateral side of the insole and into the forefoot portion.
[0048] In preferred embodiments, the thickness of the court insole 302 from the bottom of the spring plate 320 to the top of the insole is between 4mm to 7mm.
[0049] Referring to Figure 3F, spring plate 320 preferably includes toe ramp at about 10 degrees. Some arch camber is also provided as the rearward end of the spring plate curves upwardly to engage with the bottom of support bridge 364 of support member 352. In preferred embodiments the rise of the arch region of the spring plate 320 is about 7mm. Thus,25315while the toe ramp angle may be similar to that of run insole 402, court insole 302 preferably does not include a big toe slot 132 as the engagement of the big toe for straight-line performance is not as important. The continuous toe portion in the court spring plate 320 provides more stability for aggressive direction changes.
[0050] A final embodiment of an insole specifically tailored to a certain type of footwear is shown in Figures 4A through 4 E. As seen in Figure 4A, a cleat shoe 400 is provided that includes an outsole 404 and an upper 408. In the example of cleated footwear, midsoles are minimized or omitted entirely. Thus, the foot of the user is secured close to the cleated outsole to maintain stability with a positive engagement with turf having the foot closer to the turf. The cleat insole 402 provides some cushioning within the cleat 400 but is also quite thin to maintain the foot close to the ground. The turf itself provides cushion such that damaging impacts are less likely than on a court, running path, or road. Also of note, the structure of the cleat upper 408 is such as to hold the heel and forefoot such as the metatarsal region tightly within the cleat shoe 400. Thus, the cleat insole 402 must conform to the inside of the cleat shoe 400.
[0051] One feature of a preferred embodiment of cleat insole 402 resides in the rearward end of cleat plate 420. The spring plate 420 is split into a forked heel, preferably starting at a reward portion of the spring midfoot portion 424. The forked heel 422 forms a medial arm 470 and a lateral arm 472 that diverge as they extend rearwardly such that they cup a center portion of the heel with a heel recess 436 at the rearward end thereof. Thus, the forked heel allows the sides of the heel portion of cleat insole 402 to conform better to the narrow interior of any particular cleat shoe 400 while still providing support and bending stiffness due to the longitudinally extending forks. Cleat shoes 400 already provide a heel cup. thus the25315forked heel 422 of the insole 402 can conform and complement cleat heel cup structure for increased performance. The forked heel structure accommodates different fits, narrow fits, and downsized fits that cleat wearers commonly prefer. The insole 402 with the spring plate 420 allows some independent response with the cleat outsole. The wearer can still feel the connection with the cleat architecture while gaining spring loading and flexing for energy return and forward propulsion. Additional comfort may also result by providing a bridging structure between outsole cleats. The heel recess 436 providing an opening between and rearw ard of the forks helps prevent the heel of the foot from sitting too high in the cleat and helps prevent heel slippage - nesting the middle of the heel rearward and betw een the rearward ends of the forks.
[0052] Conformance with a tight cleat shoe 400 is also provided by relief slots 460 that form medial fingers 468 and lateral fingers 462 on the medial and lateral sides of metatarsal head portion 426. Preferably, four slots of varying depth are provided to create three fingers on each side of metatarsal head portion 426. The fingers 462, 468 provide spring return and spread the load exerted by the foot while still allowing medial and lateral flex as the foot of the athlete pushes into the turf for direction changes. Additional or few er slots may be used to tune the performance to the activity7, footwear, and user.
[0053] No toe ramp (i.e., zero degree toe ramp) is provided in the preferred embodiment of the cleat insole 402. Some small arch camber can be provided. In alternate embodiments more slots or fewer slots and fingers can be provided. Likewise, the geometry and depth of the slots and fingers can be altered depending on perform and some variables desired.- 17 - LOW
[0054] As is shown in the exploded view of Figures 4C through 4E a thin cushion 416 is provided between a fabric layer 418 and spring plate 420. The whole assembly is kept to minimum thickness. As in the court insole 302, The cleat insole 402 may include some gripper material such as printed silicone overlays 474 on the top surface of fabric layer 418, especially in the metatarsal head region 426 (forefoot) and heel region of the cleat insole 402. As with the court insole 302, these traction overlays 474 improve direction change responsiveness.
[0055] In preferred embodiments, the thickness of the cleat insole 402 from the bottom of the spring plate 420 to the top of the insole is between 3.5mm and 5.0mm (most preferably 4.0mm). Thus, the cleat spring plate 420 may be slightly thicker than the court spring plate 320 or the run spring plate 120. A slightly thicker plate 420 (preferably between 1.25mm and 1.5mm) provides a stiffer insole 402. A compression molded construction method can be employed to keep the insole 402 thin. The spring plate 420 preferably has a slight arch camber but no toe ramp. This provides more stiffness gain in bending flex as the toe portion 428 of the spring plate 420 bends from flat with a constant or progressive spring rate.
[0056] As can be ascertained from the four embodiments described above, performance insoles can be created to provide advantages that are tailored to specific footwear and sport applications. Thus, spring plate thicknesses, geometries, flex characteristics, and curvatures for camber or toe ramp, can be provided to complement and improve upon the features of commercially available footwear for various specific sports or use cases. The differing features of each of the embodiments discussed above can be mixed or matched to achieve differing performance advantages, depending on the user and the use. The flex characteristics of the spring plate 120, 220. 320, 420 can be altered with thickness changes,25315material changes, and / or internal fiber direction changes. Any of these variables can be varied over the length and width of the spring plate.25315
Claims
The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:
1. An insole for insertion into footwear above a footwear midsole, the insole comprising:a toe portion, a metatarsal portion, a mid-portion, and a heel portion;a cushion extending from the toe portion of the insole to the heel portion of the insole, the cushion having a top surface and a bottom surface; anda spring plate secured below the top surface of the cushion, the spring plate extending from the toe portion of the insole to at least the mid-portion of the insole, the spring plate having at least one slot providing additional flex to portions of the spring plate adjacent the at least one slot.
2. The insole of claim 1, wherein the at least one slot is disposed in a toe portion of the spring plate, the slot separating the support provided by the plate under a big-toe region of a toe portion of the plate from a remainder of the toe portion of the plate.
3. The insole of claim 2, wherein the plate includes a rear end with a medial flange on the medial side of the insole in the heel portion of the insole, the medial flange being narrower than the remainder of the plate in the heel portion of the insole.
4. The insole of claim 2, wherein the plate includes a heel recess in a heel portion of the plate, the heel recess forming an inwardly curved shape in a lateral mid-portion of the heel portion of the plate.
5. The insole of claim 2, wherein the big-toe region of plate is angled upwardly relative to a portion of the plate in the metatarsal portion of the insole.
6. The insole of claim 5, wherein the angle of the big-toe region of the plate is between five and 15 degrees relative to the metatarsal portion of the plate.
7. The insole of claim 2, wherein the portion of the plate corresponding to the mid-portion of the insole includes positive camber along a portion of a longitudinal axis of the plate.
8. The insole of claim 1 , wherein the at least one slot includes a slot extending into a lateral side of the spring plate in a metatarsal portion of the plate.
9. The insole of claim 8, wherein a plurality of slots are provided on the lateral side of the spring plate, the slots creating at least one laterally extending finger.
10. The insole of claim 8, wherein a rearward end of the spring plate terminates in a midportion of the spring plate, forward of a heel portion of the insole.
11. The insole of claim 10, further comprising a cupping support member extending from the heel portion of the insole to the mid-portion of the insole, the cupping support member overlapping the rearward end of the spring plate.
12. The insole of claim 11 , wherein the cupping support member includes an opening under a mid-portion of the heel portion of the insole.
13. The insole of claim 12, wherein a supplemental pad is secured within the opening in the cupping support member.
14. The insole of claim 1, wherein the at least one slot includes a slot in a heel portion of the spring plate, the slot creating a forked heel portion of the spring plate with a rearwardly extending medial arm and a rearwardly extending lateral arm.
15. The insole of claim 14, wherein the spring plate includes slots extending into the lateral side of the spring plate in the metatarsal portion of the spring plate, the slots creating at least one laterally extending finger.
16. The insole of claim 14, wherein the spring plate includes slots extending into the medial side of the spring plate in the metatarsal portion of the spring plate, the slots creating at least one medially extending finger.
17. The insole of claim 14, wherein the slot in the heel portion of the spring plate extends at least to the mid-portion of the insole.2531518. An insole for placement in footwear above the midsole of the footw ear, the insole comprising:a toe region, a metatarsal region, a mid-region, and a heel region;a cushion layer extending from the toe region of the insole to the heel region of the insole, the cushion layer having a top surface and a bottom surface; and a spring plate secured below the top surface of the cushion layer, the spring plate having a generally longitudinally extending slot in the toe region, the slot separating at least a portion of a big-toe region of the spring plate from the remainder of the toe region of the spring plate.
19. The insole of claim 18, wherein the spring plate further comprises a medial finger extending rearwardly from a wider portion of the spring plate in the heel region of the spring plate.
20. The insole of claim 18, wherein the spring plate includes positive camber in a midregion of the spring plate.
21. The insole of claim 18, wherein the big-toe region of the spring plate includes an upward ramp angle from a rearward portion of the big-toe region to a forward end of the bigtoe region.
22. The insole of claim 21, wherein the remainder of the toe region of the spring plate includes an upward ramp angle.
23. An insole for placement in footwear above a midsole of the footwear, the insole comprising:a toe region, a metatarsal region, an arch region, and a heel region;a cushion layer extending from the toe region to the heel region of the insole, the cushion layer having a top surface and a bottom surface;a spring plate secured below the top surface of the cushion layer, the spring layer extending from the toe region through the arch region of the insole; and25315a cupping support member extending longitudinally across the heel region and the arch region of the insole, the cupping support member overlapping with a rearward end of the spring plate.
24. The insole of claim 23, wherein the spring plate further includes a plurality of slots extending into the lateral side of the spring plate in the metatarsal region of the spring plate, the plurality of slots forming at least one laterally extending finger.
25. The insole of claim 23, wherein the cupping support member includes a recess to receive the rearward end of the spring plate forward of the heel region.
26. An insole for placement in a footwear above a midsole of the footwear, the insole comprising:a toe region, a metatarsal region, an arch region, and a heel region;a cushion layer extending from the toe region to the heel region of the insole, the cushion layer having a top surface and a bottom surface; anda spring plate secured below the top surface of the cushion layer, the spring layer extending from the toe region to the heel region of the insole, wherein a rearward portion of the spring plate at least in the heel region includes a split forming a medial arm and a lateral arm.
27. The insole of claim 26, wherein the spring plate includes a plurality of medial slots extending generally laterally into the medial side of the spring plate in the metatarsal region of the spring plate, the plurality of slots forming at least one finger.
28. The insole of claim 26, wherein the spring plate includes a plurality of lateral slots extending generally laterally into the lateral side of the spring plate in the metatarsal region of the spring plate, the plurality' of slots forming at least one finger.25315