Article of footwear having ground surface material accumulation prevention structure

An article of footwear includes a sole having a lower surface, and a reactive element disposed on the lower surface of the sole. The reactive element has an exposed surface, and the reactive element is configured to transition the exposed surface between a first state and a second state in response to a compression force applied to the reactive element by an external ground surface in a user activity, to prevent accumulation of ground surface material, such as mud, dirt, clay, sand, slush, etc., compacting on the sole of the article of footwear in the user activity. The reactive element may include an elastomeric dome shaped popper that compresses flat in response to a compression force and then pops back to a non-compressed state in response to release of the compression force.

FIELD

The present invention relates generally to an article of footwear and, more particularly, to a sports shoe with cleats.

BACKGROUND

An article of footwear may be used on many alternative types of ground surfaces. An article of footwear having at least one ground surface traction element may be used to provide better traction on certain types of ground surface. In each case, use of an article of footwear in some types of ground surfaces, e.g., mud or slush, may result in accumulation of compacted ground surface material on the lower surface of the article of footwear. Accumulation of ground surface material on the lower surface of an article of footwear may reduce traction of the article of footwear and/or adversely affect performance characteristics of the article of footwear and the user.

DETAILED DESCRIPTION

In one aspect, an article of footwear may comprise a sole and a reactive element. The sole may have a lower surface. The reactive element may be disposed on the lower surface of the sole. The reactive element may have an exposed surface, and the reactive element may be configured to transition the exposed surface between a first state and a second state in response to a compression force applied to the reactive element by an external ground surface in a user activity, to prevent accumulation of ground surface material compacting on the sole of the article of footwear in the user activity.

In some embodiments, the reactive element may further comprise webbing configured to secure the reactive element on the lower surface of the sole.

In some embodiments, the reactive element may be integrally formed with the lower surface of the sole by bonding or molding.

In some embodiments, the sole may further comprise at least one ground surface traction element disposed on the lower surface of the sole, and the reactive element may be secured to the lower surface of the sole by the at least one ground surface traction element.

In some embodiments, the at least one ground surface traction element may include at least one cleat that is removably secured to the lower surface of the sole, and the reactive element may be secured to the lower surface of the sole by the at least one cleat.

In some embodiments, the reactive element may be secured to the lower surface of the sole by securing the at least one cleat to the lower surface of the sole with the webbing disposed between the at least one cleat and the lower surface of the sole.

In some embodiments, a configuration of the reactive element may conform to a configuration of plural ground surface traction elements disposed on the lower surface of the sole.

In some embodiments, the article of footwear may further include a webbing configured to secure the reactive element to the lower surface of the sole of the article of footwear. In such embodiments, the webbing and the resilient member may be formed by a unitary resilient material.

In some embodiments, the reactive element may comprise an elastomeric polymer dome, and the elastomeric polymer dome may be optionally made of a thermoplastic or thermosetting material.

In some embodiments, the elastomeric polymer dome may have a symmetric shape or an elongated shape.

In some embodiments, the webbing may include a tab associated with a ground surface traction element on the lower surface of the sole to secure the resilient member to the lower surface of the sole of the article of footwear.

In some embodiments, the tab of the webbing may include a through-hole configured to engage a portion of the ground surface traction element.

In some embodiments, the ground surface traction element may be a cleat, and the portion of the cleat may be a screw-in base portion that passes through the through-hole to capture the tab of the webbing between the cleat and the lower surface of the sole.

In some embodiments, in the first state, the exposed surface portion may be in a compressed state proximal the lower surface of the sole. In some embodiments, in the second state, the exposed surface portion may be in a decompressed state distal of the lower surface of the sole relative to the first state.

In some embodiments, the reactive element may be configured to transition the exposed surface to the first state in response to a compression force applied between the sole of the article of footwear and the external ground surface and to the second state in response to release of the compression force.

In some embodiments, the reactive element may include a resilient member having a spring constant k.

In one aspect, a method of making an article of footwear may include a step of providing a sole having a lower surface. The method may further include a step of placing a reactive element on the lower surface of the sole. The reactive element may have an exposed surface, and the reactive element may be configured to transition the exposed surface between a first state and a second state in response to a compression force applied to the reactive element by an external ground surface in a user activity, to prevent accumulation of ground surface material compacting on the sole of the article of footwear in the user activity.

In some embodiments, the method may include providing a molding system. The molding system may include a first mold plate including a first mold cavity and a second mold plate including a second mold cavity. The method may include a step of placing a first piece of mold material in between the first mold plate and the second mold plate in a position adjacent to the first mold cavity. The method may include a step of placing a second piece of mold material in between the first mold plate and the second mold plate in a position adjacent to the second mold cavity. The method may include a step of pressing the first mold plate and the second mold plate together. The method may include a step of suctioning air from first mold cavity such that the first piece of mold material is drawn into the first mold cavity. The method may include a step of suctioning air from second mold cavity such that the second piece of mold material is drawn into the second mold cavity. The method may include a step of applying heat to both the first mold plate and the second mold plate to mold the first piece of mold material and the second piece of mold material into a resilient element having a dome shaped portion formed by the first piece of mold material, a flat portion formed by the second piece of mold material, and a webbing formed by both the first piece of mold material and the second piece of mold material, the webbing having at least one tab. The method may include a step of attaching the resilient element to the lower surface of the sole such that the flat portion of the resilient element lies against the lower surface of the sole.

In some embodiments, the step of attaching the resilient element to the lower surface of the sole may include placing a shaft of a cleat through a hole on the tab of the webbing of the resilient element and attaching the shaft of the cleat to the lower surface of the sole.

In some embodiments, the step of attaching the resilient element to the lower surface of the sole includes molding the resilient element to the lower surface of the sole.

Other systems, methods, features and advantages of the invention will be, or will become, apparent to one of ordinary skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description and this summary, and within the scope of the invention, and be protected by the following claims.

FIGS. 1-3illustrate an embodiment of an article of footwear including ground surface material accumulation prevention structure according to the present invention.FIG. 1is a perspective view of an embodiment of an article of footwear10including ground surface material accumulation prevention structure12according to the present invention.FIG. 2is a plan view of a lower surface of a sole, or sole plate, of the article of footwear ofFIG. 1.FIG. 3is a side profile view of the article of footwear ofFIG. 1.FIGS. 1-3illustrate an embodiment of a configuration of the article of footwear10and ground surface material accumulation prevention structure12. Those skilled in the art readily will appreciate alternative embodiments in view of the present disclosure.

Generally, the term “sole,” “sole plate,” or “cleated sole plate” as used in this detailed description and throughout the claims includes an element configured to be disposed as an outsole for an article of footwear that includes one or more ground surface traction element. A sole may take the form of an outsole or a sole structure for any article of footwear including, but not limited to: soccer shoes, baseball shoes, hiking boots, football shoes, sneakers, rugby shoes, basketball shoes, track shoes, snow shoes, as well as other kinds of shoes. In an exemplary embodiment, a sole may comprise essentially an entirety of an outsole of an article of footwear. In other embodiments, a sole may comprise a portion of an outsole of an article of footwear, including, but not limited to one or more of a forefoot region, a midfoot region, and/or a heel region. In other embodiments, different configurations of a sole may be included in an article of footwear. For purposes of illustration, in various embodiments herein a sole is shown in isolation. In other embodiments, however, the sole could be associated with an upper for an article of footwear.

As shown inFIGS. 1-3, in some embodiments article of footwear10may include an upper14and a sole or sole plate16. Upper14may be any known or later developed upper structure or design. Those skilled in the art readily will be able to select a structure and design for the upper14suitable for a desired type of article of footwear10and intended use.

Sole or sole plate16may be any known or later developed sole structure and design suitable for a desired article of footwear10having ground surface material accumulation prevention structure12of the present invention. Sole16may include one or more layers, including inner and/or midsole structures (not shown), made of known or later developed material(s) suitable for a desired use or activity. Sole plate16may include ground surface traction elements17suitable for an intended use or activity of the article of footwear10. In some embodiments the ground surface traction elements17may include fixed or removable cleats or studs. In some embodiments a ground surface traction element17may locate, support, and/or secure ground surface material accumulation prevention structure12relative to the sole16of the article of footwear10. Those skilled in the art readily will be able to select a structure, design, material(s), and construction for the sole16, including a number and configuration of ground surface traction elements17, suitable for a desired type of article of footwear10and intended use.

Article of footwear10may include a forefoot region18(distal end), a heel region20(proximal end) opposite forefoot region18, and a midfoot region22disposed between forefoot region18and heel region20. Forefoot region18may include a toe region24(most distal end) and a balls of foot region26disposed adjacent the toe region24. Forefoot region18may include a flex region28located between the toe region24and the balls of foot region26that facilitates flexion of the user's toes relative to the foot in active use of the article of footwear10. As shown inFIGS. 1-3, in some embodiments the flex region28may include a sipe30formed in a lower surface32of the article of footwear10, extending in a medial/lateral direction, to facilitate flexion. Midfoot region22may be located between the forefoot region18and the heel region20, and may include a shank and/or arch region of the article of footwear10. As used herein, the terms forefoot region18, heel region20, midfoot region22, toe region24, balls of foot region26, and flex region28refer to general areas or regions and not to particularly defined structures or boundaries. Those skilled in the art readily will appreciate alternative versions of structures, areas, and regions described herein in view of the context discussed herein.

Article of footwear10may include a medial portion34and a lateral portion36opposite medial portion34. Medial portion34may include a medial side of the article of footwear10, including a medial edge38. Lateral portion36may include a lateral side of the article of footwear10, including a lateral edge40.

Ground surface material accumulation prevention structure12may be disposed on a lower surface32of sole16. Ground surface material accumulation prevention structure12may include a reactive element42having an exposed surface. In some embodiments, reactive element42optionally may have an exposed friction wear surface43. In some embodiments, ground surface material accumulation prevention structure12may include webbing44for locating, supporting, and/or securing the reactive element42on the lower surface32of sole16. In some embodiments, webbing44may include one or more tabs46. In some embodiments, a tab46may be associated with a ground surface traction element17to locate, support, and/or secure ground surface material accumulation prevention structure12to the lower surface32of sole16relative to the ground surface traction element17. Those skilled in the art readily will be able to select a design and configuration of ground surface material accumulation prevention structure12, including webbing44, suitable for a desired configuration of an article of footwear10and its intended use.

FIG. 4is an exploded perspective view of an embodiment of the article of footwear10ofFIGS. 1-3, illustrating an embodiment of ground surface material accumulation prevention structure12for the article of footwear. As shown inFIG. 4, in some embodiments sole16of the article of footwear10may include plural removable cleats or studs50(ground surface traction elements17). Each removable cleat50may include a head52configured to contact an external ground surface and a connector54configured to removably secure the cleat50to the lower surface32of sole16. Each head52may have a configuration (size, shape, depth, width, length, orientation, etc.) selected for a desired application and intended use of the article of footwear12. Exemplary shapes for ground surface traction elements17, including removable cleats50include, but are not limited to, rectangular, hexagonal, cylindrical, conical, circular, square, trapezoidal, diamond, ovoid, as well as other regular or irregular and geometric or non-geometric shapes. Those skilled in the art readily will be able to select a shape and/or configuration of each ground surface traction element17or cleat50, including a configuration of a cluster of plural ground surface traction elements17, based on a desired application or use of the article of footwear10. As shown inFIG. 4, in some embodiments each connector54may be threaded and configured to screw into a female threaded connector56in the lower surface32of sole16. Those skilled in the art readily will appreciate alternative connector structures and configurations for removably securing cleat50to the lower surface32of sole16of the article of footwear10.

As shown inFIG. 4, in some embodiments article of footwear10may include three ground surface material accumulation prevention structures12. One structure may be disposed in the toe area24. One structure may be disposed in the ball of foot area26of the forefoot area18. One structure may be disposed in the heel area20. The number and location of ground surface material accumulation prevention structures12is exemplary only. As discussed herein, a localized and overall configuration may provide a desired localized and overall ground surface material accumulation prevention function for the article of footwear10.

As shown inFIG. 4, in some embodiments a ground surface material accumulation prevention structure12may be located within a cluster of ground surface traction elements17. In the embodiment ofFIG. 4, each ground surface material accumulation prevention structure12may include webbing44having at least one tab46. A tab46may be associated with a respective ground surface traction element17. A tab46may include structure configured for engaging a ground surface traction element17of the article of footwear10. For example, as shown inFIG. 4, in some embodiments each tab46may include a through-hole48sized and configured to receive a male connector54of a removable cleat50to secure the tab46and ground surface material accumulation prevention structure12to the lower surface32of sole16of the article of footwear10.

As shown inFIGS. 1-4, in some embodiments a cluster may include four ground surface traction elements17. However, it will be appreciated that a cluster may include a different number of ground surface traction elements17, and that a ground surface traction element17may be included in more than one cluster. The number and configuration of ground surface traction elements17may vary based on a number of factors, including a size and intended use of the article of footwear10and a size, material, and configuration of ground surface traction elements17. Those skilled in the art readily will be able to select a number and configuration of ground surface traction elements17suitable for a desired article of footwear10and intended use.

FIG. 5is a cross-sectional view of an embodiment of a ground surface material accumulation prevention structure12ofFIG. 4taken along section line5-5ofFIG. 2. As shown inFIG. 5, in some embodiments ground surface material accumulation prevention structure12may be removably secured to a lower surface32of sole16by removable studs50. Each stud50may include a threaded male connector54that may be inserted through a through-hole48of a tab46of webbing44of the ground surface material accumulation prevention structure12, where threaded male connector54may be screwed into a female threaded connector56embedded in sole16to removably secure the ground surface material accumulation prevention structure12to the lower surface32of sole16. In this manner, ground surface material accumulation prevention structure12may be securely supported against the lower surface32of sole16. This configuration may prevent ground surface material from entering and accumulating in a gap at an interface between the ground surface material accumulation prevention structure12and the lower surface32of sole16. As shown inFIG. 5, in some embodiments article of footwear10may include a rigid sole plate16and a relatively soft inner sole or liner layer501, with at least a portion of ground surface material accumulation prevention structure12disposed below rigid sole plate16.

FIG. 6is a side profile view illustrating an embodiment of a reactive element42of ground surface material accumulation prevention structure12, andFIG. 7is a perspective view of the reactive element42ofFIG. 6. As shown inFIGS. 6 and 7, in some embodiments, reactive element42may be dome shaped. As shown inFIGS. 6 and 7, in some embodiments, reactive element42optionally may include a friction wear treatment surface43. Friction wear treatment surface43may be disposed in a location and configured to contact an external ground surface in active use of the article of footwear10. As shown inFIGS. 6 and 7, in some embodiments, friction wear treatment surface43may be located on a crest of a dome-shaped reactive element42.

Reactive element42may be configured to react in response to an externally applied compression force in active use of the article of footwear10. Reactive element42may be configured to collapse in response to a compression force applied to an exposed surface of the reactive element42by an external ground surface, to absorb and store a portion of energy from the applied compression force, and to generate therein a reactive force that biases the reactive element42to return to a non-collapsed state upon release of the applied compression force. In some embodiments reaction element42may be configured to immediately and/or continuously return to a non-compressed state in response to release of a compression force. In some embodiments, the reactive element42may be configured to ‘pop’ back from a compressed state to a non-compressed state in response to release of an external compression force.

Reactive element42may have any geometric shape that provides a desired reactive functional characteristic. As shown inFIGS. 6 and 7, in some embodiments, reactive element42may have a hollow semi-spherical dome shape. This configuration may provide a reactive functional characteristic that is substantially consistent regardless of a direction in which an external compression force is applied to the reactive element, e.g., based on an orientation of the article of footwear10upon impact with a ground surface. In some embodiments, reactive element42may have a multi-faceted dome shape. In some embodiments, reactive element42may have a symmetrical or non-symmetrical shape.

Reactive element42may have a base plan shape or footprint selected for a particular article of footwear configuration or application. In some embodiments, reactive element42may have a base plan shape or footprint configured for location in a particular area of the article of footwear10. As shown inFIGS. 1-4, in some embodiments reactive element42may be sized and shaped for location between a duster of ground surface traction elements17in a selected one of the toe region24or balls of foot region26of the forefoot region20, or in the heel region20.

Reactive element42may be configured to provide a reactive force/functional characteristic in a selected direction. Reactive element42may be configured to provide a reactive force/functional characteristic in a direction associated with a location of the ground surface material accumulation prevention structure12on the article of footwear10. For example, reactive element42may be located in the toe region24and configured to generate a reactive force/functional characteristic that acts in a proximal direction relative to the heel region20.

FIG. 8is a cross-sectional view of a second embodiment of a ground surface material accumulation prevention structure12ofFIG. 4taken along section line5-5ofFIG. 2. Similar toFIG. 5, as shown inFIG. 8, in some embodiments ground surface material accumulation prevention structure12may be removably secured to a lower surface32of sole16, e.g., by removable studs50. As shown inFIG. 8, in some embodiments reactive element42may have an elongated dome shape, e.g., that has an axis that extends in a direction between opposing ground surface traction elements17(e.g., studs50). This configuration may provide a ground surface material accumulation prevention structure having a size and shape that conforms to a desired location on the article of footwear (e.g., in the heel region20), and/or conforms with a location and configuration of sole16, including a configuration of ground surface traction elements17.

As shown inFIGS. 8-10, in some embodiments ground surface material accumulation prevention structure12may have a multi-piece construction. As shown inFIG. 8, in some embodiments ground surface material accumulation prevention structure12may include a base portion formed by webbing44and a separate reactive element42. In some embodiments reactive element42may be separately pre-molded and then fixed to webbing44. For example, in some embodiments reactive element42may be fixed to webbing44by a bonding or molding process. In some embodiments, reactive element42may be removably secured to webbing44. As shown inFIG. 8, in some embodiments base webbing44may include a generally annular flange45, and reactive element42may have a hollow dome shape including an annular flange47that mates with flange45of base webbing44. As shown inFIGS. 8 and 10, in some embodiments annular flange45of base webbing44may face radially outward, and annular flange47may be formed on an inner facing surface of hollow dome-shaped reactive element42. Alternatively, in some embodiments annular flange45of base webbing44may face radially inward, and annular flange47may be formed on an outer perimeter surface of the hollow dome-shaped reactive element42. In each case, reactive element42and base webbing44may be made of different materials, e.g., made from different mold materials by respective pre-molding processes. In some embodiments, base webbing44may be integrally formed with sole16of the article of footwear10, e.g., by a bonding or molding process. In the case of a removable reactive element42, this configuration may enable a user to apply, remove, or replace, a ground surface material accumulation prevention structure12during active use of the article of footwear10, e.g., during a soccer game.

FIG. 11is a cross-sectional view of a third embodiment of a ground surface material accumulation prevention structure12ofFIGS. 1-3taken along section line5-5ofFIG. 2. Similar to the embodiments above, as shown inFIG. 11, in some embodiments ground surface material accumulation prevention structure12may be removably secured to ground surface traction elements17on the lower surface32of sole16of the article of footwear10. As shown inFIG. 11, however, in some embodiments ground surface traction elements17may be integrally molded with sole16and a tab46may be provided with a through-hole48that may be stretched over a ground surface traction element17to capture and engage a base portion58of the ground surface traction element17. Base portion58of the ground surface traction element17may be formed with an undercut or angled surface that biases an edge of the through-hole48of the tab46to securely remain at the base portion58. In this manner, base webbing44may be securely supported against the lower surface32of sole16. This configuration may facilitate preventing ground surface material from penetrating into a gap at an interface between the base webbing44and sole16.

FIG. 12is a cross-sectional view of a fourth embodiment of a ground surface material accumulation prevention structure12ofFIGS. 1-3taken along section line5-5ofFIG. 2. As shown inFIG. 12, in some embodiments ground surface material accumulation prevention structure12may be integrally formed with sole16of an article of footwear10. In some embodiments, reactive element42may be integrally formed on the lower surface32of sole16. In some embodiments, reactive element42may be integrally formed on the lower surface32of sole16by a bonding or molding process. In some embodiments, webbing44of the ground surface material accumulation prevention structure12may be integrally formed with a lower surface32of sole16. In some embodiments, webbing44may be integrally formed with a ground surface traction element17, e.g., by bonding or molding process. Those skilled in the art readily will appreciate alternative configurations and bonding or molding processes suitable for forming a sole16for an article of footwear10having an integral ground surface material accumulation prevention structure12. Those skilled in the art readily will appreciate that an article of footwear10having integrally molded ground surface material accumulation prevention structure12may have utility in particular applications requiring a permanent non-clogging function.

Each of the above embodiments illustrates a feature having an alternative configuration that may have an advantage over one or more alternative embodiment(s)/configuration(s) in a particular application.

Molding System for Molding Independent Ground Surface Material Accumulation Prevention Structure

FIGS. 13-15illustrate an embodiment of a molding system1300for molding ground surface material accumulation prevention structure12of the present invention.FIG. 13schematically illustrates an embodiment of molding system1300in an exploded, open mold configuration.FIG. 14schematically illustrates molding system1300in a closed mold configuration optionally including a vacuum system. AndFIG. 15is a sectional view of molding system1300taken along section line15-15ofFIG. 14, illustrating in cross-section a molded ground surface material accumulation prevention structure12.

In some embodiments a molding system may mold individual, independent ground surface material accumulation prevention structures suitable for use with an article of footwear having plural ground surface traction elements arrange in a duster. In some embodiments, one or more ground surface traction elements may be removably attached to the lower surface of the sole of the article of footwear. As shown inFIGS. 13-15, in some embodiments molding system1300may be used to mold ground surface material accumulation prevention structure12suitable for use with an article of footwear10having plural removable cleats or studs50(see, e.g.,FIGS. 4-7).

As shown inFIGS. 13-15, in some embodiments molding system1300may include a lower mold plate1310, an upper mold plate1312, and an optional vacuum system1314. In some embodiments, molding system1300may include one or more components typically associated with a compression or thermal molding system, including components not described herein.

Lower mold plate1310may include at least one lower mold cavity for molding ground surface material accumulation prevention structure. As shown inFIGS. 13-15, in some embodiments lower mold plate1310may include first lower mold cavity1316and second lower mold cavity1318for molding respective first and second ground surface material accumulation prevention structures12. In some embodiments lower mold cavity1316may include a central dome-shaped recess portion1320and a lower webbing recess portion1322that may include at least one lower tab recess portion1324. As shown inFIGS. 13-15, in some embodiments, lower webbing cavity portion1322may include four lower tab recess portions1324. In some embodiments, each lower tab recess portion1324may include a raised lower central portion1326configured to form a through-hole in a tab46of a molded ground surface material accumulation prevention structure12.

Lower mold plate1310optionally may include vacuum system elements for facilitating a molding process. As shown inFIGS. 13-15, in some embodiments central dome-shaped recess portion1320may include one or more dome vacuum ports1328. In some embodiments, dome vacuum ports1328may be arranged in a pattern on a mold surface of the central dome-shaped recess portion1320suitable for drawing a first (lower) sheet of mold material1330into the central dome-shaped recess portion1320and onto a contour of the mold surface of the central dome-shaped recess portion1320in a molding process. In some embodiments, lower webbing recess portion1322may include lower webbing recess vacuum ports1332configured to draw the first (lower) sheet of mold material1330to a mold surface of the lower webbing recess portion1322, e.g., to a mold surface of lower tab recess portion1324, in a molding process. As shown inFIGS. 13-15, in some embodiments lower mold plate1310may include a lower vacuum manifold structure1333connecting the dome vacuum ports1328and lower webbing recess ports1332to a central vacuum source of vacuum system1314.

Upper mold plate1312may include at least one upper mold cavity for molding a ground surface material accumulation prevention structure. As shown inFIGS. 13-15, in some embodiments upper mold plate1312may include a first upper mold cavity1334corresponding to first lower mold cavity1316and a second upper mold cavity1336corresponding to lower mold cavity1318. In some embodiments first upper mold cavity1334may include a central base recess portion1338and an upper webbing recess portion1340that may include at least one upper tab recess portion1342. As shown inFIGS. 13-15, in some embodiments upper webbing recess portion1340may include four upper tab recess portions1342corresponding to the four lower tab recess portions1324.

Upper mold plate1312optionally may include vacuum system elements for facilitating a molding process. As shown inFIGS. 13-15, in some embodiments central base recess portion1338may include one or more central base vacuum ports1344configured to hold a second (upper) sheet of mold material1348to a mold surface of the central base recess portion1338in a molding process. In some embodiments upper webbing recess portion1340may include upper webbing recess vacuum ports1350configured to draw second (upper) sheet of mold material1348to a mold surface of upper webbing recess portion1342, e.g., to a mold surface of upper tab recess portion1342. As shown inFIGS. 13-15, in some embodiments upper mold plate1312may include an upper vacuum manifold structure1352connecting the central base recess portion vacuum ports1344and upper webbing recess ports1346to a central vacuum source of vacuum system1314.

In a molding process ofFIGS. 13-15, first (lower) sheet of molding material1330and second (upper) sheet of molding material1348may be disposed between the lower mold plate1310and the upper mold plate1312in registration with the at least one lower mold cavity (1316,1318) and at least one upper mold cavity (1334,1336). As shown inFIG. 13, the first (lower) sheet of mold material may be a single sheet or plural sheets, e.g., corresponding in number to the number of mold cavities in the molding system1300. For example, in the molding system ofFIGS. 13-15the number of first (lower) sheets of mold material1330may be two. Similarly, the second (upper) sheet of mold material may be a single sheet or plural sheets, e.g., corresponding in number to the number of mold cavities in the molding system1300. For example, in the molding system ofFIGS. 13-15the number of second (upper) sheets of mold material1348may be two.

The molding process optionally may include a layer of wear resistant surface material. As shown inFIG. 13, in some embodiments an optional wear resistant surface treatment material1356may be disposed between the first (lower) sheet of molding material1330and the lower mold plate1310so that the wear resistant surface treatment material1356is in registration with a central area of the central dome recess portion1320. In this manner, a molded reactive element42may be formed with a friction wear resistance surface43configured to contact an external ground surface.

The molding process may include a heat treatment and/or pressure treatment process, optionally with vacuum. In some embodiments, in the molding process the first (lower) sheet of mold material1330may be drawn by vacuum into the lower mold cavity (1316,1318) and take a shape and configuration conforming to the shape and configuration of a mold surface of the lower mold cavity (1316,1318); the second (upper) sheet of mold material1348may be drawn by vacuum into the upper mold cavity (1334,1336) and take a shape and configuration conforming to the shape and configuration of a mold surface of the upper mold cavity (1334,1336). In some embodiments, optional wear surface treatment material1356may be drawn into the lower mold cavity in registration with a central area of the central dome recess portion1320. In some embodiments, in a molding process first (lower) sheet of mold material1330, second (upper) sheet of mold material1348, and optional wear surface treatment material1356may be molded together to form a molded ground material accumulation prevention structure12having an integral/unitary structure. The method of making an article of footwear, including a molding process, is discussed in more detail below.

FIG. 15is a cross-sectional view taken along section lines15-15ofFIG. 14illustrating in cross-section a molded ground surface material accumulation prevention structure12product of molding system1300, in situ. The molding system may be opened to remove the molded ground material accumulation prevention structure12product. In some embodiments, any extra mold material formed on the molded product may be removed (e.g., cut) from the molded product prior to securing the ground surface material accumulation prevention structure12to an article of footwear, e.g., using removable cleats50(see, e.g.,FIGS. 1-4).

Mold materials for a molding process in the molding system ofFIGS. 13-15may be any known or later developed molding materials suitable for a desired ground material accumulation prevention structure. In some embodiments, the molding material may be a plastic material. In different embodiments, however, various types of molding material may be used to form a ground surface material accumulation prevention structure using molding system1300. In some embodiments, the molding material may include, but is not limited to, any one or more of the following materials: natural or synthetic rubber, hard foam, plastics, polymers, nylon, polyurethane, thermoplastic polyurethane (TPU), as well as any other deformable or rigid materials. However, it will be understood that any other materials could be used as the molding material. In addition, in some embodiments a ground surface material accumulation prevention structure may be produced using more than one molding material.

As shown inFIGS. 13-15, in some embodiments the mold material may be in the form of a sheet of mold material. In some embodiments first (lower) sheet of mold material1330, second (upper) sheet of mold material1348, and optional wear resistant surface treatment material1356may be different mold materials. In some embodiments, the mold material may be pre-formed or pre-cut to form a mold material blank. In some embodiments, a mold material blank may be sized and configured to correspond to a mold cavity (1316,1318) of the molding system. Those skilled in the art readily will be able to select various combinations of mold materials suitable for a particular application.

Molding System for Molding Integral Sole Plate and Ground Surface Material Accumulation Prevention Structure

FIGS. 16-18illustrate an embodiment of a molding system for molding a sole plate for an article of footwear, where the sole plate includes an integral ground surface material accumulation prevention structure.FIG. 16schematically illustrates an embodiment of molding system1600in an exploded, open mold configuration.FIG. 17schematically illustrates an embodiment of molding system1600in a closed mold configuration, optionally including a vacuum system. AndFIG. 18is a schematic cross-sectional view of molding system1600taken along section line18-18ofFIG. 17, illustrating in cross-section an embodiment of a molded sole plate including integral molded ground surface material accumulation prevention structure12, in situ.

As shown inFIGS. 16-18, in some embodiments molding system1600may include a lower mold plate1610, an upper mold plate1612, and an optional vacuum system1614. In some embodiments, molding system1600may include one or more components typically associated with a compression or thermal molding system, including components not described herein.

Lower mold plate1610may include a lower sole plate recess1615sized and configured to receive a lower surface of a sole or sole plate16for an article of footwear10and to mold ground surface material accumulation prevention structure12integral with sole plate16. In some embodiments, lower mold plate1610(and corresponding upper mold plate1612) may include provisions for making a matched pair of sole plates16.

Lower mold plate1610may include one or more lower mold cavities formed in the lower sole plate recess1615and configured to mold integral ground surface material accumulation prevention structure12. As shown inFIGS. 16-18, in some embodiments lower mold plate1610may include a first lower mold cavity1616and second lower mold cavity1620configured to mold respective ground surface material accumulation prevention structures12. In the embodiment ofFIG. 16, first lower mold cavity1616may be located in a forefoot region18of the lower mold plate recess1615and second lower mold cavity1618may be located in a heel region20of the lower mold plate recess1615. As shown inFIGS. 16-18, in some embodiments first mold cavity1616may be located in registration with a first cluster of ground surface traction elements17in the forefoot region18, and second mold cavity1618may be located in registration with a second cluster of ground surface traction elements located in the heel region20. First lower mold cavity1616may include a central dome recess portion1620and a webbing recess portion1622that may include at least one tab recess portion1624. As shown inFIGS. 16-18, in some embodiments webbing recess portion1622may include four tab recess portions1624. Each tab recess portion1624may include a cleat recess portion1626configured to receive a ground surface traction element17of sole plate16.

Lower mold plate1610may include optional vacuum system elements for facilitating a molding process. In some embodiments central dome recess portion1620may include one or more dome vacuum ports1628. Dome vacuum ports1628may be arranged in a pattern on a mold surface of the central dome recess portion1620configured to draw a sheet of mold material1630into the central dome recess portion1620and onto a contour of the mold surface of the central dome recess portion1620. In some embodiments webbing recess portion1622may include webbing recess vacuum ports1632configured to draw a sheet of mold material1630to a mold surface of the webbing recess portion1622, e.g., to a mold surface of tab recess portion1624. Lower mold plate1610may include a vacuum manifold structure1633connecting the dome vacuum ports1628and optional webbing recess ports1632to vacuum system1614.

Upper mold plate1612may include an upper sole plate recess portion1634sized and configured to receive an upper surface of sole plate16of the article of footwear10.

As shown inFIGS. 17 and 18, in some embodiments upper mold plate1612may include optional vacuum system elements for facilitating a molding process. In some embodiments the vacuum system may draw the sole plate16into upper sole plate recess portion1634of upper mold plate1612.

In a molding process ofFIGS. 16-18, a sole plate16and a sheet of mold material1630may be disposed between lower mold plate1610and upper mold plate1620in registration with the lower sole plate recess1615, the upper sole plate recess1634, and the first and second mold cavities (1616,1618). As shown inFIG. 16, in some embodiments the sheet of mold material may be a single sheet or plural sheets corresponding in number to the number of mold cavities in the molding system1600. For example, as shown inFIG. 16, in some embodiments the number of sheets of mold material1630may be two. In some embodiments an optional wear resistant surface treatment material1636may be disposed between the sheet of molding material1630and the lower mold plate1610so that the wear resistant surface treatment material1636is located in registration with a central area of the central dome recess portion1620.

The molding process may include a heat treatment and/or pressure treatment process, optionally with vacuum. In a molding process a sheet of mold material1630may be drawn by vacuum into the lower mold cavity (1616,1618) and take a shape and configuration conforming to the shape and configuration of a mold surface of the lower mold cavity (1616,1618). The sole plate16, the sheet of mold material1630, and the optional wear surface treatment material1636may be molded together to form a molded sole plate16and ground surface material accumulation prevention structure12having an integral/unitary structure. A method of making an article of footwear, including a molding process, is discussed in more detail below.

FIG. 18is a schematic sectional view illustrating in cross-section an embodiment of a molded sole plate with integral ground surface material accumulation prevention structure in situ. The molding system1600may be opened to remove the molded product. In some embodiments, any extra mold material formed on the molded product may be removed (e.g., cut) from the molded product prior to securing the sole plate to an upper to form an article of footwear.

Mold materials for a molding process in the molding system ofFIGS. 16-18may be any known or later developed molding materials suitable for a desired ground surface material accumulation prevention structure. In some embodiments the mold material may be a thermoforming or thermosetting material. As shown inFIGS. 16-18, in some embodiments the mold material may be in the form of a sheet of mold material. In some embodiments, the molding material may include, but is not limited to, any one or more of the following materials: natural or synthetic rubber, hard foam, plastics, polymers, nylon, polyurethane, thermoplastic polyurethane (TPU), as well as any other deformable or rigid materials. However, it will be understood that any other materials could be used as the molding material. In some embodiments the sheet of mold material1630and optional wear resistant surface treatment material1336may be different mold materials. In some embodiments the mold material may be mold compatible with a material of sole plate16. Those skilled in the art readily will be able to select various combinations of mold materials suitable for a particular application.

Alternative Molding System for Molding Integral Sole Plate and Ground Surface Material Accumulation Prevention Structure

FIG. 19illustrates an alternative embodiment of a molding system for molding a sole plate for an article of footwear, where the sole plate includes an integral ground material accumulation prevention structure.

FIG. 19illustrates an embodiment of molding system1600in an exploded, open mold configuration. As shown inFIG. 19, in some embodiments a sheet of mold material1630illustrated inFIG. 16may be replaced with one or more mold material blank1930. As shown inFIG. 19, in some embodiments a mold material blank1930may be pre-formed or pre-cut to provide a mold material blank that is sized and configured to correspond to a size and configuration of a target mold cavity. As shown inFIG. 19, in some embodiments molding system may include a first mold material blank1930sized and configured to conform to first mold cavity1616in the forefoot area18of sole plate16, and a second material blank1931sized and configured to conform to first mold cavity1618in the heel area20of sole plate16. In some embodiments, first mold material blank1930and second mold material blank1931may have a different size and configuration. In some embodiments, first mold material blank1930and second mold material blank1931may be formed of different mold materials.

Functional Characteristics and Operation

FIGS. 20 to 27illustrate exemplary functional characteristics and operation of ground surface material accumulation prevention structures of the present invention. As shown inFIGS. 20-27, in some embodiments ground surface material accumulation prevention structure may operate to prevent accumulation of ground surface material on a lower surface of an article of footwear in active use of the article of footwear.

FIG. 20is a schematic snap shot view of an athlete, illustrating functional characteristics and operation of ground surface material accumulation prevention structure of the present invention in active use of an article of footwear. InFIG. 20, an athlete is shown in stride during normal athletic activity, such as running, playing soccer or another sport, etc., on a ground surface. The ground surface may include compactable ground surface material, such as mud, gravel, sand, clay, slush (snow, ice, or frost), etc., or various combinations thereof. InFIG. 20, the athlete's left foot is extended in front of the athlete's body in a heel strike state of a stride cycle, where a strike force and weight of the athlete is being transmitted to the ground surface. In this manner, a compression force between the sole16of the article of footwear10and the ground surface progressively is generated in the heel region20to the toe region24of the article of footwear10. InFIG. 20, the athlete's right foot is extended in back of the athlete's body in a toe off state of a stride cycle, where a force and weight of the athlete generally is released. In this manner, a compression force between the sole16of the article of footwear10and the ground surface progressively is released from the heel region20to the toe region24of the article of footwear10.

InFIG. 20, the heel strike state is shown in enlarged view in the upper right hand portion of the figure, and the toe off state is shown in enlarged view in the upper left hand portion of the figure. Although functional characteristics and operation of the ground surface material accumulation prevention structure12are described inFIG. 20with respect to a stride cycle including heel strike and toe off states, this stride cycle is exemplary only to illustrate different functional characteristics and operation states of ground surface material accumulation prevention structure12in active use of the article of footwear. Those skilled in the art readily will appreciate that the ground surface material accumulation prevention structure12may be used with similar functional characteristics and operation in other stride cycles or methods of active use of the article of footwear, such as running on the balls of the feet, running with a lateral midfoot strike cycle, trapping a soccer ball, etc.

In the exemplary stride cycle shown inFIG. 20, a first article of footwear (left shoe)10is shown with three ground surface material accumulation prevention structures12in three different operation states associated with a heel strike state of the stride cycle. A first ground surface material accumulation prevention structure12located in the toe region24of the forefoot region18is shown in a fully non-compressed state, where the exposed surface of the reaction element of the ground surface material accumulation prevention structure12is fully extended in a dome shape. A second ground surface material accumulation prevention structure12located in the balls of the foot region26of the forefoot region18is shown in a partially compressed state, where the exposed surface of the reaction element of the ground surface material accumulation prevention structure12is partially collapsed in a dimpled dome shape. A third ground surface material accumulation prevention structure12located in the heel region20is shown in a fully compressed state, where the exposed surface of the reaction element of the ground surface material accumulation prevention structure12is fully collapsed to lay substantially flat proximal the lower surface of the sole of the article of footwear.

In the exemplary stride cycle shown inFIG. 20, a second article of footwear (right shoe)10is shown with three ground surface material accumulation prevention structures12in three different operation states associated with a toe off state of the stride cycle. A first ground surface material accumulation prevention structure12located in the toe region24of the forefoot area18is shown in a fully compressed state, where the exposed surface of the reaction element of the ground surface material accumulation prevention structure12is fully collapsed to lay substantially flat proximal the lower surface of the sole of the article of footwear. In this state, a thrust force and weight of the athlete is being transferred to the ground surface. A second ground surface material accumulation prevention structure12located in the balls of the foot region26of the forefoot region18is shown in a partially compressed state (partially non-compressed or released state), where the exposed surface of the reaction element of the ground surface material accumulation prevention structure12is partially collapsed (partially released) in a dimpled dome shape. And a third ground surface material accumulation prevention structure12located in the heel region20is shown in a fully non-compressed state (fully released state), where the exposed surface of the reaction element of the ground surface material accumulation prevention structure12is fully extended in a dome shape.

FIGS. 21 to 27illustrate functional characteristics and operation of a single ground surface material accumulation prevention structure with respect to compression forces progressively generated and released between the article of footwear and the ground surface, to prevent accumulation of ground surface material on the lower surface of the article of footwear in active use of the article of footwear. InFIGS. 21-27an exemplary ground surface material accumulation prevention structure is shown in sectional view to illustrate physical deformation associated with external compression forces applied to, and internal reactive forces generated by, a reactive element of the ground surface material accumulation prevention structure.

FIG. 21is a schematic sectional view of a ground surface material accumulation prevention structure illustrating a pre-surface strike state in an operation cycle of the structure. In this state the article of footwear and ground surface material accumulation prevention structure may be descending toward the ground surface, as indicated by arrow2110. As shown inFIG. 21, in this state the reactive element42of the ground surface material accumulation prevention structure12is fully non-compressed and extended in a dome shape.

FIG. 22is a schematic sectional view of a ground surface material accumulation prevention structure illustrating an initial surface strike state in an operation cycle of the structure. In the initial surface strike state ofFIG. 22, one or more ground surface traction element17may contact the ground surface in advance of the ground surface material accumulation prevention structure12, which is disposed above the ground surface and is fully extended in a dome shape. In this state, the ground surface traction elements17may begin to displace ground surface material, as indicated by small solid arrows2210. In this manner, a portion of ground surface material may be displaced into a space2212located under the ground surface material accumulation prevention structure12between the ground surface material accumulation prevention structures17. Those skilled in the art readily will appreciate that the ground surface material, including displaced ground surface material, may begin to compact under the ground surface material accumulation prevention structure12.

FIG. 23is a schematic sectional view of a ground surface material accumulation prevention structure illustrating a partial ground penetration state in an operation cycle of the structure. In the partial ground penetration state ofFIG. 23, the lower surface32of the sole16of the article of footwear10begins to engage the ground surface with a compression force, as indicated by thick solid arrows2310. A source of the compression force may include various factors, such as a force of weight of the athlete, a heel strike force, a thrust force (e.g., from an athlete changing a direction of stride or from a toe off push), and the like. Ground surface material located below the ground surface material accumulation prevention structure12, including ground surface material displaced by a penetrating ground surface traction element17, may be compacted under the ground surface material accumulation prevention structure12by the compression force2310. In this manner the compression force2310may begin to create a layer of compacted surface material (indicated by dashed line)2312disposed on the exposed surface of the ground surface material accumulation prevention structure12.

In the partial ground penetration state illustrated inFIG. 23the exposed surface of the reactive element42of the ground surface material accumulation prevention structure12begins to deform by compression, e.g., to dimple. In this manner, a portion of energy generated by the compression force is absorbed by the reactive element42of the ground surface material accumulation prevention structure12; this absorbed energy may be expressed as a reactive force generated in the reactive element42that is biased to return the exposed surface of the reactive element42to a fully extended dome shape, as indicated by dashed arrows2314. The reactive force generated by compression of the reactive element42is small relative to the compression force2310between the sole16and the ground surface, as indicated inFIG. 23by the relative thickness of compression force arrows2310and reactive force arrows2310. The reactive force2314generated by the energy absorbed by the reactive element42need only be sufficient to return the exposed surface of the reactive element42to the fully extended dome shape upon release of the compression force2314, as discussed below. In this manner, energy of the athlete corresponding to the compression force2310is substantially transferred to the ground surface, with a portion of the energy being transferred to reactive element42of the ground surface material accumulation prevention structure12.

FIG. 24is a schematic sectional view of a ground surface material accumulation prevention structure illustrating a full ground penetration state in the operation cycle of the structure. In the full ground penetration state ofFIG. 24, the compression force2310at the ground surface material accumulation prevention structure12may be at a maximum, with maximum transmission of the energy from the athlete to the ground surface. As shown in the full ground surface penetration state ofFIG. 23, the compression force2310may be exerted across an entire surface area of the ground surface material accumulation prevention structure12. As shown inFIG. 23, the compression force2310may be substantially greater than the reaction force2312absorbed and stored in reaction element42of ground surface material accumulation prevention structure12. As shown inFIG. 24, in the full ground penetration state the layer of compacted ground surface material (indicated by dashed line)2312may be formed on the exposed surface of the reaction element42of the ground surface material accumulation prevention structure12.

FIG. 25is a schematic sectional view of a ground surface material accumulation prevention structure illustrating an initial release state in an operation cycle of the structure. As shown inFIG. 25, in the initial release state the sole16of the article of footwear may begin to lift off from the ground surface. As the sole16begins lift off from the ground surface, the layer of compacted ground surface material2312may begin to separate from the ground surface proper and become exposed, and a localized compaction force2310may begin to release. As the layer of compacted ground surface material2312becomes exposed and the localized compaction force2310is released, a portion of the reactive energy absorbed and stored in the reactive element42, expressed as reactive force2314, may begin to expand a portion of the exposed surface of the reactive element42to begin to return the portion of the exposed surface of the reactive element42to a non-compressed state, e.g., to an extended dome shape. In some embodiments the surface of the reactive element42may begin to move relative to the layer of compacted ground surface material2312and generate surface tension forces between the exposed surface of the reactive element42and the layer of compacted surface material. In some embodiments the exposed surface of the reactive element42may twist or shift to a new orientation relative to the layer of compacted ground surface material2312. In this manner, expansion of the portion of the exposed surface of the reactive element42may cause the layer of compacted ground surface material2312to begin to break apart into particles of ground surface material2510.

FIG. 26is a schematic sectional view of a ground surface material accumulation prevention structure illustrating a substantial release state in an operation cycle of the structure. As shown inFIG. 26, in the substantial release state the sole16continues to lift off from the ground surface proper. In this state a compression force2310may continue to be applied between the ground surface and at least one ground surface traction element17. In this state, reactive energy absorbed and stored in the reactive element42may continue to be expressed as a reactive force2314at the exposed surface of the reactive element42to expand the exposed surface of the reactive element42toward a fully non-compressed state. Continued expansion of the exposed surface of the reactive element42may continue to break apart the layer of compressed ground surface material into particles of ground surface material2510. In some embodiments, in response to release of the compression force2310, the reactive element42may ‘pop’ the exposed surface of the reactive element42to a substantially expanded, non-compressed state (e.g., to a fully expanded dome shape). In this manner, reactive energy absorbed and stored in the reactive element42may be transferred to the particles of ground surface material2510to expel particles of ground material2510from the exposed surface of the reactive element42, as indicated by arrows2610.

FIG. 27is a schematic sectional view of a ground surface material accumulation prevention structure illustrating a full release state in an operation cycle of the structure. In the full release state, the exposed surface of the reactive element42is fully extended in a dome shape, and the reactive energy absorbed and stored in the reactive element42from the compression force2310may be fully transferred from the reactive element42to particles of ground surface material2510, as indicated by arrows2610. In this manner, ground surface material may be prevented from accumulating on the lower surface32of the sole16of the article of footwear10in active use of the article of footwear10.

As discussed above, a ground surface material accumulation prevention structure of the present invention may operate to prevent onset of accumulation of ground surface material on a lower surface of a sole of an article of footwear in active use of the article of footwear. As illustrated inFIGS. 20-27, in some embodiments a ground surface material accumulation prevention structure may operate in association with a heel strike to toe off stride cycle in active use of the article of footwear. In some embodiments, a ground surface material accumulation prevention structure may operate in association with other active use of an article of footwear. Non-exhaustive examples include playing sports such as soccer, football, lacrosse, etc., as well as activities in snow, ice, and slush. Those skilled in the art readily will appreciate alternative active use of an article of footwear suitable for a ground surface material accumulation prevention structure of the present invention.

As discussed above, a ground surface material accumulation prevention structure of the present invention may operate to prevent accumulation of ground surface material by moving an exposed surface of a reactive element of the structure between a first position and a second position in response to a compression force applied to the reactive element in active use of the article of footwear. In some embodiments, a reactive element may move an exposed surface of the reactive element between a first state and a second state relative to the lower surface of the article of footwear, e.g., relative to one or more ground surface traction elements on the lower surface of the sole of the article of footwear. In some embodiments, a reactive element may move an exposed surface of the reactive element between a first orientation and a second orientation relative to the lower surface of the sole of the article of footwear, e.g., to twist relative to one or more ground surface traction elements on the lower surface of the sole of the article of footwear. In some embodiments, a reactive element may move an exposed surface of the reactive element between a first surface contour and a second surface contour different from the first surface contour. In some embodiments, a reactive element may move an exposed surface of the reactive element between a first position proximate the lower surface of the sole of the article of footwear and a second position further away from the lower surface of the sole of the article of footwear. In each case a reactive element may be configured to move an exposed surface of the reactive element relative to a layer of compacted ground surface material being formed adjacent the exposed surface in active use of an article of footwear, to facilitate breaking up the layer of compacted ground surface material into particles of ground surface material and discarding of the compacted ground surface material from the lower surface of the article of footwear in the active use of the article of footwear.

Functional, operational, and performance characteristics of a ground surface material accumulation prevention structure may be controlled by selecting materials and dimensional characteristics of the reactive element of the structure. A reactive force characteristic of the reactive element may be determined by controlling various factors, including a material composition of the reactive element, a desired rigidity of the reactive element, a strength of the cured/hardened molding material(s), a thickness of the exposed surface of a dome-shaped reactive element, a depth of the dome shaped reactive element, a size of the reactive element (e.g., radius or length and width), and an amount of molding material desired for making the reactive element (cost factors). Those skilled in the art readily will appreciate other factors in light of the present disclosure and a desired application and performance characteristics. Those skilled in the art readily will be able to determine a material composition, size, and configuration of a reactive element for achieving desired functional, operational, and performance characteristics in a ground surface material accumulation prevention structure.

Those skilled in the art readily will appreciate that each of the embodiments shown inFIGS. 1-27may have one or more advantages in a particular application. In some applications, one embodiment may have a more desired performance characteristic, such as providing a desired reactive force characteristic, providing a desired traction characteristic for a selected playing surface, or providing a desired safety characteristic. In some embodiments, one embodiment may have a more desired aesthetic characteristic than another embodiment. Those skilled in the art readily will be able to select an appropriate configuration for a desired application.