Patent Description:
Footwear typically includes a sole structure configured to be located under a wearer's foot to space the foot away from the ground. Sole structures in athletic footwear are configured to provide desired cushioning, motion control, and resiliency.

<CIT> describes a device having a stretching and/or expanding device (<NUM>) integrated in an elastic partial region of a lady's shoe sole (<NUM>) and acting transverse to a longitudinal extension of sole. Sole anchors are arranged in the front foot region of the sole oriented along the longitudinal direction of shoe. The device (<NUM>) includes an adjustable spacer (<NUM>), which is arranged between the anchors. The anchors are stressed with the spacer in its end regions, which are turned away from the toe tip by applying a pressure transverse to the longitudinal direction of shoe in order to alter the sole width.

Some activities are best performed with a relatively stiff sole structure, while others are best performed with a less stiff (e.g., more flexible) sole structure. A sole structure according to claim <NUM> is disclosed, with additional embodiments disclosed in the dependent claims <NUM>-<NUM>.

More particularly, a sole structure for an article of footwear comprises a first plate and a second plate. Both the first plate and the second plate extend longitudinally in a flexion region of the sole structure with the second plate disposed above the first plate in the flexion region. The second plate has a fixed portion fixed to the first plate, and has a free portion. A coupler is operatively connected to one of the first plate and the free portion of the second plate. The coupler is selectably movable transversely relative to the first plate and the second plate between a first position and a second position. The coupler is spaced apart from the other one of the first plate and the free portion of the second plate when the coupler is in the first position. The coupler operatively engages the other one of the first plate and the free portion of the second plate when the coupler is in the second position.

The plate assembly has a selectable binary stiffness because, with the coupler in the first position, the first plate and the second plate bend independently of one another, but when the coupler is in the second position, the first plate is operatively connected with the free portion of the second plate via the coupler, and the first plate and the second plate bend as a single unit. The bending stiffness of the plate assembly is greater when the coupler is in the second position, as a neutral bending axis of the plate assembly is between the first plate and the second plate, with the first plate bending in tension and the second plate bending in compression. Accordingly, a wearer of an article of footwear can selectively adjust the bending stiffness of a sole structure that includes the plate assembly by moving the coupler from the first position to the second position, or from the second position to the first position.

When the coupler is in the first position, the first plate has a portion in tension and a portion in compression during longitudinal bending of the sole structure at the flexion region. When the coupler is in the second position, the first plate is in tension and the second plate is in compression during longitudinal bending of the sole structure at the flexion region.

The second plate is spaced apart from the first plate by a vertical gap in the flexion region. For example, the sole structure further comprises stanchions extending from at least one of the first plate and the second plate across the vertical gap. The stanchions maintain the vertical gap between the first plate and the second plate during longitudinal bending of the sole structure in the flexion region.

In one or more examples, the stanchions include a medial set of stanchions extending adjacent a medial edge of the one of the first plate and the second plate to which the coupler is connected. The stanchions further include a lateral set of stanchions adjacent a lateral edge of the one of the first plate and the second plate to which the coupler is connected. The stanchions also include a central set of stanchions disposed between the medial set and the lateral set and extending from the other one of the first plate and the second plate than the medial set and the lateral set.

In one or more examples, each stanchion of the medial set and each stanchion of the lateral set has a groove at an inward side of the stanchion. Each stanchion of the central set has a medial lip at the medial side of the stanchion and a lateral lip at the lateral side of the stanchion. The medial lip interfits with the groove of the medial set and the lateral lip interfits with the groove of the lateral set.

In one or more examples, at the fixed portion of the second plate, a distal surface of the second plate has one of a protrusion and a recess. A proximal surface of the first plate has the other one of the protrusion and the recess. The protrusion fits into the recess. The recess may be an annular groove, and the protrusion may be an annular protrusion.

In one or more examples, a third plate is fixed to the first plate on the same side of the first plate as the second plate. The third plate is spaced longitudinally apart from the second plate by a longitudinal gap. The coupler is at least partially nested between the first plate and the third plate. The longitudinal gap exists at least during longitudinal bending of the sole structure over a flexion range, and the flexion range may be selected to be a greater range than is expected during use of the sole structure in a certain activity so that the longitudinal gap exists during the activity.

In one or more examples, the sole structure further comprises a midsole having a forefoot region, a midfoot region, and a heel region. The midsole overlies the first plate and the second plate. The midsole has an opening extending from a proximal surface of the midsole to a distal surface of the midsole in the forefoot region. The first plate and the second plate extend in the opening.

In one or more embodiments, the coupler is fixed to the first plate. The second plate has a protrusion with a wall at least partially facing the coupler. The coupler abuts the wall when the coupler is in the second position.

In one or more examples, the coupler includes a first link and a second link. The first link is pivotably connected to the first plate at a fixed pivot. The second link is pivotably connected to the first link at a movable pivot. The second link has a free end, and the movable pivot is disposed between the fixed pivot and the free end of the second link. The first link and the second link move transversely relative to the first plate at the movable pivot when the coupler moves from the first position to the second position. The free end of the second link is spaced apart from the free portion of the second plate when the coupler is in the first position, and operatively engages the second plate when the coupler is in the second position.

In one or more examples, at least one cable is secured to the coupler at the movable pivot. A medial portion of the at least one cable extends laterally-outward from the movable pivot beyond a medial edge of the first plate, and a lateral portion of the at least one cable extends laterally-outward from the movable pivot beyond a lateral edge of the first plate. The coupler is transversely movable from the first position to the second position by a laterally-outward force on one of the medial portion and the lateral portion of the at least one cable. The coupler is transversely movable from the second position to the first position by a laterally-outward force on the other of the medial portion and the lateral portion of the at least one cable.

The movable pivot may be transversely offset from both the fixed pivot and the free end of the second link toward one of the lateral edge and the medial edge of the first plate when the coupler is in the first position, and the movable pivot may be transversely offset from both the fixed pivot and the free end of the second link toward the other one of the lateral edge and the medial edge of the first plate when the coupler is in the second position.

In some examples, an upper may be secured to the sole structure. The medial portion of the at least one cable may extend along a medial side of the upper, and the lateral portion of the at least one cable may extend along a lateral side of the upper.

In one or more examples, a sleeve may surround either or both of the medial portion and the lateral portion of the at least one cable. For example, an elastic sleeve may overlay the exterior of the upper, and be liftable away from the upper when a force with a laterally-outward component is applied to the sleeve and the at least one cable therewithin, moving the coupler from the first position to the second position, or from the second position to the first position.

In one or more examples, the coupler has a medial end extending laterally-outward of a medial edge of the first plate in both the first position and the second position, and a lateral end extending laterally-outward of a lateral edge of the first plate in both the first position and the second position. The medial end and the lateral end may thus be easily accessible to a wearer of an article of footwear with a sole structure that includes the plate assembly, enabling a quick adjustment of bending stiffness when desired, with the article of footwear remaining on the wearer's foot.

In one or more examples, the coupler has a protrusion extending toward the other one of the first plate and the second plate, and the other one of the first plate and the second plate has a protrusion extending toward the coupler. For example, each of the protrusion. The protrusion of the coupler is transversely offset from and spaced apart from the protrusion of the other one of the first plate and the second plate when the coupler is in the first position. The protrusion of the coupler is at least partially aligned with and abuts the protrusion of the other one of the first plate and the second plate when the coupler is in the second position.

For example, the coupler may have a first set of teeth extending longitudinally toward the other one of the first plate and the second plate, and the other one of the first plate and the second plate may have a second set of teeth extending longitudinally toward the coupler. The protrusion of the coupler may be one of the teeth of the first set, and the protrusion of the other one of the first plate and the second plate may be one of the teeth of the second set. The teeth of the first set are transversely offset from and spaced apart from the teeth of the second set when the coupler is in the first position. The teeth of the first set of teeth are at least partially aligned with and abut the teeth of the second set when the coupler is in the second position.

In one or more examples, a post extends from the one of the first plate and the second plate. The coupler has a slot extending through the coupler from a proximal surface of the coupler to a distal surface of the coupler. The post extends through the slot of the coupler. The post is at a first end of the slot when the coupler is in the first position. The post is at a second end of the slot opposite the first end when the coupler is in the second position. The coupler may have a tab extending into the slot such that the slot is narrowed at the tab. The post may be between the first end of the slot and the tab when the coupler is in the first position, and the post may be between the second end of the slot and the tab when the coupler is in the second position.

In one or more examples, the sole structure further comprises a midsole at least partially surrounding the first plate and the second plate. The midsole has a medial side wall with a medial opening. The midsole has a lateral side wall with a lateral opening. The coupler extends through both of the medial opening and the lateral opening in both the first position and the second position.

Referring to the drawings, wherein like reference numbers refer to like components throughout the views, <FIG> is a plan view (i.e., a top view) of a plate assembly <NUM> of a sole structure for an article of footwear. A sole structure <NUM> including the plate assembly <NUM> is shown in <FIG>, and an article of footwear <NUM> including the sole structure <NUM> is shown in <FIG>. The plate assembly <NUM> is configured to provide a selectable binary stiffness, adjustable by the wearer while the article of footwear <NUM> is on the foot. Accordingly, a change from a relatively low level of stiffness to a relatively high level of stiffness can be quickly and easily made by the wearer. For example, the relatively low level of stiffness may be desirable for certain activities, such as walking, while the relatively high level of stiffness may be desirable for other activities such as when taking a golf swing.

With reference to <FIG>, the plate assembly <NUM> includes a first plate <NUM>, a second plate <NUM>, and a third plate <NUM>. As used herein, the term "plate" refers to a member of a sole structure that is generally horizontally disposed when assembled in an article of footwear that is resting on the sole structure on a level ground surface, and is generally used to provide structure and form rather than cushioning. A plate need not be a single component but instead can be multiple interconnected components. Portions of a plate can be flat, and portions can be pre-formed with some amount of curvature and variations in thickness when molded or otherwise formed in order to provide a shaped footbed and/or increased thickness for reinforcement in desired areas. For example, in the plate assembly <NUM>, each of the first plate <NUM>, the second plate <NUM>, and the third plate <NUM> are discrete components. However, the first plate <NUM>, the second plate <NUM> and/or the third plate <NUM> could be integral portions of a single, unitary component, similar to the embodiment of <FIG>, such as if the first plate <NUM>, second plate <NUM>, and third plate <NUM> are three-dimensionally printed as a single component.

The first plate <NUM> has a forefoot region <NUM>, a midfoot region <NUM>, and a heel region <NUM>. The forefoot region <NUM>, midfoot region <NUM>, and heel region <NUM> correspond to and may be used to refer to like regions of the sole structure <NUM> and the article of footwear <NUM> and of any of the components thereof. The forefoot region <NUM> generally includes portions of the first plate <NUM> corresponding with the toes and the joints connecting the metatarsals with the phalanges of the human foot (interchangeably referred to herein as the "metatarsal-phalangeal joints" or "MPJ" joints). The midfoot region <NUM> generally includes portions of the first plate <NUM> corresponding with an arch area of the human foot, including the navicular joint. The heel region <NUM> generally includes portions of the first plate <NUM> corresponding with rear portions of a human foot, including the calcaneus bone, when the human foot is supported on the sole structure and is a size corresponding with the sole structure. The forefoot region <NUM>, the midfoot region <NUM>, and the heel region <NUM> may also be referred to as a forefoot portion, a midfoot portion, and a heel portion, respectively, and may also be used to refer to corresponding regions of an upper and other components of an article of footwear. The midfoot region <NUM> is disposed between the forefoot region <NUM> and the heel region <NUM>, such that the forefoot region <NUM> is forward of (i.e., anterior to) the midfoot region <NUM> and the heel region <NUM> is rearward of (i.e., posterior to) the midfoot region <NUM>.

The first plate <NUM> has a medial edge <NUM> and a lateral edge <NUM>, as best shown in <FIG>. The medial edge <NUM> and the lateral edge <NUM> extend along the forefoot region <NUM>, the midfoot region <NUM>, and the heel region <NUM>. The plate assembly <NUM> is for a right foot. It should be understood that a plate assembly for a left foot is a mirror image of the plate assembly <NUM>.

Both the first plate <NUM> and the second plate <NUM> extend longitudinally in a flexion region <NUM> of the sole structure. The plate assembly <NUM> has a longitudinal axis L, and both plates <NUM>, <NUM> extend along the longitudinal axis L. The second plate <NUM> is disposed above the first plate <NUM> in the flexion region <NUM>. The flexion region <NUM> is generally the region that corresponds to the metatarsal phalangeal joints (MPJ joints) of the foot. Accordingly, during dorsiflexion, the flexion region <NUM> flexes along the longitudinal axis L.

The second plate <NUM> has a fixed portion <NUM> fixed to the first plate <NUM>. More particularly, the fixed portion <NUM> is the portion of the second plate <NUM> that is anterior to the flexion region <NUM>. The fixed portion <NUM> is aligned with and then secured to a first portion <NUM> (see <FIG>) of the first plate <NUM> forward of the flexion region <NUM>. The fixed portion <NUM> can be aligned with the first portion <NUM> such as by fitting an annular protrusion <NUM> that extends from a distal surface <NUM> of the second plate <NUM> (see <FIG>) into an annular recess <NUM> in a proximal surface <NUM> of the first plate <NUM> (see <FIG>). The annular protrusion <NUM> and the annular recess <NUM> may be configured to provide an interference fit, so that the fixed portion <NUM> is secured to the first portion <NUM> via the interfitting protrusion <NUM> and recess <NUM>. Alternatively, the annular protrusion <NUM> may extend from the first plate <NUM>, and the annular recess <NUM> may be in the second plate <NUM>. The annular protrusion <NUM> and the annular recess <NUM> are elongated ovals that extend longitudinally and also extend transversely over more than half of the width of the first portion <NUM>, which helps to prevent any rotational displacement of the second plate <NUM> relative to the first plate <NUM> at the annular protrusion <NUM>. Alternatively, the annular protrusion <NUM> and the annular recess <NUM> may have other shapes that are not annular.

The second plate <NUM> is positioned over the first plate <NUM> via interfitting stanchions that extend in a vertical gap <NUM> (see <FIG>) that exists between the first plate <NUM> and the second plate <NUM> in the flexion region <NUM>. The plate assembly <NUM> is configured so that the vertical gap <NUM> is uniform in height over the flexion region <NUM>, or is at least sufficiently uniform such that the distal surface <NUM> of the second plate <NUM> is spaced apart from and does not come into contact with the proximal surface <NUM> of the first plate <NUM> during longitudinal bending in the flexion region <NUM>. Ensuring that the vertical gap <NUM> remains during longitudinal bending of the plate assembly <NUM> enables the bending stiffness of the plate assembly <NUM> to be controlled by the position of the coupler <NUM> described herein.

Stanchions 46A and 46B extend from the proximal surface <NUM> of the first plate <NUM> across the vertical gap <NUM>, and stanchions 46C extend from the distal surface <NUM> of the second plate <NUM> across the vertical gap <NUM> to help maintain the uniform vertical gap <NUM>. More specifically, a medial set of stanchions 46A extends adjacent the medial edge <NUM> of the first plate <NUM>, and a lateral set of stanchions 46B extend adjacent the lateral edge <NUM> of the first plate <NUM> as shown in <FIG>. A central set of stanchions 46C extends from the second plate <NUM> and is disposed between the medial set 46A and the lateral set 46B in the assembled plate assembly <NUM>. Alternatively, the medial set 46A and the lateral set 46B may extend from the distal surface <NUM> of the second plate <NUM>, and the central set 46C may extend from the proximal surface <NUM> of the first plate <NUM>. The stanchions 46A, 46B, 46C help to prevent buckling of the second plate <NUM> when the second plate <NUM> is under longitudinal compression during longitudinal bending as described herein.

The stanchions in each respective set 46A, 46B, 46C are spaced longitudinally apart from one another, and are transversely aligned with the stanchions of the other sets. The stanchions 46C interfit with the stanchions 46A, 46B to further position the second plate <NUM> relative to the first plate <NUM> in the flexion region <NUM>. More specifically, as best shown in <FIG>, each stanchion of the medial set 46A has a groove 48A at a laterally-inward side of the stanchion, and each stanchion of the lateral set 46B has a groove 48B at a laterally-inward side of the stanchion. Each stanchion of the central set 46C has a medial lip 50A at the medial side of the stanchion and a lateral lip 50B at the lateral side of the stanchion. The medial lip 50A interfits with the groove 48A of the medial set 46A and the lateral lip 50B interfits with the groove 48B of the lateral set 46B. As best shown in <FIG>, the grooves 48A, 48B and the transverse width of the stanchions 46C as well as the height of the stanchions 46C are such that transverse gaps 47A exist between the stanchions 46C and the stanchions 46A and 46B, and a vertical gap 47B exists between the stanchions 46C and the proximal surface of the first plate <NUM>. This enables some longitudinal movement of the second plate <NUM> relative to the first plate <NUM> in the flexion region <NUM> during longitudinal bending of the plate assembly <NUM> when the coupler <NUM> is in the first position. As best shown in <FIG> and <FIG>, a pair of stanchions 46D extending from the first plate <NUM> interfit with a stanchion 46D extending from the second plate <NUM> with lips 50C of the stanchion 46E fitting in grooves 48D of the stanchions 46D. The grooves 48D and lips 50C as well as the height of the stanchion 46D are such that transverse gaps exist between the stanchions 46D and the stanchion E, and a vertical gap exists between the stanchion 46E and the proximal surface of the first plate <NUM> to enable some longitudinal movement of the second plate <NUM> relative to the first plate <NUM> in the flexion region <NUM> during longitudinal bending of the plate assembly <NUM> when the coupler <NUM> is in the first position.

When the recess <NUM> and protrusion <NUM> are interfit, the lips 50A, 50B of the stanchions 46C are interfit to the grooves 48A, 48B of the stanchions 46A, 46B, and the lips 50C of stanchion 46E are interfit with grooves 48D of stanchions 46D, the second plate <NUM> is properly positioned over the first plate <NUM>. In this position, through-holes <NUM> of the first plate <NUM> (see <FIG>) align with through-holes <NUM> of the second plate <NUM> (see <FIG>). Rivets, adhesive, or other securement modes may be used at the aligned through-holes to fix the fixed portion <NUM> of the second plate <NUM> to the first plate <NUM>.

With reference to <FIG> and <FIG>, the second plate <NUM> has a free portion <NUM> that is disposed rearward of the flexion region <NUM> when the fixed portion <NUM> of the second plate <NUM> is fixed to the first portion <NUM> of the first plate <NUM>. The free portion <NUM> is referred to as "free" because it is not fixed relative to an underlying portion of the first plate <NUM> when the coupler <NUM> is in a first position. As further disclosed herein, this allows the first plate <NUM> and the second plate <NUM> to bend each with its own neutral bending axis 66A, 66B respectively (shown in <FIG>) during longitudinal bending of the plate assembly <NUM> when not operatively connected by the coupler <NUM>. When the coupler <NUM> is moved to the second positon and operatively engages the second plate <NUM>, however, the free portion <NUM> is longitudinally fixed relative to the underlying portion of the first plate <NUM>, and the plate assembly <NUM> bends as a single unit with a single neutral bending axis 66C (shown in <FIG>) and a significantly greater bending stiffness.

Referring to <FIG>, a transversely movable coupler <NUM> is selectively movable between a first position of <FIG> and <FIG> and a second position of <FIG> and <FIG>. In the first position, when the plate assembly <NUM> bends along the longitudinal axis L at the flexion region <NUM>, each plate <NUM>, <NUM> bends independently of one another, and the bending stiffness of the plate assembly <NUM> in the flexion region <NUM> is associated with the sum of the bending stiffness of the first plate <NUM> and the bending stiffness of the second plate <NUM>. Stated differently, a neutral bending axis 66A extends through the first plate <NUM> and a separate neutral bending axis 66B extends through the second plate <NUM>, as shown in <FIG>, when the coupler <NUM> is in the first position. A portion 68A of the first plate <NUM> above the neutral axis 66A is subject to compression and a portion 69A of the first plate <NUM> below the neutral axis 66A is subject to tension during longitudinal bending of the plate assembly <NUM> along the longitudinal axis L at the flexion region <NUM> when the coupler <NUM> is in the first position. A portion 68B of the second plate <NUM> above the neutral axis 66B is subject to compression and a portion 69B of the second plate <NUM> below the neutral axis 66B is subject to tension during longitudinal bending of the plate assembly <NUM> along the longitudinal axis L at the flexion region <NUM> when the coupler <NUM> is in the first position.

With the coupler <NUM> in the first position, the bending stiffness of each plate <NUM>, <NUM> is proportional to its moment of inertia about the fixed portions <NUM>, <NUM>. Generally, the longitudinal bending stiffness of a plate is directly proportional to the moment of inertia (I) of the plate, with bending stiffness increasing linearly as moment of inertia increases. Equation <NUM> is the moment of inertia I of a plate:<MAT> where b is the width of the plate, and h is the height of the plate. Accordingly, the bending stiffness of a plate is proportional to the cube of its height.

When the coupler <NUM> is in the first position, the bending stiffness of the plate assembly <NUM> is associated with the height H1 of the first plate <NUM>, and the height H2 of the second plate <NUM> in the flexion region <NUM>. The height of the stanchions extending from the plates <NUM>, <NUM> do not influence the bending stiffness as they are not fixed to the neighboring plate.

When the coupler <NUM> effectively couples the second plate <NUM> to the first plate <NUM> when in the second position so that the stiffness of the plate assembly <NUM> is correlated with the overall height H3 of the plate assembly <NUM> from the proximal surface <NUM> of the second plate <NUM> to the distal surface <NUM> of the first plate <NUM>. When the coupler <NUM> is in the second position, the first plate <NUM> is in tension and the second plate <NUM> is in compression during longitudinal bending of the plate assembly <NUM> at the flexion region <NUM> over the flexion range.

The coupler <NUM> is operatively connected to the first plate <NUM> and is disposed adjacent to the free portion <NUM> of the second plate <NUM>. As best shown in <FIG>, the coupler <NUM> includes a first link <NUM> and a second link <NUM>. The first link <NUM> has a fixed end <NUM> pivotably connected to the first plate <NUM> at a fixed pivot <NUM>, best shown in <FIG> and <FIG>. For example, a pin <NUM> extends downward from the link <NUM> into an opening <NUM> of the first plate <NUM>, establishing a fixed pivot axis, also referred to as a fixed pivot <NUM> as best shown in <FIG>, <FIG>, and <FIG>.

The second link <NUM> is pivotably connected to the first link <NUM> at a movable pivot <NUM>. For example, as shown in <FIG>, an end 70A of the first link <NUM> is a circular head with a central opening. The circular head of the end 70A is approximately one half the height of the body 70B of the link <NUM>. The second link <NUM> also has an end 78A with a circular head having a central opening, with the circular head of the end 78A approximately half the height of the body 78B of the second link <NUM>. The ends 70A, 78A heads are stacked on one another with the openings aligned, defining a movable pivot with a pivot axis <NUM>.

The second link <NUM> also has a free end <NUM>. The free end <NUM> has a pin <NUM> extending from its distal surface. The pin <NUM> is received in a slot <NUM> that extends through the first plate <NUM> as best shown in <FIG> and <FIG>. The free end <NUM> is referred to as "free" because its longitudinal position relative to the first plate <NUM> can vary along the length of the slot <NUM> as the pin <NUM> rides in the slot <NUM>. In contrast, the fixed end <NUM> is fixed in a longitudinal position relative to the first plate <NUM> at the fixed pivot <NUM>. The movable pivot <NUM> is between the fixed pivot <NUM> and the free end <NUM> of the second link <NUM> in the longitudinal direction, both when the coupler <NUM> is in the first position and when the coupler <NUM> is in the second position as shown in <FIG> and <FIG>.

The plate assembly <NUM> includes a third plate <NUM> disposed above and fixed to the first plate <NUM> on the same side of the first plate <NUM> as the second plate <NUM> (i.e., on the proximal side in <FIG>). For example, through-holes <NUM> of the third plate <NUM> (shown in <FIG>) align with through-holes <NUM> of the first plate <NUM> (shown in <FIG>), and rivets, adhesive, or other connecting modes may be used to join the third plate <NUM> to the first plate <NUM> at the aligned through-holes. The coupler <NUM> is at least partially nested between the first plate <NUM> and the third plate <NUM>. The third plate <NUM> is spaced longitudinally apart from the free end <NUM> of the second plate <NUM> at a longitudinal gap <NUM>. The width of the longitudinal gap <NUM> is selected so that the gap <NUM> remains open over a flexion range that is at least as great as the range of flexion expected during various activities. For example, the gap <NUM> is configured to remain open over a range of flexion of <NUM> degrees, with the flex angle measured between a level ground plane and the longitudinal axis L at a rearward extent of the flexion region <NUM> when the heel region <NUM> is lifted and the sole structure <NUM> remains in contact with the ground plane. This range of flexion is greater than expected during walking while wearing the article of footwear <NUM>. Accordingly, with the coupler <NUM> in the first position, the bending stiffness of the plate assembly <NUM> will remain at the relatively low level associated with the first position of the coupler <NUM> throughout the walking stride.

As shown in <FIG>, <FIG>, a cable <NUM> is secured to the coupler <NUM> at the movable pivot <NUM>. The cable <NUM> includes a medial portion 88A that extends laterally-outward from the movable pivot <NUM> beyond the medial edge <NUM> of the first plate <NUM>, and a lateral portion 88B that extends laterally-outward from the movable pivot <NUM> beyond the lateral edge <NUM> of the first plate <NUM>. Although the portions 88A, 88B are shown extending straight outward in <FIG>, the cable <NUM> is flexible, as indicated in <FIG>, and the portions 88A, 88B may be routed as desired, such as upward along an upper <NUM> of the article of footwear <NUM>, as further described with respect to <FIG>. In <FIG>, the portions 88A, 88B are threaded through the stacked openings of the links <NUM>, <NUM> at the movable pivot <NUM>, and the respective ends 90A, 90B of the portions 88A, 88B are shown bent to indicate that the portions 88A, 88B are secured to the links <NUM>, <NUM> at the movable pivot <NUM>. The ends 90A, 90B may be knotted, tied together, or tied to the portions 88A, 88C to maintain the portions 88A, 88B of the cable <NUM> secured to the coupler <NUM> at the movable pivot <NUM>. The cable <NUM> may be a single cable with the portions 88A, 88B part of a unitary loop extending within the upper <NUM>, such as shown and described with respect to <FIG>, or the portions 88A, 88B may be separate cables that extend upward along the respective medial and lateral sides of the upper <NUM> to be pulled separately to move the coupler <NUM>.

The first link <NUM> and the second link <NUM> move transversely relative to the first plate <NUM> at the movable pivot <NUM> when the coupler <NUM> is selectively moved from the first position of <FIG> to the second position of <FIG>. The free end <NUM> of the second link <NUM> is spaced apart from the second plate <NUM> when the coupler <NUM> is in the first position. For example, as shown in the bottom view of <FIG>, the free end <NUM> is partially under the free portion <NUM> of the second plate <NUM>, but the end surface <NUM> of the free end <NUM> of the link <NUM> (best shown in <FIG>) is not in contact with the second plate <NUM>. Accordingly, when the plate assembly <NUM> bends during dorsiflexion, the free portion <NUM> of the second plate <NUM> can travel in a longitudinal gap <NUM>.

The coupler <NUM> is transversely movable from the first position of <FIG> to the second position of <FIG> by a laterally-outward force F1, indicated in <FIG>, applied on the medial portion 88A of the cable <NUM>. The coupler <NUM> is transversely movable from the second position to the first position by a laterally-outward force F2 on the lateral portion 88B of the cable <NUM>. The cable <NUM> extends out of the bottom of the stacked links <NUM>, <NUM>, as shown in <FIG>. The first plate <NUM> has openings through which the cable <NUM> extends downward from the movable pivot <NUM>, and the cable <NUM> then extends laterally outward in channels <NUM> formed by the first plate <NUM> on the bottom of the first plate <NUM> as best shown in <FIG>. This helps to restrain the cable <NUM> and guide its movement in the lateral direction during a switch between the first position and the second position of the coupler <NUM>. Vertical walls <NUM>, <NUM> of the first plate <NUM> limit transverse movement of the coupler <NUM> toward the lateral edge <NUM> and establish the first position of the coupler <NUM> when the coupler <NUM> abuts the walls <NUM>, <NUM> as shown in <FIG>. Vertical walls <NUM>, <NUM> of the first plate <NUM> limit transverse movement of the coupler <NUM> toward the medial edge <NUM> and establish the second position of the coupler <NUM> shown in <FIG>. A rounded wall between vertical walls <NUM>, <NUM> receives the heads of the links <NUM>, <NUM> at the movable pivot <NUM> in the first position. A rounded wall between vertical walls <NUM>, <NUM> receives the heads of the links <NUM>, <NUM> at the movable pivot <NUM> in the second position.

The angle A1 between the walls <NUM>, <NUM> (shown in <FIG>) is less than the angle A2 between the walls <NUM>, <NUM> (shown in <FIG>). Because the fixed end of the link <NUM> remains in one longitudinal position relative to the first plate <NUM> at all positions of the coupler <NUM>, the free end <NUM> of the second link <NUM> will be moved forward in the slot <NUM> in the second position relative to the first position. The distal surface of the second plate <NUM> has a downward-extending protrusion <NUM> with a rear-opening notch <NUM> at the free end <NUM>. A plurality of buttresses <NUM> extend downward from the second plate <NUM>, and extend forward from the protrusion <NUM> to support the free portion <NUM> and inhibit buckling of the free portion <NUM>.

The angle A2, the length of the links <NUM>, <NUM> and the position of the notch <NUM> are selected so that the surface <NUM> of the free end <NUM> abuts the second plate <NUM> at a wall <NUM> of the notch <NUM> when the coupler <NUM> is in the second position. This abutment is referred to as the coupler <NUM> operatively engaging the second plate <NUM> because, when the plate assembly <NUM> bends longitudinally with the coupler <NUM> abutting the second plate <NUM>, the second plate <NUM> cannot slide longitudinally relative to the first plate <NUM> and the plates <NUM>, <NUM> are connected to bend as a single unit with a bending stiffness proportional to the inertia of the plate assembly <NUM> according to Equation <NUM> above, with the height h being the total height H3 of the plate assembly <NUM> from the proximal surface <NUM> of the second plate <NUM> to the distal surface <NUM> of the first plate <NUM>, as shown in <FIG>. More specifically, the plate assembly <NUM> has a single neutral bending axis 66C. Because the second plate <NUM> is above the neutral bending axis, it is entirely in compression, while the first plate <NUM> below the neutral bending axis 66C is entirely in tension. The height H3 is significantly greater than the height H1 and the height H2, and the bending stiffness of the plate assembly <NUM> with the coupler <NUM> in the second position is likewise significantly greater than when the coupler <NUM> is in the first position.

As is apparent in <FIG> and <FIG>, the movable pivot <NUM> is transversely offset from both the fixed pivot <NUM> and the free end <NUM> of the second link <NUM> toward the lateral edge <NUM> when the coupler <NUM> is in the first position, and the movable pivot <NUM> is transversely offset from both the fixed pivot <NUM> and the free end <NUM> of the second link <NUM> toward the medial edge <NUM> of the first plate <NUM> when the coupler <NUM> is in the second position. Both the first position and the second position of the coupler <NUM> may be referred to as over-center positions, as the coupler <NUM> must pass through a straight state (in which the links <NUM>, <NUM> are <NUM> degrees apart from one another (i.e., extend along a straight line) in transitioning from the first position to the second position or from the second position to the first position. The walls <NUM>, <NUM> help to support the links <NUM>, <NUM>, acting as reaction surfaces for the links <NUM>, <NUM> when the coupler <NUM> is in the second position, providing more stability to the coupler <NUM> than if the coupler <NUM> was subjected to compressive force in the straight position.

Although the fixed portion <NUM> is shown fixed forward of the flexion region <NUM>, in an alternative embodiment, the second plate <NUM> can be configured so that a fixed portion is disposed rearward of the flexion region <NUM>, and the free portion and the coupler <NUM> are disposed forward of the flexion region. As another alternative embodiment, the components of the plate assembly <NUM> can be configured so that the fixed pivot <NUM> of the coupler <NUM> could be secured to the second plate <NUM>, and the free end <NUM> of the link <NUM> can be configured to operatively engage a wall of the first plate <NUM> when the coupler <NUM> is in the second position.

<FIG> shows the plate assembly <NUM> when assembled with other components of the sole structure <NUM>. For example, the sole structure <NUM> includes a midsole <NUM> having a forefoot region <NUM>, a midfoot region <NUM>, and a heel region <NUM>. The midsole <NUM> has an opening <NUM> extending from a proximal surface <NUM> of the midsole to a distal surface <NUM> of the midsole in the forefoot region <NUM>. The midsole <NUM> extends over the plate assembly <NUM> in the heel region <NUM> and the midfoot region <NUM> such that it overlies the first plate <NUM> and the second plate <NUM>. In the forefoot region <NUM>, the first plate <NUM> and the second plate <NUM> extend in the opening <NUM>. This avoids stacking the midsole <NUM> entirely above the plate assembly <NUM> in the forefoot region <NUM>, preventing an excessive vertical height of the sole structure <NUM> in the forefoot region <NUM>. Generally, sole structures are configured to have a lower overall height in the forefoot region <NUM> than in the heel region <NUM>.

<FIG>, <FIG>, and <FIG> show a multi-piece outsole <NUM> secured to the distal surface of the first plate <NUM> and to the bottom surface of the midsole <NUM>. As best shown in <FIG>, the outsole <NUM> includes a first portion 130A that extends in the forefoot region <NUM>, the midfoot region <NUM>, and the heel region <NUM>, and a discrete second portion 130B that extends only in the heel region <NUM>. In the forefoot region <NUM> and the midfoot region <NUM>, the first portion 130A extends laterally-outward of the medial edge <NUM> and the lateral edge <NUM> of the first plate <NUM>. Lateral cutouts <NUM> are provided at both the lateral side and the medial side of the first portion 130A in the flexion region <NUM>, and extend from the respective side past the longitudinal axis L of the sole structure <NUM>. The lateral cutouts <NUM> ensure that, during longitudinal bending, the outsole portion 130A does not significantly contribute to the bending stiffness of the sole structure <NUM> at the flexion region <NUM>, so that the bending stiffness of the sole structure <NUM> is mainly dependent upon the plate assembly <NUM> in the flexion region <NUM>. Similarly, the first portion 130A is separated from the second portion 130B by a gap <NUM> in the heel region <NUM>. The gap <NUM> promotes torsional flexibility of the outsole <NUM>. Fins <NUM> extend downward from the outsole <NUM> for increased traction and may aid in minimizing twisting of the article of footwear <NUM> during the backswing and downswing stages of a golf swing. The fins <NUM> are arranged on either side of a groove <NUM> in the forefoot and midfoot regions of the first portion 130A.

As best indicated in <FIG> and <FIG>, the medial and lateral cable portions 88A, 88B extend laterally-outward from the sole structure <NUM> in the channels <NUM> shown in <FIG> between a distal surface of the first plate <NUM> and a proximal surface of the first portion 130A of the outsole <NUM>. <FIG> also indicates the cable portion 88A, 88B extending below the first plate <NUM>.

The cable <NUM> may be accessible to the wearer in various positions. In one example, the cable <NUM> is a unitary cable, as shown in <FIG> and <FIG>. For example, the article of footwear <NUM> includes an upper <NUM> secured to the midsole <NUM> to define a foot-receiving cavity <NUM> for receiving and supporting a wearer's foot on the sole structure <NUM>. The medial portion 88A of the cable <NUM> extends along a medial side <NUM> of the upper <NUM>, and the lateral portion 88B of the cable <NUM> extends along a lateral side <NUM> of the upper <NUM>. An elastic sleeve <NUM> surrounds the medial portion 88A and the lateral portion 88B. The elastic sleeve <NUM> may be secured to a lower portion of the upper <NUM> by being positioned laterally inward of the midsole <NUM> as indicated in <FIG>.

The elastic sleeve <NUM> may be liftable away from the exterior surface of the upper <NUM> by an outward force having a lateral component in order to tension either the medial portion 88A or the lateral portion 88B to switch the position of the coupler <NUM>. For example, as shown in <FIG>, a force FM may be applied by grabbing and lifting the elastic sleeve <NUM> to the position <NUM> at the medial side <NUM> of the upper <NUM>. The force FM has a laterally-outward component that pulls the medial portion 88A of the cable <NUM> laterally outward, moving the coupler <NUM> from the first position to the second position, as described with respect to <FIG> and <FIG>. Similarly, a force FL applied by grabbing and lifting the elastic sleeve <NUM> at the lateral side <NUM> of the upper <NUM> to the position <NUM> has a laterally-outward component that pulls the lateral portion 88B of the cable <NUM> laterally outward, moving the coupler <NUM> from the second position to the first position, as described with respect to <FIG> and <FIG>. When not being pulled, the cable <NUM> can have some slack within the elastic sleeve <NUM>.

In some embodiments, the medial portion 88A and the lateral portion 88B can be two separate cables. In such embodiments, the separate cables could be tied to one another in the sleeve <NUM>. Alternatively, the separate cables could each be secured to the upper <NUM>, such as by extending through separate eyelets of the upper, or by securing to other lacing or tensioning elements provided on the upper. The separate cables would function in the same manner as described to move the movable joint <NUM> of the coupler <NUM> transversely under a laterally-outward force at the cable on the medial side of the upper or on the cable at the lateral side of the upper.

<FIG> show another embodiment of a plate assembly <NUM> that is part of a sole structure <NUM> (shown in <FIG>) for an article of footwear. The plate assembly <NUM> includes a first plate <NUM>, a second plate <NUM>, and a third plate <NUM> that function in the same manner as described with respect to the first plate <NUM>, the second plate <NUM>, and the third plate <NUM> of the plate assembly <NUM>. The plate assembly <NUM> has a flexion region <NUM>, and a vertical gap <NUM> as described with respect to plate assembly <NUM>. A longitudinal gap <NUM> exists between the second plate <NUM> and the third plate <NUM> and remains open over a range of flexion of the plate assembly <NUM>.

The plate assembly <NUM> includes a coupler <NUM> that is selectively movable transversely relative to the first plate <NUM> and the second plate <NUM> between a first position (shown in <FIG> and <FIG>) and a second position (shown in <FIG>). The first position establishes a first, relatively low bending stiffness and the second position establishes a second, relatively high bending stiffness, respectively, of the plate assembly <NUM> under longitudinal bending in the flexion region <NUM>. The coupler <NUM> has a medial end 288A that extends laterally-outward of the medial edge <NUM> of the first plate <NUM> in both the first position and the second position, and a lateral end 288B that extends laterally-outward of a lateral edge <NUM> of the first plate <NUM> in both the first position and the second position, as is apparent in <FIG> and <FIG>.

Similar to coupler <NUM>, the coupler <NUM> is operatively connected to the first plate <NUM> as shown in <FIG>, such that it is disposed adjacent a free portion <NUM> of the second plate <NUM>, shown in <FIG>. A post <NUM> extends upward from a proximal surface of the first plate <NUM>. The coupler <NUM> has a slot <NUM> extending through the coupler <NUM> from a proximal surface <NUM> of the coupler <NUM> shown in <FIG> to a distal surface <NUM> of the coupler <NUM> shown in <FIG>. The post <NUM> extends through the slot <NUM>. Moreover, the third plate <NUM> is secured to the first plate <NUM> so that the coupler <NUM> is nested between the plates <NUM>, <NUM>.

The coupler <NUM> has a tab <NUM> extending into the slot <NUM> such that the slot is narrowed at the tab. The tab <NUM> helps to retain the coupler <NUM> in the selected position, and may provide tactile feedback as to when the position is achieved. The post <NUM> is between the first end 257A of the slot <NUM> and the tab <NUM> when the coupler <NUM> is in the first position of <FIG>. The post <NUM> is between the second end 257B of the slot <NUM> and the tab <NUM> when the coupler <NUM> is in the second position of <FIG>.

The coupler <NUM> is selectively movable transversely relative to the first plate <NUM> and the second plate <NUM> from the first position to the second position by applying a laterally inward force FI1 on the end 288B, represented in <FIG>. Alternatively or in addition, a laterally outward force FO1 may be applied to the end 288A to move the coupler <NUM> from the first position to the second position. One or both of these forces may be applied manually. Alternatively, the laterally inward force FI1 on the end 288B may be applied with the opposite foot of the wearer, for example.

To selectively move the coupler <NUM> from the second position to the first position, a laterally inward force FI2 may be applied on the end 288A, represented in <FIG>. Alternatively or in addition, a laterally outward force FO2 may be applied to the end 288B to move the coupler <NUM> from the first position to the second position. One or both of these forces may be applied manually. Alternatively, the laterally inward force on the end 288A may be applied with the opposite foot of the wearer, for example.

As shown in <FIG>, the coupler <NUM> is spaced apart longitudinally from the second plate <NUM> when the coupler <NUM> is in the first position such that the second plate <NUM> bends separately from the first plate <NUM> during longitudinal bending of the sole structure <NUM> at the flexion region <NUM> over a flexion range, such as a flexion range of <NUM> to <NUM> degrees. The coupler <NUM> has a first set of teeth 267A, 267B that extend longitudinally toward the second plate <NUM>. Each of the teeth 267A, 267B may be referred to as a protrusion. The second plate <NUM> has a second set of teeth 277A, 277B extending longitudinally toward the coupler <NUM>. Each of the teeth 277A, 277B may be referred to as a protrusion. The teeth 277A, 277B are part of a downward protrusion <NUM> at a distal surface <NUM> of the free portion <NUM>.

The teeth 267A, 267B of the coupler <NUM> are transversely offset from and spaced apart from the teeth 277A, 277B of the second plate <NUM> when the coupler <NUM> is in the first position, as shown in <FIG>. With the sets of teeth 267A, 267B and 277A, 277B offset from one another in this manner, the free end <NUM> of the second plate <NUM> is not subjected to compressive forces by the first plate <NUM>, as the teeth 267A, 267B can move forward between teeth 277A, 277B at least over the distance D between the wall <NUM> of the protrusion <NUM> and the forward end of the tooth 267A.

The teeth 267A, 267B are at least partially aligned with and abut the teeth 277A, 277B when the coupler <NUM> is in the second position, as shown in <FIG>. With the teeth 277A, 277B abutting teeth 267A, 267B, the coupler <NUM> is operatively engaged with the second plate <NUM>. Referring to <FIG>, the first plate <NUM> has a wall <NUM> with a vertically-extending surface <NUM> disposed at a rear end of the coupler <NUM>. During longitudinal bending of the plate assembly <NUM>, the coupler <NUM> abuts both the surface <NUM> of the wall <NUM> of the first plate <NUM>, and the teeth 277A, 277B of the second plate <NUM>. The second plate <NUM> is thus fixed longitudinally relative to the first plate <NUM> in the flexion region <NUM>, and the second plate <NUM> bends only in compression while the first plate bends only in tension with a single neutral bending axis in a vertical position between the plates <NUM>, <NUM> during longitudinal bending of the sole structure <NUM> at the flexion region <NUM> over a flexion range.

When the coupler <NUM> is in the first position, the free end <NUM> of the second plate <NUM> is not engaged by the coupler <NUM>, and each of the first plate <NUM> and the second plate <NUM> has a separate neutral bending axis NB1, NB2, respectively. The portion of the first plate <NUM> above the neutral bending axis NB1 of the first plate is in compression, and the portion of the first plate <NUM> below the neutral bending axis NB1 is in tension. Likewise, the portion of the second plate <NUM> above the neutral bending axis NB2 is in compression, and the portion of the second plate <NUM> below the neutral bending axis NB2 is in tension.

When the coupler <NUM> is in the second position, a single neutral bending axis NB3 of the plate assembly <NUM> extends at a position between the first plate <NUM> and the second plate <NUM>, similar to the neutral bending axis 66C of <FIG>. The first plate <NUM> is in tension, and the second plate <NUM> is in compression. An increase in bending stiffness of the plate assembly <NUM> relative to the bending stiffness when the coupler <NUM> is in the first position is associated with this position of a single neutral bending axis.

<FIG> shows the sole structure <NUM> with the plate assembly <NUM> assembled with the midsole <NUM> and the outsole <NUM> described with respect to <FIG>. The midsole <NUM> at least partially surrounds the plate assembly <NUM>. The midsole <NUM> has an opening <NUM> from its proximal surface to its distal surface even larger than opening <NUM> of <FIG>, and each of the first plate <NUM> and the second plate <NUM> extend in the opening <NUM>. As best shown in <FIG>, a rear extent 222A of the opening <NUM> is forward of the coupler <NUM>, so that the midsole <NUM> has a recess <NUM>, rather than a through-hole, rearward of the rear extent 222A, with the third plate <NUM> in the recess <NUM> and a portion <NUM> of the midsole <NUM> underlying and supporting the third plate <NUM>.

The midsole <NUM> has a medial side wall 227A with a medial opening 229A, and a lateral side wall 227B with a lateral opening 229B. The openings 229A, 229B are configured to be of a sufficient size and the coupler <NUM> is configured to be of a sufficient length so that the coupler <NUM> extends through both of the medial opening 229A and the lateral opening 229B in both the first position and the second position of the coupler <NUM>.

<FIG> show another embodiment of a plate assembly <NUM> in which portions indicated as a first plate <NUM> and a second plate <NUM> are part of a unitary, one-piece component. A coupler <NUM> includes a first set of longitudinally extending teeth <NUM> that extend toward a second set of longitudinally extending teeth disposed on a free portion <NUM> of the second plate <NUM>. The coupler <NUM> can be selectively moved between a first position, shown in <FIG>, and a second position shown in <FIG>, similar to the coupler <NUM> of <FIG> and <FIG>. In the first position of the coupler <NUM>, the teeth <NUM> are transversely offset from the teeth <NUM> and the second plate <NUM> bends separately from the first plate, each plate <NUM>, <NUM> having a separate neutral bending axis, a portion in compression, and apportion in tension. In the second position of the coupler <NUM>, the teeth <NUM> are at least partially aligned with and abut the teeth <NUM> so that the coupler <NUM> is engaged with the second plate <NUM>, and the first plate and second plate bend as a unit, with a single neutral bending axis between the first plate and the second plate, the first plate <NUM> bending in tension and the second plate <NUM> bending in compression when the plate assembly <NUM> bends along its longitudinal axis L in the flexion region <NUM>.

Assembled, ready to wear footwear articles (e.g., shoes, sandals, boots, etc.), as well as discrete components of footwear articles (such as a midsole, an outsole, an upper component, etc.) prior to final assembly into ready to wear footwear articles, are considered and alternatively referred to herein in either the singular or plural as "article(s) of footwear" or "footwear".

The term "longitudinal" refers to a direction extending a length of a component. For example, a longitudinal direction of a shoe extends between a forefoot region and a heel region of the shoe. The term "forward" or "anterior" is used to refer to the general direction from a heel region toward a forefoot region, and the term "rearward" or "posterior" is used to refer to the opposite direction, i.e., the direction from the forefoot region toward the heel region. In some cases, a component may be identified with a longitudinal axis as well as a forward and rearward longitudinal direction along that axis. The longitudinal direction or axis may also be referred to as an anterior-posterior direction or axis.

The term "transverse" refers to a direction extending a width of a component. For example, a transverse direction of a shoe extends between a lateral side and a medial side of the shoe. The transverse direction or axis may also be referred to as a lateral direction or axis or a mediolateral direction or axis.

The term "vertical" refers to a direction generally perpendicular to both the lateral and longitudinal directions. For example, in cases where a sole is planted flat on a ground surface, the vertical direction may extend from the ground surface upward. It will be understood that each of these directional adjectives may be applied to individual components of a sole. The term "upward" or "upwards" refers to the vertical direction pointing towards a top of the component, which may include an instep, a fastening region and/or a throat of an upper. The term "downward" or "downwards" refers to the vertical direction pointing opposite the upwards direction, toward the bottom of a component and may generally point towards the bottom of a sole structure of an article of footwear.

Claim 1:
A sole structure for an article of footwear comprising:
a first plate (<NUM>) and a second plate (<NUM>) both extending longitudinally in a flexion region (<NUM>) of the sole structure (<NUM>) with the second plate (<NUM>) disposed above the first plate (<NUM>) in the flexion region (<NUM>);
wherein the second plate (<NUM>) has a fixed portion (<NUM>) fixed to the first plate (<NUM>), and has a free portion;
a coupler (<NUM>) operatively connected to one of the first plate (<NUM>) and the free portion (<NUM>) of the second plate (<NUM>);
wherein the coupler (<NUM>) is selectably movable transversely relative to the first plate (<NUM>) and the second plate (<NUM>) between a first position and a second position;
wherein the coupler (<NUM>) is spaced apart from the other one of the first plate (<NUM>) and the free portion (<NUM>) of the second plate (<NUM>) when the coupler (<NUM>) is in the first position; and
wherein the coupler (<NUM>) operatively engages the other one of the first plate (<NUM>) and the free portion (<NUM>) of the second plate (<NUM>) when the coupler (<NUM>) is in the second position,
characterized in that
the second plate (<NUM>) is spaced apart from the first plate (<NUM>) by a vertical gap (<NUM>) in the flexion region (<NUM>), and
in that <NUM> the sole structure further comprises stanchions (46A, 46B, 46C, 46D) extending from at least one of the first plate (<NUM>) and the second plate (<NUM>) across the vertical gap (<NUM>).