Variable friction sole for bowling and other shoes

Abstract

The effective friction of a shoe is adjusted by changing the angle of a portion of the sole, relative to the shoe centerline. In one embodiment, the heel is effectively hinged and an adjustment device is spaced from the hinge axis, whereby the wearer can hold the shoe in one hand and manually adjust an actuator connected to a drive member that increases or decreases the angle of the hinge. The hinge axis can be perpendicular to the centerline, either in the front of the heel with the drive member embedded in the back of the heel, or in the back of the heel, with the drive member embedded in the front of the heel. Angulation can be effected in the foresole, about an axis perpendicular to the shoe centerline, or about an axis that is parallel to but offset from the centerline.

Description

BACKGROUND OF THE INVENTION

The present invention pertains to performance footwear, especially walking and athletic shoes, and most particularly, bowling shoes.

As has been recognized for a number of years, and as discussed in U.S. Pat. No. 6,907,682, experienced bowlers often desire that each of the left and right shoes exhibit different characteristics, especially with respect to sliding friction on the smooth, wooden or synthetic floors typically present in the approach region of a bowling lane. Moreover, even for one or the other of the left or right shoe, such bowler typically desires a different sliding characteristic on the foresole portion versus the heel portion of that shoe sole. In yet a further customization, the bowler may desire that the friction characteristics of each foresole and heel be adjustable depending on, for example, the surface characteristics of the bowling center in which a particular competition is staged, the day-to-day changes in temperature and humidity in the bowling center, or an increase in confidence as the bowler warms up and reaches peak performance during the course of a match.

One technique for permitting a bowler to adjust the friction characteristics of one or both shoes, even during competition, is disclosed in U.S. Pat. No. 5,542,198. The concept described therein provides for replaceable foresole and heel surface elements of different configurations and performance characteristics. Although this technique has enjoyed some commercial success, it has the disadvantages of requiring a bowler to carry a kit of varying replacement pads and, even with such a variety of pads, each adjustment increment is a step change, without continuous adjustability.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, the effective friction of the shoe is adjusted by changing the angle of a portion of the sole, relative to the shoe centerline. According to another aspect, the wearer's weight distribution on the sole can be similarly adjusted.

In one embodiment, the heel portion of the sole is effectively hinged and an actuating device is spaced from the hinge axis, whereby the wearer can adjust an actuator connected to a drive member that increases or decreases the angle of the hinge. The hinge axis can be perpendicular to the centerline, either in the front of the heel with the drive member embedded in the back of the heel, or in the back of the heel, with the drive member is embedded in the front of the heel.

This angulation has two significant consequences that affect sliding friction. First, the angulation affects the location on the heel, of the first contact of the heel on the floor following the initial sliding of the foot on the foresole. Secondly the hinging affects the total area of the heel that contacts the floor as the bowler shifts more weight into the heel in order to stop, or brake, the slide. Both of these effects can be adjusted without the replacement of any portion of the heel, and without manipulating any exposed region of the heel relative to another exposed region.

Adjustment of the sliding friction characteristics of the foresole is also of significance in bowling shoes. The invention is not limited to adjustment of the heel by a hinging action about an axis perpendicular to the shoe centerline. The foresole can likewise be angulated to adjust the sliding friction characteristics.

More generally, angulation can be effected in the foresole or in the heel, about an axis perpendicular to the shoe centerline, or about an axis that is on or parallel to but offset from the centerline. In this manner, one side of the heel, or one side of the foresole, can be raised or lowered relative to the other side. This kind of lateral adjustment can affect the time dependent friction force resulting from a particular bowler's unique weight transfer in the foot bed during the course of completing the delivery of the bowling ball. As with the heel angulated about an axis perpendicular to the centerline, the lateral adjustment can affect the location of the foresole or heel that first contacts the floor, the total area of the foresole or heel in contact with the floor during the delivery, and the weight distribution over the heel or foresole.

The adjustment device is partially embedded in one or both of the heel or foresole portions of the sole and is preferably accessible as the sole faces the user's hand or tool in the user's hand. Alternatively, especially in embodiments wherein the hinge is in the heel, the adjustment device can be accessed at an upstanding exterior surface of the heel, such as at the back rim. Actuation of the device can be by any means under the control of the end-user of the shoe.

The ability to adjust the angle of the heel or foresole, front to back and side to side, can also provide benefits in other performance characteristics that do not depend significantly on the user's sensitivity to sliding friction, but do depend for comfort or safety, on adjustability of the weight-bearing regions. Unlike the present invention, known comfort adjustment techniques do not rely on a hinging of the weight bearing surface of the heel or foresole in a manner that angulates the exposed weight bearing surface relative to the centerline of the shoe.

In a more detailed characterization of the invention, a shoe having an adjustable weight bearing bottom surface comprises an upper supported by a sole extending generally along a longitudinal centerline, the sole having an arch, a foresole defining a first weight bearing bottom surface longitudinally forward of the arch, and a heel defining a second weight bearing bottom surface longitudinally behind the arch. Each of the first and second weight bearing surfaces has front and back regions and lateral side regions. An adjustment device angulates one of the first or second weight bearing surfaces. Preferably, the adjustment device has a drive member at least partially embedded in the sole and an actuator connected to the drive member such that adjustment of the actuator angulates one of the first or second weight bearing surfaces in relation to the centerline. It should be understood that as used herein, “region” denotes the general location of a sub-area of the outside of a heel or sole, such that, e.g., a side region of the heel can extent into the front or back of the heel.

The invention can be further characterized in a preferred embodiment wherein the sole includes an exterior outsole having the bottom weight bearing surfaces and a midsole between the upper and the outsole. The drive member spans the midsole and outsole. The actuator selectively expands or contracts the drive member to push or pull the outsole away from or toward the midsole at the location where the drive member is embedded.

The adjustment device can take a variety of forms. In one embodiment, one disc is embedded in a base portion of the sole, such as in the midsole, and another disc is embedded in a movable portion of the sole, with a threaded bore for receiving a worm screw or the like that has its drive end accessible at the exterior of the sole. With a screw driving device such as an Allen wrench or the like, the user can readily displace the disc in the movable portion of the sole relative to the stationary disc in the base of the sole, thereby increasing or decreasing the angulation about the hinge axis. This can be implemented for continuous adjustment, or can be ratcheted for repeatable stepwise adjustment.

In another form, the adjustment device can be a disc interposed between the base portion of the sole and the movable portion of the sole, mounted for rotation with an arc of the disc accessible externally for rotation by the user. The disc has variable thickness, preferably monotonically increasing from the minimum to the maximum, whereby rotation of the disc acts a wedge which, depending on the thickness of the disc at the contact with the opposed sole surfaces, defines the hinge angle.

Other adjustment techniques include an adjustable plug, jack or the like that can be pushed or extended through the footbed or mid sole, to angulate the heel or foresole. An air injection pump or other diaphragm or bladder-type member can likewise be used for this purpose. A step jack with bar analogous to one type of common car jack, or a pulled lever type device, could also be adapted for this purpose.

In some embodiments, increasing the angle will produce a gap or separation between the base portion and the angulated, weight-bearing portion of the sole. Preferably, measures should be taken to compensate for this discontinuity and resulting decrease in direct weight bearing surface between the base portion and the movable portion of the sole members. This compensation can take the form of providing robust, wide components for the drive member, such as the discs mentioned above, and assuring that the discs are firmly mounted in the respective seats or other stabilizing foundation within the separable components.

Another advantage uniquely achievable with the present invention is the ability to effectuate a reverse inclination on either the heel or foresole. Bowling, athletic, and other performance shoes, as well as street shoes, are universally manufactured with the main weight bearing, ground contacting surface of the heel in substantially the same plane as the weight bearing, ground contacting surface of the foresole. In other words, the center of the foresole and center of the heel lie flat on a flat surface. As an example with an adjustable heel according to the invention, the neutral adjustment position can correspond to the conventional coplanar relationship between the heel and the foresole, but with positive and negative adjustment options, whereby a back region of the heel weight bearing surface can be raised above ground level, or the front weight bearing region of the heel could be raised above ground level. Similarly, the back region of the heel could be lowered relative to the foresole, or the front region of the heel could be lowered the relative to the foresole. This added capability may be attractive to some bowlers who have unusual foot shapes, approaches, or braking tendencies. When combined with the further option of the exposed surface of the adjustable heel comprising two or more different materials, even greater customization of performance may be achieved.

It should thus be understood that important an aspect of the invention is that the exposed surface of the sole, i.e., one or both of the heel or foresole, is angulated. There is no adjustment of the footbed or other shoe component that conforms to the wearer's foot. The purpose of the angle adjustment is to increase or decrease the surface area of the sole that contacts the ground or floor. The footbed remains in the same relation to the shoe centerline, but the exposed surface of the adjusted sole portion changes its angular relation to the shoe centerline. This adjustment can affect the timing of when certain portions of the sole contact the ground, which of multiple materials contact the ground and in what sequence, and how the weight of the wearer is distributed on various portions of the foresole and heel.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the invention will be described with reference to the accompanying drawing, in which:

FIG. 1 is a schematic longitudinal section view of a shoe incorporating one embodiment of the invention;

FIG. 2A is a schematic detail view of the heel where a representative adjustment device is in a neutral position, FIG. 2B is similar to FIG. 2A, but with the adjustment device in a different configuration, producing an angulation in the heel about a hinge axis at the front of the heel, and FIG. 2C is a view similar to FIG. 2B, but for an alternative embodiment in which the hinge axis is at the back of the heel;

FIG. 3 is a schematic representation of another embodiment of an adjustment device for angulating the heel;

FIG. 4 is a schematic representation of yet another adjustment device for angulating the heel;

FIG. 5 is a schematic representation of an actuation device for angulating the heel about a different axis;

FIG. 6 is an elevation view of the medial heel portion of a left bowling shoe incorporating an embodiment of the invention analogous to that shown of FIG. 1;

FIG. 7 is a bottom plan view of the heel shown in FIG. 6;

FIG. 8 is a section view along line 8-8 of FIG. 7;

FIG. 9 is a section view along line 9-9 of FIG. 7;

FIGS. 10A, B, and C schematically illustrate one of many possible techniques for including a ratchet feature with the adjustment device;

FIG. 11 is a schematic of another embodiment wherein two adjustment devices are situated in the back portion of the heel, on either side of the shoe centerline;

FIG. 12 is a schematic of another embodiment, wherein two adjustment device are situated in the heel, on the same lateral side of the shoe centerline; and

FIG. 13 is a section view of one embodiment for implementing the invention in the foresole of a shoe, with the adjustment device situated laterally of the shoe centerline.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIGS. 1 and 2 show a schematic representation of one embodiment of the invention as implemented in a left bowling shoe. The representative bowling shoe 10, has an upper 12 supported by a sole 14 having a foresole with associated flat slide surface 16 and heel 20 defining a nominally flat brake surface 18. The sole can have one or more layers. An angulation adjustment device 22 is situated in the heel 20 for changing the angle between the surface 18 and the surface 16, thereby changing the area of the heel surface 18 in contact with the, e.g., bowling lane approach, when the foresole is sliding flat on the approach and the bowler transfers weight into the heel to control braking. For purposes of the present description the term “sole” refers to the entire bottom structure of the shoe, which for exemplary purposes, can conveniently comprise a foresole associated with surface 16, a heel associated with surface 18, and an arch (often but not necessarily recessed) situated therebetween.

FIG. 2 shows a representative construction of the heel portion of a shoe incorporating embodiments of the present invention. The sole construction can include insole 26 and outsole 28 as shown in FIG. 2A. Similarly, the heel 20 includes a base portion 30 attached to midsole 26 or extension of outsole component 28, and an active portion 32. The adjustment mechanism or device 22 is partially embedded in the heel, leaving an exposed actuation surface or component 24, and spans the base portion 30 and active portion 32. In this context, “spans” means the device remains in contact with the spanned components. In shoes having a recessed arch, the base portion 30 and active portion 32 of the heel are analogous to the midsole 26 and outsole 28 of the foresole, in that these are the two layers closest to the ground when the shoe is worn.

The effect of manipulating the adjustment mechanism 22 from a nominal condition in FIG. 2A, whereby active heel portion 32 fully abuts the base portion 30, is shown in an exaggerated condition in FIG. 2B, where the active portion 32 pivots about a hinge axis 33 at the front edge or rim of the heel, and has in part separated from the base portion 30 at the back edge or rim. The mechanism 22 has a first disc 34 embedded in the base 30, and a second disc 36 embedded in the active portion 32, with a worm screw 38 fixed at one end 40 to disc 34 and engaging a threaded bore in disc 36. The other end 24 has a slot or socket for rotating the screw.

Upon rotation of the screw, the disc 36 is displaced relative to disc 34, thereby separating active portion 32 from base portion 30, creating a gap 44. This also creates an angle 46 relative to the horizontal (such as a flat floor) 42.

The material at or along hinge or pivot 33 can be glued or sewn relatively tightly, and the interface between the periphery of the base 30 and active portion 32 can be sewn loosely (not shown), especially adjacent the location of gap 44, to assure that the hinging occurs at the desired hinge axis and that the base and active portions are separable but to a limited extent at gap 44. Also, a region (preferably about 50%) of different material than the remainder of the active portion 32 of the heel can be provided to produce a coefficient of friction at exposed surface 18′ on one side of the actuation device 22 that is different from the coefficient of friction on the remainder of the surface 18″.

FIG. 2C shows an alternative in which the hinge axis 33′ is at the back edge of the heel and the gap 44′ opens at the front edge of the heel, whereby the angle 46′ is created between heel surface 18 and the ground 42.

FIG. 3 is a schematic of another embodiment in which wedge disc 48 is shown between heel portions 30 and 32. The disc 48 is situated in the space between (i.e., spans) the base 30 and active portion 32 with the center of the disc having an opening through which shaft 56 passes. The shaft has one end fixed to support member 52, which is in turn fixed within base 30, and another end fixed to support 54, which is fixed within active member 32. The disc has a varying thickness such that, upon rotation by the user, the selected thickness of the disc will bridge the base and active portion 30, 32 thereby define the gap and thus the angle that is established between members 30 and 32. An arc segment of the disc projects from the exterior surface of the heel, preferably at the back, thereby serving as a thumb wheel, which directly angulates the heel. The disc 48 functions as both the actuator and the drive member of the adjustment device.

FIG. 4 depicts another embodiment wherein the adjustment mechanism 58 comprises a thumb wheel 60 that is exposed at the rear of the base portion 30, for the user to rotate screw 64 which in turn advances or retracts a disc or the like 62 embedded in portion 32, along with portion 32.

The same concept can be utilized to change the angle of the active portion 32 relative to horizontal 42, laterally as suggested by arrow 74 in FIG. 5. FIG. 5 is a view from the back of the shoe, in the direction of arrow V as shown in FIG. 1. In this embodiment, the adjustment device is situated adjacent either the medial or lateral exterior surface of the heel, thereby permitting the adjustment of the pronation angle of the heel. Any of the adjustment devices previously described may be utilized for this embodiment. A device 66 analogous that shown in FIG. 2 is shown in FIG. 5. A first disc 68 is embedded in the base portion 30 and a second disc 70 is embedded in active portion 32, with an adjustment screw 72 extending between the discs and exposed to a bottom surface of the heel for access by the user. The active and base portions 32, 30 can be separated or brought closer together, with an effective pivot or hinging axis at 76, running parallel to but offset below the shoe centerline. This raises or lowers one side of the exposed surface of the heel, relative to ground the 42, as shown at 74.

It should thus be understood that the front-to-back angulation represented by α in FIG. 1 and the side-to-side angulation represented by arrow 74 in FIG. 5 can each be considered as changing the relationship of a weight bearing surface to the longitudinal centerline of the shoe or sole

FIGS. 6 through 9 show additional details for implementing a variation of the embodiment shown generally in FIGS. 1 and 2. In this embodiment, the adjustment device is situated in the forward region of the heel, with the hinge axis situated toward the back of the heel, in contrast to the embodiment shown in FIG. 1, where the adjustment device is centered or toward the back of the heel, and the hinge axis is relatively forward in the heel.

FIG. 6 is an elevation view of a bowling shoe 100, rearward of the arch. In this view the adjustable, active portion of the heel is shown at 112, adapted for contacting the ground. The base portion 114 of the heel rests on the active portion 112, and a riser portion 116 of the shoe upper is connected to the base portion 114. In this context, base portion 114 can be considered a midsole component in relation to the active portion 112, which can be considered the outsole component.

FIG. 7 shows the same portion 100 of the shoe depicted in FIG. 6. The adjustment device 118 is situated in the front or forward portion of the heel, substantially vertically beneath the shoe centerline CL. Only the adjustment screw 120 is visible and accessible from the bottom of the heel. The adjustment screw 120 can carry a structural or applied marker for selective alignment with visible discreet indicia 122 carried on the surrounding surface of the heel. In this manner, the user can reproduce a particular angular adjustment by realigning the marker with a particular one of the indicia. Preferably, the adjustment device includes a ratchet or similar discrete action, corresponding to the discreet indicia.

In this embodiment, the adjustable portion 112 and the base portion 114 of the heel converge 124 at the rearward portion of the arch, where a gap is formed which increases or decrease in size according to the position of the adjustment device. At the back of the heel, a fulcrum or pivot line is effectively formed by the overlap of the base 114 relative to the active portion 112, as shown at 126, 128. The overlap 126 serves as a curtain, camouflaging the pivoting and therefore avoiding any detrimental aesthetic appearance in the shoe. Alternatively, an accordion type covering can be provided.

FIG. 8 is a section view through line 8-8 of FIG. 7 and FIG. 9 is a section view through line 9-9 of FIG. 7. The base 114 serves as the mid sole and the adjustable portion 112 serves as the outsole. In this particular embodiment, the risers 116 forming part of the upper are connected to the base 114, such that the inner surface of the riser and the upper surface of the base portion merge to form foot bed 130′, 130″. The side portion of the base 114 can also provide an overlap or curtain 132 relative to the sidewall 134 of the active member 112. The exposed bottom surface of the active member 112 can have recesses or other patterns 136 (not shown in FIG. 7) in a well-known manner, for both aesthetic and functional purposes, but the overall boundary of the bottom surface is substantially flat. Within the active portion 112, one or more cavities 138 can be formed for weight savings and comfort.

In the illustrated embodiment, a substantially circular rim 140 provides a support wall and is upstanding to the extent of close or contact relation with the underside of the base portion 114. A cavity 142 is established within the support wall 140, for containing the main components of the actuating device. In this embodiment, the active disc 144 rests on transverse support surface 146 at the bottom of the support wall 140. This can be cemented in place, or rotationally restrained by lugs or the like (not shown) engaging the support wall 140. Another disc 148 is seated for rotation at 150 at the underside of the base member 114. An Allen screw or the like 120 spans these discs and is fixed with respect to disc 148, but cooperates with the active disc 144 as in a worm gear. In this manner, rotation of the screw forces the active disc 144 to move away from or toward the stationary disc 148. As the active disc 144 separates and moves away from the fixed disc 148, it acts on the support surface 146 to cause separation of the active portion 112 of the heel from the base portion 114 of the heel along interface 152. As a result, much of the weight of the bowler after release of the ball and into the follow-through shifts to the heel and is ultimately transmitted from the fixed disc 148, through screw 120, to the active disc 144. Accordingly, the screw threads and the mating threads in the active disc 144 will be sufficiently robust to accommodate this weight. Furthermore, inasmuch as the heel 112 has separated from the base 114 the weight will not be transmitted to the active portion 112 at the sidewalls through the interface 152. The active disc 144 should be of sufficient width or diameter, or include other stabilizer structure (not shown) to enable the user to maintain proper balance during desired or inadvertent lateral weight shift within the foot bed 130.

As described above, during adjustment, the active portion 112 will separate to some extent form the base portion 114, as a result of the displacement of the active disc 144 relative to the fixed disc 148. While the wearer applies weight on the foot bed 130, these members 112, 114 are urged toward each other. However, during a bowler's stride or at other times when the shoe is above the ground without support from below, the active portion 112 would have a tendency to separate from the base portion 114. This is prevented by the gluing and/or stitching described above with reference to FIG. 2. Alternatively, or in addition, other embodiments of the adjustment device itself can include structure that is fixed with respect to the base 114, such as described below with respect to FIG. 10.

FIGS. 10A, B and C show one embodiment for including a ratchet mechanism or similar step-wise, incremental setting of the degree of adjustment. This is especially helpful in conjunction with the indicia previously described, for precisely returning the adjustment to a known setting that is to be reproduced. The active portion of the heel 112′ includes stationary but rotatable disc 140 with rigidly projecting adjustment screw 142. A ratchet type mechanism 144 is also located in base portion 114′, spring loaded toward to circumference of the disc 140, which has a saw toothed or similar rim 140′. The members 146, 148 are threaded to screw 142 and, as the screw is rotated, the members are displaced along the screw, thereby moving active heel portion 112′ either toward or away from base portion 114′. The ratchet-type or similar detent mechanism retains the screw in a selected rotational position upon completion of the adjustment. Such movement is preferably accompanied by a sequential clicking sound generated between the ratchet 144 and rim 140′.

In a preferred implementation in which a single adjustment device is on the shoe centerline at the back of the heel, the movable disc has a diameter of at least about 50 mm for providing sufficient stability. The ratchet has at least seven stop positions, with eight being ideal, e.g., +4 to 0 (neutral whereby the heel and foresole are substantially coplanar) to −4. Each turn of the screw through 180 degrees, advances the moveable disc and active portion of the heel, about 0.5 mm.

FIG. 11 shows another embodiment 200, in which two actuation devices 202, 204 are situated in the rearward region of the heel, thereby hinging the heel about an axis 206 in the forward portion of the heel, transverse to the centerline.

FIG. 12 discloses another embodiment 300 wherein two actuation devices 302, 304 are both situated on one lateral region of the centerline of the heel in a manner that effectuates a lateral adjustment about a hinge axis at 306 that is parallel to but offset from the shoe centerline.

FIG. 13 shows another embodiment 400, implemented in the foresole along one lateral side of the shoe centerline 402 whereby a lateral adjustment can be made by actuating the adjustment device 404 to angulate the outsole 406 relative to the midsole 408 about a hinge axis 410 that is parallel to but laterally offset from the shoe centerline.

FIG. 13 also shows schematically within the phantom lines 412, that other types of adjustment devices can be located for access through the footbed 414, to angulate not only the foresole, but alternatively the heel, either front to back or laterally.

From the foregoing detailed examples, one of ordinary skill in this field can also implement a hinge adjustment in the foresole about an axis transverse to the centerline, thereby lifting or lowering the forward or back portion of the foresole, in a manner analogous to that described with respect to the heel.

It should be appreciated that the foregoing embodiments can be implemented with only one adjustment device, but two devices enhance stability and offer greater precision, especially for the lateral adjustment. Two or more can be used in combination, for fore/aft and lateral angulation. The invention can be used in other types of performance shoes, including but not limited to shoes used in court games, such as basketball or tennis, and walking shoes, driving shoes, etc.

Claims

1. A shoe having an adjustable weight bearing bottom surface, comprising: an upper supported by a sole extending generally along a longitudinal centerline, said sole having an arch, a foresole defining a first weight bearing bottom surface longitudinally forward of the arch, and a heel defining a second weight bearing bottom surface longitudinally behind the arch, each of said first and second weight bearing surfaces having front and back regions and lateral side regions; and an adjustment device at least partially embedded in the sole for selectively angulating one of said first or second weight bearing bottom surfaces in relation to said centerline.

2. The shoe of claim 1, wherein the adjustment device includes a thumbwheel.

3. The shoe of claim 1, wherein said sole includes an exterior outsole having said bottom weight bearing surfaces and a midsole between the upper and the outsole; said adjustment device spans said mid sole and outsole; and said adjustment device selectively expands or contracts to push or pull the outsole away from or toward the midsole.

4. The shoe of claim 3, wherein said first or second weight bearing surface angulates about an axis on one side of the adjustment device, thereby forming a gap between the sole and midsole on the other side of the adjustment device; and a curtain is provided over said gap between the sole and the midsole.

5. The shoe of claim 1, wherein said sole includes an exterior outsole having said bottom weight bearing surfaces and a midsole between the upper and the outsole; the outsole and midsole are partially affixed to each other, leaving a gap therebetween and establishing a hinge axis; and said adjustment device comprises a disc of varying thickness that spans said gap and is rotatable to selectively angulate the outsole relative to the mid sole.

6. The shoe of claim 1, wherein the adjustment device is in the heel; the weight bearing surface of the heel is in one position, substantially flat and coplanar with the weight bearing surface of the foresole; the heel angulates to other positions about an axis that is perpendicular to the shoe centerline; and the adjustment device has an adjustment ranging in both positive and negative angles for the other positions, relative to said plane.

7. The shoe of claim 1, wherein said adjustment device has a drive member at least partially embedded in the sole and an actuator connected to the drive member such that adjustment of said actuator angulates one of said first or second weight bearing surfaces in relation to said centerline.

8. The shoe of claim 1 wherein said adjustment device has a drive member at least partially embedded in the sole and an actuator connected to the drive member and accessible when the shoe is held in one hand, such that manual adjustment of said actuator angulates one of said first or second weight bearing surfaces in relation to said centerline.

9. The shoe of claim 8, wherein the angulation is about an axis that is perpendicular to the centerline.

10. The shoe of claim 9, wherein the angulation axis is in the front of the heel and the drive member is embedded in the back of the heel, such that said adjustment raises or lowers the back of the heel relative to the front of the heel.

11. The shoe of claim 9, wherein the angulation axis is in the back of the heel and the drive member is embedded in the front of the heel, such that said adjustment raises of lowers the front of the heel relative to the back of the heel.

12. The shoe of claim 8, wherein the angulation is in a direction around the centerline.

13. The shoe of claim 12, wherein the drive member is embedded in the heel laterally of the centerline such that said adjustment raises or lowers one side of the heel relative to the other side of the heel.

14. The shoe of claim 12, wherein the drive member is embedded in the foresole laterally of the centerline such that said adjustment raises or lowers one side of the foresole relative to the other side of the foresole.

15. The shoe of claim 8, wherein said sole includes an exterior outsole having said bottom weight bearing surfaces and a midsole between the upper and the outsole; said drive member spans said mid sole and outsole; and said actuator selectively expands or contracts said drive member to push or pull the outsole away from or toward the midsole at the location where the drive member is imbedded.

16. The shoe of claim 8, wherein the actuator is a worm screw.

17. The shoe of claim 16, wherein the sole has an active portion defining said weight bearing surface and a base portion between the active portion and the footbed; the worm screw has one end accessible at the weight bearing surface for receiving an adjustment tool and another end connected to a stationary disc bearing on the base portion; and a movable member is supported in the active portion and threaded to the screw between the ends; whereby rotation of the screw displaces the movable member along the screw, thereby displacing the active member commensurately.

18. The shoe of claim 16, wherein a ratchet is operatively associated with the screw, for retaining the screw in a selected rotational position upon completion of the adjustment.

19. The shoe of claim 16, wherein indicia are associated with the driven end of the worm screw and uniquely correlated to the rotational position of the screw.

20. The shoe of claim 8, wherein indicia are associated with the actuator and uniquely correlated to the position of the drive member.

21. The shoe of claim 1, wherein at least one of the first and second weight bearing surfaces, for contacting the ground or a floor, comprises a plurality of materials that are present in predefined surface areas; and the adjustment of the angulation changes the proportion of each material that contacts the ground or floor.

22. The shoe of claim 21, wherein the shoe is a bowling shoe.

23. The shoe of claim 1, wherein the shoe is a bowling shoe.

24. The shoe of claim 1, wherein the shoe is a driving shoe.

25. The shoe of claim 1, wherein the shoe is a court game shoe.

26. In a bowling shoe having a substantially flat foresole and a substantially flat heel in substantially coplanar relation to the foresole for contacting a floor, the improvement comprising an adjustment device in the heel for angling the heel out of said substantially coplanar relation with the foresole.

27. The bowling shoe of claim 26, wherein the heel has front and back regions, and the angling hinges the front or back region of the heel relative to the back or front region of the heel, respectively.

28. The bowling shoe of claim 27, wherein the adjustment device has a neutral position in which the heel and foresole are substantially coplanar, and a range of adjustment about the neutral position including raising the front region relative to the back region and lowering the front region relative to the back region.

29. The bowling shoe of claim 27, wherein one region has a surface having a first coefficient of friction and the other region has a surface having a different coefficient of friction.

30. The bowling shoe of claim 26, wherein the heel has left and right side regions, and the angling hinges the left or right region of the heel relative to the right or left region of the heel, respectively.

31. The bowling shoe of claim 26, wherein the heel has a heel base in fixed relation to the footbed of the shoe and the underside overlying a movable heel outsole that contacts the floor in use; the heel outsole has an internal cavity defined by an upstanding support wall extending from a transverse support surface up to close or contact relation with the underside of the heel base; an active disc is fixed to the transverse support; a passive disc is seated in fixed position for rotation at the underside of the heel base; a worm screw spans the discs, fixed to the passive disc and threaded through the active disc; an actuating end of the worm screw penetrates the transverse support surface for accessibility externally of the heel outsole; whereby external rotation of the screw forces the active disc to move away from or toward the passive disc such that as the active disc and moves toward or away from the passive disc the heel outsole is displaced relative to the heel base to angle the heel outsole out of coplanar relation with the shoe foresole.