Golf shoe outsole with bio-mechanically positioned wear bars

BACKGROUND OF THE INVENTION

The present invention relates to shoes, and more particularly to sports shoes having outer soles or outsoles having protrusions to provide increased traction.

Golf shoes are typically comprised of a shoe upper which is attached to some or all of an inner sole, a mid-sole and an outsole. For many years, golf shoes have employed nail-type spikes to increase the traction between the shoe and the grass of the golf course and thereby improve the golfer's footing. These spikes were threaded into sockets carried by a plate mounted on the hidden side of the outsole. Recently, a growing trend has developed away from the use of metal spikes to reduce the incidence of damage to the putting greens.

Initially, golf shoe manufacturers replaced the metal spikes with disc-like, softer spikes composed of a polymeric material, which do less damage to the putting greens. Such soft spikes often utilize the same threaded mounting as did traditional metal spikes, and can be directly substituted in the threaded sockets. New forms of sockets have been developed to accommodate further developments in such soft spikes to improve the traction provided by such spikes and to make it easier and quicker to replace the soft spikes. Some newer golf shoe designs have utilized outsoles having a plurality of integral, pyramid-shaped protrusions instead of spikes. The protrusions are also composed of polymeric material.

The soft spikes and protrusions have reduced the incidence of damage to the putting greens. However, the polymeric material of such soft spikes and protrusions is more susceptible to wear than the metal spikes and must therefore be replaced at more frequent intervals. In an attempt to lengthen the expected lifetime of the soft spikes and protrusions, golf shoe manufacturers have modified the design of the outsoles to include wear bars composed of polymeric material. Such wear bars generally have a rectangular shape and extend downwardly from the surface of the outsole to a support surface which has a much greater surface area than that of the spikes and protrusions. Positioning the wear bars on the outsole is critical to the design of the golf shoe since the wear bars have an adverse effect on traction.

SUMMARY OF THE INVENTION

Briefly stated, the invention in a preferred form is an outsole for a golf shoe which includes a sole member having an outer surface. A plurality of traction enhancing protrusions and a plurality of spikes extend outwardly from the outer surface of the sole member to a ground engagement tip and at least one ground gripping surface, respectively. The outsole also includes a plurality of longitudinally extending wear bars. Each of the wear bars extends outwardly from the outer surface of the sole member to a pair of ground engagement surfaces which are separated by a notch.

The positions of the spikes and wear bars and the orientation of the wear bars are in part determined by bio-mechanical factors determined by the path of the center of pressure and the forces generated during the golfer's swing. In a preferred embodiment, the outsole for a right shoe has three spikes and three wear bars disposed in the lateral area of the sole portion of the sole member, two spikes and four wear bars disposed in the medial area of the sole portion of the sole member, and a single spike and a single wear bar disposed in each of the lateral and medial areas of the heel portion of the sole member. The outsole for the left shoe has three spikes and three wear bars disposed in the lateral area of the sole portion of the sole member, two spikes and five wear bars disposed in the medial area of the sole portion of the sole member, and a single spike and a single wear bar disposed in each of the lateral and medial areas of the heel portion of the sole member. The spikes and the wear bars of the sole portion are longitudinally spaced.

Each of the wear bars has first and second sides and oppositely disposed ends. The first and second sides converge at the ends at an acute angle to define vertically extending end ridges. The notch defines a pair of oppositely disposed dimples in the first and second sides of the wear bar.

It is an object of the invention to provide a new and improved outsole for a golf shoe.

It is also an object of the invention to provide an outsole for a golf shoe having wear bars that provide improved traction with the ground and which reduce the rate of wear of other traction-enhancing elements of the outsole.

Other objects and advantages of the invention will become apparent from the drawings and specification.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention may be better understood and its numerous objects and advantages will become apparent to those skilled in the art by reference to the accompanying drawings in which:

FIG. 1

is a side view of a golf shoe for a right foot, the golf shoe having an outsole in accordance with the present invention;

FIG. 2

is an enlarged bottom view of the shoes of

FIG. 1

;

FIG. 3

is a side view, partly in phantom, of the outsole of

FIG. 2

with the soft spikes removed;

FIG. 4

is a cross-section view, taken along line

4

—

4

, of the outsole of

FIG. 2

;

FIG. 5

is an enlarged cross-section view, taken along line

5

—

5

, of the outsole of

FIG. 2

;

FIG. 6

is an enlarged perspective view of the soft spike;

FIG. 7

is a schematic bottom view of a golfer's left and right shoes illustrating the path of the center of pressure and the direction and relative magnitude of the forces exerted during the golfer's downswing; and

FIG. 8

is an enlarged bottom view of the shoe in accordance with the present invention for a left foot.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the drawings wherein like numerals represent like parts throughout the several figures, a golf shoe outsole in accordance with the present invention is generally designated by the numeral

10

. As shown in

FIG. 1

, an outsole

10

in accordance with the present invention is mounted to an inner sole (not shown) and an upper

12

to form a golf shoe

14

. The outsole

10

includes a sole member

16

defining the sole and heel portions

18

,

20

of the shoe

14

. The shoe upper

12

and the shoe inner sole are well known in the art and may be comprised of any material suitable for use while playing golf. The golf shoe

14

may also include a mid-sole (not shown).

During the golfer's downswing, the center of pressure

22

for the right shoe

24

traverses the sole portion

18

of the shoe

24

from the lateral side

26

to the medial side

28

and the center of pressure

30

for the left shoe

32

moves in a rough figure-

8

shaped pattern extending from the lateral side

26

to the middle of the sole portion

18

, as illustrated in FIG.

7

. Further, the right shoe

24

is subject to pressure which tends to move the shoe

24

forward and the left shoe

32

is subject to pressure which tends to move the shoe

32

rearward, as indicated the pressure vectors

34

,

36

. Should either of the golfer's shoes

24

,

32

slip during his downswing, it is almost certain that the resulting shot will be less than optimal. It should be appreciated that the probability of such slippage is increased when the golf course is damp or wet and when the golf ball is on an uphill or downhill lie.

To reduce the probability of slippage between the golf shoe

14

and the course surface, the outsole

10

further includes a variety of traction-enhancing elements

38

that extend downwardly from the outer surface

40

of the sole member

16

. Such traction-enhancing elements

38

distinguish golf shoes

14

from regular street shoes. The traction-enhancing elements

38

include soft spikes

42

, pyramid-shaped protrusions

44

, and wear bars

46

. All of the traction-enhancing elements

38

are composed of a material which is soft relative to traditional metal spikes, for example polymeric material, to prevent damage to the golf course putting greens. Although the pyramid-shape of the protrusions

44

provides superior traction, the relatively small area of the pyramid tip

48

causes the protrusion

44

to be particularly susceptible to wear. The ground engagement surfaces

50

of the wear bars

46

have a relatively large surface area which is substantially co-planar with the tips

48

of the surrounding protrusions

44

to reduce the rate of wear of the protrusions

44

and thereby extend the life of the golf shoe

14

. In addition, the wear bars

46

help reduce the rate of wear of the soft spikes

42

.

The outsole

10

includes a plurality of receptacles

52

for removably mounting the soft spikes

42

to the outsole

10

. Such mounting means

54

are well known in the art. The receptacles

52

may be integrally formed with the sole member

16

or separately attached.

In one preferred embodiment of the invention, each of the receptacles

52

includes a lip

56

which extends outward from the outsole outer surface

40

. The base

58

of the soft spike

42

is received within the lip

56

such that the lip

56

prevents dirt and moisture from entering the receptacle

52

.

Each of the soft spikes

42

has one or more outwardly extending engagement members

60

for contacting the golf course surface. In the embodiment shown in

FIG. 6

, four engagement members

60

are equidistantly spaced on the outer rim of the soft spike

42

. The outer surface

62

of each engagement member

60

has a relatively large surface area to reduce the wear rate of the spike

42

. Protrusions

64

,

66

extend from the side edges and inner face of each engagement member

60

. The relatively narrow shape of the protrusions

64

,

66

facilitates engagement with the golf course surface to resist lateral movement of the spike

42

relative to the golf course surface.

With reference to

FIGS. 2 and 5

, each of the wear bars

46

has oppositely disposed wedge-shaped end portions

68

,

70

. The sides

72

,

74

of the wear bar

46

meet at an acute angle at the opposite ends

76

,

78

of the wear bar

46

, forming vertically extending end ridges

79

. The end portions

68

,

70

are separated by a notch

80

which extends from the outer surface

50

of the wear bar

46

to a height intermediate the outer surface

40

of the sole member

16

and the outer surface

50

of the wear bar

46

. The notch

80

also forms a pair of oppositely disposed dimples

82

in the sides

72

of the wear bar

46

which extend inwardly toward the axis of the wear bar

46

. The wedge-shape of the end portions

68

,

70

, the end ridges

79

and the notch

80

produce a wear bar

46

that provides better traction between the shoe

14

and the surface of the golf course. However, there is a trade-off for this increased traction. The notch

80

reduces the area of the engagement surface

50

and thereby partially mitigate the wear bar's ability reduce the wear rate of the protrusions

44

and soft spikes

42

.

The positions of the receptacles

52

and wear bars

46

and the orientation of the wear bars

46

are determined by a combination of factors including, the outline or “footprint” of the sole and heel portions

18

,

20

of the golf shoe

14

and bio-mechanical factors determined by the path of the center of pressure

22

,

30

and the forces

34

,

36

generated during the golfer's swing.

With reference to

FIGS. 2 and 8

, there are seven receptacles

52

positioned along the periphery of the outsole

10

of each shoe

24

,

32

. Although there are slight variations, the receptacles

52

of the outsole

10

of the left shoe

32

are positioned in substantially the same locations as the receptacles

52

of the outsole

10

of the right shoe

24

. Five of the receptacles

52

are located in the sole portion

18

of the outsole

10

with three receptacles

84

,

86

,

88

being positioned along the lateral side

26

of the sole portion

18

and two receptacles

90

,

92

being positioned along the medial side

28

of the sole portion

18

. The sole portion receptacles

84

,

86

,

88

,

90

,

92

are longitudinally spaced and the positions of the medial side receptacles

90

,

92

are staggered with respect to the positions of the lateral side receptacles

84

,

86

,

88

with the first medial side receptacle

90

being positioned intermediate the first and second lateral side receptacles

84

,

86

and the second medial side receptacle

92

being positioned intermediate the second and third lateral side receptacles

86

,

88

. The remaining two receptacles

94

,

96

are positioned on the medial and lateral sides

28

,

26

of the heel portion

20

substantially midway between the front and rear ends

98

,

100

of the heel portion

20

.

The outsole

10

of the right shoe

24

has nine wear bars

46

and the outsole

10

of the left shoe

32

has ten wear bars

46

. Eight of the wear bars

102

,

104

,

106

,

108

,

110

,

112

,

114

,

116

on each shoe

24

,

32

are positioned at substantially identical locations. The orientation of six of these wear bars

102

,

104

,

106

,

108

,

110

,

112

are substantially identical while the seventh wear bar

114

of the outsole

10

of the left shoe

32

is rotated approximately 5° counter-clockwise relative to the seventh wear bar

114

of the outsole

10

at the right shoe

24

and the eighth wear bar

116

of the outsole

10

of the left shoe

32

is rotated approximately 80° clockwise relative to the eighth wear bar

116

of the outsole

10

of the right shoe

24

. The ninth wear bar

118

of the outsole

10

of the right shoe

24

is positioned laterally and to the rear of the second lateral receptacle

86

and has a substantially medial-to-lateral orientation. The ninth wear bar

118

of the outsole

10

of the left shoe

32

is positioned medially and to the front of the second lateral receptacle

86

and has a substantially front-to-rear orientation. The tenth wear bar

120

of the outsole

10

of the left shoe

32

is positioned medially and to the front of the second medial receptacle

92

and has a substantially front-to-rear orientation.

While preferred embodiments have been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustration and not limitation.