[0001] The present invention relates to an athletic shoe with a flexible sole.
[0002] During running or jogging it is important that the shoe provide adequate traction
with the running surface. Traction is usually provided by cleats and the like on the
bottom of the sole. In addition, by making the cleats resilient the necessary cushioning
effect is provided for running on hard surfaces. However, in making the cleats resilient,
wear frequently becomes a factor when running on such hard surfaces. While cleats
provide the necessary traction and cushioning, such construction also limits the amount
of surface in contact with the running surface which leads to greater wear.
[0003] Usually wear can be reduced by either increasing the amount of sole material touching
the running surface or by making the sole of a more wear-resistant material. Most
wear-resistant materials which can be economically adapted for use on athletic shoes
are less resilient, thereby reducing the cushioning effect. This leaves the increasing
of the material in contact with the running surface to counteract wear.
[0004] During running there are three stages of foot contact with the running surface. These
stages are heel contact, mid- stance and toe contact or pushoff. Especially between
mid- stance and pushoff, the foot must bend so that finally just the toe is in contact
with the running surface. An increase in the amount of material touching the running
surface usually dictates that the sole and shoe are less flexible. Naturally, any
loss in flexibility hinders the bending of the foot and therefore the running efficiency
of the wearer.
[0005] The present invention provides as a remedy an athletic shoe which provides for greater
surface contact between the sole and the running surface while increasing the traction
with the running surface. Such achievements are further made while improving the flexibility
of the sole so that proper bending of the foot can occur during running and walking.
[0006] In particular, the invention provides an athletic shoe having an upper portion formed
to contain the foot of the wearer with a sole fixed to the upper portion for contacting
the ground. The sole includes a tread formed of bars with valleys therebetween extending
along the direction of the bend lines of the foot so as to provide traction while
improving the bending qualities of the shoe.
[0007] One way of carrying out the invention is described in detail below with reference
to drawings which illustrate only one specific embodiment, in which:-
Fig. 1 is a side view of an athletic shoe in accordance with the invention;
Fig. 2 is a top view of a human foot showing the approximate bend lines thereof in
dotted outline;
Fig: 3 is a bottom view of the shoe of Fig. 1,
Fig. 4 is an enlarged perspective view of a section of the sole of Fig. 3; I
Fig. 5 shows the shoe bending in the manner necessary for running; and
Fig. 6 is a cross-sectional view along the line 6-6 of Fig. 3.
[0008] As shown primarily in.Fig. 1, the invention is embodied in an athletic shoe 15 comprising
an upper portion 16 formed to enclose the foot of the wearer. The shoe is of a normal
configuration with the upper portion being formed of leather or nylon and being adapted
for lacing by shoestrings (not shown) passed through eyelets 17. The upper portion
includes a toe portion 18, a center or shank portion 19 and a heel portion 20. A pliable
cushioning pad 21 having an upper surface fixed to the bottom of the upper portion
provides a wearing or bottom surface 22 for contact with the ground. The upper shoe
portion also includes a heel counter 23 formed to enclose and support the heel. The
sole usually is fixed to the upper portion by gluing or sewing to complete the shoe.
[0009] The shoe is shown in Fig. 5 during the pushoff stage of running with just the forward
portion in contact with the ground or running surface 25. This stage of running requires
the toe and forward portion of the foot to bend at an angle relative to the rest of
the foot. Fig. 2 is a top view of foot comprising toes 26, heel 27 and a center portion
28. As can be seen by the dotted lines 29, 30 and 31, the forward portion of the foot
generally bends along parallel joints which extend at an angle other than normal to
a longitudinal axis 32 of the foot. The bending lines of the foot generally extend
at an angle A of approximately 15° from a line 34 normal to the longitudinal axis
of the foot. Thus, the normal lines of bending of the foot extend generally 15° from
perpendicular to the longitudinal axis of the foot.
[0010] It is the purpose of the present invention to provide a tread which not only will
provide a greater wearing surface area in comparison to soles having cleats but will
also provide improved traction and bending qualities to assist the runner. Accordingly,
as shown in Figs. 1 and 3, the sole 22 is provided with a series of bar treads 35
separated by valley areas 36. The bar treads 35 and the valley areas 36 extend at
an angle relative to the longitudinal axis of the foot roughly corresponding to the
foot bending lines shown in Fig. 2. Preferably, the bar treads have a rearward facing
planar wall 37 and a downward facing planar wear surface 38 for contacting the running
surface. The front wall 39 of the bar tread in the embodiment shown is of a stepped
or serrated configuration formed of steps 39A extending from the valley area 36 between
the bar treads.
[0011] In practice, the rearward facing wall 37 of the bar treads provides gripping engagement
with the running surface during running and acceleration. When the foot is set down
on the running surface the sloping front surface 39 provides somewhat of a cushioning
effect allowing the bar tread to roll rearward slightly for providing a resilient
body to cushion the shock. As shown in Fig. 3, the bar treads extend along the sole
below the toe and the mid- portions of the shoe. Under the heel there are located
a series of pads 40, 41, 42, 44, 45 and 46 to provide a firm wear surface under the
outer edge of the foot where most contact occurs as the heel is set down during running.
These pads are of the same approximate thickness as the bar treads. Additional bar
members 47, 48, 49, 50 and 51 are positioned on the bottom of the sole at the inner
heel area. Less wearing takes place in this inner area; therefore, the pads are positioned
further apart to lighten the'weight of the shoe, yet provide sufficient cushioning
and wearing surface. Pads are utilized under the heel to accommodate any slight bending
of the heel portion of the shoe.
[0012] Thus, it can be seen that the invention provides a shoe tread which has a greater
wearing surface provided by the planar surfaces 38 than a cleated shoe, yet facilitates
the bending of the shoe and foot. In addition, improved traction is provided because
of the increased area of the rearward facing walls 37 on the tread for gripping the
running surface. The tread also is easier to keep clean than cleated shoes because
foreign matter can be removed from the valley areas.of the sole. Of course, the tread
members can be of various configurations and cross-sections so long as they are extended
substantially along the bend lines of the foot.
1. An athletic shoe (15), comprising
a shoe upper portion (16) having heel (20)., shank (19) and toe areas (18) in that
order for enclosing the wearer's foot (28);
a sole attached to said shoe upper portion (16) for supporting the wearer's foot on
a running surface,
characterized by:
a cushioning pad (21) of pliable material and having upper and bottom surfaces (22)
with the upper surface fixed to the shoe upper portion (16) and having a longitudinal
axis and longitudinal edges extending along the length of the shoe upper portion (16);
and
a plurality of bar treads (35) fixed to the bottom surface (22) of the cushioning
pad (21) adjacent the toe (18) and shank areas (19) and positioned to extend substantially
from one longitudinal edge thereof to the other.
2. An athletic shoe as claimed in Claim 1, wherein said bar treads (35) are spaced
apart to form valleys (36) therebetween extending from one longitudinal edge of the
cushioning pad (21) to the other edge.
3. An athletic shoe as claimed in Claim 2, wherein said bar treads (35) are neither
parallel nor perpendicular to the longitudinal edges of the cushioning pad (21).
4. An athletic shoe as claimed in Claim 3, wherein said bar treads (35) and valleys
(36) are positioned parallel to each other.
5. An athletic shoe as claimed in Claim 4, wherein said bar treads (35) extend at
an angle of approximately fifteen degrees to a line extending normal to the longitudinal
axis of the cushioning pad (21) and extend generally parallel to the normal bend lines
(29, 30, 34) of the wearer's foot (28).
6. An athletic shoe as claimed in Claim 4, comprising raised pads (40-46; 47-51) of
approximately the same thickness as the bar treads (35) and fixed in spaced relationship
to each other to the bottom surface of the cushioning pad (21) adjacent the heel portion
(20) of the shoe (15).
7. An athletic shoe as claimed in Claim 6, wherein pads (40-46) are positioned closer
together adjacent one of the longitudinal edges of the cushioning pad (21) than pads
(47-51) adjacent the other longitudinal edge.