[0001] This invention relates generally to a shoe insert and more specifically to a shoe
insert for the heel of the shoe which acts as a heel shock absorber.
[0002] Numerous shoe inserts have been proposed and are on the market today. These inserts
range from a general type of soft cushioning material as well as to inserts which
seek to establish air circulation within the shoe, and to inserts which are designed
to reduce foot odour. In all cases of which I am aware, these inserts are designed
for purposes such as the above and are not designed so as to act as shock absorbers
relative to the effect of foot impact on the ground during walking, jogging or running.
It is well known that, in the normal walking gait, the heel of a shoe worn by a walker
strikes the ground first and causes an impact on the heel of the person wearing the
shoe. This can be uncomfortable and in some cases highly undesirable if the person
is suffering from any foot, ankle or leg ailments.
[0003] Accordingly, this invention seeks to provide a shoe insert which acts as a heel shock
absorber.
[0004] The features which define a heel shock absorber in accordance with this invention
are set out in the following claim 1.
[0005] Desirably the heel shock absorber easily fits as a shoe insert within the heel end
of the users shoe and geometrically conforms to the heel end of the shoe so as to
provide a substantially snug fit within the shoe.
[0006] Preferably the shoe insert which acts as a heel shock absorber has an upper surface
with its surrounding wall which substantially confirms to the shape of the heel of
the person wearing the shoe.
[0007] Suitably the material from which the shock absorber insert is made is flexible while
providing substantial protection against wear.
[0008] The invention will now be further described, by way of example with reference to
the accompanying drawing, in which:-
Figure 1- is a perspective view of one embodiment of heel shock absorber according
to the present invention;
Figure 2 is a plan from above of the shock absorber of Figure 1;
Figure 3 is a sectional view taken along the lines 3-3 of Figure 2; and
Figure 4 is a sectional view taken along the lines 4-4 of Figure 2.
[0009] There is shown in the drawing a heel shock absorber 11 which is adapted for insertion
into a shoe shown partially in chain lines in Figure 4. The shock absorber includes
a base 13 having an upper face 15 and a lower face 17. Additionally, there is provided
a shallow heel recess 19 in the upper face 15.
[0010] A wall 21 extends upwardly from the base 13 to a predetermined height of an upper
edge 23 at its rear end. The upper edges 24 of the sides of the wall 21 taper downwardly
from the edge 23 at the rear end of the absorber 11 to a front edge 25 of the base
13. The thickness of the wall 21 diminishes from the vicinity of the surface 15 to
the respective edges 23, 24.
[0011] The shock absorber 11 is an insert made'of flexible material of a consistency such
that it will have good wearing characteristics and will also be firm enough to maintain
its configuration in use. The material is preferably a plastics material having a
specific gravity between 0.8 and 1.2 and a durometer hardness of between 36 and 50.
One such material which is available in the USA is known by the trademark Kraton 5152
owned by Shell Chemical. This particular material has a specific gravity of 1.00 and
a durometer hardness of 46. In the preferred embodiment illustrated, the entire shock
absorber 11 is moulded in one piece so as to be integral throughout.
[0012] In order to use the material described above in a configuration which will provide
the desired shock absorbing characteristics, a plurality of substantially open parallel
channels 27 extend laterally across the width of the base 13 and are spaced apart
along its longitudinal axis, being separated by partitions 30. It is preferred that
the channels are designed such that the upper portion of each partition 30 is wider
than its central portion. This configuration allows for flexibility of the partitions
30 between the channels so as to give the necessary shock absorbing effect. One reason
that it is preferred that the upper part of each partition is wider than its central
part is that this shaping of the channels at least reduces and at best prevents any
sensation on the heel of the existence of the partitions.
[0013] As is more clearly shown in Figure 4, the thickness between the faces 15 and 17 remains
substantially constant from a portion adjacent the rear heel area to a portion well
forward thereof until, at the forward end thereof, the width of the base diminishes
as the forward portion tapers (at an angle cf as indicated) to the front edge 25.
This downwardly sloping region is indicated at 35 in Figure 4 and it will be noted
that the frontmost channel (27') also narrows slightly to confirm to the sloping surface
35.
[0014] As is clear from the drawing, the wall 21 maintains the predetermined height of the
edge 23 around the rear part of the heel and then tapers downwardly along the edges
24 to the point at which the base thickness begins to diminish. The angle of this
taper is designated a in Figure 4.
[0015] Referring particularly to Figure 3, it can be seen that the shock absorber is designed
so as to include an arcuate area 31 between the base 13 and the wall 21 so as to more
confortably conform to the sides and rear of the heel of the person who is using the
shock absorber. This configuration is generally carried forward for the entire length
of the wall 21 although the radius of curvature of the arcuate area reduces the closer
it is to the forward end of the absorber 11.
[0016] In order to ensure that the absorber insert 11 remains in place in the heel end region
of the shoe, gripping means 33 are provided which depend from the lower face 17 of
the base 13. In the particular configuration illustrated, the gripping means takes
the form of a plurality of pegs. Since the pegs are of the same material as the rest
of the shock absorber, they provide flexibility while still providing the desired
gripping feature.
[0017] While not limiting the invention in any way, a satisfactory construction for a shock
absorber heel insert includes the following dimensions.

[0018] It is to be understood that shock absorbers according to the present invention will
normally be made in varying sizes (such as small, medium and large) so as to fit properly
in the different sizes of shoes available. The present invention has been proven to
provide extremely noticeable comfort and relief from the shock normally accompanying
the impact of the heel during a walking motion. By relieving this shock, the entire
foot, ankle and the leg are benefited.
[0019] The above description and drawing are illustrative only and are not intended to limit
the invention, the scope of which is to be determnined by the following claims.
1. A heel shock absorber (11) for insertion within a shoe comprising a base (13) having
upper (15) and lower (17) faces and substantially geometrically conforming to the
heel end of said shoe, characterised in that said base (13) has a predetermined thickness
extending along a major portion of the longitudinal axis thereof with said upper face
(15) tapering downwardly at the forward end (25) thereof, in that a wall (21) extends
above said upper face (15) at the outer periphery thereof, said wall (21) having a
predetermined thickness adjacent said upper face (15) and diminishing in thickness
as the height of said wall (21) increases, said wall having an upper edge (23) at
a predetermined height above the rear end of said base (13) and side edges (24) tapering
downwardly towards said forward end (25); and in that a plurality of substantially
open parallel channels (27) are provided in said base, each said channel (27) extending
laterally across the width of said base (13) and being separated from adjacent channels
(27) by a partition (30).
2. A heel shock absorber as claimed in claim 1, characterised in that said base (13)
and wall (21) are integrally formed from a mass of flexible material.
3. A shock absorber as claimed in claim 1 or claim 2, characterised in that the material
from which the absorber (11) is made has a specific gravity between 0.8 and 1.2.
4. A shock absorber as claimed in any preceding claim, characterised in that the material
from which the absorber (11) is made has a durometric hardness between 36 and 50.
5. A shock absorber as claimed in any preceding claim, characterised in that the wall
(21) thereof has an arcuate inner face (31) so as to substantially conform to the
shape of the heel of the user.
6. A shock absorber as claimed in any preceding claim, characterised in that a heel
recess (19) is provided in a rear portion of said upper face (15).
7. A shock absorber as claimed in any preceding claim, characterised in that the major
longitudinal length of said base (13) includes said channels (27).
8. A shock absorber as claimed in any preceding claim, characterised in that gripping
means (33) depend from said lower face (17) of said base (13) to'facilitate holding
of the absorber r11) stationary in a heel region of a shoe.
9. A shock absorber as claimed in claim 8, characterised in that said gripping means
(33) is integral with said base (13).
10. A shock absorber as claimed in claim 9, characterised in that said gripping means
comprises a plurality of pegs (33) subtending from said lower face (17).
11. A shock absorber as claimed in any preceding claim, characterised in that said
partitions (30) have a greater thickness at their upper ends than at the centre thereof.