Note: Descriptions are shown in the official language in which they were submitted.
The present invention relates to boots, and
more particularly, to boots used in the mining industry.
- Boots used by miners are traditionally made of
rubber and are heavily reinforced by hard rubber caps
and ribs. An average pair of boots presently used in
the mining industry weighs approximately 8 lbs.
- Boots for underground mining are usually supplied
in two types, that is, a first type of a relatively light `
ruhber material having a hard rubber toe cap, and rela-
tively form-fitting ankle and calf portions with the
front of the boot being partially laced from the top.
The other type of boot includes a heavier rubber on
canvas construction having a hard rubber toe cap and a
hard rubber metatarsal guard as well as thick rubber
ribs over the guard and the toe cap. The lighter ~oot is
comfortable and of thin flexible rubber, but can be
utilized only by supervisory personnel underground,
engineers and surveyors, trolley and truck operators,
and underground maintenance personnel. They are unsafe
; 20 and impractical to wear on any mining job that requires
heavy manual work. It is important that personnel doing
such jobs, that is, so-called miners, wear boots which
are built up to sustain heavy wear conditions, that is,
` working and walking on freshly broken rock, with each
piece of rock presenting sharp angles. It is also
important that sufficient protection be provided to
protect the metatarsal portion of the foot as well as
the toes. There is always a danger of tumbling rocks
of varying sizes or heavy equipment landing on that
.,
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portion of the boot.
However, to date, the classical miner's boot
appears to be a remnant of the equipment used by armor-
clad knights in the Middle Ages, giving some protection
to the foot but no flexibility of movement.
The mining boot referred to above and as
somewhat illustrated in U. S. Patent 1,717,127,~ J. Toole,
1929, includes a heavily armored toe and metatarsal guard
portion made up of steel and rubber in a rigid foot
portion. In other words, there is no flexibility between
the toe guard and metatarsal guard portion of the boot~
On the other hand, any normal footwear requires the
greatest amount of flexibility at this very area because
of the hinging action of the toes relative to the remainder
of the foot, in a normal walking attitude.
There have been some suggested improvements in
so-called rubber boots provided wit;h toe guard and meta-
tarsal guards. For instance, U. S. Patent 3,308,560,
J. P. Jones, 1967, describes a rubber boot having a
metatarsal and instep guard integral with the outer sole
of the boot and overlapping with the trailing edge of a
box toeO Slight gaps are left between the laminated
liner and outer to allow for shifting movement between
the metatarsal guard portion and the box toe. However,
although this patent recognizes the problem, it does
little to solve it since the flexing of the metatarsal
guard relative to the box toe would only enhance the
delamination of the laminated layers between which the
guard and box toe are located.
3~ It is an aim of the present invention to provide
an improved mining boot which will have sufficient armor
but which will be lighter and considerably more ~lexible
than an equivalent mining boot.
It ls a further aim of the present invention
to provide an improved heel construction whereby the
heel portion of the boot will collapse when subjected to
severe shock, thereby reducing the probability of injury -
to the heel of the wearer.
Another aim of the present invention is to
provide a one-piece molded boot which is simpler in
construction and requires fewer manual steps and thus
is less costly to produce.
A construction in accordance with the present
invention comprises a safety waterproof boot of molded
plastics material having an integral sole and upper,
the upper including a toe portion and a metatarsal
portion,ap~ote-ctive plate provided in the sole portion
and extending the width and length thereof and allowing
for longitudinal flexing of the sole, a box-shaped rigid
toe guard provided in the toe portion, a rigid arched
metatarsal guard member extending laterally and having
side portions connected to the sole plate, the trailing
edge of the toe guard being spaced inwardly relative
to the leading edge of the metatarsal guard and the
molded plastics material extending between the metatarsal
guard and the toe guard having a flexible hinge portion
in the form of a reverse ~old such that the trailing
edge of the toe guard will pivot inwardly of the leading
edge of the metatarsal guard when the toe portion of
the boot is being pivoted relative to the boot.
In a more specific embodiment of the present
invention, the metatarsal guard includes a pair of
opposed flanges at the edges of the side members and
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fixed to the underside of the sole plate while the
toe guard member includes inwardly extending flanges
lying over the top surface of the sole plate. The
heel includes a portion of the sole plate extending
therewithint and a plurality of recesses formed therein
providing narrow walls of plastics material therebetween
such that the walls can collapse in the case of a
severe shoc~ applied to the heel.
Having thus generally described the nature of
the invention, reference will now be made to the accom-
panying drawings, showing by way of illustration, a
preferred embodiment thereof, and in which:
Figure 1 is a side elevation of a mining boot
in accordance with the present
invention, ~,
Figure 2 is a fragmentary horizontal cross-
section taken along line 2-2 of
Figure 1,
Figure 3 is a fragmentary vertical longitudinal
cross-section of the boot shown in
Figure 1, and
Figure 4 is a plan view showing partly in
cross-section a side wall of the
boot and partly the metal guard
members and sole plate of the boot.
Referring now to the drawings, a mining boot
10 is shown having a sole 12, heel 14, toe portion 16,
a metatarsal portion 17, and an upper calf portion 15.
The boot is made from plastics material P
and can be injected in one piece. In the course of
5~
injection moLding the boot 10, the sole 12, heel 14 and
upper are integrally molded. The boot 10, as shown,
includes a metallic sole plate 18 extending the length
and width of the sole 12 and embedded therein. ~he
sole plate 18 has a stepped portion extending into the
heel 14, as shown in Figure 3. A plan view of the sole
piate 18 is illustrated in Figure 4.
A separate metallic toe guard 22 is dome- ;
shaped and includes flanges 28 extending inwardly. It
is fixed such that the flanges 28 overlie the top
surface of the sole plate 18~ It is preferable that
the toe guard not be fixed to the sole plate in order
to allow easy separation in the case of an emergency.
A metatarsal guard 20, which is also of rigid
metallic material such as steel, includes inwardly
extending flanges 30 which are fixed to the sole plate
from the undersurface thereof. In other words, flanges
30 can be welded to the underside of the sole plate 18
allowing for free flexing movement. The toe guard 22
and metatarsal guard 20 are arranged such that the
trailing edge 22a of the toe guard 22 and the leadlng
edge 20a of the metatarsal guard 20 are in the same
laterally extending plane, but the trailing edge 22a
is spaced inwardly on all sides and the top from the
leading edge 20a. A slight space is left between the
toe guard 22 and the metatarsal guard 20 in the area of
the sole plate 18 so as to allow flexing of the sole
plate 18 so that the toe 16 can pivot relative to the
boot. The metatarsal guard 20 has forrned therein a
pair of ribs 23 extending parallel to the laterally
extending plane so as to reinforce the guard 20.
While injection molding of the boot, a last
(not shown~ is inserted in the mold after the armor
structure, including the sole plate 18, toe guard 22
and metatarsal guard 20, have been placed in the mold.
m e last may have a hydraulic extending toe portion
and will include a forwardly extending flange portion
to form the recess 34 about the trailing edge of the
toe guard 22a, as will be described later. The last
Will al60 have frusto-conical projections in order to
form the conical recesses 40 in the heel 14. The
plastics material P is injected into the mold in the
conventional manner, and after the material has cooled
down, the last is removed from the inner portion of the
boot after re~tracting the toe portion.
The so-formed boot includes, as shown in
Figure 3, a hinge flexure area 32 which is in the form
o~ a reverse fold although the bight o~ the fold is
connected directly to the material forming the toe por-
tion 16. In any case, the so-formed, axially extending
recess 34 allows the trailing edge 22a of the toe 22 to
move inwardly with reasonable ease during a walking
attitude when the boot is rocked on its sole as in the
case of a walking shoe. The trailing edge 22a, which
is not overlapped by the trailing edge 20a, will assume
a position wherein the leading edge 22a will overlap
the trailing edge 22a momentarily in the pivoting of
the toe 16 relative to the boot.
The flanges 28 of the toe guard 22 and the
flanges 30 of the metatarsal guard 20 are arranged as
shown in order to provide increased flexing mobility
of the sole plate 18.
The sole 12 of the boot is provided with ribs
24 spaced apart forming grooves. However, in the area
of flexur~ of the sole 12, a larger yroove 26 is
provided to allow for easier flexing of the boot and
also to provide a convenient, rung-engaging foot hold
for climbing ladders.
The heel portion 14 of the boot 10 is molded
integrally with the boot, and in the present embodiment,
is provided with frusto-conical apertures extending
downwardly in the heel forming narrow walls between the
recesses 40 such that in the case of a severe ~hock,
the walls forming recesses 40 will collapse, thereby
acting as a shock absorber for the heel. It might
happen in a mining situation where a miner may accidentally
fall and land on his feet or have to jump from a relatively
high perch onto a rock surface. In such a case, it is
believed that the walls between the recesses 40 will
give, thereby acting as a shock absorber.
The sole plate 18, of course, acts, in addition
to locating the toe guard 22 and the metatarsal guard
20, as armor against sharp objects from beneath the sole.
In order to provide increased ease in the
walking attitude, corrugated ribs 36 are formed in the
ankle area of the boot to allow flexing of the calf
portion 15 relative to the tarsal portion of the boot.
~imilarly, corrugated ribs 38 will be provided
extending vertically in the Achilles tendon area of the
- boot. This particular area of the boot is form fitting
and resiliently presses against the Achilles tendon.
However, when the boot is being placed on one's foot,
the heel of the foot displaces and expands the portion
o
of the boot formed by the corrugations 38, thus enabling
the bo~t to be easily fitted.
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