[0001] The present invention relates to an antistatic shoe.
[0002] Antistatic shoes are currently commercially available which can discharge to the
ground the electrostatic charge accumulated by a person on his body.
[0003] The most common situation is a passenger leaving a car that has just come to a halt.
[0004] If he touches the car body, the passenger can be affected by an electric shock which
is unpleasant although substantially harmless.
[0005] This discharge occurs only if the person is insulated from the ground, for example
by wearing a pair of shoes with a sole made of rubber or other insulating material.
[0006] The need is thus felt of a type of shoe which allows the charge that has accumulated
on the car during motion to discharge to the ground through the body of the traveler
without the traveler being aware of anything or being affected in any way by the event.
[0007] Current antistatic shoes offer an undeniable solution to this problem, although they
suffer drawbacks which are described hereinafter.
[0008] First of all, the technique and the method for producing the antistatic shoes entail
a lot of work and accordingly also affect manufacturing costs.
[0009] A conventional antistatic shoe is in fact constituted by a small coil of conducting
metal wires, for example made of copper, which are usually located proximate to the
heel, above the rubber sole.
[0010] Several individual wires extend from the coil, each wire being arranged in a very
small hole located in a preset region of the sole.
[0011] The wires, by passing through the corresponding holes, reach the lower surface of
the sole, where they are upset.
[0012] In this way, a first electrical bridge through the sole is provided.
[0013] The coil is further electrically connected to a metal tab which passes through a
slot formed in the insole or inner sole inside the upper and ends in an upward region
with a first metallic plate which is arranged horizontally.
[0014] At the metallic plate, proximate to the region of the heel of the overlying insole,
two slots are provided in which two flexible conducting wings are made to slide; the
wings are folded downward and are connected to an overlying second metallic plate.
[0015] In this way the accumulated electric charge can discharge to the ground, by flowing
through the body of the user down to the heel and then through the second metal plate
and the corresponding wings connected to the first metal plate.
[0016] Immediately thereafter, the electric current flows through the tab and the underlying
coil and discharges to the ground by means of the individual wires monolithically
connected to said coil.
[0017] This method for manufacturing antistatic shoes is evidently complicated, leading
to an increase in manufacturing times and costs.
[0018] Moreover, in these conventional antistatic shoes, over time the sole inevitably wears,
and so do the metal wires, and the holes become clogged, often leading to a sharp
decrease in the efficiency of the shoe.
[0019] Other conventional antistatic shoes have different mechanisms for conduction through
the sole, using metallic pins or similar elements, which pass through the insole or
inner sole associated with the upper and reach the lower surface of the sole.
[0020] In some embodiments there is a single grounding point at the heel: this leads to
the drawback of not eliminating the problem when, as often occurs, only the tip of
the shoe is placed on the ground, for example when leaving a car.
[0021] The aim of the present invention is to solve the above-described drawbacks, by providing
a device which allows to obtain a simplified shoe manufacturing process which leads
not only to an economic advantage but also to an improvement in the quality of the
product.
[0022] Within the scope of this aim, an object of the present invention is to provide a
shoe which allows to solve the problem of grounding in the safest and most durable
manner for the user.
[0023] Another object is to provide a shoe whose sole offers maximum uniformity of its components,
without having metallic elements such as nails, pins or coils which can cause discomfort,
especially over time and as the sole deteriorates.
[0024] These and other objects which will become better apparent hereinafter are achieved
by an antistatic shoe according to the present invention, characterized in that it
comprises a sole at which there are provided, in the heel and tip region, connected
seats for at least one insert made of conducting plastics which is connected to the
ground and, by means of a conducting plate, to the insole.
[0025] Further characteristics and advantages of the present invention will become better
apparent from the following detailed description of a particular embodiment thereof,
illustrated only by way of non-limitative example in the accompanying drawings, wherein:
Figure 1 is a partially sectional side view of the upper and of the underlying sole
with an insert, according to the present invention;
Figure 2 is a bottom view of the sole with two protrusions for ground discharge;
Figure 3 is a side view of the upper and of a second embodiment of the sole with the
corresponding insert;
Figure 4 is a bottom view of the second embodiment of the sole with the corresponding
grounding component.
[0026] With reference to the above-cited figures, the reference numeral 1 designates an
upper of a conventional type in which the foot of the user is inserted.
[0027] The reference numeral 2 designates a sole in which at least two through seats 3 and
4 are formed respectively at the tip and at the heel; the seats are connected one
another by means of a channel 5 and are adapted to accommodate a complementarily shaped
insert 6 made of conducting plastic material.
[0028] The insert 6, which is longitudinally elongated, has a central body 7 which is arranged
in the channel 5; two protrusions, designated by the reference numerals 8 and 9, are
provided at the ends of the body 7, are preferably cylindrical or prism-shaped, are
shaped complementarily to the seats 3 and 4, respectively, and are therefore located
at the toe or heel region of the sole or at both regions.
[0029] The insert 6 is kept in place by the mutual thermal bonding of parts of the respective
elements made of plastics.
[0030] A metal plate 10, preferably made of copper, is arranged in a suitable opening 11
formed in the inner sole or insole, designated by the reference numeral 12, which
is arranged inside the upper 1; the lower surface of the metal plate 10 rests on the
underlying protrusion 9 of the insert 6.
[0031] Operation is as follows: with reference to Figure 1, the electrical charge is propagated
through the body of the user down to the heel, which is connected to the insert 6
by means of the metallic plate 10.
[0032] Since the insert has conducting properties, immediate and simple discharge to the
ground occurs when the front protrusion 8 or the rear protrusion 9 makes contact with
the ground.
[0033] It has thus been observed that the present invention has achieved the intended aim
and objects, an antistatic shoe having been provided which is adapted to discharge
to the ground, through the user, the electrostatic charge accumulated for example
by a car during travel.
[0034] Since the insert 6 is made of plastics, walking is optimum, as the insert follows
the deformation of the sole.
[0035] The invention is of course susceptible of numerous modifications and variations,
all of which are within the scope of the same inventive concept.
[0036] Thus, for example, as shown in Figures 3 and 4, it is possible to associate with
an upper 101 a sole 102 which has, in a downward region, a channel 105 which runs
from the toe region to the heel region.
[0037] A complementarily shaped insert 106 made of conducting plastic material is arranged
in the channel 105 and has, in the end adjacent to the heel region, one or more protrusions,
designated by the reference numeral 120, which are directed toward the inner sole
112.
[0038] The protrusions are connected to the upper by means of appropriate complementarily
shaped holes, designated by the reference numeral 121, so as to maintain contact with
a metal plate 110 which is accommodated in a complementarily shaped seat, designated
by the reference numeral 111, which is formed in the inner sole 112 of the upper 101.
[0039] The materials employed, as well as the dimensions that constitute the individual
components of the present invention, may of course be the most pertinent according
to specific requirements.
[0040] The disclosures in Italian Patent Application No. TV99A000096 from which this application
claims priority are incorporated herein by reference.
[0041] Where technical features mentioned in any claim are followed by reference signs,
those reference signs have been included for the sole purpose of increasing the intelligibility
of the claims and accordingly, such reference signs do not have any limiting effect
on the interpretation of each element identified by way of example by such reference
signs.
1. An antistatic shoe, characterized in that it comprises a sole at which there are provided,
in the heel and tip region, connected seats for at least one insert made of conducting
plastics which is connected to the ground and, by means of a conducting plate, to
an insole or inner of the shoe.
2. The shoe according to claim 1, characterized in that said insert is longitudinally
elongated and has a central body which lies in a complementarily shaped channel which
is formed in said sole and connects said seats, at least two lower protrusions being
provided at the ends of said central body and being arranged at said seats.
3. The shoe according to claims 1 and 2, characterized in that said insert associated
with said channel and said seats is kept in place by mutual thermal bonding of parts
of the respective plastic elements.
4. The shoe according to claims 1 and 3, characterized in that it has, in the region
of the heel of said insole or inner sole, an opening which accommodates a complementarily
shaped conducting plate which rests at said underlying conducting insert.
5. The shoe according to one or more of the preceding claims, characterized in that it
has a sole on the lower surface of which there is provided at least one channel which
affects both the tip region and the heel region.
6. The shoe according to claim 5, characterized in that a complementarily shaped insert
made of conducting plastics is arranged in said channel and has, at its end that affects
the heel region, one or more upward protrusions.
7. The shoe according to claim 6, characterized in that said one or more upward protrusions
are connected, by means of suitable shaped holes, to said metal plate accommodated
in a complementarily shaped seat formed in said insole or inner sole.