[0001] The represent invention relates to the technical field concerning footwear production,
with particular reference to the production of strengthening plates for footwear reinforcement.
[0002] In order to give the footwear a greater value, strengthening plates are firmly associated
with the heel insole and can give stronger resistance and high elasticity to this
part of the shoe which supports the loading action performed by the foot and due to
the weight of the body associated thereto.
[0003] The strengthening plates, usually metallic, are obtained by preliminary press molding,
subsequent cutting and heat hardening treatment by tempering and drawing back.
[0004] Figures 1a, 1b show a strengthening plate obtained according to prior art, including
substantially a curved metallic plate 40, with the concavity turned toward the heel
insole, to which it will be associated.
[0005] The plate 40 features a fork-like end 41, which is aimed at being engaged by means
for fastening the heel to the under-the-foot portion of the shoe.
[0006] The strengthening plate features, in its central area, a longitudinal groove 42,
which gives it more strength and high resistance to bending.
[0007] Likewise, the prongs (41a,41b) of the fork 41 usually feature additional grooves
42a, extending longitudinally, and increasing the prongs resistance to bending.
[0008] As it has been clearly shown in Figure 1a, two holes (43a,43b) are made at the extremities
of the longitudinal groove 42, substantially aligned therewith and situated.
[0009] As shown in Figure 1b, the hole 43b in the areas of the strengthening plate fork-like
extremity 41, is situated between the groove 42 and the fork 41.
[0010] According to widely known techniques, the strengthening plate can be fastened to
the heel insole in two different ways.
[0011] According to a first fastening way, additional coupling means are used, such as buttons
and/or pins, which are anchored to the heel insole and engage the above mentioned
holes 43a, 43b, thus obtaining a mutual snap fastening of the strengthening plate
to the heel insole.
[0012] According to a second fastening way, the above mentioned holes 43a, 43b are obtained
by punching, so as to define an winner toothed crown, turned toward the heel insole
and allowing the mutual fastening of the heel insole and strengthening plate.
[0013] In both techniques of fastening of the strengthening plate to the heel insole, the
resistance characteristics of the strengthening plate along a pre-established axial
extension D1 of the latter, are proportional to the longitudinal extension D2 of the
longitudinal groove 42, and it is limited by the presence of the two fastening holes
(43a,43b).
[0014] It is also to be pointed out that the presence of the hole 43b in the area between
the fork 41 groove and the relative extremity of the longitudinal groove 42, considerably
weakens the strengthening plate, increasing the probability of undesired breaking,
which is difficult to foresee.
[0015] In order to reduce the possibility of breaking, it is necessary to increase the distance
of the hole 43b from the inner part of the fork 41, as well as from the extremity
of the groove 42, which results in an undesired reduction of the extension D2 of the
groove 42 and in limiting the strengthening plate mechanical characteristics along
a pre-established axial extension D1 thereof.
[0016] The object of the present invention is to propose a strengthening plate for a shoe,
which avoids the above mentioned drawbacks, assuring a particularly stable coupling
with the, relative heel insoles and, at the same time, best mechanical characteristics,
especially excellent resistance to bending stresses.
[0017] Another object of the present invention is to propose a strengthening plates for
a shoe, which is cheap and which ensures particularly simple and rapid fastening and/or
removal of the heel insole.
[0018] A further object of the present invention is to propose a strengthening plate for
a shoe of high reliability and strength standards in any shoe use condition, without
any change of the shoe functionality.
[0019] The above mentioned, objects are achieved by the features of the independent claim,
while preferred features are defined in the dependent claims.
[0020] The characteristic features of the present invention will be pointed out in the following
description of some preferred embodiments, with reference to the enclosed drawings,
in which:
- Figures 1a, 1b are schematic, respectively lateral and partially section, and top
views of a strengthening plate for a shoe according to the prior art;
- Figures 2a, 2b are schematic corresponding lateral partial section and top views of
a strengthening plate for a shoes proposed by the present invention;
- Figure 3 is a schematic perspective exploded view of the proposed strengthening plate
together with a shoe, in assembled configuration.
[0021] With reference to the above drawings, the reference numeral 1 indicates the proposed
strengthening plate for shoe, substantially formed by a central body C, in which a
longitudinal groove 5 is made for increasing the strengthening plate bending resistance.
[0022] An end A of the central body C forms a fork-like portion 2, defining a pair of prongs
(2a,2b), while the other end B includes means 3 for fastening the strengthening plate
1 to a relative heel insole 10.
[0023] The fork 2 is usually engaged by means for fastening the heel to the under-the-foot
part of the shoe.
[0024] A plurality of small teeth 4, aimed at being fitted in the heel insole 10, are situated
in the inner area 20 of the fork-like portion 2, that is in the area of the inner
edges of the prongs (2a,2b).
[0025] The plurality of teeth 4, each of which extends orthogonal to the fork 2, allows
a mutual fastening of the strengthening plate 1 to the heel insole 10, together with
the coupling means 3.
[0026] Advantageously, the central body C and the relative ends A, B connected thereto,
define a substantially curved plate with the concavity turned toward the heel insole
10.
[0027] The coupling means 3 include preferably a through hole 30, made in the area of the
relative end B.
[0028] The edges 30a of the hole 30 form a toothed crown 31, which is aimed at being fitted
in the heel insole 10 in order to fasten the latter to the strengthening plate 1 (Figure
2a).
[0029] Otherwise, the coupling means 3 can include a peg, fastened to the heel insole 10,
aimed at snap-fitting into the through hole 30, thus keeping the strengthening plate
1 fastened thereto.
[0030] According to a preferred embodiment, the longitudinal groove 5 is substantially symmetrical
with respect to the central body C and substantially aligned with the prongs (2a,2b)
of the fork 2, as well as with the through hole 30 (Figure 2b).
[0031] Like the central body C, each prong (2a, 2b) of the fork 2 features a corresponding
additional groove 50, extending longitudinally thereto (figure 2b).
[0032] According to another embodiment (not shown), the teeth 4 can be made in the outer
area of the fork-like portion 2, that is in the area of the outer edges of the prongs
2a, 2b.
[0033] Independently from the embodiment applied, in relation to the positioning of the
teeth 4 with respect to the fork-like portion 2, and independently from the type of
the coupling means 3 (a peg or toothed crown), the coupling between the proposed strengthening
plate 1 and the corresponding heel insole 10 is obtained by the contemporary action
of the teeth 4 fitted in the heel insole 10 and the above mentioned coupling means
3.
[0034] It is obvious that the proposed strengthening plate 1 for footwear, considering a
pre-established axial extension D1 thereof, ensures better mechanical bending resistance
characteristics with respect to the examples of prior art due to the longitudinally
longer extension D3 (>D2; Figure 1b) of the groove 5.
[0035] Moreover, the proposed solution eliminates almost completely weakened sections, which
could jeopardize the strengthening plate force, like for instance making holes in
the area comprised between the longitudinal groove and the fork, according to prior
art (Figure 1b).
[0036] In the area of the fork-like end, the stability of the coupling between the strengthening
plate and the heel insole is advantageously ensured by the inner or outer teeth formed
by the fork.
[0037] In the area of the other end, the mutual coupling between the strengthening plate
and the heel insole is obtained by traditional techniques, that is by using buttons
and/or pins, or by punching the through hole in order to define a toothed crown turned
toward the heel insole.
[0038] Consequently, the operations of coupling and/or removing of the strengthening plate
to/from the heel insole are particularly simple and rapid, which has a positive effect
on the production costs.
[0039] Therefore, the strengthening plate proposed by the present invention assures high
reliability and strength standards in any shoe use condition, without any change of
the shoes functionality.
[0040] It is to be pointed out that the positioning of the teeth in the inner area of the
fork allows to use, during the production thereof, parts of material which otherwise
would be waste material, i.e. off-cuts.
1. Strengthening plate for footwear, including a fork-like portion (2), formed in the
area of an end (A), defining at least one pair of prongs (2a,2b); means (3) for coupling
said strengthening plate (1) to a relative heel insole (10), said coupling means being
situated at least in the area of the other end (B);
characterized in that it includes at least one small tooth (4), situated in the area of said fork-like
portion (2) and extending substantially crosswise thereto, said small tooth (4) being
aimed at being fitted in said heel insole (10), in order to define a mutual coupling
between the latter and said strengthening plate (1), in cooperation with said coupling
means (3).
2. Strengthening plate, according to claim 1, characterized in that said small tooth (4) is situated in the inner area (20) of said fork-like portion
(2), i.e. in the area defined by the inner edges of the prongs (2a,2b).
3. Strengthening plate, aecording to claim 1, characterized in that said small tooth (4) is situated in the outer area of said fork-like portion (2),
i.e. in the area defined by the outer edges of the prongs (2a,2b).
4. Strengthening plate, according to any of the previous claims, characterized in that it includes, in the area of said fork-like portion (2), a plurality of small teeth
(4), extending substantially orthogonal to the fork-like portion (2), and aimed at
being fitted in said heel insole (10).
5. Strengthening plate, according to any of the previous claims, characterized in that it includes, in the area of the central body (C), that is in the area comprised between
said ends (A,B), at least one longitudinal groove (5), aimed at increasing at least
the bending resistance of said strengthening plate (1).
6. Strengthening plate, according to claim 5, characterized in that said central body (C) and said ends (A,B) connected thereto, define a substantially
curved plate with the concavity turned toward the heel insole (10).
7. Strengthening plate, according to claim 1, characterized in that said coupling means (3) include a through hole (30), made in the area of said end
(B), with the edges (30a) of said hole (30) forming a toothed crown (31), which is
aimed at being fitted in said heel insole (10) in order to obtain a mutual coupling
between the latter and said strengthening plate (1).
8. Strengthening plate, according to claim 1, characterized in that said coupling means (3) include a peg, made in said heel insole (10), aimed at snap-fitting
into said through hole (30), made in the area of the end (B) in order to obtain a
mutual coupling between the latter and said strengthening plate (1).
9. Strengthening plate, according to claim 1, characterized in that it includes, in the area of at least one prong (2a,2b) of said fork-like portion
(2), at least one additional groove (50), extending longitudinally with respect to
said prong (2a,2b) and aimed at increasing at least the bending resistance of said
fork (2).
10. Strengthening plate, according to claim 9, characterized in that it includes, in the area of each prong (2a,2b) of said fork-like portion (2), a corresponding
additional grooves (50) extending longitudinal to the relative prong (2a,2b).
11. Strengthening plate, according to claim 5, characterized in that said longitudinal groove (5) is substantially symmetrical with respect to said central
body (C) and substantially aligned with said prongs (2a,2b) of said fork-like portion
(2).
12. Strengthening plate; according to claim 11 and 7 or-8, characterized in that said longitudinal groove (5) is substantially aligned with said through hole (30).