Improvements to the attachment of anti-slip members to shoe soles equipped with retractable anti-slip means, and related manufacturing methods.

Abstract

An improved anti-slip device for a shoe sole of the type provided with anti-slip or anti-lateral slip means such as nails or gripping hooks, wherein such means are fixed to a rigid or semi-rigid means that can be folded into grooves obtained in the shoe sole itself, rather than being directly fixed to the shoe sole, and each anti-slip member (10) and its member (24) fixed to the shoe sole and provided with its own snap fastening means (25) are non-disassemblable by a joint (14) having a double-ended steel pin (15) with a protruding end that forms a pivot axis from which the anti-slip member (10) can rotate 180°, the joint having an eyelet (18) and a protruding attachment (16) on the opposite side that forms a pivot center of 90° of the axle (26) of the member element (24) fixed to the shoe sole, and is perpendicular to the steel pin (15) so that the fixing member (24) cannot be separated from the anti-slip member (10). Once the joint (14) is molded from a suitable plastic material, it is incorporated by overmolding using another plastic material having a different melting point, and together with the fastening member (24) and the anti-slip member (10), thus avoiding accidental separation of the assembly while maintaining the degrees of freedom of movement of the different components.

Description

Technical Field

[0001] The present invention relates to an improvement of an anti-slip device for a shoe sole of a type provided with anti-slip or anti-skid means such as nails or gripping hooks fixed to a rigid or semi-rigid means that can be folded into a groove obtained in the shoe sole itself rather than directly fixed to the shoe sole (sole), and a related manufacturing method.

Background Art

[0002] More specifically, the present invention relates to an improvement in the fixing of a support member of an anti-slip means to a shoe sole, which can be used and is hereinafter referred to as an anti-slip member for the sake of brevity, and a related manufacturing method. In any of the anti-slip devices disclosed in Patent Document 1, the anti-slip means is obtained from a first groove or recess obtained on the shoe sole and transferred to a second groove that is mirror-symmetrical to the previous one, in which the gripping hook is accommodated in a suitable cavity corresponding to the bottom of the groove accommodating the rigid member. It is fixed on a reversible rigid or semi-rigid member, preferably made of a semi-rigid plastic material. The inversion / lifting of the support member (bar, arch, or even a more complex form) occurs around an axis in the same plane as the shoe sole by pins protruding from both sides of its lower end. The pins are snap-fastened to respective rotating sheets obtained in a cube provided with mushroom pins fixed in a special cavity obtained in the side shoe sole of the groove accommodating the support member of the anti-slip means. Or, in the anti-slip device disclosed in Patent Document 2 by the same applicant, the anti-slip means is hinged to the shoe sole like a flag so as to be liftable with respect to the shoe sole, and is fixed to a rigid or semi-rigid support member that is rotatable by at least 180° with respect to its symmetry axis, which is different from and not parallel to the axis of hinging / lifting with respect to the shoe sole. A single groove is used to draw in the surface by the gripping hook when they do not need to contact the ground.

[0003] In both cases, the hinge / rotating sheet of the anti-slip member is not obtained integrally with the member itself, but rather on an auxiliary member (in this case, in the form of a parallelepiped or cube) that is fixed to the sole as a foot by the mushroom member on which they are provided, which is snapped to a corresponding sheet configured to be molded in the sole adjacent to a groove that houses a reversible support member after inversion, thereby preventing simple twisting of the bottom from causing detachment and loss without compromising the integrity of the sole itself.

[0004] However, it is emphasized that any replacement due to accidental damage, loss, or wear resulting from continuous and long-term use of the reversible anti-slip member is quite inconvenient, as the tensile force required to pull the reversible member away from its fixing sheet is many times greater, leaving the fixing mushroom a cube fixed to the sole. This is because, when intervention in the sole is necessary to elastically force it away, the maximum stress occurs precisely in the rotating sheet of the reversible anti-slip member obtained within the cube, which is not integral to the body of the same reversible member and can be easily removed from there, while remaining fixed to the sole.

[0005] This obviously leads to longer replacement times, as it also requires the manual removal of the cube from its housing sheet inside the sole.

[0006] It has also been noted that previous solutions used a joint that formed a rotating and / or reversing seat for the anti-slip member, and that this joint was provided with a double-ended steel through pin that allowed a 180° rotation of the anti-slip member, and another steel protruding pin perpendicular to it, which instead formed a 90° rotation axis for the same anti-slip member, and thus the mushroom coupling was inserted into this joint using a special machine after the entire system was completed. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Italian Patent No. 102017000024298 [Patent Document 2] European Patent No. 1558103 [Overview of the Initiative]

[0008] However, this solution is complex and significantly increases manufacturing time and cost. The first objective of the present invention is to overcome all the shortcomings of the prior art described above, provided that a member of the anti-slip member fixed to the sole of the shoe forms a single body with means such as a mushroom member that allows it to be fixed to the sole itself, and is connected in an inseparable manner to a rigid or semi-rigid material member that forms a rotating and / or inverting sheet of the anti-slip member, thereby constituting an innovative joint that forms a single body with the anti-slip member and avoids any possible division of the assembly.

[0009] Another objective of the present invention is to overcome all the shortcomings of the prior art described above, provided that the connection between the member fixed to the sole and the rigid or semi-rigid material member forming the rotation and / or inversion sheet of the anti-slip member is obtained when they are molded and, by overmolding, allows for the molding of a single body from the same material from which the above members are obtained, while maintaining the degrees of freedom of movement of the different components but avoiding accidental division of the assembly.

[0010] Therefore, even if the elastic force required to remove the anti-slip member is applied to the sole of the shoe, the member fixed to the sole cannot be removed from the anti-slip member.

[0011] According to a preferred embodiment of the present invention, such results are achieved by providing a joint molded from a plastic material, comprising a first steel pin projecting upward along its axis of symmetry, thereon intended to form a pivot axis on which the anti-slip member can rotate 180° to invert, switching from a resting position to an operating position, while below the joint, there is provided an eyelet-shaped perforated attachment that, in subsequent overmolding, forms a sheet intended to form a member fixed to the sole, with respect to a pivot axis on which the joint can rotate 90° with respect to the fixing plane, and is 180° perpendicular to the first pivot axis, thereby allowing the anti-slip member to move with a sufficient angular stroke, rising from the containment imprint and enabling a complete inversion. In such a configuration, once molded, the joint is inherent to the entire structure and is loaded into a mold containing the shapes of both the anti-slip member and the member with the sole fixing means, positioning the joint between the shape of the anti-slip member and the shape of the fixing member.

[0012] According to a unique feature of the present invention, a plastic material having a melting point different from the melting point of the material from which the joint is made is used for subsequent molding of the entire structure.

[0013] By molding two components and simultaneously overmolding a joint, a structure is obtained integrally comprising a support member for the anti-slip means, the aforementioned joint, and a component having one or more fastening means for positioning and securing it to the sole. Thus, the entire structure allows both lifting the anti-slip member relative to the component that secures the anti-slip member to its containment imprint obtained in the sole, and rotating the same anti-slip member 180° relative to the same securing component, so as to invert the anti-slip member when intended to switch from an operating position to a resting position or vice versa. All of the above is done while avoiding accidental release. This is because the two different materials from which the pieces of the structure are made, for example TPU and nylon as described below, are not bonded to each other in any way, and the overmolding allows the parts to be connected by steel pins protruding from a joint embedded in the anti-slip member, and by the formation of a horizontal axis perpendicular to the one to which the component secured to the sole is connected to the same joint, but because there is no adhesion between the two materials that form them, the parts can rotate freely to each other.

[0014] The joints and components fixed to the soles are fabricated, and the materials shown herein as preferred exemplary embodiments are nylon and TPU, but it should be noted that such selection is not mandatory, as it is sufficient to use suitable plastic materials that have different melting points and do not adhere to each other when overmolded.

[0015] The use of the fittings described and subsequent overmolding avoids the need to integrally load steel pins while the member is fixed to the sole when molding conventional fittings that are replaced by pins obtained in the overmolding step, thereby reducing both production time and cost. Furthermore, when overmolding the fittings from nylon having a different plastic material with a different melting point, in this case thermoplastic polyurethane TPU, the entire structure of the finished reversible member with the coupling means is obtained, thus eliminating the need to separately mold the mushroom coupling means, and subsequently eliminating the need to assemble the mushroom coupling after the system is completed, as well as avoiding accidental release of the mushroom coupling from the steel pin.

[0016] Further features and advantages of the present invention will become apparent from the accompanying drawings, which show only a non-limiting example of a preferred embodiment having two mushrooms of a member fixed to the sole of a shoe. In the drawings, Figures 1 to 5E relate to a prior art system in use. [Brief explanation of the drawing]

[0017] [Figure 1] This shows a known type of anti-slip member, the first of its kind, in which a joint is connected to the sole of a shoe via two separately molded mushrooms. [Figure 2] Figure 1 shows two mushrooms manually assembled with the same joints, ready to be fixed to the sole in the working position. [Figure 3] The previous diagram shows the step of removing the anti-slip member by pulling force from its fixing sheet on the sole of the shoe, highlighting a common defect: one of the fixing mushrooms remains fixed to the sole of the shoe rather than being integrated with the rest of the structure, thus increasing the replacement time. [Figure 4]The step of pulling out the anti-slip member of the previous figure by the pulling force from its fixing sheet on the shoe sole is shown, and the actually frequently seen defects are highlighted, that is, one of the fixed mushrooms is not integral with the rest of the structure and remains fixed to the shoe sole, thus lengthening the replacement time. [Figure 5A] It is an exploded view of different components forming another more recent joint of the anti-slip member, and as shown in Figure 5B, it shows the need for a complicated and cumbersome assembly of its different components, including a nylon joint with a double-ended pin for a 180° rotation, the insertion of a steel pin for a 90° rotation, and an overmold of the TPU arch. [Figure 5B] A side view of the anti-slip member with the gripping hook facing upward is shown. [Figure 5C] A perspective view of the same anti-slip member before attaching the mushroom coupling shown in Figure 5D is shown. [Figure 5D] Finally, a side view of the anti-slip member with the gripping coupling facing downward after manual assembly of the mushroom coupling is shown. [Figure 6A] It is a view of the components forming the joint according to the present invention. The joint is provided with an attachment having an eyelet on one side, and on the opposite side, a part of the double-ended pin protrudes for a 180° rotation of the anti-slip member. [Figure 6B] It is a partial cross-sectional view of the structure or composite according to the present invention obtained by overmolding the joint of Figure 6A. It is from a plastic material having a melting point different from the melting point of the material from which the joint is made. The mushroom coupling is directly made of the same material that also makes the 90° rotation pin of the anti-slip member when molding the entire composite. [Figure 6C] A perspective view of the same structure or composite as in Figure 6B, having an anti-slip member, a joint, and a fixing member provided with only a single mushroom coupling as a non-limiting example. [Figure 6D] A side view of the composite of Figure 6C, with the gripping hook of the anti-slip member facing downward. [Figure 7]Since the removal of the anti-slip member having a gripping hook according to the present invention is an essential part of a single structure, a method is shown that can be easily carried out with a simple pulling force that allows it to be completely pulled out from its fixing sheet together with the fixing mushroom (s). [Figure 8] Since the removal of the anti-slip member having a gripping hook according to the present invention is an essential part of a single structure, a method is shown that can be easily carried out with a simple pulling force that allows it to be completely pulled out from its fixing sheet together with the fixing mushroom (s). [Figure 9] In different embodiments, a composite body consisting of the anti-slip member, joint and fixing member of FIG. 6 is shown, which is obtained integrally after overmolding, positioned in its housing imprint in the shoe sole, and when lifted from the same imprint, it rotates partially with respect to the members connecting it to the shoe sole, respectively. [Figure 10] In different embodiments, a composite body consisting of the anti-slip member, joint and fixing member of FIG. 6 is shown, which is obtained integrally after overmolding, positioned in its housing imprint in the shoe sole, and when lifted from the same imprint, it rotates partially with respect to the members connecting it to the shoe sole, respectively.

[0018] The following figures show different steps of a method for manufacturing the anti-slip member of the present invention, which can take clearly different forms depending on the mold used. In particular,

[0019] [Figure 11] A plan view of a multi-imprint mold for molding a nylon joint is shown, which is manually loaded and molded so that the double-headed steel pins rotate 180°. [Figure 12] A nylon joint when the nylon joint including the steel pins comes out of the mold of FIG. 11 is shown. [Figure 13] The completed nylon joint with the pins reloaded into a simple circular design multi-imprint mold before TPU overmolding of the entire anti-slip system is shown. [Figure 14] This shows the entire anti-slip system with fittings, where a TPU structural coating is overmolded onto the nylon fittings. [Figure 15A] Figure 14 shows a vertical cross-sectional plan view and a horizontal cross-sectional elevation view of a structure or complex consisting of anti-slip members, joints, and fastening members. [Figure 15B] Figure 14 shows a vertical cross-sectional plan view and a horizontal cross-sectional elevation view of a structure or complex consisting of anti-slip members, joints, and fastening members. [Modes for carrying out the invention]

[0020] As seen in Figures 3 and 4, currently available solutions are not available as a single unit and, apart from involving several manual assembly steps, have the significant drawback of separating from each other under strong pulling forces. This often results in some fasteners becoming stuck in place during replacement, thus requiring further intervention over a considerable period of time.

[0021] In fact, the joint 4 is manufactured by inserting another steel pin 8, in addition to the double-ended steel pin 6, which allows for a 90° rotation, and into which the mushroom coupling 25 is inserted via a special machine after the system is completed. However, this does not guarantee the durability of the pin in place under large stresses that could lead to the release of the pin 8 from the mushroom coupling 25.

[0022] To avoid such drawbacks, the figures shown from Figure 6 onward illustrate several embodiments of the present invention, which are given only as non-limiting examples.

[0023] Referring to such a diagram, the object of the present invention is, A non-slip gripping hook holder member 10 made of a highly abrasion and chemical-resistant elastic material, preferably TPU, thermoplastic polyurethane, in the shape of a bar, arch, or more complex form, on which nails or gripping hooks 12 adapted to grip the surface of ice, snow and / or ice are dispersed; and a nylon joint 14 incorporating a double-ended steel pin 15 for 180° rotation of the gripping hook holder member 10, on the other hand, at the opposite end 16, an eye forming a seat for a 90° rotation axis 26 of a member 24 fixed to the sole of a shoe. A ret 18 is provided, which, as seen in the drawing, is instead perpendicular to the axis of rotation of the gripping hook holder member 10, and a member 24 fixed to the sole, which is made of TPU, i.e., the same thermoplastic material as the anti-slip member 10, and is adapted to be fixed to the sole via one or more fastening means integrated with it, such as the mushroom pin 25 shown in Figure 5D, which snaps to a corresponding sheet located in the sole adjacent to a groove that houses a reversible support member after inversion.

[0024] According to the present invention, once the nylon joint 14 is obtained by molding, it is reloaded onto a multi-imprint mold for molding the entire structure and positioned on the anti-slip member 10 together with its steel pin 15, thereby hinged like a flag, while at the opposite end, a TPU shaft 26 is formed by overmolding at the eyelet 18, which connects the joint to the fastening member 24.

[0025] Therefore, the joint 14 is integrated with both the anti-slip gripping hook holder member 10 and the member 24 fixed to the sole, which is obtained integrally with the mushroom pin 25, without preventing relative movement between the nylon and TPU, i.e., rotation and reversal, and this can also be achieved by using any other selected pair of suitable plastic materials having different melting points and not bonding to each other when overmolded.

[0026] Figures 11 onwards show: a) First, a step of molding a joint 14 from a plastic material, for example nylon, in a multi-layered mold A as shown (Figure 11), wherein double-ended steel pins are manually loaded so that each joint 14 carries a protruding steel pin 15, while at the opposite end, the joint is shaped to have a protruding attachment 16 having an eyelet 18 adapted to form the center of rotation of an axle 26 obtained in a later overmolding, which is integral with a fastening member 24 perpendicular to the axis of rotation of the anti-slip member, as shown in Figure 12. b) A step of providing a multi-imprint mold B configured to simultaneously mold a non-slip member 10 and member 24 fixed to the sole of a shoe, each equipped with a mushroom pin 25, via the joint 14 described above, c) Various steps for manufacturing the anti-slip system of the present invention are shown, including the steps of loading the joint 14 into the multi-imprint mold B, positioning it between the imprint of the anti-slip member 10 and the imprint of the member 24 fixed to the sole, performing the molding by selecting a plastic material having a different melting point than the melting point in which the joint 14 is molded, and overmolding the same joint to obtain the anti-slip member 10, the member 24 fixed to the sole, and the joint 14, thereby forming a single, integrally obtained structure. Thus, the member 24 fixed to the sole, together with its mushroom pin 25, as seen in Figures 9 and 10, is not detachable from the anti-slip member 10 even when an elastic force necessary to remove the sole is applied, without hindering their relative movement, i.e., rotation and reversal, because there is no adhesion between the materials forming them.

[0027] Preferred embodiments of the manufacture are described herein. It will be apparent that several modifications and alterations can be made by those skilled in the art without departing from the scope of protection of the present invention as defined by the claims set forth below, particularly in the number, position and shape of the fastening members supported by the members fixed to the sole.

Claims

1. An improved anti-slip device for a shoe sole of the type that is provided with anti-slip or anti-lateral slip means such as nails or gripping hooks, wherein such means are not fixed directly to the shoe sole but are fixed to a rigid or semi-rigid means that can be folded into a groove provided in the shoe sole, and each anti-slip member (10) and member 24 fixed to the shoe sole and provided with its own snap fastening means (25) are provided with a double-ended steel pin (15) having a protruding end that forms a pivot axis from which the anti-slip member (10) can rotate 180°. An improved anti-slip device for a shoe sole, comprising a joint (14) non-disassemblable, the joint having a projection attachment (16) on the opposite side having an eyelet (18) that forms a 90° rotation center of the axle (26) of the member element (24) fixed to the shoe sole, which is perpendicular to the steel pin (15), so that the fixing member (24) cannot be separated from the anti-slip member (10) even if an elastic force necessary for separation from the anti-slip member (10) is applied to the shoe sole.

2. An improved anti-slip device for a shoe sole according to claim 1, characterized in that an anti-slip member (10) and a fastening member (24) having fastening means (25) and axle (26) thereof are manufactured by integrally molding from the same plastic material to form a single piece overmolded such that a joint (14) is positioned between them, wherein the joint (14) is molded from a plastic material having a different melting point than the overmolded piece so as to integrate the joint (14) with both the anti-slip member (10) and the member (24) fixed to the shoe sole, but the materials of both members cannot bond to each other, and therefore do not prevent movement of both members relative to each other, i.e., rotational and reversal movements.

3. Anti-slip device for shoe soles according to claim 2, wherein the anti-slip members (10) and fastening members (24) having fastening means (25) thereof are molded from TPU (thermoplastic polyurethane) to form a single body by overmolding, and a joint (14) molded from nylon is positioned between them so as to integrate with both the anti-slip members (10) and the members (24) fixed to the shoe soles, but the materials of both members cannot adhere to each other because the nylon has a different melting point than the thermoplastic polyurethane used for overmolding, and therefore does not hinder relative movement toward each other, i.e., rotation and reversal movement.

4. The anti-slip device for a shoe sole according to any one of claims 1 to 3, characterized in that the fixing means for the member (24) fixed to the shoe sole is formed as one or more mushroom pins (25) fixed in a suitable cavity provided in the shoe sole on one side of the groove that accommodates the support member of the anti-slip means.

5. The anti-slip device for a shoe sole according to claim 4, characterized in that the fixing means of the member (24) fixed to the shoe sole is formed as a mushroom pin (25) aligned axially with the attachment (16) of the joint (14).

6. The anti-slip device for a shoe sole according to claim 4, characterized in that the fixing means of the member (24) fixed to the shoe sole is formed as two mushroom pins (25) positioned symmetrically with respect to the attachment (16) of the joint (14).

7. a) A step of forming a joint (14) supporting a protruding steel pin (15) from a plastic material, wherein the joint has a protruding attachment (16) having an eyelet (18) at the opposite end, and in the next overmolding, it is possible to form the rotation center of the axle (26) of a fixing member (24) perpendicular to the rotation axis of the anti-slip member, b) A step of providing a multi-imprint mold (B) configured to simultaneously mold both an anti-slip member (10) and a member (24) fixed to the sole of a shoe together with its fastening means (25) and shaft (26), wherein the joint (14) is positioned between them, c) Inserting the joint (14) into the multi-imprint mold (B), positioning it between the imprint of the anti-slip member (10) and the imprint of the fixing member (24) fixed to the sole, performing the molding by selecting a plastic material having a melting point other than the material of the joint (14), overmolding the joint to produce an integral structure integrally formed from the anti-slip member (10), the member (24) fixed to the sole using relative fixing means (25), the axle (26), and the joint (14), thereby preventing separation from the anti-slip member (10) without hindering the movement of both members relative to each other, i.e., rotational and reversal movements, even when an elastic force is applied to the sole necessary to separate the member (24) fixed to the sole using the fastening means (25) from the anti-slip member (10), the materials of both members cannot adhere to each other, i.e., preventing separation from the anti-slip member (10), A method for manufacturing the improved anti-slip device according to claim 1, characterized by the above.

8. A method for manufacturing an anti-slip device according to claim 7, characterized in that the material selected for forming the joint (14) is nylon, and the material for forming the entire structure is thermoplastic polyurethane (TPU).

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