WO2012018274A1

WO2012018274A1 - Anti-skid device for footwear

Info

Publication number: WO2012018274A1
Application number: PCT/RO2010/000011
Authority: WO
Inventors: Cornel Badea
Original assignee: Cornel Badea
Priority date: 2010-08-02
Filing date: 2010-08-02
Publication date: 2012-02-09

Abstract

This anti-skid device for footwear is a device made from a piece of steel strap by stamping, forming a clamp (16) with slanted drawn teeth, placed under the sole (17) of the footwear for anti-skid purposes. The clamp has two arms, which clench to the thickness of the footwear's sole and handles (7) for spacing the arms of the clamp. The clamp can be placed under the sole in a slot cut (18) that is made on the face of the sole and on the thickness of the sole. The clamp can be used without the slot cut, having spikes (11) on arms that pierce in the thickness of the sole, and teeth (10) pointing to the sole for preventing movements of the clamp.

Description

ANTI-SKID DEVICE FOR FOOTWEAR

Technical Field

This invention relates to an anti-skid device attached to footwear for preventing skidding on ice.

Background of the Invention

These kind of devices are present in a wide variety of forms, often using spikes mounted on various supports like rubber, plastic or metal. Using spikes in urban areas are uncomfortable due to frequent transition from dry to ice environment, also spikes will dull quickly and will not prevent slipping, even accentuating slippery on hard surfaces. Sandals with crampons are wide spread, but these are heavy and are difficult to take off and remount them frequently. A different approach is made in patent US2118778 where is described a device that uses as anti-skid element a non-linear rib where the fixture consists of a metal strip with upturned flanges which are attached to the heel. Another kind of anti-skid device is described in patent R0118690, which comprises a set of plates with drawn holes and a string for fixing to the footwear, but using a string for mounting the device creates some difficulties to placing the device on footwear.

Summary of the Invention

The anti-skid device that is described below is especially suitable for winter footwear with soles made of rubber and with thicker soles. It consists of a clamp made from a strap of steel having height elasticity endowed with slanted teeth pointing to the ground taking anti-skid, and teeth pointing to the sole. Fixing the device on footwear is accomplished by arms, which are made to the ends of the strip. Arms of the clamp are endowed with spikes that pierce into the thickness of the sole maintaining the clamp in place. The ends of extension arms are bent outwards to form handles for arms spacing. The clamp can be placed in a slot that is cut on the face of the sole and on the thickness of the sole. The clamp is maintained in position by; spikes on the amis of the clamp, slanted teeth pointing to the sole and the slot cut in which the clamp is placed. During use, because the teeth are slanted, they will wear out but remain sharp until exhaustion, the device keeping the anti-skid performance. Anti-skid teeth will not flatten because of weight bearing on them, even if the clamp is made of a thin steel strap (0.35mm), because the teeth are made by drawing material on the sides of the steel strap. The clamp can be easily mounted on the sole by handles, which are made to the end of the arms, and easily removed by simply pulling one of the handle. Clamp has a small volume and very little weight, because is missing additional support for teeth and has no additional parts for fixing on footwear. Users can walk on hard surfaces as concrete without creating discomfort and will not damage soft surfaces that walk, like linoleum or wood.

Description of the Drawings

Fig.1 shows a perspective view of a clamp with symmetrical placement of teeth. Fig.2 shows a perspective view of a clamp with asymmetrical placement of teeth. Fig.3 shows a perspective view of a clamp with symmetrical placement of teeth over a sole with a slot cut.

Fig .4 shows a front view of a clamp with symmetrical placement of teeth, mounted on sole.

Description of Preferred Embodir ients

Fig.1 shows the first embodiment of a clamp made from a strip of steel with slanted teeth made by drawing edges, the teeth pointing to the ground (9) with anti-skid function, and the teeth pointing to the sole (10) for preventing the clamp to slide on the sole. The portion of the strip, with drawn teeth, forms the base of the clamp. Clamp's base length is of the same with sole's width at place where the clamp is located, usually to the middle of the sole where the sole's width is largest.

On the sides of the clamp's base, teeth are placed symmetrically; the tooth pointing to the ground on one side corresponds with the tooth pointing to the ground on the opposite side. On the same side of the clamp's base, teeth are placed alternately; the tooth pointing to the sole follows the tooth pointing to the ground. Steel strap ends that exceed the width of the sole are bent (12) to form arms of the clamp (8), which clench to the thickness of the sole, and extremities of the arms are bent outward, forming handles (7) for spacing arms of the clamp. The clamp can have only one handle for mounting and removing from the sole. On the arms of the clamp and on the clamp's base, aside the bends (12) are made rectangular ditch cuttings (13) for lowering the force required for spacing the arms if the strap of steel is thick and stiff. On the arms of the ciamp, are made spikes (11) that are placed of a high lower then upper edge of the sole's thickness, spikes that pierce into the thickness of the sole to prevent movements of the clamp. Spikes can be made also on the edges of the arms of the clamp. The clamp (16) can be mounted in a slot (18) that is cut on the face of the sole (17) and on the thickness of the sole, the slot cut being of the same width of the clamp, preventing movements of the clamp. By placing the clamp in the slot cut, the force required for arms to press on sole can be lower, also spikes that pierce into the thickness of the sole can be omitted. The deep of the slot cut is around 1.50mm, sufficient for hindering the clamp to move. The drawn teeth pointing to the ground, are made with a slope among 20° and 60°, the greater the angle the greater the distance between sole and ground, 45° being the optimum angle. Sole-oriented teeth are around 1.50mm in height to provide a great friction between sole and the clamp's base. The lifetime of the clamp depends of the steel's thickness that is used. A clamp made from a steel strap of 16mm width and of 0.80mm thickness will lasts for a few winters seasons, weighting only 16-18.gr.

Fig.3 shows a clamp (16) with symmetrical placement of teeth over a sole (17) with a slot cut (18), having the arms gathered and making an angle of 70° with the clamp's base. After mounting on the sole the angle becomes 90°. Fig.4 represents the first embodiment of the clamp (16) mounted on the footwear's sole (17), viewed from the front of the footwear.

In Fig.2 is showed the second embodiment of the clamp, but with asymmetrically placement of the teeth. Different from the first embodiment is that the tooth pointing to the ground (15) on one side corresponds to the tooth pointing to the sole (14) on the opposite side and the tooth pointing to the sole (14) on one side corresponds to the tooth pointing to the ground (15) on the opposite side. Another difference is that the slanted teeth pointing to the sole and to the ground are of the same height. In this embodiment, the amis of the clamp are longer because there is an extra distance equal with the height of the teeth pointing to the sole. For the same width of the clamp and the same slope for the teeth, the distance between sole and ground is twice compared with the first embodiment, allowing to make a narrow clamp but with a lifetime reduced accordingly. For a clamp of 8mm width and the teeth slanted at 45°, the distance between sole and ground will be of 5,6mm, sufficient for taking anti-skid. Made from a strap of spring steel of 0.5mm thickness, a clamp for a medium of the footwer's size, 100mm the width of the sole, will weight only 5gr. An important feature of this device is that the teeth pointing to the sole and the spikes on the clamp arms that stuck in the thickness of the sole allows to not having belts or other additional means for attaching to the footwear. The friction force between clamp's base and sole created by the sole- oriented teeth, which is very high when the weight is pressing on the clamp's base, in addition with spikes that stuck in the thickness of the sole, will maintain the clamp in place, even without placing the clamp in the slot cut. The clamp can also be mounted to the heel portion of the sole. For having a good elasticity of the of the clamp, after manufacturing the clamp can be thermo treated. Due to the low cost for manufacturing and the small size and weight, the clamp can be made by footwear manufacturer and delivered with the footwear altogether.

Claims

1. Anti-skid device for footwear comprising a strap of steel characterized in that: a strap of steel placed under the sole of a footwear having a plurality of slanted drawn teeth on a portion of the strap making basis of a clamp, the portions of the strap that exceeds the width of the footwear's sole are bent to make arms of the clamp that clench to the thickness of the footwear's sole.

2. Anti-skid device for footwear according to claim 1 characterized in that; the arms of the clamp (8), to the outer ends shape, are bent outwards to make handles (7) for spacing the arms.

3. Anti-skid device for footwear according to claim 1 characterized in that; on the arms of the clamp are made spikes that pierce into the thickness of the footwear's sole (11).

4. Anti-skid device for footwear according to claim 1 characterized in that; the teeth on one side of the clamp's base are placed alternately, the tooth pointing to the sole follows the tooth pointing to the ground .

5. Anti-skid device for footwear according to claim 1 characterized in that; the teeth are placed symmetrically on the both sides of the clamp's base, the tooth pointing to the ground (9) on one side corresponds to the tooth pointing to the ground on the opposite side.

6. Anti-skid device for footwear according to claim 1 characterized in that; the teeth are placed asymmetrically on the sides of the clamp's base, the tooth pointing to the ground (15) on one side corresponds to the tooth pointing to the footwear's sole (14) on the opposite side.

7. Anti-skid device for footwear according to claim 1 characterized in that; on the arms of the clamp and on the clamp's base, aside the bends (12) between arms and base, are made rectangular cuttings (13).

8. Anti-skid device for footwear according to claim 1 further including a slot cut characterized in that; the slot (18) is made on the face of the sole and on the thickness of the sole, the slot being used for mounting the clamp in, having the same width of the clamp.