GB2554779A

GB2554779A - A shoe including an electrical earthing member

Info

Publication number: GB2554779A
Application number: GB1709196.8A
Authority: GB
Inventors: Anderson Jenifer
Original assignee: Toffeln Ltd
Current assignee: Toffeln Ltd
Priority date: 2017-06-09
Filing date: 2017-06-09
Publication date: 2018-04-11
Anticipated expiration: 2037-06-09
Also published as: GB2554779B; GB201709196D0

Abstract

The shoe 10 has a sole 15 formed of electrically insulating material, e.g. closed cell foam or ethylene-vinyl acetate. When in use, the upper surface 70 of the sole 15 is in contact with the wearers foot while the lower surface of the sole 15 directly, or indirectly via an outsole, contacts the ground. A conductor 90 electrically connects the upper surface 70 with the ground to earth the shoe. The conductor 90 is in part located on the upper surface 70 of the sole 15 and contacts the lateral mid-region (160, figure 4) of the wearers foot. The conductor 90 prevents static build up, i.e. triboelectric charging. The location of the conductor 90 optimises contact with the wearers foot while minimising discomfort. The conductor 90 may be wedge-shaped with a surface flush with the upper surface 70 or formed of silicone rubber with carbon granules.

Description

(54) Title of the Invention: A shoe including an electrical earthing member Abstract Title: A shoe including an electrical earthing member (57) The shoe 10 has a sole 15 formed of electrically insulating material, e.g. closed cell foam or ethylene-vinyl acetate. When in use, the upper surface 70 of the sole 15 is in contact with the wearer’s foot while the lower surface of the sole 15 directly, or indirectly via an outsole, contacts the ground. A conductor 90 electrically connects the upper surface 70 with the ground to earth the shoe. The conductor 90 is in part located on the upper surface 70 of the sole 15 and contacts the lateral mid-region (160, figure 4) of the wearer’s foot. The conductor 90 prevents static build up, i.e. triboelectric charging. The location of the conductor 90 optimises contact with the wearer’s foot while minimising discomfort. The conductor 90 may be wedge-shaped with a surface flush with the upper surface 70 or formed of silicone rubber with carbon granules.

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A shoe including an electrical earthing member

The present invention relates generally to a shoe including an electrical earthing member and finds particular, although not exclusive, utility in clog-type shoes worn in work situations such as hospitals and kitchens.

Such shoes typically electrically insulate a wearer from the ground which means that in use friction between the underside of the shoe and certain types of floor surface can create an accumulation of electrostatic charge produced by the triboelectric effect. This charge will accumulate in the person wearing the shoes. When the person touches something, which allows the accumulated charge to dissipate, that person will receive a slight electric shock. Such shocks are unpleasant and potentially dangerous in certain situations.

Shoes which include an electrical connection member for “earthing” of the user are known, however such shoes are uncomfortable to wear due to the location and material used for the connection member.

It is therefore desirable to have a shoe which provides greater comfort to the user but which also prevents the accumulation of electro-static charge.

In one aspect, the invention provides a shoe including a sole comprised of electrically insulating material wherein the sole has an upper surface arranged to be in contact with a wearer’s foot, in use, and a lower surface arranged at least partially to be in contact with the ground either directly, or indirectly via an outsole, in use; the shoe further comprising an electrical connection member arranged to electrically connect the upper surface of the sole with the ground, in use, to prevent triboelectric charging of the shoe; wherein a portion of the electrical connection member is arranged on the upper surface of the sole such that in use it contacts with the lateral mid-region of the wearer’s foot.

In this regard, the lateral mid region of the wearer’s foot may be the portion adjacent to the 3rd metatarsal, the 4th metatarsal, the 5th metatarsal, the lateral cuneiform, and/or the cuboid bones.

Test data, discussed below, identifies this region as one which provides good contact between the shoe and foot, but with relatively low pressure exerted by the foot thus providing least impact on comfort.

The outsole may be integrally formed from the same material as the sole. Alternatively, it may comprise a relatively thin layer (for instance, approximately 4 to 6mm in thickness) applied to the underside of the sole. The outsole may provide antislip properties.

The outsole may comprise electrically conducting material and the electrical connection member may contact the upper surface of the outsole. In this way, an electrical connection is made between the wearer, as their foot touches the upper surface of the sole, and the ground via the outsole.

Regardless as to whether or not the outsole comprises electrically insulating material the electrical connection member may, in one example, extend through the outsole and contact with the ground directly such that an electrical connection is made between the wearer, as their foot touches the upper surface of the sole, and the ground, in use.

The shoe may further comprise an upper layer. The sole and the upper layer may be integrally formed. The electrically insulating material may comprise a closed cell foam. The electrically insulating material may comprise ethylene-vinyl acetate. The shoe may be at least partially manufactured using an injection moulding process. The shoe may be a moulded plastics shoe. The electrical connection member may comprise material which allows the flow of electricity relatively easily. The electrical connection member may comprise rubber, silicone, and/or silicone rubber including carbon granules. The shoe may be a clog-like shoe.

The electrical connection member may comprise a wedge shape portion, one surface of which is arranged to sit substantially flush with the upper surface of the sole. The wedge shape is arranged in the sole such that the thickest portion is towards the heel portion and the thinnest portion is towards the toe portion of the shoe.

The electrical connection member may comprise a lower contacting portion connected to the wedge shape portion, one surface of which is arranged to contact the upper surface of the sole, or the ground, in use. The two portions may be integral.

The above and other characteristics, features and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention. This description is given for the sake of example only, without limiting the scope of the invention. The reference figures quoted below refer to the attached drawings.

Figure 1 is an elevational view of the side of a shoe;

Figure 2 is a perspective view of the inside of the shoe of Figure 1;

Figure 3 is a perspective view of an electrical connection member; and

Figure 4 is a plan of a shoe sole.

The present invention will be described with respect to certain drawings but the invention is not limited thereto but only by the claims. The drawings described are only schematic and are nondimiting. Each drawing may not include all of the features of the invention and therefore should not necessarily be considered to be an embodiment of the invention. In the drawings, the size of some of the elements may be exaggerated and not drawn to scale for illustrative purposes. The dimensions and the relative dimensions do not correspond to actual reductions to practice of the invention.

Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequence, either temporally, spatially, in ranking or in any other manner. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that operation is capable in other sequences than described or illustrated herein.

Moreover, the terms top, bottom, over, under and the like in the description and the claims are used for descriptive purposes and not necessarily for describing relative positions. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that operation is capable in other orientations than described or illustrated herein.

It is to be noticed that the term “comprising”, used in the claims, should not be interpreted as being restricted to the means listed thereafter; it does not exclude other elements or steps. It is thus to be interpreted as specifying the presence of the stated features, integers, steps or components as referred to, but does not preclude the presence or addition of one or more other features, integers, steps or components, or groups thereof. Thus, the scope of the expression “a device comprising means A and B” should not be limited to devices consisting only of components A and B. It means that with respect to the present invention, the only relevant components of the device are A and B.

Reference throughout this specification to “an embodiment” or “an aspect” means that a particular feature, structure or characteristic described in connection with the embodiment or aspect is included in at least one embodiment or aspect of the present invention. Thus, appearances of the phrases “in one embodiment”, “in an embodiment”, or “in an aspect” in various places throughout this specification are not necessarily all referring to the same embodiment or aspect, but may refer to different embodiments or aspects. Furthermore, the particular features, structures or characteristics of any embodiment or aspect of the invention may be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments or aspects.

Similarly, it should be appreciated that in the description various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Moreover, the description of any individual drawing or aspect should not necessarily be considered to be an embodiment of the invention. Rather, as the following claims reflect, inventive aspects lie in fewer than all features of a single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention.

Furthermore, while some embodiments described herein include some features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form yet further embodiments, as will be understood by those skilled in the art. For example, in the following claims, any of the claimed embodiments can be used in any combination.

In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the invention may be practised without these specific details. In other instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

In the discussion of the invention, unless stated to the contrary, the disclosure of alternative values for the upper or lower limit of the permitted range of a parameter, coupled with an indication that one of said values is more highly preferred than the other, is to be construed as an implied statement that each intermediate value of said parameter, lying between the more preferred and the less preferred of said alternatives, is itself preferred to said less preferred value and also to each value lying between said less preferred value and said intermediate value.

The use of the term “at least one” may mean only one in certain circumstances.

The principles of the invention will now be described by a detailed description of at least one drawing relating to exemplary features of the invention. It is clear that other arrangements can be configured according to the knowledge of persons skilled in the art without departing from the underlying concept or technical teaching of the invention, the invention being limited only by the terms of the appended claims.

In Figure 1, a moulded clog-type left foot shoe 10 is depicted including a sole 15, an upper portion 20, a heel portion 30, a strap for surrounding the heel 40, pivoted 50 to the shoe 10 and air holes 60 located within the sides of the shoe.

In Figure 2, the inside of the shoe 10 is shown including the upper surface 70 of the sole 15, a heel portion 74 of the upper surface of the sole, a toe portion 72 of the upper surface of the sole, the strap 40 and pivot 50. Also shown is a hole 80 within the sole 15. This hole extends through from the upper surface 70 of the sole 15 to the underside of the sole. The shape of the hole 80 is substantially rectangular in the surface 70 of the sole 15.

An electrical connection member 90 is shown in Figure 3. It comprises a wedge shape portion 110 having a thicker end 130 and a thinner end 120 arranged at opposite ends thereof.

A ground contacting portion 100 is arranged on one of the surfaces of the wedge shape portion 110 which connects the thicker and thinner ends. This ground contacting member 100 is cylindrical with its axial bore lying perpendicular to the surface of the wedge shape portion on which it is arranged.

It is inserted into the hole 80 in the sole of the shoe 10 such that the surface of the wedge shape portion, opposite the surface on which the ground contacting member 100 is arranged, is uppermost and substantially flush with, or very slightly depressed relative to, the upper surface 70 of the sole 15.

The thicker end 130 is arranged towards the heel portion 74 of the shoe and the thinner end towards the toe portion 72 of the shoe 10. This is due to the sole not being planar but being shaped to accommodate a user’s foot comfortably. In this respect, the upper surface of the sole rises towards the area where the user’s arch will reside, in use, and thus the upper surface of the sole slopes downwards towards the toe portion in the area where the ground contacting portion 90 is arranged. Accordingly, the surface of the wedge shape portion, opposite the surface on which the ground contacting member 100 is arranged, is substantially parallel with the upper surface 70 of the sole 15 to avoid any discomfort to the user.

Although shown as cylindrical it is to be understood that the ground contacting portion 100 may have other shapes such as cuboid.

Figure 4 shows a plan of the upper surface of a typical shoe sole divided into eight major areas, each area divided into various cells. The eight major areas are the heel area 150 which comprises the bottom four rows of cells; the medial midfoot area 170 which comprises the four rows of cells above the heel area with four columns starting from the left hand side of the foot; the lateral midfoot area 160 which comprises the four rows above the heel area with three columns starting from the right hand side of the foot, the fourth and fifth metatarsal area 180 which comprises the four rows above the lateral midfoot area 160 with two columns starting from the right hand side of the foot; the first metatarsal area 200 which comprises the four rows above the medial midfoot area 170 with two columns starting from the left hand side of the foot; the second and third metatarsal area 190 which comprises the four rows and two columns between the first 200 and fourth and fifth 180 metatarsal area; the hallux area 210 being the big toe area above the first metatarsal area and comprising two rows each of two columns of cells with a single cell at the top; and the toe area 220 which comprises three rows of cells above the second to fifth metatarsal areas.

The table below lists peak pressures experienced in the various areas of the foot.

It can be seen that the maximum values are in the heel and hallux (big toe) areas.

Table 1: mean and peak pressures for all areas of the foot in current footwear.
Plantar foot region	Mean pressure	Peak pressure
Heel	32.75	102.31
Lateral midfoot	14.92	47.76
Medial midfoot	6.35	43.1
Metatarsal 4-5	18.15	65.38
Metatarsal 2-3	11.87	52.88
Metatarsal 1	12.22	54.47
Hallux	16.58	74.81
Toes	2.37	29.92

Research has also shown that discomfort is first felt, whilst standing, in either the heel or ball of the foot (metatarsal) regions for 99% of all trials. For the majority of trials, peak pressure and pain onset occurred in the same region. Further to this, in known shoes, the peak pressure at the ball of the foot (metatarsal regions) and the heel is greater than the midfoot regions of the foot.

Figure 4 also includes numbers in each cell. These are percentage contact of the upper surface of the with the foot over one minute standing. Data was collected from ten participants (five male, five female) using the Pedar in-shoe pressure system (Novel GmbH, Germany).

Two curving lines 230A, and 230B are shown in the midfoot regions. Between them is an area where the lower surface of the sole does not typically contact the ground in normal use due to the in-step of the shoe. Alternatively, in some examples it does contact the ground but is known as the “waist panel” and typically comprises electrically insulating material and no outsole.

Thus, to locate the optimum position of the ground contacting member the pressure, pain and ground contact portions are considered together. The result is a location 240 in the upper lateral midfoot area in the second and third columns counting from the right hand side of the shoe, and in the seventh and eight rows counting from the end of the heel area. This area was chosen because it is the place least likely to cause discomfort due to the lower peak pressures (Table 1) but also because it has a reasonable contact with the foot (up to 84% of the time). Furthermore, it avoids the medial midfoot region which does not have reliable contact with the ground and which is a much more sensitive area than the rest of the foot. It also avoids the toe region which does not have a good contact with the foot for the majority of time.

Claims

1. A shoe including a sole comprised of electrically insulating material wherein the sole has an upper surface arranged to be in contact with a wearer’s foot, in use, and a lower surface arranged to be in contact at least partially with the ground either directly, or indirectly via an outsole, in use; the shoe further comprising an electrical connection member arranged to electrically connect the upper surface of the sole with the ground, in use, to prevent triboelectric charging of the shoe; wherein a portion of the electrical connection member is arranged on the upper surface of the sole such that in use it contacts with the lateral mid-region of the wearer’s foot.

2. The shoe of claim 1, wherein the outsole comprises electrically conducting material and the electrical connection member contacts the upper surface of the outsole.

3. The shoe of either one of claims 1 and 2, wherein the electrical connection member contacts the ground in use.

4. The shoe of any preceding claim, further comprising an upper layer.

5. The shoe of claim 4, wherein the sole and the upper layer are integrally formed.

6. The shoe of any preceding claim, wherein the electrically insulating material comprises a closed cell foam.

7. The shoe of any preceding claim, wherein the electrically insulating material comprises ethylene-vinyl acetate.

8. The shoe of any preceding claim, wherein the shoe is at least partially manufactured using an injection moulding process.

9. The shoe of any preceding claim, wherein the shoe is a moulded plastics shoe.

10. The shoe of any preceding claim, wherein the electrical connection member comprises rubber, silicone, and/or silicone rubber with carbon granules.

11. The shoe of any preceding claim, in which the shoe is a clog-like shoe.

Intellectual

Property

Office

Application No: GB 1709196.8 Examiner: Dr Niall Deakin

11. The shoe of any preceding claim, wherein the electrical connection member comprises a wedge shape portion, one surface of which is arranged to sit substantially flush with the upper surface of the sole.

12. The shoe of claim 11, wherein the electrical connection member comprises a lower contacting portion connected to the wedge shape portion, one surface of which is arranged to contact the upper surface of the sole, or the ground, in use.

10 13. The shoe of any preceding claim, in which the shoe is a clog-like shoe.

Amendments to the claims have been filed as follows;

1. A shoe including a sole comprised of electrically insulating material wherein the sole has an upper surface arranged to be in contact with a wearer’s foot, in use;

5 the shoe further comprising an electrical connection member arranged to electrically connect the upper surface of the sole with the ground, in use, to prevent triboelectric charging of the shoe; wherein a portion of the electrical connection member is arranged on the upper surface of the sole such that in use the electrical connection member contacts with the lateral mid-region of the

10 wearer’s foot, the electrical connection member comprising a wedge shape portion, one surface of which is arranged to sit substantially flush with the upper surface of the sole, the wedge shape being arranged in the sole such that the thickest portion is towards the heel portion and the thinnest portion is towards the toe portion of the shoe.

2. The shoe of claim 1 including an outsole, wherein the outsole comprises electrically conducting material and the electrical connection member is arranged to contact the upper surface of the outsole.

20 3. The shoe of claim 1, wherein the electrical connection member is arranged to contact the ground in use.

4. The shoe of any preceding claim, further comprising an upper portion.

25 5. The shoe of any preceding claim, wherein the electrically insulating material comprises a closed cell foam.

6. The shoe of any preceding claim, wherein the electrically insulating material comprises ethylene-vinyl acetate.

7. The shoe of any preceding claim, wherein the shoe is a moulded plastics shoe.

8. The shoe of any preceding claim, wherein the electrical connection member comprises rubber, silicone, and/or silicone rubber with carbon granules.

9. The shoe of claim 2, wherein the electrical connection member comprises a lower contacting portion connected to the wedge shape portion, one surface of which is arranged to contact the upper surface of the outsole in use.

5 10. The shoe of claim 3, wherein the electrical connection member comprises a lower contacting portion connected to the wedge shape portion, one surface of which is arranged to contact the ground in use.