A shoe sole tread pattern

Abstract

A shoe sole for attaching to an item of footwear, the shoe sole having a tread pattern comprising a main channel 11 for extending between a fore part and a heel part of the footwear so as to separate

Description

FIELD OF THE INVENTION

[0001] The present invention relates to a shoe sole, and a shoe comprising the shoe sole. BACKGROUND OF THE INVENTION

[0002] Healthcare workers, including nurses, doctors, and other medical staff, operate in demanding work environments. To work effectively in these conditions, healthcare workers require footwear that provides excellent comfort, support, hygiene, and fluidhandling capabilities.

[0003] The range of movements that might be expected of a healthcare worker can often differ from other occupations, for instance requiring extended periods of relative inactivity around an operating table, that may involve many minor lateral adjustments in the position of the user. In tandem, the footwear must be able to effectively handle liquids underfoot to prevent slippages in these environments.

[0004] The present invention relates to a tread pattern intended to address the limitations of existing tread patterns. SUMMARY OF THE INVENTION

[0005] A first aspect of the invention provides a shoe sole for attaching to an item of footwear, the shoe sole having a tread pattern comprising: a main channel for extending between a fore part and a heel part of the footwear so as to separate a perimeter of the shoe sole into a first perimeter portion on a first side of the main channel and a second perimeter portion on a second side of the main channel; a first set of side channels spaced along the main channel, each side channel of the first set of side channels extending at an oblique angle from the main channel to open up on the first perimeter portion of the shoe sole; a second set of side channels spaced along the main channel, each side channel of the second set of side channels extending at an oblique angle from the main channel to open up on the second perimeter portion of the shoe sole; and a set of capillary channels, each capillary channel extending between two of: the main channel, the side channels, and a perimeter of the tread pattern, each capillary channel having a width less than the width of each of the side channels and main channel, wherein the main channel, side channels, and capillary channels form an interconnected network of channels, and wherein the capillary channels have a wave-like shape that undulates between two of: the main channel, the side channels, and a perimeter of the tread pattern.

[0006] In this manner, a shoe sole is provided with a tread pattern able to mitigate the effects of liquids underfoot. The main channel and angled side channels form the primary channels for directing liquid away from the sole, with the obtuse angle between the channels helping to direct the fluid more smoothly throughout the tread pattern.

[0007] The capillary channels extend through the space between the main and side channels to fill the space therebetween in a manner that provides for improved grip. In particular, the under surface of the tread pattern is cut into a multitude of under surface portions that improve grip, with the small width of the capillary channels ensuring a larger total under surface configured to contact the ground.

[0008] The wave-like pattern can improve the operability of the sole with different walking styles / gaits, as well as sideways movement that can be common for medical personnel.

[0009] The main channel and / or side channels and / or capillary channels may have a substantially constant width along their length.

[0010] This can provide a more even flow front through the channels.

[0011] Each capillary channel of the set of capillary channels may have the same width as each other capillary channel. Each side channel of the first and second sets of side channels may have the same width as each other side channel.

[0012] This helps to maintain substantially equal performance of each of the channels, as well as separate the functions of each of the types of channels, such that the main flow paths remain the main and side channels, whilst the capillary channels pick up any residual liquid between the main and side channels.

[0013] The width of the main channel and / or each side channels may be at least three times greater than the width of each capillary channel.

[0014] With this arrangement, the main and side channels act as the primary flow passages, whilst the small widths of the capillary channels allow the distance between channels to be minimised. This reduces the chances of liquids building up on the under surface of the sole, whilst increasing the surface area of the under surface.

[0015] Each side channel of the first and second sets of side channels may be substantially linear.

[0016] This minimising deviations in the flow path through the side channels.

[0017] The main channel, side channels, and capillary channels may have a common tread depth.

[0018] With this arrangement, liquid is able to flow more freely between the channels without any damming.

[0019] The side channels may extend from the main channel at an angle of between 40 and 50 degrees, preferably substantially 45 degrees.

[0020] This provides a compromise between improving the smooth flow of fluid in the same general direction, and shortening the lengths of the side channels to squeeze liquids more quickly from the channels.

[0021] The side channels may be arranged to extend from the main channel towards the fore part of the footwear.

[0022] A persons gait typically involves heel to toe impact on the footwear. With this arrangement, when the footwear impacts the heel first and rolls towards the toe, the liquid is directed more easily through the side channels to the sides of the sole.

[0023] Each set of side channels may comprise at least 5 side channels.

[0024] The tread pattern may comprise at least 10 capillaries between adjacent side channels of each set of side channels.

[0025] Each capillary channel may intersect with at least three other capillary channels.

[0026] This can provide an improved network of channels that help better distribute liquid throughout the tread pattern irrespective of the users gait or movement pattern, whilst also providing a multitude of under surface portions with angular joins that can improve grip.

[0027] The capillary channels may each meet the main channel or a side channel substantially perpendicular to the longitudinal axis of the respective main channel or side channel.

[0028] With this arrangement, the capillary channels can better manage any movement of the footwear perpendicular to the direction of the main or side channels. This can be particularly important in applications in which the user is likely to move sideways.

[0029] An under surface of the tread pattern may be configured to contact the ground. At least a major portion of the under surface may lie on a substantially flat plane.

[0030] This can provide improved stability to a user whilst standing still.

[0031] The tread pattern may be a first tread pattern, and the shoe sole may comprise a second tread pattern substantially the same as the first tread pattern.

[0032] The shoe sole may comprise an outsole having the tread pattern and a midsole in which the outsole is embedded.

[0033] An entire perimeter of the outsole may be embedded in the midsole.

[0034] The outsole may be embedded in the midsole more deeply towards a fore part of the shoe than a heel part of the shoe.

[0035] This helps protect the front of the outsole from catching on the floor, whilst maximising the usable tread depth towards the heel part where most wear can be expected.

[0036] A further aspect of the invention provides a shoe comprising the shoe sole of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Embodiments of the invention will now be described with reference to the accompanying drawings, in which:

[0038] Figure 1 shows a shoe according to an example of the invention;

[0039] Figure 2 shows a sole of the shoe;

[0040] Figure 3 shows a tread pattern of the sole;

[0041] Figure 4 shows an alternative example of a shoe sole; and

[0042] Figure 5 shows a cross-section of the tread pattern. DETAILED DESCRIPTION OF EMBODIMENT(S)

[0043] Figure 1 shows a shoe I comprising a shoe sole 2 and an upper 3. The item of footwear in this example is a clog. The clog may be suited to users in the healthcare profession, such as doctors and nurses, although it will be appreciated that the invention is applicable to a wide range of shoe types and applications.

[0044] The shoe 1 may be formed of a single material or a combination of materials. The shoe sole 2 may be formed of an elastomeric polymer, such as EVA or other synthetic polymer. The upper- 3 may be formed of the same material, or alternatively / additionally formed of a fabric material. A coating, such as a polyurethane coating, may be applied to the fabric material.

[0045] The shoe sole 2 is formed of an outsole 5 configured to contact a ground surface and a midsole 6 located between the outsole 5 and the upper 3, such as shown in figure 2. To protect the perimeter of the outsole 5, the outsole 5 is at least partially embedded in the midsole 6. In other words, the midsole 6 comprises a lip 6a forming a recess in which the outsole 5 is inserted. In the present example shown in figure 2, the outsole 5 is embedded in the midsole 6 around its entire perimeter such that the join line between the outsole 5 and the midsole 6 is recessed into the midsole 6. To account for frequent forward movement of the user, the outsole 5 may be arranged to protrude less at the fore part 8 of the shoe 1 compared to the heel part 9 of the shoe 1. For instance, the outsole 5 may be embedded in the midsole 6 more deeply towards a fore part 8 of the shoe 1 than a heel part 9 of the shoe 1. The outsole 5 has a constant thickness in the examples shown in figures 1-5, although it will be appreciated that the thickness of the outsole 5 may vary in other examples.

[0046] The shoe sole 2, in particular the outsole 5, includes a tread pattern that contacts the ground. At least a major portion of the under surface of the tread pattern lies on a substantially flat plane, for instance at least half of the under surface of the tread pattern. The portion of the under surface of the tread pattern that lies on a substantially flat plane may be referred to as a planar- portion P. In the present example, the planar portion P that lies on a flat plane extends across approximately 60% of the longitudinal extent of the shoe sole 2 and across the entire lateral extent of this longitudinal extent. This arrangement can provide improved stability to a user when standing still, which is a frequent requirement in the healthcare profession.

[0047] An example of the tread pattern is shown in figure 3. The tread pattern includes a main channel 11 having ends that open up at a perimeter of the outsole 5. The main channel 11 extends between a fore part 8 and a heel part 9 of the shoe 1 so as to split the perimeter of the outsole 5 into a first perimeter portion 5a on a first side of the main channel 11 and a second perimeter portion 5b on a second side of the main channel 11. The perimeter length of the first and second perimeter portions 5 a, 5b is substantially the same, e.g. within 10-20%, and preferably with 5-10%.

[0048] The tread pattern includes a first set of side channels 12 comprising a plurality of first side channels 12a extending from and spaced along the main channel 11. The tread pattern includes a second set of side channels 13 comprising a plurality of second side channels 13a extending from and spaced along the main channel 11. Each first side channel 12a extends at an oblique angle from the main channel 11 to open up on the first perimeter portion 5a of the shoe sole 2. Each second side channel 13a extends at an oblique angle from the main channel 11 to open up on the second perimeter portion 5b of the shoe sole 2.

[0049] The side channels 12a, 13a (only some of which are labelled) of the first and second sets of side channels 12, 13 are substantially similar in that each of the side channels 12a, 13a extend from the main channel 11 at an oblique angle of between 30 and 60 degrees, and optionally between 40 and 50 degrees. In the present example, each side channel 12a, 13a extends from the main channel 11 at the same oblique angle with respect to the main channel 11. The angle shown in figure 3 is approximately 45 degrees although it will be appreciated the side channels Ila, 12a may be inclined at any common angle.

[0050] The tread pattern is designed in a manner that increases the user’s grip, particularly in the presence of liquid on the surface beneath the shoe sole 2.

[0051] The oblique angle of the side channels 12a, 13a with respect to the main channel 11 can help liquid to escape from the underside. As a person’s gait typically involves heel to toe impact on the footwear, the side channels 12a, 13a are arranged to extend forwards from the main channel 11 towards the fore part 8 of the shoe 1. As a result of the heel-to-toe movement, any liquid underfoot is generally pushed forwards towards the fore part 8 of the shoe 1. The forward extending oblique inclination of the side channels 12a, 13a (i.e. non-perpendicular) thereby more easily guides excess liquid away from the main channel 11 into the side channels 12a, 13a. The angle of the side channels 12a, 13a with respect to the main channel 11 is typically chosen as a compromise between the shortest possible distance to the perimeter of the outsole 5, which is generally nearly perpendicular to the main channel 11, and a smaller angle that would limit the change in direction of the liquid as it exits the main channel 11 to a side channel 12a, 13a. Further, to minimise any change in direction of the liquid, each of the main channel 11 and side channels 12a, 13a may be substantially linear along its length.

[0052] To provide for an even distribution of liquid through the tread pattern, each of the main channel 11 and side channels 12a, 13a has the same width throughout its length. In the present example the width of the main channel 11 and side channels 12a, 13a is 2.5mm, although it will be appreciated that the width may vary in different examples. In some examples, the common width may be between 2mm and 3mm. In some examples, the main channel 11 may have a different width to the side channels 12a, 13a, for example the main channel 11 may have a greater width than the side channels 12a, 13a.

[0053] The first and second sets of side channels 12, 13 each comprise a plurality of side channels 12a, 13a. In the present example, each set of side channels 12, 13 comprises eight side channels 12a, 13a that extend from the main channel 11 although it will be appreciated that the sets of side channels 12, 13 may comprise any number of side channels 12a, 13a. For instance, each set 12, 13 may comprise at least 5 side channels 12a, 13a, or at least 8 side channels 12a, 13a. Further, each set of side channels 12, 13 may comprise fewer than 15 side channels 12a, 13a, or less than 12 side channels 12a, 13a.

[0054] The side channels 12a, 13a are typically evenly distributed along the length of the main channel 11 such that the distance between each side channel 12a, 13a of the respective set of side channels 12, 13 is substantially the same. This can provide a more even overall flow path for liquid through the tread pattern of the outsole 5.

[0055] Interspersed in the spaces between the main channel 11 and the side channels 12a, 13a are a set of capillary channels 14 comprising a plurality of capillary channels 14a. Each capillary channel 14a extends between any two of: the main channel 11, the side channels 12a, 13a, and a perimeter of the tread pattern. For instance, some capillary channels 14a may extend between a pair of side channels 12a, 13a on one side of the main channel 11, some may extend between the main channel 11 and a side channel 12a, 13a, some may extend from a side channel 12a, 13a to the perimeter, and others may extend from the main channel 11 to the perimeter.

[0056] The capillary channels 14a extend through the space between the main and side channels 11, 12a, 13a to fill the space therebetween in a manner that provides for improved grip. In particular, the under surface of the tread pattern is cut into a multitude of under' surface portions 15 that improve grip, with the small width of the capillary channels 14a maintaining a relatively large total under surface configured to contact the ground. The small size of the under-surface portions 15 formed by the capillary channels 14a means that any liquid gathered under an under-surface portion 15 is able to more easily escape into and through the interconnected network of channels formed by the main channel 11, side channels 12a, 13a, and capillary channels 14.

[0057] The capillary channels 14a in the present example each have a constant width of 0.75mm, although it will be appreciated that the capillary channels 14a may have any suitable width less than that of the main channel 11 and side channels 12a, 13a. The width of the main channel 11 and side channels 12a, 13a may be at least three times greater than the width of the capillary channels 14. In this manner, the main and side channels 11, 12a, 13a act as the primary flow passages, whilst the small widths of the capillary channels 14a allow the capillary channels 14a to be more tightly arranged without unnecessarily reducing the overall size of the under surface of the tread pattern in a manner that can increase wear.

[0058] Providing a plurality of capillary channels 14a can help reduce the potential for liquids to build up on the under surface of the shoe sole 2. In each space formed between the boundaries of adjacent the side channels 12a, 13a, the main channel 11 and the perimeter there may be at least 10 capillary channels 14a. Within this space, each capillary channel 14a may intersect other capillary channels 14a, for instance at least two, three or four other capillary channels 14a.

[0059] To provide for smoother liquid flow through the tread pattern, each of the main channel 11, side channels 12a, 13a and capillary channels 14a may have a common tread depth. The depth in the present examples is 1.6mm, as shown in relation to the second example shown in figures 5 and 6, however it will be appreciated that any suitable depth of channel may be provided to suit a par ticular application. For instance, the depth may be at least 1mm and less than 3 mm.

[0060] To accommodate the tread depth, the outsole 5 has a greater thickness than the depth of the channels of the tread pattern. In the present examples, the thickness of the outsole 5 is 3.5mm. The thickness of the outsole 5 is therefore 1.9mm thicker than the depth of the channels. In other examples, the thickness of the outsole 5 may be at least 1.5mm thicker than the depth of the channels.

[0061] The capillary channels 14a may intersect substantially perpendicularly. Similarly, the capillary channels 14a may each meet the main channel 11 or respective side channel 12a, 13a substantially perpendicularly. ‘Substantially perpendicular’ in this context is considered to be at least 80 degrees, and preferably at least 85 degrees. Where the capillary channel 14a intersects a linear main channel 11 or a linear- side channel 12a, 13 a, the angle of intersection between the capillary channel 14a and the further channel 11, 12a, 13a may be measured relative to the longitudinal axis of the main channel 11 of side channel 12a, 13a. The perpendicular nature of the capillary channels 14a may provide alternative auxiliary channels that are oriented in a different direction to the main and side channels 11, 12a, 13a that can provide benefits in applications in which the user is likely to move sideways. The lateral flow benefits of the capillary channels 14a may be further enhanced by aligning the openings of the capillary channels 14a on opposite sides of a respective main channel 11 or side channel 12a, 13a as shown most clearly in the magnified view in Figure 3.

[0062] Each capillary channel 14a has a smooth profile along its length without any sharp comers or vertices. The capillary channels 14a have a wave-like shape that undulates along its length. The undulations can improve the functionality of the shoe sole 2 for managing multiple walking styles / gait. In particular, the flow path of the capillary channels 14 varies in direction along its length to better manage liquid entering the capillary channels 14 from different directions. This can be particularly beneficial for users expected to move laterally, which can be a frequent need for medical personnel. The undulations further form more irregular patterns of the under-surface portions 14a which create an asymmetry on the tread pattern intended to provide improved traction.

[0063] In the present example of figures 2-3, the outsole 5 is shown as extending substantially across the entire length of the shoe sole 2. In alternative examples, such as shown in figures 4-5, the shoe sole 2 may comprise a first tread pattern and a second tread pattern. In this example, the first tread pattern is formed on a first outsole 5i and the second tread pattern is formed on a second outsole 5j. The first outsole 5i is positioned towards the fore part 8 of the shoe whilst the second outsole 5j is positioned towards the heel part 9 of the shoe. In other examples, the first and second tread patterns may be formed on a common outsole 5 but include a gap between the tread patterns.

[0064] Where the word 'or' appears this is to be construed to mean 'and / or' such that items referred to are not necessarily mutually exclusive and may be used in any appropriate combination.

[0065] Although the invention has been described above with reference to one or more preferred embodiments, it will be appreciated that various changes or modifications may be made without departing from the scope of the invention as defined in the appended claims. 04 10 24

Claims

1. A shoe sole for attaching to an item of footwear, the shoe sole having a tread pattern comprising:a main channel for extending between a fore part and a heel part of the footwear so as to separate a perimeter of the shoe sole into a first perimeter portion on a first side of the main channel and a second perimeter portion on a second side of the main channel;a first set of side channels spaced along the main channel, each side channel of the first set of side channels extending at an oblique angle from the main channel to open up on the first perimeter portion of the shoe sole;a second set of side channels spaced along the main channel, each side channel of the second set of side channels extending at an oblique angle from the main channel to open up on the second perimeter portion of the shoe sole; anda set of capillary channels, each capillary channel extending between two of: the main channel, the side channels, and a perimeter of the tread pattern, each capillary channel having a width less than the width of each of the side channels and main channel, wherein the main channel, side channels, and capillary channels form an interconnected network of channels, and wherein the capillary channels have a wave-like shape that undulates between two of: the main channel, the side channels, and a perimeter of the tread pattern, wherein the capillary channels each meet the main channel or a side channel substantially perpendicular to the longitudinal axis of the respective main channel or side channel.

2. The shoe sole of claim 1, wherein the main channel and / or side channels and / or capillary channels have a substantially constant width along their length.

3. The shoe sole of claim 1 or 2, wherein each capillary channel of the set of capillary channels has the same width as each other capillary channel and / or wherein each side channel of the first and second sets of side channels has the same width as each other side channel.04 10 244. The shoe sole of any preceding claim, wherein the width of the main channel and / or each side channels is at least three times greater than the width of each capillary channel.

5. The shoe sole of any preceding claim, wherein each side channel of the first and second sets of side channels is substantially linear.

6. The shoe sole of any preceding claim, wherein the main channel, side channels, and capillary channels have a common tread depth.

7. The shoe sole of any preceding claim, wherein the side channels extend from the main channel at an angle of between 40 and 50 degrees, preferably substantially 45 degrees.

8. The shoe sole of any preceding claim, wherein the side channels are arranged to extend from the main channel towards the fore part of the footwear.

9. The shoe sole of any preceding claim, each set of side channels comprising at least 5 side channels.

10. The shoe sole of any preceding claim, wherein the tread pattern comprises at least 10 capillaries between adjacent side channels of each set of side channels.

11. The shoe sole of any preceding claim, wherein each capillary channel intersects with at least three other capillary channels.

12. The shoe sole of any preceding claim, wherein an under surface of the tread pattern is configured to contact the ground, and wherein at least a major portion of the under surface lies on a substantially flat plane.

13. The shoe sole of any preceding claim, wherein the tread pattern is a first tread pattern, and the shoe sole comprises a second tread pattern substantially the same as the first tread pattern.

14. The shoe sole of any preceding claim, comprising an outsole having the tread pattern and a midsole in which the outsole is embedded.

15. The shoe sole of claim 14, wherein an entire perimeter of the outsole is embedded in the midsole.CM16. The shoe sole of claim 14 or 15, wherein the outsole is embedded in the midsole more deeply towards a fore part of the shoe than a heel part of the shoe.

17. A shoe comprising the shoe sole of any preceding claim.

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