Body Protection

Abstract

This invention relates to a structure for absorption and/or dissipation of mechanical shocks comprising: connectors forming an aerated base with a base surface; protuberances, each of the protuberances comprising a central axis along which it extends from the aerated base, the central axis being normal to the base surface, two adjacent protuberances being connected to each other by a connector.

It also relates to a body protector at least partly made using the structure and protective clothing comprising at least one such protector.

Claims

1. Structure for absorption and/or dissipation of mechanical shocks comprising: connectors forming an aerated base with a base surface; protuberances, each of the protuberances comprising a central axis along which it extends from the aerated base, the central axis being normal to the base surface, two adjacent protuberances being connected to each other by a connector.

2. Structure according to claim 1, wherein the ratio between the height of the protuberances and the thickness of the aerated base is 6 to 17.

3. Structure according to claim 1, wherein breathability of the structure is 10 to 70%.

4. Structure according to claim 1, wherein the Shore A hardness of the structure is 5 to 90.

5. Structure according to claim 1, wherein the ratio between the equivalent outside diameter of the protuberances measured at the base surface and the distance between the central axes of two adjacent protuberances is 0.65 to 1.5.

6. Structure according to claim 1, wherein the protuberances are all on the same side of the aerated base.

7. Structure according to claim 1, wherein each protuberance has an external wall which has a circular symmetry about the central axis or can be superposed on its image by a 360/n rotation about the central axis, where n is an integer greater than 1.

8. Structure according to claim 1, wherein the equivalent outside diameter of the protuberances is constant from the aerated base or decreases linearly from the aerated base with an angle of more than 0 and equal or less than 30.

9. Structure according to claim 1, wherein each of the protuberances has a through or blind orifice therein, and which extends along the central axis and defines an internal wall of the protuberance.

10. Structure according to claim 1, wherein the internal wall has a circular symmetry about the central axis or can be superposed on its image by a 360/n rotation about the central axis, where n is an integer greater than 1.

11. Structure according to claim 1, wherein the equivalent inside diameter of the protuberances: is constant from the aerated base or decreases linearly from the aerated base with an angle of more than 0 and equal or less than 30, or increases linearly from the aerated base with an angle of more than 0 and equal or less than 30.

12. Structure according to claim 1, wherein the structure is made of a viscoelastic material.

13. Structure according to claim 12, wherein the majority constituent of the viscoelastic material is a polymer.

14. Body protector made at least partially from the structure according to claim 1.

15. Body protector according to claim 14 achieving at least performance level 1 in standard EN1621-1: 2013 or in standard EN1621-2: 2014.

16. Protective clothing comprising at least one protector according to claim 14.

17. Structure according to claim 1, wherein the protuberances are on each side of the aerated base.

18. Structure according to claim 1, wherein each protuberance has an external wall which can be superposed on its image by a 60/n rotation about the central axis.

19. Structure according to claim 1, wherein each protuberance has an internal wall which can be superposed on its image by a 60/n rotation about the central axis.

20. Structure according to claim 12 wherein the majority constituent of the viscoelastic material is chosen from the group consisting of: polynorbornene, polyacrylonitrile, polyvinyl chloride (PVC), the ethylene vinyl acetate (EVA) copolymer, chlorobutyl rubber and mixtures thereof.

Description

DESCRIPTION OF THE DRAWINGS

[0069] The appended drawings are given for illustrative and non-limitative purposes to help the reader better understand this invention. These drawings include the following figures:

[0070] FIG. 1 is an oblique projection view of a particular embodiment of the structure for absorption and/or dissipation of mechanical shocks according to the invention with cylindrical protuberances with a circular base;

[0071] FIG. 2 is an oblique projection view of a particular embodiment of the structure for absorption and/or dissipation of mechanical shocks according to the invention with cylindrical protuberances with a regular hexagon shaped base;

[0072] FIG. 3 is a cross section perpendicular to the aerated base passing through the central axis of the protuberances; and

[0073] FIG. 4 is a top view of a protector according to the invention made entirely using the structure for absorption and/or dissipation of mechanical shocks according to the invention.

DESCRIPTION OF THE INVENTION

[0074] The same numeric references are used to designate equivalent elements in all the figures.

[0075] One particular example of the absorption and/or dissipation structure according to the invention is described below with reference to FIG. 1. The structure 1 is homogeneous.

[0076] This structure 1 for absorption and/or dissipation of mechanical shocks comprises connectors 2 forming a plane aerated base B with a base surface. The connectors are in the form of a strip with plane surfaces with the same length.

[0077] The structure 1 for absorption and/or dissipation of mechanical shocks also includes protuberances 3, each of the protuberances comprising a central axis AA along which it extends from the aerated base B, the central axis AA being normal to the base surface.

[0078] The protuberances 3 are present on only one side of the aerated base B. Each protuberance 3 has an external wall 31, the external wall 31 having a circular symmetry about the central axis. Each of the protuberances 3 has a through orifice which extends along the central axis AA and defining an internal wall 33 of the protuberance 3. The internal wall 33 has a circular symmetry about the central axis AA. The protuberances 3 are distributed in a regular triangular mesh pattern, in other words each of the protuberances has six neighbours and the central axes of the neighbours form a regular hexagon.

[0079] Another particular example of the absorption and/or dissipation structure according to the invention is described below with reference to FIG. 2. The structure 1 is homogeneous.

[0080] This structure 1 for absorption and/or dissipation of mechanical shocks comprises connectors 2 forming a plane aerated base B with a base surface. The connectors are in the form of a strip with plane surfaces with the same length.

[0081] The structure 1 for absorption and/or dissipation of mechanical shocks also includes protuberances 3, each of the protuberances comprising a central axis AA along which it extends from the aerated base B, the central axis AA being normal to the base surface.

[0082] The protuberances 3 are present on only one side of the aerated base B. Each protuberance 3 has an external wall 31, the transverse cross section of the external wall 31 being a regular polygon with 6 vertices (regular hexagonal polygon). Each of the protuberances 3 has a through orifice which extends along the central axis AA and defines an internal wall 33 of the protuberance 3. The transverse cross section of the internal wall 33 is a regular polygon with 6 vertices. The vertices of the regular polygons forming the transverse cross section of the external and internal walls are angularly aligned. The protuberances 3 are distributed in a regular triangular mesh pattern, in other words each of the protuberances has six neighbours and the central axes of the neighbours form a regular hexagon.

[0083] FIG. 3 shows an exemplary cross section perpendicular to the aerated base for the exemplary structures for absorption and/or dissipation of mechanical shocks of FIGS. 1 and 2.

[0084] On FIG. 3, the equivalent outside diameter D.sub.e of the protuberances 3 decreases linearly from the aerated base B with an angle of 6 while the equivalent inside diameter D.sub.i of the protuberances 3 increases linearly from the aerated base B at an angle of 6.

[0085] An example of the dimensions of the different elements of the structure for absorption and/or dissipation of mechanical shocks is given in table 1 below.

TABLE-US-00001 TABLE 1 Structure for absorption and/or dissipation of mechanical shocks thickness 6.8 mm Protuberances height 6 mm equivalent outside diameter at the 9.5 mm aerated base protuberance thickness 1 mm Connectors length 1.7 mm width 3 mm thickness 0.8 mm

[0086] Table 2 below gives an exemplary composition for the material used for the structure for absorption and/or dissipation of mechanical shocks. Quantities are expressed as a percentage by weight of the total composition.

TABLE-US-00002 TABLE 2 Polynorbornene 45% Oils 40% Silica 6% Anti-scratch agent 1% Vulcanising agent (sulphur) 1% Vulcanisation accelerator 1% Colouring agent 1% Stearic acid <1% Antioxidant <1% UV stabiliser (wax) <1% The total does not add up to 100%, due to approximations.

[0087] The structure for absorption and/or dissipation of mechanical shocks with one of the configurations of FIGS. 1 to 5 and with the composition given in table 2 has a breathability of about 35% and a Shore A hardness of about 25. This structure make it possible to reach performance level 2 for standard EN1621-1 and level 1 for standard EN1621-2.

[0088] An exemplary body protector is described below with reference to FIG. 4. This exemplary body protector corresponds to the examples given in standard EN1621-1: 2013 (see FIG. 1 and table 1 in this standard). The body protector 10 can easily be defined using three parameters: two radii r.sub.1, r.sub.2 and a length l. It comprises three parts centred on a longitudinal axis BB which is also an axis of symmetry of the body protector 10. A first end part 11 has the shape of a half-circle with radius r.sub.1 and a second end part 12 has the shape of a half-circle with radius r.sub.2. The two end parts 11, 12 are connected to each other by a trapezoidal shaped central part 13 with the longitudinal axis BB as the axis of symmetry and height l.

[0089] Such a shape can be used to protect the following parts of the body: shoulder (S); elbow and forearm (E); hip (H); knee and upper part of the tibia (K); knee, upper and middle parts of the tibia (K+L); lower part of the tibia (L).

[0090] Table 3 below gives the minimum dimensions of the three parameters according to standard EN1621-1: 2013.

TABLE-US-00003 TABLE 3 Small model Large model Type r.sub.1 r.sub.2 l r.sub.1 r.sub.2 l S 55 32 64 70 40 80 E 45 24 118 50 30 150 K 55 24 100 70 30 130 H 35 26 70 44 33 88 L 32 24 64 40 30 80 K + L 55 24 185 70 30 240