JP-7857264-B2 - Impact absorbing structure and method for manufacturing an impact absorbing structure

JP7857264B2JP 7857264 B2JP7857264 B2JP 7857264B2JP-7857264-B2

Inventors

鴻巣敦宏

Assignees

一般財団法人日本自動車研究所

Dates

Publication Date: 20260512
Application Date: 20231116

Claims (8)

An impact-absorbing structure that mitigates external forces, Multiple spherical cushioning materials, which achieve the target shock absorption performance through a single-layer structure, It comprises multiple layers of fabric that overlap each other, having an area large enough to encompass the protective area of the human body provided by the aforementioned spherical cushioning material, The fabric has storage line joints that are joined linearly at equal intervals with a width of approximately half the circumference of the selected spherical cushioning material, and outer circumference line joints that are joined linearly around the outer circumference of the outermost spherical cushioning material when multiple spherical cushioning materials covering the protective area are stored together. The spherical cushioning material is stored and arranged in each of the multiple rows of storage spaces formed by the storage line joints and outer peripheral line joints of the overlapping fabrics, and the spherical cushioning material in adjacent rows is arranged alternately with an offset of approximately the radius . The aforementioned spherical cushioning material is an impact-absorbing structure characterized by performing a pre-impact test or dummy impact test in which a head impactor having the same rigidity as a human head is free-dropped from a height position according to the JCF safety standard toward a collection of cushioning materials arranged in a single layer, and selecting a cushioning material with a shape and material such that the test results using three-axis composite acceleration fall below the prescribed JCF safety standard .
In the impact absorbing structure described in claim 1, The shock-absorbing structure is characterized in that the fabric is a mesh fabric with elasticity and a coarseness that allows the spherical cushioning material stored in the storage space to be seen through it.
In the impact absorbing structure described in claim 1 or 2 , The aforementioned impact-absorbing structure is characterized by being an impact-absorbing sheet that is incorporated into a hat body made of a flexible material to serve as a head protector.
In the impact absorbing structure described in claim 3 , The aforementioned impact-absorbing sheet is a head-top impact-absorbing sheet in which the area of the human body protected by the spherical cushioning material is the top of the head. The impact-absorbing structure is characterized in that the shape of the outer peripheral line joint portion of the head impact-absorbing sheet is a polygonal or circular shape that corresponds to the shape of the head.
In the impact absorbing structure described in claim 3 , The aforementioned shock-absorbing sheet is a head-side shock-absorbing sheet in which the area of the human body protected by the spherical cushioning material is the head side, The impact-absorbing structure is characterized in that the head-side impact-absorbing sheet has a rectangular shape at the outer peripheral line joint that corresponds to the shape of the head-side portion when wrapped around it.
In the impact absorbing structure described in claim 3 , The aforementioned impact-absorbing sheet is a head-whole impact-absorbing sheet in which the area of the human body protected by the spherical cushioning material covers the entire head. The impact-absorbing structure is characterized by comprising a combination structure of a top-of-the-head impact-absorbing sheet having a polygonal or circular shape at the outer peripheral line joint that corresponds to the shape of the top of the head, and a side-of-the-head impact-absorbing sheet having a rectangular shape at the outer peripheral line joint that corresponds to the shape of the side of the head in a wrapped state.
In the impact absorbing structure described in claim 3 , The aforementioned impact-absorbing sheet is a head-whole impact-absorbing sheet in which the area of the human body protected by the spherical cushioning material covers the entire head. The aforementioned head-whole impact absorbing sheet is an impact absorbing structure characterized by having an outer peripheral line joint portion formed by unfolding the three-dimensional shape of the entire head into a planar shape, a polygonal or circular cut line that encloses the unfolded shape of the outer peripheral line joint portion, and a valley fold joint portion formed by folding and joining the remaining fabric portion when the outer peripheral line joint portion is removed from the cut line.
A method for manufacturing an impact-absorbing structure that mitigates external forces, A procedure for selecting a spherical cushioning material that can achieve the target shock absorption performance through a single-layer structure, A procedure for setting a protective area to define the area of human body protection provided by the aforementioned spherical cushioning material, A fabric layering procedure involves preparing multiple pieces of fabric having an area large enough to encompass the aforementioned protective area and layering them together, A storage space formation procedure comprising joining the overlapping fabrics with equally spaced storage lines having a width approximately half the circumference of the selected spherical cushioning material to form multiple rows of storage spaces for the spherical cushioning material, A procedure for inserting spherical cushioning materials, wherein the selected spherical cushioning materials are inserted into each of the multiple rows of storage spaces, and the spherical cushioning materials in adjacent rows are arranged alternately with an approximate radius offset between them, The process includes inserting the spherical cushioning material until the protective area is covered, joining it with the outermost spherical cushioning material along the outermost outermost line, and removing any excess fabric along the cut line , The method for manufacturing an impact-absorbing structure is characterized by performing a pre-impact test or a simulated impact test in which a head impactor having the same rigidity as a human head is free-dropped from a height position according to the JCF safety standard toward a collection of cushioning materials arranged in a single layer, and selecting a cushioning material with a shape and material such that the test results using the three-axis composite acceleration are below the prescribed JCF safety standard .

Description

This invention relates to an impact-absorbing structure and a method for manufacturing an impact-absorbing structure. Conventionally, shock-absorbing structures are known that comprise multiple elastic spheres, which are spherical and elastically deform according to the magnitude and direction of an external force applied from the outside, and a soft bonding structure provided between the elastic spheres, which are arranged in a planar configuration (see Patent Document 1). Furthermore, shock-absorbing structures are known in which multiple rows of spheres, each having a through-hole, are stacked in the direction of the through-hole's penetration, and each sphere is positioned such that the axis of the through-hole of each sphere in the upper layer coincides with the axis of the through-hole of the corresponding sphere in the lower layer (see Patent Document 2). Patent No. 5433642Patent No. 6174431 This shows an example (cross-sectional view) of the application of the top-of-the-head impact-absorbing sheet of Example 1 to a head protection device.This shows a plan view of the head impact absorbing sheet of Example 1.Figure 2 shows a cross-sectional view of the head impact absorbing sheet of Example 1, taken along line I-I.The polystyrene foam sphere selected for the head impact absorption sheet in Example 1 is shown.The test conditions for the hypothetical impact test on the polystyrene foam sphere are shown.This shows a sample of the cushioning material used in the simulated crash test.The results of a hypothetical impact test on a polystyrene foam sphere are shown.The procedure for manufacturing the head impact absorbing sheet of Example 1 is shown below.This diagram illustrates the procedure for creating storage spaces in the sheet manufacturing process.This diagram illustrates the procedure for inserting spherical cushioning material as part of the sheet manufacturing process.This diagram illustrates the finishing steps in the sheet manufacturing process.The table below summarizes the characteristics of hard-type (one-piece molded) head protection.The table below summarizes the features of hard-type (foldable) head protection.The following table summarizes the characteristics of soft-type (layered) head protection devices.The table below summarizes the features of the head protection device incorporating the sheet from Example 1.This shows a sample of a layered spherical buffer material used in a comparative test of a simulated impact test.The results of a comparative test of a foamed sample, a two-layer sample, and a three-layer sample in a hypothetical impact test are shown.A reference diagram illustrating the operation of the head-top impact-absorbing sheet of the invented technology is shown.A reference diagram illustrating the effect of the impact-absorbing sheet on the top of the head, used in comparative technology, is shown.This shows a plan view of the head-side impact-absorbing sheet of Example 2.This shows an external view of the head-side impact-absorbing sheet of Example 2.This shows a perspective view of the head protection device with a built-in head-side impact-absorbing sheet according to Example 2.This shows an external view of the head-to-head impact-absorbing sheet of Example 3.An example of a head protection device incorporating the full-head impact-absorbing sheet of Example 3 is shown.This shows a plan view of the head-to-head impact-absorbing sheet of Example 4-1.This shows an external view of the head-to-head impact-absorbing sheet of Example 4-1.This shows a plan view of the head-to-head impact-absorbing sheet of Example 4-2.This shows an external view of the head-to-head impact-absorbing sheet of Example 4-2.This example shows how to simply insert the top-of-the-head impact-absorbing sheet from Example 1 into the hat body.This example shows a head-to-head impact-absorbing sheet with a chin strap attached. The embodiments for carrying out the impact-absorbing structure and the method for manufacturing the impact-absorbing structure of the present invention are described below based on Examples 1 to 4 shown in the drawings. The impact-absorbing structures manufactured by the methods described in Examples 1 to 4 are head impact-absorbing structures that protect the head of the human body, and are applied as impact-absorbing sheets to soft-type head protection devices worn on the heads of cyclists, kick scooters (small specific mopeds), etc.