Safety helmet

Abstract

A safety helmet capable of forming an inner body in a lightweight and compact manner. The safety helmet is provided with a helmet shell (1) covering a human head and an inner body (2) provided between the helmet shell (1) and the human head. A block-shaped restriction portion (6) is provided between the helmet shell (1) and the human head, and when the helmet shell (1) approaches the human head due to an impact from the outside, only a part of the restriction portion (6) is deformed, and the other part restricts the crown of the helmet shell from approaching the human head.

Description

Technical Field

[0001] This invention relates to safety helmets. Background Technology

[0002] The safety helmet comprises a helmet shell and an inner body disposed inside the helmet shell. The helmet shell is made of a rigid synthetic resin material or the like and covers and protects the human head from the outside. The inner body includes a liner and a headband. The liner contacts the human head, forming a gap between the human head and the inner surface of the helmet. The headband is attached to and secured to the outer periphery of the human head at the lower end of the liner. Furthermore, the inner body also includes a chin strap for maintaining the wearing position and impact-absorbing pads for absorbing impact (see, for example, Patent Document 1).

[0003] However, helmets with shock-absorbing pads can cause internal heat buildup and stuffiness, compromising wearing comfort.

[0004] In addition, in recent years, a type of helmet has been known that does not have an impact-absorbing liner but instead uses an inner body to absorb impact and ensure ventilation and heat dissipation inside the helmet (for example, see Patent Document 2). This prevents heat buildup and stuffiness inside the helmet.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 8-311713

[0008] Patent Document 2: Japanese Patent Application Publication No. 2017-133124 Summary of the Invention

[0009] The problem that the invention aims to solve

[0010] However, the safety helmets described above require the inner body to absorb a portion of the impact from the shell, especially the foot section of the liner that contacts the head, which needs sufficient strength. Therefore, it is difficult to reduce the amount of resin material forming the foot section, resulting in a heavy helmet that becomes a burden for the wearer. Furthermore, it is impossible to form the inner body compactly, resulting in the top of the helmet shell being significantly higher than the top of the head when worn.

[0011] In view of the above problems, the object of the present invention is to provide a safety helmet that can be formed into an internal body in a lightweight and compact manner.

[0012] Methods for solving problems

[0013] To achieve the above objectives, the technical content of the safety helmet of the present invention is as follows. The safety helmet has a shell covering the human head and an inner body disposed between the shell and the human head. The safety helmet is characterized in that a block-shaped restricting part is provided between the shell and the human head. When the shell approaches the human head due to an external impact, only a portion of the restricting part deforms, while the other portion restricts the shell from approaching the top of the human head.

[0014] By providing a limiting part, the cap shell can be prevented from approaching the human head, thereby preventing contact between the cap shell and the human head, and thus reducing the burden on the inner body. Therefore, according to the present invention, materials such as synthetic resin used to form the inner body can be reduced, and the inner body can be made lighter.

[0015] Furthermore, due to the presence of the limiting part, the distance between the top of the human head and the inner surface of the helmet shell can be reduced, thus allowing the height of the head to be controlled at a low level when wearing a helmet, thereby achieving a compact helmet shell.

[0016] Furthermore, in this invention, the limiting portion is characterized in that at least a portion of the limiting portion contacts the cap shell when the top of the cap shell is deformed inward, and the limiting portion is configured to buckle and deform in response to the deformation of the cap shell.

[0017] When an impact load is applied to the top of the helmet shell, the top of the shell deforms in a concave manner, thereby resisting the applied impact load. Preferably, a portion of the restraining part contacts the concave deformed portion of the top of the shell and is compressed and deformed, but the other portions of the restraining part (the portions that do not undergo buckling deformation) maintain their original shape, thus limiting the concave deformation of the helmet shell to closely resemble the human head.

[0018] In addition, in this invention, it is preferred that the limiting part has a base end face located on the side of the human head and a top end face opposite to the inner surface of the cap shell, the length from the base end face to the top end face is set to 15mm to 25mm, and the diameter of the circumscribed circle of the top end face is set to 10mm to 50mm.

[0019] The length of the limiting part from the base end face to the top end face is 15mm to 25mm, and the diameter of the circumscribed circle of the top end face is 10mm to 50mm. Thus, the approach of the human head to the cap shell can be reliably limited with the required minimum size.

[0020] Furthermore, in this invention, it is preferable that the limiting part is configured to require a load of at least 500N to achieve a strength of 2mm deformation during compression.

[0021] To prevent the deformed cap from approaching the human head, the limiting part needs to have a specified level of hardness (compressive strength). Therefore, the limiting part is designed to withstand a load of at least 500 N to achieve a deformation of 2 mm under compression. This reliably prevents the deformed cap from approaching the human head.

[0022] Furthermore, in this invention, the limiting portion is characterized by having one or more cylindrical bodies, and more preferably, the limiting portion has a honeycomb shape formed by a plurality of hexagonal cylindrical bodies.

[0023] By configuring the aforementioned restrictive portion as a cylindrical body, a flexible restrictive effect based on buckling deformation can be obtained. In particular, by forming the restrictive portion into a honeycomb shape consisting of multiple hexagonal cylindrical bodies, a structure can be formed in which the buckling strength increases in stages from the outermost peripheral wall side to the inward side. Therefore, the approach of the cap shell to the human head is mitigated by the deformation of the restrictive portion, further reducing the burden on the human head. Attached Figure Description

[0024] Figure 1 This is an explanatory diagram of a safety helmet according to an embodiment of the present invention.

[0025] Figure 2 It is a three-dimensional image displayed with the hat liner unfolded.

[0026] Figure 3 This is a side view used to illustrate the feet.

[0027] Figure 4 This is a cross-sectional view used to illustrate the connection part that connects to the cap.

[0028] Figure 5 It is a plan view used to illustrate the connecting parts.

[0029] Figure 6A It is a three-dimensional diagram used to illustrate the limiting part.

[0030] Figure 6B It is a plan view used to explain the limiting part.

[0031] Figure 7 This is an explanatory diagram showing the function of the limiting part.

[0032] Figure 8 This is a table indicating the strength of the limiting part. Detailed Implementation

[0033] One embodiment of the present invention will be described with reference to the accompanying drawings. For example... Figure 1As shown, the helmet of this embodiment includes a shell 1 formed into a dome shape by means of a rigid material. A liner 2 is disposed inside the shell 1. The liner 2 constitutes an inner body. In addition to the liner 2, the inner body also includes a top strap 3, a chin strap (not shown), etc.

[0034] The cap liner 2 is formed by injection molding using a synthetic resin (e.g., low-density polyethylene). For example... Figure 2 As shown, the cap liner 2 includes: a head ring 4; a plurality of (four in this embodiment) foot portions 5; a limiting portion 6 connected to the head ring 4; and an impact-absorbing portion 7 disposed between adjacent foot portions 5.

[0035] Additionally, a top strap connecting piece 8 is provided on one side edge (front side edge) of the foot 5 to connect to the top strap 3, and a jaw strap connecting piece 9 is provided on the other side edge (rear side edge) of the foot 5 to connect to the jaw strap (not shown).

[0036] The head-mounted ring portion 4 is formed into a generally elliptical shape that is elongated along the front-to-back direction. A protrusion 10 is provided on the inner side of the head-mounted ring portion 4. The protrusion 10 expands the contact area between the head-mounted ring portion 4 and the human head, improving wearing comfort. It should be noted that, in this embodiment, to achieve weight reduction, a through hole 11 is formed along the shape of the protrusion 10.

[0037] Each foot 5 is formed into a band, and its upper end is connected to the ring-shaped part 4 on the top of the head. A connecting part 12 is provided at the lower end (top) of each foot 5.

[0038] In addition, a plurality of protrusions 13 and 14 (two in this embodiment) are formed on each foot 5. In the foot 5, the protrusions 13 and 14 are provided as thick-walled portions, and the other portions except for the protrusions 13 and 14 and the connecting portion 12 are provided as thin-walled portions 15.

[0039] The thin-walled portion 15 has high flexibility, while the convex portions 13 and 14 have low flexibility. Therefore, when the foot 5 bends along the human head, as... Figure 3 As shown, different local curvatures result in parts that come into contact with the human head and parts that do not (or parts that make strong contact with the human head and parts that make light contact).

[0040] When the foot 5 contacts the human head, a smaller foot 5 allows for a lighter cap liner 2 compared to a larger one. However, when the narrow foot 5 contacts the human head, the load of the cap shell 1 is applied to the human head in a continuous linear manner (e.g., creating a feeling of being sunk into the skin), reducing the wearing comfort.

[0041] At this time, by forming a thin-walled part 15 with high flexibility and a protrusion 13, 14 with low flexibility on the foot 5, the foot 5 intermittently contacts the human head. Compared with the case where the load of the cap 1 is applied to the human head in a continuous linear manner, the feeling of sinking into the skin can be reduced, and thus the reduction in wearing comfort can be suppressed.

[0042] Furthermore, the cap liner 2 is formed using a synthetic resin material and injection molding. In this injection molding, the portion of the mold corresponding to the foot 5 is relatively long and narrow. When the molten resin flows inside such a long and narrow mold, molding defects are easily generated due to flow resistance, etc. However, the portion of the mold corresponding to the protrusions 13 and 14 (thick-walled portions) becomes a place where molten resin accumulates. Therefore, the distance between the narrower portion of the mold corresponding to the foot 5 is substantially shortened, thereby preventing molding defects.

[0043] Furthermore, the protrusions 13 and 14 of the foot 5 form a gap between the foot 5 and the cap 1. Thus, the protrusion 13, which is closest to the connecting part 12 among the multiple protrusions 13 and 14, functions as a finger hook.

[0044] A rivet-like portion 16 (locking portion) is provided on the inner surface of the cap shell 1 to lock the connecting portion 12 when the foot 5 is connected. For example... Figure 4 As shown, the rivet-like part 16 has a rivet shaft 16a protruding into the inner surface of the cap 1 and a disc-shaped rivet head 16b with an expanded diameter at the top of the rivet shaft 16a.

[0045] like Figure 2 and Figure 5 As shown, a large-diameter opening 12a and a small-diameter opening 12b are formed adjacently and continuously on the connecting portion 12. The large-diameter opening 12a is large enough to allow the rivet-like portion 16 to pass through freely. The rivet-like portion 16 cannot pass through the small-diameter opening 12b, which is approximately the same size as the outer diameter of the rivet shaft 16a. The small-diameter opening 12b is formed at a position below the large-diameter opening 12a (on the top end side of the foot 5).

[0046] When connecting the foot 5 to the cap 1, the rivet head 16b of the rivet-shaped part 16 passes through the large-diameter opening 12a of the connecting part 12. Then, the connecting part 12 is slid along the inner surface of the cap 1 toward the top of the cap 1, so that the rivet shaft 16a is embedded in the small-diameter opening 12b.

[0047] When the foot 5 is removed from the cap 1, the connecting part 12 slides along the inner surface of the cap 1 toward the lower edge of the cap 1, so that the rivet shaft 16a of the rivet-like part 16 moves relative to the large diameter opening 12a from the small diameter opening 12b.

[0048] At this time, by hooking the fingers to Figure 3The protrusion 13 (finger hook portion) of the foot 5 shown can reliably perform the sliding operation of the connecting portion 12, and can smoothly release the engagement between the rivet shaft 16a and the small diameter opening 12b even when the rivet shaft 16a is firmly embedded in the small diameter opening 12b.

[0049] Therefore, by pulling the rivet head 16b of the rivet-shaped part 16, which has moved to the large diameter opening 12a, out of the large diameter opening 12a, the foot part 5 can be removed from the cap 1.

[0050] It should be noted that, as Figure 5 As shown, by providing a guide mark 17 (marker) at the protrusion 13 (finger hook portion) to indicate the sliding direction during disassembly, it is not only easy to visually confirm the sliding operation direction during disassembly, but also easy to determine the position of the finger hook at the protrusion 13 (finger hook portion).

[0051] It should be noted that, in this embodiment, as Figure 2 As shown, by providing top strap connecting pieces 8 and jaw strap connecting pieces 9 on both sides of the foot 5, they can also be used as finger hooks. That is, by hooking fingers onto the top strap connecting pieces 8 and jaw strap connecting pieces 9, the connecting part 12 can slide along the inner surface of the cap 1 toward the lower edge of the cap 1, making it easy to remove the foot 5 from the cap 1.

[0052] Next, the impact absorption section 7 will be described. The impact absorption section 7 is provided at four positions: front, rear, left, and right. Among them, the left and right impact absorption sections 7 are connected to the limiting section 6.

[0053] like Figure 2 As shown, a pair of limiting parts 6 are provided at a position slightly forward of the top of the head and offset to the left and right sides from the top of the head. Figure 6A As shown in the perspective view, the limiting part 6 includes a limiting part body 61 and a limiting part support part 62 that supports the limiting part body 61. The limiting part support part 62 is integrally formed with the top annular part 4 to form the base end face of the limiting part 6. The limiting part support part 62 supports the impact absorbing parts 7 on the left and right sides via an extension part 63.

[0054] The main body 61 of the limiting part has a honeycomb shape formed by assembling multiple hexagonal cylindrical bodies 61a, with its top surface 61b facing the inner surface of the cap 1. By forming the cylindrical bodies 61a into hexagonal cylindrical shapes, a honeycomb-shaped limiting part 61 can be constructed in which adjacent cylindrical bodies 61a share peripheral walls.

[0055] In addition, the main body 61 of the limiting part has a structure with multiple cylindrical bodies 61a, thereby forming a structure in which the buckling strength increases in stages from the peripheral wall side to the inward side of the main body 61 of the limiting part.

[0056] That is, such as Figure 7As shown, when the top of the cap 1 is subjected to an impact load, the top of the cap 1 undergoes a concave deformation, reducing the distance between the inner surface of the cap 1 and the human head. Correspondingly, the limiting body 61, which is pressed against the cap 1, undergoes buckling deformation at a portion of its upper peripheral corner. On the other hand, almost no buckling deformation occurs in other parts of the limiting body 61, thus limiting the cap 1's approach to the human head and preventing contact between the cap 1 and the human head.

[0057] Furthermore, the length L of the limiting part 6 from the limiting part support part 62 constituting the base end face to the top end face 61b is 20 mm. It should be noted that it is preferable to set this length L in the range of 15 mm to 25 mm.

[0058] Setting the length L from the restrictor support 62 to the top surface 61b within the range of 15mm to 25mm is based on insights gained by the inventors through various experiments. According to this insight, if the length L is greater than 25mm, the gap between the helmet shell 1 used to house the restrictor 6 and the human head must be increased. Therefore, the height of the helmet when worn (the top of the helmet shell 1) becomes extremely high relative to the position of the human head, potentially impairing the fit and stability when wearing the helmet. Furthermore, if the length L is less than 15mm, the restrictor body 61 is difficult to bend or deform, or, if the helmet shell 1 deforms due to impact, the distance between the helmet shell 1 and the human head cannot be adequately ensured.

[0059] Therefore, by setting the length L of the limiting part 6 from the limiting part support part 62 to the top surface 61b within the range of 15mm to 25mm, the height of the helmet when worn can be suppressed and the limiting part 6 can be housed in the gap formed between the human head and the helmet shell 1. Furthermore, when the limiting part 6 is pressed by the concave deformation of the helmet shell 1, the limiting part 6 can be bent while the helmet shell 1 is reliably restricted to a position that does not contact the human head.

[0060] Moreover, such as Figure 6B The planar shape of the top surface 6lb of the limiting part body 61 shown is illustrated, and the diameter R of the circumscribed circle W (imaginary line) of the top surface 6lb of the limiting part 6 is 30mm. It should be noted that the diameter R of the circumscribed circle W is preferably set in the range of 10mm to 50mm.

[0061] Setting the diameter R of the circumcircle W of the top surface 61b within the range of 10mm to 50mm is based on insights gained by the inventors through various experiments. According to this insight, a diameter R greater than 50mm causes the limiting portion 6 to become unnecessarily large when the helmet shell 1 approaches the human head, resulting in an undesirable situation that hinders the lightweighting of the helmet. Furthermore, if the diameter R is less than 10mm, the limiting portion body 61 may tip over before buckling and deforming, failing to exert the limiting force required to prevent the helmet shell 1 from approaching the human head.

[0062] Therefore, by setting the diameter R of the circumcircle W of the top surface 61b of the limiting part 6 within the range of 10mm to 50mm, the limiting part 6 can be made as small as possible to achieve weight reduction. Moreover, when the limiting part 6 is pressed by the concave deformation of the cap 1, it will not tip over but will reliably buckle, thereby exerting sufficient limiting force.

[0063] Therefore, when the limiting part 6 is compressed by the cap 1, it produces the following: Figure 7 The buckling deformation is shown. In this embodiment, the limiting part 6 is set to require a load of at least 500N to achieve a strength where the deformation during compression is 2mm.

[0064] Figure 7 The diagram shown is a schematic representation of an experiment conducted by the inventors to confirm the limiting effect of the limiting part 6. In this experiment, it was confirmed that the limiting part 6 could not exert sufficient limiting force at a strength where it would produce a buckling deformation of 2 mm under a load of less than 500 N. Therefore, by setting the limiting part 6 to a strength requiring a load of at least 500 N to achieve a deformation of 2 mm upon compression, sufficient limiting force can be obtained, thereby reliably preventing the cap 1 from approaching the human head.

[0065] Furthermore, the inventors confirmed the strength of the restrictor 6 through compression performance tests. Specifically, loads were applied to the entire surface, half surface, and 2 / 7 surface of the upper end face of the restrictor 6, and the applied loads were measured as strength when 2 mm of deformation and 10 mm of deformation occurred. As a result, it was confirmed that the preferred strength of the restrictor 6 used in this embodiment is [insert strength here]. Figure 8 The intensity shown.

[0066] As described above, by utilizing the limiting part body 61 of the limiting part 6, it is possible to prevent the cap shell 1 from contacting the human head, thereby greatly reducing the burden on the foot 5 of the cap liner 2. Therefore, the foot 5 can be made thinner or narrower, thus reducing the amount of synthetic resin material used and achieving cost reduction and weight reduction of the cap liner 2.

[0067] Furthermore, by utilizing the limiting effect of the limiting part 6, the distance (space volume) between the top of the human head and the inner surface of the top of the helmet shell 1 can be reduced, thus the height of the helmet shell 1 can be controlled to a smaller size, achieving a compact helmet.

[0068] In addition, such as Figure 6A As shown, the limiting support 62 is formed in the shape of a plate and closes the bottom of the limiting body 61. For example, the cylindrical body 61a of the limiting body 61 does not directly contact the human head, thus preventing a decrease in wearing comfort.

[0069] Based on the above structure, by appropriately setting the wall thickness of the peripheral wall of each cylindrical body 61a constituting the main body 61 of the limiting part, the number of cylindrical bodies 61a (the cylindrical body of the limiting part in this invention can be one or more), the height of the cylindrical body 61a, and the diameter of the cylindrical body 61a, the crushing speed and crushing shape of the limiting part 6 being crushed by the pressure received from the cap 1 can be easily adjusted.

[0070] Furthermore, in this embodiment, an example is shown where the limiting part 6 and the cap liner 2 are integrally provided, but the limiting part of the present invention may also be provided separately from the cap liner. Specifically, although not shown, for example, a support part may be provided between the cap liner and the cap shell, and the limiting part may be provided on the support part.

[0071] Industrial availability

[0072] According to the present invention, it is possible to provide a lightweight and compact helmet with a comfortable wearing experience.

[0073] Symbol Explanation

[0074] 1…cap shell, 2…cap liner (inner body), 3…top strap (inner body), 4…top ring, 5…foot, 6…restriction part, 7…impact-absorbing part, 8…headband connecting piece, 9…jaw strap connecting piece, 10…protrusion, 11…through hole, 12…connecting part, 13, 14…protrusion (thick-walled part), 15…thin-walled part, 13…protrusion (finger hook part), 16…riveting part (locking part), 16a…riveting shaft, 16b…riveting head, 12a…large diameter opening, 12b…small diameter opening, 17…guide mark (identification part), 61…restriction part body, 62…restriction part support part, 63…extension, 61a…cylindrical body.

Claims

1. A safety helmet comprising a shell covering a human head and an inner body disposed between the shell and the human head. The safety helmet is characterized in that... The inner body has a block-shaped restrictive portion disposed between the cap shell and the human head. When the cap shell approaches the human head due to an external impact, only a portion of the restrictive portion deforms, while the other portion prevents the cap shell from approaching the top of the human head. A pair of limiting parts are provided at a position slightly forward of the top of the head and offset to the left and right sides from the top of the head. Each limiting part has a limiting part body and a limiting part support part that supports the limiting part body. The main body of the restricting part has a honeycomb shape composed of multiple hexagonal cylindrical bodies, with its top surface facing the inner surface of the cap shell, thus forming a structure with multiple cylindrical bodies. This results in a structure where the buckling strength increases in stages from the peripheral wall side to the inward side of the main body of the restricting part. When the top of the cap is subjected to an impact load and the cap deforms inward, the main body of the limiting part pressed by the cap undergoes buckling deformation at a portion of the peripheral corner of its upper end.

2. The safety helmet according to claim 1, characterized in that, The main body of the limiting part is disposed at a position where at least a portion of the limiting part contacts the cap shell when the top of the cap shell is concave and deformed, and is configured such that a portion of the limiting part undergoes buckling deformation in response to the deformation of the cap shell.

3. The safety helmet according to claim 1 or 2, characterized in that, The limiting part support and the top ring part are integrated to form the base end face of the limiting part. The main body of the limiting part has a honeycomb shape composed of multiple hexagonal cylindrical bodies. Its top end face is opposite to the inner surface of the cap shell. The length from the base end face to the top end face is set to 15mm to 25mm. The diameter of the circumscribed circle of the top end face is set to 10mm to 50mm.

4. The safety helmet according to claim 1 or 2, characterized in that, The main body of the limiting part is formed to have a strength that requires a load of at least 500N to achieve a deformation of 2mm when compressed.

Images