PROTECTIVE CAP

Abstract: It is an object of the present invention to provide a protective cap which is excellent in the permeability and ventilating capability, and having a waterproof feature in rainy weather or the like, and having a considerable strength. The protective cap according to the present invention comprises a cap body having an inner layer and an outer layer with a clearance therebetween, a number of air holes are provided in the inner and outer layers so that the air holes in the inner layer are displaced from those in the outer layer, in addition dams are provided around the air holes on a surface of the inner layer facing the outer layer, and a spacers each comprising a vertical wall contacting the inner and outer layers are provided at a center of or in adjacent to the air holes. Also the protective cap according to the present invention comprises a cap body having an inner layer and an outer layer with a clearance therebetween, and concave stripes and convex stripes each extending from the vertex in the radial direction are provided alternately on a surface of the inner layer facing the outer layer with air holes provided in the convex stripes, and on the other hand air holes are formed in the outer layer at positions opposite to the concave stripes on the inner layer.

Description: FIELD OF THE INVENTION The present invention relates to a protective cap worn for protection of the head in construction works, engineering works, and other works. BACKGROUND TECHNOLOGY At a site of various types of work, or in a plant, a worker wears a protective cap on his head for protection against the danger caused by a flying or dropping object or against danger of injuries when the worker falls from a height. But if the protective cap is worn for a long time especially in summer or during hard physical labor, the worker's head perspires. As a result, the work becomes uncomfortable to the worker, and in addition the work efficiency becomes lower. To provide a protective cap with permeability, there has been disclosed a protective cap made from a net or a meshed and porous material molded into a multi-layered structure with the openings arranged alternately in Japanese Utility Model Laid-Open Publication No.143736/ 1985. Also the model described in Japanese Utility Model Laid-Open Publication No.7832/ 1983 provides a protective cap with permeability, and further Japanese Utility Model Laid-Open Publication No.94430/ 1989 discloses an air ventilating device to be placed inside safety and protective elements of a working helmet, a vehicle helmet, safety shoes or the like. However, these protective caps are not waterproof in rainy weather when worn outdoors. Japanese Utility Model Publication No.20108/ 1967 discloses a helmet being permeable and waterproof in rainy weather, but in this model, small holes are provided in a side section of the cap body, so that a flying or falling object may come into the cap body through the holes and also the strength is not sufficient; therefore the model can not achieve the essential object of a helmet to protect a wearer's head. Further, when a worker wearing the cap works in a recumbent posture, rain water comes into the helmet, so that the helmet can not be worn in rainy weather. G 85 17 547 U (D1) discloses a protective cap, in particular for water sport (such as white water rafting) consisting of a outer layer and an inner layer, the inner layer being provided with air channels which extend from the interior of the cap to the air channels going through the outer layer; each air channel is covered by a covering element. The reason for this arrangement of the air channels is to prevent branches and stones from entering the air channels and cause injuries to the head of the bearer. DE 84 26 051 U discloses the naturally ventilated protective helmet for workers which is characterised in that, in the upper portion of the outer layer, in particular on the vertex line and, additionally, in the lower portion of the outer layer, there are ventilating openings of arbitrary shape immediately above the head band provided in the outer layer of the cap. US-A-3,780,382 discloses a hat or cap having an outer crown structure containing a number of spaced apertures, and an inner element or elements located opposite the apertures in a relation shielding the user's head from the sun's rays while at the same time allowing free circulation of air into the interior of the hat or cap and to the user's head. Additional freedom for circulation is provided by supporting the hat or cap on the head at only a few circularly spaced locations, to allow movement of air upwardly into the hat or cap between those locations. DISCLOSURE OF THE INVENTION It is an object of the present invention to provide a protective cap which has an excellent permeability and ventilation, which is waterproof in rainy weather or the like, and which has a considerable strength. According to one aspect of the present invention, there is provided a protective cap comprising a cap body having an inner layer and an outer layer with a clearance therebetween, wherein a number of air holes are provided in the inner and outer layers so that the air holes in the inner layer are displaced from those in the outer layer, characterised in that a dam is provided around each of the air holes in the inner layer on a surface thereof facing the outer layer, and a spacer comprising a vertical wall contacting the inner and outer layers is provided at least adjacent to each of said air holes of the inner layer. According to a second aspect, the invention provides a protective cap comprising a cap body having an inner layer and an outer layer with a clearance therebetween, wherein a number of air holes are provided in the inner and outer layers so that the air holes in the inner layer are displaced from those in the outer layer, characterised in that a spacer comprising a vertical wall having a plurality of air flow holes therein and contacting the inner and outer layers is provided around each of the air holes in said inner layer. Under a third aspect, the invention provides a protective cap comprising a cap body having an inner layer and an outer layer with a clearance therebetween, characterised in that concave strips and convex strips each extending from a vertex of the inner layer in a radial direction are alternately provided on a surface of said inner layer facing said outer layer, air holes are provided in said convex strips, and also air holes are formed in said outer layer at positions opposite to the concave strips on said inner layer. Under a fourth aspect, the present invention relates to a protective cap characterised in that a convex strip having air holes at a vertex of a cap body is formed, a clearance along said convex strip is formed by a cover having air holes and drain holes therein, and the air holes in said convex strip and the air holes in said cover are formed so that they are not overlaid on each other. Preferred embodiments of the present invention are recited in the dependent claims. BRIEF DESCRIPTION OF THE DRAWING Fig. 1 is a side view showing a protective cap with a portion of the cap body removed; Fig. 2 is an enlarged view showing a section of a round air hole provided in an inner layer of the protective cap; Fig. 3 is an embodiment of the protective cap according to the present invention in which the form of a spacer is changed; Fig. 4 is an embodiment of the protective cap according to the present invention in which the form and arrangement of each spacer are changed; Fig. 5 is an enlarged view showing a section around an air hole provided in an outer layer of the protective cap; Fig. 6 is a side view showing a longitudinal cross-section of variants of the dam and the spacer; Fig. 7 is a side view showing an inner layer and an outer layer each constituting a cap body in the state where the inner and outer layers are separated in the vertical direction; Fig. 8 is a flat view showing a cap body formed by setting an outer layer over the inner layer shown in Fig.7; Fig. 9 is a side view showing a longitudinal cross-section of the cap body shown in Fig. 8; Fig. 10 is a side view showing a longitudinal cross-section of a key section in a different embodiment of the cap body according to the present invention; Fig. 11 is a side view showing a longitudinal cross-section of the cap body in a still different embodiment of the present invention; and Fig. 12 is a perspective view showing the cap body 10 and cover 30 in the embodiment shown in Fig. 11 in the state where the cap body 10 and cover 30 are separated in the vertical direction. BEST MODE FOR CARRYING OUT THE INVENTION Next the best mode of the protective cap according to the present invention is described Fig. 1 is a side view showing a protective cap with a portion of the cap body removed. A cap body 10 constituting a main body of the protective cap comprises two layers; an inner layer 10A and an outer layer 10B, and a clearance 12 is provided between the two layers. As a material for the protective cap 10, synthetic resins such as polyester, polypropylene, polyethylene, polycarbonate, and ABS resin may be used. When the strength is important, a material such as iron, steel, aluminium, aluminium alloy, and other high strength alloy may be used, and further a material such as fiber-reinforced plastics, or ceramics may be used, if the purpose of use of the protective cap requires. In this embodiment, the thickness of the clearance 12 is substantially uniform in any portion of the cap body 10. As described later, in the present invention, the clearance 12 mainly functions as a flow path for air, so that it is required to provide a space through which air can flow. For this reason, the thickness of the clearance 12 is in a range from 1 to 20 mm, and more preferably in a range from 3 to 10 mm. A number of air holes 20A, 20B are provided in the inner layer 10A as well as in the outer layer 10B. The air holes 20A, 20B are formed substantially uniformly in the entire inner layers 10A and entire outer layer 10B, and in addition the air holes 20A and air holes 20B are displaced from each other. In the present invention, the air holes 20A and 20B are arranged so that they are not overlaid on each other to prevent a flying or falling object, rain water or the like from coming from the outside of the cap body 10 into inside of the cap body 10, via the air holes 20A, clearance 12, and air holes 20B. In this embodiment, the inside of the inner layer 10 and the outside of the outer layer 10B communicate through the air holes 20A, clearance 12, and air holes 20B, so that external air flows between the inside and the outside of the cap body 10 as shown by the arrows in Fig. 1. The air holes 20A, 20B have the function described above, so that they may be provided over the entire cap body 10, or may be provided in portions of the cap body 10, especially in the upper portion thereof, as described later. Also the air holes 20A, 20B may be arranged either regularly or irregularly. There is no specific restriction on the size of the air holes 20A, 20B, and any size is allowable on the condition that strength of the cap body 10 can be maintained. On the other hand, the larger the diameter of the air holes 20A, 20B, the lighter the cap body 10 is. A form of the air holes 20A, 20B is not limited to a round form as shown in the figure, and also an oval form or a rectangular form is allowable. The size and the form of each of the air holes 20A may be different from those of each of the air holes 20B. Further when the inner layer 10A and/or the outer layer 10B of the cap body 10 may be constructed on a meshed structure, the air holes 20A and air holes 20B can be formed on the cap body 10. However, it is important to arrange the air holes 20A and air holes 20B so that they are not overlaid on each other. A dam 16 is provided in a circular form around the air hole 20A on a side of the inner layer 10A facing the outer layer 10B. Fig. 2 is an enlarged view showing a section around the air hole 20A in the inner layer 10A, and Fig. 2(a) is a flat view showing a state when the outer layer 10B is removed, while Fig. 2(b) is a side view showing a longitudinal cross-section thereof taken along the line b-b in Fig. 2(a) The height of the dam 16 is must only be enough for preventing intrusion of rain water, so that the height is in a range from around 0.1 to 20 mm, and preferably in a range from around 1 to 3 mm. In this embodiment, the dam 16 is erected upward in the vertical direction from the periphery of the air hole 20A, but the form of the dam 16 is not limited to that described above, and for instance, an upper edge section of the vertically erected section may be further bent outward, or the dam 16 itself may be inclined outward or inward against the air hole 20A to prevent intrusion of rain water into the air hole 20A. Provided at a center of the air hole 20A is a spacer 14 comprising a vertical wall 15 contacting the two layers of the inner layer 10A and outer layer 10B. The vertical wall 15 may be provided in a Y form across the dam 16, or may be provided in a cross form across the dam 16 as shown in Fig.3. Also, the dam 16 may be arranged outside of the air hole 20 adjacent thereto. In any of the embodiments described above, the spacer 14 combines the inner layer 10A and outer layer 10B into a unit, and also ensures a flow path for air by keeping the clearance 12 in the appropriate state. For this reason, it is necessary not to clog the air hole 20A with the form and arrangement of the spacer 14, and especially in the embodiment shown in Fig. 4, the vertical walls folded into two portions are provided at positions opposite to each other to insure a flow path 22 for air therebetween. Also the spacer 14 delivers an impact to the outer layer 10B to the inner layer 10A for dispersion of the impact. Accordingly, as shown in the longitudinal side views shown in Fig. 5(a) and Fig.5(b), the clearance 12 may be kept in the appropriate state with the cap body 10 further strengthened by providing spacers 14B also for the air holes 20B in the outer layer 10B as for the air holes 20A. The spacer 14B provided for the air hole 20B may be one comprising the vertical wall 15 contacting both the inner layer 10A and outer layer 10B arranged in a Y form or a cross form, and one or more vertical walls 15 may be provided adjacent to the air hole 20B. The spacer 14B also prevents intrusion of small flying objects through the air hole 20B. In Fig. 5(a) and Fig. 5(b), a reinforcing ring 16B is provided in a circular form around the air hole 20B. In Fig. 5(a), the reinforcing ring 16B having a vertical wall is formed facing the inner layer 10A, so that no projection is generated on a surface of the cap body 10. On the other hand, in Fig. 5(b), the reinforcing ring 16B is formed on an external surface of the outer layer 10B, and not only reinforces the air hole 20B, but also functions as a dam against rain drops. In Fig. 5(b), the reinforcing ring 16B has an inclined wall surface. When the protective cap according to the present invention is used outdoors in rainy weather or the like, rain water comes into the clearance 12 of the protective cap through the air holes 20B in the outer layer 10B, collides with an external surface of the inner layer 10A, and then flows down along this external surface. Because of this feature, rain drops are always blocked by the dams 16 and never get into inside of the air holes 20A. Fig. 6 is a longitudinal cross-sectional view showing variants of the dam 16 and spacer 14. In this embodiment, the dam 16 and spacer 14 are formed in one piece, and a plurality of air flow holes 24 is provided on a wall surface of the vertical wall 15 constituting the spacer 14. The air flow holes 24 are provided in an upper section of a wall surface of the vertical wall 15 so that rain water will never get into the inside. The air hole 24 may have a slit form as shown in Fig. 6(a), or a round form as shown in Fig. 6(b). To form the cap body 10 according to the present invention, the outer layer 10B with the air holes 20B already provided therein is placed over the inner layer 10A with the air holes 20A already provided therein, and the two layers are jointed and integrated with the spacer 14 described above. Next, description is made of a different embodiment of the protective cap according to the present invention with reference to Fig. 7. Fig. 7 is a side view showing the inner layer 10A and outer layer 10B, each constituting the cap body 10 in the state where the two layers are separated from each other in the vertical direction, and a main body of the protective cap comprises the cap body 10. It should be noted that this view does not show a chip strap to prevent falling off, generally used for a protective cap, nor a socalled fit pad or an impact absorbing liner placed inside the cap body 10 for buffering an impact on the cap body 10. Step section 11 is formed in a lower part of the inner layer in the peripheral direction, and when the outer layer 10B is placed over the inner layer 10A, a lower edge rim of the outer layer 10B is engaged with this step section 11. On a surface of the inner layer 10A positioned upward from the step section 11, concave strips 17 and convex strips 18, each extending in the radial direction from the vertex, are alternately formed. The concave strips 17 serve as flow paths for rain water as described above, and are required only to be relatively concave against the convex strips 18, and for instance, strips each having a U-shaped or V-shaped cross-section, or even a flat plane is allowable. The number of concave strips 17 and convex strips 18 is preferably in the range of 10 to 20. A plurality of air holes 20A are provided at appropriate positions on the convex strips 18. The air holes 20A are for flowing air therethrough, and there is no specific restriction on the positions where the air holes 20A are provided. The number of the air holes 20A is preferably in the range of several to several tens in all on the entire inner layer 10A. It should be noted that the dam 16 may be provided in a circular form around the air hole 20A, so that it faces the outer layer 10B as shown in Figs. 2 to 4 as well as in Fig. 6 to prevent intrusion of rain water, and also that the reinforcing ring 16B may be provided around the air hole 20B as shown in Fig. 5. It is required that the outer layer 10B is slightly larger than the inner layer 10A. Also a plurality of air holes 20B are provided in the outer layer 10B. The air holes 20B are provided so that the air holes 20B are not overlaid on the air holes 20A when the outer layer 10B is placed above the inner layer 10A. For this purpose, it is required to provide the air holes 20B at positions opposite to the concave strips 17 on the inner layer 10A. The same conditions for the air holes 20A are required for the size, the number, and the form of each of the air holes 20B. The reference numeral 19 indicates water drain holes provided at several positions in a circular lower edge section of the outer layer 10B, and the drain holes 19 discharge rain water flowing down in the concave strips 17 on the inner layer to the outside of the outer layer 10B. Fig.8 is a flat view showing the cap body 10 formed by placing the outer layer 10B over the inner layer 10A shown in Fig.7, and in this figure two solid lines, each indicating the arrangement of the air holes 20B in the outer layer, and two dotted lines, each indicating arrangement of the air holes 20A in the inner layer 10A, are shown to indicate that the air holes 20A and air holes 20B are displaced from each other. Fig.9 is a side view showing a longitudinal cross-section of the cap body 10 shown in Fig.8, and in the figure, a left half section was cut at a position of the concave strip 17 on the inner layer 10A, while a right half section was cut at a position of the convex strip 18 on the inner layer 10A. The clearance 12 is formed between the two layers 10A, 10B. Preferably thickness of the clearance 12 at the position of concave strip 17 is in a range of around 3 to 30 mm, and that at the position of convex strip 18 is in a range of around 1 to 20 mm. For the purpose to promote integration of the inner layer 10A and outer layers 10B, or to increase strength of the protective cap 10, the spacers 14, 14B described above may be provided in the clearance 12. Also as shown in the right half section of Fig. 9, the convex strips 18 on the inner layer 10A may be contacted partially to the outer layer 10B so that the strips 18 play the role of the spacer 14. When a protective cap according to the present invention is used outdoors in rainy weather or under the same conditions, rain water comes into the clearance 12 of the protective cap through the air holes 20B in the outer layer 10B, and reaches the external surface of the inner layer 10A. Then, the rain water flows down along the concave strips 17 on the inner layer 10A, and is discharged to the outside through the drain holes 19 in the outer layer. Generally a protective cap put on a worker's head is frequently inclined, but as the air holes 20A provided in the inner layer 10A are positioned on the convex strips 18, the rain water does not run into the inside of the inner layer 10A from the air holes 20A. When a protective cap which receives a strong wind pressure on its front section, such as a protective cap for a bicycle rider, the concave strips 17 are not always required to be formed in a radial form from the vertex of the inner layer 10A, and in that case the concave strips 17 are preferably formed into lines so that rain water is smoothly discharged from the front section to the rear section thereof. Next, description is made of a different embodiment of the protective cap of the present invention with reference to Fig. 10. The embodiment shown in Fig. 10 is different from the one described above in that only one convex strip 18 is formed at a vertex of the cap body 10. Fig.10 is a partial side view showing a cross-section of this convex strip 18 along a vertical surface crossing the convex strip 18 at right angles. In this embodiment, the protective cap 10 is not divided into the inner layer 10A and outer layer 10B, and a cover 30 is engaged in the cap body 10 so that the cover 30 covers the convex strip 18 and the concave strips 17, 17 formed along the convex strips 18 at both sides thereof, and the cover 30 is integrated with the cap body 10 by means of ultra-sonic welding or an appropriate bonding method. A plurality of air holes 20B are formed in the cover 30 for the same purpose as that described in the previous embodiment, and the air holes 20B are provided at positions so that they are not overlaid on the air holes 20A provided in the convex strip 18. With the configuration described above, the clearance 12 is formed between a section along the convex strip 18 of the cap body 10 and the cover 30, and also in this embodiment, as in the embodiment shown in Fig. 7 to Fig. 9, measures for permeability and those against rain water are taken. Especially, in the present embodiment, by providing the convex strip 18 in a direction from the front section to the rear section thereof at the vertex of the cap body 10, the air holes 20B can be oriented in a direction from right to left on the cap body 10, so that, even when the cap is used as a protective cap for a bicycle rider, the quantity of rain water coming into the clearance 12 can be minimized. The number of convex strips 18 is not always limited to one, and a plurality of convex strips 18 may be provided in parallel to each other in a direction from the front section to the rear section thereof on the cap body 10. Then, description is made for a still different embodiment of the protective cap according to the present invention with reference to Fig.11 and Fig.12. Fig.12 is a perspective view showing the cap body 10 and the cover 30 in the state where they are separated in the vertical direction, and Fig. 11 is a side view showing a cross-section of a key section cut along a vertical surface crossing the convex strip 18 at right angles. This embodiment is different from the embodiment shown in Fig. 10 in that a spacer 26 contacting the internal wall of the cover 30 and projecting from the concave strip 17 is provided in the clearance 12. The spacer 26 promotes integration of the cover 30 and cap body 10 to improve the strength of the cap body 10, and if the spacer 26 is provided so that it surrounds the air hole 20A, the spacer 20 can also function as a dam for preventing intrusion of rain water. Thus the concave strips 17A and 17B are provided outside and inside the spacer 26 respectively, so that prevention of intrusion of rain water can be achieved more completely. It should be noted that an air hole 28 is provided in an upper wall surface of the spacer 26, as shown in Fig. 12, to flow air therethrough. It should be noted that, in the present invention, a buffering material such as foamed polystyrene or various types of sponge may be provided in the clearance 12. However, the buffering material must have a form not interfering with permeability, ventilation, and the waterproof capability of the protective cap, and also the same considerations must be taken when the buffering material is set in the clearance 12. We conducted, according to the requirements set by the Labor Minister (The official announcement No.39 from Labor Ministry dated on June 5, 1991), the penetration resistance test (Article 6 and Article 7) and shock absorbing test (Article 8) for the all types of protective cap described above, and all the protective caps satisfied the required performance. APPLICABILITY FOR INDUSTRIAL PURPOSES The protective cap according to the present invention is excellent in its permeability and ventilating capability, and can completely prevent intrusion of rain water. Also, when a cap body is constructed on a dual structure, the cap body has especially high strength, is excellent in shock resistance, and has high safety as a protective cap. For the reasons described above, the protective cap according to the present invention can be used in various construction works, in operating a heavy construction machine, in driving a vehicle or an airplane, in guarding works inside or outside a building, in the work of policemen or firemen, and further in playing American football, ice hockey, and other types of sports. Also, the protective cap can be worn at a site of construction works for a building, a dam, or the like, at a site for construction of a road, tunnel, or the like, or at a work shop in a ship mill, an iron foundry, an ironworks, at a mining site, and at sites for various works or in plants.

Claims: A protective cap comprising a cap body (10) having an inner layer (10A) and an outer layer (10B) with a clearance (12) therebetween, wherein a number of air holes (20A, 20B) are provided in the inner (10A) and outer(10B) layers so that the air holes (20A) in the inner layer (10A) are displaced from those (20B) in the outer layer (10B), characterised in that a dam (16) is provided around each of the air holes (20A) in the inner layer (10A) on a surface thereof facing the outer layer (10B), and a spacer (14) comprising a vertical wall (15) contacting the inner (10A) and outer (10B) layers is provided at least adjacent to each of said air holes (20A) of the inner layer (10A). The protective cap according to Claim 1, wherein an additional spacer (14B) comprising a vertical wall (15) contacting the inner (10A) and outer (10B) layers is provided at least adjacent to each of the air holes (20B) in said outer layer (10B). The protective cap according to Claim 1, wherein a reinforcing ring (16B) is provided around each of the air holes (20B) in said outer layer (10B). A protective cap comprising a cap body (10) having an inner layer (10A) and an outer layer (10B) with a clearance (12) therebetween, wherein a number of air holes (20A, 20B) are provided in the inner (10A) and outer (10B) layers so that the air holes (20A) in the inner layer (10A) are displaced from those (20B) in the outer layer (10B), characterised in that a spacer (14) comprising a vertical wall (15) having a plurality of air flow holes (24) therein and contacting the inner (10A) and outer (10B) layers is provided around each of the air holes (20A) in said inner layer (10A). The protective cap according to Claim 4, wherein an additional spacer (14B) comprising a vertical wall (15) contacting the inner (10A) and outer (10B) layers is provided at least adjacent to each of the air holes (20B) in said outer layer (10B). The protective cap according to Claim 4, wherein a reinforcing ring (16B) is provided around each of the air holes (20B) in said outer layer (10B). A protective cap comprising a cap body having an inner layer (10A) and an outer layer (10B) with a clearance (12) therebetween, characterised in that concave strips (17) and convex strips (18) each extending from a vertex of the inner layer (10A) in a radial direction are alternately provided on a surface of said inner layer (10A) facing said outer layer (10B), air holes (20A) are provided in said convex strips (18), and also air holes (20B) are formed in said outer layer (10B) at positions opposite to the concave strips (17) on said inner layer (10A). The protective cap according to Claim 7, wherein a dam (16) is provided around each of the air holes (20A) in said inner layer (10A). The protective cap according to Claim 7, wherein a reinforcing ring (16B) is provided around each of the air holes (20B) in said outer layer (10B). The protective cap according to Claim 7, wherein the convex strips (18) on said inner layer (10A) contact the outer layer (10B) partially. A protective cap characterised in that a convex strip (18) having air holes (20A) at a vertex of a cap body (10) is formed, a clearance (12) along said convex strip (18) is formed by a cover (30) having air holes (20B) and drain holes (19) therein, and the air holes (20A) in said convex strip (18) and the air holes (20B) in said cover (30) are formed so that they are not overlaid on each other. The protective cap according to Claim 11, wherein concave strips (17) are formed along said convex strip (18).

Inventors: SHIRAI SYOJI, SHIRAI, SYOJI, SHIRAI, Syoji Sea Raise Corporation Co., Ltd.
Applicants: BUILMATEL CO LTD, BUILMATEL CO. LTD.
Application year: 1996
Main classification: A42B3
IPC codes: A42B3