WO2023063057A1 - Impact-absorbing member - Google Patents

Impact-absorbing member Download PDF

Info

Publication number
WO2023063057A1
WO2023063057A1 PCT/JP2022/035617 JP2022035617W WO2023063057A1 WO 2023063057 A1 WO2023063057 A1 WO 2023063057A1 JP 2022035617 W JP2022035617 W JP 2022035617W WO 2023063057 A1 WO2023063057 A1 WO 2023063057A1
Authority
WO
WIPO (PCT)
Prior art keywords
absorbing member
plate
thermoplastic resin
inorganic fibers
impact
Prior art date
Application number
PCT/JP2022/035617
Other languages
French (fr)
Japanese (ja)
Inventor
圭祐 坂口
Original Assignee
東洋紡株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 東洋紡株式会社 filed Critical 東洋紡株式会社
Publication of WO2023063057A1 publication Critical patent/WO2023063057A1/en

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/06—Fibrous reinforcements only
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/06—Fibrous reinforcements only
    • B29C70/10—Fibrous reinforcements only characterised by the structure of fibrous reinforcements, e.g. hollow fibres
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/28—Shaping operations therefor
    • B29C70/30—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
    • B60R19/00—Wheel guards; Radiator guards, e.g. grilles; Obstruction removers; Fittings damping bouncing force in collisions
    • B60R19/02—Bumpers, i.e. impact receiving or absorbing members for protecting vehicles or fending off blows from other vehicles or objects
    • B60R19/18—Bumpers, i.e. impact receiving or absorbing members for protecting vehicles or fending off blows from other vehicles or objects characterised by the cross-section; Means within the bumper to absorb impact
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F7/00—Vibration-dampers; Shock-absorbers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F7/00—Vibration-dampers; Shock-absorbers
    • F16F7/12—Vibration-dampers; Shock-absorbers using plastic deformation of members

Definitions

  • the present invention relates to shock absorbing members.
  • shock absorbing members that absorb collision energy have been arranged.
  • impact absorbing members such as front side members and rear side members are arranged in locations where impacts are expected to be applied to the vehicle.
  • collision energy is applied in the axial direction, which is the direction in which collision energy can be efficiently absorbed, and when the magnitude of the collision energy exceeds the yield stress, the shock absorbing member deforms and absorbs the shock.
  • shock absorbing members It is important for shock absorbing members to absorb impact energy sufficiently and efficiently, and shock absorbing members are often manufactured using metal such as steel plate.
  • Patent Document 1 discloses an automotive collision energy absorbing component that is a cylindrical member, and a metal plate such as a steel plate is used for the cylindrical member.
  • the cylindrical member is formed by spot-welding a hat-shaped member having a top plate portion, a vertical wall portion, a flange portion, and a flat plate-shaped member at the flange portion. It is disclosed that the collision energy is efficiently absorbed when the .
  • Patent Document 1 Although the absorbing member of Patent Document 1 can absorb collision energy, it is difficult to say that it is lightweight because it uses metal plates such as steel plates. In recent years, while high collision safety is required, there is also a demand for weight reduction of shock absorbing members to improve fuel efficiency. There was a limit to trying to
  • Patent Document 2 discloses a fiber-reinforced plastic energy absorbing portion having a cylindrical cross section made of reinforcing fibers and resin, and a support connected to the fiber-reinforced plastic energy absorbing portion and formed of fiber-reinforced plastic and joined to a vehicle body part.
  • a front side member consisting of a part is disclosed, and an energy absorbing member is formed by a method of sheet winding a continuous fiber sheet impregnated with a thermosetting resin or by preforming a woven fabric of reinforcing fibers and performing an RTM method is described.
  • Patent Document 3 discloses, as an energy absorbing member, a fiber-reinforced resin hollow cylindrical body composed of reinforcing fiber threads and a resin composition impregnated in the reinforcing fiber threads, and the hollow cylindrical body is composed of filaments. It is disclosed to be formed by a winding method.
  • Patent Document 4 discloses a vehicle shock absorbing member having a cylindrical portion and a top surface portion formed to block one opening in the axial direction. , the impact energy is absorbed by compression deformation in the axial direction due to the impact load input to the top surface.
  • reinforcing fibers are present as continuous fibers in the absorbent members of Patent Documents 2 and 3, the molding cost is high and the shape that can be molded is limited due to poor moldability. It was difficult to make the impact absorbing member into a complicated shape as shown in FIGS. 1 and 2, which will be described later.
  • the shock absorbing member of Patent Document 4 at least one rib for supporting the load at the time of impact is provided inside the cylindrical portion, connected to the top surface portion and spaced apart from the cylindrical portion. Since it has a special shape, there is a problem that the shape of the shock absorbing member is limited. In addition, since the shock absorbing member of Patent Document 4 is assumed to be formed by injection molding, it is difficult to increase the energy absorption amount of the shock absorbing member when the material breaks, and the shock absorbing property becomes low. I had a problem with it.
  • An object of the present invention is to provide an impact absorbing member whose shape can be set relatively freely, which is lightweight, and which has high collision safety.
  • the inventors of the present invention provided a shock absorbing member having a plate-like member formed by laminating thermoplastic resin tapes containing inorganic fibers, and the orientation of the inorganic fibers in the plate-like member.
  • the inventors have found a shock absorbing member that achieves weight reduction and high collision safety by controlling the weight so as to satisfy predetermined conditions, and arrived at the present invention.
  • the present invention consists of the following configurations.
  • a shock absorbing member having one or more plate-like members, wherein at least one of the plate-like members is formed by laminating thermoplastic resin tapes containing inorganic fibers, and the inorganic fibers In the plate-shaped member comprising the A shock absorbing member characterized by comprising 30 to 60% by volume of the plate member.
  • the impact absorbing member according to [1] above, wherein the inorganic fibers include at least one of glass fibers and carbon fibers.
  • the impact absorbing member according to [1] or [2], wherein the inorganic fibers have an average fiber length of 10 to 150 mm.
  • thermoplastic resin tape has a length of 10 mm to 100 mm, a width of 5 mm to 50 mm, and a thickness of 0.05 mm to 0.3 mm.
  • a shock absorbing member having a tubular portion and a bottom portion, wherein the tubular portion and the bottom portion are composed of the plate-shaped member, and the bottom portion is formed on one side of the tubular portion.
  • a shock absorbing member having a plate-shaped member formed by laminating thermoplastic resin tapes containing inorganic fibers, and controlling the orientation of the inorganic fibers in the plate-shaped member so as to satisfy a predetermined condition, thereby reducing the weight.
  • the impact absorbing member of the present invention has excellent moldability and can be shaped relatively freely. Therefore, it can be used not only for impact absorbing devices for passenger cars, but also for vehicles other than passenger cars and various structures. can be used.
  • FIG. 1 is a perspective view of a shock absorbing member according to an embodiment of the invention
  • FIG. FIG. 4 is a perspective view of a modification of the shock absorbing member according to the embodiment of the invention
  • FIG. 11 is a perspective view of a further modified example of the shock absorbing member according to the embodiment of the present invention
  • FIG. 2 is a bottom view of the shock absorbing member of FIG. 1;
  • the shock absorbing member of the present invention has one or more plate-shaped members.
  • the term “plate-shaped member” refers not only to planar members, but also to bent shapes such as corrugated plates, cylinders, semi-cylindrical shapes, hemispherical shapes, and folded shapes such as zigzag shapes. and the like, and may be a part of these shapes or a combination of these shapes.
  • At least one of the plate-like members is formed by laminating thermoplastic resin tapes containing inorganic fibers, and in the plate-like member containing inorganic fibers, the inorganic fibers are the plate-like member. It is oriented in the direction perpendicular to the thickness direction, and the orientation in the plane along the perpendicular direction is random.
  • a plate-shaped member that is oriented and whose orientation in the plane along the vertical direction is random is referred to as a 'predetermined plate-shaped member'.
  • the inorganic fibers are oriented in a direction perpendicular to the thickness direction, so it exhibits excellent collision safety.
  • shock absorbing member of the present invention having a predetermined plate-shaped member is excellent in shock absorbing property (collision safety) will be explained below. , and problems in the case where the impact absorbing member is molded by the conventional method using the thermoplastic resin.
  • the shock absorbing member cannot stably absorb the collision energy because it will be broken in such a way that the entire body will break. Therefore, the metal shock absorbing member is designed so that when collision energy is applied, it locally buckles while the overall collapse progresses in a bellows-like manner.
  • a shock absorbing member is molded using a thermoplastic resin containing inorganic fibers, if it is designed so that it will break in the same manner as a metal shock absorbing member, the elongation of the thermoplastic resin is small, so the metal Brittle fracture occurs instead of ductile fracture like the impact absorbing member.
  • the impact load applied to the impact-absorbing member fluctuates greatly while the impact-absorbing member is broken. There was a risk of it becoming uncut.
  • the shock absorbing member of the present invention has a predetermined plate-like member, and inorganic fibers are oriented in a direction perpendicular to the thickness direction in the predetermined plate-like member.
  • the plate-shaped member breaks in the direction perpendicular to the direction of orientation of the inorganic fibers, resulting in excellent impact absorption. show gender.
  • the reason why the above-mentioned breaking behavior occurs is that the predetermined plate-like member is close to a state in which a plurality of thermoplastic resin layers containing inorganic fibers are laminated, and when collision energy is applied to the predetermined plate-like member, the interlayer breaks down.
  • the direction perpendicular to the thickness direction of the plate-like member does not have to be strictly perpendicular to the inorganic fibers in the given plate-like member.
  • the average orientation angle of the inorganic fibers with respect to a plane perpendicular to the thickness direction is preferably 0 to 20°.
  • the average orientation angle of the inorganic fibers with respect to the plane perpendicular to the thickness direction is preferably 0 to 35° in the central portion in the axial direction of the cylindrical portion. A method for measuring the average orientation angle will be described later.
  • the “axial direction” refers to the direction in which the shock absorbing member is compressed and deformed by the shock load.
  • the inorganic fibers are randomly oriented in the plane along the direction perpendicular to the thickness direction of the plate-like member.
  • the term “in-plane orientation is random orientation” means pseudo-isotropy, and the in-plane orientation parameter (cos 2 ⁇ y/cos 2 ⁇ x) of the inorganic fibers along the direction perpendicular to the thickness direction of the plate member is preferably greater than 0.67 and less than 1.5, more preferably 0.75 or more and 1.33 or less.
  • the in-plane orientation parameter is 1, it means that the carbon fibers are completely randomly oriented in the in-plane direction. Randomness is impaired, and as a result, there is a risk that impact absorption will be reduced.
  • the in-plane orientation parameter is measured as follows, and the plate-like members (bottom portion and cylindrical portion of the shock absorbing member) used in the examples described later all have an in-plane orientation parameter of greater than 0.67. is smaller than 1.5.
  • the in-plane orientation parameter is obtained by calculating cos 2 ⁇ x and cos 2 ⁇ y for each inorganic fiber, and dividing the average value of cos 2 ⁇ y by the average value of cos 2 ⁇ x to obtain the in-plane orientation parameter (cos 2 ⁇ y/ cos 2 ⁇ x).
  • ⁇ In-plane orientation parameter measurement method Five test pieces of about 15 mm ⁇ 25 mm were cut out from the plate member, and three-dimensional X-ray CT measurement was performed on each test piece. Orthogonal coordinates are determined so that the in-plane direction of the plate-like member is the X-axis and the Y-axis, and the plate thickness direction is the Z-axis. was cut out. Using a three-dimensional measurement X-ray CT device (TDM1000-IS) manufactured by Yamato Scientific Co., Ltd., under the conditions of an acceleration voltage of 40 to 60 kV, a tube current of 10 to 40 ⁇ A, and an integration time of 0.5 to 1 second, the temperature is 0.5 degrees or more.
  • TDM1000-IS three-dimensional measurement X-ray CT device manufactured by Yamato Scientific Co., Ltd.
  • the thermoplastic resin tape preferably has a length of 10 to 100 mm, more preferably 20 to 50 mm. If the length is less than 10 mm, it may be difficult to develop the above-described delamination, and if it exceeds 100 mm, the fluidity during molding may deteriorate.
  • the width of the thermoplastic resin tape is preferably 5 to 50 mm, more preferably 10 to 40 mm. If the width is out of the above range, the production efficiency may deteriorate.
  • the thickness of the thermoplastic resin tape is preferably 0.05-0.3 mm, more preferably 0.07-0.2 mm. If the thickness is less than 0.05 mm, production efficiency may deteriorate, and if it exceeds 0.3 mm, impregnation of the inorganic fibers with the thermoplastic resin may become insufficient.
  • the thermoplastic resin is not particularly limited, and examples include polyamide resins such as nylon 6, nylon 11, nylon 66, and nylon 46; polyester resins such as polyethylene terephthalate and polybutylene terephthalate; polyolefin resins such as polyethylene and polypropylene. polyether ketone resins; polyphenylene sulfide resins; polyetherimide resins; and polycarbonate resins.
  • modified resins of the resins exemplified above may be used.
  • One kind of thermoplastic resin may be used, or two or more kinds thereof may be contained.
  • the modified material of the thermoplastic resin may be, for example, an acid modified material.
  • the acid-modified thermoplastic resin has an acid-modified group introduced therein.
  • the type of acid-modifying group is not particularly limited, and only one type of acid-modifying group may be included, or two or more types may be included. —COOH).
  • the acid-modifying group may be introduced by any compound. Examples of carboxylic anhydrides include unsaturated carboxylic anhydrides such as maleic anhydride and itaconic anhydride.
  • unsaturated polycarboxylic acids such as acid, itaconic acid and fumaric acid; saturated polycarboxylic acids such as succinic acid, glutaric acid and adipic acid; unsaturated monocarboxylic acids such as acrylic acid and methacrylic acid; , unsaturated carboxylic acid anhydride.
  • Unsaturated carboxylic acids or unsaturated carboxylic acid anhydrides can be used as radically polymerizable monomers to modify thermoplastic resins.
  • a polyvalent carboxylic acid can modify a thermoplastic resin by using it as a polycondensation monomer.
  • thermoplastic resin includes modified thermoplastic resins such as acid-modified thermoplastic resins.
  • the thermoplastic resin used in the present invention preferably contains at least one of polyamide resin, polyolefin resin, and acid-modified polyolefin resin. From the viewpoint of improving the strength of the thermoplastic resin molded article, it is preferably an acid-modified polyolefin resin.
  • the thermoplastic resin used in the present invention may optionally contain a crystal nucleating agent, a heat deterioration inhibitor, an oxidation deterioration inhibitor, an ultraviolet absorber, etc. for the purpose of improving physical properties, improving moldability, and improving durability. may contain additives. The content of these additives may vary depending on the purpose, but the total content of the additives is preferably 5% by mass or less, and 2% by mass or less, relative to 100% by mass of the thermoplastic resin. and more preferably 1% by mass or less.
  • the thermoplastic resin used in the present invention preferably has a melt flow rate of 15 to 100 g/10 minutes, more preferably 30 to 80 g/10 minutes when measured at a temperature of 230° C. and a load of 2.16 kg. Preferably, it is 40 to 60 g/10 minutes, more preferably. If the melt flow rate is lower than 15 g/10 minutes when measured at a temperature of 230°C and a load of 2.16 kg, impregnation of the inorganic fibers with the thermoplastic resin becomes insufficient, and there is a risk that impact absorption will decrease. be. On the other hand, if the melt flow rate exceeds 100 g/10 minutes when measured at a temperature of 230 ° C.
  • the melt flow rate of the resin is sometimes referred to as "MFR", and the MFR is measured in accordance with ISO 1133-1. value.
  • MFR melt flow rate of the resin
  • the preferred range of MFR of the resin contained in the thermoplastic resin tape used in the present invention is the same as the preferred range of MFR of the thermoplastic resin used in the present invention.
  • the inorganic fiber used in the present invention may be any inorganic fiber that is solid at the processing temperature of the thermoplastic resin used, and preferably contains at least one of glass fiber and carbon fiber, and may contain glass fiber. preferable.
  • the inorganic fibers are preferably sufficiently opened inorganic fibers. By sufficiently opening the inorganic fibers, the impregnation of the thermoplastic resin into the inorganic fibers can be enhanced, and as a result, the impact absorption can be enhanced. can be done.
  • the inorganic fibers are preferably short fibers.
  • the average fiber length of the inorganic fibers is preferably 5 to 200 mm, more preferably 10 to 150 mm, and more preferably 20 to 100 mm. More preferably, it is particularly preferably 30 to 50 mm.
  • the average fiber diameter of the inorganic fibers is preferably 3-30 ⁇ m, more preferably 5-20 ⁇ m. If the average fiber diameter is less than 3 ⁇ m, there is a risk that the impact absorption will decrease. If the average fiber diameter exceeds 30 ⁇ m, the number of inorganic fibers in the impact absorbing member is reduced, which may reduce impact absorption.
  • the average fiber length and average fiber diameter of inorganic fibers can be obtained by arithmetically averaging values measured based on JIS R 3420 using a scanning electron microscope (SEM).
  • the glass fiber is not particularly limited, and includes known glass fibers such as E glass, S glass, and C glass, preferably E glass. Only one type of glass fiber may be used, or two or more types may be used.
  • Carbon fibers are not particularly limited, and include polyacrylonitrile (PAN)-based carbon fibers, pitch-based carbon fibers, rayon-based carbon fibers, cellulose-based carbon fibers, vapor growth-based carbon fibers, graphitized fibers thereof, and the like. .
  • the carbon fibers preferably contain PAN-based carbon fibers.
  • PAN-based carbon fibers are carbon fibers made from polyacrylonitrile fibers.
  • Pitch-based carbon fibers are carbon fibers made from petroleum tar or petroleum pitch.
  • Cellulose-based carbon fibers are carbon fibers made from viscose rayon, cellulose acetate, or the like.
  • Vapor-grown carbon fibers are carbon fibers made from hydrocarbons or the like. Only one type of carbon fiber may be used, or two or more types may be used.
  • the inorganic fiber content in a given plate member is 30 to 60% by volume, preferably 35 to 55% by volume, more preferably 40 to 50% by volume. If the content is less than 30% by volume, the effect of reinforcing the plate-shaped member by the inorganic fiber cannot be obtained, and the stability of the impact-absorbing member against collision is lowered, so the breaking behavior of the impact-absorbing member becomes unstable, and the impact absorbency is reduced. On the other hand, if it exceeds 60% by volume, the production efficiency will be poor, and the impregnation of the inorganic fiber with the thermoplastic resin will be insufficient, resulting in unstable fracture behavior of the shock absorbing member and reduced shock absorption. put away.
  • the impact absorbing member of the present invention has a tubular portion formed of a predetermined plate-like member. By aligning the direction in which the impact acts with the axial direction of the cylindrical portion, it is possible to efficiently absorb the impact, and the thermoplastic resin layer containing inorganic fibers is close to a state in which multiple layers are laminated. When collision energy is applied to , the fracture progresses while causing delamination, so it is possible to further improve collision safety.
  • the bottom portion is preferably a plate-like member, more preferably a predetermined plate-like member, and the cylindrical portion and the bottom portion are composed of predetermined plate-like members. More preferably.
  • FIG. 1 is a perspective view of a shock absorbing member according to an embodiment of the invention.
  • the rectangular parallelepiped shock absorbing member 11 has four rectangular parallelepiped cylindrical portions 13 extending vertically from the outer circumference of one surface of a bottom surface portion 12 of a plate-like member having a rectangular shape when viewed in the thickness direction. are provided, and four rectangular parallelepiped internal spaces 14 are formed inside the impact absorbing member 11 in a grid pattern by being partitioned by the bottom surface portion 12 and the cylindrical portion 13 .
  • the outer shape of the impact absorbing member 11 is a shape in which plate-like members are erected in the vertical direction of the bottom surface portion 12 from the four sides which are the outer periphery of the bottom surface portion 12 .
  • the inner space 14 is formed by the bottom surface portion 12 and the cylindrical portion 13, and the plate-like member of the cylindrical portion 13 positioned inside the impact absorbing member 11 is common to the formation of the two inner spaces 14. used.
  • the bottom surfaces of the four internal spaces 14 in the axial direction are all closed by the bottom surface portion 12, and the side surfaces of the four internal spaces 14 are all constituted by the cylindrical portions 13, but the four internal spaces None of the top surfaces of 14 are blocked.
  • the bottom part 12 is not particularly limited, and may be a plate-like, mesh-like, lattice-like member, or the like. Among them, a plate-like member is preferable, but the bottom surface portion 12 does not need to be completely planar as long as it covers one bottom surface of the cylindrical portion 13, and may have partial unevenness. .
  • the thickness of the bottom portion is not particularly limited, and is preferably 1 to 8 mm, more preferably 2 to 6 mm.
  • the thickness of the bottom portion 12 refers to the thickness of the thinnest portion of the bottom portion 12, and the thickness of the thickest portion of the bottom portion 12 is preferably twice or less than the thickness of the bottom portion.
  • the shape of the bottom portion 12 viewed from the thickness direction is not particularly limited, and examples thereof include circular, elliptical, and polygonal shapes, but some of these shapes are possible. or a combination of these shapes. From the viewpoint of increasing the geometrical moment of inertia of the energy absorbing region to efficiently absorb energy, the shape of the bottom portion 12 viewed from the thickness direction is circular, and the ratio of the length of the minor axis to the major axis is 0.5.
  • the bottom portion 12 may be formed with through holes for ventilation, bolt fastening, wiring, and the like.
  • the holes may be formed by using a shear or the like in the mold at the same time as the impact absorbing member is molded, or may be formed by drilling, punching, cutting, or the like as post-processing.
  • the cylindrical portion 13 is provided so as to extend from the bottom surface portion 12 in a direction perpendicular to the bottom surface of the bottom surface portion 12 (thickness direction of the bottom surface portion), and the cylindrical portion 13 is preferably a plate-like member. If the tubular portion 13 is a plate-like member, collision energy is applied along the axial direction of the plate-like member, and the plate-like member deforms when the magnitude of the collision energy exceeds the limit value of the plate-like member. The impact energy is efficiently absorbed. Moreover, from the viewpoint of efficiently absorbing collision energy, it is preferable that all the heights of the cylindrical portions 13 are the same.
  • the cylindrical portion 13 preferably has a shape in which a plate-like member is erected in a direction perpendicular to the bottom portion 12 from at least a part of the outer periphery of the bottom portion 12. It is more preferable to have a cylindrical member erected vertically from the entire outer circumference of the bottom surface portion 12, but in order to adjust the amount of collision energy absorption, A plate-like member may be erected vertically from the inner side of the bottom surface portion 12 .
  • the height of the tubular portion 13 is not particularly limited, but when the bottom portion 12 has a circular, elliptical, equilateral triangle, square, rectangular, regular hexagonal, or hexagonal shape when viewed from the thickness direction, the bottom portion 12 It is preferably 0.5 to 3 times, more preferably 0.6 to 2 times, and even more preferably 0.65 to 1.5 times the shortest side or minor axis of . If the height of the cylindrical portion 13 is less than 0.5 times the shortest side or minor axis of the bottom portion 12, collision energy will be applied to the cylindrical portion 13 to cause destruction or deformation. The space for deformation is insufficient, and the breaking behavior of the impact absorbing member 11 becomes unstable, which may lead to a decrease in impact absorption.
  • the molding cost may increase.
  • the cylindrical part 13 is preferably provided in a direction perpendicular to the bottom surface of the bottom part 12, but it does not have to be strictly perpendicular as long as the shock absorption can be ensured.
  • the angle between the bottom portion 12 and the tubular portion 13 is preferably 30 to 120°, more preferably 40 to 90°.
  • the cylindrical portion 13 may be provided with an angle for securing the draft angle of the mold to the extent that the intention of the present invention is not impaired.
  • the thickness of the cylindrical portion 13 is not particularly limited, and may be the same as or different from the thickness of the bottom portion 12, preferably 1 to 8 mm, more preferably 2 to 6 mm.
  • the tubular portion 13 forms two or more closed cross-sectional structures when viewed from the axial direction of the tubular portion 13 (thickness direction of the bottom surface portion 12).
  • the closed cross-sectional structure is not particularly limited, but from the viewpoint of efficiently absorbing collision energy, it preferably has a line-symmetrical or point-symmetrical shape, such as a circular shape, an elliptical shape, a polygonal shape, or any of these shapes. However, a triangular, rectangular, square, or hexagonal shape is preferable because the internal spaces 14 can be arranged without gaps.
  • the difference between the inorganic fiber content in the cylindrical portion and the inorganic fiber content in the bottom portion is preferably 5% by volume or less, more preferably 3% by volume or less, and 2% by volume or less. is more preferable, and 1.5% by volume or less is particularly preferable. If the content exceeds 5% by volume, the impact energy (stress) concentration point may occur at an unexpected location, resulting in a decrease in impact absorption. In addition, when a commercially available stampable sheet such as GMT (Glass Mat reinforced Thermoplastics) is used, the content exceeds 5% by volume, and the tip of the cylindrical portion is resin-rich with a lower inorganic fiber content than the other portions.
  • GMT Glass Mat reinforced Thermoplastics
  • the shock absorbing member shatters into small pieces as the fracture progresses, or the elongation of the shock absorbing member increases, resulting in the same fracture behavior as when using a metal shock absorbing member. A bending-like deformation occurs, and the shock absorbing member breaks.
  • the "difference between the inorganic fiber content rate in the cylindrical portion and the inorganic fiber content rate in the bottom portion" refers to the axial direction of the outermost cylindrical portion.
  • the inorganic fiber content at the tip and the inorganic fiber content at the tip in the axial direction of the cylindrical portion other than the outermost periphery is large value.
  • the content of inorganic fibers is measured at the part farthest from the part joined to the cylindrical part (for example, the hatched part (measurement part 41) in FIG. 4 for the shock absorbing member in FIG. 1). .
  • FIG. 2 is a perspective view of a modification of the shock absorbing member according to the embodiment of the invention.
  • the impact absorbing member 21 having a rectangular parallelepiped shape is a plate-like member having a rectangular shape when viewed from the thickness direction. is provided in Four hexagonal prism-shaped internal spaces 24 are provided inside the shock absorbing member 21 so as to form a honeycomb structure by being partitioned by the bottom surface portion 22 and the tubular portion 23 , but are arranged in the axial direction of the shock absorbing member 21 . In the vicinity of the outer periphery of the , there is also a part, such as the internal space 25, which is shaped like a part of a hexagonal column.
  • the outer shape of the impact absorbing member 21 is a shape in which plate-like members are erected in the vertical direction of the bottom surface portion 22 from the four sides which are the outer periphery of the bottom surface portion 22 .
  • the cylindrical portion 23 defines the internal spaces 24 and 25, and the plate-like member of the cylindrical portion 23 located inside the impact absorbing member 21 forms two internal spaces 24, the internal space 24 and the internal space. It is commonly used to form the space 25 or to form two internal spaces 25 .
  • the axial bottom surfaces of the internal spaces 24 and 25 are closed by the bottom surface portion 22, and the side surfaces are both formed by the tubular portion 23, but the upper surfaces are not closed.
  • FIG. 3 is a perspective view of a further modified example of the impact absorbing member according to the embodiment of the present invention.
  • the impact absorbing member 31 has four cylindrical tubular members extending vertically from one surface of the bottom surface portion 32 at the central portion of the bottom surface portion 32 of a plate-like member having a rectangular shape when viewed in the thickness direction.
  • a portion 33 is provided.
  • the bottom portion 32 and the tubular portion 33 are formed so that a gap (internal space 35 to be described later) created between the tubular portions 33 is minimized, and is surrounded by three adjacent internal spaces 34 .
  • An internal space 35 is formed.
  • the axial bottom surfaces of the internal spaces 34 and 35 are closed by the bottom surface portion 32, and the side surfaces are both formed by the tubular portion 33, but the upper surfaces are not closed.
  • ⁇ Method for manufacturing shock absorbing member> In the method for manufacturing a shock absorbing member of the present invention, the direction of orientation of inorganic fibers in a predetermined plate-like member included in the shock absorbing member satisfies the above-described predetermined requirements, and the content of inorganic fibers in the predetermined plate-like member is is within the range.
  • a thermoplastic resin tape is obtained by cutting, then a relatively thick thermoplastic resin sheet is produced using the cut thermoplastic resin tape, and finally the thick thermoplastic resin sheet is put into a mold for molding. It is preferable to obtain an impact absorbing member having a desired shape by doing so.
  • thermoplastic resin tape the relatively thin thermoplastic resin sheet
  • thin thermoplastic resin sheet A relatively thick thermoplastic resin sheet is sometimes referred to as a “thick thermoplastic resin sheet”.
  • thermoplastic resin sheet can be produced by impregnating an open inorganic fiber roving with a resin, crushing it with a shaping roller, and solidifying it by cooling. Then, the thin thermoplastic resin sheet is cut by a cutter such as a fan cutter to produce a thin thermoplastic resin sheet.
  • the inorganic fibers In the fiber opening process, it is preferable to use the inorganic fibers after aligning and sufficiently opening them. It is desirable to do so in a state in which there is little twisting, and roller and air opening processes are usually used, but are not limited to these.
  • a pressure of 0.1 MPa In order to continuously and efficiently impregnate the thermoplastic resin, it is preferable to apply a pressure of 0.1 MPa to the resin (pass it through a resin impregnation bath having a pressure of 0.1 MPa or more). When it is less than 0.1 MPa, it becomes difficult to obtain sufficient impregnation.
  • thermoplastic resin impregnation tank tend to be bundled together due to the pulling tension, and in this state, the details of the inorganic fibers are not completely impregnated with the thermoplastic resin. Therefore, resin impregnability and handleability can be improved by crushing with a shaping roller and solidifying by cooling to produce a thermoplastic resin tape.
  • the thick thermoplastic resin sheet is made by randomly scattering the thermoplastic resin tapes obtained as described above, laminating them, and using a compression molding machine in which a mold whose temperature has been adjusted to the melting point or higher of the thermoplastic resin is set. It can be obtained by compressing, cooling the mold, and opening the mold.
  • the inorganic fibers are oriented in a direction perpendicular to the thickness direction of the thick thermoplastic resin sheet, and , the inorganic fibers are oriented in the planar direction of the thick thermoplastic resin sheet, and the orientation in the direction orthogonal to the planar direction is random.
  • press molding described later is performed using such a thick thermoplastic resin sheet
  • the inorganic fibers are oriented in a direction perpendicular to the thickness direction of the plate-like member, and in-plane along the perpendicular direction. It is possible to mold a plate-like member in which the inorganic fibers are randomly oriented.
  • a shock absorbing member having such a plate-like member is used, delamination occurs when collision energy is applied, and destruction progresses, so that collision safety can be improved.
  • the mold temperature is preferably below the solidification temperature of the thermoplastic resin, preferably from -60°C to -10°C. The higher the mold temperature, the higher the moldability of the thick thermoplastic resin sheet, but the lower the mold temperature, the better in order to prevent warping of the thick thermoplastic resin sheet.
  • the press pressure is preferably 0.1 MPa or more, more preferably 1 MPa or more. If the pressure is less than 0.1 MPa, sufficient pressure is not applied to the thermoplastic resin tape, and air bubbles may be generated or the surface quality may be deteriorated.
  • a higher press pressure is preferable because the quality of the sheet is higher.
  • the press holding time is preferably 0.5 to 20 minutes, more preferably 1 to 10 minutes.
  • Press molding is preferable as a molding method for producing the impact absorbing member of the present invention using a thermoplastic resin sheet.
  • press molding include a heat & cool molding method and a stamping molding method, but the stamping molding method is preferred in terms of cycle time and molding cost.
  • stamping molding the thermoplastic resin sheet is heated and melted to a temperature above the melting point of the thermoplastic resin using infrared heating or high-frequency heating, supplied to a mold adjusted to a temperature below the melting point, and removed from the mold after cooling. refers to the molding performed by Molding conditions such as mold temperature, press pressure, and press holding time during stamping molding may be appropriately set according to the thermoplastic resin to be used, but the following conditions are preferred.
  • the mold temperature is preferably below the solidification temperature of the thermoplastic resin, preferably from -60°C to -10°C. The higher the mold temperature, the higher the moldability, but the lower the mold temperature, the better, in order to prevent warping of the molded body.
  • the press pressure is preferably 1 MPa or more, more preferably 10 MPa or more.
  • the press holding time is preferably 1 to 10 minutes, more preferably 1 to 5 minutes.
  • the thermoplastic resin tape is obtained by cutting the thermoplastic resin sheet, so it is preferable that the thin thermoplastic resin sheet also have the same thickness as the thermoplastic resin tape.
  • the thickness of the thick thermoplastic resin sheet is preferably 0.35 to 1.2 mm, more preferably 0.5 to 1.0 mm. If the thickness is less than 0.35 mm, production efficiency may deteriorate, and if it exceeds 1.2 mm, it is not preferable from the viewpoint of cost.
  • the content rate of inorganic fibers in the vicinity of the center of the bottom part in the internal space is measured, and the vicinity of the center of the bottom part in the internal space is the diagonal line in FIG. It is a part (measurement part 41), and the same applies to FIGS. 2 and 3 as well.
  • the tip in the axial direction of the cylindrical portion is the tip on the side to which collision energy is first applied (the tip on the side opposite to the bottom portion).
  • the outermost cylindrical portion means a cylindrical portion other than the portion commonly used to form two internal spaces (the portion used to form only one internal space). Point.
  • ⁇ Falling weight impact test> Using a large high-speed impact compression tester (IM10T-30, manufactured by IMATEK), a falling weight impact test was performed on the produced impact-absorbing member.
  • the falling weight impact test was performed by free-falling a cone weighing 121.2 kg from a position 2.5 m higher than the impact absorbing member, thereby applying an impact compressive load in the axial direction of the impact absorbing member.
  • the impact load was measured from a load cell attached to the cone side. From the measured impact load and displacement, a load-displacement curve was drawn and integrated to calculate the absorbed energy of the impact-absorbing member during the falling weight impact test. The specific absorbed energy was calculated by dividing the calculated absorbed energy by the weight of the portion destroyed by the falling weight impact test.
  • ⁇ Average Orientation Angle> In the shock absorbing member of FIG. 1, the average orientation angle of the inorganic fibers with respect to the plane perpendicular to the thickness direction in the bottom portion was measured. Specifically, the orientation angle of each inorganic fiber was measured near the center of the bottom portion of the internal space 14 (hatched portion (measurement portion 41) in FIG. 4), and the average orientation angle was calculated.
  • Example 1 A glass fiber roving (manufactured by Nittobo Co., Ltd., RS 110 QL-483, E glass, fineness: 1150 Tex, number of bundles f: 2000, average fiber diameter: 17 ⁇ m), which is an inorganic fiber, was opened using a roller with a diameter of 2 cm. . Next, Prime Polymer J137M (temperature 230 ° C., MFR at 2.16 kg load: 30 g / 10 minutes) and Asahi Techno Kogyo Co., Ltd.
  • thermoplastic resin sheet was cut to produce a thermoplastic resin tape A having a width of 30 mm, a length of 35 mm, and a thickness of 0.1 mm with an inorganic fiber content of 48% by volume.
  • thermoplastic resin tape A was randomly laminated in a metal heat-resistant release container, and then pressed for 5 minutes with a pressure of 0.2 MPa in a mold heated to 240 ° C., and the inside of the sheet After the air was sufficiently removed, a stamping molding sheet having a thickness of 6 mm was produced by pressing for 2 minutes at a pressure of 2 MPa in a mold set at 100°C.
  • the prepared sheet for stamping molding is cut out to have the same volume as the mold volume, heated with a far infrared heater until the sheet for stamping molding reaches 220 ° C., then put into the mold set at 130 ° C. and pressurized.
  • a shock absorbing member having the shape shown in FIG.
  • the shock absorbing member of FIG. 1 was obtained by performing stamping molding at 25 MPa for a dwell time of 2 minutes.
  • the shock absorbing member of FIG. 1 had a bottom portion of 80 mm long, 100 mm wide and 4 mm thick, a tubular portion 52 mm high, and a thickness of 2.2 mm at the tip of the tubular portion.
  • the height of the tubular portion was 0.65 times the shortest side of the bottom portion.
  • the content of inorganic fibers in the bottom portion of the shock absorbing member of Example 1 was 47.5% by volume, and the content of inorganic fibers in the tubular portion located on the outermost periphery was 47.9% by volume.
  • the content of inorganic fibers in the cylindrical portion other than the above was 48.4% by volume.
  • the specific absorbed energy of the impact absorbing member in Example 1 was 36.6 kJ/kg, and the average orientation angle was 3.7°.
  • Example 2 A sheet for stamping molding was produced in the same manner as in Example 1. The prepared sheet for stamping molding was cut out, heated with a far-infrared heater until the sheet for stamping molding reached 220°C, and then put into a mold set at 130°C for stamping molding. A shaped impact absorbing member was obtained.
  • the impact-absorbing member of FIG. 2 had a bottom portion of 60 mm long, 60 mm wide and 4 mm thick, a tubular portion 52 mm high, and a thickness of 2.2 mm at the tip of the tubular portion. The height of the tubular portion was 0.87 times the shortest side of the bottom portion.
  • the content of inorganic fibers in the bottom portion of the shock absorbing member of Example 2 was 47.8% by volume, and the content of inorganic fibers in the tubular portion located on the outermost periphery was 48.2% by volume.
  • the content of inorganic fibers in the cylindrical portion other than the above was 47.5% by volume.
  • the specific absorbed energy of the shock absorbing member in Example 2 was 40.5 kJ/kg.
  • Example 3 Instead of the glass fiber roving described in Example 1, carbon fiber roving (T-700 manufactured by Toray Industries, polyacrylonitrile, fineness: 800 Tex, 12000 f, average fiber diameter: 7 ⁇ m) was used in Example 1.
  • maleic acid-modified polypropylene G2H manufactured by Toyobo Co., Ltd., temperature 230 ° C., MFR at a load of 2.16 kg: 50 g / 10 minutes
  • a thermoplastic resin tape B having a width of 15 mm, a length of 35 mm, and a thickness of 0.1 mm and having an inorganic fiber content of 50% was produced.
  • a shock absorbing member having the shape shown in FIG. 1 was obtained in the same manner as in Example 1 except that the thermoplastic resin tape B was used instead of the thermoplastic resin tape A.
  • the content of inorganic fibers in the bottom portion of the shock absorbing member of Example 3 was 49.4% by volume, and the content of inorganic fibers in the tubular portion located on the outermost periphery was 50.3% by volume.
  • the content of the inorganic fibers in the tubular portion other than the above was 50.1% by volume.
  • the specific absorbed energy of the impact absorbing member in Example 3 was 49.5 kJ/kg.
  • Example 4 A shock absorbing member having the shape shown in FIG.
  • the content of inorganic fibers in the bottom portion of the shock absorbing member of Example 4 was 50.3% by volume, and the content of inorganic fibers in the cylindrical portion located on the outermost periphery was 49.8% by volume.
  • the content of inorganic fibers in the cylindrical portion other than the above was 49.9% by volume.
  • the specific absorbed energy of the shock absorbing member in Example 4 was 54.2 kJ/kg.
  • Example 1 Except for using Mitsubishi Chemical Advanced Materials P4038 GMT (GMT, fiber length: 100 mm, inorganic fiber content: 20% by volume, thickness: 3.8 mm) containing polypropylene and glass fiber to prepare a sheet for stamping molding.
  • a shock absorbing member having the shape shown in FIG. 1 was obtained in the same manner as in Example 1.
  • the content of inorganic fibers in the bottom portion of the shock absorbing member of Comparative Example 1 was 24.8% by volume, and the content of inorganic fibers in the cylindrical portion located on the outermost periphery was 17.8% by volume.
  • the content of inorganic fibers in the cylindrical portion other than the above was 16.2% by volume.
  • the specific absorbed energy of the shock absorbing member in Comparative Example 1 was 21.5 kJ/kg.
  • the behavior at the time of destruction in the falling weight impact test progressed while breaking into pieces from the vicinity of the contact point with the cone.
  • (Comparative example 2) A shock absorbing member having the shape shown in FIG.
  • the inorganic fiber content in the bottom portion of the shock absorbing member of Comparative Example 2 was 24.2% by volume, and the inorganic fiber content in the outermost cylindrical portion was 16.8% by volume.
  • the content of inorganic fibers in the cylindrical portion other than the above was 18.5% by volume.
  • the specific absorbed energy of the shock absorbing member in Comparative Example 2 was 25.2 kJ/kg.
  • the behavior at the time of destruction in the falling weight impact test as in Comparative Example 1, the destruction progressed while breaking into pieces from the vicinity of the contact point with the cone.
  • the shock absorbing member of the present invention can achieve both weight reduction and high collision safety, and is excellent in moldability, so that it can be used as a shock absorbing device for passenger cars, and can be used to reduce the weight of the vehicle body and save energy. It is expected that it will contribute greatly to the industrial world.
  • the impact absorbing member of the present invention can be used not only for impact absorbing devices for passenger cars, but also for vehicles other than passenger cars and various structures.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Composite Materials (AREA)
  • Vibration Dampers (AREA)

Abstract

Provided is an impact-absorbing member of which the shape can be designed relatively freely, which is lightweight, and which has high collision safety. This impact-absorbing member has one or more plate-shaped members, and is characterized in that: at least one of the plate-shaped members is formed by laminating a thermoplastic resin tape containing inorganic fibers; in the plate-shaped member containing the inorganic fibers, the inorganic fibers are oriented in a direction perpendicular to the thickness direction of the plate-shaped member, and have random orientations in a plane along the perpendicular direction; and the inorganic fibers account for 30-60 vol% in the plate-shaped member.

Description

衝撃吸収部材shock absorbing material
　本発明は、衝撃吸収部材に関する。 The present invention relates to shock absorbing members.
　従来、乗用車等の車両の乗員保護のために、衝突エネルギーを吸収する衝撃吸収部材が配置されている。例えば、車両には衝撃が入力されると予想される箇所にフロントサイドメンバやリアサイドメンバなどの衝撃吸収部材が配置されている。衝撃吸収部材においては、効率良く衝突エネルギーを吸収できる方向である軸方向に衝突エネルギーが加わり、衝突エネルギーの大きさが降伏応力を超えると、衝撃吸収部材が変形して衝撃を吸収する。 　Conventionally, in order to protect the occupants of vehicles such as passenger cars, shock absorbing members that absorb collision energy have been arranged. For example, impact absorbing members such as front side members and rear side members are arranged in locations where impacts are expected to be applied to the vehicle. In the shock absorbing member, collision energy is applied in the axial direction, which is the direction in which collision energy can be efficiently absorbed, and when the magnitude of the collision energy exceeds the yield stress, the shock absorbing member deforms and absorbs the shock.
　衝撃吸収部材においては、衝突エネルギーを十分かつ効率良く吸収することが重要であり、衝撃吸収部材は鋼板等の金属を用いて製造されることが多い。 　It is important for shock absorbing members to absorb impact energy sufficiently and efficiently, and shock absorbing members are often manufactured using metal such as steel plate.
　例えば、特許文献１には、筒状部材である自動車用衝突エネルギー吸収部品が開示されており、筒状部材には鋼板等の金属板が用いられている。筒状部材は天板部と縦壁部とフランジ部を有する断面ハット形状の部材と平板状の部材とが前記フランジ部においてスポット溶接されたものであり、筒状部材の軸方向先端に衝突体を衝突させた場合に効率良く衝突エネルギーが吸収されることが開示されている。 For example, Patent Document 1 discloses an automotive collision energy absorbing component that is a cylindrical member, and a metal plate such as a steel plate is used for the cylindrical member. The cylindrical member is formed by spot-welding a hat-shaped member having a top plate portion, a vertical wall portion, a flange portion, and a flat plate-shaped member at the flange portion. It is disclosed that the collision energy is efficiently absorbed when the .
　特許文献１の吸収部材では、衝突エネルギーは吸収できるものの、鋼板等の金属板を用いているため軽量であるとは言い難い。近年、高い衝突安全性が求められる一方で、燃費改善のために衝撃吸収部材の軽量化が求められているが、特許文献１のように鋼板等の金属板が用いられていると、軽量化を図るには限界があった。 Although the absorbing member of Patent Document 1 can absorb collision energy, it is difficult to say that it is lightweight because it uses metal plates such as steel plates. In recent years, while high collision safety is required, there is also a demand for weight reduction of shock absorbing members to improve fuel efficiency. There was a limit to trying to
　このような金属製の衝撃吸収部材の問題点に鑑み、軽量化効果の高い樹脂製の衝撃吸収部材が提案されている。しかし、金属製の衝撃吸収部材を単に樹脂製の衝撃吸収部材に置き換えただけでは、衝撃吸収性が低下してしまう。一方、衝撃吸収性の低下を避けるために、衝撃吸収部材を厚くすると、衝撃吸収部材の重量が増加してしまい燃費改善が図れない。樹脂を用いて軽量化を図りながら高い衝突安全性も有する衝撃吸収部材として、例えば特許文献２～４のような衝撃吸収部材が開示されている。 In view of such problems of metal shock absorbing members, resin shock absorbing members that are highly effective in reducing weight have been proposed. However, simply replacing the metal shock absorbing member with a resin shock absorbing member will reduce the shock absorbing performance. On the other hand, if the impact absorbing member is made thicker to avoid a decrease in impact absorbing performance, the weight of the impact absorbing member increases, making it impossible to improve fuel efficiency. For example, patent documents 2 to 4 disclose impact-absorbing members as impact-absorbing members that use resin to reduce weight and have high collision safety.
　特許文献２には、補強繊維と樹脂とからなる筒状断面の繊維強化プラスチック製エネルギー吸収部と、前記繊維強化プラスチック製エネルギー吸収部に連なり繊維強化プラスチックで形成されて車体部品と接合される支持部と、からなるフロントサイドメンバが開示されており、熱硬化性樹脂を含浸させた連続繊維シートをシートワインディングする方法又は強化繊維の織布を予備賦形しＲＴＭ工法を行うことでエネルギー吸収部材を作製する方法が記載されている。 Patent Document 2 discloses a fiber-reinforced plastic energy absorbing portion having a cylindrical cross section made of reinforcing fibers and resin, and a support connected to the fiber-reinforced plastic energy absorbing portion and formed of fiber-reinforced plastic and joined to a vehicle body part. A front side member consisting of a part is disclosed, and an energy absorbing member is formed by a method of sheet winding a continuous fiber sheet impregnated with a thermosetting resin or by preforming a woven fabric of reinforcing fibers and performing an RTM method is described.
　特許文献３には、エネルギー吸収部材として、強化繊維糸と、該強化繊維糸に含浸された樹脂組成物とで構成される繊維強化樹脂中空円筒体が開示されており、該中空円筒体はフィラメントワインディング法によって成形されることが開示されている。 Patent Document 3 discloses, as an energy absorbing member, a fiber-reinforced resin hollow cylindrical body composed of reinforcing fiber threads and a resin composition impregnated in the reinforcing fiber threads, and the hollow cylindrical body is composed of filaments. It is disclosed to be formed by a winding method.
　特許文献４には、筒状部と、その軸方向の一方の開口部を塞ぐように形成された天面部とを有する車両用衝撃吸収部材が開示されており、特許文献４の衝撃吸収部材では、天面部に入力される衝撃荷重にて前記軸方向に圧縮変形することによって、衝撃エネルギーを吸収することが開示されている。 Patent Document 4 discloses a vehicle shock absorbing member having a cylindrical portion and a top surface portion formed to block one opening in the axial direction. , the impact energy is absorbed by compression deformation in the axial direction due to the impact load input to the top surface.
特開２０１９－２０６２４６号公報JP 2019-206246 A 特開２００５－２７１８７５号公報JP 2005-271875 A 国際公開第２０２０／２１７５７３号WO2020/217573 特開２０２１－６７２９１号公報Japanese Patent Application Laid-Open No. 2021-67291
　しかし、特許文献２や特許文献３の吸収部材中には強化繊維（補強繊維）が連続繊維として存在するため、成形コストが高くなる上に、成形性が乏しく成形できる形状が限定されてしまい、後述する図１や図２のように衝撃吸収部材を複雑な形状とすることは困難であった。 However, since reinforcing fibers (reinforcing fibers) are present as continuous fibers in the absorbent members of Patent Documents 2 and 3, the molding cost is high and the shape that can be molded is limited due to poor moldability. It was difficult to make the impact absorbing member into a complicated shape as shown in FIGS. 1 and 2, which will be described later.
　特許文献４の衝撃吸収部材は、筒状部の内側に少なくとも１つ以上の衝撃時の荷重を支えるためのリブが、天面部と接続され、かつ前記筒状部とは離間して設けられた特殊な形状であり、衝撃吸収部材の形状が限定されてしまうという問題があった。また、特許文献４の衝撃吸収部材は、射出成形での成形を想定しているため、材料が破壊する際の衝撃吸収部材のエネルギー吸収量を高めることが困難であり、衝撃吸収性が低くなってしまうという問題があった。 In the shock absorbing member of Patent Document 4, at least one rib for supporting the load at the time of impact is provided inside the cylindrical portion, connected to the top surface portion and spaced apart from the cylindrical portion. Since it has a special shape, there is a problem that the shape of the shock absorbing member is limited. In addition, since the shock absorbing member of Patent Document 4 is assumed to be formed by injection molding, it is difficult to increase the energy absorption amount of the shock absorbing member when the material breaks, and the shock absorbing property becomes low. I had a problem with it.
　本発明の目的は、形状を比較的自由に設定できる上に、軽量であり、かつ高い衝突安全性を有する衝撃吸収部材を提供することにある。 An object of the present invention is to provide an impact absorbing member whose shape can be set relatively freely, which is lightweight, and which has high collision safety.
　本発明者は上記課題を解決するため鋭意検討した結果、無機繊維を含む熱可塑性樹脂テープが積層されて形成された板状部材を有する衝撃吸収部材とし、該板状部材における無機繊維の配向を所定の条件を満たすように制御することによって、軽量化を図りつつ、高い衝突安全性を有する衝撃吸収部材を見出し、本発明に到達した。 As a result of intensive studies in order to solve the above problems, the inventors of the present invention provided a shock absorbing member having a plate-like member formed by laminating thermoplastic resin tapes containing inorganic fibers, and the orientation of the inorganic fibers in the plate-like member. The inventors have found a shock absorbing member that achieves weight reduction and high collision safety by controlling the weight so as to satisfy predetermined conditions, and arrived at the present invention.
　すなわち、本発明は、以下の構成からなる。
　［１］１つ以上の板状部材を有する衝撃吸収部材であって、前記板状部材の少なくとも１つが、無機繊維を含む熱可塑性樹脂テープが積層されて形成されたものであり、該無機繊維を含む板状部材において、前記無機繊維が板状部材の厚み方向に垂直な方向に配向していると共に、該垂直方向に沿った面内での配向がランダムであり、かつ前記無機繊維が前記板状部材中、３０～６０体積％であることを特徴とする衝撃吸収部材。
　［２］前記無機繊維が、ガラス繊維及び炭素繊維の少なくとも一種を含む前記［１］に記載の衝撃吸収部材。
　［３］前記無機繊維の平均繊維長が１０～１５０ｍｍである前記［１］又は［２］に記載の衝撃吸収部材。
　［４］温度２３０℃、荷重２．１６ｋｇで測定したときの前記熱可塑性樹脂テープ中に含まれる樹脂のメルトフローレートが１５～１００ｇ／１０分である前記［１］～［３］のいずれかに記載の衝撃吸収部材。
　［５］前記熱可塑性樹脂テープは、長さ１０ｍｍ～１００ｍｍ、幅５ｍｍ～５０ｍｍ、厚み０．０５ｍｍ～０．３ｍｍである前記［１］～［４］のいずれかに記載の衝撃吸収部材。
　［６］筒状部と底面部とを有する衝撃吸収部材であって、前記筒状部及び前記底面部は前記板状部材により構成されており、前記底面部は、前記筒状部の一方の底面を塞いでおり、前記筒状部における前記無機繊維の含有率と前記底面部における前記無機繊維の含有率との差が５体積％以下である前記［１］～［５］のいずれかに記載の衝撃吸収部材。
　［７］前記底面部において、厚み方向に垂直な面に対する前記無機繊維の平均配向角度が０～２０°である前記［１］～［６］のいずれかに記載の衝撃吸収部材。 That is, the present invention consists of the following configurations.
[1] A shock absorbing member having one or more plate-like members, wherein at least one of the plate-like members is formed by laminating thermoplastic resin tapes containing inorganic fibers, and the inorganic fibers In the plate-shaped member comprising the A shock absorbing member characterized by comprising 30 to 60% by volume of the plate member.
[2] The impact absorbing member according to [1] above, wherein the inorganic fibers include at least one of glass fibers and carbon fibers.
[3] The impact absorbing member according to [1] or [2], wherein the inorganic fibers have an average fiber length of 10 to 150 mm.
[4] Any one of the above [1] to [3], wherein the melt flow rate of the resin contained in the thermoplastic resin tape is 15 to 100 g/10 minutes when measured at a temperature of 230° C. and a load of 2.16 kg. The shock absorbing member according to .
[5] The impact absorbing member according to any one of [1] to [4], wherein the thermoplastic resin tape has a length of 10 mm to 100 mm, a width of 5 mm to 50 mm, and a thickness of 0.05 mm to 0.3 mm.
[6] A shock absorbing member having a tubular portion and a bottom portion, wherein the tubular portion and the bottom portion are composed of the plate-shaped member, and the bottom portion is formed on one side of the tubular portion. Any one of the above [1] to [5], wherein the bottom is closed, and the difference between the inorganic fiber content in the cylindrical portion and the inorganic fiber content in the bottom portion is 5% by volume or less. A shock absorbing member as described.
[7] The impact-absorbing member according to any one of [1] to [6], wherein the average orientation angle of the inorganic fibers with respect to the plane perpendicular to the thickness direction in the bottom portion is 0 to 20°.
　無機繊維を含む熱可塑性樹脂テープが積層されて形成された板状部材を有する衝撃吸収部材とし、該板状部材における無機繊維の配向を所定の条件を満たすように制御することによって、軽量化と高い衝突安全性とを両立させることができた。また、本発明の衝撃吸収部材は成形性に優れており、形状を比較的自由に設定できるため、乗用車の衝撃吸収装置に用いることができるのみならず、乗用車以外の車両や各種構造物にも用いることができる。 A shock absorbing member having a plate-shaped member formed by laminating thermoplastic resin tapes containing inorganic fibers, and controlling the orientation of the inorganic fibers in the plate-shaped member so as to satisfy a predetermined condition, thereby reducing the weight. We were able to achieve both high collision safety. In addition, the impact absorbing member of the present invention has excellent moldability and can be shaped relatively freely. Therefore, it can be used not only for impact absorbing devices for passenger cars, but also for vehicles other than passenger cars and various structures. can be used.
本発明の実施の形態に係る衝撃吸収部材の斜視図である。1 is a perspective view of a shock absorbing member according to an embodiment of the invention; FIG. 本発明の実施の形態に係る衝撃吸収部材の変形例の斜視図である。FIG. 4 is a perspective view of a modification of the shock absorbing member according to the embodiment of the invention; 本発明の実施の形態に係る衝撃吸収部材のさらなる変形例の斜視図である。FIG. 11 is a perspective view of a further modified example of the shock absorbing member according to the embodiment of the present invention; 図１の衝撃吸収部材の底面図である。FIG. 2 is a bottom view of the shock absorbing member of FIG. 1;
　以下、本発明を詳細に説明する。 The present invention will be described in detail below.
　本発明の衝撃吸収部材は、１つ以上の板状部材を有する。なお、本明細書では、「板状部材」は、平面状の部材のみならず、波板状、円柱状、半円柱状、半球状のような曲板状、ジグザグ状のような折り畳んだ形状などの部材なども包含し、これらの形状の一部やこれらの形状の組み合わせであってもよい。 The shock absorbing member of the present invention has one or more plate-shaped members. In this specification, the term “plate-shaped member” refers not only to planar members, but also to bent shapes such as corrugated plates, cylinders, semi-cylindrical shapes, hemispherical shapes, and folded shapes such as zigzag shapes. and the like, and may be a part of these shapes or a combination of these shapes.
＜板状部材＞
　本発明では、前記板状部材の少なくとも１つが、無機繊維を含む熱可塑性樹脂テープが積層されて形成されたものであり、該無機繊維を含む板状部材において、前記無機繊維が板状部材の厚み方向に垂直な方向に配向していると共に、該垂直方向に沿った面内での配向がランダムである。なお、以下では、「無機繊維を含む熱可塑性樹脂テープが積層されて形成されたものであり、該無機繊維を含む板状部材において、前記無機繊維が板状部材の厚み方向に垂直な方向に配向していると共に、該垂直方向に沿った面内での配向がランダム」である板状部材のことを「所定の板状部材」という。 <Plate member>
In the present invention, at least one of the plate-like members is formed by laminating thermoplastic resin tapes containing inorganic fibers, and in the plate-like member containing inorganic fibers, the inorganic fibers are the plate-like member. It is oriented in the direction perpendicular to the thickness direction, and the orientation in the plane along the perpendicular direction is random. In addition, hereinafter, “a plate-shaped member formed by laminating thermoplastic resin tapes containing inorganic fibers, in which the inorganic fibers extend in a direction perpendicular to the thickness direction of the plate-shaped member A plate-shaped member that is oriented and whose orientation in the plane along the vertical direction is random is referred to as a 'predetermined plate-shaped member'.
　所定の板状部材では、無機繊維が厚み方向に垂直な方向に配向しているため、優れた衝突安全性を発揮する。以下に、所定の板状部材を有する本発明の衝撃吸収部材が衝撃吸収性（衝突安全性）に優れる理由について説明するが、その前に、金属製の衝撃吸収部材を用いた場合の破壊状況、及び、熱可塑性樹脂を用いて衝撃吸収部材を従来の方法で成形した場合の問題点の説明を行う。 In a given plate-shaped member, the inorganic fibers are oriented in a direction perpendicular to the thickness direction, so it exhibits excellent collision safety. The reason why the shock absorbing member of the present invention having a predetermined plate-shaped member is excellent in shock absorbing property (collision safety) will be explained below. , and problems in the case where the impact absorbing member is molded by the conventional method using the thermoplastic resin.
　金属製の衝撃吸収部材の場合、全体的な折れが生じるような破壊形態となるため、衝撃吸収部材が衝突エネルギーを安定的に吸収できない。そのため金属製の衝撃吸収部材は、衝突エネルギーが加わったときに局部的に座屈しながら、全体的には蛇腹状に圧壊が進行するよう設計されている。 　In the case of a metal shock absorbing member, the shock absorbing member cannot stably absorb the collision energy because it will be broken in such a way that the entire body will break. Therefore, the metal shock absorbing member is designed so that when collision energy is applied, it locally buckles while the overall collapse progresses in a bellows-like manner.
　無機繊維を含む熱可塑性樹脂を用いて衝撃吸収部材を成形した場合に金属製の衝撃吸収部材と同様の破壊形態となるような設計を行うと、熱可塑性樹脂の伸度が小さいため、金属製の衝撃吸収部材のような延性的な破壊ではなく、脆性的な破壊が生じてしまう。脆性的な破壊が生じると、衝撃吸収部材にかかる衝撃荷重が衝撃吸収部材の破壊中に大きく変動するため、衝突エネルギーを安定的に吸収できないばかりか、破壊途中で衝撃吸収部材が衝撃荷重に耐えきれなくなるおそれがあった。 When a shock absorbing member is molded using a thermoplastic resin containing inorganic fibers, if it is designed so that it will break in the same manner as a metal shock absorbing member, the elongation of the thermoplastic resin is small, so the metal Brittle fracture occurs instead of ductile fracture like the impact absorbing member. When brittle fracture occurs, the impact load applied to the impact-absorbing member fluctuates greatly while the impact-absorbing member is broken. There was a risk of it becoming uncut.
　また、脆性的な破壊が生じた場合、破壊時に樹脂が砕けるため、飛散する破片による二次災害が発生してしまうおそれがあった。 In addition, if brittle fracture occurs, the resin will break at the time of fracture, so there is a risk of secondary disasters caused by scattered fragments.
　本発明の衝撃吸収部材は、所定の板状部材を有しており、所定の板状部材では、無機繊維が厚み方向に垂直な方向に配向している。無機繊維が厚み方向に垂直な方向に配向している所定の板状部材を用いた場合、板状部材が無機繊維の配向方向につながりながら直交方向に裂ける破壊挙動が起こるため、優れた衝撃吸収性を示す。上記のような破壊挙動が起こる理由は、所定の板状部材は無機繊維が含まれた熱可塑性樹脂層が複数積層された状態に近く、所定の板状部材に衝突エネルギーが加わったときに層間剥離を起こしながら破壊が進行するためであると考えられる。また、層間剥離が生じた場合に板状部材にかかる衝撃荷重は、座屈が生じた場合に板状部材にかかる衝撃荷重と比べて安定的に推移するため、エネルギー吸収効率（衝撃吸収性）をより高めることが可能である。そして、本発明の衝撃吸収部材を用いると層間剥離を生じながら破壊するため、破壊時に樹脂が砕けず、飛散する破片を大幅に低減することが可能である。 The shock absorbing member of the present invention has a predetermined plate-like member, and inorganic fibers are oriented in a direction perpendicular to the thickness direction in the predetermined plate-like member. When using a predetermined plate-shaped member in which the inorganic fibers are oriented in a direction perpendicular to the thickness direction, the plate-shaped member breaks in the direction perpendicular to the direction of orientation of the inorganic fibers, resulting in excellent impact absorption. show gender. The reason why the above-mentioned breaking behavior occurs is that the predetermined plate-like member is close to a state in which a plurality of thermoplastic resin layers containing inorganic fibers are laminated, and when collision energy is applied to the predetermined plate-like member, the interlayer breaks down. It is considered that this is because the fracture progresses while peeling occurs. In addition, since the impact load applied to the plate member when delamination occurs changes more stably than the impact load applied to the plate member when buckling occurs, energy absorption efficiency (shock absorption) can be further increased. Further, when the impact absorbing member of the present invention is used, it is destroyed while causing delamination, so that the resin does not break at the time of destruction, and it is possible to greatly reduce the number of scattered fragments.
　なお、所定の板状部材において無機繊維が「板状部材の厚み方向に垂直な方向」とは厳密に垂直でなくてもよい。例えば、板状部材である底面部を有する衝撃吸収部材においては、厚み方向に垂直な面に対する無機繊維の平均配向角度が０～２０°であることが好ましく、板状部材である筒状部を有する衝撃吸収部材においては、筒状部の軸方向の中央部では、厚み方向に垂直な面に対する無機繊維の平均配向角度が０～３５°であることが好ましい。平均配向角度の測定方法については後述する。なお、以下では「軸方向」は、衝撃荷重によって衝撃吸収部材が圧縮変形する方向のことを指す。 It should be noted that the direction perpendicular to the thickness direction of the plate-like member does not have to be strictly perpendicular to the inorganic fibers in the given plate-like member. For example, in a shock absorbing member having a bottom portion which is a plate-like member, the average orientation angle of the inorganic fibers with respect to a plane perpendicular to the thickness direction is preferably 0 to 20°. In the impact-absorbing member, the average orientation angle of the inorganic fibers with respect to the plane perpendicular to the thickness direction is preferably 0 to 35° in the central portion in the axial direction of the cylindrical portion. A method for measuring the average orientation angle will be described later. In addition, hereinafter, the “axial direction” refers to the direction in which the shock absorbing member is compressed and deformed by the shock load.
　また、所定の板状部材では、無機繊維が板状部材の厚み方向に垂直な方向に沿った面内での配向がランダムである。「面内での配向がランダム配向」とは、擬似等方性を意味し、板状部材の厚み方向に垂直な方向に沿った無機繊維の面内配向パラメータ（ｃｏｓ2θｙ／ｃｏｓ2θｘ）が０．６７より大きく１．５より小さいことが好ましく、０．７５以上１．３３以下であることがより好ましい。上記面内配向パラメータが１の場合、炭素繊維は面内方向に完全にランダムに配向していることを意味し、上記面内配向パラメータが上記の範囲を外れると、面内方向における繊維配向のランダム性が損なわれ、その結果、衝撃吸収性が低下するおそれがある。面内配向パラメータは以下のように測定しており、後述の実施例で用いられる板状部材（衝撃吸収部材の底面部及び筒状部）は、いずれも面内配向パラメータが０．６７より大きく１．５より小さくなっている。なお、面内配向パラメータは、無機繊維ごとにｃｏｓ2θｘ及びｃｏｓ2θｙを算出し、ｃｏｓ2θｙの平均値をｃｏｓ2θｘの平均値で除した値を面内配向パラメータ（ｃｏｓ2θｙ／ｃｏｓ2θｘ）とする。 Further, in a given plate-like member, the inorganic fibers are randomly oriented in the plane along the direction perpendicular to the thickness direction of the plate-like member. The term “in-plane orientation is random orientation” means pseudo-isotropy, and the in-plane orientation parameter (cos 2 θy/cos 2 θx) of the inorganic fibers along the direction perpendicular to the thickness direction of the plate member is preferably greater than 0.67 and less than 1.5, more preferably 0.75 or more and 1.33 or less. When the in-plane orientation parameter is 1, it means that the carbon fibers are completely randomly oriented in the in-plane direction. Randomness is impaired, and as a result, there is a risk that impact absorption will be reduced. The in-plane orientation parameter is measured as follows, and the plate-like members (bottom portion and cylindrical portion of the shock absorbing member) used in the examples described later all have an in-plane orientation parameter of greater than 0.67. is smaller than 1.5. The in-plane orientation parameter is obtained by calculating cos 2 θx and cos 2 θy for each inorganic fiber, and dividing the average value of cos 2 θy by the average value of cos 2 θx to obtain the in-plane orientation parameter (cos 2 θy/ cos 2 θx).
＜面内配向パラメータ測定方法＞
　板状部材から１５ｍｍ×２５ｍｍ程度の試験片を５枚切り出し、各試験片に対して三次元Ｘ線ＣＴ測定を行った。板状部材の面内方向にＸ軸とＹ軸、板厚方向がＺ軸となるように直交座標を決定し、Ｘ軸方向の長さを１５ｍｍ、Ｙ軸方向の長さを２５ｍｍとして試験片を切り出した。ヤマト科学社製三次元計測Ｘ線ＣＴ装置（ＴＤＭ１０００－ＩＳ）を使用し、加速電圧４０～６０ｋＶ、管電流１０～４０μＡ、積算時間０．５～１秒の条件で、０．５度ないしそれ以下の角度おきに３６０度回転させてデータ収集を行い、１画素のサイズが５０μｍないしそれ以下になるような条件で再構成を行った。得られた再構成データから、１５ｍｍ×１５ｍｍ×板状部材の板厚の領域のデータのみ抽出して、ラトックシステムエンジニアリング製のソフト「Ｔｒｉ３Ｄ　ＢＯＮ」の異方性計測機能を用いて、面内配向パラメータを算出した。 <In-plane orientation parameter measurement method>
Five test pieces of about 15 mm×25 mm were cut out from the plate member, and three-dimensional X-ray CT measurement was performed on each test piece. Orthogonal coordinates are determined so that the in-plane direction of the plate-like member is the X-axis and the Y-axis, and the plate thickness direction is the Z-axis. was cut out. Using a three-dimensional measurement X-ray CT device (TDM1000-IS) manufactured by Yamato Scientific Co., Ltd., under the conditions of an acceleration voltage of 40 to 60 kV, a tube current of 10 to 40 μA, and an integration time of 0.5 to 1 second, the temperature is 0.5 degrees or more. Data was collected by rotating 360 degrees at the following angles, and reconstruction was performed under the condition that the size of one pixel was 50 μm or less. From the obtained reconstruction data, only the data of the area of 15 mm × 15 mm × plate thickness of the plate-shaped member is extracted, and the in-plane orientation is determined using the anisotropic measurement function of the software "Tri3D BON" manufactured by Ratoc System Engineering. parameters were calculated.
＜熱可塑性樹脂テープ＞
　前記熱可塑性樹脂テープの長さは１０～１００ｍｍであることが好ましく、２０～５０ｍｍであることがより好ましい。長さが１０ｍｍ未満の場合、上述の層間剥離を発現することが困難となるおそれがあり、１００ｍｍを超える場合、成形の際の流動性が悪くなるおそれがある。 <Thermoplastic resin tape>
The thermoplastic resin tape preferably has a length of 10 to 100 mm, more preferably 20 to 50 mm. If the length is less than 10 mm, it may be difficult to develop the above-described delamination, and if it exceeds 100 mm, the fluidity during molding may deteriorate.
　前記熱可塑性樹脂テープの幅は５～５０ｍｍであることが好ましく、１０～４０ｍｍであることがより好ましい。幅が上記範囲外となると生産効率が悪くなるおそれがある。 The width of the thermoplastic resin tape is preferably 5 to 50 mm, more preferably 10 to 40 mm. If the width is out of the above range, the production efficiency may deteriorate.
　前記熱可塑性樹脂テープの厚みは０．０５～０．３ｍｍであることが好ましく、０．０７～０．２ｍｍであることがより好ましい。厚みが０．０５ｍｍ未満であると生産効率が悪くなるおそれがあり、０．３ｍｍを超えると熱可塑性樹脂の無機繊維への含浸性が不十分となるおそれがある。 The thickness of the thermoplastic resin tape is preferably 0.05-0.3 mm, more preferably 0.07-0.2 mm. If the thickness is less than 0.05 mm, production efficiency may deteriorate, and if it exceeds 0.3 mm, impregnation of the inorganic fibers with the thermoplastic resin may become insufficient.
＜熱可塑性樹脂＞
　前記熱可塑性樹脂は、特に限定されず、例えば、ナイロン６、ナイロン１１、ナイロン６６、ナイロン４６などのポリアミド系樹脂；ポリエチレンテレフタレート、ポリブチレンテレフタレートなどのポリエステル系樹脂；ポリエチレン、ポリプロピレンなどのポリオレフィン系樹脂；ポリエーテルケトン樹脂；ポリフェニレンサルファイド樹脂；ポリエーテルイミド樹脂；ポリカーボネート樹脂などが挙げられ、ポリアミド系樹脂又はポリオレフィン系樹脂であることが好ましい。熱可塑性樹脂として、前記各例示の樹脂の変性体を用いてもよい。熱可塑性樹脂は、１種でもよいし、２種以上含んでいてもよい。 <Thermoplastic resin>
The thermoplastic resin is not particularly limited, and examples include polyamide resins such as nylon 6, nylon 11, nylon 66, and nylon 46; polyester resins such as polyethylene terephthalate and polybutylene terephthalate; polyolefin resins such as polyethylene and polypropylene. polyether ketone resins; polyphenylene sulfide resins; polyetherimide resins; and polycarbonate resins. As the thermoplastic resin, modified resins of the resins exemplified above may be used. One kind of thermoplastic resin may be used, or two or more kinds thereof may be contained.
　前記熱可塑性樹脂の変性体は、例えば、酸変性体であってもよい。酸変性熱可塑性樹脂は、酸変性基が導入されている。酸変性基の種類は特に限定されず、酸変性基は１種のみでもよく、２種以上を含んでもよいが、無水カルボン酸残基（－ＣＯ－Ｏ－ＯＣ－）又はカルボン酸残基（－ＣＯＯＨ）であることが好ましい。酸変性基はどのような化合物により導入されたものであってもよく、無水カルボン酸としては、無水マレイン酸、無水イタコン酸などの不飽和カルボン酸無水物が挙げられ、カルボン酸としては、マレイン酸、イタコン酸、フマル酸などの不飽和多価カルボン酸；コハク酸、グルタル酸、アジピン酸などの飽和多価カルボン酸；アクリル酸、メタクリル酸などの不飽和モノカルボン酸などが挙げられ、中でも、不飽和カルボン酸無水物であることが好ましい。不飽和カルボン酸又は不飽和カルボン酸無水物はラジカル重合性モノマーとして使用することで熱可塑性樹脂を変性できる。多価カルボン酸は重縮合モノマーとして使用することで熱可塑性樹脂を変性できる。なお、本明細書では「熱可塑性樹脂」は酸変性熱可塑性樹脂などの熱可塑性樹脂の変性体も包含するものとする。 The modified material of the thermoplastic resin may be, for example, an acid modified material. The acid-modified thermoplastic resin has an acid-modified group introduced therein. The type of acid-modifying group is not particularly limited, and only one type of acid-modifying group may be included, or two or more types may be included. —COOH). The acid-modifying group may be introduced by any compound. Examples of carboxylic anhydrides include unsaturated carboxylic anhydrides such as maleic anhydride and itaconic anhydride. unsaturated polycarboxylic acids such as acid, itaconic acid and fumaric acid; saturated polycarboxylic acids such as succinic acid, glutaric acid and adipic acid; unsaturated monocarboxylic acids such as acrylic acid and methacrylic acid; , unsaturated carboxylic acid anhydride. Unsaturated carboxylic acids or unsaturated carboxylic acid anhydrides can be used as radically polymerizable monomers to modify thermoplastic resins. A polyvalent carboxylic acid can modify a thermoplastic resin by using it as a polycondensation monomer. In this specification, the term "thermoplastic resin" includes modified thermoplastic resins such as acid-modified thermoplastic resins.
　本発明で用いられる熱可塑性樹脂は、取り扱いやすさ、コストの観点より、ポリアミド系樹脂、ポリオレフィン系樹脂、酸変性ポリオレフィン系樹脂の少なくとも一種を含むことが好ましく、無機繊維との界面接着性向上による熱可塑性樹脂成形体の強度向上の観点から酸変性ポリオレフィン系樹脂であることが好ましい。また、本発明で用いられる熱可塑性樹脂には、必要に応じて、物性改良、成形性改良、耐久性改良を目的として、結晶核剤、熱劣化防止剤、酸化劣化防止剤、紫外線吸収剤などの添加剤を含有してもよい。これらの添加剤の含有量は、目的に応じて変化し得るが、熱可塑性樹脂１００質量％に対して、添加剤の含有量の合計が５質量％以下であるのが好ましく、２質量％以下であるのがより好ましく、１質量％以下であるのがさらに好ましい。 From the viewpoint of ease of handling and cost, the thermoplastic resin used in the present invention preferably contains at least one of polyamide resin, polyolefin resin, and acid-modified polyolefin resin. From the viewpoint of improving the strength of the thermoplastic resin molded article, it is preferably an acid-modified polyolefin resin. In addition, the thermoplastic resin used in the present invention may optionally contain a crystal nucleating agent, a heat deterioration inhibitor, an oxidation deterioration inhibitor, an ultraviolet absorber, etc. for the purpose of improving physical properties, improving moldability, and improving durability. may contain additives. The content of these additives may vary depending on the purpose, but the total content of the additives is preferably 5% by mass or less, and 2% by mass or less, relative to 100% by mass of the thermoplastic resin. and more preferably 1% by mass or less.
　本発明で用いられる熱可塑性樹脂は、温度２３０℃、荷重２．１６ｋｇで測定したときのメルトフローレートが１５～１００ｇ／１０分であることが好ましく、３０～８０ｇ／１０分であることがより好ましく、４０～６０ｇ／１０分であることがさらに好ましい。温度２３０℃、荷重２．１６ｋｇで測定したときのメルトフローレートが１５ｇ／１０分より低いと、無機繊維への熱可塑性樹脂の含浸性が不十分となり、衝撃吸収性が低下してしまうおそれがある。一方、温度２３０℃、荷重２．１６ｋｇで測定したときのメルトフローレートが１００ｇ／１０分を超えると、熱可塑性樹脂の分子量が低く熱可塑性樹脂の靭性が低下してしまうため、衝撃吸収性が低下してしまうおそれがある。なお、本明細書では、樹脂のメルトフローレートのことを「ＭＦＲ」ということがあり、ＭＦＲはＩＳＯ　１１３３－１に準拠して測定されるが、市販品を用いる場合にはカタログ等に記載の値としてもよい。また、本発明で用いられる熱可塑性樹脂テープに含まれる樹脂のＭＦＲの好ましい範囲は、本発明で用いられる熱可塑性樹脂のＭＦＲの好ましい範囲と同じである。 The thermoplastic resin used in the present invention preferably has a melt flow rate of 15 to 100 g/10 minutes, more preferably 30 to 80 g/10 minutes when measured at a temperature of 230° C. and a load of 2.16 kg. Preferably, it is 40 to 60 g/10 minutes, more preferably. If the melt flow rate is lower than 15 g/10 minutes when measured at a temperature of 230°C and a load of 2.16 kg, impregnation of the inorganic fibers with the thermoplastic resin becomes insufficient, and there is a risk that impact absorption will decrease. be. On the other hand, if the melt flow rate exceeds 100 g/10 minutes when measured at a temperature of 230 ° C. and a load of 2.16 kg, the molecular weight of the thermoplastic resin is low and the toughness of the thermoplastic resin is reduced, resulting in poor impact absorption. It is likely to decline. In this specification, the melt flow rate of the resin is sometimes referred to as "MFR", and the MFR is measured in accordance with ISO 1133-1. value. Moreover, the preferred range of MFR of the resin contained in the thermoplastic resin tape used in the present invention is the same as the preferred range of MFR of the thermoplastic resin used in the present invention.
＜無機繊維＞
　本発明で用いられる無機繊維としては、使用される熱可塑性樹脂の加工温度で固体である無機繊維であればよく、ガラス繊維及び炭素繊維の少なくとも一種を含むことが好ましく、ガラス繊維を含むことが好ましい。無機繊維は十分に開繊された無機繊維であることが好ましく、十分に開繊することにより、無機繊維への熱可塑性樹脂の含浸性を高めることができ、その結果、衝撃吸収性を高めることができる。また、単繊維を一束に集束させた無機繊維を用いていることが好ましく、集束させた無機繊維の総断面積は０．２～１．５ｍｍ2であることが好ましく、０．４～１．０ｍｍ2であることがより好ましい。 <Inorganic fiber>
The inorganic fiber used in the present invention may be any inorganic fiber that is solid at the processing temperature of the thermoplastic resin used, and preferably contains at least one of glass fiber and carbon fiber, and may contain glass fiber. preferable. The inorganic fibers are preferably sufficiently opened inorganic fibers. By sufficiently opening the inorganic fibers, the impregnation of the thermoplastic resin into the inorganic fibers can be enhanced, and as a result, the impact absorption can be enhanced. can be done. In addition, it is preferable to use inorganic fibers obtained by bundling single fibers into one bundle, and the total cross-sectional area of the bundled inorganic fibers is preferably 0.2 to 1.5 mm 2 , 0 mm 2 is more preferred.
　無機繊維は短繊維であることが好ましく、具体的には、無機繊維の平均繊維長は、５～２００ｍｍであることが好ましく、１０～１５０ｍｍであることがより好ましく、２０～１００ｍｍであることがさらに好ましく、３０～５０ｍｍであることが特に好ましい。 The inorganic fibers are preferably short fibers. Specifically, the average fiber length of the inorganic fibers is preferably 5 to 200 mm, more preferably 10 to 150 mm, and more preferably 20 to 100 mm. More preferably, it is particularly preferably 30 to 50 mm.
　無機繊維の平均繊維径は、３～３０μｍであることが好ましく、５～２０μｍであることがより好ましい。平均繊維径が３μｍ未満であると、衝撃吸収性が低下するおそれがある。平均繊維径が３０μｍを超えると、衝撃吸収部材内の無機繊維の本数が少なくなってしまい、衝撃吸収性が低下するおそれがある。 The average fiber diameter of the inorganic fibers is preferably 3-30 μm, more preferably 5-20 μm. If the average fiber diameter is less than 3 µm, there is a risk that the impact absorption will decrease. If the average fiber diameter exceeds 30 μm, the number of inorganic fibers in the impact absorbing member is reduced, which may reduce impact absorption.
　なお、無機繊維の平均繊維長及び平均繊維径は走査型電子顕微鏡（ＳＥＭ）を用いてＪＩＳ　Ｒ　３４２０に基づき測定した値を算術平均することにより求めることができる。 The average fiber length and average fiber diameter of inorganic fibers can be obtained by arithmetically averaging values measured based on JIS R 3420 using a scanning electron microscope (SEM).
（ガラス繊維）
　ガラス繊維は、特に限定されず、Ｅガラス、Ｓガラス、Ｃガラスなど、公知のガラス繊維が挙げられ、Ｅガラスであることが好ましい。ガラス繊維は、１種のみを使用してもよいし、２種以上を使用してもよい。 (glass fiber)
The glass fiber is not particularly limited, and includes known glass fibers such as E glass, S glass, and C glass, preferably E glass. Only one type of glass fiber may be used, or two or more types may be used.
（炭素繊維）
　炭素繊維としては、特に限定されず、ポリアクリロニトリル（ＰＡＮ）系炭素繊維、ピッチ系炭素繊維、レーヨン系炭素繊維、セルロース系炭素繊維、気相成長系炭素繊維、これらの黒鉛化繊維などが挙げられる。炭素繊維はＰＡＮ系炭素繊維を含むことが好ましい。ＰＡＮ系炭素繊維はポリアクリロニトリル繊維を原料とする炭素繊維である。ピッチ系炭素繊維は石油タールや石油ピッチを原料とする炭素繊維である。セルロース系炭素繊維はビスコースレーヨンや酢酸セルロースなどを原料とする炭素繊維である。気相成長系炭素繊維は炭化水素などを原料とする炭素繊維である。炭素繊維は、１種のみを使用してもよいし、２種以上を使用してもよい。 (Carbon fiber)
Carbon fibers are not particularly limited, and include polyacrylonitrile (PAN)-based carbon fibers, pitch-based carbon fibers, rayon-based carbon fibers, cellulose-based carbon fibers, vapor growth-based carbon fibers, graphitized fibers thereof, and the like. . The carbon fibers preferably contain PAN-based carbon fibers. PAN-based carbon fibers are carbon fibers made from polyacrylonitrile fibers. Pitch-based carbon fibers are carbon fibers made from petroleum tar or petroleum pitch. Cellulose-based carbon fibers are carbon fibers made from viscose rayon, cellulose acetate, or the like. Vapor-grown carbon fibers are carbon fibers made from hydrocarbons or the like. Only one type of carbon fiber may be used, or two or more types may be used.
＜無機繊維の含有率＞
　所定の板状部材における無機繊維の含有率は３０～６０体積％であり、３５～５５体積％であることが好ましく、４０～５０体積％であることがより好ましい。３０体積％未満である場合、無機繊維による板状部材の補強効果が得られず、衝突に対する衝撃吸収部材の安定性が低下してしまうため、衝撃吸収部材の破壊挙動が不安定になり、衝撃吸収性が低下してしまう。一方、６０体積％を超えると生産効率が悪くなる上に、無機繊維への熱可塑性樹脂の含浸性が不十分となり、衝撃吸収部材の破壊挙動が不安定になり、衝撃吸収性が低下してしまう。 <Inorganic fiber content>
The inorganic fiber content in a given plate member is 30 to 60% by volume, preferably 35 to 55% by volume, more preferably 40 to 50% by volume. If the content is less than 30% by volume, the effect of reinforcing the plate-shaped member by the inorganic fiber cannot be obtained, and the stability of the impact-absorbing member against collision is lowered, so the breaking behavior of the impact-absorbing member becomes unstable, and the impact absorbency is reduced. On the other hand, if it exceeds 60% by volume, the production efficiency will be poor, and the impregnation of the inorganic fiber with the thermoplastic resin will be insufficient, resulting in unstable fracture behavior of the shock absorbing member and reduced shock absorption. put away.
＜衝撃吸収部材＞
　本発明の衝撃吸収部材は、所定の板状部材で構成された筒状部を有することが好ましい。衝撃が作用する方向と筒状部の軸方向を合わせることで、効率よく衝撃を吸収できる上に、無機繊維が含まれた熱可塑性樹脂層が複数積層された状態に近く、所定の板状部材に衝突エネルギーが加わったときに層間剥離を起こしながら破壊が進行することができるため、衝突安全性をより高めることが可能である。 <Impact absorbing member>
It is preferable that the impact absorbing member of the present invention has a tubular portion formed of a predetermined plate-like member. By aligning the direction in which the impact acts with the axial direction of the cylindrical portion, it is possible to efficiently absorb the impact, and the thermoplastic resin layer containing inorganic fibers is close to a state in which multiple layers are laminated. When collision energy is applied to , the fracture progresses while causing delamination, so it is possible to further improve collision safety.
　また、衝撃吸収部材は所定の板状部材で構成された筒状部に加えて、筒状部の一方の底面を塞いだ底面部を有すると、底面部で筒状部の底面を塞ぐことで、筒状部の周方向全体に衝撃を効率よく分散させることができるため好ましい。本発明の衝撃吸収部材において、底面部は板状部材であることが好ましく、底面部は所定の板状部材であることがより好ましく、筒状部及び底面部は所定の板状部材により構成されていることがさらに好ましい。 Further, if the impact absorbing member has a bottom portion that closes one bottom surface of the tubular portion in addition to the tubular portion that is configured by a predetermined plate-shaped member, the bottom portion closes the bottom surface of the tubular portion. , because the impact can be efficiently distributed over the entire circumferential direction of the cylindrical portion. In the impact-absorbing member of the present invention, the bottom portion is preferably a plate-like member, more preferably a predetermined plate-like member, and the cylindrical portion and the bottom portion are composed of predetermined plate-like members. More preferably.
　以下、図１を参照して、衝撃吸収部材の形状について説明する。図１は、本発明の実施の形態に係る衝撃吸収部材の斜視図である。直方体状である衝撃吸収部材１１は、厚さ方向から見た形状が長方形である板状部材の底面部１２の一方の面の外周から垂直方向に延びるように４つの直方体状の筒状部１３が設けられており、底面部１２と筒状部１３によって区切られることにより、衝撃吸収部材１１の内部には４つの直方体状の内部空間１４が格子状に形成されている。すなわち、衝撃吸収部材１１の外形は、底面部１２の外周である４つの辺から底面部１２の垂直方向に板状部材が立設された形状である。なお、底面部１２及び筒状部１３によって内部空間１４が形成されているが、衝撃吸収部材１１の内部に位置する筒状部１３の板状部材は２つの内部空間１４の形成に共通して用いられている。また、４つの内部空間１４の軸方向の底面はいずれも底面部１２によって塞がれており、４つの内部空間１４の側面はいずれも筒状部１３で構成されているが、４つの内部空間１４の上面はいずれも塞がれていない。 The shape of the impact absorbing member will be described below with reference to FIG. FIG. 1 is a perspective view of a shock absorbing member according to an embodiment of the invention. The rectangular parallelepiped shock absorbing member 11 has four rectangular parallelepiped cylindrical portions 13 extending vertically from the outer circumference of one surface of a bottom surface portion 12 of a plate-like member having a rectangular shape when viewed in the thickness direction. are provided, and four rectangular parallelepiped internal spaces 14 are formed inside the impact absorbing member 11 in a grid pattern by being partitioned by the bottom surface portion 12 and the cylindrical portion 13 . That is, the outer shape of the impact absorbing member 11 is a shape in which plate-like members are erected in the vertical direction of the bottom surface portion 12 from the four sides which are the outer periphery of the bottom surface portion 12 . The inner space 14 is formed by the bottom surface portion 12 and the cylindrical portion 13, and the plate-like member of the cylindrical portion 13 positioned inside the impact absorbing member 11 is common to the formation of the two inner spaces 14. used. In addition, the bottom surfaces of the four internal spaces 14 in the axial direction are all closed by the bottom surface portion 12, and the side surfaces of the four internal spaces 14 are all constituted by the cylindrical portions 13, but the four internal spaces None of the top surfaces of 14 are blocked.
　底面部１２は、特に限定されておらず、板状、編目状、格子状の部材などが挙げられる。中でも、板状部材であることが好ましいが、筒状部１３の一方の底面を塞いでいれば底面部１２は完全に面状である必要はなく、部分的な凹凸を有していてもよい。底面部の厚さは特に限定されておらず、１～８ｍｍであることが好ましく、２～６ｍｍであることがより好ましい。なお、底面部１２の厚さとは底面部の最も薄い部分の厚さのことを指し、底面部１２の最も厚い箇所の厚さは底面部の厚さの２倍以下であることが好ましい。底面部１２の厚さ方向（衝撃吸収部材１１の軸方向）から見た形状は、特に限定されておらず、例えば、円形、楕円形、多角形などが挙げられるが、これらの形状の一部やこれらの形状の組み合わせであってもよい。エネルギー吸収領域の断面二次モーメントを大きくして効率的にエネルギーを吸収するという観点から、底面部１２の厚さ方向から見た形状は、円形、短径と長径の長さの比が０．５倍以上１倍未満である楕円形、正三角形、最短辺の長さと最長辺の長さの比が０．５倍以上１倍未満である三角形、正方形、最短辺の長さと最長辺の長さの比が０．５倍以上１倍未満である長方形、正六角形、又は最短辺の長さと最長辺の長さの比が０．５倍以上１倍未満である六角形であることが好ましい。また、底面部１２には通気、ボルト締結、配線などのための貫通口が形成されていてもよい。この場合、衝撃吸収部材の成形と同時に型内でシャーなどを用いて開孔させてもよく、後加工としてドリル、打ち抜き、切削加工などで開孔させてもよい。 The bottom part 12 is not particularly limited, and may be a plate-like, mesh-like, lattice-like member, or the like. Among them, a plate-like member is preferable, but the bottom surface portion 12 does not need to be completely planar as long as it covers one bottom surface of the cylindrical portion 13, and may have partial unevenness. . The thickness of the bottom portion is not particularly limited, and is preferably 1 to 8 mm, more preferably 2 to 6 mm. The thickness of the bottom portion 12 refers to the thickness of the thinnest portion of the bottom portion 12, and the thickness of the thickest portion of the bottom portion 12 is preferably twice or less than the thickness of the bottom portion. The shape of the bottom portion 12 viewed from the thickness direction (the axial direction of the shock absorbing member 11) is not particularly limited, and examples thereof include circular, elliptical, and polygonal shapes, but some of these shapes are possible. or a combination of these shapes. From the viewpoint of increasing the geometrical moment of inertia of the energy absorbing region to efficiently absorb energy, the shape of the bottom portion 12 viewed from the thickness direction is circular, and the ratio of the length of the minor axis to the major axis is 0.5. Ellipses and equilateral triangles that are 5 times or more and less than 1 time, triangles and squares that have a ratio of the length of the shortest side to the length of the longest side of 0.5 times or more and less than 1 time, and the length of the shortest side and the length of the longest side It is preferably a rectangle, a regular hexagon, or a hexagon with a ratio of length of the shortest side to length of the longest side of 0.5 times or more and less than 1 time. . Further, the bottom portion 12 may be formed with through holes for ventilation, bolt fastening, wiring, and the like. In this case, the holes may be formed by using a shear or the like in the mold at the same time as the impact absorbing member is molded, or may be formed by drilling, punching, cutting, or the like as post-processing.
　筒状部１３は底面部１２から底面部１２の底面に垂直な方向（底面部の厚み方向）に伸びるように設けられており、筒状部１３は板状部材であることが好ましい。筒状部１３が板状部材であると、板状部材の軸方向に沿って衝突エネルギーが加わり、衝突エネルギーの大きさが板状部材での限界値を超えた段階で板状部材が変形して衝撃を吸収することになり、衝撃エネルギーが効率的に吸収される。また、衝突エネルギーを効率的に吸収する観点から、筒状部１３の高さはいずれも全て同じ高さであることが好ましい。 The cylindrical portion 13 is provided so as to extend from the bottom surface portion 12 in a direction perpendicular to the bottom surface of the bottom surface portion 12 (thickness direction of the bottom surface portion), and the cylindrical portion 13 is preferably a plate-like member. If the tubular portion 13 is a plate-like member, collision energy is applied along the axial direction of the plate-like member, and the plate-like member deforms when the magnitude of the collision energy exceeds the limit value of the plate-like member. The impact energy is efficiently absorbed. Moreover, from the viewpoint of efficiently absorbing collision energy, it is preferable that all the heights of the cylindrical portions 13 are the same.
　また、筒状部１３は、衝突エネルギーを効率的に吸収する観点から、底面部１２の外周の少なくとも一部から底面部１２の垂直方向に板状部材が立設された形状であることが好ましく、底面部１２の外周全体から底面部１２の垂直方向に筒状の部材が立設された形状であることがより好ましいが、衝突エネルギーの吸収量を調節するために、底面部１２の外周よりも内側の位置から底面部１２の垂直方向に板状部材が立設された形状であってもよい。 In addition, from the viewpoint of efficiently absorbing collision energy, the cylindrical portion 13 preferably has a shape in which a plate-like member is erected in a direction perpendicular to the bottom portion 12 from at least a part of the outer periphery of the bottom portion 12. It is more preferable to have a cylindrical member erected vertically from the entire outer circumference of the bottom surface portion 12, but in order to adjust the amount of collision energy absorption, A plate-like member may be erected vertically from the inner side of the bottom surface portion 12 .
　筒状部１３の高さは特に限定されないが、底面部１２の厚さ方向から見た形状が円形、楕円形、正三角形、正方形、長方形、正六角形、又は六角形である場合、底面部１２の最短辺又は短径に対して、０．５～３倍であることが好ましく、０．６～２倍であることがより好ましく、０．６５～１．５倍であることがさらに好ましい。筒状部１３の高さが底面部１２の最短辺又は短径に対して０．５倍よりも小さい場合、筒状部１３に衝突エネルギーが加わり破壊や変形を行おうとしたときに、破壊や変形ができる空間が不十分であり、衝撃吸収部材１１の破壊挙動が不安定になり、衝撃吸収性が低下してしまうおそれがある。一方、底面部１２の最短辺又は短径に対して３倍よりも大きい場合、衝撃荷重が加わったときに座屈が生じる可能性が高くなったり、成形時の成形圧力を高く設定する必要があるため、成形コストが高くなったりしてしまうおそれがある。 The height of the tubular portion 13 is not particularly limited, but when the bottom portion 12 has a circular, elliptical, equilateral triangle, square, rectangular, regular hexagonal, or hexagonal shape when viewed from the thickness direction, the bottom portion 12 It is preferably 0.5 to 3 times, more preferably 0.6 to 2 times, and even more preferably 0.65 to 1.5 times the shortest side or minor axis of . If the height of the cylindrical portion 13 is less than 0.5 times the shortest side or minor axis of the bottom portion 12, collision energy will be applied to the cylindrical portion 13 to cause destruction or deformation. The space for deformation is insufficient, and the breaking behavior of the impact absorbing member 11 becomes unstable, which may lead to a decrease in impact absorption. On the other hand, if it is more than three times the shortest side or minor axis of the bottom surface portion 12, the possibility of buckling when an impact load is applied increases, or it becomes necessary to set a high molding pressure during molding. Therefore, the molding cost may increase.
　筒状部１３は、底面部１２の底面に垂直な方向に設けられることが好ましいが、衝撃吸収性が確保できるのであれば、厳密に垂直でなくともよい。この場合、底面部１２と筒状部１３との角度は３０～１２０°であることが好ましく、４０～９０°であることがより好ましい。なお、筒状部１３には、本発明の意図を損なわない程度に、金型の抜き勾配を確保するための角度を設けてもよい。 The cylindrical part 13 is preferably provided in a direction perpendicular to the bottom surface of the bottom part 12, but it does not have to be strictly perpendicular as long as the shock absorption can be ensured. In this case, the angle between the bottom portion 12 and the tubular portion 13 is preferably 30 to 120°, more preferably 40 to 90°. The cylindrical portion 13 may be provided with an angle for securing the draft angle of the mold to the extent that the intention of the present invention is not impaired.
　筒状部１３の厚さに特に制限はなく、底面部１２の厚さと同じであってもよく、異なっていてもよいが、１～８ｍｍが好ましく、２～６ｍｍがより好ましい。 The thickness of the cylindrical portion 13 is not particularly limited, and may be the same as or different from the thickness of the bottom portion 12, preferably 1 to 8 mm, more preferably 2 to 6 mm.
　本発明の衝撃吸収部材において、筒状部１３により、筒状部１３の軸方向（底面部１２の厚み方向）から見て２つ以上の閉断面構造が形成されていることが好ましい。閉断面構造としては、特に限定されないが、衝突エネルギーを効率的に吸収する観点から、線対称又は点対象である形状であることが好ましく、例えば、円形、楕円形、多角形、又はこれらの形状の一部の組み合わせなどが挙げられるが、三角形、長方形、正方形、又は六角形であれば、内部空間１４が隙間なく並ぶ形状とすることができるため、好ましい。 In the impact absorbing member of the present invention, it is preferable that the tubular portion 13 forms two or more closed cross-sectional structures when viewed from the axial direction of the tubular portion 13 (thickness direction of the bottom surface portion 12). The closed cross-sectional structure is not particularly limited, but from the viewpoint of efficiently absorbing collision energy, it preferably has a line-symmetrical or point-symmetrical shape, such as a circular shape, an elliptical shape, a polygonal shape, or any of these shapes. However, a triangular, rectangular, square, or hexagonal shape is preferable because the internal spaces 14 can be arranged without gaps.
　筒状部における無機繊維の含有率と底面部における無機繊維の含有率との差が５体積％以下であることが好ましく、３体積％以下であることがより好ましく、２体積％以下であることがさらに好ましく、１．５体積％以下であることが特に好ましい。５体積％を超えると衝突エネルギー（応力）の集中点が想定とは異なる箇所で生じ、衝撃吸収性が低下するおそれがある。また、ＧＭＴ（Ｇｌａｓｓ　Ｍａｔ　ｒｅｉｎｆｏｒｃｅｄ　Ｔｈｅｒｍｏｐｌａｓｔｉｃｓ）のような市販のスタンパブルシートを用いた場合、５体積％を超える上に、筒状部の先端では他の部位より無機繊維の含有率が低い樹脂リッチな状態となり、衝突時に衝撃吸収部材が粉々に砕けながら破壊が進行してしまったり、衝撃吸収部材の伸度が高くなることにより、金属製の衝撃吸収部材を用いたときの破壊挙動と同様の座屈のような変形が起こり、衝撃吸収部材が折れてしまったりする。なお、複数の内部空間を有する衝撃吸収部材では、「筒状部における無機繊維の含有率と底面部における無機繊維の含有率との差」とは、最外周に位置する筒状部の軸方向の先端部における無機繊維の含有率と最外周以外の筒状部の軸方向の先端部における無機繊維の含有率とを測定し、底面部における無機繊維の含有率との差の絶対値が大きい方の値とする。また、底面部については、筒状部と接合している箇所から最も離れた箇所（例えば図１の衝撃吸収部材では図４の斜線部分（測定部位４１））の無機繊維の含有率を測定する。 The difference between the inorganic fiber content in the cylindrical portion and the inorganic fiber content in the bottom portion is preferably 5% by volume or less, more preferably 3% by volume or less, and 2% by volume or less. is more preferable, and 1.5% by volume or less is particularly preferable. If the content exceeds 5% by volume, the impact energy (stress) concentration point may occur at an unexpected location, resulting in a decrease in impact absorption. In addition, when a commercially available stampable sheet such as GMT (Glass Mat reinforced Thermoplastics) is used, the content exceeds 5% by volume, and the tip of the cylindrical portion is resin-rich with a lower inorganic fiber content than the other portions. At the time of collision, the shock absorbing member shatters into small pieces as the fracture progresses, or the elongation of the shock absorbing member increases, resulting in the same fracture behavior as when using a metal shock absorbing member. A bending-like deformation occurs, and the shock absorbing member breaks. In addition, in the impact absorbing member having a plurality of internal spaces, the "difference between the inorganic fiber content rate in the cylindrical portion and the inorganic fiber content rate in the bottom portion" refers to the axial direction of the outermost cylindrical portion. Measure the inorganic fiber content at the tip and the inorganic fiber content at the tip in the axial direction of the cylindrical portion other than the outermost periphery, and the absolute value of the difference between the inorganic fiber content at the bottom is large value. As for the bottom part, the content of inorganic fibers is measured at the part farthest from the part joined to the cylindrical part (for example, the hatched part (measurement part 41) in FIG. 4 for the shock absorbing member in FIG. 1). .
　図２は、本発明の実施の形態に係る衝撃吸収部材の変形例の斜視図である。直方体の形状である衝撃吸収部材２１は、厚さ方向から見た形状が長方形である板状部材の底面部２２の一方の面から垂直方向に六角柱状の筒状部２３がハニカム構造となるように設けられている。底面部２２と筒状部２３によって区切られることにより、衝撃吸収部材２１の内部には４つの六角柱状の内部空間２４がハニカム構造となるように設けられているが、衝撃吸収部材２１の軸方向の外周近傍では内部空間２５のように六角柱の一部の形状となっている箇所もある。また、衝撃吸収部材２１の外形は、底面部２２の外周である４つの辺から底面部２２の垂直方向に板状部材が立設された形状である。なお、筒状部２３によって内部空間２４及び２５が形成されているが、衝撃吸収部材２１の内部に位置する筒状部２３の板状部材は２つの内部空間２４の形成、内部空間２４及び内部空間２５の形成、又は２つの内部空間２５の形成に共通して用いられている。また、内部空間２４及び２５の軸方向の底面は底面部２２によって塞がれており、側面はいずれも筒状部２３で構成されているが、上面は塞がれていない。 FIG. 2 is a perspective view of a modification of the shock absorbing member according to the embodiment of the invention. The impact absorbing member 21 having a rectangular parallelepiped shape is a plate-like member having a rectangular shape when viewed from the thickness direction. is provided in Four hexagonal prism-shaped internal spaces 24 are provided inside the shock absorbing member 21 so as to form a honeycomb structure by being partitioned by the bottom surface portion 22 and the tubular portion 23 , but are arranged in the axial direction of the shock absorbing member 21 . In the vicinity of the outer periphery of the , there is also a part, such as the internal space 25, which is shaped like a part of a hexagonal column. Further, the outer shape of the impact absorbing member 21 is a shape in which plate-like members are erected in the vertical direction of the bottom surface portion 22 from the four sides which are the outer periphery of the bottom surface portion 22 . The cylindrical portion 23 defines the internal spaces 24 and 25, and the plate-like member of the cylindrical portion 23 located inside the impact absorbing member 21 forms two internal spaces 24, the internal space 24 and the internal space. It is commonly used to form the space 25 or to form two internal spaces 25 . Further, the axial bottom surfaces of the internal spaces 24 and 25 are closed by the bottom surface portion 22, and the side surfaces are both formed by the tubular portion 23, but the upper surfaces are not closed.
　図３は、本発明の実施の形態に係る衝撃吸収部材のさらなる変形例の斜視図である。衝撃吸収部材３１は、厚さ方向から見た形状が長方形である板状部材の底面部３２の中央部において、底面部３２の一方の面から垂直方向に延びるように４つの円筒状の筒状部３３が設けられている。底面部３２と筒状部３３によって筒状部３３同士の間に出来る隙間（後述の内部空間３５）が最小限となるように形成されており、３つの隣接した内部空間３４で囲まれるように内部空間３５が形成されている。なお、内部空間３４及び３５の軸方向の底面は底面部３２によって塞がれており、側面はいずれも筒状部３３で構成されているが、上面は塞がれていない。 FIG. 3 is a perspective view of a further modified example of the impact absorbing member according to the embodiment of the present invention. The impact absorbing member 31 has four cylindrical tubular members extending vertically from one surface of the bottom surface portion 32 at the central portion of the bottom surface portion 32 of a plate-like member having a rectangular shape when viewed in the thickness direction. A portion 33 is provided. The bottom portion 32 and the tubular portion 33 are formed so that a gap (internal space 35 to be described later) created between the tubular portions 33 is minimized, and is surrounded by three adjacent internal spaces 34 . An internal space 35 is formed. The axial bottom surfaces of the internal spaces 34 and 35 are closed by the bottom surface portion 32, and the side surfaces are both formed by the tubular portion 33, but the upper surfaces are not closed.
＜衝撃吸収部材の製造方法＞
　本発明の衝撃吸収部材の製造方法は、衝撃吸収部材に含まれる所定の板状部材において無機繊維の配向方向が上述の所定の要件を満たし、かつ、所定の板状部材における無機繊維の含有率が範囲内である限り、特に限定されないが、例えば、開繊された無機繊維ロービングと熱可塑性樹脂とを用いて比較的薄い厚さの熱可塑性樹脂シートを製造し、次に熱可塑性樹脂シートをカッティングすることにより熱可塑性樹脂テープを得て、その後、カッティングした熱可塑性樹脂テープを用いて比較的厚い熱可塑性樹脂シートを作製し、最後に厚い熱可塑性樹脂シートを金型内に投入して成形することにより所望の形状の衝撃吸収部材を得ることが好ましい。なお、以下では、「無機繊維を含有する」という記載を省略し、単に「熱可塑性樹脂テープ」と記載し、上記の比較的薄い熱可塑性樹脂シートを「薄型熱可塑性樹脂シート」といい、上記の比較的厚い熱可塑性樹脂シートを「厚型熱可塑性樹脂シート」ということがある。以下に上記製造方法の各工程における詳細を説明する。 <Method for manufacturing shock absorbing member>
In the method for manufacturing a shock absorbing member of the present invention, the direction of orientation of inorganic fibers in a predetermined plate-like member included in the shock absorbing member satisfies the above-described predetermined requirements, and the content of inorganic fibers in the predetermined plate-like member is is within the range. A thermoplastic resin tape is obtained by cutting, then a relatively thick thermoplastic resin sheet is produced using the cut thermoplastic resin tape, and finally the thick thermoplastic resin sheet is put into a mold for molding. It is preferable to obtain an impact absorbing member having a desired shape by doing so. In the following, the description of "containing inorganic fibers" will be omitted and simply referred to as "thermoplastic resin tape", and the relatively thin thermoplastic resin sheet will be referred to as "thin thermoplastic resin sheet". A relatively thick thermoplastic resin sheet is sometimes referred to as a "thick thermoplastic resin sheet". The details of each step of the above manufacturing method will be described below.
　無機繊維のロービングを開繊し、開繊された無機繊維のロービングを加熱溶融された熱可塑性樹脂が溜められた槽（以下、樹脂含浸槽という）の中に導入して、熱可塑性樹脂を無機繊維のロービングに連続的に含浸させる。開繊された無機繊維のロービングに樹脂を含浸させた後、賦形ローラーで潰し冷却固化させることにより、薄型熱可塑性樹脂シートを作製することができる。そして、薄型熱可塑性樹脂シートはファンカッターなどのカッターによって切断され、薄型熱可塑性樹脂シートが製造される。 An inorganic fiber roving is opened, and the opened inorganic fiber roving is introduced into a tank (hereinafter referred to as a resin impregnation tank) in which heat-melted thermoplastic resin is stored, and the thermoplastic resin is impregnated with an inorganic A roving of fibers is continuously impregnated. A thin thermoplastic resin sheet can be produced by impregnating an open inorganic fiber roving with a resin, crushing it with a shaping roller, and solidifying it by cooling. Then, the thin thermoplastic resin sheet is cut by a cutter such as a fan cutter to produce a thin thermoplastic resin sheet.
　開繊工程は、無機繊維を引き揃え、そして十分に開繊させて用いることが好ましい。撚りが殆ど入らない状態で行われるのが望ましく、通常、ローラー及び空気開繊工程が用いられるが、これに限定されるものではない。熱可塑性樹脂を連続的に効率良く含浸させるため、樹脂に０．１ＭＰａの圧力をかける（０．１ＭＰａ以上の圧力を有する樹脂含浸槽を通す）のが好ましい。０．１ＭＰａ未満である場合、含浸性が十分に得られにくくなる。樹脂含浸槽内の圧力は高い方がより含浸性が向上し好ましく、より好ましくは０．３ＭＰａ以上、さらに好ましくは０．５ＭＰａ以上である。樹脂含浸槽内の圧力は高い方がより含浸性が向上し好ましいが、設備コストも高くなるので、２ＭＰａ以下であることが好ましい。 In the fiber opening process, it is preferable to use the inorganic fibers after aligning and sufficiently opening them. It is desirable to do so in a state in which there is little twisting, and roller and air opening processes are usually used, but are not limited to these. In order to continuously and efficiently impregnate the thermoplastic resin, it is preferable to apply a pressure of 0.1 MPa to the resin (pass it through a resin impregnation bath having a pressure of 0.1 MPa or more). When it is less than 0.1 MPa, it becomes difficult to obtain sufficient impregnation. The higher the pressure in the resin impregnation bath, the better the impregnation performance, and the more preferably the pressure is 0.3 MPa or more, and the more preferably 0.5 MPa or more. The higher the pressure in the resin impregnation tank, the better the impregnability, which is preferable.
　樹脂含浸槽を通過した無機繊維は、引取り張力により集束し易く、この状態では無機繊維の細部に熱可塑性樹脂が含浸しきれていない。そのため、賦形ローラーで潰し冷却固化させ熱可塑性樹脂テープを作製することにより、樹脂含浸性と取り扱い性とを向上させることが出来る。 The inorganic fibers that have passed through the resin impregnation tank tend to be bundled together due to the pulling tension, and in this state, the details of the inorganic fibers are not completely impregnated with the thermoplastic resin. Therefore, resin impregnability and handleability can be improved by crushing with a shaping roller and solidifying by cooling to produce a thermoplastic resin tape.
　厚型熱可塑性樹脂シートは、上記のようにして得られた熱可塑性樹脂テープをランダムにばらまいて、積層させ、予め熱可塑性樹脂の融点以上に温度調整した金型をセットした圧縮成型機を使用して圧縮し、金型を冷却した後、型開きを行うことで得ることができる。 The thick thermoplastic resin sheet is made by randomly scattering the thermoplastic resin tapes obtained as described above, laminating them, and using a compression molding machine in which a mold whose temperature has been adjusted to the melting point or higher of the thermoplastic resin is set. It can be obtained by compressing, cooling the mold, and opening the mold.
　熱可塑性樹脂テープをランダムにばらまいて、積層させて、厚型熱可塑性樹脂シートを作製しているため、無機繊維が厚型熱可塑性樹脂シートの厚み方向に垂直な方向に配向しており、かつ、無機繊維が厚型熱可塑性樹脂シートの平面方向に配向していると共に、平面方向と直交する方向での配向がランダムとなっている。このような厚型熱可塑性樹脂シートを用いて後述のプレス成形を行うと、無機繊維が板状部材の厚み方向に垂直な方向に配向していると共に、該垂直方向に沿った面内での無機繊維の配向がランダムとなる板状部材を成形することができる。そして、このような板状部材を有する衝撃吸収部材を用いると、衝突エネルギーが加わったときに層間剥離を起こしながら破壊が進行することとなり、衝突安全性を高めることができる。 Since the thermoplastic resin tapes are randomly scattered and laminated to produce a thick thermoplastic resin sheet, the inorganic fibers are oriented in a direction perpendicular to the thickness direction of the thick thermoplastic resin sheet, and , the inorganic fibers are oriented in the planar direction of the thick thermoplastic resin sheet, and the orientation in the direction orthogonal to the planar direction is random. When press molding described later is performed using such a thick thermoplastic resin sheet, the inorganic fibers are oriented in a direction perpendicular to the thickness direction of the plate-like member, and in-plane along the perpendicular direction. It is possible to mold a plate-like member in which the inorganic fibers are randomly oriented. When a shock absorbing member having such a plate-like member is used, delamination occurs when collision energy is applied, and destruction progresses, so that collision safety can be improved.
　厚型熱可塑性樹脂シートの成形をするに際し、金型温度は熱可塑性樹脂の固化温度以下であることが好ましく、固化温度－６０℃～固化温度－１０℃であることが好ましい。金型温度は高いほうが厚型熱可塑性樹脂シートの成形性は高まるが、厚型熱可塑性樹脂シートのソリを防ぐためには金型温度は低いほうがよい。 When molding a thick thermoplastic resin sheet, the mold temperature is preferably below the solidification temperature of the thermoplastic resin, preferably from -60°C to -10°C. The higher the mold temperature, the higher the moldability of the thick thermoplastic resin sheet, but the lower the mold temperature, the better in order to prevent warping of the thick thermoplastic resin sheet.
　また、厚型熱可塑性樹脂シートの成形をするに際し、プレス圧力は０．１ＭＰａ以上であることが好ましく、１ＭＰａ以上であることがより好ましい。０．１ＭＰａより小さくすると熱可塑性樹脂テープに十分に圧力がかからず、気泡ができたり、表面品位が悪くなったりするおそれがある。厚型熱可塑性樹脂シート成形の際、プレス圧力は高いほうがよりシート品位が高くなるため好ましいが、設備コストが高くなってしまうため、１０ＭＰａ以下であることが好ましい。プレス保持時間は０．５～２０分であることが好ましく、１～１０分であることがより好ましい。 Also, when molding the thick thermoplastic resin sheet, the press pressure is preferably 0.1 MPa or more, more preferably 1 MPa or more. If the pressure is less than 0.1 MPa, sufficient pressure is not applied to the thermoplastic resin tape, and air bubbles may be generated or the surface quality may be deteriorated. When molding a thick thermoplastic resin sheet, a higher press pressure is preferable because the quality of the sheet is higher. The press holding time is preferably 0.5 to 20 minutes, more preferably 1 to 10 minutes.
　熱可塑性樹脂シートを用いて本発明の衝撃吸収部材を作製するために行う成形方法としては、プレス成形が好ましい。プレス成形としては、ヒート＆クール成形法やスタンピング成形法などが挙げられるが、サイクルタイムや成形コストの面からスタンピング成形法であることが好ましい。スタンピング成形は、赤外線加熱や高周波加熱により、熱可塑性樹脂シートを使用する熱可塑性樹脂の融点以上に加熱溶融し、融点以下の温度に調整された金型に供給し、腑形冷却後脱型することにより行われる成形を指す。スタンピング成形時の金型温度、プレス圧力、プレス保持時間などの成形条件については、用いる熱可塑性樹脂により適宜設定すればよいが、以下のような条件で行うことが好ましい。 Press molding is preferable as a molding method for producing the impact absorbing member of the present invention using a thermoplastic resin sheet. Examples of press molding include a heat & cool molding method and a stamping molding method, but the stamping molding method is preferred in terms of cycle time and molding cost. In stamping molding, the thermoplastic resin sheet is heated and melted to a temperature above the melting point of the thermoplastic resin using infrared heating or high-frequency heating, supplied to a mold adjusted to a temperature below the melting point, and removed from the mold after cooling. refers to the molding performed by Molding conditions such as mold temperature, press pressure, and press holding time during stamping molding may be appropriately set according to the thermoplastic resin to be used, but the following conditions are preferred.
　スタンピング成形をするに際し、金型温度は熱可塑性樹脂の固化温度以下であることが好ましく、固化温度－６０℃～固化温度－１０℃であることが好ましい。金型温度は高いほうが成形性は高まるが、成形体のソリを防ぐためには金型温度は低いほうがよい。 When performing stamping molding, the mold temperature is preferably below the solidification temperature of the thermoplastic resin, preferably from -60°C to -10°C. The higher the mold temperature, the higher the moldability, but the lower the mold temperature, the better, in order to prevent warping of the molded body.
　また、スタンピング成形をするに際し、プレス圧力は１ＭＰａ以上であることが好ましく、１０ＭＰａ以上であることがより好ましい。１ＭＰａより小さくすると熱可塑性樹脂シートに十分に圧力がかからず、流動不足による成形不良が生じたり、成形品内部に気泡が生じたりするおそれがある。スタンピング成形時のプレス圧力は高いほうがより成形品の品位が高くなるため好ましいが、設備コストが高くなってしまうため、５０ＭＰａ以下であることが好ましい。プレス保持時間は１～１０分であることが好ましく、１～５分であることがより好ましい。 Also, when performing stamping molding, the press pressure is preferably 1 MPa or more, more preferably 10 MPa or more. When the pressure is less than 1 MPa, sufficient pressure is not applied to the thermoplastic resin sheet, and there is a possibility that defective molding may occur due to insufficient flow, or air bubbles may occur inside the molded product. The higher the press pressure during stamping molding, the higher the quality of the molded product. The press holding time is preferably 1 to 10 minutes, more preferably 1 to 5 minutes.
　上記製造方法では、熱可塑性樹脂シートをカッティングすることにより熱可塑性樹脂テープが得られるため、薄型熱可塑性樹脂シートも熱可塑性樹脂テープと同等の厚みであることが好ましい。厚型熱可塑性樹脂シートの厚みは０．３５～１．２ｍｍであることが好ましく、０．５～１．０ｍｍであることがより好ましい。厚みが０．３５ｍｍ未満であると生産効率が悪くなるおそれがあり、１．２ｍｍを超えるとコストの面から好ましくない。 In the above manufacturing method, the thermoplastic resin tape is obtained by cutting the thermoplastic resin sheet, so it is preferable that the thin thermoplastic resin sheet also have the same thickness as the thermoplastic resin tape. The thickness of the thick thermoplastic resin sheet is preferably 0.35 to 1.2 mm, more preferably 0.5 to 1.0 mm. If the thickness is less than 0.35 mm, production efficiency may deteriorate, and if it exceeds 1.2 mm, it is not preferable from the viewpoint of cost.
　本願は、２０２１年１０月１４日に出願された日本国特許出願第２０２１－１６９１３７号及び２０２１年１０月１９日に出願された日本国特許出願第２０２１－１７１１００号に基づく優先権の利益を主張するものである。２０２１年１０月１４日に出願された日本国特許出願第２０２１－１６９１３７号及び２０２１年１０月１９日に出願された日本国特許出願第２０２１－１７１１００号の明細書の全内容が、本願に参考のため援用される。 This application claims the benefit of priority based on Japanese Patent Application No. 2021-169137 filed on October 14, 2021 and Japanese Patent Application No. 2021-171100 filed on October 19, 2021 It is something to do. The entire contents of the specifications of Japanese Patent Application No. 2021-169137 filed on October 14, 2021 and Japanese Patent Application No. 2021-171100 filed on October 19, 2021 are referred to in this application. Incorporated for
　以下、本発明を実施例により説明するが、本発明はもとよりこれらの実施例に限定されるものではない。なお、各実施例および比較例において用いた評価方法は以下の通りである。 The present invention will be described below with reference to examples, but the present invention is not limited to these examples. The evaluation methods used in each example and comparative example are as follows.
＜無機繊維の体積含有率＞
　底面部、最外周に位置する筒状部の軸方向の先端部、及び最外周以外の筒状部の軸方向の先端部から、サンプルを切り出し、ＪＩＳ　Ｋ７２５０－１に準拠する直接灰化法にて計測された無機繊維の重量含有率を用いて、下式により各部位の無機繊維の体積含有率を算出した。なお、繊維密度及び樹脂密度の単位はｇ／ｃｍ3とする。 <Volume content of inorganic fibers>
Samples were cut from the bottom surface, the axial tip of the outermost cylindrical portion, and the axial tip of the cylindrical portion other than the outermost periphery, and subjected to direct ashing in accordance with JIS K7250-1. Using the weight content of the inorganic fibers measured in the section above, the volume content of the inorganic fibers at each site was calculated according to the following formula. The unit of fiber density and resin density is g/cm 3 .
Figure JPOXMLDOC01-appb-M000001
Figure JPOXMLDOC01-appb-M000001
　なお、底面部では、内部空間での底面部の中央近傍における無機繊維の含有率を測定しており、内部空間での底面部の中央近傍とは、図１の衝撃吸収部材では図４の斜線部分（測定部位４１）のことであり、図２や図３でも同様である。また、筒状部の軸方向の先端部とは、衝突エネルギーが最初に加わる側の先端部（底面部とは反対側の先端部）である。そして、最外周に位置する筒状部とは２つの内部空間の形成に共通して用いられている部分以外の筒状部（１つの内部空間のみの形成に用いられている部分）のことを指す。 In addition, in the bottom part, the content rate of inorganic fibers in the vicinity of the center of the bottom part in the internal space is measured, and the vicinity of the center of the bottom part in the internal space is the diagonal line in FIG. It is a part (measurement part 41), and the same applies to FIGS. 2 and 3 as well. Further, the tip in the axial direction of the cylindrical portion is the tip on the side to which collision energy is first applied (the tip on the side opposite to the bottom portion). The outermost cylindrical portion means a cylindrical portion other than the portion commonly used to form two internal spaces (the portion used to form only one internal space). Point.
＜落錘衝撃試験＞
　大型高速衝撃圧縮試験機（ＩＭ１０Ｔ－３０、ＩＭＡＴＥＫ社製）を用いて、作製した衝撃吸収部材の落錘衝撃試験を実施した。落錘衝撃試験は、重量１２１．２ｋｇの錐体を衝撃吸収部材より２．５ｍ高い位置から自由落下させることで、衝撃吸収部材の軸方向に衝撃圧縮荷重を加えることにより行った。衝撃荷重は、錐体側に取り付けたロードセルから計測した。計測された衝撃荷重と変位より、荷重－変位曲線を描いて積分することにより落錘衝撃試験時における衝撃吸収部材の吸収エネルギーを算出した。算出した吸収エネルギーを、落錘衝撃試験によって破壊した部分の重量で割ることにより、比吸収エネルギーを算出した。 <Falling weight impact test>
Using a large high-speed impact compression tester (IM10T-30, manufactured by IMATEK), a falling weight impact test was performed on the produced impact-absorbing member. The falling weight impact test was performed by free-falling a cone weighing 121.2 kg from a position 2.5 m higher than the impact absorbing member, thereby applying an impact compressive load in the axial direction of the impact absorbing member. The impact load was measured from a load cell attached to the cone side. From the measured impact load and displacement, a load-displacement curve was drawn and integrated to calculate the absorbed energy of the impact-absorbing member during the falling weight impact test. The specific absorbed energy was calculated by dividing the calculated absorbed energy by the weight of the portion destroyed by the falling weight impact test.
＜平均配向角度＞
　図１の衝撃吸収部材において、底面部における厚み方向に垂直な面に対する無機繊維の平均配向角度を測定した。具体的には、内部空間１４での底面部の中央近傍（図４の斜線部分（測定部位４１））の各無機繊維の配向角度を測定し、平均配向角度を算出した。 <Average Orientation Angle>
In the shock absorbing member of FIG. 1, the average orientation angle of the inorganic fibers with respect to the plane perpendicular to the thickness direction in the bottom portion was measured. Specifically, the orientation angle of each inorganic fiber was measured near the center of the bottom portion of the internal space 14 (hatched portion (measurement portion 41) in FIG. 4), and the average orientation angle was calculated.
（実施例１）
　無機繊維であるガラス繊維ロービング（日東紡社製、ＲＳ　１１０　ＱＬ－４８３、Ｅガラス、繊度：１１５０Ｔｅｘ、集束本数ｆ：２０００本、平均繊維径：１７μｍ）を直径２ｃｍのローラーを用いて開繊した。次に、プライムポリマー社製Ｊ１３７Ｍ（温度２３０℃、荷重２．１６ｋｇでのＭＦＲ：３０ｇ／１０分）及び旭テクノ工業社製ＰＰ－０４Ｍ（温度２３０℃、荷重２．１６ｋｇでのＭＦＲ：８８ｇ／１０分）のブレンドからなるマレイン酸変性ポリプロピレン樹脂（温度２３０℃、荷重２．１６ｋｇでのＭＦＲ：４５ｇ／１０分）を満たした槽を準備し、槽内の樹脂の温度を２４０℃とし、樹脂に０．６ＭＰａの圧力をかけた。続いて、開繊したガラス繊維ロービングを上記の槽に通し、ガラス繊維に樹脂を連続的に含浸させた。その後、樹脂を含浸させたガラス繊維を賦形ローラーで潰し冷却固化させて、熱可塑性樹脂シートを作製した。最後に、熱可塑性樹脂シートをカッティングし、無機繊維の含有率が４８体積％である幅３０ｍｍ、長さ３５ｍｍ、厚み０．１ｍｍの熱可塑性樹脂テープＡを作製した。 (Example 1)
A glass fiber roving (manufactured by Nittobo Co., Ltd., RS 110 QL-483, E glass, fineness: 1150 Tex, number of bundles f: 2000, average fiber diameter: 17 μm), which is an inorganic fiber, was opened using a roller with a diameter of 2 cm. . Next, Prime Polymer J137M (temperature 230 ° C., MFR at 2.16 kg load: 30 g / 10 minutes) and Asahi Techno Kogyo Co., Ltd. PP-04M (temperature 230 ° C., MFR at 2.16 kg load: 88 g / 10 minutes) blended maleic acid-modified polypropylene resin (temperature 230 ° C., MFR at a load of 2.16 kg: 45 g / 10 minutes) was prepared, the temperature of the resin in the tank was 240 ° C., and the resin was applied with a pressure of 0.6 MPa. Subsequently, the opened glass fiber roving was passed through the above tank to continuously impregnate the glass fiber with the resin. After that, the resin-impregnated glass fiber was crushed with a shaping roller and solidified by cooling to prepare a thermoplastic resin sheet. Finally, the thermoplastic resin sheet was cut to produce a thermoplastic resin tape A having a width of 30 mm, a length of 35 mm, and a thickness of 0.1 mm with an inorganic fiber content of 48% by volume.
　その後、金属製の耐熱離型容器内に熱可塑性樹脂テープＡをランダムに積層させた後、２４０℃に加熱された金型内で０．２ＭＰａの圧力をかけて５分間プレスし、シート内部のエアーを十分に抜いた後、１００℃に設定された金型内で２ＭＰａの圧力で２分間プレスすることにより、厚さが６ｍｍのスタンピング成形用シートを作製した。作製したスタンピング成形用シートを金型容積と同容積になるように切り出し、遠赤外線ヒーターでスタンピング成形用シートが２２０℃となるまで加熱後、１３０℃に設定された金型内に投入して圧力２５ＭＰａ、保圧時間２分にてスタンピング成形を行うことにより、図１に示す形状の衝撃吸収部材を得た。図１の衝撃吸収部材は底面部が縦８０ｍｍ、横１００ｍｍ、厚み４ｍｍであり、筒状部は高さ５２ｍｍであり、筒状部の先端部の厚さは２．２ｍｍであった。筒状部の高さは、底面部の最短辺の０．６５倍であった。実施例１の衝撃吸収部材の底面部における無機繊維の含有率は４７．５体積％であり、最外周に位置する筒状部における無機繊維の含有率は４７．９体積％であり、最外周以外の筒状部における無機繊維の含有率は４８．４体積％であった。実施例１における衝撃吸収部材の比吸収エネルギーは３６．６ｋＪ／ｋｇであり、平均配向角度は３．７°であった。 After that, the thermoplastic resin tape A was randomly laminated in a metal heat-resistant release container, and then pressed for 5 minutes with a pressure of 0.2 MPa in a mold heated to 240 ° C., and the inside of the sheet After the air was sufficiently removed, a stamping molding sheet having a thickness of 6 mm was produced by pressing for 2 minutes at a pressure of 2 MPa in a mold set at 100°C. The prepared sheet for stamping molding is cut out to have the same volume as the mold volume, heated with a far infrared heater until the sheet for stamping molding reaches 220 ° C., then put into the mold set at 130 ° C. and pressurized. A shock absorbing member having the shape shown in FIG. 1 was obtained by performing stamping molding at 25 MPa for a dwell time of 2 minutes. The shock absorbing member of FIG. 1 had a bottom portion of 80 mm long, 100 mm wide and 4 mm thick, a tubular portion 52 mm high, and a thickness of 2.2 mm at the tip of the tubular portion. The height of the tubular portion was 0.65 times the shortest side of the bottom portion. The content of inorganic fibers in the bottom portion of the shock absorbing member of Example 1 was 47.5% by volume, and the content of inorganic fibers in the tubular portion located on the outermost periphery was 47.9% by volume. The content of inorganic fibers in the cylindrical portion other than the above was 48.4% by volume. The specific absorbed energy of the impact absorbing member in Example 1 was 36.6 kJ/kg, and the average orientation angle was 3.7°.
（実施例２）
　実施例１と同様の方法でスタンピング成形用シートを作製した。作製したスタンピング成形用シートを切り出し、遠赤外線ヒーターでスタンピング成形用シートが２２０℃となるまで加熱後、１３０℃に設定された金型内に投入してスタンピング成形を行うことにより、図２に示す形状の衝撃吸収部材を得た。図２の衝撃吸収部材は底面部が縦６０ｍｍ、横６０ｍｍ、厚み４ｍｍであり、筒状部は高さ５２ｍｍであり、筒状部の先端部の厚さは２．２ｍｍであった。筒状部の高さは、底面部の最短辺の０．８７倍であった。実施例２の衝撃吸収部材の底面部における無機繊維の含有率は４７．８体積％であり、最外周に位置する筒状部における無機繊維の含有率は４８．２体積％であり、最外周以外の筒状部における無機繊維の含有率は４７．５体積％であった。実施例２における衝撃吸収部材の比吸収エネルギーは４０．５ｋＪ／ｋｇであった。 (Example 2)
A sheet for stamping molding was produced in the same manner as in Example 1. The prepared sheet for stamping molding was cut out, heated with a far-infrared heater until the sheet for stamping molding reached 220°C, and then put into a mold set at 130°C for stamping molding. A shaped impact absorbing member was obtained. The impact-absorbing member of FIG. 2 had a bottom portion of 60 mm long, 60 mm wide and 4 mm thick, a tubular portion 52 mm high, and a thickness of 2.2 mm at the tip of the tubular portion. The height of the tubular portion was 0.87 times the shortest side of the bottom portion. The content of inorganic fibers in the bottom portion of the shock absorbing member of Example 2 was 47.8% by volume, and the content of inorganic fibers in the tubular portion located on the outermost periphery was 48.2% by volume. The content of inorganic fibers in the cylindrical portion other than the above was 47.5% by volume. The specific absorbed energy of the shock absorbing member in Example 2 was 40.5 kJ/kg.
（実施例３）
　実施例１に記載のガラス繊維ロービングに代えて、炭素繊維ロービング（東レ社製Ｔ－７００、ポリアクリロニトリル、繊度：８００Ｔｅｘ、１２０００ｆ、平均繊維径：７μｍ）を用い、実施例１で用いられていた酸変性されたポリプロピレン樹脂に代えて、マレイン酸変性ポリプロピレン（東洋紡社製Ｇ２Ｈ、温度２３０℃、荷重２．１６ｋｇでのＭＦＲ：５０ｇ／１０分）を用いた以外は実施例１と同様の方法で、無機繊維の含有率が５０％である幅１５ｍｍ、長さ３５ｍｍ、厚み０．１ｍｍの熱可塑性樹脂テープＢを作製した。 (Example 3)
Instead of the glass fiber roving described in Example 1, carbon fiber roving (T-700 manufactured by Toray Industries, polyacrylonitrile, fineness: 800 Tex, 12000 f, average fiber diameter: 7 μm) was used in Example 1. In the same manner as in Example 1 except that maleic acid-modified polypropylene (G2H manufactured by Toyobo Co., Ltd., temperature 230 ° C., MFR at a load of 2.16 kg: 50 g / 10 minutes) was used instead of the acid-modified polypropylene resin. , a thermoplastic resin tape B having a width of 15 mm, a length of 35 mm, and a thickness of 0.1 mm and having an inorganic fiber content of 50% was produced.
　熱可塑性樹脂テープＡの代わりに熱可塑性樹脂テープＢを用いる以外は実施例１と同様の方法で図１に示す形状の衝撃吸収部材を得た。実施例３の衝撃吸収部材の底面部における無機繊維の含有率は４９．４体積％であり、最外周に位置する筒状部における無機繊維の含有率は５０．３体積％であり、最外周以外の筒状部における無機繊維の含有率は５０．１体積％であった。実施例３における衝撃吸収部材の比吸収エネルギーは４９．５ｋＪ／ｋｇであった。 A shock absorbing member having the shape shown in FIG. 1 was obtained in the same manner as in Example 1 except that the thermoplastic resin tape B was used instead of the thermoplastic resin tape A. The content of inorganic fibers in the bottom portion of the shock absorbing member of Example 3 was 49.4% by volume, and the content of inorganic fibers in the tubular portion located on the outermost periphery was 50.3% by volume. The content of the inorganic fibers in the tubular portion other than the above was 50.1% by volume. The specific absorbed energy of the impact absorbing member in Example 3 was 49.5 kJ/kg.
（実施例４）
　熱可塑性樹脂テープＡの代わりに熱可塑性樹脂テープＢを用いる以外は実施例２と同様の方法で図２に示す形状の衝撃吸収部材を得た。実施例４の衝撃吸収部材の底面部における無機繊維の含有率は５０．３体積％であり、最外周に位置する筒状部における無機繊維の含有率は４９．８体積％であり、最外周以外の筒状部における無機繊維の含有率は４９．９体積％であった。実施例４における衝撃吸収部材の比吸収エネルギーは５４．２ｋＪ／ｋｇであった。 (Example 4)
A shock absorbing member having the shape shown in FIG. The content of inorganic fibers in the bottom portion of the shock absorbing member of Example 4 was 50.3% by volume, and the content of inorganic fibers in the cylindrical portion located on the outermost periphery was 49.8% by volume. The content of inorganic fibers in the cylindrical portion other than the above was 49.9% by volume. The specific absorbed energy of the shock absorbing member in Example 4 was 54.2 kJ/kg.
（比較例１）
　ポリプロピレン及びガラス繊維を含む三菱ケミカルアドバンスドマテリアルズ社製Ｐ４０３８ＧＭＴ（ＧＭＴ、繊維長：１００ｍｍ、無機繊維の含有率：２０体積％、厚さ：３．８ｍｍ）を用いてスタンピング成形用シートを作製した以外は実施例１と同様の方法で図１に示す形状の衝撃吸収部材を得た。比較例１の衝撃吸収部材の底面部における無機繊維の含有率は２４．８体積％であり、最外周に位置する筒状部における無機繊維の含有率は１７．８体積％であり、最外周以外の筒状部における無機繊維の含有率は１６．２体積％であった。比較例１における衝撃吸収部材の比吸収エネルギーは２１．５ｋＪ／ｋｇであった。また、落錘衝撃試験における破壊時の挙動は、実施例１～４とは異なり、錐体が接触した箇所の近傍から粉々に砕けながら破壊が進行した。 (Comparative example 1)
Except for using Mitsubishi Chemical Advanced Materials P4038 GMT (GMT, fiber length: 100 mm, inorganic fiber content: 20% by volume, thickness: 3.8 mm) containing polypropylene and glass fiber to prepare a sheet for stamping molding. A shock absorbing member having the shape shown in FIG. 1 was obtained in the same manner as in Example 1. The content of inorganic fibers in the bottom portion of the shock absorbing member of Comparative Example 1 was 24.8% by volume, and the content of inorganic fibers in the cylindrical portion located on the outermost periphery was 17.8% by volume. The content of inorganic fibers in the cylindrical portion other than the above was 16.2% by volume. The specific absorbed energy of the shock absorbing member in Comparative Example 1 was 21.5 kJ/kg. In addition, unlike Examples 1 to 4, the behavior at the time of destruction in the falling weight impact test progressed while breaking into pieces from the vicinity of the contact point with the cone.
（比較例２）
　比較例１と同様の方法でスタンピング成形用シートを作製した以外は実施例１と同様の方法で図２に示す形状の衝撃吸収部材を得た。比較例２の衝撃吸収部材の底面部における無機繊維の含有率は２４．２体積％であり、最外周に位置する筒状部における無機繊維の含有率は１６．８体積％であり、最外周以外の筒状部における無機繊維の含有率は１８．５体積％であった。比較例２における衝撃吸収部材の比吸収エネルギーは２５．２ｋＪ／ｋｇであった。また、落錘衝撃試験における破壊時の挙動は、比較例１と同様に、錐体が接触した箇所の近傍から粉々に砕けながら破壊が進行した。 (Comparative example 2)
A shock absorbing member having the shape shown in FIG. The inorganic fiber content in the bottom portion of the shock absorbing member of Comparative Example 2 was 24.2% by volume, and the inorganic fiber content in the outermost cylindrical portion was 16.8% by volume. The content of inorganic fibers in the cylindrical portion other than the above was 18.5% by volume. The specific absorbed energy of the shock absorbing member in Comparative Example 2 was 25.2 kJ/kg. As for the behavior at the time of destruction in the falling weight impact test, as in Comparative Example 1, the destruction progressed while breaking into pieces from the vicinity of the contact point with the cone.
　本発明の衝撃吸収部材は、軽量化と高い衝突安全性とが両立できており、かつ、成形性に優れているため、乗用車の衝撃吸収装置に用いることができ、車体軽量化や省エネルギーの面から産業界に大きく寄与することが期待される。また、本発明の衝撃吸収部材は、乗用車の衝撃吸収装置に用いることができるのみならず、乗用車以外の車両や各種構造物にも用いることができる。 The shock absorbing member of the present invention can achieve both weight reduction and high collision safety, and is excellent in moldability, so that it can be used as a shock absorbing device for passenger cars, and can be used to reduce the weight of the vehicle body and save energy. It is expected that it will contribute greatly to the industrial world. In addition, the impact absorbing member of the present invention can be used not only for impact absorbing devices for passenger cars, but also for vehicles other than passenger cars and various structures.
１１、２１、３１　衝撃吸収部材
１２、２２、３２　底面部
１３、２３、３３　筒状部
１４、２４、２５、３４、３５　内部空間
４１　測定部位
  11, 21, 31 Impact absorbing members 12, 22, 32 Bottom surface parts 13, 23, 33 Cylindrical parts 14, 24, 25, 34, 35 Internal space 41 Measurement part

Claims (7)

  1. 　１つ以上の板状部材を有する衝撃吸収部材であって、
    　前記板状部材の少なくとも１つが、無機繊維を含む熱可塑性樹脂テープが積層されて形成されたものであり、
    　該無機繊維を含む板状部材において、前記無機繊維が板状部材の厚み方向に垂直な方向に配向していると共に、該垂直方向に沿った面内での配向がランダムであり、かつ前記無機繊維が前記板状部材中、３０～６０体積％であることを特徴とする衝撃吸収部材。     A shock absorbing member having one or more plate-shaped members,
    At least one of the plate-shaped members is formed by laminating thermoplastic resin tapes containing inorganic fibers,
    In the plate-shaped member containing the inorganic fibers, the inorganic fibers are oriented in a direction perpendicular to the thickness direction of the plate-shaped member, and the orientation in the plane along the perpendicular direction is random, and A shock absorbing member characterized in that fibers account for 30 to 60% by volume of said plate member.
  2. 　前記無機繊維が、ガラス繊維及び炭素繊維の少なくとも一種を含む請求項１に記載の衝撃吸収部材。 The impact absorbing member according to claim 1, wherein the inorganic fibers include at least one of glass fibers and carbon fibers.
  3. 　前記無機繊維の平均繊維長が１０～１５０ｍｍである請求項１又は２に記載の衝撃吸収部材。 The impact absorbing member according to claim 1 or 2, wherein the inorganic fibers have an average fiber length of 10 to 150 mm.
  4. 　温度２３０℃、荷重２．１６ｋｇで測定したときの前記熱可塑性樹脂テープに含まれる樹脂のメルトフローレートが１５～１００ｇ／１０分である請求項１又は２に記載の衝撃吸収部材。 The impact absorbing member according to claim 1 or 2, wherein the melt flow rate of the resin contained in the thermoplastic resin tape is 15 to 100 g/10 minutes when measured at a temperature of 230°C and a load of 2.16 kg.
  5. 　前記熱可塑性樹脂テープは、長さ１０ｍｍ～１００ｍｍ、幅５ｍｍ～５０ｍｍ、厚み０．０５ｍｍ～０．３ｍｍである請求項１又は２に記載の衝撃吸収部材。 The impact absorbing member according to claim 1 or 2, wherein the thermoplastic resin tape has a length of 10 mm to 100 mm, a width of 5 mm to 50 mm, and a thickness of 0.05 mm to 0.3 mm.
  6. 　筒状部と底面部とを有する衝撃吸収部材であって、
    　前記筒状部及び前記底面部は前記板状部材により構成されており、
    　前記底面部は、前記筒状部の一方の底面を塞いでおり、
    　前記筒状部における前記無機繊維の含有率と前記底面部における前記無機繊維の含有率との差が５体積％以下である請求項１又は２に記載の衝撃吸収部材。     A shock absorbing member having a cylindrical portion and a bottom portion,
    The cylindrical portion and the bottom portion are configured by the plate-like member,
    The bottom surface part closes one bottom surface of the tubular part,
    3. The impact absorbing member according to claim 1, wherein the difference between the inorganic fiber content in the cylindrical portion and the inorganic fiber content in the bottom portion is 5% by volume or less.
  7. 　前記底面部において、厚み方向に垂直な面に対する前記無機繊維の平均配向角度が０～２０°である請求項１又は２に記載の衝撃吸収部材。 The impact absorbing member according to claim 1 or 2, wherein the average orientation angle of the inorganic fibers with respect to the plane perpendicular to the thickness direction in the bottom portion is 0 to 20°.
PCT/JP2022/035617 2021-10-14 2022-09-26 Impact-absorbing member WO2023063057A1 (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP2021-169137 2021-10-14
JP2021169137 2021-10-14
JP2021171100 2021-10-19
JP2021-171100 2021-10-19

Publications (1)

Publication Number Publication Date
WO2023063057A1 true WO2023063057A1 (en) 2023-04-20

Family

ID=85988312

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2022/035617 WO2023063057A1 (en) 2021-10-14 2022-09-26 Impact-absorbing member

Country Status (1)

Country Link
WO (1) WO2023063057A1 (en)

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004142165A (en) * 2002-10-22 2004-05-20 Toyobo Co Ltd Compression molding material
JP2004223744A (en) * 2003-01-20 2004-08-12 Toyobo Co Ltd Impact absorbing fiber reinforced material and its manufacturing method
JP2004223743A (en) * 2003-01-20 2004-08-12 Toyobo Co Ltd Method for manufacturing impact absorbing body
JP2010150371A (en) * 2008-12-25 2010-07-08 Toyobo Co Ltd Carbon filament-reinforced polypropylene composite material
WO2013080974A1 (en) * 2011-11-28 2013-06-06 帝人株式会社 Shock absorption member
WO2015076283A1 (en) * 2013-11-20 2015-05-28 東洋紡株式会社 Fiber-reinforced thermoplastic resin sheet
JP2018159044A (en) * 2017-03-24 2018-10-11 三菱ケミカル株式会社 Resin composition for impact absorption members, and impact absorption member comprising the same

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004142165A (en) * 2002-10-22 2004-05-20 Toyobo Co Ltd Compression molding material
JP2004223744A (en) * 2003-01-20 2004-08-12 Toyobo Co Ltd Impact absorbing fiber reinforced material and its manufacturing method
JP2004223743A (en) * 2003-01-20 2004-08-12 Toyobo Co Ltd Method for manufacturing impact absorbing body
JP2010150371A (en) * 2008-12-25 2010-07-08 Toyobo Co Ltd Carbon filament-reinforced polypropylene composite material
WO2013080974A1 (en) * 2011-11-28 2013-06-06 帝人株式会社 Shock absorption member
WO2015076283A1 (en) * 2013-11-20 2015-05-28 東洋紡株式会社 Fiber-reinforced thermoplastic resin sheet
JP2018159044A (en) * 2017-03-24 2018-10-11 三菱ケミカル株式会社 Resin composition for impact absorption members, and impact absorption member comprising the same

Similar Documents

Publication Publication Date Title
EP2787241A1 (en) Shock absorption member
US9339988B2 (en) Joined body
CN103339023B (en) Vehicle skeleton members
KR101654951B1 (en) Structure for absorbing energy
ES2647862T3 (en) Composite materials reinforced with steel fiber
EP3275769B1 (en) Resin structure and vehicle components
US11584835B2 (en) Laminated substrate and method for manufacturing the same
WO2015119206A1 (en) Resin shock-absorbing member and vehicle component
EP3112719B1 (en) Resin impact-absorbing member
JP6808744B2 (en) How to make energy absorbing member and energy absorbing member
EP3135715A1 (en) Fiber-reinforced plastic joined body, method for producing fiber-reinforced plastic joined body, and fiber-reinforced molded article
US20140339036A1 (en) Shock Absorption Member
WO2023063057A1 (en) Impact-absorbing member
JP4491955B2 (en) Impact energy absorbing member made of fiber reinforced plastic
JP2007313973A (en) Vehicular panel
EP3636517B1 (en) Safety cabin for a residential or camper van with deformation elements
CN113573875A (en) Stitched multiaxial reinforcement
WO2023063058A1 (en) Impact-absorbing member
WO2024058007A1 (en) Method for manufacturing impact-absorbing member
WO2024058006A1 (en) Impact-absorbing member
US20200340544A1 (en) Component for absorbing impact force
Erkek et al. Hybridization effect on energy absorption capacity of composite crash boxes
JP6891516B2 (en) Energy absorbing member and its manufacturing method
JPH06307476A (en) Energy absorbing member
JP2024075795A (en) Shock absorbing materials

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 2023519708

Country of ref document: JP

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22880753

Country of ref document: EP

Kind code of ref document: A1