520results about "Elastic dampers" patented technology

An automotive body side structure includes: a side sill extending in a vehicle length direction; a battery pack disposed vehicle inside in a vehicle width direction relative to the side sill; and a collision energy absorptive part having a substantially U-shaped cross section, the substantially U-shaped cross section including: a bottom portion substantially parallel to a vehicle height direction; and a pair of side wall portions continuous from an upper end and a lower end of the bottom portion. The collision energy absorptive part is provided in a protruding shape toward vehicle outside in the vehicle width direction on an outer peripheral side in the vehicle width direction of the battery pack facing the side sill. The collision energy absorptive part is made of a steel sheet having a tensile strength of 270 MPa-class to 340 MPa-class and a plate thickness of 1.0 mm to 1.4 mm.

The invention relates to the technical field of mechanical metamaterials, in particular to a negative Poisson's ratio cell element with an embedded symmetrical broken subcell structure, which comprises a concave hexagonal main body, the concave hexagonal main body comprises two horizontal cell walls and inclined cell walls arranged at two ends of the two horizontal cell walls, and the central points of the two inclined cell walls are bent towards one side close to the central points of the horizontal cell walls; the number of the bent wall rods is two, and the two bent wall rods are symmetrically arranged in the inwards-concave hexagonal body. The inherent contradiction that the stretching performance must be sacrificed when the rigidity of a traditional concave honeycomb structure is improved is successfully solved, and the negative Poisson's ratio effect and the energy absorption capacity of the structure can be further improved while the structural rigidity is enhanced.

The invention discloses a self-adaptive impact-resistant protective metamaterial with a Poisson's ratio autonomous constraint function, which comprises a PMP honeycomb, the PMP honeycomb comprises a plurality of honeycomb unit cell structures, and each honeycomb unit cell structure comprises a hexagonal thin-wall structure I and a hexagonal thin-wall structure II internally connected in the hexagonal thin-wall structure I. The invention further discloses a preparation method of the self-adaptive impact-resistant protective metamaterial with the Poisson's ratio autonomous constraint function. Compared with an SHC honeycomb, the PMP honeycomb has the advantages that the dynamic Poisson ratio of the PMP honeycomb is relatively stable in the whole crushing process, and the initial fluctuation range is only 0.1. In addition, the average dynamic Poisson's ratio of the PMP honeycomb is relatively small, indicating that the PMP honeycomb is almost free of transverse deformation without additional assistance. After the PMP honeycomb is compressed to be densified, the transverse length of the PMP honeycomb is only increased by 3.5%. Wherein the PMP honeycomb has better self-constraint capability, so that the PMP honeycomb has a more stable energy absorption mode.

A steering column assembly includes a lower jacket. The steering column assembly also includes an upper jacket disposed within the lower jacket and being telescopingly adjustable relative to the lower jacket. The steering column assembly further includes a telescope drive assembly electrically moving a telescope drive nut axially to telescopingly adjust the upper jacket. The steering column assembly yet further includes an energy absorption strap directly coupled to the upper jacket and directly coupled to the telescope drive nut to transfer axial movement of the telescope drive nut to the upper jacket.

The invention relates to a concave angle asymmetric double-layer negative Poisson's ratio superstructure and application thereof. A concave angle asymmetric double-layer negative Poisson's ratio superstructure comprises bearing pressing plates symmetrically arranged at the upper end and the lower end and a plurality of unit cell elements arranged between the two pressing plates, and is characterized in that the unit cell elements are arranged at equal intervals in the transverse direction and the vertical direction respectively to form an m * n array, each unit cell unit comprises a double-layer concave corner body, transverse connecting rods on the two sides and a vertical connecting rod on the upper portion, the lower portion of each double-layer concave corner body is an outer flat plate cell wall, and the ends of the transverse connecting rods between every two transversely adjacent unit cell units are connected into a whole. And the end parts of the vertical connecting rods between the vertically adjacent unit cell elements are connected with the outer flat plate cell walls into a whole. The deformation mode of the superstructure is influenced by the impact speed, when the speed is increased, the deformation mode transits from overall deformation to local deformation, different local deformation zones are generated, the superstructure has different horizontal contraction processes at different impact speeds, the negative Poisson's ratio effect is reduced along with the increase of the speed, and the local deformation zones are reduced. The superstructure can be applied to anti-impact protection parts of automobiles, airplanes and unmanned aerial vehicles and anti-impact protection parts of wearable protection devices.

The invention provides a negative poisson ratio tension metamaterial structure and application thereof in impact resistance of an unmanned aerial vehicle. The negative Poisson's ratio stretch-draw metamaterial structure is composed of a plurality of two-dimensional D-bar stretch-draw integral structures. The two-dimensional D-bar stretch-draw integral structure is composed of a plurality of two-dimensional D-bar stretch-draw unit structures. The two-dimensional D-bar tensioning unit structure is composed of four same rod pieces, four rigid hinges and two same elastic ropes. Wherein every two of four rod pieces of the two-dimensional D-bar tensioning unit structure are connected through a rigid hinge to form a quadrilateral structure, and the four rigid hinges are diagonally connected and fixed through two elastic ropes; and two elastic ropes are adopted for fixing. Compared with other stretch-draw metamaterial structures, the stretch-draw metamaterial based on the two-dimensional D-bar has the advantages that the negative Poisson's ratio structure can be utilized to show better energy absorption characteristics, and when the unmanned aerial vehicle collides or falls off, impact force can be effectively dispersed, and damage to an aircraft body is reduced.

An energy absorption device for absorbing at least a portion of impact energy occurring in an impact of an impact body in a safety net construction includes at least one cable guiding unit forming at least one cable receiving region for receiving and / or guiding at least one cable, and further includes at least one energy absorption element, arranged in the cable receiving region and forming at least one friction surface for the guided cable, the energy absorption element being configured, if a force inducing movement of the cable across the friction surface is exerted on the cable, to selectively absorb at least a portion of energy the force created via substantial deformation and / or abrasion of the friction surface. A cable brake, particularly a block-and-tackle cable brake, includes an energy absorption element of the energy absorption device, which is arranged at the deflection element on a side facing toward the cable.

The invention discloses a chiral paper folding superstructure connecting pipe for vibration control, and relates to the technical field of structural mechanics and vibration reduction performance of cylindrical shell type connecting pipes. The invention aims to solve the problem that the existing chiral superstructure cannot meet the vibration reduction requirements under different frequencies. The structure comprises a plurality of superstructure unit cells, the superstructure unit cells are sequentially arranged from top to bottom in the axial direction, every two adjacent superstructure unit cells are connected through a set of unit cell connecting rods, the superstructure unit cells comprise a plurality of unit cells arranged in the circumferential direction, the upper ends of the unit cells are twisted anticlockwise, and the lower ends of the unit cells are twisted anticlockwise. And the upper end inner blade angle of each unit cell is connected with the lower end inner blade angle of the adjacent unit cell through a unit cell connecting rod, and the upper end outer blade angle of each unit cell is connected with the lower end outer blade angle of the adjacent unit cell through a unit cell connecting rod. The method is used for superstructure vibration reduction design.

The invention belongs to the technical field of vibration isolation, and particularly relates to a quasi-zero stiffness metamaterial sandwich structure, a vibration isolation device and a manufacturing method. The quasi-zero stiffness metamaterial sandwich structure is formed by periodically arranging unit cells in the horizontal direction, and each unit cell comprises an upper panel, a lower panel, a QZS resonator core body and a vertical supporting column; the QZS resonator core comprises a central mass block, QZS resonator units are arranged on the upper portion and the lower portion of the central mass block in a mirroring mode, each QZS resonator unit is composed of two quasi-zero-stiffness unit cells which are arranged in a crossed mode, and each quasi-zero-stiffness unit cell is composed of a negative-stiffness component comprising a horizontal curved beam and a positive-stiffness component comprising an oblique straight beam. According to the sandwich structure, the quasi-zero-stiffness resonator of a novel structure serves as a core body, wider application in the ultra-low frequency vibration reduction field can be achieved, the band gap is adjustable, and the problems that a traditional metal base material structure is high in band gap frequency and limited in application field can be solved.

An additively manufactured lattice includes a plurality of symmetrically oriented repeating unit cells. Each of the unit cells is comprised of a vertically oriented tubular structure having a top edge and bottom edge, said tubular structure defined by a circumferential side wall extending from said top edge to said bottom edge. The side wall has a lower portion, an intermediate portion, and an upper portion, with the lower portion terminating at the bottom edge, the upper portion terminating at the top edge, and the intermediate portion positioned between the lower portion and the upper portion. A plurality of spaced legs is included with each unit cell, with each leg formed as an outfolding of the side wall, each outfolding beginning at the side wall intermediate portion and extending progressively further outward through the side wall lower portion to the bottom edge.

The subject of the invention is an impact energy absorbing device, comprising a shock absorber (3) with a cylinder (3a) and piston rod (3b), a sleeve (1) to be cut and a machining tool (2) surrounding the sleeve (1) to be cut, for machining the surface of the sleeve (1) to be cut, characterized in that the sleeve (1) to be cut is a cylinder (3 a) of the shock absorber (3).

The present invention provides an embedded reinforced impact energy absorbing negative Poisson's ratio honeycomb lattice structure. The embedded reinforced impact energy absorbing negative Poisson's ratio honeycomb lattice structure comprises N embedded reinforced unit cells, each comprising a concave hexagonal unit cell structure and a sinusoidal structure embedded within the concave hexagonal unit cell structure. The embedded reinforced impact energy absorbing negative Poisson's ratio honeycomb lattice structure is formed by a periodic array of the embedded reinforced unit cells. The present invention effectively improves the compression stability, self-contact effect, specific energy absorption, and energy absorption efficiency of the negative Poisson's ratio honeycomb lattice structure, exhibiting excellent performance.

The application belongs to the technical field of deep-sea lander, and discloses a design method and system of a deep-sea landing buffer based on a filled TPMS structure, which comprises the following steps: S1, designing and preparing a filled TPMS structure; S2, performing a quasi-static compression test on the filled TPMS structure; S3, performing a dynamic impact performance test on the filled TPMS structure; S4, selecting a filled TPMS structure meeting preset requirements based on the results of the quasi-static compression test and the dynamic impact performance test, and designing a buffer system of a deep-sea lander; and S5, optimizing the buffer system of the deep-sea lander according to different application scenarios and equipment requirements. The application further explores the possibility of filling a magnetic fluid into a TPMS structure and applies the novel filled TPMS structure to a deep-sea landing buffer, thereby providing an efficient buffer solution for deep-sea exploration equipment.

To provide a plate-mounted steel damper that is installed in a building component and is easy to manufacture. [Solution] A plate-mounted steel plate damper (1000) includes a main structure (A1), a first cover plate (4), a second cover plate (6), two first side plates (5), and two second side plates (7). The main structure is made of H-shaped steel and has a first structural section (1), a second structural section (2), and a third structural section (3) located between the first and second structural sections. The first structural section includes a first web plate and two first flanges (12). The two first flanges are symmetrically and perpendicularly connected to both side edges of the first web plate. The second structural section includes a second web plate (21) and two second flanges (22). The two second flanges are symmetrically and perpendicularly connected to both side edges of the second web plate. The third structural section includes a third web plate (31) and two third flanges (32). The two third flanges are symmetrically and perpendicularly connected to both side edges of the third web plate.

The invention discloses a foamed aluminum multi-stage shock absorption and energy absorption device, and relates to the technical field of foamed aluminum shock absorption and energy absorption devices, the foamed aluminum multi-stage shock absorption and energy absorption device comprises an outer layer aluminum plate, a first foamed aluminum body, a base plate, a spring and an energy absorption unit, and the energy absorption unit comprises a moving block, a rubber body, a second foamed aluminum body and an energy absorption box; the outer-layer aluminum plate and the first foamed aluminum body form a rigid supporting and primary energy absorption layer, and the foamed aluminum porous structure is used for absorbing initial impact. The energy absorption units connected through the springs form secondary elastic buffering, progressive resistance is generated by pressing the circular-truncated-cone-shaped rubber body through the moving blocks, and stress is evenly dispersed in cooperation with the cellular board. A second foamed aluminum body and a rubber body combination are arranged in the energy absorption box, the second foamed aluminum body absorbs residual energy through plastic deformation, and the rubber body elastically deforms to achieve energy conversion. The shock absorption and energy absorption device has high energy absorption efficiency and structural stability, is suitable for a high-strength repeated impact environment, and remarkably improves the shock resistance and durability.

The invention relates to a damper (30, 40, 50) for a semiconductor technology system (1, 101), comprising at least one damping element (31, 41, 51) and two adjacent components (43.1, 43.2, 53.1, 53.2). The damping element (31, 41, 51) comprises a shape memory material with at least one main damping direction, and the damping element (31, 41, 51) is connected to the components (43.1, 43.2, 53.1, 53.2) such that tensile and compressive forces can be transmitted at least in the main damping direction. The damper (30, 40, 50) is characterized in that the damper (30, 40, 50) comprises an elastic element (42, 52.1, 52.2) for generating a mechanical restoring force in the direction of the main damping direction. The invention further relates to a damping arrangement (60) comprising a damper (30, 40, 50) according to one of the explained embodiments. The invention further relates to a system for semiconductor lithography (1, 101) comprising a damper (30, 40, 50) according to one of the explained embodiments and / or a damping arrangement (60) according to one of the explained embodiments.

The invention discloses a mechanical metamaterial cell element with a zero Poisson's ratio property, and belongs to the technical field of mechanical metamaterials. The upper top plate and the lower bottom plate are symmetrically arranged, the upper cleat nail set and the lower cleat nail set are arranged at the four corners of the inner side faces of the upper top plate and the lower bottom plate, the elastic body set is connected through the upper cleat nail set and the lower cleat nail set, and the flexible hinge component set is arranged at the midpoint position of four side lines of the upper top plate and the lower bottom plate. The flexible hinge component set keeps inward pre-bending through the pre-tension of the elastomer set, and when the cell element bears an axial load, the flexible hinge component set generates coordinated inward bending deformation, so that the cell element shrinks in the axial direction, the transverse size is kept stable, the axial zero Poisson's ratio characteristic is achieved, and meanwhile the energy absorption capacity is achieved. The cell element is based on elastic deformation, has self-recovery capability and long cycle life, adopts modular design, is convenient to assemble, disassemble and maintain, and is suitable for application scenes of aerospace buffer devices, biomedical implants, precise instrument supporting structures and the like.

A steering column assembly includes a lower jacket. The steering column assembly also includes an upper jacket disposed within the lower jacket and being telescopingly adjustable relative to the lower jacket. The steering column assembly further includes a telescope drive assembly electrically moving a telescope drive nut axially to telescopingly adjust the upper jacket. The steering column assembly yet further includes an energy absorption strap directly coupled to the upper jacket and directly coupled to the telescope drive nut to transfer axial movement of the telescope drive nut to the upper jacket.

The invention relates to an improved impact-resistant energy-absorbing structure of a trumpet-shell-imitating circular tube, and belongs to the technical field of impact-resistant protection, and a structural monomer or a structural modular array can be used for dynamic load protection. The structure of the circular tube is improved through a bionic method, on the premise that the mass of a traditional circular tube is not increased at all, the manufacturing cost is controllable by means of simple structural design, compared with the traditional circular tube, the energy absorption value under the unit mass is improved, and the problem of sharp initial peak crushing force existing in axial crushing of the traditional circular tube is thoroughly solved.

An aircraft including first and second elements spaced apart from one another and at least one device for absorbing energy by compression, positioned between the first and second elements, including at least one module for absorbing energy by compression and at least one attachment system removably connecting each module for absorbing energy by compression to at least one of the first and second elements, at least one module for absorbing energy by compression including several first conduits oriented in a compression direction and being independent of the first and second elements.

The negative poisson ratio energy absorption device comprises a honeycomb structure formed by a plurality of unit cell structure arrays, and each unit cell structure is formed by combining a plurality of plane energy absorption units around the same central axis in a radial shape in a crossed mode. Each plane energy absorption unit comprises an inwards-concave negative Poisson's ratio structure, two bionic treetop structures symmetrically arranged on the upper side and the lower side of the inwards-concave negative Poisson's ratio structure in the axial direction, and two connecting rods horizontally extending from the left side and the right side of the inwards-concave negative Poisson's ratio structure to the outer side. The bionic treetop structure comprises an arc-shaped top and a plurality of supporting rods distributed in a fan shape, one end of each supporting rod is connected to the arc-shaped top, and the other end of each supporting rod is connected to the concave negative Poisson's ratio structure; the device has the advantages that the device can adapt to multi-angle impact, and efficient and uniform energy absorption and light-weight protection are achieved through the negative Poisson's ratio effect.

The invention discloses a zero-Poisson-ratio composite material honeycomb core and a preparation method thereof, and belongs to the field of composite material forming. The honeycomb core comprises multiple layers of rib plates and multiple layers of stretching curved wall honeycombs, the rib plates are bonded between every two adjacent layers of stretching curved wall honeycombs and on the outer side of the stretching curved wall honeycomb on the outermost layer, and the multiple stretching curved wall honeycombs of each layer of stretching curved wall honeycombs are arranged in a matrix mode. A unit-cell concave hexagonal curved-wall honeycomb is formed between two adjacent stretching curved-wall honeycombs and rib plates, so that the zero Poisson ratio of the whole honeycomb structure is realized. The method comprises the following steps: designing the shapes of the prepreg and the demolding cloth; positioning the prepreg and the demolding cloth by using a positioning tool, and stacking the prepreg and the demolding cloth according to a specified sequence; for the thermosetting or thermoplastic fiber reinforced prepreg, a composite laminated plate is cured in a gradient manner by adopting a hot pressing process or a composite laminated plate is cured by adopting a mold pressing process; and finally, cutting, stretching, secondary curing, cooling and demolding cloth removal are carried out. The method is used for preparing the zero-Poisson-ratio composite material honeycomb core.

The invention discloses a vibration reduction and energy absorption honeycomb sandwich structure based on a symmetrical negative Poisson's ratio. The vibration reduction and energy absorption honeycomb sandwich structure comprises an upper panel, a lower panel and a honeycomb sandwich structure arranged between the upper panel and the lower panel. The honeycomb sandwich structure is formed by symmetrical arrow-shaped honeycomb cell elements which are symmetrically, transversely and longitudinally arranged regularly. According to the invention, the arrow-shaped cell element with the negative Poisson's ratio is inspired, the bottom of the arrow-shaped cell element is used as a symmetric axis, and the arrow-shaped honeycomb cell element is symmetric about the symmetric axis, so that the double-rhombus honeycomb cell element is obtained, and the negative Poisson's ratio characteristic of the honeycomb cell element is better reflected; and the resilience toughness, the vibration reduction performance and the impact resistance of the negative poisson ratio honeycomb sandwich structure can be effectively improved. Furthermore, the double-rhombus honeycomb sandwich structure can also solve the problems of large material loss and the like.

The invention relates to the technical field of bridge pile foundation construction, in particular to a bridge pile foundation construction vibration buffering device which comprises a support. The top end of the support is fixedly connected with a motor, the output end of the motor is fixedly connected with a lead screw, the lead screw is rotationally connected with the support, guide rods are arranged on the two sides of the lead screw and fixedly connected with the support, the outer side of the lead screw is in threaded connection with a lifting plate, and the two sides of the lifting plate are movably connected with the two guide rods in a sleeved mode respectively. Driving equipment is connected to the upper end of the lifting plate through a supporting assembly, a drill rod is fixedly connected to the bottom end of the driving equipment and penetrates through the supporting assembly and the lifting plate, and a clamping assembly is arranged on the outer side of the drill rod; the supporting assembly comprises a honeycomb plate, the honeycomb plate is composed of a plurality of honeycomb units, and the supporting assembly has the beneficial effects that by arranging multiple damping and buffering structures, it is prevented that driving equipment generates strong vibration in the running process, and consequently the driving equipment and a drill rod are greatly influenced, the stability of the drill rod in the drilling process is guaranteed, and therefore the construction quality is guaranteed.

The invention discloses a novel three-dimensional snowflake plate-shaped negative Poisson's ratio structure. A unit cell structure of the novel three-dimensional snowflake plate-shaped negative Poisson's ratio structure is composed of a double-folding bent plate, a trapezoidal bridge, a type I bearing column and a type II bearing column. The thickness of the double-folded bent plate is t, and the length of a middle folded corner is 2t; the included angle between the inner concave plate surface and the adjacent horizontal plane and the included angle between the trapezoidal bridge and the horizontal plane are a; the distance between the starting point of the longitudinal concave part and the I-shaped bearing column and the distance between the starting point of the transverse concave part and the center are both L; the I-shaped bearing column is a cuboid with a square section, and the side length of the bottom surface is d; and the width of the peripheral bent plate is l. The novel three-dimensional snowflake-plate-shaped negative poisson ratio unit cells are of a complete structure formed through transverse rotation and longitudinal array combination, the adjacent unit cells along the diagonal oblique lines share 1 / 2 bent plates, and the unit cell bearing columns and the bent plates adjacent in the vertical direction intersect. The novel three-dimensional snowflake-plate-shaped negative Poisson's ratio structure has an obvious negative Poisson's ratio effect and good energy absorption capacity in the vertical direction.

The invention discloses a self-adaptive multi-stage negative Poisson's ratio energy absorption device and a manufacturing method.The self-adaptive multi-stage negative Poisson's ratio energy absorption device comprises a shell and a negative Poisson's ratio honeycomb structure arranged in the shell, and the negative Poisson's ratio honeycomb structure is formed by a plurality of self-adaptive negative Poisson's ratio unit cell arrays; each self-adaptive negative Poisson's ratio unit cell comprises a negative Poisson's ratio framework, an upper supporting structure and a lower supporting structure, the upper supporting structure and the lower supporting structure are connected to the interior of the negative Poisson's ratio framework, a horizontal supporting platform is arranged in the middle of the negative Poisson's ratio framework, and a preset gap allowing the negative Poisson's ratio framework to shrink and deform is formed in the middle of the horizontal supporting platform of the negative Poisson's ratio framework; the upper supporting structure extends downwards from the joint with the negative Poisson's ratio framework and is provided with an upper supporting platform, and the lower supporting structure extends upwards from the joint with the negative Poisson's ratio framework and is provided with a lower supporting platform; the self-adaptive graded protection device has the advantages that elastic buffering reusability of low-speed collision and multi-stage efficient energy absorption of high-speed collision can be both considered, and self-adaptive graded protection is achieved.

The invention relates to the technical field of coal mine belt conveyors, and discloses a coal mine belt conveyor buffering and damping device which comprises a conveying frame, the inner wall of the conveying frame is in transmission connection with a conveying belt, a feeding box is movably installed on the top of the conveying frame, and a feeding pipe is fixedly connected to the bottom of the feeding box; and the bottom of the feeding pipe is fixedly connected with a connecting frame. The coal mine particle conveying device has the following advantages and effects that coal mine particles are conveyed to the end away from the feeding box along with conveying of the conveying belt to be fed, the coal mine particles press the conveying belt to make contact with the wear-resisting rubber blocks during discharging, the supporting and buffering effects are achieved, damping springs and damping telescopic rods stretch out and draw back to absorb energy generated by impact, and therefore vibration transmission of the conveying belt is reduced, and the conveying efficiency is improved. The conveying belt is made to be more stable when conveying coal mines, the conveying belt is prevented from being impacted and damaged in the feeding process, the service life of the conveyor is prolonged, adjustability is high, and the conveying speed of the conveying belt is changed and adjusted by adjusting the discharging amount.

This invention relates to the field of novel materials, specifically a novel metamaterial exhibiting both multi-stable state and negative Poisson's ratio properties. It comprises a concave hexagonal frame, two arc-shaped beams positioned on the upper and lower sides of the frame's inner cavity, and a vertical rod. The two arc-shaped beams are fixedly connected to the upper and lower ends of the vertical rod via their respective central portions. When the structure is subjected to a vertical compressive load, the frame's diagonal bracing rotates inward, contracting and compressing the ends of the arc-shaped beams, generating a significant negative Poisson's ratio effect. This process forces the arc-shaped beams to bend and deform towards the center, accompanied by energy dissipation. When the displacement reaches a critical threshold, the arc-shaped beams buckle and overturn, switching to a steady state. This invention, through specific geometric configurations and differentiated material layouts, achieves morphological self-repair after impact and reuse under low-intensity conditions. This metamaterial can be arranged as a two-dimensional periodic array as a unit cell.

To provide a part that reduces the weight of a shock absorbing device.SOLUTION: A part (10) includes a porous structure (15) including cellular pores (20) and formed at least in part by the periodic repetition of a basic pattern (50), each cellular pore being delimited by a wall (30), made of a metal or a polymer, having a parietal porosity greater than 5% and including parietal pores (31) with a mean size less than the mean size of the cellular pores.SELECTED DRAWING: Figure 1

This impact absorption structure for a vehicle body is provided with an energy absorption member (20) having a cap-shaped cross-sectional shape in the direction in which a collision load is input. The cap-shaped top plate portion (20A) is disposed so as to face the input direction. The joint parts (20D, 20E) of the flange parts (20C) and the top plate part (20A) with respect to the pair of vertical wall parts (20B) are formed in a curved shape. The first dimension (L1) of the curved shape on the flange section (20C) side is equal to or greater than a predetermined value and equal to or greater than the second dimension (L2) of the curved shape on the top plate section (20A) side with respect to the dimensions in the direction in which the flange sections (20C) of the curved shape extend.