Showing papers on "Crash box published in 2006"

Front structure for car body

Abstract: A front structure for a car body that reduces time and cost to repair a car body after a collision by localizing damage in low-speed collisions to a crash box mounted in a space between a front bumper and a side member and making the car body deform always in a predetermined mode in the collisions A front structure for a car body may include a first connecting bracket supporting the left and right rear of a front bumper, a crash box joined to the rear of the first connecting bracket, a second connecting bracket joined to the rear of the crash box, and a front side member joined to the rear of the second connecting bracket The crash box includes an inner member and an outer member, which are curved and separated from each other, so as to extend in the longitudinal direction of the vehicle and have a closed cross section The inner member has a plurality of bead-shaped protrusions that are formed across the inner member and longitudinally spaced from each other

Bumper for a motor vehicle

Abstract: A bumper for a motor vehicle includes a cross member disposed transversely to side rails of a motor vehicle frame and having a U-shaped cross section with a wall and two legs extending from opposite ends of the wall. The cross member is supported via integral crash boxes against the side rails. Each crash box has a cross member proximal end which abuts against the wall of the cross member, and includes vertical legs and horizontal legs to define a casing-like configuration. The wall of the cross member is formed in an area of the cross member proximal end of the crash box with a depression which extends in a direction of the crash box, with the vertical legs of the crash box joined at the cross member proximal end to the wall of the cross member, and with the horizontal legs of the crash box spaced from the wall of the cross member by a distance.

A bumper beam mounting

Abstract: A bumper beam (11) is fastened in two crash boxes (12). The top part and bottom part of each crash box form fastening tabs (34,35) against the top and bottom of the bumper beam (11) and each tab is fastened to the bumper beam with more than one bolt (36,37,57 58). A first hole (55) fits a first bolt (57) whereas the other hole/holes (56) permit for the bumper beam to turn a limited amount around said first bolt. Each tab is fastened to the bumper beam with more than one bolt and nut fastener (36,37,57,58). A first hole (55) fits a first bolt (57) whereas the other hole/holes (56) permit for the bumper beam to turn a limited amount around said first bolt. If a crash box is compressed in an off-set crash, the other crash box remains intact.

A crash box and a method of fastening a bumper beam

Abstract: A bumper beam is fastened to a bumper beam (11) of a vehicle (13) with intermediate crash boxes (12). Each crash box comprises a left member (20) and a right member (21) formed of sheet metal, which are jointed together and have top portions (24,25) overlapping each other and bottom portions (22,23) overlapping each other to form double-sheet tabs (34,35). These tabs extend out over the top and bottom surfaces of the bumper beam and are fastened to these surfaces.

Energy absorption behaviour of austenitic and duplex stainless steels in a crash box geometry

Abstract: The improvement of the passive safety plays an important role in the development of new steels for automotive parts. At the same time aspects of weight reduction as well as the industrial feasibility have to be considered. Powered by these objectives, the development and application of new steel concepts for various purposes is promoted. For the present investigation especially weight reduction combined with an improvement of the passive safety are emphasised. As example one representative part of the body structure, the crash box, is considered. At the moment different steel grades (dual phase-, TRIP-and HSLA-steels) as well as fibre reinforced materials are applied. New materials for this special purpose have to exhibit outstanding formability, a high capacity to absorb energy during a possible crash and should be cost effective compared to already existing material concepts. During this project different grades of austenitic stainless steels with varying stability were compared to duplex stainless steels and a TRIP grade with regard to their possible application as crash-box material. The austenitic grades show excellent gradual formability according to their strength level. All of them exhibit an extraordinary strain hardening behaviour. The duplex grades show a lower formability but on a much higher yield level. Besides the determination of classical material data such as uni- and multi-axial flow curves, dynamic tensile tests and forming tests for the determination of forming limit curves were performed. The material data were used in the simulation of a drop tower test which is commonly used to evaluate the performance of different materials in car components. The results were then evaluated with regard to the absorbed energy, the folding behaviour and the resulting forces.

Influence of the strain path on crash properties of a crash-box structure by experimental and numerical approaches

Abstract: In order to reduce the gas emission without decreasing the passengers safety, the UHSS (Ultra High Strength Steel) steels are more and more used in the automotive industry. The very high mechanical characteristics of these steels allow to reduce the car weight thanks to the thickness reduction of the structure parts. The aim of this study is to analyse the plastic pre-strain effect (forming) on the crash properties of a crash-box structure. In order to achieve this goal, experimental rheological tests have been performed by combining quasi-static tensile tests followed by dynamic tensile test (8.10 -3 s -1 ≤ e ≤ 1000 s -1 ) for a TRIP steel produced by ARCELOR. The combination of these results allows to obtain a better understanding of the steel behaviour in dynamic loading under different strain paths. All these information are necessary for an efficient simulation of crash test by including a pertinent material response. A special attention is given to the influence of the previous forming process on the dynamical response of crash boxes.

Holder for the fastening of units, has two fastening arms for fastening of holder to crash box or bearing structure whereby clearance is provided between fastening arm and holder, into which crash box can deform

Abstract: The holder (1) has two fastening arms (8,9) for fastening of the holder which is a cast part, to the crash box or the bearing structure. A clearance (26) is provided between the fastening arm and the holder into which the crash box can deform. The holder has a v-shaped body (3) with a narrow end (4) and a broad end (5) from which the fastening arms originate. An independent claim is also included for the front region of the motor vehicle with the bearing structure.

Heavy goods vehicle has underrun protection beneath driver cab and containing crash boxes fixed on frame and assigned cable of traction unit as one unit

Abstract: The goods vehicle has a driver cab supported on the vehicle frame and an energy absorbing device (44) formed by crash boxes (42) fixed on the frame to provide underrun protection at the front end of the vehicle . Each crash box is assigned a cable (58) of the traction unit (56) which runs inside the hollow crash box. The cables are unloaded in the installation position and only become tensioned in the event of front impact.

Connection mechanism of impact box and transverse

Abstract: The invention relates to the fastening of a crash box (3, 3') to a cross member (2) in a bumper system (1). According to the invention, the crash box (3, 3') is fixed to the middle bar (20) of a cross member (2), which in relation to the street is higher or deeper than the longitudinal member (4) and, on one side, to a flange (24) and/or limb (22) of the cross member (2). By reinforcing the crash box (3) on one side, it is possible to significantly reduce the introduction of a bending moment into the longitudinal member(4). Preferably, the cross member (2) consists of a cap-shaped profile (2) and the crash box (3) consists of two half shells (30, 31).

Crash-box of automobile

Abstract: A crash box for a vehicle is provided to improve shock absorbing performance of the vehicle upon occurrence of vehicle collision without increasing the size of the crash box. A crash box for a vehicle, includes a crash box body(50), shock absorbing plates(60), and a crack protrusion(70). The crash box body is interposed between a bumper and a vehicle frame so as to absorb shock upon occurrence of vehicle crash. The crash box body is corrugated such that the crash box body is foldable. The shock absorbing plates are arranged in the crash box body. The crack protrusion is formed on a front frame(52) of the crash box body so that the shock absorbing plate is torn when the crash box body is folded.

차체용 알루미늄 크래쉬 박스의 충돌성능 평가

Abstract: This study deals with the crashworthiness of aluminum crash box for an auto-body with the various types of cross section. For the aluminum alloy, Al7003-T7, the dynamic tensile test was carried out to apply for crash analysis at the range of strain rate from 0.003/sec to 200/sec. The crash analysis was carried out for four cross sections, square and hexagonal with and without ribs. The analysis result shows that the absorbed internal energy and the reaction force of crash box with rib are higher than that of crash box without rib. This result is due to the interaction between member and rib and the collapse of rib with the buckling mode. And the energy absorption is also affected by the cross section shape. Hexagonal cross section shows higher energy absorption and reaction force than square cross section.

유한요소해석을 통한 알루미늄 크래쉬 박스의 형상 연구

Abstract: This study deals with the crashworthiness of aluminum crash box for an auto-body with the various types of cross section. For the aluminum alloy, the dynamic tensile test was carried out to apply for crash analysis at the range of strain rate from 0.003 to 200/sec. The crash analysis was carried out for three cross sections of rectangle, hexagon and octagon. The analysis result shows that the octagon cross section shape has higher crashworthiness than other cross section shapes. Effect of shape of rib in the cross section is important factor in crash analysis. Face-to-face rib shows higher specific energy absorption and lower peak load than edge-to-edge rib. The energy absorption and load are affected by the inclined angle of rigid wallin crash analysis. As inclined angle increases, peak load decreases and face-to-face rib shows high crashworthiness.