Side crash test apparatus and side crash test condition determination method for center pillar of automobile
11946828 ยท 2024-04-02
Assignee
Inventors
Cpc classification
B62D25/04
PERFORMING OPERATIONS; TRANSPORTING
International classification
Abstract
A side crash test apparatus uses a crash test structure including a center pillar, a roof-rail simulated part, and a rocker simulated part, and includes: a striker; a roof rail support; and a rocker support. The rocker support includes a rocker-rotation braking mechanism configured to restrain translation of the rocker simulated part, and support the rocker simulated part to be rotatable about an axis thereof and allow braking of the rotation. The rocker-rotation braking mechanism includes a rocker-rotation support member configured to rotate about the axis together with the rocker simulated part, a rocker-rotation shaft support configured to support a rotation center of the rocker-rotation support member, a rocker-rotation braking plate extended by rotation of the rocker-rotation support member while braking the rotation when the striker crashes into the center pillar, and a rocker rotation braking plate fixed portion configured to fix another end side of the rocker-rotation braking plate.
Claims
1. A side crash test apparatus for a center pillar of an automobile, the side crash test apparatus conducting a side crash test of the center pillar using a crash test structure including: the center pillar of the automobile; a roof-rail simulated part connected to an upper end of the center pillar and simulating a roof rail of the automobile; and a rocker simulated part connected to a lower end of the center pillar and simulating a rocker of the automobile, the side crash test apparatus comprising: a striker configured to crash into a side of the center pillar; a roof rail support configured to support each of a front end and a rear end of the roof-rail simulated part; and a rocker support configured to support each of a front end and a rear end of the rocker simulated part, wherein the rocker support includes a rocker-rotation braking mechanism configured to restrain, when the striker crashes into the center pillar, translation of the rocker simulated part, and support the rocker simulated part to be rotatable about an axis thereof and allow braking of the rotation, and the rocker-rotation braking mechanism includes a rocker-rotation support member attached to an end face of the rocker simulated part, configured to rotate about the axis together with the rocker simulated part, and having an arc surface formed on at least a part of an outer face, a rocker-rotation shaft support configured to support a rotation center of the rocker-rotation support member to be rotatable while restraining translation thereof, a rocker-rotation braking plate for which one end side is attached to the outer face of the rocker-rotation support member and that is arranged along a tangential direction of the arc surface and, when the striker crashes into the center pillar, is extended by rotation of the rocker-rotation support member while braking the rotation and is wound around the arc surface, and a rocker-rotation braking plate fixed portion configured to fix another end side of the rocker-rotation braking plate.
2. The side crash test apparatus for the center pillar of the automobile according to claim 1, wherein the roof rail support includes a roof-rail rotation braking mechanism configured to restrain, when the striker crashes into the center pillar, translation of the roof-rail simulated part and to support the roof-rail simulated part to be rotatable about an axis thereof and allow braking of the rotation, and the roof-rail rotation braking mechanism includes a roof-rail rotation support member attached to an end face of the roof-rail simulated part, configured to rotate about the axis together with the roof-rail simulated part, and having an arc surface formed on at least a part of an outer face, a roof-rail rotation shaft support configured to support a rotation center of the roof-rail rotation support member to be rotatable while restraining translation thereof, a roof-rail rotation braking plate for which one end side is attached to the outer face of the roof-rail rotation support member and that is arranged along a tangential direction of the arc surface and, when the striker crashes into the center pillar, is extended by rotation of the roof-rail rotation support member while braking the rotation and is wound around the arc surface, and a roof-rail rotation braking plate fixed portion configured to fix another end side of the roof-rail rotation braking plate.
3. The side crash test apparatus for the center pillar of the automobile according to claim 2, wherein at least one of material property, shape, and dimensions of the roof-rail rotation braking plate in the roof-rail rotation braking mechanism is made different on a front end side and a rear end side of the roof-rail simulated part.
4. The side crash test apparatus for a center pillar of an automobile according to claim 1, wherein at least one of material property, shape, and dimensions of the rocker-rotation braking plate in the rocker-rotation braking mechanism is made different on a front end side and a rear end side of the rocker simulated part.
5. A side crash test condition determination method for the center pillar of the automobile that determines material property, shape, and dimensions of the rocker-rotation braking plate used in the side crash test apparatus for the center pillar of the automobile according to claim 1 as test conditions, the side crash test condition determination method comprising: a vehicle-model creation step of creating a vehicle model that modeled the automobile; a vehicle-model side crash analysis step of, by performing side crash analysis in which a striking body crashes into the side of the center pillar from a side of the vehicle model, acquiring a rotation angle around the axis of the rocker of the automobile in the vehicle model by the side crash analysis; a side-crash test model creation step of creating a side-crash test model that modeled the crash test structure and the side crash test apparatus; a rotation-braking plate setting step of setting material property, shape, and dimensions of the rocker-rotation braking plate in the side-crash test model; a side-crash test model analysis step of, by performing side crash analysis in which a striker crashes into the center pillar of the side-crash test model, acquiring a rotation angle of the rocker simulated part; a rotation-angle comparison step of comparing the rotation angle of the rocker acquired at the vehicle-model side crash analysis step with the rotation angle of the rocker simulated part acquired at the side-crash test model analysis step; a repetition step of repeatedly performing the rotation-braking plate setting step, the side-crash test model analysis step, and the rotation-angle comparison step, until the rotation angles compared at the rotation-angle comparison step are in a predetermined range by changing the material property, shape, and dimensions of the rocker-rotation braking plate; and a test-condition determination step of determining, as test conditions, the material property, shape, and dimensions of the rocker-rotation braking plate in a case where the compared rotation angle of the rocker simulated part and the rotation angle of the rocker are in the predetermined range at the repetition step.
Description
BRIEF DESCRIPTION OF DRAWINGS
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DESCRIPTION OF EMBODIMENTS
(14) In recent years, due to the strengthening of collision safety performance required for automobiles, high-strength steel sheets have been applied to the center pillars, and the strength has been drastically improved. At the same time, the high-strength steel sheets have also been applied to the roof rails and the rockers that support the center pillars, drastically improving the strength. Therefore, the deformation of the center pillar in the side crash test of the real vehicle for which the high-strength steel sheet is used for the center pillar is in a state where, along with the suppression of deformation of the roof rail and the rocker, the fracture in the lower portion near the portion connected to the rocker is unlikely to arise.
(15) Meanwhile, as in the foregoing, in the side crash test of the center pillar 101 using the crash test structure 100 as illustrated in
(16) Thus, the inventors enthusiastically examined measures capable of successfully reproducing the fracture phenomenon of the center pillar in the side crash with the real vehicle, in the side crash test of the center pillar 101 using the crash test structure 100 as illustrated in
(17) Prior to explaining embodiments of the present invention, a crash test structure having a center pillar to be the target of the side crash test in the present invention will be described in the following. In the present specification and the drawings, the center pillar is described to be arranged in a standing state so that the posture of the center pillar in the side crash test is the same as the posture of the center pillar in the real vehicle of an automobile, but the posture and arrangement of the center pillar are not limited thereto in the present invention. Thus, the terms describing the positions and directions such as upper end, lower end, side, front end, and rear end in the present invention represent relative positions and directions (vehicle vertical direction, vehicle width direction, and vehicle longitudinal direction) in reference to the posture and arrangement of the center pillar in the real vehicle of the automobile, not representing the absolute positions and directions in reference to the posture and arrangement of the center pillar in the side crash test. Furthermore, in the present specification and the drawings, elements having a substantially identical function and configuration are denoted by identical reference signs.
Crash Test Structure
(18) The crash test structure 100 has, as illustrated in
(19) The roof-rail simulated part 103 simulates the roof rail of the real vehicle of an automobile and is obtained by cutting the roof rail at a plane perpendicular to the vehicle longitudinal direction in front and rear of the portion connected to the upper end of the center pillar 101. At the front end and the rear end of the roof-rail simulated part 103, fixing plates 107 are joined, as members for attaching it to a side crash test apparatus for a center pillar of an automobile which will be described later. The roof-rail simulated part 103 may be a cutout of the roof rail of the real vehicle.
(20) The rocker simulated part 105 simulates the rocker of the real vehicle of an automobile and is obtained by cutting the rocker at a plane perpendicular to the vehicle longitudinal direction in front and rear of the portion connected to the lower end of the center pillar 101. At the front end and the rear end of the rocker simulated part 105, discs 109 are joined, as members for attaching it to the side crash test apparatus for a center pillar of an automobile which will be described later. The rocker simulated part 105 may be a cutout of the rocker of the real vehicle.
First Embodiment
(21) A side crash test apparatus 1 for a center pillar of an automobile according to a first embodiment of the present invention (hereinafter simply referred to as side crash test apparatus 1) conducts a side crash test of the center pillar 101 using the crash test structure 100 as illustrated in
Striker
(22) The striker 3 is made to crash into the side of the center pillar 101 in the horizontal direction from the side of the crash test structure 100 (corresponding to the outside of the vehicle in the vehicle width direction) and has a lower punch 3a that simulates the bumper of the other vehicle that crashes into the side of the center pillar from the side of the real vehicle and an upper punch 3b that simulates the vehicle body of the other vehicle.
Roof Rail Support
(23) The roof rail support 5 supports each of the front end and the rear end of the roof-rail simulated part 103. In the side crash test apparatus 1 according to the first embodiment, the roof rail support 5 supports the roof-rail simulated part 103 via the fixing plates 107 (see
(24) In addition, on the roof rail support 5, a load cell 11 (see
Rocker Support
(25) The rocker support 7 supports each of the front end and the rear end of the rocker simulated part 105 and has the rocker-rotation braking mechanism 9 that, when the striker 3 is made to crash into the side of the center pillar 101, restrains the translation of the rocker simulated part 105 and supports it to be rotatable about the axis thereof and allow braking of the rotation.
(26) On the rocker support 7, a load cell 15 (see
Rocker-Rotation Braking Mechanism
(27) The rocker-rotation braking mechanism 9 has a rocker-rotation support member 19, a rocker rotation shaft 21 (see
Rocker-Rotation Support Member
(28) The rocker-rotation support member 19 is a member that is attached to each end face of the front end and the rear end of the rocker simulated part 105 and rotates about the axis thereof together with the rocker simulated part 105 and on which an arc surface 19a (
(29) In the side crash test using the real vehicle of an automobile, some are made to crash at speeds from 30 km/h and, further, exceeding 50 km/h. In crashing at such a high speed, the rotational movement such as torsion of the roof rail and the rocker also becomes high speed.
(30) The rocker-rotation support member 19 and the disc 109 rotate together with the rocker simulated part 105, but if the moment of inertia of the rocker-rotation support member 19 and the disc 109 around such a rotation axis is excessively large, the rotation is delayed as a large braking force is applied when the rocker simulated part 105 tries to rotate in the crash test at high speed, and when stopping the rotation, the deceleration is delayed and the rotational angle is further increased, so that a significant deviation from the rotational behavior such as torsion of the rocker in the side crash test of the real vehicle may arise.
(31) Therefore, as compared with the moment of inertia of the rocker from the rear end of the lower portion of the front pillar to the front end of the lower portion of the rear pillar in the real vehicle, with the longitudinal direction of the vehicle as an axis, the dimensions and materials of the rocker-rotation support member 19 and the disc 109 are selected so that the total moment of inertia of the rocker-rotation support member 19 and the disc 109 in the side crash test apparatus 1 is 10 times or less, more preferably 5 times or less, thereby allowing the destructive phenomenon of the center pillar in the side crash test of the real vehicle to be reproduced successfully.
Rocker Rotation Shaft
(32) The rocker rotation shaft 21 is obtained by, as illustrated in
Rocker-Rotation Shaft Support
(33) The rocker-rotation shaft support 23 rotatably supports the rocker rotation shaft 21, restraining the translation thereof.
Rocker-Rotation Braking Plate
(34) In the rocker-rotation braking plate 25, one end side is attached to the outer face of the rocker-rotation support member 19 and is arranged along the tangential direction of the arc in the arc surface 19a (
Rocker-Rotation Braking Plate Fixed Portion
(35) The rocker-rotation braking plate fixed portion 27 fixes the end 25b (
(36) Next, the action and effect of the side crash test apparatus according to the present invention will be described with reference to
(37) As illustrated in
(38) At this time, as the rocker-rotation braking plate 25 is attached to the outer face of the rocker-rotation support member 19, a load in the tensile direction acts on the rocker-rotation braking plate 25 due to the rotation of the rocker-rotation support member 19. Due to this load in the tensile direction, the rocker-rotation braking plate 25 is extended and the braking is applied to the rotation of the rocker-rotation support member 19. Then, the extended rocker-rotation braking plate 25 is wound around the arc surface 19a along with the rotation of the rocker-rotation support member 19.
(39) As just described, by supporting the front end and the rear end of the rocker simulated part 105 by the rocker supports 7 having the rocker-rotation braking mechanism 9, with a simple mechanism, it is possible to restrain the translation of the rocker simulated part 105, allow it to be rotatable about the axis thereof, and apply the braking to the rotation, so that the destructive phenomenon of the center pillar that arises in the side crash test using the real vehicle can be reproduced.
(40) Moreover, in the side crash test apparatus according to the present invention, by changing the material property, shape, and dimensions of the rocker-rotation braking plate 25 as appropriate, the braking applied to the rotation of the rocker simulated part 105 can be adjusted.
(41) As for the material of the rocker-rotation braking plate 25, it only needs to have a tensile strength that allows it to extend without fracture when a load in the tensile direction acted on the rocker-rotation braking plate 25 due to the rotation of the rocker simulated part 105, and mild steel and oxygen-free copper can be exemplified.
(42) As for the shape of the rocker-rotation braking plate 25, as in the foregoing, in addition to the dumbbell shape in planar view having the parallel portion 25a between the ends 25b and 25b as illustrated in
(43) From this point of view, in the dumbbell-shaped rocker-rotation braking plate 25, when the striker 3 (
(44) As for the dimensions of the rocker-rotation braking plate 25, it only needs to set the sheet thickness and sheet width so as to avoid fracture against the load in the tensile direction due to the rotation of the rocker-rotation support member 19 and to set the length to extend without fracture.
(45) As just described, as the parameters of the rocker-rotation braking plate 25, by setting the material property, shape, and dimensions as appropriate, the reproducibility of the destructive phenomenon of the center pillar that arises in the real vehicle can be improved. As a result, by small-scaled crash tests without using the real vehicle, the structure and material of the center pillar can be examined, and the number of structural reviews with real vehicles is reduced, so that the development of the body frame structure can be made efficient.
(46) The rocker-rotation braking plates 25 do not need to have the same material properties, shapes, and dimensions on the front end side and the rear end side of the rocker simulated part 105. That is, according to the difference in the rotation about the axes of the front end and the rear end of the rocker in the side crash test of the target vehicle, at least one of the material property, shape, and dimensions of the rocker-rotation braking plates 25 may be made different on the front end side and the rear end side of the rocker simulated part 105.
(47) In the description according to the above-described first embodiment, the rocker support 7 and the rocker-rotation braking mechanism 9 have been made up individually, but more preferably, it is better configured that, as illustrated in
(48) The rocker support 41 supports each of the front end and the rear end of the rocker simulated part 105 and has the rocker-rotation braking mechanism 43 that, when the striker 3 is made to crash into the side of the center pillar 101, restrains the translation of the rocker simulated part 105 and supports it to be rotatable about the axis thereof and allow braking of the rotation.
(49) The rocker-rotation braking mechanism 43 has a rocker-rotation support member 45, a rocker-rotation shaft support 47, the rocker-rotation braking plate 25, and the rocker-rotation braking plate fixed portion 27.
(50) The rocker-rotation support member 45 is, as with the above-described rocker-rotation support member 19 (see
(51) The rocker-rotation shaft support 47 supports, in place of the above-described rocker rotation shaft 21 (see
(52) In the other configuration of the first embodiment as illustrated in
(53) In this way, the rocker support load acting in the vehicle width direction and the rocker rotation braking load acting in the vehicle height direction act on the point matched as viewed from the crash direction of the striker 3, so that the rotation and torsion other than about the rotation axis of the rocker simulated part 105 can be suppressed and the rotation of the rocker simulated part 105 can be made closer to the movement of the rocker in the crash test of the real vehicle.
(54) In the side crash test apparatus 1 according to the above-described first embodiment, while the rocker support 7 supporting the rocker simulated part 105 was supported so as to restrain the translation of the front end and the rear end of the rocker simulated part 105 and to be rotatable about the axis thereof, the roof rail support 5 supporting the roof-rail simulated part 103 was supported so as to restrain both the translation and the rotation of the front end and the rear end of the roof-rail simulated part 103.
(55) However, in the side crash test apparatus according to the present invention, as schematically illustrated in
(56) The roof-rail rotation braking mechanism 31 has, as with the foregoing rocker-rotation braking mechanism 9, a roof-rail rotation support member 33, a roof-rail rotation shaft (not illustrated), a roof-rail rotation shaft support (not illustrated), a roof-rail rotation braking plate 35, and a roof-rail rotation braking plate fixed portion 37.
(57) The roof-rail rotation support member 33 is a member that is attached to each end face of the front end and the rear end of the roof-rail simulated part 103, rotates about the axis together with the roof-rail simulated part 103, and on at least a part of the outer face, an arc surface 33a (
(58) The roof-rail rotation shaft protrudes outward in the rotation axis direction from the rotation center of the roof-rail rotation support member 33. The roof-rail rotation shaft support rotatably supports the roof-rail rotation shaft, restraining the translation thereof.
(59) In the roof-rail rotation braking plate 35, one end side is attached to the outer face of the roof-rail rotation support member 33 and is arranged along the tangential direction of the arc in the arc surface 33a and, by extending due to the rotation of the roof-rail simulated part 103 when the striker 3 is made to crash into the side of the center pillar 101, applies braking to the rotation and is wound around the arc surface 33a. Examples of the shape of the roof-rail rotation braking plate 35 include a dumbbell shape (see
(60) As just described, in addition to supporting the front end and the rear end of the rocker simulated part 105 by the rocker supports 7 having the rocker-rotation braking mechanism 9, by supporting the front end and the rear end of the roof-rail simulated part 103 by the roof rail supports 5 having the roof-rail rotation braking mechanism 31, it is possible, when the striker 3 crashed into the center pillar 101 of the crash test structure 100, to restrain the translation of the roof-rail simulated part 103 and to allow it to be rotatable about the axis thereof and apply braking to the rotation, so that the reproducibility of the destructive phenomenon of the center pillar that arises in the side crash test using the real vehicle can be further improved.
(61) In the side crash test apparatus according to the present invention, as with the rocker-rotation braking plate 25, by changing the material property, shape, and dimensions of the roof-rail rotation braking plate 35 as appropriate, the braking applied to the rotation of the roof-rail simulated part 103 can be adjusted.
(62) Moreover, the roof-rail rotation braking plates 35 do not need to have the same material properties, shapes, and dimensions on the front end side and the rear end side of the roof-rail simulated part 103. That is, according to the difference in the rotation about the axes of the front end and rear end of the roof rail in the side crash test of the target vehicle, at least one of the material properties, shapes, and dimensions of the roof-rail rotation braking plates 35 may be made different on the front end side and the rear end side of the roof-rail simulated part 103.
(63) In the side crash test apparatus according to the present invention, as illustrated in
(64) In particular, in the present invention, the rocker-rotation braking plate 25 in the rocker-rotation braking mechanism 9 of the rocker support 7 is arranged in the tangential direction of the arc surface 19a of the rocker-rotation support member 19. Moreover, in the roof rail support 5 having the roof-rail rotation braking mechanism 31, the roof-rail rotation braking plate 35 is arranged in the tangential direction of the arc surface 19a of the rocker-rotation support member 19 and the direction orthogonal to the crash direction of the striker 3. Thus, eliminating the influence of the braking of the rotation of the rocker-rotation support member 19 by the rocker-rotation braking plate 25 and the braking of the rotation of the roof-rail rotation support member 33 by the roof-rail rotation braking plate 35, the load at the time of side crash of the center pillar 101 can be acquired. Then, based on the acquired load, the information useful for examining and selecting the structure and material of the center pillar can be obtained.
(65) The side crash test apparatus according to the present invention is preferable to be configured (not illustrated) so that, even if it supports the roof-rail simulated part 103 as illustrated in
(66) In the above description, the disc 109 has been joined to each of the front end and the rear end of the rocker simulated part 105 and the rocker-rotation support member 19 has been attached to the disc 109, but in the present invention, the rocker-rotation support member 19 may be directly joined to each of the front end and the rear end of the rocker simulated part 105 without the disc 109 interposed therebetween.
(67) Similarly, even in a case that the roof rail support 5 has the roof-rail rotation braking mechanism 31 as illustrated in
Second Embodiment
(68) A side crash test condition determining method for a center pillar of an automobile according to a second embodiment of the present invention is a method of determining the material property, shape, and dimensions of the rocker-rotation braking plate 25 as test conditions of side crash test, when conducting the side crash test of the center pillar 101 by the side crash test apparatus 1 according to the above-described first embodiment, and includes, as illustrated in
Vehicle-Model Creation Step
(69) The vehicle-model creation step S1 is a step to create a vehicle model that modeled the real vehicle of an automobile. In the creation of the vehicle model, it only needs to mesh the geometry of the real vehicle of an automobile into three-dimensional elements and/or two-dimensional elements.
Vehicle-Model Side Crash Analysis Step S3
(70) The vehicle-model side crash analysis step S3 is a step to perform side crash analysis in which, from the side of the vehicle model created at the vehicle-model creation step S1, a model of a striking body such as another vehicle is made to crash into the side of the center pillar of the vehicle model, and acquire a rotation angle around the axis of the rocker in the vehicle model by the side crash analysis. At the vehicle-model side crash analysis step S3, the side crash analysis only needs to be performed by the finite element method (FEM) analysis.
Side-crash Test Model Creation Step S5
(71) The side-crash test model creation step S5 is a step to create a side-crash test model 110 (see
(72) The side-crash test model 110 is created by meshing the crash test structure 100 and the side crash test apparatus 1 into three-dimensional elements and/or two-dimensional elements. The modeling of the side crash test apparatus 1 does not need to model all constituent elements of the side crash test apparatus 1 and it only needs to model at least the striker 3, the roof rail support 5, and the rocker support 7 that has the rocker-rotation braking mechanism 9.
(73) In the creation of the side-crash test model 110, at the side-crash test model analysis step S9 which will be described later, if the translation of the roof-rail simulated part 103 and the rocker simulated part 105 are restrained, the rotation about the axes thereof, and the braking thereof are possible, each constituent element of the side crash test apparatus 1 may be modeled in a simplified shape as illustrated in
Rotation-Braking Plate Setting Step S7
(74) The rotation-braking plate setting step S7 is a step to set the material property, shape, and dimensions of the rocker-rotation braking plate 25 in the side-crash test model 110 created at the side-crash test model creation step S5. Examples of the material property of the rocker-rotation braking plate 25 include material, material strength, and the like, examples of the shape include a rectangle shape and a dumbbell shape (see
Side-Crash Test Model Analysis Step S9
(75) The side-crash test model analysis step S9 is a step to perform side crash analysis in which, from the side of the side-crash test model 110, the striker 3 is made to crash into the side of the center pillar 101, and acquire the rotation angle of the rocker simulated part 105 of the side-crash test model 110. At the side-crash test model analysis step S9, the side crash analysis of the side-crash test model 110 only needs to be performed by the FEM analysis.
Rotation-Angle Comparison Step S11
(76) The rotation-angle comparison step S11 is a step to compare the rotation angle of the rocker acquired at the vehicle-model side crash analysis step S3 with the rotation angle of the rocker simulated part 105 acquired at the side-crash test model analysis step S9.
Repetition Step S13
(77) The repetition step S13 is a step to repeatedly perform the rotation-braking plate setting step S7, the side-crash test model analysis step S9, and the rotation-angle comparison step S11, until the rotation angles compared at the rotation-angle comparison step S11 are in a predetermined range by changing the material property, shape, and dimensions of the rocker-rotation braking plate 25. The predetermined range is a case where the rotation angle is within ?0.5?, for example.
Test-Condition Determination Step S15
(78) The test-condition determination step S15 is a step to determine, as the test conditions of the side crash test of the center pillar 101 using the side crash test apparatus 1, the material property, shape, and dimensions of the rocker-rotation braking plate 25 at the time the rotation angle of the rocker simulated part 105 of the side-crash test model 110 is in a predetermined range with respect to the rotation angle of the rocker of the vehicle model.
(79) According to the side crash test condition determination method for a center pillar of an automobile in the second embodiment, the material property, shape, and dimensions as the parameters of the rocker-rotation braking plate 25 used in the side crash test apparatus 1 in the foregoing first embodiment have been determined as the test conditions of the side crash test using the side crash test apparatus 1, so that it is possible to successfully reproduce the destructive phenomenon of the center pillar that arises in the side crash test of the real vehicle, with a simpler mechanism and simpler condition adjustment. As a result, by small-scaled side crash tests without using the real vehicle, the structure and material of the center pillar can be examined and selected and the number of structural reviews of real vehicles is reduced, so that the development of the body frame structure can be made efficient.
(80) The rocker-rotation braking plate 25 for which the parameters are set at the rotation-braking plate setting step may be configured by stacking two or more metal sheets having different material strengths, or by further joining the stacked metal sheets. Moreover, the metal sheets to be stacked are not limited to those of the same material (for example, copper sheets, steel sheets) and may be of different materials (for example, copper sheet and steel sheet), and the combination of the material, shape, and dimensions of the metal sheets to be stacked may be selected as appropriate.
(81) In the above description, the parameters of the rocker-rotation braking plate 25 have been determined as the side crash test conditions but, assuming that the roof-rail simulated part 103 is supported by the roof rail support 5 having the roof-rail rotation braking mechanism 31 as illustrated in
(82) Specifically, first, at the vehicle-model side crash analysis step S3, the rotation angle around the axis of the roof rail in the vehicle model is acquired. Then, by creating the side-crash test model 110 for which the front end and the rear end of the roof-rail simulated part 103 are supported by the roof rail supports 5 having the roof-rail rotation braking mechanism 31 as illustrated in
(83) Then, by comparing the rotation angle of the roof rail acquired at the vehicle-model side crash analysis step S3 with the rotation angle of the roof-rail simulated part 103 acquired at the side-crash test model analysis step S9, and until the compared rotation angles are in a predetermined range, while changing the material property, shape, and dimensions of the roof-rail rotation braking plate 35, the rotation-braking plate setting step S7, the side-crash test model analysis step S9, and the rotation-angle comparison step S11 are repeatedly performed. When the rotation angles compared at the rotation-angle comparison step S11 are within the predetermined range, the material property, shape, and dimensions of the roof-rail rotation braking plate 35 at that time are determined as the test conditions of the side crash test of the center pillar 101 using the side crash test apparatus 1.
EXAMPLES
(84) Specific experiments to confirm the action and effect of the present invention were conducted, and this will be described below.
First Example
(85) In a first example, as illustrated in
(86) In the crash test structure 120, the roof-rail simulated part 123 is obtained by cutting the roof rail of the above-described commercial vehicle at a cross-section perpendicular to the vehicle longitudinal direction in front and rear of the portion connected to the center pillar 121, and disc-shaped roof-rail rotation support members 127 are joined to the front end and the rear end of the roof-rail simulated part 123 and the roof-rail rotation support members 127 are each provided with a roof-rail rotation shaft 129 projecting outward from the rotation center thereof.
(87) Similarly, the rocker simulated part 125 is obtained by cutting the rocker of the above-described commercial vehicle at a cross-section perpendicular to the vehicle longitudinal direction in front and rear of the portion connected to the center pillar 121, and disc-shaped rocker-rotation support members 131 are joined to the front end and the rear end of the rocker simulated part 125 and the rocker-rotation support members 131 are each provided with a rocker rotation shaft 133 projecting outward from the rotation center thereof.
(88) Then, one end side of a rocker-rotation braking plate that is a rectangle shape metal sheet having a sheet width of 25 mm is attached on the outer peripheral surface of each of the rocker-rotation support members 131, and the other end side of the rocker-rotation braking plate is fixed, so that the rotation of the rocker-rotation support members 131 is braked.
(89) In the commercially available real vehicle that was the test target in the first example, in the crash test result conducted under the side crash test conditions of the U.S. IIHS, the intrusion of the door hinge (upper side) of the center pillar was 125 mm and the rotation angles of the roof rail and the rocker were 3? and 24?, respectively.
(90) As just described, because the rotation angle of the roof rail is as small as 3?, in the first example, the roof-rail simulated part 123 of the crash test structure 120 was to be supported by the roof rail support 5 (see
(91) Meanwhile, as for the rocker simulated part 125, it was to be supported using the rocker supports 7 (see
(92) Then, the FEM analysis in which the striker 3 is made to crash into the side of the center pillar 121 was performed, and the rotation angle of the rocker-rotation support member attached to the rocker simulated part was obtained. In the first example, the FEM analyses of the side crash tests were conducted while changing the material and thickness of the rocker-rotation braking plate that brakes the rotation of the rocker-rotation support members 131. Table 1 indicates the material and sheet thickness set as the parameters of the rocker-rotation braking plate.
(93) TABLE-US-00001 TABLE 1 Rocker-rotation braking plate (rectangle shape) Sheet Rotation angle Symbol Material thickness Roof rail Rocker Real vehicle 3? 24? No. 1 None None 0? 50? No. 2 Oxygen-free copper 2 mm 0? 36? No. 3 Oxygen-free copper 4 mm 0? 24? No. 4 Oxygen-free copper 6 mm 0? 16? No. 5 Mild steel 2.3 mm 0? 29? No. 6 Mild steel 2.8 mm 0? 24? No. 7 Mild steel 3.2 mm 0? 21?
(94) The real vehicle in Table 1 is one for which the side crash test of the real vehicle was conducted and the rotation angles of the roof rail and the rocker of the vehicle were obtained. Meanwhile, No. 1 to No. 7 in Table 1 are the results, obtained by the FEM analyses using the side crash test model that modeled the crash test structure 120, of the rotation angles of the roof-rail rotation support members 127 and the rocker-rotation support members 131, the roof-rail rotation support members 127 being attached to the respective end faces of the front end and the rear end of the roof-rail simulated part 123 and the rocker-rotation support members 131 being attached to the respective end faces of the front end and the rear end of the rocker simulated part 125. Then, No. 1 is one for which the rocker-rotation braking plates were not attached to the rocker-rotation support members 131 neither, and the rocker simulated part 125 was to be rotatable freely without applying the braking to the rotation about the axis thereof. No. 2 to No. 7 are ones for which the rocker-rotation braking plates were attached to the rocker-rotation support members 131, and the braking was applied to the rotation about the axis of the rocker simulated part 125. Then, No. 2 to No. 4 are ones for which the sheet thickness was changed with the material of the rocker-rotation braking plate being oxygen-free copper, and No. 5 to No. 7 are ones for which the sheet thickness was changed with the material of the rocker-rotation braking plate being mild steel.
(95) The foregoing Table 1 indicates the results of the rotation angle obtained in the side crash tests. From Table 1, in the case of No. 1 where no braking was applied to the rotation of the rocker simulated part 125, it is found that the rotation of the rocker simulated part 125 was excessive as compared with the real vehicle. Meanwhile, in any of the cases of No. 2 to No. 4 for which the material of the rocker-rotation braking plate was oxygen-free copper and the cases of No. 5 to No. 7 with mild steel, it is found that the braking applied to the rotation of the rocker simulated part 125 was increased by increasing the sheet thickness and that the rotation angle of the rocker simulated part 125 became small.
(96) Then, as the parameters of the rocker-rotation braking plate that substantially matches the rotation angle) (=24?) of the rocker in the side crash test of the real vehicle, (a) oxygen-free copper of a sheet width 25 mm?sheet thickness 4 mm or (b) mild steel of a sheet width 25 mm?sheet thickness 2.8 mm were determined.
(97)
(98) From
(99)
(100) From
Second Example
(101) In a second example, based on the results obtained in the first example by the side crash test condition determination method for a center pillar of an automobile according to the present invention, the side crash test of the crash test structure 120 illustrated in
(102) The rocker-rotation braking plate 25 used in the second example was a dumbbell-shaped metal sheet having the parallel portion 25a illustrated in
(103) Then, each end of the fabricated dumbbell-shaped rocker-rotation braking plate 25 was attached to the outer peripheral surface of the disc-shaped rocker-rotation support member 131. In the second example, the side crash tests were conducted using the side crash test apparatus 1 illustrated in
(104) The crash test structure 120 was of the same structures and materials as those of the center pillar 121, the roof-rail simulated part 123, and the rocker simulated part 125 used in the FEM analyses of the side crash tests in the first example.
(105) Table 2 indicates the results of the rotation angle of the rocker simulated part 125 at the time the intrusion of the door hinge (upper side) of the center pillar 121 reached 125 mm.
(106) TABLE-US-00002 TABLE 2 Rocker-rotation braking plate (dumbbell shape) Sheet Rotation angle Symbol Material thickness Roof rail Rocker Real vehicle 3? 24? First example Oxygen-free 4 mm 0? 24? copper Second example Mild steel 2.8 mm 0? 25?
(107) The rotation angle of the rocker-rotation support members 131 attached to the end faces of the front end and the rear end of the rocker simulated part 125 was 25?, and it substantially matched with the result of the real vehicle illustrated in the foregoing first example and the result of the FEM analysis for which the rocker-rotation braking plate was of the rectangle shape metal sheet.
(108) In addition, the deformed shapes of the center pillar in the side crash tests, as illustrated in
(109) Moreover,
(110) From
INDUSTRIAL APPLICABILITY
(111) According to the present invention, it is possible to provide a side crash test apparatus and a side crash test condition determination method for a center pillar of an automobile, being capable of reproducing the destructive phenomenon of the center pillar that arises in the side crash test of a real vehicle by a simpler mechanism and simpler condition adjustment.
REFERENCE SIGNS LIST
(112) 1 SIDE CRASH TEST APPARATUS 3 STRIKER 3a LOWER PUNCH 3b UPPER PUNCH 5 ROOF RAIL SUPPORT 7 ROCKER SUPPORT 9 ROCKER-ROTATION BRAKING MECHANISM 11 LOAD CELL 13 ROOF-RAIL POSITION ADJUSTMENT MEMBER 15 LOAD CELL 17 ROCKER-POSITION ADJUSTMENT MEMBER 19 ROCKER-ROTATION SUPPORT MEMBER 19a ARC SURFACE 21 ROCKER ROTATION SHAFT 23 ROCKER-ROTATION SHAFT SUPPORT 25 ROCKER-ROTATION BRAKING PLATE 27 ROCKER-ROTATION BRAKING PLATE FIXED PORTION 29 ROOF RAIL SUPPORT 31 ROOF-RAIL ROTATION BRAKING MECHANISM 33 ROOF-RAIL ROTATION SUPPORT MEMBER 33a ARC SURFACE 35 ROOF-RAIL ROTATION BRAKING PLATE 37 ROOF-RAIL ROTATION BRAKING PLATE FIXED PORTION 41 ROCKER SUPPORT 43 ROCKER-ROTATION BRAKING MECHANISM 45 ROCKER-ROTATION SUPPORT MEMBER 45a ARC SURFACE 45b CIRCUMFERENTIAL FACE 47 ROCKER-ROTATION SHAFT SUPPORT 47a SUPPORT PLATE MEMBER 47b HOLE 100 CRASH TEST STRUCTURE 101 CENTER PILLAR 101a UPPER PORTION 101b LOWER PORTION 103 ROOF-RAIL SIMULATED PART 105 ROCKER SIMULATED PART 107 FIXING PLATE 109 DISC 110 SIDE-CRASH TEST MODEL 120 CRASH TEST STRUCTURE 121 CENTER PILLAR 123 ROOF-RAIL SIMULATED PART 125 ROCKER SIMULATED PART 127 ROOF-RAIL ROTATION SUPPORT MEMBER 129 ROOF-RAIL ROTATION SHAFT 131 ROCKER-ROTATION SUPPORT MEMBER 133 ROCKER ROTATION SHAFT