AU2011253883B2

AU2011253883B2 - Vehicle knee bolster

Info

Publication number: AU2011253883B2
Application number: AU2011253883A
Authority: AU
Inventors: Yusuke Fujiwara
Original assignee: Toyota Motor Corp
Current assignee: Toyota Motor Corp
Priority date: 2010-12-03
Filing date: 2011-12-07
Publication date: 2013-05-30
Anticipated expiration: 2031-12-07
Also published as: BRPI1105635B1; JP2012116437A; AU2011253883A1; BRPI1105635A2; CN102485549B; CN102485549A; JP5136630B2

Abstract

VEHICLE KNEE BOLSTER Abstract A resin energy-absorbing member (14) that constitutes a vehicle knee bolster is s formed in an elliptical shape in cross-section when viewed from a metal bracket (22) at a dashboard reinforcement (12), and is formed in a shape of a tube one end of which opens toward the metal bracket (22) and the other end of which is closed. The energy-absorbing member (14) is fixed to the fixed portion (22), at both end sides of an opening edge in the direction of the major axis of the elliptical cross-section. When crushing under load from 1o a knee (P1) of an occupant (P) in the event of a vehicle collision, etc., the energy absorbing member (14) dynamically changes its sectional shape, thereby dispersing stress. Thus, it is possible to prevent breaking of the energy-absorbing member (14), thereby stabilizing the load-displacement characteristic. Further, it is possible to increase the length of the energy-absorbing member (14), thereby reducing the length of the metal 15 bracket (22). Ca 0)0 CLLa 0 I4c U-o

Description

S&F Ref: P014687 AUSTRALIA PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT Name and Address Toyota Jidosha Kabushiki Kaisha, of 1, Toyota-cho, of Applicant: Toyota-shi, Aichi-ken, 471-8571, Japan Actual Inventor(s): Yusuke Fujiwara Address for Service: Spruson & Ferguson St Martins Tower Level 35 31 Market Street Sydney NSW 2000 (CCN 3710000177) Invention Title: Vehicle knee bolster The following statement is a full description of this invention, including the best method of performing it known to me/us: 5845c(5815661_1) 1 VEHICLE KNEE BOLSTER Technical Field The invention relates to a vehicle knee bolster that restrains the knees of an occupant in the event of, for example, a vehicle collision. Background of the Invention Japanese Patent Application Publication No. 2003-312419 (JP-A-2003-312419) describes an automobile knee bolster that is formed of a rigid urethane pad (energy absorbing member). The rigid urethane pad is supported by a dashboard reinforcement via a metal bracket, and is disposed to face the knee of an occupant. In the event of an automobile collision, the rigid urethane pad crushes under load from the knee of the occupant, thereby absorbing knee impact energy. However, current technology for producing rigid urethane pads limits the lengths of foamed products. In addition, rigid urethane pads easily break while being crushed (easily break under compressive loads). Therefore, it is not possible to form very long rigid urethane pads. Thus, it is not possible to reduce the lengths of metal brackets (fixed portions) to which the rigid urethane pads are fixed. Accordingly, there is room for further mass reduction. In addition, the load-displacement characteristic of a rigid urethane pad may vary greatly because the rigid urethane pad easily breaks under compressive load as described above. Object of the Invention It is the object of the present invention to substantially overcome or at least ameliorate one or more of the foregoing disadvantages. Summary of the Invention The present invention relates to a vehicle knee bolster that includes a resin energy-absorbing member that is arranged in front of a knee of an occupant seated in a seat of a vehicle, and that is fixed at its front end to a fixed portion provided at a rigid member on the vehicle body side. The energy-absorbing member is formed in an oval shape in cross-section when viewed from the fixed portion side, and is formed in a shape of a tube one end of which opens toward the fixed portion and the other end of which is closed. The energy-absorbing member is fixed to the fixed portion, at both end sides of an opening edge in the direction of the major axis of the oval cross-section. The energy-absorbing member is formed such that a wall thickness at each of both ends in the direction of the major axis of the oval cross-section is larger than a wall thickness at each of both ends in a direction of a minor axis of the oval cross-section.

2 Note that examples of "oval shape" include an elliptical shape, a rectangular shape with rounded corners, and an egg shape. In an embodiment of the present invention, the energy-absorbing member is fixed at its front end to the fixed portion provided at the rigid member (e.g., dashboard reinforcement) on the vehicle body side. In the event of, for example, a vehicle collision, the energy-absorbing member crushes under load from the knee of the occupant who is displaced toward the front of the vehicle due to inertial force. Thus, knee impact energy is absorbed. Further, the energy-absorbing member is formed in an oval shape in cross-section when viewed from the fixed portion side, and is formed in a shape of a tube one end of which opens toward the fixed portion and the other end of which is closed. The energy absorbing member is fixed to the fixed portion, at both end sides of the opening edge in the direction of the major axis of the oval cross-section. With this structure at least according to a preferred embodiment, when the energy absorbing member crushes, stress is concentrated on its both ends in the direction of the major axis of the oval cross-section, namely, on both ends at which the curvature is largest in a peripheral wall of the energy-absorbing member. Due to this stress concentration, the energy-absorbing member is buckled in the manner of an accordion such that the both ends at which the curvature is large form buckling waves. At this time, the energy-absorbing member deforms in the following manner. Portions of the energy-absorbing member, which correspond to peaks of the buckling waves, deform such that the major axis of the oval cross-section increases. On the other hand, portions of the energy-absorbing member, which correspond to troughs of the buckling waves, deform such that the minor axis of the oval cross-section increases. Such dynamic changes in the sectional shape of the energy absorbing member disperse stress. This makes it possible to prevent or effectively suppress occurrence of breaking of the energy-absorbing member due to buckling of the energy absorbing member. Consequently, it is possible to stabilize the load-displacement characteristic of the energy-absorbing member. In addition, breaking of the energy-absorbing member can be prevented, which makes it possible to set the length of the energy-absorbing member to a large value. Thus, it is possible to simplify the structure of the fixed portion, thereby reducing the mass of a lower leg restraining device. For example, when a metal bracket attached to a main body (e.g., pipe) of the dashboard reinforcement is used as the fixed portion, it is possible to reduce the length of the metal bracket. If part of the main body of the dashboard reinforcement is used as the fixed portion and the energy-absorbing member is directly fixed to the fixed portion, it is possible to omit the metal bracket. Thus, it is possible to reduce the mass of the lower leg restraining device.

3 Further, at least according to a preferred embodiment, when the energy-absorbing member crushes, stress is concentrated on both ends in the direction of the major axis of the oval cross-section. However, the wall thickness at each of both ends in the direction of the major axis of the oval cross-section is larger than the wall thickness at each of both ends in the direction of the minor axis of the oval cross-section, and it is therefore possible to prevent occurrence of breaking at both ends in the direction of the major axis of the oval cross-section due to excess stress concentration. In the vehicle knee bolster described above, the energy-absorbing member may be formed in an elliptical shape in cross-section when viewed from the fixed portion side, and the ratio of the length of the major axis of the elliptical cross-section to the length of the minor axis of the elliptical cross-section may be set to 2 to 1. In the energy-absorbing member, the ratio of the length of the major axis (longer axis) of the elliptical cross-section to the length of the minor axis (shorter axis) of the elliptical cross-section is set to 2 to 1. This makes it possible to minimize the mass of the energy-absorbing member while ensuring the amount of energy that the energy-absorbing member is required to absorb. In the vehicle knee bolster described above, the energy-absorbing member is fixed to the fixed portion with the major axis of the oval cross-section extending along the vehicle height direction. The energy-absorbing member is disposed with the major axis of the oval cross section extending along the vehicle height direction, and the dimension of the energy absorbing member in the vehicle height direction is set to a large value. Therefore, the energy-absorbing member appropriately faces the knee regardless of variations in the height of the knees due to, for example, variations in physical sizes of occupants. In the vehicle knee bolster described above, a configuration may be employed, in which, from each of both ends of the energy-absorbing member in the direction of the major axis of the oval cross-section of the energy-absorbing member, a fastened portion extends. With this configuration, it is made easier to fix the energy-absorbing member to the fixed portion. The fastened portion may extend in a direction parallel with a minor axis of the oval cross-section. Arranging the fastened portions in this manner makes it possible to reduce the dimension of the energy-absorbing member along direction of the major axis of the elliptical cross-section. Accordingly, it is possible to use a more compact and less expensive mold for forming the energy-absorbing member. The fastened portion may extend toward a front of the vehicle. Arranging the fastened portions in this manner makes 4 it possible to fix the energy-absorbing member directly to a beam-like member or the like that extends in the vehicle width direction. As described above, with the vehicle knee bolster according to an embodiment of the invention, it is possible to stabilize the load-displacement characteristic of the energy 5 absorbing member and to achieve a mass reduction. Brief Description of the Drawings Features, advantages, and technical and industrial significance of exemplary embodiments of the invention will be described below with reference to the accompanying 10 drawings, in which like numerals denote like elements, and wherein: FIG. 1 is a perspective view showing the structure of a vehicle knee bolster according to a first embodiment of the invention; FIG. 2 is an exploded perspective view showing the partial structure of the vehicle knee bolster according to the first embodiment of the invention; 15 FIG. 3 is an enlarged sectional view taken along the line III-III in FIG. 1; FIG. 4 is an enlarged sectional view taken along the line IV-IV in FIG. 1; FIG. 5A is a schematic perspective view illustrating a mode of deformation of an energy-absorbing member according to the first embodiment of the invention, the deformation being caused when the energy-absorbing member is buckled; 20 FIG. 5B is a schematic sectional view illustrating the mode of deformation of the energy-absorbing member at a cross-section along the line B-B in FIG. 5A; FIG. SC is a schematic sectional view illustrating the mode of deformation of the energy-absorbing member at a cross-section along the line C-C in FIG. SA; FIG. 6 is a graph showing the load-displacement characteristics of energy 2s absorbing members; FIG. 7 is a front view showing the structure of an energy-absorbing member according to a second embodiment of the invention; and FIG. 8 is a perspective view showing the partial structure of a vehicle knee bolster according to a third embodiment of the invention. 30 Detailed Description of Embodiments (First Embodiment) Hereafter, a vehicle knee bolster 10 according to a first embodiment of the invention will be described with reference to FIGs. 1 to 6. In the drawings, an arrow FR 35 indicates the direction toward the front of a vehicle, an arrow UP indicates the direction 5 toward the top of the vehicle, an arrow LH indicates the direction toward the left side of the vehicle, and an arrow RH indicates the direction toward the right side of the vehicle. The vehicle knee bolster 10 according to the first embodiment of the invention is a device (lower leg restraining device) that restrains the knees of an occupant seated in a s driver seat of a right-hand drive vehicle in the event of, for example, a vehicle collision. As shown in FIG. 1, the vehicle knee bolster 10 includes a dashboard reinforcement 12 and a pair of right and left energy-absorbing members 14. The dashboard reinforcement 12 is disposed on the inner side of a dashboard (not shown) provided at the front portion of a vehicle compartment, and extends in the vehicle lateral direction to connect right and left io vehicle body panels to each other . Note that FIG.1 shows only part of the dashboard reinforcement 12. A main body 18 of the dashboard reinforcement 12 is formed of a long metal pipe. The main body 18 is thick at its driver seat-side portion that is required to have high strength, and is thin at its passenger seat-side portion that is not required to have very high 15 strength. A metal column support portion 20 (column bracket) that supports a steering column is attached to the driver seat-side portion of the main body 18. The right and left metal brackets 22 are disposed on the right and left sides of the column support portion 20, respectively. The metal brackets 22 are fixed portions to which the energy-absorbing members 14 are fixed. :2a Each metal bracket 22 is formed to have an open cross-section (formed in a U shape in cross-section), by bending a metal sheet. As shown in FIG. 2, each metal bracket 22 has an upper wall 22A, a lower wall 22B, and a vertical wall 22C. The metal brackets 22 are symmetrically formed, and both of the metal brackets 22 open toward the column support portion 20. Each metal bracket 22 is formed such that its vertical dimension 25 decreases toward its front end. Each metal bracket 22 is welded at its front end portions to the main body 18 of the dashboard reinforcement 12. An upper fastened piece 22D extends upward from the rear end of the upper wall 22A of the metal bracket 22, and a lower fastened piece 22E extends downward from the rear end of the lower wall 22B of the metal bracket 22. The energy-absorbing member 14 30 is fixedly fastened to the upper fastened piece 22D and the lower fastened piece 22E. The energy-absorbing member 14 is formed in a shape of a tube with a closed end, by subjecting resin material to injection molding. The energy absorbing member 14 is disposed with an opening 14A facing the metal bracket 22 and with a bottom wall 14B facing the dashboard (not shown). Note that synthetic resin materials that have high 35 elongation resistance and low temperature dependence, such as polypropylene to which 6 multiple types of rubbers are added, are suitable as the materials for the energy-absorbing members 14. Each energy-absorbing member 14 is formed in an elliptical shape in cross-section when viewed from the metal bracket 22-side, and formed in a tapered shape (in a shape of s a generally truncated cone) such that the perimeter of a peripheral wall 14C decreases toward the bottom wall 14B (rear end). As shown in FIG. 3, the ratio of the length of a major axis dl (longer axis) of the elliptical cross-section of the energy-absorbing member 14 to that of a minor axis d2 (shorter axis) of the elliptical cross-section is set to 2 to 1. In addition, the peripheral wall 14C of the energy-absorbing member 14 is formed such that a 10 wall thickness ti at each of both ends in the direction of the major axis of the elliptical cross-section is larger than a wall thickness t2 at each of both ends in the direction of the minor axis of the elliptical cross-section. Each energy-absorbing member 14 is disposed with the major axis dl of the elliptical cross-section extending along the vehicle height direction. An upper fastened is portion 14D extends upward from a top portion of an opening edge of the energy absorbing member 14. A lower fastened portion 14E extends downward from a bottom portion of the opening edge of the energy-absorbing member 14. A circular through-hole 24 is formed in the upper fastened portion 14D. A screw 28 passed through the circular through-hole 24 is screwed into a threaded hole 32 formed 2!0 in the upper fastened piece 22D of the metal bracket 22. Thus, the upper fastened portion 14D is fixedly fastened to the upper fastened piece 22D. Similarly, a circular through-hole 26 is formed in the lower fastened portion 14E. A screw 30 passed through the circular through-hole 26 is screwed into a threaded hole 34 formed in the lower fastened piece 22E of the metal bracket 22. Thus, the lower fastened portion 14E is fixedly fastened to the :5 lower fastened piece 22E. Accordingly, the energy-absorbing member 14 is fixed to the metal bracket 22, at both end sides of the opening edge in the direction of the major axis of the elliptical cross section, and is not fixed to the metal bracket 22 at either of the end sides of the opening edge in the direction of the minor axis of the elliptical cross-section. In other words, the 30 opening edge of the energy-absorbing member 14 is fixed to the metal bracket 22 at only two points, that is, the top and bottom points, and the left and right portions of the opening edge are free (are deformable). In FIG. 2, a line denoted by PL is a parting line formed during injection molding of the energy-absorbing member 14. Parting lines PL are formed at the top and bottom of 7 the peripheral wall 14C. The parting lines PL are located on the peripheral wall 14C at both ends in the direction of the major axis dl of the elliptical cross-section. The thus structured vehicle knee bolster 10 is configured such that, when an occupant P is seated in the driver seat of the vehicle, the left energy-absorbing member 14 is disposed in front of a left knee P1 of the occupant P and the right energy-absorbing member 14 is disposed in front of a right knee P1 of the occupant P, as shown in FIG. 1. Next, the operations and effects of the first embodiment will be described. According to the first embodiment, if the occupant P is displaced forward relative to the vehicle body due to inertial force in the event of, for example, a frontal vehicle 1) collision, the knees P1 of the occupant P hit the energy-absorbing members 14 via the dashboard (not shown). Thus, the energy-absorbing members 14 crush under loads from the knees P1 of the occupant P while receiving, from the metal brackets 22, reaction force directed toward the rear of the vehicle. At this time, the energy-absorbing members 14 generate loads, whereby impact energy of the knees P1 is absorbed and the lower legs of 1. the occupant P are restrained. Each energy-absorbing member 14 is formed in an elliptical shape in cross-section when viewed from the metal bracket 22-side, and formed in a shape of a tube one end of which is closed and the other end of which opens toward the metal bracket 22. The energy-absorbing member 14 is fixed to the metal bracket 22 at both end sides of the 23 opening edge in the direction of the major axis of the elliptical cross-section. Therefore, when each energy-absorbing member 14 crushes, stress is concentrated on its both ends in the direction of the major axis of the elliptical cross-section, namely, on both ends at which the curvature is largest in the peripheral wall 14C (the portions at which the upper and lower parting lines PL are located, in the first embodiment). Due to this 25 stress concentration, as indicated by the solid line in FIG. 5A, the energy-absorbing member 14 is buckled in the manner of an accordion such that the portions at the upper and lower parting lines PL form buckling waves. At this time, a substantial change in the perimeter of the peripheral wall 14C does not occur. Therefore, the energy-absorbing member 14 deforms in the following manner. 30 Portions of the energy-absorbing member 14, which correspond to peaks of the buckling waves, deform such that the major axis of the elliptical cross-section increases, as shown in FIG. 5C. On the other hand, portions of the energy-absorbing member 14, which correspond to troughs of the buckling waves, deform such that the minor axis of the elliptical cross-section increases, as shown in FIG. 5B. Such dynamic changes in the 35 sectional shape of the energy-absorbing member 14 disperse stress. This makes it possible 8 to prevent breaking of the energy-absorbing member 14, which otherwise would occur as the energy-absorbing member 14 is buckled. Consequently, it is possible to stabilize the load-displacement characteristic of the energy-absorbing member 14. In FIG. 6, the solid line indicates the load-displacement characteristic of an . energy-absorbing member when the energy-absorbing member does not break, and the broken line indicates the load-displacement characteristic of an energy-absorbing member when the energy-absorbing member breaks. It is clear from FIG. 6 that the load drops when the energy-absorbing member breaks (see a region E in FIG. 6). This significantly reduces the amount of energy absorbed by the energy-absorbing member. However, such 10 reduction in the amount of energy absorption is avoided according to the first embodiment. Moreover, according to the first embodiment, it is possible to set a length L (see FIG. 4) of the energy-absorbing member 14 to a large value because the energy-absorbing member 14 is prevented from breaking as described above. This makes it possible to significantly reduce the length of each metal bracket 22 provided at the dashboard is reinforcement 12. As a result, it is possible to reduce the mass of the lower leg restraining device. The first embodiment also offers high design flexibility, because it is possible to flexibly adjust the magnitude of load generated by the energy-absorbing member 14 and the stroke (the amount of displacement) of the energy-absorbing member 14 when it 20 crushes, by changing the length, material, and wall thickness of the energy-absorbing member 14 as needed. According to the first embodiment, the energy-absorbing member 14 is formed such that the wall thickness t1 at each of both ends in the direction of the major axis of the elliptical cross-section is larger than the wall thickness t2 at each of both ends in the 1s direction of the minor axis of the elliptical cross-section. Therefore, even if stress is concentrated on both ends in the direction of the major axis of the elliptical cross-section when the energy-absorbing member 14 crushes, it is possible to prevent occurrence of breaking at both ends in the direction of the major axis of the elliptical cross-section due to excess stress concentration. :10 According to the first embodiment, the ratio of the length of the major axis dl of the elliptical cross-section of the energy-absorbing member 14 to that of the minor axis d2 of the elliptical cross-section is set to 2 to 1. This makes it possible to minimize the mass of the energy-absorbing member 14 while ensuring the amount of energy that the energy absorbing member 14 is required to absorb (the amount of energy absorption per unit mass 35 is maximized).

9 Furthermore, the energy-absorbing member 14 according to the first embodiment. is fixed to the metal bracket 22 with the major axis dI of the elliptical cross-section extending along the vehicle height direction. That is, the dimension of the energy absorbing member 14 in the vehicle height direction is set to a large value. Therefore, the 5 energy-absorbing member 14 appropriately faces the knee P1 regardless of variations in the height of the knees P1 due to, for example, variations in physical sizes of occupants P. Moreover, it is possible to prevent the energy-absorbing member 14 from contacting, for example, the steering column. This structure is preferable in terms of securing the space in which the energy-absorbing member 14 is arranged. F) Next, other embodiments of the invention will be described. Note that substantially the same structures and operations as those in the first embodiment will be denoted by the same reference numerals as those in the first embodiment, and description thereof will be omitted below. (Second Embodiment) is FIG. 7 is a front view showing an energy-absorbing member 50 that is a component of a vehicle knee bolster according to a second embodiment of the invention. The energy-absorbing member 50 is structured in basically the same manner as the energy absorbing member 14 according to the first embodiment. However, the energy-absorbing member 50 has the upper fastened portion 14D that extends toward one side in the 20 direction of the minor axis of the elliptical cross-section, and the lower fastened portion extends toward the other side in the direction of the minor axis of the elliptical cross section. Arranging the upper fastened portion 14D and the lower fastened portion 14E in this manner makes it possible to reduce the dimension of the energy-absorbing member 50 along direction of the major axis of the elliptical cross-section. Accordingly, it is possible 25 to use a more compact and less expensive mold for forming the energy-absorbing member 50. In this case, the arrangement of the upper fastened piece 22D and lower fastened piece 22E of the metal bracket 22 need to be changed in accordance with the arrangement of the upper fastened portion 14D and the lower fastened portion 14E. (Third Embodiment) 1'o FIG. 8 is a perspective view of the partial structure of a vehicle knee bolster according to a third embodiment of the invention. The knee bolster according to the third embodiment is structured in basically the same manner as the knee bolster 10 according to the first embodiment. However, the metal brackets 22 according to the first embodiment are omitted in the third embodiment. Further, the structure of an energy-absorbing 10 member 60 is different from that of the energy-absorbing member 14 according to the first embodiment. The energy-absorbing member 60 is formed in a tapered shape (in a shape of a generally truncated cone) such that the perimeter of the peripheral wall 14C increases toward the bottom wall 14B (rear end). The front end portion of the energy-absorbing member 60 (end portion on the opening 14A-side) is in contact with a fixed portion 62 which is formed in the main body 18 of the dashboard reinforcement 12. The upper fastened portion 14D is curved so as to tightly conform to the upper surface of the fixed portion 62. The screw 28 passed through the upper fastened portion 14D is screwed into a 1o threaded hole (not shown) which is formed in an upper portion of the fixed portion 62. Thus, the upper fastened portion 14D is fixedly fastened to the fixed portion 62 (part of the main body 18). Similarly, the lower fastened portion 14E is curved so as to tightly conform to the lower surface of the fixed portion 62. The screw 30 passed through the lower fastened portion 14E is screwed into a threaded hole (not shown) which is formed in 15 a lower portion of the fixed portion 62. Thus, the lower fastened portion 14E is fixedly fastened to the fixed portion 62 (part of the main body 18). According to the third embodiment, part of the main body 18 of the dashboard reinforcement 12 is used as the fixed portion 62 to which the energy-absorbing member is fastened as described above, and therefore the main body 18 directly receives reaction 20 force from the energy-absorbing member 60. This makes it possible to omit the metal brackets 22, thereby significantly reducing the mass of the lower leg restraining device. In each of the embodiments described above, the energy-absorbing member 14 is arranged with the major axis dl of the elliptical cross-section extending along the vehicle height direction. However, the manner of arranging the energy-absorbing member 14 is 25 not limited to this, in the invention. For example, the energy-absorbing member 14 may be arranged with the major axis dl of the elliptical cross-section extending along the vehicle lateral direction or with the major axis dl of the elliptical cross-section tilted. In each of the embodiments described above, the ratio of the length of the major axis dI of the elliptical cross-section of the energy-absorbing member 14 to that of the 30 minor axis d2 of the elliptical cross-section is set to 2 to 1. However, the ratio of the length of the major axis dl to that of the minor axis d2 is not limited to this, in the invention. The manner of setting the elliptical cross-section of the energy-absorbing member may be adjusted as needed, and the ratio of the length of the major axis to that of the minor axis need not be limited to exactly 2:1.

In each of the embodiments described above, the energy-absorbing member 14 is formed such that the wall thickness tI at each of both ends in the direction of the major axis of the elliptical cross-section is larger than the wall thickness t2 at each of both ends in the direction of the minor axis of the elliptical cross-section. However, in the invention, the manner of setting the wall thickness of the energy-absorbing member is not limited to this, and may be changed as needed. In each of the embodiments described above, the energy-absorbing member 14 is formed in an elliptical shape in cross-section when viewed from the metal bracket 22-side. However, in this invention, the sectional shape of the energy-absorbing member 14 is not 1o limited to this. The energy-absorbing member 14 may be formed in a shape of a rectangle with rounded corners or an egg shape when viewed from the fixed portion side. In each of the embodiments described above, the energy-absorbing member 14 is formed through injection molding. However, in this invention, the manner of forming the energy-absorbing member 14 is not limited to this, and may be changed as needed. I, In each of the embodiments described above, the fixed portions (metal brackets 22 or fixed portions 62) are formed at the dashboard reinforcement 12. However, in this invention, the positions of the fixed portions are not limited to these. For example, the fixed portions may be formed at a floor brace that connects the dashboard reinforcement 12 to the vehicle floor. 20 In each of the embodiments described above, the vehicle knee bolster 10 is adopted for use on the driver seat of right-hand drive vehicles. However, in this invention, the use of the vehicle knee bolster 10 is not limited to this. The vehicle knee bolster may be adopted for use on either one of the left and right seats of the vehicle. The invention may be implemented in various other embodiments within the 2. scope of the invention. It is needless to say that the scope of the invention is not limited to any of the above-described embodiments.

Claims

1. A vehicle knee bolster, comprising a resin energy-absorbing member that is arranged in front of a knee of an occupant seated in a seat of a vehicle, and that is fixed at a front end to a fixed portion provided at a rigid member on a vehicle body side, wherein: the energy-absorbing member is formed in an oval shape in cross-section when viewed from the fixed portion, and is formed in a shape of a tube one end of which opens toward the fixed portion and the other end of which is closed; the energy-absorbing member is fixed to the fixed portion, at both end sides of an opening edge in a direction of a major axis of the oval cross-section; and the energy-absorbing member is formed such that a wall thickness at each of both ends in the direction of the major axis of the oval cross-section is larger than a wall thickness at each of both ends in a direction of a minor axis of the oval cross-section.

2. The vehicle knee bolster according to claim 1, wherein the energy absorbing member is formed in an elliptical shape in cross-section when viewed from a fixed portion side, and a ratio of a length of a major axis of the elliptical cross-section to a length of a minor axis of the elliptical cross-section is set to 2 to 1.

3. The vehicle knee bolster according to claim 1 or 2, wherein the energy absorbing member is fixed to the fixed portion with the major axis of the oval cross section extending along a vehicle height direction.

4. The vehicle knee bolster according to any one of claims 1 to 3, wherein, from each of both ends of the energy-absorbing member in the direction of the major axis of the oval cross-section of the energy-absorbing member, a fastened portion extends.

5. The vehicle knee bolster according to claim 4, wherein the fastened portion extends in a direction parallel with a minor axis of the oval cross-section.

6. The vehicle knee bolster according to claim 4, wherein the fastened portion extends toward a front of the vehicle. 13

7. A vehicle knee bolster substantially as hereinbefore described with reference to any one of the embodiments of a vehicle knee bolster as that embodiment is shown in one or more of the accompanying drawings. Toyota Technical Development Corporation Patent Attorneys for the Applicant/Nominated Person SPRUSON & FERGUSON