JP6037775B2 - Knee bolster structure - Google Patents

Description

  The present invention relates to a knee bolster structure for protecting an occupant's knee when a vehicle collides.

  The vehicle incorporates a knee bolster structure (also referred to as a knee protection device) for protecting the occupant's knee in the event of a collision. The knee bolster structure is often arranged on the front side of the vehicle from the instrument panel in front of the driver's seat and passenger seat. When the vehicle collides, the knee bolster structure receives the knees of the occupant moving forward in the front of the vehicle, absorbs the collision energy while deforming, and protects the knees.

  The knee protection device 100 disclosed in Patent Literature 1 is said to be lightweight and increase the amount of absorbed energy. FIG. 4A shows a side cross-sectional view of the knee protection device 100 of Patent Document 1. FIG. In the knee protection device 100, one end is fixed to the steering support member 122 and bent so as to be convex toward the upper side of the vehicle body, and one end is connected to the other end of the upper connection portion 132 before the front of the vehicle body. A load receiving portion 130 that inclines downward and extends linearly, and one end extends linearly from the other end of the load receiving portion 130 to the front of the vehicle body, and the other end is fixed to the steering support member 122. It is comprised from the downward connection part 134 bent so that it may become convex toward.

  Accordingly, the knee protection device 100 has a pentagonal cross-sectional shape having five bending points. The bending point is represented by a black circle.

  FIG. 4B shows a state in which the knee 136 has collided with the load receiving portion 130. The upper connecting portion 132 is deformed along the steering support member 122 and is bent so as to be convex upward. The lower connecting part 134 is bent so as to be convex downward. As described above, the upper connecting portion 132 and the lower connecting portion 134 are bent, so that it is possible to provide the knee protection device 100 that is small and has a large amount of collision energy absorption from the knee.

JP 10-044899 A (Patent No. 3887848)

  The knee protection device 100 of Patent Document 1 is small in size, but can almost use the moving distance from the load receiving portion 130 to the steering support member 122, and seems to be able to absorb impact energy greatly. However, the load receiving portion 130 is relatively small with respect to the apparatus, and depending on the occupant's physique and riding posture, the corner portion facing the knee may be convex instead of a flat surface, and the knee load may increase instead.

  In view of the above problems, the present invention provides a knee bolster structure that can take a wide load receiving portion and can effectively absorb impact energy.

More specifically, the knee bolster structure of the present invention is:
A knee bolster structure that absorbs the occupant's knee load at the time of collision by buckling the polygonal frame section in a side view of the vehicle body,
One end is fixed to the vehicle body structure, and a flat portion extending linearly toward the rear of the vehicle body,
It has three bending points in a cross-sectional side view of the vehicle body from the plane part,
A plate-like portion composed of a lower bent portion whose other end faces downward in front of the vehicle body,
A lower frame having
The lower surface of one end is connected to the vehicle body structure side from the bending point of the lower frame among the vehicle body upper side surfaces of the flat portion of the lower frame ,
Heading rearward and upward through one inflection point, with three inflection points in the car body side section,
An upper curved portion having a convex shape, the other end facing the front lower side of the vehicle body,
One end is connected to the other end of the upper curved portion,
The other end is a load receiving portion that extends linearly toward the lower front of the vehicle body,
An inner surface of the other end of the load receiving portion has an upper frame connected to an upper surface of the other end via a bending point of the lower frame;
The connection part of the upper frame and the lower frame is connected and fixed so as to be rotatable when receiving a knee load on the load receiving part ,
The lower frame extends in a direction perpendicular to the plate-like portion on the side surface of the plate-like portion in the vehicle width direction, and gradually decreases from the contact portion in contact with the vehicle body structure toward the rear of the vehicle body. It has the provided side bracket .

In the above-mentioned knee bolster structure ,
Before SL upper frame is,
A vertical wall is further provided on a side surface in the vehicle width direction of the upper bent portion and the load receiving portion.

  The present invention has seven buckling points in a cross-sectional view of the side surface of the vehicle body, and the lower frame and the upper frame are convex above the vehicle body, so the lower frame is buckled first, and then the upper frame is crushed. The impact can be absorbed gradually. Therefore, a large impact can be absorbed even if it is small.

  Moreover, since it can be set as a full load receiving part in the front view from the vehicle body rear, an impact load can be absorbed irrespective of a passenger | crew's physique and attitude | position.

1 is a perspective view of a knee bolster structure according to the present invention. It is a figure which shows the AA cross section of FIG. It is a figure which shows a mode that a knee bolster structure deform | transforms from the same viewpoint as FIG. It is a figure which shows the conventional knee protection device.

  The knee bolster structure of the present invention will be described below with reference to the drawings. The following description exemplifies an embodiment of the present invention, and changes within the scope of the present invention are included in the technical scope of the present invention without departing from the spirit of the present invention. Needless to say. Further, in the drawing, the front of the vehicle body is represented by an arrow F, the rear vehicle body is B, the upper vehicle body is U, the lower vehicle body is D, and the vehicle body width direction is W.

  FIG. 1 is a perspective view of a knee bolster structure according to the present invention. The knee bolster structure 1 includes a knee bolster body 10 connected and fixed to a vehicle body structure 3. The vehicle body structure 3 can suitably use a PP (pillar-to-pillar) member that can also be used as a steering support member. The knee bolster body 10 is connected to the vehicle body structure 3 by side brackets 23 a and 23 b that are joined at right angles to the vehicle body structure 3. The knee bolster main body 10 has a load receiving portion 16 in almost the entire surface as viewed from the rear of the vehicle body.

  A pair of knee bolster structures 1 can be provided on the driver side and the passenger seat side. Further, more may be provided.

  FIG. 2 is a cross-sectional view taken along the line AA in FIG. The plate-like portion 24 is attached so that the one end 24a is directed from the lower side of the vehicle body structure 3 toward the rear of the vehicle body. The plate-like portion 24 is bent with three bending points, a first bending point 29a, a second bending point 29b, and a third bending point 29c. As a result, the other end 24b of the plate-like portion 24 faces downward in front of the vehicle body. The flat portion 26 is formed from the one end 24a to the first bending point 29a.

  That is, the flat portion 26 is fixed below the vehicle body structure 3 and extends linearly toward the rear of the vehicle body in a cross-sectional side view of the vehicle body. Further, the first bent point 29a to the other end 24b are defined as the lower bent portion 28. That is, the plate-like portion 24 is composed of a flat portion 26 and a lower bent portion 28.

  Referring to FIG. 1 again, side brackets 23a and 23b are provided on both sides of the plate-like portion 24 in the vehicle width direction. The plate-like portion 24 and the side brackets 23a and 23b are joined by welding. The side brackets 23a and 23b are formed of plate members, and are joined to both sides of the plate-like portion 24 in the vehicle body width direction at a substantially right angle R1 with respect to the plate-like portion 24 (see reference numeral R1 in FIG. 1).

  The side brackets 23a and 23b are provided with contact portions 23m (23a and 23b are also denoted by the same reference numerals) that are welded to match the curvature of the vehicle body structure 3. The length with which the abutting portion 23m abuts the vehicle body structure 3 is not particularly limited. However, in the case of a PP member having a circular cross section as shown in FIG. Is desirable. This is to ensure the connection strength of the knee bolster structure 1 to the vehicle body structure 3.

  The widths 23w of the side brackets 23a and 23b (indicated by the same reference numerals for both 23a and 23b) gradually become narrower from the contact portion 23m toward the rear of the vehicle body. Here, the width 23w of the side brackets 23a and 23b is the length of a perpendicular line from the lower side 23g to the upper side 23t of the side brackets 23a and 23b on the rear side of the vehicle body structure 3.

  Referring to FIG. 2 again, the width 23w does not change from the first bending point 29a. The lower sides 23g of the side brackets 23a and 23b (both indicated by the same reference numerals as 23a and 23b) are joined along the plate-like portion 24. The plate-like portion 24 bends with the lower bent portion 28 having a bending point in a vehicle side cross-sectional view. Therefore, the lower side 23g of the side brackets 23a, 23b also has a bent point like the lower bent portion 28. Head backwards.

  The lower frame 22 is constituted by the plate-like portion 24 and the side brackets 23a and 23b.

  An upper frame 12 to which the lower surface of one end 12a is connected is disposed on the vehicle body upper surface 26u of the flat portion 26. This connection point is referred to as a first connection point 30. The upper frame 12 has a convex shape toward the rear upper side of the vehicle body via one bending point (fourth bending point 15a) that can be a separation point between the upper frame 12 and the lower frame 22 of the first connection point 30. It has a bent portion 14.

  That is, at the first connection point 30, the upper frame 12 having a bending point is connected to the flat portion of the flat portion 26 (lower frame 22). The upper bent portion 14 has three bent points, that is, a fifth bent point 15b, a sixth bent point 15c, and a seventh bent point 15d in order to form a convex shape. The other end 14b of the upper bent portion 14 is directed downward in the front of the vehicle body by the seventh bending point 15d. Note that one end 14 a of the upper bent portion 14 coincides with one end 12 a of the upper frame 12.

  One end 16 a of the load receiving portion 16 is connected to the other end 14 b of the upper bent portion 14. The load receiving portion 16 is a plane that is straight when viewed from the side of the vehicle body. Since the one end 16a of the load receiving portion 16 is continuously connected to the other end 14b of the upper bent portion 14, the load receiving portion 16 extends toward the front lower side of the vehicle body.

  The inner surface 16 i of the other end 16 b of the load receiving portion 16 is joined to the upper surface 28 u between the third bending point 29 c of the lower bent portion 28 and the other end 28 b of the lower bent portion 28. This connection point is referred to as a second connection point 32. At the second connection point 32, the lower bent portion 28 (lower frame 22) is connected to the plane portion of the load receiving portion 16 (upper frame 12) via a bending point. Here, the inner surface 16 i refers to the surface of the load receiving portion 16 that faces the upper curved portion 14. The upper bent portion 14 and the load receiving portion 16 constitute the upper frame 12.

  Further, vertical walls 18 a and 18 b (see also FIG. 1) that are perpendicular to the upper bent portion 14 and the load receiving portion 16 are provided on both sides of the upper bent portion 14 and the load receiving portion 16 in the vehicle width direction. Also good. The height from the upper bent portion 14 and the load receiving portion 16 to the end portions 18t of the vertical walls 18a and 18b (the vertical walls 18a and 18b are also indicated by the same reference numerals) is defined as the height 18h of the vertical wall. The height 18h of the vertical wall may be constant. However, it is not limited to being constant. This is because the height 18h of the vertical wall affects the crushing and strength of the upper frame 12, and the height 18h of the vertical wall may be intentionally changed depending on the location.

  Since the plate member is thick, it cannot be bent if it is bent. Even the bent part always has a curvature. In the knee bolster body 10 according to the present invention, main portions of the upper frame 12 and the lower frame 22 are formed by bending a single plate member. Therefore, the bending point is the intersection of the tangents of the curved surface of the bent plate member.

  For example, the upper bent portion 14 has a fifth bent point 15b, a sixth bent point 15c, and a seventh bent point 15d, which are not the plate member itself of the upper bent portion 14, but the plate member of the upper bent portion 14. Indicates the intersection of the tangent lines of the bent portion, the bent portion 14g, the bent portion 14h, and the bent portion 14i. Therefore, even if it is constituted by a continuous curve without a clear fold, there is a bending point. If it has a bending point, it can be said to be a broad polygon. Therefore, even if it comprises a continuous curve, it can be said that it has a polygonal shape if it has a plurality of bending points.

  In other words, it can be said that the upper bent portion 14 is composed of three large bent portions in a cross-sectional side view of the vehicle body, excluding the fourth bent portion 15a. Here, the radius of curvature of the curved portion 14i corresponding to the seventh bending point 15d is the smallest among the three curved portions. Further, the radius of curvature of the curved portion 14g corresponding to the fifth bending point 15b is formed to be the largest.

  Next, the operation of the knee bolster structure 1 of the present invention will be described. FIG. 3 shows a state in which the knee bolster structure 1 is crushed in a cross-sectional side view of the vehicle body as in FIG. FIG. 3A shows a state before an impact is applied to the load receiving portion 16. The impact is indicated by arrow 40. Here, the impact is, of course, the occupant's knee load. As described above, in the knee bolster structure 1 according to the present invention, almost the entire surface is the load receiving portion 16 when viewed from the rear of the vehicle body, so that the impact can be received even if the direction of the arrow 40 slightly changes.

  FIG. 3B shows a state where the load receiver 16 receives an impact 40 and the knee bolster body 10 starts to deform. The deformation starts from the first bending point 29 a of the lower frame 22. One end 26a of the flat portion 26 (one end 22a of the lower frame 22) is welded below the vehicle body structure 3, and is also fixed to the vehicle body structure 3 by the side bracket 23b. Therefore, the side near the one end 26a of the flat portion 26 is not deformed and bends upward toward the vehicle body at the point 26x between the first bending point 29a.

  The inner surface 16i of the load receiving portion 16 is connected to the upper surface 28u (see FIG. 2) of the lower bent portion 28. The second connection point 32 is connected via a third bending point 29c (see FIG. 2). Connected. On the upper frame 12 side, the radius of curvature of the curved portion 14i located on the rearmost side of the vehicle body is small. On the other hand, since the radius of curvature of the curved portion 14g is large, the curved portion 14g side is not easily deformed.

  Therefore, the second connection point 32 is directed to the bent flat portion 26 while rotating in the direction of the arrow V1 as the initial movement of the deformation. In this case, the pivot axis of rotation is the separation point 34 between the inner surface 16i and the upper surface 28u. Thus, it can be said that the second connection point 32 is rotatably connected and fixed when the load receiving portion 16 receives the impact 40.

  At this time, the curved portion 14g of the fifth bending point 15b and the curved portion 14h of the sixth bending point 15c of the upper frame 12 have a large radius of curvature, and are not easily deformed. As a result, the upper frame 12 is gently deformed and exerts an urging force in the impact direction. Therefore, it contributes to weakening the impact energy.

  When the second connection point 32 approaches the flat portion 26 and the lower frame 22 buckles at the first bending point 29a, the bent portion 14g of the upper bent portion 14 and the bent portion 14h start to buckle. That is, the curvature radius of the curvature of the upper frame 12 becomes small. Further, the vicinity of the first connection point 30 connected to the vehicle body upper surface 26u (see FIG. 2) of the fixed flat portion 26 via the fourth bending point 15a is bent from the fourth bending point 15a. As a result, the upper frame 12 itself falls in the V2 direction, which is the front of the vehicle body, and comes into contact with the vehicle body structure 3 (see FIG. 3C).

  During this time, buckling proceeds while bending the curved portions 14g and 14h having a large curvature radius, so that a large amount of energy is absorbed. Further, since the vertical wall 18 provided at a right angle to the buckling direction is buckled in a plane having a height of 18 h, it also absorbs a large amount of energy.

  In this way, a large impact energy can be absorbed by having two-stage deformation modes of buckling the lower frame 22, buckling the upper curved portion 14, and tilting the upper frame 12 itself toward the front of the vehicle body.

  The present invention can be suitably used for a knee bolster structure of an automobile.

1 Knee bolster structure 3 Body structure (PP member)
12 Upper frame 12a (upper frame) one end 10 Knee bolster body 14 Upper curved portion 14a (Upper curved portion) One end 14b (Upper curved portion) Other end 14g, 14h, 14i Bent portion 15a Fourth bending point 15b Fifth bending point Point 15c Sixth bending point 15d Seventh bending point 16 Load receiving portion 16a (Load receiving portion) One end 16b (Load receiving portion) Other end 16i Inner surface 18a, 18b Vertical wall 18t (Vertical wall) End portion 18h Vertical wall Height 22 lower frame 23a, 23b side bracket 23m (side bracket) contact portion 23w (side bracket) width 23g (side bracket) lower side 23t (side bracket) upper side 24 plate-like portion 24a (plate-like portion) One end 24b (of the plate-like portion) the other end 26 flat portion 26a (of the flat portion) one end 26u (of the flat portion) vehicle body upper surface 26x (at the flat portion) 2 Lower bending portion 28u Upper surface 29a (of lower bending portion) First bending point 29b Second bending point 29c Third bending point 30 First connection point 32 Second connection point 40 Impact 100 Knee protection device 122 Steering support member 130 Load receiving portion 132 Upper connecting portion 134 Lower connecting portion 136 Knee

Claims (2)

A knee bolster structure that absorbs the occupant's knee load at the time of collision by buckling the polygonal frame section in a side view of the vehicle body,
One end is fixed to the vehicle body structure, and a flat portion extending linearly toward the rear of the vehicle body,
It has three bending points in a cross-sectional side view of the vehicle body from the plane part,
A plate-like portion composed of a lower bent portion whose other end faces downward in front of the vehicle body,
A lower frame having
The lower surface of one end is connected to the vehicle body structure side from the bending point of the lower frame among the vehicle body upper side surfaces of the flat portion of the lower frame ,
Heading rearward and upward through one inflection point, with three inflection points in the car body side section,
An upper curved portion having a convex shape, the other end facing the front lower side of the vehicle body,
One end is connected to the other end of the upper curved portion,
The other end is a load receiving portion that extends linearly toward the lower front of the vehicle body,
An inner surface of the other end of the load receiving portion has an upper frame connected to an upper surface of the other end via a bending point of the lower frame;
The connection part of the upper frame and the lower frame is connected and fixed so as to be rotatable when receiving a knee load on the load receiving part ,
The lower frame extends in a direction perpendicular to the plate-like portion on the side surface of the plate-like portion in the vehicle width direction, and gradually decreases from the contact portion in contact with the vehicle body structure toward the rear of the vehicle body. A knee bolster structure having a side bracket provided . The upper frame is
The knee bolster structure according to claim 1, further comprising a vertical wall on a side surface in the vehicle width direction of the upper bent portion and the load receiving portion.