JPH09309394A - Knee bolster holding structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the position change of a knee bolster at the time of large impact load acting from the front by fitting the knee bolster to an upper holder bracket and a lower holder bracket fitted to the vertically spaced positions of a body, and forming the upper holder bracket into more easily deformed shape than the lower holder bracket. SOLUTION: A knee bolster 19 arranged in a position in front of the knees of an occupant sitting on a seat is formed of a plate 20 facing the seat side, and a bolster bracket of shape vertically bent at an intermediate part and easily deformed in a longitudinal direction. This knee boslter 19 is fitted to a holder bracket 23 formed of an upper panel and upper and lower holder brackets 24, 25. In this case, in order to form the upper holder bracket 24 into such shape as to be more easily deformed receiving longitudinal impact load than the lower holder bracket 25, a cutout 24e is provided at a flange 24d of the upper holder bracket 24, and an arm part of the upper bracket 24 is formed by alternately repeating straight parts 24b and bent parts 24c.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for holding a knee bolster, and more particularly to a structure for mounting a knee bolster on a vehicle body, which a knee of a vehicle occupant contacts.

[0002]

2. Description of the Related Art Seat belts, airbags and the like are well known as a device for preventing the posture of an occupant from being collapsed when a large impact load is applied from the front of an automobile. When a large impact load is applied to the vehicle from the front, the vehicle is rapidly decelerated, and the occupant sitting in the driver's seat or the passenger seat is pushed forward by inertia. The knee bolster prevents the lower limbs of the occupant from jumping forward, and the knees of the occupant, which has started to be pushed forward due to inertia,
Can be supported while buffering. The upper body of the occupant can be supported by using other devices such as an airbag and a seat belt together.

FIG. 4 is a side view showing a conventional knee bolster, in which the knee bolster 2 is provided above and in front of the front end of the seat 1 seating surface.
Is arranged. In front of the steering wheel 3, there is a frame member 4 fixed to the left and right of the vehicle body. The frame member 4 supports the knee bolster 2 via an arm member 5 and a steering shaft connected to the steering wheel 3. 6 is supported via a bracket 7.

In general, the interior of an automobile is surrounded by left and right side panels or doors, an upper roof and a lower floor panel on four sides of the peripheral surface, and the front is covered with a dash panel and a windshield. There is. When a large impact load is applied from the front of the car, the amount of deformation is small because the stress is dispersed by the door, side panel, roof, and floor panel in the part close to the cabin surface,
The central portion of the front of the passenger compartment, that is, the upper portion of the dash panel, has a large amount of deformation because there are few members that support the load. In addition, in a vehicle having an engine hood in the front of the passenger compartment, the load from the front is transmitted to the upper portion of the dash panel via the engine hood, so that the amount of deformation of the upper portion of the dash panel is further increased.

When a large impact load is applied from the front of the vehicle, the area from the front end of the vehicle to the front of the seat 1 is deformed. At this time, since the frame member 4 is close to the upper part of the dash panel, it may be deformed at the same time as the front part of the vehicle body. Further, the position of the knee bolster 2 attached to the frame member 4 via the arm member 5 is also displaced. At the same time that the vehicle body is rapidly deformed, a large deceleration is applied to the passenger compartment, the occupant moves forward due to inertia, and the knee of the occupant abuts on the knee bolster 2. Therefore, when the frame member 4 is deformed, the position of the knee bolster 2 has already changed when the knee of the occupant contacts the knee bolster 2, and when the knee bolster 2 is extremely deformed,
The buffer performance as designed cannot be obtained.

Further, since the knee bolster 2 changes to various positions only by slightly varying the magnitude and direction of the impact load acting from the front, it is difficult to always support the lower limbs of the occupant from the front. When the position of the knee bolster 2 is changed, when the knees of the occupant come into contact with the knee bolster 2,
The upper body may come off from the front due to the position of. For devices such as airbags and seat belts,
High performance that can withstand such a posture change of the occupant is required, and an expensive device must be adopted.

[0007]

SUMMARY OF THE INVENTION The present invention provides a mounting structure in which the position of the knee bolster does not change even when a large impact load is applied from the front of the vehicle.

[0008]

In order to achieve the above object, in the present invention, a knee bolster is arranged in front of and above the seating surface tip of the seat provided in the vehicle compartment, and the upper holder bracket and the lower holder bracket are connected to each other. The knee bolsters are attached to the upper holder bracket and the lower holder bracket while being mounted at positions separated from each other vertically on the vehicle body.
The upper holder bracket has a shape that is more easily deformed than the lower holder bracket with respect to the longitudinal load.

[0009]

1 to 3 show an embodiment of the present invention, and FIG. 1 is a sectional view showing a front portion of a passenger compartment of an automobile.
FIG. 2 is a perspective view of the knee bolster and bracket,
FIG. 3 is a partial side sectional view of the same component.

The passenger compartment C is vertically surrounded by a roof 8 and a floor panel 9, and is also right and left surrounded by left and right doors (not shown) and side panels in front of the door. The front of the passenger compartment C is covered with a windshield 10 and a dash panel 11, and the lower end of the dash panel 11 is welded to the floor panel 9. A cowling having a box-shaped cross section including a top panel 12, an upper panel 13, and a front panel 14 is welded to the upper portion of the dash panel 11 to connect the left and right sides of the vehicle body. The floor panel 9 and the dash panel 11 are formed with tunnel portions 9a and 11a projecting into the vehicle interior C.
A transmission, a gear shift operation link, a parking brake transmission wire, and the like, which are not shown, are attached to the insides of a and 11a. On the floor panel 9, via the rail 15,
A seat 16 whose front and rear positions can be adjusted is attached. The seat 16 shown in FIG. 1 is a seat located in the front row among the seats arranged in front and rear in the vehicle interior C. An instrument panel 17 covering instruments is attached to the top panel 12, and a steering wheel 18 for steering front wheels is provided behind the instrument panel.
Is arranged.

A knee bolster 19 is arranged in front of and above the seat surface tip 16a of the seat 16. The knee bolster 19 is arranged at a position in front of the occupant's knee when the occupant sits on the seat 16. Knee bolster 1
9 is formed of a plate 20 facing the seat 16 side and a bolster bracket 21 having a U-shaped cross section that opens rearward. Both rear ends of the bolster bracket 21 are welded to the plate 20, and an intermediate portion is bent upward and downward so that the bolster bracket 21 is easily deformed in the front-rear direction. The reinforcement 22 is welded near the tip of the bolster bracket 21 to prevent stress from concentrating on the tip of the bolster bracket 21.

A holder bracket 23 is attached between the upper panel 13 and the lower part of the vehicle body. The holder bracket 23 is a dash panel 11 having a wide surface.
By connecting the lower part of the vehicle body to the upper panel 13, the dash panel 11 and the floor panel 9 are prevented from vibrating during traveling, and the knee bolster 19 is used as a bracket for mounting on the vehicle body. The holder bracket 23 is assembled by welding an upper holder bracket 24 and a lower holder bracket 25. Furthermore, the lower holder bracket 25 is assembled by welding a mounting bracket 27, 28 extending downward from both ends of the member 26 to a member 26 extending in the lateral direction. The holder bracket 23 is an upper bracket 24.
, The one mounting bracket 27 and the other mounting bracket 28 are respectively attached to the upper panel 13,
The tunnel portion 11a of the dash panel 11 and a side panel (not shown) in front of the door are fixed by bolts. The member 26 is arranged at a position below which a sufficient space for the occupant's feet is secured. Although the upper end of the upper bracket 24 is attached to the upper panel 13 in this embodiment, it may be attached to the dash panel 11.

The upper holder bracket 24 is formed by press-forming a steel plate, and is provided with a pair of arm portions 24a, 24a which are bifurcated downward from the upper end. Each arm portion 24a, 24a has a knee bolster 19
And the upper holder bracket 24 is deviated from a straight line connecting the vehicle body side mounting portion at the upper end to form a detour.
The curve b and the bent portion 24c are alternately repeated to curve downward from the rear. In addition, each arm portion 24a, 2
4a is integrally provided with flanges 24d and 24d bent substantially at right angles, and the cross section thereof has an L shape or a square shape that opens upward. A notch 24e is provided at a position corresponding to the bent portion 24c of the flanges 24d, 24d. The upper holder bracket 24 is provided with a bolt hole and a welding nut 24f near its lower end. A hook 24g is integrally cut and raised from the arm portion 24a near the welding nut 24f. The knee bolster bracket 21 has a bolt hole 21a and an engagement hole 21b.
Corresponding to the welding nut 24f and the hook 24g of the upper holder bracket 24. To attach the knee bolster 19 to the holder bracket 23, the engaging hole 21b is engaged with the hook 24g, and the bolt 29 is screwed into the welding nut 24f from the direction of the knee bolster 19.

In the vehicle of this embodiment, the left and right doors (not shown) or side panels located in front of the doors, the roof 8 and the floor panel 9 allow the left and right and upper and lower sides of the passenger compartment to be different from each other. being surrounded. The front of the passenger compartment is covered with a dash panel 11, a cowling, and a windshield 10. When a large impact load is applied from the front of the vehicle, the front part of the vehicle body is deformed and the dash panel 11 is also deformed. In the peripheral portion of the dash panel 11, the load is distributed to the door, the side panel, and the floor panel 9, so that the applied stress is small and the amount of deformation is small. Compared to this, the upper part of the dash panel 11 is
It is supported only by the cowling. The cowling is connected to the left and right side panels, but the longitudinal direction of the cowling is orthogonal to the direction of the load, so the load from the front cannot escape to the side panels. Therefore, also in the automobile of this embodiment, the upper portion of the dash panel 11 tends to have a larger deformation amount than the lower portion, as in the conventional vehicle.

In the vehicle of this embodiment, the knee bolster 19 is attached to the vehicle body by the upper holder bracket 24 and the lower holder bracket 25. Further, the strength of the upper holder bracket 24 in the front-rear direction, that is, the impact resistance when an impact load is applied from the front is made smaller than that of the lower holder bracket 25. When an impact load is applied from the front of the vehicle, the upper holder bracket 24 is largely deformed, but the lower holder bracket 25 is hardly deformed. Therefore, even after receiving a large impact load from the front, the knee bolster 19 is supported by the lower holder bracket and its position hardly changes.

In this embodiment, the upper holder bracket 2
In order to make 4 more deformable than the lower holder bracket 25 against an impact load in the front-rear direction, the flange 24d of the upper holder bracket 24 is provided with a notch 24e, and the arm portion 24a of the upper bracket 24 is The straight line portions 24b and the bent portions 24c are alternately and repeatedly formed. By providing the cutout 24e in the flange 24d, the cross-sectional area and the cross-section coefficient of the portion where the cutout is provided are smaller than those of the other portions, and the stress is concentrated and the front-back direction is easily deformed. In addition, the arm portion 24a is connected to the linear portion 2
4b and the bent portion 24c are repeatedly formed, the stress acting on the arm portion 24a is reduced by the bent portion 24c.
Therefore, only the bent portion 24c can be deformed. In the embodiment, the notch 24e and the bent portion 24c are formed at substantially the same position, so that the portion is more easily deformed than the other portions with respect to the impact load in the front-rear direction.

When the upper holder bracket 24 is provided with a partial stress concentrating portion, such as the above-mentioned notch 24e and bent portion 24c, it is desirable to provide two or more stress concentrating portions. When there is only one stress concentration portion, the vehicle body side attachment portion of the upper end of the upper holder bracket 24 and the knee bolster 19 are deformed vertically or horizontally at the same time due to the deformation in the front-rear direction, and cannot be freely deformed. . If there are two or more stress concentration parts, the upper holder bracket 2
The deformation of No. 4 in the front-back direction is easily absorbed by the deformation of the stress concentration portion, and does not affect the knee bolster 19.

[0018]

According to the present invention, the upper holder bracket 24 is not deformed and does not affect the mounting position of the knee bolster 19 even when a large impact load is applied from the front of the automobile to the extent that the vehicle body is deformed. . Further, since the knee bolster 19 can accurately support the occupant's knees even with an impact load from the front, the knee bolster 19 can sufficiently exhibit the cushioning performance assumed at the time of design. Furthermore, since the knee of the occupant abuts on the knee bolster 19 from the front, it is not necessary to widen the protection range of other occupant holding devices such as airbags and seat belts, and an inexpensive device can be adopted. Further, during normal traveling, the holder bracket 23
Can suppress the vibration of the lower part of the vehicle body such as the dash panel 11 and improve the comfortability.

[Brief description of drawings]

FIG. 1 is a sectional view showing a front portion of a vehicle compartment of an automobile to which the present invention is applied.

FIG. 2 is a perspective view of a knee bolster and a bracket.

FIG. 3 is a side view including a partial cross section of a knee bolster and a bracket.

FIG. 4 is a side view showing a conventional knee bolster.

[Explanation of symbols]

 C vehicle compartment 16 seat 16a seat tip 19 knee bolster 23 holder bracket 24 upper holder bracket 24b straight portion 24c curved portion 24e notch 25 lower holder bracket

Claims (4)

[Claims] 1. A knee bolster is arranged in front of and above a seating surface tip of a seat provided in a vehicle compartment, and the upper holder bracket and the lower holder bracket are mounted at positions vertically separated from each other, and the upper holder bracket is mounted. A holding structure for a knee bolster, wherein the knee bolster is attached to the lower holder bracket, and the upper holder bracket is more easily deformed than the lower holder bracket with respect to the load in the front-rear direction. 2. The holding structure for a knee bolster according to claim 1, wherein the upper bracket is provided with at least one notch. 3. The holding structure for a knee bolster according to claim 1, wherein the upper bracket has a shape detouring a straight line connecting the knee bolster and the vehicle body side mounting portion. 4. The holding structure for a knee bolster according to claim 3, wherein the upper bracket comprises a plurality of straight portions and curved portions.