JPH10147255A - Vehicle and its reinforce - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrict any increase in deformation quantity by quickly increasing again a frame resistant force dropped down to 1/3 to 1/5 of its maximum value only when it is required to absorb a more quantity of energy by the frame than expected at high speed collision. SOLUTION: A reinforce is in such a construction as reinforcing the kick-up part of a frame so s to absorb impact and consisting of a main frame of a closed sectional area extended in the longitudinal direction of a vehicle, the kick-up part 2 of the main frame and a reinforce 3 arranged along the inside of the kick-up part 2 of the main frame. Furthermore, a space part C is formed by the inside bottom surface of the main frame and the bottom surface of the reinforce 3 and also an U-shape groove 3c is provided in a port position facing the bent part 2a of the kick-up part 2 on the upper surface of the reinforce 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle having a frame such as a passenger car or a truck, a vehicle such as a monocoque body type vehicle, and a reinforce used for the vehicle. Protection is an issue.

[0002]

2. Description of the Related Art Generally, in a vehicle with a frame as shown in FIGS. 2 and 3, most of the collision energy is absorbed by deformation of the frame during a collision. Therefore, the vehicle body characteristics at the time of the collision, that is, the time history of the deceleration due to the collision, the cabin deformation amount, and the like are determined by the deformation resistance of the frame. That is, in a conventional vehicle with a frame, the breaking force at the time of a collision (see FIG. 4) is controlled by the cross-sectional shape, plate thickness, reinforcement of the frame, and the like. The reinforce is generally fixed inside the frame by welding or the like, and the energy of the collision applies stress not only to the entire vehicle but also to the frame, and at the same time stress is generated in the reinforce (see FIGS. 5 and 6). As a result, as shown in FIG. 7, the reinforcement is greatly deformed at the kick-up portion.

[0003]

In such a conventional technique, the degree of protection of the occupant in the event of a collision depends on the time history of the deceleration occurring in the cabin (hereinafter abbreviated as "cab G") and the deformation of the cabin. It depends greatly on the amount. That is, for the former, by keeping this average low, the impact received by the occupant via restraint means such as a seat belt is reduced, and for the latter, if the occupant is too large, the occupant enters the cabin due to the inertial movement of the passenger. The degree of collision of the occupant increases, which causes problems such as difficulty in escaping and rescuing the occupant. If the deformation resistance is lowered to lower the cab G, the energy absorption effect of the frame is reduced and the amount of deformation of the passenger compartment is increased, so it is difficult to balance both.

[0004] In a frame deformation mode in a frontal collision of a vehicle with a frame, bending deformation generally occurs without rearward crushing. However, as shown in FIG. 6, a drag characteristic (FS characteristic) of the bending mode. ) Shows the highest value at the beginning of the displacement, and then decreases rapidly as the displacement increases, and the drag becomes 1/3 to 1/5 of the highest value. .

When a reinforcement is installed inside the frame in order to improve the energy absorption effect in the latter half of the folding, the FS characteristics of the FS characteristic including the initial maximum value increase as a whole, but the deformation of the frame is increased. In some cases, the drag balance of the portion may be lost and the cab G characteristic may be changed.

Therefore, in order to build a vehicle body with good occupant protection in a limited crash zone, it is designed to keep the cab G low by maximizing the crash zone under a certain collision condition. In this case, in the case of a collision in which reframe deformation increases due to the collision conditions assumed at the time of design, for example, in a case of high speed, heavy weight, one-sided collision, etc., the remaining energy must be absorbed by a frame with a greatly reduced drag, and the passenger compartment deformation. There was a problem that the amount increased remarkably (see FIG. 5).

In connection with these problems, Japanese Patent Laid-Open No.
The sub-frame described in Japanese Patent No. 2254 has a notch formed slightly behind the position facing the kick-up portion of the main frame, and the sub-frame has a square-shaped surface end, so that the front end of the sub-frame at the time of collision can be used. There is disclosed a technology in which an impact force absorbing structure is formed in which a portion abuts and locks on a kick-up portion, a notch formed in a subframe matches the notch, and the frame is easily bent without being stretched. . However, in this structure, the notch does not always match with the collision mode, and it is considered that the function is not reliably performed. Especially, since the cross member has a closed cross section, if the main frame and the sub frame are penetrated by bolts at both ends, the sub frame cannot move instantaneously in the main frame at the time of collision, It is hard to say that this prior example is a right to directly protect the kick-up part.

Further, the technique described in Japanese Patent Application Laid-Open No. 5-15952 discloses a technique in which a cab stopper is disposed in this kick-up portion, so that the relative movement amount of the frame increases and the cabin deformation amount increases. There is. The present invention has been made in view of the situation of the prior art described above, and the subject thereof is that, in a collision of a vehicle with a frame or the like, only when the frame must absorb more energy than expected, the highest value is obtained. An object of the present invention is to sharply increase the frame drag reduced to 1/3 to 1/5 again to improve the energy absorption effect and suppress the increase in the amount of deformation.

[0009]

According to a first aspect of the present invention, there is provided a vehicle having a kick-up portion provided in a closed cross section and a kick-up portion of the frame. And a space between the upper surface or lower surface of the vehicle outside the bent portion of the kick-up portion and the surface of the reinforce corresponding to the surface, and the bent portion of the kick-up portion in the reinforce. When a collision load is applied to the kick-up portion of the frame, the frame exerts resistance to the primary impact force, and the reinforcement force is applied to the impact force beyond that when a collision load is applied to the kick-up portion of the frame. It is characterized by absorbing much of the impact force.

According to a second aspect of the present invention, in addition to the first aspect, the reinforce is disposed along the inside of the kick-up portion of the frame, and the reinforce is disposed outside the vehicle from the bent portion of the kick-up portion of the frame. By forming a space between the inner lower surface and the bottom of the reinforce corresponding to the inner lower surface, a resistance is exerted against a primary impact force. It is characterized in that the concave portion provided on the upper surface and the kick-up portion are directly matched to absorb the impact force.

The vehicle according to claim 3 is the vehicle according to claim 1 or 2.
In addition to the means described above, the main frame extends in the front-rear direction of the vehicle, and the bottom of the reinforcement is inclined with respect to the inner and lower surfaces in front of the vehicle from the bent portion of the kick-up portion of the main frame to form a space. By doing so, the most frequent frontal impact is reduced.

A vehicle according to a fourth aspect of the present invention has a structure in which a kick-up portion of the frame is reinforced to absorb a shock, wherein the main frame has a closed cross section extending in the front-rear direction of the vehicle, and a kick-up portion of the main frame. And a reinforce provided along the inside of the kick-up portion of the main frame, and a space is formed by an inner bottom surface of the main frame and an inclined surface formed by bending the lower surface of the reinforce. In addition, by providing a U-shaped groove in a portion of the upper surface of the reinforce facing the bent portion of the kick-up portion, when a collision load is applied to the kick-up portion of the main frame, the main frame is not affected by the primary impact force. In the above, the drag is exerted, and for a further impact, the rain force absorbs most of the impact in a stepwise manner.

According to a fifth aspect of the invention, there is provided a reinforcement for a vehicle, wherein a vertical section of a rear portion is formed in a U-shape, and a lower surface on a front side is a curved inclined surface having an angle larger than a lower surface inclination angle of a kick-up portion of a vehicle frame. By forming and forming a U-shaped groove at a position facing the bent portion of the upper surface of the reinforce, most of the impact force can be absorbed stepwise.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. 1 and FIGS. (Outline of Embodiment) In this embodiment, when a vehicle collides, a reinforcement 3 is provided inside or outside a kick-up section 2 for absorbing the collision energy by bending a frame 1 of the vehicle. A space C is formed between a portion of the frame 1 and the kick-up portion 2 of the frame 1 so that the frame 1 operates only when the frame 1 is bent more than an expected amount. That is, the reinforce 3 enhances the bending resistance of the frame 1 by suppressing the change in the cross-sectional shape due to the bending of the kick-up portion 2 in addition to the resistance generated at the time of its own plastic deformation.

(Specific Configuration of the Embodiment) (Configuration of Vehicle Body) The overall structure and frame structure of the vehicle body are basically the same as those of the conventional structure as shown in FIGS. This indicates that the present invention can be easily applied to a conventional vehicle. That is, as shown in FIG. 1 and FIG.
A steel U-shaped frame is fitted to form a closed cross section, and the front portion is bent to form a kick-up portion 2.

The kick-up portion 2 of the main frame 4 is, as shown in FIGS.
When the vehicle is viewed from the side of the vehicle body, the main frame 4 where the front wheels and the front pillars are disposed is higher than the ground height of the main frame 4 where the doors and center pillars of the passenger compartment are disposed. It refers to the part that is bent upward to increase the ground clearance. This is the main frame 4
Is a frame structure necessary for support, and this bent portion is referred to as a kick-up portion 2 of the main frame 4. When an impact force is applied to the frame 1 from the front, the main frame 4 contracts and tries to absorb the impact force. At this time, as shown in FIG. 4, the kick-up portion 2 is more greatly deformed. In this embodiment, the kick-up section 2 is provided with a reinforcement 3.

(Reinforce 3 Shape) As shown in FIG. 8, the rear body 3a is formed in a U-shape in a vertical cross section, and the entire shape of the reinforce 3 is a boat shape in a side view. It is formed. That is, the front bottom 3b is formed to be curved upward, and a groove-shaped recess 3c is formed near the upper front thereof. The main body portion 3a behind the concave portion 3c is formed in substantially the same shape as the inner shape of the main frame 4. The reinforcement 3 is fitted and disposed inside the kick-up portion 2, and has a space between the inner lower surface on the vehicle outside and the lower side of the reinforcement 3 from the position of the bent portion 2 a of the kick-up portion 2 of the frame 1. C is formed.

Then, the frame 1 is used for the primary impact force.
With respect to an impact force larger than that, the concave portion 3c provided on the upper surface of the reinforce 3 and the bent portion 2a of the kick-up portion 2 are directly matched to absorb the impact force. The curved shape of the front bottom 3b is derived from various conditions, and a method of deriving the curved shape will be described (see FIG. 9).

First, a deformation mode at the time of collision of the kick-up unit 2 without the reinforcement 3 is shown in FIG. Here, the amount of deformation of the main frame 4 is replaced with the change in the angle of the main frame 4 as follows. theta _0: upward angle theta ₃₀ of the collision before the kick-up portion 2: 30 km / maximum angle of bending caused by frontal collisions at h theta _35: 35km / maximum angle of bending caused by a head-on collision in h of this theta ₀ and theta ₃₀ FIG.
As shown in (1), the shape of the portion A where both main frames 4, 4 'overlap each other is determined. Based on the shape of the overlapping portion A, the shape, thickness, etc. of the reinforcement 3 are determined in consideration of the desired drag characteristics and productivity. The points to be considered at that time are described below.

1. Since the portion pointed by the arrow shown in FIG. 11 is important for quickly raising the drag, the shape obtained by overwriting should be kept as faithfully as possible. Among the arrows, the arrow α acting on the concave portion 3c serves to suppress the change in cross-sectional shape, and the arrow β acting on the curved portion of the bottom 3b on the front lower surface serves to transmit the drag of the reinforce 3 itself to the main frame 4.

2. To not give an influence on the cab G characteristic up theta _30, the fixed portion 5 of the main frame 4 inside the reinforcement 3 performed by welding or the like only to the extent of backward does not extend deformation noticeable even after deformation. As can be seen from the above description, the present invention is a structure of the rain force 3 which can be applied to the main frame 4 without special work.
This is a structure that absorbs excessive collision energy applied to the kick-up unit 2.

(Effects of the embodiment) When this embodiment is not adopted, when a running vehicle is crushed using a majority of the crash zone due to a frontal collision at 30 km / h against a fixed wall, the front of the vehicle is assumed. Assuming that the F-δ characteristic of FIG. 12 is the one shown in FIG. 12, the increase B in the collision speed to 35 km / h
Has a maximum frame deformation of ₃₀ km / h S ₃₀
The deformation is absorbed by the subsequent deformation, and the deformation amount of the main frame 4 is greatly increased, so that the cabin deformation is excessive.

[0023] However, the configuration of the present embodiment increases the drag of S ₃₀ and later, the main frame 4 deformation amount reinforcement 3 absorbs the energy increment B 'does not increase significantly. Therefore, there is little room deformation. Also, S ₃₀
At the point of time, when the deformation phenomenon of the main frame 4 in progress is the downward bending of the kick-up portion 2, the reinforce 3 having the shape derived by the above-described method is provided inside the kick-up portion 2, increased drag of S ₃₀ or later, can be absorbed Engineering energy of rate increase B in lesser stroke S _'35.

The collision Engineering energy amount proportional to the square of the velocity, because the increase rate = 35 ^{2/30 2} = 1.36 collision Engineering energy increasing rate becomes 36%. According to the above embodiment, the front end of the reinforce 3 is formed in a boat shape, and the front end receives an impact force and rebounds itself by a drag generated at the time of plastic deformation.

A U-shaped groove 3c is formed on the upper surface of the reinforcement 3, and the U-shaped groove 3c is located at a position just opposite to the bent portion 2a of the kick-up portion 2 of the main frame 4, that is, the kick-up portion 2 Groove 3 just below the bend 2a
By placing c, the bent portion 2a directly fits into the groove 3c at the time of collision, and the reinforce 3 reliably catches the kick-up portion 2 and suppresses a change in cross-sectional shape.

(Effects of the Embodiment) As described above, the present embodiment has a structure capable of absorbing energy stepwise in any collision mode while utilizing the characteristics of the main frame 4 provided with the reinforce 3. I have. Moreover, the structure is inexpensive, lightweight, easy to mount, and as a result, the protection of the occupant in the cappin is reliably improved. In addition, there is an advantage that a predetermined rigidity can be maintained against a torsional load or a bending load acting on the main frame 4 during normal running.
In other words, the cab G
Without changing the characteristics, the progress of deformation can be suppressed rapidly (can be moderate depending on the setting of the reinforce 3) in a region (35 km / h or more in the embodiment) larger than the target deformation amount. This makes it very easy to balance the cab G and the passenger compartment deformation.

The shape of the reinforce 3 can be easily obtained by referring to a frame deformation state in a collision experiment or a collision simulation showing a limit deformation in which priority is given to relaxation of the cab G. For example, by performing the experiments of Cases 1 to 3 under the following conditions A and B, the data can be used as basic data in the rainforce design.

(Examples of experimental conditions) Collision conditions that cause excessive deformation of the cabin Condition A Condition B Case 1 Increase in collision speed 30 km / h ⇒ 35 km / h Case 2 Increase in vehicle weight Empty collision ⇒ Load collision Case 3 Unbalanced In these cases, the provision of the reinforcement 3 in consideration of the amount of frame deformation under the collision condition A provides the condition B
In this case, the rate of increase in room deformation can be suppressed. Also,
The reinforce 3 of the embodiment increases the bending resistance of the main frame 4 by suppressing the change in the cross-sectional shape due to the bending of the frame, in addition to the resistance generated at the time of its own plastic deformation, and is therefore more efficient than the conventional reinforce. Further, the thickness of the reinforce 3 and the main frame 4 can be reduced as compared with the conventional one, so that weight reduction and cost reduction can be expected. Further, according to this structure, the cost, weight, assembly man-hour, and workability can be improved.

(Other Embodiments) As described in the embodiments, the present invention is an invention for reducing an increase in the deformation amount under a collision condition in which the cabin deformation amount is excessive. Conceivable. The reinforce of the present invention is not limited to a vehicle with a frame, but can be applied to all vehicles (eg, a monocoque body) in which a basic structural member is bent during a collision to thereby absorb energy. Further, the present invention can be applied not only to the frontal collision but also to other collision modes such as a rear and side collision. In the above-described embodiment, the reinforce 3 is mounted inside the main frame 4 having a closed cross section. However, the reinforce 3 may be provided outside the main frame 4 or a further reinforce (shown in FIG. ) May be arranged. Also, a rain force may be provided inside and outside the kick-up unit 2.

The above description relates to a reinforce applied to a kick-up portion in which the frame is bent in a vertical direction when viewed from the side of the vehicle. Some frames have a frame. The present invention can also be applied to the reinforce of a frame that bends horizontally on such a plane.

[0031]

As described above, the present invention has the following effects. 1. According to the first aspect of the present invention, when a collision load is applied to the kick-up portion of the frame, the frame exerts a resistance against the primary impact force, and the impact force is applied to the reinforce for the impact force exceeding the primary impact force. The absorption makes it easier to balance the time history of the deceleration occurring in the cabin and the amount of deformation of the cabin, thereby facilitating the safety design of the traveling vehicle. Further, since the energy of the collision can be absorbed step by step, the protection of the occupant at the time of the collision can be improved, and at the same time, it is inexpensive, lightweight and easy to mount. Then, during normal running, predetermined rigidity can be maintained against a torsional load or a bending load acting on the frame. Further, according to this structure, the cost, weight, assembly man-hour, and workability can be improved.

2. According to the second aspect of the present invention, in addition to the effect of the first aspect of the present invention, by providing the reinforce inside the frame, the structure of the frame is made compact, and the drag of the reinforce is applied to the frame. I can tell you enough. 3. According to the third aspect of the present invention, in addition to the effects of the first or second aspect, the frame is extended in the front-rear direction of the vehicle, and the inner and lower surfaces of the kick-up portion of the frame are located forward of the vehicle. By forming the space portion by inclining the lower surface of the reinforce, the most frequent frontal impact is reduced, which contributes to further improvement of the safety of the traveling vehicle.

4. According to the invention described in claim 4, when a collision load acts on the kick-up portion of the main frame,
The main frame exerts resistance to primary impact, and more force can be absorbed more gently by the rainforce for greater impact, contributing to improved protection of occupants during collisions I do. 5. According to the fifth aspect of the present invention, it is possible to provide a reinforce capable of gently absorbing an impact force, and it can be easily mounted on a frame and versatility can be expected.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention and is a partial perspective view of a main part thereof.

FIG. 2 is a schematic side view of a vehicle to which the embodiment is applied.

FIG. 3 is a perspective view of a frame to which the embodiment is applied.

FIG. 4 is a side view at the time of a collision of the vehicle to which the embodiment is applied;
(A) shows a time of 30 km / h, and (B) shows a time of 35 km / h.

FIG. 5 is a correlation diagram showing the relationship between the displacement of the vehicle body and the drag of the entire vehicle body at the time of the collision.

FIG. 6 is a correlation diagram showing a drag characteristic (FS characteristic) of a breaking mode occurrence portion at the time of the collision.

FIG. 7 is a modified explanatory diagram showing a state before (A) and after (B) collision of a frame at the time of a collision in a conventional technique.

FIG. 8 is an exploded perspective view of a main part of the embodiment.

FIG. 9 is an explanatory diagram for obtaining a basic shape of the reinforce of the embodiment.

FIG. 10 is a layout diagram of the reinforce of the embodiment, showing a state of attachment (A) and a state of collision (B).

FIG. 11 is an operation diagram of the reinforce in FIG.

FIG. 12 is a conceptual diagram of energy absorption characteristics of the entire vehicle at the time of a collision in the embodiment.

FIG. 13 is a conceptual diagram of an energy absorption characteristic of a kick-up portion at the time of a collision in the embodiment.

[Explanation of symbols]

 Reference Signs List 1 frame 2 kick-up part 2a bent part 3 reinforcement 3a main body part 3b bottom part 3c concave part (U-shaped groove) 4 main frame 5 fixing (welding) part A overlapping part B increased amount C space part

Claims (7)

[Claims] 1. A frame provided with a kick-up portion having a closed cross section, and a reinforce disposed along the kick-up portion of the frame, wherein the upper surface of the kick-up portion on the outer side of the vehicle with respect to a bent portion or A vehicle, wherein a space is formed between a lower surface and a surface of a reinforce corresponding to the lower surface, and a concave portion is formed in a portion of the reinforce facing the bent portion of the kick-up portion. 2. A reinforcement according to claim 1, wherein the reinforcement is disposed along the inside of the kick-up portion of the frame, and the inner lower surface of the vehicle outer portion and the bottom of the reinforce corresponding to the inner lower surface from the bent portion of the kick-up portion of the frame. 2. The vehicle according to claim 1, wherein a space is formed between the vehicles. 3. A space portion is formed by extending a main frame in the front-rear direction of the vehicle, and inclining a bottom portion of the reinforce with respect to an inner lower surface in front of the vehicle from a bent portion of a kick-up portion of the main frame. Claim 1 characterized by the following:
Or the vehicle according to 2. 4. A structure for reinforcing a kick-up portion of a frame and absorbing a shock, the main frame having a closed cross section extending in the front-rear direction of the vehicle, a kick-up portion of the main frame, A reinforcement is provided along the inside of the kick-up portion, and a space is formed by an inner bottom surface of the main frame and an inclined surface formed by being curved on a lower surface of the reinforcement,
A vehicle, wherein a U-shaped groove is provided in a portion of the upper surface of the reinforce facing the bent portion of the kick-up portion. 5. The vehicle according to claim 1, wherein the kick-up portion of the frame bends in a horizontal direction when the vehicle is viewed two-dimensionally. 6. A vertical section of a rear portion is formed in a U-shape, a lower surface on a front side is formed as a curved inclined surface having an angle larger than a lower surface inclination angle of a kick-up portion of a vehicle frame, and the upper surface of the reinforce is bent. U at the position facing the part
Reinforcement for vehicles characterized by having a shape groove. 7. The vehicle reinforce according to claim 6, wherein the kick-up portion of the vehicle frame is bent in a horizontal direction when the vehicle is viewed in a plan view.