JP3757649B2 - Vehicle chassis frame collision safety structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention prevents the bolts for tightening the engine cross member bracket from being deformed due to deformation of the side member when an external force is applied during a collision or the like, and prevents shear breakage, thereby reducing the deformation of the side member and improving vehicle safety. The present invention relates to a vehicle chassis frame collision safety structure.
[0002]
[Prior art]
As shown in FIGS. 3 and 4, the chassis frame of the vehicle has a substantially U-shaped cross section and left and right side members 2, 2 arranged at appropriate intervals in the vehicle width direction, and cross members 3, 4 installed therebetween. And engine cross member structure 5 '. In particular, the engine cross member structure 5 ′ functions as a cross member and holds the engine 6. For example, as shown in FIG. 4, the engine cross member structure 5 ′ is arranged in the vicinity of the inflection portion 7 of the side member 2. The engine cross member structure 5 ′ includes an engine cross member bracket 8 fixed to the side member 2, an engine cross member 9 laid between the left and right engine cross member brackets 8, 8, and the like. The engine cross member bracket 8 is provided with an engine mount bracket 8a for supporting the engine.
[0003]
As shown in FIGS. 3 and 4, the engine cross member bracket 8 is fixed to the side member 2 with, for example, bolts. More specifically, the bolt is composed of two bolts 10 and 10a on the front side and two bolts 11 and 11a on the rear side, and these four bolts 10, 10a, 11, and 11a are used for engine crossing. The member bracket 8 is fixed to the side member 2. The bolts 10 and 10a on the front side are disposed in the vicinity of the inflection portion 7 and the bolt 10 is disposed substantially on the axis of the engine cross member 9.
[0004]
[Problems to be solved by the invention]
The engine cross member bracket 8 is firmly fastened to the side member 2 by the bolts 10, 10a, 11, and 11a, but the side member 2 is bent and deformed in the vehicle width direction when a large external force is applied during a collision or the like. Deformation of the side member 2 due to this force is suppressed by the engine cross member structure 5 ′, but a considerably large force acts on the bolts 10, 10 a, 11, 11 a, and in particular, it is substantially on the axis of the engine cross member 9. A large force acts on the bolt 10. On the other hand, since the inflection part 7 of the side member 2 has a small flatness, the contact state between the engine cross member bracket 8 and the side member 2 is not sufficient even if the bolts 10 and 10a on the front side are tightened considerably strongly. There is a possibility that a case may occur where a greater force than the bolts 11 and 11b is applied to the bolts 10 and 10a. If it is assumed that the bolt 10 is broken against an external force, the other bolts 10a, 11, 11a must bear the external force. Depending on the magnitude of the external force, the bolts 10a, 11, 11a are broken sequentially. As shown in FIG. 5, there is a possibility that the engine cross member bracket 8 on one side is detached from the side member 2. Furthermore, the engine cross member structure 5 ′ does not function as a cross member, and the amount of deformation of the side member 2 in the vehicle width direction becomes large, and there is a possibility that the living space of the cab may be narrowed.
[0005]
There are many known techniques related to the engine cross member structure for supporting the engine. For example, Japanese Utility Model Laid-Open No. 4-110616 is cited. This “engine rear mount structure” is a structure in which the engine is suspended by a relatively high rigidity engine mount member, and both ends of the engine mount member are fixed to the frame side member side by a high rigidity engine mount bracket. Although this fixing is based on bolts, a considerable tightening force is generated because the bolt mounting portion is flat. Therefore, in this structure, it is considered that the engine mount member is not easily detached from the frame side member side due to the loosening of the bolt when an external force is applied. However, even in this case, depending on the mounting position of the engine mount bracket, there is a possibility that the same result as in the above-described prior art may occur.
[0006]
The present invention has been invented in view of the above circumstances, and even when a large external force is applied, such as during a collision, the bolt does not drop off and break, and the engine cross member structure can be detached from the side member. An object of the present invention is to provide a vehicle chassis frame collision safety structure that is unlikely to occur and the engine cross member structure functions as a cross member, reduces side member deformation, secures a living space, and improves vehicle safety. And
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is fixed to the left and right side members 2 constituting a chassis frame of a vehicle, having a substantially U-shaped cross section and arranged at a predetermined interval in the vehicle width direction by bolts 10 or the like. It is applied to an engine cross member structure 5 including an engine cross member bracket 8 and an engine cross member 9 installed between the engine cross member brackets 8 to ensure the safety of the chassis frame when an external force is applied such as a collision. The vehicle cross frame safety structure for the engine cross member bracket 8 includes a bolt 10 disposed on the side of the side member 2 on the inflection portion 7 substantially on the axis of the engine cross member 9; Adjacent to the bolt 10, other bolts 10 a arranged on the flat part side other than the inflection part 7 of the side member 2 etc. A stopper pin 1 for fixing the engine cross member bracket 8 to the side member 2 is interposed between the bolts 10 and 10a. It is.
[0008]
The stopper pin bears an external force applied to the bolt by interposing the stopper pin between the bolt on the axis of the engine cross member and the adjacent bolt. Therefore, loosening of bolts, shear failure, etc. are prevented. Further, since the stopper pin is disposed on the substantially flat contact surface portion between the engine cross member bracket and the side member in the vicinity of the inflection portion, the stopper pin exhibits a strong locking force. Therefore, the effect which can fully prevent the shear fracture of a volt | bolt can be raised. According to the present invention, the deformation of the side member when an external force is applied can be reduced by a very simple means simply by providing a stopper pin.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of a vehicle chassis frame safety structure according to the present invention will be described in detail below with reference to the drawings. As shown in FIG. 1, in the present embodiment, a case will be described in which an engine cross member structure 5 according to the vehicle chassis frame collision safety structure of the present invention is disposed in the vicinity of the inflection portion 7 of the side member 2. Note that the present invention is similarly applied to flat portions other than the inflection portion 7 of the side member 2, but it is a matter of course that the inflection portion 7 can further improve the effect.
[0010]
As shown in FIGS. 1 and 2, the side member 2 has a substantially U-shaped cross section, and the closing plate 2a is welded to the inner surface of the side member 2 so as to have a sealed box-like cross section as a whole. Become. The engine cross member structure 5 of the present embodiment is disposed by being bolted to the lower surface of the side member 2 in the vicinity of the inflection portion 7 of the side member 2 having the above structure. In the inflection part 7, the side members 2 are connected by a gentle curve, and the area of the cross section gradually changes. The engine cross member structure 5 includes an engine cross member bracket 8 which is bolted to the lower surface of the side member 2 and an engine cross member 9 which is installed between the left and right engine cross member brackets 8 and 8.
[0011]
The engine cross member bracket 8 includes an attachment plate portion 8 b that is bolted in close contact with the lower surface of the side member 2 and an engine mount bracket 8 a that supports the engine 6. Note that both ends of the engine cross member 9 are fixed to the engine mount bracket 8a.
[0012]
As shown in FIGS. 1 and 2, the mounting plate portion 8b is fixed to the lower surface of the side member 2 by two bolts 10, 10a and bolts 11, 11a on the front side and the rear side, and the stopper pin 1 is mounted. It is done. In the present embodiment, the stopper pin 1 is disposed between the bolt 10 and the bolt 10a on the front side that are disposed substantially on the axis of the engine cross member 9. More specifically, since the portion where the bolt 10 is fastened substantially corresponds to the inflection portion 7, a slight gap is generated between the lower surface of the side member 2 and the mounting plate portion 8b. However, when the bolt 10 is tightened, the gap becomes almost zero. However, since the tightening force of the bolt 10 is partially used to eliminate the gap, the tightening strength of the mounting plate portion 8b at this portion is low. On the other hand, the portion to which the stopper pin 1 is attached is flattened by tightening at least the bolt 10, and by inserting the stopper pin 1 into this portion, the effect of sufficiently preventing the shear failure of the bolts 10 and 10 a can be exhibited. .
[0013]
When an external force is applied to the engine cross member structure 5 'having the conventional structure, a large force is particularly applied to the bolt 10 as described above. However, in the case of the engine cross member structure 5 of the present embodiment, the stopper pin 1 is provided in the vicinity of the bolt 10 and acts on the bolt 10 because the mounting plate portion 8b is firmly fixed to the lower surface of the side member 2. The force is supplemented by the stopper pin 1, and as a result, the bolt 10 is not loosened. If there is no slack of the bolt 10, the slack of the other bolts 10a, 11, 11a does not occur. Therefore, in this embodiment, the engine cross member structure 5 ′ as shown in FIG. 5 is not detached from the side member 2. As a result, the engine cross member structure 5 functions as a cross member, and the deformation of the side member 2 in the vehicle width direction is reduced. Thereby, the deformation of the entire chassis frame is also reduced, the reduction of the living space is prevented, and the safety of the vehicle can be ensured.
[0014]
In the above description, the engine cross member bracket 8 is fixed by the two bolts 10, 10a and 11, 11a on the front side and the rear side, but the present invention is not limited to this. Further, the mounting position, number, and shape of the stopper pin 1 are not limited to those described above or illustrated.
[0015]
【The invention's effect】
1) According to the vehicle chassis frame collision safety structure according to claim 1 of the present invention, an engine cross member bracket to be bolted is fixed to the side member by a stopper pin in addition to bolting, so that an external force is applied. The bolt is prevented from being broken due to the broken bolt from the side member of the engine cross member structure. Therefore, the engine cross member structure functions as a cross member to reduce the deformation of the chassis frame, prevent the reduction of the living space and ensure the safety of the vehicle. In particular, the stopper pin is almost on the axis of the engine cross member, and the force applied to the bolt is supplemented by the stopper pin by arranging the stopper pin between the bolt arranged at the inflection part and the adjacent bolt, so that the inflection Even if there is a slight gap between the part and the engine cross member, the bolt tightening force and the supplement by the stopper pin prevent the bolt from falling off or being destroyed, thereby ensuring safety.
[Brief description of the drawings]
FIG. 1 is a side view showing a detailed structure of a vehicle chassis collision safety structure according to the present invention.
FIG. 2 is a top view of FIG.
FIG. 3 is a plan view showing a mounting structure of a conventional engine cross member structure.
4 is a side view of FIG. 3;
FIG. 5 is a schematic view showing a state of deformation of a conventional chassis frame when an external force is applied and a state of detachment from a side member of an engine cross member structure associated therewith.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Stopper pin 2 Side member 2a Closing plate 3 Cross member 4 Cross member 5 Engine cross member structure 6 Engine 7 Bending part 8 Engine cross member bracket 8a Engine mount bracket 8b Mounting plate part 9 Engine cross member 10 Bolt 10a Bolt 11 Bolt 11a bolt

Claims (1)

An engine cross member bracket (8) which constitutes a chassis frame of the vehicle and has a substantially U-shaped cross section and is fixed to the left and right side members (2) which are arranged at predetermined intervals in the vehicle width direction by bolts (10 etc.) ; Applied to an engine cross member structure (5) having an engine cross member (9) installed between the engine cross member brackets (8) to ensure the safety of the chassis frame when an external force is applied such as in a collision. The engine cross member bracket (8) is arranged on the side of the inflection part (7) of the side member (2) substantially on the axis of the engine cross member (9). and setting by a bolt (10), the other arranged in the curved portion (7) flat portion side other than the side members adjacent (2) into the bolt (10) Bolts by (10a, etc.) is fixed to the side member (2), stopper the flat portion side between the bolt (10, 10a) is secured to the engine side member cross member bracket (8) (2) side A vehicle chassis frame collision safety structure, characterized in that a pin (1) is interposed.

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