JP5074668B2 - Engine support structure - Google Patents

Description

  The present invention relates to a support structure that supports an engine, and more particularly, to an engine support structure that absorbs energy with a vehicle body skeleton frame in the event of a collision from the vehicle longitudinal direction.

As a conventional engine support structure, there is one described in Patent Document 1, for example. In the structure described in Patent Document 1, as shown in FIG. 3 (a), a predetermined distance is provided below the vehicle body front skeleton frame 50 extending in the vehicle front-rear direction and above and below the vehicle body front skeleton frame 50. A sub frame 51 extending in the vehicle front-rear direction is disposed, and the front side of the vehicle body front skeleton frame 50 and the front side of the sub frame 51 are connected by a connecting member 52 extending vertically. An engine is mounted on the subframe 51.

Further, when a predetermined load or more is input from the front of the vehicle toward the rear due to a collision or the like, the vehicle body front skeleton member 50 is crushed and deformed to increase the efficiency of energy absorption with respect to the input load. .
JP 2002-160663 A

  Here, at the time of a collision, a collision input acts on the vehicle body skeleton frame 50 via the bumper 53. In order to reduce the deformation of the passenger compartment from the viewpoint of occupant protection, it is desirable to efficiently absorb the energy of the collision input by the deformation of the vehicle body skeleton frame 50 on the front side or the rear side in the vehicle longitudinal direction from the passenger compartment. The deformation mode in which the vehicle body frame 50 can absorb the collision input energy most efficiently is a mode in which the body frame 50 compresses and deforms in the axial direction.

However, in the prior art, as shown in the schematic diagram of FIG. 3 , the connecting member 52 that connects the sub frame 51 and the vehicle body frame 50 is rigidly fixed to the vehicle frame 50 and extends in the vehicle vertical direction. It has a predetermined length. For this reason, when a vehicle longitudinal force is input to the vehicle body skeleton frame 50 at the time of a collision, the center position of the rigidity of the integrated structure of the vehicle body skeleton frame 50 and the coupling member 52 that receives the collision input in the AA cross section of FIG. Since G is at the point G below the vehicle vertical direction from the collision input point, a moment A centered on the point G is applied, and the moment B acts also in the middle in the longitudinal direction . As shown in the schematic diagram shown in b), the vehicle body skeleton frame 50 may be deformed in the out-of-plane direction. In the case of deformation in the out-of-plane direction, the amount of the body skeleton frame 50 that is crushed in the compression direction (vehicle front-rear direction) is reduced, and the energy absorption amount is reduced.
The present invention has been made paying attention to the above points, and it is an object of the present invention to improve the energy absorption efficiency in the vehicle body skeleton frame with respect to a collision input in the vehicle longitudinal direction.

In order to solve the above-described problems, the present invention provides a vehicle body skeleton frame having an extending portion extending in the vehicle front-rear direction, a subframe that is disposed below the vehicle body skeleton frame and supports an engine, and the extension And a connecting member that connects the sub-frame and the sub-frame, wherein the sub-frame has a frame main body portion that extends vertically in the vehicle front-rear direction so as to face the extension portion, and the connection member, and the sub-frame a member Ru extends straight in a by and vertically separate member, the bottom is integrally fixed to the front end of the frame main body portion, an upper portion thereof in the extending portion in linked via a displaceable elastic member in the longitudinal direction of the vehicle for Rukoto, restraining force of the rotating direction of the vehicle width direction of the upper and the shaft are smaller than in its lower, the extending portion And connecting members The upper part is connected via an insulator in which the elastic body is inserted between an outer cylinder and an inner cylinder whose axis is directed upward and downward, and the inner cylinder is connected via a bolt that penetrates the interior vertically. And the outer cylinder is fixed to the upper portion of the connecting member .

  According to the present invention, the deformation mode of the vehicle body skeleton frame at the time of a collision from the vehicle body longitudinal direction is predominantly the compression deformation in the vehicle longitudinal direction even when the vehicle frame and the sub frame are spaced apart from each other in the vertical direction. As a result, collision energy can be absorbed efficiently.

Next, embodiments of the present invention will be described with reference to the drawings.
In the present embodiment, a vehicle configuration of a front engine in which an engine is mounted on the front side in the vehicle front-rear direction will be described as an example. FIG. 1 is a schematic side view showing an engine support structure of the present embodiment.
The body skeleton frame 1 includes a pair of left and right front skeleton side members 2 (extending portions) extending in the vehicle front-rear direction and a plurality of cross skeleton members extending in the vehicle width direction and connecting the left and right front skeleton side members 2. (Not shown). Each of the front skeleton side members 2 is bent downward at the portion reaching the dash panel to form an inclined portion 2a, and an extension in which the rear in the vehicle front-rear direction is disposed below and on both sides of the vehicle body floor relative to the inclined portion 2a. It is a side member 2b. Reference numeral 11 denotes a bumper.

Below the vehicle body skeleton frame 1, a sub-frame 3 is disposed to face each other with a predetermined distance in the vertical direction. Subframe 3, and the front framework side members 2 and the left and right of the frame body portion 4 facing extending in the vehicle both forward and backward directions up and down, and cross the sub members (not shown) for connecting the frame main body 4 of the left and right It is composed of The sub-frame 3 is elastically supported by the front skeleton side member 2 at the front end and the rear end of the frame body 4.

Next, the elastic support structure will be described.
The front end portion of the front skeleton side member 2 and the front end portion of the frame main body portion 4 are connected via a connecting member 5 extending vertically. The lower portion of the connecting member 5 is integrally coupled to the front end portion of the frame main body portion 4.
The upper part of the connecting member 5 is connected to the front end of the front skeleton side member 2 via an insulator 6. As shown in FIG. 2, the insulator 6 is configured by an elastic body 6c interposed between an inner cylinder 6a and an outer cylinder 6b that are arranged coaxially with their axes directed vertically. The outer cylinder 6b is fixed to the upper part of the connecting member 5 by press-fitting or the like, and the inner cylinder 6a is fixed to the front skeleton side member 2 via mounting bolts 12 penetrating the inner cylinder 6a. . Here, the length of the outer cylinder 6 b is shorter than the inner cylinder 6 a, and a predetermined gap is provided between the upper end surface of the outer cylinder 6 b and the lower surface of the front skeleton side member 2.
The end portion after the frame main body portion 4, through the similar insulator 8, is elastically supported at the bottom position of the inclined portion 2a of the front framework side members 2.
An engine 7 is mounted on the subframe 3 via a mount member 13.

Next, functions and effects of this embodiment will be described.
In the engine support structure described above, the connecting member 5 is integrally coupled to the subframe 3 so that both the members 5 and 3 have high rigidity, that is, a large restraining force in the rotational direction around at least the vehicle width direction. Linked in state. On the other hand, the connecting member 5 is connected to the front skeleton side member 2 via the elastic body 6c so that the connecting member 5 can be swung with each other, that is, connected in a state where the rigidity of the connecting portion is low. It is connected in a state where the restraining force in the rotational direction is small and close to zero. For this reason, when an input in the vehicle longitudinal direction is applied to the front skeleton side member 2, the rigidity in the vehicle vertical direction at the connection position (AA position in FIG. 1 ) between the front skeleton side member 2 and the connection member 5 is obtained. The center position G substantially coincides with the cross-sectional center of the front skeleton side member 2, and the front skeleton side member 2 of the front skeleton side member 2 is also located in the longitudinal direction of the front skeleton side member 2 (BB position in FIG. 1 ). The center position G ′ of rigidity in the direction substantially coincides with the cross-sectional center of the front skeleton side member 2.

  Accordingly, when a force in the vehicle longitudinal direction is input to the front skeleton side member 2 due to a collision, the moments around the rigid center positions G and G ′ due to the collision input are not generated or are small. Even if there is a distance between the frame and the sub-frame 3 and the sub-frame 3 is connected by the connecting member 5, the bending moment input to the front skeleton side member 2 by the reaction force of the sub-frame 3 at the time of collision can be reduced. As a result, the deformation in the compression direction becomes dominant with respect to the vehicle front-rear direction input at the time of the collision, and the front skeleton side member 2 does not deform in the out-of-plane direction, as shown in FIG. The energy absorption amount increases.

Further, as described above, as the front skeleton side member 2 is compressed in the vehicle front-rear direction, the upper portion of the outer cylinder 6 b fixed to the connection member 5 is connected to the connection member 5, although the upper portion thereof is inclined in the vehicle front-rear direction. Since a predetermined gap is provided between the front skeleton side member 2 and the lower surface of the front skeleton side member 2, the connection between the front skeleton side member 2 and the connecting member 5 is continued until the upper end of the outer cylinder 6 b comes into contact with the front skeleton side member 2. It is possible to prevent the restraining force at the portion from increasing. Even if the upper end of the outer cylinder 6b abuts against the front skeleton side member 2 and the restraining force in the rotational direction is increased, it is much smaller than the restraining force at the connecting portion between the connecting member 5 and the subframe 3. The vertical bending moment input to the front skeleton side member 2 is small, so that the deformation in the compression direction tends to remain dominant.
Further, since the front end portion and the rear end portion of the subframe 3 on which the engine 7 is mounted are elastically supported by the front skeleton side member 2 via the insulators 6 and 8, the subframe 3 mounted by the vibration of the engine 7 is used. It is difficult to transmit the vibration of the frame 3 to the front skeleton side member 2. That is, noise and vibration performance can be improved by preventing the vibration of the sub-frame 3 that is vibrated by the vibration of the engine 7 from being transmitted to the front skeleton side member 2.

In the above embodiment, the case where the present invention is applied to the vehicle configuration of the front engine is illustrated. However, the present invention can be applied even to the vehicle configuration of the rear engine. Obtainable.

It is a typical side view which shows the engine support structure which concerns on embodiment based on this invention, Comprising: (a) shows the state before a deformation | transformation, (b) shows the state after a deformation | transformation, respectively. It is sectional drawing which shows the connection structure with the sub member of the front frame side member via the connection member which concerns on embodiment based on this invention. It is a typical side view explaining the conventional engine support structure, Comprising: (a) is before a deformation | transformation. The state (b) shows the state after deformation.

Explanation of symbols

1 Body frame 2 Front frame side member (extension part)
3 Subframe 4 Frame body portion 5 Connection portion 6 Insulator 6a Inner tube 6b Outer tube 6c Elastic body 7 Engine 10 Elastic body 12 Mounting bolt

Claims (2)

A vehicle body skeleton frame having an extending portion extending in the longitudinal direction of the vehicle, a subframe disposed below the vehicle body skeleton frame to support the engine, and a connecting member connecting the extension portion and the subframe; An engine support structure comprising:
The sub-frame has a frame main body extending vertically in the vehicle front-rear direction so as to face the extended portion.
The connecting member, and the sub-frame a member Ru extends straight in a by and vertically separate member, the bottom is integrally fixed to the front end of the frame main body portion, an upper portion thereof above extends in Rukoto linked via a displaceable elastic member in the longitudinal direction of the vehicle relative to the parts, restraining force of the rotating direction is smaller than the lower portion thereof to the vehicle width direction of the upper and the shaft,
The extension part and the upper part of the connecting member are connected to each other via an insulator in which the elastic body is inserted between an outer cylinder and an inner cylinder whose axis is directed vertically, and the inner cylinder is connected to the inner cylinder. An engine support structure , wherein the outer cylinder is fixed to an upper portion of the connecting member, and is fixed to the extending portion via a bolt passing through the upper and lower sides . The engine support structure according to claim 1 , wherein a vertical gap is provided between the upper end of the connecting member and the upper end of the outer cylinder, and the extending portion.

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