JP5158361B2 - Body front structure - Google Patents

Description

  The present invention relates to a vehicle body front portion structure, and more particularly to a vehicle body front structure that can improve safety when a vehicle central portion in the vehicle width direction collides with a pole-shaped obstacle.

  The front part of the vehicle body generally connects the left and right end parts of the bumper reinforcement extending in the vehicle width direction at the front end of the vehicle body to the front ends of the pair of left and right front side frames, more specifically via a crash can. Structure is adopted. That is, as the vehicle body front structure, a structure in which the left and right front side frames function as a main shock absorbing member at the time of a frontal collision is adopted.

  The impact safety performance test for frontal collisions is conducted in two ways. The first aspect is a full wrap frontal collision and the second aspect is an offset frontal collision. In the full-wrap frontal collision test, the vehicle is made to collide with a concrete barrier at a predetermined speed. In the offset frontal collision test, one side of the vehicle (overlap ratio 40%) is subjected to frontal collision with a honeycomb-shaped barrier.

  Patent Document 1 proposes an invention that absorbs the collision energy by buckling of the front end portion of the front side frame at the initial stage of the collision in the full-wrap frontal collision and the offset frontal collision and relaxes the occupant's deceleration in the late stage of the collision. . Specifically, in Patent Document 2, pipes extending in the vehicle width direction are provided between the rear end portions of the left and right front side frames having a rectangular cross section, and the left and right ends of the pipes are provided on the inner side surface of the front side frame. A structure to connect is proposed. According to this invention, when the power plant retreats due to a collision, the retreating power plant causes the connecting pipe extending in the vehicle width direction to bend backward, and the rear end portions of the left and right front side frames are bent by the bending of the connecting pipe. By bending the vehicle inward in the vehicle width direction, the deceleration of the occupant in the latter half of the collision can be mitigated.

  Patent Document 2 discloses a so-called horizontal engine in which an engine output shaft is mounted in an engine room with a vehicle width direction, and a transaxle connected to the so-called horizontal engine, in which a transaxle side is mounted on a front side frame adjacent thereto. Regarding the type mounting member, he points out the problems and proposes an improvement plan. Here, the suspension mount member employs a configuration in which a bush is disposed in a space between the end face of the transaxle and the front side frame.

JP 2002-120752 A JP 2000-168624 A

  Incidentally, as described above, typical examples of the frontal collision include a full lap collision and an offset collision, but there are, of course, various aspects in an actual frontal collision accident. One of them is the case of crashing into a power pole or road sign post planted on the side of the road. If the center of the vehicle in the width direction of the vehicle collides with a pole-shaped obstacle against this pole-shaped obstacle, the bumper reinforcement generally does not have the strength to catch it. As a result, the pole may collide with the power plant including the engine and the mount member may be destroyed.

  An object of the present invention is to provide a vehicle body front structure that can suppress a power plant from retreating when a central portion in the vehicle width direction collides with an obstacle that does not have a spread in the vehicle width direction, such as a pole. There is to do.

According to the present invention, the above technical problem is
An engine room located at the front of the vehicle body,
Left and right front side frames extending in the longitudinal direction of the vehicle body and having a rectangular closed cross-sectional structure;
A power plant housed in the engine room, in which a horizontally placed engine with an output shaft directed in the vehicle width direction and a transaxle connected to the output shaft of the engine are integrated side by side in the vehicle width direction;
In a vehicle body front structure having first and second mounting members for mounting the power plant on the left and right front side frames, respectively.
The first mount member for mounting the end face of the engine on a front side frame adjacent to the engine is disposed in front of the front wheel suspension tower;
The first mount member is
An inverted L-shaped first support shaft that is fastened to the end surface of the engine and extends outwardly in the vehicle width direction, and extends downward;
A first elastic body surrounding a portion extending downward of the inverted L-shaped first support shaft;
A first outer cylinder surrounding the first elastic body;
Front and rear legs extending downward from the first outer cylinder and having lower ends connected to the upper surface of the front side frame;
This is achieved by providing a vehicle body front portion structure having an extension portion extending from the inverted L-shaped first support shaft to a position facing the front wall of the front wheel suspension tower from the front.

  According to the vehicle body front structure of the present invention, the first elastic body included in the first mount member is accommodated in the first outer cylinder that is opened up and down, and the first outer cylinder is disposed on the front side via the front and rear legs. Since it is fixed to the frame, even if a collision load is applied to the power plant due to an impact during a frontal collision such as a pole collision, this can prevent the first elastic body from being destroyed. . In addition, even if a collision load is applied to the power plant and the front and rear legs are deformed by the impact and the first outer cylinder is retracted, the extension extending from the first support shaft is received by the front wheel suspension tower. Power plant retreat can be suppressed.

According to a preferred embodiment of the present invention,
A receiving member is provided on the front wall of the front wheel suspension tower. The receiving member is provided with upper and lower walls and extends in the vehicle width direction and forms a groove for receiving the tip portion of the extension. According to this embodiment, it is possible to stably receive the extension portion that moves backward by the receiving member provided on the front wall of the front wheel suspension tower.

According to a preferred embodiment of the present invention,
A portion of the inverted L-shaped first support shaft extending from the engine end surface in the vehicle width direction is configured by a plate-like bracket, and the extension portion is formed integrally with the plate-like bracket. The bracket extension portion extends in a direction in which the tip portion approaches the front wall of the front wheel suspension tower. According to this embodiment, since the tip end portion of the bracket extension portion extends in a direction approaching the front wall of the front wheel suspension tower, it can be received by the suspension tower from the initial stage of retreat of the power plant. In other words, since the suspension tower receives the bracket extension from the early stage of retreat where the acceleration is still small, it is possible to prevent the bracket extension from being broken.

According to a preferred embodiment of the present invention,
The second mount member for mounting the power plant transaxle on the front side frame adjacent thereto is an opening formed on the inner side wall in the vehicle width direction of the front side frame of the rectangular closed cross-sectional structure. A second outer cylinder having an outer shape complementary to the shape of the first outer cylinder and inserted into the front side frame through the opening; a second elastic body housed in the outer cylinder; one end of the second outer cylinder; A second support shaft surrounded by two elastic bodies; the other end of the second support shaft is fastened to the transaxle case. According to this embodiment, since the second elastic body included in the second mount member is housed inside the front side frame, it collides with the power plant due to an impact during a frontal collision such as a pole collision. Even if a load is applied, the impact load applied to the power plant is directly transmitted to the front side frame without causing the elastic body to break down, and the impact energy absorption function of the front side frame is used for the impact. Can be relaxed. In addition, the conventional suspension mount member has a member such as an elastic body located above the transaxle. According to this embodiment, the elastic body is housed inside the front side frame. Therefore, the upper area of the transaxle can be used as an installation space for accessories, batteries, and the like.

  Other objects and advantages of the present invention will become apparent from the following detailed description of the preferred embodiments.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a plan view of a vehicle body front structure according to the embodiment. FIG. 2 is a vehicle body front structure according to the embodiment as viewed from the side. First, referring to FIG. 2, reference numeral 10 indicates a dash panel, and the vehicle compartment 12 and the engine room 14 are partitioned by the dash panel 10. The vehicle compartment 12 is provided with an instrument panel 16, a brake pedal 18, an accelerator pedal, and the like. Reference numeral 20 denotes a front window.

  Referring to FIGS. 1 and 2, left and right front side frames 22 extending in the longitudinal direction of the vehicle body over the entire area of engine room 14 are disposed in the lower region of engine room 14. 22 has a rectangular closed cross-sectional structure. As is known, bumper reinforcements 24 extending in the vehicle width direction are connected to the front ends of the left and right front side frames 22 via a crash can 26. A sub-frame 28 positioned below the front side frame 22 is further disposed below the engine room 14. Reference numeral 30 is a front wheel.

  An internal combustion multi-cylinder engine 32 is mounted in the engine room 14 as a power plant. The engine 32 is a water-cooled in-line four-cylinder engine and is mounted in the engine room 14 with the engine output shaft directed in the vehicle width direction as best seen in FIG. That is, the engine 32 mounted in the engine room 14 is a horizontal reciprocating engine, and the engine 32 is integrated with a transaxle 34 connected to the rear end thereof. In other words, the engine 32 and the transaxle 34 constituting the power plant are arranged side by side in the vehicle width direction and integrated.

  The transaxle 34 includes a transmission case 36 that houses a transmission connected to the engine output shaft, and a differential case 38 that is disposed behind the transmission case and incorporates a differential gear, and extends from the differential case 38 in the vehicle width direction. The left and right front wheels 30 are driven by the left and right drive shafts. This automobile is a front-wheel drive type vehicle, but the present invention can also be applied to a four-wheel drive type vehicle.

  The engine 32 is a water-cooled engine, and the cooling water of the engine 32 is cooled by a radiator 40 fixed to a shroud panel (not shown) between the front end portions of the left and right front side frames 22. The horizontally installed engine 32 employs front intake and rear exhaust types, and an intake pipe 42 is connected to the front surface of the cylinder head of the engine 32 and an exhaust pipe 44 is connected to the rear surface (FIG. 2). ).

  The sub-frame 28 is configured by a perimeter frame having a substantially rectangular frame shape with a member 28a extending in the vehicle width direction at the rear and in the vicinity of the crash can 26, and each of the left and right front ends thereof is supported by a long bolt 46. The front side frame 22 is fixed to the front end portion. The front wheel suspension mechanism 48 has lower arm pivot points constituting the front wheel suspension mechanism 48 at both left and right ends of the rear portion of the subframe 28. In the figure, reference numeral 50 indicates a front wheel steering link mechanism.

  A power plant such as the engine 32 disposed in the engine room 14 is mounted on the left and right front side frames 22 via first and second mounting members 52 and 54, and the rear end of the engine 32 is Via a third mount member 56, the rear end portion of the subframe 28 is connected to a main body portion 28a extending in the vehicle width direction (FIG. 1).

  The first mounting member 52 is disposed between the engine 32 and the front side frame 22 adjacent thereto (the right front side frame in the illustrated example). On the other hand, the second mounting member 54 is disposed between the end portion of the transaxle 34 and the front side frame 22 (the left front side frame in the illustrated example) adjacent to the end portion of the transaxle 34. Both of the mounting members 52 and 54 are disposed adjacent to and in the vicinity of the left and right suspension towers 58.

  FIG. 3 is a plan view of the vicinity of the first mount member 52 on the engine 32 side, and FIG. 4 is a longitudinal sectional view of the first mount member 52. 3 and 4, the first mount member 52 on the engine 32 side has a plate-like bracket 60 bolted to the end face 32a of the engine 32, that is, the end face of the cylinder block. Extends outward in the direction. The plate-like bracket 60 has a bracket extension 62 that extends outward in the vehicle width direction beyond the front side frame 22, and the bracket extension 62 is formed integrally with the plate-like bracket 60. The bracket extension portion 62 extends to a position facing the front wall 58a of the suspension tower 58, and the bracket extension portion 62 extends in a direction in which the front end portion approaches the front wall 58a of the suspension tower 58. In the figure, reference numeral 64 indicates an apron reinforcement, and reference numeral 66 in FIG. 4 indicates an apron panel.

  The front side frame 22 is bolted to the upper surface of the front side frame 22 by two front and rear legs 68 and 70 spaced in the longitudinal direction of the vehicle body. The outer cylinder 72 is welded, and the inner and outer double sleeves 74 and 76 are opened in the first outer cylinder 72, and the first bush 78 is interposed between the inner and outer sleeves 74 and 76. Is housed. A female screw is provided at the lower end of the inner sleeve 74.

  The bracket 60 is formed with a bolt insertion hole in the upper region of the front side frame 22, and the bolt 80 inserted from above into the bolt insertion hole is inserted into the inner sleeve 74. Thus, the bracket 60 fixed to the engine 32 is coupled to the upper surface of the front side frame 22 via a bush 78 that is an elastic body.

  FIG. 5 is a plan view of an installation site of the first mount member 52. With reference to FIGS. 3 to 5, a bracket receiving member 82 is joined to the front wall 58 a of the suspension tower 58 by welding in relation to the first mount member 52 described above. The bracket receiving member 82 has a groove 84 that is defined by upper and lower walls 82a and 82b and an end wall 82c at the outer end in the vehicle width direction and is open in the front and in the vehicle width direction. The tip portion of the bracket extension 62 is received. 4 indicates the suspension upper arm, and the imaginary line 88 indicates the knuckle arm.

  The first mount member 52 is connected to an end surface 32a of the engine 32 and extends outward in the vehicle width direction, a bolt 80 extending downward from the bracket 60, and an inner sleeve 74 screwed thereto. A first support shaft that is bent in an L shape is formed, and a portion extending below the inverted L-shaped first support shaft, that is, a portion extending in the vertical direction is interposed through a bush 78 that is a first elastic body. The engine 32 is elastically supported by the front side frame 22.

  Even if a collision load is applied to the power plant and the front and rear legs 68, 70 are deformed by the impact and the first outer cylinder 72 is retracted, the bracket extension 62 is received by the suspension tower 58, so the power plant is retracted. Can be suppressed.

  Moreover, since the front-end | tip part of the bracket extension part 62 is extended in the direction approaching the front wall 58a of the suspension tower 58, it can be received by the suspension tower 58 from the retreat initial stage of a power plant.

  In addition, since the tip end portion of the bracket extension 62 is received in the groove 84 extending in the vehicle width direction defined by the bracket receiving member 82 having the upper and lower walls 82a and 82b, the bracket receiving member 82 stably supports the bracket. The front end portion of the extension portion 62 can be received. Note that the tip of the bracket extension 62 is displaced up and down and left and right by a predetermined amount due to the swing of the engine 32 and the transaxle 34 caused by torque fluctuations during engine startup or operation. For this reason, the separation distance between the upper and lower walls 82a and 82b of the bracket receiving member 82 is set so as not to interfere with the tip of the bracket extension 62 that moves up and down as the engine 32 and the transaxle 34 swing. The

  Of course, since the suspension tower 58 is designed to have high rigidity, the first mount member 52 is destroyed by the retreat of the engine 32 and the bracket extension 62 is retreated, as schematically shown in FIG. However, the bracket extension 62 can be received by the suspension tower 58.

  FIG. 6 is a plan view of a portion related to the second mount member 54 on the transaxle 34 side. FIG. 7 is an exploded perspective view of the second mount member 54, the transaxle 34 (transmission case 36) related thereto, and the front side frame 22 as viewed obliquely from the front, and FIG. 8 shows the second mount member 54. FIG.

  Referring mainly to FIGS. 7 and 8, the second mount member 54 has a second inverted L-shaped member 90 constituting a support shaft. The second inverted L-shaped member 90 has a vertical portion 92 extending vertically and a horizontal portion 94 extending outward from the upper end of the vertical portion 92 in the vehicle width direction. A plurality of bolt insertion holes 72a are formed. The second inverted L-shaped member 90 is fastened to the end surface 36 a of the transmission case 36 using a bolt 96 inserted into the bolt insertion hole 92 a of the vertical portion 92. The horizontal portion 94 of the second inverted L-shaped member 90 extends outward in the vehicle width direction so as to coincide with the vehicle width direction, which is the direction in which the power plants including the engine 32 and the transaxle 34 are arranged. The mass of the plant can be supported by the front side frame 22 without difficulty.

  The horizontal portion 94 of the second inverted L-shaped member 90 is surrounded by a bush 98 that is a second elastic body, and the second bush 98 is surrounded by a second outer cylinder 100 having a rectangular cross section. Contained. That is, the second outer cylinder 100 is disposed with its axis line directed in the vehicle width direction, and a bush 98 that is a second elastic body is accommodated in the second outer cylinder 100. The second outer cylinder 100 opened toward the inside and outside in the vehicle width direction has an entire circumferential flange 102 at the inner end in the vehicle width direction, and a plurality of bolt insertion holes 102 a are formed in the entire circumferential flange 102. (FIG. 7).

  The front side frame 22 has rectangular openings 22a on both side walls (FIG. 7), and the rectangular second outer cylinder 100 is inserted into the openings 22a on both the inner and outer side walls. . That is, the outer end portion of the rectangular second outer cylinder 100 passes through the rectangular opening 22a on the outer side in the vehicle width direction, so that when a collision load is applied to the power plant, the second outer cylinder The collision load can be transmitted to the front side frame 22 in the axial direction while the rotation of 100 is restricted by the rectangular opening 22. Here, the outer cylinder 100 has an outer shape complementary to the shape of the opening 22a of the front side frame 22, and the entire circumferential flange 102 is brought into contact with the peripheral portion of the opening 22a. A portion of the front side frame 22 that receives the second outer cylinder 100 is preferably reinforced by a stiffener 104 (FIG. 7) disposed inside the front side frame 22, and a nut 106 is previously attached to the stiffener 104. It is better to weld.

  The operation of installing the second mount member 54 on the front side frame 22 can be positioned by inserting the second outer cylinder 100 into the front side frame 22 through the opening 22a opened in the lateral direction. Since the bolt 108 inserted through the bolt insertion hole 102a of the entire peripheral flange 102 of the outer cylinder 100 can be screwed into the nut 106, the second mount 54 can be attached to the front side frame by accessing from the power plant side. 22 can be fastened.

  By fastening the second mount member 54 to the front side frame 22, one end of the inverted L-shaped member 90 constituting the second support shaft is fixed via a bush 98 in the front side frame 22. The end is fixed to the end surface 36 a of the transmission case 36, whereby the power plant is elastically supported by the front side frame 22.

  A bump or the like crashes into the center portion of the bumper reinforcement 24 in the vehicle width direction, the bumper reinforcement 24 bends in the center portion of the vehicle width direction, and enters the engine room 14 to include the engine 32 and the transaxle 34. When a collision load is applied to the power plant, a part of the collision load is transmitted to the front side frame 22 via the second mount member 54, and the collision load transmitted to the front side frame 22 is transmitted to the front side frame 22. Therefore, the collision energy can be reduced by using the collision energy absorption function of the front side frame 22.

It is the figure which planarly viewed the vehicle body front part structure of the Example. It is the figure which looked at the vehicle body front part structure of the Example from the side. It is the perspective view which expands and shows the 1st mount member which mounts the engine side of the power plant containing a horizontal installation engine in the front side frame adjacent to this, and the element adjacent to this. It is a longitudinal cross-sectional view of a 1st mount member. It is the fragmentary top view which planarly viewed the 1st mount member and the element relevant to this. It is the fragmentary top view which planarly viewed the 2nd mounting member by the side of a transaxle, and the element relevant to this. It is a disassembled perspective view which expands and shows the 2nd mounting member which mounts the transaxle side of the power plant containing a horizontal installation engine in the front side frame adjacent to this, and the element adjacent to this. It is a longitudinal cross-sectional view of the 2nd mount member fastened to the front side frame. It is a perspective view corresponding to Drawing 3 showing typically a state when a power plant retreats by front collision and the 1st mount member is destroyed.

Explanation of symbols

14 Engine Room 22 Front Side Frame 22a Openings on Both Side Walls of Front Side Frame 32 Engine (Power Plant)
32a End face 34 of engine Transaxle (power plant)
36 Mission case 36a End surface 52 of the mission case 52 First mount member 54 on the engine side Second mount member 58 on the mission case side Suspension tower 58a Front wall 60 of the suspension tower Bracket (first mount member)
62 bracket extension 68 front leg 70 rear leg 72 first outer cylinder 78 first bush 82 bracket receiving member 82a upper wall 82b of bracket receiving member 84 lower wall of bracket receiving member 90 groove 90 of bracket receiving member second inverted L-shape Member (support shaft) (second mount member)
92 Vertical portion 94 of the second inverted L-shaped member 94 Horizontal portion 98 of the second inverted L-shaped member Bush (elastic body) of the second mount member
100 Second outer cylinder

Claims (4)

An engine room located at the front of the vehicle body,
Left and right front side frames extending in the longitudinal direction of the vehicle body and having a rectangular closed cross-sectional structure;
A power plant housed in the engine room, in which a horizontally placed engine with an output shaft directed in the vehicle width direction and a transaxle connected to the output shaft of the engine are integrated side by side in the vehicle width direction;
In a vehicle body front structure having first and second mounting members for mounting the power plant on the left and right front side frames, respectively.
The first mount member for mounting the end face of the engine on a front side frame adjacent to the engine is disposed in front of the front wheel suspension tower;
The first mount member is
An inverted L-shaped first support shaft that is fastened to the end surface of the engine and extends outwardly in the vehicle width direction, and extends downward;
A first elastic body surrounding a portion extending downward of the inverted L-shaped first support shaft;
A first outer cylinder surrounding the first elastic body;
Front and rear legs extending downward from the first outer cylinder and having lower ends connected to the upper surface of the front side frame;
A vehicle body front structure comprising: an extension portion extending from the inverted L-shaped first support shaft to a position facing the front wall of the front wheel suspension tower from the front.   The receiving member for forming the groove | channel which is provided in the front wall of the said front-wheel suspension tower, is provided with an up-and-down wall, is extended in the said vehicle width direction, and receives the front-end | tip part of the said extension part. Body front structure. A portion extending in the vehicle width direction from the end surface of the engine of the inverted L-shaped first support shaft is constituted by a plate-shaped bracket,
The extension is composed of a bracket extension formed integrally with the plate-like bracket,
The vehicle body front part structure according to claim 2, wherein the bracket extension part extends in a direction in which a tip part thereof approaches a front wall of the front wheel suspension tower. The second mount member for mounting the power plant transaxle on a front side frame adjacent thereto is provided.
The rectangular closed cross-sectional structure has an outer shape complementary to the shape of the opening formed in the side wall in the vehicle width direction of the front side frame, and is inserted into the front side frame through the opening. A second outer cylinder;
A second elastic body housed in the outer cylinder;
A second support shaft having one end surrounded by the second elastic body;
The vehicle body front part structure according to any one of claims 1 to 3, wherein the other end of the second support shaft is fastened to a case of the transaxle.

Images