JP2004345387A - Power unit supporting structure of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve both of a vibration noise performance (silence) and a steering stable performance of a vehicle, in particular improve a steering stable performance or a starting performance at the time of acceleration and deceleration, and improve steering stability at the time of cornering without developing an expensive engine mount. <P>SOLUTION: A power unit having a transverse engine is supported at a supporting position above a center of gravity of a power unit by a first bracket 12, and a second bracket 18 is mounted on a front face of a strut housing 2. The first bracket 12 and the second bracket 18 are connected with a mount body 10A, and the mount body 10A is mounted on a top face of a side frame 1. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a support structure for supporting a power unit including a vehicle engine and a transmission on a vehicle body.
[0002]
[Prior art]
A power unit including a vehicle engine and a transmission is elastically supported by a vehicle body at a plurality of locations. As this elastic support structure, a mount structure via a cushion rubber is adopted, but the setting of the support points by the cushion rubber and the support structure at each support point reduce transmission of engine vibration to the vehicle body side. It is extremely important in reducing vehicle interior noise, and various developments have conventionally been made according to the type of engine, the type of mounting, and the like.
[0003]
According to Patent Document 1 below, the spring constant of the cushion rubber in the peripheral mounts (left and right front mounts and rear mounts) is set low with emphasis on vibration noise reduction, and the center mount is further mounted almost directly below the center of gravity of the power unit. A support structure has been proposed in which the center mount bears the weight of the power unit itself.
[0004]
[Patent Document 1]
Published Japanese Utility Model Application No. 7-8035
[Problems to be solved by the invention]
When the spring constant of the cushion rubber is set low as in the prior art described above, the vibration noise performance can be improved. However, the displacement of the power unit increases with this, and good steering stability can be obtained. Disappears. In particular, in a vehicle equipped with a vertical engine, if the displacement of the power unit in the front-rear direction is large, there arises a problem that the steering stability performance or the starting performance during acceleration / deceleration decreases.
[0006]
In order to cope with this, it is conceivable that a center mount is provided as in the above-described conventional technology and the displacement of the power unit is suppressed by increasing the cushion rubber rigidity, but the center mount which supports almost the entire weight of the power unit can be considered. In order to increase the rubber rigidity, it is necessary to develop an expensive mount, and there is also a problem in the durability of the center mount itself.
Further, in the conventional support structure, since the power unit is supported by the vehicle body at a position lower than the center of gravity, the resistance against the tilt of the power unit is weak, and it is difficult to suppress the displacement of the power unit during cornering. Therefore, the input to the cushion rubber supporting the power unit at the time of cornering becomes large, causing a problem that the toe change of the suspension becomes large and the steering stability performance deteriorates.
[0007]
The present invention has been proposed to address such a problem, and achieves both improvement in vibration noise performance (quietness) and improvement in steering stability performance of a vehicle without developing an expensive engine mount. In particular, it is an object of the present invention to provide a vehicle power unit support structure capable of improving steering stability or starting performance during acceleration / deceleration and improving steering stability during cornering.
[0008]
[Means for Solving the Problems]
In order to achieve such an object, a power unit support structure for a vehicle according to the present invention has the features according to the following claims.
[0009]
The invention according to claim 1 is a power unit support structure in which a power unit of a vehicle is supported on a vehicle body via a cushion rubber, wherein a support position above a center of gravity of the power unit and a support surface facing a traveling direction of the vehicle body are provided. Are supported by the support member.
[0010]
The invention according to claim 2 is characterized in that the support surface is a front surface of a strut housing in which a front suspension is stored, based on the above-described configuration.
[0011]
The invention according to claim 3 is characterized in that the strut housing is provided with a closed section forming material that forms a closed section in a front portion on the premise of the above configuration.
[0012]
The invention according to claim 4 is characterized in that, on the premise of the above-described configuration, the closed-section forming material is provided so as to be overlapped at a joint between the strut housing and the front wheel apron.
[0013]
The invention according to claim 5 is characterized in that, on the premise of the above configuration, the closed section forming material is provided along the top and bottom and is divided into a plurality.
[0014]
The invention according to claim 6 is based on the premise that the power unit has a vertical engine mounted on a front cross member and a rear cross member connecting left and right side frames extending in the front-rear direction of the vehicle body, The support member includes a first bracket attached to the mount body and extending toward the power unit, and a second bracket attached to the mount body and extending toward the vehicle body. The mount body has a cushion rubber, It is characterized in that it is mounted on one of the side frames.
[0015]
The invention according to claim 7 is based on the above-mentioned feature, wherein the mount main body is attached to a reinforcing member fixed according to a corner portion in the side frame, and the second bracket is provided in the strut housing. It is attached to a reinforcing member fixed to a closed section.
[0016]
The invention according to each claim having such features can obtain the following effects.
[0017]
For one, the support position above the center of gravity of the power unit and the support surface facing the direction of travel on the vehicle body side are supported by support members, so that displacement and tilt along the direction of travel of the power unit are effectively controlled. can do. As a result, even when the vibration noise performance is improved by setting the spring constant of the cushion rubber in another mount portion to be low, the displacement of the power unit and the vehicle body in the front-rear and left-right directions can be regulated by the above-described support member. It is possible to achieve both noise performance and steering stability performance.
[0018]
In addition, by supporting the upper part of the power unit, displacement due to inclination of the power unit at the time of cornering can be suppressed, and the inertial force acting on the power unit at the time of cornering can be reduced. As a result, the input to the cushion rubber supporting the power unit is reduced, so that the toe change of the suspension is reduced, and the steering stability at the time of cornering can be improved.
[0019]
Furthermore, since the support surface on the vehicle body side of the support member is located on the front surface of the strut housing in which the front suspension is stored, there is no need to add a new support surface facing the traveling direction to the vehicle body structure. The above-mentioned effect can be obtained by utilizing the above.
[0020]
In addition, since the strut housing on which the support surface is formed is provided with a closed section forming material having a closed section formed in the front part vertically, the rigidity of the strut housing can be increased while reducing the weight. In addition, displacement of the power unit due to deformation of the vehicle body can be suppressed.
[0021]
As a specific configuration of the closed section forming material, it is possible to provide effective reinforcement by overlapping the strut housing and the front wheel apron at the joint surface, and press forming by forming into a plurality of divided forms , The formation and attachment can be simplified, and the productivity is good and efficient reinforcement is possible.
[0022]
In particular, by adopting the above-described support structure in a power unit including a vertical engine, it is possible to improve the steering stability or the starting performance during acceleration / deceleration. Further, by attaching the support member to the mount body having the cushion rubber and supporting the mount body on the left and right side frames, it is possible to realize elastic support in which displacement in the front, rear, left, and right directions is suppressed.
[0023]
Further, by attaching the mount body to the reinforcing member fixed according to the corners in the side frame, the mounting strength of the support portion can be improved without increasing the rigidity of the side frame itself. Further, the mounting strength of the support portion can be improved by supporting the bracket (second bracket) on the vehicle body side of the support member described above on the reinforcing member fixed in the strut housing. Thereby, the displacement of the power unit can be effectively suppressed without particularly increasing the weight of the vehicle body.
[0024]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory diagram showing a power unit support structure according to an embodiment of the present invention, and is an explanatory diagram showing details of a mount structure added to a conventional mount structure. According to the mounting structure 10, the engine-side stay 11 attached to the support position above the center of gravity of the power unit (not shown) is coupled to the first bracket 12 with the screw 20, and the first bracket 12 is mounted via the dynamic damper 13 on the mounting body. It is connected to the upper surface of 10A by a screw 21. The mount body 10A has a cushion rubber portion 14, and mounting feet 15, 16 extending from the side or bottom thereof are attached to the side frame 1 extending in the front-rear direction by screws 22, 23. A second bracket 18 is connected to the connecting portion 17 on the side of the mount main body 10 </ b> A with a screw 24, and the second bracket is attached to the front surface of the strut housing 2 with a screw 25. The strut housing 2 houses a Freon suspension therein, and serves as a mounting support for the front suspension.
[0025]
As a result, the support position above the center of gravity of the power unit and the front surface of the strut housing 2 (the support surface on the vehicle body side facing the vehicle traveling direction) are connected to the first bracket 12 extending toward the power unit and the second bracket 18 extending toward the vehicle body. The mount main body 10A to which the first bracket 12 and the second bracket 18 are attached is attached to at least one of the left and right side frames 1. As the first bracket 12 and the second bracket 18 connecting the vehicle body and the power unit, a high-rigidity and lightweight aluminum member can be adopted. In the illustrated example, the above-described mount structure 10 is provided on the right side of the vehicle body front. However, it may be provided on the left side of the vehicle body front side, or may be provided on both left and right sides.
[0026]
FIG. 2 is an explanatory view showing a support structure of the entire power unit (FIG. 2A is a plan view, FIG. 2B is a side view, and the same parts as those in FIG. Is partially omitted.). Here, an example is shown in which the above-described mount structure 10 is provided only on the right side with respect to the front of the vehicle body. The power unit 3 has a front cross member (not shown) connecting left and right side frames 1 (not shown on the left) extending in the front-rear direction of the vehicle body, and a vertical engine mounted on the rear cross member 6A. The basic support structure of the power unit 3 is three-point support via a cushion rubber. Two points of support are provided by front cushion rubbers 4 and 5 provided on the front side, and a rear cushion rubber 6 provided on the rear side. Is supported by one point. Further, a pitching stopper 7 is provided above the power unit 3 as required.
[0027]
The above-described mount structure 10 is additionally provided to such a basic support structure. Accordingly, the displacement of the power unit 3 with respect to the vehicle body is restricted by the action of the mount structure 10 while the vibration constant is suppressed by setting the spring constants of the front cushion rubbers 4 and 5 and the rear cushion rubber 6 to be low. Steering stability can be secured.
[0028]
3A and 3B are explanatory views showing a vehicle-body-side mounting portion to which the above-described mounting structure 10 is mounted (FIG. 3A is an overall perspective view, FIG. 3B is an XX cross-sectional view, and FIG. ) Is a YY sectional view). The mounting portion on the vehicle body side to which the mounting structure 10 is mounted is formed on the upper surface 1A of the side frame 1 and the front surface (support surface) 2A of the strut housing 2 (here, reference numeral 8 denotes a wheel apron). In this mounting portion, a reinforcing member for improving rigidity is arranged to improve steering stability while suppressing an increase in the overall weight of the vehicle body.
[0029]
In other words, a closed-section forming material 2B that forms a closed-section structure on the back side of the support surface 2A is added to the mounting portion of the mounting structure 10 to which the second bracket 18 is mounted, so that the closed-section structure in the strut housing 2 is added. A reinforcing member 30 having a screw coupling portion 30a is fixed therein, and a mounting portion to which the mounting feet 15 and 16 of the mount body 10A are mounted according to a corner facing the upper surface 1A in the side frame 1. The reinforcing member 31 having the screw connection portion 31a is fixed. Then, the second bracket 18 is attached to the screw coupling part 30a by the screw 25, and the mounting feet 15, 16 are attached to the screw coupling part 31a by the screws 22,23. By the addition of such a reinforcing member and the adoption of the closed cross section, the weight can be reduced as compared with the case where the constituent materials of the side frame 1 and the strut housing 2 themselves are strengthened. The rigidity can be increased.
[0030]
FIG. 4 is an explanatory view showing the structure on the vehicle body side (the same parts as those described above are denoted by the same reference numerals). The structure on the vehicle body side is formed by joining three pressed materials of the side frame 1, the strut housing 2, and the wheel apron 8. Then, a closed section forming material 2 </ b> B vertically extending with respect to the side frame 1 along the vertical direction with respect to the joint portion S between the strut housing 2 and the wheel apron 8 is provided. Thus, as described above, a closed cross-sectional structure is formed on the back side of the front surface 2 </ b> A in the strut housing 2, and a closed cross-sectional structure is formed vertically in front of the strut housing 2. The closed section forming material 2B is formed by being divided into three members, an upper member 2B1, a middle member 2B2, and a lower member 2B3, and has a closed cross section formed along the arch shape of the wheel apron 8.
[0031]
5A and 5B are explanatory views showing the setting state of the closed section forming material 2B (FIG. 5A is a front view (view from the front of the vehicle body), FIG. 5B is an AA sectional view, and FIG. c) is a BB cross-sectional view, and FIG. 4D is a CC cross-sectional view. As shown in the drawing, the formed closed cross section is formed toward the front surface (support surface) 2A of the strut housing 2 at the upper part of the closed cross section forming material 2B (see FIG. 2B), and the closed cross section forming material is formed. The lower part of 2B is formed toward the side frame 1 ((d) in the figure), and the middle part is formed in the middle direction between them (see (c) in the figure). Further, it is formed so that the cross-sectional area of the closed cross section gradually increases from the top to the bottom.
[0032]
According to this, at the joint between the strut housing 2 and the side frame 1, which is the mounting portion of the front suspension, sufficient rigidity can be ensured without increasing the plate thickness of these components themselves. Therefore, it is possible to improve the steering stability by improving the mounting rigidity of the suspension while having a structure in which the weight is reduced by avoiding an increase in the plate thickness. Further, since the closed section forming material 2B is divided into three, the form of each component for forming sections having different directions can be simplified, and press formability can be improved. Furthermore, since the joint rigidity between the side frame 1 and the strut housing 2 is increased, the effect of suppressing the displacement of the power unit 3 by the above-described mounting structure 10 can be enhanced, thereby further improving the effect of improving the steering stability performance. can do. The rigidity can be ensured by the formation of the closed cross-section as described above. The rigidity can be efficiently obtained by forming the closed cross-section so that the cross-sectional area gradually increases from the upper part to the lower part.
FIG. 6 is an explanatory diagram for explaining the overall operation of the power unit support structure according to the embodiment of the present invention (FIG. 6A is a front view, and FIG. 6B is a plan view). According to this support structure, since the power unit 3 is supported by the first bracket 12 of the mount structure 10 at a support position above the center of gravity G, the displacement of the power unit 3 due to the inclination θ can be restricted. Further, the second bracket 18 of the mount structure 10 is attached to the front surface 2A of the strut housing 2 having a closed cross section and to which the reinforcing member is fixed, and the mounting body 10A is fixed to the reinforcing member by the mounting feet 15 and 16. Since it is attached to the side frame 1, the support surface 2A facing the traveling direction of the vehicle and the side frame 1 extending in the front-rear direction of the vehicle can support the inertia force F applied to the power unit 3 during acceleration / deceleration. . Therefore, the longitudinal displacement of the power unit 3 during acceleration / deceleration can be restricted. Accordingly, even when the spring constant of the cushion rubber is set to be low in other mounting structures of the power unit 3 to improve the vibration noise performance, the displacement of the power unit 3 can be effectively regulated, and the quietness of the vehicle can be improved. And improved steering stability. Further, since displacement during acceleration / deceleration can be effectively regulated, steering stability or acceleration performance during acceleration / deceleration can be improved.
[0033]
For the front suspension housed in the strut housing 2, the rigidity of the strut housing 2, which is the mounting support, is increased, and by suppressing the displacement of the power unit during cornering, the toe change of the suspension is reduced. As a result, steering stability during cornering can be improved.
[0034]
Further, by suppressing the displacement of the power unit 3, there is no need to provide an extra space in consideration of the movement of the power unit, so that the space for the power unit storage portion (engine room) in the vehicle body can be saved. Further, the durability of the mount below the power unit can be improved.
[0035]
【The invention's effect】
Since the present invention is configured as described above, it achieves both improvement of vehicle vibration noise performance (quietness) and improvement of steering stability performance without developing an expensive engine mount. Alternatively, it is possible to provide a vehicle power unit support structure capable of improving starting performance and steering stability during cornering.
[Brief description of the drawings]
FIG. 1 is an explanatory view showing a power unit support structure according to an embodiment of the present invention.
FIG. 2 is an explanatory view showing a support structure of the entire power unit according to the embodiment of the present invention (FIG. 2 (a) is a plan view, and FIG. 2 (b) is a side view).
FIGS. 3A and 3B are explanatory views showing a mounting portion on the vehicle body side to which the mounting structure according to the embodiment of the present invention is mounted (FIG. 3A is an overall perspective view, FIG. FIG. 3C is a sectional view taken along the line YY.
FIG. 4 is an explanatory view showing a structure on the vehicle body side in the power unit support structure according to the embodiment of the present invention.
FIG. 5 is an explanatory view showing a setting state of a closed section forming material in the power unit support structure according to the embodiment of the present invention (FIG. 5 (a) is a front view (view from the front of the vehicle body), and FIG. (A) is a sectional view taken along line AA, (c) is a sectional view taken along line BB, and (d) is a sectional view taken along line CC.
FIGS. 6A and 6B are explanatory views illustrating the operation of the power unit support structure according to the embodiment of the present invention (FIG. 6A is a front view, and FIG. 6B is a plan view).
[Explanation of symbols]
1 side frame 2 strut housing 2A front surface (support surface)
2B Closed section forming material 3 Power unit 4, 5 Front cushion rubber 6 Rear cushion rubber 6A Rear cross member 7 Pitching stopper 8 Wheel apron 10 Mounting structure 10A Mount body 11 Engine side stay 12 First bracket 13 Dynamic damper 14 Cushion rubber portion 15 , 16 Mounting foot 17 Connecting portion 18 Second bracket 20-25 Screw 30, 31 Reinforcing member

Claims (7)

In a power unit support structure in which a power unit of a vehicle is supported on a vehicle body side via a cushion rubber,
A power unit support structure for a vehicle, wherein a support position above a center of gravity of the power unit and a support surface facing the traveling direction on the vehicle body side are supported by a support member. The power unit support structure for a vehicle according to claim 1, wherein the support surface is a front surface of a strut housing in which a front suspension is stored. The power unit support structure for a vehicle according to claim 2, wherein the strut housing is provided with a closed section forming member that forms a closed section in a front portion. The power unit support structure for a vehicle according to claim 3, wherein the closed section forming material is provided by being overlapped with a joint between the strut housing and the front wheel apron. The power unit support structure for a vehicle according to claim 3, wherein the closed section forming material is provided vertically and is divided into a plurality of sections. The power unit has a vertical engine mounted on a front cross member and a rear cross member connecting left and right side frames extending in the front and rear of the vehicle body,
The support member includes a first bracket attached to a mount main body and extending toward the power unit, and a second bracket attached to the mount main body and extending toward the vehicle body. The mount main body has a cushion rubber. The power unit support structure for a vehicle according to any one of claims 1 to 5, wherein the power unit support structure is mounted on one of the left and right side frames. The mount body is attached to a reinforcing member fixed to a corner in the side frame, and the second bracket is attached to a reinforcing member fixed to a closed cross section in the strut housing. The vehicle power unit support structure according to claim 6.

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