JPH1016818A - Body structure - Google Patents

Abstract

(57) [Summary] [Problem] To restrict axial vibration of components of a mount without adding a stopper. The vehicle body structure includes a power unit (17) disposed in an engine room of the vehicle body, a groove-shaped center member (22) forming a frame of the vehicle body, and an inner cylinder and an outer cylinder (29). And a mount 28 formed by combining them with an elastic body. The mount 28 is arranged in the internal space of the center member 22. The outer cylinder 29 of the mount 28 is fixed to the engine 15 of the power unit 17 by the power unit side bracket 33, and the upper and lower ends of the inner cylinder are fixed to the opposing upper wall 25 and bottom wall 27 of the center member 22. In this structure, when vibration in the axial direction (vertical direction) is applied to the mount 28 from the power unit 17, the outer cylinder 29 and the elastic body 32 try to move in the same direction, but the movement is caused by the upper wall 25 or the bottom wall 25. It is regulated by the wall 27.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle body structure to which a power unit is attached.

[0002]

2. Description of the Related Art In a general vehicle, a power unit formed by connecting an engine and a transmission is disposed in an engine room at a front portion of a vehicle body. The power unit is attached to a member forming a skeleton of a vehicle body via a mount. For example, JP-A-7-8161
No. 7 discloses a "vehicle body front structure" in which mounts are arranged in side members provided on both left and right sides in an engine room. In this technique, as shown in FIG. 8, a through hole 52 is formed in a side wall 51a of a side member 51, and a vehicle body side bracket 53 is inserted into the through hole 52 and fixed to the side wall 51a. Further, a flange 55 is formed on the power unit 54, and a power unit side bracket 56 is attached thereto.

The mount 57 is for elastically supporting the power unit 54 on the vehicle body, and includes an outer cylinder 59 and an inner cylinder 61 extending in the horizontal direction, and an elastic body 62 connecting the both 59, 61. . Outer cylinder 5 of this mount 57
9 is fitted to the vehicle body side bracket 53 and is fixed to the side member 51 by bolts or the like (not shown). A connection bolt 64 is inserted through the power unit side bracket 56 and the inner cylinder 61, and a nut 65 is screwed to the end thereof. These connecting bolts 64 and nuts 65
The inner cylinder 61 and the power unit side bracket 56
And are connected.

[0004]

However, in the technique disclosed in the above-mentioned publication, the inner cylinder 61 which is a component of the mount 57 is not disclosed.
Nothing restricts the movement of the elastic body 62 in the axial direction (the left-right direction in FIG. 8). Therefore, when vibration in the axial direction is applied to the mount 57 from the power unit 54, in order to restrict the movement of the inner cylinder 61 and the like in that direction,
As shown by a two-dot chain line in FIG. 8, it is necessary to newly provide a stopper 66 in the inner cylinder 61. Such a problem also occurs when the mount is housed in the center member, the outer cylinder is connected to the center member, and the inner cylinder is connected to the power unit.

The present invention has been made in view of the above-mentioned circumstances, and has as its object the purpose of adding a stopper without adding a stopper.
The purpose is to regulate the axial vibration of the components of the mount.

[0006]

According to a first aspect of the present invention, there is provided a power unit disposed in an engine room of a vehicle body, comprising: a power unit disposed in an engine room of the vehicle body; A member having an inner cylinder and an outer cylinder, and a mount formed by connecting these two cylinders with an elastic body. The mount is arranged in the member, and the outer cylinder is fixed to the power unit. In addition, both ends of the inner cylinder are fixed to inner walls facing the members.

In the first aspect of the invention, when vibration is applied from the power unit to the mount in the axial direction, the outer cylinder and the elastic body tend to move in the same direction. One is regulated by hitting the inner wall of the member. In other words, the inner wall facing the member also functions as a stopper.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, the mount connects the power unit and the member substantially below the center of gravity of the power unit, and a connection point of the member with the mount. Extends along a tangential direction of a circle centered on the rotation axis of the engine of the power unit.

In the second aspect of the present invention, when the power unit and the member are connected by a mount substantially below the center of gravity of the power unit, the power unit operates and moves in the tangential direction of a circle centered on the rotation axis of the engine. A heading force occurs. This force is transmitted to the member via the mount. On the other hand, from the vehicle body side, a force acts on the member in a direction opposite to the tangential direction. Here, the extending direction of the member receiving the force in both directions coincides with the tangential direction and the opposite direction. For this reason, a force is applied to the member in the direction in which the member has the highest rigidity, that is, the direction in which the member extends, and almost no vertical force for bending the member is applied. Therefore, it is not necessary to increase the rigidity of the member in the bending direction.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the first and second inventions will be described below with reference to FIGS.

As shown in FIG. 2, a front portion (left side portion in FIG. 2) of the vehicle body 11 is provided with a rectangular frame-shaped body frame 12 for supporting a hood, a fender panel and the like. Body frame 12
Has an engine room 13 in which a power unit 17 including an engine 15 and a transmission 16 is disposed. Engine 15
A plurality of cylinders 14 arranged along the width direction of the vehicle body 11 (substantially left-right direction in FIG. 2), a rotating shaft (crankshaft) 23 extending in the same direction and rotating in the direction of arrow A in FIG. It has. The transmission 16 is disposed on the right side of the engine 15 and is drivingly connected to the rotating shaft 23.
As described above, the power unit 17 is disposed laterally with respect to the vehicle body 11.

The body 11 is a member of the skeleton.
Suspension member 18, a pair of left and right side members 1
9, 19, a front cross member 21 and a center member 22. The suspension member 18 is for supporting a suspension arm (an arm for controlling the movement of the wheel). The member 18 is disposed at the rear of the engine room 13 and has both side members 19, 19.
Has been concluded. The two side members 19, 19 support the power unit 17 from both left and right sides thereof, and function as a cushioning member when an impact is applied from the front of the vehicle body 11. The two side members 19 are arranged on both left and right sides of the engine room 13 and extend in the front-rear direction of the vehicle body 11 in parallel with each other. Each side member 1
The rear ends of the members 9 and 19 are fixed to the body frame of the vehicle body 11 by welding. The front end portions of the side members 19, 19 protrude forward from the main body frame 12. The front cross member 21 functions as a buffer member similarly to the side members 19 and 19 described above, and is disposed on the back side of a bumper (not shown). The front cross member 21 extends in the width direction of the vehicle body 11, and is fixed to the side members 19 at both end portions thereof.

The center member 22 reinforces the body frame 12 and supports the power unit 17 from below. The center member 22 is a power unit 17
It is arranged below. The front end of the center member 22 is fixed to the main body frame 12 by a fastening member (not shown) such as a bolt, and the rear end is also fixed to the suspension member 18 by a fastening member (not shown). As shown in FIG. 1, the center member 22 includes an upper wall portion 25, a side wall portion 26, and a bottom wall portion 27, and has a groove shape that is open on a side surface as a whole. The upper wall portion 25 and the bottom wall portion 27 constitute a pair of inner walls facing each other.

The power unit 17 includes a mount 28
The elastic member is elastically supported by the center member 22.
More specifically, the mount 28 includes an outer cylinder 29 and an inner cylinder 31 disposed in the outer cylinder 29 as shown in FIGS.
And an elastic body 3 such as rubber for connecting the outer cylinder 29 and the inner cylinder 31
2 and a power unit side bracket 33. The inner cylinder 31, the outer cylinder 29, and the elastic body 32 are accommodated in the center member 22 at a position immediately below the center of gravity 24 of the power unit 17 in such a manner that their axes 34 extend in the vertical direction. Power unit side bracket 33
Is composed of a flat mounting portion 35 and a connecting portion 36 connecting the mounting portion 35 and the outer cylinder 29. A plurality of holes 37 are formed in the mounting portion 35, and the mount 28 is fastened to the engine 15 by a plurality of bolts 38 inserted into these holes 37.

In the upper wall portion 25 and the bottom wall portion 27,
Holes 39 are provided at positions corresponding to the upper and lower ends of the inner cylinder 31 respectively.
Is open. These holes 39, 39 and the inner cylinder 31
A bolt 41 is inserted through the nut, and a nut 42 is screwed onto the bolt 41. Both ends of the inner cylinder 31 are fastened to the opposing upper wall portion 25 and bottom wall portion 27 of the center member 22 by these bolts 41 and nuts 42. Thus, the mount 28 is located at the center of gravity 2 of the power unit 17.
4, the power unit 17 and the center member 22 are connected.

Further, as shown in FIG. 3, at least a connecting portion (accommodating portion) of the center member 22 with the mount 28 is in a tangential direction of a circle 43 centered on the rotating shaft (crankshaft) 23 of the engine 15. Extending. Here, the entire center member 22 extends horizontally in the front-rear direction.

According to the present embodiment having the above-described structure, when an axial (vertical) vibration is applied from the power unit 17 to the mount 28 by an external force, the outer cylinder 29 and the elastic body 32 move in the same direction. The movement is restricted by at least one of the outer cylinder 29 and the elastic body 32 hitting the upper wall portion 25 or the bottom wall portion 27 of the center member 22. In other words, the upper wall portion 25 and the bottom wall portion 27 constitute a part of the center member 22 and also function as a stopper. Therefore, unlike the related art, it is not necessary to newly provide a stopper, and the number of components can be reduced accordingly.

The power unit 17 and the center member 22 are located below the center of gravity 24 of the power unit 17.
Are connected by the mount 28, the rotating shaft 23 is driven by the engine torque of the power unit 17.
Is generated in the direction of the tangent of the circle 43 centered at. This force is transmitted to the center member 22 via the mount 28. On the other hand, as the reaction, a force F in the direction opposite to the tangential direction acts on the center member 22 from the vehicle body 11 side. Here, the tangential direction and the opposite direction,
The extending direction of the center member 22 that receives the force in both directions matches. For this reason, a force is applied to the center member 22 in the direction in which the center member 22 extends (the front-rear direction), which is the direction having the highest rigidity, and almost no vertical force for bending the center member 22 is applied. Absent. Therefore, it is not necessary to increase the rigidity of the center member 22 in the bending direction, and the center member 22 can be reduced in weight. As described above, the support structure of the power unit 17 using the mount 28 described above is less likely to cause bending vibration of the center member 22 and is advantageous in securing the strength of the center member 22 in the same direction.

This embodiment has the following features in addition to the items described above. (A) Focusing on the fact that the center member 22 is formed in a groove shape, most of the mount 28 is accommodated in the internal space of the center member 22, so that the internal space of the center member 22 which is normally an empty space is provided. Can be used effectively. There is no need to secure a dedicated space for installing the mount 28 in the engine room 13.

(B) When the power unit is supported on the vehicle body, a bracket is usually fixed to the power unit, the bracket is fixed to the vehicle body, and a mount is interposed between these brackets. In the present embodiment, the upper wall portion 25 and the bottom wall portion 27 of the center member 22 also function as a bracket on the vehicle body side. Therefore, the bracket on the vehicle body side can be omitted, the number of parts can be reduced correspondingly, and the weight can be reduced.

The present invention can be embodied in another embodiment shown below. (1) The mount 28 is the center of gravity 24 of the power unit 17
Even when the power unit 17 and the center member 22 are connected to each other at a position slightly shifted forward or backward from immediately below, the same effect as in the above embodiment can be obtained. In this case, the connection point of the center member 22 with the mount 28 and the vicinity thereof are extended along the tangential direction of a circle 43 centered on the rotation shaft 23 of the engine 15 as shown in FIG. It is desirable to have a shape. Note that reference numeral 46 in the figure denotes a virtual line extending through the center of gravity 24 and extending in the vertical direction.

(2) From the viewpoint of achieving the object of the present invention, the mount 28 may be accommodated not only in the center member 22 but also in another member. (3) In the above-described embodiment, the groove-shaped center member 22 has been described as an example, but the cylindrical member 4 as shown in FIG.
4 may be used. However, in this case, it is necessary to provide an opening 45 in the member 44 in order to position the power unit side bracket 33 outside the member 44.

While the embodiments of the present invention have been described above, technical ideas other than the claims that can be grasped from each embodiment will be described below together with their effects. (A) In the vehicle body structure according to claim 2, the engine is arranged so that a rotation axis thereof extends in a width direction of the vehicle body, and the member extends in a front-rear direction of the vehicle body below a center of gravity of a power unit. Body structure that is the center member that supports the power unit.

With this configuration, a force in the front-rear direction, which is the direction in which the rigidity of the center member is highest, is applied from the power unit or the vehicle body to the center member. The force for bending the center member up and down is not easily applied. Therefore, it is not necessary to increase the rigidity of the center member in the vertical direction.

[0025]

According to the first aspect of the present invention, the opposing inner walls of the member restrict the axial movement of the components of the mount, so that it is not necessary to newly provide a stopper, and the number of components can be reduced. Can be.

According to the second aspect, in addition to the effect of the first aspect, it is not necessary to increase the rigidity of the member in the bending direction, and the weight can be reduced accordingly.

[Brief description of the drawings]

FIG. 1 is a partial perspective view showing a positional relationship among a power unit, a center member, and a mount.

FIG. 2 is a schematic diagram showing a configuration inside an engine room.

FIG. 3 is a schematic side view showing a positional relationship among a power unit, a center member, and a mount.

FIG. 4 is an exploded perspective view of a connection part of the power unit with a center member.

FIG. 5 is a sectional view showing a state in which both ends of an inner cylinder of the mount are fastened to a center member.

FIG. 6 is a schematic side view showing another embodiment in which a power unit and a center member are connected by a mount at a position shifted rearward from immediately below a center of gravity.

FIG. 7 is a partial perspective view showing another embodiment using a cylindrical member.

FIG. 8 is a partial sectional view showing a conventional technique.

[Explanation of symbols]

11 ... body, 13 ... engine room, 15 ... engine,
17 power unit, 22 center member, 23 rotation axis, 24 center of gravity, 28 mount, 29 outer cylinder, 31
... inner cylinder, 32 ... elastic body, 43 ... circle.

Claims (2)

[Claims] 1. A power unit disposed in an engine room of a vehicle body, a groove-shaped or cylindrical member forming a skeleton of the vehicle body, and an inner cylinder and an outer cylinder, both of which are formed of elastic bodies. And a mount that is connected to the power unit.
A body structure in which both ends of the inner cylinder are fixed to the inner walls facing the members. 2. The mount connects the power unit and a member substantially below the center of gravity of the power unit,
2. The vehicle body structure according to claim 1, wherein a connection point between the member and the mount extends along a tangential direction of a circle centered on a rotation axis of an engine of the power unit. 3.