JP4835990B2 - Mounting bracket mounting structure - Google Patents

Description

  The present invention relates to a mount device for supporting a power unit including an engine, a transmission, and the like on a vehicle body in a vehicle such as an automobile, and relates to a mount bracket mounting structure for mounting a mount bracket to a vehicle body side member.

Generally, in a vehicle such as an automobile, a power unit including an engine, a transmission, and the like is supported on the vehicle body by a plurality of mounts including a cushioning material such as rubber, and vibration transmitted from the engine or the like to the vehicle body is reduced. is doing. In the conventional mounting structure, a cross member is provided under the floor of the vehicle, and a mount bracket for mounting a power unit including an engine and a transmission on the vehicle body is attached to the cross member. Here, the mount bracket is fastened and fixed to the lower surface of the cross member by bolts. The mount includes a cylindrical mount body integrally provided on a bracket attached to the power unit, a cushioning material made of rubber or the like fitted in the mount body, and a bolt or the like disposed through the cushioning material. And a bush for inserting the shaft. A support shaft such as a bolt is inserted into the support shaft hole of the mount bracket attached to the vehicle body and the bush of the mount, and the power unit is pivotally supported on the vehicle body.
Patent Document 1 discloses an example of a mounting structure for supporting a rear mount of a driving device (engine, transmission, differential) on a vehicle body. In the technique disclosed in Patent Document 1, a suspension plate is fixed to the lower surface of a cross member that connects left and right side rails, and a rear mount of a drive device is supported by a shaft that is supported at both ends by the suspension plate. is there.
Japanese Patent Laid-Open No. 2001-239843

In the conventional mounting structure, the mount bracket is fastened and fixed to the cross member by bolts. Therefore, when the mount bracket is fastened and fixed to the cross member by bolts, surface treatment such as plating or painting on the mount bracket alone is required. In addition to the necessity, it takes time for assembly to the vehicle body on the production line, and there is a concern that productivity will deteriorate. In addition, it is necessary to ensure the rigidity of a single mounting bracket such as increasing the plate thickness. Furthermore, if the plate thickness is increased, the unit price of the parts becomes higher because the processing such as bending becomes difficult in addition to the unit price of the material.
As a countermeasure for these, a method of fixing the mount bracket to the member by spot welding can be considered. When the mount bracket is fixed to the member by spot welding, it becomes possible to perform surface treatment such as plating or painting on the mount bracket at the same time as the surface treatment of the member, thereby improving productivity. Furthermore, since it is only necessary to ensure the rigidity in cooperation with the parts fixed by welding, it is not necessary to ensure the rigidity of the mount bracket alone, and the mounting bracket can be easily created.
However, in the case of fixing by spot welding, reliability such as durability may be reduced as compared with the case of fixing by bolting, and the design thereof requires caution. In particular, the spot welded part is strong against the force in the shear direction (force in the direction parallel to the joint surface) but weak against the force in the peel direction (force in the direction perpendicular to the joint surface). If it acts on the welded part, the mounting bracket may peel off.

  On the other hand, in the conventional mounting structure in Patent Document 1, the suspension plate is fixed to the lower surface of the cross member, and the rear mount of the drive device is supported by the shaft supported at both ends by the suspension plate. The rear mount protrudes, and the arrangement requires a height in the vertical direction of the vehicle, and the space under the floor of the vehicle is limited. Therefore, the degree of freedom of arrangement of the driving device or the suspension device is small.

  The present invention has been made in view of such circumstances, and the purpose thereof is to remove the spot welded portion of the mount bracket by the input from the mount even if spot welding is used in consideration of productivity. It is an object to provide a mounting structure for a mounting bracket that can be prevented and has improved durability.

  To achieve the above object, the present invention provides a mounting structure for a mount bracket that supports a mount fixed to a drive device or a suspension device by welding and fixing to a member having a closed cross section of a vehicle body. The side surface is provided with a concave portion that is constituted by an upper surface and a vertical wall and is open to the side and downward. The mount bracket is disposed in the concave portion, and the mount bracket is provided on the upper surface and the vertical wall of the concave portion. It is spot-welded and spot-welded to the upper side surface of the member extending upward from the end of the upper surface opposite to the vertical wall of the recess.

  Further, in the present invention, the mount bracket is disposed on both sides of the mount, and the first and second supports extending in the vertical direction are formed with support shaft holes through which the support shafts supporting the mount are respectively inserted. A wall, a connecting portion connecting the upper ends of the first and second support walls, an upper flange bent upward from an end portion of the connecting portion, and an end portion of the supporting wall from the end portion of the supporting wall. A vertical flange that is bent along the vertical wall, the connecting portion is overlaid on the upper surface of the concave portion, the vertical flange is overlaid on the vertical wall of the concave portion, and the upper flange is on the upper side surface Are overlapped and each spot welded.

  In the present invention, the bottom surface of the member extending in the direction opposite to the concave portion from the lower end of the vertical wall of the concave portion is bent along the bottom surface of the member from the lower ends of the first and second support walls. The lower flange is spot welded.

  Further, in the present invention, the support shaft is disposed below the connecting portion, and the support shaft hole is on the upper flange side with respect to the center between the vertical flange and the upper flange in the horizontal direction. It is formed in the position shifted to.

In the mounting structure of the mount bracket according to the first aspect of the present invention, by providing the concave portion on the side surface of the member, the weld surface of the mount bracket is increased, and the assembly strength with the member is increased. Durability). Further, since the mount bracket is arranged and welded in the concave portion of the member, it is possible to reduce the amount of downward projection of the mount bracket from the member as compared with the conventional assembly structure using the suspension plate. Therefore, the degree of freedom of arrangement is improved as compared with the arrangement of the driving device or the suspension device in the conventional assembly structure using the suspension plate. Also, because the mount bracket is spot welded to the upper surface and vertical wall of the recess and spot welded to the upper side surface of the member, the mount bracket can be projected sideways while being mounted to the side of the member The mounting bracket can be firmly fixed without being in a state.
Furthermore, since it is only necessary to ensure rigidity in cooperation with the members, the strength of the mount bracket alone can be set relatively low, and the mount bracket can be manufactured by setting the plate thickness of the mount bracket low. It becomes easy and the cost can be reduced.

  Furthermore, in the mount bracket that receives a downward force mainly to suspend the mount, the joint portion (substantially horizontal joint surface) with the upper surface of the recess of the member has a direction to peel off the spot welded joint surface. As the vertical force acts, peeling may occur. However, in the mounting structure of the mount bracket according to the first aspect of the present invention, the mount bracket is spot-welded not only to the upper surface of the recess, but also to the vertical wall of the recess and the upper side surface of the member. As a result, stress can be prevented from concentrating on the edge (edge) of the spot welded portion between the upper surface of the recess and the member, and the shearing direction is applied to the downward force, and the weld strength of the spot welding is high. It is possible to receive a downward force at the joint portion of the surface extending vertically (the vertical wall of the recess and the upper side surface of the member), and the strength and durability of the welding are improved.

  In the mounting structure of the mount bracket according to the second aspect of the present invention, the upper ends of the first and second support walls are connected to provide a connecting portion, so that the rigidity of the first and second support walls is improved. In addition, the accuracy of the position between the support walls can be easily secured. Moreover, since the upper flange bent upward from the end of the connecting portion of the mount bracket is provided, the rigidity of the connecting portion can be improved by the bent shape. The mount bracket according to claim 2 has a structure that can be bent and formed from a single sheet metal member, and can be easily formed.

  In the mounting structure of the mount bracket according to the third aspect of the present invention, the flange bent along the bottom surface of the member from the lower ends of the first and second support walls is spot welded to the bottom surface of the member. It is possible to prevent the movement in the peeling direction on the welded joint surface of the vertical wall, and to improve the reliability (durability and strength) of the welded joint. In addition, since a plurality of welded portions are provided on the vertical wall of the recess and the bottom surface of the member, the rigidity of the mount bracket is not limited to the force in the peeling direction on the weld joint surface but also the force that deforms the mount bracket. And the deformation of the mounting bracket can be prevented.

  In the mounting structure of the mount bracket according to the fourth aspect of the present invention, the support shaft (bolt) is located below the connecting portion of the mount bracket (that is, located between the vertical flange and the upper flange in the horizontal direction). Therefore, even when a force in the peeling direction is applied to the end portion of the connecting portion of the mount bracket by a force input from the mount, the upper flange can efficiently prevent the peeling from the member. Further, since the support shaft is disposed at a position shifted in the horizontal direction to the upper flange side from the center between the vertical flange and the upper flange, the force in the peeling direction generated at the upper end portion of the upper flange is relatively small. And the upper flange can be prevented from peeling off from the member. In addition, the mount support shaft is located in the recess of the member, and the mount bracket that supports the mount is spot welded to the upper surface and vertical wall of the recess and is not cantilevered. The durability of the welded portion of the mount bracket is improved.

  An embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a perspective view of a mount bracket 1 mounted under the floor in the approximate center of the vehicle as viewed from the lower front, and the vertical and horizontal directions in the drawing are the vertical vehicle width direction of the vehicle. 2 is an arrow view from the X direction in FIG. 1, and FIG. 3 is a cross-sectional view taken along the line AA in FIG. 1. 4 is a cross-sectional view taken along the line BB in FIG. 1 when the mount 4 is attached.

In the embodiment of the mounting structure of the mount bracket according to the present invention, a cross member 2 is provided under the floor of the vehicle, and a mount 4 of a power unit (not shown) composed of an engine and a transmission is mounted on the cross member 2. A mounting bracket 1 that is supported on the vehicle body is attached. The mount 4 has a cylindrical mount body 4a integrally provided on a bracket attached to the power unit, and has a cushioning material 4b made of rubber or the like fitted in the mount body 4a, and penetrates the cushioning material 4b. And a bush 4d for inserting a support shaft 4c such as a bolt.
1, the mount 4 is arranged in a suspended state with respect to the mount bracket 1. That is, the mount bracket 1 to which the present invention is applied does not support the mount 4 from below.

The cross member 2 is disposed below the floor of the vehicle so as to extend in the left-right direction (vehicle width direction) of the vehicle. Specifically, the cross member 2 is a sheet metal member formed in a cross-sectional hat shape, and includes a bottom surface 2b, side surfaces 2e and 2f formed by bending upward from front and rear ends of the bottom surface, and an upper end of the side surface. And flanges 2c and 2d formed by bending in opposite directions. Further, the cross member 2 has a closed cross-section by welding the front and rear flanges 2c and 2d to the lower surface of the floor panel 3. On the front side surface 2e of the cross member 2, a concave portion 10 is formed by bulging a part of the upper portion forward. As shown in FIG. 2, the recess 10 is formed in a staircase shape, and in order from the bottom, the bottom 2 b, the vertical wall 10 b rising upward from the front end of the bottom 2 b, and the upper end of the vertical wall 10 b And an upper side surface 2a rising upward from the front end of the upper surface 10a.
A flange 2 c that is bent along the floor panel 3 is formed at the upper end of the upper side surface 2 a of the cross member 2, and is spot-welded to the lower surface of the floor panel 3. Further, on the bottom surface 2b of the cross member 2, a rear side surface 2f is formed to rise from the rear end of the bottom surface 2b. A flange 2d bent backward along the floor panel 3 is formed at the upper end of the side surface 2f, and is spot-welded to the lower surface of the floor panel 3.
Here, the bottom surface 2b of the cross member 2 and the top surface 10a of the recess 10 are formed of substantially horizontal surfaces having different heights, and the vertical wall 10b of the recess 10 and the upper side surface 2a of the cross member 2 are positioned in the horizontal direction. It consists of different vertical surfaces.

The mount bracket 1 is bent and formed from a single sheet metal member. The mount bracket 1 is arranged on the left and right sides of the mount body 4a, and is provided on the upper and lower sides of the vehicle in which support shaft holes 1e through which the support shafts 4c inserted through the bushes 4d pass are formed. Support walls 1f and 1g extending in the direction are provided. Further, the mount bracket 1 extends from the rear ends of the left and right support walls 1f and 1g in the vehicle left-right direction along the vertical wall 10b of the recess. A bent vertical flange 1b, a lower flange 1d extending from the lower ends of the left and right support walls 1f, 1g in the vehicle left-right direction and extending along the bottom surface 2b of the cross member 2, and a connecting portion 1c And an upper flange 1a bent upward from the front end. Further, a reinforcing flange 1h formed by bending is formed at the front ends of the support walls 1f, 1g from the upper flange 1a to the lower flange 1d, and the front ends and lower ends of the support walls 1f, 1g are reinforced with the lower flange 1d. The flange 1h is reinforced. The support shaft hole 1e is formed at a position shifted in the horizontal direction from the center between the vertical flange 1b and the upper flange 1a toward the upper flange 1a.
The upper flange 1a is formed in a surface that is substantially perpendicular to the surface of the connecting portion 1c, and the vertical flange 1b is also formed in a surface that is substantially perpendicular to the surface of the connecting portion 1c. . The lower flange 1d is also formed on a surface that is substantially perpendicular to the surface of the vertical flange 1b.

Next, the mounting procedure of the mounting structure of the mount bracket according to the embodiment of the present invention will be described.
First, the mount bracket 1 is disposed in the recess 10 of the cross member 2, the connecting portion 1 c of the mount bracket 1 is overlapped on the upper surface 10 a of the recess 10, and the vertical flange 1 b of the mount bracket 1 is overlapped on the vertical wall 10 b of the recess 10. The upper flange 1 a is overlapped with the upper side surface 2 a of the cross member 2, and the lower flange 1 d is overlapped with the bottom surface 2 b of the cross member 2. Next, the overlapped portions are spot welded. Here, in this embodiment, spot welding is performed at two points on the upper flange 1b, three points on the connecting portion 1c, two left and right points on the vertical flange 1b, and one left and right point on the lower flange 1d. Thereafter, the flanges 2c and 2d of the cross member 2 are spot-welded with being superimposed on the lower surface of the floor panel 3.
The mount 4 is attached to the mount bracket 1 by arranging a bush 4d between the support walls 1f and 1g of the mount bracket 1, and the support shaft hole 1e of the mount bracket 1 attached to the vehicle body side and the bush of the mount 4. This is done by inserting a support shaft 4c such as a bolt into 4d. Then, the screw portion of the support shaft 4 c protruding from the mount bracket 1 is fastened and fixed with a nut, and the power unit is pivotally supported on the vehicle body via the mount bracket 1.
Thus, the mounting work of the mount bracket 1 to the cross member 2 and the mounting work of the mount 4 to the mount bracket 1 are completed.

  In the mounting structure of the mount bracket according to the embodiment of the present invention, the welded portions of the vertical flange 1b and the lower flange 1d, which are lower than the welded portions of the upper flange 1a and the connecting portion 1c above the mount bracket 1, are supported. It is formed so as to spread in the vehicle width direction with respect to the walls 1f and 1g, and a wide welding interval is ensured in the vehicle width direction as a whole. And the spot welding position of the mount bracket 1 is arrange | positioned so that the space | interval of the left-right direction of a welding position may become large centering on the mount 4 as it goes below, seeing from the vehicle front direction. For this reason, the mount 4 is mounted in a state of being suspended downward as in this embodiment, and receives not only downward force due to the weight of the power unit but also vibrations in various directions as the vehicle travels. The mount bracket 1 can effectively receive a force (mainly a force applied downward) from the mount 4 and can support the mount 4.

That is, with respect to the force that drops off the mounting bracket 1 received from the mount 4, the spot welding portion between the upper flange 1 a and the upper side surface 2 a of the cross member 2 in the shear direction of spot welding, and the vertical flange 1 b Spot welded portions of the recess 10 with the vertical wall 10b are arranged at positions on both sides (front and rear direction and left and right direction) of the mount 4 so as to receive the force from the mount 4 effectively. Furthermore, since the joint surface which becomes the shear direction of the said spot welding is arrange | positioned at the both sides of the spot welding part of the connection part 1c used as the peeling direction of spot welding, and the upper surface 10a of the recessed part 10, the connection part 1c and the recessed part 10 of FIG. The stress in the peeling direction is not concentrated on the spot welded portion with the upper surface 10a. As a result, the spot welded portion between the cross member 2 and the mount bracket 1 can be prevented from being peeled off, and the mounting strength of the mount bracket 1 is increased, so that the durability is improved.
With respect to the force to drop (peel) the mounting bracket 1 forward, the spot welding portion between the connecting portion 1c and the upper surface 10a of the recess 10 in the shear direction of spot welding, the lower flange 1d and the cross member 2 Spot welded portions with the bottom surface 2 b are disposed at positions on both sides of the mount 4 in the vertical direction. Furthermore, since the joint surface which becomes the shear direction of the said spot welding is arrange | positioned in the up-down direction both sides of the spot welding part of the vertical flange 1b used as the peeling direction of spot welding, and the vertical wall 10b of the recessed part 10, the vertical flange 1b and The stress in the peeling direction is not concentrated on the spot welded portion of the recess 10 with the vertical wall 10b. As a result, the spot welded portion between the cross member 2 and the mount bracket 1 can be prevented from being peeled off, and the mounting strength of the mount bracket 1 is increased, so that the durability is improved.

  As shown as 1 e (support shaft hole) in FIG. 2, the support shaft 4 c that supports the mount 4 is located in the recess 10. Specifically, the height of the support shaft 4c is located between the bottom surface 2b of the cross member 2 and the top surface 10a of the recess 10, and the positions of the support shaft 4c in the vehicle front-rear direction are the upper flange 1a and the vertical flange 1b. It is arrange | positioned in the position which shifted | deviated to the upper flange 1a side rather than the center between. Thereby, excessive force does not concentrate on the spot welded portion between the upper flange 1a and the upper side surface 2a and the spot welded portion between the lower flange 1d and the bottom surface 2b, which are welded portions at the upper and lower ends of the mount bracket 1. Therefore, the durability of the welded portion of the mount bracket 1 is improved.

  Further, as shown in FIG. 2, since the mount bracket 1 is arranged and welded to the recess 10 of the cross member 2, the distance h from the floor panel 3 to the mount 4 can be set short. Since the protrusion amount of the mount 4 downward from the cross member 2 can be reduced and the necessary space under the floor for the mount 4 can be reduced, the floor of the vehicle can be lowered to widen the indoor space. In addition, the degree of freedom of arrangement (layout) is improved as compared with the arrangement of the driving device or the suspension device in the mounting structure using the conventional suspension plate.

Further, in the mount bracket 1, each weld joint surface is positioned in a substantially right angle direction with respect to the adjacent weld joint surface, and spot welding is performed, so even if a force in the peeling direction acts on a certain weld joint surface, It is possible to prevent spot welding from being peeled off by the weld joint surface. That is, stress can be prevented from concentrating on the end portion (edge) of the spot welded portion on the welded joint surface (the upper surface 10a of the concave portion and the vertical wall 10b of the concave portion) sandwiched between the other weld joint surfaces from both sides. Accordingly, the entire spot welded portion receives a force input from the mount 4, and the spot welded portion of the mount bracket 1 can be prevented from peeling off from the cross member 2, and the welding strength is ensured. .
With the above configuration, since the durability of the welded joint surface of the mount bracket 1 is improved, it is possible to use spot welding, which is highly advantageous in terms of production efficiency, for mounting the mount bracket 1 to the cross member 2. Yes.
The present invention is particularly effective when the mount bracket 1 is not disposed (placed) on the cross member 2 as in the present embodiment (when it is disadvantageous for the coupling durability of the mount bracket 1). It is.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications and changes can be made based on the technical idea of the present invention.

  In the present embodiment, as described above, the recess 10 is provided by bulging a part above the side surface 2e of the cross member 2, but the corners of the side surface and the bottom surface of the cross member are within the cross section of the cross member. It is also possible to form a recess by recessing in the direction.

  In this embodiment, as shown in FIG. 1, spot welding is performed at two points on the upper flange 1b, three points on the connecting portion 1c, two left and right points on the vertical flange 1b, and one left and right point on the lower flange 1d. However, the number of spot welds is not limited to this, and can be changed according to the shape of the mount bracket.

  In this embodiment, the mounting structure of the mounting bracket of the present invention is applied to a mount that supports a power unit under the floor, but it can also be applied to a mount of an engine or the like under a dash panel.

  Further, the mounting structure of the mount bracket of the present invention can be applied to fixing a suspension arm, a shock absorber, and the like.

It is a perspective view of the mount bracket concerning one embodiment of the present invention. It is an arrow view from the X direction of FIG. It is the sectional view on the AA line of FIG. It is the BB sectional view taken on the line of FIG. 1 when an engine mount is attached.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mount bracket 1a Upper flange 1b Vertical flange 1c Connection part 1d Lower flange 1e Support shaft hole 1f, 1g Support wall 1h Reinforcement flange 2 Cross member 2a Cross member upper side surface 2b Cross member bottom face 2c Cross member front end flange 2d flange at the rear end of the cross member 2e front side surface of the cross member 2f rear side surface of the cross member 3 floor panel 4 mount 4a mount body 4b cushioning material 4c support shaft 4d bush 10 cross member recess 10a cross member recess top surface 10b cross Vertical wall of member recess

Claims (4)

A mounting bracket mounting structure for supporting a mount fixed to a drive device or a suspension device by welding and fixing to a member configured in a closed cross section of a vehicle body,
On the side surface of the member, a concave portion that is constituted by an upper surface and a vertical wall and that opens to the side and below is provided.
The mounting bracket is disposed in the recess,
The mount bracket is spot welded to the upper surface and vertical wall of the recess and spot welded to the upper side surface of the member extending upward from the end of the upper surface opposite to the vertical wall of the recess. Mounting bracket mounting structure that is characteristic. The mounting bracket is
First and second support walls which are arranged on both sides of the mount and extend in the vertical direction in which support shaft holes into which support shafts supporting the mount are inserted are formed;
A connecting portion connecting upper ends of the first and second support walls;
An upper flange bent upward from the end of the connecting portion;
A vertical flange bent along the vertical wall of the recess from the end of the support wall;
Superimposing the connecting portion on the upper surface of the recess,
The vertical flange is overlaid on the vertical wall of the recess,
The mounting structure for a mounting bracket according to claim 1, wherein the upper flange is overlapped with the upper side surface and each is spot welded.   A lower flange bent from the lower ends of the first and second support walls along the bottom surface of the member is spot welded to the bottom surface of the member extending from the lower end of the vertical wall of the concave portion in the direction opposite to the concave portion. The mounting structure of the mounting bracket according to claim 2, wherein the mounting bracket is mounted.   The support shaft is disposed below the connecting portion, and the support shaft hole is formed at a position shifted in the horizontal direction from the center between the vertical flange and the upper flange toward the upper flange. The mounting bracket mounting structure according to claim 2, wherein the mounting bracket mounting structure is provided.

Images