JP2015231781A - Front sub-frame - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a number of components when a crash can is attached to a front end part of a side member of a front sub-frame, and attach the front side of the side member with respect to the front side of a front side frame with high rigidity.SOLUTION: A sub-frame comprises: a side member 40; and a front side mount member 60 for attaching a front side of the side member 40 to a front side of a front side frame. The front side mount member 60 is formed of a plate material which is molded so as to have a cross section opened to the front side. On a front part of the front side mount member 60, attachment plate parts 64, 65 for attachment of a crash can 70, are integrated and molded.

Description

  The present invention relates to a front subframe provided at a front portion of a vehicle.

  Conventionally, a front sub-frame that supports a suspension arm below a front side frame is sometimes provided at the front of a vehicle (see, for example, Patent Document 1). The front subframe of Patent Document 1 includes a pair of side members extending in the front-rear direction, a rear cross member that connects the rear sides of the side members, and a front cross member that connects the front sides of the side members. Pipe-shaped front and rear mounting members are attached to the front and rear sides of the side members, respectively. The front and rear mounting members are fixed to the front side frame. Further, a crash can is attached to the front end portion of the side member via an attachment plate extending in the vertical direction.

JP2013-203243A

  By the way, assuming a frontal collision of a vehicle, there is a demand for suppressing damage to the front side frame and the front subframe by compressing and deforming only the crash can at the time of a light collision. For this purpose, it is necessary to firmly attach the front side of the side member of the front sub-frame to the front side frame to suppress deformation of the side member at the time of a light collision.

  In addition, when a vehicle travels, force is input from the suspension arm to the front subframe, but there is also a demand to increase the rigidity of attaching the front subframe to the front side frame.

  Furthermore, in Patent Document 1, a mounting plate must be provided in order to attach the crash can to the front end portion of the side member of the front subframe, which increases the number of parts.

  The present invention has been made in view of the above points, and an object of the present invention is to reduce the number of parts when attaching a crash can to the front end portion of the side member of the front subframe, and further to the front side of the side member. Is to be attached to the front side of the front side frame with high rigidity.

  In order to achieve the above object, in the present invention, the front mounting member of the front subframe is formed of a plate material having a cross section that opens to the front side, and the mounting plate portion of the crash can is integrally formed with the front mounting member. I tried to do it.

The first invention is
In the front subframe disposed on the lower side of the left and right front side frames provided at the front of the vehicle body,
The front sub-frame includes a cross member that extends in the left-right direction of the vehicle body, a side member that extends from the both sides of the vehicle body in the left-right direction of the vehicle body, and a front mounting member for attaching the front side of the side member to the front side of the front side frame. And
The front mount member is composed of a plate material formed to have a cross section that opens to the front side of the vehicle, and a mounting plate portion for attaching the crash can is integrally formed on the front portion of the front mount member. It is characterized by that.

  According to this configuration, by forming the plate material so as to have a cross section that opens to the front side of the vehicle, a cross-sectional shape with high rigidity can be obtained as compared with the case of forming a simple flat plate shape or the like. As a result, the front side of the side member is attached to the front side of the front side frame with high rigidity, so that, for example, during a light collision, only the crash can can be compressed and deformed to suppress deformation of the side member. In addition, it is possible to sufficiently support the input from the suspension arm to the front subframe when the vehicle is traveling.

  Further, since the mounting plate portion for attaching the crash can is integrally formed with the front mounting member, a separate member is not necessary when attaching the crash can, and the number of parts can be reduced.

According to a second invention, in the first invention,
On the front side of the side member, a notch that opens to the front end surface of the side member is formed,
The front mount member is welded to a peripheral portion of the notch in a state of being inserted into the notch of the side member.

  According to this configuration, since the welded portion between the front mount member and the side member is widely secured, the attachment rigidity of the front mount member is further increased.

According to a third invention, in the first or second invention,
The front mounting member extends in the vertical direction,
The mounting plate portion extends in the vehicle width direction from the front portion of the front mounting member and extends in the vertical direction.

  According to this configuration, since the attachment plate portion extending in the vehicle width direction extends in the vertical direction, the attachment plate portion functions as a rib of the front mount member, and the front mount member is reinforced.

According to a fourth invention, in any one of the first to third inventions,
The front mount member includes a rear plate portion that extends in the vehicle width direction on the vehicle rear side of the front mount member, and a side plate portion that extends from both edges of the rear plate portion in the vehicle width direction to the vehicle front side. It has a character-like cross section.

  According to this configuration, the side plate portion extends in the front-rear direction when a rearward external force is applied from the front side of the vehicle to the lower side in the state where the upper side of the front mounting member is fixed to the front side frame, for example, during a light collision. Therefore, high proof stress is generated. As a result, the front side of the side member is attached to the front side of the front side frame with higher rigidity.

  According to the first aspect of the invention, since the front mount member of the front subframe is constituted by the plate material formed so as to have a cross section that opens to the front side, the front side of the side member is highly rigid with respect to the front side of the front side frame. In addition, since the mounting plate portion of the crash can is integrally formed with the front mounting member, the number of parts can be reduced.

  According to the second invention, since the front mount member is inserted into the cutout portion of the side member and welded to the peripheral portion of the cutout portion, the attachment rigidity of the front mount member can be further increased.

  According to the third aspect of the invention, the mounting plate portion extends in the vehicle width direction from the front portion of the front mounting member and extends in the vertical direction, so that the front mounting member can be reinforced by the mounting plate portion.

  According to the fourth invention, the front mount member has a substantially U-shaped cross section having a rear plate portion extending in the vehicle width direction and a side plate portion extending toward the vehicle front side. High yield strength can be generated, and the front side of the side member can be attached to the front side of the front side frame with higher rigidity.

It is a perspective view of the front subframe concerning an embodiment. It is a side view which shows schematic structure of the vehicle front part provided with the front sub-frame. It is a perspective view which expands and shows the front side of the left side frame of the state which attached the crash can. FIG. 4 is a view corresponding to FIG. 3 with the crash can removed. FIG. 4 is a view corresponding to FIG. 3 with the front mount member removed.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the following description of the preferred embodiment is merely illustrative in nature, and is not intended to limit the present invention, its application, or its use.

  FIG. 1 is a perspective view showing a front subframe 10 according to an embodiment of the present invention. The vehicle provided with the front subframe 10 is a passenger car including an engine room E on the front side of the vehicle and a passenger compartment R on the rear side of the engine room E as shown in FIG. A dash panel 2 extending in the vertical direction is provided between the engine room E and the vehicle compartment R of the vehicle. A floor panel 3 constituting the floor surface of the passenger compartment R is connected to the lower edge of the dash panel 2. A floor tunnel (not shown) that bulges upward is formed at the center in the left-right direction of the floor panel 3. Further, side sills (not shown) extending in the front-rear direction are provided on both left and right edges of the floor panel 3.

  In the description of this embodiment, the front side of the vehicle body is simply referred to as “front”, the rear side of the vehicle body is simply referred to as “rear”, the left side of the vehicle body is simply referred to as “left”, and the right side of the vehicle body is simply referred to as “right”. To do.

  The vehicle is provided with left and right front side frames 4 (only one is shown) and a front subframe 10. The left and right front side frames 4 are provided at intervals in the left-right direction of the vehicle body, and an engine room E is provided therebetween. The left front side frame 4 extends in the front-rear direction on the left side of the vehicle body, and the right front side frame 4 extends in the front-rear direction on the right side of the vehicle body.

  The left and right front side frames 4 have substantially the same shape in a side view. The rear end portion of the front side frame 4 is continuous with the front end portion of the side sill. The front side frame 4 extends obliquely upward from the vicinity of the front edge of the floor panel 3 toward the front side, and then bends and extends to the front side in the horizontal direction. A crash can 5 is provided on the front side of the front side frame 4. A bumper reinforcement (not shown) extending in the left-right direction is attached to the front portion of the crash can 5. Although not shown, the front wheels are disposed on the outside of the vehicle body in the front-rear direction intermediate portion of the front side frame 4.

  Next, the structure of the front subframe 10 will be described. The front subframe 10 is configured to support a suspension arm (both not shown), and is disposed below the front side frame 4 and attached to the front side frame 4.

  As shown in FIG. 1, the front subframe 10 is configured by combining steel plates, and includes a cross member 20, left and right tower portions 30, 30, left and right side members 40, 40, A connecting member 50 that connects the front sides of the members 40, 40, left and right front mounting members 60, 60, and left and right crush cans 70, 70 are provided.

  The cross member 20 includes a member main body 21 that extends in the left-right direction, and rear attachment portions 22, 22 that extend left and right from the left and right sides of the member main body 21. Each rear attachment portion 22 is connected to the rear side of the front side frame 4 from below. Further, a support portion of the suspension lower arm is swingably attached to the rear attachment portion 22 of the cross member 20.

  The left and right tower portions 30, 30 extend upward from the front side of the member main body 21 of the cross member 20. The tower 30 on the left side extends so as to be located on the left side as it goes upward, and its upper end is connected to the middle part in the front-rear direction of the front side frame 4 from below. The right tower portion 30 extends to the right as it goes upward, and is connected to the front side frame 4 in the same manner as the left tower portion 30.

  The left side member 40 is connected to the left side of the member main body 21 of the cross member 20, and extends from the connecting portion toward the front side. In the side view shown in FIG. 2, the left side member 40 is curved so that the front side is positioned higher than the rear side. Further, as shown in FIG. 1, the rear side of the left side member 40 is curved so as to be positioned to the right as compared with the front side.

  As shown in FIGS. 3 to 5, the left side member 40 is configured by combining an upper member 41 and a lower member 42. Both the upper member 41 and the lower member 42 are formed by press forming a steel plate. The upper member 41 includes an upper plate portion 41a and side plate portions 41b and 41b extending downward from both left and right edges of the upper plate portion 41a. Have. The lower member 42 includes a lower plate portion 42a facing the upper plate portion 41a, and side plate portions 42b and 42b extending upward from both left and right edges of the lower plate portion 42a. It has a cross-sectional shape that is molded and opens upward.

  In the state where the open side of the upper member 41 and the open side of the lower member 42 are combined, the side plate portions 41b and 41b of the upper member 41 and the side plate portions 42b and 42b of the lower member 42 are in the thickness direction. The upper member 41 and the lower member 42 are integrated with each other.

  On the front side of the upper plate portion 41 a of the upper member 41, an upper cutout portion 41 c is formed by cutting out so as to open to the front end surface of the side member 40. The left and right side edges of the upper notch 41c extend in the front-rear direction, and the rear edge of the upper notch 41c extends in the left-right direction continuously to the rear ends of the left and right side edges. That is, the upper notch 41c has a substantially U-shape that opens to the front side.

  In addition, a lower notch portion 42c that opens to the front end surface of the side member 40 is formed on the front side of the lower plate portion 42a of the lower member 42 in the same manner as the upper plate portion 41a. The shape of the edge of the lower notch 42c is substantially the same as the shape of the edge of the upper notch 41c.

  The right side member 40 is symmetrical to the left side member 40 and has the same structure.

  The front mount member 60 disposed on the left side is formed of a steel plate press-formed so as to have a cross section that opens to the front side. The vertical dimension of the front mounting member 60 is set to be longer than the vertical dimension of the front side of the side member 40. The upper side of the front mounting member 60 protrudes upward from the upper plate portion 41a of the side member 40, and this upper side is the front side. It can be attached to the front side of the side frame 4 from below.

  The front mount member 60 includes a rear plate portion 61 extending in the left-right direction (vehicle width direction) on the rear side of the front mount member 60, and a side plate portion 62 extending frontward from both lateral edges of the rear plate portion 61. And a substantially U-shaped cross section. The rear plate portion 61 extends in the vertical direction, and the width thereof is set to be approximately the same as the width of the upper notch portion 41c and the lower notch portion 42c. The dimension in the front-rear direction of the side plate part 62 is set to be approximately the same as the dimension in the front-rear direction of the upper notch 41c and the lower notch 42c.

  The lower side of the front edge portion of the side plate portion 62 extends substantially in the vertical direction along the front end surface of the side member 40, while the upper side of the front edge portion tilts rearward so as to be positioned rearward as it goes upward. ing. A left mounting plate 64 for mounting the crash can 70 is integrally formed on the front edge of the left side plate 62. The left mounting plate portion 64 extends from the front edge portion of the side plate portion 62 to the left side, and extends in the vertical direction so as to cover both the upper and lower end portions of the front edge portion. The left mounting plate portion 64 and the side plate portion 62 are substantially orthogonal in a plan view. The left side of the left mounting plate portion 64 extends so as to be located on the left side of the left side surface of the side member 40.

  A fastening plate portion 64 a to which the crash can 70 is fastened is provided at the lower portion of the left mounting plate portion 64. The fastening plate portion 64a extends to the left side, and a bolt insertion hole 64b through which a bolt B as a fastening member is inserted is formed in the vicinity of the center portion so as to penetrate in the front-rear direction. Further, an abutting portion 64c with which the crash can 70 abuts is provided at the middle in the vertical direction of the left mounting plate portion 64.

  The upper side of the left edge portion of the left mounting plate portion 64 above the contact portion 64c is inclined so as to be positioned on the right side as it goes upward. Therefore, the width of the upper side of the left mounting plate portion 64 becomes narrower as it goes upward.

  A right attachment plate portion 65 for attaching the crash can 70 is integrally formed at the front edge portion of the right side plate portion 62. The right mounting plate portion 65 extends from the front edge portion of the side plate portion 62 to the right side, and extends in the vertical direction so as to cover both the upper and lower end portions of the front edge portion. In the plan view, the right mounting plate portion 65 and the side plate portion 62 are substantially orthogonal. The right side of the right mounting plate portion 65 extends so as to be located on the right side of the right side surface of the side member 40.

  A fastening plate portion 65 a to which the crash can 70 is fastened is provided at the middle portion in the vertical direction of the right mounting plate portion 65. The fastening plate portion 65a extends to the right side, and a bolt insertion hole 65b through which the bolt B is inserted is formed in the vicinity of the center portion so as to penetrate in the front-rear direction. Further, a contact portion 65c with which the crash can 70 contacts is provided at the lower portion of the right mounting plate portion 65.

  The upper side of the right edge portion of the right mounting plate portion 65 with respect to the fastening plate portion 65a is inclined so as to be positioned on the left side as it goes upward. Therefore, the width of the upper side of the right mounting plate portion 65 becomes narrower as it goes upward.

  An upper plate portion 66 is provided at the upper end portion of the front mounting member 60. The upper plate portion 66 extends substantially horizontally along the lower surface of the front side frame 4, and is integrally formed with one side plate portion 62. An upper edge portion of the other side plate portion 62 and an upper edge portion of the rear plate portion 61 are welded to the lower surface of the upper plate portion 66, and both the side plate portions 62 and the rear plate portion are interposed via the upper plate portion 66. The upper side of 61 is integrated.

  A through hole 66 a is formed in a substantially central portion of the upper plate portion 66. A fastening member for fastening the front mount member 60 to the front side frame 4 is inserted into the through hole 66a.

  The lower side of the front mounting member 60 disposed on the left side is welded to the peripheral portions of the cutout portions 41c and 42c while being inserted into the upper and lower cutout portions 41c and 42c of the side member 40. . As a result, both the parts separated in the vertical direction on the lower side of the front mounting member 60 are welded to the side member 40, so that the mounting rigidity of the front mounting material 60 to the side member 40 can be increased. Further, since the left and right side surfaces and the rear surface of the front mounting member 60 can be welded to the side member 40, a wide welded portion can be secured.

  In a state where the front mounting member 60 is attached to the side member 40, the rear surface of the left mounting plate portion 64 and the rear surface of the right mounting plate portion 65 are in contact with the left and right sides of the front end surface of the side member 40.

  The front mounting member 60 disposed on the right side has the same structure as that disposed on the left side.

  The crash can 70 is formed so as to protrude forward from the front mounting member 60, and includes an upper half 71 made of a steel plate, a lower half 72, and an attachment member 73. Yes. The upper half 71 is opened downward, and the lower half 72 is opened upward. The open side of the upper half 71 and the open side of the lower half 72 are welded and integrated. The attachment member 73 is disposed at the rear end portion of the crash can 70 so as to extend in the vertical direction, and is welded to the upper half 71 and the lower half 72.

  Fastening plate portions 73 a and 73 a fastened to the fastening plate portions 64 a and 65 a of the front mounting member 60 are formed on the attachment member 73 so as to extend in the left-right direction. The fastening plate portions 73a and 73a of the crash can 70 are formed with insertion holes 73b and 73b through which the bolts B are inserted.

  As described above, according to this embodiment, the front mount member 60 is configured by the plate material formed to have a cross section that opens to the front side. Thereby, since it becomes a cross-sectional shape with which high rigidity is obtained compared with the case where it comprises, for example with simple flat plate shape etc., the front side of side member 40 can be attached to the front side of front side frame 4 with high rigidity. Therefore, for example, at the time of a light collision, only the crash can 70 can be compressed and deformed to suppress deformation of the side member 40. Further, it is possible to sufficiently support the input from the suspension arm to the front subframe 10 when the vehicle is traveling.

  Furthermore, since the attachment plate portions 64 and 65 for attaching the crash can 70 are integrally formed with the front mounting member 60, no separate member is required when attaching the crash can 70, and the number of parts can be reduced.

  Further, since the front mount member 60 is inserted into the upper and lower cutout portions 41c and 42c of the side member 40 and welded to the peripheral portions of the cutout portions 41c and 42c, the mounting rigidity of the front mount member 60 is further increased. be able to.

  Further, since the mounting plate portions 64 and 65 extend in the left-right direction from the front portion of the front mounting member 60 and extend in the vertical direction, the front mounting member 60 can be reinforced by the mounting plate portions 64 and 65. .

  Further, since the front mount member 60 has a substantially U-shaped cross section including a rear plate portion 61 extending in the left-right direction and side plate portions 62, 62 extending toward the front side, the front mount member 60 has a high yield strength at the time of a light collision. And the front side of the side member 40 can be attached to the front side of the front side frame 4 with higher rigidity.

  The above-described embodiment is merely an example in all respects and should not be interpreted in a limited manner. Further, all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

  As described above, the front subframe according to the present invention can be applied to, for example, a passenger car.

4 Front side frame 10 Front subframe 20 Cross member 40 Side members 41c, 42c Notch 60 Front mount member 61 Rear plate 62 Side plate 64, 65 Mounting plate 70 Crash can

Claims (4)

In the front subframe disposed on the lower side of the left and right front side frames provided at the front of the vehicle body,
The front sub-frame includes a cross member that extends in the left-right direction of the vehicle body, a side member that extends from the both sides of the vehicle body in the left-right direction of the vehicle body, and a front mounting member for attaching the front side of the side member to the front side of the front side frame. And
The front mount member is composed of a plate material formed to have a cross section that opens to the front side of the vehicle, and a mounting plate portion for attaching the crash can is integrally formed on the front portion of the front mount member. Front subframe characterized by that. The front subframe according to claim 1,
On the front side of the side member, a notch that opens to the front end surface of the side member is formed,
The front subframe is characterized in that the front mounting member is welded to a peripheral portion of the cutout portion in a state of being inserted into the cutout portion of the side member. In the front subframe according to claim 1 or 2,
The front mounting member extends in the vertical direction,
The front sub-frame, wherein the mounting plate portion extends in the vehicle width direction from the front portion of the front mounting member and extends in the vertical direction. In the front sub-frame according to any one of claims 1 to 3,
The front mount member includes a rear plate portion that extends in the vehicle width direction on the vehicle rear side of the front mount member, and a side plate portion that extends from both edges of the rear plate portion in the vehicle width direction to the vehicle front side. A front sub-frame having a character-like cross section.

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