JP6259434B2 - Subframe for vehicle - Google Patents

Description

  The present invention relates to a vehicular subframe that is attached to a lower portion of an energy storage means at the rear of the vehicle.

  For example, Patent Document 1 discloses a structure in which a rear subframe is reinforced by a V-shaped support column. The vehicle front end of this column is fastened to the side frames on both sides along the vehicle width direction between the front wheel and the rear wheel, and the rear crossing portion of the column is fixed to the rear center portion of the vehicle body, Constructs a V-shape.

JP 2002-240737 A

  By the way, in recent years, with the development of automobile technology, the number and weight of equipment mounted on the vehicle has increased, and it is necessary to ensure the rigidity of the rear subframe corresponding to the increase in the weight of equipment mounted on the rear subframe. is there.

  However, in the reinforcement structure by the V-shaped support column disclosed in Patent Document 1, there is a concern whether the desired rigidity of the rear sub-frame can be ensured corresponding to the increase in the weight of the mounted device.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a vehicle subframe that can cope with an increase in the weight of a mounted device.

In order to achieve the above object, the present invention is a vehicle sub-frame that is formed separately from a vehicle body frame and is attached to the lower part of an energy source storage means at the rear of the vehicle. A front cross, which extends in the vehicle width direction of the vehicle and connects the front side and the rear side of the left side member and the rear side member of the vehicle, and forms a cross beam structure. And the vehicle subframe is connected to all of the left side member, the right side member, the front cross member, and the rear cross member that constitute the cross beam structure. comprising a that stiffener, the stiffener, the vehicle forward of the front cross member Includes a forward extending portion extending toward the vehicle front end of the front extension portion, characterized that you have connected to the body frame.

  According to the present invention, by connecting the stiffeners to all the members of the left side member, the right side member, the front cross member, and the rear cross member included in the vehicle subframe having the cross beam structure, The members are not only connected to each other, but are further connected via a stiffener. Thereby, in this invention, compared with the prior art reinforced with the V-shaped support | pillar, the rigidity when an external load is input with respect to a vehicle sub-frame can be improved. As a result, in the present invention, it is possible to obtain a vehicular subframe that can cope with an increase in the weight of the mounted device.

  According to the present invention, the vehicle front end portion of the front extending portion constituting the stiffener is connected to the body frame, for example, when an external load is input from the rear of the vehicle, the front connected to the body frame. A compressive force is applied to the extending portion. Thereby, the rigidity of the part located ahead of a vehicle rather than the subframe for vehicle frames can be improved.

  Further, according to the present invention, the stiffener includes a rearward extending portion that extends toward the rear of the vehicle with respect to the rear cross member, and the rearward extending portion is disposed at the rear of the vehicle when the vehicle is viewed from the bottom. A vehicle rear end portion extending rearward of the rear body cross frame extending along the width direction and extending rearward of the rear extension portion includes a bent portion that bends from the horizontal direction toward the vehicle upper side. It is characterized by that.

  According to the present invention, the rear cross member and the rear body cross frame are provided with a rear extension portion extending rearward of the vehicle, and the rear extension portion further includes a rear end portion and a bent portion of the vehicle. At the time of entering the parking lot, for example, the vehicle rear end portion or the bent portion can be brought into contact with the curbstone or the like before the rear wheel. As a result, in the present invention, the rear extension portion functions as a rear bumper of the vehicle subframe, and the vehicle subframe can be suitably protected from curbstones and the like.

  Furthermore, the present invention is characterized in that the stiffener does not overlap with the four corners of the cross beam structure in the vehicle vertical direction.

According to the present invention, the stiffener is disposed so as not to overlap the four-corner corners of the cross-girder structure in the vehicle vertical direction, so that the stiffener is positioned between the corners excluding the four-corner corners at the lower position of the vehicle subframe. Can be connected at an intermediate position. Thereby, the subframe for vehicles which exhibits a cross beam structure, and a stiffener can be connected with sufficient balance, and rigidity can be improved further .

  According to the present invention, it is possible to obtain a vehicular subframe that can cope with an increase in the weight of a mounted device.

1 is a side view of a schematic configuration of a vehicle rear portion of a fuel cell vehicle incorporating a rear subframe according to an embodiment of the present invention. FIG. 2 is a partially transparent perspective view of a rear portion of the fuel cell vehicle shown in FIG. 1. FIG. 3 is an enlarged perspective view of a rear subframe shown in FIG. 2. It is a perspective view of the stiffener seen from the vehicle bottom side.

Next, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.
FIG. 1 is a schematic side view of a rear portion of a fuel cell vehicle incorporating a rear subframe according to an embodiment of the present invention, and FIG. 2 is a partially transparent perspective view of the rear portion of the fuel cell vehicle shown in FIG. FIG. 3 is an enlarged perspective view of the rear subframe shown in FIG.

  In each figure, “front and rear” indicates the vehicle longitudinal direction, “left and right” indicates the vehicle lateral direction (vehicle width direction), and “vertical” indicates the vehicle vertical direction.

  As shown in FIG. 1, a fuel cell vehicle (FCV) is charged with a travel motor (not shown) disposed at the front of the vehicle, a fuel cell stack (not shown), and electric power generated in the fuel cell stack. And a large and small hydrogen tanks 4 and 6 for supplying hydrogen (fuel gas, reaction gas) to the anode of a fuel cell stack (not shown).

  The two large and small hydrogen tanks 4 and 6 are arranged in parallel along the vehicle width direction, the small hydrogen tank 4 is disposed on the front side in the vehicle front-rear direction, and the large hydrogen tank 6 is disposed on the rear side in the vehicle front-rear direction. Yes. The large hydrogen tank 6 functions as an energy source storage means, and is supported by a rear subframe 10 described later via a set of support bands (not shown).

  As shown in FIGS. 1 and 2, a rear subframe 10 (vehicle subframe) is disposed at the rear of the fuel cell vehicle FCV. The rear subframe 10 is arranged on the left and right sides of both ends in the vehicle width direction of the fuel cell vehicle FCV, respectively, and the left side member 12 and the right side member 13 extending in the vehicle front-rear direction, and the fuel cell vehicle FCV. The front cross member 14 that extends along the width direction and connects the front side of the left side member 12 and the ride side member 13, and extends along the vehicle width direction of the fuel cell vehicle FCV, and the left side member 12 And a rear cross member 16 that connects the rear portion of the ride side member 13.

  As shown in FIG. 3, the rear subframe 10 is connected to the cross beam structure in plan view by the four members (left side member 12, right side member 13, front cross member 14, rear cross member 16). Has been. The rear subframe 10 is configured separately from the body frame of the vehicle, and is attached below the large hydrogen tank 6 disposed at the rear of the vehicle.

  Further, the rear subframe 10 includes a stiffener 18 connected to each of the left side member 12, the right side member 13, the front cross member 14, and the rear cross member 16 constituting the cross beam structure.

  The left side member 12, the right side member 13, the front cross member 14, and the rear cross member 16 are hollow members having a closed cross section. For example, the upper member and the lower member made of a light metal such as aluminum are used as the upper member. They are joined together by friction stir welding from the side. In addition, you may make it couple | bond together dissimilar metals, or may couple | bond together the same kind of metals. The left side member 12 and the right side member 13 are formed to have a symmetrical shape (mirror shape) on the left side and the right side.

  Left and right rear side frames 20, 20 constituting a body frame are provided above the left side member 12 and the right side member 13 on both sides of the end portion in the vehicle width direction of the fuel cell vehicle FCV. The left and right rear side frames 20, 20 are provided so as to extend along the vehicle front-rear direction substantially parallel to the front side member 12 and the rear side member 13.

  As shown in FIG. 2, a rear body cross frame 21 that extends substantially parallel to the rear cross member 16 and connects the left and right rear side frames 20 and 20 is disposed behind the rear cross member 16. Yes. The rear body cross frame 21 constitutes a body frame.

  Both ends of the front cross member 14 along the vehicle width direction and both ends of the rear cross member 16 along the vehicle width direction are connected to the left and right rear side frames 20 and 20 via bolts and nuts, respectively. A pair of frame connecting portions 22 and 22 are provided. The left side member 12 and the right side member 13 are positioned below the frame connecting portions 22 and 22 at both ends in the vehicle front-rear direction, and the left and right rear side frames 20 and 20 are interposed via bolts and nuts. A pair of frame connecting portions 24, 24 connected to each other is provided.

  A stiffener 18 that reinforces the rear sub-frame is disposed below the rear sub-frame 10 having a cross beam structure along the vehicle vertical direction. The stiffener 18 is formed of a hollow member having a closed cross-sectional structure made of a metal material such as a steel plate.

  The stiffener 18 has a substantially rhombus shape in plan view and has an opening 25 inside. The stiffener body 26 is disposed in front of the stiffener body 26 and extends forward of the front cross member 14. 28 and a rear extending portion 30 that is disposed behind the stiffener main body 26 and extends rearward of the rear cross member 16. The stiffener main body 26, the front extending portion 28, and the rear extending portion 30 are integrally coupled to constitute the stiffener 18 as a whole.

  The stiffener body 26 includes a first suspension part 32 extending obliquely from the lower position in the center of the front cross member 14 toward both the left side member 12 and the right side member 13 in the vehicle width direction, and the rear cross member 16. And a second suspension portion 34 extending obliquely from the central lower region toward both the left side member 12 and the right side member 13 in the vehicle width direction. At the boundary between the vehicle rear end portion of the first suspension portion 32 and the vehicle front end portion of the second suspension portion 34, a coupling portion 36 that is firmly coupled by a coupling means such as welding is provided.

  The stiffener body 26 is fixed to each of the four members of the rear subframe 10 having a cross beam structure. That is, the stiffener body 26 is joined to the lower surface of the front cross member 14 via the first bracket 40 and the lower surfaces of the left side member 12 and the right side member 13 via a pair of second brackets 42 and 42. Are joined. In addition, the rear side of the stiffener main body 26 is sandwiched between the rear cross member 16 via a pair of sandwiching structure portions 46 that are spaced apart by a predetermined distance and have a flange portion 44. The pair of clamping structure portions 46 are fastened to the rear cross member 16 by bolts (not shown).

  FIG. 4 is a perspective view of the stiffener viewed from the vehicle bottom side.

  As shown in FIGS. 2 and 4, the front extension 28 extends forward of the vehicle relative to the front cross member 14, and expands from the center position of the front cross member 14 into a C shape. A vehicle front end portion 29 of the front extending portion 28 that is widened in a C-shape is connected to the left and right rear side frames 20 and 20 via bolts and nuts, respectively.

  As shown in FIG. 4, the rearward extending portion 30 is constituted by a set of strip-like plate bodies extending along the rear of the vehicle, and is more than the rear body cross frame 21 extending along the vehicle width direction. Located behind. The rear extension 30 has a vehicle rear end portion 31 that is positioned most rearward of the vehicle. The vehicle rear end portion 31 is formed of a free end that is not fixed at all, and has a bent portion 33 that is bent from the horizontal direction toward the vehicle upper side.

  As shown in FIG. 2, the stiffener 18 is provided so as not to overlap the four corners 48 a to 48 d of the rear subframe 10 having a cross beam structure in the vehicle vertical direction. That is, the stiffener 18 is connected to the rear subframe 10 at a position below the rear subframe 10 and at an intermediate position between the corners except for the four corners 48a to 48d.

  The rear sub-frame 10 according to the present embodiment is basically configured as described above. Next, the function and effect will be described.

  In this embodiment, by connecting the stiffeners 18 to all members of the left side member 12, the right side member 13, the front cross member 14, and the rear cross member 16 included in the rear subframe 10 having a cross beam structure, The members are not only connected to each other but also connected via a stiffener 18. Thereby, in this embodiment, compared with the prior art disclosed by patent document 1, the rigidity when an external load is input with respect to the rear sub-frame 10 can be improved. As a result, even when the weight of the hydrogen tank 6 mounted on the rear subframe 10 is increased, it is possible to cope with it appropriately.

  In the present embodiment, the vehicle front end portions 29 and 29 of the pair of front extending portions 28 and 28 constituting the stiffener 18 are coupled to the left and right rear side frames 20 and 20, respectively. Thus, for example, when an external load is input from the rear of the vehicle, a compressive force is applied to the front extending portions 28 and 28 connected to the left and right rear side frames 20 and 20, respectively. Thereby, when an external load is input from the rear of the vehicle, the rigidity of the portion located in front of the vehicle relative to the rear subframe 10 can be improved. In other words, since the large hydrogen tank 6 is disposed above the rear subframe 10, for example, the rigidity of the small hydrogen tank 4 located in front of the large hydrogen tank 6 can be improved.

  Further, in the present embodiment, a rear extending portion 30 that extends rearward of the vehicle from the rear cross member 16 and the rear body cross frame 21 is provided. In the present embodiment, the rearward extending portion 30 further includes a vehicle rear end portion 31 and a bent portion 33, so that, for example, when the fuel cell vehicle FCV enters the parking lot, for example, with respect to a curbstone or the like than the rear wheel. The vehicle rear end portion 31 or the bent portion 33 can be brought into contact first. As a result, in the present embodiment, the rear extension 30 functions as a rear bumper of the rear subframe 10, and the rear subframe 10 can be suitably protected from curbs.

  Furthermore, in the present embodiment, the stiffener 18 is arranged so as not to overlap the four-corner corner portions 48a to 48d of the cross-girder structure in the vehicle vertical direction, so that the stiffener 18 is positioned at the lower corner of the rear subframe 10 at the four corner angles. It can connect in the intermediate position between the corner | angular parts except the parts 48a-48d. Thereby, in this embodiment, the rear subframe 10 and the stiffener 18 which exhibit a cross-beam structure can be connected with sufficient balance, and rigidity can be improved further.

  Furthermore, in the present embodiment, the plate thickness of the front extension portion 28 and the second suspension portion 34 constituting the stiffener 18 is the first suspension portion interposed between the front extension portion 28 and the second suspension portion 34. The thickness of the portion 32 is larger. Thereby, in this embodiment, for example, when vibration is input to the rear subframe 10 via a rear suspension device (not shown), this vibration can be suppressed by a change in the plate thickness.

6 Hydrogen tank (energy source storage means)
10 Rear subframe (vehicle subframe)
12 Left side member 13 Right side member 14 Front cross member 16 Rear cross member 18 Stiffener 20 Rear side frame (body frame)
21 Rear body cross frame (body frame)
DESCRIPTION OF SYMBOLS 28 Front extension part 29 Vehicle front end part 30 Back extension part 31 Vehicle rear end part 33 Bending part 48a-48d Four corner part FCV Fuel cell vehicle (vehicle)

Claims (3)

A vehicle sub-frame that is configured separately from the vehicle body frame and is attached below the energy source storage means at the rear of the vehicle,
A left side member and a right side member extending in the longitudinal direction of the vehicle;
A front cross member and a rear cross member that extend in the vehicle width direction of the vehicle and that form a cross beam structure by connecting the front side and the rear side of the left side member and the right side member, respectively,
With
The vehicle subframe is:
A stiffener connected to each of the left side member, the right side member, the front cross member, and the rear cross member constituting the cross beam structure,
The stiffener is
A front extending portion extending toward the front of the vehicle from the front cross member,
The vehicle front end of the front extension portion, the sub-frame for a vehicle characterized that you have connected to the body frame. The vehicle subframe according to claim 1 ,
The stiffener is
A rear extension portion extending rearward of the vehicle from the rear cross member;
The rear extension portion extends rearward from the rear body cross frame extending along the vehicle width direction behind the vehicle when the vehicle is viewed from the bottom.
A vehicle subframe, wherein a rearward end portion of the rearward extending portion extending rearward of the vehicle includes a bent portion that is bent from the horizontal direction toward the upper side of the vehicle. In the vehicle subframe according to claim 1 or 2 ,
The vehicle sub-frame, wherein the stiffener does not overlap with the four corners of the cross beam structure in the vehicle vertical direction.

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