JP5377043B2 - Car body rear structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To distribute and transmit a collision energy to the entire part of a vehicle body upon rear end collision if the rear end collision of a vehicle occurs. <P>SOLUTION: This vehicle body rear structure 10 includes a center cross member 21 and a middle cross member 22 which connect the intermediate parts and the rear end parts of side sills 13, 14 in the vehicle lateral direction, respectively, right and left rear frames 15, 16 extending from the rear ends of the side sills 13, 14 rearward, respectively, a floor panel 18 which is installed between the right and left side sills 13, 14 and which constitutes the floor of a cabin, and a spare tire pan 19 installed between the right and left rear frames 15, 16. A torsion beam 17 is disposed along the middle cross member 22, the front ends of center frames 35, 36 extending in the longitudinal direction along the spare tire pan 19 are positioned close to the rear of the torsion beam 17, and the rear end of a floor frame (center tunnel) 45 connected to the center cross member 21 is positioned close to the forward of the torsion beam 17. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a vehicle body rear structure used in a vehicle having a torsion beam type rear suspension.

As a rear body structure, a structure in which transmission of collision energy is considered at the time of rear collision of the vehicle is known.
This type of vehicle body rear structure has been appropriately designed so as to ensure a sufficient collision stroke and disperse the collision energy to the vehicle body frame.
As such a vehicle body rear part structure, a structure in which a reinforcing frame (center frame) is provided in the front-rear direction of the vehicle body in a spare tire storage part is known (see, for example, Patent Document 1).

  The rear structure of the vehicle body of Patent Document 1 includes a rear frame (rear side member) that extends from the rear ends of a pair of side sills in the longitudinal direction of the vehicle body, a rear connection member that connects the rear ends of these rear frames, and the rear connection member. A rear cross member installed on a pair of rear frames, a rear center frame installed on a rear cross member and a rear connecting member, and having a lower surface inclined forwardly. The spare tire is disposed in contact with the lower surface of the rear center frame while being disposed below the floor panel of the vehicle body.

However, in the rear structure of the vehicle body of Patent Document 1, an input load at the time of a rear collision is transmitted from the rear connecting member to the rear cross member and from the rear frame to the side sill, but is provided between the left and right side sills. There is a problem that the load cannot be distributed and transmitted to the floor panel constituting the floor.
Therefore, the strength of the rear frame and the side sill must be increased in order to be able to withstand a large input load at the time of a rear collision, and the weight of the vehicle body cannot be reduced.

JP 2002-362426 A

The present invention provides a vehicle body rear structure capable of distributing and transmitting the collision energy at the time of rear collision to the entire vehicle body and preventing deformation of the vehicle body when a rear collision occurs in the vehicle. Is an issue.
It is another object of the present invention to provide a vehicle body rear structure that can withstand a large input load during a rear collision.

The invention according to claim 1 includes left and right side sills extending to the left and right of the floor panel, a center cross member and a middle cross member respectively connecting the middle and rear end portions of these side sills in the vehicle width direction, Vehicle body rear structure having left and right rear frames extending rearward from the rear end of each side sill, a floor panel that is passed between the left and right side sill to form a floor of the passenger compartment, and a spare tire pan between the left and right rear frames The rear end of the floor frame is arranged with a torsion beam along the middle cross member, the front end of the center frame extending in the front-rear direction along the spare tire pan close to the torsion beam, and connected to the center cross member in front of the torsion beam. was close, having a first engaging member at the rear end of the floor frame, the first Has an extension portion connected to the rear end to the middle cross member extending upwardly of the engaging member, the extension is characterized in that it engaged with all the movable range of the torsion beam.

  The invention according to claim 2 is characterized in that the torsion beam has an open cross section in which at least one of the torsion beams is open, and has a cross-section collapse preventing member that increases the strength of the torsion beam at the opening of the open cross section.

The invention according to claim 3 is characterized in that the center frame has a second engaging member that engages with the torsion beam at the front end, and can be engaged with the entire movable range of the torsion beam.

The present invention has the following effects.
In the invention according to claim 1, left and right side sills extending front and rear are provided on the left and right sides of the floor panel, and the middle and rear end portions of these side sills are connected by the center cross member and the middle cross member in the vehicle width direction, respectively. The left and right rear frames are extended rearward from the rear ends of the left and right side sills, the floor panel constituting the floor of the passenger compartment is passed between the left and right side sills, and spare tire pans are arranged between the left and right rear frames.
A torsion beam is arranged along the middle cross member, the front end of the center frame extending in the front-rear direction along the spare tire pan is brought close to the rear of the torsion beam, and the rear end of the floor frame connected to the center cross member is arranged in front of the torsion beam. The input load at the time of rear collision is distributed not only to the left and right side sills but also from the floor frame to the center cross member. Thereby, the side sill can be reduced in weight. Or the deformation | transformation of a floor panel when the input load at the time of a rear surface collision is large can be prevented.
Furthermore, the load can be transmitted by sandwiching the torsion beam. Therefore, it can cope with a large load exceeding the load resistance of the torsion beam.
In the first aspect of the invention, the rear end of the floor frame has the first engagement member, and the rear end of the first engagement member has an extension portion that extends upward and connects to the middle cross member. And since this extension part can be engaged with the whole movable range of the torsion beam, even when the torsion beam moves up and down, the load can be transmitted from the floor frame to the middle cross member. As a result, it is possible to further improve the load transmission efficiency.

In the invention according to claim 2, the torsion beam has an open cross section in which at least one of the torsion beams is open, and the opening of the open cross section has a cross-section collapse preventing member that increases the strength of the torsion beam. It can be closed with a cross-section collapse preventing member. Thereby, while increasing the intensity | strength of a torsion beam, it can prevent that an opening part opens with an impact. As a result, load transmission efficiency can be improved.
In addition, it is possible to minimize the deterioration in ride comfort and the increase in weight associated with improving the strength of the torsion beam itself.

In the invention according to claim 3 , since the second engaging member that engages the torsion beam is provided at the front end of the center frame and can be engaged with the entire movable range of the torsion beam, The two engaging members are crushed and engaged. As a result, the load can be transmitted from the center frame to the torsion beam regardless of the cross-sectional shape of the torsion beam.

It is the perspective view seen from the bottom part of the vehicle body rear part structure of 1st Example which concerns on this invention. It is a perspective view which shows the principal part of the vehicle body rear part structure shown by FIG. It is a bottom view of the vehicle body rear part structure shown by FIG. FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. FIG. 5 is a sectional view taken along line 5-5 of FIG. It is principal part sectional drawing of the vehicle body rear part structure shown by FIG. FIG. 2 is a comparative study diagram comparing the actions of the vehicle body rear structure shown in FIG. 1. FIG. 2 is an operation explanatory diagram of a vehicle body rear structure shown in FIG. 1. It is a perspective view which shows the principal part of the vehicle body rear part structure of 2nd Example which concerns on this invention. FIG. 10 is a sectional view taken along line 10-10 in FIG. 9;

  Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.

  As shown in FIGS. 1 to 6, the vehicle body rear structure 10 includes left and right side sills 13 and 14 that extend in the longitudinal direction of the vehicle body, and left and right rear sills that extend rearward from the rear ends of these side sills 13 and 14. Frames 15, 16, torsion beams 17 that are swingably supported by front portions 15 a, 16 a of these rear frames 15, 16, a floor panel 18 supported by left and right side sills 13, 14, and left and right rear frames 15 , 16, a spare tire pan 19 supported by the left and right side sills 13, 14, a center cross member 21 that supports the floor panel 18, and left and right rear frames 15, 16 front portions 15 a, 16 a It is passed to the middle cross member 22 that supports the rear part of the panel 18 and the front part of the spare tire pan 19 and the left and right rear frames 15 and 16. The rear cross member 23 that supports the rear portion of the spare tire pan 19, the rear bumper beam 27 joined to the left and right rear frames 15, 16 via extensions 25, 26, and the center cross of the floor panel 18 are formed. A floor frame (center tunnel) 45 passed to the member 21 and the middle cross member 22 in the longitudinal direction of the vehicle body, and extended from the rear of the middle cross member 22 to the rear cross member 23 and the upper surface of the bottom 49 of the spare tire pan 19 49a includes left and right center frames 35 and 36 provided in the longitudinal direction of the vehicle body, and a spare tire 47 accommodated in the recess 48 of the spare tire pan 19.

The center frames 35 and 36 are load transmission members. The left and right side sills 13 and 14 are linearly arranged in the longitudinal direction of the vehicle body.
The left and right rear frames 15 and 16 have front portions 15a and 16a that are curved inwardly of the vehicle body and are curved and formed above the vehicle body. Further, the rear portions 15b and 16b are formed linearly.

  The torsion beam 17 is a component of a rear suspension (not shown), and is formed in a substantially H shape in plan view. Further, the torsion beam 17 has an open cross section in which one (front) is open, and a central portion 17a of the torsion beam 17 has a cross-section collapse preventing member 37 that increases the strength of the torsion beam 17 in the opening 17b of the open cross section. .

  Since the cross-section collapse preventing member 37 is provided only in the central portion 17a of the torsion beam 17, an increase in the weight of the torsion beam 17 can be minimized.

  The floor panel 18 has a front floor 28 formed at the front of the vehicle body 11, a center floor 29 formed at the center of the vehicle body 11, and a spare tire pan 19 formed at the rear of the vehicle body 11.

  The front floor 28 has a center tunnel 45 formed at the center of the vehicle body and in the longitudinal direction of the vehicle body. The center tunnel 45 has a front end coupled to the center cross member 21 and a rear end having first engagement members 41 and 42 described later. Respectively. Further, the front floor 28 is reinforced with a tunnel stiffener 46.

  The tunnel stiffener 46 includes a stiffener body 51 and left and right reinforcing members 52 and 53 provided on the stiffener body 51.

  The spare tire pan 19 is a member formed in a concave shape toward the lower side of the vehicle body, and as described above, the center frames 35 and 36 are disposed on the upper surface 49a of the bottom 49 of the spare tire pan 19 and are described later. The engaging member 43 is disposed on the front wall 19 a of the spare tire pan 19.

  The floor frame (center tunnel) 45 has first engagement members 41 and 42 at the rear ends. The first engaging members 41, 42 have extension portions 41 a, 42 a that extend upward at the rear end and are connected to the middle cross member 22.

  The first engagement members 41 and 42 are disposed opposite to a second engagement member 43 described later with the torsion beam 17 interposed therebetween. The first engaging members 41 and 42 are members that are crushed by a collision load and engage with the front of the torsion beam 17, and the front ends thereof are coupled to the center tunnel 45 and the tunnel stiffener 46. The rear end shape is set to a shape that can maintain an appropriate gap even if the torsion beam 17 swings in the vehicle longitudinal direction. With respect to the vertical direction of the vehicle, the vertical height is set to be extended so that the torsion beam 17 can be reliably hit at the time of rear-end collision even if the torsion beam 17 swings up and down. That is, the extension portions 41a and 42a have a predetermined height.

  Further, the ends of the extension portions 41 a and 42 a of the first engaging members 41 and 42 are coupled to the cross section of the middle cross member 22.

The center frames 35 and 36 include a second engagement member 43 that is engaged with the torsion beam 17 on the front side. The second engagement member 43 is provided on the front wall 19 a (rear wall of the center floor 29) of the spare tire pan 19 that constitutes the center portion of the floor panel 18.
The rear ends 35b and 36b of the center frames 35 and 36 are coupled to the rear cross member 23 extending in the vehicle body width direction.

  In other words, the second engagement member 43 is disposed with the front ends 35 a and 36 a of the center frames 35 and 36 and the front wall 19 a of the spare tire pan 19 interposed therebetween. The front wall 19a is also the rear wall of the center floor 29.

  The second engagement member 43 is a member that is crushed by a collision load and engages the rear of the torsion beam 17 and is configured to maintain an appropriate gap even if the torsion beam 17 swings in the vehicle front-rear direction. Is done. With respect to the vehicle width direction, the width is set to connect the center frames 35 and 36 as shown in FIGS. As for the vehicle vertical direction, the vertical height is set so that the torsion beam 17 can be reliably hit at the time of a rear collision even if the torsion beam 17 swings up and down.

  In the vehicle body rear structure 10, left and right side sills 13, 14 extending in the front-rear direction are provided on the left and right of the floor panel 18. The left and right rear frames 15 and 16 are extended rearward from the rear ends of the left and right side sills 13 and 14, respectively, and a floor panel 18 constituting the floor of the passenger compartment is formed between the left and right side sills 13 and 14. The spare tire pan 19 is disposed between the left and right rear frames 15 and 16.

  The torsion beam 17 is disposed along the middle cross member 22, and the front ends 35 a and 36 a of the center frames 35 and 36 extending in the front-rear direction along the spare tire pan 19 are brought close to the rear of the torsion beam 17. The rear end of the floor frame (center tunnel) 45 connected to the cross member 21 is brought close to the rear frame, and the input load at the time of rear collision is applied not only from the left and right side sills 13 and 14 but also from the floor frame (center tunnel) 45 to the center cross member 21. Also disperse. Thereby, the side sills 13 and 14 can be reduced in weight. Or the deformation | transformation of the floor panel 18 when the input load at the time of a rear surface collision is large can be prevented.

  Furthermore, the load can be transmitted by sandwiching the torsion beam 17. Accordingly, it is possible to cope with a large load exceeding the load resistance of the torsion beam 17. Further, it is possible to minimize the deterioration in ride comfort and the increase in weight associated with improving the strength of the torsion beam 17 itself.

  The floor frame (center tunnel) 45 has first engagement members 41 and 42 at the rear ends, and extends upward to the rear ends of the first engagement members 41 and 42 and is connected to the middle cross member 22. Extension portions 41 a and 42 a are provided, and these extension portions 41 a and 42 a can be engaged with the entire movable range of the torsion beam 17. Therefore, even when the torsion beam 17 moves up and down, the load can be transmitted from the floor frame (center tunnel) 45 to the middle cross member 22. As a result, it is possible to further improve the load transmission efficiency.

  The center frames 35, 36 have a second engagement member 43 that engages the torsion beam 17 at the front end and can engage with the entire movable range of the torsion beam 17. The two engaging members are crushed and engaged. As a result, the load can be transmitted from the center frames 35 and 36 to the torsion beam 17 regardless of the cross-sectional shape of the torsion beam 17.

  FIG. 7A shows the behavior of the torsion beam 17 of the vehicle body rear structure 10 of the first embodiment, and FIGS. 7B and 7C show the behavior of the torsion beam 101 of the vehicle body rear structure 100 of the comparative example. Indicated.

  In FIG. 7A, in the vehicle body rear structure 10 according to the first embodiment, the torsion beam 17 has an open cross section in which at least one of the torsion beams 17 is open, and the cross section that increases the strength of the torsion beam 17 in the opening 17b of the open cross section. A prevention member 37 is provided. Accordingly, even when the torsion beam 17 moves forward or upward as indicated by arrows a1 and a2, the opening 17b can be brought into contact with the extensions 41a and 42a of the first engagement members 41 and 42 without opening. . Thereby, the load can be smoothly transmitted from the torsion beam 17 to the first engagement members 41 and 42.

  Even when the torsion beam 17 moves below the extensions 41a and 42a of the first engagement members 41 and 42 as indicated by the arrow a3, the opened opening 17b is blocked by the cross-section collapse preventing member 37. The opening 17b can be prevented from being inserted into the extension portions 41a and 42a.

  In FIG. 7B, in the vehicle body rear structure 100 of the comparative example, the opening 101b of the torsion beam 101 remains open. Therefore, when the torsion beam 101 moves forward as indicated by the arrow b1, the opening 101b opens. Therefore, smooth load transmission cannot be performed.

  In FIG. 7C, in the vehicle body rear structure 100 of the comparative example, when the torsion beam 101 moves downward as indicated by an arrow c1, the opening 101b may be fitted into the first engaging member 102.

  That is, in the vehicle body rear structure 10 according to the first embodiment, the torsion beam 17 has an open cross section in which at least one of the torsion beams 17 is opened, and the cross section preventing member 37 that increases the strength of the torsion beam 17 is provided in the opening 17b of the open cross section. . Therefore, the opened opening 17 b can be closed with the cross-section collapse preventing member 37. Thereby, while increasing the intensity | strength of the torsion beam 17, it can prevent that the opening part 17b opens with an impact. As a result, load transmission efficiency can be improved.

  Further, by providing the opening 17b with the cross-section collapse preventing member 37 that increases the strength of the torsion beam 17, the strength is improved, so that a jack-up point or the like can be set. Therefore, the weight can be reduced by eliminating the conventional parts.

  As shown in FIG. 8A, the height of the first engaging members 41 and 42 (see FIG. 3 for 42) is set to H1, and the height of the second engaging member 43 is set to H2.

  Even when the rear impact load is input from the spare tire 47 to the front wall 19a of the spare tire pan 19 or from the center frames 35, 36 (36 for FIG. 3) to the front wall 19a of the spare tire pan 19, Since the height of the engaging member 43 is H2, the load is reliably transmitted from the torsion beam 17 to the first engaging members 41 and 42 on the front floor 28 side, and the center tunnel 45 (see FIG. 4) and A load can be transmitted to the center cross member 21 via the tunnel stiffener 46.

  As shown in FIG. 8B, when a rear impact load is input from the rear of the vehicle body 11 as indicated by an arrow d1, it is transmitted to the spare tire pan 19 and the center frames 35 and 36 (see FIG. 3 for 36). At the same time, the load is transmitted to the spare tire 47. A load is transmitted from the spare tire pan 19 to the second engaging member 43 as indicated by an arrow d2, and a load is transmitted from the center frames 35 and 36 to the second engaging member 43 as indicated by an arrow d3.

  This load is transmitted to the first engagement members 41 and 42 (see FIG. 3 for 42) via the torsion beam 17, and the center tunnel 45 (see FIG. 3) is transmitted from the first engagement members 41 and 42. 4) and the tunnel stiffener 46 is transmitted as indicated by an arrow d5, and the load is transmitted from the center tunnel 45 and the tunnel stiffener 46 to the center cross member 21 as indicated by an arrow d6.

  As shown in FIGS. 9 and 10, in the vehicle body rear structure 60 of the second embodiment, the cross-section collapse preventing members 67 and 67 are formed at the corresponding portions in the opening 17 b of the torsion beam 17 facing the first engaging members 41 and 42. (One not shown).

The cross-section collapse preventing member 67 is fitted into the torsion beam 17 from the opening 17 b and is fixed by mounting screws (or clips) 68 and 68. The cross-section collapse preventing member 67 is formed with a plurality of ribs 69 to be hollow. Further, the cross-section collapse preventing member 67 is made of resin. In other words, the cross-section collapse preventing member 67 is a resin spacer fitted in the cross-section of the torsion beam 17.
As a result, the weight of the cross-section collapse preventing member 67 can be reduced.

  In the vehicle body rear structure 10 according to the present invention, as shown in FIG. 5, the second engagement member 43 includes a front wall 19 a (center floor 29) of the spare tire pan 19 that constitutes the center portion of the floor panel 18. However, the present invention is not limited to this, and may be provided at the front ends 35a, 36a of the center frames 35, 36.

  The vehicle body rear structure according to the present invention is suitable for use in passenger cars such as sedans and wagons.

  DESCRIPTION OF SYMBOLS 10 ... Vehicle body rear structure, 13, 14 ... Left and right side sills, 15, 16 ... Left and right rear frames, 17 ... Torsion beam, 17b ... Opening, 18 ... Floor panel, 19 ... Spare tire pan, 21 ... Center cross member, 22 ... middle cross member, 35, 36 ... center frame, 37 ... cross-section collapse preventing member, 45 ... floor frame (center tunnel).

Claims (3)

Left and right side sills extending back and forth on the left and right of the floor panel;
A center cross member and a middle cross member for connecting the middle and rear end portions of these side sills in the vehicle width direction, and
Left and right rear frames extending rearward from rear ends of the left and right side sills,
A floor panel which is passed between the left and right side sills and forms the floor of the passenger compartment,
In the rear structure of the vehicle body having a spare tire pan between the left and right rear frames,
A torsion beam is disposed along the middle cross member;
The front end of the center frame extending in the front-rear direction along the spare tire pan is brought close to the rear of the torsion beam,
The rear end of the floor frame connected to the center cross member is brought close to the front of the torsion beam ,
The floor frame has a first engagement member at a rear end, and has an extension portion that extends upward at the rear end of the first engagement member and connects to the middle cross member. A vehicle body rear structure characterized by being able to engage with the entire movable range of the torsion beam .   2. The rear structure of a vehicle body according to claim 1, wherein the torsion beam has an open cross section in which at least one of the torsion beams is open, and has a cross-section collapse preventing member that increases the strength of the torsion beam at an opening of the open cross section. The vehicle body rear part structure according to claim 1 , wherein the center frame has a second engaging member that engages with the torsion beam in front of the center frame and can be engaged with the entire movable range of the torsion beam.

Images